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1
Yan, Bo. "Active vibration isolation with a distributed parameter isolator." Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/51281/.
Повний текст джерелаАнотація:
Conventional vibration isolators are usually assumed to be massless for the purpose of modelling. This simplification tends to overestimate the isolator performance because of neglecting the internal resonances (IRs) due to the distributed mass effects in the isolator, which is especially important for lightly damped metallic isolators. Previous research on the problem of IRs is not particularly comprehensive, because it does not clarify the characteristics of the distributed parameter isolator. Furthermore, with the development of active vibration isolation, there is a need to investigate the effects of isolator IRs on the control performance and stability for commonly used control strategies. Effective ways to attenuate these effects are also required. This thesis concerns the active vibration isolation of a piece of delicate equipment mounted on a distributed parameter isolator, which is modelled as different idealised configurations under various types of deformation. The model is first developed to determine the effects of IRs on a single-degree-of-freedom system with a distributed parameter isolator. This analysis is then extended to include the resonance behaviour of the supporting structure. Simple expressions are derived which describe the behaviour of various types of distributed parameter isolator. The parameters which control the isolator performance at various frequencies are clarified theoretically and experimentally. The effects of IRs on control performance and stability of several control strategies are determined and compared. Absolute Velocity Feedback (AVF) control is shown to be the optimal solution to minimise the mean square velocity of the equipment mass supported by a distributed parameter isolator. A stability condition for an AVF control system containing a distributed parameter isolator is proposed. Based on this condition, different approaches to stabilize such a control system are presented. Experimental work is carried out to validate the theoretical results. Based on the improved knowledge of the characteristics of IRs in the distributed parameter isolator, different approaches which can suppress the IRs are proposed. AVF control with more damping in the isolator is demonstrated to be effective in attenuating the IRs theoretically and experimentally. Absolute velocity plus acceleration feedback control and AVF control on a fraction of the isolator length are also shown theoretically to be effective ways to attenuate the IRs and improve the isolation performance over a broad range of frequencies.
2
McCracken, Hollis B. "Isolation." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5500.
Повний текст джерелаАнотація:
My work investigates a lifelong passion for buildings, homes, and architecture. Buildings are more then shelters made of wood and screws; I personify them as if they were living breathing creatures. I’m particularly drawn to rundown and abandoned structures because I empathize with these sad looking buildings that were once majestic. This personal connection exists because I view them as versions of my former self, rough around the edges with a promising interior. Expanding beyond vacant and decaying buildings, I portray my experiences within fabricated architectural systems. I communicate with building materials and architecture through their many layers of physical and socially constructed histories. Drawing from my memories and feelings surrounding my brother’s death and subsequent drug addiction, I’ve focused on the emotions of abandonment, isolation, absence, and loneliness.
3
Iredale, Adrian Steven, and i@iredalepedersenhook com. "Constructed Isolation." RMIT University. Architecture & Design, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090505.155318.
Повний текст джерелаАнотація:
Constructed Isolation investigates the development of a collection of architectural devices and operations that respond to and have evolved from the specific nature of residential suburban Perth, Western Australia. These devices explore the potential for ambiguity to create space that transforms the occupant from being a passive observer into a dynamic participant. It collates a collection of projects by iredale pedersen hook architects and examines the devices under the thematic concerns of geometry, place, time and craft. The Masters Thesis identifies the potential for Perth's geographic isolation to manifest as a positive construct, developing a unique architecture that opportunistically reinterprets past traditions to create individual environments. 'Constructed Isolation' is an ambitious idea where identity may begin with the individual dwelling and collectively evolve to create a constellation of considerable influence. It demonstrates how these devices may result in new propositions for suburbia, how big ideas with small-scale projects and a little irrational joyousness may contribute to or at least aspire to create change. These small projects will be viewed as a continuation of Perth's 'Heroic Period of Modernism', the fertile and ambitious but incomplete project from the 1950s and '60s. This will also focus on the development and change that occurred as a result of the reflective practice process, while identifying potential opportunities for the future.
4
Aslam, Muzammil. "Percieved Isolation." Thesis, Mittuniversitetet, Avdelningen för design, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-31159.
Повний текст джерелаАнотація:
The concept of isolation has been used throughout history and has a negative connotation for humans. Isolation was often used for years, exemplified by tuberculosis sanitariums and leper colonies which ment social stigmatization. Humans are social animals whose behavior is determined by their needs and reactions to other people. This social aspect of huma existence is nowhere more evident than when he or she is isolated from others.
5
Ghymn, Eugene. "Isolation play." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1456997.
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6
Allen, Rebecca. "Isolation vs. interaction." This title; PDF viewer required Home page for entire collection, 2007. http://archives.udmercy.edu:8080/dspace/handle/10429/9.
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7
Duran, Cihan Kurtulus. "Seismic Roof Isolation Of Halkapinar Gymnasium." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12609008/index.pdf.
Повний текст джерелаАнотація:
In this study, seismic roof isolation solutions were investigated with a case study of Halkapinar Gymnasium, izmir. In the first part, seismic isolation was explanied and philosophy behind it was given. In the second part, existing seismic roof isolators, elastomeric bearing and viscous damper, were investigated with different support isolation combinations. In the third part, two more types of seismic isolators, lead rubber bearing and friction pendulum isolators, were also analyzed by using the same model and all results were compared with each other and that of non-isolated roof system. Furthermore, bilinear effect of the non-linear isolators were also studied. Finally, all results were compared with each other considering structure responses and effectiveness of the seismic isolators. It has been tried to find the most efficient seismic isolation solution for Halkapinar Gymnasium.
8
Sciulli, Dino. "Dynamics and Control for Vibration Isolation Design." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30511.
Повний текст джерелаАнотація:
The single-degree-of-freedom (SDOF) system is the most widely used model for vibration isolation systems. The SDOF system is a simple but worthy model because it quantifies many results of an isolation system. For instance, a SDOF model predicts that the high frequency transmissibility increases when the isolator has passive damping although this does not occur for an isolator implementing active damping. A severe limitation of this system is that it cannot be used when the base and/or equipment are flexible. System flexibility has been considered in previous literature but the flexibility has always been approximated which leads to truncation errors. The analysis used in this work is more sophisticated in that it can model the system flexibility without the use of any approximations. Therefore, the true effects of system flexibility can be analyzed analytically.
Current literature has not fully explored the choice of mount frequency or actuator placement for flexible systems either. It is commonly suggested that isolators should be designed with a low-frequency mount. That is, the isolator frequency should be much lower than any of the system frequencies. It is shown that these isolators tend to perform best in an overall sense; however, mount frequencies designed between system modes tend to have a coupling effect. That is, the lower frequencies have such a strong interaction between each other that when isolator damping is present, multiple system modes are attenuated. Also, when the base and equipment are flexible, isolator placement becomes a critical issue. For low-frequency mount designs, the first natural frequency can shift as much as 15.6% for various isolator placements.
For a mid-frequency mount design, the shift of the first three modes can be as high as 34.9%, 26.6% and 11.3%, respectively, for varying isolator placements.
NOTE: (03/2011) An updated copy of this ETD was added after there were patron reports of problems with the file.<br>Ph. D.
9
Christmas, P. "Isolation of endocytic compartments." Thesis, University of Liverpool, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233829.
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McKinnell, Robert James. "Active isolation of vibration." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306465.
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11
Ching, Kenneth A. (Kenneth Apostol). "Base isolation case study." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43889.
Повний текст джерелаАнотація:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.<br>Includes bibliographical references (leaf 51).<br>The primary objective of this thesis is the introduction of the current code, ASCE 7-05 into the base isolation design and the analysis of base isolation response due to seismic forces. An eight story irregular structure is modeled using SAP2000 structural program. The time history of Northridge earthquake is used as a seismic forcing function of the structure. The base isolator is designed by using the principle of bilinear modeling. Therefore, the base isolation system is analyzed using the non-linear time history analysis. The response of the isolation system is analyzed, and especially its hysteresis loop. Results show that the inputted energy of the seismic forces is dissipated by hysteretic and modal damping.<br>by Kenneth A. Ching.<br>M.Eng.
12
Ballantyne, Brant Francis 1974. "Seismic isolation of bridges." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80632.
Повний текст джерелаАнотація:
Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.<br>Includes bibliographical references (leaves 41-42).<br>by Brant Francis Ballantyne.<br>M.Eng.
13
Smith, Morgan Inigo. "Flotsam: Men in Isolation." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1505213/.
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14
Bersch, Danielle. "A Promenade for Isolation." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23673.
Повний текст джерелаАнотація:
This building emerges as a solitary work from obscurity. Its form is a composition of disjointed rooms connected by common themes: frontality, obscurity, artifice, and seclusion.<br /><br />In the first part, the plan appears as a map of a promenade which is the main ordering device of the building structure.<br /><br />In the second part, the internal spaces are presented as isolated from each other as is the building from any external reference.<br /><br />In the sections, which constitute the third part, the building appears as layered facades emerging from planes of strata.<br>Master of Architecture
15
Vilanova, García Lluís. "Code-Centric Domain Isolation : a hardware/software co-design for efficient program isolation." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/385746.
Повний текст джерелаАнотація:
Current software systems contain a multitude of software components: from simple libraries to complex plugins and services. System security and resiliency depends on being able to isolate individual components onto separate domains.
Conventional systems impose large performance and programmability overheads when isolating components. Importantly, when performance and isolation are at stake, performance often takes precedence at the expense of security and reliability.
These performance and programmability overheads are rooted at the co-evolution of conventional architectures and OSs, which expose isolation in terms of a loose "virtual CPU" model. Operating Systems (OSs) expose isolation domains to users in the form of processes. The OS kernel is isolated from user code by running at a separate privileged level. At the same time, user processes are isolated from each other through the utilization of different page tables. The OS kernel then multiplexes processes across the available physical resources, providing processes the illusion of having a machine for their exclusive use. Given this virtual CPU model, processes interact through interfaces designed for distributed systems, making their programming and performance poorer.
The architectural foundations used for building processes impose performance overheads in the excess of 10× and 1000× compared to a function call (for privilege level and page table switches, respectively). Even more, not all overheads can be attributed to the hardware itself, but to the inherent overheads imposed by current OS designs; the OS kernel must mediate cross-process communications through expensive Inter-Process Communication (IPC) operations, which deviate from the traditional synchronous function call semantics. Threads are bound to their creating process, and invoking functionality across processes requires costly OS kernel mediation and application developer involvement to synchronize and exchange information through IPC channels.
This thesis proposes a hardware and software co-design that eliminate the overheads of process isolation, while providing a path for gradual adoption for more aggressive optimizations. That is, it allows processes to efficiently call into functions residing on other isolation domains (e.g., processes) without breaking the synchronous function call semantics. On the hardware side, this thesis proposes the CODOMs protection architecture. It provides memory and privilege protection across software components in a way that is at the same time very efficient and very flexible. This hardware substrate is then used to propose DomOS, a set of changes to the OS at the runtime and kernel layers to allow threads to efficiently and securely cross process boundaries using regular function calls. That is, a thread in one process is allowed to call into a function residing in another process without involving the OS in the critical communication path. This is achieved by mapping processes into a shared address space and eliminating IPC overheads through a combination of new hardware primitives and compile-time and run-time optimizations.
IPC in DomOS is up to 24× times faster than Linux pipes, and up to 14× times faster than IPC in L4 Fiasco.OC. When applied to a multi-tier web server, DomOS performs up to 2.18× better than an unmodified Linux system, and 1.32× on average. On all configurations, DomOS provides more than 85% of the ideal system efficiency.<br>Els sistemes software d'avui en dia contenen una multitud de components software: des de simples llibreries fins a plugins o serveis complexos. La seguretat i fiabilitat d'aquests sistemes depèn de ser capaç d'aïllar cadascun d'aquests components en un domini a part. L'aïllament en els sistemes convencionals imposa grans costos tant en el rendiment com en la programabilitat del sistema. És més, tots els sistemes solen donar prioritat al rendiment sobre qualsevol altre consideració, degradant la seguretat i fiabilitat del sistema. Aquests costos en rendiment i programabilitat són deguts a la co-evolució de les arquitectures i Sistemes Operatius (SOs) convencionals, que exposen l'aïllament en termes d'un model de "CPUs virtuals". Els SOs encarnen aquest model a través dels processos que proprcionen. El SO s'aïlla del codi d'usuari a través d'un nivell de privilegi separat. Al mateix temps, els processos d'usuari estan aïllats els uns dels altres al utilitzar taules de pàgines separades. El nucli del SO multiplexa aquests processos entre els diferents recursos físics del sistema, proporcionant-los la il·lusió d'estar executant-se en una màquina per al seu ús exclusiu. Donat aquest model, els processos interactuen a través d'interfícies que han estat dissenyades per a sistemes distribuïts, empitjorant-ne la programabilitat i rendiment. Els elements de l'arquitectura que s'utilitzen per a construïr processos imposen costos en el rendiment que superen el 10x i 1000x en comparació amb una simple crida a funció (en el cas de nivells de privilegi i canvis de taula de pàgina, respectivament). És més, part d'aquests costos no vénen donats per l'arquitectura, sinó pels costos inherents al disseny dels SOs actuals. El nucli del SO actua com a mitjancer en la comunicació entre processos a través de primitives conegudes com a IPC. El IPC no és només costós en termes de rendiment, sinó que a més a més es desvia de les semàntiques tradicionals de crida síncrona de funcions. Tot "thread" està lligat al procés que el crea, i la invocació de funcionalitat entre processos requereix de la costosa mediació del SO i de la participació del programador a l'hora de sincronitzar "threads" i intercanviar informacio a través dels canals d'IPC. Aquesta tesi proposa un co-disseny del programari i del maquinari que elimina els costos de l'aïllament basat en processos, alhora que proporciona un camí per a l'adopció gradual d'optimitzacions més agressives. És a dir, permet que qualsevol procés faci una simple crida a una funció que està en un altre domini d'aïllament (com ara un altre procés) sense trencar la la semàntica de les crides síncrones a funció. Aquesta tesi proposa l'arquitectura de protecció CODOMs, que proporciona protecció de memòria i privilegis entre components de programari d'una forma que és, alhora, eficient i flexible. Aquest substrat del maquinari és aleshores utilitzat per proposar DomOS, un conjunt de canvis al SO al nivell del "runtime" i del nucli que permeten a qualsevol "thread" fer crides a funció de forma eficient i segura a codi que resideix en d'altres processos. És a dir, que el "thread" d'un procés pot cridar una funció d'un altre procés sense haver de passar pel SO en el seu camí crític. Això s'aconsegueix a través de mapejar tots els processos en un espai d'adreces compartit i d'eliminar tots els costos d'IPC a través d'una combinació de noves primitives en el maquinari i d'optimitzacions en temps de compilació i en temps d'execució. El IPC a DomOS és fins a 24x més ràpid que les pipes a Linux, i fins a 14x més ràpid que el IPC al SO L4 Fiasco.OC. Si s'aplica el sistema a un servidor web multi-capa, DomOS és fins a 2.18x més ràpid que un sistema Linux no modificat, i 1.32x més ràpid de mitjana. En totes les configuracions, DomOS proporciona més del 85% de la eficiència d'un sistema ideal.
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Yawger, Geneva Carolyn. "Social Isolation Predicting Problematic Alcohol Use in Emerging Adults: Examining the Unique Role of Existential Isolation." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/852.
Повний текст джерелаАнотація:
Current rates of excessive alcohol use and abuse among young adults are recognized as a major problem by scholars across a wide variety of fields. Here, I take a social psychological approach to understanding why individuals drink to excess, examining the unique role that a specific form of social isolation called existential isolation (feeling alone in one’s experiences of the world; Yalom, 1980; Pinel, Long, Murdoch, & Helm, 2017) may play in predicting alcohol use and abuse. The relationship between existential isolation and alcohol use is explored using both correlational and cross-lagged designs. Results indicate that existential isolation predicts alcohol use above and beyond a more traditional measure of social isolation, though not in the hypothesized direction (i.e. social isolation is associated with more alcohol use, whereas existential isolation is associated with less). Further, negative emotional symptoms (depression, anxiety, and stress) and racial identity emerged as significant moderators of this effect. Exploratory analyses considering a reversal of the hypothesized causal direction (i.e. alcohol use now predicting feelings of existential isolation) revealed a significant two-way interaction between current and lifetime alcohol use and a significant three-way interaction between current alcohol use, desire for existential connection, and motivations to use alcohol for social purposes. Implications of these general findings are discussed, including that 1) they identify a seemingly positive outcome of drinking that may play a role in perpetuating problematic alcohol use, and 2) conversely, they may illustrate a “dark side of sobriety.” This research serves as a first step into distinguishing between aspects of social isolation in the realm of alcohol use and abuse. Future research is necessary in order to identify the mechanisms underlying this effect and inform the development of more effective alcohol-related interventions.
17
Taduri, Rahul Ramachandra. "Effect of Material Properties and Geometric Scaling on Static and Dynamic Stiffness of an Exhaust Isolator Bracket Design." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1432310663.
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18
Thurén, Mårten. "Fault Isolation By Manifold Learning." Thesis, Linköping University, Vehicular Systems, 1985. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57547.
Повний текст джерелаАнотація:
<p>This thesis investigates the possibility of improving black box fault diagnosis by a process called manifold learning, which simply stated is a way of finding patterns in recorded sensor data. The idea is that there is more information in the data than is exploited when using simple classification algorithms such as k-Nearest Neighbor and Support Vector Machines, and that this additional information can be found by using manifold learning methods. To test the idea of using manifold learning, data from two different fault diagnosis scenarios is used: A Scania truck engine and an electrical system called Adapt. Two linear and one non-linear manifold learning methods are used: Principal Component Analysis and Linear Discriminant Analysis (linear) and Laplacian Eigenmaps (non-linear).Some improvements are achieved given certain conditions on the diagnosis scenarios. The improvements for different methods correspond to the systems in which they are achieved in terms of linearity. The positive results for the relatively linear electrical system are achieved mainly by the linear methods Principal Component Analysis and Linear Discriminant Analysis and the positive results for the non-linear Scania system are achieved by the non-linear method Laplacian Eigenmaps.The results for scenarios without these special conditions are not improved however, and it is uncertain wether the improvements in special condition scenarios are due to gained information or to the nature of the cases themselves.</p>
19
Kvalø, Tarjei Olsen. "Reliability of Ignition Source Isolation." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10934.
Повний текст джерелаАнотація:
<p>This thesis work was a study into how the effectiveness of ignition source isolation can be estimated. This safety system works by isolating electrical equipment from power when flammable gas is detected on oil and gas installations. Improving the understanding of how effective this system actually is at reducing explosion risk in hazardous areas was the main motivation, as this could help operators and authorities form a more accurate risk picture. The main part of the work is the development and discussion of a model for ignition that was made so that it could be used to estimate this effectiveness. A detailed model is presented first, based on evaluating failure modes of equipment, then suggestions are made for how it could be simplified to be of practical use in risk analysis. The second part of the project was to gather enough data from industry sources to be able to estimate key parameters in the model relating to the failure probability of Ex barriers and the ignition probability resulting from common types of process equipment. Not enough data was found to support a quantification of these parameters, but results from a major maintenance project on an oil and gas installation in the Norwegian sector was reviewed and discussed. The method of systematically evaluating failure modes in order to determine risk could be useful in other applications, and the suggested way to proceed with the work in this report is to continue gathering data and analyzing it to build up a credible set of failure probabilities for Ex barriers and common equipment types.</p>
20
Mansour, Mohamed S. "Behavior Isolation in Enterprise Systems." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14613.
Повний текст джерелаАнотація:
A barrier to creating the platform-independent services envisioned by middleware-based development infrastructures is the level of performance robustness of the distributed applications created with them, in lieu of unpredictable variations in application behavior or in the resources available for satisfying user requests. Our goal is to improve the behavior locality of distributed applications and to prevent performance (mis-)behaviors from spilling across certain boundaries, since such spillage weakens behavior diagnoses and/or weakens or disables the effects of locally applied control or management methods. Toward these ends, we develop a novel software abstraction, termed {em isolation points} (I-points), which can be used to isolate application components or subsystems from each other.
The main contributions of this work are Isolation Points, which are software abstractions for monitoring and understanding dynamic runtime behaviors to better isolation application components hence creating more robust distributed applications. Two concrete artifacts using I-points also developed in this thesis are: I(solation)-RMI and I(solatoin)-Queue. I-RMI demonstrates the utility of isolation points in J2EE's RMI-IIOP domain. I(solation)-Queue applies isolation points to message passing systems.
21
Zetterström, Susanna. "Isolation and synthesis of curcumin." Thesis, Linköpings universitet, Organisk Kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-84509.
Повний текст джерелаАнотація:
The aim of this thesis was to evaluate pre-existing methods for isolation and synthesis of curcumin. Two different isolation methods were used, where only the extraction step differs from each other. To obtain pure curcumin, column chromatography was needed to separate the compound from its analogues. As for the isolation the synthesis was also carried out by two different methods, the first in a conventional way and the second one by using irradiation of microwaves. The result of the experiments shows that by comparing the effectiveness and expense of the methods, the synthesis would probably be the easiest way of obtaining pure compound. Because of the more straightforward method, without cumbersome separation steps from the curcumin analogues, the synthesis was a faster way of obtaining the compound and gave more pure curcumin than the isolation procedures from turmeric.
22
Bonn, M. "Social isolation in the playground." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383702.
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Pilling, Adam Wesley. "Site Isolation in Cyclisation Cascades." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492762.
Повний текст джерелаАнотація:
This thesis concerns the exploitation of the site isolation concept in cascade sequences that facilitate rapid construction of complex polycyclic molecules. Site isolation is the anchoring of mutually destructive reagents onto solid supports to prevent their mutual deactivation.
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Irvine, Andrew R. "Isolation and the parish ministry." Thesis, University of St Andrews, 1989. http://hdl.handle.net/10023/2626.
Повний текст джерелаАнотація:
The purpose of this thesis was to examine the concept of isolation as it occurs within the profession of ministry. Isolation, for the purpose of this thesis, is defined social-psychologically. Within the field research isolation is considered as evidenced professionally, socially and spiritually. This study utilized as its sample base 200 hundred Church of Scotland ministers (15% of total population) which provided 159 usable responses to an extensive mail survey. The mail survey consisted of a questionnaire designed and tested to measure experienced isolation; the Myers-Briggs Type Indicator, a personality measure; and the Purpose In Life Test, a measure of motivation. A further 15% of the respondents were selected by random process for direct interviews. The thesis is divided into four primary sections; psychological perspective, theological perspective , field research, summary and conclusions. Chapter 1 reviews eight psychological perceptions of isolation as found in the works of such notables as Freud, Adler, Fromm, Horney, Laing, Sullivan, and Frankl. From these it was determined that common to all perspectives of isolation was a primary isolation from the SELF. In chapters 2 and 3a model of isolation was developed from the work of C. G. Jung and applied to the profession of ministry. Chapters 4 to 6 examine the concept of separation from the self from a theological perspective as found in the works of P. Tillich and E. Brunner. Chapter 6 develops a composite view of the self and considers it in light of the redemptive process. Chapters 7 to 10 review the actual field study conducted by the researcher among the Church of Scotland ministers. This study concludes in Chapter 11 with a summary of the findings and their implications for the ministry of the church. The salient factor evidenced was that isolation is not primarily an inter-relational problem, but rather an intrarelational phenomenon.
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Ahmed, Shuja. "Implant isolation of gallium arsenide." Thesis, University of Surrey, 2002. http://epubs.surrey.ac.uk/804438/.
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Baumforth, Karl Robert Nicholas. "Isolation and characterisation of mannosomes." Thesis, University of Wolverhampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300751.
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Hall, Zachary (Zachary H. ). "Photon isolation and jet substructure." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120219.
Повний текст джерелаАнотація:
Thesis: S.B., Massachusetts Institute of Technology, Department of Physics, 2018.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 41-45).<br>We introduce soft drop isolation, a new photon isolation criterion inspired by jet substructure techniques. Soft drop isolation is collinear-safe and is equivalent to Frixione isolation at leading order in the small R limit. However, soft drop isolation has the interesting feature of being democratic, meaning that photons can be treated equivalently to hadrons for initial jet clustering. Taking advantage of this democratic property, we define an isolated photon subjet: a photon that is not isolated from its parent jet but is isolated within its parent subjet after soft drop declustering. The kinematics of this isolated photon subjet can be used to expose the QED splitting function, in which a quark radiates a photon, and we verify this behavior using both a parton shower generator and a perturbative calculation in the collinear limit.<br>by Zachary Hall.<br>S.B.
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Manarbek, Saruar. "Study of base isolation systems." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82820.
Повний текст джерелаАнотація:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2013.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 55-56).<br>The primary objective of this investigation is to outline the relevant issues concerning the conceptual design of base isolated structures. A 90 feet high, 6 stories tall, moment steel frame structure with tension cross bracing is used to compare the response of both fixed base and base isolated schemes to severe earthquake excitations. Techniques for modeling the superstructure and the isolation system are also described. Elastic time-history analyses were carried out using comprehensive finite element structural analysis software package SAP200. Time history analysis was conducted for the 1940 El Centro earthquake. Response spectrum analysis was employed to investigate the effects of earthquake loading on the structure. In addition, the building lateral system was designed using the matrix stiffness calibration method and modal analysis was employed to compare the intended period of the structure with the results from computer simulations. Base isolation proves to be effective in reducing the induced inertia forces on a structure by increasing the effective period of oscillation. Keywords: Base Isolation, time history analysis, response spectrum analysis, matrix stiffness calibration method.<br>by Saruar Manarbek.<br>M.Eng.
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Behrens, Diogo. "Error isolation in distributed systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-203428.
Повний текст джерелаАнотація:
In distributed systems, if a hardware fault corrupts the state of a process, this error might propagate as a corrupt message and contaminate other processes in the system, causing severe outages. Recently, state corruptions of this nature have been observed surprisingly often in large computer populations, e.g., in large-scale data centers. Moreover, since the resilience of processors is expected to decline in the near future, the likelihood of state corruptions will increase even further.
In this work, we argue that preventing the propagation of state corruption should be a first-class requirement for large-scale fault-tolerant distributed systems. In particular, we propose developers to target error isolation, the property in which each correct process ignores any corrupt message it receives.
Typically, a process cannot decide whether a received message is corrupt or not. Therefore, we introduce hardening as a class of principled approaches to implement error isolation in distributed systems. Hardening techniques are (semi-)automatic transformations that enforce that each process appends an evidence of good behavior in the form of error codes to all messages it sends. The techniques “virtualize” state corruptions into more benign failures such as crashes and message omissions: if a faulty process fails to detect its state corruption and abort, then hardening guarantees that any corrupt message the process sends has invalid error codes. Correct processes can then inspect received messages and drop them in case they are corrupt.
With this dissertation, we contribute theoretically and practically to the state of the art in fault-tolerant distributed systems. To show that hardening is possible, we design, formalize, and prove correct different hardening techniques that enable existing crash-tolerant designs to handle state corruption with minimal developer intervention. To show that hardening is practical, we implement and evaluate these techniques, analyzing their effect on the system performance and their ability to detect state corruptions in practice.
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Ledezma, Ramirez Diego Francisco. "Shock isolation using switchable stiffness." Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/64538/.
Повний текст джерелаАнотація:
This study investigates a novel stiffness control strategy applied to the problem of shock isolation. This is based on the principle that the stiffness and mass are the principal physical properties that control the passive system shock response. The problem of shock response control is divided in two stages. Firstly, the maximum response whilst a shock is applied is considered, and the effectiveness of a switchable isolation stiffness strategy is evaluated. This strategy aims to reduce the shock response by switching the stiffness to a low value during the shock input. Two different models are considered for the theoretical analysis, namely, a single mass supported by two elastic elements one of which can be disconnected, and a second model where the switchable element comprises a secondary mass-stiffness system. The performance of the two strategies is analyzed in terms of response parameters such as the absolute and relative displacement and absolute acceleration. The single degree-of-freedom system is considered as a benchmark for comparison. The issue of residual vibration suppression is then presented. For the latter a different switchable stiffness strategy is identified, and the analysis is mainly concerned with the energy dissipation mechanism used to suppress residual vibration. As in the first stage of shock isolation, two models are considered. Optimum configurations and stiffness changes are identified for both the shock response reduction and the decay of the residual vibration. The effect of viscous damping is subsequently incorporated. The practical implementation and experimental validation is then presented and a experimental system is developed. It is based on a conceptual model comprising a magnetic suspension element that is able to change its effective stiffness by altering the magnetic force. This novel configuration has the advantages of achieving a high stiffness change in a very short amount of time and with very low damping, which is required to validate the theoretical studies. The design and properties of the model are discussed and then both stiffness strategies are implemented. This model is used to show the feasibility and evaluate the isolation performance of the different switchable stiffness strategies and the issues and limitations of the implementation.
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Vannier, Philippe. "Isolation active d'un moteur d'avion." Ecully, Ecole centrale de Lyon, 1994. http://bibli.ec-lyon.fr/exl-doc/TH_T1552_pvannier.pdf.
Повний текст джерелаАнотація:
Le confort dans les moyens de transport devient un atout commercial majeur de la fin du 20ieme siècle. Pour compenser l'optimisation statique des structures qui avive les problèmes en dynamique, des solutions passives ont été utilisées. Elles atteignent maintenant leurs limites. Une nouvelle ouverture intéressante se manifeste grâce au contrôle actif. Ce travail portera sur la mise en œuvre des concepts de contrôle actif sur des structures de portée industrielle. Cette étude, en relation avec la société motoriste aéronautique française, Snecrna, proposera une première étude de faisabilité destinée à optimiser la position des actionneurs compte tenu des impératifs structuraux. On pourra ainsi étudier sur un modèle d'ensemble propulsif les efforts nécessaires au contrôle dans un cas idéal en rapport avec la ou les sources de perturbation. Après cette étude de faisabilité, nous montrerons sur un banc d'essai de structure massive la réelle application du contrôle actif. Tout d'abord, les simulations permettent d'évaluer le problème. Ensuite, la mise en oeuvre expérimentale du contrôle s'effectue via des servovérins hydrauliques et inclue les boucles d'acquisition, de filtrage et de contrôle numérique. Ces études expérimentales sont riches d'enseignement pour une éventuelle industrialisation<br>Comfort in means of transport becomes a greatest commercial asset of the end of the 20th century. To compensate structural optimisation tliat stirs up problems in dynamic, passive solutions have been used. Thèse solutions have reached their limits. An interesting new overture could be structural active control. This work is focused on the implementation of active control concepts on structures with industrial sizes. This study, that bears relations to the French aircraft engine society, Snecma, will firstly propose a feasibility study to optimise actuators position, considering structural requirements. We could then study the strains required for the control in an idéal case, in regard with the disturbance source. After tins feasibility study, we'll show on a test bed, with a massive structure the true application of active control. First of ail, simulations allow to assess the problem. Then, the experimental implementation of control is made thanks to hydraulic servo-jacks, with acquisition, filtering and numerical control loops. Thèse expérimental studies teach many useful things for a possible industrialisation
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Lenat, Yves. "Isolation dynamique expérimentation et modélisation." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37599112h.
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Cahill, Michael James. "Serializable Isolation for Snapshot Databases." Thesis, The University of Sydney, 2009. http://hdl.handle.net/2123/5353.
Повний текст джерелаАнотація:
Many popular database management systems implement a multiversion concurrency control algorithm called snapshot isolation rather than providing full serializability based on locking. There are well-known anomalies permitted by snapshot isolation that can lead to violations of data consistency by interleaving transactions that would maintain consistency if run serially. Until now, the only way to prevent these anomalies was to modify the applications by introducing explicit locking or artificial update conflicts, following careful analysis of conflicts between all pairs of transactions. This thesis describes a modification to the concurrency control algorithm of a database management system that automatically detects and prevents snapshot isolation anomalies at runtime for arbitrary applications, thus providing serializable isolation. The new algorithm preserves the properties that make snapshot isolation attractive, including that readers do not block writers and vice versa. An implementation of the algorithm in a relational database management system is described, along with a benchmark and performance study, showing that the throughput approaches that of snapshot isolation in most cases.
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Cahill, Michael James. "Serializable Isolation for Snapshot Databases." University of Sydney, 2009. http://hdl.handle.net/2123/5353.
Повний текст джерелаАнотація:
PhD<br>Many popular database management systems implement a multiversion concurrency control algorithm called snapshot isolation rather than providing full serializability based on locking. There are well-known anomalies permitted by snapshot isolation that can lead to violations of data consistency by interleaving transactions that would maintain consistency if run serially. Until now, the only way to prevent these anomalies was to modify the applications by introducing explicit locking or artificial update conflicts, following careful analysis of conflicts between all pairs of transactions. This thesis describes a modification to the concurrency control algorithm of a database management system that automatically detects and prevents snapshot isolation anomalies at runtime for arbitrary applications, thus providing serializable isolation. The new algorithm preserves the properties that make snapshot isolation attractive, including that readers do not block writers and vice versa. An implementation of the algorithm in a relational database management system is described, along with a benchmark and performance study, showing that the throughput approaches that of snapshot isolation in most cases.
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Lee, Junyi. "Vibration isolation with periodic structures." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/33338.
Повний текст джерелаАнотація:
Vibrations are undesirable and cause many problems in engineering. Among the many techniques to reduce vibrations, phononic crystals and elastic metamaterials, that have periodic variations in geometry or material properties, have the potential to attenuate vibrations over a large range of frequencies. These classes of materials attenuate vibrations via the band gap mechanism that stops elastic waves from propagating. Additionally, periodic structures can possess high effective stiffness or strength to density ratios. This makes them ideal for lightweight structural applications. Furthermore, their periodic nature allows band gaps to be generated in them. These features can be combined to produce lightweight structural components with vibration isolation properties. Currently, very few studies of this class of materials for practical applications were made. Therefore, the goal of the work done in this thesis is to develop techniques and perform analyses to promote their implementation. A literature review has been performed on the techniques to determine the band structures and effective properties of lattice materials. A novel method coined the wave superposition method (WSM) to measure the band structure was developed. This method allows band structures to be determined experimentally using simple equipment with a small number of measurements. The method was then validated experimentally. A parametric study on the mechanical and dispersion properties of cubic lattice structures were conducted to assess the viability of designing a multifunctional lattice structure with excellent properties to be used as multifunctional lightweight and vibration attenuating components. Important trends relating to the geometric parameters to the performance of the lattice structures were found. Lastly, an experimental study was performed on a selected design to demonstrate the vibration attenuation characteristic of this material. The techniques and findings in this thesis, have laid the foundations for future development of periodic structures for both structural and vibration isolation applications.
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Delport, Waldo. "Forensic evidence isolation in clouds." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/33490.
Повний текст джерелаАнотація:
Cloud computing is gaining acceptance and also increasing in
popularity. Organisations often rely on cloud resources as an
effective replacement for their `in-house' computer systems. In the
cloud, virtual resources are provided from a larger pool of resources,
these resources being available to multiple different clients.
When something suspicious happens within a digital environment, a
digital forensic investigation may be conducted to gather information
about the event. When conducting such an investigation digital
forensic procedures are followed. These procedures involve the steps
to be followed to aid in the successful completion of the
investigation. One of the possible steps that may be followed involves
isolating possible evidence in order to protect it from contamination
and tampering.
Clouds may provide a multi-tenancy solution across multiple
geographical locations. When conducting an investigation into physical
equipment the equipment may be isolated. This may be done, for
example, by placing a cell phone in a Faraday bag in order to block
signals or unplugging a computer's network cable to stop the computer
from either sending or receiving of network traffic. However, in the
cloud it may not be applicable to isolate the equipment of the cloud
because of the multi-tenancy and geographically separated nature of
the cloud. There is currently little research available on how
isolation can be accomplished inside the cloud environment.
This dissertation aims at addressing the need for isolation on the
cloud by creating new methods and techniques that may be incorporated
into an investigation in order to isolate cloud resources. Isolation
can be achieved by moving the unnecessary evidence to a different
location and retaining the required evidence or by moving the required
evidence in such a manner that the evidence would not be contaminated.
If isolated evidence were to be moved to a digital forensic
laboratory, the question arises as to whether it would be possible to
create such a laboratory on the cloud utilise the benefits of cloud
computing and enable the investigation to be conducted on the cloud
without moving the isolated evidence from the cloud. The dissertation
will develop various models of isolation. These models are then tested
in experimental conditions. The experiments were conducted on Nimbula
Director 1.0.3 and VMware vSphere 5.0.
The models were successfully applied in the experiments. It was found
that investigations could benefit from the use of the proposed models
for isolation. However, the experiments also highlighted that some of
the models are not applicable or that a combination should be used.
The experiments also indicated that the methods to be used would
depend on the circumstances of the investigation. A preliminary "cloud
laboratory" was designed and described in terms of which a digital
forensic laboratory can be created on the cloud resources, thus
enabling an investigation to be conducted inside the cloud
environment.<br>Dissertation (MSc)--University of Pretoria, 2013.<br>Computer Science<br>unrestricted
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Tanner, Edward Troy. "Combined Shock and Vibration Isolation Through the Self-Powered, Semi-Active Control of a Magnetorheological Damper in Parallel with an Air Spring." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/29541.
Повний текст джерелаАнотація:
Combining shock and vibration isolation into a single isolation system package is explored through the use of an air spring in parallel with a controlled magnetorheological fluid damper. The benefits of combining shock and vibration isolation into a single package is discussed. Modeling and control issues are investigated and test and simulation results are discussed. It is shown that this hybrid isolation system provides significantly increased performance over current state-of-the-art passive systems. Also explored is the feasibility of scavenging and storing ambient shipboard vibration energy for use in powering the isolation system.
To date the literature has not adequately explored the direct design of a combined shock and vibration isolation system. As shock and vibration isolation are typically conflicting goals, the traditional approach has been to design separate shock and vibration isolation systems and operate them in parallel. This approach invariably leads to compromises in terms of the performance of both systems. Additionally, while considerable research has been performed on magnetorheological fluids and devices based on these fluids, there has been little research performed on the use of these fluids in devices that are subjected to high velocities such as the velocity seen by a ship exposed to underwater near-miss explosive events. Also missing from the literature is any research involving the scavenging and storage of ambient shipboard vibration energy. While the focus of this work is on the use of this scavenged energy to power the subject isolation system, many other uses for this energy can be envisioned.
Experimental and analytical results from this research clearly show the advantages of this hybrid isolation system. Drop tests show that inputs as great as 167 g's were reduced to 3.42 g's above mount at 1.11 inches of deflection using a Velocity Feedback controller suggested by the author. When contrasted with typical test results with similar inputs, the subject isolation system achieved reductions in above mount accelerations of 300% and reductions in mount deflections of 200% over current state-of-the-art passive shipboard isolation systems. Furthermore, simulations using a validated model of the isolation system suggest that this performance improvement can be achieved in multi-degree-of-freedom isolation systems as well. It was shown that above mount accelerations in the vertical and athwartship directions could be effectively limited to a predefined value, while achieving the absolute minimum mount defections, using an Acceleration Limiting Bang-Bang controller suggested by the author. Further experimentation suggests that the subject isolation system could be entirely self-powered from scavenged ambient shipboard vibration energy. An experiment using an energy scavenging and storage system consisting of a Piezoelectric Stack Generator and a bank of ultracapacitors showed that enough energy could be harvested to power the isolation system though several shock events.<br>Ph. D.
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Eriksson, Sandra. "Fönster med utsikt : Patienters upplevelse av att vårdas under isolering inom somatisk slutenvård." Thesis, Högskolan i Borås, Akademin för vård, arbetsliv och välfärd, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-14639.
Повний текст джерелаАнотація:
Inom sjukvården finns det två former av isolering. Smittskyddsisolering är till för att hindra smittspridning när en person blir smittad av en infektion som kan vara farlig för allmänheten och skyddsisolering används när en person är extra infektionskänslig, exempelvis efter cytostatikabehandling för cancer. Syftet med studien var att beskriva hur patienter upplever isoleringsvård inom den somatiska slutenvården. Vald metod var en litteraturstudie där åtta kvalitativa artiklar användes. Sex teman identifierades i resultatet: Behov av anhöriga, Behov av stöd från sjuksköterskan, Känsla av instängdhet, Behov av kontroll, Behovet av information och Känslan av frihet. Studien visade att isolering leder till känslor av ensamhet, känslan av övergivenhet, psykisk ohälsa och skam. Det visade sig att behovet av medmänsklig kontakt och information var av stor betydelse för patienter för att kunna hantera sin tid under isolering. Många beskrev att det inte bara var negativt att ha ett eget rum utan det gav känslor av ro och underlättade vid besök. Att ha tillgång till tv, telefon och internet var för patienterna olika sätt för att få stimulans och få tiden att gå, som annars kunde kännas långsam. Sjuksköterskan var ett viktigt stöd och en källa till medmänsklighet. Att ha ett fönster med utsikt över omgivningen gjorde upplevelsen mer uthärdlig för flertalet av patienterna.
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Bieniusa, Annette [Verfasser], and Peter [Akademischer Betreuer] Thiemann. "Consistency, isolation, and irrevocability in software transactional memory = Konsistenz, Isolation und Unwiderruflichkeit in Software Transactional Memory." Freiburg : Universität, 2011. http://d-nb.info/1114828998/34.
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Gabbianelli, Elena. "Layered periodic metafoundation for seismic isolation." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Знайти повний текст джерелаАнотація:
In the present thesis the dynamic response of two structures with different foundation, in particular the periodic foundation, are studied. Based on the parametric study of band of frequency gap two kind of periodic foundation are designed. In particular, the layered periodic foundation composed of several concrete and rubber layers, and the periodic foundation composed of concrete layers with interposed rubber blocks, are considered. To test the effectiveness of the isolation ability of these periodic foundations, the dynamic responses of a concrete frame and of a steel frame with the periodic foundations are evaluated and compared with the response of the structures without the metafoundation. First, the analyses are conducted in the frequency domain in order to be able to define the number of unit cell needed to reach the band gaps, previously defined for the infinite periodic foundation. Then, the analyses with sinusoidal waves, in the time domain, show that the waves cannot propagate in the periodic foundation without being attenuated when the frequencies of the seismic wave fall into the band gap of the periodic foundation. Finally, to illustrate the efficiency of these seismic isolation foundations, different ground motion are applied to the structures. The results show that the seismic responses of the structure with the periodic foundation are greatly attenuated as compared with those of the structure without periodic foundation.
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Koprivnjak, Jean-François. "Natural Organic Matter: Isolation and Bioavailability." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14564.
Повний текст джерелаАнотація:
Electrodialysis (ED) experiments were conducted on reverse osmosis (RO)-concentrated solutions of NOM from six rivers. The ED processes successfully recovered 88 11% of TOC, and removed 83% 19% of SO42- and 67% 18% of H4SiO4. More importantly, the molar ratios of SO42- /TOC and H4SiO4 /TOC were reduced to a mean value of 0.0046 and 0.032, respectively, surpassing the goal for removal of SO42- (0.008) and almost achieving the goal for removal of H4SiO4 (0.021). The ED process can lower the SO42- /TOC ratio in samples whose initial SO42- /TOC ratios are already far below the limit of 0.008 used in this study. The coupled RO/ED process that has been described here offers a fast, simple, chemically mild (relative to other methods), and reproducible method of isolation of large quantities of relatively unfractionated, low-ash NOM from freshwaters.
RO/ED was also successfully used for isolating and concentrating marine dissolved organic matter (DOM). The effort successfully recovered a median of 72% of the TOC from 200 L samples within six to nine hours of processing through a combination of ED and RO, greatly exceeding the current norm of 30%. The relatively high recovery of DOM implies that classes of DOM previously missing are included in these samples and should yield new insight into the chemistry of marine DOM.
Freshwater samples processed by electrodialysis were analyzed for elemental composition and by capillary zone electrophoresis (CZE), 1H and 13C nuclear magnetic resonance spectroscopy (NMR), and electro-spray ionization mass spectrometry (ESI-MS). Bulk elemental composition, 1H- and 13C-NMR, and ESI-MS data provide evidence linking bioavailabilty to the bulk chemistry of NOM: the H/C and N/C molar ratios are positively and strongly correlated with bioavailability, as hypothesized.
Using an independent dataset (STORET) of water quality parameters, calculated BOD/TOC ratios were found to be moderately correlated with measured bioavailabilities and can be used as a surrogate for bioavailability of geochemically diverse riverine DOM.
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Cinarel, Dilara. "Vibration Isolation Of Inertial Measurement Unit." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614069/index.pdf.
Повний текст джерелаАнотація:
Sensitive devices are affected by extreme vibration excitations during operation so require isolation from high levels of vibration excitations. When these excitation characteristics of the devices are well known, the vibration isolation can be achieved accurately. However, it is possible to have expected profile information of the excitations with respect to frequency. Therefore, it is practical and useful to implement this information in the design process for vibration isolation.
In this thesis, passive vibration isolation technique is examined and a computer code is developed which would assist the isolator selection process. Several sample cases in six degree of freedom are designed for a sample excitation and for sample assumptions defined for an inertial measurement unit. Different optimization methods for design optimizations are initially compared and then different designs are arranged according to the optimization results using isolators from catalogues for these sample cases.
In the next step, the probable designs are compared according to their isolator characteristics. Finally, one of these designs are selected for each case, taking into account both the probable location deviations and property deviations of isolators.
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Held, Lucas. "Implantation isolation in AlGaAs/GaAs structures." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32366.
Повний текст джерелаАнотація:
In this work the effect of implantation isolation in vertical cavity surface emitting laser (VCSEL) samples have been investigated cross sectional measurements using scanning spreading resistance microscopy (SSRM). The samples consist of two AlGaAs/GaAs Distributed Bragg Reflectors (DBR) structures with a GaAs quantum well region sandwiched in between them. The samples were implanted with 330 and 660 keV helium ions using doses from 7*1013 cm-2 to 1*1016 cm-2. Due to variations and uncertainties in the SSRM output quantitative values of resistivity in the highly resistive regions created by ion implantations were not attained. Relative differences, however, were notable for the different doses. It was found that the resistive regions were not located as deep inside the samples for the 660 keV implantations as for the 330 keV. This does not agree with the simulations performed. A correlation between implantation dose and the depth of the resistive region created was also found - higher doses caused resistive regions deeper inside the samples. Furthermore, as the implantation dose is increased the resistive region is confined to only about one AlGaAs/GaAs period of width at the same depth as the wide resistive region for lower doses, i.e. the structure is somehow regaining its conductive properties in the shallow areas only leaving a thin stripe of the resistive region at the deepest end for higher implantation doses. Samples implanted with low He doses were heated in a vacuum furnace at 300, 350 and 380 ˚C. The heated samples showed a tendency to regain the conductivity in the resistive region, similar to the samples implanted with high doses. This suggests that there may be some kind of annealing effect for higher doses, possibly due to the increased flux for higher doses.
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Ahmed, Abu Hanieh. "Multi degrees of freedom vibration isolation." Doctoral thesis, Universite Libre de Bruxelles, 2001. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211553.
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Koprivnjak, Jean-Franȯis. "Natural organic matter isolation and bioavailability /." Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-04082007-154052/.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2007.<br>Perdue, E. Michael, Committee Chair ; Ingall, Ellery, Committee Member ; Stack, Andrew, Committee Member ; Nenes, Athanasios, Committee Member ; Pfromm, Peter, Committee Member.
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Biteus, Jonas. "Fault Isolation in Distributed Embedded Systems." Doctoral thesis, Linköping : Vehicular Systems, Department of Electrical Engineering, Linköpings universitet, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8774.
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Drexel, Michael V. "Modal parameter identification using mode isolation." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17239.
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Houalla, Tarek. "Isolation of microglia from goldfish brain." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31238.
Повний текст джерелаАнотація:
This study aims at providing a new technique for the isolation and culture of goldfish microglial cells. So far no protocol has been designed for the growth of these cells in vitro, despite the growing interest in the remarkable capacity of goldfish central nervous system (CNS) for regenerating severed axons. This newly developed technique has little or no similarity to those used in the isolation of mammalian microglia, and is distinguished by its simple setup and its fast yield for microglial cells. In addition, a virtually pure population of microglia was generated when plated on untreated plastic dishes, eliminating further need for purification. This technique may thus provide a starting point for future characterization of the microglial cells in vitro, which may eventually help toward building a better understanding of the function and biology of these cells. A preliminary morphological characterization of the cells has also been conducted, in addition to groundwork experiments on the phagocytic activity of these cells in vitro, using myelin to stimulate phagocytosis. These assays were oriented toward providing a comparison to the mammalian cultures of microglia, and so far, displayed several similarities in morphologies and phagocytosis.
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Shan, Yulong. "Bioactive carbohydrates : isolation, synthesis and conjugation." Thesis, Bangor University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556079.
Повний текст джерелаАнотація:
In this thesis four projects related to bioactive carbohydrates are described. The first project is about the extraction of iminosugars from Hyacinthoides non-scripta. This is the first time that extraction from English bluebell seeds has been described. Efficient extraction and isolation methods are reported. Another project discusses the development of a total synthetic carbohydrate conjugate vaccine candidate against Streptococcus pneumoniae type 14 using Gold nanoparticles as carrier. The synthetic pathway of the introduction of a linker for conjugation, and the deprotection of the tetrasaccharide corresponding to the repeating unit of the Streptococcus pneumoniae type 14 capsular polysaccharide is described. The biological results of the developed vaccine candidate are briefly discussed. In the third project, attempts to synthesise regioselectively sulfated disaccharides to be used in binding studies with FedF adhesin of E. coli are described. In this section, an improved high-yielding method based on the Heyns rearrangement for the synthesis of N-acetyl lactosamine (LacNAc) is also reported. In the fourth part, conjugation of the Lewis b hexasaccharide to be used for studies of Lewis b blood group antigen binding adhesin is reported.
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Charng, Peng-Hsiang. "Base isolation for multistorey building structures." Thesis, University of Canterbury. Civil Engineering, 1998. http://hdl.handle.net/10092/5851.
Повний текст джерелаАнотація:
Earthquakes are one of nature’s greatest hazards; throughout historic time they have caused significant loss of life and severe damage to property, especially to man-made structures. On the other hand, earthquakes provide architects and engineers with a number of important design criteria foreign to the normal design process. From well established procedures reviewed by many researchers, seismic isolation may be used to provide an effective solution for a wide range of seismic design problems.
The application of the base isolation techniques to protect structures against damage from earthquake attacks has been considered as one of the most effective approaches and has gained increasing acceptance during the last two decades. This is because base isolation limits the effects of the earthquake attack, a flexible base largely decoupling the structure from the ground motion, and the structural response accelerations are usually less than the ground acceleration.
In this research, a series of dynamic analyses are carried out to investigate in detail the seismic responses for stiff and flexible 12-storey multi storey buildings to the various isolation systems and to consider the effects of foundation compliance on their responses when subjected to different earthquakes. At the same time, an investigation of the seismic response of the recently suggested segmental buildings is carried out. The segmental building concept can be considered as an extension of the conventional base isolation technique with additional flexibility distributed in the superstructure. In addition to the conventional isolation system placed at the base, the superstructure of segmental buildings is further divided into several segments which are interconnected by extra isolation systems located in the upper storeys.
In general, the increase of additional viscous damping in the structure may reduce displacement and acceleration responses of the structure. This study also seeks to evaluate the effects of additional damping on the seismic response when compared with structures without additional damping for the different ground motions. In addition, analysis and design considerations for base isolated and segmental structures are suggested to enable the designer to get a better understanding at the preliminary design stage.