• BMB Reports
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• 제40권2호
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• pp.151-155
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• 2007

An International Symposium on Epigenomics took place at Yonsei University, Korea in December, 2006. The meeting brought to light new aspects of genome regulation by DNA and protein modification.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.842-846
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• 1997

Micro-hole drilling (holes less than 0.5 mm in diameter with aspect ratios larger than 10) is gaining increased attention in a wide spectrum of precision production industries. Alternative methods such as EDM, laser drilling, etc. can sometimes replace mechanical micro-hole drilling but are not acceptable in PCB manufacture because they yield inferior hole quality and accuracy. The major difficulties in micro-hold drilling are related to wandering motions during the inlet stage, high aspect ratios, high temperature,etc. However, of all the difficulties, the most undesirable one is the increase of drilling force as the drill penetrates deeper into hold. This is caused mainly by chip related effects. Peck-drilling is thus widely used for deep hole drilling despite the fact that it leads to low productivity. Therefore, in this paper, a method of cutting force regulation is proposed to achieve continuous drilling. A proportional plus derivative (PD) and a sliding modecontrol algorithm will be implemented for controlling the spinle rotational frequeency. Experimental results will show that sliding mode control reduces the nominal cutting force and its variation better than the PD control, resulting in a number of advantages such as an increase in drill life, fast stabilization of the wandering motion, and precise positioning of the hole.

• 한국정보통신학회논문지
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• 제13권2호
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• pp.207-214
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• 2009

본 연구에서는 결합상품 서비스 제공에 대한 경제적 이론을 분석한다. 먼저, 번들링의 부정 적 측면을 강조한 연구에 대해 분석한다. 그 다음에는 번들링의 경쟁중립적 효과에 대한 연구를 분석한다. 이는 번들링의 부정적 측면에 대한 반박이라 할 수 있다. 그 다음에는 번들링에 영향을 주는 주요 상환들을 정리하고 각 상황하에서 번들링의 제반 효과에 대해 분석한다. 번들링은 경쟁기업을 저지함으로써, 사회 전체의 효율을 떨어뜨리기는 하지만, 어떠한 경우에는 경쟁을 저지하는 역할을 수행하지 않고 오히려 후생을 증대시키는 역할도 한다. 마지막으로 순수번들링에 대한 허가기준, 동등접속의 요건 설정, 결합요금규제로서 할인율 제도, 사전규제와 사후규제, 그리고 요금적 정성 규제에서 약탈적 가격에 대한 기준 등 번들링에 대한 정책적 접근방안을 제시한다.

• 한국컴퓨터정보학회논문지
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• 제25권8호
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• pp.119-128
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• 2020

본 연구는 노인장기요양서비스 이용만족도에 영향을 미치는 시장특성 요인을 파악하고자 노인장기요양기관 이용자 246명을 대상으로 설문조사를 실시하였다. 수집된 자료는 SPSS 23.0 통계프로그램을 이용하여 분석하였다. 그 결과 첫째, 유형성에는 경쟁성, 행정규제, 과정의 체계성, 선택의 자율성이 정(+)의 방향으로 유의한 영향을 미치고 있었다. 둘째, 신뢰성에는 주택소유, 경쟁성, 행정규제, 선택의 자율성이 정(+)의 방향으로 유의한 영향을 미치고 있었다. 셋째, 대응성에는 기관규모, 월용돈, 경쟁성, 행정규제, 과정의 체계성, 선택의 자율성이 정(+)의 방향으로 유의한 영향을 미치고 있었다. 넷째, 보증성에는 월용돈, 경쟁성, 행정규제, 과정의 체계성, 선택의 자율성이 정(+)의 방향으로 유의한 영향을 미치고 있었다. 다섯째, 공감성에는 경쟁성, 행정규제, 합리문화, 과정의 체계성, 선택의 자율성이 정(+)의 방향으로 유의한 영향을 미치고 있었다.

• 한국기계가공학회지
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• 제18권3호
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• pp.14-25
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• 2019

From 2019 onwards, more stringent regulations (from Stage 4 to Stage 5) are to be implemented in Europe in order to reduce the air pollutant emissions. In South Korea, the government authorities started to make new regulation to meet the European regulation. As a first step, the air pollutant emissions such as CO, NOx, SOx, TSP, $PM_{10}$, $PM_{2.5}$, VOC, $NH_3$ by agricultural machinery were analyzed based on CAPSS inventory along with the analysis in the general aspect in this study. Three levels of analysis was conducted each in agricultural machinery aspect along with in the general aspect. Per agricultural tractor, all kinds of the air pollutant emissions decreased by 25, 25, 99, 25, 25, 25, 25% for the CO, NOx, SOx, TSP, $PM_{10}$, VOC, $NH_3$ emissions each from the year 2000 to the year 2014. Per combine harvester, all kinds of the air pollutant emissions decreased by 63, 63, 91, 63, 63, 63, 63% for the CO, NOx, SOx, TSP, $PM_{10}$, VOC, $NH_3$ emissions each from the year 2000 to the year 2014.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.163-168
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• 2005

In case of rolling stock, SEMS is generally applied in the advanced countries, but is start stage in our country. SEMS is defined the system engineering management system in order to achieve the optimized train performance among the several client requirements aspect of technical engineering management during the design life cycle. And the fire engineering activities in hong kong EMU project are introduced aspect of SEMS in this paper. The fire engineering at rolling stock in view of SEMS controls to apply the satisfied interior material by the fire safety standards (regulation of the commute urban subway safety guideline by the MOCT, BS 6853, NFPA 130, NF F 16-101) and to minimize the fire load in order that passengers egress safe from the fired rolling stock. The rolling stock in the advanced countries is designed to stand for 15-20 minutes in considering the rolling stock to be fired in tunnel. For passenger fire safety, the passenger evacuation provision and progress is set up.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2005년도 제12회 학술대회 논문초록
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• pp.94-94
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• 2005

• 한국정밀공학회지
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• 제15권1호
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• pp.117-129
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• 1998

Micro-hole drilling (holes less than 0.5 mm in diameter with aspect ratio larger than 10) is recently having more attention in a wide spectrum of precision production industries. Alternative methods such as EDM. laser drilling, etc. can sometimes replace the mechanical micro-hole drilling but are not acceptable in PCB manufacture because of the inferior hole quality and accuracy. The major difficulties in micro-hole drilling are related to small signal to noise ratios, wandering motions of the inlet stage, high aspect ratios, high temperatures and so forth. Of all the difficulties. the most undesirable one is the increase of drilling force as the drill proceeds deeper into the hole. This is caused mainly from the chip effects. Peck-drilling is thus widely used for deep hole drilling despite that it suffers from low productivity. In the paper, a method of cutting force regulation is proposed to achieve continuous drilling. A PD and a sliding mode control algorithms were implemented through controlling the spindle rotating frequency. Experimental results show that the sliding mode control reduces the nominal cutting force and the variation of the cutting force better than the PD control. The advantages of the regulation, such as increase of drill life, fast stabilization of a wandering motion, and the precise positioning of the hole are verified in experiment.

• 한국주거학회논문집
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• 제13권5호
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• pp.89-99
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• 2002

The multifamily housing has various advantages in construction cost, land-use intensity. KRIHS(1997) recommended the proper scale of th multifamily housing as 800 households in constructability, 1,000 households in facility compactability, 500 households in social aspect. At the early planning stage of project, the size of the multiftmily housing has, until now, been maximizingly considered under the regulation on which has been emphasized at the building volume ratio, land area, etc., except for the expenditure during the maintenance stage. This paper aimed at providing the proper size of multifamily housing in aspect of area and household number with maintenance cost at the early stage of project. For these, it took 곧 average cost function which is made from the 3-rd quardratic form and analyzes the unit increasing rate of the average cost. It surveyed in nationwide focused on the central heating system using diesel and kerosene. The number of samples is 88 and items of management cost is 11. The results are as follows ; first, 3rd-order quadratic function is proper at explaining the cost variation, considering the multicollinearity and statistics. Second, the proper size of multifamily housing is recommended with 83,000 $m^2$ on management area, 820 or over the 2,630 household number in aspect of total management cost.

• Journal of Periodontal and Implant Science
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• 제43권6호
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• pp.262-268
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• 2013

The use of dental implants has become a mainstay of rehabilitative and restorative dentistry. With an impressive clinical success rate, there remain a few minor clinical issues with the use of implants such as peri-implant mucositis and peri-implantitis. The use of laser technology with implants has a fascinating breadth of applications, beginning from their precision manufacturing to clinical uses for surgical site preparation, reducing pain and inflammation, and promoting osseointegration and tissue regeneration. This latter aspect is the focus of this review, which outlines various studies of implants and laser therapy in animal models. The use of low level light therapy or photobiomodulation has demonstrated its efficacy in these studies. Besides more research studies to understand its molecular mechanisms, significant efforts are needed to standardize the clinical dosing and delivery protocols for laser therapy to ensure the maximal efficacy and safety of this potent clinical tool for photobiomodulation.