• 한국통신학회논문지
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• 제35권2B호
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• pp.352-360
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• 2010

IPTV나 Mobile IPTV 같은 IP 기반의 방 통 융합형 멀티미디어 서비스는 사용자 인지적 QoE가 보장된 서비스를 제공하는 것이 절실하다. 본 논문에서는 실시간 Mobile IPTV 서비스시 다양한 IP망의 조건에 따라 발생하는 에러의 영향으로 열화된 컨텐츠의 손상 정도를 보다 정확하고 효율적으로 평가하기 위한 방안을 제안하였다. QoE를 고려한 실시간 전송시 측정을 위해서 손상된 프레임의 효율적 정합 및 측정 방법을 보여 주었다. 제안된 알고리즘은 실시간 전송 스트림의 각 프레임으로 부터 디지털화된 컨텐츠의 밝기 정보를 추출하여 분석하며 블러, 블록, 에지 비즈니스, 컬러 에러 등 QoE 요소들을 RR 기반의 측정 파라메터로 활용하여 평가하였다. 제안된 방안의 정확성을 증명하기 위해서 원 소스 컨텐츠와 손상된 컨텐츠를 비교 분석하였다.

• 인지과학
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• 제21권1호
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• pp.145-156
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• 2010

본 논문은 원본 디지털 영상을 보호하고 동시에 저작권 정보 등을 저장할 수 있는 콘텐츠 기반 정지 영상 보호에 관한 새로운 방법을 제시한다. Gradient값을 이용한 기존의 알고리즘은 픽셀 단위의 소벨 연산자 알고리즘이 적용되었기 때문에 외부 공격에 대하여 상대적으로 민감하게 반응하고 저작권 정보 등을 정확하게 검출하지 못하는 단점이 있다. 따라서 본 논문에서는 이러한 약점을 보완하기 위하여 블록 단위의 연산이 이루어지는 OCL(Orientation Certainty Level)을 적용하여 특징점을 선택하였다. 실험 결과 기존의 알고리즘에 비해 변화가 심한 공격에서도 99% 이상의 높은 검출도를 나타내는 것을 볼 수 있고 특히 회전 공격에 대해서는 10%이상의 큰 성능 향상을 보여주고 있다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권3호
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• pp.180-191
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• 2016

Purpose: The purpose of this study was to develop the accelerated life test method for Constant Electrical Potential Electrolysis gas sensor (CEPE gas sensor). Methods: The parts and modules of CEPE gas sensor were analyzed by using Reliability Block Diagram (RBD). Failure Mode and Effect Analysis (FMEA) and Quality Function Deployment (QFD) methods were performed for each part to determine the most affecting stress factor in its life cycle. The long term testing was conducted at three different dry heat levels and the acceleration factor was developed by using Arrhenius relationship. Conclusion: The acceleration factor for CEPE gas sensor was developed by using FMEA, QFD, and statistical analysis for its failure data. Also qualification tests were designed to meet the target life.

• 전기전자학회논문지
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• 제21권2호
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• pp.142-145
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• 2017

현재 활용되는 영상 데이터가 고화질 고화소 추세이며, 정보통신기술의 발달로 인해 이미지 데이터의 사이즈와 양이 기하급수적으로 증가하고 있다. 이러한 영상데이터를 효율적으로 처리한다면 다양한 컨텐츠로 활용할 수 있지만 기존의 단일컴퓨터로 처리하기에는 늘어나는 데이터를 처리하기에는 한계가 있다. 본 논문은 분산 처리 프레임워크인 Hadoop을 이용하여 번호판 인식 시스템을 제안한다. SequenceFile 포맷을 이용하여 매퍼당 여러 개의 이미지 데이터를 가지고 있는 데이터 블록을 인풋으로 받아 번호판 인식을 수행한다. 실험결과 하둡의 데이터 노드 1개와 비교하여 데이터 노드 16개에서 최대 14.7배의 속도향상을 보였으며, 데이터 셋의 크기를 10배 증가하여도 데이터 노드가 점진적으로 늘어남에 따라 번호판 인식 속도의 강인함을 확인하였다.

• 한국지반공학회지:지반
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• 제13권2호
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• pp.39-54
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• 1997

연약지반 개량공법으로 국내에서 생산된 플라스틱 보드 드레인(PBD)이 많이 사용되고 있으나 이들에 대한 물리적 성질 및 배수성능의 검증이 미약한 실정이다. 또한 PBD의 웰 레지스턴스(well resistance)에 크게 영향을 미치는 공기(기포)의 영향에 대한 인식이 부족하다고 판단된다. 따라서 본 연구에서는 대형 실험장치를 이용하여 먼저 국산 PBD를 중심으로 물리적 성질 및 배수성능 시험을 실시하여 제품의 질적 수준을 규명하고 대표적인 국외제품과 비교했다. 아울러 PBD재의 꺾임 부분에 누적된 공기(기포)가 통수능력에 지장을 초래하는 것을 재확인하였으며 현장에서 적용할 수 있는 진공펌프를 이용하여 필기(기포)를 제거시키므로써 통수능력의 회복이 가능하다는 것을 나타냈다.

• 한국항공우주법학회:학술대회논문집
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• 한국항공우주법학회 2008년도 제40회 국제학술발표대회
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• pp.153-161
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• 2008

What was once known as common courtesy is rapidly disappearing in the air travel industry, and the violent behavior known as air rage is a constant threat. Once sought after by other industries for advice because of its expertise in customer service, the air travel industry has now slipped to the lowest rungs of companies with unhappy customers. As airlines cut corners in order to avoid bankruptcy, passengers' patience is tested by the stress of flight delays, crowded airports and close packed seating on airplanes. This article examines the situation, strategies used by passengers and ways the airline industry might better inspire courteous behavior in passengers. A cultural expectation of entitlement and competitiveness for limited resources has led to a breakdown in civilized behavior throughout society, both in the United States and internationally. Air travelers faced with rude and intrusive behavior from others on the flight are beginning to find their own ways of coping, such as high quality headphones to block offensive noises, and mechanical devices to keep the seat in front from reclining to the point where it hits their knees. The most potentially effective remedies will come from airlines that enlist cooperation by offering effective passenger education and possibly even incentives. Acceptable airline behaviors need to be plainly defined and stressed for passengers, both before boarding and onboard. In this paper, some methods are suggested to motivate passengers and to inspire courteous behavior.

• KIEAE Journal
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• 제8권4호
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• pp.43-48
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• 2008

One of the most important factors in determining the quality of living environment is daylighting. Especially its influence in the psychological and biological life of human beings cannot be underestimated. Therefore, lots of researches have been given to develop a more efficient daylighting system. The sunlighting system, one of many developed systems, has been developed and applied in various ways. However, the high cost of sunlighting system has been the most difficult stumbling-block in making it commercial. However, as domestic apartment houses tend to be more luxury, life environment becomes a very important factor more than cost in building apartment house. Therefore, it would be possible to adopt sunlighting system in the non-window areas such as a restroom in an apartment house. This research is a preliminary work in order to measure a possibility of applying sunlighting system in an apartment house. In order to do so, I measure Sunlight Illuminance Ratio in various areas of apartment house. As a result, in case of a residential-commercial building, areas such as kitchen, restroom, and entrance are relatively weak-lighting areas. In case of a traditional apartment house, restroom and entrance are relatively weak-lighting areas. For that reason, a special lighting support is needed in these areas.

• 한국식품영양과학회지
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• 제28권5호
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• pp.1180-1186
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• 1999

A wide ranges of chemicals released into the environment have potential to interfere with physiological and development process by disrupting endocrine pathways. Endocrine system embraces a multitude of mechanisms of action, including effect on growth, behavior, reproduction and immune function. These environmental endocrine disruptors are present in environment and pose potential health consequences to human and wildlife. The best known form in endocrine distruptors involves substances which mimic or block the action of natural hormone in the body. Endocrine disruptor have been variously defined as exogenous agents that interfere with the synthesis, secretion, transport, metabolism, binding action or elimination of the natural hormones in the body which are responsible for the maintenance of homeostasis, reproduction developmental and/or behavior. Many compounds polluted into the environment by human activity are capable of disrupting the endocrine system of animals, including fish, wildlife, and humans. Among these chemicals are pesticides, industrial chemicals, and other anthropogenic products. It has been alleged that several adverse effects on human health are linked with exposure to chemicals which are claimed to be endocrine disrupters, that is, increased incidence of testicular, prostate and female breast cancer, time dependent reductions in sperm quality and quantity, increased incidence of cryptorchidism (undescended testicles) and hypospadias(malformation of the penis), altered physical and mental de velopment in children. This observation is currently the only example of chemically mediated endocrine disruption which has resulted in a clear effect at the population level.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.113-120
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• 2005

Soil nailing system can be mentioned to a method of supporting as the shear strength of in-situ soils is increased by passive inclusions. In the general soil nailing system, facing walls are used in two kind of a lattice concrete block or a cast in placed concrete wall. A case of lattice concrete blocks is used in slow slopes greater than 1:0.7. Also, a case of a cast in placed concrete wall is used in steep slopes less than 1:0.5. The cast in placed concrete walls are constructed to 30cm thick together with a shotcrete facing. In this study, the assembling soil nailing method as a new soil nailing system is proposed. This method is constructed assembly using precast concrete panels. Therefore ability of the construction and quality of the facings can be modified than a usual soil nailing system. Also, this method can be obtained the effects that a global slope stability increase, as precast concrete panels is put on cutting face after excavating a slope.

• Journal of Communications and Networks
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• 제12권2호
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• pp.168-173
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• 2010

Error concealment techniques are significant due to the growing interest in imagery transmission over error-prone channels. This paper presents a spatial error concealment technique for losslessly compressed images using least significant bit (LSB)-based data hiding to reconstruct a close approximation after the loss of image blocks during image transmission. Before transmission, block description information (BDI) is generated by applying quantization following discrete wavelet transform. This is then embedded into the LSB plane of the original image itself at the encoder. At the decoder, this BDI is used to conceal blocks that may have been dropped during the transmission. Although the original image is modified slightly by the message embedding process, no perceptible artifacts are introduced and the visual quality is sufficient for analysis and diagnosis. In comparisons with previous methods at various loss rates, the proposed technique is shown to be promising due to its good performance in the case of a loss of isolated and continuous blocks.