• Proceedings of the KSR Conference
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• 2002.10a
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• pp.446-452
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• 2002

In this paper, it is proposed that an existing utilizing methods of FMEA, one of the potential failure cause analysis of the systems and products, is reviewed and more efficient advanced application scheme and improvement idea is suggested. In present, in company with Products liability laws which are being conducted, this proposed methods are intended to be applied at systems which require high-reliability and safety.

• Smart Media Journal
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• v.10 no.3
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• pp.54-59
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• 2021

Flight data acquired through flight instrumentation equipment during aircraft development play an important role in aircraft development and performance improvement. Therefore, as the reliability of flight instruments is required, inspection systems to check the soundness of flight instruments are very important. In this paper, we analyze the existing test system for flight data instrumentation equipment and present improvements in the hardware and software aspects of the test system. Based on this, we design and implement a test system with improved performance and present test results. Test system with improved performance improves cost savings, flexible application, and maintenance compared to the existing test system. Therefore, the robustness of the instrumentation equipment can be obtained, which can be expected to improve the reliability of flight data.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.656-662
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• 2009

In this paper, the heat resistance reliability of an axial smoke exhaust fan was investigated. An axial smoke exhaust fan should be capable of operating at $250^{\circ}C$ for 2 hours. The heat resistance reliability was evaluated by the heat resistance reliability test. A B10 life with a 90% confidence level was estimated to be about 48 minute. The failure occurred in the motor due to high temperature. The main failure mechanisms of the motor were melting of bond and insulating paper and burning of insulating materials in the coil. The heat resistance reliability was improved by changing the way to unite the core and the coil and by replacing the insulating paper and the insulating materials of the coil. A B10 life with a 90% confidence level of a modified axial smoke exhaust fan was estimated to be over 120 minute.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.1
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• pp.21-25
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• 2015

Bending fatigue characteristics of Cu films and $8{\mu}m$ width Cu interconnects on flexible substrates were investigated, and fatigue reliability improvement was achieved through Mo-Ti alloy adhesion layer. Tensile bending fatigue reliability of Cu interconnects is 3 times lower than that of Cu films, and even compressive bending fatigue reliability of Cu interconnects is 6 times lower than that of Cu films. From these results, mechanical crack formation could be fatal in Cu interconnects. With Mo-Ti adhesion layer, fatigue reliability of Cu films and interconnects were enhanced due to the increase of adhesion strength and the suppression of slip induced crack initiation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.47-53
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• 2020

The purpose of this study was to increase product reliability by improving the durability of the breech block for a 30mm Automatic Gun. The breech block is a key component of a gun that functions as chambering, closing, and extracting. The breech block requires high reliability, which needs to be improved because cracks of a breech block can occur early in operation. Cause analysis confirmed that the crack is caused by repeated impacts. Therefore, the following improvement measures were studied, and the effects were demonstrated using a firing test. The energy of impact absorption was increased by changing the material, and the stress concentration was mitigated by increasing the value of R. In addition, the fatigue life was increased by adding Shot-peening, deleting chromium plating, and changing the forging method. The firing test did not show firing trouble for up to 5,000 rounds. The start timing of the crack was delayed, and the depth was small. Therefore, the improved product was more durable than the existing product. This study can be used as a useful reference when assessing the improvement of the durability of similar products, life study, and criteria for crack acceptance.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.3
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• pp.51-63
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• 1999

The effects of high filler loading technique on the reliability of epoxy molding compound (EMC) as a microelectronic encapsulant was investigated. The method of high filler loading was established by the improvement of maximum packing fraction using the simplified packing model proposed by Ouchiyama, et al. With the maximum packing fraction of filler, the viscosity of EMC wart lowered and the flowability was improved. As the amount of filler in EMC increased, several properties such as internal stress and moisture absorption were improved. However, the adhesive strength with the alloy 42 leadframe decreased when the filler content was beyond the critical value. It was found that the appropriate content of filler was important to improve the reilability of EMC, and the optimum filler combination should be selected to obtain high reliable EMC filled with high volume fraction of filler.

• Journal of Digital Contents Society
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• v.7 no.3
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• pp.169-174
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• 2006

In recent years, RFID is widely used in industrial applications including factory, material flow, logistics and defense areas. In this paper, The convolutional encoding and viterbi decoding is also implemented to improve the system performance. in an FPGA chip. The used convolution code is constraint length K=3 and rate R=1/2. The length of command frame and response frame is total of 48bits consisting of SOF 8 bits, command 16 bits, CRC 16 bit, and EOF 8 bits. And also the frame error rates are measured under the channel of line-of-sight and non line-of-sight, respectively. The performances are analyzed with FSK modulation only and FSK modulation added with convolutional encoding. These two measured results are compared with that of a RFID system with ASK modulation.

• Journal of Advanced Navigation Technology
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• v.11 no.3
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• pp.288-295
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• 2007

In this paper, we proposed two systems, STTC scheme and STBC-TCM scheme, to enhance the reliability of HDR-WPAN system and analyzed BER(bit error rate) performance of the proposed systems over the slow fading channel. The proposed systems had a diversity gain and coding gain without increasing an additional channel bandwidth. However, in terms of reliability, about 4dB improvement at BER=$10^{-4}$ was obtained by the STBC-TCM scheme. In addition, HDR-WPAN system with STBC-TCM scheme had a linear rise in system complexity of ML(maximum likelihood). From the results, STBC-TCM scheme was more appropriate to improve the reliability and channel efficiency and to reduce complexity of HDR-WPAN system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.826-829
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• 2007

In this paper, we proposed two systems, STTC scheme and STBC based on STTC scheme, to enhance the reliability of HDR-WPAN system and analyzed BER(bit error rate) performance of the proposed systems over the slow fading channel. The proposed systems obtained a diversity gain and coding gain without increasing an additional channel bandwidth. However, in terms of reliability, about 4dB improvement at $BER=10^{-3}$ was obtained by the STBC based on STTC scheme because of the additional diversity gain of STBC. From these results, STBC based on STTC scheme was more appropriate to improve the reliability and channel efficiency of HDR-WPAN system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.120-121
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• 2013

Recently, our country is to be diversification a leisure activity and tourism form by income level rise and traffic circumstance improvement. But Basic facilities expropriated these leisure activities have built an insufficient condition. Also, Building a facility, Introduced tools and materials import the whole quantity. Therefore, In this paper, it builds a tension mooring unit to use EPDM and Kevlar R29 and it develops a domestic marine circumstance through reliability based on robust design. It contributes to marine leisure culture activation and industry development.