• 제목/요약/키워드: Selection Tools

검색결과 448건 처리시간 0.022초

Tool selection problem in flexible manufacturing systems

  • Kato, Kiyoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.1553-1556
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    • 1991
  • This paper deals with a problem on the selection of alternative tools in a flexible manufacturing system (FMS) where a lot of tools are required to produce a large variety of product items. An approach using branch and bound method is proposed to minimize a total number of tools required through the optimal use of the alternative tools. In this approach, tools are initially divided into tool subgroups based on graph theory for the purpose of the effective search of the optimal solution. A small example is also presented to highlight the effectiveness of the proposed approach.

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자동공정설계(自動工程設計)에서 가공작업(加工作業)의 선정(選定) 및 순서결정(順序決定) 기법(技法)의 개발(開發) (An Automated Process Selection and Sequencing Method in Computer-Aided Process Planning)

  • 조규갑;김인호;노형민
    • 대한산업공학회지
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    • 제15권2호
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    • pp.45-55
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    • 1989
  • This paper deals with development of a computer-aided process selection and sequencing technique and its software for metal cutting processes of rotational parts. The process selection procedure consists of selection for proper machining operations and machine tools suitable for the selected operations. Machining operations are selected based on machining surface features and machine tools are selected by employing a conversion table which converts machining operations into machine tools. The process sequence is determined by the proper manipulation of the precedence relation matrix. A computer program for the proposed technique is developed by using Turbo-Pascal on IBM PC/AT compatible system. The proposed technique works well to real problems.

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어린이 도서 서평 매체에 관한 연구 (An Analytic81 Study of Children's Book Review Media)

  • 장지숙
    • 한국문헌정보학회지
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    • 제38권2호
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    • pp.213-238
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    • 2004
  • 본 연구는 어린이 도서에 대한 서평을 제공하는 각종 매체의 존재를 확인하고, 그러한 매체에 수록된 서평이 선정 도구로 적합한지를 평가하였으며, 이러한 과정을 통하여 보다 적절한 서평 매체로서의 역할을 증진하기 위해서 기존의 어린이 도서 서평 매체의 문제점을 분석하고 발전 방안을 제시하였다. 우리나라에서 활용할 수 있는 어린이 도서 서평 매체중 추천한 매체만을 대상으로 한 서평 분석 결과에 의하면 선정 도구로 활용할 수 있을 정도의 정보를 모두 제공하는 서평 매체는 없다고 할 수 있다. 따라서 도서관과 사서의 관점에서 어린이 도서를 평가한 서평 매체의 발행이 요구된다.

Simple Statistical Tools to Detect Signals of Recent Polygenic Selection

  • Piffer, Davide
    • Interdisciplinary Bio Central
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    • 제6권1호
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    • pp.1.1-1.6
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    • 2014
  • A growing body of evidence shows that most psychological traits are polygenic, that is they involve the action of many genes with small effects. However, the study of selection has disproportionately been on one or a few genes and their associated sweep signals (rapid and large changes in frequency). If our goal is to study the evolution of psychological variables, such as intelligence, we need a model that explains the evolution of phenotypes governed by many common genetic variants. This study illustrates simple statistical tools to detect signals of recent polygenic selection: a) ANOVA can be used to reveal significant deviation from random distribution of allele frequencies across racial groups. b) Principal component analysis can be used as a tool for finding a factor that represents the strength of recent selection on a phenotype and the underlying genetic variation. c) Method of correlated vectors: the correlation between genetic frequencies and the average phenotypes of different populations is computed; then, the resulting correlation coefficients are correlated with the corresponding alleles' genome-wide significance. This provides a measure of how selection acted on genes with higher signal to noise ratio. Another related test is that alleles with large frequency differences between populations should have a higher genome-wide significance value than alleles with small frequency differences. This paper fruitfully employs these tools and shows that common genetic variants exhibit subtle frequency shifts and that these shifts predict phenotypic differences across populations.

절삭 공구 자동 선정 프로그램 개발 (Development of Automatic Cutting Tool Selection Program)

  • 김영진
    • 한국CDE학회논문집
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    • 제3권3호
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    • pp.177-182
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    • 1998
  • The computer related techniques have been developed rapidly in the field of metal removal industry. The electronic catalog for mechanical elements is one of such developments realized in recent years. As the emergence of the electronic catalogs in the 90s, it breaks the restriction of the traditional catalog and becomes a helpful and efficient tool in the field. In this paper, we develop an electronic catalog for the cutting tools of the Korea Tungsten Co. Ltd. The catalog consists of three parts: a preprocessor for tool selection, a database for tool, and a postprocessor for search result. A preprocessor for tool selection is developed under a user-friendly consideration. A database for tool consists of milling, drilling, and reaming tools with a list of cutters, inserts, and components. A postprocessor for search result consists of weight, dimension. drawing, product order number etc. of the tools. It also suggests the optimized cutting condition of the selected tool using a neural network technique which is done by an independent research group.

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모델 기반 선택 기준을 이용한 소프트웨어 메트릭 및 도구 선택 방법 (Selection Method of Software Metrics and Metric Tools using Model-Based Selection Criteria)

  • 송동훈;서용진;김현수
    • 정보과학회 컴퓨팅의 실제 논문지
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    • 제24권1호
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    • pp.46-52
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    • 2018
  • 소프트웨어 메트릭은 소프트웨어를 평가하기 위한 방법으로, 소프트웨어의 개발 비용을 줄이고 품질을 향상시키는데 큰 역할을 하고 있다. 하지만 다양한 소프트웨어 메트릭이 등장하면서 적재적소에 사용하기 위한 메트릭 선택 문제가 발생했고, 이를 해결하고자 다양한 방법들이 연구되었다. 하지만 기존 연구들은 사용자의 높은 개입을 요구함으로써 여전히 메트릭 선택의 어려움을 가지고 있다. 따라서 본 논문에서는 사용자의 개입을 최소화하기 위해 가중치 표현을 지양하고 메트릭 및 메트릭 도구에 대한 다양한 특성을 선택 기준으로 사용하여, 메트릭 및 메트릭 도구 선택에 도움을 주는 방법을 제안한다.

공작기계 열오차 모델의 최적 센서위치 선정 (Selection of Optimal Sensor Locations for Thermal Error Model of Machine tools)

  • 안중용
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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    • pp.345-350
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    • 1999
  • The effectiveness of software error compensation for thermally induced machine tool errors relies on the prediction accuracy of the pre-established thermal error models. The selection of optimal sensor locations is the most important in establishing these empirical models. In this paper, a methodology for the selection of optimal sensor locations is proposed to establish a robust linear model which is not subjected to collinearity. Correlation coefficient and time delay are used as thermal parameters for optimal sensor location. Firstly, thermal deformation and temperatures are measured with machine tools being excited by sinusoidal heat input. And then, after correlation coefficient and time delays are calculated from the measured data, the optimal sensor location is selected through hard c-means clustering and sequential selection method. The validity of the proposed methodology is verified through the estimation of thermal expansion along Z-axis by spindle rotation.

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3차원 포켓가공을 위한 절삭층 형성 및 공구선정 (Generation of Cutting Layers and Tool Selection for 3D Pocket Machining)

  • 경영민;조규갑
    • 한국정밀공학회지
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    • 제15권9호
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    • pp.101-110
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    • 1998
  • In process planning for 3D pocket machining, the critical issues for the optimal process planning are the generation of cutting layers and the tool selection for each cutting layers as well as the other factors such as the determination of machining types, tool path, etc. This paper describes the optimal tool selection on a single cutting layer for 2D pocket machining, the generation of cutting layers for 3D pocket machining, the determination of the thickness of each cutting layers, the determination of the tool combinations for each cutting layers and also the development of an algorithm for determining the machining sequence which reduces the number of tool exchanges, which are based on the backward approach. The branch and bound method is applied to select the optimal tools for each cutting layer, and an algorithmic procedure is developed to determine the machining sequence consisting of the pairs of the cutting layers and cutting tools to be used in the same operation.

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포켓형상가공을 위한 최적공구 선정방법 (An Optimal Tool Selection Method for Pocket Machining)

  • 경영민;조규갑;전차수
    • 한국정밀공학회지
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    • 제14권7호
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    • pp.49-58
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    • 1997
  • In process planning for pocket machining, the selection of tool size, tool path, overlap distance, and the calculation of machining time are very important factors to obtain the optimal process planning result. Among those factors, the tool size is the most important one because the others depend on tool size. And also, it is not easy to determine the optimal tool size even though the shape of pocket is simple. Therefore, the optimal selection of tool size is the most essential task in process planning for machining a pocket. This paper presents a method for selecting optimal toos in pocket machining. The branch and bound method is applied to select the optimal tools which minimize the machining time by using the range of feasible tools and the breadth-first search.

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채용 전형에서 인공지능 기술 도입이 입사 지원의도에 미치는 영향 (The Impact of Artificial Intelligence Adoption in Candidates Screening and Job Interview on Intentions to Apply)

  • 이환우;이새롬;정경철
    • 한국정보시스템학회지:정보시스템연구
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    • 제28권2호
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    • pp.25-52
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    • 2019
  • Purpose Despite the recent increase in the use of selection tools using artificial intelligence (AI), far less is known about the effectiveness of them in recruitment and selection research. Design/methodology/approach This paper tests the impact of AI-based initial screening and interview on intentions to apply. We also examine the moderating role of individual difference (i.e., reliability on technology) in the relationship. Findings Using policy-capturing with undergraduate students at a large university in South Korea, this study showed that AI-based interview has a negative effect on intentions to apply, where AI-based initial screening has no effect. These results suggest that applicants may have a negative feeling of AI-based interview, but they may not AI-based initial screening. In other words, AI-based interview can reduce application rates, but AI-based screening not. Results also indicated that the relationship between AI-based initial screening and intentions to apply is moderated by the level of applicant's reliability on technology. Specifically, respondents with high levels of reliability are more likely than those with low levels of reliability to apply for firms using AI-based initial screening. However, the moderating role of reliability was not significant in the relationship between the AI interview and the applying intention. Employing uncertainty reduction theory, this study indicated that the relationship between AI-based selection tools and intentions to apply is dynamic, suggesting that organizations should carefully manage their AI-based selection techniques throughout the recruitment and selection process.