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The information era has brought upon us waves of change that brings affordable technology Within the reach of the average person. Computers connected to the Internet, part of our daily living, have led to the formation of online communities. In the spirit of communal efforts, a community cannot be controlled or managed into a specific form or direction. A community has a need to concentrate its efforts towards a common goal or vision, therefore sufficiently nonrestrictive infrastructure is needed to enable the community members to contribute towards their goal. We design and build infrastructure to support a virtual community, according to the needs of the community. Community members can easily locate and exchange files among each other, interact in private and public chat rooms by means of instant text messages, as well as make announcements and participate in group discussions in a Web based environment. Additional needs are identified and tended to by means of various value adding services. We also formulate a management strategy to lead the community towards self-sustenance / Thesis (M. Ing. (Computer and Electronical Engineering))--North-West University, Potchefstroom Campus, 2009.

The information era has brought upon us waves of change that brings affordable technology Within the reach of the average person. Computers connected to the Internet, part of our daily living, have led to the formation of online communities. In the spirit of communal efforts, a community cannot be controlled or managed into a specific form or direction. A community has a need to concentrate its efforts towards a common goal or vision, therefore sufficiently nonrestrictive infrastructure is needed to enable the community members to contribute towards their goal. We design and build infrastructure to support a virtual community, according to the needs of the community. Community members can easily locate and exchange files among each other, interact in private and public chat rooms by means of instant text messages, as well as make announcements and participate in group discussions in a Web based environment. Additional needs are identified and tended to by means of various value adding services. We also formulate a management strategy to lead the community towards self-sustenance / Thesis (M. Ing. (Computer and Electronical Engineering))--North-West University, Potchefstroom Campus, 2009.

ABSTRACT DESIGN OF A CONNECTED PIPE TEST FACILITY FOR RAMJET APPLICATIONS SARISIN, Mustafa Nevzat M.S., Department of Mechanical Engineering Supervisor: Asst. Prof. Dr. Abdullah ULAS Co-Supervisor: Prof. Dr. Kahraman ALBAYRAK April 2005, 164 pages Development of the combustor of a ramjet can be achieved by connected pipe testing. Connected pipe testing is selected for combustor testing because pressure, temperature, Mach number, air mass flow rate can be simulated by this type of testing. Real time trajectory conditions and transition from rocket motor (booster) to ramjet operation can also be tested. The biggest advantage of connected pipe testing is the low operation cost and simplicity. Air mass flow rate requirement is less than the others which requires less air storage space and some components like supersonic nozzle and ejector system is not necessary. In this thesis, design of a connected pipe test facility is implemented. Three main systems are analyzed / air storage system, air heater system and test stand. Design of air storage system includes the design of pressure vessel and pressure &amp / flow regulation system. Pressure and flow regulation system is needed to obtain the actual flow properties that the combustor is exposed to during missile flight. Alternatives for pressure and air mass flow rate regulation are considered in this study. Air storage system designed in this thesis is 27.8 m3 at 50 bar which allows a test duration of 200 seconds at an average mass flow rate of 3 kg/s. Air heater system is utilized to heat the air to simulate the aerodynamic heating of the inlet. Several different combustion chamber configurations with different flame holding mechanisms are studied. The most efficient configuration is selected for this study. Combustion analysis of the air heater is performed by FLUENT CFD Code. Combustion process and air heater designs are validated using experimental data. Designed air heater system is capable of supplying air at a temperature range of 400-1000 K and mass flow rate range of 1.5-8 kg/s at Mach numbers between 0.1-0.5 and pressure between 2-8 bar. Finally the design of the test stand and ramjet combustor analysis are completed. 3D CAD models of the test stand are generated. Ramjet combustor that will be tested in the test setup is modeled and combustion analysis is performed by FLUENT CFD Code. The ramjet engine cruise altitude is 16 km and cruise Mach number is 3.5. Key-words: Air Breathing Engines, Ramjet, Connected Pipe, Direct Connect, Vitiator.

Η παρούσα διπλωματική εργασία έχει ως αντικείμενο αφενός την μελέτη και επισκόπηση των υπαρχόντων κοινωνικών δικτύων και την καταγραφή των πληροφοριών που παρέχουν, αφετέρου δε την ανάπτυξη μιας εφαρμογής κοινωνικής δικτύωσης, η οποία θα αποτελείται από δύο μέρη.Το πρώτο μέρος έχει την μορφή ενός tutorila των APIs τεσσάρων μεγάλων κοινωνικών δικτύων: Facebook, Twitter, Linkedin, Google Friend Connect. Το δεύτερο μέρος παρέχει στον χρήστη την δυνατότητα συνάθροισης και προβολής των δεδομένων του που προέρχονται από τα προφίλ του στα προαναφερθέντα κοινωνικά δίκτυα. / The scope of this thesis is firstly to study and review of existing social networks and record the information they provide, and secondly, to develop a social networking application which will consist of two parts. The first part takes the form of an APIs tutorial of four large socila networks: Facebook, Twitter,Linkedin, Google Friend Connect. The second part provides the user the ability to gather and display the data from the profiles of the aforementioned social networks.

Made available in DSpace on 2017-07-10T18:01:54Z (GMT). No. of bitstreams: 1 Andreia Peiter.pdf: 1366062 bytes, checksum: e0b82884da5c768cb61affcb50cffecf (MD5) Previous issue date: 2015-07-27 / According on the demand for processes that minimize the environmental impact generated by waste, efficient systems that make possible the degradation of these compounds and allow its use as an alternative source for renewable energy generation are increasingly required. The increasing food production to meet the needs of the world population has encouraged the use of agrochemicals in order to ensure productivity in crops. The use of insecticides is increasing to control pests and herbicides for weed control, because there is a lack of effective control that includes new production strategies. Techniques such as crop rotation, no-till system introduction and use of green pesticides (natural insecticides) provide a more sustainable agriculture and reduce impacts to the environment. In this context, this work presents an alternative development of an integrated system for remediation of environments contaminated with simultaneous generation of electricity. The materials were prepared from reagents and accessible metals, which reduce costs and contribute to a clean process, without the addition of organic additives. Due to the high oxidizing potential of hydroxyl radicals generated by the pair electron-hole (e+ + h+) in the semiconductors, was possible to degrade the organic compounds used in the system. The results showed that the generation of current in an area of 6,9 cm2 was 193,37 uA in potassium hydrogen phthalate degradation, using Cu/CuO electrode as a photocatalyst. The Aminol® and Connect® pesticides have been degraded at a percentage of 54,46% and 21,02%, respectively, after 1 hour and 30 minutes in the system, under ultraviolet radiation. The degradation of organic contaminants and simultaneous power generation of energy in integrated system provides a self-sustaining form of wastewater treatment and energy recovery, being possible its use on a large scale. / Em função da demanda por processos que minimizem os impactos ambientais gerados por resíduos, sistemas eficientes que possibilitem a degradação desses compostos e permitam sua utilização como fonte alternativa para geração de energia renovável são cada vez mais requeridos. A crescente produção de alimentos para suprir as necessidades da população mundial tem incentivado o emprego de agroquímicos com o objetivo de assegurar a produtividade nas lavouras. Cada vez mais aumenta o uso de inseticidas para o controle de pragas e herbicidas para o controle de ervas daninhas, pois há carência de um controle efetivo que inclua novas estratégias de produção. Técnicas como rotação de cultura, introdução do sistema de plantio direto e utilização de inseticidas verdes (inseticidas naturais) propiciam uma agricultura mais sustentável e reduzem os impactos causados ao ambiente. Nesse contexto, o presente trabalho apresenta uma alternativa de desenvolvimento de um sistema integrado para remediação de ambientes contaminados com geração simultânea de energia elétrica. Os materiais foram preparados a partir de reagentes e metais acessíveis, os quais reduzem os custos e contribuem para um processo mais limpo, sem a ação de aditivos orgânicos. Devido ao alto potencial oxidante dos radicais hidroxila gerados por meio do par elétron-lacuna (e- + h+) em semicondutores, foi possível degradar os compostos orgânicos utilizados no sistema. Os resultados mostraram que a geração de corrente em uma área de 6,9 cm2 foi de 193,37 µA na degradação do padrão hidrogenoftalato de potássio, utilizando eletrodo de Cu/CuO como fotocatalisador. Os agrotóxicos Aminol 806® e Connect® foram degradados com percentual de 54,46% e 21,02%, respectivamente, após 1 hora e 30 minutos no sistema, sob radiação ultravioleta. A degradação de contaminantes orgânicos e simultânea geração de energia no sistema integrado prevê uma forma autossustentável de tratamento de efluentes e recuperação de energia, sendo possível sua utilização em grande escala.