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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.
41

Strong Angels of Comfort: Middle Class Managing Daughters in Victorian Literature

Dotson, Emily A 01 January 2014 (has links)
This dissertation joins a vibrant conversation in the social sciences about the challenging nature of care labor as well as feminist discussions about the role of the daughter in Victorian culture. It explores the literary presence of the middle class managing daughter in the Victorian home. Collectively, the novels in this study articulate social anxieties about the unclear and unstable role of daughters in the family, the physically and emotionally challenging work they, and all women, do, and the struggle for daughters to find a place in a family hierarchy, which is often structured not by effort or affection, but by proscribed traditional roles, which do not easily adapt to managing daughters, even if they are the ones holding the family together. The managing daughter is a problem not accounted for in any conventional domestic structure or ideology so there is no role, no clear set of responsibilities and no boundaries that could, and arguably should, define her obligations, offer her opportunities for empowerment, or set necessary limits on the broad cultural mandate she has to comfort and care others. The extremes she is often pushed to reveals the stresses and hidden conflicts for authority and autonomy inherent in domestic labor without the iconic angel in the house rhetoric that so often masks the difficulties of domestic life for women. She gains no authority or stability no matter how loving or even how necessary she is to a family because there simply is no position in the parental family structure for her. The managing daughter thus reveals a deep crack in the structure of the traditional Victorian family by showing that it often cannot accommodate, protect, or validate a loving non-traditional family member because it values traditional hierarchies over emotion or effort. Yet, in doing so, it also suggests that if it is position not passion that matters, then as long as a woman assumes the right position in the family then deep emotional connections to others are not necessary for her to care competently for others.
42

A hardware algorithm for modular multiplication/division

高木, 直史, Takagi, Naofumi 01 1900 (has links)
No description available.
43

Spatial coherence measurement of undulator radiation using uniformly redundant arrays

Lin, John Jia An January 2003 (has links) (PDF)
Synchrotron light source are accelerating research and development and fueling innovation in a wide range of research disciplines and industries worldwide. The third-generation synchrotron radiation facilities such as Advanced Photon Source (APS), produce ultra-brilliant x-rays using insertion devices consisting mainly of undulators, which provide exciting opportunities for advanced research into materials, earth science, life science, and medicine. Using high brightness x-ray radiation with high spatial coherence, unique coherence-based experiments are now becoming possible: coherence imaging techniques such as phase contrast imaging, holography, and tomography, are under intensive development, opening up a range of new areas of investigation. At the same time some useful optical elements used in the synchrotron radiation system have been created rapidly. Crucial to the development of all these fields is some knowledge of the spatial coherence of the light produced by these sources. In other words, the characterization of spatial coherence is a high priority. / The aim of this project is to develop a theoretical and experimental program to allow the measurement of the spatial coherence of synchrotron radiation. A technique to measure the spatial coherence of x-rays from undulators is presented. The essence of the coherence measurement technique is based on the interpretation of a complex diffraction pattern. We measure the spatial coherence function of a 7.9 keV x-ray beam from an undulator at a third-generation synchrotron (APS) using a sophisticated diffracting aperture known as a Uniformly Redundant Array (URA). The URA was also used to measure the spatial coherence function for soft x-rays at the APS. When a traditional Young’s double-slit experiment is used to test the degree of coherence, the separations of the two-slit have to be changed repeatedly to full map the spatial coherence function. The URA is a complex aperture consisting of many slits, (or, for a two-dimensional array, pinholes), organized such that all possible slit separations occur, and do so with exactly the same frequency. One might regard the URA as able to simultaneously perform many Young’s experiments a precisely equal number of times across the full range of slit separations permitted by the overall size of the URA. Therefore one experiment using a one-dimensional (1D) URA can perform the equivalent of multiple double-slit experiments. The diffraction theory developed in this thesis a convenient theoretical basis for interpreting this diffraction pattern.
44

Κατασκευή και έλεγχος λαπαροσκοπικού χειρουργικού ρομποτικού βραχίονα με πλεονάζοντες βαθμούς ελευθερίας

Μαυρομμάτη, Αναστασία, Τζωρακολευθεράκης, Εμμανουήλ 31 May 2012 (has links)
Ο στόχος της εργασίας αυτής είναι η κατασκευή και ο έλεγχος ενός λαπαροσκοπικού εργαλείου με πλεονάζοντες βαθμούς ελευθερίας (ΒΕ). Ο βραχίονας αποτελείται από συνδεδεμένα τμήματα ή «σπονδύλους» που ενεργοποιούνται από καλώδια Ni-Ti, γνωστά και ως Shape Memory Alloys, που λειτουργούν ως δυαδικοί ενεργοποιητές με 2 καταστάσεις. Έτσι, εξασφαλίζεται η επαναληψιμότητα στις κινήσεις του βραχίονα και δεν απαιτούνται αισθητήρες για τη θέση των αρθρώσεων. Κάθε σπόνδυλος αποτελείται από 3 ενεργούς πρισματικούς ενεργοποιητές (SMA) τοποθετημένους έτσι ώστε να σχηματίζουν ένα τρίποδο, το οποίο παρέχει 3 ΒΕ σε κάθε άρθρωση (δύο περιστροφικούς και ένα μεταφορικό). Η ανεξάρτητη ενεργοποίηση κάθε άρθρωσης γίνεται από μικροελεγκτές που επικοινωνούν με το πρωτόκολλο I2C και είναι τοποθετημένοι στο εσωτερικό κάθε συνδέσμου. Θα παρουσιαστούν διάφορα ζητήματα σχεδιασμού, η κινηματική και η προσομοίωση του εργαλείου, καθώς και ένα αρχικό πείραμα. / The subject of this work is the development of a prototype hyper-redundant laparoscopic tool. The manipulator consists of cascaded modules which are powered by Shape Memory Alloy wires (NiTi), acting as binary actuators with two stable states. As a result, the repeatability of the manipulator’s movement is ensured, alleviating the need for sensing of the manipulator’s joint-positions. Each module is composed of three active prismatic actuators in a tripod configuration providing a 3-DOF (two rotational and one translational) maneuverability for each joint. I2C-networked microcontrollers activate the individual tendon in each joint. Certain design aspects as well as the kinematics of the binary manipulator are presented followed by simulation and experimental studies on the laparoscopic tool prototype.
45

UnSync: A Soft Error Resilient Redundant CMP Architecture

January 2011 (has links)
abstract: Reducing device dimensions, increasing transistor densities, and smaller timing windows, expose the vulnerability of processors to soft errors induced by charge carrying particles. Since these factors are inevitable in the advancement of processor technology, the industry has been forced to improve reliability on general purpose Chip Multiprocessors (CMPs). With the availability of increased hardware resources, redundancy based techniques are the most promising methods to eradicate soft error failures in CMP systems. This work proposes a novel customizable and redundant CMP architecture (UnSync) that utilizes hardware based detection mechanisms (most of which are readily available in the processor), to reduce overheads during error free executions. In the presence of errors (which are infrequent), the always forward execution enabled recovery mechanism provides for resilience in the system. The inherent nature of UnSync architecture framework supports customization of the redundancy, and thereby provides means to achieve possible performance-reliability trade-offs in many-core systems. This work designs a detailed RTL model of UnSync architecture and performs hardware synthesis to compare the hardware (power/area) overheads incurred. It then compares the same with those of the Reunion technique, a state-of-the-art redundant multi-core architecture. This work also performs cycle-accurate simulations over a wide range of SPEC2000, and MiBench benchmarks to evaluate the performance efficiency achieved over that of the Reunion architecture. Experimental results show that, UnSync architecture reduces power consumption by 34.5% and improves performance by up to 20% with 13.3% less area overhead, when compared to Reunion architecture for the same level of reliability achieved. / Dissertation/Thesis / M.S. Computer Science 2011
46

Energy-efficient DSP System Design based on the Redundant Binary Number System

January 2011 (has links)
abstract: Redundant Binary (RBR) number representations have been extensively used in the past for high-throughput Digital Signal Processing (DSP) systems. Data-path components based on this number system have smaller critical path delay but larger area compared to conventional two's complement systems. This work explores the use of RBR number representation for implementing high-throughput DSP systems that are also energy-efficient. Data-path components such as adders and multipliers are evaluated with respect to critical path delay, energy and Energy-Delay Product (EDP). A new design for a RBR adder with very good EDP performance has been proposed. The corresponding RBR parallel adder has a much lower critical path delay and EDP compared to two's complement carry select and carry look-ahead adder implementations. Next, several RBR multiplier architectures are investigated and their performance compared to two's complement systems. These include two new multiplier architectures: a purely RBR multiplier where both the operands are in RBR form, and a hybrid multiplier where the multiplicand is in RBR form and the other operand is represented in conventional two's complement form. Both the RBR and hybrid designs are demonstrated to have better EDP performance compared to conventional two's complement multipliers. The hybrid multiplier is also shown to have a superior EDP performance compared to the RBR multiplier, with much lower implementation area. Analysis on the effect of bit-precision is also performed, and it is shown that the performance gain of RBR systems improves for higher bit precision. Next, in order to demonstrate the efficacy of the RBR representation at the system-level, the performance of RBR and hybrid implementations of some common DSP kernels such as Discrete Cosine Transform, edge detection using Sobel operator, complex multiplication, Lifting-based Discrete Wavelet Transform (9, 7) filter, and FIR filter, is compared with two's complement systems. It is shown that for relatively large computation modules, the RBR to two's complement conversion overhead gets amortized. In case of systems with high complexity, for iso-throughput, both the hybrid and RBR implementations are demonstrated to be superior with lower average energy consumption. For low complexity systems, the conversion overhead is significant, and overpowers the EDP performance gain obtained from the RBR computation operation. / Dissertation/Thesis / M.S. Electrical Engineering 2011
47

Uma contribuição para a análise da confiabilidade de sistemas redundantes com inspeção periódica

Mendes, Angélica Alebrant January 2014 (has links)
Sistemas redundantes sujeitos à inspeção periódica são amplamente utilizados nas indústrias, especialmente naqueles processos que envolvem alto risco operacional. Inspeções periódicas são realizadas a fim de identificar e recuperar eventuais falhas de componentes antes da falha do sistema. Inspeções frequentes melhoram a confiabilidade e disponibilidade do sistema, mas envolvem maiores custos de manutenção preventiva. Por outro lado, períodos longos entre inspeções diminuem os custos com inspeções, mas aumentam os riscos de falha do sistema. Desta forma, o principal objetivo deste trabalho é a análise de confiabilidade e a otimização do intervalo entre inspeções de sistemas redundantes sujeitos a inspeções periódicas, a fim de garantir a confiabilidade desejada, juntamente com o menor custo possível. Para analisar a confiabilidade de sistemas redundantes aplicados na prática, inicialmente é realizada uma pesquisa para a identificação dos tipos e características de sistemas redundantes utilizados pelas empresas e dos métodos empregados para a manutenção desses sistemas. Identificadas suas deficiências, um modelo inicial de fácil aplicação que melhore a confiabilidade dos sistemas redundantes estudados é determinado. Na sequência, são desenvolvidos modelos mais sofisticados para a otimização do intervalo entre inspeções, através da minimização dos custos totais envolvidos na manutenção, a fim de garantir a competitividade do processo sem sacrificar a sua confiabilidade. Visto que o reparo imediato é uma suposição que não reflete totalmente a realidade, a próxima etapa envolve a consideração do tempo de reparo para a incrementação do modelo. Por fim, o aprimoramento do modelo envolve a introdução de degradação nos componentes do sistema, que passam a envelhecer com o tempo, aumentando sua taxa de falha. Como resultados têm-se: a elaboração de um quadro comparativo de tipos de redundâncias e métodos de análise de confiabilidade e gestão da manutenção utilizados e recomendados, o desenvolvimento de tabelas e gráficos de simples utilização que permitem a determinação do intervalo entre inspeções mais adequado e o desenvolvimento de um método para otimização do intervalo entre inspeções de sistemas com e sem tempo de reparo e que sofrem ou não degradação, através da minimização dos custos totais de manutenção. / Redundant systems subject to periodic inspections are utilized to decrease high levels of operational risk across different industries. Periodic inspections are utilized to identify and rectify component failures before complete system failure. Frequent inspections improve the system reliability and availability, but require higher preventive maintenance costs. On the other hand, long periods between inspections decrease inspection costs while also increasing the risk of system failure. The main objective of this thesis is to optimize the time intervals between periodic inspections of redundant systems to ensure the required reliability at the lowest cost possible. To analyze the reliability of redundant systems used in real situations, interviews were conducted with maintenance managers from industry leading companies. These interviews identified the types, characteristics, and maintenance methods of the redundant systems that are actually used at these firms. Once their deficiencies were identified, an initial model to improve the redundant system’s reliability was created. Next, more sophisticated models were developed to optimize the time interval between inspections which minimized maintenance costs. Given that instantaneous repair cannot be assumed in many situations, the next step integrated time to repair into the model as a random variable. Finally, the model was further improved by taking into consideration systems comprised of components that degrade over time, thus increasing their failure rate. Redundant systems subject to periodic inspections are utilized to decrease high levels of operational risk across different industries. Periodic inspections are utilized to identify and rectify component failures before complete system failure. Frequent inspections improve the system reliability and availability, but require higher preventive maintenance costs. On the other hand, long periods between inspections decrease inspection costs while also increasing the risk of system failure. The main objective of this thesis is to optimize the time intervals between periodic inspections of redundant systems to ensure the required reliability at the lowest cost possible. To analyze the reliability of redundant systems used in real situations, interviews were conducted with maintenance managers from industry leading companies. These interviews identified the types, characteristics, and maintenance methods of the redundant systems that are actually used at these firms. Once their deficiencies were identified, an initial model to improve the redundant system’s reliability was created. Next, more sophisticated models were developed to optimize the time interval between inspections which minimized maintenance costs. Given that instantaneous repair cannot be assumed in many situations, the next step integrated time to repair into the model as a random variable. Finally, the model was further improved by taking into consideration systems comprised of components that degrade over time, thus increasing their failure rate
48

Uma contribuição para a análise da confiabilidade de sistemas redundantes com inspeção periódica

Mendes, Angélica Alebrant January 2014 (has links)
Sistemas redundantes sujeitos à inspeção periódica são amplamente utilizados nas indústrias, especialmente naqueles processos que envolvem alto risco operacional. Inspeções periódicas são realizadas a fim de identificar e recuperar eventuais falhas de componentes antes da falha do sistema. Inspeções frequentes melhoram a confiabilidade e disponibilidade do sistema, mas envolvem maiores custos de manutenção preventiva. Por outro lado, períodos longos entre inspeções diminuem os custos com inspeções, mas aumentam os riscos de falha do sistema. Desta forma, o principal objetivo deste trabalho é a análise de confiabilidade e a otimização do intervalo entre inspeções de sistemas redundantes sujeitos a inspeções periódicas, a fim de garantir a confiabilidade desejada, juntamente com o menor custo possível. Para analisar a confiabilidade de sistemas redundantes aplicados na prática, inicialmente é realizada uma pesquisa para a identificação dos tipos e características de sistemas redundantes utilizados pelas empresas e dos métodos empregados para a manutenção desses sistemas. Identificadas suas deficiências, um modelo inicial de fácil aplicação que melhore a confiabilidade dos sistemas redundantes estudados é determinado. Na sequência, são desenvolvidos modelos mais sofisticados para a otimização do intervalo entre inspeções, através da minimização dos custos totais envolvidos na manutenção, a fim de garantir a competitividade do processo sem sacrificar a sua confiabilidade. Visto que o reparo imediato é uma suposição que não reflete totalmente a realidade, a próxima etapa envolve a consideração do tempo de reparo para a incrementação do modelo. Por fim, o aprimoramento do modelo envolve a introdução de degradação nos componentes do sistema, que passam a envelhecer com o tempo, aumentando sua taxa de falha. Como resultados têm-se: a elaboração de um quadro comparativo de tipos de redundâncias e métodos de análise de confiabilidade e gestão da manutenção utilizados e recomendados, o desenvolvimento de tabelas e gráficos de simples utilização que permitem a determinação do intervalo entre inspeções mais adequado e o desenvolvimento de um método para otimização do intervalo entre inspeções de sistemas com e sem tempo de reparo e que sofrem ou não degradação, através da minimização dos custos totais de manutenção. / Redundant systems subject to periodic inspections are utilized to decrease high levels of operational risk across different industries. Periodic inspections are utilized to identify and rectify component failures before complete system failure. Frequent inspections improve the system reliability and availability, but require higher preventive maintenance costs. On the other hand, long periods between inspections decrease inspection costs while also increasing the risk of system failure. The main objective of this thesis is to optimize the time intervals between periodic inspections of redundant systems to ensure the required reliability at the lowest cost possible. To analyze the reliability of redundant systems used in real situations, interviews were conducted with maintenance managers from industry leading companies. These interviews identified the types, characteristics, and maintenance methods of the redundant systems that are actually used at these firms. Once their deficiencies were identified, an initial model to improve the redundant system’s reliability was created. Next, more sophisticated models were developed to optimize the time interval between inspections which minimized maintenance costs. Given that instantaneous repair cannot be assumed in many situations, the next step integrated time to repair into the model as a random variable. Finally, the model was further improved by taking into consideration systems comprised of components that degrade over time, thus increasing their failure rate. Redundant systems subject to periodic inspections are utilized to decrease high levels of operational risk across different industries. Periodic inspections are utilized to identify and rectify component failures before complete system failure. Frequent inspections improve the system reliability and availability, but require higher preventive maintenance costs. On the other hand, long periods between inspections decrease inspection costs while also increasing the risk of system failure. The main objective of this thesis is to optimize the time intervals between periodic inspections of redundant systems to ensure the required reliability at the lowest cost possible. To analyze the reliability of redundant systems used in real situations, interviews were conducted with maintenance managers from industry leading companies. These interviews identified the types, characteristics, and maintenance methods of the redundant systems that are actually used at these firms. Once their deficiencies were identified, an initial model to improve the redundant system’s reliability was created. Next, more sophisticated models were developed to optimize the time interval between inspections which minimized maintenance costs. Given that instantaneous repair cannot be assumed in many situations, the next step integrated time to repair into the model as a random variable. Finally, the model was further improved by taking into consideration systems comprised of components that degrade over time, thus increasing their failure rate
49

Closed-form Inverse Kinematic Solution for Anthropomorphic Motion in Redundant Robot Arms

January 2013 (has links)
abstract: As robots are increasingly migrating out of factories and research laboratories and into our everyday lives, they should move and act in environments designed for humans. For this reason, the need of anthropomorphic movements is of utmost importance. The objective of this thesis is to solve the inverse kinematics problem of redundant robot arms that results to anthropomorphic configurations. The swivel angle of the elbow was used as a human arm motion parameter for the robot arm to mimic. The swivel angle is defined as the rotation angle of the plane defined by the upper and lower arm around a virtual axis that connects the shoulder and wrist joints. Using kinematic data recorded from human subjects during every-day life tasks, the linear sensorimotor transformation model was validated and used to estimate the swivel angle, given the desired end-effector position. Defining the desired swivel angle simplifies the kinematic redundancy of the robot arm. The proposed method was tested with an anthropomorphic redundant robot arm and the computed motion profiles were compared to the ones of the human subjects. This thesis shows that the method computes anthropomorphic configurations for the robot arm, even if the robot arm has different link lengths than the human arm and starts its motion at random configurations. / Dissertation/Thesis / M.S.Tech Mechanical Engineering 2013
50

Uma contribuição para a análise da confiabilidade de sistemas redundantes com inspeção periódica

Mendes, Angélica Alebrant January 2014 (has links)
Sistemas redundantes sujeitos à inspeção periódica são amplamente utilizados nas indústrias, especialmente naqueles processos que envolvem alto risco operacional. Inspeções periódicas são realizadas a fim de identificar e recuperar eventuais falhas de componentes antes da falha do sistema. Inspeções frequentes melhoram a confiabilidade e disponibilidade do sistema, mas envolvem maiores custos de manutenção preventiva. Por outro lado, períodos longos entre inspeções diminuem os custos com inspeções, mas aumentam os riscos de falha do sistema. Desta forma, o principal objetivo deste trabalho é a análise de confiabilidade e a otimização do intervalo entre inspeções de sistemas redundantes sujeitos a inspeções periódicas, a fim de garantir a confiabilidade desejada, juntamente com o menor custo possível. Para analisar a confiabilidade de sistemas redundantes aplicados na prática, inicialmente é realizada uma pesquisa para a identificação dos tipos e características de sistemas redundantes utilizados pelas empresas e dos métodos empregados para a manutenção desses sistemas. Identificadas suas deficiências, um modelo inicial de fácil aplicação que melhore a confiabilidade dos sistemas redundantes estudados é determinado. Na sequência, são desenvolvidos modelos mais sofisticados para a otimização do intervalo entre inspeções, através da minimização dos custos totais envolvidos na manutenção, a fim de garantir a competitividade do processo sem sacrificar a sua confiabilidade. Visto que o reparo imediato é uma suposição que não reflete totalmente a realidade, a próxima etapa envolve a consideração do tempo de reparo para a incrementação do modelo. Por fim, o aprimoramento do modelo envolve a introdução de degradação nos componentes do sistema, que passam a envelhecer com o tempo, aumentando sua taxa de falha. Como resultados têm-se: a elaboração de um quadro comparativo de tipos de redundâncias e métodos de análise de confiabilidade e gestão da manutenção utilizados e recomendados, o desenvolvimento de tabelas e gráficos de simples utilização que permitem a determinação do intervalo entre inspeções mais adequado e o desenvolvimento de um método para otimização do intervalo entre inspeções de sistemas com e sem tempo de reparo e que sofrem ou não degradação, através da minimização dos custos totais de manutenção. / Redundant systems subject to periodic inspections are utilized to decrease high levels of operational risk across different industries. Periodic inspections are utilized to identify and rectify component failures before complete system failure. Frequent inspections improve the system reliability and availability, but require higher preventive maintenance costs. On the other hand, long periods between inspections decrease inspection costs while also increasing the risk of system failure. The main objective of this thesis is to optimize the time intervals between periodic inspections of redundant systems to ensure the required reliability at the lowest cost possible. To analyze the reliability of redundant systems used in real situations, interviews were conducted with maintenance managers from industry leading companies. These interviews identified the types, characteristics, and maintenance methods of the redundant systems that are actually used at these firms. Once their deficiencies were identified, an initial model to improve the redundant system’s reliability was created. Next, more sophisticated models were developed to optimize the time interval between inspections which minimized maintenance costs. Given that instantaneous repair cannot be assumed in many situations, the next step integrated time to repair into the model as a random variable. Finally, the model was further improved by taking into consideration systems comprised of components that degrade over time, thus increasing their failure rate. Redundant systems subject to periodic inspections are utilized to decrease high levels of operational risk across different industries. Periodic inspections are utilized to identify and rectify component failures before complete system failure. Frequent inspections improve the system reliability and availability, but require higher preventive maintenance costs. On the other hand, long periods between inspections decrease inspection costs while also increasing the risk of system failure. The main objective of this thesis is to optimize the time intervals between periodic inspections of redundant systems to ensure the required reliability at the lowest cost possible. To analyze the reliability of redundant systems used in real situations, interviews were conducted with maintenance managers from industry leading companies. These interviews identified the types, characteristics, and maintenance methods of the redundant systems that are actually used at these firms. Once their deficiencies were identified, an initial model to improve the redundant system’s reliability was created. Next, more sophisticated models were developed to optimize the time interval between inspections which minimized maintenance costs. Given that instantaneous repair cannot be assumed in many situations, the next step integrated time to repair into the model as a random variable. Finally, the model was further improved by taking into consideration systems comprised of components that degrade over time, thus increasing their failure rate

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