• 대한전기학회논문지:전력기술부문A
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• 제49권10호
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• pp.494-501
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• 2000

This paper describes a strategy of a daily optimal operational scheduling in cogeneration system for paper mill. The cogeneration system selected to establish the scheduling consists of three units and several auxiliary devices. One unit generates electrical and thermal energy using the back pressure turbine. The rest two units generate the energy using the extraction condensing turbine. Three auxiliary boilers, two waste boilers and three sludge incinerators operate to supply energy to the loads with three units. The cogeneration system is able to supply enough the thermal energy to the thermal load, however it can not sufficiently supply the electrical power to the electrical load. Therefore the insufficient electric energy is compensated by buying electrical energy from utility. When the operational scheduling is performed considering the environmental problem. This paper shows the simulation results for daily operational scheduling obtained using the evolutionary algorithm. This results reveal that the proposed modeling and strategy can be effectively applied to cogeneration system for paper mill.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권8호
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• pp.360-367
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• 2002

In this paper, genetic algorithm based adaptive image enhancement filtering scheme is proposed and Implemented on FPGA board. Conventional filtering methods require a priori noise information for image enhancement. In general, if a priori information of noise is not available, heuristic intuition or time consuming recursive calculations are required for image enhancement. Contrary to the conventional filtering methods, the proposed filter system can find optimal combination of filters as well as their sequent order and parameter values adaptively to unknown noise types using structured genetic algorithms. The proposed image enhancement filter system is mainly composed of two blocks. The first block consists of genetic algorithm part and fitness evaluation part. And the second block consists of four types of filters. The first block (genetic algorithms and fitness evaluation blocks) is implemented on host computer using C code, and the second block is implemented on re-configurabe FPGA board. For gray scale control, smoothing and deblurring, four types of filters(median filter, histogram equalization filter, local enhancement filter, and 2D FIR filter) are implemented on FPGA. For evaluation, three types of noises are used and experimental results show that the Proposed scheme can generate optimal set of filters adaptively without a pioi noise information.

• 한국세라믹학회지
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• 제40권2호
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• pp.167-171
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• 2003

기계적 방법으로 합성된 CeO$_2$분말을 연마입자로 하여 STI용 CMP 슬러리를 제조하였다. 연마입자는 정전기적 방법과 입체적 방법으로 수계에서 안정화시킬 수 있었으며, 장기 안정성을 위해서는 입체적 방법에 의한 안정화가 유효하였다. 50$0^{\circ}C$와 $700^{\circ}C$에서 합성된 CeO$_2$를 이용하여 CMP 슬러리를 제조하고, SiO$_2$와 Si$_3$N$_4$가 블랭킷 형태로 증착된 웨이퍼를 연마한 결과 연마능률과 선택비는 연마입자의 합성조건과 분산 안정성, 슬러리의 pH 등에 의해 영향을 받았다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.395-396
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• 2008

There is difficulty in predicting the program efficiency of NOR type nonvolatile memory device adopting channel hot electron injection (CHEI) as program operation mechanism accurately since MOSFET on SOI has floating body. In this study, the dependence of program efficiency for SOI nonvolatile memory device of 200 nm channel length on SOI depletion conditions, partial depletion and full depletion, was quantitatively investigated with the aid of numerical device simulation [1].

• 전자공학회논문지D
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• 제36D권11호
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• pp.33-44
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• 1999

3차원 위상변이 마스크의 단차 효과를 분석하기 위해 투명 경계조건, 주기적인 경계조건, 및 연속조건을 가진 경계요소법을 광 리소그래피 공정 시뮬레이션에 새로이 적용하였으며, 해석적인 해와 참고문헌의 결과와 비교함으로써 구현된 모듈의 정확성을 검증하였다. 또한, 기존의 rigorous coupled wave analysis에 의한 방법에 비해 수렴성과 계산 시간 측면에서 경계요소법을 이용하는 것이 더 효율적임을 확인하였다. 끝으로 비교적 간단한 위상변이 마스크와 다층-위상변이 마스크에 대한 최적 설계 과정을 기술하였다.

• Toxicological Research
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• 제18권2호
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• pp.195-203
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• 2002

This study was performed to evaluate single and repeated-dose toxicities oj a new cophalosporin antibiotic agent IDC-7l81 in Sprague-Dawley rats. IDC-7181 was injected intravenously to rats at dose levels of 0, 3.2, 16, 80, 400 and 2,000 mg/kg/day for single-dose toxicity study and at dose levels of 0, 10, 50 and 250 mg/kg/day for 4-week repeated-dose toxicity study. In both studies, there were no dose-related changes in mortality clinical signs, body weight changes, food and water consumption, opthalmoscopy, organ weights, urine analysis, biochemical examination, and hematological findings of all animals treated with IDC-7l8l. Gross and histopathological findings revealed no evidence of specific toxicity related to IDC-7181. These results suggest that the intravenous maximum tolerated dose value of IDC-7181 may be over 250 mg/kg and $LD_{50}$ value may be over 2,000 mg/kg in rats.

• 동력기계공학회지
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• 제17권1호
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• pp.97-103
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• 2013

Press machine has advantages over other manufacturing machine which can produce large quantities of products in short time so it is widely used in lots of industrial sectors. To obtain the vehicle's weight lightening and rigidity of the body-frame by applying 'Hot stamping' technique is increasing in the automotive field. In this paper, to improve the irregular vibration arose by 800Ton hot stamping press, the research was continued. Bed, slide and main frame are the key part of working precision, so perform structural analysis was conducted, and based on the analyzing results, structural changes were done on the parts where structural deformation occurred.

• 한국식품영양학회지
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• 제10권3호
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• pp.325-329
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• 1997

서산 6쪽 마늘 중의 inulinase를 추출하여 황산암모늄 침전가 Sephadex G-150여과 등을 통하여 9.1%의 수율로 부분정제하였다. 부분 정제된 inulinase는 4$0^{\circ}C$와 pH 6.0에서 inulin을 가장 잘 분해시켰고 7$0^{\circ}C$ 이하와 pH 5.0~8.0에서 안정하였다. 또한 이 효소는 Al3+, Mn2+, Hg2+, Cd2+ 및 EDTA에 의하여 심하게 실활되었고 inulin에 대한 Km값은 0.22%이었다.

• 한국분무공학회지
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• 제19권4호
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• pp.216-220
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• 2014

This paper presents effect of nozzle hole number on atomization characteristic of DME fuel spray using three different type of injector having the hole number of 6, 7 and 8. For this study, PDPA(phase Doppler particle analyzer) experiment was performed in terms of $T_{ASOE}$ under various injection pressure. To compare general trend of atomization characteristic, the law data were ensemble averaged based on $T_{eng}$ of 0.2 ms. Results showed that the droplet diameter in terms of SMD(Sauter Mean Diameter) was reduced as increase in injection pressure. Increasing the number of hole lead to reduce in droplet diameter, but no significant reduction in diameter was observed between hole number of 7 and that of 8. In addition, increasing the number of hole resulted in decrease in droplet velocity which is considered as the effect of reduction in spray momentum due to decreasing of fuel quantity per each hole.

• 한국인터넷방송통신학회논문지
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• 제11권6호
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• pp.163-168
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• 2011

다수의 조명 장치를 연동하여 감성을 전파하는 시스템을 제안하고 스마트폰과 조명 장치를 기반으로 구현한다. 실제 구현 시스템에서는 스마트폰에서의 감성 전파 입력을 기반으로 다수의 LED 조명 장치를 거쳐서 다시 스마트폰으로 감성이 전달되도록 한다. 각 LED 조명 장치는 홈 네트워크와의 연동을 위해서 ZigBee를 기반으로 구현되었고, 스마트폰의 네트워크는 Bluetooth를 사용하였다. Bluetooth 와 ZigBee의 연동을 위해서 스마트폰과 연결되는 조명 장치에서는 Bluetooth와 ZigBee를 모두 사용하여 이종 네트워크 간의 데이터 연동이 가능하도록 하였다. 구현 및 실험을 통하여 제안 시스템의 효용성을 검증하였다.