• Journal of the Korean Society for Precision Engineering
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• v.17 no.1
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• pp.120-128
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• 2000

One of the major limitations of productivity and quality in metal cutting is the machining accuracy of machine tools. The machining accuracy is affected by geometric errors, thermally-induced errors, and the deterioration of the machine tools. Geometric and thermal errors of machine tools should be measured and compensated to manufacture high quality products. In metal cutting, the machining accuracy is more affected by thermal errors than by geometric errors. This paper models of the thermal errors for error analysis and develops on-the-machine measurement system by which the volumetric error are measured and compensated. The thermal error is modeled by means of angularity errors of a column and thermal drift error of the spindle unit which are measured by the touch probe unit with a star type styluses and a designed spherical ball artifact (SBA). Experiments, performed with the developed measurement system, show that the system provides a high measuring accuracy, with repeatability of $\pm$2${\mu}{\textrm}{m}$ in X, Y and Z directions. It is believed that the developed measurement system can be also applied to the machine tools with CNC controller. In addition, machining accuracy and product quality can be improved by using the developed measurement system when the spherical ball artifact is mounted on the modular fixture.

• Journal of the Korean Society of Safety
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• v.37 no.3
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• pp.60-70
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• 2022

The use rate of sports facilities in Korea is increasing every year, which means that accidents are also increasing. However, it is difficult to determine the level of safety management necessary to prevent accidents because there are no measurement tools to evaluate such management of sports facilities. Accordingly, in this study, tools and models to evaluate the safety management level of public sports facilities were developed based on public company management evaluation guidelines and the EFQM Excellence Model. A comparative analysis of the proposed tools and models between local governments showed no difference in awareness of safety management by group. This means that active safety management activities are needed to improve the low level of interest in safety of public sports facilities. We hope that this model will be widely used for the safety management of public sports facilities and to identify improvements and priorities in safety management.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.1
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• pp.82-88
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• 1998

It is very important to test linear cycle positioning accuracy of NC lathes as it affect all other machines machined by them in industries. For example, if the linear positioning accuracy of x or z-axis directions is bad, the size of works will be wrong and the change-ability will be bad in the assembly of machine parts. In this paper , measuring systems are organized to measure linear displacement of ATC(Automatic tool changer) of NC lathe using laser interferometer, magnescale and tick pulses coming out from computer in order to get data at constant time intervals from the sensors, And each set of data gotten from test is expressed to a plots by computer treatment and the results of linear positioning error motion is estimated to numerics by statistical treatments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.527-532
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• 1993

MascMC system is one of the MMC system module which performs measuring and checking of machined workpieces on the machine tools. Accuracy of the MascMC was compensated for developing a reliable measuring system by measurement error calibration. Reference gauges, ring gauges, block gauges,squares, spheres and cylindrical squares, were used for error identification and compensation. .+-. 10 .mu. m accuracy with 95% confidence interval was confirmed on the vertical and the horizontal machining center through the large number of experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.116-120
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• 1991

Technique of length measurement error is widely used in the accuracy assessment of CMMS(Coordinate measuring machines) and machine tools, as it is simple and direct measurement within the working volume of a machine. In this paper, a new method is proposed for the evaluation of the length measurement error in relation to the volumetric accuracy. lD, 2D, and 3D measuring lines are considered for recpective length measurement error: 1D, 2D, and 3D length measurement uncertainties are evaluated from volumetric accuracy. The relationship between the volumetric accuracy md length measurement error to is discussed. PC based system for length measurement error evaluation and simulation is developed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.3
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• pp.51-51
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• 1998

It is very important to test linear cycle positioning accuracy of Machining centers as it affect all other machines machined by them in industries. For example, if the linear positioning accuracy of each axes directions is bad, the size of works will be wrong and the change-ability will be bad in the assembly of machine parts. In this paper, measuring systems are organized to measure linear displacements of table or spindle of machine center using laser interferometer, magnescale and tick pulses comming out from computer in order to get data at constant time intervals from the sensors. And each set of data gotten from test is expressed to a plots by computer treatment and the results of linear positioning error motion is estimated to numerics by statistical treatments.

• KIEAE Journal
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• v.4 no.4
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• pp.45-52
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• 2004

Simulation of daylighting by computer program is a method to avoid unnecessary efforts in manufacture of its testing models, to reduce its measuring tolerances and be able to provide variations of various weather conditions as well. Many simulation programs on daylighting have been released freely or commercialized for selling, however, a demonstration of their availability and validity as a tool for evaluating daylighting performance is required since each one has its own characteristics. The objectives of this study lie in suggesting an application method of evaluation tools and demonstration of limits and characteristics so as to more easily determine the daylightingperformance in the very initial stages of planning for an arbitrary office space in which windows with daylight access are built. We produced scale model of the general light inducing type side lighting with lightshelfand ceiling, and the luminance (at 78 measuring points) and illuminance (at 84 measuring points) were measured in a clear sky. And a comparison of the measured values and the calculated values from a computer simulation using the Lightscape program was performed.

• Journal of Distribution Science
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• v.14 no.1
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• pp.85-91
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• 2016

Purpose - Recently, the importance of rapid change in business models is more and more increasing as the change of information technology environment. Therefore, a variety of business models have emerged. On the other hand, there is no company that can generate revenue. Many enterprises are still maintained while they are changing only their appearance of the business model. Business model is important in e-commerce. However, a lot of researches are targeted only in Web sites. Thus, e-commerce companies do not have the infrastructure for measuring and business models. The purpose of paper is to evaluate factors which are related with the structuring of the e-commerce success. And it proposed a financial items and non-financial items. From the perspectives of administrators and managers, the paper researches the possibility for E-Commerce Evaluation Model as a valuable criteria in measuring business model. Research design, data and methodology - The methods are taken by the classification for the type of business-to-business transactions, transactions subject, and the degree of integration and innovation capabilities. Financial and Non-financial value is used to build E-Commerce Evaluation Model. Evaluation items in Administration's perspective are composed with enhance the effectiveness of the mission, improving efficiency of the administration, and control of costs. Evaluation items in the customer's perspective were measured by customer participation and cooperation with customer Satisfaction. In the case of researching the information system's perspective, three criteria are used such as adequacy of the development process, improvement of the quality of service, and maintenance of standardized information technology. In researching for the ICT competence's perspective, evaluation items were composed of enhanced user capabilities, utilizing new technologies, and empowerment of information workers. Results - In this paper, E-Commerce Evaluation Model with financial and non-financial perspectives shows the possibility to be criteria in the case of measuring business model. Moreover, it gives the positive expectation to be successful criteria. But the research may have ambiguity in its essential concept because it cannot avoid the limitation in selecting evaluation tools from merely the model. It is impossible to exclude the possibility in omitting specific properties which may take place in actual case study. Therefore, In hereafter research, it is necessary to include actual case study research in selecting evaluation tools in order to improve the limit point. Actual measurement items which are derived from actual case study should be subdivided, and it would be more effective to complete the research. Conclusions - In rapid change in business models, there are various kinds of business models. But it is general situation that companies which adopted business models have not brought in revenue. For this reason, E-Commerce Evaluation Model is needed as an important factor for the structuring of the e-commerce success. Although it has the limitation in selecting evaluation tools from model, E-Commerce Evaluation Model proposes the implication for measuring business models as a valuable criteria.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.3
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• pp.129-141
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• 2013

Objectives : Anorexia is the primary symptom impinging cancer patients' Quality of Life. It is usually accompanied by gastrointestinal symptoms(GI symptoms). Thus, to measure anorexia symptom precisely, assessing anorexia and GI symptoms together is recommended. This study was designed to analyze cancer-related anorexia assessment tools, extract GI symptoms included in these tools and investigate usefulness of instruments in clinical trials. Methods : Instruments were selected by searching PubMed, PROQOLID database. We analyzed instruments by number of items, assessment method, type of question, GI symptoms. Results : 9 instruments were selected to assess cancer-related anorexia symptom. Most tools adopt Likert scale as response scale and 'during past week' as recall period. Assessment method of all 9 instruments is the self-administration. Questions measuring anorexia are able to be sorted into 3 forms (frequency, severeness, distress of anorexia symptom). Among the GI symptoms, nausea is included in all 9 instruments. In clinical trials of cancer-related anorexia, Edmonton Symptom Assessment Scale(ESAS) and Functional Assessment of Anorexia/Cachexia Therapy Questionnaire(FAACT) were selected as endpoint measure. Conclusions : The result showed that FAACT is the only specialized tool to assess cancer-related anorexia. To measure cancer-related anorexia precisely, the need to develop new instrument exists.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.6
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• pp.68-73
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• 2009

One of the traditional optical methods to monitor a tool is a CCD sensor-based vision system which captures an aspect of the tool in real time. In the case using the CCD sensor, specific lens-modules are necessary to monitor the tool with higher resolution than its pixel size, and a microprocessor is required to attain desired data from captured images. Thus theses additional devices make the entire measurement system complex. Another method is to use a pair of an optical source and a detector per measuring axis. Since the method is based on the intensity modulation, the structure of the measurement system is simper than the CCD sensor-based vision system. However, in the case measuring the three dimensional position of the tool, it is difficult to apply to micro machine-tools because there may not be space to integrate three pairs of an optical source and a detector. In this paper, in order to develop a tool-origin measurement system which is employed in micro machine-tools, the improved method to measure a tool origin in x, y and z axes is introduced. The method is based on the intensity modulation and employs one pair of an optical source radiating divergent beams and a quadrant photodiode to detect a three dimensional position of the tool. This paper presents the measurement models of the proposed tool-origin sensor. The models were verified experimentally The verification results show that the proposed method is possible and the induced models are available for design.