• 대한전자공학회논문지
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• 제23권3호
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• pp.357-363
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• 1986

In the design of PLA's of VLSI, as the number of subsets of functions from which common preme implicants must be determined increases, the execution time increases by a factor of O(2\ulcorner. When the number of functions N is a large number, this poses a serious problem in minumization of multiple-output logic functions. In this paper a new algorithm that minimizes multiple-output logic functions is proposed. The algorithm requires less number of Fortran statements, less execution time, and less memory area than existing methods. The bases of this algorithm are explained and verified, and the sequential operation for preparation of the program is discussed.

• 한국CDE학회논문집
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• 제2권3호
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• pp.186-194
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• 1997

This paper describes new methods to minimize the cutting time in zigzag milling operation of two dimensional polygonal surfaces. Previous works have been focused on mainly experimental approaches by considering some machining parameters such as, spindle speed, depth of cut, cutter traverse rate, cutter diameter, number of teeth, tool wear, life of tool, and so on. However, in this study, we considered two geometrical factors one by one in order to see the effect separately, which are the length of cut and the number of cutter traverse. In an N-sided concave or convex polygon, an algorithm has been developed which minimize the total length of cut. Also, a heuristic approach was used to minimize the number of cutter traverse.

• International Journal of Precision Engineering and Manufacturing
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• 제8권1호
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• pp.21-26
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• 2007

In industry, multihead automatic combination weighers are used to provide accurate weights at high speed. To minimize giveaway, greater accuracy is desired, especially for valuable products. This paper describes a combination algorithm based on bit operation. The combination method is simple and saves time, since only the elements to be considered for combination are generated. The total number of combinations from which the desired output weight is chosen can be increased by extending the combination from memory hoppers to include some weighing hoppers. For an eight-channel weigher, three or four combination elements are best. In addition to targeting approximately equal amounts of products in each channel, this study investigated other schemes. Simulation results show that schemes targeting combination elements with an unequal distribution of the output weight are more accurate. The most accurate scheme involves supplying products to all memory and weighing hoppers before commencing the combination operation. However, this scheme takes more time.

• 한국항공운항학회지
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• 제18권4호
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• pp.106-112
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• 2010

After a series of aircraft noise measurements conducted in Noise Sensitive Areas(NSAs) in Gangwha Island, there appeared to be no regions affected by aircraft noise of over 75 WECPNL, the legal noise level standard for aircraft operations. However, with regard to the future environment where flight operations at Incheon International Airport are likely to escalate, an INM analysis result drawn shows that the number of regions afflicted by such noise will increase in Gangwha Island. Therefore, we studied similar cases from developed countries, which are pertinent to solutions for aircraft noise abatement in the vicinity of airports and herewith provided 6 more flight operation procedures other than those 3 currently in service at Incheon International Airport.

• 대한산업공학회지
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• 제21권4호
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• pp.555-570
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• 1995

We consider a preventive replacement policy for a cold-standby system with N components, in which only one component is in operation at a time. If the component in operation fails, a standby component is immediately switched into operation. If all components fail, the system fails. The system is inspected at random poins in time to determine whether it is to be replaced or not. If the number of failed components at the time of inspection exceeds a threshold value r, the system is replaced. Otherwise the decision is put off until the next inspection point arrives. Under the cost structure which includes a replacement cost, a system down-time cost and a holding cost of the components, we develop an efficient procedure to find the optimal control values N and r, which minimize the expected cost per unit time.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.3169-3171
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• 1999

One of the important purposes o Telecommunications power plant operation is to supply safe power for maintaining the reliable communication services. Therefore, the power plant operation support system is generally used for efficient and maintenance of power plant without the increment of the operation and maintenance staffs. To operate and maintain a number of power plants efficiently, Korea Telecom developed centralized power plant monitoring and control system. In this paper, the system feature and main functions are described.

• 수산해양교육연구
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• 제26권2호
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• pp.444-454
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• 2014

The range of optimization problem in aquaculture is very wide, resulting from the range of species, mode of operation. Quite a few studies focus marine net-cages, but studies on land based culture farm are few or no. This paper considers a allocation problem to meet production planning in land based aquaculture system. A water pool allocation model in land based aquaculture system was developed. The solution finds the value of decision variable to minimize yearly production costs that sums up the water pool usage cost and sorting cost. The model inputs were (1) the fish growth rate (2) critical standing corp (3) number of water pool (4) number of fish. The model outputs were (5) number of water pool in growing phase (6) cost of cultivation (6) optimal facility allocation(number of water pool for each growing phase). To solve the problem, an efficient heuristic algorithm based on a greedy manner is developed. Branch and bound and heuristic is evaluated through numerical examples.

• 한국가축번식학회지
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• 제9권2호
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• pp.97-104
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• 1985

This study was conducted to investigate the effects of unilateral ovariectomy on the weight of the remaining ovary, the change of number of ovarian follicle, number of corpus luteum and serum progesterone level. Sixty Sprague-Dawley female rats, 23$\pm$2 days old, were divided into 2 groups (control and unilaterally ovariectomized goup) with 30 heads per groups. Each group was again subdivided into 6 groups according to 6 experimental periods; Day 4, 8, 12, 16, 20 and 24 after uniteral ovariectomy. Five arts at every 4 day intervals were sacrificed for the measuring of ovarian weight and for quantitative histologic examination of ovary and at the same time, blood samples were taken for the determination of serum progesterone level of radioimmunoassy. The results obtained were as follows: During the experimental periods, a significant hypertrophy occured in the remaining ovary of unilaterally ovariectomized group from day 16 after operation. The average ovarian weight of control group at day 16 was 21.0$\pm$1.7mg, which is samller than that of unilaterally ovariectomized group weighing 50.5$\pm$8.4mg(P<0.01). The ovarian weight of the unilaterally ovariectomized rats at day 20 and day 24 was 75.9$\pm$2.2 mg and 63.3$\pm$7.0 mg, which is heavier than those of control group; 29.1$\pm$2.3 and 26.3$\pm$1.7 mg(P<0.01 and P<0.01). 2. A same degree of ovarian follicle development was observed in the unilaterally ovariectomized group. Following unilateral ovariectomy and there was no change in total number of follicles larger than 130$\mu$ during the period from day 4 till day 24 after operation. 3. Although the size fo ovarian follicle did not significantly change between two groups from day 4 till day 16, the size of vesicular follicle in unilaterally ovariectomized group (406.3$\pm$26.2$\mu$) was significantly greater as compared to that of control group (323.8$\pm$19.3$\mu$)(P<0.05). 4. Corpus luteum in unilaterally ovariectomized and control group began to a, pp.ar from day 16 after operation and then the number of corpus luteum slightly increased. The number of corpus luteum in unilaterally ovariectomized group at day 24 ws remarkably increased (13.7$\pm$1.41) than that of control (5.2$\pm$2.01)(P<0.01). 5. Serum progesterone levels in unilaterally ovariectomized group were slightly higher than those of control but there were no significant difference between treatment groups.

• 한국ITS학회 논문지
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• 제20권4호
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• pp.106-117
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• 2021

우리나라는 대부분의 화물 운송이 도로를 이용하여 이루어지기 때문에 화물차 군집주행에 관한 관심이 증가하고 있다. 화물차 군집주행은 연속된 두 대 이상의 화물차들이 하나의 군집을 구성해 주행하는 것으로 도로 용량의 증가와 연비를 개선할 수 있다. 본 연구에서는 화물차 군집주행이 교통류에 미치는 영향을 분석하기 위해 교통 조건, 화물차 군집주행 운영 조건에 따른 시나리오를 생성하였다. 화물차 군집주행 운영 조건의 영향이 미치는 영향을 파악하고자 평균통행속도, 차로변경방해건수, 진출입구간방해건수와 상관분석을 실시하여 결과를 도출하였다. 군집 내 화물차 수, 군집 내 화물차 간격, 군집 간 간격은 평균통행속도와 차로변경방해 건수에 영향을 미치는 것으로 나타났으며, 군집주행 화물차 비율이 LOS와 무관하게 평균통행 속도와 차로변경방해건수에 강한 연관성을 가지는 것으로 나타났다.

• 국제초고층학회논문집
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• 제6권4호
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• pp.323-326
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• 2017

Sustainability is becoming more and more important in our everyday lives. Thus, it is apparent that more sustainable initiatives are incorporated in a building design concept to reduce operation costs and environmental impacts. However, will the construction cost go up if the building is going green - especially if it is a tall building? This is the question on everyone's mind. In the following paragraphs, we will look into a case study of a skyscraper in Nanning, China. That 411-metre skyscraper, Nanning China Resources Centre East Office Tower, is currently under construction. Designed to LEED-CS Gold standards, the building has adopted a number of sustainable design elements and operation practice, which indeed only accounts for a small percentage of the total construction cost.