• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.182-186
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• 2011

Early cost estimates are important to decision-making for a construction project. Moreover, the possibility of reducing the project cost is getting less as the project is progressed. Case-based reasoning (CBR), which can be viewed as an effective method for early cost estimating, is widely utilized recently. Early cost estimates using CBR have advantages over the traditional ones as they produce reasonable outputs and self-studying is possible by simply adding new cases. Case-based reasoning is composed of a cycle of retrieve, reuse, revise, and retain process. However, in the majority of research cases, they are focused on how to retrieve the similar cases, instead of revising the cases which is expected to increase accuracy results of cost estimation. This research suggests a method of revising retrieved similar cases in a GA-CBR cost model which is widely studied and utilized for early cost estimating recently. To validate the proposed method, case study is conducted based on Korean public apartment projects.

• Archives of Plastic Surgery
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• 제47권1호
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• pp.97-101
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• 2020

Although the success rate of deep inferior epigastric perforator (DIEP) flaps has increased, late flap failures still occur and have a low salvage rate. The present article describes a case of salvage of a case of late flap failure using the pedicle vein as a vein graft source. A 50-yearold woman underwent a bilateral DIEP free flap procedure. On postoperative day 6, she experienced flap compromise and underwent emergency flap revision. In the flap revision, flap venous drainage and the superficial inferior epigastric vein were completely obstructed. A Fogarty catheter was used to remove a thrombus from the completely obstructed pedicle vein, and this pedicle vein was used as a graft source and was ligated in retrograde fashion to the flap vein stump. After injection of urokinase into the arterial branch, venous flow to the flap was restored. At a 6-month follow-up visit in the outpatient clinic, only partial fat necrosis at the flap was noted. By dissecting various perforators in the initial operation, decisions regarding immediate revision can be made with more confidence. Additionally, the combined procedures performed in this case may be helpful even for practitioners treating cases of late flap compromise.

• 한국소음진동공학회논문집
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• 제11권9호
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• pp.414-421
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• 2001

If a machine has some faults, we can detect them using vibration or noise signals. However some maintenance engineers who don\`t have export knowledge, need the help of vibration experts for diagnosing the machine. In this paper a case based reasoning (CBR) system is developed which is able to manipulate the past experiences of vibration diagnosis experts. In the CBR system, the maintenance engineers can retrieve the information form previous cases which are most similar to new problem s that they can solve new problem using solutions form the previous cases. In this paper, a new case retrieval method of CBR system using Petri net is proposed and also applied to diagnosis for electric motors as a practical problem.

• 한국구조물진단유지관리공학회 논문집
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• 제4권4호
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• pp.171-180
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• 2000

This study aims to present a more reasonable control value than the exiting one by comparing and analyzing control values and field instrumentation values of the whole excavation depth of the four case sites using geometric averaging as a statistical method. The range of the study is confined to three things: (1) the axial force of the braced excavation walls among a variety of items prescribed in the control values by stress deformation of walls and adjacent structures; (2) by approximation of the allowable and design value; (3) and by safety factor. As a res it is desirable to revise "(Long term allowable stress + Short term allowable stress)/2 ~ Short term allowable stress," presented in the present control values by stress deformation of walls and adjacent structures, to "(Long term allowable stress + Short term allowable stress)/5 ~ (Short term allowable stress)/3." The result also shows that since there is a difference of about 3.5%, it is not necessary to revise 70, 90, and 100 percent of LEVEL I, II, and III, prescribed in the control values by the allowable and design value approximation. In addition, modifying the control value by the safety factor, now 1.07, is unnecessary, although it varies little difference from the present value.

• 한국조경학회지
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• 제41권1호
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• pp.60-70
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• 2013

본 연구는 조경공사 표준시방서 식재공사의 분류체계, 기술방식, 품질기준의 개정시기별 변화특성을 분석하고, 국외 사례와의 비교를 통하여 개선방향을 제시하고자 하였다. 이에 본 연구의 결과 및 제언은 다음과 같다. 1. 개정을 통해 다양한 세부공종이 신설 수정되었으나 상 하위분류가 맞지 않아 시방내용이 상충되고 있으므로 비슷한 공사끼리의 재분류가 필요하다. 2. 시방서 내용을 용이하게 전달하기 위한 기술방식으로 수정이 이루어졌다. 그러나 구체성이 떨어지는 애매모호한 표현과 용어로 유지되고 있는 굴취시 뿌리분의 깊이, 지주재 강도에 관한 내용은 수정이 필요하다. 또한 표토의 채취시기, 약제 살포시기 등은 계량화될 필요가 있으며, 시방규정의 공정성을 고려하여 감독자의 지시에 따르도록 작성된 기준은 수정되어야 한다. 3. 시대적 패러다임과 사용자의 요구를 반영한 품질기준이 제 개정되었으나 구체적이지 않아 수정이 필요하며, 관련 기준들의 국외 사례를 참고하여 수목재료의 품질수준, 식재적기, 굴취시 뿌리분의 크기, 성능기준 등을 개선해야 한다. 개정을 통해 식재공사의 세부공종별 재료 및 시공방법에 대한 내용은 갖춰졌다. 그러나 구체성이 떨어지고 명확하지 않은 기준들로 시방서의 현장 활용을 저해하고 있다. 이에 표준시방서의 분류체계, 기술방식, 품질기준의 문제점 도출과 개선방향의 제시가 필요하며, 이는 향후 표준시방서 개정시 참고자료가 될 수 있다.

• 한국IT서비스학회지
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• 제2권2호
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• pp.39-51
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• 2003

The Internet affects all economic activities. Physical world business must either adopt new digital strategies, launch new digital business to complement their physical world models, or be forced to completely revise their strategies. The purpose of this paper is to provide a framework that organizes the managerial decision-making process to assist managers in crafting and implementing e-business strategy. We applied the methodology to the case of KNK Educational Institute to explain the process. Core competence of KNK JUNIOR is researched according to our suggested methodology and activities and roles of KNK JUNIOR have been arranged.

• 대한전기학회논문지:전력기술부문A
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• 제52권1호
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• pp.50-57
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• 2003

In this paper, the protective relay setting rules of Korean electric power system are studied by analysis of errors to be considered. An accurate operation of protective relays with accurate settings are important in power system reliability. The setting rules are used from the first establishment in 1982 and revision in 1990 Therefore, it needs revise and analysis of the setting rules because of environmental changes such as voltage raise or applied new technology of power system. Two major setting rules are studied. One is the rule for Zones of distance relay for transmission lines. The other is the one of differential current in a differential relay for power transformers. The range of errors in the setting rules accepted in the field experience is studied in simulation of case study. Also some guide lines for the range of errors in the setting rules are presented from the case study using Matlab simulation.

• 농촌계획
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• 제15권3호
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• pp.81-87
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• 2009

It may be said that a farmer's crisis deepens from the number of farm households and a trend of the number of cultivated land of the farmer attracting attention for the most fundamental numerical value of the Census of Agriculture 2005. A rate of decline of number of farm households seems to have been stopped, but expansion lasts a number of farm households rate of decline. I can, so to speak, watch weakening of flatland area and luck of mountainous areas and a situation to say if I look in that according to classification agricultural area. I can nominate the effect of a direct payment system for farmers in hilly and mountainous areas enforced in 2000 for the background. It is located in case of the policy introduced preceding it while the rural community and the community including the urban area being paid attention as the last resort of a regional reproduction now. In particular, the character as the village activation subsidy has been strengthened in case of the 2nd stage institutional revise.

• 한국초등과학교육학회지:초등과학교육
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• 제30권3호
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• pp.353-366
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• 2011

An alternative vision for science inquiry that appears to be important and challenging is model-based inquiry in which students generate, evaluate and revise their explanatory model. Pre-service teachers should be given opportunities to develop and use their mechanistic explanatory models in order to participate in the practice of science and to have a sound understanding of science. With this view, this study described a case of pre-service elementary teachers' scientific modeling in magnetism. The aims of this study were to explore difficulties preservice elementary teachers encountered while they engaged in a model-based inquiry, and to examine how their understandings of the nature of scientific models changed after the model-based inquiry. The data analysis revealed that the pre-service teachers had difficulties in drawing and writing their own thinking because they had little experience of expressing their own science ideas. When asked to predict what would happen, they could not understand what it meant to make a prediction "based on their model". They did not know how to use or consider their model in making a prediction. At the end of the model-based inquiry they reached a final consensus of a best model. However, they were very anxious about whether the model was the "correct" answer. With respect to the nature of scientific models, almost all of the pre-service teachers initially viewed models only as a communication tool among scientists or students and teachers to help understand others' ideas. After the model-based inquiry, however, many of them understood that they could create, test, and revise their "own" models "by themselves". They also realized the key aspects of scientific models that a model can be changed as evidence is accumulated and a model is a knowledge production tool as well as a communication tool. The results indicated that pre-service elementary teachers' understandings of the nature of scientific models and their previous school science experiences could affect their performance on a model-based inquiry, and their experience of scientific modeling could help them enhance their understandings of the nature of scientific models.

• 지능정보연구
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• 제9권1호
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• pp.23-51
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• 2003

인터넷 쇼핑몰에서 사례기반추론기법을 통한 유사상품의 탐색과 사용자 요구에 적합한 상품추천을 위해서는 다양한 요구에 부응할 수 있는 사례베이스의 구축이 우선되어야 한다. 그리고 구축된 사례베이스로부터 유사한 사례를 검색하여 재 사용하거나 필요시 수정하고, 그 결과를 다시 저장하는 기능이 요구된다. 사례기반 상품추천시스템 개발에 있어 가장 중요한 요소는 사례의 표현문제이다. 본 연구에서는 인터넷 수산물 쇼핑몰의 상품추천시스템에서 번들상품 구성문제(집안 이벤트 시 필요한 수산물의 집합)를 표현하는데 적합한 사례표현기법을 개발하며, 유사사례를 추출하기 위한 유사도 척도의 개발에 연구의 첫 번째 주안점을 둔다. 본 논문에서는 번들상품추천을 위한 사례표현기법으로 객체모델링(OMT)기법을 사용하고 있다. 또한 다양한 사례 속성 유사도 측정방법을 적용하며, 유사도 측정에서 분류법(taxonomy)의 의미와 그 적용방법을 제시한다.