Spelling suggestions: "subject:"printed circuit board"" "subject:"aprinted circuit board""
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Influence of contamination on the long-term reliability of chip-on-board (COB) technologySuthiwongsunthorn, Nathapong January 2002 (has links)
No description available.
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Specialist F.E. algorithms for dynamic analysis of P.C.B.'s simulating variable edge constraints and localised component stiffnessBattoo, R. S. January 1988 (has links)
No description available.
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Design and development of the hardware for an automated PCBA inspection and rework cellGeren, Necdet January 1993 (has links)
No description available.
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The effect of diffusion layer on throwing powerHamshow, M. H. January 1986 (has links)
No description available.
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Model and Analysis of Transmission Lines on Flexible Printed Circuit for the Video Driver CircuitHuang, 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.
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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.
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Embedded System Design for Real-time Monitoring of Solitary Embedded System Design for Real-time Monitoring of SolitaryO'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.
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A Study of Theory of Constraint Application in Printed Circuit Board Products Mixed Decision Making .Huang, Kuo-Feng 04 July 2003 (has links)
Abstract
One of the features in Taiwan market is price competition. What makes it even worse are the outflow of investment, more demand on environmental protection, increase of labor cost, and the limit of national policy. These factors make business hardly earn profits. And therefore, how to gain reasonably with limited resources and survive in the competition are the difficulties we need to overcome in Taiwan.
Printed Circuit Board played a key role in ¡§Taiwan Financial Miracle¡¨ for the past 10 years. However, the manufacturers now have no choice but to search for new niche to meet the change on the whole business environment. The headquarters staying in Taiwan have to face even more harsh conditions, which come from the demand of cost-down, the price competitions among the same industry. Therefore, it becomes essential to adjust Product Mixed in order to fit the insufficient Product Resources.
My study puts focus on ¡§Most Constrained Station¡¨ from the Theory of Constraint. It helps PCB manufacturers, who suffers slim profit, find out the best Products Mixed in accordance of Throughput Contribution. Each product brings different profit and cost. Some may share common resources, and some may not, when they are put in the process line. Therefore, to continue forward in the age of slim-profit, the complex of Product Mixed and earnings becomes prominent. Studying Theory of Constraint, I aim to bring forth the best solution on processing contribution by means of figuring out the Throughput Chain in Most Constrained Station and analysis of application on Most Constrained Station. And then I will conclude with the best production strategy for the PCB manufacturer as the main thesis of the research.
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Effects of Discontinuity Structures on EMI in Multi-Layer Printed Circuit Board Using Transmission Line ModelYu, Ming-Hsuan 23 July 2008 (has links)
In this thesis, we study the discontinuity structure electromagnetic effect of multilayer printed circuit board in three sections. In first section, we introduced a modeling approach which is based on transmission line theory , and simulated with a series of test boards ,such as regular and irregular power delivery system and multilayer with via structure, finally ,we confirmed that the modeling approach is an efficient simulation and agreed fairly well with 3D full-wave method. In second section, we demonstrated the return current is disrupted at the via or broken at the power / ground plane with slots , the impedance becomes extremely high at the resonance frequencies of the power / ground plane cavity and via could be a major cause of the simultaneous switching noise generation, signal quality problem, and edge radiated emission in multi-layer PCB. In final section, we provided a effective reduction mechanism to eliminate the noise or EMI, which has been achieved using island with shorting vias and combining with the modeling approach can simulate and estimate effectively.
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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.Viviane Tavares de Moraes 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.
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