• 한국기계가공학회지
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• 제11권2호
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• pp.152-158
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• 2012

A newly developed attachment type high-speed spindle can be easily attached to the conventional CNC machining center to allow high-speed machining with low investment costs. This study has focused on the application of a conventional CNC machining center equipped with an attachment type high-speed spindle. A specimen of plastic mold material has been machined to compare the cutting effectiveness of the high-speed machining center and the conventional machining center with the attachment type high-speed spindle respectively. The rotational accuracy of the spindles are measured by a transmission optic measurement system and the surface roughness of the workpiece in accordance with revolution speed(rpm) of the spindle are investigated respectively. As the experimental results, it was shown that the surface roughness of the machined workpiece was $3.42{\mu}mR_{max}$, $0.46{\mu}mR_a$ in the case of attachment type spindle and $1.81{\mu}mR_{max}$, $0.275{\mu}mR_a$ in the case of the high-speed machining center. Moreover, the mean rotational accuracy was $7.57{\mu}m$ in the case of the attachment type spindle and $7.39{\mu}m$ in the case of the high-speed machining center.

• 한국건축시공학회지
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• 제10권3호
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• pp.91-97
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• 2010

현재 건물 부력에 대한 보호조치로 경제성 및 효율성 측면을 고려하여 영구배수 공법의 사용이 증가하고 있다. 영구배수공법은 건축물에 접하는 지하수를 외부로 배수시켜 건축물에 작용하는 부력을 근본적으로 제거하는 공법으로, 영구배수공법 사용시 유출지하수가 발생하게 된다. 또한 우리나라는 국제인구행동연구소(PAI)에서 지정한 물 부족 국가로 지정되어 유출지하수의 활용이 요구되고 있지만 이에 대한 평가프로세스가 아직 충분하지 않다. 따라서 본 연구는 현장 적용 사례를 통해 현장 단위에서 유출되는 지하수의 활용여부를 결정할 수 있는 평가 프로세스를 구축하고 경제성을 분석하였다. 그 결과 상수도와 비교한 10년간 상수절감 비용을 통해 유출지하수의 활용이 가능한 것으로 나타났다.

• 유통과학연구
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• 제17권9호
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• pp.117-125
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• 2019

Purpose - We investigate how to increase consumer incentives to buy public offering funds, resulting in activating the public offering fund market. In particular, this study aims to find ways to expand diversity and to improve efficiency of public offering fund. The public fund market of Korea has been stagnant in recent years. However, the public offering fund market plays a very significant role in terms of consumer welfare. Since only a few wealthy investors can participate in the private equity market, the stagnation in the public offering fund market usually reduces the opportunity of consumer's buying funds thus ultimately affecting their future wealth. Research design, data, and methodology - To attain our purpose, the 'factor-based portfolio strategy' has been considered. It is an alternative portfolio strategy, which composites the advantages of the passive management and active management. For our empirical anaylsis, we used global stock distribution market data over the period of 1991 and 2016. Then we constructed portfolios based on firm-size, firm-value, and momentum. Finally, a regression model was set, then hypotheses were tested, analyzing the performances. Results - First, among the 15 factor-based portfolios of global, Europe, Asia-Pacific(ex Japan), US and Japan, in eight portfolios, positive excess returns are observed at 5% significance level. Further, there is another portfolio with positive excess return at 10% significance level. Second, most of the portfolios with significant excess performance show positive relationship with the market portfolio. However, the firm-value based portfolio in Asia-Pacific region shows no relationship, and the firm-value based portfolio in US shows negative relationship. Third, we confirmed that the two firm-value factor portfolios in Asia-Pacific region and US, not having positive relationship with market portfolio, provide significant excess returns. Conclusions - In this paper, we provide empirical evidences supporting that the factor-based portfolios expand the diversity of funds and improve the efficiency of investment performance. However, there is no guarantee that the efficiency will continue in the future. In addition, various constraints and costs must be considered. Nevertheless, our novel findings in the advanced financial market such as US and Asia-Pacific are very interesting and offers important implications.

• Journal of Biosystems Engineering
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• 제35권2호
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• pp.91-99
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• 2010

A Model of small scale total mixed rations(TMR) plant which can be utilized round bales was developed, tested and analyzed in this study. This study consist of two parts. One is development of a small scale TMR plant model which was already reported at the previous paper. This is the second part of the study. For the study, a series of tests of the model plant were performed and its costs was analyzed. Also, the break-even point of the model plant by comparing with market price of commercial TMR feed was determined. Results of the research are summarized as follows ; As the results of mixing test, the average coefficient of variation(CV) value for mixing of the feed was 13.0 % at the gate of the mixer. The production cost was estimated as 8,298 won/head for dairy cattle farm and 2,495 won/head for beef cattle farm, when producing 8 batch a day. Also, it is recommended to utilize the model plant when farm size is over 79 heads for dairy cattle farm and 113 heads for beef cattle farm. As an overall conclusion, the model plant designed for farm size TMR feed mill will be very useful model for both beef cattle and dairy farms in Korea. Also it is expected that the capital investment for the model plant can be recovered with 8 months compare with purchasing commercial TMR feed if the model plant feeds 1,000 beef cattle approximately.

• 농촌계획
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• 제19권4호
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• pp.73-79
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• 2013

As facilities performing the production, processing, preservation, and shipment of agricultural products; agricultural facilities are categorized into planting facilities and livestock facilities based on the management target. Agricultural facilities are set in farmlands, and facility users mainly complain about the legal or institutional restrictions on farm rather than their own facilities itself. From 2009 to 2012, the Ministry of Agriculture Food and Rural Affairs (MAFRA) published the "Casebook of farmer Complaints on Farmlands" in order to help answer farmers' questions and support public workers' workloads. However, contents related to agricultural facility installed in farmland are currently not dealt with in particular. Among agricultural facilities, demands of property rights with livestock facilities have risen due to construction permissions, operational restrictions, and high initial investment costs; and relevant laws were revised and are now being executed. However, for planting facilities such as mushroom facilities, ginseng facilities, and greenhouses; farmer complaints related to property rights are constantly increasing because revisions to relevant laws are not being made despite the rising diversity of construction materials through technical developments as well as the rising scale of assets-i.e. mechanization, automation, and the application of New Regeneration Energies according to capital influx. In this study, the current state of relevant agricultural facility legislation were organized and their drawbacks deduced in order to propose improvements of Agricultural Facility Legislation. The result of interviewing with public workers and farmers show that agricultural facilities should be regarded as extensions of farmlands rather than as facilities built in land where development actions were being taken. Alternatives able to reflect these opinions were suggested through expert consultation.

• 한국통신학회논문지
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• 제27권11C호
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• pp.1178-1188
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• 2002

LLU는 신규사업자의 시내서비스 진입장벽을 낮춤으로써 음성서비스 및 광대역서비스 제공에 경쟁을 촉진할 수 있으며, 시내망 부문의 사업자간 중복투자를 방지한다는 긍정적인 측면이 있다. 그렇지만, LLU의 도입은 시내망 부문의 설비기반 경쟁을 감소시키고, 새로운 정책의 도입에 따른 직접비용과 규제비용을 발생시킨다는 점에서 부정적인 측면도 함께 공존하고 있다. 따라서 전반적인 LLU의 경제적 효과는 해당국가의 특수한 상황 및 LLU의 목적에 따라 다르게 나타날 것이다. 본 연구에 의하면 EU의 경우 대다수 회원국이 LLU를 도입하여 이미 시행하고 있으나 현재 LLU의 도입 초기에 예상했던 경제적 효과들은 기대하기 어려운 상황이다. LLU의 원활한 시행이 이루어지기 위해서는 규제문제, 합리적인 LLU 제공대가의 수준, 기술적·운영적 문제 등 LLU의 시행과정에서 발생되는 주요 이슈에 대한 신중한 검토가 요구된다.

• 한국측량학회지
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• 제9권2호
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• pp.57-66
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• 1991

본 연구는 우리나라 측량제도를 측량사 제도, 측량업 제도, 측량 용역비 제도로 구분하여 현제도의 실태를 파악하고 그 문제점을 도출하여 측량제도의 개선 방안을 제시하였다. 측량사 제도는 우리나라 측량제도와 유사한 조건에 있는 아시아권을 중심으로 외국제도를 우리나라 제도와 비교 분석하였으며, 또한, 측량업 제도 및 측량용역비 제도에서는 외국의 측량업계 현황과 우리나라의 기술용역육성법에 의한 기술용역업 제도 및 건축사법에 의한 건축사 제도를 중심으로 비교 연구하였다. 본 연구 결과 측량제도의 개선을 위해서는 측량기술의 고급화, 고급 측량사의 확보, 교육 및 연구시설의 확충과 측량용역업체의 활성화가 요구됨을 알 수 있으며, 이에 대한 대안으로 정부당국의 정책적인 지원과 측량법의 개정으로 중규모 측량업체 육성, 지방자치제에 따른 수도권에 편중된 측량업체의 지방분산화 방안을 제시하였다. 또한, 측량업체의 영세성 및 측량인력 확보에 관한 측량용역비 개선 방안으로 측량비 구성기준 제시, 측량기술자 등급 조정 및 간접비 요율의 산정을 통한 효과적인 용역비 산정제도를 제시하였다.

• 한국유기농업학회지
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• 제20권3호
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• pp.267-282
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• 2012

In this study, RPS system, one of the renewable energy support systems, is utilized for economic analysis of solar generation equipment and the fuel cost savings plan for controlled horticulture farms with high fuel-cost dependency and facility applicability were evaluated. On the exterior of the upper layer of glass greenhouse (9917$m^2$) of controlled horticulture farms using bunker C oil, half of the area (4958$m^2$) was utilized for theoretical installation and operation of 450kW-level solar power generator, and as the result, first, the effect of investment cost only of solar generation system was found to be quite excellent, but it was analyzed that there were limits to saving the fuel costs of the controlled horticulture farms. Second, when geothermal system was first introduced in the farm and solar system was additionally introduced, it was analyzed that the effect of introducing solar system was excellent. In order to apply such effects to the sites of farming, partial supplementation of RPS system which is being uniformly applied regardless of the purpose of renewable energy is necessary. When the subject of use directly install facilities where it is directly connected to national added-value such as food security created by the farming industry, it is necessary to introduce appropriate system that corresponds to such. Moreover, it was studied that the quick development of demonstrative complex that can practically evaluate the applicability of renewable energy in farming industry and interest and preparation of related institutions in financial support structure for its site application would lead to success.

• 한국병원경영학회지
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• 제22권2호
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• pp.44-57
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• 2017

The objective of this study is to investigate financial integrity strategies for sustainable development of local public medical centers, and particularly focus on seeking ways to enhance its financial efficiency and publicness. The data which was collected from 33 local public medical centers was analyzed by Data Envelopment Analysis to measure its financial efficiency. Then, Matrix Analysis was used to examine the association of financial efficiency and publicness of local public medical centers with related factors. In the aspects of facilities and location, according to the results, the local public medical centers which have larger number of available hospital beds or located in bigger cities were examined to have higher degree of publicness. In the aspect of human resources, greater number of doctors made both financial efficiency and the degree of publicness decreased, whereas higher participation rate of educational program for doctors affects increasing its financial efficiency and publicness. Lastly, in the aspect of costs, higher labor, material, and administrative cost diminished financial efficiency, but enhanced the degree of publicness. Based on these results, this study concluded that enhancing the publicness of local public medical centers should be pursued by increasing the accessibility with better facilities and location, and also concurrently organizing rational expenditure structure with appropriate cost investment to the resources of local public medical centers. Also, it is necessary to enhance both financial efficiency and publicness simultaneously by improving the quality of health care services through the educational programs for medical staffs.

• 한국수자원학회논문집
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• 제30권4호
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• pp.367-377
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• 1997

수량과 수질 양면에서의 '물위기'를 극복하 수 있는 공공정책 개발을 위해 두 가지 접근방법으로 수도사업의 국민경제적 역할을 고찰하고자 했다. 먼저 급속한 산업화와 도시화로 인해 물소비가 급증한 시기인 1978-1994년 동안의 물소비와 경제성장간의 관계를 살펴보았다. 물의 총수요와 부문별 수요의 가격 및 소득탄력성을 분석하였다. 둘째, 단기적으로 수자원 문제를 분석할 수 있는 투입-산출(I-O, input-output)모형을 개발하였다. 통상적인 I-O 모형을 고찰한 뿐만 아니라 그 응용으로서 i) 공급유도 투입-산출모형을 이용한 부문별 공급지장비용 평가와, ii) 레온디에프 가격모형을 이용한 수도요금 상승으로 인한 부문별 물가파급효과분석을 다루었다. 결론적으로 가장 주목할 만한 정책적 시사점은 수도부문에 대한 트자와 물공급장애가 생활수준과 산업생산에 큰 영향을 미치지만, 절수를 고무하고 투자재원을 확보할 목적의 수도요금 인상은 물수요를 유의하게 감소시키지만 전반적 물가수준에 별다른 영향을 미치지 않는 것으로 나타났다.