• The KIPS Transactions:PartA
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• v.11A no.4
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• pp.267-276
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• 2004

The modeling methods of routing region used in the automatic placement/routing system are a grid and non-grid. Because the gird method is curbed by its size and a board if the electrical and physical elements on PCB are of small quantity, it has many memories. Therefore, it has demerit which decreases the speed of automatic placement/routing. The Shape-based type, non-grid method, makes the shapes exist as an in dividual element in a memory by using a region-processing method. Each individual element needs very small memory since it has its unique data size. Therefore, this paper aimed to develope the automatic placement/routing system which can automatically place and route the PCB without dissipation of memory at a high speed. To this aim, the auction algorithm method was applied which can make the memories be most rapidly reached from the original point to various destinations. Also, this system was developed by the Visual C++ in the Widows environment of IBM Pentium computer in order to use it in an individual PC system.

• Journal of Power System Engineering
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• v.20 no.6
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• pp.20-26
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• 2016

For power electronic devices, the thermal energy density per unit volume has seen a rapid increase in recent years, owing to the miniaturization and dense integration of electronic components, as well as the continuous development in performance and function. This research examined the validity and reliability of a thermal safety model for managing the heating conditions of TRIAC electronic components. Among the electronic components of a PCB, these can be considered as a heat source. Using the model, the heating conditions of TRIAC components were maintained at their design target levels in the process of developing an LMT motor drive board. In addition, the heating characteristics of the entire PCB were analyzed to verify its thermal safety. Finally, the reliability and validity of the thermal safety model for maintaining the heating conditions of the TRIAC electronic elements at adequate levels was verified using a numerical analysis method.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.148-151
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• 2006

The DC power-bus' resonance is frequently attributed to EMI sources in the PCBs. Subsequently, it will ruin the digital signal integrity within one system or between adjacent systems in the form of conducted or radiated emission. Hence, since it is of importance to examine the PCB's emission, this paper sheds a light on the radiated emission from the power-bus with regards to its resonance modes. A full-wave analysis method is used to calculate the impedance and radiated electric fields and is validated by physics and an EM analysis tool.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.295-295
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• 2000

In this paper, the measurement algorithm of PCB alignment error is developed using image processing. The X-Y-$\theta$ table correcting PCB alignment error is driven by drive module based on microprocessor according to calculation results obtained through image processing procedure. In order to recognize the X-Y-$\theta$ position errors, two fiducial points are marked on PCB and two cameras of ultraviolet rays types are used for detection of the points to capture exactly fiducial points under disturbance of illumination change. Through application for a practical screen printer, the precision control using the developed position control system can be realized about 2.5${\mu}{\textrm}{m}$ in table moving range and 8${\mu}{\textrm}{m}$ in camera processing precision.

• Journal of the Speleological Society of Korea
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• no.79
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• pp.73-75
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• 2007

과거 PCB 제조의 주된 화제는 다양한 산업분야의 발전을 위해 한정된 시간 안에 좀 더 많은 PCB를 양산하는 기술 개발에 집중되어 있었지만, 현재는 비정상적인 공정 상태를 파악함으로써 제조 공정 환경에서의 오류를 줄여 전체 수율을 높이는 방법에 시선을 돌리고 있다. PCB 에칭의 경우 에칭 용액의 상태를 실시간으로 모니터링 하는 것이 중요하다. 본 논문에서는 기존 애칭용액의 상태를 판단할 때 사용되는 ORP센서 대신, RGB센서를 이용하여 실시간으로 용액의 상태를 모니터링 할 수 있는 시스템을 개발하였다. 개발된 시스템을 이용하여, 기존 ORP시스템과의 비교 분석을 및 RGB 센서를 이용한 모니터링 방법이 ORP센서를 이용한 방법 보다 좀 더 쉽고 정확하게 에칭 액의 상태를 모니터링 할 수 있다는 것을 확인하였다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.12
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• pp.73-81
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• 2011

As high speed digital systems continue to use components with faster edge rate and clock speeds, transmission of the digital information, it can bring about many troubles. The increasing requirement for controlled impedance PCBs becomes both a critical success factor and a design challenge to implement a system. Especially, the noise sources in high frequency digital systems include the noise in power supply, ground and packaging, and they destroy the fidelity of signals. Therefore PCB design with impendence matching is needed to improve fidelity of signal in H/W. In this paper, we have developed an impedance control and analysis tool for multi-layer PCB design, and simulates the tracks controlled impedance with the test coupon. So, it can save the design time and support the economical PCB design.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.5
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• pp.586-592
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• 2018

In this paper, HIC with various functions is proposed for the design 140W LED power control circuit. The proposed HIC integrates constant voltage/constant current circuit, short circuit protection circuit, internal constant voltage circuit, and dimmer circuit, thereby reducing the horizontal length of the PCB by 16% comparing with the conventional system. Through various experiments, we verified the performance of each block implemented inside of HIC with numerical results. (Constant voltage variation ratio: 2.9%, dimmer circuit duty variation within 5%, stable short protection at 720 mA) Since the PCB area can be significantly reduced by applying the proposed HIC. It is possible to reduce the PCB manufacturing time which takes up most of the manufacturing time, however, It is expected that the faulted power module can be replaced without replacing the whole PCB, so that maintenance / repair can be made easier.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1284-1290
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• 2001

Objective : PCB cervical instrument is a newly introduced fusion device which comprises cervical plate, cage (spacer) and screw system. It is developed to enhance fusion rate and stability, as well as to reduce complications related to hardware failure. We investigated the efficacy of clinical and radiological results of PCB instrument and Lubboc bone. Methods : From August, 1998 to October, 1999, authors performed 54 cases of anterior cervical interbody fusion with PCB instrument and Lubboc bone. Retrospective analysis was undertaken based on clinical and radiological findings. Clinical improvement was evaluated according to Odom's criteria. Cervical plain films and tomography were taken every 2 months to evaluate the degree of interbody fusion and disc height changes. Results : Bone fusion was observed in 36 cases(90%) over 6 months after operation, and during which time there was no significant interval change. There were 3 cases of hardware dislodgement. Disc height was increased significantly and preserved in all cases. Clinical outcome over good degree was seen more than 94% of patients. Conclusion : Longer follow-up period and comparative studies to similar instrument appear to be necessary, but this instrumentation system has shown high fusion rate and fewer adverse effects in our series. We believe this system might be indicated for the treatment of cervical trauma and degenerative disease in selective cases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4736-4741
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• 2014

This study examined PCB component cleaning on a PCB component surface, which has defects of precipitation type washing (existing rinse method), sealant and foreign material formed in the adhesive process that could not be removed easily. The spin jig was developed for PCB component cleaning, in which the PCB component settled down, to solve the conventional problem of the removal of foreign material with the centrifugal force by high speed rotation. The results are as follows. With decreasing fraction defect in PCB component washing, the development and substrate damage decreased by more than 80% according to the abstergent in the rotary type using the centrifugal force in the existing precipitation type. When the base plate showed a large difference with the time to include the process after washing the design using the existing method, easy attachment and separation of the PCB component could be possible. The washing time was enhanced 90% compared to the existing time. The reliability of the security and washing collaboration of the design and stability of the cleaning process could be secured so that there was no phenomenon of secession, the PCB component fixed for a cleansing rotation jig could maintain a fixed force by the centrifugal force. The stability and reliability of the washing process and the defective rate could be improved to less than 1%.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.772-777
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• 2009

The geometric distortion of image is one of the most important parameters that take effect on the accuracy of optical inspection systems. We propose a new correction method of the image distortion to increase the accuracy of PCB inspection systems. The model-free method is applied to correct the randomly distorted image that cannot be represented by mathematical model. To reduce the correction time of inspection system, we newly propose a grid reduction algorithm that minimize the number of grids by the quad-tree approach. We apply the proposed method to a PCB inspection system, and verify its usefulness through experiments using actual inspection images.