• 한국세라믹학회지
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• 제34권3호
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• pp.257-264
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• 1997

MPB조성영역에 MnO2를 첨가한 압전체를 제조하여 분극처리후에 반복압축응력을 부여함에 따른 압전열화 현상을 조사하고 분극처리 전후의 굽힘강도의 변화 및 파괴특성을 연구하였다. MnO2를 0.25wt.% 첨가한 시편에서 가장 적은 열화현상이 일어났다. 굽힘강도는 분극처리 후 하중방향에 평행한 방향으로 분극처리한 시편이 분극처리 전보다 높은 강도를 나타내었고, 수직한 방향으로 분극처리한 시편은 낮은 값을 나타내었다. 이는 분극처리시 발생하는 전계방향으로 압축잔류응력, 직각방향으로 인장잔류응력 때문인 것으로 사료된다.

• 소성∙가공
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• 제12권1호
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• pp.60-65
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• 2003

HIP diffusion bonding of Ni-based superalloys, cast Mar-M247 (MM247) and Udimet 720 (U720) powder, was experimentally and numerically studied. Subsolvus HIP treatment was optimized by investigating the variations of high temperature tensile properties of HIP-bonded specimens with powder size, HIP'ing time, etc. While the tensile strength at high temperatures showed no detectable changes, the tensile elongation and reduction in area were slightly increased as the powder size decreased from -140 mesh to -270 mesh. While as-HIP'ed U720 showed a high tensile strength comparable to that of lorded U720 alloy, the HIP diffusion-bonded specimen showed a strength lower than the forged U720 alloy and the cast MM247 alloy The increase of HIP'ing tune from 2 hours to 3 hours resulted in a rapid risc of tensile strength and elongation due to the disappearence of microvoids in the cast MM247. FEM simulation for HIP process was conducted by applying the McMeeking micromechanical model, which uses power-law creep model as constitutive equations. ABAQUS user subroutine CREEP with an implemented microscopic model was used for the simulation. Numerical simulation was shown to be essential for the near-net shape manufacturing as well as the HIP process optimization.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.109-112
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• 2007

In this paper, a mathematical modeling was developed to simulate 1kW class air cooled Polymer Electrolyte Membrane Fuel Cell(PEMFC) system. The proposed modeling was conducted under SIMULINK based environment. The model ing was developed based on the thermodynamic and chemical equilibrium. The objective is to design and implement the entire fuel cell system model ing including the system controller modeling. The fuel cell process and the control system modeling should have to be connected with each other simultaneously， therefore the two types of modeling influences each other when the system simulator run. The fuel cell modeling libraries are simulated using the SIMULINK under the thermodynamic and chemical equilibrium base. The PID controller application was designed and developed to test the process modeling and verify it. This the prototype development of the fuel cell system to design and test more complicate fuel cell systems, like the residential power generation system. The simulation results was compared to the real PEMFC system performance. We have achieved the reasonable accordance with the Lab test and the simulation results.

• 정보처리학회논문지D
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• 제11D권7호
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• pp.1435-1442
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• 2004

최근 소프트웨어 개발 방법론 중 소프트웨어 부품화하고 이를 조립${\cdot}$합성하여 새로운 어플리케이션을 개발하는 방식의 CBD 방법론이 많이 연구되고 있다. 그러나 CBD 방법론은 시스템의 기능적인 특성을 중심으로 분할하는 경향이 많아 컴포넌트에 대한 추론, 문서화, 코드의 이해를 어렵게 하는 단점이 있다. 따라서 본 논문에서는 영역지향 프로그래밍 기술을 CBD 방법론과 UML 다이어그램에 적용하여 CBD 방법론의 단점을 보완함으로써 컴포넌트의 재사용을 용이하게 하고 시스템 개발 시간 단축과 개발비용의 감소를 유도하였다.

• 한국컴퓨터정보학회논문지
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• 제10권5호
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• pp.323-332
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• 2005

본 논문에서는 웹 기반에서 학습자의 학습 성취도 향상을 도모할 수 있는 다양한 학습 내용 구성 환경을 제공할 수 있으며, 실시간으로 과제물을 평가할 수 있는 e-Learning 시스템을 개발하였다. 우리는 학습자의 특성과 흥미를 유발할 수 있는 특징들을 고려하여 문제풀이와 Quiz를 갖춘 학습 내용 구성을 개발하여, 학습자 스스로가 동적으로 다양한 학습 내용 구성 환경을 선택할 수 있도록 하였다. 그리고 과제물 시스템은 객관식 및 서술형 과제물을 교수자와 학습자간에 상호 실시간으로 처리할 수 있도록 개발하였다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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• pp.153-156
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• 2004

This Paper deals with speed control of DC servo motor using a Fuzzy-Sliding observer. Speed sensor detect a speed of rotor continuously. But It have a limit as a driving speed to detect speed precisely. So it is problem to improve the performance of the driving system To solve the problem, it is studied to detect a speed of DC motor without sensor In particular, study on the method to estimate the speed using the observer is performed a lot. In this parer, the gain of the observer is properly set up using the fuzzy control and sliding observer that have a superior transient characteristic and is easy to implement compared the exist ing method is designed. It estimate the derivative of the armature current directly using the armature current measured in the DC motor. It estimate the speed of the rotor using the differentiation. It is Proposed speed sensor less control method using the estimated speed. Optimal gain of Luenberger observer is set up using the fuzzy control and adapted speed control of DC servo motor. It is proved excellence and feasibility of the presented observer from the comparison tested a case with a speed sensor and a case without a speed sensor which used a highly efficient drive and 200W DC servo motor start ing system.

• 복식
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• 제25권
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• pp.105-118
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• 1995

Chinese shroud through literature are as follows. 1. Taetae, SimeI, P'oo, Hansam, Ko, Mal, Nukpaek , Kwatu, Ch'ungi, Pokkn, Myokmok, Ri, Aksu, Mo and m were used the most in China. 2. The cloths of Chinese shroud were p'o, Paek , Kyon and Kum. The colors of the Chinese shroud were Hyon, Hun and white. 3. The size of the Chinese shroud is as follows . The size of the Ch'ungi was similar to the size of jujube kernel, the length of Myokmok was one Chk two Chn or one Chk two Chn or one Chk five Chn, the length of Aksu was one Chjk two Chn and it's width was five Chn. The chil of Mo reached the hands and the length of Swae was three Chk and the length of m was five Chn. 4. In Chinese shroud, , cotton was put in P'oo. Aksu was tide by the strings at two corners. Myokmok was tied by the strings of four corners. The tip of the m was divided and Mo warpped the whole body. 5. The clothes of Soryom was nineteen Ch'ing. The clothes of Taeryom in Kum were one hundred Ch'ing in the Chinese. The impliment of Soryon were Kum, kyo, SangeI, SaneI, Ch'im , Yok and Kyon in the Chinese shroud. In the case of the implement of TAeryom, the chinese shroud had Kum , Kyo, SangeI, Sane, Ch'im and Yok.

• 복식
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• 제25권
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• pp.117-118
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• 1995

Chinese shroud through literatures are as follows. 1. Taetae, Sime i, P'oo, Hansam, Ko, Mal, Nukpaek, Kwatu, Cu'ungi, Pokk n, Myokmok, Ri, Aksu, Mo and m were used the most in China. 2. The cloths of Chinese shroud were p'o, Paek, Kyon and Kum. The colors of the Chinese shroud were Hyon, Hun and white. 3. The size of the Chinese shroud is as follows. The size of the Ch'ungi was similar to the size of jujube kernel, the length of Myokmok was one Ch' k two Ch'on or one Ch' k five Ch'on, the length of Aksu was one Ch' k two Ch'on and it's width was five Ch'on. The chil of Mo reached the hands and the length of Swae was three Ch' k and the length of m was five Ch'on. 4. In Chinese shroud, cotton was put in P'oo, Aksu was tide by the strings at two corners. Myokmok was tied by the strings of four corners. The tip of the m was divided and Mo wrapped the whole body. 5. The clothes of Soryom was nineteen Ch'ing. The clothes of Taeryom in Kun were one hundred Ch'ing in the Chinese. The impliment of Soryom were Kum, Kyo, Sange i, Sane i, Ch'im, Yok and Kyon in the Chinese shroud. In the case of the implement of Taeryom, the chinese shroud had Kum, Kyo, Sange i, Sane i, Ch'im and Yok.

• 반도체디스플레이기술학회지
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• 제10권2호
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• pp.13-17
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• 2011

We have developed a new energy-consuming monitoring system that has made it possible to measure the energy consumption of a gas scrubber, one of semiconductor processing equipments, and installed this system to the gas scrubber under operating at a manufacture site. Using this system, we have measured consumptions of electric power and processing gas consumed at standby to operating mode. In case of the gas scrubber, processing gas flows continuously into it at standby and operating mode. Therefore, if the electric power has been supplied, the processing gas can flows into the device for 24 hours. Moreover, at operating of gas scrubber, the amount of electricity consumption is 5 kWh. At Standby of gas scrubber, it spends 3kwh. It is certain that the energy consumption is greater at operating mode than at standby mode. The carbon emission rates from 24 hour gas scrubber operation are 236 $kgCO_2$/day of $N_2$, 57 $kgCO_2$/day of electric power and 0.001 $kgCO_2$/day of cooling water. Most of carbon is emitted from $N_2$ gas and electric power consumption.

• 한국멀티미디어학회논문지
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• 제10권2호
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• pp.260-268
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• 2007

현재의 컴퓨터 및 모바일 분야의 게임 개발은 C/C++ 언어와 DirectX를 사용한 게임 개발을 주로 하고 있다. 하지만 이러한 제한된 개발 언어의 사용은 여러 유형의 게임 엔진 제작에 있어 게임 엔진의 다양화를 억제하는 요소가 된다. 본 논문은 제한된 게임 개발 언어의 사용을 다양화 시키는 목적으로 자바를 이용하여 게임을 개발하고자 하였다. 특히 자바의 특징 중 코드의 재사용성을 이용하여 게임 엔진에서의 코드 재사용과 확장성을 고려한 게임으로 비행기 전투 게임인 메타버스 게임 엔진을 설계하고 개발하였다.