• Korean Chemical Engineering Research
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• 제56권6호
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• pp.878-883
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• 2018

A circulating fluidized bed (CFB) has been used in various chemical industries because of good heat and mass transfer. In addition, the methanol to olefins (MTO) process requiring the CFB reactor has attracted a great deal of interest due to steep increase of oil price. To design a CFB reactor for MTO pilot process, therefore, we has examined the hydrodynamic properties of spherical catalysts with different particle size and developed a correlation equation to predict catalyst holdup in a riser of CFB reactor. The hydrodynamics of micro-spherical catalysts with average particle size of 53, 90 and 140 mm was evaluated in a $0.025m-ID{\times}4m-high$ CFB riser. We also developed a model described by a decay coefficient to predict solid hold-up distribution in the riser. The decay coefficient developed in this study could be expressed as a function of Froude number and dimensionless velocity ratio. This model could predict well the experimental data obtained from this work.

• 산업경영시스템학회지
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• 제39권4호
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• pp.106-116
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• 2016

MTO (Make to Order) is a manufacturing process in which manufacturing starts only after a customer's order is received. Manufacturing after receiving customer's orders means to start a pull-type supply chain operation because manufacturing is performed when demand is confirmed, i.e. being pulled by demand (The opposite business model is to manufacture products for stock MTS (Make to Stock), which is push-type production). There are also BTO (Build to Order) and ATO (Assemble To Order) in which assembly starts according to demand. Lean manufacturing by MTO is very efficient system. Nevertheless, the process industry, generally, which has a high fixed cost burden due to large-scale investment is suitable for mass production of small pieces or 'mass customization' defined recently. The process industry produces large quantities at one time because of the lack of manufacturing flexibility due to long time for model change or job change, and high loss during line-down (shutdown). As a result, it has a lot of inventory and costs are increased. In order to reduce the cost due to the characteristics of the process industry, which has a high fixed cost per hour, it operates a stock production system in which it is made and sold regardless of the order of the customer. Therefore, in a business environment where the external environment changes greatly, the inventory is not sold and it becomes obsolete. As a result, the company's costs increase, profits fall, and it make more difficult to survive in the competition. Based on the customer's order, we have built a new method for order system to meet the characteristics of the process industry by producing it as a high-profitable model. The design elements are designed by deriving the functions to satisfy the Y by collecting the internal and external VOC (voice of customer), and the design elements are verified through the conversion function. And the Y is satisfied through the pilot test verified and supplemented. By operating this make to order system, we have reduced bad inventories, lowered costs, and improved lead time in terms of delivery competitiveness. Make to order system in the process industry is effective for the display glass industry, for example, B and C groups which are non-flagship models, have confirmed that the line is down when there is no order, and A group which is flagship model, have confirmed stock production when there is no order.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 추계학술대회 논문집
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• pp.231-231
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• 2015

무전해 Ni의 Metal turnover (MTO)가 증가함에 따라, Ni과 Sn-Ag-Cu솔더간 계면 금속간화합물층의 두꺼워지고, Ni-Sn-P층에 형성된 Nano void의 수가 많아지게 되어 취성파괴가 증가한다.

• 한국진공학회지
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• 제6권4호
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• pp.326-336
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• 1997

트랜지스터의 소오스/드레인 접합 특성에 가장 큰 영향을 미치는 인자는 이온 주입 시 발생한 실리콘 내에 발생한 결합이라는 사실에 착안하여, 기존 소오스/드레인 접합 형성 공정과 다른 새로운 방식을 도입하여 이온 주입에 의해 생긴 결함의 제어를 통해 고품질 초 저접합 $p^+$-n접합을 형성하였다. 기존의 $p^+$소오스/드레인 접합 형성 공정은 $^{49}BF_2^+$ 이온 주입 후 층간 절연막들인 TEOS(Tetra-Ethyl-Ortho-Silicate)막과 BPSG(Boro-Phospho-Silicate-Glass)막을 증착 후 BPSG막 평탄화를 위한 furnace annealing 공정으로 진행된다. 본 연구에서는 이러한 기존 공정과는 달리 층간 절연막 증착 전 저온 RTA첨가 방법, $^{49}BF_2^+$와 $^{11}B^+$ 을 혼합하여 이온 주입하는 방법, 그리고 이온 주입 후 잔류 산화막을 제거하고 MTO(Medium temperature CVD oxide)를 증착하는 방법을 제시하 였으며, 각각의 방법은 모두 이온 주입에 의한 실리콘 내 결합 농도를 줄여 기존의 방법보 다 더 우수한 양질의 초 저접합을 형성할 수 있었다.

• 산업공학
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• 제16권3호
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• pp.322-331
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• 2003

Most of existing studies for B2B are concerned with efficient search and/or negotiation. But nevertheless it is important to provide quick and transparent guarantee to the buyer, it is hard to find studies related with it. This article suggests the guarantee process for customer satisfaction after purchasing in B2B e-marketplace under make-to-order manufacturing environment. The process consists of three modules; a request and response, a feedback processing, and a work inquiry. Each of them is adopted according to the source of defect and business relationship of buyer, seller, provider, and repairer. All of the process is implemented in user-friendly fashion and a case is presented for the enterprise portal site.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.542-545
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• 2000

본 연구에서는 다품종 주문 생산 방식이 가지고 있는 여러 문제점들 중의 하나인 조립시스템에서의 소량 생산의 문제점을 해결하기 위해 효율적인 조립자동화 시스템을 통해 난점들을 해결하고자 한다. 본 연구의 내용은 첫째, 제품 및 구조의 분석으로 제거 및 통합 가능한 부품 파악을 하며 불필요하거나 생산 및 조립 용이성이 떨어지는 요소를 제거한다. 둘째, 취약 공정의 분석으로써 취약공정의 개선효과를 파악하고 근접 작업장과의 원활한 공정 흐름을 고려하여 취약공정 유무 파악 및 우선 개선 공정을 결정한다. 셋째는 조립시스템에 적합한 대안의 제시로써 자동화를 위한 적절한 메커니즘을 제시한다. 마지막으로 넷째, 제시된 대안의 평가를 통해 적합성 여부 판정한다. 즉, 미리 설정된 평가 기준에 의한 대안의 평가를 내리게 된다.

• 대한교통학회지
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• 제5권1호
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• pp.85-99
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• 1987

The transport a administration in Korea is meeting demands of developing international multimodal transport system. In the past, as Korea transport policy has been emphasizing on the passenger traffic, the physical distribution sector is far behind international trend. Regarding the urging necessities of reducting costs in transport in order to upgrade the competitive edge of industries, Korea has to develop the most efficient transport system so called international multimodal transport system. The existing transport system is inefficient because each transport mode is separate, so this system is aiming at reducing cost and time and developing freight transport. The scope and scheme of this thesis should be as following. Chapter 2. Systems Approach of International multimodal transport 1. general systems theory 2. definition of International multimodal transport system 3. MTO (multimodal transport operator) Chapter 3. Current Situation and Problems of this System. 1. international law and practice 2.current situation A. Europe B. U.S. C. Japan D. Korea Chapter 4. Policy Goal for Improving this System Chapter 5. conclusion.

• 대한안전경영과학회지
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• 제6권3호
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• pp.197-209
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• 2004

A company wishes to obtain a competitive edge by adopting an efficient logistics information system to control the logistics management process. The elements of the competitive edges a company targets are to maintain good quality, reduce cost and on-time delivery and those competitive edges are closely related to the cycle time of a product. The logistics information system in a company is also closely tied with other business activities than the logistics itself. Therefore it is essential to choose a system that will help rationalize the logistics but also overall business operations along the supply chain from manufacturing to distribution of the products. This paper aims to research and analyze a problem with a logistics information system through case study and to suggest a logistics information system with RFID in place adopted to eliminate problems such as damages, loss and defect rates.

• 한국표면공학회지
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• 제43권3호
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• pp.142-147
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• 2010

We evaluated characteristics of ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold) surface treatment for mobile equipment that requires high reliability, in addition to investigating surface treatment processes for semiconductor boards that require high reliability such as regular PCB-package systems, board-on-chip, chip-scaled package (CSP), etc and application for semiconductor package board of SIP, BOC. As a result, it appeared that ENEPIG has superior properties compared to ENIG surface treatment in corrosion resistance, solder junction, wetting, etc. We anticipate that these results will be able to lend credibility to ENEPIG as a low-cost alternative for producing mobile devices such as the cell phones, especially when applied to mass production.

• 한국응용곤충학회지
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• 제53권2호
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• pp.149-156
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• 2014

2009~2011년 동안 국내 주요 배추 재배지 5개 지역(평창, 홍천, 봉화, 무주, 제주)에서 살충제에 대한 복숭아혹진딧물의 저항성 발달 정도를 조사하고, 야외 개체군에 적용 가능한 살충제 저항성 마커를 개발하기 위해 본 연구를 수행하였다. 조사된 5개 지역 개체군 모두 여러 살충제 종류에 대하여 다양한 저항성을 보였다. 다양한 저항성을 보인 5개 지역 야외 개체군으로부터 여라 살충제에 대하여 복합적으로 저항성을 보이는 복합저항성 계통(MR)을 선발하였고, 이 MR과 모든 지역 채집 개체군에 대해 등전점전기영동과 정량염기서열분석(quantitative sequencing, QS)을 통하여 에스터레이즈 과발현과 살충제 작용점 내 돌연변이를 확인하였다. MR을 포함한 모든 야외 개체군에서 에스터레이즈의 과발현과 아세틸콜린에스터레이즈 1 유전자(ace1)의 StoF 돌연변이를 확인할 수 있었다. 넉다운 저항성 돌연변이로 잘 알려진 파라 타입 나트륨 채널 유전자(para)의 LtoF 돌연변이는 모든 지역 채집 개체군은 물론 비펜스린에 대해 3,461배 저항성을 보이는 MR에서도 발견되지 않았다. 그 외에 MtoL 돌연변이를 발견하였는데, 생물검정 결과 저항성 수준과 돌연변이 발생 빈도가 일치하였다. 따라서 생물검정 대신, 이러한 분자 마커를 활용 한다면 더 효율적으로 살충제 저항성 평가가 가능할 것이다. 이러한 분자 마커들(ace1의 StoF, para의 MtoL)은 정량염기서열분석, PCR amplification of specific alleles (PASA) 등의 진단 방법에 쉽게 응용이 가능 하고, 이러한 방법은 야외 복숭아혹진딧물 저항성 관리에 적용이 가능 할 것이다.