• 한국기계가공학회지
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• 제14권4호
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• pp.151-159
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• 2015

In this study, we developed an automated contact-type thickness measurement machine that continuously and precisely measures the thickness of a PCB module product using multi-LVDT sensors. The system contains a measurement part to automatically measure the thickness in real time according to the set conditions with an alignment supply unit and unloading unit to separate OK and NG products. The sensors were calibrated before assembly in the measuring machine, and precision and accuracy performance tests were also performed to reduce uncertainty errors in the measurement machine. In the calibration test, the precision errors of the LVDT sensor were determined to be $1-3{\mu}m$ as 0.1% at the measuring range. A measurement error of 0.8 mm and 1.0 mm thickness test standards were found to be $1{\mu}m$ and $4{\mu}m$, and the standard deviations of two 1.0 mm products were measured as $14{\mu}m$ and $8{\mu}m$, respectively. In the measurement system analysis, the accuracies of test PCB standards were found to be $2{\mu}m$ and $3{\mu}m$, respectively. From the results of gage repeatability and reproducibility (R & R) crossed, we found that the machine is suitable for the measurement and process control in the mass production line as 7.92% of total gage R & R and in seven distinct categories. The maximum operating speed was limited at 13 pcs/min, showing a value good enough to measure.

• 전기학회논문지
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• 제65권2호
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• pp.264-268
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• 2016

Recently, various energy efficiency optimization activities are ongoing globally by integrating conventional grids with ICT (Information and Communication Technology). In this sense, various smart grid projects, which power suppliers and consumers exchange useful informations bilaterally in real time, have been being carried out. The electric vehicle diffusion program is one of the projects and it has been spotlighted because it could resolve green gas problem, fuel economy and tightening environmental regulations. In this paper, the economics of V2G system which consists of electric vehicles and the charging infrastructure is evaluated comparing electric vehicles for V2G with common electric vehicles. Additional benefits of V2G are analyzed in the viewpoint of load leveling, frequency regulation and operation reserve. To find this benefit, electricity sales is modeled mathematically considering depth of discharge, maximum capacity reduction, etc. Benefit and cost analysis methods with the modeling are proposed to decide whether the introduction of V2G systems. Additionally, the methods will contribute to derive the future production and the unit cost of electric vehicle and battery and to get the technical and economic analysis.

• 한국건설관리학회논문집
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• 제14권3호
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• pp.115-122
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• 2013

표준품셈은 공공공사의 예정가격 산정을 위한 기초자료로 사용되어 왔다. 이는 매년 제 개정 업무가 수행되고 있으며 그로인해 많은 인원과 시간이 소요되고 있다. 이러한 문제점을 해결하기 위해 본 논문은 싸이클론을 활용한 방법론을 제시한다. 품셈산출을 위해 보조적 작업 및 비생산적 작업을 시뮬레이션 모형에 용이하게 반영할 수 있도록 품셈모듈을 개발하여 적용하는 방법론을 제시한다. 이에 본 연구는 알루미늄 폼 공정을 대상으로 싸이클론 시뮬레이션 및 워크샘플링 기법을 적용하여 품을 산출하고 그 결과를 비교하여 품셈모듈이 탑재된 싸이클론 모델이 품셈 제 개정 업무에서에 효율성 및 사용성이 있음을 검증한다.

• 디자인학연구
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• 제16권1호
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• pp.93-102
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• 2003

이 논문은 영농환경 개선을 위한 인삼재배사(일명 해가림 시설물) 디자인 표준화를 위한 연구이다. 연구배경의 핵심은 현 WTO 농산물 개방 체제하에서 한국의 세계적 농특산물인 고려인삼의 생산과 품질 가치를 더욱 확고히 하고 인삼 종주국으로서 위상에 걸맞는 현대식 인삼재배 시설을 최초로 도입하기 위한 기초연구를 제안함에 있다. 디자인 개념으로서는, 현재 목재 볏짚 비닐 등 일회성 또는 비표준화된 재료를 사용하므로서 매년 반복 재설치 작업 및 환경오염이 되고 있는 우리나라 인삼경작사의 노동 및 자원 낭비적 요소를 개선하고자 하였다. 구체적 개선 요소로서는 첫째, 양산체제에 의한 형태 및 구조의 표준화. 둘째, 반영구적 재료 표준화를 위한 수지 등 신소재 도입, 위 두 가지 내용을 한국적 이미지를 바탕으로 형상화 하고자 하였다. 디자인 결과로서, 인삼재배사의 기준 단위모델을 디자인하여 재배면적의 크기 형상에 따라 가변적으로 연결 조립하여 사용할 수 있도록 배려하였다.

• 한국환경과학회지
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• 제25권8호
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• pp.1155-1163
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• 2016

The treatment efficiencies of domestic sewage treatment processes were analysed and assessed to suggest and design a suitable technology for coal seam gas (CSG) water treatment. Two sewage treatment plants (S and G in Busan) were selected. The former operates with standard activated sludge and modified Ludzak Ettinger processes while the later uses the combination of $A_2/O$ and gravity fiber filtration. For both plants, the concentrations of BOD, $COD_{Mn}$, T-N and T-P were about 5.0, 19.0, 5.0, 11.0 and 1.0 ppm, respectively, which satisfy the discharge standards. Therefore, although sewage treatment processes seems to be applicable for CSG water treatment, additional processes to remove total dissolved solids and ionic compounds (i.e. bicarbonate) need to be introduced to produce fit-for-purpose water resources for beneficial use (in accordance with Water ACT 2013). This, for the CSG treatment process design, it is necessary to align the operating conditions with merging methods of combinable unit technology obtained from sewage treatment processes.

• 한국자동차공학회논문집
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• 제5권1호
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• pp.216-216
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• 1997

We developed the durability estimation and design systems to minimize the volume, considering the durability, efficiency, and design requirements of worm gears. That is, we consider each kind of factors affecting on durability on the basis of AGMA Standard for the cylindrical and double-enveloping worm gears. We also estimate input power on the basis of wear and durability, bending strength and deflection of worm shaft, and we developed the durability estimation and design systems of power transmission worm gears introducing the optimal design method on the personal computer to be easily used in field. Also, we developed a method which converts the design variables obtained from the optimal design method to integer values(number of worm threads, number of worm threads, number of worm wheel teeth, etc.,) to be used in real design and production. The developed durability estimation and design method can be easily applied to the design of worm gears used as power transmission devices in machineries and is expected to be used for weight minimization of worm gear unit.

• 대한안전경영과학회지
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• 제14권2호
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• pp.147-158
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• 2012

This paper aims to develop a new chain metrics for obtaining lean Overall Equipment Effectiveness(OEE) and present implementation strategy which considers the properties for Total Productive Maintenance(TPM) to reduce machine losses, Performance Analysis and Control(PAC) to reduce labor losses, Lean Production System(LPS) to reduce floor wastes, and Theory of Constraints(TOC) to minimize the problem of Capacity Constrained Resource(CCR). The study reviews the related literatures and reformulates the structure of machine losses, labor losses and field wastes. The research also develops the integrated productivity metrics according to time, units, reliability and maintainability. It is found that the study develops the actual productivity measure in terms of efficiency, effectiveness and standard productivity. In addition to that, it outlines and develops by using the integrated LPS and TPM, lean OEE measures such as Time Based Productivity(TBP), Unit Based Productivity(UBP), and Reliability & Maintainability Based Availability(RMBA). Implication examples are proposed to make it easier and available for practioners to understand the implementation strategies about TPM OEE, lean OEE and TOC OEE. Futhermore related to other studies, the research contributes to create a new chain productivity measures to clear the interrelationship concepts of productivity, efficiency and effectiveness. Moreover the paper develops the enhanced OEE measures by integration of TPM, PAC, LPS and TOC with the perspective of schedule, throughput, reliability, maintainability and availability.

• 수산해양기술연구
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• 제49권3호
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• pp.301-310
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• 2013

To suggest a standard concerning with the arrangement of bridge equipment, the authors conducted the video observations with 3CCD (charge coupled device) cameras installed on the ceil of the bridge for monitoring the working activities of two bridge teams (the skipper/mate1 and the skipper/mate2) in a Korean coastal large trawler(gross tonnage: 139) for five days from July 30th. 2010 and analyzed of the data. Work elements coded by the work activities were input on the sheet of work analysis by the time unit of 1 sec according to the time occurred. A single work element among the work activities for every 5 minutes was denoted as the number of occurrence. The frequency of equipment usage was limited only in the usage of the equipment. In the case of the navigation and the towing net two ranks were integrated and analyzed. On the other hand, in the case of the casting net and the hauling net, two processes were integrated to as one and then analyzed separately as two ranks. As the results, 15 elements of work was carried out between two bridge teams for the observation; lookout, radar, GPS plotter, fish finder, net monitor, fishing deck, RPM indicator, rudder angle indicator, compass card, for maneuver; steering, ship speed control, trawl winch operation and external communications, paper works and others. It was found that the work load of the skipper per 5 minutes accordance with the navigation, the casting net, the towing net and the hauling net are 20.5 times, 11.9 times, 38.0 times and 9.5 times respectively, the mates are 65.2 times, 66.5 times, 85.7 times and 59.1 times respectively. The radar was shown the highest frequency of the equipment usage and the next was the fish finder, the GPS plotter and the external communications in the case of the navigation. In the case of the towing net the frequency of usage was high the ranking as the radar, the net monitor, the fish finder, the GPS plotter, the steering system and the external communications. In the case of the integrated process both of the casting and hauling net the trawl winch was shown the highest frequency to the skipper and the next was the GPS plotter and the radar, and the steering system was shown the highest frequency to the mate and the next was the radar, the ship speed control system, the GPS plotter, the net monitor and the fish finder.

• 농촌계획
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• 제28권1호
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• pp.17-26
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• 2022

It is necessary to prepare a stable production base in advance for a change in the global grain market, and it is required to prepare comprehensive countermeasures such as securing technical skills and cultivation technology. Therefore, Korea, which relies on imports of major grains other than rice, could be exposed to a food crisis at any time unless the self-sufficiency rate of grains is improved. In order to respond to this new food crisis, it is necessary to find ways to efficiently utilize rice fields to increase the domestic grain self-sufficiency rate. From this point of view, interest and demand for the generalization of farmland that can be used as paddy fields and returned to paddy fields are increasing, and related research is also being continuously performed. In order to select a multipurpose farmland project site, this study extracted farmland containing 10% or more purchased and stockpiled farmland through spatial analysis (buffer, dissolve, intersect, etc.), and finally presented areas subject to multipurpose farmland projects. The target site for the multipurpose farmland project was finally selected by integrating data onto a point-by-point basis so that the current status of farmland purchased and stockpiled, Farm Manager Registration Records, and the Korean Soil Information System data (drainage classes, surface soil texture, field-suitability classification, etc.) can be used in combination. There are 175 areas where the multipurpose farmland is possible. Incheon 2, Gyeongbuk 40, Gangwon 2, Chungbuk 7, Chungnam 48, Jeonbuk 34, Jeonnam 19, Gyeongbuk 15, Gyeongnam 8. Chungcheongnam-do has the most target site for the multipurpose farmland project, and Gangwon-do is the least. It is expected to contribute to new commercialization and business expansion by deriving business areas by identifying the scale of the farmland multipurpose farmland project using Farm Manger Registration Records and spatial data.

• 디지털융복합연구
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• 제13권12호
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• pp.23-30
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• 2015

현제 지적업무는 대장(토지대장 및 임야대장)과 도면(지적도면 및 임야도면)의 전산화를 통해 디지털 지적관리체계로 전환되어 운영되고 있다. 지적측량 방식 역시 GPS측량, 전자평판 측량 등의 디지털 측량방식이 이용되고 있다. 지적측량에 따른 수수료는 현재 건설표준품셈과 국토교통부 자체 고시에 따른 기준을 기초로 산정하고 있다. 그러나 현재 고시되어 있는 지적측량수수료 산정 품셈은 종목에 따라 전산 환경을 반영하지 못하는 경우가 있다. 본 연구에서는 빠르게 변화하고 있는 디지털 지적관리 환경에서 개선을 필요로 하는 지적측량수수료 체계를 분석해 이에 대한 개선방안을 제시함으로써 디지털 환경에 적합한 지적측량수수료 체계 확립의 기반을 마련하고자 한다. 연구 성과로는 현황 분석을 토대로 디지털 환경에 적합한 용어의 변경 사용(부동산종합공부시스템), 새로운 품셈 종목에 관한 품셈체계 마련(지적기준점의 현황 조사 및 관리), 지적확정측량 품셈의 재조사 및 품셈 체계 마련을 제시하였다.