Siga este enlace para ver otros tipos de publicaciones sobre el tema: Radio equipment.
Tesis sobre el tema "Radio equipment"
Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros
Consulte los 50 mejores tesis para su investigación sobre el tema "Radio equipment".
Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.
También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.
Explore tesis sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.
1
Flood, Ian. "Graph theoretic methods for radio equipment selection". Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/50910/.
Texto completoResumen
In the 1970s and 1980s, a small group of American engineers recognised the importance of the graph-colouring ideas studied by mathematicians and the potential for these ideas to be used in practical radio frequency assignment procedures. Some groundbreaking work led to a long period of study in academia where many variants on the Frequency Assignment Problem have been considered and some advanced algorithms developed. This thesis has investigated the Frequency Assignment Problem for microwave fixed links and, taking account of the constraints experienced in professional practice, extended this to include the problem of Equipment Selection. For a particular data-rate, standard radio equipment using relatively lower-or higher order modulation schemes can be deployed by the fixed link operator. While the higher-order options use less bandwidth, they radiate at higher powers and require more protection in the radio interference environment. That is, they are more potent interferers and present a greater challenge to distant interferers. Therefore, when the assigner’s objective is to minimise the span of frequencies used by a network, the higher-order modulation radio is not always the most spectrally efficient. The thesis has hypothesised that by doubling the bandwidth requirement on selected links, the assigner can actually reduce the overall span of frequencies used to support a frequency assignment for the entire network. With a minimum span objective, fixed link deployment scenarios have been exposed to a standard IP Solver that gives exact solutions. Using graph-theoretic methods, equipment selection heuristics have been developed and tested in offline and online environments. This work has gathered significant evidence in support of the hypothesis.
2
Törnberg, Pontus. "GNSS independent navigation using radio navigation equipment". Thesis, Luleå tekniska universitet, Rymdteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81212.
Texto completoResumen
This thesis studies algorithms to estimate an aircraft’s position with different information from various radio stations. Because aircrafts both civilian and military are heavily dependant on GNSS signals, it can be interfered from hostile sources. The aircraft shall then be able to navigate without the GNSS signals. This thesis focuses on three radio navigation systems, DME,VOR and TACAN. With the measurements from these three radio stations and measurements from the inertial navigation system one can estimate a position with an estimation filter. In this thesis two types of filters will be used, the linear Kalman filter and the Extended Kalman filter. The linear Kalman filter will be used when converting the TACAN measurements to a pseudo position and the Extended Kalman filter will be used for the DME,VOR and TACAN measurements. The results shows that the converted TACAN measurements and TACAN measurements estimates very well in both north and east direction. When using only DME measurements the filter estimates the position fairly well in the direction towards the station and poorly in the orthogonal direction. For the VOR measurements the filter estimates the position quite poorly in the direction of the radio station and well in the orthogonal direction. In conclusion the converted TACAN measurement and TACAN measurement algorithm can be used for navigation purposes by its own measurements. However, the DME and VOR measurement algorithms need to be combined or using multiple stations at different locations to get better estimates in both directions. All of the filter could use some better tuning to get the optimal filter, but it is not necessary.
3
Sanchez, Joaquin A., Richard A. Nixon, Sergio Chávez, Joaquin A. Sanchez, Richard A. Nixon y Sergio Chávez. "Medical equipment management through the use of radio frequency identification (RFID)". Thesis, Monterey, California. Naval Postgraduate School, 2004. http://hdl.handle.net/10945/9914.
Texto completoResumen
MBA Professional ReportApproved for public release, distribution is unlimited
MBA Professional Report
Approved for public release, distribution is unlimited
The purpose of this MBA project is to identify the potential value of Radio Frequency Identification (RFID) use in the management of medical equipment at Naval Medical Center San Diego (NMCSD). In doing so, our project seeks to derive potential benefits through the use of RFID technology by comparing a group of medical equipment items that are tracked within NMCSD. The project includes a discussion of additional potential uses of RFID infrastructure within the Military Healthcare System, and possible resulting benefits. Ultimately, the project will determine the financial viability and practicality of implementing RFID.
The purpose of this MBA project is to identify the potential value of Radio Frequency Identification (RFID) use in the management of medical equipment at Naval Medical Center San Diego (NMCSD). In doing so, our project seeks to derive potential benefits through the use of RFID technology by comparing a group of medical equipment items that are tracked within NMCSD. The project includes a discussion of additional potential uses of RFID infrastructure within the Military Healthcare System, and possible resulting benefits. Ultimately, the project will determine the financial viability and practicality of implementing RFID.
4
Latief, Tauriq. "The design of a two-element radio interferometer using satellite TV equipment". Master's thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33756.
Texto completoResumen
This research presents the design of a two-element radio interferometer capable of performing complex correlation. With the development of sophisticated radio astronomy instruments, particularly in South Africa, there is a need to develop an affordable educational instrument which can be used to demonstrate the fundamental concepts of radio interferometry to university students. The mass production of satellite TV equipment has resulted in relatively sensitive radio frequency (RF) equipment such as parabolic reflector dishes and low-noise block down-converters (LNBs) being available at significantly reduced costs. This served as the front-end of the interferometer which was used to observe the sun between 10.70 GHz - 12.75 GHz (RF). The LNB then down-converted these to an intermediate frequency (IF) between 0.95 GHz - 2.15 GHz. The LNBs were modified to make use of a common 25 MHz reference, which ensured that the observed fringes were only as a result of the source's geometric time delay. A power detector was also designed since the adding interferometer architecture was chosen. This power detector included the Analog Devices LT 5534 power detector integrated circuit (IC) and a Teensy 3.6 microcontroller. The calibrated power detector could detect signals as weak as - 60 dBm and showed less than 21 mV error in output for input signals in the range [- 50 dBm, -30 dBm]. The modified LNBs experienced issues, in particular the presence of a spurious LO signal, which distorted initial observations of the sun. This was resolved by the design and manufacture of narrowband hairpin filters and quarterwavelength stub filters which were used to isolate the IF band between 1.05 GHz - 1.15 GHz (corresponding RF between 10.80 GHz - 10.90 GHz). This also improved the interferometer's resolution. A series of filter-integrated Wilkinson power dividers and branchline couplers were designed to filter and further separate signals into in-phase and quadrature-phase (I-Q) components - these were required for complex correlation. The integrated quarter-wavelength stub filter and Wilkinson power divider achieved a maximum amplitude imbalance of 0.13 dB and phase imbalance of 0.9◦ between output ports. The integrated quarter-wavelength stub filter and branchline coupler achieved a maximum amplitude imbalance of 0.13 dB and phase imbalance of 91.1◦ between output ports. These results closely agreed with the simulated performance. First light was observed on the 5th December 2020 when the sun was successfully detected using the coherent two-element interferometer along a 1.1 m baseline. Other tests included using the observed fringe phase to verify the physical baseline. A theoretical baseline of 1.11 m was calculated for a physical baseline of 1.3 m indicating an error of less than 0.2 m. The sun's fringe frequency and amplitude was also observed for varying baselines - the sun was resolved along a 3 m baseline. Finally, full-system observations of the sun were conducted. These included observing the sun's cosine and sine fringes, which indicated that the analogue complex correlator was operating correctly. Thus, the primary goal of this project had been fulfilled. Specifically, developing a low-cost, educational two-element radio interferometer capable of detecting the sun.
5
Aggarwal, Rebecca. "An agent approach to improving radio frequency identification enabled Returnable Transport Equipment". Thesis, Aston University, 2014. http://publications.aston.ac.uk/23175/.
Texto completoResumen
Returnable transport equipment (RTE) such as pallets form an integral part of the supply chain and poor management leads to costly losses. Companies often address this matter by outsourcing the management of RTE to logistics service providers (LSPs). LSPs are faced with the task to provide logistical expertise to reduce RTE related waste, whilst differentiating their own services to remain competitive. In the current challenging economic climate, the role of the LSP to deliver innovative ways to achieve competitive advantage has never been so important. It is reported that radio frequency identification (RFID) application to RTE enables LSPs such as DHL to gain competitive advantage and offer clients improvements such as loss reduction, process efficiency improvement and effective security. However, the increased visibility and functionality of RFID enabled RTE requires further investigation in regards to decision‐making. The distributed nature of the RTE network favours a decentralised decision‐making format. Agents are an effective way to represent objects from the bottom‐up, capturing the behaviour and enabling localised decision‐making. Therefore, an agent based system is proposed to represent the RTE network and utilise the visibility and data gathered from RFID tags. Two types of agents are developed in order to represent the trucks and RTE, which have bespoke rules and algorithms in order to facilitate negotiations. The aim is to create schedules, which integrate RTE pick‐ups as the trucks go back to the depot. The findings assert that: -agent based modelling provides an autonomous tool, which is effective in modelling RFID enabled RTE in a decentralised format utilising the real‐time data facility. ‐ the RFID enabled RTE model developed enables autonomous agent interaction, which leads to a feasible schedule integrating both forward and reverse flows for each RTE batch. ‐ the RTE agent scheduling algorithm developed promotes the utilisation of RTE by including an automatic return flow for each batch of RTE, whilst considering the fleet costs and utilisation rates. ‐ the research conducted contributes an agent based platform, which LSPs can use in order to assess the most appropriate strategies to implement for RTE network improvement for each of their clients.
6
Tigga, Celine. "Modelling of Measurement Equipment for High Frequency Electromagnetic Fields". Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-18894.
Texto completoResumen
The aim of this thesis was to develop a model of a receiver which could be quickly used to analyze radiated interference levels from data captured at the output of the antenna equipment used to measure radiated energy. Active circuits were mainly used in developing this model for the ease with which the design and simulations could be carried out in OrCAD. The guiding document for the thesis work has been CISPR 16-1-1 (International Special Committee on Radio Interference part 16-1-1) which specifies the characteristics and performance of equipment for the measurement of radiated interference. The testing of this receiver model was carried out as far as possible based on the test setups recommended in CISPR, and all results have been compared with the standards laid down for the model. Using the results, it will be shown that a CISPR EMI receiver can be modeled as a simple EMI receiver consisting of filtering, mixing and detecting circuits built according to specifications.
7
Price, Alfred W. "The evolution of electronic warfare equipment and techniques in the USA, 1901 to 1945". Thesis, Loughborough University, 1985. https://dspace.lboro.ac.uk/2134/7410.
Texto completoResumen
This work describes the evolution cf electronic warfare equipment and techniques in the USA, from the first instance of radio jamming in that country in 1901 until the end of World War II in 1945. It begins with a review of early work on telegraph, radio and radar systems throughout the world, and countermeasures used during trials or in combat prior to World War II. Immediately after the USA ertered the conflict in 1941, the Radio Research Laboratory was set up near Boston to develop radio countermeasures equipment for the US armed forces. The organisation rapidly outgrew the capacity of a angle laboratory and in October 1942 Division 15 of the National Defense Research Committee was formed, to co-ordinate US work on countermeasures. The activities of RRL and Division 15 are described in detail, using cortemporary records and accounts from participants. Radar jammers developed by Divison 15 were first used in action in July 1943 during the invason of Sicily, and went on to play important roles in support amphibious landings and strategic bombing operations in the European and Pacific theatres of operations. The jamming devices and tactics employed, the enemy attempts to develop counter-countermeasures and the US moves to counter these counters are all described in detail. Conclusions are drawn on the effectiveness of the various types of jamming, based on post-war interrogation of German and Japanese serving officers and technical personnel. Appendices give technical details of the countermeasures devices produced in the USA during World War II, and the development of radar and radar countermeasures in Germany and Japan.
8
Rosa, Tiago Miguel Simões. "Flexible LTE user equipment". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23753.
Texto completoResumen
Mstrado em Engenharia Eletrónica e TelecomunicaçõesAs redes móveis estão em constante evolução. A geração atual (4G) de redes celulares de banda larga e representada pelo standard Long Term Evolution (LTE), definido pela 3rd Generation Partnership Project (3GPP). Existe uma elevada procura/uso da rede LTE, com um aumento exponencial do número de dispositivos móveis a requerer uma ligação à Internet de alto débito. Isto pode conduzir à sobrelotação do espetro, levando a que o sinal tenha que ser reforçado e a cobertura melhorada em locais específicos, tal como em grandes conferências, festivais e eventos desportivos. Por outro lado, seria uma vantagem importante se os utilizadores pudessem continuar a usar os seus equipamentos e terminais em situações onde o acesso a redes 4G é inexistente, tais como a bordo de um navio, eventos esporádicos em localizações remotas ou em cenários de catástrofe, em que as infraestruturas que permitem as telecomunicações foram danificadas e a cobertura temporária de rede pode ser decisiva em processos de salvamento. Assim sendo, existe uma motivação clara por trás do desenvolvimento de uma infraestrutura celular totalmente reconfigurável e que preencha as características mencionadas anteriormente. Uma possível abordagem consiste numa plataforma de rádio definido por software (SDR), de código aberto, que implementa o standard LTE e corre em processadores de uso geral (GPPs), tornando possível construir uma rede completa investindo somente em hardware - computadores e front-ends de radiofrequência (RF). Após comparação e análise de várias plataformas LTE de código aberto foi selecionado o OpenAirInterface (OAI) da EURECOM, que disponibiliza uma implementação compatível com a Release 8.6 da 3GPP (com parte das funcionalidades da Release 10). O principal objectivo desta dissertação é a implementação de um User Equipment (UE) flexível, usando plataformas SDR de código aberto que corram num computador de placa única (SBC) compacto e de baixa potência, integrado com um front-end de RF - Universal Software Radio Peripheral (USRP). A transmissão de dados em tempo real usando os modos de duplexagem Time Division Duplex (TDD) e Frequency Division Duplex (FDD) é suportada e a reconfiguração de certos parâmetros é permitida, nomeadamente a frequência portadora, a largura de banda e o número de Resource Blocks (RBs) usados. Além disso, é possível partilhar os dados móveis LTE com utilizadores que estejam próximos, semelhante ao que acontece com um hotspot de Wi-Fi. O processo de implementação é descrito, incluindo todos os passos necessários para o seu desenvolvimento, englobando o port do UE de um computador para um SBC. Finalmente, a performance da rede é analisada, discutindo os valores de débitos obtidos.
Mobile networks are constantly evolving. 4G is the current generation of broadband cellular network technology and is represented by the Long Term Evolution (LTE) standard, de ned by 3rd Generation Partnership Project (3GPP). There's a high demand for LTE at the moment, with the number of mobile devices requiring an high-speed Internet connection increasing exponentially. This may overcrowd the spectrum on the existing deployments and the signal needs to be reinforced and coverage improved in speci c sites, such as large conferences, festivals and sport events. On the other hand, it would be an important advantage if users could continue to use their equipment and terminals in situations where cellular networks aren't usually available, such as on board of a cruise ship, sporadic events in remote locations, or in catastrophe scenarios in which the telecommunication infrastructure was damaged and the rapid deployment of a temporary network can save lives. In all of these situations, the availability of exible and easily deployable cellular base stations and user terminals operating on standard or custom bands would be very desirable. Thus, there is a clear motivation for the development of a fully recon gurable cellular infrastructure solution that ful lls these requirements. A possible approach is an open-source, low-cost and low maintenance Software-De ned Radio (SDR) software platform that implements the LTE standard and runs on General Purpose Processors (GPPs), making it possible to build an entire network while only spending money on the hardware itself - computers and Radio-Frequency (RF) front-ends. After comparison and analysis of several open-source LTE SDR platforms, the EURECOM's OpenAirInterface (OAI) was chosen, providing a 3GPP standard-compliant implementation of Release 8.6 (with a subset of Release 10 functionalities). The main goal of this dissertation is the implementation of a exible opensource LTE User Equipment (UE) software radio platform on a compact and low-power Single Board Computer (SBC) device, integrated with an RF hardware front-end - Universal Software Radio Peripheral (USRP). It supports real-time Time Division Duplex (TDD) and Frequency Division Duplex (FDD) LTE modes and the recon guration of several parameters, namely the carrier frequency, bandwidth and the number of LTE Resource Blocks (RB) used. It can also share its LTE mobile data with nearby users, similarly to a Wi-Fi hotspot. The implementation is described through its several developing steps, including the porting of the UE from a regular computer to a SBC. The performance of the network is then analysed based on measured results of throughput.
9
Brown, Keith Edgar. "The application of knowledge-based techniques to fault diagnosis of 16 QAM digital microwave radio equipment". Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/12958.
Texto completo
10
Mainini, Kevin. "Reducing Radio Frequency Susceptibilities in Commercial-Off-the-Shelf Camera Equipment for use in Electromagnetic Compatibility Testing". Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2484.
Texto completoResumen
The Technical Testing and Analysis Center (TTAC) Group at Oak Ridge National Laboratory performs electromagnetic compatibility testing on various radiation detection units. These tests require remote viewing of the equipment’s display to monitor its compliance with national and international standards. The Commercial-Off-the-Shelf (COTS) camera equipment that is used to monitor the displays exhibits radio frequency susceptibilities causing issues when determining the actual susceptibilities of the device under test. In order to mitigate this issue, a COTS camera was placed in two common test positions and cycled through three angled orientations with various radio frequency shielding methods applied. The development of these shielding methods was investigated in this thesis. The goal was to reduce the number of susceptible frequencies. The reduction of susceptibilities would greatly increase the viewing capacity of the cameras during testing. The techniques discovered have allowed for other COTS camera equipment to be modified and used effectively during electromagnetic compatibility testing.
11
Krishnan, Vikram. "A high bit rate flexible MAC protocol for monitoring applications using 60ghz radio technology". Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34707.
Texto completoResumen
In recent years there has been a growing trend in optical wireless convergence.
One particular aspect of this is 60 GHz radio-over-fiber technology. It is intended for use
in wireless personal area networks. However, we think that the same technology could be
used for monitoring applications in the indoor environment. It could be used to detect
emergency situations or to detect intruders. We shall examine reasons why this choice
might be a suitable one. We shall then propose a MAC layer protocol to accomplish this
task. Since in case of emergency we might require to obtain data from only one node for
an extended duration, flexibility in implementation is required. We shall develop an
adaptive MAC protocol where this would be possible. We accomplish this by including
two protocol modes called the Icarus mode, which is to be used in case of an emergency
and the Resync mode which is used when normality is restored. A significant problem at
high frequencies is that the beam becomes increasingly narrow and behaves more in a ray
like condition. This implies that particularly in an indoor environment it is possible that
the beam may be accidentally blocked. In this case the node must be able shift the beam
in order to enable communication. We demonstrate three such strategies and offer a
comparative analysis.
12
Amirante, Robert V. Baker Greggory L. "Feasibility analysis of using microcircuit technology in logistics applications/radio frequency (MITLA/RF) to support equipment maintenance management /". Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA277036.
Texto completo
13
Amirante, Robert V. y Greggory L. Baker. "Feasibility analysis of using microcircuit technology in logistics applications/radio frequency (MITLA/RF) to support equipment maintenance management". Thesis, Monterey, California. Naval Postgraduate School, 1993. http://hdl.handle.net/10945/39655.
Texto completoResumen
Approved for public release; distribution is unlimited.This thesis presents the background, criteria, and baseline recommendations for a Microcircuit Technology in Logistics Application/Radio Frequency (MITLA/RF) proposal to support developing maintenance management doctrine. Its main thrust is a preliminary feasibility analysis of MITLA/RF to identify key issues with regard to maintenance operations within emerging Operational Maneuver From The Sea (OMFTS) concepts. This thesis surveys current requirements, information systems initiatives, test/evaluation results, implementation issues, and technology tradeoffs. It offers alternatives to reliance on manual record keeping and frameworks for enhancing horizontal/ vertical information flows, explores several near real-time interactive decision making tools, and suggests doctrinal improvements through a fusion of procedural and high-tech approaches. This study is an outline for melding policy change with the state-of-the-art technology required to successfully support emerging Combat Service Support (CSS) operations.
14
Van, Wyk John Foster. "Reusable software defined radio platform for micro-satellites". Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1346.
Texto completo
15
Golde, Nico [Verfasser], Jean-Pierre [Akademischer Betreuer] Seifert, Jochen [Akademischer Betreuer] Schiller y Yongdae [Akademischer Betreuer] Kim. "On the impact of modified cellular radio equipment / Nico Golde. Gutachter: Jochen Schiller ; Yongdae Kim. Betreuer: Jean-Pierre Seifert". Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1067387021/34.
Texto completo
16
Євтушенко, Є. А. "Пристрій моніторингу параметрів радіоелектронного апарату". Thesis, Чернігів, 2021. http://ir.stu.cn.ua/123456789/23674.
Texto completoResumen
Євтушенко, Є. А. Пристрій моніторингу параметрів радіоелектронного апарату : випускна кваліфікаційна робота : 172 «Телекомунікації та радіотехніка» / Є. А. Євтушенко ; керівник роботи О. В. Савенко ; НУ "Чернігівська політехніка", кафедра радіотехнічних та вбудованих систем. – Чернігів, 2021. – 53 с.Метою роботи є розробка, проектування та програмування проекту. В роботі були розглянуті існуючі рішення. В дипломному проекті було розроблено схему електричну структурну, схему електричну принципову, схему програми, також було створено друковану плату для схеми електричної принципової. Для схем були проведені розрахунки та було описано принцип їх роботи.
The purpose of the work is the development, design and programming of the project. The existing solutions were considered in the work. In the diploma project the electric structural scheme, the electric basic scheme, the program scheme were developed, the printed circuit board for the electric basic scheme was also created. Calculations were performed for the schemes and the principle of their operation was described.
17
Liu, Van-chee y 廖宏智. "A feasibility study and business proposal for a new comer of CT2 cordless telephone operating company". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31265455.
Texto completo
18
Subramanians, Sankar Saravanan. "Geo-based Mobility Control for Mobile Traffic Simulators". Thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-101979.
Texto completoResumen
Most mobile traffic simulators of today depend on the user to supply the mobility behavior of the simulated UEs. This becomes a problem when certain wanted mobility characteristics are to be tested, since the user have to go trough a trial-and-error procedure to come up with the proper mobility behavior. This thesis presents two approaches to mobility control, where the aim is to control UE mobility based on certain mobility characteristics supplied by the end user. The first approach introduces the concept of assigning tasks to UEs, e.g. “cross cell border†or “move to a certain cellâ€. Furthermore, concepts from control theory are borrowed to control the task assignment process, making it more dynamic and robust. The second approach iteratively calculate movement patterns for the UEs in an area until it finds a movement pattern that has a high probability of satisfying the user’s requested mobility characteristics.
19
Karnstedt, Jonna. "Usability analysis of a telecom Remote Radio Unit and development of mounting equipment : -to facilitate the installation and to reduce errors and time required". Thesis, KTH, Maskinkonstruktion (Inst.), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99441.
Texto completoResumen
Mechanical Design Mast & Wall Mounted Enclosures is one out of five units within Ericsson AB, Network and Enclosure Solutions. The department develops mast and wall mounted products for Radio Base Stations and is responsible for the Remote Radio Unit (RRU), one out of two main units in a main remote radio base configuration. The RRU is designed to be located near the antenna to reduce feeder loss and power use. There are high demands for mast and wall mounted telecommunications products and the handling and installation of the products are key features to meet technical requirements. These operations are not always so intuitive why the product documentation is very important information. Occasionally these instructions are not fully followed. The aim of the master thesis was to analyze how the design of an RRU and the mounting equipment affects the handling and installation of the product, and show that by designing for usability enhance the intuitive sense of how to perform the installation. The thesis follows a user centered design (UCD) process, including four main steps; specify the context of use, specify requirements, create design solutions and evaluate designs , which keep the user in focus through the whole work. The first two steps were done by information gathering and a usability analysis of the RRU. This part contained the handling and installation of the whole RRU, while the development part would only focus on the mounting equipment. Recommendations for future design of RRU‟s regarding usability aspects have been documented. Based on the analysis requirements for the development phase was set up. The most prominent requirements were to design a solution that did not contain loose details such as nuts and bolts, and that it had to be backward compatible to fit elder models. A mounting equipment design was developed and a prototype was produced in order to evaluate the design. Feedback on the design was collected from a usability practice with Ericsson engineers. The final solution of the new mounting equipment is designed to use the same components for both mast- and wall configurations. The design consists of three main components which are all used for mast mounting and where two of the components are used for wall mounting. The design depends on the manufacturing possibilities of extruded aluminum and bent stainless steel as well as on the usability requirements. The final design solution have been documented in this report and submitted in CAD-files to Ericsson.Mechanical Design Mast & Wall Mounted Enclosures är en utav fem avdelningar inom Ericsson AB, Network and Enclosure Solutions. Avdelningen utvecklar mast- och väggmonterade produkter för radiobasstationer och är ansvarig för den radiospecifika enheten, RRU‟n, som är en av två huvudenheter av en Main Remote basstation. RRU‟n är konstruerad för att placeras i närhet av antennen för att reducera förluster i kablarna. Det finns högt satta krav på mast- och väggmonterade telekom-produkter och hanteringen och installationen av dem är nyckelfunktioner för att klara de satta kraven. Produktinformationen är en viktig del av produkten där det framgår hur den skall hanteras och installeras, vilket annars inte alltid är så intuitivt. I vissa fall finns dock inte dokumentationen tillgänglig. Syftet med examensarbetet var att analysera hur konstruktionen av RRU‟n samt mast- och väggfästet påverkar användarvänligheten under hantering och installation, samt visa att genom att designa utifrån användarvänlighet förbättra den intuitiva känslan av hur man utför installationen. Arbetet följde en process med fokus på användaren (User Centered Design) med fyra huvudsteg; specificera användarsambanden, specificera kraven, skapa designlösningar och utvärdera modeller. De första två stegen utfördes genom informationssökning samt genom en användaranalys av RRU‟n och inkluderade hela RRU‟n samt fästanordningen, medan den andra delen av arbetet enbart fokuserade på fästanordningen. Problemområden angående produkterna och rekommendationer för framtida design av en RRU är sammanställda. Krav gällande användarvänlighet vilka baserades på analysen fastställdes. De mest framträdande kraven var att skapa en lösning som inte innehöll lösa detaljer som skruvar och muttrar, och att lösningen måste vara bakåtkompatibel för att passa äldre modeller av RRU‟er. Ett nytt mast- och väggfäste utvecklades och en prototyp tillverkades för att kunna utvärdera designen. En användarövning tillsammans med anställda ingenjörer på Ericsson genomfördes för att erhålla feedback. Den slutliga lösningen av fästanordningen är designat utifrån möjligheten att använda samma komponenter för både mast- och vägginstallation. Produkten består av tre huvudkomponenter varav alla tre används vid mastmontage men enbart två används vid väggmontage. Designen är anpassad efter tillverkningsmöjligheterna av extruderad aluminium och bockad rostfri stålplåt, samt satta användarkrav. Det slutliga konceptet finns dokumenterat i denna rapport samt överlämnat till företaget i CAD-filer.
20
Drury, William B. "A data collection system for the study of RF interference from industrial, scientific, and medical equipment". Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183129782.
Texto completo
21
Simmons, Randall J. Curran Christopher C. "Mesh networks within a distributed operations framework utilizing IP based radios". Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Sep%5FSimmons.pdf.
Texto completoResumen
Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, September 2007.Thesis Advisor(s): Bordetsky, Alex. "September 2007." Description based on title screen as viewed on Oct. 22, 2007. Includes bibliographical references (p. 93-95). Also available in print.
22
Faneuff, Jeffery J. "Spatial, Spectral, and Perceptual Nonlinear Noise Reduction for Hands-free Microphones in a Car". Digital WPI, 2002. https://digitalcommons.wpi.edu/etd-theses/926.
Texto completoResumen
"Speech enhancement in an automobile is a challenging problem because interference can come from engine noise, fans, music, wind, road noise, reverberation, echo, and passengers engaging in other conversations. Hands-free microphones make the situation worse because the strength of the desired speech signal reduces with increased distance between the microphone and talker. Automobile safety is improved when the driver can use a hands-free interface to phones and other devices instead of taking his eyes off the road. The demand for high quality hands-free communication in the automobile requires the introduction of more powerful algorithms. This thesis shows that a unique combination of five algorithms can achieve superior speech enhancement for a hands-free system when compared to beamforming or spectral subtraction alone. Several different designs were analyzed and tested before converging on the configuration that achieved the best results. Beamforming, voice activity detection, spectral subtraction, perceptual nonlinear weighting, and talker isolation via pitch tracking all work together in a complementary iterative manner to create a speech enhancement system capable of significantly enhancing real world speech signals. The following conclusions are supported by the simulation results using data recorded in a car and are in strong agreement with theory. Adaptive beamforming, like the Generalized Side-lobe Canceller (GSC), can be effectively used if the filters only adapt during silent data frames because too much of the desired speech is cancelled otherwise. Spectral subtraction removes stationary noise while perceptual weighting prevents the introduction of offensive audible noise artifacts. Talker isolation via pitch tracking can perform better when used after beamforming and spectral subtraction because of the higher accuracy obtained after initial noise removal. Iterating the algorithm once increases the accuracy of the Voice Activity Detection (VAD), which improves the overall performance of the algorithm. Placing the microphone(s) on the ceiling above the head and slightly forward of the desired talker appears to be the best location in an automobile based on the experiments performed in this thesis. Objective speech quality measures show that the algorithm removes a majority of the stationary noise in a hands-free environment of an automobile with relatively minimal speech distortion."
23
Al-Imari, Aman A. "Etude et réalisation d'une chaîne d'acquisition et de transmission radio de l'activité musculaire en technologie hybride". Grenoble 1, 1987. http://www.theses.fr/1987GRE10083.
Texto completoResumen
Etude electromyographique par telemetrie, permettant d'analyser l'activite de quatre muscles travaillant simultanement chez un veliplanchiste en competition. L'equipement emporte doit etre le plus petit et le plus leger possible
24
Williams, Denise F. y Ralph I. Ebener. "An evaluation and comparison of the Army's acquisition plans for two tactical command control and communications systems: mobile subscriber equipment and single channel ground and airborne radio system". Thesis, Monterey, California. Naval Postgraduate School, 1990. http://hdl.handle.net/10945/30667.
Texto completoResumen
Approved for public release, distribution unlimitedThis thesis evaluates the Acquisition Plans of two US Army Command, Control and Communications (C3) systems: Mobile Subscriber Equipment (MSE) and the Single Channel Ground and Airborne Radio System (SINCGARS), both of which are components of the Army Tactical Command and Control System (ATCCS). The study examines the defense acquisition process through the comparison of the Acquisition Plans and lessons learned for these two programs, and determines if there is an optimal strategy for the Army to use when acquiring tactical C3 systems. An analysis of the strengths and weaknesses of the two Acquisition Plans, and an evaluation of the similarities and differences of two programs, concludes that the MSE Acquisition Plan proved more successful than its SINCGARS counterparts because of its Non-Developmental Item approach. This study recommends maximum use of the NDI strategy for acquiring C3 systems whenever possible
25
Wong, Wing-lun Alan. "The development and competition of the mobile phone industry in Hong Kong /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19872124.
Texto completo
26
Maddali, Hanuma Teja. "Inferring social structure and dominance relationships between rhesus macaques using RFID tracking data". Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51866.
Texto completoResumen
This research address the problem of inferring, through Radio-Frequency Identification (RFID) tracking data, the graph structures underlying social interactions in a group of rhesus macaques (a species of monkey). These social interactions are considered as independent affiliative and dominative components and are characterized by a variety of visual and auditory displays and gestures. Social structure in a group is an important indicator of its members’ relative level of access to resources and has interesting implications for an individual’s health. Automatic inference of the social structure in an animal group enables a number of important capabilities, including:
1. A verifiable measure of how the social structure is affected by an intervention such as a change in the environment, or the introduction of another animal, and
2. A potentially significant reduction in person hours normally used for assessing these changes.
The behaviors of interest in the context of this research are those definable using the macaques’ spatial (x,y,z) position and motion inside an enclosure. Periods of time spent in close proximity with other group members are considered to be events of passive interaction and are used in the calculation of an Affiliation Matrix. This represents the strength of undirected interaction or tie-strength between individual animals. Dominance is a directed relation that is quantified using a heuristic for the detection of withdrawal and displacement behaviors. The results of an analysis based on these approaches for a group of 6 male monkeys that were tracked over a period of 60 days at the Yerkes Primate Research Center are presented in this Thesis.
27
Pache, Denis. "Étude de nouvelles architectures pour l'intégration de fonctions radio fréquence en technologie BiCMOS". Grenoble INPG, 1996. http://www.theses.fr/1996INPG0079.
Texto completoResumen
Ce travail est consacre a l'integration des fonctions radio frequence (rf) de la partie reception d'un terminal mobile 2ghz en technologie silicium bicmos. Dans une premiere partie, les differentes caracteristiques des systemes rf sont rappelees. Ces systemes sont particulierement complexes (architecture, fiabilite) et les problemes lies a leur integration sont mis en evidence. Dans la partie suivante les principes de base et les proprietes des modulations analogiques et numeriques sont donnes. Dans une troisieme partie les composants silicium sont analyses. En particulier, une comparaison entre les transistors bipolaire et mos montre leurs limitations respectives et leur complementarite. Les systemes rf utilisent des inductances ; une modelisation de ce composant passif est proposee pour son integration sur silicium. Dans la derniere partie, quatre architectures pour une integration complete des quatre fonctions principales d'un recepteur (lna, filtre de frequence image et melangeur, filtre de frequence intermediaire, synthetiseur de frequence) sont proposees. Ces architectures ont ete validees par des mesures sur circuit. Leurs performances et leur souplesse permettent d'envisager maintenant la conception d'un recepteur rf totalement integre et adaptable a la plupart des normes des systemes rf (actuels ou futurs)
28
Wu, Xiguang. "Hierarchical reconfiguration management for heterogeneous cognitive radio equipments". Thesis, CentraleSupélec, 2016. http://www.theses.fr/2016SUPL0002/document.
Texto completoResumen
Pour supporter l’évolution constante des standards de communication numérique, du GSM vers la 5G, les équipements de communication doivent continuellement s’adapter. Face à l’utilisation croissante de l’internet, on assiste à une explosion du trafic de données, ce qui augmente la consommation d'énergie des appareils de communication sans fil et conduit donc à un impact significatif sur les émissions mondiales de CO2. De plus en plus de recherches se sont concentrées sur l'efficacité énergétique de la communication sans fil. La radio Intelligente, ou Cognitive Radio (CR), est considérée comme une technologie pertinente pour les communications radio vertes en raison de sa capacité à adapter son comportement à son environnement. Sur la base de métriques fournissant suffisamment d'informations sur l'état de fonctionnement du système, une décision optimale peut être effectuée en vue d'une action de reconfiguration, dans le but de réduire au minimum la dissipation d'énergie tout en ne compromettant pas les performances. Par conséquent, tout équipement intelligent doit disposer d’une architecture de gestion de la reconfiguration. Nous avons retenu l’architecture HDCRAM (Hierarchical and Distributed Cognitive Radio Architecture Management), développée dans notre équipe, et nous l’avons déployée sur des plates-formes hétérogènes. L'un des objectifs est d'améliorer l'efficacité énergétique par la mise en œuvre de l’architecture HDCRAM. Nous l’avons appliquée à un système OFDM simplifié pour illustrer comment HDCRAM permet de gérer efficacement le système et son adaptation à un environnement évolutifAs the digital communication systems evolve from GSM and now toward 5G, the supported standards are also growing. The desired communication equipments are required to support different standards in a single device at the same time. And more and more wireless Internet services have been being provided resulting in the explosive growth in data traffic, which increase the energy consumption of the communication devices thus leads to significant impact on global CO2 emission. More and more researches have focused on the energy efficiency of wireless communication. Cognitive Radio (CR) has been considered as an enabling technology for green radio communications due to its ability to adapt its behavior to the changing environment. In order to efficiently manage the sensing information and the reconfiguration of a cognitive equipment, it is essential, first of all, to gather the necessary metrics so as to provide enough information about the operating condition thus helping decision making. Then, on the basis of the metrics obtained, an optimal decision can be made and is followed by a reconfiguration action, whose aim is to minimize the power dissipation while not compromising on performance. Therefore, a management architecture is necessary to be added into the cognitive equipment acting as a glue to realize the CR capabilities. We introduce a management architecture, namely Hierarchical and Distributed Cognitive Radio Architecture Management (HDCRAM), which has been proposed for CR management by our team. This work focuses on the implementation of HDCRAM on heterogeneous platforms. One of the objectives is to improve the energy efficiency by the management of HDCRAM. And an example of a simplified OFDM system is used to explain how HDCRAM works to efficiently manage the system to adapt to the changing environment
29
Xing, Chengwen y 邢成文. "Linear minimum mean-square-error transceiver design for amplify-and-forward multiple antenna relaying systems". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44769738.
Texto completo
30
Shankar, Arun. "Optimal jammer placement to interdict wireless network services". Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://handle.dtic.mil/100.2/ADA483583.
Texto completoResumen
Thesis (M.S. in Operations Research and M.S. in Applied Mathematics)--Naval Postgraduate School, June 2008.Thesis Advisor(s): Alderson, David ; Zhou, Hong. "June 2008." Description based on title screen as viewed on August 22, 2008. Includes bibliographical references (p. 39-40). Also available in print.
31
Gul, Sufi Tabassum. "Optimization of Multi-standards Software Defined Radio Equipments: A Common Operators Approach". Phd thesis, Université Rennes 1, 2009. http://tel.archives-ouvertes.fr/tel-00446230.
Texto completoResumen
La technique de paramétrisation est très prometteuse pour la conception radio logicielle. La radio logicielle consiste à concevoir des systèmes multi-standards qui tirent bénéfice des possibilités de programmation ou de reconfiguration offertes par les composants de traitement la constituant. Cette thèse étudie la technique de paramétrisation par opérateurs communs. Les opérateurs communs sont des unités de traitements communes à plusieurs opérations qu'effectue un équipement, quelle que soit la couche du modèle OSI à laquelle elles appartiennent. La méthode proposée repose sur une approche théorique afin de résoudre le problème de conception d'un équipement multi-standards. Elle consiste en une optimisation d'un hypergraphe. La conception de l'équipement est représentée par des opérateurs à différents niveaux de granularité dans un graphe acyclique orienté. Le niveau le plus élevé représente une approche de conception d'équipements multi-standards de type Velcro. Plus les opérateurs sont bas dans le graphe, plus leur coût est faible en termes de complexité, mais plus il faut faire appel de fois à eux pour effectuer des opérations de différentes sortes. Nous décrivons ensuite en tant qu'exemples des conception basées sur les opérateurs DMFFT (dual mode FFT), LFSR (linear feedback shift register) et le cas du FRMFB (frequency response masking filter bank). Les solutions basées sur les opérateurs communs proposées dans cette thèse peuvent contribuer à optimiser la conception des futurs équipements multi-standards de radio logicielle qui devront supporter de nombreux standards de communication sans fil.
32
Gul, Sufi Tabassum. "Optimization of multi-standards software defined radio equipments : a common operator's approach". Rennes 1, 2009. http://www.theses.fr/2009REN1S074.
Texto completoResumen
Parameterization is a very promising technique for Software Defined Radio (SDR) that consists of designing multi-standards radio systems entities in a way which permits to take advantages of the programmable or at least reconfigurable capabilities of the underlying hardware of SDR equipments. This thesis addresses the common operators’ (COs) technique for parameterization. COs are processing commonalities between operations of an equipment whatever the Open System Interconnection (OSI) layer may be. The method proposes a theoretical approach to solve the design issue of multi-standards radio equipments. It consists in a hypergraph’s optimization. The equipment design is represented with operators of several levels of granularity in a directed acyclic graph. Top level of this graph represents a Velcro way of designing multi-standards equipments. The lower, the operators in the graph, lower is their cost in terms of complexity but higher is the number of times they are called to perform the operations of different kinds and vice versa. As examples, we describe the design and use of dual mode fast Fourier transform (DMFFT), linear feedback shift register (LFSR) and frequency response masking filter bank (FRMFB) as COs. The proposed solutions in this thesis which are based on CO technique help an SDR designer to optimize the design of future multi-standards SDR equipments that are required to support a wide range of existing and future wireless technologies and servicesLa technique de paramétrisation est très prometteuse pour la conception radio logicielle. La radio logicielle consiste à concevoir des systèmes multi-standards qui tirent bénéfice des possibilités de programmation ou de reconfiguration offertes par les composants de traitement la constituant. Cette thèse étudie la technique de paramétrisation par opérateurs communs. Les opérateurs communs sont des unités de traitements communes à plusieurs opérations qu’effectue un équipement de radio communication, quelle que soit la couche du modèle OSI à laquelle elles appartiennent. La méthode proposée repose sur une approche théorique afin de résoudre le problème de conception d’un équipement multi-standards. Elle consiste en une optimisation d’un hypergraphe. La conception de l’équipement est représentée par des opérateurs à différents niveaux de granularité dans un graphe acyclique orienté. Le niveau le plus élevé représente une approche de conception d’équipements multi-standards de type Velcro. Plus les opérateurs sont bas dans le graphe, plus leur coût est faible en termes de complexité, mais plus il faut faire appel de fois à eux pour effectuer des opérations de différentes sortes. Nous décrivons ensuite en tant qu’exemples des conception basées sur les opérateurs DMFFT (dual mode FFT), LFSR (linear feedback shift register) et le cas du FRMFB (frequency response masking filter bank). Les solutions basées sur les opérateurs communs proposées dans cette thèse contribuent à optimiser la conception des futurs équipements multi-standards de radio logicielle qui devront supporter de nombreux standards de communication sans fil
33
Owen, Alan. "The application of low aspect ratio hydrofoils to the secure positioning of static equipment in tidal streams". Thesis, Robert Gordon University, 2007. http://hdl.handle.net/10059/470.
Texto completoResumen
The costs of installing tidal energy technology are high, requiring expensive vessels to drill sockets in the sea bed or to handle gravity based structures of substantial mass, and this impacts on the commercial viability of any proposed marine renewables development. This thesis offers a viable alternative to socketed or gravity based installations by proposing that the downwards lift force that can be developed from the flow over a hydrofoil can be used to resist the slip and overturning moments applied to a structure by the flow. The fundamental theory of axial and crossflow energy conversion devices is outlined and the current methods of fixing and supporting tidal stream devices are analysed. The origins of tidal stream flows are discussed and the effects of local topography, bathymetry and system resonance are used to explain the significant differences between real tidal behaviour and the ideal of Newton’s equilibrium theory. The idiosyncratic and localised nature of tidal streams is thereby made clear as well as the need for a solid understanding of the resource prior to device design and installation. The principles of classical hydrodynamics and conformal mapping are used in the context of relating theoretical lift and drag functions to low aspect ratio hydrofoils with endplates, and a numerical model of distributed surface pressures around a hydrofoil is demonstrated. Subsequently, the concept is evaluated using two 1/7th scale test devices, one is field tested in a large stream under real flow conditions, and the second in a tow tank under ideal laboratory conditions. The limitations and challenges of model scaling are shown and the semi-empirical Froude method of scaling using residual forces is applied to the towing model. Analysis of the experimental data shows a correlation with normal distribution and extrapolation of the experimental results shows that the Sea Snail can operate with an average lift coefficient of 0.7 and drag coefficient of 0.18. Application of the experimental data to the full scale device demonstrates that the Sea Snail principle is not only valid, but is a significant advance on existing installation methodologies.
34
Afzal, Humaira. "Modelling and analysis of dynamic spectrum sharing in cognitive radio based wireless regional area networks : modelling and performance evaluation of initialization and network association of customer premise equipments with the base station in cognitive radio based IEEE 802.22 wireless regional area networks". Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7317.
Texto completoResumen
The development of the IEEE 802.22 standard is aimed at providing broadband access in rural areas by effectively utilizing the unused TV band, provided no harmful interference is caused to the incumbent operation. This thesis presents the analytical framework to evaluate the number of active customer premise equipments (CPEs) in a wireless regional area network. Initial ranging is the primary process in IEEE 802.22 networks for CPEs to access the network and establish their connections with the base station (BS). A comprehensive analysis of initial ranging mechanism is provided in this work and initial ranging request success probability is derived based on the number of contended CPEs and the initial contention window size. Further, the average ranging success delay is derived for the maximum backoff stages. The collision probability is highly dependent on the size of the initial contention window and the number of contended CPEs. To keep it at a specific level, it is necessary for the BS to schedule the required size of the initial contention window to facilitate the maximum number of CPEs to establish their connections with reasonable delay. Therefore, the optimized initial window size is proposed that meets the collision probability constraint for a particular number of contended CPEs. An analytical model is also developed to estimate the ranging request collision probability depending upon the size of initial contention window and the number of contended CPEs. Moreover, this approximation provides the threshold size for contention window to start the initial ranging process in the IEEE 802.22 network.
35
Chou, Chi-Wu Information Technology & Electrical Engineering Australian Defence Force Academy UNSW. "Evolutionary cluster costing for weapon system early design". Awarded by:University of New South Wales - Australian Defence Force Academy. School of Information Technology and Electrical Engineering, 2004. http://handle.unsw.edu.au/1959.4/38648.
Texto completoResumen
The Evolutionary Cluster Costing Methodology (ECCM) is proposed for estimating the cost of designing and producing a weapon system at the early design stage. The issue is related to the particular difficulties which system designers often encounter in the absence of cost data on present system details and historically relevant cases associated with the early development phase of a major acquisition project. This is especially relevant in the military environment. In general, the traditional approach for new system cost estimation is to use parametric methods with data from a number of historical cases. However, when there are limited cases it is difficult to establish appropriate and reliable cost models. As an approach to solving this problem, this research has developed ECCM to generate cost characteristics from only a few or even a single existing case to estimate new system costs. The purpose of ECCM is to extract cost characteristics from an existing system by separating it into mutually independent function clusters. Accordingly, ECCM consists of three essentials: function activity cost tables (FACT), an evolutionary clustering methodology, and cost pattern usages. Based on value engineering and system engineering, a system is made up of a particular group of functions, and each function is further supported by certain activities. Because activities can be represented as resources used for supporting related functions, cost employment among functions can be allocated as FACT. As part of the process, a binary incident matrix is constructed, where the values 1 or 0 represent the existence or non-existence of cost interactions between activity and function in FACT. The binary matrix can easily be deduced to represent the most relevant function clusters. To solve the N-P complete combinatorial problem, evolutionary algorithms and proposed cluster evaluation formulae are integrated into the evolutionary clustering methodology. Once the optimal function clusters have been grouped, the costs that interact among functions and activities can be relisted and rated into ratios within each cluster. Cost patterns can then be determined by activity cost ratios from individual clusters. The cost of a new system can be evaluated by considering each similar cluster as a cost parameter because each cluster represents the cost characteristics of a particular function group. Based on the fact that the technology is evolving gradually and the functions in a cluster are related to each other through certain resource relationships, the cost of new systems or products can be estimated by using those clusters. The cost estimates for the new system are obtained through comparing the needs of technologies or values in similar function clusters of existing systems. A case study from three generations of light-sport helicopters has shown that function and assembly clusters can be used to infer the cost of a new design. The results from the case study demonstrate that: 1) the various functions can be clustered to create a certain number of critical purposes, e.g., engine power or structural strength and safety related tasks; 2) ECCM can be used to estimate empirical costs given the absence of detailed design information; 3) the function and assembly similarities of clusters among systems are statistically significant; 4) the differences of cost ratios in related clusters between systems are not statistically significant; 5) the differences between cluster's estimated costs and actual costs in helicopter L-2 or L-3 are not significant statistically; and 6) the differences between assembly's estimated costs and actual costs in L-2 or L-3 are not significant statistically. The cost ratio patterns of individual clusters can be used to target the activity or assembly budgets for developing new systems.
36
Leite, Rafael Valadares. "Desenvolvimento de um espectrômetro nuclear digital de radiação gama". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3139/tde-08032007-175805/.
Texto completoResumen
O método nuclear gamaespectrométrico vem ganhando espaço em diversas aplicações como fornecer a informação médica em um paciente ou de uma galáxia distante, detectar radioatividade para fins de segurança e medir a concentração de radioelementos em um mineral ou rocha. Esta dissertação apresenta um projeto e implementação de um espectrômetro gama digital conectado a um conjunto detector contendo cristal cintilador de iodeto de sódio dopado com tálio. O hardware é baseado em um dispositivo lógico programável da família CoolRunner II da Xilinx e um conversor analógico-digital de 80 MHz da Analog Devices. A aquisição de dados é executada em um computador pessoal comum. As linguagens de programação utilizadas foram VHDL e C#. O objetivo desta dissertação é apresentar todas as etapas necessárias para o desenvolvimento de um gamaespectrômetro digital e inclui pesquisa bibliográfica, estudo do equipamento, modelagem dos cristais, simulação do projeto de um gamaespectrômetro, montagem do circuito eletrônico, desenvolvimento do processamento e lógica do circuito, criação do software de aquisição dos dados em tempo real e apresentação dos resultados obtidos.The gammaspectrometric method has been used for diverse applications as to supply the medical information in a patient or a distant galaxy, to detect radioactivity at airport and to measure the concentration of radioelements in a mineral or rock. This work presents a digital gammaspectrometer project and implementation for acquisition of radiometric data, the spectrometer is connected to a gamma-ray detector NaI(Tl). The two main components in hardware are complex programmable logical device of the family CoolRunner II Xilinx and an 80 MHz analog to digital converter of brand Analog Devices. The acquisition of data is executed in a common personal computer. The programming languages used are VHDL and C#. The objective of this work is to present all the needful stages for the digital gammaspectrometry development that includes theorem, equipment studying, crystal modeling, gammaspectrometry modeling and simulation, electronic circuit assembly, processing and logic circuit development, data acquisition software in real time development and presentation of results.
37
Neto, Annibal Theotonio Baptista. "Implantação de radiações de referência em máquina de raios X diagnóstico médico para fins de calibração de dosímetros pessoais". CNEN - Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, 2005. http://www.bdtd.cdtn.br//tde_busca/arquivo.php?codArquivo=39.
Texto completoResumen
NenhumaCampos de raios-x que estejam em conformidade com os requisitos internacionais de padronização nem sempre são disponíveis em uma região e, principalmente, em países em desenvolvimento. Esta situação tem sido usada como justificativa para a ausência de calibração de dosímetros pessoais e tem contribuído para a falta de confiabilidade nos programas de monitoração de trabalhadores expostos à radiação. Considerando a existência de diversas máquinas de raios-x em hospitais e a necessidade da calibração de dosímetros pessoais, este trabalho investigou a viabilidade da implantação de feixes de radiação-x destinados à calibração, comparáveis às radiações padronizadas internacionalmente, em uma máquina de raios-x diagnóstico médico. A implantação das radiações para calibração foi realizada com a determinação e comparação de parâmetros dos feixes de raios-x como a tensão do tubo, camada semi-redutora, uniformidade do campo de radiação, filtração e radiação espalhada. Os procedimentos, a geometria e as condições de irradiação foram, sempre, os mais simples possíveis para uma confiabilidade mínima dos resultados, nas condições usuais em hospitais. A viabilidade do uso dos feixes de radiação implantados foi confirmado através da análise do desempenho de um dosímetro pessoal do tipo filme, em calibrações e irradiações no Laboratório de Calibração de Dosímetros do Centro de Desenvolvimento da Tecnologia Nuclear, no Laboratório Nacional de Metrologia das Radiações Ionizantes e no University of Wisconsin Radiation Calibration Laboratory. Apesar da diferença entre os feixes de raios-x implantados e as radiações de referência, o desempenho do dosímetro pessoal atendeu aos requisitos para a monitoração individual.
X-ray fields that comply with international standardization requirements are not available in a world region, mainly in developing countries. This is used as an excuse for a lack of calibration of personal dosimeters and, consequently, a lack of reliability in individual monitoring programs applied to occupational workers under radiation exposures. Considering the availability of x-ray machines in many hospitals, this work studied the feasibility of implementing x-ray calibration beams in a medical diagnostic machine, which are comparable to international reference radiations for calibrating personal dosimeters. Implementation of the calibration beams was carried out by determining and comparing beam parameters as tube voltage, half-value layer, beam uniformity, filtration and scattered radiation. Procedures, geometry and exposure conditions were as simple as possible for a minimum reliability and close to the hospital conditions. The feasibility of the use of the implemented radiation beams was confirmed by analyzing the performance of a film personal dosimeter under calibration and irradiation at the Dosimeter Calibration Laboratory of the Centro de Desenvolvimento da Tecnologia Nuclear, the National Metrology Laboratory for Ionizing Radiations and the University of Wisconsin Radiation Calibration Laboratory. In spite of the difference between the implemented x-ray beams and the reference radiations, the performance of the film personal dosimeter complied with the accuracy requirements for individual monitoring.
38
Debebe, Senait Aknaw. "Quantitative Yttrium-90 Bremsstrahlung SPECT/CT and PET/CT Study for 3D Dosimetry in Radiomicrosphere Therapy". FIU Digital Commons, 2017. https://digitalcommons.fiu.edu/etd/3538.
Texto completoResumen
Liver cancer ranks the third most common cause of cancer related mortality worldwide. Radiomicrosphere therapy (RMT), a form of radiation therapy, involves administration of Yttrium-90 (90Y) microspheres to the liver via the hepatic artery. 90Y microspheres bremsstrahlung SPECT/CT or PET/CT imaging could potentially identify an extrahepatic uptake. An early detection of such an uptake, thus, could initiate preventative measures early on. However, the quantitative accuracy of bremsstrahlung SPECT/CT images is limited by the wide and continuous energy spectrum of 90Y bremsstrahlung photons. 90Y PET/CT imaging is also possible but limited by the extremely small internal pair production decay. These limitation lead to inaccurate quantitation of microsphere biodistribution especially in small tumors.
SPECT/CT and PET/CT acquisition of a Jasczak phantom with eight spherical inserts filled with 90Y3Cl solution were performed to measure the quantitative accuracy of the two imaging modalities. 90Y microsphere SPECT/CT data of 17 patients who underwent RMT for primary or metastatic liver cancer were acquired. Technetium-99m macroaggregated albumin (99mTc-MAA) SPECT/CT scans were also collected, but available for only twelve of the patients. SPECT/CT images from phantoms were used to determine the optimal iteration number for the iterative spatial resolution recovery algorithm. Methods for image based calculation of calibration factors for activity estimation from the patient and phantom 90Y bremsstrahlung SPECT/CT images were developed. Tumor areas were segmented using an active contour method. The 99mTc-MAA and 90Y microsphere SPECT/CT images were co-registered a priori for correlation analysis. Comparison of uptake on 99mTc-MAA and 90Y microsphere SPECT/CT images was assessed using tumor to healthy liver ratios. Furthermore, a three dimensional absorbed dose estimation algorithm was developed using the voxel S-value method. Absorbed doses within the tumor and healthy part of the liver were investigated for correlation with administered activity.
Improvement in contrast to noise ratio and contrast recovery coefficients (QH) on patient and phantom 90Y bremsstrahlung SPECT/CT images as well as PET/CT images were achieved. Total activity estimations in liver and phantom gave mean percent errors of -4 ± 12% and -23 ± 41% for patient and phantom SPECT/CT studies. The pre and post-treatment images showed significant correlation (r = 0.9, p < 0.05) with mean TLR of 9.2 ± 9.4 and 5.0 ± 2.2 on 99mTc-MAA and 90Y microspheres SPECT/CT respectively. The correlation between the administered activity and tumor absorbed dose was weak (r = 0.5, p > 0.05), however, healthy liver absorbed dose increased with administered activity (r = 0.8, p < 0.05).
39
Миндюк, В. Д. "Розроблення методу оцінки якісних змін матеріалів нафтогазового обладнання за комплексом фізичних характеристик". Thesis, Івано-Франківський національний технічний університет нафти і газу, 2014. http://elar.nung.edu.ua/handle/123456789/4680.
Texto completoResumen
Досліджено особливості мікроструктурих змін матеріалів металоконструкцій в процесі експлуатації. Встановлено основні фізичні параметри, що зазнають змін внаслідок змін в мікроструктурі. Проаналізовано сучасний стан методів та засобів проведення структуроскопії. Проведено дослідження якісних змін фізичних параметрів матеріалів в залежності від зміни мікроструктури. Проведено дослідження щодо для одержання основних параметрів мікроструктури з використанням нових методів обробки металографічних зображень, а також фізичних характеристик матеріалу з використанням методів і засобів, що грунтуються на різних фізичних принципах. Встановлений оптимальний комплекс фізичних параметрів, що найкраще корелюють з вибраними параметрами мікроструктури. З використанням алгоритмів штучних нейронних мереж одержані функції апроксимації параметрів мікроструктури, а саме співвідношення перліт/ферит та середній діаметр зірна, від твердості, коерцитивної сили та магнітного індукційного параметру, що характеризує частоту електромагнітних коливань індуктивного перетворювача. Розроблено методологію оцінювання якості матеріалу шляхом визначення параметрів мікроструктури за комплексом фізичних характеристик для подальшого їх використання для розрахунків механічних характеристик матеріалів та оцінювання ступеню деградації матеріалу.Диссертация посвящена вопросу оценки качества материалов нефтегазового оборудования путем оценки микроструктурных изменений за комплексом физических характеристик. Анализ процессов деградации структуры разных типов сталей и ее последствий показал, что показателями деградации структуры металла, которые стоит поддавать диагностике, есть изменение размеров и ориентации зерен отдельных структурных фаз со временем, морфологическое изменение отдельных фаз и изменение их соотношения в структуре, что значительно влияют на изменение отдельных физических свойств материалов, а, особенно, - структурно чувствительных параметров, выделение вторичных фазовых составляющих (например, карбидов легирующих элементов или низкотемпературных модификаций металла из высокотемпературной) из основных фаз и распределение их по границах зерен, группирования в отдельные зоны. Во втором разделе проведено качественное изучение процессов изменения физических структуруо чувствительных свойств ферритных сталей. На основе результатов изучения особенностей изменения магнитных свойств, электрического сопротивления, теплопроводной характеристику и твердости, избранные параметры выбраны для дальнейших исследований относительно определения корреляции между этими параметрами и параметрами микроструктуры. Третий раздел содержит методику и результаты экспериментальных исследований по установлению зависимости избранных информативных физических параметров от параметров микроструктуры отобранных образцов разных марок сталей. Определены зависимости отдельных физических свойств сплавов от характеристик микроструктуры - соотношения перлит/феррит и среднего диаметра зерна, а также определен оптимальный комплекс физических свойств с наилучшей корреляцией их с параметрами микроструктуры. Использование алгоритмов нейронных сетей позволило получить зависимости микроструктурных характеристик от комплекса физических свойств в аналитическом виде. Четвертый раздел посвящен разработке методологии оценки качества материала путем определения параметров микроструктуры за комплексом физических характеристик для дальнейшего их использования для расчетов механических характеристик материалов и оценки степени деградации материала, которая прошла успешную промышленную апробацию в условиях РВУ «Львовавтогаз» и НПФ «Зонд» и внедрена в нормативных документах нефтегазовой отрасли.
Dissertation is devoted to assessing the quality of oil and gas equipment materials by evaluating complex microstructural changes with physical characteristics. The features of the microstructural changes of metal materials during operation are investigated. The basic physical properties that are experiencing changes due to changes in the microstructure are identified. The current state of methods and means of structurescopy are analized. The investigation of qualitative changes in the physical parameters of materials depending on the change of the microstructure are studied. The main parameters of the microstructure with using new methods of metallographic image processing were obtained, as well as the physical characteristics of the material using the methods and tools that are based on different physical principles were measured. The optimal set of physical parameters that best correlated with the selected parameters of the microstructure is established. Approximation functions of microstructure parameters such as a ratio of pearlite/ferrite and the average grain diameter with the hardness, coercitiviy, magnetic induction parameter which characterizes the oscillation frequency of the electromagnetic inductive transducer are obtained by using artificial neural networks algorithm. A methodology for assessing the quality of the material by determining the microstructure parameters with the complex of physical characteristics for further use in the calculation of materials mechanical characteristics and material degradation assessment is developed.
40
Посунько, Людмила Миколаївна, Людмила Николпевна Посунько y L. Posunko. "Обґрунтування параметрів транспортно-технологічних схем проведення дільничних виробок при розширенні меж шахтних полів". Thesis, Видавництво НГУ, 2010. http://ir.nmu.org.ua/handle/123456789/84.
Texto completoResumen
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.15.02 – «Підземна розробка родовищ корисних копалин». Національний гірничий університет Міністерства освіти і науки України, Дніпропетровськ, 2010.Диссертация на соискание научной степени кандидата технических наук по специальности 05.15.02 - «Подземная разработка месторождений полезных ископаемых». Национальный горный университет Министерства образования и науки Украины, Днепропетровск, 2010.
The thesis for the degree of candidate of technical sciences, specialty 05.15.02 - "Underground Mining". National Mining University, Ministry of Education and Science of Ukraine, Kiev, 2010.
Дисертація присвячена обґрунтуванню параметрів енергозберігаючих транспортно-технологічних схем проведення дільничних виробок при розширенні меж шахтних полів. Вперше обґрунтована доцільність введення в діючі методики розрахунків темпів комбайнового проведення дільничних виробок коефіцієнта адаптації транспортно-технологічної системи, який синтезує технічні ресурси гірничопрохідницького і транспортного устаткування нового покоління з використанням надґрунтових канатних доріг як єдиного транспортного засобу в протяжних виробках, криволінійних в профілі і плані. В дисертації запропоновані і науково обґрунтовані параметри організації робіт, що дозволяють підвищити темпи проведення підготовчих виробок шляхом синхронізації витрат часу на виконання процесів кріплення і транспортування. На основі отриманих результатів запропонована методика вибору оптимальних параметрів енергозберігаючої транспортно-технологічної системи комбайнового проведення дільничних виробок при розширенні меж шахтних полів. Річний економічний ефект від впровадження рекомендацій складає 376 тис. грн.
Диссертация посвящена обоснованию параметров энергосберегающих транспортно-технологических схем проведения участковых выработок при расширении границ шахтных полей. Технология комбайнового проведения выработок с применением проходческого и транспортного оборудования нового поколения впервые рассматривается как транспортно-технологическая система. Разработана модель повышения темпов комбайнового проведения выработок путем координации эксплуатационных параметров технологи-ческого и транспортного оборудования нового поколения, рекомендуемого для подготовки резервных запасов угля, расположенных в зонах влияния тектонических нарушений, с целью расширения границ шахтных полей и срока действия угольных предприятий. Впервые обоснована целесообразность введения в действующие методики расчетов темпов проведения участковых выработок, коэффициента адаптации транспортно-технологической системы, который устанавливает взаимосвязь между эксплуатационными параметрами проходческих комбайнов нового поколения и сроком оборачиваемости вагонеток при использовании напочвенных канатных дорог как единого транспортного средства в протяженных выработках, искривленных в профиле и плане. В диссертации представлены результаты экспериментальных исследований взаимодействия элементов транспортно-технологической системы, разработаны схемы адаптации транспортного оборудования в сложных условиях подготовки резервных запасов угля, прирезаемых дополнительно. Разработана методика обоснования параметров и схем организации комбайнового проведения подготовительных горных выработок, которая позволяет повысить темпы и снизить трудоемкость горнопроходческих работ при доработке запасов угля у границ шахтных полей и разработке засбросовых частей шахтного поля. На основе полученных результатов спроектированы технологические схемы комбайнового проведения подготовительных выработок с использованием напочвенных канатных дорог нового поколения для сложных горно-геологических условий Западного Донбасса. Результаты промышленных испытаний экспериментального образца напочвенной канатной дороги ДКНП-1,6 длиной 3360м позволили установить ее эксплуатационные параметры и область эффективного применения. При сокращении срока подготовки выемочных столбов с 10,2 до 7,6 месяцев за счет использования транспортно-технологических схем нового поколения и рациональной организации работ в участковых подготовительных выработках годовой экономический эффект составляет 376 тис. грн.
The thesis is devoted to the parameters of transport and technological schemes of the district workings while expanding the borders of the mine fields. Technology Combine for roadway with a tunnel and transport equipment of new generation for is considered as transport-technological system firstly. The developed model allows us to establish the relationship between technological transport processes Combine workings during the preparation of a reserve stock of coal, adding on to the existing mine fields (located in the zones of influence of geological disturbances). Firstly the expediency of application the method of calculation of the rate of district workings of the ratio adaptation of transport-technological system, which establishes the relationship between the operational parameters of tunnel combines of a new generation and the turnaround term using the Soil cableways as a single vehicle in the extended workings, curved in profile and plan. Based on the obtained results are designed for complex mining and geological conditions of the Western Donbass, flow charts Combine the preparatory workings, using Soil lifts of a new generation. Methodical recommendations on the establishment the rate of turnover trucks to transport goods in extended workings, curved in profile and plan, the choice of rational parameters of rock mass storage and organization of the exchange-transport operations. Expected annual economic effect of implementing the recommendations – 376 thousands uah.
41
Šimeček, Ondřej. "Problematika šablonového tisku pájecí pasty pro součástky s malou roztečí vývodů". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218992.
Texto completoResumen
Despote the indisputable advantages of fine-pitch components, is need to calculate with a few trouble during production, especially increased requirements for accuracy of mounting and solder printing. In this work I’m concerned with problems of solder printing for these components and evaluation using SPC. For the evaluation I used 3D paste inspection based on laser scanning of the surface. The output of this work is to describe the principles of solder printing and elaborating of GR&R, SPC analysis and histograms of solder printing for some outputs. I focused in my master thesis on motive design change of problematic components and economic evaluation of the adjustments.
42
Wang, Chen Feng y 王辰丰. "The Regulatory Reform of The Power Radio Frequency Equipment". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/66906982481507644771.
Texto completoResumen
碩士國立清華大學
科技法律研究所
104
The subject of this thesis is “The Regulatory Reform of The Low Power Radio Frequency Equipment” and the purpose of the study was to research whether the existing regulatory was necessary to be amended. With the realization of the concept of IOT （Internet of Things）, there will be various kinds of radio frequency equipment in human life. At the present stage, there still exist the problems of interference. Our government still regulate radio frequency equipment with radio technology before it enters the market which is based on the order of electric waves, national security, etc. However, there are many scholars think some of low-risk products should be deregulated. According to the categories of equipment, the government legislates five regulations which is based on the concept of Telecommunications Act. Those regulations comply with technical regulations and the conformity assessment under the framework of the WTO TBT Agreement. It causes the non-tariff barriers to international trade. Member states of the WTO should comply with the GATT for non-discrimination and the related regulations under article 2 of the TBT agreement to implement the spirit of freedom and fair trade. In recent years, the dispute cases of the low power radio frequency equipment occurred often in Taiwan. How to revise the regulations and supervise the execution of them have given more attention to the world. Although there are many different regulations among nations, we can see that developed countries such as European Union, America, and Japan have revised their regulations to enhance international economic development and react the rapid evolution of technology. This article represents that our country should review the existing regulations and conformity assessment, establish a clear regulatory classification, after market surveillance system to protect free trade and avoid regulation failure.
43
CHEN, JHIH-HAO y 陳志豪. "Research on Battery Life Prediction System of Radio Communication Equipment". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6rdt2p.
Texto completoResumen
碩士國立高雄科技大學
電子工程系
107
The artificial neural networks (ANN) can solve many complex problems that could not be solved in the past. Since batteries are the most important power modules in radio communication equipment. The battery life prediction can prevent battery failure or improve equipment availability. This thesis adopts a multi-layer perceptron (MLP) and convolutional neural network (CNN) to establish a battery voltage decay model to predict battery life. In this thesis, three data input methods are proposed for three batteries to predict the life. The first data input method is used on the battery with nonlinear attenuation, which will face the problem of large misalignment. The second method is applied the latest four actual data. The predictions can be achieved good accuracy. However, the prediction results cannot fully predict the trend. The third method implemented the latest four data in the past to make future predictions with the previous forecast data and obtain the highest correlation among the methods. The MLP was used in three batteries and compared with the training model of CNN. The result is shown that CNN achieved higher accuracy than MLP.
44
LIN, WEI-MIN y 林威民. "The Research and Analysis of Semiconductor Equipment 13.56MHz Radio Frequency Generator". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/yx7gus.
Texto completoResumen
碩士中華大學
電機工程學系碩士班
103
ABSTRUT The 13.56 MHz 2KW RF Generator play an important role in the semiconductors equipment, including Chemical Vapor Deposition (CVD). This thesis consists of the three parts, a, 13.56MHz 2KW RF Generator of CVD structure. Second, each of the Generator Module uses internal functions. Three, 13.56MHz 2KW RF Generator internal Power Amplifier, Combiner and Matching detailed circuit. We show that how to enhance the ability to repair 13.56MHz 2KW RF Generator proposed effective method. 13.56MHz 2KW RF Generator usually be used in the semiconductor manufacturing equipment. To study the RF generator have increased significantly in the past ten years. This thesis is based on RF principles as the theoretical basis, and learn it in the CVD system, the use of network analyzer measurements Combiner and Matching Analysis 13.56MHz 2KW RF Generator, and use ADS (Advanced Design System) software be Numerical Simulation. Therefore, the study 13.56MHz 2KW RF Generator helpful not only for theoretical research, more specifically, the study showed a high degree of practical effectiveness in the market. Key words: RF Generator、Chemical Vapor Deposition (CVD)、semiconductor、Power Amplifier
45
Hung, Ching Chu y 洪慶助. "Construction Of An Equipment-Auditing Management System Based On Wireless Radio Technology". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/70212254329068997249.
Texto completoResumen
碩士亞洲大學
光電與通訊學系碩士在職專班
100
Today, how to raise the efficiency of fabrication, reduce the price of product and enhance the quality of service are quite critical issues and targets for many departments. To achieve these attractive goals, governmental offices, industrial corporations and academic institutions have proposed various approaches to conquer problems incurred from those objectives mentioned above. One of the effective methods to overcome difficulties of these issues might be information/data digitized. However, to realize such desirable features comes at higher cost, such as more investment of equipment purchase and more mechanics of equipment maintenance. A possible and effective means to relieve those problems is the application of wireless radio frequency technology. Radio frequency identification (RFID) is attracting an ever-increasing interest and plays key role today for its potentiality of data processing at short notice for which it is very momentous for quick data acquisition in wireless technology. The purpose of this study is to construct a system that is used for property auditing and management. The implemental structure of the proposed system is built by association of a RFID with personal digital assistance (PDA) and SQL data base to form a high efficiency, more convenient and promising management system for equipment auditing and management Keywords: Radio frequency identification (RFID), wireless technology, personal digital assistance (PDA), information/data digitized.
46
Ku, Tien-Yu y 古典諭. "Feature Extraction of Radio Frequency Signal for Fault Detection of Plasma Etching Equipment". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/85022142379717843193.
Texto completoResumen
碩士中原大學
機械工程研究所
96
Etch process is an important and indispensable process in the semiconductor manufacturing for removing the pattern defined by photolithography process. Most etched profiles cannot be reworked. Thus, the accuracy of critical dimension, etch depth and etch uniformity depends on the stringently control of etch equipment. However, every mechanism has a chance to decline or damage. Fault detection becomes an important subject in the semiconductor manufacturing. Self organizing feature map network is an artificial neural network with unsupervising competition learning. Input data will be mapped to the output units by self organizing and, finally, assigned in the output space with meaningful topological structure by output neurons according to input data’s vector characteristics. Thus, self organizing feature map network transfers higher dimensional input data to lower dimensional spacial figures. In this thesis, the self organizing feature map network was used for fault detection of radio frequency (RF) power of etch equipment. The waveform of RF power is monitored by self organizing feature map network to prevent faulty process so as to reduce the cost loss in the semiconductor manufacturing. The first step of experiments was to collect 10 sets of normal signals of RF power for offline training. Through the self organizing feature map network, an ellipse was calculated to cover all outputs of neural network and defined as threshold limit. Then, this trained result was implemented to fault detection of etch equipment. A total of 400 waveforms of RF power, i.e. 400 runs of etch processes, were monitored. Among them, 6 abnormal waveform signals were detected and classified into 5 kinds of faults of RF system. The results show that this proposed approach of fault detection has excellent performance.
47
Shi, Zhen-Liang. "Acquisition techniques for direct sequence spread spectrum packet radio systems". Thesis, 1993. https://dspace.library.uvic.ca//handle/1828/9661.
Texto completoResumen
The thesis focuses on fast acquisition techniques for spread spectrum packet radio communications systems. Matched filters are often used to achieve fast acquisitions. A new synchronizer using multiple acquisition detection is designed to achieve a highly reliable synchronization with a very simple receiver structure. Since PN codes, in practice, cannot be made too long due to the difficulty of manufacturing long matched filters and the limitation on the bandwidth of the frequency spectrum for the system, the reliable synchronization can be only obtained by repeating the transmission of the acquisition code at the beginning of each packet. The verification or coincidence detection is done by means of a marker detection following an acquisition. A hard-limiting synchronizer is also examined combined with the multiple acquisition detection. The hard-limiting synchronizer is simpler to implement and suitable for receiving signals with a large SNR dynamic range, but it cannot work well when multi-user interference and multi-path interference are present. For this reason, a new linear Automatic Threshold Control (ATC) synchronizer is developed for detecting signals with a large amplitude dynamic range while preserving good performance in multi-path and multi-user interference. The idea of the ATC scheme is to adjust the receiver acquisition threshold level according to the SNR of the received signal such that the largest (or the most likely) correlation peak in a short time period is selected for the synchronization alignment. Therefore false acquisitions caused by strong correlation side-lobes during the acquisition can be eliminated. For the more realistic situation where the multi-user interference or near-far effect causes severe performance degradation, we proposed a novel non-linear multi-user detector or multistage detector which is suitable for both the synchronous and asynchronous CDMA systems. This sub-optimal detector is able to achieve the performance of the optimal detector with very small computation complexity. The near-far effect will no longer exist because the interference from the unexpected users is considered to be not always harmful for the detection of a specific users' message. To apply this detection technique to asynchronous CDMA systems, acquisition for each users' PN codes becomes more critical, because during the acquisition, the information from the other users' PN code is usually not available, which means that acquisition still suffers the near-far effect. The proposed acquisition scheme based on interference cancellation technique and the ATC scheme can alleviate the near-far effect significantly, and provide the necessary condition for the appropriate operations of multi-user detectors.Graduate
48
Wadley, T. L. "Heterodyne techniques in specialised radio instrumentation". Thesis, 2015. http://hdl.handle.net/10539/18064.
Texto completo
49
chiu, Wen-Chih y 邱文志. "The modeling and controller design of radio frequency impedance matching network in PECVD equipment". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/15721033415570589536.
Texto completoResumen
碩士國立交通大學
機械工程系所
94
In semiconductor processing, the Radio Frequency (RF) power source is used to create plasma for wafer fabrication. Power transmission plays a very important role in wafer processing. Unstable power transmission will lead to unstable plasma, and wafer processing can not achieve it's goal. The impedance matching network behaves like a bridge for power transmission. It reduces the reflective power from the chamber, and increases the transmission power into the chamber, and provides a stable operating power. In this thesis, we use an impedance matching network in a plasma enhanced chemical vapor deposition (PECVD) equipment. First, we use neural network approach to establish the impedance model of the matching network, and the result will be compared with the traditional method to explain its elegance in dealing with stray impedance. Next, we analyze the relationship of input/output signals of RF sensor board in the matching network, and create mathematical model accordingly. Finally, we apply Neuro-Sliding mode control theory to control impedance matching network, and compare its result with the existing controller. The performance of new controller design will be discussed, and the importance of RF sensor signal processing to the control of impedance matching network will be high lighted in the conclusion portion of this research.
50
Hussain, Intikhab. "Channel modelling and analysis of Wits mock-mine with different antenna parameters". Thesis, 2017. http://hdl.handle.net/10539/23519.
Texto completoResumen
A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering, 2017In the mining industry, communications systems are important for ensuring personnel safety and optimizing the mining processes underground. Achieving robust and reliable through-the-air (TTA) communication systems has always been a challenge in the underground mining environment due to harsh and dynamic conditions. TTA requires radio channel characterization for efficient designing and deploying of the communications systems. The literature covers the statistical radio propagation of a room and pillar coal mine, a longwall coal mine, CANMET Gold mine, Camborne School of Mines hard rock mine tunnel, MUZ Coal mine, an iron-ore mine and a lead-zinc mine with linearly polarized antennas at different frequencies. [Abbreviated Abstract. Open document to view full version]
MT 2017