This study was an historical garment study that investigated the similarities and differences between variables for thread characteristics, such as thread configuration, degree of twist, direction of twist, color, and color match grades of sewing thread used in assembling American women's dresses and suits during the time period between 1880 and 1909. Items were selected using a convenience sampling from the Smithsonian Institution, National Museum of American History, in Washington, DC, and The Valentine Museum in Richmond, Virginia. A total of 417 observations were collected from 39 garments. Noninvasive procedures were used to examine late nineteenth and early twentieth century garments and record sewing thread characteristics from multiple designated locations. Research objectives of the study included: 1) documentation of thread characteristics for machine-sewn seams, 2) documentation of thread characteristics for handsewn seams or stitchings, and 3) documentation of dominant thread characteristics by five year periods. Frequency distributions and frequency distribution tables were completed. The results of this study revealed widespread use of one basic type of sewing thread for the total sample during the time period 1880-1909. Characteristics of threads used in handsewn and machine-sewn seams or stitchings were 3/2-cord thread with high degree of twist and S direction of twist. It appeared that aesthetic concerns for color differences and matching contrasts of thread with the fashion fabric did not always coincide with use of threads with high strength. Data analyses revealed recurring patterns. Results found for year to year observations were consistent with results found within the five year group increments. Dominant thread characteristics found within the group observations for chain stitch thread characteristics were also present in the lockstitch group observations and machine-sewn group observations. Patterns noted in observations for handsewn seams or stitchings were also similar to those found in machine-sewn seams. Noninvasive methods were used for collection of data during the study. Methods used included naked-eye visual observations and hand-held microscope observations for recording seam, stitch, and thread characteristics. / Master of Science

Recent trends in the computer market suggest that emerging computing platforms will be increasingly parallel and heterogeneous, in order to satisfy the user demand for improved performance and superior energy savings. Heterogeneity is a promising technology to keep growing the number of cores per chip without breaking the power wall. However, existing system software is able to cope with homogeneous architectures, but it was not designed to run on heterogeneous architectures, therefore, new system software designs are necessary. One innovative design is the multikernel OS deployed by the Barrelfish operating system (OS) which partitions hardware resources to independent kernel instances that communicate exclusively by message passing, without exploiting the shared memory available amongst different CPUs in a multicore platform. Popcorn Linux implements an extension of the multikernel OS design, called replicated-kernel OS, with the goal of providing a Linux-based single system image environment on top of multiple kernels, which can eventually run on different ISA processors. A replicated-kernel OS replicates the state of various OS sub-systems amongst kernels that cooperate using message passing to distribute or access various services uniquely available on each kernel. In this thesis, we present mechanisms to distribute signals, namespaces, inter-thread synchronizations and socket state replication. These features are built on top of the existing messaging layer, process or thread migration and address space consistency protocol to provide the application with an illusion of single system image and developers with the SMP programming environment they are most familiar with. The mechanisms developed were unit tested with micro benchmarks to validate their correctness and to measure the gained speed up or additive overhead. Real-world applications were also used to benchmark the developed mechanisms on homogeneous and on heterogeneous architectures. It is found that the contributed Popcorn synchronization mechanism exhibits overhead compared to vanilla Linux on multicore as Linux's equivalent mechanisms are tightly coupled with underlying hardware cache coherency protocol, therefore, faster than software message passing. On heterogeneous platforms, the developed mechanisms allow to transparently map each portion of the application to the processor in the platform on which the execution is faster. Optimizations are recommended to further improve the performance of the proposed synchronization mechanism. However, optimizations may force the userspace application and libraries to be rewritten in order to decouple their synchronization mechanisms of shared memory, therefore losing transparency, which is one of the primary goals of this work. / Master of Science

Product lifecycles are complex heterogeneous systems. Applying control methods to lifecycles requires significant human capital. Additionally, measuring lifecycles relies primarily on domain expertise and estimates. Presented in this dissertation is a way to semantically represent a product lifecycle as a cyber-physical system for enabling the application of control methods to the lifecycle. Control requires a model and no models exist currently that integrate each phase of lifecycles. The contribution is an integration framework that brings all phases and systems of a lifecycle together. First presented is a conceptual framework and technology innovation. Next, linking product lifecycle data dynamical is described and then how that linked data could be certified and traced for trustworthiness. After that, discussion is focused how the trusted linked data could be combined with machine learning to drive applications throughout the product lifecycle. Last, a case study is provided that integrates the framework and technology. Integrating all of this would enable efficient and effective measurements of the lifecycle to support prognostic and diagnostic control of that lifecycle and related decisions. / Ph. D. / The manufacturing sector is on a precipice to disruptive change that will signifcantly alter the way industrial organizations think, communicate, and interact. Industry has been chasing the dream of integrating and linking data across the product lifecycle and enterprises for decades. However, inexpensive and easy to implement technologies to integrate the people, processes, and things across various enterprises are still not available to the entire value stream. Industry needs technologies that use cyber-physical infrastructures efectively and efciently to collect and analyze data and information across an enterprise instead of a single domain of expertise. Meeting key technical needs would save over $100 billion annually in emerging advanced manufacturing sectors in the US. By enabling a systems-thinking approach, signifcant economic opportunities can be achieved through an industrial shift from paper-based processes to a digitally enabled model-based enterprise via the digital thread. The novel contribution of this dissertation is a verifed and validated integration framework, using trusted linked-data, that brings all phases and systems of the product lifecycle together. A technology agnostic approach was pursued for dynamically generating links. A demonstration is presented as a reference implementation using currently available technology. Requirements, models, and policies were explored for enabling product-data trustworthiness. All methods were developed around open, consensus-based standards to increase the likelihood of scalability. The expected outcome of this work is efcient and efective measurements of the lifecycle to support data-driven methods, specifcally related to knowledge building, decision support, requirements management, and control of the entire product lifecycle.

Multi-core and many-core systems are the norm in contemporary processor technology and are expected to remain so for the foreseeable future. Parallel programming is, thus, here to stay and programmers have to endorse it if they are to exploit such systems for their applications. Programs using parallel programming primitives like PThreads or OpenMP often exploit coarse-grain parallelism, because it offers a good trade-off between programming effort versus performance gain. Some parallel applications show limited or no scaling beyond a number of cores. Given the abundant number of cores expected in future many-cores, several cores would remain idle in such cases while execution performance stagnates. This thesis proposes using cores that do not contribute to performance improvement for running implicit fine-grain speculative threads. In particular, we present a many-core architecture and protocols that allow applications with coarse-grain explicit parallelism to further exploit implicit speculative parallelism within each thread. We show that complementing parallel programs with implicit speculative mechanisms offers significant performance improvements for a large and diverse set of parallel benchmarks. Implicit speculative parallelism frees the programmer from the additional effort to explicitly partition the work into finer and properly synchronized tasks. Our results show that, for a many-core comprising 128 cores supporting implicit speculative parallelism in clusters of 2 or 4 cores, performance improves on top of the highest scalability point by 44% on average for the 4-core cluster and by 31% on average for the 2-core cluster. We also show that this approach often leads to better performance and energy efficiency compared to existing alternatives such as Core Fusion and Turbo Boost. Moreover, we present a dynamic mechanism to choose the number of explicit and implicit threads, which performs within 6% of the static oracle selection of threads. To improve energy efficiency processors allow for Dynamic Voltage and Frequency Scaling (DVFS), which enables changing their performance and power consumption on-the-fly. We evaluate the amenability of the proposed explicit plus implicit threads scheme to traditional power management techniques for multithreaded applications and identify room for improvement. We thus augment prior schemes and introduce a novel multithreaded power management scheme that accounts for implicit threads and aims to minimize the Energy Delay2 product (ED2). Our scheme comprises two components: a “local” component that tries to adapt to the different program phases on a per explicit thread basis, taking into account implicit thread behavior, and a “global” component that augments the local components with information regarding inter-thread synchronization. Experimental results show a reduction of ED2 of 8% compared to having no power management, with an average reduction in power of 15% that comes at a minimal loss of performance of less than 3% on average.

Capillary electrophoresis chip has gradually ripe along with the development of MEMS technology. However, such these electrophoresis chips was design closed-channel form whose process including the micro-channel forming and chip bonding and so on, so the cost is higher. In addition, if these chips use repeated will cause some pollution problems such as obstruction or difficult to clean in the closed-channel. Therefore, to fabricate a non-closed microfluidic chip system will resolve the issues above listed. In this study has successful developed a convenient and low-cost thread microfluidic system, the thin polyester thread is instead of the traditional closed separation channel. And to avoid the cross contaminations that the separation channel can free replace a new electrophoresis separation channel by the roller equipment. Thread microfluidic systems can take advantage of capillary action to move, as a disposable chromatography flow channel, and the electric field is applied to this system for electrophoresis separation and electrochemical detection in the backend. This research develop an novel process technology, the hot embossing technology shape from concave embossing and metal coating procedure in PMMA, the salient pillow-electrode structure has be produced in PMMA board, the salient electrode structure set up the polyester fiber thread, the polyester fiber thread is as the electrophoresis separation channel, and electrochemical detect samples in back-end. In this study take plasma treatment to improve wettability and surface roughness of the polyester fiber thread, in order to improve the operational effectiveness of the thread microfluidic systems. The cyclic voltammetry measure potassium ferricyanide samples and the results showed that the performance of thread microfluidic system significantly increase after the plasma treatment, the measuring current value is 10 times greater than without the plasma treatment, and the estimated detection limit of potassium ferricyanide is around 6.25 £gM in the plasma treatment one. In addition, the thread microfluidic devices with plasma treatment has successful separation and detection the mixing samples of 0.3 mM chlorine, bromine and iodine ions, and the signal of the S/N ratio is 6 times higher than the without plasma treatment one, and the number of theoretical plates of electrophoresis separation also enhance to 28% in the plasma treatment one. In addition, in order to further enhance the detection sensitivity of the thread microfluidic systems, the study design and fabricate the concave-shaped three-dimensional electrode structure, and to achieve greater contact area between thread and the electrode. Thread microfluidic system with plasma treatment detect in concave-shaped three-dimensional electrode and flat electrode respectively, the results showed that concave-shaped electrodes in the potassium ferricyanide detection limit that measured current value is 10 times greater than flat electrode, and a mixture of dopamine and catechol sample are electrophoresis separated that concave-shaped 3D electrode whose measured S/N ratio is 5 times higher than flat electrode, and the number of theoretical plates is 1.5 times higher than the flat electrode. This study develops a novel thread microfluidic system that will provide a simple process and low-cost, and can solve the shortcomings of conventional closed-channel electrophoresis chips. In future, in this study develop the thread microfluidic system architecture will have contribute for fast electrophoresis separation and detection.

Due to the limitation of single machine¡¦s computing power, and the aspect of cost, distributed design is getting more and more popular nowadays. The Distributed Shared Memory (DSM) system is one of the most hot topics in this area. Most people are dedicated on designing a library or even a new language, in order to gain higher performance on DSM systems. As a consequence, the programmers are required to learn a new library or language. Even more, they have to handle synchronizations for the distributed environment. In this paper, we propose a design that is compatible with POSIX-Thread Environment. The distributed nature of the system described herein is totally transparent to the programmers.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-19T12:18:08Z No. of bitstreams: 1 2014 - Ronilson Rodrigues Pinho.pdf: 623700 bytes, checksum: 7bc5eefc4b9dab2877f833cbdab95b9f (MD5) / Made available in DSpace on 2017-06-19T12:18:08Z (GMT). No. of bitstreams: 1 2014 - Ronilson Rodrigues Pinho.pdf: 623700 bytes, checksum: 7bc5eefc4b9dab2877f833cbdab95b9f (MD5) Previous issue date: 2014-10-06 / The Boundary Element Method (BEM) is a computational method for differential equations solutions, formulated in the form of integral domains. Thus, it is applied in Fluid Mechanics, Acoustics, Electromagnetics and Fractures study. The BEM requires discretization only regarding boundary geometry of the problem, but not inside as a whole, reducing the computational effort. In order to reduce computational effort, parallel computing is an efficient form of information processing emphasizing concurrent events exploitation during software execution. This processing status arises primarily due to high computational performance requirements and difficulty in increasing single processor core speed. Despite central processing units (CPUs), whether multiprocessors or multicore processors, are easily found today, several algorithms are not suitable to run on parallel architectures yet. The present study aimed to develop parallelism research, acting in a sequential program, using Fortran 77 language (VERA-TUDELLA, 2003), making numerical analysis of stress and strain 2D specific problems) of Solids Mechanics with BEM, as well as, its clamped and tensioned bar physical representation. This application implementation is intended to exploit the maximum parallelism / O M?todo de Elementos de Contorno (MEC) ? um m?todo computacional para a solu??o de sistemas de equa??es diferenciais, formuladas em forma de integrais. Aplicado na Mec?nica dos fluidos, Ac?stica, Eletromagn?ticos, Estudo de fraturas etc. O MEC requer discretiza??o apenas no contorno da geometria do problema, mas n?o do seu interior como um todo, diminuindo o esfor?o computacional. Com o intuito em diminuir o esfor?o computacional, a Computa??o paralela ? uma forma eficiente de processamento de informa??o com ?nfase na explora??o de eventos simult?neos na execu??o de um software. Ele surge principalmente devido ?s elevadas exig?ncias de desempenho computacional e ? dificuldade em aumentar a velocidade de um ?nico n?cleo de processamento. Apesar das CPUs multiprocessadas, ou processadores multicore, serem facilmente encontrados atualmente, diversos algoritmos ainda n?o s?o adequados para executar em arquiteturas paralelas. O presente estudo objetivou-se com o intuito de prosseguir na pesquisa sobre paralelismo, atuando num programa sequencial, desenvolvido na linguagem Fortran 77 (VERA-TUDELA, 2003), que efetua an?lises num?ricas de problemas espec?ficos tens?o e deforma??o em 2D) da Mec?nica dos S?lidos via MEC com representa??o f?sica da barra engastada e tracionada. A implementa??o da aplica??o, visa explorar o m?ximo o paralelismo

The thesis deals with an analysis of an existing technology of thread forming under various technological parameters used in car industry. Furthermore, it characterizes metric threads, their production and quality control, forming taps, process fluids and other process parameters. In the experimental part the experimental tests with a conventional and CNC drilling machines were carried out. The influence of various process fluids on surface and thread quality have been assessed statistically. The technical-economic evaluation of the process fluids and their effect on the technology has been made. The work supports a beneficial role of soap and polymers as convenient tribological means at thread forming.

Thread rolling is a unique metal forming process which is commonly used to form screw threads on threaded fasteners and precision leadscrews at relatively high rates of speed. Threads are formed on a cylindrical blank by flat or cylindrical dies having the reverse form on them, which rotate and penetrate the blank simultaneously, to plastically deform it into a precise geometry. Thread rolling dies are exposed to a complex state of cyclical contact stresses that eventually cause the dies to fail by fatigue and wear. The stress state is not easily ascertained through standard analytical models due to complex geometry and process conditions. This research seeks to better understand the state of contact stresses present in cylindrical thread rolling dies as they form material, to aid in identifying and testing economical methods of improving thread rolling die fatigue life. Some work has been published on using FEA simulation software to model the thread rolling process, but no work has been published on using FEA software to analyze the stresses in thread rolling dies. DEFORM®-3D Forming Simulation Software by Scientific Forming Technologies Corporation in Columbus, Ohio was used to simulate the throughfeed thread rolling process and model the state of stresses in the dies. The results were compared to the Hertzian contact stress model and the Smith Liu equations for rolling and sliding friction. Fatigue life prediction methods involving S-N curves, surface fatigue strength, and Weibull probability distributions were tested using the simulation data against field results. An optimized die design was generated from a design of experiments simulating different die design geometry. Findings show that field failures correlate well to the DEFORM® simulation results. The Hertz model with Smith Liu equations improved correlation with the simulation. Fatigue life prediction models correlated reasonably well to field results using the simulation data for inputs. These findings can aid in selecting appropriate die materials, design parameters, and fatigue life treatments.

本報は，雌ねじ切り工具であるスレッドミルを使用した雌ねじ切り加工を研究対象としている．スレッドミル加工の特性やねじ精度について，切削力や加工温度を計測し解析することで検討をおこないその結果を記載している．計測には無線ホルダやサーボドライブユニット等の最新のIoT技術も使用することで，近年増加傾向にあるIoT技術の適応も試みた． / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University