Development of dry coal feeders

Design and fabrication of equipment of feed coal into pressurized environments were investigated. Concepts were selected based on feeder system performance and economic projections. These systems include: two approaches using rotating components, a gas or steam driven ejector, and a modified standpipe feeder concept. Results of development testing of critical components, design procedures, and performance prediction techniques are reviewed

J2EE application for clustered servers : focus on balancing workloads among clustered servers : a thesis presented in partial fulfilment of the requirements for the degree of Master of Information Science in Computer Science at Massey University, Albany, New Zealand

J2EE has become a de facto platform for developing enterprise applications not only by its standard based methodology but also by reducing the cost and complexity of developing multi-tier enterprise applications. J2EE based application servers keep business logic separate from the front-end applications (client-side) and back-end database servers. The standardized components and containers simplify J2EE application design. The containers automatically manage the fundamental system level services for its components, which enable the components design to focus on the business requirement and business logic. This study applies the latest J2EE technologies to configure an online benchmark enterprise application - MG Project. The application focuses on three types of components design including Servlet, entity bean and session bean. Servlets run on the web server Tomcat, EJB components, session beans and entity beans run on the application server JBoss and the database runs on the database server Postgre SQL. This benchmark application is used for testing the performance of clustered JBoss due to various load-balancing policies applied at the EJB level. This research also focuses on studying the various load-balancing policies effect on the performance of clustered JBoss. As well as the four built-in load-balancing policies i.e. First Available, First Available Identical All Proxies, Random Robin and Round Robin, the study also extend the JBoss Load balance Policy interface to design two dynamic load-balancing policies. They are dynamic and dynamic weight-based load-balancing policies. The purpose of dynamic load-balancing policies design is to ensure minimal response time and obtain better performance by dispatching incoming requests to the appropriate server. However, a more accurate policy usually means more communications and calculations, which give an extra burden to a heavily loaded application server that can lead to drops in the performance

Electromagnetic procedures to support main components design of synchronous machines

Synchronous generators have proven over the decades to be the feasible solution for three-phase power systems and have consolidated as the vital piece in power plants in which the source of energy is renewable, as hydraulic or wind. Thus, with a constant increase in environmental concerns in current times, it is also expected an increase in synchronous machine usage, along with more research and development. A challenge would be to integrate the traditional consolidated knowledge with modern computational tools. Since when it comes to electrical machines, there is more than one procedure or technique to solve the same question, many combinations of new algorithms and books from a century ago have yet space to be approached. This work proposes and develops a set of tools to allow the analysis of magnetics effects in a salient pole machine with general, accurate, and fast solutions, applying what has been taught for the first “machinerists”, as Tingley and Park, alongside with MATLAB and Finite Element Method. Its objectives are to get Magnetomotive Force and Magnetic Flux Density of a given machine so then, in future work, to calculate the inductance matrix. MMF is calculated through Tingley Box, Winding Matrix, and Fourier Series, allowing the analysis for every single turn. Flux density is calculated through Finite Element Analysis, which allows the calculation of enclosure factors that support the accuracy of the tool by comparing it with manufacturers' benchmarks. In the end, a guide in MATLAB is shown, which aggregates everything exposed with a user-friendly interface.Os geradores síncronos provaram ao longo das décadas ser a solução viável para sistemas elétricos trifásicos e se consolidaram como peça vital em usinas em que a fonte de energia é renovável, como hidráulica ou eólica. Assim, com um aumento constante das preocupações ambientais nos tempos atuais, também se espera um aumento no uso de máquinas síncronas, juntamente com mais pesquisa e desenvolvimento. Um desafio seria integrar o conhecimento tradicional consolidado com ferramentas computacionais modernas. Já que, quando se trata de máquinas elétricas, existe mais de um procedimento ou técnica para resolver a mesma questão, muitas combinações de novos algoritmos e livros de um século atrás ainda têm espaço para serem abordadas. Este trabalho propõe e desenvolve um conjunto de ferramentas para permitir a análise de efeitos magnéticos em uma máquina de pólo saliente com soluções gerais, precisas e rápidas, aplicando o que foi ensinado pelos primeiros “maquinistas”, como Tingley e Park, ao lado do MATLAB e Método dos Elementos Finitos. Seus objetivos são obter a Força Magnetomotriz e a Densidade do Fluxo Magnético de uma determinada máquina para então, em trabalhos futuros, calcular a matriz de indutância. O MMF é calculado por meio de Tingley Box, Matriz de enrolamento e Série de Fourier, permitindo a análise para cada curva. A densidade do fluxo é calculada por meio da Análise de Elementos Finitos, que permite o cálculo dos fatores de invólucro que suportam a precisão da ferramenta, comparando-a com os benchmarks dos fabricantes. Ao final, é apresentado um guia em MATLAB, que agrega tudo o que está exposto em uma interface amigável

Car Steering Components Design

Práce se zabývá návrhem a konstrukcí komponent sestavy řízení závodního monopostu Formule Student. Hlavními komponenty jsou hřeben řízení s tělesem částečně vyrobeným z uhlíkového kompozitu a kuželová převodka řízení se zakřivenými zuby. Součásti práce je i návrh uložení jednotlivých komponent. Práce se zabývá také možnostmi využití sloupku řízení z uhlíkového kompozitu.The aim of this bachelor thesis is construction of steering components for Formula Student monopost. Main components are steering rack with body partially made from carbon composite and bevel gearbox with Gleason gears. Part of this work is design of supports of those components. The work also deals with possibilities of usage of steering column made of carbon composite.

Space Shuttle Tail Service Mast Concept Verification

Design studies and analyses were performed to describe the loads and dynamics of the space shuttle tail service masts (TSMs). Of particular interest are the motion and interaction of the umbilical carrier plate, lanyard system, vacuum jacketed hoses, latches, links, and masthead. A development test rig was designed and fabricated to obtain experimental data. The test program is designed to (1) verify the theoretical dynamics calculations, (2) prove the soundness of design concepts, and (3) elucidate problem areas (if any) in the design of mechanisms and structural components. Design, fabrication, and initiation of TSM development testing at Kennedy Space Center are described

Applying tropos to socio-technical system design and runtime configuration

Recent trends in Software Engineering have introduced the importance of reconsidering the traditional idea of software design as a socio-tecnical problem, where human agents are integral part of the system along with hardware and software components. Design and runtime support for Socio-Technical Systems (STSs) requires appropriate modeling techniques and non-traditional infrastructures. Agent-oriented software methodologies are natural solutions to the development of STSs, both humans and technical components are conceptualized and analyzed as part of the same system. In this paper, we illustrate a number of Tropos features that we believe fundamental to support the development and runtime reconfiguration of STSs. Particularly, we focus on two critical design issues: risk analysis and location variability. We show how they are integrated and used into a planning-based approach to support the designer in evaluating and choosing the best design alternative. Finally, we present a generic framework to develop self-reconfigurable STSs

Sketchnote Components, Design Space Dimensions, and Strategies for Effective Visual Note Taking

Sketchnoting is a form of visual note taking where people listen to, synthesize, and visualize ideas from a talk or other event using a combination of pictures, diagrams, and text. Little is known about the design space of this kind of visual note taking. With an eye towards informing the implementation of digital equivalents of sketchnoting, inking, and note taking, we introduce a classification of sketchnote styles and techniques, with a qualitative analysis of 103 sketchnotes, and situated in context with six semi-structured follow up interviews. Our findings distill core sketchnote components (content, layout, structuring elements, and visual styling) and dimensions of the sketchnote design space, classifying levels of conciseness, illustration, structure, personification, cohesion, and craftsmanship. We unpack strategies to address particular note taking challenges, for example dealing with constraints of live drawings, and discuss relevance for future digital inking tools, such as recomposition, styling, and design suggestions

Separator development and testing of nickel-hydrogen cells

The components, design, and operating characteristics of Ni-H2 cells batteries were improved. A separator development program was designed to develop a separator that is resistant to penetration by oxygen and loose active material from then nickel electrode, while retraining the required chemical and thermal stability, reservoir capability, and high ionic conductivity. The performance of the separators in terms of cell operating voltage was to at least match that of state-of-the-art separators while eliminating the separator problems. The separators were submitted to initial screening tests and those which successfully completed the tests were built into Ni-H2 cells for short term testing. The separators with the best performance are tested for long term performance and life

Formula Student Drivetrain Components Design

Práce se zabývá popisem hnacího ústrojí formulového vozidla. Poznatky z teoretického rozboru v úvodu práce jsou použity v konstrukční části zabývajícího se návrhem komponentů vozidla Formule Student. S konstrukčním návrhem souvisí výpočet zátěžných stavů hnacího ústrojí, pevnostní výpočet hnacích hřídelí, unašečů homokinetických kloubů a příruby rozety. Navržené komponenty jsou řešeny pomocí metody konečných prvků v programu Ansys Workbench.This batchelor´s thesis deals with description of formula student drivetrain components. Knowledge acquired in the theoretical part is applied in construction part of thesis. With structural design relates determination of drivetrain loading, stress analysis of driveshafts, stub axles and sprocket´s flange. All components were designed by using finite element method in software Ansys Workbench.