• 제목/요약/키워드: in-process measurement

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Development of Computer Control Polishing System for Free Form Surface (자유곡면 연마를 위한 자동 연마 시스템 개발)

  • 전문식;오창진;이응석;김옥현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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    • pp.327-331
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    • 2001
  • In the process of optical parts machining, polishing has been applied. Traditional polishing process is suitable for spherical optical parts. But it is very difficult to apply traditional process for aspheric optical parts. Nowadays, as growing needs for aspherical optic parts, many researches have been conducted. In this study, we developed computer controlled polishing system which consists of three major parts of active pressure control for correcting polishing process, mechanical on-machine measurement for rough polishing, and optical on-machine measurement for finish polishing, respectively. In this paper, a systematic stretegy for correcting polishing process, pressure control scheme for polishing tool, and on-machine measurement methods for automated and precise polishing are suggested. The information about developed machine is also included.

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Measurement and Frequency Weighting Functions for Human Vibration

  • Kee, Dohyung;Park, Hee Sok
    • Journal of the Ergonomics Society of Korea
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    • 제32권4호
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    • pp.309-319
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    • 2013
  • Objective: The aim of this study is to review and summarize human vibration measurement process, and necessity and methods of frequency weightings for human vibration. Background: Prolonged human exposure to hand-arm vibration and whole-body vibration can result in a range of adverse conditions and the development of occupational diseases such as vibration white finger. For preventing these adverse effects, it is important to correctly apply human vibration measurement process. Method: This manuscript was based on the review and summary of mechanical and human vibration relevant texts, academic papers, materials obtained through web surfing. Results: This manuscript summarizes human vibration measurement process described in ISO standards and relevant texts. The sensitivity of the human body to mechanical vibration is known to be dependent on both the frequency and direction of vibration. To take this into account, varying frequency weighting functions have been developed, and RMS frequency-weighted accelerations are used as the most important quantity to evaluate the effects of vibration on health. ISO provided nine frequency weighting functions in the form of curves and tables. Researches on frequency weightings are focused on development and validation of new frequency weightings to truly reflect the relationship between vibration exposure and its adverse effects. Application: This would be useful information for systematically applying human vibration measurement and analysis process, and for selecting appropriate frequency weighting functions.

The Measurement Model for the Evaluation of Information Systems Service : The Case of Chinese SI Company (정보시스템 서비스 평가를 위한 측정모형의 개발 및 실증적 검증 : 중국 SI 기업 사례)

  • Lee, Sang-Jae;Lim, Gyoo-Gun
    • Journal of Information Technology Services
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    • 제10권2호
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    • pp.141-162
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    • 2011
  • The controls of Information Systems (IS) have been an more critical issue controls as the sophistication and integration of IS is more proceeded. ITGI (The Information Technology Governance Institute) of ISACA (Information Systems Audit and Control Association) has suggested COBIT (Control Objectives for Information and related Technology) and this has been widely recognized the evaluation model of IS controls. In COBIT, IS was evaluated in terms of process, information quality, and IT resources. This study used COBIT in order to suggest and empirically test an evaluation model of IS service. The data was collated from one major Chinese SI (Systems Integration) company in four domains of processes : planning and organization, acquisition and implementation, delivery and support, and monitoring. Seven factors are extracted using an exploratory factor analysis as follows : Overall IT planning process, technological assessment process in IT planning of IT, cost-benefit assessment process in IT planning, implementation process, support process, monitoring process, post-implementation evaluation process. The results of confirmatory analysis of three alternative measurement models indicated that the measurement model with one inherent or conceptual variable has greater model fitness than the other models. This study suggests the logical and general way to test and apply COBIT in evaluating IS services.

A Study for the Measurement System Assessment (측정시스템 평가에 관한 연구)

  • 백재욱
    • Journal of Korean Society for Quality Management
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    • 제26권4호
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    • pp.124-142
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    • 1998
  • It is essential to have a correct measurement system assessment to help improve process or quality. In this paper, we emphasize that a confidence interval a, pp.oach for the parameters of measurement error study and GR&R is crucial and a simple a, pp.oach for constructing them is presented. We also discuss on the issue of linearity of the gauge. Next, we try to reveal the relationship between measurement error and the process capability index. Finally some aspects of conducting the measuring experiment concerning the number of parts, number of measurements per part, and recommendations on how the experiment is to be performed will be considered.

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Process Design and Case Study for Efficient Function Point Measurement Based on Object Oriented (객체지향 기반 효율적인 기능점수 측정 프로세스 설계 및 사례연구)

  • Kim, Dong-Sun;Yoon, Hee-Byung
    • The KIPS Transactions:PartD
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    • 제15D권3호
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    • pp.375-386
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    • 2008
  • Recently, development paradigm of information system is turning into object oriented and component based, and this methodology is leading the software industry. To acclimatize aptly to this trend, users demand the assessment of software expenses to change with the appropriate model of computing costs of the environment, and some people are actually studying the concept of Object Oriented Function Point and UCP method. Especially, Object Oriented Function Point Measurement Process has good points in overcoming the bound of LOC and the existing the Function Point Measurement Process because Object Oriented Function Point Measurement Process is applicable to the early stage of development project mainly with the used cases, and valid to the life long period as the each stage of software products develops, and always understandable to communicate with users by the UML mark rules. Accordingly, this research is to measure Functional Point at ROFP and AOFP in accordance with the development project of information system by the national defense CBD methodology procedures and UML Interrelation Analysis that are recently and widely used in the developmental environment of object oriented information system. Furthermore, this study suggests the measurement method to obtain Functional Point, and identifies service function and object/class function in the correlation analysis of use case and class based on the products and UML modeling via traditional FPA model and object oriented FPA model. Above all, this study is to demonstrate the improvement of traditional Function Point Measurement Process, IFPUG-CPM and software cost basis, and reveal Function Point Measurement Process, which is appropriate to the development of object oriented information system, and suggest the evaluation results of the compatibility through case studies.

A case study on the application of process abnormal detection process using big data in smart factory (Smart Factory Big Data를 활용한 공정 이상 탐지 프로세스 적용 사례 연구)

  • Nam, Hyunwoo
    • The Korean Journal of Applied Statistics
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    • 제34권1호
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    • pp.99-114
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    • 2021
  • With the Fourth Industrial Revolution based on new technology, the semiconductor manufacturing industry researches various analysis methods such as detecting process abnormalities and predicting yield based on equipment sensor data generated in the manufacturing process. The semiconductor manufacturing process consists of hundreds of processes and thousands of measurement processes associated with them, each of which has properties that cannot be defined by chemical or physical equations. In the individual measurement process, the actual measurement ratio does not exceed 0.1% to 5% of the target product, and it cannot be kept constant for each measurement point. For this reason, efforts are being made to determine whether to manage by using equipment sensor data that can indirectly determine the normal state of each step of the process. In this study, the Functional Data Analysis (FDA) was proposed to define a process abnormality detection process based on equipment sensor data and compensate for the disadvantages of the currently applied statistics-based diagnosis method. Anomaly detection accuracy was compared using machine learning on actual field case data, and its effectiveness was verified.

A Study on the Efficiency Measurement Method for the Development Process of Online Content (온라인콘텐츠 개발프로세스의 효율성 측정방법 연구)

  • Yun, BongShik;Yoo, Sowol
    • Smart Media Journal
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    • 제11권1호
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    • pp.9-16
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    • 2022
  • With the development of online commercializing technology and the growth of online market, it has become extremely important for companies that aim to commercialize their products and services to control time and resources. Even when a single company has control over the entire process, it is necessary to maintain the efficiency among the process of development. In particular, when there is a lot of cooperation throughout the course of development, requiring many parties to communicate with each other, the issue of declining efficiency becomes much clearer. The timing of when to launch a product or service has become just as important as completing and testing them for companies. Companies have developed new tools to prevent situations that may lead to inefficiency in the development process, including an increase in the amount of resource used or issues with security maintenance. However, there is a lack of proper measurement tool that assesses what kind of additional benefits the entire process of the company is bringing, or whether or not the processes need to be improved in certain areas. Thus, this study aims to suggest a method to measure efficiency, to provide an empirical efficiency measurement method for the development process of online content.

Economic Evaluation of Measurement System by Principal Component Analysis (주성분 분석을 이용한 측정시스템의 경제적 평가)

  • Kang, Chung-Oh;Byun, Jai-Hyun
    • Journal of Korean Institute of Industrial Engineers
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    • 제24권2호
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    • pp.211-221
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    • 1998
  • It is very important to have a satisfactory measurement system, since it is useless to try to improve the manufacturing process without an adequate measurement system. Therefore, evaluation of the measurement system is the first step for the quality improvement of the manufacturing process. To estimate the measurement error we must conduct a controlled gage repeatability and reproducibility(gage R&R) study. Many manufacturers use a gage or instrument to measure multiple dimensions for the overall quality of the manufactured parts. In this case, it is necessary to estimate the gage R&R for multiple dimensions. When a gage measures a large number of dimensions of a part, it is very time-consuming and costly to measure all the dimensions. In this paper we propose the use of the principal component analysis method to identify a few principal components out of the original multivariate measurement capability to explain most of the measurement system variation pattern.

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A Study on Automated Outer Diameter Measurement System for Axisymmetric Automotive Part (자동차용 축대칭 형상 부품 외경 자동측정시스템에 관한 연구)

  • Ban, Kap-Soo;Bae, Jun-Young
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • 제12권3호
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    • pp.61-68
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    • 2013
  • Automatic measurement system is required since cycle time and cost of production are increased by various factors in manual systems. This paper presents a machine vision based prototype measurement system for the automotive axisymmetric shape parts which are generally measured by a manual system that is required the tolerance of the part is very small on each machined surface. This measurement system adopts a method in which optical lens is transferred along the profile of the part to minimize measurement cycle time. The main interest of this paper is a development of an optimum measurement algorithm to the outside diameter of the parts that can be applied to various combinations of hardware. The operating system used to implement the whole system is Window XP and corresponding environment.

A Study on the Development of the Learning Organization Measurement (학습조직화 측정도구 개발을 위한 연구)

  • Jeong, Seok-Hee;Lee, Kyung-Seon;Lee, Myung-Ha;Kim, In-Sook
    • Journal of Korean Academy of Nursing Administration
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    • 제9권1호
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    • pp.75-88
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    • 2003
  • Purpose : The Purposes of this study was to develop a learning organization measurement for nurses, and to test the validity and reliability of the measurement. Method : This study was conducted through 3 phases -theoretical framework choice, measurement items selection, and the testing of validity and reliability. In order to test reliability and validity of the measurement, data were collected from the 261 nurses, working in the 1 hospital with more 800 beds. The data obtained were analyzed by SPSS for Window program using percentages, Factor Analysis, Cronbach's alpha coefficients. Result : As a result of the study, 2 scales -Learning Organization Building Scale, and Knowledge Management Process Scale- were developed. Learning Organization Building Scale was consisted of 23 items, 5 factors. 5 factors explained 60.26% of the total variance, and the Cronbach's alpha of this scale was .8807. Knowledge Management Process Scale was consisted of 17 items, 4 factors. 4 factors explained 66.14% of the total variance, and the Cronbach's alpha of this scale was .9147. Conclusion : The Study supports the validity and reliability of the scales. Therefore, these scales can be effectively utilized for many researches about Learning organization of Nurse, and Nursing organization in the Hospital Setting.

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