Дисертації з теми "Assisted evolution"
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Woolley, Brian G. "Novelty-Assisted Interactive Evolution of Control Behaviors." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5579.
Повний текст джерелаID: 031001574; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Kenneth O. Stanley.; Title from PDF title page (viewed August 26, 2013).; Thesis (Ph.D.)--University of Central Florida, 2012.; Includes bibliographical references (p. 129-138).
Ph.D.
Doctorate
Electrical Engineering and Computing
Engineering and Computer Science
Computer Engineering
Marshall, Andrew D. "Template-assisted program restructuring with application to communications infrastructure evolution." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0016/NQ58151.pdf.
Повний текст джерелаMartin, Marti Sergio. "Robotically assisted evolution of gold nanoparticles and their hybridation with POMs." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/8631/.
Повний текст джерелаHuang, Changwu. "Kriging-assisted evolution strategy for optimization and application in material parameters identification." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMIR05.
Повний текст джерелаIn order to reduce the cost of solving expensive optimization problems, this thesis devoted to Kriging-Assisted Covariance Matrix Adaptation Evolution Strategy (KA-CMA-ES). Several algorithms of KA-CMA-ES were developed and a comprehensive investigation on KA-CMA-ES was performed. Then applications of the developed KA-CMA-ES algorithm were carried out in material parameter identification of an elastic-plastic damage constitutive model. The results of experimental studies demonstrated that the developed KA-CMA-ES algorithms generally are more efficient than the standard CMA-ES and that the KA-CMA-ES using ARP-EI has the best performance among all the investigated KA-CMA-ES algorithms in this work. The results of engineering applications of the algorithm ARP-EI in material parameter identification show that the presented elastic-plastic damage model is adequate to describe the plastic and ductile damage behavior and also prove that the proposed KA-CMA-ES algorithm apparently improve the efficiency of the standard CMA-ES. Therefore, the KA-CMA-ES is more powerful and efficient than CMA-ES for expensive optimization problems
Badran, Ahmed. "Advances in Phage-Assisted Continuous Evolution and Application to Overcoming Bioinsecticide Resistance." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493579.
Повний текст джерелаChemical Biology
Horsman, Geoffrey Paul. "Directed evolution and structure-assisted random mutagenesis to enhance enantioselectivity of an esterase from Pseudomonas fluorescens." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33759.
Повний текст джерелаIn a second approach to improving enantioselectivity of PFE toward MBMP, the homology model was used to select amino acid residues near the stereocenter of the docked tetrahedral intermediate of the substrate. Randomization of these residues yielded a Trp29Leu mutant with E increased to 58, as well as a Phe199Trp mutant with E decreased to 2.
Petrescue, Laura. "An investigation of defect evolution in foam core sandwich structures produced using vacuum assisted resin transfer moulding." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27904.
Повний текст джерелаMutti, Jasdeep Singh. "Targeted improvement of the wheat genome by marker-assisted selection and understanding its homoeologous gene evolution and expression balance." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Dissertations/Fall2007/j_mutti_123007.pdf.
Повний текст джерелаThompson, David Brandon. "Development of Methods for Protein Delivery and the Directed Evolution of Recombinases." Thesis, Harvard University, 2014. http://nrs.harvard.edu/urn-3:HUL.InstRepos:13097816.
Повний текст джерелаTarek, Md Tawhid Bin. "Optimal High-Speed Design and Rotor Shape Modification of Multiphase Permanent Magnet Assisted Synchronous Reluctance Machines for Stress Reduction." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1510617496931844.
Повний текст джерелаErlichman, Adèle. "Développement de nouveaux modèles éco-évolutifs pour évaluer les impacts démographiques des flux de gènes assistés dans le contexte des changements climatiques." Electronic Thesis or Diss., Université de Montpellier (2022-....), 2024. http://www.theses.fr/2024UMONG005.
Повний текст джерелаBiodiversity is facing an unprecedented extinction crisis due to anthropogenic pressures, such as climate change. There is growing concern about the slow spontaneous pace of evolutionary processes relative to the high speed of environmental changes. Assisted gene flow has been introduced as the managed translocation of individuals within the historical range of a species. Its purpose is to introduce or increase the frequency of genotypes expected to confer an advantage under new or future climatic conditions, but also to increase genetic variation in targeted pop- ulations, in the hope that it can stimulate demography through heterosis and, by increasing the genetic variation on which selection can act on, the ability to adapt to a changing environment. Risks associated with assisted gene flow can include pathogen introduction, outbreeding depres- sion, genomic swamping, and increased maladaptation. There is, therefore, a strong need for guidelines and information on the optimal strategies and uncertainty associated with these prac- tices. Using both analytical predictions and simulations, we have developed demo-evolutionary models to to help identify critical parameters and sources of uncertainty when implementing these strategies. These models can help guiding assisted gene flow strategies and inform debates on the relevance of their use and optimal implementation. We first show how important taking into account the life cycle of targeted species is, as the optimal choice of individuals to translocate in long-lived species facing a changing climate is subject to a trade-off between being well adapted at the beginning and end of life. We also propose a new method for integrating evo- lution into an integral projection model (IPM) and show how only a small range of introduced genetic diversity for adaptive traits would allow a rare and endangered monocarpic perennial plant, Centaurea corymbosa, to escape extinction in a warming climate. Lastly, we show with an analytical model that if beneficial alleles are introgressed through managed gene flow between genetically distinct populations or closely related species, small and early introductions of non local genetic material minimize swamping of the local population’ genome and maximize the probability of rescue in small declining populations
Bai, Hao. "Machine learning assisted probabilistic prediction of long-term fatigue damage and vibration reduction of wind turbine tower using active damping system." Thesis, Normandie, 2021. http://www.theses.fr/2021NORMIR01.
Повний текст джерелаThis dissertation is devoted to the development of an active damping system for vibration reduction of wind turbine tower under gusty wind and turbulent wind. The presence of vibrations often leads to either an ultimate deflection on the top of wind tower or a failure due to the material’s fatigue near the bottom of wind tower. Furthermore, given the random nature of wind conditions, it is indispensable to look at this problem from a probabilistic point of view. In this work, a probabilistic framework of fatigue analysis is developed and improved by using a residual neural network. A damping system employing an active damper, Twin Rotor Damper, is designed for NREL 5MW reference wind turbine. The design is optimized by an evolutionary algorithm with automatic parameter tuning method based on exploitation and exploration
Palmier, Mathilde. "Evolution des réseaux ostéocytaire et vasculaire lors de la maturation, du vieillissement physiologique et dans un contexte physiopathologique de réparation osseuse." Electronic Thesis or Diss., Bordeaux, 2023. http://www.theses.fr/2023BORD0500.
Повний текст джерелаPopulations live longer raising public health concerns related to aging, such as the increase in fracture number due to bone frailty and the necessity to adapt treatments. Nowadays, multiple strategies are followed to prevent or slow down the loss of bone mass, and to treat fractures. They all present limitations forcing researchers to look for new treatment targets. Osteocytes represent 95 % of the cells in bone and live decades embedded inside their mineralized matrix. They have a specific shape with dendrites extending from their body towards other osteocytes, cells at the bone surface, and towards blood vessels. For a long time, they have been considered passive because of their location. However, the development of in vitro and in vivo tools enabled to identify their central role in bone mass maintenance. This is due to the fact that osteocytes are the most mechanosensitive cells in bone, meaning that they react to variations in mechanical loading coming from exercise or disuse. They are able to send signals to osteoblasts and osteoclasts to form and resorb the matrix where it is needed. Aging causes systemic hormonal and metabolic changes affecting the osteocyte network. However, a lot remains to be explored because it is still difficult to study them in their environment. In particular, the nature of their interactions with the vascular network and the changes in energy metabolism with aging need to be investigated. Moreover, very few studies considered osteocytes as having a role in the bone healing process, or an impact on the quality of the repair. Difficult fractures do not repair spontaneously and are called critical. To repair them, bone substitutes have been under development for years. Among them, bioceramics benefit from a specific interest because they are able to release Ca2+ et PO43- in their environment. Their impact on osteocytes has not been well studied, although these cells regulate calcium and phosphate metabolism. To address these different aspects, the first task of the Ph.D. work was to optimize a laser-assisted microdissection protocol to specifically collect osteocytes in their environment. Then, this method was applied to the analysis of osteocyte gene expression during maturation, aging, and during the repair of a critical-size defect in male mice. For the first part of the project, in addition to the osteocyte gene expression analysis, the evolution of the osteocyte and blood vessel network morphologies was described during maturation and aging, with the help of fluorescent imaging techniques. The opposite changes in bone morphology observed during maturation and aging were characterized by distinct, network-specific changes. The second part of the project was elaborated within a lab in the USA, the goal was to establish different techniques to analyze osteocyte energy metabolism using long-chain fatty acids as a fuel source. This led to the optimization and use of in vitro bioenergetics assays and ex vivo imaging. In the last part of the project, the osteocyte gene expression during the early phases of bone repair was analyzed. Among the genes tested, a contribution of osteocytes was identified through the genes Il6 and Dmp1, as well as an impact of the presence of the bioceramics. The different tools and techniques optimized, and the results produced during this PhD project will enable the initiation of new research studies to better understand osteocyte function in contexts still underexplored
Hamdani, Hamid. "Métamodèles pour l’étude fiabiliste des systèmes mécatroniques Métamodélisation pour une conception robuste des systèmes mécatroniques Reliability analysis of tape based chip-scale packages based metamodel Optimization of solder joints in embedded mechatronic systemsvia Kriging-assisted CMA-ES algorithm Metamodel assisted evolution strategies for global optimization of solder joints reliability in embedded mechatronic devices." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMIR12.
Повний текст джерелаMechatronic system failures are often caused by fatigue failure of the solder joints of its electronic devices. With the increasing miniaturization of electronic devices, the stress on solder joints, which provide the connection between the component outputs and the PCB, has become a major challenge. Indeed, solder joints can accept high deformation rates, but an accumulation of repeated stresses causes their premature ageing which can lead to the rupture of solder joints (thermomechanical fatigue phenomenon). Thus, the studies based on finite element simulation methods are performed to numerically investigate the lifetime of PCB-mounted devices (secondlevel reliability). The high computational costs required to solve such problems may make the optimization and reliability assessment procedure impracticable due to the high computation time of multi-physics finite element simulation. This thesis proposes on the one side, an adaptation of the CMA-ES method Assisted by the kriging metamodel for the global optimization of a given problem. The implementation of this proposed algorithm was performed in the global optimization of the solder joints in a PQFP package. The results of the numerical studies show that the proposed KA-CMA-ES algorithm is more efficient and more efficient than the standard CMA-ES algorithm. On the other side, a general methodology for reliability analysis in fatigue is proposed in this manuscript. It is based on the uncertainty modeling (loading, material properties, geometry) and aims to quantify the reliability level of the system studied for a fatigue failure scenario. A method based on metamodelling techniques is precisely proposed to address the complexity of mechatronic systems in solving the reliability problem. The metamodel is used to emulate the mechanical model behaviour while satisfying both the its efficiency and accuracy. The implementation of the proposed methodology is applied for the reliability analysis of a T-CSP package
GUEROULT, ISABELLE. "Evolution comparee des prematures d'age gestationnel inferieur ou egal a 34 semaines d'amenorrhee nes a la maternite de la belle de mai en 1985 et 1990." Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20184.
Повний текст джерелаPavelski, Lucas Marcondes. "Otimização evolutiva multiobjetivo baseada em decomposição e assistida por máquinas de aprendizado extremo." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1254.
Повний текст джерелаMany real optimization problems have more than one objective function. When the objectives are in conflict, there is a need for specialized strategies, as is the case of the Multi-objective Optimization Evolutionary Algorithms (MOEAs). However, if the functions evaluation is expensive (high computational or economical costs) many proposed MOEAs are impractical. An alternative might be the use of a machine learning model to approximate the fitness function (surrogates) in the optimization algorithm. This work proposes and investigates a framework called ELMOEA/D that aggregates state-of-the-art MOEAs based on decomposition of objectives (MOEA/D) and extreme learning machines as surrogate models. The proposed framework is tested with different MOEA/D variants and show good results in benchmark problems, compared to a literature algorithm that also encompasses MOEA/D but uses surrogate models based on radial basis function networks. The ELMOEA/D framework is also applied to the protein structure prediction problem (PSPP). Despite the fact that the results achieved by the proposed approach were not as encouraging as the ones achieved in the benchmarks (when the algorithms with and without surrogates are compared), many aspects of both algorithm and problem are explored. Finally, the ELMOEA/D framework is applied to an alternative formulation of the PSPP and the results lead to various directions for future works.
Verdú, Surroca Noemí. "Entorns d'ensenyament/aprenentatge virtual en la docència universitària: l'aprenentatge col·laboratiu mediat per ordinador." Doctoral thesis, Universitat de Lleida, 2009. http://hdl.handle.net/10803/8312.
Повний текст джерелаen entorns d'ensenyament i aprenentatge virtuals i en l'àmbit de la docència universitària. Es descriu
i s'analitza l'ús que fa el professorat d'entorns virtuals d'ensenyament/aprenentatge (E/A) de
caràcter general. Així mateix, s'exploren les possibilitats de noves formes d'ensenyar i aprendre a
través de l'ús d'entorns d'E/A dissenyats específicament per afavorir l'aprenentatge col·laboratiu
mediat per l'ordinador (CSCL).
El punt de partença del treball consisteix, d'una banda, en un anàlisi d'un recull ampli
d'investigacions realitzades sobre el tema que es presenta sistematitzat en una taula. D'altra banda
s'explora l'ús que es fa dels entorns virtuals i/o de suport virtual (WebCT i Sakai) a la universitat de
Lleida (UdL).
La part central del treball consisteix en investigar si les característiques del software utilitzat poden
ser decisives per a la millora de l'aprenentatge. Seguint un disseny quasi-experimental es
seleccionen fòrums de debat de diverses assignatures, pertanyents a entorns virtuals generals (Sakai
i WebCT) i es desenvolupen assignatures on s'empren plataformes específiques dissenyades per
afavorir el CSCL (Knowledge Forum, Synergeia, Fle3). Es comparen les aportacions fetes entre
entorns generals i específics, i entre entorns específics que requereixen catalogar les aportacions
(scaffolds de Fle3 i Synergeia) i els que no ho requereixen.
A més a més, s'analitzen les aportacions que fan els subjectes, segons diferents paràmetres
quantitatius. S'observa que els estudiants i les estudiantes universitaris fan un ús de les bastides
limitat i imprecís. Així mateix, es fa un anàlisi qualitatiu de les aportacions d'acord a un sistema de
categories fonamentat en els processos socials d'aprenentatge col·laboratiu (Stahl, 2000) i els
scaffolds de Knowledge Forum, seguint un procés de fiabilitat en la categorització.
Els resultats mostren que les diferències entre entorns generals i específics són molt poques.
S'ha constatat que en els 60 fòrums analitzats, independentment de l'entorn, la participació i la
motivació disminueixen si els missatges no són valorats pel tutor. Les aportacions són bàsicament
d'opinió i d'explicitació sobre el tema. S'observen pocs missatges on els estudiants entrin en debat
amb idees aportades anteriorment pels altres participants en el fòrum.
Finalment, es proposa estimular la participació, oferir pautes de construcció del discurs, i l'ús guiat
de les bastides, com a recursos per optimitzar l'aprenentatge virtual (o en suport virtual) per a que
sigui més col·laboratiu.
La presente investigación está centrada en el estudio del aprendizaje colaborativo mediado por
ordenador en entornos de enseñanza y aprendizaje virtuales en el ámbito de la docencia
universitaria. Se describe y analiza el uso que hace el profesorado de entornos virtuales de
enseñanza y aprendizaje (E/A) de carácter general. También se exploran las posibilidades de nuevas
formas de enseñar y aprender a través del uso de entornos (E/A) diseñados específicamente para
favorecer el aprendizaje colaborativo mediado por ordenador (CSCL).
El punto de partida del trabajo consiste, por un lado, en un análisis de una amplia selección de
investigaciones realizadas sobre el tema que se presenta sistematizado en una tabla. Por otro lado,
se explora el uso que se hace de los entornos virtuales y/o con apoyo virtual (WebCT y Sakai) en la
universidad de Lleida (UdL).
La parte central del trabajo consiste en investigar si las características del software utilizado pueden
ser decisivas para la mejora del aprendizaje. Siguiendo un diseño cuasi experimental se seleccionan
foros de diferentes asignaturas de entornos virtuales generales (Sakai y WebCT) y de entornos
específicos diseñados para favorecer el CSCL (Knowledge Forum, Synergeia, Fle3). Se comparan
las aportaciones hechas entre entornos generales y específicos, y entre entornos específicos que
requieren catalogar las aportaciones (scaffolds de Fle3 y Synergeia) y los que no lo requieren.
Además, se analizan las aportaciones que hacen los sujetos, según diferentes parámetros
cuantitativos. Se observa que los estudiantes universitarios hacen un uso de los andamiajes limitado
e impreciso. También, se hace un análisis cualitativo de las aportaciones de acuerdo a un sistema de
categorías fundamentado en los procesos sociales de aprendizaje colaborativo (Stahl, 2000) y los
scaffolds de Knowledge Forum, siguiendo un proceso de fiabilidad en la categorización.
Los resultados muestran que las diferencias entre entornos generales y específicos son muy pocas.
Se ha constatado que en los 60 foros analizados, independientemente del entorno, la participación y
la motivación disminuyen si los mensajes no son valorados por el tutor. Las aportaciones son
básicamente de opinión y explicitación sobre el tema. Se observan pocos mensajes donde los
estudiantes entren en debate con ideas aportadas anteriormente por otros participantes en el foro.
Finalmente, se propone estimular la participación, ofrecer pautas de construcción del discurso, y el
uso guiado de los andamiajes (scaffolds), como recursos para optimizar el aprendizaje virtual para
que sea más colaborativo
This research is based on computer supported collaborative learning (CSCL), which takes place in
the university teaching environment. This study describes and analyses the usage of teaching
-learning virtual environments by professors. Moreover, the advantages of new ways of teaching
and learning in CSCL environments are explored.
The starting point of this work, on the one hand, consists of the analysis of a broad collection of
researches on this topic, which is shown in a specific classification table. On the other hand, the
usage of the virtual environments and/ or virtual support (WebCT and Sakai) in the university of
Lleida (UdL) is investigated.
The core subject of the project deals with the need of sorting out whether the software used can
strongly influence the improvement on learning or not. Then, forums from different subjects are
selected, following a quasi-experimental methodology. These forums can be divided into two
groups: those which were found in general virtual environments (Sakai and WebCT) and those in
specific virtual environments (Knowledge Forum, Synergeia, Fle3). The latter were designed in
order to enhance CSCL. Later on messages from one group are compared to messages of the other
group. Besides, messages which belong to virtual specific environments (scaffolds from Fle3 and
Synergeia) and which require being catalogued are also compared to messages from a specific
environment (Knowledge Forum) which doesn't require this.
Furthermore, messages are analysed from different quantitative parameters. It is observed that
university students use scaffolds in an uncertain and limited way. Likewise, messages are analysed
qualitatively following a category system based on social processes of collaborative learning (Stahl,
2000) and the scaffolds from Knowledge Forum. In addition, this analysis has undergone a process
of reliability in the categorising stage.
Results show that there are few differences between general and specific environments. Since
firstly, it has been proved that in all of the 60 analysed forums, whatever the environment was,
participation and motivation decrease if messages aren't assessed by a tutor. Secondly, we have
come to the conclusion that students either express their own opinions, or their actual knowledge on
the topic with or without mentioning the sources of the information they are giving. Nevertheless,
there are few messages in which students comment on their classmates' ideas.
In conclusion, there are different ways to optimize virtual learning so that it becomes more
collaborative, which are the following: the participation, the scripts and the scaffolds.
Mungara, Ratheesh Kumar. "System-level performance of interference-aware spatial frequency reuse." Doctoral thesis, Universitat Pompeu Fabra, 2016. http://hdl.handle.net/10803/400869.
Повний текст джерелаLa reutilització de la freqüència espacial és l’aproximació més acceptada per tal de millorar la capacitat dels sistemes wireless mitjançant l'increment de l'eficiència espectral (bits per segon per unitat d'ample de banda). S'espera que la futura cinquena generació de sistemes wireless incorpori diverses formes de reutilització de freqüència. Això inclou la comunicació multi-input multi-output (MIMO) que permet la reutilització a través d'antenes, densificació dispositiu-a-dispositiu (D2D) que permet reutilitzar l'espectre a través d’enllaços de comunicació directa, així com un full-dúplex emprant el mateix espectre per a la comunicació en la transmissió i recepció de direccions. Aquest treball pretén determinar els límits de rendiment dels sistemes wireless emergents, basats en una densa reutilització de la freqüència espacial i en la supressió d'interferències, així com espigolar coneixement clau per al disseny de sistemes d'aquest tipus. La geometria estocàstica és l'eina que s'aplicarà a l'anàlisi que es durà a terme, modelitzant les localitzacions dins la xarxa com a punts d'un procés de Poisson. La introducció d'un ajust Gaussià a la interferència, conjuntament amb la consideració de nivells variables d'expectació espacial, han permès definir un nou marc matemàtic que fa possible unes expressions més compactes i uns resultats més significatius en comparació amb els anàlisis existents. Dins d'aquest marc, en primer lloc es prenen en consideració la multiplexació MIMO i l'aliniament d'interferència (IA, en les seves sigles en anglès). El primer esquema empra totes les dimensions espacials disponibles per a la senyalització i el segon minimitza la interferència a costa de conèixer els estats de esvaïment instantani dels transmissors i receptors, i d'una reducció en les dimensions de senyalització espacial. Malgrat l'intens treball en l'IA i la multiplexació espacial, s'ha prestat escassa atenció a tractar de comprendre el seu balanç d’enginyeria en el context d'xarxes cel.lulars de rellevància pràctica, com els de propagació de pèrdues, o les dinàmiques de esvaïment degudes a la mobilitat de l'usuari i al coneixement imperfecte dels estats de esvaïment. En aquest treball s'ha estudiat en profunditat aquest problema a través d'anàlisis tant a nivell dels enllaços com del sistema. Fins i tot en condicions de coneixement perfecte del esvaïment, l'IA resulta beneficiós sobre la multiplexació només en situacions de xarxa molt específiques i relativament infreqüents, mentre que perd tots els seus avantatges a velocitats vehiculars quan el coneixement del esvaïment és imperfecte. En segon lloc, el treball es centra en el ITLinQ i el FlashLinQ, els dos principals esquemes de canalització proposats fins al moment per controlar la interferència en xarxes D2D. S'ofereix una caracterització analítica de l'esquema ITLinQ, obrint així la porta a l'optimització dels seus paràmetres controlables. Es mostra que tots dos esquemes de canalització aconsegueixen millors resultats que l'esquema no canalitzat, amb un lleuger avantatge per al ITLinQ. Considerant la geometria de xarxa més desfavorable, el ITLinQ produeix millores múltiples en l'eficiència espectral en comparació amb la xarxa no canalitzada. Finalment, el treball introdueix els transreceptors full-dúplex en xarxes cel.lulars i caracteritza l'impacte de la interferència incrementada en el seu funcionament. A través d'anàlisis i de simulacions complementàries en una xarxa de test de Vodafone LTE, s'estableix que la interferència d'usuari a usuari té un impacte poc significatiu mentre que la interferència de base a base faria inviable l'operació full-dúplex en xarxes microcell.lulars sense gestió de les interferències. En resum, aquest tesis doctoral aporta evidència de que el multiplexat MIMO i la densificació basada en D2D juguen un paper vital en la millora de la capacitat dels sistemes wireless mentre que el IA i el full-dúplex resulten inefectius.
Shi, Liang. "Adaptive surrogate-assisted evolution." 2008. http://purl.galileo.usg.edu/uga%5Fetd/shi%5Fliang%5F200812%5Fphd.
Повний текст джерелаDirected by Khaled Rasheed. Includes an article published in The proceedings of the Genetic and Evolutionary Computation Conference. Includes bibliographical references (leaves 100-108).
Chao, Yi, and 趙貽. "A system for Phage Assisted Autonomous Continuous Directed Evolution." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/s593mh.
Повний текст джерелаChen, An-Yu, and 陳安妤. "Methods for Phage Assisted Autonomous Continuous Directed Evolution-PAACDE." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2rrhy9.
Повний текст джерелаLIN, MENG-YI, and 林孟逸. "Electrochemical Hydrogen Evolution Reaction Assisted by Time-Varying Magnetic Field." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f6yzp9.
Повний текст джерела明志科技大學
化學工程系碩士班
106
This study focused on alkaline water electrolysis to produce hydrogen gas in a varying magnetic field. The experiment used several electrodes, including platinum, FTO and TiO2/FTO. We used AFM and SEM to obtain the cathode surface morphology. It was found that the surface through blade coating were rough while that through spin coating were relatively flat. The electrolysis experiment shows that the impedance increased with applying a fixed magnetic field or a varying magnetic field. The production of hydrogen gas could be enhanced with increasing the frequency of the magnetic field. Furthermore, the change in current density corresponded to the desorption of hydrogen gas from the working electrode.
Chia-HaoHsu and 許佳豪. "Surrogate-Assisted Design Evolution with Censored Reliability Data in Engineering Design." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/04882834118190401921.
Повний текст джерелаLiu, Si-Ping, and 劉思屏. "Photocatalytic Hydrogen Evolution from SiO2@ZnIn2S4 Nanoparticles Synthesized Using Microwave-assisted Hydrothermal Method." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/70545259189340084302.
Повний текст джерела國立中央大學
化學工程與材料工程學系
104
Up to date, more and more evidences show that global warming and extreme weather conditions are associated with the CO2 level in atmosphere. Current energy supply and use do not be seen to reduce energy-related green-house-gas emission. Therefore, only changes in production and consumption path can decrease the dependence on fossil fuels. Developing low-carbon energy technologies is critical. Many agencies projected that the advances in hydrogen and fuel cell technologies can support climate change and energy security goals. In particular, hydrogen from renewable energies provides flexibility and sustainability for future low-carbon energy systems. ZnIn2S4 (ZIS) is a visible-light-driven photocatalyst with energy band gap of ~2.4 eV. In our previous work, we developed a microwave-assisted hydrothermal method to generate ZIS particles. The gold-silver nanoshells (GS-NS) with tunable absorption were embedded in ZIS matrix for plasmonic-enhanced photocatalytic hydrogen production. However, the coverage and thickness of ZIS on top of GS-NS were not precisely controlled. In this work, we focused on preparing SiO2@ZIS core-shell nanoparticles with tunable thickness of ZIS shells. Control over the core-shell particles enables us to study structure-property relations. Our experimental findings showed that the surface modification on SiO2 surfaces promoted nucleation of ZIS, leading to a homogeneous coverage. In addition, the thickness of ZIS shell can be easily tuned using microwave-assisted hydrothermal synthesis. Thus, our facile procedure paves the way to generate a more complex structure, GS-NS@dielectric@photocatalyst, for optimization of solar hydrogen production.
Li, Min-chih, and 黎閔智. "Microwave-assisted hydrothermal preparation of metal sulfide powder and photochemistry for hydrogen evolution." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/89346091428040318582.
Повний текст джерела國立中央大學
化學工程與材料工程學系
102
Energy crisis and environmental protection are big challenges of this century. Hydrogen is the most promising replacement for fossil fuels. Therefore, the development of visible-light-driven photocatalysts for water splitting is critical. The purpose of this study is to effectively use photocatalysts to change solar energy into hydrogen energy. We used ZIS (ZnmIn2S3+m) as visible-light-driven photocatalyst. Its water splitting reaction rate increased with the temperature. The absorption of the nanoshells in the coreshell nanoparticles can be adjusted systematically from visible light to IR range making the solar energy into heat and resulted in local thermal effect which can effectively enhance hydrogen evolution to 74%. Because the nanoshell was formed by silver and gold nanoparticles, it had the surface plasmon resonance. Using nanoshells absorbing at 700 nm can transfer enengy to photocatalysts and separated the combination of electrons and holes in photocatalysts making the enhancement of hydrogen evolution to 1.62 times. We also changed the thickness of SiO2 on the nanoshells to observe the interaction between nanoshells and coreshells which might influence the enhancement of hydrogen evolution. When there was no SiO2, electron would transfer between nanoshells and photocatalysts. Thicker thickness of SiO2 might hinder the translation of energy from nanoshells decreasing the enhancement of hydrogen evolution. Making photocatalysts directly into coreshell structures might cause thicker shell or uncovered nanoshells. So we try to mdify the surface of ZIS or mdify the surface of nanoshells and formed coreshell, making uniform distribution of ZIS on nanoshells.
Banks, Peter Robert. "Evolution and evaluation of a jet-assisted glow discharge source for atomic emission spectrometry." Thesis, 1992. http://hdl.handle.net/2429/2880.
Повний текст джерелаThanjavur, Karunananth G. "Cosmic applications of gravitational lens assisted spectroscopy (GLAS)." Thesis, 2008. http://hdl.handle.net/1828/1261.
Повний текст джерелаHuang, Yen-Chen, and 黃彥禎. "Improving Coverage and Crystallinity of SiO2@ZnIn2S4 Nanoparticles Using Microwave-assisted Hydrothermal Method for Photocatalytic Hydrogen Evolution." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/j4zmgm.
Повний текст джерела國立中央大學
化學工程與材料工程學系
106
Our society is facing growing challenges of energy and environment. In order to find clean and renewable energy resources instead of fossil fuels, many researchers worked hard and tried to find a way to solve the problem. Among these renewable energy resources, the biggest potential to develop is solar energy due to the endless of sun irradiation. To store the solar energy is another problem. One of the solutions is converting solar energy to chemical energy. So we use water-splitting photocatlyst to produce hydrogen under sun irradiation for energy storage. Hydrogen is a clean energy resource because it only produces water and energy after combustion. ZnIn2S4 (ZIS) is a visible-light-driven photocatalyst with the energy band gap of 2.4 eV. We developed a microwave-assisted hydrothermal method to generate ZIS particles. In particular, our studies showed that the gold-silver nanoshells with SiO2 shell(GSNS@SiO2) embedded in ZIS matrix exhibited a unique plasmonic-enhanced photocatalytic hydrogen production. However, the coverage and thickness of ZIS on top of GS-NS were not precisely controlled. If we improve the crystallinity and coverage of ZIS to control shell thickness of ZIS, we can find out the factor which could affect hydrogen production efficiency. Because GSNS@SiO2 is hard to synthesize, our research is focusing on SiO2 core instead of GSNS@SiO2. We found that SiO2@ZIS synthesized in pure water solution has better crystallinity, though synthesized in pure ethanol solution has better coverage. Adding HCl into both water and ethanol solution to lower pH condition would increase crystallinity, better crystallinity related to better hydrogen production efficiency. SiO2@ZIS synthesized in ethanol-water mixed solution would combine the advantage of two solutions, but the properties of the samples were too complex to analyze. Though ZIS shell could get thicker by repeating coating ZIS synthesized in different ratio of ethanol-water solution, not precisely controlling ZIS shell and only outer ZIS shell participating water-splitting reaction limited the use of repeating coating method. Finally we could increase crystallinity and coverage of SiO2@ZIS by adding HCl into pure ethanol solution, ZIS shell thickness could also be controlled by different concentration of ZIS precursor. However, due to the different properties between SiO2 core and GSNS@SiO2, it takes time to study SiO2@ZIS synthesis process applied to GSNS@SiO2. Thus, our facile procedure paves the way to generate a more complex structure GS-NS@dielectric@ photocatalyst, for optimization of solar hydrogen production.
Lin, Yu-Siou, and 林宇修. "Hydrogen Peroxide Assisted Hydrogen Evolution Reaction and Organic Dye Degradation Through Piezoelectricity of Highly Active Few-layered Td-WTe2 Microspheres." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f56k4k.
Повний текст джерелаLe, Roux Véronique. "Melt-rock interactions and melt-assisted deformation in the Lherz peridodite, with implications for the structural, chemical and isotopic evolution of the lithospheric mantle." Phd thesis, 2008. http://tel.archives-ouvertes.fr/tel-00431325.
Повний текст джерелаChung, Pei-Ju, and 鍾佩茹. "Seed-Mediated and Iodide-Assisted Synthesis of Gold Nanocrystals with Systematic Shape Evolution from Rhombic Dodecahedral to Octahedral Structures and Their Facet-Dependent Catalytic Activity." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/73636401484773315952.
Повний текст джерелаYoung, Carla Jo Logan. "Comparative Genomics of Gossypium spp. through GBS and Candidate Genes – Delving into the Controlling Factors behind Photoperiodic Flowering." Thesis, 2013. http://hdl.handle.net/1969.1/151335.
Повний текст джерела(10732359), Aaron Afriat. "COMBUSTION CHARACTERISTICS OF ADDITIVELY MANUFACTURED GUN PROPELLANTS." Thesis, 2021.
Знайти повний текст джерелаAdditive manufacturing of gun propellants is an emerging and promising field which addresses the limitations of conventional manufacturing techniques. Gun propellants are manufactured using wetted extrusion, which uses volatile solvents and dies of limited and constant geometries. On the other hand, additive techniques are faced with the challenges of maintaining the gun propellant’s energetic content as well as its structural integrity during high pressure combustion. The work presented in this thesis demonstrates the feasibility of producing functioning gun propellant grains using vibration-assisted 3D printing, a novel method which has been shown to extrude extremely viscous materials such as clays and propellant pastes. At first, the technique is compared to screw-driven additive methods which have been used in printing gun propellant pastes with slightly lower energetic content. In chapter two, diethylene glycol dinitrate (DEGDN), a highly energetic plasticizer, was investigated due to its potential to replace nitroglycerin in double base propellants with high nitroglycerin content. A novel isoconversional method was applied to analyze its decomposition kinetics. The ignition and lifetime values of diethylene glycol dinitrate were obtained using the new isoconversional method, in order to assess the safety of using the plasticizer in a modified double base propellant. In chapter three, a modified double base propellant (M8D) containing DEGDN was additively manufactured using VAP. The printed strands had little to no porosity, and their density was nearly equal to the theoretical maximum density of the mixture. The strands were burned at high pressures in a Crawford bomb and the burning was visualized using high speed cameras. The burning rate equation as a function of the M8D propellant as a function of pressure was obtained. Overall, this work shows that VAP is capable of printing highly energetic gun propellants with low solvent content, low porosity, with high printing speeds, and which have consistent burning characteristics at high pressures.
Crulli, Benjamin. "Evolution of diaphragmatic function in children under mechanical ventilation." Thesis, 2019. http://hdl.handle.net/1866/24006.
Повний текст джерелаIntroduction : Diaphragmatic dysfunction is highly prevalent in adult critical care and is associated with worse outcomes. There is at present no recognized method to assess diaphragmatic function in children under mechanical ventilation (MV) and no study describing its evolution over time in this population. Methods : In this work, we have assessed the contractile function of the diaphragm in children under invasive MV in the pediatric intensive care unit (PICU) and in the operating room (OR). This was done by simultaneously recording airway pressure at the endotracheal tube (Paw) and electrical activity of the diaphragm (EAdi) over consecutive spontaneous breaths during brief airway occlusion maneuvers. In order to account for central respiratory drive, a neuro-mechanical efficiency ratio (NME, Paw/EAdi) was first computed and then validated using variability analysis. Diaphragmatic function was then compared between the two populations and its evolution over time in the PICU group described. Results : Median NME was the most reliable measure of diaphragmatic function with a coefficient of variation of 23.7% and 21.1% in the PICU and OR groups, respectively. NME in the PICU group after 21 hours of MV (1.80 cmH2O/μV, IQR 1.25–2.39) was significantly lower than in the OR group (3.65 cmH2O/μV, IQR 3.45–4.24, p = 0.015). In the PICU group, NME did not decrease significantly over time under MV (correlation coefficient -0.011, p = 0.133). Conclusion : Diaphragmatic function can be measured at the bedside of children under MV using brief airway occlusions. Diaphragm efficiency was significantly higher in healthy controls than in a cohort of critically ill children, but it was stable over time under MV in this group with preserved respiratory drive. In the future, the relative contributions of critical illness and mechanical ventilation on diaphragmatic function should be better characterized before evaluating potential interventions aimed at protecting the diaphragm.
Neto, Acendino Alves da Silva. "Technological evolution in machining processes with CNC machines in the context of the concept of Industry 4.0." Master's thesis, 2018. http://hdl.handle.net/1822/57285.
Повний текст джерелаThe work related to the project of this dissertation will consist of an analysis of the technological evolution of the machining processes with CNC (Computer Numerical Control) machines regarding the new concept of Industry 4.0. The concept fits into the current transformation process for the fourth industrial revolution, such as integrated Cyber-Physical Systems (CPS) within the manufacturing processes using the Internet of Things (IoT) in industrial processes. Faced with technological advances, the processes of Industrial Engineering in machining using CNC machines must undergo adaptations, aiming at substantial increases in the operational effectiveness. Thus, an approach will be made to understand how current processes can adapt to the concept under study when analyzing the evolution of the machining tools for CNC machines in the face of new processes. A thorough study will be done to adapt the methodology of Industry 4.0 applying it to the machining processes in CNC Machines. Thereby, a proposal for future applications will be given on the topics studied. The methodology will be based entirely on a documental analysis research strategy. The virtual technology in machining tools is still a subject in development, being one of the main factors to be understood in this dissertation. In this study, it will be possible to analyze the main factors that can influence directly or indirectly the production processes of a factory with CNC machines. It will be explored and studied the types of machining processes for CNC machines and the types of machining tools developed with virtual technology. When we are talking about virtual technology, we are usually addressing the need for software. In CNC machining operations, there is a CAM (Computer Aided Manufacturing) software that performs machining simulations for CNC machines. Thus, a study and analysis of a production system involving a CAM software, a tool with virtual technology and CNC machines will be done to verify how this set can work encompassed and what changes this production model introduces. In the sequence of this study, an idea of a new production system will be proposed, allowing for a better understanding of the possibilities for application of new approaches in the future.
O trabalho relacionado ao projeto desta dissertação de mestrado consistirá de uma análise da evolução tecnológica dos processos de usinagem com as máquinas CNC (Comando Numérico Computacional) em relação ao novo conceito da Indústria 4.0. O conceito se enquadra no atual processo de transformação da quarta revolução industrial, com os Sistemas Ciber-Físicos integrados (CPS) dentro dos processos de fabricação que utilizam a Internet das Coisas (IoT) em processos industriais. Diante dos avanços tecnológicos, os processos de Engenharia Industrial em usinagem utilizando máquinas CNC devem sofrer adaptações, visando um aumento substancial na eficácia operacional. Assim, uma abordagem será feita para entender como os processos atuais podem se adaptar ao conceito em estudo, visando também uma análise da evolução das ferramentas de usinagem para máquinas CNC em face de novos processos. Um estudo minucioso será feito para adaptar a metodologia da Indústria 4.0, aplicando-a aos processos de usinagem em máquinas CNC. Com isso, algumas proposta para aplicações futuras serão apresentadas para os tópicos estudados. A metodologia será totalmente baseada em uma estratégia de investigação documental. A tecnologia virtual em ferramentas de usinagem ainda é um assunto em desenvolvimento, sendo um dos principais fatores a serem compreendidos na realização deste trabalho. Neste estudo, será possível analisar os principais fatores que podem influenciar direta ou indiretamente nos processos de produção de uma fábrica com máquinas CNC. Serão explorados e estudados os tipos de processos de usinagem para máquinas CNC e os tipos de ferramentas de usinagem desenvolvidas com tecnologia virtual. Quando abordamos o assunto sobre tecnologia virtual, geralmente estamos a lidar com a necessidade de um software. Nas operações de usinagem CNC, existe um software CAM (Manufatura Assistida por Computador) que realiza simulações de usinagem para máquinas CNC. Assim, um estudo e análise do sistema de produção envolvendo um software CAM, uma ferramenta com tecnologia virtual e máquinas CNC será feito para verificar como este conjunto pode trabalhar englobado e quais as mudanças para esse modelo de produção. Na sequência dessa análise, será proposta uma ideia de um novo sistema de produção, que permite uma melhor compreensão das possibilidades de aplicação no futuro das novas abordagens.