• 문화기술의 융합
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• 제5권1호
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• pp.389-394
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• 2019

본 연구에서는 무도상 궤도가 부설된 국내 도시철도의 철도 교량상 목침목에 대한 선로검사내규의 점검사항 및 불량판정 기준을 개선하여 목침목의 손상유형에 따른 상태등급체계를 분류하고 침목별 이력관리대장 시스템 도입을 통해 목침목의 유지관리체계를 개선하고자 하였다. 이를 위해 본 연구의 대상 철도교량에 부설되어 있는 목침목의 손상현황을 분석하여 손상별 코드를 구축하였으며, 침목별 손상 및 유지관리이력을 관리할 수 있는 유지관리시스템 도입을 통해 단면형상 및 침목 고정장치가 다양하고 유지관리가 복잡한 무도상 철도교량상 목침목의 체계적인 유지관리가 가능할 것으로 판단되었다.

• 한국사회복지학
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• 제58권1호
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• pp.209-235
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• 2006

이 연구는 우리나라 사회복지사의 수행 직무 특성을 고찰하고 사회복지사 1급과 2,3급의 직무유형을 제시하기 위하여 911명의 사회복지사를 대상으로 직무의 수행 빈도와 직무수준을 조사하였고, 이 두 가지 요소를 함께 고려하여 1급과 2,3급의 직무를 유형화하였다. 사회복지사의 수행 직무 특성으로는 시설관리, 직접 서비스 제공, 접수, 문서관리 등 수준이 낮게 인식된 직무의 수행 빈도가 높은 반면, 인력관리, 기획 및 재정관리 등의 행정적 직무와 업무형성과 유지, 평가 및 종결 등 수준이 높게 인식된 직무의 수행 빈도는 낮게 나타났다. 직무유형에 대안 분석 결과, 85개의 요소업무 중 유형 I의 업무(1급 사회복지사의 수행업무)는 53개였으며, 유형IV의 업무(2,3급 사회복지사의 수행업무)는 11개로 분류되었다. 또한 1급이나 2,3급이 실천현장이나 분야의 특성에 따라 탄력적으로 수행할 수 있는 업무유형 II, III의 업무는 31개가 제시되었다. 이 연구는 사회복지사 급수별 직무를 제시함으로써, 직무 할당의 근거로 활용하고 그에 따른 전문적 서비스를 제공하기 위함인데, 직무 할당이 급수별로 보다 명확하게 이루어지기 위채서는 현행 사회복지사 자격 제도가 함께 정비되어져야 한다. 이 연구가 자격제도 정비의 근거로 활용되고, 책임 있는 사회복지서비스의 제공근거로 활용되길 바란다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.184-190
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• 2009

Recently, the concern for the reliability of railway is increasing, also the study about reliability is being processed at a good pace. However, in case of an existing railway operating it is true that the railway system is being operated without a clear RAM standard. There is not a clear RAM standard about product menual of a city railroad, and there are only basic provisions concerning traction motor which can be called a main equipment. In this paper, we calculated the availability and reliability of subway having MKBSF, MKBF, MTBF, MTTR analyzing accumulated maintenance data about a main equipment of a VVVF direct subway being operated in line #4. By watching the reliability grade of a VVVF subway being operated and manufactured within the country and being applied with the development of a city railway reflected by RAM menual when the new subway is manufactured, and with the basic data of RCM, we'd like to grope the methods which can be improved by operation stability of a city railway.

• 한국구조물진단유지관리공학회 논문집
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• 제3권2호
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• pp.155-160
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• 1999

Recently, the study on mix design of lightweight concrete using the polystyrene foam balls is put into practice from the viewpoint to grade up the quality of concrete and recyclable usage of industrial by products. Polystyrene aggregate concrete, PAC, can be used as structural concrete in low strength application. For instance, PAC could be used in the middle part of sandwich panel where stresses are generally low and in the case of grid-type reinforcement where it does not need high bond strength but little compressive strength to resist the pressure of transverse reinforcement. From this point of view, the authors discussed the influence of fluidity and compressive strength of concrete by the difference of the volume percentage of polystyrene foam balls and water cement ratio.

• 임상간호연구
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• 제22권2호
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• pp.238-247
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• 2016

Purpose: This study was done to develop an evidence-based practice guideline for catheter dysfunction in hemodialysis patients. Methods: Development of the guideline process was done according to the De Novo development version 1.0 by NECA which consists of 12 steps. Results: The developed guideline consisted of 5 domains and 14 recommendations. The number of recommendations for each domain were: 3 on catheter dysfunction assessment, 1 on conservative management of catheter dysfunction, 7 on drug management of catheter dysfunction, 1 on catheter function test and 2 on maintenance management. Of the recommendations, 7.15% were marked as A grade, 52.85% of B grade, and 50% of C grade. Conclusion: Findings in this study indicate that this guideline can be added to the evidence-based practice guidelines for fundamentals of practice and that this guideline can be disseminated to nurses nationwide in order to improve the care of hemodialysis patients with catheter dysfunction.

• Tribology and Lubricants
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• 제38권1호
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• pp.22-26
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• 2022

A 1.7-ton grade small excavator is a construction equipment that can perform various functions in limited spaces where heavy equipment cannot enter easily. Owing to the recent acceleration of urbanization, it has been used increasingly in drainage and gas pipes, as well as for road repair works in urban areas. The power train of a traveling reducer for a 1.7-ton grade small excavator utilizes a complex planetary gear system. Complex planetary gears are vital to the power train of a traveling reducer as it mitigates the fatigue strength problem. In the present study, the specifications of a complex planetary gear train are calculated; furthermore, the gear bending and compressive stresses of the complex planetary gears are analyzed to achieve an optimal design of the latter in terms of cost and reliability. In this study, the actual gear bending and compressive stresses of a planetary gear system are analyzed using a self-developed gear design program based on the Lewes and Hertz equation. Subsequently, the calculated specifications of the complex planetary gears are verified by evaluating the results with the data of allowable bending and compressive stress based on curves of stress vs. number of cycles of the gears.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권11호
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• pp.2945-2965
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• 2023

The laser inertial measurement unit is a precision device widely used in rocket navigation system and other equipment, and its quality is directly related to navigation accuracy. In the quality evaluation of laser inertial measurement unit, there is inevitably uncertainty in the index input information. First, the input numerical information is in interval form. Second, the index input grade and the quality evaluation result grade are given according to different national standards. So, it is a key step to transform the interval information input by the index into the data form consistent with the evaluation result grade. In the case of uncertain input, this paper puts forward a method based on probability distribution to solve the problem of asymmetry between the reference grade given by the index and the evaluation result grade when evaluating the quality of laser inertial measurement unit. By mapping the numerical relationship between the designated reference level and the evaluation reference level of the index information under different distributions, the index evidence symmetrical with the evaluation reference level is given. After the uncertain input information is transformed into evidence of interval degree distribution by this method, the information fusion of interval degree distribution evidence is carried out by interval evidential reasoning algorithm, and the evaluation result is obtained by projection covariance matrix adaptive evolution strategy optimization. Taking a five-meter redundant laser inertial measurement unit as an example, the applicability and effectiveness of this method are verified.

• 산업경영시스템학회지
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• 제17권32호
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• pp.145-154
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• 1994

In this paper, monitoring processor in a circuit switched network is considered. Monitoring processor monitors communication links, and offers a grade of service in each link to controller. Such an information is useful for an effective maintenance of system. Two links with nonsymmetric system Parameters are considered. each link is assumed independent M/M/1/1 type. The Markov process is introduced to compute busy and idle portions of monitoring processor and monitored rate of each link. Inter-idle times and inter-monitoring times of monitoring processor between two links are respectively computed. A recursive formula is introduced to make computational procedure rigorous.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.130-136
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• 1999

The management method of the irrigation facilities are different with management agency , type, user, purpose of use, and the accuracy of data applied for the grasp of present situation and maintenance is of a low grade. Therefore the information management system is needed to classify and systematize the data. The purpose of this study is to prepare the digital map of Chonbuk FLIA district, to construct the database of the irrigation facilities , to develop the information system for the management using World Wide Web, to supply and be able to use easily to whomever needs it.

• 한국안전학회지
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• 제8권4호
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• pp.139-148
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• 1993

Thermosyphons are simple devices that can passively transport thermal energy over relatively long distance with little temperature degradation. These attributes permit the use of low grade thermal energy for thermal control of structures including the snow melting and deicing to the pavement surface. The thermosyphon system requires no costly energy input and Is completely maintenance free. This paper presents the experimental results of the snow melting system in which thermosyphon was utilized to transfer the geothermal energy to the pavement to obviate slipping traffic accidents due to freezing of pavement in winter.