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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.
111

An Analysis of The Effect of 3-D Groove Insert Design on Chip Breaking Chart

Avanessian, Alfred 25 January 2005 (has links)
Abstract Prediction of chip-breaking in machining is an important task for automated manufacturing. There are chip-breaking limits in machining chip-breaking chart, which determine the chip-breaking range. This thesis presents a study of the effect of 3-D groove insert parameters on chip breaking chart. Based on the chip-breaking criteria, the critical feed rate is formulated through an analysis of up-curl chip formation for 3-D grooves. Also in order to predict chip-breaking limits, for protruded insert grooves in finish machining, analytical models are established. In the analytical models, minimum and maximum depth of cut are identified for using different chip breaking models. As well insert nose radius effects on chip thickness for small depth of cut are studied. In the end, the analytical critical feed rate model is extended to finish machining with 3-D chipbreaking grooves.
112

Uso do diagrama sequencial funcional como linguagem de programação para um robô cílindrico (sic) de 5 graus de liberdade acionado pneumaticamente

Leonardelli, Pablo January 2015 (has links)
O presente trabalho tem como objetivo o desenvolvimento de uma estratégia de programação para um robô de cinco graus de liberdade com acionamento pneumático. A proposta para tal estratégia de programação utiliza como base a linguagem SFC (Sequential Function Chart) normatizada pela IEC 61131-3. A principal característica deste tipo de linguagem é a simplicidade na integração com diversos elementos presentes em ambiente fabril, juntamente a garantia do sequenciamento das ações e a facilidade de programação. O estudo foi realizado em três etapas: a primeira, destina-se à criação de sub-rotinas em linguagem SFC para movimentação ponto a ponto, pick and place, e paletização. Desta forma, através da definição de alguns dados de entrada, é possível reprogramar o robô de forma gráfica e intuitiva; a segunda etapa do estudo constituiu na criação de um Programa Tradutor em linguagem baseada em scripts de Matlab que, através de um servidor OPC (Ole for Process Control), faz a interpretação do programa em linguagem SFC e o traduz para a linguagem do sistema de controle do robô; já, a última etapa destina-se à realização de testes utilizando um CLP Compact Logix da AllenBradley em conjunto com o software de programação RSLogix 5000, o software Matlab e o sistema de controle do robô pneumático. A partir dos resultados, Conclui-se que a aplicação e utilização este tipo de programação para tarefas de movimentação de robôs é plenamente viável, o que pode vir a simplificar as etapas de programação, e ampliando a integração entre os diversos sistemas fabris, na medida em que os seus elementos poderão trocar facilmente informações necessárias à automação. / The present study has as main goal to present a differentiated form of programming for a prototype of a robot of five degrees of freedom with pneumatic drive. This program is based on the language SFC (Sequential Function Chart) standardized by IEC 61131-3. The main feature of this type of language is simplicity in integration with various elements present in the manufacturing environment, ensuring the sequencing of actions and ease of programming. The system used as a test bench consists of a pneumatic robot which currently control actions are carried out through specific programming routines combined with dedicated control boards, working with Matlab software. The study was conducted in three stages: the first, for creating subroutines in SFC language to linear movement, pick and place movement and palletizing movement, thus, by setting some input data it is possible to reprogram the robot for tasks in a graphical and intuitive way; the second stage of the study consisted in creating a translator program in Matlab language based on scripts that, through an OPC server (Ole for Process Control), interpreters the program in SFC language and translates it into the language of the control system robot; the last step was intended for testing this programming approach by using a PLC Compact Logix from Allen-Bradley in conjunction with RSLogix 5000 programming software, Matlab and the control system of the pneumatic robot. It was concluded that the implementation and use of this type of programming for robot handling tasks are both feasible. It simplifies the programming steps and enhances the integration between the various manufacturing systems, since the elements could directly exchange information, because they are in the same language.
113

Fundamental Study For Supplier Quality Improvement at AP&T Presses AB Sweden

Yah, Fritz Alum, Che, Jian January 2008 (has links)
This thesis aims at securing the quality of components from AP&T’s suppliers and to get a picture of different suppliers’ processes. In this thesis, samples supplied by various AP&T suppliers where measured at AP&T to gather data on how well the parts met design specifications. The collected data were analyzed using histogram and stratification. Further analysis was done using pareto chart and capability indices. Only the critical dimensions identified from the pareto chart together with discussions with experts on the shop floor were further analyzed using capability indices. This was done to focus more on the critical dimensions which needed more attention. The findings were critically studied and suggestions were made which served as a fundamental base for supplier product quality improvement plan at AP&T. However, there was no direct contact with the supplier process to ascertain its being in control; therefore, product characterization was carried out. In this case, all the results obtained from the analyses only gave a momentary picture of the process. Therefore, the results can not be used for future predictions.In the analysis, special attention was laid on the shape, spread and centering of the histogram. Studies were also done on the significant few; got from the pareto chart. Use was made of capability indices to get the momentary fall-outs of ppm and the percentage of the specification band used up by the process. / Uppsatsnivå: D
114

Análise da amplitude de abertura bucal e seu enquadramento em tabelas de quantificação do dano odontológico / Analysis of the amplitude of buccal opening and its framing in tables of quantification of dental damage

Rosa, Gabriela Cauduro da 02 February 2018 (has links)
Introdução: A região da face corresponde a parte do corpo mais atingida em casos de traumas. Isso ocorre por ser uma área sem proteção e de localização favorável. Traumas nessa região tem como principais causas acidente de trânsito, quedas ou agressões. A consequência mais prevalente é a fratura na região mandibular. Em decorrência disso, é possível perceber diversos prejuízos, dentre eles a limitação na abertura bucal. No entanto, para que seja definido um dano é necessário que se conheça o padrão de normalidade. O Código Civil brasileiro aponta que todo o dano causado por ato ilícito deve ser reparado proporcionalmente ao prejuízo criado na vítima. A utilização de tabelas na quantificação do dano corporal tem sido um elemento importante para a unificação da linguagem e dos critérios, permitindo que uma mesma situação seja avaliada e entendida de forma semelhante. Objetivo: a) Obter a média de abertura bucal de uma população brasileira associando com sexo, idade, estatura e perfil facial; b) Correlacionar a média de abertura bucal de pacientes considerados dentro do padrão de normalidade e pacientes com fratura mandibular; c) Correlacionar os valores de abertura bucal obtidos na pesquisa com a Tabela Nacional de Avaliação de Incapacidades Permanentes em Direito Civil da legislação portuguesa, a tabela brasileira SUSEP e a tabela DPVAT; d) Elaborar uma fórmula para a determinação da redução de abertura bucal. Metodologia: Um questionário relacionado a percepção de dor foi aplicado em pacientes do grupo controle e pacientes analisados em um hospital de São Paulo com fratura de mandíbula. Na sequência, foi verificada a abertura bucal máxima com um paquímetro e tomadas as medidas do terço médio e inferior para determinação do tipo de perfil facial. Além disso, através de um estadiômetro, foi medida a estatura. Os dados foram analisados estatisticamente e relacionados com as três tabelas citadas. Resultados: A média de abertura bucal no sexo masculino foi de 51,71 mm enquanto no sexo feminino foi de 47,94 mm onde foi encontrada correlação positiva entre sexo e abertura bucal. Entretanto não foi possível estabelecer significância com as demais variáveis. Quanto aos pacientes com fratura de mandíbula, a média de abertura bucal para homens foi de 38,91 mm e em mulheres de 41 mm, a etiologia mais prevalente foi acidentes automobilísticos e o local mais acometido foi na região condilar. Conclusão: Foi possível encontrar associação positiva com o sexo, onde homens tendem a ter uma abertura bucal maior que mulheres; Não foi encontrada relação significativa com idade, estatura e perfil facial; Pacientes com fratura mandibular possuem uma amplitude de abertura menor que pacientes considerados dentro dos padrões de normalidade; As tabelas brasileiras, DPVAT e SUSEP são insuficientes para valorar danos odontológicos e a tabela da legislação portuguesa necessita de adaptações e com base nas médias de abertura bucal obtidas, foram elaborada as seguintes fórmulas para o cálculo de redução de abertura bucal, onde para pacientes do sexo masculino usa-se RA=[100-(A.1,93) ] .0,3 e para o sexo feminino RA=[100-(A.2,08) ] .0,3 . / Background: The face is the body part most commonly affected in cases of trauma, since it is an unprotected and vulnerable area. Facial traumas are caused mainly by traffic accidents, falls, or physical assault. Mandibular fracture is the most prevalent consequence of these events. This type of fracture causes some damage, including limited mouth opening. However, in order to define this damage, it is necessary to know what the normal pattern is. The Brazilian Civil Code establishes that any harm caused by the practice of an illicit act must be repaired proportionately to the injury inflicted on the victim. The use of rating charts for quantification of bodily harm has played an important role in standardizing both the language and criteria, thus allowing one to assess and understand the same situation in a similar fashion. Objective: a) To estimate the mean jaw range of motion of the Brazilian population by associating it with sex, age, height, and facial profile; b) to correlate patients with a normal jaw range of motion with those with mandibular fracture; c) to correlate jaw range of motion in the Portuguese National Rating Chart for Permanent Disability Assessment with that in the Brazilian SUSEP and DPVAT charts; d) to develop a formula for limited mouth opening estimation. Method: A pain perception questionnaire was applied to patients from the control group and to those with mandibular fracture assessed at a hospital in the city of São Paulo, Brazil. Maximum mouth opening was measured with a caliper, whereas middle and lower third measurements were made to determine the type of facial profile. Height was measured using a stadiometer. The data were analyzed statistically and compared with those described in the three rating charts. Results: The mean jaw range of motion was 51.71 mm in male patients and 47.94 mm in female patients, and there was a positive correlation between sex and mouth opening. It was not possible to determine the significance of mouth opening relative to the other variables. In patients with mandibular fracture, the mean jaw range of motion was 38.91 mm for men and 41 mm for women; vehicle motor accidents were the major cause of the trauma; and the mandibular condyle was the most frequently affected site. Conclusion: There was a positive correlation with sex, as men tend to have a greater jaw range of motion than women. There was no significant correlation with age, height, and facial profile. Patients with mandibular fracture have a smaller jaw range of motion than those who fall into normal standards. Brazilian charts, DPVAT and SUSEP, are inefficient in rating dental damage, whereas the Portuguese chart requires some adaptations. The following formulas were developed based on the mean jaw range of motion measurements, and they allow estimating limited mouth opening: LMO=[100-(MO x 1.93)] x 0.3 for men and LMO=[100-(MO x 2.08)] x 0.3 for women.
115

Analysis of the condensation problem on the inner surface of Fullriggaren's large vertical window

Castro Herce, Anabel January 2013 (has links)
This Thesis is focused on the study of the problem of condensation on the inner surface of Fullrigaren building’s large single pane window. This has serious consequences as water on the floor, corrosion or mould growth. As the climate in Nordic countries is cold for several months a year, windows are a crucial part in building envelopes. Condensation on a window may be suitably discussed only with respect to the climate considered as cold, moderate and warm climates pose different requirements on the windows, and this is why a characterization of Gävle by its climate is necessary. This Thesis will include the energy analysis of the staircase considered which is required to understand the source of the actual problem. Both heat and moisture transfer will be studied. In this purpose, an IDA model will be built to simulate the conditions throughout the year and hand-made calculations will be done for the average and most critical situations. The results show that condensation will already occur for the monthlyaverage conditions having as an additional problem that if temperature drops below zero it will freeze. Results will also be compared to an initial installation of a 2 pane window reaching as a conclusion that its original installation would had avoided the problems for most of the time. The Thesis will end with several proposals posed to solve the problem by either increasing the temperature or reducing the moisture content of the ambient air, and the selection of the best one. The final aim of the Thesis is to achieve an energy efficient window which should provide good lighting during the day and good thermal comfort both during day and night at minimum demand of paid energy. And for this, the selection of the electrically heated window is proposed.
116

Visualization of Statistical Contents

Mehmood, Raja Majid, Iqbal, Gulraiz January 2010 (has links)
Our project presents the research on visualization of statistical contents. Here wewill introduce the concepts of visualization, software quality metrics andproposed visualization technique (line chart). Our aim to study the existingvisualization techniques for visualization of software metrics and then proposedthe visualization approach that is more time efficient and easy to perceive byviewer.In this project, we focus on the practical aspects of visualization of multipleprojects with respect to the versions and metrics. This project also gives animplementation of proposed visualization techniques of software metrics. In thisresearch based work, we have to compare practically the proposed visualizationapproaches. We will discuss the software development life cycle of our proposedvisualization system, and we will also describe the complete softwareimplementation of implemented software.
117

A statistical process control approach for network intrusion detection

Park, Yongro 13 January 2005 (has links)
Intrusion detection systems (IDS) have a vital role in protecting computer networks and information systems. In this thesis we applied an SPC monitoring concept to a certain type of traffic data in order to detect a network intrusion. We developed a general SPC intrusion detection approach and described it and the source and the preparation of data used in this thesis. We extracted sample data sets that represent various situations, calculated event intensities for each situation, and stored these sample data sets in the data repository for use in future research. A regular batch mean chart was used to remove the sample datas inherent 60-second cycles. However, this proved too slow in detecting a signal because the regular batch mean chart only monitored the statistic at the end of the batch. To gain faster results, a modified batch mean (MBM) chart was developed that met this goal. Subsequently, we developed the Modified Batch Mean Shewhart chart, the Modified Batch Mean Cusum chart, and the Modified Batch Mean EWMA chart and analyzed the performances of each one on simulated data. The simulation studies showed that the MBM charts perform especially well with large signals ?the type of signal typically associated with a DOS intrusion. The MBM Charts can be applied two ways: by using actual control limits or by using robust control limits. The actual control limits must be determined by simulation, but the robust control limits require nothing more than the use of the recommended limits. The robust MBM Shewhart chart was developed based on choosing appropriate values based on batch size. The robust MBM Cusum chart and robust MBM EWMA chart were developed on choosing appropriate values of charting parameters.
118

The Design and Analysis of a Meander Delay Line in a High Speed Digital System

Sun, Hung-wen 25 June 2004 (has links)
Small size of electronic product with high layout density is the future trend in today¡¦s high speed digital circuit design. A circuit designer is obliged to optimize the best solution of circuit layout in a limited area in order to both keep a good signal integrity¡]SI¡^, and save the layout space. Meander delay line is one of the challenging topic in high-speed circuit. In this dissertation, a effective method is provided to design a meander delay line, and FDTD and HFSS are matched up to predict the behavior and the character of the meander delay line; the differential meander delay line is compared with the single meander delay line, and the behavior and phenomena of the differential meander delay line are discussed. To reduce couple power, the differential meander line of design would be a new thinking. The most important point in this thesis, the complete flows of designing single meander lines and differential meander lines are provided, and designer could follow the steps of the proposed method to design a perfect and practical meander line with both keeping good SI and using least layout space. The effect of the design parameters of the meander line on the signal quality both in time-domain and frequency-domain is theoretically and experimentally investigated. FDTD method and the commercial tool HFSS are employed for the numerical study in this work.
119

Coupling Speech Recognition And Rule-based Machine Translation

Kopru, Selcuk 01 September 2008 (has links) (PDF)
The objective of this thesis was to study the coupling of automatic speech recognition (ASR) systems with rule-based machine translation (MT) systems. In this thesis, a unique approach to integrating ASR with MT for speech translation (ST) tasks was proposed. The proposed approach is unique, essentially because it includes the rst rule-based MT system that can process speech data in a word graph format. Compared to other rule-based MT systems, our system processes both a word graph and a stream of words. Thus, the suggested integration method of the ASR and the rule-based MT system is more detailed than a simple software engineering practice. The second reason why it is unique is because this coupling approach performed better than the rst-best and N-best list techniques, which are the only other methods used to integrate an ASR with a rule-based MT system. The enhanced performance of the coupling approach was verified with experiments. The utilization of rule-based MT systems for ST tasks is important / however, there are some unresolved issues. Most of the literature concerning coupling systems has focused on how to integrate ASR with statistical MT rather than rule-based MT. This is because statistical MT systems can process word graphs as input, and therefore, the resolution of ambiguities can be moved to the MT component. With the new approach proposed in this thesis, this same advantage exists in rule-based MT systems. The success of such an approach could facilitate the efficient usage of rule-based systems for ST tasks.
120

Computer-Aided Design for High Speed Spindle System with Angular Contact Ball Bearing

Lin, Jui-De 02 July 2002 (has links)
The aim of this thesis is to develop a Computer-aided Design software for high speed angular contact ball bearing system. First, to analyze the interaction of among the characteristics and parameters of a high-speed spindle system with angular contact ball bearing. These analyses were based on the kinematics of bearing systems and rotor dynamics. According to these analyses, several design charts for bearing system will be established by computer simulations. Secondly, an optimum design for high speed spindle system will also be proposed. After these analyses, an Computer-Aided Design software for high speed bearing system will be established. From the study, preliminary design trends about high speed spindle system will be proposed.

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