• 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.

• Journal of the Korean Society for Library and Information Science
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• v.38 no.2
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• pp.213-238
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• 2004

Book review Is a mean that provides Qualitative evaluation and at the same time it plays a role as selection tools for libraries. Therefore, this study Identified various media providing reviews on children's books, evaluated whether the reviews in the media were useful as selection tools of current books, and a desirable model for the book review media that would reform the existing problems was suggested. The efforts to make up for the above suggestions are needed, so that the current children's book review media can properly play a role as selection tools. Above all, at this point in time, it is necessary to publish review media made in the view of libraries and librarians.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.8
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• pp.683-689
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• 2016

Servo mismatch, which affects positioning accuracy of multi-axis machine tools, is usually estimated via the circular test. However, due to mechanical restrictions in measuring instruments, the circular test using a double ball-bar is difficult to apply in miniaturized or super-large sized machine tools. Laser trackers are widely used to measure the form accuracy of parts and the positioning accuracy of driving systems. In this paper, a technique for the servo mismatch estimation of multi-axis machine tools is proposed via the circular test using a laser tracker. To verify the proposed technique, experiments using a double ball-bar and laser tracker are conducted in a 3-axis machine tool. The difference in the evaluation results is 0.05 msec. The servo mismatch for the miniaturized machine tool is also evaluated using the proposed technique.

• Korean Journal of Materials Research
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• v.30 no.12
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• pp.672-677
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• 2020

Expensive PCBN or ceramic cutting tools are used for the processing of difficult-to-cut materials such as Ti and Ni alloy materials. These tools have a problem of breaking easily due to their high hardness but low fracture toughness. To solve this problem, cutting tools that form various coating layers are used in low-cost WC-Co hard material tools, and researches on various tool materials are being conducted. In this study, WC-5, 10, and 15 wt%Ni hard materials for difficult-to-cut cutting materials are densified using horizontal ball milled WC-Ni powders and pulsed current activated sintering method (PCAS method). Each PCASed WC-Ni hard materials are almost completely dense, with a relative density of up to 99.7 ~ 99.9 %, after the simultaneous application of pressure of 60 MPa and electric current for 2 min; process involves almost no change in the grain size. The average grain sizes of WC and Ni for WC-5, 10, and 15 wt%Ni hard materials are about 1.09 ~ 1.29 and 0.31 ~ 0.51 µm, respectively. Vickers hardness and fracture toughness of WC-5, 10, and 15 wt%Ni hard materials are about 1,923 ~ 1,788 kg/mm2 and 13.2 ~ 14.3 MPa.m1/2, respectively. Microstructure and phase analyses of PCASed WC-Ni hard materials are performed.

• 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.

• IEMEK Journal of Embedded Systems and Applications
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• v.19 no.2
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• pp.83-90
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• 2024

CNC tools contribute to the production of high-precision and consistent results. However, employing damaged CNC tools or utilizing compromised numerical control can lead to significant issues, including equipment damage, overheating, and system-wide errors. Typically, the assessment of external damage to CNC tools involves capturing a single viewpoint through a camera to evaluate tool wear. This study aims to enhance existing methods by using only a single manually focused Microscope camera to enable comprehensive external analysis from multiple perspectives. Applying the NeRF (Neural Radiance Fields) algorithm to images captured with a single manual focus microscope camera, we construct a 3D rendering system. Through this system, it is possible to generate scenes of areas that cannot be captured even with a fixed camera setup, thereby assisting in the analysis of exterior features. However, the NeRF model requires considerable training time, ranging from several hours to over two days. To overcome these limitations of NeRF, various subsequent models have been developed. Therefore, this study aims to compare and apply the performance of Instant NGP, Mip-NeRF, and DS-NeRF, which have garnered attention following NeRF.

• Therapeutic Science for Rehabilitation
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• v.11 no.2
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• pp.7-24
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• 2022

Objective : To develop standardized assessment tools that evaluate the multi-aspect lifestyles of children and adolescents, we aimed to systematically analyze lifestyle assessment tools and lifestyle component-specific assessment tools. Methods : The study period was 2001-2020, with search engines using CINANL, NDSL, PubMed, and RISS. Search key words used 'lifestyle assessment' OR 'lifestyle profile' OR 'lifestyle test', 'physical activity assessment' OR 'physical activity participation profile', 'nutrition assessment' OR 'nutrition profile', 'activity participation assessment' OR 'activity participation profile'. Results : A total of 24 evaluation tools were selected after 5,883 studies reviewed the title, abstract, and full text after deduplication. The detailed results resulted in five lifestyle assessment tools, seven physical activity assessment tools, nine nutrition assessment tools, and three activity participation assessment tools. Conclusion : For the lifestyle assessment tools for children and adolescents, the component items, measurement methods, and age of assessment of each item were analyzed. It is hoped that this will be used as a basis for the development of standardized assessment tools to assess the multi-aspect lifestyles of children and adolescents in the future.

• Journal of Families and Better Life
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• v.28 no.3
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• pp.27-41
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• 2010

In this study, based on the current curriculum of consumer education in high school with the advent of Web 2.0 age, I analyzed both the curriculum used by new information tools related with Web 2.0 age and the one used by traditional tools to find out the degree of necessity of consumer education for the high school students in proportion to the level of their informational ability. First, compared with the education of food, clothes and shelter in the curriculum of manual training and domestic science, the necessity, importance, and availability were low and the students had a lower level of interest than they had with the three factors mentioned above. Second, after dividing the sector of consumer education in the curriculum into three fields such as reasonable purchase and use, solution and prevention of consumer problems and forming a new consumer trend, I looked into the necessity of the teaching method using conventional tools and the one using new informational tools following Web 2.0 age respectively. Traditional tools were favored for the education of consumption-related laws and policies, consumers' rights for the general cause of consumer problem solving and preventing. For the generation of the new comsumer trend, the new information tools were preferred in the appreciation of consuming culture and the issues of consuming environment. Third, it was revealed that students' level of informational ethics was the highest at 5.55 while their level of information creation and processing was the lowest at 3.96 from the research of six categories of their informational ability.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.3
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• pp.165-176
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• 2011

In this paper, we examine the reliability verification procedure of evidence analysis tools for computer forensics and test the famous tools for their functional requirements using the verification items proposed by standard document, TIAK.KO-12.0112. Also, we carry out performance evaluation based on test results and suggest the way of performance improvement for evidence analysis tools. To achieve this, we first investigate functions that test subjects can perform, and then we set up a specific test plan and create evidence image files which contain the contents of a verification items. We finally verify and analyze the test results. In this process, we can discover some weaknesses of most of analysis tools, such as the restoration for deleted & fragmented files, the identification of the file format which is widely used in the country and the processing of the strings composed of Korean alphabet.

• Journal of the Korean Society for information Management
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• v.24 no.3
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• pp.219-244
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• 2007

Reference resources management tools can be divided into three types: Desktop-based, Web-based, and Web 2.0-based. This study is intended to compare and analyze the functions provided by the three types of tools and also to compare and evaluate their usability. Each Tools were chosen to represent each type. For comparison and analysis of the functions provided by the three types of tools, we divided the process of using reference resources management tools into four steps and then compared and analyzed sub items in each step. Satisfaction, understandability, conformance and efficiency that items for comparison and evaluation of the usability were compared using both quantitative and qualitative approaches. We surveyed the participants to collect data for quantitative research; and interviewed them and analyzed the results for qualitative research. Here are the results from evaluating the usability of Tool A(Desktop-based), B(Web-based), C(Web 2.0 based). First, Tool B had the highest mean user satisfaction, followed by Tool A and Tool C. Secondly, Tool B had the lead in understandability, followed by Tool A and Tool C. Thirdly, Tool A had the highest mean conformance, followed by Tool B and Tool C. Fourth, Tool B had the highest mean efficiency, followed by Tool A and Tool C.