• 제목/요약/키워드: Evaluation tool

검색결과 3,631건 처리시간 0.033초

공작기계 주축 시스템의 해석 자동화를 위한 툴 개발 (Development of a Tool for Automation of Analysis of a Spindle System of Machine Tools)

  • 최진우
    • 한국기계가공학회지
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    • 제14권2호
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    • pp.121-126
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    • 2015
  • In this research, a tool was developed for the rapid performance of three-dimensional finite element analysis (3D FEA) of a machine tool spindle system made of a shaft and bearings. It runs the FEA with data, such as the bearing stiffness and the coordinates of the points, to define the section of the shaft, bearing positions, and cutting point. developed for the spindle system and then implemented with the tool using an object-oriented programing technique that allows the use of the objects of the CAD system used in this research. Graphic user interfaces were designed for a user to interact with the tool. It provides rapid evaluation of the design of a spindle system, and therefore, it would be helpful to identify a near optimal design of a spindle system based on, say, static stiffness with design changes and, consequently, FEA.

외래간호사 역량 증진을 위한 간호역량 평가도구 개발 (Developing of a Tool for Ambulatory Care Nurse Competencies)

  • 민명진;유소영
    • 간호행정학회지
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    • 제23권1호
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    • pp.90-100
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    • 2017
  • Purpose: The purpose of this study was to develop a tool to evaluate the nursing competency of ambulatory nurses and to verify the reliability and validity of the developed tool for use in general hospitals. Methods: The evaluation tool for ambulatory nursing competency was developed through a literature review and tests for validity and reliability. Results: Subsequent to a review of the literature on nursing performance of ambulatory nurses, a 12 item questionnaire was developed. Through factor analysis, 12 items in a 2 factor solution were derived. Cronbach's ${\alpha}$ coefficient of the final instrument was .86. Conclusion: The assessment tool developed in this study allows for objective assessments of nursing competencies in relation to the competencies expected of ambulatory care nurses. It is hoped that the assessment tool can be used for empirical verification and to provide basic data for establishing the necessary policies to secure outstanding human resources.

엔드밀링 가공에서 절삭력 계수 데이터베이스 구현을 위한 일반화된 방법론 (Generalized Method for Constructing Cutting Force Coefficients Database in End-milling)

  • 안성호;고정훈;조동우
    • 한국정밀공학회지
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    • 제20권8호
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    • pp.39-46
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    • 2003
  • Productivity and machining performance can be improved by cutting analysis including cutting force prediction, surface error prediction and machining stability evaluation. In order to perform cutting analysis, cutting force coefficients database have to be constructed. Since cutting force coefficients are dependent on cutting condition in the existing research, a large number of calibration tests are needed to obtain cutting force coefficients, which makes it difficult to build the cutting force coefficients database. This paper proposes a generalized method for constructing the cutting force coefficients database us ins cutting-condition-independent coefficients. The tool geometry and workpiece material were considered as important components for database construction. Cutting force coefficients were calculated and analyzed for various helix and rake angles as well as for several workpiece. Furthermore, the variation of cutting force coefficients according to tool wear was analyzed. Tool wear was found to affect tool geometry, which results in the change of cutting force coefficients.

고속도로에서의 자율주행 알고리즘 개발 및 평가를 위한 다차량 시뮬레이션 환경 개발 (Multi-Vehicle Environment Simulation Tool to Develop and Evaluate Automated Driving Systems in Motorway)

  • 이호준;정용환;민경찬;이명수;신재곤;이경수
    • 자동차안전학회지
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    • 제8권4호
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    • pp.31-37
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    • 2016
  • Since real road experiments have many restrictions, a multi-vehicle traffic simulator can be an effective tool to develop and evaluate fully automated driving systems. This paper presents multi-vehicle environment simulation tool to develop and evaluate motorway automated driving systems. The proposed simulation tool consists of following two main parts: surrounding vehicle model and environment sensor model. The surrounding vehicle model is designed to quickly generate rational complex traffic situations of motorway. The environment sensor model depicts uncertainty of environment sensor. As a result, various traffic situations with uncertainty of environment sensor can be proposed by the multi-vehicle environment simulation tool. An application to automated driving system has been conducted. A lane changing algorithm is evaluated by performance indexes from the multi-vehicle environment simulation tool.

난삭성 재료의 가공환경변화에 따른 고속가공 특성 평가(압축공기냉각에 의한 공구수명 평가) (Evaluation of Machinability by Cutting Environments in High-Speed Machining of Difficult-to-cut Materials(Test for Tool Life Using Compressed Chilly Air Cooling))

  • 김석원;안철수;이득우
    • 한국생산제조학회지
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    • 제9권6호
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    • pp.158-163
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    • 2000
  • High speed machining of difficult-to-cut materials generates the concentrated thermal/frictional damage at the cutting edge of the tool and rapidly decreases the tool life. In this paper, the cutting environments, such as dry, fluid coolant, and compressed chilly air coolant, were investigated to improve the tool life. For this study, the compressed chilly air system was manufactured. The experiments were performed for various difficult-to-cut materials and various coated tools. The effectiveness of the developed methods on the basis of tool life was estimated. The results show that the cutting environment using compressed chilly air coolant provided better tool life than using the fluid coolant or using the dry.

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