• 대한전자공학회논문지SD
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• 제41권6호
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• pp.43-51
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• 2004

본 논문에서는 입력패턴을 triple rail-coding 방식으로 표현한 후 입력의 직렬연결 방법으로 기호치환을 수행하는 광 병렬 변형부호화자리수 가산 시스템을 제안하였다. Triple rail-coding 방식으로 변형부호화자리수 입력을 표현할 때 중복연산 결과가 나오는 입력들은 동일한 패턴으로 전처리하여 기호치환과정의 규칙수를 줄였고, 광 구현시 공간 이동된 입력패턴을 직렬로 연결하여 광을 통과시킴으로써 공간 이동 연산, NOR 연산, 그리고 문턱치 연산과정이 필요 없는 광 가산기를 구현하였다.

• KIEE International Transactions on Power Engineering
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• 제5A권1호
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• pp.9-15
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• 2005

In the operation of distribution systems, DGs (Distributed Generations) are installed as an alternative to extension and the establishment of substations, transmission and distribution lines according to the increasing power demand. In the operation planning of DGs, determining optimal capacity and allocation achieves economical profitability and improves the reliability of power distribution systems. This paper proposes a determining method for the optimal number, size and allocation of DGs in order to minimize the operation costs of distribution systems. Capacity and allocation of DGs for economical operation planning duration are determined to minimize total cost composed with power buying cost, operation cost of DGs, loss cost and outage cost using the GA (Genetic Algorithm).

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.151-156
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• 2003

The Communication Based Train Control(CBTC) System generally used to improving existing lines in the world is efficient and stable for improvement. Also it is efficient for improvement because it does not cause any problems in operation of existing lines. We examined the mixed operation scheme for more efficient and stable improvement when improvement is implemented depending on aged equipment and the increased number of passengers in the Korean city railroad. The biggest point in the mixed operation is to implement a stable test without interfering with the operation of the existing lines. For this purpose, we deduced a method of installing the equipment, a method of testing depending on the installed equipment, and the types of mixed operation, and presented a scheme of execution of the methods depending on the mixed operation.

• 전자공학회논문지 IE
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• 제44권3호
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• pp.12-22
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• 2007

본 논문에서는 잉여수체계(Residue Number System)를 이용하여 고속의 디지털 신경회로망을 제안하고 이를 구현하기 위한 중요연산부인 고속의 디지털 뉴런프로세서를 설계하였다. 설계된 디지털 뉴런프로세서는 잉여수계를 이용한 MAC 연산기와 혼합계수 변환을 이용한 시그모이드 함수 연산 부로 구성되며, 설계된 회로는 VHDL로 기술하였고 Compass 툴로 합성하였다. 실험결과, 본 논문에서 설계한 디지털 뉴런프로세서는 19.2nsec의 속도를 보였으며, 실수연산기로 설계한 뉴런프로세서에 비하여 약 50%정도 하드웨어 크기를 줄일 수 있었다. 본 논문에서 설계한 뉴런프로세서는 실시간 처리를 요하는 병렬분산처리 시스템에 적용될 수 있을 것으로 기대된다.

• 한국수학교육학회지시리즈A:수학교육
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• 제51권1호
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• pp.1-19
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• 2012

In this study, contents of 'the 2007 revised curriculum handbook' and 16 kinds of mathematics textbooks were analyzed first. The purpose of this study is to examine the understanding state of students at general high schools by making questionnaires to survey the understanding state on contents of chapter of complex number based on above analysis. Results of research can be summarized as follows. First, the content of chapter of complex number in textbook was not logically organized. In the introduction of imaginary number unit, two kinds of marks were presented without any reason and it has led to two kinds of notation of negative square root. There was no explanation of difference between delimiter symbol and operator symbol at all. The concepts were presented as definition without logical explanations. Second, students who learned with textbook in which problems were pointed out above did not have concept of complex number for granted, and recognized it as expansion of operation of set of real numbers. It meant that they were confused of operation of complex numbers and did not form the image about number system itself of complex number. Implications from this study can be obtained as follows. First, as we came over to the 7th curriculum, the contents of chapter of complex number were too abbreviated to have the logical configuration of chapter in order to remove the burden for learning. Therefore, the quantitative expansion and logical configuration fit to the level for high school students corresponding to the formal operating stage are required for correct configuration of contents of chapter. Second, teachers realize the importance of chapter of complex number and reconstruct the contents of chapter to let students think conceptually and logically.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 학술대회 논문집
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• pp.237-240
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• 2004

For the paralleled operation of DC/DC converters, the current sharing between each modules is the most important for the reliability of the power system. Interleaving method is commonly used with many paralleling schemes for the reduction of the ripple in the output voltage of paralleled converters and there are many commercial IC for interleaving application appliable. But for all of them, it is impossible to detect the number of module in operating and then change the phase of them automatically. In this paper, a novel paralleling method is proposed for the converter parallel operation, which detects the number of modules in active and sets the phases of PWM signals applied to each modules autonomously. This can greatly improve the output voltage ripple and reliability of the system. The expandibility of modular number can be done very easily by just adding several parts.

• 대한간호학회지
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• 제2권1호
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• pp.49-61
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• 1971

The purpose of this study is to observe the administering of analgesics and sedatives to cases of surgery, the influence of the patients'situational variables on the use of these drugs, and the required number of recovery days in relation to the patients'situational variables and general conditions. Fifty patients in the age range of 15 through 65 who had undergone general surgery at Seoul national University Hospital. Woo Sok University Hospital and Koryo Hospital between May and August of 1971 were chosen for this study. They were observed with regard to the frequency of postoperative uses of analgesics and sedatives age, the required period of recovery in comparison with the situational variables of patients such as sex, age, marital status, the type and duration of anesthesia, experience of previous operation, history of other diseases, preoperative period of hospitalizations and the general conditions of patients such as sleep, stomach condition, bowel condition, urination, interest in surroundings, strength and energy, self-assistance and appetite. The study results were reviewed in a statistical method to obtain the following findings: 1. There was a significant decrease in the frequency of analgesic uses according to the number of days passed after operation. 2. The mean postoperative recovery days were 5.31 days and mote than half of the patients have never used analgesics until recovery. 3. There was a significant decrease in the frequency of sedative uses according to the number of days passed after operation. 4. The rank-order correlation between the frequency of analgesic use and that of sedative use following surgery observes in relation to the number of postoperative days was a low and negative one. 5. All of the patients except one hate used sedatives only once a day for the whole recovery period. 6. The longer they stayed in the hospital before surgery, the less have they used analgesics after surgery. 7. There were significant differences in use of analgesics after surgery by age groups; the 25-44 age group used more analgesics than the 15-24 and 45-65 age groups. 8. There were no significant differences in use of analgesics after surgery by all situational variables except the number of days of hospitalization and age. 9. The longer they stayed in the hospital before surgery, the earlier have they recovered from the surgery. 10. There were no significant differences in the number of required recovery days by all situational variables except the length of preoperative hospitalization. 11. There were no significant differences in the number of required postoperative recordedly days by the general conditions of patients.

• 대한산업공학회지
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• 제18권1호
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• pp.155-167
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• 1992

This paper presents an automatic setup planning system for turning operation of symmetric rotational parts. The proposed setup planning system determines workpiece holding method, number of setup, clamping surface, and workpiece holding device by using design data, part description database and part feature recognition information. The workpiece holding method is based on functional name and length/diameter ratio of the given part, and number of setup is determined by part profile type and its technological constraints. Clamping surface and workpiece holding device are determined by using information about the results of workpiece holding method and number of setup, and capacity of workpiece holding devices. A case study is performed to show the performance of the proposed system.

• 대한교통학회지
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• 제30권2호
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• pp.21-27
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• 2012

이 연구는 신호교차로의 신호운영과 교통사고의 관계를 다루고 있다. 연구의 목적은 전적색신호시간(ARCI) 운영에 따른 교통사고 감소효과를 분석하는데 있다. 이를 위해 이 연구는 청주시 37개 신호교차로를 대상으로 비교그룹 방법을 사용하여 ARCI의 교통사고 감소효과를 평가하는데 중점을 두고 있다. 주요 결과는 다음과 같다. 첫째, 교통사고 건수와 사상자 수는 ARCI 도입 전 후가 다른 것으로 평가되었다. 둘째, 교통사고 감소효과를 비교그룹방법으로 분석한 결과, 사고건수는 20.0%, 그리고 사상자 수는 28.0% 감소한 것으로 분석되었다. 마지막으로, 전적색신호시간 운영에 따른 사고건수의 감소 효과는 6.0~35.0%, 사상자 수의 감소 효과는 18.0~37.0%로 평가되었다.

• 대한안전경영과학회지
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• 제10권3호
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• pp.99-107
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• 2008

Product liability(PL) is the producer's compensation to customers for damage incurred by product defects. This paper studies on the organizational culture, promotion process, system construction, system level, product safety review, product safety assurance, system operation, and its effectiveness and necessity of recognition for the PL system of small and medium-sized firms in Gangwon-Do province. The results show that the firms have product safety regulations, but the number of firms which its employees understand the regulations is less than the number of firms which do not understand. Also the number of firms which is preparing PL prevention and insurance, and counterplan for accidents seems to be not in large numbers.