• KEPCO Journal on Electric Power and Energy
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• 제2권2호
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• pp.293-298
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• 2016

Recently, interests for maintenance of transmission tower are increasing to extend life of structures and reduce maintenance cost. However, existing classical diagnosis method of corrosion deteriorated degree on the transmission tower steel members, visual inspection, has a problem that error often due to difference of inspector's individual knowledge and experience. In order to solve the problem, this study carried out to develop the corrosion deterioration inspection tool for transmission tower steel members. This tool is composed of camera equipment and computer-aided diagnosis system. We standardized the photographing method by camera equipment to obtain suitable pictures for image processing. Diagnosis system was designed to evaluate automatically degree of corrosion deterioration for member of transmission tower on the basis of the RGB color image processing techniques. It is anticipated that developed the corrosion deterioration inspection tool will be very helpful in decision of optimal maintenance time for transmission tower corrosion.

• Journal of Information Technology Applications and Management
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• 제10권4호
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• pp.29-50
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• 2003

This research provide the basic information to enhance the user-orientedness of usability design guidelines for software products and an effective empirical guidance to classify design attributes of internet shopping mall sites. The results of analysis show that design attributes can be classified into the procedural attribute group, the shopping tool attribute group, the visual attribute group, linguistic attribute group, and others. The results show that shopping tool attribute group can be divided further into the search tool attribute group and purchase tool attribute group and that the visual attribute group can be divided further into the screen condition attribute group and the character legibility attribute group. The research reveals that when designers design software interfaces and features they should take the compound effect of a group of design attributes into consideration to enhance the usability of the system.

• 한국기계가공학회지
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• 제18권11호
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• pp.89-95
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• 2019

In this research, the effect of roughing on tool load through bottom-up machining is investigated through actual machining. Generally, through the use of high-speed machining technology, machining methods, such as general roughing, operate by deepening the cutting depth for as long as the tool is able to withstand it, giving a slower feed rate, less cutting depth, and faster feed. However, when the cutting depth is deep, there is a problem in that the stepped shape of the cutting area is increased (e.g., by the shaking of the tool or the chipping load). However, if the cutting is performed less, the cutting time becomes relatively long. To compensate for these drawbacks and extend the service life of the tool, economic efficiency needs to be secured.

• Educational Technology International
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• 제10권2호
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• pp.29-61
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• 2009

The purpose of this study was to design an inquiry supporting tool on wiki based collaborative learning and to investigate the effect of the inquiry supporting tool. Eight design principles were selected and more specified design strategies were made from the literatures. The first system with the first-round design principles was developed and implemented in an actual classroom. After the first field study, researcher found a few drawbacks of the system. The second system was implemented in the classroom again. Finally developed wiki-based inquiry supporting tool system is unique in that it allows instructors to design their own CSCL inquiry activities, and it has intuitive menu tabs showing inquiry learning processes.

• Design & Manufacturing
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• 제16권1호
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• pp.9-14
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• 2022

A lot of research is being done on metal materials to improve the lifespan of molded parts. As a result, excellent mold materials have been developed that withstand high hardness at high temperatures and frictional heat generated from high-speed cutting. In this study, the press mold life of powder high-speed tool steel and general high-speed tool steel was compared. Powdered high-speed steel is composed of alloying elements such as tungsten, maldividene, cobalt, chromium, and vanadium in steel, which improves wear resistance compared to high-hardness and high-speed tool steels. The mold parts of both steel types were manufactured in the same way from heat treatment to machining, and the powder high-speed tool steel was 66HRC and the high-speed tool steel was 61HRC. As a result of the experiment, it was observed that the number of punching of powder high-speed tool steel was improved by 40-50%, and powder high-speed tool steel had fewer impurities, uniform texture, and excellent surface structure. It has a microscopic structure.

• 임상간호연구
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• 제16권1호
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• pp.177-196
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• 2010

Purpose: This study was conducted to develop the nursing process based performance measurement tool and the evidence based care standards for nursing care in medication management and blood transfusion. Methods: The care standards and performance measurement tool were drafted through comprehensive review of relevant literature, national guidelines, hospital protocols, and standards of recognized international accrediting bodies. The proposed care standards and performance measurement tool were reviewed by the panel of experts and refined based on the panel's suggestions. Final care standards and performance measurement tool were validated by surveying the hospital nurses. Results: All items of the performance measurement tool for medication management and blood transfusion were evaluated appropriate. All contents of care standards and the measurable elements except the evaluation of discharge education were appropriate. The performance measurement tool developed in this study was found to be acceptable as a tool to evaluate quality of nursing care in medication management and blood transfusion. Conclusion: The outcomes of this study including the performance measurement tool and evidence based care standards would be the important indicators to monitor whether necessary nursing care is implemented and be the useful primary resources to improve quality of nursing care services.

• Tribology and Lubricants
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• 제39권3호
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• pp.118-122
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• 2023

In our study, we develop a finite element model based on Archard's wear law to predict the cumulative wear and the evolution of the tool profile in friction stir welding (FSW) applications. Our model considers the rotational and translational behaviors of the tool, providing a comprehensive description of the wear process. We validate the accuracy of our model by comparing it against experimental results, examining both the predicted cumulative wear and the resulting changes to the tool profile caused by wear. We perform a detailed comparison between the predictions of the model and experimental data by manipulating non-dimensional coefficients comprising model parameters, such as element sizes and time increments. This comparison facilitates the identification of a specific non-dimensional coefficient condition that best replicates the experimentally observed cumulative wear. We also directly compare the worn tool profiles predicted by the model using this specific non-dimensional coefficient condition with the profiles obtained from wear experiments. Through this process, we identify the model settings that yield a tool wear profile closely aligning with the experimental results. Our research demonstrates that carefully selecting non-dimensional coefficients can significantly enhance the predictive accuracy of finite element models for tool wear in FSW processes. The results from our study hold potential implications for enhancing tool longevity and welding quality in industrial applications.

• 정보관리학회지
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• 제24권3호
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• pp.219-244
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• 2007

본 연구는 참고정보원 관리도구를 데스크탑 기반, 웹 기반, 웹 2.0 기반의 세 가지 유형으로 구분하고, 각 유형에 대한 대표적인 도구를 선정하여 각 도구의 제공기능에 대한 비교 분석과 이용자 중심에서 사용성을 비교 평가하기 위한 것이다. 도구의 제공기능에 대한 조사를 위해 먼저 각 도구의 제공기능에 대한 비교분석을 수행하였다. 유형별 도구에 대한 사용성 평가는 실험 후 각 참고정보원 관리도구의 만족도, 이해 편리성, 적합성, 효율성에 대한 비교 연구로 진행하였으며, 정량적 연구방법과 정성적 연구방법을 병행하였다. 정량적 연구의 데이터 수집을 위한 조사도구로 설문조사를 사용하였으며, 정성적 연구는 각각의 실험자에 대한 면담을 통하여 그 내용을 분석하였다. 유형별 참고정보원 관리도구에 대한 사용성 비교 평가를 통해 얻어진 분석 결과는 다음과 같다. 첫째, 이용자 만족도의 평균값은 도구 B(웹 기반)가 가장 높았으며, 다음으로 도구 A(데스크탑 기반), 도구 C(웹 2.0 기반) 순으로 나타났다. 둘째, 이해 편리성은 도구 B, 도구 C, 도구 A 순으로 나타났다. 셋째, 적합성은 도구 A, 도구 B, 도구 C 순으로 나타났다. 넷째, 효율성은 도구 B, 도구 A, 도구 C 순으로 나타났다.

• Journal of Mechanical Science and Technology
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• 제18권5호
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• pp.770-779
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• 2004

This paper describes the micro cutting of wear resistant tungsten carbides using PCD (Poly-Crystalline Diamond) cutting tools in performance with SEM (Scanning Electron Microscope) direct observation method. Turning experiments were also carried out on this alloy (V50) using a PCD cutting tool. One of the purposes of this study is to describe clearly the cutting mechanism of tungsten carbides and the behavior of WC particles in the deformation zone in orthogonal micro cutting. Other purposes are to achieve a systematic understanding of machining characteristics and the effects of machining parameters on cutting force, machined surface and tool wear rates by the outer turning of this alloy carried out using the PCD cutting tool during these various cutting conditions. A summary of the results are as follows: (1) From the SEM direct observation in cutting the tungsten carbide, WC particles are broken and come into contact with the tool edge directly. This causes tool wear in which portions scrape the tool in a strong manner. (2) There are two chip formation types. One is where the shear angle is comparatively small and the crack of the shear plane becomes wide. The other is a type where the shear angle is above 45 degrees and the crack of the shear plane does not widen. These differences are caused by the stress condition which gives rise to the friction at the shear plane. (3) The thrust cutting forces tend to increase more rapidly than the principal forces, as the depth of cut and the cutting speed are increased preferably in the orthogonal micro cutting. (4) The tool wear on the flank face was larger than that on the rake face in the orthogonal micro cutting. (5) Three components of cutting force in the conventional turning experiments were different in balance from ordinary cutting such as the cutting of steel or cast iron. Those expressed a large value of thrust force, principal force, and feed force. (6) From the viewpoint of high efficient cutting found within this research, a proper cutting speed was 15 m/min and a proper feed rate was 0.1 mm/rev. In this case, it was found that the tool life of a PCD tool was limited to a distance of approximately 230 m. (7) When the depth of cut was 0.1 mm, there was no influence of the feed rate on the feed force. The feed force tended to decrease, as the cutting distance was long, because the tool was worn and the tool edge retreated. (8) The main tool wear of a PCD tool in this research was due to the flank wear within the maximum value of $V_{max}$ being about 260 $\mu\textrm{m}$.

• 한국재난정보학회 논문집
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• 제19권3호
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• pp.673-688
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• 2023

연구목적: 공사 중에 발생하는 화재는 빈도는 적으나 그 피해가 크다. 최근 물류유통산업의 성장으로 신축하는 물류창고의 공사장이 증가하고 있어 연구대상으로 선정하고 화재예방을 정량적으로 접근하기 위해 화재위험도 평가 Tool의 개발을 통해 공사현장의 재난을 줄이고자 연구를 진행하였다. 연구방법: 공정에서 진행되는 작업을 분류하여 연소의 3요소에서 제어가 어려운 공기(산소)를 제외한 가연물과 점화원을 등급별로 구분하고, 피난안전성을 추가로 대입하여 종합적인 화재위험평가 Tool을 객관적으로 정량화하여 정립하였다. 연구결과: 개발하여 제시한 화재위험도 평가 Tool을 이용하여 화재위험도가 낮은 굴착공사와, 화재위험도가 중간정도인 설비공사, 화재위험도가 높은 마감공사를 샘플링하여 결과값(CGI)을 도출하였다. 결론: 본 연구에서는 건설현장에서 화재발생 위험도를 평가할 수 있는 Tool의 개발로 위험도 평가에 따른 물적조건(가연물)과 에너지조건(점화원)을 제어하여 구체적인 예방대책의 수립과 피난안전성의 평가를 가능하게 하였다. 향후 건설현장의 화재위험도 평가Tool의 적용을 통해 위험을 줄일 수 있는 공정의 계획 수립과 소방설비의 적응성을 평가하는 기준으로 제공되길 기대한다.