• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2007년도 추계종합학술대회
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• pp.493-496
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• 2007

최근 유비쿼터스 시대에 진입하면서 PDA,PMP, Smart Phone 등의 휴대형 정보기기의 보급으로 임베디드 시스템의 기능이 다양해지고 멀티미디어 기능이 강화됨에 따라 시스템이 처리해야할 정보의 양도 늘어나고 있다. 이에 따라 시스템은 대용량의 전력 공급이 필요하게 되었다. 그러므로 Battery라는 제한적인 에너지원을 사용하는 휴대형기기에서 전력 관리는 중요한 이슈가 되고 있다. 본 논문에서는 미아방지용 스마트 디바이스에 최적화된 젼력 관리 솔루션을 제공하는데에 초점을 맞추었다. CPU는 ARM9 Core를 사용하고 Windows CE 5.0을 Porting 하였다.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2003년도 기술심포지움 논문집
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• pp.53-58
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• 2003

The Wafer Level Packaging is one of the most important technologies in the semiconductor industry today. Its primary advantages are its small form factor and low cost potential for manufacturing including test procedure. The CASIO's WLP samples, application example and the structure are shown in Fig.1, 2&3. There are dielectric layer , under bump metal, re-distribution layer, copper post , encapsulation material and terminal solder .The key technologies are 'Electroplating thick copper process' and 'Unique wafer encapsulation process'. These are very effective in getting electrical and mechanical advantages of package. (Fig. 4). CASIO and CMK are developing a new System Packaging technology called the Embedded Wafer Level Package (EWLP) together. The active components (semiconductor chip) in the WLP structure are embedded into the Printed Wiring Board during their manufacturing process. This new technical approach has many advantages that can respond to requirements for future mobile products. The unique feature of this EWLP technology is that it doesn't contain any solder interconnection inside. In addition to improved electrical performance, EWLP can enable the improvement of module reliability. (Fig.5) The CASIO's WLP Technology will become the effective solution of 'KGD problem in System Packaging'. (Fig. 6) The EWLP sample shown in Fig.7 including three chips in the WLP form has almost same structure wi_th SoC's. Also, this module technology are suitable for RF and Analog system applications. (Fig. 8)

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.857-861
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• 2004

An active method that improves low frequency characteristics of a reverberation chamber has been proposed. Spatial uniformity of sound pressure at low frequency has been increased by applying active noise control system. The system acts as frequency selective damping materials, which decreases resonance at low frequency and leave high frequency sound field as it is. Linearity of the chamber, which is essential for sound power measurement in the chamber, is guaranteed since fixed control logic has been adopted. Simple application and tests have been done in a small sized rectangular reverberation chamber which has 400Hz cutoff, Loud speakers were used to simulate a noise source and to construct an active noise control system. The spatial distribution of a sound field at 250Hz, 315Hz and 400Hz bands has been measured before and after control. The standard deviation of sound field has been decreased from 3.4dB to 2.5dB. The results show the possibility of active control system as a sound diffuser.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 추계학술대회 논문집
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• pp.117-118
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• 2013

Recent global warming to the promotion of electric vehicles (EV), plug-in hybrid (PEV), including the next generation of cars and solar power, wind power and other renewable energy, and next-generation power grid (smart grid) are getting attention. In addition, the system utilizes the battery life in the industry and the convenience of a variety of social systems, economics, environmental impact, and the inherent potential to change significantly, and you can not walk into a next-generation industrial strategy and the need increases more and more present, and its early commercialization In order to do this, as well as a key energy source, the battery charger for charging efficiency technologies is essential. In this paper, fast charge multiple battery modules and optional modules that can charge distribution charge will be introduced.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2002년도 추계학술발표논문집
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• pp.182-184
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• 2002

본 논문은 최소한의 정보량을 가지고 높은 안전성을 제공하는 타원곡선과 스마트 카드의 PIN을 동시에 이용하는 이미지 분배에 대한 프로토콜을 제안한다. 타원 곡선 공개키 암호 알고리즘의 이용은 이미지 분배과정에서 필요한 계산 속도를 빠르게 함으로써 실제로 분배 시스템을 구현하였을 때 보다 효율적이고 편리한 이용환경을 제공할 수 있고 알고리즘과 스마트 카드의 고유 PIN을 이용하기 때문에 가지는 높은 안전성은 사용자들에게 이미지 분배하는 과정에서의 지불시스템에 대한 신뢰성을 가지게 할 수 있다. 이와 같이 타원곡선 공개키 암호 알고리즘과 스마트 카드를 이용해 설계된 이미지 분배과정에서의 지불시스템은 이동 컴퓨팅 환경에서도 효과적으로 사용될 수 있을 것이다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.5-8
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• 2002

The issues associated with the application of CFD for ship design are addressed. It is quite certain that the CFD tools are very useful in evaluating hull forms a prior to traditional towing tank tests. However, the time-consuming pre-processing is an obstacle in the daily application of CFD tools to improve hull forms. The accuracy of computational modeling without sacrificing the usability of CFD system is also to be assessed. The wave generation is still predicted by using potential panel methods, while velocity profiles entering into propeller plane is solved using turbulent flow solvers. The choice of turbulence model is a key to predict nominal wake distribution within acceptable accuracy. The experimental data for CFD validation are invaluable to improve physical and numerical modeling. Other applications of CFD for ship design than hull form improvement are also given. It is certain that CFD can be a cost-effective tool for the design of new and better ships.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.448-452
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• 2008

2-stroke marine diesel engine has generally one exhaust valve and three fuel injection nozzle which are key component for engine's performance and combustion. Fuel injection and exhaust valve driving system are driven by rotating of camshaft. Rotation of crank shaft drives the cam shaft through gear train that is composed of $3{\sim}4$ gear wheels. Gear column supporting the gear wheel has to bear against the dynamics forces by engine running as well as gearing forces. In this paper, structural analysis for engine structure and fatigue strength assessment of welded joint is shown. Repeatedly full cyclic simulation during one cycle is performed to investigate the structural behavior of engine. Fatigue analysis is carried out based on IIW using submodeling technique to obtain more detailed stress distribution.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2012년도 전기공동학술대회 논문집
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• pp.125-126
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• 2012

The key issues for the reduction technologies of the exhaust gas from diesel engine being developed are to reduce particulate matters and NOx. Performance of NOx removal in SCR process depends on such various factors as catalyst factors(catalyst composition, shape, velocity, etc.), exhaust gas temperature and velocity distribution. In this study checked flow uniformity with the flow characteristics in the SCR reactor by using STAR CCM+. The pressure drop of experiment and simulation had similar result more than 90% at catalytic Cell. Also, flow uniformity calculated about 0.9036 ant 1st catalytic ind SCR reactor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.265-267
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• 2002

In this paper, the communication between Over-Current Relay agents is realized using DNP(Distributed Network Protocol), which is the standard communication protocol of distribution automation system in KEPKO. The key words in OCR agent communication are defined and represented by use of DNP application function code. And the DNP index for OCR agent is defined. The proposed communication scheme is tested by use of Communication Test Harness, a test tool for DNP protocol to show its soundness.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.241-242
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• 2015

According to globalization of world economy on distribution and sales, logistics and transportation parts are play important role. Especially, it important to know and study how to choose right transport route and which is the key factor of route choice model in multimodal transport system. Thus this study aims to consider 4 main factors: cost, delivery time, freight, and logistics service factors additionally dividing into 13 sub factors and object is forwarders between Mongolia and Korean freight transport. The survey is based on AHP through interview with company officials. The paper provides empirical insights about current status of Mongolian forwarders and difference of the important factors between transportation modes. Result shows that time factor is role factor to choose transport route and then cost factors. Additionally, this study shows 2 different route choose factors between air transport and shipping transport forwarders.