• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제11권4호
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• pp.157-162
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• 2022

오늘날 대부분의 데이터는 데이터베이스(database: DB)에 저장된다. 이러한 DB 환경에서 사용자는 자신이 원하는 데이터를 찾아줄 것을 DB에게 요청하게 된다. DB 질의 중 유사도 질의는 DB 사용자가 원하는 조건으로 유사도가 포함되어 있는 것을 말한다. 그러나 유사도 질의를 처리하기 위한 과정은 처리 레코드의 범위를 줄일 수 있는 색인을 이용하기 힘들어 테이블의 전체 레코드에 대해서 매번 유사도를 계산하는 비용이 높다. 본 논문은 이러한 문제점을 해결하기 위하여 경량 유사도 함수를 정의한다. 경량 유사도 함수는 유사도 함수에 비해 데이터를 여과하는 정확도는 떨어지지만 비용이 유사도 함수에 비하여 적게 소모되는 특징이 있다. 이러한 경량 유사도 함수의 특징을 이용하여 유사도 질의 처리 비용 감소 방법을 제시한다. 그리고 유클리드 거리 함수에 경량 유사도 함수로 체비쇼프 거리를 제시하고 기존의 유사도 함수를 이용하는 질의와 경량 유사도 함수를 이용하는 질의의 처리 비용을 비교한다. 그리고 실험을 통하여 유클리드 유사도에 대한 경량 유사도 함수로 체비쇼프 거리를 적용하였을 때 유사도 질의 처리 비용이 감소하는 것을 확인한다.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.597-598
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• 2015

In order to improve the reliability of cost estimation results using CBR, there has been a continuous issue on similarity measurement to accurately compute the distance among attributes and cases to retrieve the most similar singular or plural cases. However, these existing similarity measures have limitations in taking the covariance among attributes into consideration and reflecting the effects of covariance in computation of distances among attributes. To deal with this challenging issue, this research examines the weighted Mahalanobis distance based similarity measure applied to CBR cost estimation and carries out the comparative study on the existing distance measurement methods of CBR. To validate the suggest CBR cost model, leave-one-out cross validation (LOOCV) using two different sets of simulation data are carried out. Consequently, this research is expected to provide an analysis of covariance effects in similarity measurement and a basis for further research on the fundamentals of case retrieval.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.883-889
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• 2009

The importance of cost estimate in early stage such has been increasing due to market change and severe competition in construction industry. Because the adjustable budget is only 20% after design stage, most of the crucial decisions to influence cost is made in the early stage. However, in the early stage, the project scope is not defined completely so that estimator has inaccurate information to make critical decision. Therefore, this research suggests the cost estimate method using case-based reasoning. Case-based reasoning is appropriate for the early cost estimating, as it has the strength of rapidity and convenience in cost estimation. This research analyzes 84 actual data of public apartment on the scale of 11~15 stories. In order to extract the most similar case, at the first step this research identifies influence factors and calculates attribute similarity. In case-based reasoning, the most challenging task is determining attribute weight. At the third step, this research calculates case similarity which is aggregated attribute similarity multipled by attribute weight. Finally, extracts the most similar case which has the highest score of case similarity.

• 한국콘텐츠학회논문지
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• 제16권7호
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• pp.667-680
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• 2016

하둡 맵리듀스와 같은 분산 컴퓨팅 플랫폼이 개발됨에 따라, 기존 단일 컴퓨터 상에서 수행되는 질의 처리 기법을 분산 컴퓨팅 환경에서 효율적으로 수행하는 것이 필요하다. 특히, 주어진 두 데이터 집합에서 유사도가 높은 모든 데이터 쌍을 탐색하는 유사 조인 질의를 분산 컴퓨팅 환경에서 수행하려는 연구가 있어 왔다. 그러나 분산 병렬 환경에서의 기존 유사 조인 질의처리 기법은 데이터 전송 비용만을 고려하기 때문에 클러스터 간에 비균등 연산 부하 분산의 문제점이 존재한다. 본 논문에서는 분산 컴퓨팅 환경에서 효율적인 유사 조인 처리를 위한 행렬 기반 부하 분산 알고리즘을 제안한다. 제안하는 알고리즘은 클러스터의 균등 부하 분산을 위해 행렬을 이용하여 예상되는 연산 부하를 측정하고 이에 따라 파티션을 생성한다. 아울러, 클러스터에서 질의 처리에 사용되지 않는 데이터를 필터링함으로서 연산 부하를 감소시킨다. 마지막으로 성능 평가를 통해 제안하는 알고리즘이 기존 기법에 비해 질의 처리 성능 측면에서 우수함을 보인다.

• 한국음향학회지
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• 제38권3호
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• pp.314-319
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• 2019

음악 커버곡 검색 시스템 구현에 있어서 크로마그램 간 유사도 계산은 필수적인 구성 요소이다. 본 논문은 크로마그램 비교에 소요되는 저장공간 및 계산량을 줄이기 위한 크로마그램 코딩 방법을 제안한다. 음악별로 코드북을 학습하여 크로마그램 수열을 코드 수열로 변환하여 저장 공간을 줄이게 된다. 얻어진 코드 간 거리를 룩업 테이블에 저장하여 크로마그램 비교의 속도를 개선하였다. 두 가지 커버곡 실험 데이터셋에서 성능 비교를 수행하여, 제안된 코드 기반 방법과 기존 방법 간의 커버곡 검색 정확도, 저장 공간, 계산량을 비교하였다.

• 한국정밀공학회지
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• 제19권12호
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• pp.142-149
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• 2002

In this paper, the metal forming process is caused of rise of the unit cost of production in increase of the lead-time and cost because of manufacturing final product through a few the number of processes. Flow control complex forming is proposed to put into formulation in order to apply cold forging from conventional approximate similarity theory, and the forming loads of the real material(AISI 1008) can be calculated by put at the new similarity formula the load by plasticine model material experiment through hub clutch. In order to reduce lead-time and cost the technology is used to manufacture with lower die of this product. By the application synthetic resin as the raw material, it is have the merit such short lead-time, low cost, good surface finish etc., as compared with the machine work.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.162-163
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• 2014

Operation and maintenance stage consists the largest portion of project life cycle cost. Appropriate management and analysis of such stages have massive effect on the total project cost. The effective prediction of optimized repair period is one of main factors in ㅌ management. However, it has been analyzed that the prediction of appropriate repair period revealed limitations in reliability. Therefore, this study suggests a methodology of repair period prediction by dividing finished projects into similar groups with same properties to be compared with the target project using quantitative variables.

• 대한산업공학회지
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• 제41권2호
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• pp.150-161
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• 2015

This paper proposes a new approach to technology valuation, the market-replacement cost approach which integrates the cost-based approach and market-based approach. The proposed approach estimates the market-replacement cost of a target technology using R&D costs of similar R&D projects previously conducted. Similar R&D projects are extracted from project database based on document similarity between project proposals and technology description of the target technology. R&D costs of similar R&D projects are adjusted by mirroring the rate of technological obsolescence and inflation. Market-replacement cost of the technology is then derived by calculating the weighted average of adjusted costs and similarity values of similar R&D projects. A case of "Prevention method and system for the diffusion of mobile malicious code" is presented to illustrate the proposed approach.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.143-147
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• 2010

Due to the diversification and complication of construction projects, controlling risks from the early design-planning phase gives huge impact on success of the construction project. As a part of managing uncertainties it is also important to estimate the project cost several times. Especially, estimating project cost in the early stage gives effects on making a budget for projects. This study estimated the apartment project cost using case-based reasoning(CBR), which is the process of solving new problems based on the past problems. For this, we deduced the apartment cost influence factors which can be gathered in the early stage of project. Based on the factors we established the database for apartment project and calculated the attribute value, attribute similarity and case similarity. Although we retrieve the most similar case from the database, it is very hard to utilize it directly due to the uniqueness of each project. So, Genetic Algorithm(GA) was applied in revising the cost of the retrieved-case. Therefore, the accuracy of the prediction was improved by GA optimization.

• 패션비즈니스
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• 제26권1호
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• pp.53-67
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• 2022

The purpose of this study was to compare the appearance similarity between a 3D virtual wedding dress, and a model wearing real dress, and production efficiency, and the possibility of achieving similar results with 3D digital technology. Five wedding dresses for small weddings under the theme of 'Dream Series', were designed and produced in virtual and real dresses to quantitatively compare and analyze the appearance similarity and production efficiency. Experts compared the appearance similarity on the silhouettes, colors, materials, and details, and production efficiency was compared with time and cost. Based on our results, 3D virtual images of four out of the five dresses were similar to the real images. Our efficiency evaluation results showed that the manufacturing time was 45.4% shorter, and the manufacturing cost was 46.1% less than the existing method. This indicated that the wedding dress manufacturing process using 3D virtual software was time and cost saving competitive. Our results also confirmed that 3D virtual software technology has the potential to increase the efficiency of designing and production, and therefore an increase in competitiveness and sales of wedding dresses. Furthermore, 3D technology allows consumers to select and order wedding dresses online through 3D virtual software. This is a great advantage, and it highlights the significance of this research study.