• 한국기계가공학회지
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• 제18권11호
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• pp.89-95
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• 2019

In this research, the effect of roughing on tool load through bottom-up machining is investigated through actual machining. Generally, through the use of high-speed machining technology, machining methods, such as general roughing, operate by deepening the cutting depth for as long as the tool is able to withstand it, giving a slower feed rate, less cutting depth, and faster feed. However, when the cutting depth is deep, there is a problem in that the stepped shape of the cutting area is increased (e.g., by the shaking of the tool or the chipping load). However, if the cutting is performed less, the cutting time becomes relatively long. To compensate for these drawbacks and extend the service life of the tool, economic efficiency needs to be secured.

• International Journal of Contents
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• 제15권2호
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• pp.38-43
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• 2019

Recently, bottom-up information systems (BUIS), developed according to the requirements of individual user departments, have become popular. However, effective management of BUIS projects is not enough, with many organizations having experienced integration challenges with such individual projects. BUIS projects are relatively small and limited in scope, as opposed to the large, complex systems developed through traditional top-down information system development projects. Due to these differences in characteristics, the control modes as well as the aspects to improve development performance in each type of project are also different. Therefore, it is difficult to apply the results of prior research on control in system development projects to improve BUIS project performance. The purpose of this study is to derive a new theory of control to improve BUIS project performance. The results contribute to the improvement of firm performance through effective control of BUIS projects in modern enterprises.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.676-681
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• 2001

In this paper, the spin-up from rest to a state of solid-body rotation in a circular container with a slender rectangular obstacle on the bottom wall is analysed experimentally. We use a PIV method for the evolution of the free-surface flow. Laboratory experiments have been carried out for a variety of the obstacle height h(0, 5, 10 [mm]) and the liquid depth H(25, 50, 75, 100 [mm]). It was found that the spin-up time is crucially dependent on the obstacle height T. In the case of T=10[mm] the spin-up time is considerably shorter then the other cases.

• 지적과 국토정보
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• 제47권2호
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• pp.185-199
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• 2017

본 연구는 예측하기 어려운 미래의 다양한 수요를 수용하기 위하여 재조합방법을 통한 공간정보제품 제작방법을 제안한다. 현재의 측량중심의 공간정보제품의 생산방안은 특정 지도제품 중심의 Top-down방식이므로 공간정보의 활용 확산 관점에서는 한계점을 가지고 있다. 이는 불특정 다수를 위한 공간정보의 활용성 관점보다는 모두를 위한 지도라는 관점에서 다양한 수요를 만족시키기에는 한계가 있다. 이런 한계점을 해결을 위해 사용자 맞춤형의 Bottom-up방식 공간정보 생산과 재조합을 통한 공간정보 제품 제작이 요구되고 있다. 이를 위해 본 논문은 기존의 Top-down 방식의 결과인 수치지도와 재조합을 통한 공간정보제품의 제작에 대한 이론적 고찰과 비교를 통해 보완 방안을 제안하였다. 이는 공간정보를 기초속성을 가지는 형태와 관계된 속성정보를 가지는 데이터로 재분류하고 각 데이터에 관계성 및 관리에 관한 속성을 부여하는 방안이다. 이 방법의 실효성 증명을 위해 기존 수요의 만족 가능성과 미래 수요의 대응 가능성을 중심으로 적용사례를 도출하였다, 그리고 기존의 국가기본도, 주제도, 향후 수요 예측 제품의 해당 대표제품을 제작하여 확인하였다.

• Fisheries and Aquatic Sciences
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• 제18권3호
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• pp.325-332
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• 2015

An active stimulating method for juvenile fishes to drive escaping from mesh of the codend was examined by shaking canvas in the bottom trawl followed by shrimp beam trawl. Field fishing trials by a bottom trawl were carried out between the Geomoondo and Jejudo in west of South sea, Korea by conver-net methods to examine the effect on the reduction of juvenile fish as a discard catch by generating a shaking movement of the codend using two pieces of asymmetrical semi-circular canvas. The mean period of the shaking motion with the round canvas was 10-15 s, and the range of amplitude as a vertical depth change was up to 0.4-0.6 m when towing speed 3.4-4.3 k't as estimated by peak event analysis. The escape rate of juvenile fish in conver-net by total juvenile bycatch (codend and cover-net) in 14 trials increased from 20% in a steady codend to 34% using a shaking codend in the bottom trawl, while the marketing catch or total bycatch was similar between steady and shaking cod ends. There was no difference in the body size of the fish and species composition between the steady and shaking cod ends. Above results demonstrate a new method for bycatch reduction actually up to 18% using an active stimulating device, although further experiments are needed to increase an effective shaking motion of the codend in amplitude and period for more bycatch reduction.

• 에너지공학
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• 제22권1호
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• pp.38-43
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• 2013

생활양식의 변화나 생활행위의 변화에 관련한 가정부문 에너지소비 패턴의 분석을 위해서 용도별 에너지소비자료 작성이 절실히 요청되어 왔다. 이에 따라, 생활행위의 분류에 의한 가정부문 용도별 에너지소비 분석모형을 개발하여 에너지소비 분석을 시도하였다. 본고에서는 부위(방)별 에너지 사용기기의 에너지 소비효율에 생활행위별 기기마다 가동시간을 곱해서 가구당 에너지소비량이 산출될 수 있도록 상향식의 가정 내 모형을 구축하였다. 생활행위 분류를 감안한 용도는 조명용, 난방용, 냉방용, 오락용, 정보용, 위생용, 취사용 등으로 구분하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.895-898
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• 1998

In this paper, we propose an efficient marker extraction algorithm for initial image segmentation in a bottom-up segmentation scheme. The proposed algorithm generates dense markers in visually complex areas and coarse markers in visually uniform areas. which conforms to the human perceptual system. Experimental results show that the proposed method achieves better subjective quality for fine initial image segmentation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.11-11
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• 2004

나노기술은 크게 2가지 접근방법을 가진다. 하나는 위에서 아래로(Top-Down)라는 관점으로 벌크물질로부터 이온빔 등을 이용해 이를 작게 잘라가는 방식이며, 다른 하나는 아래에서 위로(Bottom-Up) 방식으로 재질을 구성하는 분자를 재구성해 원하는 물성 및 특성을 가지도록 만드는 방법이다. 이 두 가지 접근 방법은 원하는 결과를 얻기 위해 상호 보완적으로 사용되기도 한다. Top-Down방식의 대표적인 기기로는 접속이온빔 장치(FIB, Focused Ion Beam)를 등 수 있으며, Bottom-Up방식의 대표적인 기기로는 SPM(Scanning Probe Microscope)을 들 수 있다.(중략)

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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• pp.404-411
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• 2002

The PSC 2-span-continuous-bridge by Up-Down Method on construction process is used for this research. It is measured the strain of lower-steel-plate at continuous section on the active range of negative moment at the stage of introducing compressive stress to bottom-plate and compared with results of structural analysis. On the basis of these results, it is confirmed the introduced compressive stress tか bottom-plate. The object of this research is presenting the degree of continuity at the stage of lifting up process.

• International Journal of Knowledge Content Development & Technology
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• 제4권1호
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• pp.39-51
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• 2014

The paper proposes that the Basic Concepts Classification (BCC) could serve as the controlled vocabulary for the Semantic Web. The BCC uses a synthetic approach among classes of things, relators, and properties. These are precisely the sort of concepts required by RDF triples. The BCC also addresses some of the syntactic needs of the Semantic Web. Others could be added to the BCC in a bottom-up process that carefully evaluates the costs, benefits, and best format for each rule considered.