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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Sensor network and soft sensor design for stable nonlinear dynamic systems

Singh, Abhay Kumar 30 October 2006 (has links)
In chemical processes, online measurements of all the process variables and parameters required for process control, monitoring and optimization are seldom available. The use of soft sensors or observers is, therefore, highly significant as they can estimate unmeasured state variables from available process measurements. However, for reliable estimation by a soft sensor, the process measurements have to be placed at locations that allow reconstruction of process variables by the soft sensors. This dissertation presents a new technique for computing an optimal measurement structure for state and parameter estimation of stable nonlinear systems. The methodology can compute locations for individual sensors as well as networks of sensors where a trade-off between process information, sensor cost, and information redundancy is taken into account. The novel features of the approach are (1) that the nonlinear behavior that a process can exhibit over its operating region can be taken into account, (2) that the technique is applicable for systems described by lumped or by distributed parameter models, (3) that the technique reduces to already established methods, if the system is linear and only some of the objectives are examined, (4) that the results obtained from the procedure can be easily interpreted, and (5) that the resulting optimization problem can be decomposed, resulting in a significant reduction of the computational effort required for its solution. The other issue addressed in this dissertation is designing soft sensors for a given measurement structure. In case of high-dimensional systems, the application of conventional soft sensor or observer designs may not always be practical due to the high computational requirements or the resulting observers being too sensitive to measurement noise. To address these issues, this dissertation presents reduced-order observer design techniques for state estimation of high-dimensional chemical processes. The motivation behind these approaches is that subspaces, which are close to being unobservable, cannot be correctly reconstructed in a realistic setting due to measurement noise and inaccuracies in the model. The presented approaches make use of this observation and reconstruct the parts of the system where accurate state estimation is possible.
142

Study on the Secondary Metablities of the Formosan Soft Coral Sinularia facile

chen, Bo-wei 24 August 2007 (has links)
Our chemical investigation on the soft coral Sinularia facile which was collected off the coast of Kengting, Taiwan, has led to the isolation of ten metabolites 1¡Ð10, including four cembranoids and six polyhydroxylated steroids. Cembranoids isolated are two new natural compounds, (3E,7E,11E,15E)-cembra-3,7,11,15-tetraen-1-ol (1) and (1R*,12R*,3E,7E,10E,15E)-cembra-3,7,10,15-tetraen-12-ol (2), and two known compounds diepoxycembrene A (3) and isocembrol A (4). Moreover, five new polyhydroxylated steroids, cholest-5-ene-1£\,3£]-diol- 11£\-monoacetate (5), cholesta-5,24-diene-1£\,3£] -diol-11£\-monoacetate (6), cholesta-5,24-diene-1£\,3£]-11£\-triol (7), 24- methylenecholesta-5-ene-1£\, 3£]-diol-11£\,18-diacetate (8) and 24(S)- methylcholest-5-ene-1£\,3£]-diol- 11£\-monoacetate (9), and one known compound, 24-methylenecholest-5- ene-1£\,3£],11£\-triol (10). The chemical structures of these compounds (1¡Ð10) were elucidated by spectroscopic evidences (IR, MS, 1D NMR, and 2D NMR) and by comparison of the spectral data of these compounds in the literature. Cytotoxicity of these compounds toward various cancer cell lines has also been determined.
143

Human Emotion Recognition from Body Language of the Head using Soft Computing Techniques

Zhao, Yisu 31 October 2012 (has links)
When people interact with each other, they not only listen to what the other says, they react to facial expressions, gaze direction, and head movement. Human-computer interaction would be enhanced in a friendly and non-intrusive way if computers could understand and respond to users’ body language in the same way. This thesis aims to investigate new methods for human computer interaction by combining information from the body language of the head to recognize the emotional and cognitive states. We concentrated on the integration of facial expression, eye gaze and head movement using soft computing techniques. The whole procedure is done in two-stage. The first stage focuses on the extraction of explicit information from the modalities of facial expression, head movement, and eye gaze. In the second stage, all these information are fused by soft computing techniques to infer the implicit emotional states. In this thesis, the frequency of head movement (high frequency movement or low frequency movement) is taken into consideration as well as head nods and head shakes. A very high frequency head movement may show much more arousal and active property than the low frequency head movement which differs on the emotion dimensional space. The head movement frequency is acquired by analyzing the tracking results of the coordinates from the detected nostril points. Eye gaze also plays an important role in emotion detection. An eye gaze detector was proposed to analyze whether the subject's gaze direction was direct or averted. We proposed a geometrical relationship of human organs between nostrils and two pupils to achieve this task. Four parameters are defined according to the changes in angles and the changes in the proportion of length of the four feature points to distinguish avert gaze from direct gaze. The sum of these parameters is considered as an evaluation parameter that can be analyzed to quantify gaze level. The multimodal fusion is done by hybridizing the decision level fusion and the soft computing techniques for classification. This could avoid the disadvantages of the decision level fusion technique, while retaining its advantages of adaptation and flexibility. We introduced fuzzification strategies which can successfully quantify the extracted parameters of each modality into a fuzzified value between 0 and 1. These fuzzified values are the inputs for the fuzzy inference systems which map the fuzzy values into emotional states.
144

Non-felkin diastereoselectivity in aldol couplings of thiopyran-based polypropionate synthons

Theaker, Nikki E. 13 January 2010
Polypropionates represent a large family of natural products and several strategies have been developed for their synthesis. The aldol reaction is one of the most important tools for the construction of polypropionate natural products. The Ward group has developed an approach to polypropionate natural products based on sequential aldol reactions of thiopyran building blocks. The Thiopyran Route to Polypropionates (TR2P) involves the stepwise aldol reactions of 15 and 16 to rapidly access stereochemically complex tetrapropionate and hexapropionate synthons in a few steps. The current work describes the effort to prepare enantioenriched 17-AA and/or 17-SA through chiral transition metal based Lewis acids (176) and chiral organocatalysts (48, 179) with chelating Lewis acids. The preparation of non-Felkin tetrapropionate and hexapropionate synthons through the use of a weak base in conjunction with a Lewis acid was developed.
145

Planificación de Diferentes Clases de Aplicaciones en Entornos No Dedicados Considerando Procesadores Multicore

García Gutiérrez, José Ramón 19 July 2010 (has links)
A día de hoy es prácticamente imposible encontrar una gran institución que no disponga de un parque de ordenadores considerable, debido al alto nivel de informatización de la sociedad actual. El enorme potencial que representan estos miles de ordenadores atrae poderosamente la atención en los ámbitos científicos e industriales, generando opciones viables para su aprovechamiento. Las universidades, instituciones que históricamente se han mantenido a la vanguardia en la investigación e innovación científica, representan un caso especialmente bien posicionado a la hora de generar tanto los recursos informáticos como la necesidad de su uso.El poder de cómputo existente en los laboratorios y aulas de estudio universitarias, agrupaciones naturales de recursos informáticos, crea grandes oportunidades para la computación paralela, animándonos a buscar opciones viables para su aprovechamiento. Como resultado de este interés, nuestro grupo ha creado un entorno de planificación, enfocado hacia los clusters no dedicados. La constante y rápida evolución de los componentes, tanto a nivel de la arquitectura de la CPU como del sistema operativo, así como de las aplicaciones ejecutadas, hace que tengamos que adaptar nuestras propuestas. Nuestra propuesta consiste en crear una Máquina Virtual con doble funcionalidad, ejecutar la carga local de usuario y aprovechar los períodos de inactividad de nodos a efectos de poder usarlos para ejecutar carga paralela. Tanto el tipo de las aplicaciones como las características del hardware del escenario objetivo, y en el momento actual ambas han evolucionado. Nuevos tipos de aplicaciones paralelas con requerimientos periódicos de CPU son cada día más comunes en el mundo científico e industrial. Este tipo de aplicaciones pueden requerir un tiempo de retorno (turnaround) específico o una Calidad de Servicio (Quality of Service, QoS) determinada. Para nuestro caso particular, reviste especial importancia el conocimiento que poseemos de los usuarios locales, debido a que nuestro entorno está diseñado para trabajar en clusters no dedicados. Un usuario local puede estar visualizando un vídeo almacenado en su ordenador, lo cual implica necesidades de CPU periódicas y un mayor uso de memoria. La aparición de nuevos tipos de aplicaciones, como vídeo bajo demanda ó realidad virtual, que se caracterizan por la necesidad de cumplir sus deadlines, presentando requerimientos periódicos de recursos. Este tipo de aplicaciones, donde la pérdida de deadlines no se considera un fallo severo, han sido denominadas en la literatura aplicaciones soft-real time (SRT) periódicas.Esta interesante evolución de las necesidades de los usuarios no es el único digno de atención. El crecimiento en la capacidad de cómputo de los procesadores en los últimos años se ha visto frenado a causa de las barreras físicas del espacio y la velocidad de las señales, obligando a los fabricantes de procesadores a explorar otras vías de crecimiento. Desde hace ya algún tiempo el paralelismo de las aplicaciones se ha convertido en una de las grandes apuestas. Hoy en día los procesadores de dos núcleos son la mínima configuración que encontraremos en un ordenador, y se prevé que el número de núcleos continuará creciendo en los próximos años.Los clusters no dedicados ofrecen un gran potencial de un uso, debido a que los recursos materiales ya están disponibles y el cálculo paralelo se realiza simultáneamente con el del usuario local. Imaginando el escenario actual en los clusters no dedicados, encontramos nuevas aplicaciones de escritorio y paralelas, así como plataformas hardware más potentes y complejas. En esta situación investigar el problema y realizar propuestas relacionadas con la planificación de los diferentes tipos de aplicaciones en clusters no dedicados, considerando las plataformas multicore, supone un nuevo reto a asumir por los investigadores y conforma el núcleo de este trabajo. / Today it is virtually impossible to find an institution that does not have a considerable amount of computers, due to the high level of computerization of society. The enormous potential of these large number of computers attract a lot of attention in science and industry, generating viable options for their use. The universities, institutions that historically have remained at the forefront of research and scientific innovation, represent a case particularly well positioned in generating both, computing resources and the need to use. The computational power present in laboratories and university study rooms, natural groupings of information resources, creating great opportunities for parallel computing, encouraging us to seek viable options for their use. As a result of this interest, our group has created a parallel scheduling environment, focused on non-dedicated clusters. The constant and fast evolution of the components, both at the architecture of the CPU and the operating system and applications executed, forces us to adapt our proposals. Our proposal is to create a Virtual Machine with dual functionality, run the local load user and take advantage of downtime for the purposes of nodes it can be used to run parallel load. At present both, applications and hardware specifications of the target scenario, have evolved. New types of parallel applications with periodic CPU requirements are becoming more common in science and industry. Such applications may require a return time (turnaround) or a specific QoS (Quality of Service). Since our framework is designed to work in non-dedicated clusters, having knowledge of the local users behavior is of particular importance. A local user may be viewing a video stored on your computer, which involves periodic CPU requirements and increased use of memory. The emerging new types of applications, such as video on demand or virtual reality are a fact. This new types of applications are characterized by the need to meet their deadlines, presenting periodic resource requirements. This type of application, where the loss of deadlines is not considered a severe failure, has been named in the literature uses soft-real time (SRT) at regular intervals. This exciting evolution of user needs is not the only one worthy of attention. The growth in computing power of processors in recent years has been hampered because of the physical barriers of space and speed of the signals, forcing chip makers to explore other avenues of growth. For some time the parallelism of the applications has become one of the biggest bets. Today's dual-core processors are the minimum configuration of any computer, and it is expected that the number of nuclei continue to grow in the coming years. The non-dedicated clusters offer great potential for use, because the computational resources are already available, and parallel computing is performed simultaneously with the local user. Figuring out the current scenario in the non-dedicated clusters, we find new desktop applications, parallel and more powerful and complex hardware platforms. In this situation, research lines related to the planning of the different types of applications in non dedicated clusters, considering multi-core platforms, is a new challenge to be assumed by researchers and constitute the core of this work.
146

Genetiska ultraljudsmarkörer : Hur bör information till blivande föräldrar i samband med rutinultraljudet hanteras?

Vallin, Martina January 2012 (has links)
Objective: The purpose of the study is to explore and illustrate how ultrasound midwives and medical specialist in obstetrics and gynecology believe the information given to parents about the genetic soft markers should be handled. Design: A quantitative questionnaire study with cross-sectional design. Participants: 44 ultrasound midwives and 37 medical specialists in obstetrics and gynecology. Findings: Most of the participants would like to inform before the ultrasound starts that they will be looking for genetic softmarkers during the ultrasound. Likewise the majority wanted to inform the parents about possible increases in the risk for chromosomal abnormalities based on findings on the routine ultrasound. There was a difference in frequency between those who responded that they would like to inform before the ultrasound that they will be looking for genetic softmarkers and those who responded that they believe the future parents wants information before the examination. Key conclusions: It could help health care professionals in their role as information providers if there were common recommendations for the information to be given to future parents about genetic softmarkers in connection with the routine ultrasound. / Syfte: Syftet med studien är att undersöka och belysa hur ultraljudbarnmorskor och specialistläkare inom obstetrik och gynekologi anser att informationen som ges till blivande föräldrar kring genetiska ultraljudsmarkörer bör hanteras. Design: En kvantitativ enkätstudie med tvärsnittsdesign. Deltagare: 44 ultraljudsbarnmorskor och 37 specialistläkare inom obstetrik och gynekologi. Resultat: Merparten av deltagarna vill informera innan ultraljudundersökningen börjar om att de kommer att titta efter genetiska ultraljudmarkörer under rutinultraljudet. Likaså ville majoriteten informera de blivande föräldrarna om eventuella riskökningar för kromosomavvikelser utifrån upptäckter på rutinultraljudet. Det fanns en skillnad i frekvens mellan de som svarat att de ville informera innan ultraljudsundersökningen om att de kommer att titta efter genetiska ultraljudsmarkörer och de som svarat att de tror att de blivande föräldrarna vill ha denna information innan undersökningen. Slutsats: Det skulle kunna hjälpa hälso-och sjukvårdspersonal i sin uppgift som informationsgivare om det fanns genomsamma rekommendationer för vilken information som skall ges till blivande föräldrar kring genetiska ultraljudsmarkörer i samband med rutinultraljudet. På det sättet skulle vi erbjuda en mer jämställd information och vård till hela befolkningen oberoende av var de bor.
147

Soft Error Resistant Design of the AES Cipher Using SRAM-based FPGA

Ghaznavi, Solmaz January 2011 (has links)
This thesis presents a new architecture for the reliable implementation of the symmetric-key algorithm Advanced Encryption Standard (AES) in Field Programmable Gate Arrays (FPGAs). Since FPGAs are prone to soft errors caused by radiation, and AES is highly sensitive to errors, reliable architectures are of significant concern. Energetic particles hitting a device can flip bits in FPGA SRAM cells controlling all aspects of the implementation. Unlike previous research, heterogeneous error detection techniques based on properties of the circuit and functionality are used to provide adequate reliability at the lowest possible cost. The use of dual ported block memory for SubBytes, duplication for the control circuitry, and a new enhanced parity technique for MixColumns is proposed. Previous parity techniques cover single errors in datapath registers, however, soft errors can occur in the control circuitry as well as in SRAM cells forming the combinational logic and routing. In this research, propagation of single errors is investigated in the routed netlist. Weaknesses of the previous parity techniques are identified. Architectural redesign at the register-transfer level is introduced to resolve undetected single errors in both the routing and the combinational logic. Reliability of the AES implementation is not only a critical issue in large scale FPGA-based systems but also at both higher altitudes and in space applications where there are a larger number of energetic particles. Thus, this research is important for providing efficient soft error resistant design in many current and future secure applications.
148

DNA functionalized soft materials: preparation, biophysical properties and analytical applications.

Dave, Neeshma 12 November 2012 (has links)
Bio-nanotechnology is the use of biomolecules to control both the structure and property of nanomaterials. No biomolecule has been employed more often than DNA as exemplified in the numerous demonstrations of DNA-directed assembly of nanomaterials. DNA has been used to covalently functionalize and assemble soft nanoparticles (e.g. liposomes) and hard nanoparticles (e.g. gold and silica nanoparticles) into a variety of hierarchical nanostructures. The majority of previous work however has focused on the latter, i.e., the assembly of “hard” nanoparticles such as gold nanoparticles (AuNPs) as oppose to the assembly of soft materials. The primary focus of this thesis is to add to the growing field of DNA-directed assembly of soft materials owing to the promise of such materials in a variety of analytical and biomedical applications. The first class of soft materials considered are liposomes which interestingly can be deformed by relatively weak intermolecular forces. In addition, DNA anchored to its surface can readily diffuse laterally within the lipid bilayer while DNA attached to inorganic nanoparticles remain fixed in position. We systematically consider the effect of varying the liposome structure, size, charge, and fluidity on liposome assemblies, in chapter 2. In addition, the interesting properties of liposomes are highlighted by a side-by-side comparison to DNA-functionalized gold nanoparticles, offering fundamental insights into DNA-directed assembly. Furthermore, hybrid DNA-directed assemblies composed of both AuNPs and liposomes are described in Chapter 3. In particular, the photothermal effects of such DNA-coupled liposome and AuNP assemblies were modulated by controlling the distance between liposome and AuNP allowing such systems to have potential application in drug-delivery. In chapter 4, the utility of liposomes is demonstrated as we exploit the fluidity of its diffuse bilayer with split aptamer functionalization for the rapid and selective detection of metabolites. The second class of soft material of interest in this thesis are hydrogels, which are cross-linked hydrophilic polymers. Because hydrogels are swollen in water, they can be used to immobilize biomolecules such as DNA for a myriad of applications. In chapter 5, the preparation and characterization of DNA-functionalized polyacrylamide hydrogels are presented. The use of such a DNA-modified hydrogel for the simultaneous detection and removal of mercury from water is subsequently demonstrated.
149

Non-felkin diastereoselectivity in aldol couplings of thiopyran-based polypropionate synthons

Theaker, Nikki E. 13 January 2010 (has links)
Polypropionates represent a large family of natural products and several strategies have been developed for their synthesis. The aldol reaction is one of the most important tools for the construction of polypropionate natural products. The Ward group has developed an approach to polypropionate natural products based on sequential aldol reactions of thiopyran building blocks. The Thiopyran Route to Polypropionates (TR2P) involves the stepwise aldol reactions of 15 and 16 to rapidly access stereochemically complex tetrapropionate and hexapropionate synthons in a few steps. The current work describes the effort to prepare enantioenriched 17-AA and/or 17-SA through chiral transition metal based Lewis acids (176) and chiral organocatalysts (48, 179) with chelating Lewis acids. The preparation of non-Felkin tetrapropionate and hexapropionate synthons through the use of a weak base in conjunction with a Lewis acid was developed.
150

Development and Construct Validation of a Measure of Soft Skills Performance

Kantrowitz, Tracy Michelle 10 April 2005 (has links)
Despite the growing interest in studying the dimensions and prediction of task and contextual performance, little empirical attention has been given to studying the nature of soft skills performance. Soft skills (i.e., intra- and inter-personal work skills that facilitate the application of technical skills and knowledge), such as interpersonal skills (e.g., developing rapport) and communication skills (e.g., adjusting your message to the target audience) are highly sought by organizations (Zedeck and Goldstein, 2000). However, little is known about the underlying dimensions of soft skills performance, or about the individual differences variables that predict performance in this domain. In the current set of studies I examined the dimensionality of soft skills performance, developed measures to assess soft skills performance from self and supervisor perspectives, and validated the measures of performance in a nomological network of non-ability individual differences and existing performance measures. Study 1 involved asking subject matter experts to provide a master list and critical incidents of soft skills. Data from Study 1 served as the stimuli in Study 2 for sorting and reduction of skills into dimensions of soft skills performance. A construct and criterion validation approach was taken in Study 3 to measure soft skills performance in relation to individual differences variables in a nomological network. Results showed that the taxonomy of soft skills performance was composed of seven clusters, but that the measure of soft skills performance was unidimensional. Personality and motivational variables significantly predicted soft skills performance through their influence on proximal motivational processes.

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