• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.3
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• pp.56-62
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• 2014

During the hot forging process, the most common cause of tool failure is wear. Tool wear results in the gradual loss of part tolerances, after which eventually the tool must be replaced or repaired. In order to maximize the lifetimes of forging tools, it is important to investigate the wear mechanisms of these tools. In this study, the hot forging of the outer race of an automotive constant-velocity joint was analyzed by a finite element method to investigate the wear distribution, especially the amount and location of the maximum expected wear damage, using Archard's wear model, which was modified considering the forging temperature. Forging analyses were carried out after modifying blocker forging tools based on established versions. The modified blocker tools resulted in an increase in the tool life up to 31% with a finisher punch.

• Journal of Korean Clinical Nursing Research
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• v.16 no.3
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• pp.5-23
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• 2010

Purpose: This study was conducted to determine the validity and reliability of performance measurement tools based on the nursing process for prevention and management of pressure ulcers, falls and pain. Methods: The performance measurement tools were reviewed by a panel of experts and refined on the basis of the panel's suggestions. The validity of the performance measurement tools was measured by surveying hospital nurses. The reliability of these tools was tested by having nursing experts use the tools in five nursing units to assess nursing performance in prevention and management of pressure ulcers, falls and pain. Results: The performance measurement tools in this study were found to be acceptable as tools to evaluate quality of nursing care in pressure ulcers, falls and pain. The reliability of the performance measurement tools was acceptable. Conclusion: These results indicate that the performance measurement tools developed in this study are valid and reliable instruments to monitor and improve quality of nursing care in prevention and management of pressure ulcers, falls and pain.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.1
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• pp.99-108
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• 2012

The purpose of this study is to demonstrate the improvement of the education process in architectural engineering through the analysis of the advantages of the BIM tool. As public institutions and owners have been introduced to Building Information Modeling (BIM) tools, BIM has become an important factor in the design process in undergraduate university programs. First, BIM-related issues, domestic and overseas, was analyzed. Second, a case study of BIM education was analyzed at K University under the ABEEK process. Students participated a survey about the understanding of BIM and the use of BIM tools. As a result of the analysis, six advantages of the use of BIM tools were found. As a result of this research, following five issues are found about BIM education through advantage of using BIM tools. The result of this research was verified by conducting a survey on the usage of BIM softwares. The limitation of this study was to analyze the case study of only limited numbers of participants at the university.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.718-719
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• 2015

As a recent global trend, the majority of plant projects are delivered through EPC or EPC-turnkey contracts, where a contractor's liability is more complicated because of the mega size scale and financing method. Previous researches have been lacking a practical usability for project members for liabilities of contracts. Those were focused on solving the claims or schedule calculation issues only. The objective of the present study was to develop a validation process for LDs (liquidated damages) in contractor's liabilities with various case studies and expert judgments. As summarized in this paper, the processes and tools were developed with project life cycle process. The project preparation phase includes 3 step check lists to determine the Go or No-go for projects. In progress phase, contractors should focus on the response strategies for claims with liabilities. The study concludes that those developed processes and tools will help to manage risk of LDs for the contractors in the overseas projects.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.143-150
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• 2016

Modular house is built by assembling various joints. Module assembly in the stage of on-site installation is very important process, because assembly process directly affects the structural stability and the quality. However, manual tools and electric-powered tools have a problem in that assembly productivity and quality are reduced during long-time usage. Although pneumatic assembly tools for modular house have been developed, but empirical analysis to compare and evaluate the performance of tools has not been sufficient. This study compares and analyzes the assembly quality and productivity by applying existing assembly tools and new pneumatic tools to the field. The analysis results show that pneumatic assembly tools are more excellent in terms of assembly productivity and quality.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.633-636
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• 2005

Imprint lithography is a promising method for high-resolution and high-throughput lithography using low-cost equipment. As with other nanoimprint methods, ultraviolet-nanoimprint lithography (UV-NIL) resolution appears to be limited only by template resolution, and offers a significant cost of ownership reduction when compared to other next generation lithography (NGL) methods such as EUVL and 157 nm lithography. The purpose of this paper is to suggest optimum values of control parameters of Imprio 100 manufactured by Molecular Imprint, Inc., which is the first commercially available UV-NIL tool, for sound nanoimprint. UV-NIL experiments were performed on Imprio 100 to find dispensing recipe for avoiding air entrapment. Dispensing recipe related to residual layer thickness and uniformity was optimized and 40 nm thick residual layer was achieved.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.2
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• pp.20-26
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• 2012

Recently, micromilling process has been progressed to meet the variety of the industry demands in micromolds and precision components. As a result, more and more commercialized micro tools and machines become available during last few years. This paper reviews the recent progress of micromilling technology in last five years. The results in process, machine tools, and micro tool fabrications are discussed.

• Transactions of Materials Processing
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• v.19 no.1
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• pp.50-58
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• 2010

In order to successfully implement hot die forging process for the large-size titanium alloy products, it is necessary to devise a customized heating method for the billets and the die tools, as well as the die tool design. This study aims at establishing a hot die forging process of the large-size titanium alloy container products by applying the warm die, semi-hot die and hot die forging process step-wise. To accomplish this purpose, forging mechanism and the die tools were designed considering the strength of die materials at the given die heating temperature. The movable heating devices for the billet and the die tools were also introduced to prevent overcooling of billet and die tools. To verify the applicability of the designed forging process, real-size forging tests were carried out and the quality of forged products, including dimension, surface condition, microstructure and the mechanical properties was evaluated.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.545-562
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• 2019

The purpose of this study is to develop cognitive scaffolding tools and to explore their effects on integrated science process skills of high school students. For this purpose, we developed cognitive scaffolding tools including one kind of classroom instruction for training integrated process skills and two kinds of individual learning materials that students can selectively study according to their level of inquiry ability. In addition, we developed hypothetico-deductive inquiry tasks as a tool to investigate the level of students on the integrated process skills for pre-test and post-test respectively. In order to verify the effectiveness of the cognitive scaffolding tools, we conducted inferential statistics on the pre-and post-tests of the experimental group and control group to examine statistical significance of students' inquiry level change depending on the usage of the cognitive scaffolding tools. We also produced Wrightmaps based on Rasch model to compare the change of inquiry ability depending on usage of the cognitive scaffolding tools. As a result, the experimental group using the cognitive scaffolding tools showed a significantly higher scores in all the components of integrated process skills namely, designing inquiry, collecting data, analyzing data, and forming conclusion than the control group. In addition, students who used cognitive scaffolding tools improved their inquiry ability and showed a distinct transition to higher level in each component of the integrated process skills. The results of this study suggest that high school students need cognitive scaffolding to alleviate or eliminate the functional barriers they face in conducting scientific inquiries.

• Journal of Korean Institute of Industrial Engineers
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• v.15 no.2
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• pp.45-55
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• 1989

This paper deals with development of a computer-aided process selection and sequencing technique and its software for metal cutting processes of rotational parts. The process selection procedure consists of selection for proper machining operations and machine tools suitable for the selected operations. Machining operations are selected based on machining surface features and machine tools are selected by employing a conversion table which converts machining operations into machine tools. The process sequence is determined by the proper manipulation of the precedence relation matrix. A computer program for the proposed technique is developed by using Turbo-Pascal on IBM PC/AT compatible system. The proposed technique works well to real problems.