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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Board interconnect testing in a boundary scan environment

McBean, David P. O. January 1993 (has links)
No description available.
2

Influence of contamination on the long-term reliability of chip-on-board (COB) technology

Suthiwongsunthorn, Nathapong January 2002 (has links)
No description available.
3

Specialist F.E. algorithms for dynamic analysis of P.C.B.'s simulating variable edge constraints and localised component stiffness

Battoo, R. S. January 1988 (has links)
No description available.
4

Design and development of the hardware for an automated PCBA inspection and rework cell

Geren, Necdet January 1993 (has links)
No description available.
5

The effect of diffusion layer on throwing power

Hamshow, M. H. January 1986 (has links)
No description available.
6

Model and Analysis of Transmission Lines on Flexible Printed Circuit for the Video Driver Circuit

Huang, Ming-chieh 02 August 2010 (has links)
With smaller electronic devices and higher transmission speeds, a digital circuit will cause potential electromagnetic interference (EMI) and signal integrity (SI) problems. Nowadays, the flexible printed circuit board (FPC) is widely used in electronic systems, especially in the video circuit. In this thesis, we used transmission line model to explain effect of the structure of the flexible printed circuit board transmission lines. Eye-diagram is a fast and convenient tool to analyze the quality of the high speed transmission, and we can use the equivalent model to substitute for the electromagnetic (EM) model to simulate the performance. We used differential circuit and the reflection gain to increase the height and width parameters of Eye-diagram, and make the quality of signal transmission higher. For video driver circuit, since the terminal resistance is different depending on whether the IC is on or off, the standard probe cannot measure mixed-mode S-parameter directly due to the connectors. Thus, we provided a de-embedding method to remove the effects of high speed interconnect line on the test board. Finally, we use a simple structure to verify the method, and it can be used to measure mixed-mode S-parameter on the standard of Mobile Industry Processor Interface (MIPI) for D-PHY, v0.90.00.
7

Ground Antennas for Slim Handsets

CHU, FANG-HSIEN 20 August 2012 (has links)
In this dissertation, multiband ground antennas for slim handsets are presented. The design techniques are on efficiently exciting the resonant modes of the system ground plane of the handset to greatly enhance the antenna¡¦s operating bandwidth. The first antenna design is a monopole antenna integrated with a slot antenna formed in a clearance in the system ground plane to enhance the bandwidth of the antenna¡¦s lower band for penta-band WWAN operation. The second antenna design uses a shaped circuit board with a proper notch embedded therein to result in stronger surface current excitation in the ground plane, which leads to bandwidth enhancement in the antenna¡¦s lower band and upper band. The second antenna design can cover seven-band WWAN/LTE operation. The antenna geometry in the second antenna design is further applied in the third antenna design. In order to meet the practical application of slim handsets, the third antenna design is integrated with a battery element and a metal midplate to decrease the thickness of the handset. The third antenna design can cover seven-band WWAN/LTE operation. Finally, the simulated SAR and HAC results are analyzed for the three proposed antennas.
8

Recuperação de metais a partir do processamento mecânico e hidrometalúrgico de placas de circuito impresso de celulares obsoletos. / Metals recovery from mechanical and hydrometalurgy processing of printed circuit boards from obsolete mobile.

Moraes, Viviane Tavares de 22 December 2010 (has links)
O avanço da tecnologia de aparelhos eletro-eletrônicos favorece a troca constante dos equipamentos. O freqüente descarte de aparelhos obsoletos se torna um problema de sustentabilidade e também um problema ambiental devido ao seu acúmulo em aterros. A solução para minimizar estes impactos é a reciclagem de seus componentes. Por esta razão, o principal objetivo deste trabalho é estudar o processamento das placas de circuito impresso de telefones celulares através de operações unitárias de Tratamento de Minérios e hidrometalurgia a fim de se recuperar o cobre contido nas placas. Para isso, inicialmente, placas de circuito impresso foram processadas em moinho de martelos, a fim de liberar os materiais, em seguida foi feita a separação magnética do material cominuído. Com a fração não magnética foi feita a separação eletrostática e o material foi separado em: fração condutora, mista e não condutora, com cada fração foi feita a classificação granulométrica e, posteriormente, realizaram-se ensaios de caracterização como pirólise, digestão em água régia e análise química de espectroscopia de emissão óptica por indução de plasma. Os processos hidrometalúrgico aplicados para a recuperação de cobre nas placas de circuito impresso de aparelhos celulares obsoletos envolvem etapas lixiviação com ácido sulfúrico na ausência e na presença de peróxido de hidrogênio. Os resultados da caracterização mostraram que as placas de circuito impresso de celulares após a moagem possuem 24% de cerâmicas; 12,7% de polímeros e 63,3% de metais. Além disso, após a classificação granulométrica e a separação eletrostática os materiais não se concentraram em nenhuma fração especifica, portanto o processamento mecânico visando a recuperação de metais deve contemplar a moagem e a separação magnética. / The technology advancement of electro-electronics devices favors the constant equipment exchange. The frequent disposal of obsolete equipment becomes a sustainability problem and also an environmental problem due to their accumulation in landfills. One possible solution to minimize these impacts is the recycling of their components. For this reason the aim goal of this study is processing of printed circuit boards of mobile phones utilizing unit operation of ore treatment and hydrometallurgy to recover the copper contained in the printed. Therefore, initially printed circuit boards were processed on a hammer mill to release the materials, then it was made magnetic separation of comminuted material. With the non-magnetic fraction was made electrostatic separation in which the material was separated into: conductive, mixed and non-conductive fraction, with each fraction was made grain sized classification and then assays were performed analysis of characterize as pyrolysis, digestion in aqua regia and chemical analysis of inductively coupled plasma atomic emission spectroscopy. Hydrometallurgical processes applied to the cooper recovery in printed circuit boards of obsolete mobile phones, involve steps leaching with sulfuric acid in the absence and presence of hydrogen peroxide. The characterization results showed that the printed circuit boards of mobile phones after grinding have ceramics 24%, polymers 12.7% and metals 63.3%. Moreover, after grain sized classification and electrostatic separation the materials didn\'t concentrate in no specific fraction, therefore the mechanical processing in order to recover metals should include grinding and magnetic separation.
9

Embedded System Design for Real-time Monitoring of Solitary Embedded System Design for Real-time Monitoring of Solitary

O'Brien, Robert Philip 16 March 2015 (has links)
Alzheimer's disease and other forms of dementia cause cognitive disabilities in the afflicted person. As a result, the person with dementia often requires assistance from a primary caregiver. However, while the caregiver is away from the home they are unaware of the person's status and may not be able to find out without returning to the home due to dementia's effects on cognition. In this thesis work, a system of embedded devices is presented which tracks a solitary dementia patient in the home in real-time. The system is composed of three main hardware components. Multiple passive and active sensors are strategically placed to monitor the patient. A number of custom battery-powered embedded systems read the sensors and wirelessly transmit the sensor's values. A central computational node collects the wireless transmissions and analyzes the data. Two algorithms were developed that detect the patient's eating activities and location throughout the home from the sensor data. A web-based user interface was designed that allows a primary caregiver to remotely view the patient's status while away from the home. Numerous trials are performed which test the system's ability to monitor the patient's eating activities and location. The positive results of the trials show that the proposed system is able to detect eating patterns as defined by rules and localize in real-time the patient in the home, accurate to a single quadrant of a room. The proposed embedded system is highly affordable and has two novel features, namely eating detection and patient localization accurate to a single quadrant of any room in the home. Both features use sensors installed in the home and do not require the patient to wear any sensors on their person. The state-of-the-art products currently available are able to localize only to a single room without the patient wearing sensors.
10

Omkonstruktion och arkitekturbyte av autopilot för obemannade farkoster

Andersson, Erik January 2012 (has links)
This thesis has been written at Linköping University for the company Instrument Control Sweden AB (ICS). ICS is a small company located in Linköping that develops software and hardware for Unmanned Aerial Vehicles, UAV. At present, ICS has a fully functional autopilot called EasyPilot but they want to reduce the autopilot’s size to make it more attractive. The purpose of this thesis was to investigate if it was possible to reduce the size of the autopilot and how, in that case, it would be done. It was also necessary to examine whether the old processors should be replaced by new ones and how hard it would be to convert the old software to these new processors. To succeed with the goals many of the old components had to be changed for new, smaller ones. Some less necessary parts were also completely removed. The results showed that the size could be reduced quite a bit, exactly how much is hard to say since no PCB-layout were done. By doing some programming tests on the new components it could be shown that some parts of the old code could be reused on the new design. It was mainly algorithms and other calculations. However, a lot of new code still had to be written in order to successfully convert the old software to the new hardware.

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