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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.
161

A material based approach to creating wear resistant surfaces for hot forging

Babu, Sailesh, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xxii, 185 p.; also includes graphics (some col.). Includes bibliographical references (p. 178-185).
162

A manufacturing strategy : fuzzy multigoal mathematical programming to the Stanely cordless power tools /

Lee, Pui-hung, Johnelly. January 1993 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1993.
163

An analysis of the reasons students enroll in the Machine Tool Operation and Tool & Die Making diploma program at Waukesha County Technical College

Biro, Michael A. January 2006 (has links) (PDF)
Thesis PlanB (M.S.)--University of Wisconsin--Stout, 2006. / Includes bibliographical references.
164

LabelMe: a database and web-based tool for image annotation

Russell, Bryan C., Torralba, Antonio, Murphy, Kevin P., Freeman, William T. 08 September 2005 (has links)
Research in object detection and recognition in cluttered scenes requires large image collections with ground truth labels. The labels should provide information about the object classes present in each image, as well as their shape and locations, and possibly other attributes such as pose. Such data is useful for testing, as well as for supervised learning. This project provides a web-based annotation tool that makes it easy to annotate images, and to instantly sharesuch annotations with the community. This tool, plus an initial set of 10,000 images (3000 of which have been labeled), can be found at http://www.csail.mit.edu/$\sim$brussell/research/LabelMe/intro.html
165

Study of a Parent-Completed Developmental Screening Inventory

Bae, Hyeyoung, 1959- 12 1900 (has links)
xv, 170 p. A print copy of this title is available from the UO Libraries, under the call number: KNIGHT LB1131 .B14 2007 / Many research studies in early childhood assessment have addressed the importance of quality assessment services. Such services involve gathering information on children through direct observation of functional skills in natural settings, which requires considerable time and effort. Due to the unavailability of sufficient resources for the quality assessment services, a new approach needs to be undertaken. Current research has suggested that parent-completed screening utilizing parental knowledge about their child is valid and reliable in appraising current and observable behaviors (Bodnarchuk & Eaton, 2004; O'Neill, 2007). There has been, however, little investigation on in-depth standardized assessments completed by parents for young children aged 18 to 36 months. This study examined validity and reliability of in-depth parental report on child development with the Ages and Stages Questionnaire Inventory for Toddlers (ASQ-IT) for children aged 18-36 moths old. Fifty child-caregiver dyads were divided into two groups, non-risk and risk based on environmental factors including maternal age at the child's birth, family income, and maternal education. In examining psychometric information of the parent-completed measure, acceptable outcomes were found. Accuracy was supported by two examinations for concurrent validity; (1) the Battelle Developmental Inventory, 2nd Edition (BDI-2) administered by professionals and the ASQ-IT completed by parents (r = .63 -.83,p < .01), and (2) the same two measures completed by professionals (r = .72 -.92,p < .01). Findings of both reliability studies, test-retest reliability with the ASQ-IT completed by parents, and inter-observer reliability between parents and professionals, suggested substantial consistency, p = .79 -.93 and p = .65 -.88 respectively. In differential item functioning (DIF) (i.e., 3% of DIF items) and known-group validity analyses (p < .0005 at 36 months), the ability of the ASQ-IT to detect changes in the children's development was confirmed. Results from the social validity examining parent perception of the ASQIT completion identified efficiency of the ASQ-IT (e.g., reasonable time to complete) as well as many benefits. / Adviser: Jane K. Squires
166

Machining surfaces of optical quality by hard turning

Knuefermann, Markus M. W. January 2003 (has links)
The main aim of this work was the machining by hard turning of surfaces with optical surface quality. A numerical target had been set as a surface roughness Ra = 10nm. It has been shown that achieving roughness of that magnitude by hard turning is possible. Individual work pieces exhibited the desired surface properties for short lengths at a time, but it proved to be very difficult to achieve these surfaces consistently and over longer cuts. The factors influencing the surface roughness were identified as tool defects and machine vibration in addition to the standard cutting parameters and choice of cutting tool. A model of surface generation in hard turning has been developed and good correlation between simulated and experimentally determined surface roughnesses was achieved. By introducing a material partition equation which determines the proportional contribution of material removal mechanisms in the undeformed chip a comprehensive method for assessing the contributing factors in material removal was developed. While it has been shown that surfaces in hard turning are almost exclusively generated by chip removal and plastic deformation the developed model is versatile enough to include elastic deformation of the work piece. With the help of the model of surface generation in hard turning it has been possible to attribute magnitudes of the influencing factors with respect to the cutting parameters such as feed rate and tool corner radius, and the main disturbances - tool defects and machine vibration. From this conclusions were drawn on the requirements for machine tools and cutting tools, which will need to be realised to make ultra-precision hard turning of surfaces of optical quality a feasible manufacturing process.
167

Financial feasibility of investing in bulk soybean infrastructure: the case of an Evergreen Seed Agent

Bethany, Huls January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Keith Harris / For an Evergreen Seed Agent, making the financial decision to invest in bulk infrastructure is a large capital investment and requires a great deal of considerations. This thesis determines the soybean sales volume required for an investment in bulk soybean infrastructure to become financially feasible. A total of 1,456 soybean sales data points were used to run a regression model. Based on the results of the regression model, a correlation was determined between those agents that have bulk soybeans and soybean sales growth in comparison to those agents that did not have bulk soybeans. A “Bulk Soybean Decision Tool” was constructed and demonstrates costs and earnings of an Evergreen Seed Agent over a five-year period. The financial feasibility analysis concluded that the soybean volume required to consider investing in bulk soybeans is 8,488 units. In addition to a break-even analysis, three other base year volume scenarios were demonstrated. At the 3,233 unit base soybean sales volume, it is not financially feasible to invest in bulk. At the 10,265 unit base soybean sales volume, it is finically feasible to invest in bulk soybeans. Lastly, at the 18,912 unit base soybean sales volume, it is finically feasible to invest in bulk soybean infrastructure. The capabilities of the “Bulk Soybean Decision Tool” are significant for any Evergreen Seed Agent considering investing in bulk soybean infrastructure. Ensuring that an Evergreen Seed Agent is making a sound financial investment in bulk soybean infrastructure will allow for an increased adoption in infrastructure, resulting in increased soybean sales volume across the distribution network.
168

Processo para obtenção de furos quadrados utilizando máquinas ferramentas CNC com ferramenta em rotação / Process to get square holes by machine tools CNC with tool in rotation

Castro, Marcelo Hirai 21 August 2018 (has links)
Orientador: Amauri Hassui / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-21T02:13:50Z (GMT). No. of bitstreams: 1 Castro_MarceloHirai_M.pdf: 4008200 bytes, checksum: a0c71450e4b5c3ac934e22f6e3cc9f4b (MD5) Previous issue date: 2012 / Resumo: A inovação é a chave para o diferencial da indústria no mercado competitivo atual. Fazer diferente, melhor e mais barato sempre agrega valor ao produto. Por outro lado, a resistência às mudanças faz parte do comportamento humano, seja na sociedade, ou na indústria. O objetivo principal deste trabalho é estudar a viabilidade de se fazer furos não cilíndricos com uma ferramenta em rotação utilizando máquinas-ferramenta CNC. Estes sempre foram obstáculos na indústria de fabricação pela dificuldade de obtenção. Sendo assim, o processo apresentado nesse trabalho busca usinar um furo quadrado com a mesma configuração de ferramentas e fixação de peças utilizadas para um furo cilíndrico, tão comum à indústria. Isso visa reduzir custos de fabricação e facilitar a obtenção de furos não cilíndricos com os recursos de equipamentos programáveis existentes no chão de fábrica. A partir de um modelo matemático, a máquina é programada para executar movimentos sincronizados entre a rotação e os deslocamentos do eixo da ferramenta. Diversas programações foram testadas em diferentes máquinas ferramenta CNC, com diferentes comandos, com e sem recursos de alta velocidade, com diferentes quantidades de pontos programados, interpolações lineares e circulares. A partir dos experimentos, foram analisadas as configurações das máquinas, a capacidade de execução do controlador numérico instalado, a velocidade desenvolvida pela máquina na operação e a geometria obtida dos furos quadrados. Os experimentos apontam que para executar o furo quadrado, os comandos devem ser capazes de controlar um eixo rotativo como eixo propriamente dito, além de sincronizarem mais três eixos lineares. O crítico para este tipo de operação é a velocidade desempenhada pela máquina, sendo o fator mais significativo, o tempo que o comando precisa para o processamento do bloco de programação, independentemente da ativação de recursos de alta velocidade, interpolações lineares ou circulares. Verificou-se também que quanto maior a quantidade de pontos para compor a trajetória do centro da ferramenta, melhor será a geometria obtida do furo. Sendo assim, as máquinas ferramenta CNC que estão em operação na indústria são capazes de realizar a furação não cilíndrica de forma muito próxima à furação cilíndrica quanto ao tempo de usinagem e ao sistema de fixação da ferramenta e da peça, sendo necessária uma programação sincronizada do eixo spindle presente em toda e qualquer máquina ferramenta / Abstract: The innovation is the key for the differential of the industry on the competitive market nowadays. To make different, better and cheaper always it is worth a lot to the product. By the other side, the resistance to changes makes part of the human behavior, in society, or in the industry. The main goal of this work is to study the feasibility to machining of non-cylindrical holes by a tool in rotation using CNC machine tools. That always has been offering obstacles to manufacturing industry by the difficulty of fabrication. Thus, the process presented on this work will machining a square hole with the same configuration of tools and systems for fixation of the parts, used for a cylindrical drilling, so common to industry. This intends to reduce the costs of fabrication and make easier to get non-cylindrical drilling using resources of the programmable equipment which are working at the shops. From a math model on, the machine is programmed to execute synchronized movements between the rotation and the displacements of the axis of the tool. Different programs were tested in different CNC machine tools, with different controllers, with and no resources for high speed, with different quantity of programmed points, with linear and circular interpolations. From the experiments, it was analyzed the configuration of the machines, the capacity for execution of the controller installed, the speed developed by machine at the operation and the geometry of the square holes. The experiments show that to machine a square hole, the controllers must be able to control a rotating axis itself, beyond to synchronize three axis. The critical to this kind of operation is the speed developed by the machine, being the most significant factor, the time the controller needs to process the block of programming, independently the activation of resources for high speed, linear or circular interpolations. It was verified than as larger the amount of points to compose the trajectory of the center of tool, better will be the geometry of the hole. Thus, the CNC machine tools in operation in the industry are able to machine the non-cylindrical drilling in a way very closely the cylindrical drilling as the time of machining and the fixing system of the tool and parts, requiring a programming that synchronizes the main spindle installed in any machine tool / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica
169

Corporate governance and product innovation in the machine-tool sector in Italy

Visintin, Francesca January 2002 (has links)
In this thesis we study the influence of corporate governance on product innovation in the machine-tool sector in Italy. The theoretical framework employed in the analysis is part of the Systems of Innovation literature. It can be defined as a "national-technological system of innovation" type of approach as it distinguishes between countries with different systems of corporate governance and between sectors that employ different technologies. The main hypothesis is that variations in national systems of corporate governance can help to explain national patterns of sectoral specialisation. The thesis focuses on the Italian National System of Innovation from the point of view of its corporate governance. The main characteristics of the system are analysed in the first part of the thesis where it is also shown how they can help to explain the Italian industrial specialisation. The study proceeds with an application of the theoretical framework to the analysis of the machine-tool sector, its technology and its historical evolution. A particular focus is put on the decline of the US in the sector during the 1970s and 1980s and the corresponding upsurge of Japan. The final part of the thesis studies the Italian System of Innovation in the machine-tool sector. It highlights that firms are not the only actors in the System and that other stakeholders, such as customers and suppliers, play an important part in the innovation process. It shows also that the system presents some weaknesses, consisting mainly of the lack of financial resources, that need to be resolved. Our final argument, supported by an econometric analysis, is that one of the solutions suggested by the machine-tool builders association, namely a wave of mergers and acquisitions, is not necessarily the best answer. A stronger coordination and cooperation among competing and non-competing firms appears to be the most incisive solution from the point of view of innovation for this sector.
170

Supporting conceptual queries over integrated sources of program information

De Alwis, Brian 05 1900 (has links)
A software developer explores a software system by asking and answering a series of questions. To answer these questions, a developer may need to consult various sources providing information about the program, such as the static relationships expressed directly in the source code, the run-time behaviour of a program recorded in a dynamic trace, or evolution history as recorded in a source management system. Despite the support afforded by software exploration tools, developers often struggle to find the necessary information to answer their questions and may even become disoriented, where they feel mentally lost and are uncertain of what they were trying to accomplish. This dissertation advances a thesis that a developer's questions, which we refer to as conceptual queries, can be better supported through a model to represent and compose different sources of information about a program. The basis of this model is the sphere, which serves as a simple abstraction of a source of information about a program. Many of the software exploration tools used by a developer can be represented as a sphere. Spheres can be composed in a principled fashion such that information from a sphere may replace or supplement information from a different sphere. Using our sphere model, for example, a developer can use dynamic runtime information from an execution trace to replace information from the static source code to see what actually occurred. We have implemented this model in a configurable tool, called Ferret. We have used the facilities provided by the model to implement 36 conceptual queries identified from the literature, blogs, and our own experience, and to support the integration of four different sources of program information. Establishing correspondences between similar elements from different spheres allows a query to bridge across different spheres in addition to allowing a tool's user interface to drive queries from other sources of information. Through this effort we show that sphere model broadens the set of possible conceptual queries answerable by software exploration tools. Through a small diary study and a controlled experiment, both involving professional software developers, we found the developers used the conceptual queries that were available to them and reported finding Ferret useful. / Science, Faculty of / Computer Science, Department of / Graduate

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