• Environmental Engineering Research
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• v.8 no.1
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• pp.1-7
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• 2003

• 월간산업보건
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• s.347
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• pp.22-25
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• 2017

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.861-862
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• 2011

• Steel and Composite Structures
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• v.34 no.5
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• pp.681-698
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• 2020

The paper addresses contribution to the modeling and optimization of major machinability parameters (cutting force, surface roughness, and tool wear) in finish dry hard turning (FDHT) for machinability evaluation of hardened AISI grade die steel D₃ with PVD-TiN coated (Al₂O₃-TiCN) mixed ceramic tool insert. The turning trials are performed based on Taguchi's L₁₈ orthogonal array design of experiments for the development of regression model as well as adequate model prediction by considering tool approach angle, nose radius, cutting speed, feed rate, and depth of cut as major machining parameters. The models or correlations are developed by employing multiple regression analysis (MRA). In addition, statistical technique (response surface methodology) followed by computational approaches (genetic algorithm and particle swarm optimization) have been employed for multiple response optimization. Thereafter, the effectiveness of proposed three (RSM, GA, PSO) optimization techniques are evaluated by confirmation test and subsequently the best optimization results have been used for estimation of energy consumption which includes savings of carbon footprint towards green machining and for tool life estimation followed by cost analysis to justify the economic feasibility of PVD-TiN coated Al₂O₃+TiCN mixed ceramic tool in FDHT operation. Finally, estimation of energy savings, economic analysis, and sustainability assessment are performed by employing carbon footprint analysis, Gilbert approach, and Pugh matrix, respectively. Novelty aspects, the present work: (i) contributes to practical industrial application of finish hard turning for the shaft and die makers to select the optimum cutting conditions in a range of hardness of 45-60 HRC, (ii) demonstrates the replacement of expensive, time-consuming conventional cylindrical grinding process and proposes the alternative of costlier CBN tool by utilizing ceramic tool in hard turning processes considering technological, economical and ecological aspects, which are helpful and efficient from industrial point of view, (iii) provides environment friendliness, cleaner production for machining of hardened steels, (iv) helps to improve the desirable machinability characteristics, and (v) serves as a knowledge for the development of a common language for sustainable manufacturing in both research field and industrial practice.

• Journal of The Korean Association of Information Education
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• v.16 no.1
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• pp.107-121
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• 2012

The purpose of this study is to develop online synchronous discussion tool based on De Bono's six thinking hats and to investigate availability and improvements of the tool. Analysis of previous studies about synchronous online discussion and six thinking hats and development of design strategies from 3C model, communication, coordination, cooperation, were done. Six thinking hats online synchronous discussion tool was developed and applied four times for 5 weeks in the 'fundamentals of computer science' course of college students majored in computer science. Qualitative data from open-ended survey and reflection paper of students, and field note of participant researchers were analyzed. As a result, six thinking hats online synchronous discussion tool facilitated student's interaction and communication in the aspect of communication, coordination, and cooperation of 3C model. However, some improvements are needed to overcome the limits of text-based online communication and to use six thinking hats online synchronous discussion tool as a tool to promote structured interaction and communication.

• Journal of KIISE
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• v.43 no.5
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• pp.569-578
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• 2016

The PLC (Programmable Logic Controller) has been widely used for the development of digital control system of nuclear power plant. The PLC has high maintenance costs and increasing complexity, hence, FPGA (Field Programmable Gate Array) based digital control system has been considered as an alternative. However, the development of FPGA based digital control system is a challenge for PLC engineers because they are required to learn about new language to develop FPGA and knowledge and know-how acquired in the development of PLC is not transferable. In this study, we proposed and implemented an automatic translation tool for translation of FBD (Function Block Diagram), a programming language of PLC software, into VHDL (VHSIC Hardware Description Language). Automatically translating the FBD to VHDL using this tool allows PLC engineers to develop FPGA without any knowledge of the hardware description language.

• Journal of the Korea Society of Computer and Information
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• v.25 no.7
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• pp.143-150
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• 2020

Recently, many companies are interested in smart factory services. Because various smart factory services are provided by the combination of mobile devices, cloud computing, and IoT services. However, many workers turn away from these systems because most of them are not implemented from the worker's point of view. To solve this, we implemented a development tool that allows field workers to produce their own services so that workers can easily create smart factory services. Manufacturing data is collected in real time from sensors which are connected to manufacturing facilities and stored within smart factory platforms. Implemented development tools can produce services such as monitoring, processing, analysis, and control of manufacturing data in drag-and-drop. The implemented system is effective for small manufacturing companies because of their environment: making various services quickly according to the company's purpose. In addition, it is assumed that this also will help workers' improve operation skills on running smart factories and fostering smart factory capable personnel.

• Korean Journal of Community Nutrition
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• v.8 no.3
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• pp.319-326
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• 2003

The purposes of this study were: a) to develop the a quality measurement tool for the contract-managed hospital foodservice, and b) to evaluate their performance with the developed quality measurement tool, and c) to verify the reliability and validity of the quality measurement tool. The developed quality measurement tool comprised two parts, which were foodservice management and medical nutrition care service. The foodservice management part was classified into six functional categories which were Menu, Procurement and Storage, Production and Distribution, Facility and Utility, Sanitation and Safety, and Management and Evaluation. The medical nutrition care service part indicated the medical nutrition care provided. Quality measurement tool had 91 standards and 324 indicators. The quality measurement tools were distributed to the hospital foodservice manager employed by the foodservice company. The 324 indicators were measured by foodservice manager on the 5-Likert-type scales, and then adapted to a 100 point scale. The SPSS Ver. 11.0 was used for statistical analysis. The categories whose scores were evaluated as being high were Procurement', General Sanitation', Personal sanitation' and Waste' and the categories whose scores were evaluated as being low were Diet Order Manual', Standard Recipe', Appropriateness (Facility and Utility)', Check (Facility and Utility)'and Information Management'. All the categories of medical nutrition service were evaluated as having seriously low scores. Therefore, it was necessary for the contract-managed hospital foodservice to improve its performance in the area of medical nutrition care service. For the verification of the developed quality measurement tool, the reliability obtained by calculating Cronbach's α was 0.8747, and the content validity was also proved by scrutiny of the modification of the Professional group's techniques. (Korean J Community Nutrition 8(3) : 319∼326, 2003)

• Journal of Korean Academy of Nursing
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• v.42 no.5
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• pp.632-643
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• 2012

Purpose: This study was done to develop tool to evaluate the core competencies regarding nursing cancer patients on chemotherapy, and to verify the reliability and efficacy of the developed tool. Methods: A tool to evaluate the core competencies was developed from a preliminary tool consisting of 112 items verified by expert groups. The adequacy of the preliminary tool was analyzed and refined to the final evaluation tool containing 76 items in 8 core competencies and 18 specific competencies. The evaluation tool is in the form of a self-report, and each item is evaluated according to a 3-point scale. From September 22 to October 14, 2011, 349 survey responses were analyzed using SPSS 20.0 and the WINSTEPS program that employs the Rasch model. Results: Results indicated that there were no inappropriate items and the items had low levels of difficulty in comparison with the knowledge levels of the study participants. The results of factor analysis yielded 18 factors, and the reliability of the tools was very high with Cronbach's ${\alpha}$=.97. Conclusion: The results of this study can be used for training and evaluation of core competencies for nursing cancer patients, and for standardizing nursing practices associated with chemotherapy.

• Wind and Structures
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• v.18 no.2
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• pp.195-213
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• 2014

Recently, the horizontal axis rotor performance optimizer (HARP_Opt) tool was developed in the National Renewable Energy Laboratory, USA. This innovative tool is becoming more popular in the wind turbine industry and in the field of academic research. HARP_Optwas developed on the basis of two fundamental modules, namely, WT_Perf, a performance evaluator computer code using the blade element momentum theory; and a genetic algorithm module, which is used as an optimizer. A pattern search algorithm was more recently incorporated to enhance the optimization capability, especially the calculation time and consistency of the solutions. The blade optimization is an aspect that is highly dependent on experience and requires significant consideration on rotor control strategies, wind data, and generator type. In this study, the effects of rotor control strategies including fixed speed and fixed pitch, variable speed and fixed pitch, fixed speed and variable pitch, and variable speed and variable pitch algorithms on optimal blade shapes and rotor performance are investigated using optimized blade designs. The effects of environmental wind data and the objective functions used for optimization are also quantitatively evaluated using the HARP_Opt tool. Performance indices such as annual energy production, thrust, torque, and roof-flap moment forces are compared.