• 마이크로전자및패키징학회지
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• 제18권1호
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• pp.41-47
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• 2011

Currently, there is widespread adoption of silicon-based technologies for the implementation of radio frequency (RF) integrated passive devices (IPDs) because of their low-cost, small footprint and high performance. Also, the need for high speed data transmission and reception coupled with the ever increasing demand for mobility in consumer devices has generated a great interest in low cost devices with smaller form-factors. The UWB BPF makes use of lumped IPD technology on a silicon substrate CSMP (Chip Scale Module Package). In this paper, this filter shows 2.0 dB insertion loss and 15 dB return loss from 7.0 GHz to 9.0 GHz. To the best of our knowledge, the UWB band-pass-filter developed in this paper has the smallest size ($1.4\;mm{\times}1.2\;mm{\times}0.40\;mm$) while achieving equivalent electrical performance.

• Advances in Energy Research
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• 제5권3호
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• pp.207-217
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• 2017

Energy consumption in agriculture is responsible for greenhouse gas emission but it can be reduced after efficient utilization of energy inputs. Therefore, the present study aims for the estimation of energy efficiency and extent of greenhouse gas reduction after benchmarking of inefficient farms in off-season tomato in Punjab province of Pakistan. Primary data were collected from 70 farmers with simple random sampling. By using data envelopment analysis, the average value of technical, pure technical and scale efficiency was 0.80, 0.92 and 0.87, respectively while increasing, constant and decreasing return to scale was observed in 33, 26 and 11 farmers, respectively. Total input energy was reduced by $12,688.91MJ\;ha^{-1}$ (13.89%) if inefficient farms used the energy inputs according to recommendations or benchmarking. A major portion of energy saving comes from fertilizers (68.79%) followed by diesel (15.70%), chemicals (5.91%), machinery (4.37%) and water (4.00%). Total greenhouse gases reduction was $499.17kg\;CO_2\;eq.ha^{-1}$ (14.57%) as a result of improvement in energy efficiency or benchmarking of inefficient farms. Agricultural extension staff should visit the vegetable farms on regular basis and give necessary information about efficient utilization of energy inputs. The government should create awareness about the optimum use of input through seminars and pamphlets.

• 한국콘텐츠학회논문지
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• 제19권8호
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• pp.151-158
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• 2019

국내 전기 전자 산업이 보유하고 있는 높은 기술력은 국외 시장에서도 인정받고 있지만 현재 주변국과의 기술경쟁 등이 갈수록 심화되어져 가고 있는 상황이다. 따라서 이들 기업들이 경쟁우위를 차지하기 위해서는 무엇보다 운영상의 비효율성을 재정비하여 효율적인 생산 활동을 실시하여야한다. 이에 본 논문에서는 DEA 기업을 통해 국내 고성장 전기 전자사업의 경영효율성을 분석하며 비효율적인 기업의 투사값을 제시하며 벤치마킹의 대상이 될 수 있는 기업들의 참조집합을 확인하고자 한다. 이를 위해 총 20개 고성장 전기 전자기업들의 CCR와 BCC모형의 효율성과 규모수익성(RTS)을 분석하였다. 분석결과 BCC 효율성이 1인 기업은 총 12개, CCR 효율성이 1인 기업은 총 4개 기업으로 나타났다. 그리고 BCC, CCR 효율성이 모두 1인 기업은 총 4개 기업이었다. 또한 기업의 규모수익성은 IRS가 11개 기업, CRS가 6개 기업 그리고 DRS가 3개 기업으로 분석되었으며 참조빈도 분석에서는 BCC모형에서는 4개 기업과 CCR 모형을 통해 4개 기업을 벤치마킹이 할 수 있는 기업으로 제시하였다. 이러한 결과는 동종 산업의 후발 기업들에게 기업의 운영환경을 개선할 수 있는 유용한 정보가 될 것이다.

• 한국비블리아학회지
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• 제22권4호
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• pp.301-315
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• 2011

DEA(Data Envelopment Analysis) 기법은 단위가 서로 다른 다수의 투입과 산출요소를 포함하는 기관의 상대적 효율성 평가에 유용하다. 그래서 본 연구는 29개 대학 도서관을 대상으로 상대적인 경영 효율성을 측정하고자 DEA의 CCR모형과 BCC모형을 적용하여 기술효율성(TE), 순수기술효율성(PTE), 규모효율성(SE)을 분석하였다. 투입요소로는 도서수, 자료구입비, 면적, 직원수, 자료실 좌석수가 사용되었고 산출요소로는 대출자수, 대출권수, 도서관 방문자수가 사용되었다. 분석결과 13개의 대학도서관이 효율적인 것으로 나타났고 비효율적인 대학도서관의 원인은 순수기술비효율 보다 규모비효율의 비중이 더 큰 것으로 파악되었다. 비효율적인 도서관의 규모의 수익효과는 대부분의 도서관이 규모의 수익체증 유형인 것으로 나타났다.

• 농촌지도와개발
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• 제9권2호
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• pp.263-277
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• 2002

The objective of this study was to compare the farm efficiency of members of cooperative firms with that of non-members in Korea. Data were collected from 27 farms members of three cooperatives and 13 non-member farms, based on the managerial achievements of 1999. For the analysis, the data were divided into three different farming types: type I and II of member farms and non-member farms. Economic analysis were implemented using DEA(Data Envelopment Analysis). Major findings was as follows. Total average technology efficiency was 0.782, which implies that there still remains 21.8% of improvement possibility. Among the three types, type I showed the highest technology efficiency of 0.9055, while type II and non-member farms showed 0.7670 and 0.7171, respectively. This means that these farms have relatively high potential improved. Also, comparing technology efficiency by dividing into pure technology and scale efficiency, all type of the farms exhibit a higher pure technology efficiency compared to scale efficiency. Therefore, to improve current technology efficiency, farms need to focus more on pure technology efficiency improvement. Meanwhile, profit analysis based on farm size indicate that most of the farms demonstrated the increasing-return-to-scale, which means it is necessary to extend the farm size to improve technical efficiency. Type I member farms achieve higher profit and efficiency than other two types and relatively higher producer prices through introducing cooperative sorting, grading and packing. Also, these labor saving technologies increased farm size.

• 자원ㆍ환경경제연구
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• 제28권3호
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• pp.415-435
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• 2019

본 연구의 목적은 중서부태평양(WCPFC) 수역 우리나라 원양연승어업의 눈다랑어 생산함수를 추정하여 규모 수익을 분석하는 것이다. 분석에 있어 투입요소는 선원수, 선박톤수, 투입낚시수, 눈다랑어 자원량 그리고 산출요소는 눈다랑어 생산량으로 하는 Cobb-Douglas 형태의 생산함수를 추정하였다. 함수 추정에 앞서 투입요소 중 눈다랑어 자원량은 Bayesian State-space 모델로 추정하였다. 생산함수 추정 결과, 하우즈만 검정을 통해 고정효과 모델이 선택되었고, 선원수를 제외한 선박톤수, 투입낚시수, 눈다랑어 자원량이 눈다랑어 생산량에 직접적인 영향을 미치는 것으로 나타났다. 추정된 생산함수의 투입요소를 바탕으로 규모 수익 수준을 분석한 결과, WCPFC 수역에서 눈다랑어를 조업하는 원양연승어업은 규모 수익 체증(IRS)의 성격인 것으로 추정되었다.

• 산업경영시스템학회지
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• 제42권2호
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• pp.62-68
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• 2019

The growth and employment effects of R&D investment were analyzed according to business size, export value and manufacturing sectors so as to suggest improvement directions for effective industry policies. The effect of R&D investment was considered simultaneously from the two perspectives of growth and employment effect, and the causality analysis was carried out by using a path analysis. The result of the path analysis confirmed significant differences in the growth effect of R&D investment depending on business size. However, the effect of increasing employment was difficult to obtain statistically significant results for any various combinations of business size and export value. This is a mixture of directions for the effects of R&D investment on employment, which could be due to the failure to consider appropriate time lags between investment and effect. Efficiency analysis by industry sectors confirmed significant differences in efficiency depending on business size, but differences depending on export value were difficult to identify. In order to derive improvement policy by industry sector according to business size and export value, the direction of selective support policy and universal support policy was derived for six industry groups by combining the return to scale in the efficiency analysis and R&D concentration. Hirschman-Herfindahl index is used for calculating R&D concentration.

• 수산경영론집
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• 제29권2호
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• pp.143-161
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• 1998

The objective of this study is to analyze the effects of increase in the oyster hatchery on fishermen's income. The results of the analysis are as follows : \circled1 The necessary quantities of oyster seed are 18,000 thousand hanging line. The 29.4%, of that has been applied by ana-seed collection and 29.1% of that has been applied by proseed collection. The demage of oyster aquaculture business is estimated about 35 billion won or 83 billion won. \circled2 The production cost per hanging line of the oyster hatchery is 1,974 won. And if it is sold by 2,500 won, return on investment will be 31.9%. Therefore profitability of the oyster hatchery is very good. \circled3 There are four important determinant variables of profitability to the oyster hatchery. In the order of their effects, it is operation number, seed price, production cost, and quantity of production. \circled4 If differences of price between the artificial hardening oyster seed and the natural hardening oyster seed are more less 1,430 won, the former is better. \circled5 The necessarily quantities of the oyster hatchery are estimated 160 units in the scale of 10,000 hanging line production to one operation. \circled6 The effect of increasing income of fishermen are estimated about 85.3 billion won or 124.5 billion won from increase in the oyster hatchery.

• 설비공학논문집
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• 제26권3호
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• pp.108-114
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• 2014

On a large scale of data center, heat generation rates from sever computers occupy almost the entire cooling load of the building, and it is gradually increasing. The efficiency of air distribution system in data centers can be affected by heat generation rates of server computers. In this study, the distributions of airflow and temperature in a data center have been investigated by CFD simulations under various conditions of heat generation rates for server computers. From the results, air around the cold aisle which has high temperature flows tremendously into the cold aisle according to the increase of heat generation rates for server computers and the air temperature in the cold aisle becomes higher. The SHI (supply heat index) and RHI (return temperature index) show almost similar values to the cases study because the air inflow rates to server computers increase with the heat generation rates of server computers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 정기총회 및 학술대회 전문대학교육위원
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• pp.157-159
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• 2008

This paper summarizes the results of these efforts by offering a photovoltaic system structure in 50kW. The combination of photovoltaic system components are interconnected and system monitoring system will be summarized for the purpose of the increasing safety in this article. This paper describes configuration of utility interactive photovoltaic system which generated electric power supplies to dormitory. In order to installing the middle or large scale photovoltaic system, It must investigated the optimal design of system, compute quantity of power generation, economic rate of return and so on. In this paper represent 50kW utility photovoltaic system examination, developed simulation results and financial analysis. The performance of photovoltaic system has been evaluated, analyzed with simulation and financial analysis results. The results obtained in this research will be much useful to prior investigation for installing utility interactive photovoltaic system.