• Journal of the Korean Society for Precision Engineering
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• v.20 no.12
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• pp.34-41
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• 2003

This paper suggests a methodology fur improving the machining accuracy by compensating for the machining errors based on on-machine measurement process. Probing errors and machine tool errors included in the measurement data were calibrated or compensated to obtain the actual machining errors. Machine tool errors were modeled in forward and backward directions according to the axis movement direction to consider the effects of backlash errors on the measurement data, and model parameters were determined by measuring a cube array artifact. A rectangular workpiece was machined and then measured with a touch probe as a verification experiment. Machining experiments showed that the machining errors were reduced to within the designated tolerance after compensating for the actual machining errors by modifying the original footpath for the next-step machining.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.197-209
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• 2018

Recently, many start-up failures occur as the number of attempts to start a business increases in a social atmosphere that encourages start-up. In particular, young entrepreneurs have a lower survival rate than general entrepreneurs because young entrepreneurs are challenging just with a simple idea to overcome the difficulties of employment while lacking prior knowledge and experience of business. Therefore, the reason for the failure of start-up is lack of preparation for start-up and lack of entrepreneurship. The purpose of this study is to develop a measurement tool to build a basic framework for entrepreneurship development and start - up preparation activities for young people. To develop an entrepreneurship measurement tool, researchers developed a preliminary question through qualitative research methods such as literature research, focus group interview, and expert verification. After that, researchers surveyed 102 entrepreneurs using quantitative research method and to verify the construct validity of the measurement tool, the final entrepreneurship measurement tool was completed through exploratory factor analysis and confirmatory factor analysis. The entrepreneurship measurement tool developed through this research process consists of 7 components and 15 measurement items. First, in the step of 'confirming entrepreneurial intention', two items of 'self-analytic competence', three items of 'ability of establishing start-up philosophy'are contained. Second, in the step of 'drawing up a start-up model', two items are contained in each category such as, 'ability of eliciting entrepreneurial idea,' 'ability of analyzing idea validity,' 'competence of planning a venture start-up model'. Third, in the step of 'planning the venture start-up,' two items are contained in each category such as, 'business-plan presentation competency,' 'ability of implementing organizational system.'. The measurement tool of entrepreneurship is meaningful as it could help young entrepreneur find out their lacking competence in preparing their start-ups and strengthen necessary competences by measuring their own entrepreneurship. Rather in the entrepreneurship education, basic data that can diagnose the entrepreneurship of young entrepreneurs is provided.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.8
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• pp.863-872
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• 2012

The squareness measurement of driving axes of a machine tool is very important to evaluate the performance of the machine. Laser interferometer measurement system is one of the most reliable equipment to measure the squareness. However, squareness measurement using laser system with an optical square result in restriction of straightness optics setup and Abbe's offset. This offset combines with angular errors during the motion of an axis to cause Abbe's error. In addition, the difficulty in optical square setup causes restriction of other optics and limitation of measurable range. In this paper, mathematical approaches are presented to eliminate the Abbe's error and to estimate squareness for full range by using the best fit of straightness data measured without an optical square. Experiments for squareness measurement of 3 axis machine tool were conducted and the proposed techniques were used for squareness evaluation with elimination of Abbe's error and squareness estimation for the full travel range.

• International Journal of Quality Innovation
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• v.9 no.2
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• pp.11-30
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• 2008

The purpose of this study is to develop BSC model of social enterprise. Performance analysis tool of BSC have been brought over from the business world, designed and created from the perspectives of profit-based businesses. The BSC is a strategic performance measurement and management tool designed for the private sector acting as a communication/information and learning system, to measure 'where we are now' and 'where to aim for next'. It prescribes a plan for translating 'vision' and 'strategy' into concrete action across four perspectives at different stages, depending on the business. These perspectives are 'financial', 'customer', 'internal processes' and 'learning and growth', each of which is connected by cause-and-effect relationships that reflect the firm's strategy. Social aims of social enterprise are to accomplish desired outcomes which are to employ vulnerable people and to provide social services. The measurement factors of financial perspective are stable funding, efficiency of budgeting, stakeholders' financial supports, and trade profit. The measurement factors of customer perspective are government, social service users, employees, local communities, sup plier, social activity company, and partnership with external organizations. The measurement factors of internal process perspective are organizational culture, organizational structure/management, internal/external communication, quality of products and services, information sharing. The measurement factors of learning and growth perspective are training and development, management participation, knowledge sharing, leadership of CEO and manager, and learning culture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6203-6207
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• 2012

The aim of the study was to develop an objective measurement tool, which could measure radiation safety regulations as an advanced research to draw evidentiary conclusions for the rationalization of radiation safety regulations as organizations continuously increase consumption of radiation material. The survey was based on the contents of Vol 1~21 of US NRC NUREG 1556 (Consolidated Guidance About Materials Licenses) and material from the Nuclear Safety Act which was based on radiation safety managers who are responsible for about 10% of the domestic registered organizations for radiation usage. As a result of the analysis, 3 main causes were extracted based on 20 questions. Each causes were named as Cause 1: 'Radioactive Safety Regulations Requirements', Cause 2: 'Compatibility of Actual Safety Regulation', and Cause 3: 'RI/RG radiation Source Classification' respectively. The dispersal explanations of each causes were explained in total of 60.417% by 40.140% of Cause 1, 13.721% of Cause 2, and Cause 3 for 6.556% If radiation safety regulation standards are drawn using the radiation safety regulation measurement tool, which is suggested in this study, this could be not only comply with international standards but also could be used to propose a practical standard to domestic radiation safety managers.

• The Mathematical Education
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• v.56 no.4
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• pp.407-434
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• 2017

The purpose of this study is to develop and verify the TPACK measurement tool for middle and high school mathematics teachers in the Korean context. Also, by clarifying the relationship between subordinate factors of Mathematics teachers' TPACK, an attempt was made to provide suggestions on the designs and directions for the in-service and pre-service teacher education and the programs for improving mathematics teachers' TPACK in the future. In order to achieve this goal, TPACK factors of mathematics teachers were extracted by reviewing literature on PCK, MKT, and TPACK. Then, content validity, basic statistical survey, reliability verification, exploratory factor analysis, confirmatory factor analysis, and structural equation model verification were conducted sequentially. At first, preliminary analysis was carried out on 79 mathematics teachers, and 76 items excluding the items with extreme value and reliability were included in the basic statistical analysis. And secondly, an exploratory factor analysis was conducted on 376 mathematics teachers, and this instrument consisted of 7 subordinate factors(CK, PK, TK, PCK, TCK, TPK, TPACK) and 61 items. Also by conducting confirmatory factor analysis and structural equation model test with 254 mathematics teachers, the measurement tool was confirmed the validity and reliability through statistically significant analysis. Then, the importance of integrated knowledge was confirmed by looking at the relationship between the TPACK factors of in-service mathematics teachers. The integrated knowledge(PCK, TCK, TPK) has played a crucial role in the formation of TPACK rather than the knowledge of CK, PK, and TK alone. Finally, the validity of TCK was confirmed through the structural equation modeling of TPACK. TCK not only directly affected TPACK, but also indirectly through TPK. According to these affirmative results, this measurement tool is claimed to be suitable for measuring the factors of Mathematics teachers' TPACK, and also the structural equation model can be regarded as a suitable model for analyzing the structural relationship of mathematics teachers' TPACK.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.355-359
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• 2019

Schirmer test is one of the most used methods for the diagnosis of dry eye. We attempted to develop a tear level measurement tool to replace unreliable Schirmer test with inaccurate results. Absorbency tests for various absorbents were carried out. As a result, ${\alpha}$ cellulose pulp was selected as the absorbent. Prototypes were produced and evaluated twice. Finally a tear level measurement tool in the form of a strip of ${\alpha}$ cellulose pulp adhered to a polyurethane was prepared. Usability evaluation of prepared tear level measurement tool was performed. As a result, it was confirmed that it has a significant correlation with SM tube developed oversea recently. In addition, it was judged to be useful as an alternative to the Schirmer test in terms of measurement time and accuracy.

• Journal of The Korean Association For Science Education
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• v.38 no.5
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• pp.753-763
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• 2018

The image of scientists that learners have has an important impact on science learning and on science-related career choices. The image of the scientist was mainly analyzed using the drawing analysis method. Drawing analysis has limitations on drawing, mainly analyzing the external image of scientist. Science teachers' images of scientists and their perception of science-related careers are important factors in students' science learning and science-related career choices. However, research on science teachers is lacking. Therefore, the purpose of this study is to investigate the usefulness of measurement tools by developing and applying a scientist image measurement tool through the semantic analysis method, and to discuss the educational implications of the research by investigating the image of scientists and science-related professions of secondary pre-service science teachers. The subjects of the study were 79 male and 55 female for a total of 134 students in the 2nd and 3rd grades majoring in science education at a teachers college. The results of the research show that the image measurement tool consisted of four components: 'ability,' 'evaluation,' 'activity,' and 'emotion,' in 24 items. As a result of applying the developed measurement tool to the secondary pre-service science teachers, the image of the 'evaluation,' 'ability,' and 'activity' elements of the scientist were high, but 'emotion' was low. There was no statistically significant difference according to gender. It is found that science-related career perceive them as 'hard,' 'professional,' 'smart,' and 'complex.' In particular, male students perceive themselves as 'hard and difficult' while female students perceive it as 'challenging and complicated'. Finally, we discussed the usefulness of using the image measurement tool of the scientists, the image of the scientists of the secondary pre-service science teachers, and the educational implications on science-related career.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.880-883
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• 2006

The reduction of tool vibration has been a serious issue for both employers and workers because of the risks of vibration transmitted to the workers. In this study a hand-arm vibration measurement and evaluation system was developed based on ISO 5349:2001 and used for analyzing relation of vibration level and components of tools. This system consists of a notebook PC installed a LabVIEW program and the data acquisition system including two 3-axial accelerometers and a NI-DAQ card. Vibration measurement tests were conducted for eight angle grinders and four impact wrenches where 3 subjects were used for each of the tools. The relation between different components of each tool and its vibration total value made it possible to set-up a guideline of tool design. In the past engineers developed tools by using their experience and intuition, but by using this system it became possible to design tool components so as to minimize the risks of hand-transmitted vibration.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.1
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• pp.1-9
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• 2001

The development of flexible automation in the manufacturing industry is concerned with production activities performed by unmanned machining system A major topic relevant to metal-cutting operations is monitoring toll wear, which affects process efficiency and product quality, and implementing automatic toll replacements. In this paper, the measurement of the cutting force components has been found to provide a method for an in-process detection of tool wear. The static com-ponents of cutting force have been used to detect flank wear. To eliminate the influence of variations in cutting conditions, tools, and workpiece materials, the force modeling is performed for various cutting conditions. The normalized force dis-parities are defined in this paper, and the relationships between normalized disparity and flank were are established. Final-ly, artificial neural network is used to learn these relationships and detect tool wear. According to proposed method, the static force components could provide the effective means to detect flank wear for varying cutting conditions in turning operation.