• Industrial Engineering and Management Systems
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• 제12권4호
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• pp.330-335
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• 2013

A surface mount device (SMD) assembles electronic components on printed circuit boards (PCB). Since a component assembly process is a bottleneck process in a PCB assembly line, making an efficient SMD plan is critical in increasing the PCB assembly line productivity. Feeder assignment is an important part of the SMD plan optimization. In this paper, we propose a feeder re-assign improvement algorithm for a specific type of SMD machine with a piano type multi-head gantry. Computational results on some real-world benchmark data sets show the effectiveness of our proposed algorithm.

• 한국정보처리학회논문지
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• 제4권1호
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• pp.97-106
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• 1997

소프트웨어 재 사용 기법은 기존의 시스템을 개발하는데 사용된 다양한 형태의 정보와 지식을 다른 시스템 개발에 재적용함으로써 생산성을 향상할 수 있고 유지보 수를 쉽게 할 수 있다. 본 논문에서는 C 및 C++로 개발된 원시 코드를 대상으로 역공 학을 이용하여 재사용 가능한 부품을 수출하고 이 부품을 저장 및 검색, 합성하여 사 용할 수 있는 재사용 시스템 CSORUS(C and C++ SOurce ReUse System)를 설계 및 구현 하였다. 역공학을 이용하여 재사용 부품을 구축할 경우 실무 분야에서 적용되어 검증 받은 신뢰도가 높은 부품이므로 재사용 부품의 신뢰도와 새로운 시스템의 유지보수를 쉽게 할 수 있다면 장점이 있다.

• Journal of Ginseng Research
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• 제27권4호
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• pp.178-182
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• 2003

Vesicular-arbuscular mycorrhizae (VAM) fungi naturally colonise American ginseng roots and this relationship is highly beneficial to enhance plant productivity. Our goal was to determine the effect of adding two Glomus species (Glomus etuticatum, G. intraradices) on survival, photosynthetic capacity, growth, morphology and root ginsenoside content of one-year-old American ginseng plants grown in a broadleaf forest. While our study revealed that VAM inoculations significantly affected root morphology and Re ginsenoside content, the survival, photosynthetic capacity and root growth of American ginseng plants were not significantly influenced by VAM inoculations. Surface area and volume of rootlets were 16-25% higher for ginseng grown in VAM-inoculated soil compared to those grown in the control plots. Also, Re ginsenoside content was 18 ％ higher in YAM-inoculated roots compared to controls.

• 드라이브 ㆍ 컨트롤
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• 제19권1호
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• pp.1-7
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• 2022

Recently, a re-painting robot was developed to semi-automatically conduct blasting work in bridge spaces to improve work productivity and worker safety. In this study, a vision sensor-based monitoring module was developed to automatically move the re-painting robot along the path. The monitoring module provides direction information to the robot by analyzing the boundary between the painting surface and the metal surface. To stably measure images in unstable environments, various techniques for improving image visibility were applied in this study. Then, the driving performance was verified in a similar environment.

• KIEAE Journal
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• 제13권1호
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• pp.151-157
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• 2013

Since high-rise building construction sites are usually located in crowded city areas, sufficient spaces for the inventories of key materials are rarely available. This spatial constraints have been one of the critical challenge that may cause productivity loss and increasing costs of the high-rise building construction projects. The proper material inventory management is certaing a key to the success of high-rise building construction projects as it handles difficulty of securing material stock yards, changes in demands, uncertain delivery time through integrating the construction schedules and actively responding to the key materials attributes. In this light, this research analyzes the latest inventory model, (Q,r) model, in accordance with the high rise building characteristics. This research suggests an optimal inventory management of re-bar considering various demands and lead times. The case study is also presented with regard to the re-bar inventory management.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 1999년도 학술대회지 vol.2
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• pp.431-445
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• 1999

This paper introduces a development of component based framework of supply-chain management. The existing legacy system, which is not designed for object-oriented paradigm, is re-modeled using unified modeling language. Components are extracted from the legacy application, and frameworks are also designed in order to increase productivities of software development. Design issues concerning component and framework development are discussed with real situation. Performance and development productivity issue are also discussed with discussing component size and scope. A real case is presented in connection with the discussed issues.

• KSBB Journal
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• 제4권3호
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• pp.281-287
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• 1989

The experimental study reported herein was to investigate to separation characteristics of a tangential flow membrane in a continuous recycle situation. Physical and dynamic analyses are performed on the membrane system in order to relate relevant variables to the capacity of separation. The results of separation process may be summarized by a proposed equation:Sh=A(Re.Sc.dh/L)1/3. It was shown also by the analyses that effective separation of sugar and cell was attainable by means of tangential membranes, thereby enhancing ethanol productivity in fermentation with continuous cell and substrate recycle.

• 한국농림기상학회지
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• 제11권1호
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• pp.19-26
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• 2009

연속적인 지표 플럭스 관측으로부터 축적되는 엄청난 양의 자료를 체계적으로 처리분석하고 종합하여 일관성 있는 결과를 도출해 내려면 에디 공분산 자료 처리 방법의 표준화가 우선되어야 한다. 이 논문에서는 국내 타워 플럭스 관측 네트워크인 KoFlux의 표준화된 자료 처리 방법을 소개하고, 처리 방법이 다른 경우에 생길 수 있는 지표 플럭스의 불확실성을 평가하였다. 광릉 활엽수림에서 관측된 탄소 플럭스의 경우, 순생태계교환량(net ecosystem exchange, NEE)과 생태계호흡량(ecosystem respiration, Re)은 각각 자료 처리 방법의 차이에 따라 민감한 반응을 보였다. 그러나 두 양이 서로 상쇄되어, 총일차생산량(gross primary productivity, GPP=NEE+Re)은 자료 처리 방법이 다른 경우에도 불구하고 오차 범위 내에서 일치하였다. 이러한 결과는 GPP를 산출할 때에 Re를 독립적으로 관측하는 것이 중요함을 시사한다. 반면 수증기 플럭스(증발산)의 경우, 야간 토양 증발이 작아서 연 적산증발산량은 자료 처리 방법에 민감하지 않았다. 이렇게 표준화된 자료처리 프로토콜을 아시아 타워 플럭스 네트워크인 AsiaFlux에 적용할 경우, 지역 규모 탄소 순환, 역학 식생 및 지면과정 모형의 검증을 위한 일관성 있는 데이터베이스의 구축이 가능해 질 것이다.

• 산업경영시스템학회지
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• 제39권1호
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• pp.153-161
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• 2016

Semiconductor manufacturing has suffered from the complex process behavior of the technology oriented control in the production line. While the technological processes are in charge of the quality and the yield of the product, the operational management is also critical for the productivity of the manufacturing line. The fabrication line in the semiconductor manufacturing is considered as the most complex part because of various kinds of the equipment, re-entrant process routing and various product devices. The efficiency and the productivity of the fabrication line may give a significant impact on the subsequent processes such as the probe line, the assembly line and final test line. In the management of the re-entrant process such as semiconductor fabrication, it is important to keep balanced fabrication line. The Performance measures in the fabrication line are throughput, cycle time, inventory, shortage, etc. In the fabrication, throughput and cycle time are the conflicting performance measures. It is very difficult to achieve two conflicting goal simultaneously in the manufacturing line. The capacity of equipment is important factor in the production planning and scheduling. The production planning consideration of capacity can make the scheduling more realistic. In this paper, an input and scheduling rule are to achieve the balanced operation in semiconductor fabrication line through equipment capacity and workload are proposed and evaluated. New backward projection and scheduling rule consideration of facility capacity are suggested. Scheduling wafers on the appropriate facilities are controlled by available capacity, which are determined by the workload in terms of the meet the production target.

• 한국미생물·생명공학회지
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• 제47권3호
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• pp.381-389
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• 2019

Chlorella vulgaris was isolated from the Nile River, Qalubia Governorate, Egypt, for possible use in biodiesel production. BG-II nutrient growth media was used for isolation and laboratory growth. Identification was performed via 18S rRNA gene amplification, followed by sequencing. The alga was exposed to UV-C (254 nm) for 15, 30, and 45 s to improve dry weight accumulation and to increase the oil production. Daily measurements of dry weight ($g{\cdot}l^{-1}$) were performed; oil content and volumetric lipid productivity were also determined. UV-C exposure led to an increase in the volumetric lipid productivity by 27, 27.3, and $32.4mg{\cdot}l^{-1}{\cdot}d^{-1}$ with 15, 30, and 45 s, respectively, as compared with the control, which resulted in $18mg{\cdot}l^{-1}{\cdot}d^{-1}$. Of the examined mutants, the one with the highest productivity was re-irradiated by UV-C (254 nm) for 15, 30, 45, and 60 s. For 15 s of exposure time, the oil content increased to 34%, while it was 31% at 30 s; further, it decreased to 22% at 45 and 60 s exposures. The fatty acid methyl ester profile was 82.22% in the first mutant at 45 s, compared with the wild strain that contained a total of 66.01% of FAs. Furthermore, the highest levels of polyunsaturated fatty acid methyl ester were observed in the mutant exposed for 45 s, and it reached 11.41%, which reduced the cetane number to 71.3.