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1
Berti, Matteo. "New mechanistic insight into replication fork reversal and restart". Doctoral thesis, Scuola Normale Superiore, 2013. http://hdl.handle.net/11384/85975.
Testo completoAbstract (sommario):
An emerging model of how stalled or damaged forks are processed is that replication
fork
s can reverse to aid repair of the damage. The first evidence that replication forks
regress in human cells came from a recent study with topoisomerase I (T
op
1) inhibitors, an
important class of anticancer drugs currently in clinical use. Their cytotoxicit
y, and thus
their efficacy, has been generally linked to their ability to cause the accumulation of DNA
nicks, which are later converted into double
-
stranded breaks (DSBs) by the collision of the
DNA replication fork with the primary lesion. The discovery
that replic
ation forks can
regress upon Top
1 inhibition provided new insight into
the molecular basis of Top
1
cytotoxicity by showing that clinically relevant
, nanomolar doses of Top
1 poisons induce
replication fork slowing and reversal in a process that c
an be uncoupled from DSB
formation
and
requires poly(ADP
-
ribose) polymerase
1
(
PARP1) activity.
However,
w
hether re
versed
forks can efficiently restart
and wh
ich
factors are
involved in this
mechanism
was
still unknown.
In this thesis
,
u
sing a combination
of biochemical and
cellular approaches, we provided the first evidence that regressed forks can restart
in vivo
and identified a key role for the human RECQ1 helicase in promoting efficient re
plication
fork restart after Top
1 inhibition
that is not shared
by other human RecQ
members
.
Our
data also provided the first insight into the molecular role of PARP1 in fork reversal by
showing that the poly(ADP
-
ribosyl)ation activity of PARP inhibits RECQ1 activity on
replication forks after Top 1 inhibition. Thus, PARP activity is not required to form, but
rather to "accumulate" reversed fork structures by maintaining/protecting them from a
counteracting activity (RECQ1), which would otherwise cause an untimely restart of
reversed forks, leading to DSB formation. The
identification of a specific and controlled
biochemical activity that drives
the
restart of reversed forks strongly supports the
physiological relevance of this DNA transaction during replication stress in human cells.
Moreover, our
studies provide new mec
hanistic insights into the roles of
RECQ1 and
PARP
1
in DNA replication and offer molecular perspectives to potentiate
chemo
therapeutic regimens based on Top
1 inhibition.
2
Schalbetter, Stephanie. "Genome instability induced by structured DNA and replication fork restart". Thesis, University of Sussex, 2012. http://sro.sussex.ac.uk/id/eprint/38853/.
Testo completoAbstract (sommario):
DNA replication is a central mechanism to all forms of life. Errors occurring during DNA replication can result in mutagenesis and genome rearrangements, which can cause various diseases. In this work I have investigated the stability of direct tandem repeats (TRs) in the context of replication and replication-associated repair mechanisms. During DNA replication the replication fork encounters many obstacles, such as DNA-protein barriers, secondary DNA structures and DNA lesions. How and if replication resumes or restarts in these circumstances in order to complete genome replication is not well understood and the fidelity of replication in response to such obstacles remains unclear. I have developed TR assays to assess replication errors in the context of replication fork restart and secondary structures. The results suggest that structured DNA (G4) can cause instability of TRs in the context of normal replication and that restarted replication can be intrinsically error-prone. Surprisingly, the mutagenic effect of G4-DNA on TR stability was not elevated in the context of replication fork restart. Therefore, deletions of TRs containing G4-DNA are not more susceptible to the compromised fidelity of a restarted replication fork. Structures such as stalled replication forks can induce checkpoint responses to maintain genome stability. The stabilisation of replication forks is central in the response to replication stress. These protective mechanisms include the regulation of enzymatic activities. Mus81-Eme1 is a structure-specific endonuclease which is regulated by the DNA replication checkpoint, but has also been shown to be required for replication fork restart in certain circumstances. In collaboration with Professor Neil McDonald I analysed a novel domain identified in Mus81-Eme1. Mutagenesis of key residues deduced from the protein structure and comparison of their genetic analysis to known phenotypes of Mus81-Eme1 suggests distinct requirements for this domain.
3
Nguyen, Michael Ong. "Investigating the molecular mechanism of replication restart in fission yeast". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:b90fff59-d5b7-43b2-b648-61c0bc977ee9.
Testo completoAbstract (sommario):
Successful replication of the genome during each cell cycle requires that every replication fork merge with its opposing fork. However, lesions in the template DNA or protein-DNA barriers often impede replication forks and threaten the timely completion of genome duplication. If a fork encounters a replication fork barrier (RFB), it can be subject to a variety of fates. In some cases the replisome is maintained in a manner such that it can resume DNA synthesis when the barrier is removed. Alternatively the stalled fork is simply held in a competent state to merge with the opposing fork when it arrives. However, fork stalling can also precipitate dissociation of the replisome (fork collapse) or even fork breakage. If this happens the recombination machinery can intervene to restore DNA integrity and restart replication, albeit with a risk of causing deleterious genetic change if ectopic homologous sequences are recombined. I have exploited a site-specific RFB in fission yeast termed RTS1 to investigate the consequences of perturbing a single replication fork. RTS1 is a polar RFB (i.e. it blocks fork progression in a unidirectional fashion), enabling replication to be completed by the opposing fork. Despite this, fork blockage at RTS1 triggers a strong recombinational response that is able to restart DNA synthesis, which at least initially is highly error prone. Here, I present my work in establishing a live cell imaging approach to visualizing the recombinational response at the RTS1 RFB, demonstrating that the majority of cells initiate recombination-dependent replication (RDR). RDR begins within a few minutes of fork blockage and is only curtailed by the arrival of the opposing fork. It depends on the Rad52 protein, which remains associated with the restarted fork and whose presence correlates with its infidelity. I also illustrate the significance of various genetic factors, including Rad51, the Rad51 mediators, Fml1 helicase, Rad54 translocase, Pfh1 sweepase, and Cds1 checkpoint kinase, in modulating Rad52 localization and block-induced recombination at the RTS1 RFB.
4
Chakraborty, Shrena. "Multifaceted role of SUMOylation in maintaining centromere biology and regulation of replication fork restart in Schizosaccharomyces pombe". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASL069.
Testo completoAbstract (sommario):
Les défauts dans le processus de réplication de l'ADN, connus sous le nom de stress de réplication, sont une source majeure d'instabilité du génome qui favorise le développement du cancer. La résolution du stress de réplication se produit dans un noyau compartimenté qui présente des capacités distinctes de réparation de l'ADN. Les fourches de réplication stressées présentent une mobilité accrue et se déplacent vers la périphérie du noyau pour s'ancrer aux complexes du pore nucléaire, une structure hautement conservée de l'enveloppe nucléaire qui agit comme un site d'amarrage pour permettre à d'autres voies de réparation de l'ADN de se mettre en place. Ces changements dans le positionnement nucléaire sont régulés par le métabolisme des petits modificateurs de type ubiquitine (SUMO), qui jouent un rôle essentiel dans la ségrégation spatiale des activités de la voie de la recombinaison homologue (RH). Nos travaux antérieurs chez la levure de fission ont établi qu'une fourche de réplication bloquée par une protéine liée à l'ADN se relocalise et s'ancre au NPC d'une manière SUMO-dépendante. Les chaînes SUMO déclenchent la relocalisation des fourches arrêtées à la périphérie du noyau pour s'ancrer au NPC. Cet ancrage nécessite les chaînes SUMO et la voie de l'ubiquitine ligase ciblée par les SUMO (STUbL) Slx8. Cependant, les chaînes Cependant, les chaînes SUMO limitent également la voie de redémarrage de la fourche. Ces conjugués SUMO peuvent être éliminés par la protéase SENP Ulp1 et le protéasome, dont les activités sont enrichies à la périphérie nucléaire. Ainsi, une relocalisation vers les NPCs permet un redémarrage de la réplication dépendant de la RH en contrecarrant la toxicité des chaînes SUMO. La formation de chaînes SUMO et la voie Slx8 étant cruciales pour la relocalisation des fourches de réplications bloquées au NPC. Mon projet s'est d'abord attaché à déterminer si Slx8 STUbL pouvait être exploitée en tant que marqueur des chaînes SUMO induites par des dommages à l’ADN. Pour ce faire, j'ai marqué Slx8 avec une étiquette GFP et j’ai suivi le marquage GFP par microscopie à fluorescence. De manière inattendue, je n'ai pas pu détecter de foyers Slx8 spécifiquement induits par le stress de réplication. Cependant, j'ai découvert que Slx8 forme un foyer nucléaire unique, enrichi à la périphérie nucléaire, qui marque à la fois les centromères groupés au niveau du centre organisateur des microtubules et la région silencieuse du mating type. La formation de ce foyer unique de Slx8 nécessite la ligase E3 SUMO Pli1, la poly-SUMOylation et l'histone méthyl transférase Clr4 qui est responsable de la méthylation de l’histone H3K9 qui marque l'hétérochromatine. Enfin, j'ai établi que Slx8 favorise le regroupement des centromères et le silencing des gènes dans les domaines de l'hétérochromatine. Dans l'ensemble, mes données mettent en évidence des relations fonctionnelles et conservées au cours de l'évolution entre STUbL et les domaines de l'hétérochromatine pour promouvoir le silencing des gènes et l'organisation nucléaire. En outre, j'ai mieux caractérisé les voies de redémarrage des fourches bloquées dans l'espace nucléaire. L'équipe a précédemment établi que les fourches arrêtées nécessitent l'activité d'échange de brins de Rad51 pour être acheminées vers le NPC en vue d'un redémarrage. Dans ce contexte, j'ai dévoilé l'existence d'une voie alternative de redémarrage qui implique la mono-SUMOylation, dans le nucléoplasme en absence de relocalisation au NPC. Ici, je révèle le nouveau rôle de Rad52 dans l'orchestration du redémarrage de la fourche dans le nucléoplasme, un rôle qui implique son activité SSA (single strand annealing). Pris ensemble, mes résultats suggèrent deux aspects. Une partie souligne comment la SUMOylation régulée par Slx8 STUbL favorise la maintenance du centromère. L'autre partie élucide le “contrôle SUMO” des voies alternatives de redémarrage de fourches résolues dans l'espace nucléaireFlaws in the DNA replication process, known as replication stress, is a major source of genome instability that fuels cancer development. Resolution of replication stress occurs within a compartmentalized nucleus that exhibits distinct DNA repair capacities. In different eukaryotic organisms, stressed replication forks (RFs) shift to the nuclear periphery for anchorage to the nuclear pore complexes (NPCs), a highly conserved structure in the nuclear envelope that act as docking sites to allow alternative DNA repair pathways to occur. These changes in nuclear positioning is regulated by the small ubiquitin-like modifier (SUMO) metabolism, which is pivotal to spatially segregate the activities of the homologous recombination (HR) pathway. Our previous work in the fission yeast Schizossacharomyces pombe, has established that a replication fork blocked by a DNA-bound protein relocates and anchors to NPC in a SUMO-dependent manner. SUMO chains trigger the relocation of single arrested forks to the nuclear periphery to anchor to the NPC. This anchorage requires the SUMO chains and the SUMO-targeted ubiquitin ligase (STUbL), Slx8 pathway. However, SUMO chains also limit the Recombination-Dependent Replication (RDR) pathway, necessary to promote fork restart. These SUMO conjugates can be cleared off by the SENP protease Ulp1 and the proteasome, whose activities are enriched at the nuclear periphery. Thus, a routing towards NPCs allows HR-dependent replication restart by counteracting the toxicity of SUMO chains. Since, both SUMO chain formation and the Slx8 STUbL pathway were crucial for NPC routing of arrested replication forks. My thesis project initially focused on unraveling if the Slx8 STUbL can be exploited as a readout of damage-induced SUMO chains. To do so, I tagged Slx8 with a GFP tag and monitored them using the fluorescence microscopy technique. Unexpectedly, I was unable to detect replication stress-induced Slx8 foci. However, I discovered that Slx8 forms a single nuclear focus, enriched at the nuclear periphery, which marks both clustered centromeres at the spindle pole body and the silent mating type region. The formation of this single Slx8 focus requires the E3 SUMO ligase Pli1, poly-SUMOylation and the histone methyl transferase Clr4 that is responsible for the heterochromatin histone mark H3-K9 methylation. Finally, it was established that Slx8 promotes centromere clustering and gene silencing at heterochromatin domains. Altogether, my data highlight evolutionarily conserved and functional relationships between STUbL and heterochromatin domains to promote gene silencing and nuclear organization. Additionally, I have better characterized pathways of fork restart within the nuclear space. The team previously established that arrested RFs require SUMO chains and the strand exchange activity of Rad51 for routing to the NPC for subsequent fork restart. In this context, I unveiled the existence of an alternate fork restart pathway that occurs by mono-SUMOylation, in the nucleoplasm when forks do not shift to the NPC, as SUMO chains are not formed. Here, I revealed that fork restart within the nucleoplasm still depends on the strand exchange activity of Rad51 largely, while the single strand annealing (SSA) activity of Rad52 plays an important role in mediating error-prone fork progression in the absence of SUMO chains. Taken together, my results suggest two different ideas about SUMOylation. One part underscores how Slx8 STUbL-regulated SUMOylation promotes centromere clustering and gene silencing at heterochromatin domains. Whereas, the other section elucidates the “SUMO control” on the spatially segregated, alternative pathways of fork restart within the nuclear space. Therefore highlighting the importance of maintaining SUMO balance for preserving genome integrity
5
Jalan, Manisha. "Investigating the recombinational response to replication fork barriers in fission yeast". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:aed1673a-f967-41a5-9643-2e432052e174.
Testo completoAbstract (sommario):
Timely completion of DNA replication in each cell cycle is crucial for maintaining genomic integrity. This is often challenged by the presence of various replication fork barriers (RFBs). On collision with a RFB, the fate of the replication fork remains uncertain. In some cases, the integrity of the fork is maintained until the barrier is removed or the fork is rescued by merging with the incoming fork. However, fork stalling can cause dissociation of all of the associated replication proteins (fork collapse). If this occurs, the cell's recombination machinery can intervene to help restart replication in a process called recombination-dependent replication (RDR). Programmed protein-DNA barriers like the Replication Terminator Sequence-1 (RTS1) have been used to demonstrate that replication fork blockage can induce recombination. However, it remains unclear how efficiently this recombination gives rise to replication restart and whether the restarted replication fork exhibits the same fidelity as an origin-derived fork. It is also unknown whether accidental replication barriers induce recombination in the same manner as programmed barriers. In this study, I introduce recombination reporters at various sites downstream of RTS1 to obtain information on both the fidelity and efficiency of replication restart. I find that unlike break induced replication (BIR), the restarted fork gives rise to hyper-recombination at least 75 kb downstream of the barrier. Surprisingly, fork convergence, rather than inducing recombination, acts to prevent or curtail genetic instability associated with RDR. I also investigate a number of genetic factors that have a role in either preventing or promoting genome instability associated with the progression of the restarted fork. To compare RTS1 with an accidental protein-DNA barrier, a novel site-specific barrier system (called MarBl) was established based on the human mariner transposase, Hsmar1, binding to its transposon end. Replication fork blockage at MarBl strongly induces recombination, more so than at RTS1. This appears to be a general feature of accidental barriers as introduction of the E. coli TusB-TerB site-specific barrier in S. pombe gives rise to a similar effect. Here, I compare and contrast accidental barriers with programmed barriers. I observe that there is very little replication restart, if any, at MarBl measured by direct repeat recombination downstream. This points to the fact that accidental barriers do not trigger fork collapse in the same way as programmed RFBs and that the increased recombination that they cause may be a consequence of the inability of replication forks to terminate correctly, owing to the bi-directional nature of the barrier. Several genetic factors are assessed for their impact on MarBl-induced recombination, which further highlights both similarities and differences with RTS1-induced recombination.
6
Richards, Jodi D. "Helicases and DNA dependent ATPases of Sulfolobus solfataricus". Thesis, University of St Andrews, 2008. http://hdl.handle.net/10023/474.
Testo completoAbstract (sommario):
DNA is susceptible to various types of damage as a result of normal cellular metabolism or from environmental sources. In order to maintain genome stability a number of different, partially overlapping DNA repair pathways have evolved to tackle specific lesions or distortions in the DNA. Nucleotide excision repair (NER) is highly conserved throughout eukarya, bacteria and archaea and predominantly targets lesions that result from exposure to UV light, for example cyclobutane pyrimidine dimers and 6-4 photoproducts. The majority of archaea possess homologous of the eukaryotic repair genes and this thesis describes the isolation and the characterization of two XPB homologues identified in the crenarchaeon Sulfolobus solfataricus, SsoXPB1 and SsoXPB2. Human XPB is one of 10 proteins that make up the TFIIH transcription complex. The activity of XPB is tightly controlled by protein interactions, in particular with p52, which stimulates the ATPase activity of XPB. Rather than a conventional helicase, human XPB is thought to act as an ATP dependent conformational switch. Consistent with human XPB, however, the S. solfataricus proteins were unable to catalyse strand separation and the identification of an archaeal protein partner, Bax1, for SsoXPB2 was one of the focuses of this project. In order to maintain genome stability, the DNA must be replicated accurately with each cell cycle. When the advancing replication fork stalls at a lesion or a DNA break, it is crucial that the fork is reset and that replication continues to completion. The helicase Hel308 is thought to clear the lagging strand template of a stalled replication fork in order for replication restart to proceed via homologous recombination (HR). Although the specific function of Hel308 is not well understood, the possibilities are described in this thesis. Strand exchange proceeds to form a D-loop, followed by branch migration to increase regions of heterology during the synapsis stage of HR. No motors for branch migration have previously been recognised in archaea, although the identification of a possible candidate was investigated during this project.
7
Tolleson, Terry. "Restart an alternative for reclaiming churches /". Theological Research Exchange Network (TREN) Access this title online, 1999. http://www.tren.com/search.cfm?p068-0167.
Testo completo
8
Wong, Hing Choi. "Schedulability analysis for the abort-and-restart model". Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/8574/.
Testo completoAbstract (sommario):
In real-time systems, a schedulable task-set guarantees that all tasks complete before their deadlines. In functional programming, atomic execution provides the correctness of the program. Priority-based functional reactive programming (P-FRP) allows the usage of functional programming in the real-time system environment. The abort-and-restart (AR) is a scheme to implement P-FRP but an appropriate scheduling approach does not exist at the moment. Hence, efficient analysis is needed for the AR model. In this thesis, the schedulability analysis for the AR model is introduced and it shows that finding the critical instant for the AR model with periodic and sporadic tasks is intractable, and a new formulation is derived. Afterwards, a new priority assignment scheme is developed that has the performance close to the exhaustive search method, which is intractable for large systems. The technique of deferred preemption is employed and a new model, deferred abort (DA), provides better schedulability and dominates the non-preemptive model. Lastly, a tighter analysis is introduced and the technique of the multi-set approach from the analysis of cache related preemption delay is employed to introduce a new approach, multi-bag. The multi-bag approach can apply to both the AR model and the DA model. In the experiments, the schedulability of the AR model is improved at each stage of the research in this thesis.
9
Ahmed, Nisar. "Implicit restart schemes for Krylov subspace model reduction methods". Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340535.
Testo completo
10
Papakos, Vasilios. "Restarted Lanczos algorithms for model reduction". Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404818.
Testo completo
11
Rokop, Megan E. 1978. "Characterization of two Bacillus subtilis proteins required for the initiation, restart, and control of DNA replication". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28673.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2004."September 2004."
Includes bibliographical references.
(cont.) This is consistent with an inability of dnaBS371P cells to adjust the frequency of initiation according to growth rate. I also found that cells over-producing DnaBS371P are filamentous, contain decreased DNA contents, and are hypersensitive to DNA-damaging agents. These abnormalities may result from a defect in replication restart at damaged or stalled replication forks. Thus, whereas dnaBS3 71P suppresses the defects of mutant cells that cannot initiate or restart replication, expressing DnaBS371P in wild-type cells causes defects in initiation and restart.
DnaB and DnaD are essential proteins that function in the initiation and control of DNA replication in Bacillus subtilis. I found that DnaB and DnaD are required to load the replicative helicase onto chromosomal origins during replication initiation. DnaB and DnaD are also involved in loading helicase during replication restart at sites of stalled replication forks. Despite the fact that DnaB and DnaD are thought to work together to load helicase, DnaB and DnaD are found in separate subcellular compartments. I showed that DnaB is found in the membrane fraction of cells, and DnaD is found in the cytoplasmic fraction. This separation could prevent helicase loading during the majority of the cell cycle. I isolated a missense mutation in dnaB, dnaBS371P, that disrupts the spatial separation of DnaB and DnaD. I isolated dnaBS371P as a suppressor of the temperature sensitivity of dnaBts cells and dnaDts cells. dnaBS3 71P also suppresses the growth defects of ipriA cells, which cannot restart replication at stalled forks. I found that a significant fraction of DnaD is found in the membrane fraction of dnaBS371P cells. In addition, I observed a direct interaction between DnaBS371P and DnaD that is not observed between the wild-type proteins. I hypothesize that the DnaB-DnaD interaction is regulated, thereby controlling when these two proteins converge at the membrane to coordinate helicase loading. dnaBS3 71P cells lack proper control of replication, suggesting that the spatial separation of DnaB and DnaD is an important mechanism of replication control in B. subtilis. I showed that dnaBS371P cells over-initiate replication when grown slowly in minimal medium, but contain decreased DNA content when grown faster, in rich medium.
by Megan E. Rokop.
Ph.D.
12
Chromáčková, Klára. "ÚLOHA EVROPSKÝCH FONDŮ PŘI ŘEŠENÍ NEZAMĚSTNANOSTI NA ČESKOLIPSKU V LETECH 2007 - 2011". Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-149809.
Testo completoAbstract (sommario):
The thesis deals with unemployment in the district of Ceska Lipa within the period 2007 -- 2011. During this time, two of main employers in the region dismissed large number of its employees. The massive layoffs during the economic crisis meant significant increase in the unemployment rate, especially when a number of vacancies was declining. Thus, labour office in Ceska Lipa decided to use resources from the European Social Fund and implement projects called "Restart for Ceskolipsko" and "Restart means a new chance" The thesis deals with the impact of these project on unemployment in the district, quantifies the costs of projects, how many participants within the projects succeeded or failed to employ. In addition, the aim of this thesis is to find out whether the projects implementation affected the occupational structure in the district, early retirement and the development of labor conditions in the region.
13
Benner, P., e H. Faßbender. "A restarted symplectic Lanczos method for the Hamiltonian eigenvalue problem". Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800797.
Testo completoAbstract (sommario):
A restarted symplectic Lanczos method for the Hamiltonian eigenvalue problem is presented. The Lanczos vectors are constructed to form a symplectic basis. Breakdowns and near-breakdowns are overcome by inexpensive implicit restarts. The method is used to compute eigenvalues, eigenvectors and invariant subspaces of large and sparse Hamiltonian matrices and low rank approximations to the solution of continuous-time algebraic Riccati equations with large and sparse coefficient matrices.
14
Cooper, Amanda. "Explicitly restarted Lanczos methods for the computation of partial solutions for large eigenvalue problems". Thesis, University of Ulster, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274034.
Testo completo
15
Fernandes, José Pedro Girão. "Business plan for RestCard: the implementation of an innovative concept in Portugal". Master's thesis, NSBE - UNL, 2014. http://hdl.handle.net/10362/11690.
Testo completo
16
Jacobs, Teri A. "Conservation Matters: Applied Geography for Habitat Assessments to Maintain and Restore Biodiversity". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1505148939598755.
Testo completo
17
Dordevic, Jovan <1996>. "Digital Restoration Proposals for the Basilica of Santa Maria Assunta in Torcello". Master's Degree Thesis, Università Ca' Foscari Venezia, 2022. http://hdl.handle.net/10579/20993.
Testo completoAbstract (sommario):
One of the recent developments in the digital domain is its application to the preservation and
presentation of cultural heritage. Although a lot has been done on describing and improving the technical
aspect of it, insufficient attention has been given to its theoretical aspect. Especially to the part that concerns
the relation between the practical philosophical and ethical postulates of contemporary conservation and
restoration practice and the sphere of digital restoration. Therefore, the aim of this paper is to present,
examine, and offer a possible understanding of the theory of digital restoration, as well as its relation to its
practical counterpart. The case study on which the whole research is applied is the basilica of Santa Maria
Assunta on the island of Torcello, located in the northern part of the Venetian lagoon.
After presenting a brief history of the church itself, the thesis is developed towards the presentation
and examination of the ‘Brandian’ postulates and their applicability in complex cases i.e. multilayered
frescoes. The next step is to present and understand how the digital approach to restoration functions; to
examine its pros and cons. This is further explained in comparison with the practical (Brandian) approach.
By doing this, my aim is to stress the good potential that digital restoration has, especially in the field of
presentation, communication, and education of the public regarding cultural heritage.
The second part of the thesis is dedicated to the application of the ideas and postulates presented in
the previous part to the specific case studies. The first one is the problem of two strata (a mosaic decoration
placed over a fresco) and solving the complex issue of recreating a historical setting such as the interior of
the apse from the 12th century. I will propose a few visual solutions for this problem that can be used for
creating digital models and for a simplified narrative for educating the visitors. The second case is that of
fresco fragments located in a place unreachable for people. Here I will examine the potentials of material
and digital copies as a deductive tool. The third case is that of the crypt, which has a multilayered fresco, a
dismantled altar, and lacks the original decoration of a sky with stars. In this case, the parts of the original
medieval altar have been reused for making several other objects. Hence, the digital restoration can help
with reassembling the altar, regardless of the actual practice with the remaining pieces. The final part is
telling the narrative of the changes that occurred to the main portal, seen both from the outside, as well as
on the mosaic covering the inner side of the western wall.
18
Taljaard, Daniel Jacobus. "The evaluation of different technologies to restore old cultivated lands / Daniel Jacobus Taljaard". Thesis, North-West University, 2008. http://hdl.handle.net/10394/2128.
Testo completo
19
Olsson, Timmy. "Methodically selecting a test framework for RESTA literature review". Thesis, Umeå universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149687.
Testo completoAbstract (sommario):
Representational state transfer (REST), is an architecture style for network related software. It was proposed by Roy Thomas Fielding as his Ph.D. dissertation in the year 2000. It intended to improve scalability and simplify the designing. In 2016, the Swedish tax agency (Skatteverket) has begun replacing old services related to their information system (BasInfo) with RESTful web services. This requires rigorous testing, planning, and evaluation to assure it works. At the same time, they adapted agile as their development process, which added additional requirements for how the software is going to be tested. The goal of this thesis is to provide research about methods and frameworks that are meant for testing REST. It includes defining what functionalities a test framework should have, and how it stands in regards to the agile practice. We will conduct a literature review, which will describe the methods and frameworks, by how they work, their purpose and an analysis of what functionalities are relied on. They are evaluated based on their drawbacks and advantages in regards to agile view on time, quality and learning curve. From our research, we discovered there was two type of methods and frameworks. It indicated that a framework should have the capabilities of a general-purpose programming language, support generation of test cases and test data. Furthermore, it also showed potential in the aspect of agile’s view on time, quality and learning curve.
20
Egwutuoha, Ifeanyi Paulinus. "A proactive fault tolerance framework for high performance computing (HPC) systems in the cloud". Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/11484.
Testo completoAbstract (sommario):
High Performance Computing (HPC) systems have been widely used by scientists and researchers in both industry and university laboratories to solve advanced computation problems. Most advanced computation problems are either data-intensive or computation-intensive. They may take hours, days or even weeks to complete execution. For example, some of the traditional HPC systems computations run on 100,000 processors for weeks. Consequently traditional HPC systems often require huge capital investments. As a result, scientists and researchers sometimes have to wait in long queues to access shared, expensive HPC systems. Cloud computing, on the other hand, offers new computing paradigms, capacity, and flexible solutions for both business and HPC applications. Some of the computation-intensive applications that are usually executed in traditional HPC systems can now be executed in the cloud. Cloud computing price model eliminates huge capital investments. However, even for cloud-based HPC systems, fault tolerance is still an issue of growing concern. The large number of virtual machines and electronic components, as well as software complexity and overall system reliability, availability and serviceability (RAS), are factors with which HPC systems in the cloud must contend. The reactive fault tolerance approach of checkpoint/restart, which is commonly used in HPC systems, does not scale well in the cloud due to resource sharing and distributed systems networks. Hence, the need for reliable fault tolerant HPC systems is even greater in a cloud environment. In this thesis we present a proactive fault tolerance approach to HPC systems in the cloud to reduce the wall-clock execution time, as well as dollar cost, in the presence of hardware failure. We have developed a generic fault tolerance algorithm for HPC systems in the cloud. We have further developed a cost model for executing computation-intensive applications on HPC systems in the cloud. Our experimental results obtained from a real cloud execution environment show that the wall-clock execution time and cost of running computation-intensive applications in the cloud can be considerably reduced compared to checkpoint and redundancy techniques used in traditional HPC systems.
21
Mazzon, Cristian <1982>. "ORMOCER®s as protective coating materials for outdoor bronze objects: evaluation after 17 years of natural exposure". Master's Degree Thesis, Università Ca' Foscari Venezia, 2013. http://hdl.handle.net/10579/3439.
Testo completo
22
Iparraguirre, Arce Jose Arnol. "Aplicación Mateplay Go para mejorar las operaciones básicas de suma y resta en niños de primer grado". Bachelor's thesis, Universidad Católica Santo Toribio de Mogrovejo, 2021. http://hdl.handle.net/20.500.12423/3523.
Testo completoAbstract (sommario):
Actualmente los estudiantes de educación básica de grados menores presentan dificultades en cuanto al desarrollo de las operaciones básicas de suma y resta, muchas veces debido a la falta de estrategias y herramientas empleadas por los docentes. Además, se atraviesa una crisis sanitaria, una pandemia denominada La COVID-19, quien afecta gravemente al ámbito educativo y son los mismos estudiantes quienes han tenido que adaptarse a la nueva modalidad de enseñanza impartida por el Ministerio de Educación. En este contexto se realizará una investigación con el objetivo de aplicar la herramienta Mateplay Go para mejorar las operaciones básicas de suma y resta en niños del tercer ciclo de primaria. Se utilizará un diseño pre experimental con un solo grupo, manipulando una sola variable, para aplicar a una muestra de 23 estudiantes, seleccionado mediante muestreo no probabilístico por conveniencia. Como resultado se espera el 90% de los estudiantes logre desarrollar sus capacidades de cálculo mental de operaciones de suma y resta. En definitiva, la presente investigación tiene un impacto educativo, al desarrollar las competencias matemáticas de niños y niñas de primer grado de primaria logrando así los objetivos establecidos en el marco legal de educación básica del Perú CNEB (Currículo Nacional de Educación básica).
23
Coskun, Mustafa Coskun. "ALGEBRAIC METHODS FOR LINK PREDICTIONIN VERY LARGE NETWORKS". Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1499436242956926.
Testo completo
24
Yorgancioglu, Kaan. "Using Anchor Nodes for Link Prediction". Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1578499802599777.
Testo completo
25
MANCINI, GIULIA. "GANGLIOSIDE GM1 AS ADJUVANT FOR ORKAMBI® THERAPY TO RESTORE PLASMA MEMBRANE STABILITY AND FUNCTION OF F508DEL-CFTR". Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/604127.
Testo completoAbstract (sommario):
Cystic fibrosis (CF) is the most common, fatal genetic disease in the Caucasian population caused by loss of function mutations in gene encoding for the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is expressed at the apical surface of epithelial cells of different organs, such as: lungs, pancreas, gut, and testes. For this reason even if in CF the pulmonary manifestations are the most severe, CF is considered a multi-system disease, which affects several bodily districts.
The new challenge for the CF therapy is based on the development of small molecules able to rescue the function of the mutated CFTR. Many pharmacological agents have been designed to increase the surface level of mutated CFTR (correctors), as well as its plasma membrane (PM) activity (potentiators).
Recently, combined therapy that includes a corrector of the CFTR folding (lumacaftor or VX-809) and a potentiator of the channel activity (ivacaftor or VX-770) called Orkambi®, was approved for CF patients homozygous for the deletion of phenylalanine at position 508 (F508del), the most common CF-causing mutation. Unfortunately, clinical studies revealed that the effects of Orkambi® on lung function were modest, due to low stability of rescued F508del-CFTR at the PM level.
Indeed, many factors contribute to PM CFTR stability, including its compartmentalization in PM macromolecular complexes composed of phospholipids, sphingolipids, with particular regards for monosialoganglioside 1 (GM1), and scaffolding proteins such as ezrin and NHERF-1.
Interestingly, it has been proved that in bronchial epithelial cells the lack of CFTR in the cell PM, such as in the case of the patients carrying the mutation F508del, is associated with a decreased content of GM1. By performing photolabelling experiments, I demonstrated for the first time that GM1 and CFTR at PM level reside in the same microdomain, suggesting a direct interaction between them. Then I investigated on the potential effect of the exogenous administration of ganglioside GM1 on the PM stabilization and function of F508del-CFTR rescued by Orkambi® treatment. In particular, I proved that in CF bronchial epithelial cells GM1 antagonizes the negative effect of VX-770, increasing F508del-CFTR maturation and its channel activity by the recruitment of the scaffolding proteins NHERF-1 and ezrin.
Taken together the results obtained during my PhD project pointed out the role of GM1 as possible adjuvant to Orkambi® therapy to restore the function of F508del-CFTR.
26
Kilby, Allaina. "Satire for sanity : an examination of media representation and audience engagement with The Daily Show's 'Rally to Restore Sanity'". Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/70029/.
Testo completoAbstract (sommario):
This thesis examines the media representation of The Daily Show’s ‘Rally to Restore Sanity’ and the way the rally participants engaged with it. This was a unique event because of the speculation and ambiguity that surrounded it which included characterisations of activism for civil discourse, advocacy for Democrats in the run up to the Congressional mid-term election, to those labelling it as a mass comedy/music event. Also, given that The Daily Show was shifting from its television platform to the field of public protest, this was an opportunity to examine whether the rally could push the boundaries of satire by instigating a more civilised tone in America’s political news discourse. The rally would also be an opportunity to better understand the type of people that engaged with this hybrid satire event and whether their attendance was an act of civic participation.
27
Li, Hua. "RNA SEQUENCE DETERMINANTS OF A COUPLED TERMINATION-REINITIATION STRATEGY FOR TRANSLATION OF DOWNSTREAM ORF IN HELMINTHOSPORIUM VICTORIAE VIRUS 190S AND OTHER VICTORIVIRUSES (FAMILY TOTIVIRIDAE)". UKnowledge, 2014. http://uknowledge.uky.edu/plantpath_etds/9.
Testo completoAbstract (sommario):
Double-stranded RNA fungal virus Helminthosporium victoriae virus 190S (genus Victorivirus, family Totiviridae) contains two large open reading frames (ORFs) that overlap in the tetranucleotide AUGA. Translation of the downstream ORF, which encodes the RNA-dependent RNA polymerase (RdRp), was previously proposed to depend on ribosomal reinitiation following termination of the upstream ORF, which encodes the capsid protein. In this study, I provided evidence to confirm that coupled termination-reinitiation (stop-restart) is indeed used. A dual-fluorescence method was established to define the RNA sequence determinants for RdRp translation. Stop-restart depends on a 32-nt stretch of RNA sequence immediately upstream of the AUGA motif, including a predicted pseudoknot structure. The presence of similar sequence motifs and predicted RNA structures in other victoriviruses suggest that they all share a related stop–restart strategy for RdRp translation. The close proximity of the secondary structure to the AUGA motif appears to be especially important for promoting translation of the downstream ORF. Normal strong preferences for AUG start codons and canonical sequence context for translation initiation of the downstream ORF appear somewhat relaxed. With dual-fluorescence system, reinitiation efficiency of the downstream ORF was determined to be ~3.9%. Pseudoknot swapping between the one in HvV190S and those predicted from other victoriviruses showed that reinitiation from the downstream ORF of HvV190S is quite tolerant to varying primary sequences of the various pseudoknots. Mutational analysis by introducing different combinations of nucleotide mutations into pseudoknot stems reproducibly confirmed the determinant role of pseudoknot on reinitiation using two different experimental systems. Together, these results provide the first example of coupled termination-reinitiation regulated by a simple pseudoknot stucture. These data expanded the understanding of coupled termination-reinitiation mechanism employed by RNA viruses and refined a new model for genus victorivirus, the largest genus in the family Totiviridae. The dual fluorescence system used in this study represented the first application of an efficient in vivo assay for recording low-frequency events in filamentous fungi.
28
Costa, Marisa Célia da Silva Resende da. "Study of 19th century wall tiles for technical replicas development". Doctoral thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12103.
Testo completoAbstract (sommario):
Doutoramento em Engenharia CivilO principal objectivo deste trabalho foi sistematizar características físico- químicas dos azulejos para conservação e restauro de fachadas azulejares da cidade de Ovar, pertencentes à fase produtiva da semi-industrialização e industrialização dos finais do século XIX inico do século XX, de forma a produzir réplicas técnicas para recolocação nos locais de fachada com lacunas de azulejo. Além de se ter criado uma base de dados sobre estes materiais, formularam-se réplicas para os corpos cerâmicos calcários e pó de pedra, sugerindo matérias-primas e grau de moagem para a sua formulação, pressão de prensagem, ciclo e temperaturas máximas de cozedura conferindo-lhes características técnicas para que estas possam ser aplicadas lado a lado com os azulejos seculares, sem que perturbem a unicidade técnica da fachada. Investigaram-se duas das patologias mais recorrentes que afectam o vidrado: destacamento por cristalização de sais e fendilhamento. A primeira afecta a perda da parte pictórica do azulejo, atirando-o para uma remoção compulsiva da fachada aquando da sua intervenção para conservação restauro. A segunda permite-nos compreender possíveis compromissos técnicos feitos no passado.
The main objective of this work was to systematize physic-chemical characteristics of tiles removed for conservation and restoration of façades in the city of Ovar, belonging to the productive stage of semi industrialisation and industrialisation in late 19th century beginning of 20th century, in order to produce technical replicas to be used in façades gaps. Besides creating a database on these materials with an inexistent extension in Portugal, it was also achieved the lab production of replicas for ceramic bodies of calcitic tiles and pó de pedra, suggesting raw materials and its particle size, pressing pressure, maximum temperatures and firing cycle, assuring technical characteristics so that they can be applied alongside the secular tiles without disturbing the technical harmony behaviour of the facade. Two of the most recurrent pathology affecting the glaze were investigated: glaze detachment promoted by salts crystallization and crazing. The first affects the loss of the tile waterproof decoration, throwing it to a compulsory removal of the facade at its intervention for restore and conservation. The second allows us to understand possible technical commitments made in the past.
29
Das, Soumyaparna [Verfasser]. "Towards new treatments for hereditary photoreceptor degeneration : Pharmacological and genetic approaches to restore Ca2+ homeostasis and Pde6a function / Soumyaparna Das". Tübingen : Universitätsbibliothek Tübingen, 2022. http://d-nb.info/1234450895/34.
Testo completo
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Costa, Pablo Pinheiro da. "O patrimônio católico entre o movimento litúrgico e o novus ordo missæ: estudo de casos em Juiz de Fora". Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/4049.
Testo completoAbstract (sommario):
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A proteção do patrimônio edificado relaciona-se à necessidade de intervenções arquitetônicas que possibilitem que as edificações atendam às novas necessidades que aparecem com o decorrer do tempo. No caso das igrejas católicas, sua proteção está condicionada às alterações significativas que liturgia sofreu no Século XX, e que podem ser classificadas em torno de quatro eventos principais: (1) o Movimento Litúrgico (década de 1910 em diante), que repensou o papel do leigo na estrutura da liturgia; (2) o Concílio Vaticano II (1962 a 1965), que reorganizou uma série de aspectos na vida da Igreja; (3) a promulgação do Missal reformado (1969); (4) a recepção do magistério conciliar e do novo rito, ocorrida ora em “continuidade”, ora em “ruptura” com o passado. Cada um desses eventos propôs questões que, simbólica ou funcionalmente, não tinham correspondência com a espacialidade das igrejas de então, ainda herdeiras do Concílio de Trento no Século XVI. Disso tudo decorreu uma série de intervenções em igrejas de interesse cultural (não apenas no Brasil), com muitas perdas para o patrimônio. Decorridos cinquenta anos do encerramento do Concílio, cabe reavaliar quais são as intervenções necessárias que aliam preservação e possibilidade de celebração do rito reformado e, dentre as igrejas que passaram por modificações deletérias, quais intervenções restaurativas devem ser propostas agora. O presente estudo visa a mostrar que esse debate, que até o momento vem ocorrendo de forma esparsa, é relevante e deveria ter continuidade, envolvendo não apenas os segmentos tradicionalmente envolvidos nas questões patrimoniais, mas também setores da própria Igreja. Ao fim, é analisado como essas questões aparecem em intervenções de duas igrejas localizadas na cidade mineira de Juiz de Fora, ambas do período eclético e de importância para a cidade: a reforma do presbitério da Igreja de Nossa Senhora da Glória e as intervenções, em curso, na Catedral Metropolitana.
The protection of built heritage is related to architectural interventions that enable buildings to address the new needs that time may bring. In the case of catholic churches, their protection is conditioned by the significant liturgical changes that underwent in the 20th Century, that may be gathered in four major events: (1) the Liturgical Movement (1910s onward), that questioned the laity’s role in the structure of liturgy; (2) The II Vatican Council (1962-1965), that reorganized several elements in the Church; (3) the promulgation of the reformed Missal; (4) the reception of the Council magisterium and the new rite, sometimes in “continuity” and sometimes in “rupture” with regard to the past. Each of these events called for issues that, symbolically or functionally, had no counterpart to the architectural space of the existing churches, as defined by the Council of Trent in the 16th Century. A significant amount of architectural interventions has taken place since then (not only in Brazil), with the loss of many important landmarks. Fifty years after the Council was closed, it is necessary to debate what architectural interventions bind cultural preservation to the possibility of celebration of the reformed rite. In the case of churches that underwent hazardous changes, it is also necessary to discuss the proper restoration for them. This study’s goal is to show that such a debate, still relatively sparse, is relevant and should take place among professionals involved in heritage protection as well as in the Church herself. The last part depicts interventions in two churches located in Juiz de Fora, in the State of Minas Gerais, both from the eclectic period and of great relevance to the city: the reform of the presbytery of the Church of Our Lady of Glory, and the current ongoing interventions in the Cathedral.
31
VONA, Veronica. "A typological approach contribution to risk analysis: a GIS system based on widespread seismic damage for cemetery type". Doctoral thesis, Università degli studi di Ferrara, 2022. http://hdl.handle.net/11392/2496477.
Testo completoAbstract (sommario):
In Italy, the Guidelines for the evaluation and reduction of seismic risk on Cultural Heritage, and the Directive 12/12/2013 “Procedures for management of activities for cultural heritage securing and safeguarding in the event of emergencies caused by natural disasters” identify the compilation of forms to provide vulnerability and damage level representation on movable and immovable assets as an initial procedure. In particular, they establish two important survey instruments: the A-DC Churches and the B-DP Stately Buildings forms.
These are the only two instruments used between 2012 and 2013 for the damage level characterization of the cultural heritage caused by the “Emilia 2012” earthquake. The widespread use of these forms has brought to light several problems that have negatively affected the successive economic assessment of the intervention. In fact, if these sheets describe the vulnerabilities of the specialized types, such as Churches or Stately Buildings well, they are simultaneously ill suited to types with different features, which, in the Emilia-Romagna case, represent about 30% of damage to cultural heritage numerically and economically. In particular, a significant sample of these types is the cemetery type with more than 100 buildings damaged, a percentage equal to 70% of the entire complex of cemeteries located within the crater area.
Accordingly, the aim of this research is to analyse the damage suffered by this type so as to improve the damage assessment procedures, both in the emergency phase and in terms of seismic risk mitigation. The main purpose is to address the cultural heritage restoration policies towards more technically and economically sustainable actions.
Therefore, based on the data collected for the cemeteries damaged in the “Emilia 2012” earthquake, the cemetery type was investigated according to its several aspects: historic and architectural, economic, level of damage, and finally vulnerability. Each of these aspects provided the framework for the definition of a new first-level tool that could be both a damage survey tool and a proactive vulnerability assessment tool. Indeed, the complete compilation of the tool provides an estimate of the damage index and the related repair cost. The partial compilation, on the contrary, allows for the identification of the parameters for the definition of a vulnerability index correlated with a vulnerability curve specifically defined for cemeteries. In the first case it is possible to use the tool in the immediate and urgent phases of the emergency to determine the material and economic impact of the earthquake on the assets; in the second case, instead, it is possible to address the policies of seismic risk mitigation through vulnerability analyses at a territorial scale.
Finally, its status of land-management tool has resulted in its development on a GIS-based digital format for its integration within the regional technical cartography and for the on-site survey.
More than a final solution to the issue of damage assessment in cemeteries, however, this study on cemetery type should be considered as a first step towards the optimization of damage assessment procedures for building types other than churches and Stately Buildings. Only after a seismic event may the new form application provide the feedback on its effective use in emergencies and lead towards its progressive refinement.In Italia, le “Linee guida per la valutazione e la riduzione del rischio sismico del patrimonio del MIBAC” e la Direttiva 12/12/2013 “Procedure per la gestione delle attività di messa in sicurezza e salvaguardia del patrimonio culturale in caso di emergenze derivanti da calamità naturali” individuano come prima procedura conoscitiva, durante le fasi di emergenza, la redazione di schede studiate per fornire una rappresentazione del livello di danno su beni mobili ed immobili. In particolare fanno riferimento a due importantissimi strumenti di rilevo: la scheda A-DC Chiese e la scheda B-DP Palazzi. Questi sono i due strumenti attraverso i quali tra 2012 e 2013 si è preso atto dello stato del patrimonio culturale costruito dopo il terremoto in Emilia-Romagna e la cui applicazione in questo caso ha portato alla luce diverse problematiche. Tra queste, quella che maggiormente ha afflitto il processo di rilievo del danno, riverberandosi sul processo di quantificazione economica, è l’incapacità dei due strumenti sopracitati di trarre una fotografia esatta del danno per l’intero complesso dei beni culturali. Infatti, se queste schede ben interpretano le vulnerabilità intrinseche degli edifici che rappresentano, mal si adattano a tipologie con caratteristiche differenti che, nel caso dell’Emilia-Romagna, rappresentano il 30% dei beni danneggiati. Uno tra i campioni più significativi di queste tipologie è quello dei cimiteri con oltre 100 edifici danneggiati, una percentuale pari al 70% dell’intero complesso dei cimiteri collocati all’interno dell’area del cratere. La presente ricerca si è concentrata dunque sull’analisi del danno occorso a questa tipologia edilizia con obiettivo di migliorarne le procedure di rilievo del danno, sia in fase di emergenza che in chiave di mitigazione del rischio sismico. Il fine è infatti quello di indirizzare le politiche di recupero del Patrimonio Culturale verso interventi sempre più sostenibili sia tecnicamente che economicamente. A partire dunque dai dati raccolti per i cimiteri danneggiati nel sisma “Emilia 2012” il tipo cimiteriale è stato indagato nelle sue diverse componenti: storico-architettoniche, economiche, di danno ed infine di vulnerabilità. Ognuno di questi aspetti ha fornito i caratteri chiave per la definizione di un nuovo strumento di primo livello che si configurasse tanto come strumento per il rilievo del danno, quanto come strumento per la caratterizzazione della vulnerabilità del tipo in chiave proattiva. La compilazione integrale dello strumento fornisce infatti una stima dell’indice di danno e del relativo costo di riparazione. La compilazione parziale, al contrario, permette di individuare i parametri per la definizione di un indice di vulnerabilità dell’edificio correlabile con una curva di vulnerabilità specificatamente definita per i cimiteri. Nel primo caso è possibile utilizzare lo strumento nelle immediate e concitate fasi dell’emergenza per determinare l’impatto fisico ed economico del sisma sui beni, nel secondo caso, invece, è possibile effettuare valutazioni a scala territoriale per indirizzare le politiche di mitigazione del rischio sismico. La natura di strumento per la gestione del territorio ha indirizzato infine il suo sviluppo su supporto digitale di tipo GIS per l’integrazione con la cartografia tecnica regionale. Il presente contributo sull’organismo cimiteriale va però inteso come un primo passo verso l’ottimizzazione delle procedure di rilievo del danno per tipologie edilizie diverse da chiese e palazzi, e non come una risposta conclusiva al tema del rilievo del danno ai cimiteri. Solo dopo un evento sismico l’applicazione diretta della nuova scheda potrà fornirci risposte sul suo effettivo utilizzo in emergenza e guidarci verso il suo progressivo affinamento.
32
VONA, Veronica. "A typological approach contribution to risk analysis: a GIS system based on widespread seismic damage for cemetery type". Doctoral thesis, Università degli studi di Ferrara, 2022. http://hdl.handle.net/11392/2496476.
Testo completoAbstract (sommario):
In Italy, the Guidelines for the evaluation and reduction of seismic risk on Cultural Heritage, and the Directive 12/12/2013 “Procedures for management of activities for cultural heritage securing and safeguarding in the event of emergencies caused by natural disasters” identify the compilation of forms to provide vulnerability and damage level representation on movable and immovable assets as an initial procedure. In particular, they establish two important survey instruments: the A-DC Churches and the B-DP Stately Buildings forms.
These are the only two instruments used between 2012 and 2013 for the damage level characterization of the cultural heritage caused by the “Emilia 2012” earthquake. The widespread use of these forms has brought to light several problems that have negatively affected the successive economic assessment of the intervention. In fact, if these sheets describe the vulnerabilities of the specialized types, such as Churches or Stately Buildings well, they are simultaneously ill suited to types with different features, which, in the Emilia-Romagna case, represent about 30% of damage to cultural heritage numerically and economically. In particular, a significant sample of these types is the cemetery type with more than 100 buildings damaged, a percentage equal to 70% of the entire complex of cemeteries located within the crater area.
Accordingly, the aim of this research is to analyse the damage suffered by this type so as to improve the damage assessment procedures, both in the emergency phase and in terms of seismic risk mitigation. The main purpose is to address the cultural heritage restoration policies towards more technically and economically sustainable actions.
Therefore, based on the data collected for the cemeteries damaged in the “Emilia 2012” earthquake, the cemetery type was investigated according to its several aspects: historic and architectural, economic, level of damage, and finally vulnerability. Each of these aspects provided the framework for the definition of a new first-level tool that could be both a damage survey tool and a proactive vulnerability assessment tool. Indeed, the complete compilation of the tool provides an estimate of the damage index and the related repair cost. The partial compilation, on the contrary, allows for the identification of the parameters for the definition of a vulnerability index correlated with a vulnerability curve specifically defined for cemeteries. In the first case it is possible to use the tool in the immediate and urgent phases of the emergency to determine the material and economic impact of the earthquake on the assets; in the second case, instead, it is possible to address the policies of seismic risk mitigation through vulnerability analyses at a territorial scale.
Finally, its status of land-management tool has resulted in its development on a GIS-based digital format for its integration within the regional technical cartography and for the on-site survey.
More than a final solution to the issue of damage assessment in cemeteries, however, this study on cemetery type should be considered as a first step towards the optimization of damage assessment procedures for building types other than churches and Stately Buildings. Only after a seismic event may the new form application provide the feedback on its effective use in emergencies and lead towards its progressive refinement.In Italia, le “Linee guida per la valutazione e la riduzione del rischio sismico del patrimonio del MIBAC” e la Direttiva 12/12/2013 “Procedure per la gestione delle attività di messa in sicurezza e salvaguardia del patrimonio culturale in caso di emergenze derivanti da calamità naturali” individuano come prima procedura conoscitiva, durante le fasi di emergenza, la redazione di schede studiate per fornire una rappresentazione del livello di danno su beni mobili ed immobili. In particolare fanno riferimento a due importantissimi strumenti di rilevo: la scheda A-DC Chiese e la scheda B-DP Palazzi. Questi sono i due strumenti attraverso i quali tra 2012 e 2013 si è preso atto dello stato del patrimonio culturale costruito dopo il terremoto in Emilia-Romagna e la cui applicazione in questo caso ha portato alla luce diverse problematiche. Tra queste, quella che maggiormente ha afflitto il processo di rilievo del danno, riverberandosi sul processo di quantificazione economica, è l’incapacità dei due strumenti sopracitati di trarre una fotografia esatta del danno per l’intero complesso dei beni culturali. Infatti, se queste schede ben interpretano le vulnerabilità intrinseche degli edifici che rappresentano, mal si adattano a tipologie con caratteristiche differenti che, nel caso dell’Emilia-Romagna, rappresentano il 30% dei beni danneggiati. Uno tra i campioni più significativi di queste tipologie è quello dei cimiteri con oltre 100 edifici danneggiati, una percentuale pari al 70% dell’intero complesso dei cimiteri collocati all’interno dell’area del cratere. La presente ricerca si è concentrata dunque sull’analisi del danno occorso a questa tipologia edilizia con obiettivo di migliorarne le procedure di rilievo del danno, sia in fase di emergenza che in chiave di mitigazione del rischio sismico. Il fine è infatti quello di indirizzare le politiche di recupero del Patrimonio Culturale verso interventi sempre più sostenibili sia tecnicamente che economicamente. A partire dunque dai dati raccolti per i cimiteri danneggiati nel sisma “Emilia 2012” il tipo cimiteriale è stato indagato nelle sue diverse componenti: storico-architettoniche, economiche, di danno ed infine di vulnerabilità. Ognuno di questi aspetti ha fornito i caratteri chiave per la definizione di un nuovo strumento di primo livello che si configurasse tanto come strumento per il rilievo del danno, quanto come strumento per la caratterizzazione della vulnerabilità del tipo in chiave proattiva. La compilazione integrale dello strumento fornisce infatti una stima dell’indice di danno e del relativo costo di riparazione. La compilazione parziale, al contrario, permette di individuare i parametri per la definizione di un indice di vulnerabilità dell’edificio correlabile con una curva di vulnerabilità specificatamente definita per i cimiteri. Nel primo caso è possibile utilizzare lo strumento nelle immediate e concitate fasi dell’emergenza per determinare l’impatto fisico ed economico del sisma sui beni, nel secondo caso, invece, è possibile effettuare valutazioni a scala territoriale per indirizzare le politiche di mitigazione del rischio sismico. La natura di strumento per la gestione del territorio ha indirizzato infine il suo sviluppo su supporto digitale di tipo GIS per l’integrazione con la cartografia tecnica regionale. Il presente contributo sull’organismo cimiteriale va però inteso come un primo passo verso l’ottimizzazione delle procedure di rilievo del danno per tipologie edilizie diverse da chiese e palazzi, e non come una risposta conclusiva al tema del rilievo del danno ai cimiteri. Solo dopo un evento sismico l’applicazione diretta della nuova scheda potrà fornirci risposte sul suo effettivo utilizzo in emergenza e guidarci verso il suo progressivo affinamento.
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Fakroun, Abubaker A. "The Development of a Knowledge-Based Wax Deposition, Three Yield Stresses Model and Failure Mechanisms for Re-starting Petroleum Field Pipelines. Building on Chang and Boger’s Yield Stresses Model, Bidmus and Mehrotra’s Wax Deposition and Lee et al.’s Adhesive-Cohesive Failure Concepts to better Underpin Restart Operation of Waxy Crude Oil Pipelines". Thesis, University of Bradford, 2017. http://hdl.handle.net/10454/16792.
Testo completoAbstract (sommario):
Twenty years ago, Chang et al. (1998) introduced the three-yield stresses concept (dynamic, static and elastic limits) to describe yielding of waxy crude oils cooled below the wax appearance temperature (WAT). At the time, the limits in rheological instruments were such that they never actually measured the elastic-limit, a key fundamental property. Using modern instruments, this research succeeds in recording for the first time the entire yielding process down to stresses of 10-7 Pa and shear rate of 10-6 min-1 as a function of temperature, cooling rate and stress loading rate using two waxy oils of different origins and wax content. A four-yield stress model is established using derivative data (dynamic fluidity and failure acceleration). In addition, calorimetry (DSC) and microscopy (CPM) helped extract WAT, the gel and pour points and link gel crystal structure and its yielding and breakage to rheological properties.
The yielding stresses measured rheologically were tested in laboratory pipelines at two diameter scales, 6.5mm and 13.5mm to compare stresses in uniform and non-uniform cooling. It is demonstrated that rheological instruments can only predict gel breaking pressure when the cooling rate is low, i.e. yielding at the pipe wall. A complementary heat transfer study was performed on a section of pipe statically cooled, both experimentally and theoretically to predict the gel front-liquid oil interface that develops in industrial pipeline where gel breaking occurs. This key information together with rheological data provide the means to predict accurately restart pressures of shut gelled pipelines that have eluded previous research.Ministry of Higher Education of the Libyan Government
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Wecker, Alan J. "AMuse: A theoretical framework and technology for extending the museum boundaries in the physical world". Doctoral thesis, Università degli studi di Trento, 2018. https://hdl.handle.net/11572/368626.
Testo completoAbstract (sommario):
The use of intelligent presentation systems within a museum is a well-established practice. This thesis deals with connecting the museum experience with novel cultural experiences in the outside world, with attention to the individual in recognizing opportunities and delivering
tailored presentations. Our goal is to help keep the user connected to the cultural experience and to help develop further knowledge and intellectual pleasure after the museum visit. The specific goal of this research is to explore the potential of technology 1) to define contextual opportunities†, 2) to identify these contextual opportunities, 3) to select relevant material, and 4) to deliver it, given the right context, in the most appropriate way for the specific user. We review the field of personalized cultural heritage experience and technology, and related research areas, needed to serve as a grounded basis for ideas developed in the framework. We examine user preferences by reviewing data from two surveys, we conducted, in order to develop additional (from those in the background) inputs (points) for the theoretical framework model. We then describe our theoretical frameworks, both finding the next place to go, and connecting back to previous experiences. We describe the System Architecture and give three concrete examples of use cases. We report on an initial evaluation of the system (and the underlying theoretical framework) by a visitor study, followed by a discussion of possible implications.
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Sanz-Marco, Vicent. "Fault tolerance for stream programs on parallel platforms". Thesis, University of Hertfordshire, 2015. http://hdl.handle.net/2299/17110.
Testo completoAbstract (sommario):
A distributed system is defined as a collection of autonomous computers connected by a network, and with the appropriate distributed software for the system to be seen by users as a single entity capable of providing computing facilities. Distributed systems with centralised control have a distinguished control node, called leader node. The main role of a leader node is to distribute and manage shared resources in a resource-efficient manner. A distributed system with centralised control can use stream processing networks for communication. In a stream processing system, applications typically act as continuous queries, ingesting data continuously, analyzing and correlating the data, and generating a stream of results. Fault tolerance is the ability of a system to process the information, even if it happens any failure or anomaly in the system. Fault tolerance has become an important requirement for distributed systems, due to the possibility of failure has currently risen to the increase in number of nodes and the runtime of applications in distributed system. Therefore, to resolve this problem, it is important to add fault tolerance mechanisms order to provide the internal capacity to preserve the execution of the tasks despite the occurrence of faults. If the leader on a centralised control system fails, it is necessary to elect a new leader. While leader election has received a lot of attention in message-passing systems, very few solutions have been proposed for shared memory systems, as we propose. In addition, rollback-recovery strategies are important fault tolerance mechanisms for distributed systems, since that it is based on storing information into a stable storage in failure-free state and when a failure affects a node, the system uses the information stored to recover the state of the node before the failure appears. In this thesis, we are focused on creating two fault tolerance mechanisms for distributed systems with centralised control that uses stream processing for communication. These two mechanism created are leader election and log-based rollback-recovery, implemented using LPEL. The leader election method proposed is based on an atomic Compare-And-Swap (CAS) instruction, which is directly available on many processors. Our leader election method works with idle nodes, meaning that only the non-busy nodes compete to become the new leader while the busy nodes can continue with their tasks and later update their leader reference. Furthermore, this leader election method has short completion time and low space complexity. The log-based rollback-recovery method proposed for distributed systems with stream processing networks is a novel approach that is free from domino effect and does not generate orphan messages accomplishing the always-no-orphans consistency condition. Additionally, this approach has lower overhead impact into the system compared to other approaches, and it is a mechanism that provides scalability, because it is insensitive to the number of nodes in the system.
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Wecker, Alan J. "AMuse: A theoretical framework and technology for extending the museum boundaries in the physical world". Doctoral thesis, University of Trento, 2018. http://eprints-phd.biblio.unitn.it/3213/1/9_TESI.pdf.
Testo completoAbstract (sommario):
The use of intelligent presentation systems within a museum is a well-established practice. This thesis deals with connecting the museum experience with novel cultural experiences in the outside world, with attention to the individual in recognizing opportunities and delivering
tailored presentations. Our goal is to help keep the user connected to the cultural experience and to help develop further knowledge and intellectual pleasure after the museum visit. The specific goal of this research is to explore the potential of technology 1) to define contextual opportunities”, 2) to identify these contextual opportunities, 3) to select relevant material, and 4) to deliver it, given the right context, in the most appropriate way for the specific user. We review the field of personalized cultural heritage experience and technology, and related research areas, needed to serve as a grounded basis for ideas developed in the framework. We examine user preferences by reviewing data from two surveys, we conducted, in order to develop additional (from those in the background) inputs (points) for the theoretical framework model. We then describe our theoretical frameworks, both finding the next place to go, and connecting back to previous experiences. We describe the System Architecture and give three concrete examples of use cases. We report on an initial evaluation of the system (and the underlying theoretical framework) by a visitor study, followed by a discussion of possible implications.
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Bettiol, Giulia. "An integrated approach for restoration and conservation of cultural heritage structures: history, materials and structural behaviour. The arsenal of Venice". Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3421621.
Testo completoAbstract (sommario):
Restoration and conservation of the cultural and architectural heritage is a very complex topic in continuous developing. The issue raises interesting questions about the methodological approach to be followed and the objective from which it must be start for the definition of a correct restoration project.
A regulatory-wide are creating and refining of a study procedures by means of the drafting of guidelines which intent is give a methodology and a sensitization at the problem at academic level, of public organs that control the conservation and the protection of the cultural heritage, and at the private technicians that work in this field. In Italy, a “normative effort” has been done by means of the production of technical documents that establish as evaluate the problem with more awareness. The aim is providing at the technicians the Guidelines about restoration of historical heritage. In the international field, from a general point of view, it is possible to refer to the ISCARSAH Recommendations, that give a preliminary approach to the topic.
Currently, in this field different approaches are used: (1) a criteria based on the conservation, which puts attention to the form and to the materials of the building but less at the structural components, (2) a technical method that is more interested at the structure but, in many cases, involves over-dimensioned interventions than the real requirements, altering the original form and history of the building.
The thesis is included in the current standards requirement and refers to the “Guidelines for evaluation and mitigation of seismic risk of cultural heritage” and the “Recommendations for the analysis, conservation and structural restoration of architectural heritage” ISCARSAH. Based on these documents, the study aims to providing an operative procedure able to balance the two approaches mentioned above. It has been identified a integrated and multi-disciplinary method for the study of cultural heritage, created in function of the currently codes and in respect of the fundamental standard of restoration and conservation. This method was made as generic as possible, without give particular information inherent specific restoration techniques, in such a way that is applicable at all the types of buildings with elevated historical-cultural valence.
The methodology was validate through its application to two paradigmatic case studies, both located within the highly historical / sociological / architecture site, the Arsenal of Venice. The case studies are: (1) the “Sala Maggiore at the Sale d’Armi Nord” (Main Room of the North weapons rooms) and (2) the Armstrong Mitchell & Co. hydraulic crane. The choice of the two examples has been dictated by the objective requirements of the Soprintendenza B.A.P. di Venezia e Laguna (local office of the ministry of fine arts responsible for the conservation of the cultural and landscape heritage of Venice and its lagoon), to intervene in these two constructions of great historical and architectural content, which differ in geometry, materials, structural behaviour and intended use.Il restauro e la conservazione di beni storici è oggi un tema molto discusso ed in fase di evoluzione sia in Italia che all’estero. Il tema pone degli interessanti interrogativi circa la metodologia di approccio da seguire e gli obiettivi dai quali si deve partire per la definizione di un corretto progetto di restauro. A livello normativo si stanno creando e affinando delle procedure di studio mediante la stesura di linee guida che hanno lo scopo di fornire una metodologia e una sensibilizzazione al problema a livello accademico, agli enti pubblici preposti alla conservazione e al restauro, e ai tecnici che lavorano in questo ambito. È infatti in atto un processo di “sforzo normativo” per colmare queste lacune mediante la produzione di documenti tecnici che si prefiggono di valutare il problema con maggior consapevolezza fornendo linee guida per il restauro di beni storici. Attualmente la materia in esame vede due differenti tipi di approccio: da una parte il restauro conservativo, in cui viene data importanza alla forma ed alla materia e meno alla componente strutturale, e dall’altra un criterio più tecnicistico, che pone più riguardo alla struttura ma che, in molti casi, comporta degli interventi più massicci che rischiano di falsare la forma e la storia originaria del bene. La tesi proposta si inserisce nel filone delle richieste normative, dei contenuti tecnici e dei documenti di riferimento quali le Linee Guida per i Beni Culturali e, a livello europeo, le Raccomandazioni ISCARSAH, ed intende fornire una procedura operativa per porsi nel giusto mezzo tra i due approcci sopra citati. Sono stati presi in considerazione vari documenti tecnici di riferimento ed è stato identificato un metodo integrato e mutidisciplinare per lo studio di beni storici, creato in funzione delle attuali normative e nel rispetto dei fondamentali criteri del restauro e della conservazione. Si è voluto rendere tale metodo il più generico possibile, senza fornire particolari informazioni inerenti specifiche tecniche di restauro, in modo tale che sia applicabile ad i vari tipi di beni storici. Per validare tale approccio, la metodologia identificata è stata applicata a due differenti casi studio, entrambi presenti all’interno del sito ad elevato valore storico/sociologico/architettonico quale l’Arsenale di Venezia, che si differenziano tra loro per materiali, destinazioni d’uso e comportamento strutturale: la Sala Maggiore delle Sale d’Armi Nord e la gru idraulica Armstrong, Mitchell & Co. La scelta dei due casi studio è stata dettata da concrete esigenze della Soprintendenza B.A.P di Venezia e Laguna di recuperare i due beni riportandoli alla loro configurazione originaria sia materica che strutturale.
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Medeiros, Leonardo Rafael. "Unraveling knowledge gaps about cyanobacterial blooms and proposing an alternative for lake restoration". PROGRAMA DE P?S-GRADUA??O EM ECOLOGIA, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/22293.
Testo completoAbstract (sommario):
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A eutrofiza??o artificial tem sido considerada um problema de grande preocupa??o nos ecossistemas aqu?ticos em todo o mundo. Desde 1960, os avan?os cient?ficos t?m sido feitos a fim de desenvolver t?cnicas que atenuem os efeitos da eutrofiza??o. V?rios procedimentos f?sicos, qu?micos e biol?gicos podem ser usados e combinados para recuperar lagos de flora??es de cianobact?rias, como a aplica??o de um floculante combinado com argila natural ou modificada. No entanto, a efic?cia dos solos de regi?es ?ridas na mitiga??o de flora??es ? desconhecida para lagos artificiais brasileiros. Neste artigo, apresentamos uma an?lise bibliom?trica da evolu??o de publica??es sobre flora??es de cianobact?rias e identificamos registros que diretamente objetivam superar a ocorr?ncia dessas flora??es. Al?m disso, avaliamos, por meio de experimentos laboratoriais, o efeito do uso combinado do floculante policloreto de alum?nio (PAC) e um solo local do entorno do lago (LS), como lastro, no controle de flora??es de cianobact?rias em um lago raso da regi?o semi?rida do Brasil. A pesquisa bibliom?trica foi conduzida com o banco de dados "Web of Science" atrav?s da fun??o de busca ?TS = ((cyanobacteri* or blue green algae or cyanoprokariote or cyanophyceae) and (mass accumulation or bloom or domina*))?, de 1969 a junho de 2016. Realizamos uma an?lise de freq??ncia de palavras-chave e quantificamos o n?mero de registros com uma abordagem de restaura??o. Al?m disso, foram realizadas tr?s s?ries de experimentos em tr?s momentos com flora??es diferentes em composi??o e biomassa no Reservat?rio Armando Ribeiro Gon?alves. Nossa pesquisa revelou que os estudos sobre as flora??es de cianobact?rias aumentaram exponencialmente e seu impacto quantitativo nas ci?ncias aqu?ticas aumentou significativamente ao longo dos anos (F = 97,52; p <0,0001). Os EUA se destacam como a na??o mais produtiva, seguida pela China e pa?ses europeus. A China aumentou impressionantemente sua contribui??o para essa ?rea, superando os EUA nos ?ltimos cinco anos. Estudos sobre Microcystis e toxinas, tais como microcistinas, s?o tend?ncias de investiga??o, devido a sua omnipresen?a e suas consequ?ncias negativas hist?ricas. Tamb?m enfatizamos a necessidade de mais estudos com o objetivo de desenvolver t?cnicas para resolver e/ou mitigar a quest?o das flora??es. Em vista disso, nossos experimentos revelaram que o uso de PAC e LS teve um efeito not?vel na biomassa de cianobact?rias da coluna de ?gua em todas as amostragens, reduzindo at? 90% a concentra??o de clorofila-a. O uso de LS sozinho foi ineficiente para remover a biomassa de algas azuis. Em duas amostragens, a combina??o de floculante e lastro apresentou a mesma efic?cia que o uso apenas de PAC. Mesmo assim, o uso de LS ? importante para garantir a sedimenta??o. Combinado com PAC, o LS foi um lastro t?o eficiente em remover cianobact?rias quanto uma argila modificada comercialmente dispon?vel (Phoslock?). Embora LS in natura tenha liberado quantidades consider?veis de f?sforo e n?o apresentou capacidade de adsor??o de P, tal argila conseguiu adsorver quantidades moderadas de f?sforo dissolvido ap?s a mat?ria org?nica ter sido removida por muflagem. Este estudo mostra que LS ? uma alternativa economicamente vi?vel e sustent?vel para ser utilizada como a??o de manejo em reservat?rios apresentando flora??es na regi?o semi?rida do Brasil.
Artificial eutrophication has been considered a problem of major concern in aquatic ecosystems around the world. Since 1960, scientific advances have been made in order to develop techniques that mitigate the effects of eutrophication. Several physical, chemical and biological procedures can be used and combined to recover lakes from cyanobacterial blooms, such as the application of a flocculant combined with natural or modified clay. However, the efficacy of local dryland soils in mitigating blooms is unknown for Brazilian manmade lakes. In this paper, we present a bibliometric analysis of the evolution of publications about cyanobacterial blooms and identify records that directly aim to overcome the occurrence of these blooms. Also, we evaluate, through laboratory experiments, the effect of the combined use of flocculent polyaluminum chloride (PAC) and a local soil from the lake catchment (LS), as ballast, in controlling cyanobacterial bloom in a shallow lake of the semiarid region of Brazil. The bibliometric research was conducted with the ?Web of Science? database through the search function ?TS = ((cyanobacteri* or blue green algae or cyanoprokariote or cyanophyceae) and (mass accumulation or bloom or domina*))?, from 1969 to June 2016. We performed a keyword frequency analysis and quantified the number of records with a restoration approach. Besides, three sets of experiments were performed in three sampling occasions with different bloom compositions and biomass in Armando Ribeiro Gon?alves Reservoir. Our study revealed that studies about cyanobacterial blooms increased exponentially and their quantitative impact on the aquatic sciences increased significantly along the years (F = 97.52; p < 0.0001). The USA stands out as the most productive nation, followed by China and European countries. China has impressively increased its contribution to this area, surpassing the USA in the last five years. Studies about Microcystis and toxins, such as microcystins, are trends in research, due to their ubiquitousness and historical negative consequences. We also emphasize the need for more studies aiming at developing techniques to solve and/or mitigate the issue of blooms. In view of this, our experiments revealed that the use of PAC and LS had a remarkable effect on cyanobacterial biomass in the water column in all samplings, reducing up to 90% top chlorophyll-a concentration. The use of LS alone was inefficient to settle blue-green-algal biomass. In two samplings, the combination of flocculant and ballast exhibited the same efficacy as the use of solely PAC. Even so, the use of LS is important to ensure sedimentation. Combined with PAC, LS was as efficient a ballast to remove cyanobacteria as a commercially available modified clay (Phoslock?). Althugh LS in natura released considerable amounts of phosphorus and did not present P adsorption capacity, it managed to adsorb some dissolved phosphorus after organic matter was removed through muffling. This study shows that LS is a cheap, feasible and environment-friendly alternative to be used as a management action in reservoirs undergoing blooms in the semiarid region of Brazil.
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Pasaguayo, Baez Liseth Victoria. "Degradation modeling and analysis for a microgripper for intracorporeal surgery". Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCD007.
Testo completoAbstract (sommario):
Ce travail de recherche porte sur la modélisation et l'analyse de la dégradation d'une micropince pour la chirurgie intracorporelle. Nous avons d'abord mené une revue de la littérature pour identifier les limites de la mise en œuvre du pronostic et de la gestion de santé dans les microsystèmes médicaux. Deuxièmement, une méthodologie basée sur la gestion des risques selon la norme ISO 14971 pour les dispositifs médicaux a été développée afin de sélectionner les composants critiques de la micro-pince. Ensuite, les données ont été collectées sur la cinématique du système de micro-pince, en considérant les variables de position angulaire, de vitesse, d'accélération et de jerk, à travers une méthodologie incluant les exigences en matière de données, les méthodes et les protocoles. Une fois les données disponibles, une analyse des données a été réalisée, ce qui a permis de comprendre le comportement de dégradation du système de micro-pince. Cette analyse a conduit à l'identification de trois étapes distinctes de dégradation, classées en trois zones : sécurité, dégradation et critique. En outre, il a été identifié que plus la plage de fermeture est grande, plus le nombre de cycles avant l'apparition de la défaillance est faible. Enfin, pour prédire la durée de vie utile du système de micro-pince, une approche basée sur le Gradient Boosting et le réseau de neurones (acronyme anglais LSTM) a été mise en œuvre. La performance de l'approche proposée a été validée par les résultats de certaines métriques, ainsi que par la mise en œuvre de la prédiction en ligne de la vie restanteThis research work deals with the degradation modeling and analysis for a microgripper for intracorporeal surgery. We first conducted a literature review to identify limitations for Prognostics and Health Management (PHM) implementation in medical microsystems. Secondly, a methodology based on risk management according to ISO 14971 for medical devices was developed to select the critical components of the microgripper. Thirdly, the data was collected on the microgripper system's kinematics, considering the angular position, velocity, acceleration, and jerk variables through a methodology that included data requirements, methods, and protocols. Once data were available, data analysis was performed, which allowed an understanding of the degradation behavior of the microgripper system, this understanding led to the identification of three distinct stages of degradation, which were categorized into three zones: safety, degradation, and critical. Moreover, it was identified the larger the closing range, the lower the number of cycles before failure occurs. Lastly, to predict the remaining useful life (RUL) of the microgripper system, a machine learning and deep learning approach was implemented. This approach consisted of fusing Gradient Boosting and Long short-term memory (LSTM) results to predict the RUL. The proposed approach performance was validated by the results of the RMSE, MAE, and R^2 metrics, as well as the online RUL implementation
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Bentria, Dounia. "Combining checkpointing and other resilience mechanisms for exascale systems". Thesis, Lyon, École normale supérieure, 2014. http://www.theses.fr/2014ENSL0971/document.
Testo completoAbstract (sommario):
Dans cette thèse, nous nous sommes intéressés aux problèmes d'ordonnancement et d'optimisation dans des contextes probabilistes. Les contributions de cette thèse se déclinent en deux parties. La première partie est dédiée à l’optimisation de différents mécanismes de tolérance aux pannes pour les machines de très large échelle qui sont sujettes à une probabilité de pannes. La seconde partie est consacrée à l’optimisation du coût d’exécution des arbres d’opérateurs booléens sur des flux de données.Dans la première partie, nous nous sommes intéressés aux problèmes de résilience pour les machines de future génération dites « exascales » (plateformes pouvant effectuer 1018 opérations par secondes).Dans le premier chapitre, nous présentons l’état de l’art des mécanismes les plus utilisés dans la tolérance aux pannes et des résultats généraux liés à la résilience.Dans le second chapitre, nous étudions un modèle d’évaluation des protocoles de sauvegarde de points de reprise (checkpoints) et de redémarrage. Le modèle proposé est suffisamment générique pour contenir les situations extrêmes: d’un côté le checkpoint coordonné, et de l’autre toute une famille de stratégies non-Coordonnées. Nous avons proposé une analyse détaillée de plusieurs scénarios, incluant certaines des plateformes de calcul existantes les plus puissantes, ainsi que des anticipations sur les futures plateformes exascales.Dans les troisième, quatrième et cinquième chapitres, nous étudions l'utilisation conjointe de différents mécanismes de tolérance aux pannes (réplication, prédiction de pannes et détection d'erreurs silencieuses) avec le mécanisme traditionnel de checkpoints et de redémarrage. Nous avons évalué plusieurs modèles au moyen de simulations. Nos résultats montrent que ces modèles sont bénéfiques pour un ensemble de modèles d'applications dans le cadre des futures plateformes exascales.Dans la seconde partie de la thèse, nous étudions le problème de la minimisation du coût de récupération des données par des applications lors du traitement d’une requête exprimée sous forme d'arbres d'opérateurs booléens appliqués à des prédicats sur des flux de données de senseurs. Le problème est de déterminer l'ordre dans lequel les prédicats doivent être évalués afin de minimiser l'espérance du coût du traitement de la requête. Dans le sixième chapitre, nous présentons l'état de l'art de la seconde partie et dans le septième chapitre, nous étudions le problème pour les requêtes exprimées sous forme normale disjonctive. Nous considérons le cas plus général où chaque flux peut apparaître dans plusieurs prédicats et nous étudions deux modèles, le modèle où chaque prédicat peut accéder à un seul flux et le modèle où chaque prédicat peut accéder à plusieurs fluxIn this thesis, we are interested in scheduling and optimization problems in probabilistic contexts. The contributions of this thesis come in two parts. The first part is dedicated to the optimization of different fault-Tolerance mechanisms for very large scale machines that are subject to a probability of failure and the second part is devoted to the optimization of the expected sensor data acquisition cost when evaluating a query expressed as a tree of disjunctive Boolean operators applied to Boolean predicates. In the first chapter, we present the related work of the first part and then we introduce some new general results that are useful for resilience on exascale systems.In the second chapter, we study a unified model for several well-Known checkpoint/restart protocols. The proposed model is generic enough to encompass both extremes of the checkpoint/restart space, from coordinated approaches to a variety of uncoordinated checkpoint strategies. We propose a detailed analysis of several scenarios, including some of the most powerful currently available HPC platforms, as well as anticipated exascale designs.In the third, fourth, and fifth chapters, we study the combination of different fault tolerant mechanisms (replication, fault prediction and detection of silent errors) with the traditional checkpoint/restart mechanism. We evaluated several models using simulations. Our results show that these models are useful for a set of models of applications in the context of future exascale systems.In the second part of the thesis, we study the problem of minimizing the expected sensor data acquisition cost when evaluating a query expressed as a tree of disjunctive Boolean operators applied to Boolean predicates. The problem is to determine the order in which predicates should be evaluated so as to shortcut part of the query evaluation and minimize the expected cost.In the sixth chapter, we present the related work of the second part and in the seventh chapter, we study the problem for queries expressed as a disjunctive normal form. We consider the more general case where each data stream can appear in multiple predicates and we consider two models, the model where each predicate can access a single stream and the model where each predicate can access multiple streams
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Simpson, Daniel Peter. "Krylov subspace methods for approximating functions of symmetric positive definite matrices with applications to applied statistics and anomalous diffusion". Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/29751/1/Simpson_Final_Thesis.pdf.
Testo completoAbstract (sommario):
Matrix function approximation is a current focus of worldwide interest and finds application in a variety of areas of applied mathematics and statistics. In this thesis we focus on the approximation of A^(-α/2)b, where A ∈ ℝ^(n×n) is a large, sparse symmetric positive definite matrix and b ∈ ℝ^n is a vector. In particular, we will focus on matrix function techniques for sampling from Gaussian Markov random fields in applied statistics and the solution of fractional-in-space partial differential equations.
Gaussian Markov random fields (GMRFs) are multivariate normal random variables characterised by a sparse precision (inverse covariance) matrix. GMRFs are popular models in computational spatial statistics as the sparse structure can be exploited, typically through the use of the sparse Cholesky decomposition, to construct fast sampling methods. It is well known, however, that for sufficiently large problems, iterative methods for solving linear systems outperform direct methods.
Fractional-in-space partial differential equations arise in models of processes undergoing anomalous diffusion. Unfortunately, as the fractional Laplacian is a non-local operator, numerical methods based on the direct discretisation of these equations typically requires the solution of dense linear systems, which is impractical for fine discretisations.
In this thesis, novel applications of Krylov subspace approximations to matrix functions for both of these problems are investigated. Matrix functions arise when sampling from a GMRF by noting that the Cholesky decomposition A = LL^T is, essentially, a `square root' of the precision matrix A. Therefore, we can replace the usual sampling method, which forms x = L^(-T)z, with x = A^(-1/2)z, where z is a vector of independent and identically distributed standard normal random variables. Similarly, the matrix transfer technique can be used to build solutions to the fractional Poisson equation of the form ϕn = A^(-α/2)b, where A is the finite difference approximation to the Laplacian. Hence both applications require the approximation of f(A)b, where f(t) = t^(-α/2) and A is sparse. In this thesis we will compare the Lanczos approximation, the shift-and-invert Lanczos approximation, the extended Krylov subspace method, rational approximations and the restarted Lanczos approximation for approximating matrix functions of this form.
A number of new and novel results are presented in this thesis. Firstly, we prove the convergence of the matrix transfer technique for the solution of the fractional Poisson equation and we give conditions by which the finite difference discretisation can be replaced by other methods for discretising the Laplacian. We then investigate a number of methods for approximating matrix functions of the form A^(-α/2)b and investigate stopping criteria for these methods. In particular, we derive a new method for restarting the Lanczos approximation to f(A)b. We then apply these techniques to the problem of sampling from a GMRF and construct a full suite of methods for sampling conditioned on linear constraints and approximating the likelihood. Finally, we consider the problem of sampling from a generalised Matern random field, which combines our techniques for solving fractional-in-space partial differential equations with our method for sampling from GMRFs.
42
Simpson, Daniel Peter. "Krylov subspace methods for approximating functions of symmetric positive definite matrices with applications to applied statistics and anomalous diffusion". Queensland University of Technology, 2008. http://eprints.qut.edu.au/29751/.
Testo completoAbstract (sommario):
Matrix function approximation is a current focus of worldwide interest and finds application in a variety of areas of applied mathematics and statistics. In this thesis we focus on the approximation of A..=2b, where A 2 Rnn is a large, sparse symmetric positive definite matrix and b 2 Rn is a vector. In particular, we will focus on matrix function techniques for sampling from Gaussian Markov random fields in applied statistics and the solution of fractional-in-space partial differential equations. Gaussian Markov random fields (GMRFs) are multivariate normal random variables characterised by a sparse precision (inverse covariance) matrix. GMRFs are popular models in computational spatial statistics as the sparse structure can be exploited, typically through the use of the sparse Cholesky decomposition, to construct fast sampling methods. It is well known, however, that for sufficiently large problems, iterative methods for solving linear systems outperform direct methods. Fractional-in-space partial differential equations arise in models of processes undergoing anomalous diffusion. Unfortunately, as the fractional Laplacian is a non-local operator, numerical methods based on the direct discretisation of these equations typically requires the solution of dense linear systems, which is impractical for fine discretisations. In this thesis, novel applications of Krylov subspace approximations to matrix functions for both of these problems are investigated. Matrix functions arise when sampling from a GMRF by noting that the Cholesky decomposition A = LLT is, essentially, a `square root' of the precision matrix A. Therefore, we can replace the usual sampling method, which forms x = L..T z, with x = A..1=2z, where z is a vector of independent and identically distributed standard normal random variables. Similarly, the matrix transfer technique can be used to build solutions to the fractional Poisson equation of the form n = A..=2b, where A is the finite difference approximation to the Laplacian. Hence both applications require the approximation of f(A)b, where f(t) = t..=2 and A is sparse. In this thesis we will compare the Lanczos approximation, the shift-and-invert Lanczos approximation, the extended Krylov subspace method, rational approximations and the restarted Lanczos approximation for approximating matrix functions of this form. A number of new and novel results are presented in this thesis. Firstly, we prove the convergence of the matrix transfer technique for the solution of the fractional Poisson equation and we give conditions by which the finite difference discretisation can be replaced by other methods for discretising the Laplacian. We then investigate a number of methods for approximating matrix functions of the form A..=2b and investigate stopping criteria for these methods. In particular, we derive a new method for restarting the Lanczos approximation to f(A)b. We then apply these techniques to the problem of sampling from a GMRF and construct a full suite of methods for sampling conditioned on linear constraints and approximating the likelihood. Finally, we consider the problem of sampling from a generalised Matern random field, which combines our techniques for solving fractional-in-space partial differential equations with our method for sampling from GMRFs.
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Chaoub, Alaaeddine. "Deep learning representations for prognostics and health management". Electronic Thesis or Diss., Université de Lorraine, 2024. http://www.theses.fr/2024LORR0057.
Testo completoAbstract (sommario):
Cette thèse contribue à l'application de l'apprentissage Profond (Deep Learning) dans la prédiction de la durée de vie résiduelle (Remaining Useful Life) des équipements industriels, en traitant plusieurs défis importants. Notre recherche est motivée par des questions clés visant à développer des architectures et méthodes d'apprentissage profond pour pronostique la RUL sous diverses conditions opérationnelles, à améliorer l'interprétabilité des modèles et à faire face au manque de données en exploitant des données externes (non) labellisées. Nous avons structuré notre travail en deux parties principales. Dans la première partie, nous explorons des architectures capables de gérer la variabilité des données résultant de différentes conditions opérationnelles, sans sélection des données d'entrée. Cela nous a mené à la proposition d'une architecture MLP-LSTM-MLP. En employant un MLP en entrée, nous avons pu normaliser les représentations, améliorant ainsi les performances de prédiction malgré plusieurs conditions opérationnelles. De plus, pour améliorer l'interprétabilité, nous avons proposé de remplacer ce premier étage de MLP par un système de mélange d'experts (GMoE), permettant une décomposition interprétable basée sur les conditions opérationnelles. La seconde partie de la thèse aborde le problème de la rareté de données, un défi largement reconnu dans le domaine du pronostic et management de la santé (PHM). En introduisant des adaptateurs, c'est-à-dire des couches spécifiques aux différentes tâches qui permettent le traitement de différentes structures d'entrée/sortie, nous avons proposé une approche d'entrainement auxiliaire qui exploite des données labellisées externes, présentant une méthode qui surpasse les techniques traditionnelles trouvées dans la littérature. De plus, pour exploiter les données externes non étiquetées pour l'apprentissage auxiliaire, nous avons proposé une approche de méta-apprentissage pour déterminer automatiquement les objectifs auxiliaires à partir de ces données en les pseudo-étiquetant d'une manière qui prend en compte la tâche principale. L'objectif de cette partie de la thèse était d'exploiter un spectre plus large de données disponibles pour améliorer la performance de la prédiction de la durée de vie résiduelle. En faisant une réflexion sur notre travail, nous reconnaissons les limites des approches que nous avons proposées et nous indiquons des orientations immédiates et à long terme pour la recherche future. Celles-ci incluent le fait de relever les défis du traitement des données séquentielles longues, d'améliorer davantage l'interprétabilité des modèles, de s'attaquer à la rareté de données avec des méthodologies de formation plus avancées, et d'explorer le potentiel de l'apprentissage fédéré et des grands modèles de langage dans les contextes industrielsThis thesis contributes to the application of Deep Learning (DL) in Remaining useful life (RUL) prediction of industrial equipment, addressing significant challenges in this field. Our research is driven by the need to develop DL architectures that mitigate performance degradation under various operating conditions, to improve model interpretability, and to address data scarcity by leveraging external (un)labeled data. We structured our work into two principal parts. In the first part, we explore architectures capable of handling data variability resulting from different operating conditions, without manual feature engineering. This led us to propose an MLP-LSTM-MLP architecture. By employing an MLP at the first stage, we were able to normalize this variability, thus improving performances under such settings. Furthermore, To enhance interpretability, we proposed to replaced the first-stage MLP stage with a Gated mixture of experts (GMoE) system, enabling interpretable decomposition based on operating conditions. The second part of the thesis addresses the issue of data scarcity, a widely recognized challenge in the Prognostics and health management (PHM) field. Through the introduction of adapters, i.e. task-specific layers that address the challenge of handling multiple input/output structures, we proposed an auxiliary training approach that leverages external labeled data, presenting a method that surpasses traditional techniques found in the literature. Moreover, to utilize external unlabeled data in auxiliary training, We proposed a meta-learning approach to automatically derive auxiliary objectives from these data by pseudo-labeling them in an end-task aware manner. The goal of this part was to leverage broader spectrum of available data to improve RUL prediction performances. In reflecting upon our work, we acknowledge the limitations of the proposed approaches and suggest both immediate and long-term directions for future research. These include tackling the challenges of processing long sequence data, further improving model interpretability, addressing data scarcity with more advanced training methodologies, and exploring the potential of federated learning and large language models in industrial settings
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Luis, Maria Fernanda Freire. "Incentivando o Patrimônio: a contribuição das leis de incentivo para a preservação do patrimônio histórico - alguns casos na cidade de São Paulo". Universidade Presbiteriana Mackenzie, 2011. http://tede.mackenzie.br/jspui/handle/tede/278.
Testo completoAbstract (sommario):
Made available in DSpace on 2016-03-15T19:21:34Z (GMT). No. of bitstreams: 1
Maria Fernanda Freire Luis.pdf: 12292494 bytes, checksum: 88b98796bf6b7cae863796fc00f0ea3c (MD5)
Previous issue date: 2011-02-17The author s professional experience was the groundwork for this research. Its aim was to systematically investigate how rehabilitation projects are being made eligible for taxes incentives and exemptions by Brazilian Federal Cultural Laws (like the Rouanet law). In order to understand and explain how this process is developed, besides identifying the formal aspects of the role played by these incentive laws, this study presents a bibliographical review of some major concepts (such as historic heritage, tax exemption, restoration); consolidates the information upon the incentive laws and the necessary steps for its activation; and builds up a wide picture checking in which cases, among all the classified buildings in São Paulo with at least two different levels of protection, these fiscal incentives have been used for the revitalization of the cultural heritage. To illustrate this process it further examines three restoration works carried out in city of São Paulo, made available by the use of with funds originated from Brazilian State tax exemption incentives, with the support of private companies. The study also analyzed the quality of these rehabilitation projects and how they have contributed to the effective preservation of Brazil s cultural heritage
Esta pesquisa parte da experiência profissional da autora e buscou analisar de maneira ampla e referenciada como são analisados e aprovados os projetos de restauração de obras arquitetônicas de interesse especial com base nas leis de incentivo à cultura, notadamente pela Lei Federal de Incentivo, conhecida como Lei Rouanet. Para entender e explicar como esse processo se desenvolve, são identificados os aspectos formais do papel das leis de incentivo, apresentada uma revisão bibliográfica sobre alguns conceitos relevantes (como patrimônio cultural, renúncia fiscal, restauração) consolidando as informações sobre as leis de incentivo e sobre os passos necessários para sua ativação. Elaborou-se um quadro abrangente verificando, para o caso de São Paulo, dentre os bens tombados em pelo menos dois níveis de proteção, em que casos vêm ocorrendo o aproveitamento de incentivos fiscais para a revitalização desse patrimônio. Para exemplificar o processo, foram estudadas três obras de recuperação de edifícios históricos realizadas com recursos provenientes da renúncia fiscal do Estado Brasileiro, aplicados por empresas privadas, na cidade de São Paulo. O estudo buscou avaliar a contribuição efetiva dessas intervenções para a preservação do patrimônio cultural do país
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Foulard, Stéphane. "Online and real-time load monitoring for remaining service life prediction of automotive transmissions : damage level estimation of transmission components based on a torque acquisition". Thesis, Ecully, Ecole centrale de Lyon, 2015. http://www.theses.fr/2015ECDL0012.
Testo completoAbstract (sommario):
Ce travail de recherche propose le développement et la validation d’une méthode de prédiction in-situ et temps réel de la durée de vie utile restante des engrenages de boîtes de vitesses automobiles de série. Cette méthode est destinée à être implantée dans des unités de commande électronique standards. En s’attachant tout particulièrement à proposer une solution simple, fiable, rentable et facilement transposable pour tout type de configuration, le système se base sur la combinaison d’une méthode d’acquisition des couples agissants sur la boîte de vitesses et d’une estimation continue des niveaux d’endommagement des engrenages. Un état de l’art et les fondamentaux théoriques d’une estimation de l’endommagement par une approche de contrainte nominale et une accumulation linéaire des endommagements partiels sont abordés dans un premier temps. La structure globale de l’algorithme de calcul de l’endommagement est ensuite étudiée et l’approche méthodologique adoptée pour sa mise au point expliquée. Cette dernière repose en grande partie sur un modèle complet de véhicule valide par des essais sur route et des mesures, où une attention toute particulière est portée à la représentation des changements de rapport et de la dynamique de la boîte de vitesses. Deux types de boite de vitesses sont alors considérées, une boite manuelle standard et une boite à double embrayage, et une spécification technique pour la configuration de l’algorithme ainsi qu’une analyse des besoins pour la méthode d’acquisition des couples sont formulées. En se basant sur ces études, un observateur d’état capable de reconstruire le couple agissant sur les disques d’embrayage ainsi que le couple en sortie de boite est développé et valide. Finalement, une synthèse de la méthode complète et de l’algorithme final est adressée, et les avantages économiques et écologiques liés à l’introduction de cette méthode pour des mesures de conception légère des boîtes de vitesses automobiles sont abordés et évaluésThis research work proposes the development and the validation of an online and real-time method to predict the remaining service life of the gearwheels of automotive transmissions, with the aim of implementing it on standard control units of series-production vehicles. By focusing on the proposition of a simple, reliable and easy-to-implement solution, the system relies on the combination of an acquisition method of the torques acting in the transmission and a continuous estimation of the damage levels of the gearwheels. Firstly, a state of the art and the theoretical basics are presented concerning a damage estimation based on a nominal stress concept and a linear damage accumulation. The global structure of the damage estimation algorithm is then analyzed and the methodological approach adopted for its development is explained. This is based in principal on a drivetrain model, validated with tests and measurements, where a particular attention is paid to the representation of the gear shifts and the transmission dynamics. Two types of transmissions are considered, namely a standard manual transmission and a dual clutch transmission mounted in series-production cars. Respectively a requirement analysis for the configuration of the algorithm as well as a requirement specification for the torque acquisition method are performed. On this basis, a state observer is developed and validated, which is able to reconstruct the clutch torque and the transmission output torque. Finally, a synthesis of the complete method and the final version of the algorithm are addressed, and the economic and ecological advantages of the introduction of the method in the context of lightweight design measures are discussed and evaluated
Kurzfassung Diese Dissertation beschreibt die Entwicklung einer Online- und Echtzeit-Methode zur Vorhersage der restlichen Lebensdauer von den Zahnradern eines Kraftfahrzeuggetriebes. Diese Methode ist fur eine Implementierung auf Standard-Steuergeraten vorgesehen. Durch die Fokussierung auf eine einfache, zuverlassige und leicht zu implementierende Losung beruht die Methode auf der Kombination aus einer Drehmomenterfassungsmethode und einer kontinuierlichen Vorhersage des Schadigungsniveaus der Zahnrader. Zuerst werden der Stand der Technik und die theoretischen Grundlagen von Schadigungsberechnungen basierend auf dem Nennspannungskonzept und einer linearen Schadensakkumulation dargestellt. Danach wird die globale Struktur des Schadigungsberechnungsalgorithmus gezeigt und die fur die Entwicklung ausgewahlte methodische Vorgehensweise erlautert. Diese bezieht sich grundsatzlich auf ein durch Testfahrten und Messungen verifiziertes Antriebsstrangmodell, welches besonders die Schaltungen und die Dynamik des Getriebes berucksichtigt. Ein Serien-Handschaltgetriebe und ein Serien-Doppelkupplungsgetriebe werden betrachtet. Fur diese zwei Getriebetypen werden eine Anforderungsanalyse zur Konfiguration des Algorithmus sowie eine Anforderungsspezifikation fur die Drehmomenterfassungsmethode durchgefuhrt. Auf Basis dieser Untersuchungen wird dann ein Zustandsbeobachter zur Rekonstruktion des Kupplungs- und Getriebeausgangsdrehmoments entwickelt und validiert. Infolgedessen werden eine Synthese der kompletten Methode und die Endversion des Algorithmus vorgestellt. Abschliesend werden die Wirtschaftlichkeit sowie die okologischen Vorteile in Bezug auf die Einfuhrung der Lebensdauermonitoringmethode im Rahmen von Leichtbaumasnahmen diskutiert und bewertet
46
GASPARINI, LUCIA. "IL PATRIMONIO CULTURALE IMMATERIALE: NUOVE PROSPETTIVE CONCETTUALI, ARTISTICHE, MUSEOLOGICHE". Doctoral thesis, Università Cattolica del Sacro Cuore, 2013. http://hdl.handle.net/10280/1801.
Testo completoAbstract (sommario):
La ricerca affronta il tema del crescente spazio che la considerazione del patrimonio culturale immateriale ha acquisito nel panorama mondiale a partire dagli ultimi decenni, in particolare dal 2003, quando l’UNESCO ha stilato la Convenzione per la salvaguardia del patrimonio culturale immateriale.
Oltre a ripercorrere le tappe storiche che nel XX secolo hanno condotto a tale risultato, esso traccia un ancora poco esplorato parallelismo - formale e teorico - tra l’evoluzione del concetto di patrimonio immateriale e lo sviluppo delle forme dell’arte contemporanea a partire dal secondo dopoguerra fino ad oggi.
Tale tematica interessa anche il museo e una lettura della sua storia più recente mette in luce le conquiste e le difficoltà conseguenti l’accoglienza di manifestazioni immateriali all’interno delle collezioni.
Tale aspetto viene avvicinato anche con gli strumenti dell’estetica fenomenologica, che contribuiscono a valutare possibili future azioni museologiche e museografiche nei confronti del patrimonio immateriale, nella direzione di un maggior rispetto della collezione e di un migliore coinvolgimento dei vari pubblici.
Il contributo si sofferma altresì ad approfondire alcuni aspetti dell’architettura contemporanea, della didattica museale e dell’utilizzo delle nuove tecnologie in ambito museale valutandone utilizzi positivi o al contrario poco adeguati per una seria e fruttuosa valorizzazione del patrimonio immateriale.This PhD dissertation deals with intangible cultural heritage and museums. An increasing interest in intangible heritage has been arising in the world in these last years, especially since 2003, when UNESCO drew up the Convention for the Safeguarding of Intangible Cultural Heritage. A detailed historical review shows the steps which brought to this attainment; a formal and theoretical parallelism between intangible heritage and contemporary art is outlined too. A study on the very recent history of museums allows to underline the difficulties museum encounters in collecting intangible heritage. It’s possible to think about new museological solutions thanks to the contribution of aesthetics: the thought of phenomenology helps in finding ways to respect the collection and to involve the publics. The dissertation also deals with the contemporary architecture of museums, with museum education and with the use of new technologies in museums: some uses are bad, others are good and useful for the communication of intangible cultural heritage.
47
GASPARINI, LUCIA. "IL PATRIMONIO CULTURALE IMMATERIALE: NUOVE PROSPETTIVE CONCETTUALI, ARTISTICHE, MUSEOLOGICHE". Doctoral thesis, Università Cattolica del Sacro Cuore, 2013. http://hdl.handle.net/10280/1801.
Testo completoAbstract (sommario):
La ricerca affronta il tema del crescente spazio che la considerazione del patrimonio culturale immateriale ha acquisito nel panorama mondiale a partire dagli ultimi decenni, in particolare dal 2003, quando l’UNESCO ha stilato la Convenzione per la salvaguardia del patrimonio culturale immateriale.
Oltre a ripercorrere le tappe storiche che nel XX secolo hanno condotto a tale risultato, esso traccia un ancora poco esplorato parallelismo - formale e teorico - tra l’evoluzione del concetto di patrimonio immateriale e lo sviluppo delle forme dell’arte contemporanea a partire dal secondo dopoguerra fino ad oggi.
Tale tematica interessa anche il museo e una lettura della sua storia più recente mette in luce le conquiste e le difficoltà conseguenti l’accoglienza di manifestazioni immateriali all’interno delle collezioni.
Tale aspetto viene avvicinato anche con gli strumenti dell’estetica fenomenologica, che contribuiscono a valutare possibili future azioni museologiche e museografiche nei confronti del patrimonio immateriale, nella direzione di un maggior rispetto della collezione e di un migliore coinvolgimento dei vari pubblici.
Il contributo si sofferma altresì ad approfondire alcuni aspetti dell’architettura contemporanea, della didattica museale e dell’utilizzo delle nuove tecnologie in ambito museale valutandone utilizzi positivi o al contrario poco adeguati per una seria e fruttuosa valorizzazione del patrimonio immateriale.This PhD dissertation deals with intangible cultural heritage and museums. An increasing interest in intangible heritage has been arising in the world in these last years, especially since 2003, when UNESCO drew up the Convention for the Safeguarding of Intangible Cultural Heritage. A detailed historical review shows the steps which brought to this attainment; a formal and theoretical parallelism between intangible heritage and contemporary art is outlined too. A study on the very recent history of museums allows to underline the difficulties museum encounters in collecting intangible heritage. It’s possible to think about new museological solutions thanks to the contribution of aesthetics: the thought of phenomenology helps in finding ways to respect the collection and to involve the publics. The dissertation also deals with the contemporary architecture of museums, with museum education and with the use of new technologies in museums: some uses are bad, others are good and useful for the communication of intangible cultural heritage.
48
Wang, Chu. "Deep learning-based prognostics for fuel cells under variable load operating conditions". Electronic Thesis or Diss., Aix-Marseille, 2022. http://www.theses.fr/2022AIXM0530.
Testo completoAbstract (sommario):
Les systèmes de piles à combustible à membrane d'échange de protons (PEMFC) conviennent à diverses applications dans le domaine des transports, mais leur coût élevé et leur manque de durabilité restent les principaux facteurs limitant leur commercialisation à grande échelle. Dans les applications de transport, la détérioration des PEMFC est aggravée par des conditions de charge variables, ce qui entraîne une diminution de leur durée de vie utile restante (RUL). La gestion des pronostics et de la santé (PHM) est un outil efficace pour prévoir les risques du système, gérer les calendriers de contrôle/maintenance du système, améliorer la sécurité et la fiabilité du système, prolonger la durée de vie du système et réduire les coûts d'exploitation/maintenance. Le pronostic est une base importante et un support clé pour le PHM, et ses tâches principales incluent l'extraction d'indicateurs de santé, la prédiction des tendances de dégradation et l'estimation de la RUL. Les caractéristiques de dégradation à long terme des PEMFC sont dissimulées dans des conditions de charge variables, ce qui augmente la difficulté d'extraction des indicateurs de santé, réduit la précision de la prédiction de la dégradation et inhibe la fiabilité de l'estimation de la durée de vie. Dans cette optique, le travail de thèse part de la modélisation du comportement de dégradation des PEMFC dans des conditions de charge variables et mène des travaux de recherche sur l'extraction d'indicateurs de santé, la prédiction des tendances de dégradation à court/long terme, l'estimation RUL et l'évaluation de la fiabilitéProton exchange membrane fuel cell (PEMFC) systems are suitable for various transportation applications thanks to their compact structure, high power density, low start/running temperature, and zero carbon emissions. High cost and lack of durability of PEMFC are still the core factors limiting their large-scale commercialization. In transportation applications, the deterioration of PEMFCs is aggravated by variable load conditions, resulting in a decrease in their Remaining Useful Life (RUL). Prognostics and health management (PHM) is an effective tool to forecast potential system risks, manage system control/maintenance schedules, improve system safety and reliability, extend system life, and reduce operation/maintenance costs. Prognostics is an important foundation and key support for PHM, and its core tasks include health indicator extraction, degradation trend prediction, and RUL estimation. The long-term degradation characteristics of PEMFC are concealed in variable load conditions, which increases the difficulty of health indicator extraction, reduces the accuracy of degradation prediction, and inhibits the reliability of life estimation. In view of this, the thesis work starts from modeling the degradation behavior of PEMFC under variable load conditions and carries out research work on health indicator extraction, short/long-term degradation trend prediction, RUL estimation and reliability evaluation
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Khamassi, Marwa. "Conception de nouveaux vaccins anti-VIH basés sur des épitopes conformationels cross clade de gp41 issus d'anticorps muqueux protecteurs de sujets exposés au VIH mais restant séronégatifs (ESN) By shaping the antigen-binding site in IgA, the CH1α domain is crucial for HIV-1 protection in highly exposed sero-negative individuals IgA targeting human immunodeficiency virus-1 envelope gp41 triggers antibody-dependent cellular cytotoxicity cross-clade and cooperates with gp41-specific IgG to increase cell Lysis". Thesis, Sorbonne Paris Cité, 2019. http://www.theses.fr/2019USPCB036.
Testo completoAbstract (sommario):
Le SIDA est une infection transmise essentiellement au niveau des muqueuses génitales. Pour empêcher la transmission du virus de l'immunodéficience humaine (VIH-1), il faudrait dresser des barrières efficaces susceptibles de bloquer l'infection dès l'entrée du VIH-1 dans les muqueuses, avant l'établissement de réservoirs muqueux. Les IgA sont les principaux effecteurs immunitaires protecteurs des muqueuses génitales et participent à la protection contre la transmission muqueuse du virus. En effet, chez des femmes hautement exposées au VIH-1 qui restent séronégatives malgré des rapports sexuels non protégés avec des partenaires infectés par le VIH-1 (ESN), les IgA muqueux spécifiques de l'enveloppe virale gp41 avec des activités antivirales cross-clade puissantes sont un corrélat de protection majeur. Mais les muqueuses génitales sont aussi protégées par des IgG dont l'origine et le rôle sont actuellement réévalués. Dans ce travail, nous avons analysé l'influence de l'isotype, A ou G, sur la spécificité épitopique, les fonctions antivirales des anticorps protecteurs de sujets ESN et évalué de nouvelles fonctions antivirales médiées par le fragment constant des IgA. Pour ces études, nous avons d'abord utilisé 2 Fab IgA protecteurs issus d'une banque d'IgA muqueux provenant de femmes ESN spécifiques de régions conservées de gp41 de l'enveloppe du VIH, caractérisés au laboratoire. Ces Fab IgA (FabA) ont d'abord été transformés en Fab IgG (FabG) correspondants par génie génétique puis comparés au niveau immunochimique et fonctionnel. Ces couples FabA/G portent les mêmes paratopes mais diffèrent par leur partie CH1 (alpha ou gamma) qui dicte l'isotype. Nous avons montré que l'isotype et notamment le domaine CH1 de l'anticorps influence : i) l'affinité des Fabs pour leurs antigènes de clades A, B et C par la résonance plasmonique de surface et ELISA : les FabA ont une affinité >50x supérieure aux FabG correspondants ; ii) les fonctions antivirales : les FabA neutralisent plus efficacement l'infection de LTCD4 et le transfert du virus de cellules de Langerhans aux LTCD4 que les FabG correspondants. Puis, en prenant comme modèle expérimental l'anticorps 2F5 sous forme IgA, nous avons caractérisé une nouvelle propriété antivirale pour les IgA médiée par leur domaine Fc et montré que cet isotype est aussi capable d'induire la lyse de cellules infectées par le VIH-1 par Antibody dependent cell cytotoxicity, ADCC. Cette ADCC est médiée par des cellules effectrices (monocytes) de façon FcR alpha-dépendante. De plus, IgA et IgG spécifiques de gp41 agissent en synergie pour augmenter l'ADCC des cellules infectées par le VIH. L'ensemble de ces résultats montre que l'isotype (le domaine CH1) a une influence sur la reconnaissance et l'affinité pour l'antigène, mais aussi sur la qualité de la réponse immunitaire secondaire (fonctions antivirales). Finalement nous avons caractérisé les épitopes conformationnels de ces FabA/FabG sur des gp41 des différentes clades, A, B et C, chacune sous conformation pré et post fusion en utilisant une stratégie de biopanning couplée à une analyse in silico. Nous avons ainsi défini les épitopes conformationnels cross-clade de ces anticorps protecteurs de sujets ESN. Ils pourront servir d'immunogènes dans une stratégie vaccinale visant à reproduire la réponse IgA protectrice des ESN. Au cours de cette étude, nous avons mis en œuvre une stratégie de Reverse Vaccinology 2.0 pour caractériser, à partir d'anticorps de sujets ESN protégés de l'infection par le VIH, des épitopes conformationnels spécifiques de gp41 qui pourraient servir d'immunogènes dans une stratégie vaccinale contre le VIH. Cette approche vaccinale muqueuse pourrait conduire à diminuer les cas de nouvelles infections sexuelles par le VIH chez les femmes (les plus touchées par l'infection au niveau mondiale) mais aussi chez les hommes, ce qui reste un énorme challenge de santé publiqueAIDS is an infection transmitted mainly in the genital mucosa. It is at this level that an effective barrier should be developed to block infection from the initial entry of HIV-1 in the genitals, before establishment of mucosal reservoirs. IgA is the main protective antibody at the genital mucosa and has been suggested to be protective in vivo against HIV-1. Hence, mucosal gp41-specific IgA with strong cross-clade antiviral activity are a major protective correlate in Highly HIV- Exposed individuals that remain SeroNegative (ESN) despite unprotected sexual intercourse with infected partners. However, genital mucosa are also protected by IgG whose origin and role are currently reevaluated. In this work, we have analyzed the influence of the antibody isotype, IgA or IgG, on the epitope specificity, antiviral functions of HIV-1 protective antibodies and evaluated new antiviral functions mediated by the constant IgA regions. For this purpose we have used a library of protective Fab IgA derived from ESN women that are specific for conserved regions of the HIV-1 envelope gp41 subunit, already characterized in the laboratory (Tudor et al., Mucosal Immunol, 2009). By genetic engineering, we have first transformed two of these Fab IgA (FabA) into their corresponding Fab IgG (FabG), having the same paratopes but differing from each other by their CH1 domain (alpha or gamma). These two FabA/FabG couples were then analyzed comparatively for their epitope specificity and functional activities. We have shown that the isotype and particularly the CH1 domain influences (i) the affinity of Fabs for their antigens (gp41 and P1 of clades A, B and C) using surface plasmon resonance and ELISA : FabA have a 50- to 100-fold higher affinity than corresponding FabG ; (ii) antiviral functions: FabA more effectively neutralize CD4+ T-cells infection and transfer of HIV-1 from Langerhans cells to CD4+ T-cells than their corresponding FabG. In a second step, taking as experimental model the neutralizing HIV-1 antibody 2F5 as IgA, we demonstrated that IgA specific for gp41 were able to lyse HIV-1 infected cells in a process mediated by their Fc alpha domain, namely antibody mediated cell cytoxicity (ADCC), a function usually attributed to IgG. Furthermore, anti-gp41 IgA and IgG work in synergy to increase HIV-1-infected cell lysis. Altogether, the results show the isotype (the CH1 domain) has an influence on the recognition and affinity for the antigen, but also on the quality of the secondary immune response (antiviral functions). Finally, we characterized epitopes specific from the two FabA/FabG couples using biopanning followed by in silico analysis. Cross clade 3-dimensional epitopes were mapped on gp41 from Clade A, B and C, each in pre- or post-fusion conformation. These analyses allowed to define cross clade 3-dimensional epitopes targeted by these protective antibodies derived from ESN subjects. These epitopes could serve as immunogen in a vaccine strategy aiming at recapitulating the protective ESN IgA response. Altogether, we have used the strategy of Reverse Vaccinology 2.0 to characterize novel immunogens based on 3D-epitopes targeted by mucosal antibodies from individuals resisting HIV infection. These results should be taken into account in the design of an effective vaccine against the active clades of HIV-1 in the world (A, B and C). Such mucosal vaccine approach is necessary to decrease the number of new HIV infections among women (the most affected) but also in men, which remains a huge public health challenge
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Tsai, Chuan-Ming, e 蔡眷民. "A Framework for Zero-Loss Internet Service Restart through Application-Kernel Cooperation". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/92255346357641380319.
Testo completoAbstract (sommario):
碩士國立交通大學
資訊科學系所
92
Internet services are more and more widely used for resolving problems or finding information recently. Thus, Internet services have to run for a long time and must serve a huge number of clients concurrently. This causes them easy to suffer from the transient fault and software aging problem, which will cause serious damage when them occurs at some critical Internet services such as commercial web sites. In order to keep Internet service permanently running, we propose a zero-loss restart framework to resolve the transient fault or aging problem of Internet services. Our framework consists of three parts, the service state abstraction, the kernel I/O channel keeping kernel support, the automatic restarting mechanism kernel support. In addition, we deploy our framework on a popular tiny web server, thttpd. The former zero-loss restart mechanism such as checkpoint and restart has the shortcoming of high runtime overhead and can not totally resolve the transient fault. Another popular zero-loss restart mechanism is the FT-TCP which also has the shortcoming of high recovery time. As result of experimental, our framework only costs lower than 6.8% runtime overhead and lower than 8.5% recovery overhead to perform the zero-loss restart.