• International Journal of Precision Engineering and Manufacturing
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• v.9 no.4
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• pp.3-10
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• 2008

Micro-electrical discharge machining (micro-EDM) is an effective method for machining all types of conductive materials regardless of hardness. Since micro-EDM is an electro-thermal process, the energy supplied by the pulse generator is an important factor in determining the effectiveness of the process. In this study, an investigation was conducted on the micro-EDM of tungsten carbide (WC) to compare the performance of transistor and resistance/capacitance (RC) pulse generators in obtaining the best quality micro-hole. The performance was measured by the machining time, material removal rate, relative tool wear ratio, surface quality, and dimensional accuracy. The RC generator was more suited for minimizing the pulse energy, which is a requirement for fabricating micro-parts. The smaller-sized debris formed by the low-discharge energy of RC micro-EDM could be easily flushed away from the machined zone, resulting in a surface free of burrs and resolidified molten metal. The RC generator also required much less time to obtain the same quality micro-hole in WC. Therefore, RC generators are better suited for fabricating micro-structures, producing good surface quality and better dimensional accuracy than the transistor generators, despite their higher relative tool wear ratio.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.1
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• pp.15-24
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• 2007

This paper attempts to identify empirically whether the certification of Quality Management System affects positively to firm performance using the sample sets of 200 SMEs in Korea who have adopted ISO 9000 majoring in the domestic markets as well as the overseas markets. The empirical study has been done on the assumptions and the hypothesis that the certification itself can conceptually and practically be considered an effective tool to improve the level of standardization of quality management system, and it would result in higher productivity and good corporate image by enabling firms to strengthen up their capabilities to achieve competitive advantage. The empirical findings show that the ISO 9000 has positively contributed to not only obtaining competitive advantage but also bringing about a superior firm performance as it would be, making sure that the certification itself would be used as a powerful tool for good management. This study also pinpoints that the success/failure in introducing & adopting the certification depends highly upon the managers' interests and concerns, especially the CEO's.

• Journal of Korean Clinical Nursing Research
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• v.14 no.1
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• pp.33-44
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• 2008

Purpose: This study was performed to determine the effects of foot reflexology on pain and quality of sleep in patients with terminal cancer. Method: Quai-experimental research design was used. The subjects of this study were consisted of 19 for experimental group and 18 for control group. Visualue Scale(VAS) was used as the measurement tool of pain in this study, Verra & Snyder-Halpern Sleep Scale(VSH) and Visual Analogue Scale(VAS) were used as the measurement tool of perceived quality of sleep. Data were analyzed using statistical methods such as frequency, percent, $x^2$-test, t-test using SPSS WIN 12.0 program. Results: The hypothesis 1 that the experimental group with reflexology has less degree of pain than the control group without reflexology was supported (t=5.41, p<.001). The hypothesis 2 that the experimental group with reflexology has higher degree of VSH Scale than the control group without reflexology was supported(t=2.37, p=.02). The hypothesis 3 that the experimental group with reflexology has the difference among the mean of sleep VAS Scale during the 12 measurement periods was not supported(F=1.63, p=.08), and no significant interactions between group and time. Conclusion: It is considered that reflexology is effective for reducing cancer pain and improving quality of sleep in patients with terminal cancer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.1
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• pp.63-68
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• 2002

In this paper harmonic diagnose tool is described for electric evaluate the power quality at industrial power systems is described both simulation and experimental testing during various operation conditions. PTW (Power Tools for Windows) and harmonic measuring instrument are organized around personal computer and/or instrumentation study environments interconnected via RS-232. Unknown zero sequence impedance data of cable is calculated by the modified T&D and BICC method. IEEE standard is also used to estimate the transformer input data. the proposed system provides a flexible and effective environment to diagnose the power quality at industrial distribution systems by utilizing simulations and actual field data.

• Korean Journal of Occupational Health Nursing
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• v.28 no.1
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• pp.21-35
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• 2019

Purpose: The purpose of this study is to propose directions for the development of Occupational Health Nursing Intervention by identifying the current status and quality of Occupational Health Nursing Intervention Research in domestic industries. Methods: Between 2000 and August of 2018, total of 1,181 Occupational Health Nursing related published references were searched using 4 domestic databases, and of the total, 29 final theses that suited the requirements were analysed In this research, the quality assessment of literature that were selected as suitable was conducted using a tool for assessing the biasing risk of non-randomized studies, RoBANS(Risk of Biasing Assessment Tool for Non-randomized Study). Results: For all research, nonequivalent control group pre-posttest design was the most used as quasi-experimental designs. The effectiveness of intervention was found both in terms of physical and psychological aspects, and the result of the risk of biasing assessment showed a high risk levels in both "confounding variables" and "detection bias". Conclusion: Occupational Health Nursing Intervention have been steadily making improvements in terms of both quality and quantity, and as for more effective intervention developments that improves the physical and mental health of the workers, supplementation in strict research design and in ethical aspects deems necessary.

• Journal of Internet Computing and Services
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• v.23 no.2
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• pp.79-86
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• 2022

This paper focuses on realizing design improvement and high quality through visualization of reverse engineering-based software. As new technologies and complex software emerge in various areas of the fourth industry in the future, software verification with both stability and reliability is becoming an issue. We propose a reverse engineering-based UML design extraction and visualization for high-quality software ranging from simple computational software to machine learning-based data-oriented software. Through this study, it is expected to improve software quality through design improvement by checking the accuracy of the target design and identifying the code complexity.

• Transactions of Materials Processing
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• v.32 no.5
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• pp.247-254
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• 2023

This study conducted the wear tests on bending punches coated with PVD CrN and examined the surface quality of the product formed by each punch in the forming of uncoated TRIP1180 sheets. The study quantitatively estimated the surface quality of the product by measuring the roughness and imaging the product surface. The correlation between the punch wear depth and the product surface roughness was quantitatively analyzed. The results showed that before failure occurs, the product roughness was comparable with that of the as-received, and the product surface was smooth without scratches and defects. However, after failure, the punch wear is caused by fretting wear mechanism, and a punch whose coating is not completely peeled plows the product surface, resulting in severe scratches with grooves and ridges on the product surface. Severe wear on the punch surface caused by fretting wear can rapidly degrade the product surface quality as it is directly affected by the punch surface condition, and the product surface quality accurately reflects the punch wear condition.

• Research in Community and Public Health Nursing
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• v.33 no.1
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• pp.114-127
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• 2022

Purpose: This study aimed to develop a self-management mobile app for adults with osteoarthritis based on a self-determination theory to use it as a nursing intervention tool, and to evaluate the effects of the developed mobile app on adults' basic psychological needs, indexes of osteoarthritis, self-management and quality of life. Methods: The 56 participants were randomly assigned to either the experimental group (n=28) or the control group (n=28). The participants of the experimental group used a self-management mobile app for 12 weeks after the pretest, and two posttests were taken at the end of every 6 weeks. The data were analyzed using IBM SPSS/WIN 25.0 for Chi-square test, Fisher's exact test, independent t-test, and repeated measures ANOVA. Results: Basic psychological needs, indexes of osteoarthritis, self-management, and quality of life score of the experimental group were significantly higher than those of the control group. Conclusion: Our findings suggest that mobile app intervention can support improvements in psychological needs, symptoms of osteoarthritis and quality of life in adults with osteoarthritis. It is recommended that the developed mobile app be used as a nursing intervention tool for adults with osteoarthritis in the community.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.4
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• pp.39-47
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• 2004

In mold machining, there are many concave machining regions where chatter and tool deflection occur since MRR(material removal rate) increases as curvature increases even though cutting speed and depth of cut are constant. Boolean operation between stock and tool model is widely used to compute MRR in NC milling simulation. In finish cutting, the side step is reduced to about 0.3mm and tool path length is sometimes over loom, so Boolean operation takes long computation time and includes much error if the resolution of stock and tool model is larger than the side step. In this paper, curvature of CL (cutter location) surface and side step of tool path is used to compute the feedrate for constant MRR machining. The data structure of CL surface is Z-map generated from NC tool path. The algorithm to get local curvature from discrete data was developed and applied to compute local curvature of CL surface. The side step of tool path was computed by point density map which includes cutter location point density at each grid element. The feedrate computed from curvature and side step is inserted to new tool path to regulate MRR. The resultants were applied to feedrate optimization system which generates new tool path with feedrate from NC codes for finish cutting. The system was applied to the machining of speaker and cellular phone mold. The finishing time was reduced to 12.6%, tool wear was reduced from 2mm to 1.1mm and chatter marks and over cut on corner were reduced, compared to the machining by constant feedrate. The machining time was shorter to 17% and surface quality and tool was also better than the conventional federate regulation using curvature of the tool path.

• Journal of the Korea Society of Computer and Information
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• v.15 no.11
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• pp.143-156
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• 2010

Faced with an increase of malicious threats from the Internet as well as local area networks, many companies are considering deploying a security system. To help a decision maker select a suitable security tool, this paper proposed a three-step integrated framework using linear fuzzy regression (LFR) and physical programming (PP). First, based on the experts' estimations on security criteria, analytic hierarchy process (AHP) and quality function deployment (QFD) are employed to specify an intermediate score for each criterion and the relationship among these criteria. Next, evaluation value of each criterion is computed by using LFR. Finally, a goal programming (GP) method is customized to obtain the most appropriate security tool for an organization, considering a tradeoff among the multi-objectives associated with quality, credibility and costs, utilizing the relative weights calculated by the physical programming weights (PPW) algorithm. A numerical example provided illustrates the advantages and contributions of this approach. Proposed approach is anticipated to help a decision maker select a suitable security tool by taking advantage of experts' experience, with noises eliminated, as well as the accuracy of mathematical optimization methods.