• 대한전자공학회논문지SD
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• 제43권10호
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• pp.104-110
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• 2006

오늘날 시스템 온 칩 테스트에 있어서 많은 양의 테스트 데이터, 시간 및 전력 소모는 매우 중요한 문제이다. 이러한 문제들을 해결하기 위해서 본 논문은 새로운 테스트 데이터 압축 기술을 제안한다. 우선, 테스트 큐브 집합에 있는 돈 캐어 비트에 저전력 테스트를 위한 비트할당을 한다. 그리고, 비트할당이 된 저전력 테스트 데이터의 압축효율을 높이기 위해 이웃 비트 배타적 논리합 변환을 사용하여 변환한다. 최종적으로, 변환된 테스트 데이터는 효과적으로 압축됨으로써 테스트 장비의 저장공간과 테스트 데이터 인가시간을 줄일 수 있게 된다.

• 한국전자통신학회논문지
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• 제6권1호
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• pp.61-67
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• 2011

본 논문은 동영상을 효과적으로 부호화하기 위한 새로운 방법에 관하여 연구한 것이다. 움직임 정보를 이용하여 기준 프레임 영상과 상관관계가 적은 프레임 영상에서는 화질을 보장하고, 기준 프레임 영상과 상관관계가 많은 프레임 영상에서는 전체 동영상의 비트율을 보장하는 픽쳐 셋 필터를 제안하였다. 실험 결과, 제안한 동영상 부호화 방법은 기존의 전영역 탐색 블럭 정합 알고리즘에 비하여, 화질은 8.99dB이 향상되고, 압축률은 14.85배가 증가되었으며, 부호화시간은 74.9%가 단축되었다. 그리고, 차영상 알고리즘에 비하여, 화질은 24.87dB이 떨어졌으나, 압축률은 41.94배가 증가하였으며, 부호화시간은 0.9%가 단축됨으로써 좋은 성능을 나타냄을 확인하였다.

• Elastomers and Composites
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• 제16권1호
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• pp.3-13
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• 1981

The purpose of this dissertation is to study the physical properties of cellular rubber products for industrial use. Vulcanization characteristics were investigated by usingcure curve that had obtained by means of Rheometer. The results of physical properties, vulcanization characteristics and foaming states are as follows. 1. The test results for vulcanization characteristics of NR compounds indicated that in the recipe R-1. When accelerator D is used, the optimum conditions of vulcanizate are obtained, while formula R-2 and R-3 have shown higher torgue at curing time, $1{\sim}2$ minutes. Cellular rubber product test in terms of compression set and compression deflection has also met the requirements of SAE. 2. For SBR compounds, S-1 formula was the best in terns of vulcanization characteristics, and for the blowing structure of cellular rubber products, formula S-3 in which accelerator M is added was fair. All other test results, such as compression set and compression deflection properties met SAE requirements. 3. NBR compound (N-1) including accelerator TT was the best in terms of vulcanization characteristic and also blowing structure. All other properties listed above met requirements, particulary for oil resistance test. 4. In the test of EPDM compounds, when mixed accelerator, M and TT, is used(formula E-1) the best results were obtained. Since EPDM is hydrocarbon elastomer, oil resistance test failed. All other properties met the requirement specified in SAE.

• 방송공학회논문지
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• 제27권1호
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• pp.56-68
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• 2022

본 논문에서는 VCM을 위한 다해상도 피처 맵에 대한 압축 방법을 제안한다. 제안하는 압축 방법은 PCA 기반의 변환을 통해 다해상도 피처 맵의 채널 및 해상도 계층 간 중복성을 제거하며 변환에 사용된 기저 벡터와 평균 벡터 그리고 변환을 통해 얻어진 변환 계수를 각각의 특성에 따라 VVC 기반 부호화기와 DeepCABAC을 통하여 압축한다. 제안하는 방법의 성능을 측정하기 위하여 OpenImageV6와 COCO 2017 validation set에 대하여 객체 검출 성능을 평가하며, MPEG-VCM 앵커 및 본 논문에서 제안하는 피처 맵 압축 앵커 대비 bpp와 mAP를 BD-rate 관점에서 비교한다. 실험 결과, 제안하는 방법은 OpenImageV6에서 피처 맵 압축 앵커 대비 25.71%의 BD-rate 성능 향상을 보이며, 특히 COCO 2017 validation set의 크기가 큰 객체들에 대해서 MPEG-VCM 앵커 대비 최대 43.72%의 BD-rate 성능이 향상됨을 보인다.

• 한국의류산업학회지
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• 제19권1호
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• pp.61-69
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• 2017

The purpose of this study is to suggest the sizing system of medical compression stockings for Korean adult men in order to develop compression stockings with excellent dimensional fit reflecting the real human body data. Analyses were conducted on the raw data that the subjects consist of 19~60 aged men of Size Korea 2010 in this study. The stature and weight for the pantyhose stockings, and the ankle circumference and calf circumference for the thighs, knees, and calf support types of stockings were selected as the basic dimension items. The size interval of the pantyhose stockings were 2cm in stature and 2kg in weight. In addition, the thigh, knee, and calf support types of stockings were set with ankle circumference and calf circumference set at 1cm intervals. The designation is the same as KS pantyhose standard, S, M, L, XL. As a result, in the case of pantyhose compression stockings for men, the coverage ratio showed 97.2% in total, with 46.3% for M, 36.5% for L, 7.4% for S, and 6.9% for XL. In the case of thigh type, knee type and calf support types, the percentage of coverage was 99.96% in total, with 57.6% in M, 31.1% in L, 4.7% in S, and 1.6% in XL. The results of this study would help to improve the dimensional conformity of the medical compression stockings for Korean adult men.

• Tribology and Lubricants
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• 제35권4호
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• pp.222-228
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• 2019

As rubber products such as O-rings, which are also known as packings or toric joints, come in regular, long term contact with liquid fuel, they can eventually swell, become mechanically weakened, and occasionally crack; this diminishes both their usefulness and intrinsic lifetime and could cause leaks during the steady-state flow condition of the fuel. In this study, we evaluate the lifetime of such products through compression set tests of FKM, a family of fluorocarbon elastomer materials defined by the ASTM international standard D141; these materials have great compression, sunlight, and ozone resistance as well as a low gas absorption rate. In this process, O-rings are immersed in the liquid fuel of airtight containers that can be expressed as a compression set, and the liquid fuel leakage in a flow rig tester at variable temperatures over 12 months is investigated. Using the Power Law model, our study determined a theoretical O-ring lifetime of 2,647 years, i.e. a semi-permanent lifespan, by confirming the absence of liquid fuel leakage around the O-ring assembled fittings. These results indicate that the FKM O-rings are significantly compatible for fuel tests to evaluate long-term sealing conditions.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2000년도 춘계학술대회 논문집(Proceeding of the KOSME 2000 Spring Annual Meeting)
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• pp.45-51
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• 2000

Investigators who study on combustion in the cylinders of reciprocating piston type internal combustion engines have been encountered embarrassments due to the difficulties of adjusting specific parameter without interfacing other parameters such as cylinder wall temperature composition of gas in the cylinder existence of cylinder lubricant etc. Rapid compression-expansion machine the position and speed of piston of which are able to be controlled by means of a system controlled electrically and speed of piston of which are able to be controlled by means of a system controlled electrically and actuated hydraulically could be utilized as one of the most preferable countermeasures against those difficulties. Several units of rapid compression-expansion machines were developed but the speed up of frequency of piston movement still is the problem to be improved to cope with actual speed of internal combustion engines. Authors designed and manufactured a new rapid compression-expansion machine electrically controlled hydraulically actuated and computer programed and then examined the performance of one. Results of a set of experiments revealed acquirements of certain improvement of frequency of piston movement preserving the stability of system response and reproducing accurate compression ratio of cylinder those are the key function for the in-cylinder combustion experiments of internal combustion engines.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.282-285
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• 2006

This paper analyzed the characteristics of the Lossy JPEG of the meteorological satellite image, and analyzed the quality of the Lossy JPEG compression, which is proper for the LRIT(Low Rate Information Transmission) to be serviced to the SDUS(Small-scale Data Utilization Station) system of the COMS(Communication, Oceans, Meteorological Satellite). Since COMS is to start running after 2008, we collected the data of the MTSAT-1R(Multi-functional Transport Satellite -1R) for analysis, and after forming the original image to be used to LRIT by each channel and time zone of the satellite image data, we set the different quality with the Lossy JPEG compression, and compressed the original data. For the characteristic analysis of the Lossy JPEG, we measured PSNR(Peak Signal to Noise Rate), compression rate and the time spent in compression following each quality of Lossy JPEG compression. As a result of the analysis of the satellite image data of the MTSAT-1R, the ideal quality of the Lossy JPEG compression was found to be 90% in the VIS Channel, 85% in the IR1 Channel, 80% in the IR2 Channel, 90% in the IR3 Channel and 90% in the IR4 Channel.

• Journal of Advanced Marine Engineering and Technology
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• 제24권5호
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• pp.69-75
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• 2000

Investigators who study on combustion in the cylinders of reciprocating piston type internal combustion engines have been encountered embarrassments due to the difficulties of adjusting specific parameter without interfacing other parameters such as cylinder wall temperature, composition of gas in the cylinder, existence of cylinder lubricant etc. Rapid compression expansion machine, the position and speed of piston of which are able to be controlled by means of a system controlled electrically, and actuated hydraulically could be utilized as one of the most preferable countermeasures against those difficulties. Several units of rapid compression expansion machines were developed but the speed up of frequency of piston movement still is the problem to be improved to copy with actual speed of internal combustion engines. Authors designed and manufactured a new rapid compression-expansion machine electrically controlled, hydraulically actuated, and computer programed and then examined the performance of one. Results of a set of experiments revealed acquirements of certain improvement on frequency of piston movement preserving the stability of system response and reproducing accurate compression ratio of cylinder, those are the key function for the in-cylinder combustion experiments on internal combustion engines.

• Journal of the Korean Wood Science and Technology
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• 제42권6호
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• pp.666-674
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• 2014

국산 침엽수재의 용도확장을 위해 열압밀화를 실시하여 압축세트량에 따른 역학적 성능을 조사하였다. 열압밀화 공정에 의해 시험편의 밀도가 크게 향상되었다. 50% 압축 시 대조군 대비 잣나무재가 약 71%, 소나무재가 약 74%, 낙엽송재가 약 76%의 밀도가 증가되었으며, 압축세트량 증가와 함께 시험편의 재질이 균일해진다는 것을 내부밀도분포 분석을 통해 알 수 있었다. 열압밀화에 따른 역학적 성능의 변화는 대조군 대비 50% 압축 시 잣나무재의 경우, 종압축강도가 76%, 휨강도가 83%, 표면경도가 55% 증가하였다. 소나무재는 종압축강도가 69%, 휨강도가 130%, 표면경도가 76% 증가되었다. 낙엽송재의 경우 종압축강도가 77%, 휨강도가 120%, 표면경도가 44% 증가되었다. 국산 침엽수 열압밀화재의 강도성능은 일반적으로 낙엽송재가 가장 높고 잣나무재가 가장 낮았다. 그러나 열압밀화에 의한 강도성능의 증가율은 소나무재가 가장 높았다.