• Environmental and Resource Economics Review
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• v.17 no.3
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• pp.135-166
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• 2008

This paper reports the empirical results of comparing the willingness to pay(WTP) for health risk reductions and the willingness to accept(WTA) for risk increases using experimental market methods in the first time in Korea. Health risks were defined as probabilities of premature death from exposure to one of As, Pb, and THM in tap water. A total of six experimental markets with 15 participants in each experiments were held using 20 repetitive Vickrey second-price sealed-bid auctions. To compare the effects of market experiences, trading a marketed good, candy bar, was introduced before the trading the non-marketed good, drinking water risks. Moreover, an objective risk information was provided after the first 10 trials to incorporate learning processes. Regardless of marketed or non-marketed goods, the mean of WTA exceeded the mean of WTP at the first auction trial. As experimental trials proceeded, the disparity between WTA and WTP for marketed goods disappeared. However results for non-marketed goods were rather mixed to the extent that WTA for health risks from As (relatively high risk leves) were significantly larger than WTP, while there were no significant difference between WTA and WTP for health risks fro Pb and THM (relatively low risk levels). On the other hand, participants seemed to respond in a 'rational' manner to the objective risk information provided, with positive learning effects of market-like experience(especially in the WTA experiments).

• Proceedings of the Safety Management and Science Conference
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• 2010.11a
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• pp.639-649
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• 2010

신뢰성 기술은 제품이 고장 없이 일정기간 사용할 수 있게 하는 기술로 시장점유율과 고객만족을 높이는 효과적이고 전략적인 필수 요소이다. 검사시점의 적합성에 대한 평가가 아닌 제품 및 시스템의 설계에서부터 폐기까지의 제품수명주기에 대한 신뢰성 평가를 다루는 제품의 신뢰성인증과 신뢰성경영시스템 인증 확보가 시급한 과제이다. 이를 위한 제품 수명의 평균과 분산을 효과적으로 관리할 수 있는 신뢰성 식스시그마 기술개발과 확보가 중요 현안과제이다. 정규분포를 가정한 대부분의 품질경영시스템에서의 식스시그마 접근법은 비정규 분포를 따르는 신뢰성특성과 실험계획기법 등을 고려해야 하는 신뢰성 식스시그마에서의 적용의 한계가 많다. 본 연구에서는 품질혁신 방법론인 식스시그마 기법을 토대로 신뢰성경영시스템에서 맞는 식스시그마 구축의 방향성을 제시하고자 한다.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.55-79
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• 2013

In this paper, we propose a hybrid genetic algorithm (HGA) approach to effectively solve the reverse logistics network with centralized centers (RLNCC). For the proposed HGA approach, genetic algorithm (GA) is used as a main algorithm. For implementing GA, a new bit-string representation scheme using 0 and 1 values is suggested, which can easily make initial population of GA. As genetic operators, the elitist strategy in enlarged sampling space developed by Gen and Chang (1997), a new two-point crossover operator, and a new random mutation operator are used for selection, crossover and mutation, respectively. For hybrid concept of GA, an iterative hill climbing method (IHCM) developed by Michalewicz (1994) is inserted into HGA search loop. The IHCM is one of local search techniques and precisely explores the space converged by GA search. The RLNCC is composed of collection centers, remanufacturing centers, redistribution centers, and secondary markets in reverse logistics networks. Of the centers and secondary markets, only one collection center, remanufacturing center, redistribution center, and secondary market should be opened in reverse logistics networks. Some assumptions are considered for effectively implementing the RLNCC The RLNCC is represented by a mixed integer programming (MIP) model using indexes, parameters and decision variables. The objective function of the MIP model is to minimize the total cost which is consisted of transportation cost, fixed cost, and handling cost. The transportation cost is obtained by transporting the returned products between each centers and secondary markets. The fixed cost is calculated by opening or closing decision at each center and secondary markets. That is, if there are three collection centers (the opening costs of collection center 1 2, and 3 are 10.5, 12.1, 8.9, respectively), and the collection center 1 is opened and the remainders are all closed, then the fixed cost is 10.5. The handling cost means the cost of treating the products returned from customers at each center and secondary markets which are opened at each RLNCC stage. The RLNCC is solved by the proposed HGA approach. In numerical experiment, the proposed HGA and a conventional competing approach is compared with each other using various measures of performance. For the conventional competing approach, the GA approach by Yun (2013) is used. The GA approach has not any local search technique such as the IHCM proposed the HGA approach. As measures of performance, CPU time, optimal solution, and optimal setting are used. Two types of the RLNCC with different numbers of customers, collection centers, remanufacturing centers, redistribution centers and secondary markets are presented for comparing the performances of the HGA and GA approaches. The MIP models using the two types of the RLNCC are programmed by Visual Basic Version 6.0, and the computer implementing environment is the IBM compatible PC with 3.06Ghz CPU speed and 1GB RAM on Windows XP. The parameters used in the HGA and GA approaches are that the total number of generations is 10,000, population size 20, crossover rate 0.5, mutation rate 0.1, and the search range for the IHCM is 2.0. Total 20 iterations are made for eliminating the randomness of the searches of the HGA and GA approaches. With performance comparisons, network representations by opening/closing decision, and convergence processes using two types of the RLNCCs, the experimental result shows that the HGA has significantly better performance in terms of the optimal solution than the GA, though the GA is slightly quicker than the HGA in terms of the CPU time. Finally, it has been proved that the proposed HGA approach is more efficient than conventional GA approach in two types of the RLNCC since the former has a GA search process as well as a local search process for additional search scheme, while the latter has a GA search process alone. For a future study, much more large-sized RLNCCs will be tested for robustness of our approach.

• Food Science and Industry
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• v.52 no.1
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• pp.52-59
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• 2019

The present article covers a brief introduction on how repeated exposure design can be utilized for developing new food products. A generic consumer taste test which measures consumer acceptance in one trial may have limitation in predicting long-term acceptability of a product. The article describes the changes in food preference and choice during the course of life from infants to elderly. Then, several possible theories that proposes to delineate the underlying mechanisms for acquiring the liking for food is introduced. The article also discusses general experimental design, case studies which adopted repeated exposure design, the limitations and rapid test methods to predict long-term acceptance.

• Prospectives of Industrial Chemistry
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• v.23 no.1
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• pp.42-54
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• 2020

계속적인 충·방전이 가능하여 반영구적으로 사용이 가능한 2차 전지는 친환경 소재로 주목받고 있으며, 노트북 컴퓨터와 휴대전화, 캠코더 등 소형 전자기기뿐만 아니라 전기자동차의 핵심소재이다. 전기자동차 시장의 성장과 더불어 중대형 에너지 저장용 2차 전지 시장의 규모는 더욱 확대되고 있어 관련된 소재의 개발 경쟁과 관심이 날이 갈수록 뜨거워지고 있다. 따라서 소재개발 측면에서 2차 전지 핵심 소재의 물성 발현의 원리 등을 이해하고 최적 소재 설계를 위해서는 원자 레벨에서의 소재 설계 접근법이 필요하다. 따라서 실험적인 연구가 어려운 부분과 원자단위에서의 물질 현상에 대한 이해 그리고 연구 개발의 효율성 증진을 위해서 전산재료과학(computational materials science) 기술이 광범위하게 활용될 수 있다. 본 기고문에서는 리튬이온전지에서의 전극 소재에 대한 전산재료모사의 활용과 연구동향에 대하여 소개하고자 한다.

• Environmental and Resource Economics Review
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• v.9 no.4
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• pp.747-771
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• 2000

This paper reports the results of a study to elicit willingness to pay (WTP) for changes in health risks from exposure to As, Pb, THM in tap water using experimental market method. The experimental market method, compared with other non-market valuation methods, allows us to use incentive compatible demand revealing scheme, to acquire market-like experience through repetitive auctions, and to incorporate learning process by providing new information during the session. Participants seemed to utilize the objective risk information in a 'rational' manner, and to change their WTP bids accordingly. Moreover they were able to reduce the 'ambiguity' in risk perception processes when objective risk probabilities provided are quite different from their subjective perceptions. Nonetheless, anchoring effects appeared to be still persistent in spite of market-like experience and learning opportunity. And implicit values entailed by WTP bid/risk tradeoffs indicate a wide variation in values across alternative risk reductions and overrated responses to very small risk reductions.

• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.46-48
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• 2008

나노복합 블레이드가 반도체 웨이퍼 가공을 위한 마이크로급 나노장치나 그 이상의 나노급 구조체를 위해 사용되었다. 금속 블레이드는 실리콘 웨이퍼 가공을 위해 사용되어 왔다. 그러나, 최근 레진 복합 블레이드는 반도체나 핸드폰의 쿼츠 웨이퍼 가공에 사용된다. 유기 또는 비유기 재료 선정은 기계가공성, 전기 전도성, 강도, 연성 및 웨이퍼 저항을 가진 블레이드를 만드는데 중요하다. 고성능 응용의 증대 요구에 따라 개발된 고기술 비유기성 재료의 혼합은 낮은 가격에 고기능의 신뢰도를 필요로 한다. 나노 입자의 크기를 가진 레진 복합물의 마이크로 설계는 입자간 상호작용의 제어가 필요하다. 형상 제작 동안 마이크로 차원에 두께를 유지하기 위해서는 마이크로/나노급 제작을 위한 가공기술이 중요한 것 중의 하나이다. 본 연구에서는 핫 프레스 구조물이 원래 설계 기준과 두께 차이의 실험 접근법을 사용해 만들어졌다. 다른 습식 공정 기술은 차원의 허용치를 개선하기 위해 만들었다. 실험들과 해석들은 신뢰성 결과가 사용가능함을 보여주었다. 반도체 시장에 사용될 레진 복합 블레이드의 개선 효과가 논의되었다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.231-234
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• 2005

본 실험은 돈육 후지 부위를 이용하여 육포 제조시 텀블링 시간에 따른 육포의, 이화학적 및 관능적 특성을 조사하여 표준화된 육포제조의 기초 자료를 제공하고자 실시하였다. 텀블링 시간에 따른 건조전 육포 양념육의 제품수율은 30분까지는 수율이 유의적으로 증가하는 경향을 보였으나, 60분 동안 텀블링을 실시하였을 때는 30분보다 낮은 값을 나타내었다. 텀블링 시간에 따라 pH는 차이가 없었으나, 보수력은 텀블링 30분까지 유의적으로 증가하였고 이후 부터는 차이가 없었다. 육색은 텀블링 시간이 경과함에 따라 $L^{\ast}-$값과 $b^{\ast}-$값은 감소하는 경향을 보였으나 반대로 $a^{\ast}-$값은 텀블링 시간이 증가함에 따라 점점 증가하는 경향을 보였다. 건조후 제조된 돈육육포의 수분함량은 $29{\sim}30%$ 정도를 유지하였으며, 건조수율은 모두 $48{\sim}49%$ 정도의 높은 수율을 보였다. 육포의 $L^{\ast}-$값은 30분 및 60분 동안 텀블링을 실시하였을 때 10분 동안 텀블링을 실시한 육포보다 낮게 나타났다. 60분 동안 텀블링한 육포의 $a^{\ast}-$값은 10분간 텀블링한 것보다 높았으며, $b^{\ast}-$값은 $a^{\ast}-$값과는 반대의 경향을 나타내었다. 탄력성(springiness)은 60분 동안 텀블링한 육포가 10분 동안 텀블링한 육포보다 높은 값을 보였으나, 탄력성을 제외한 모든 항목에서 유의차가 나타나지 않았다. 관능검사는 모든 항목에서 30분 이상 텀블링한 육포가 좋은 평가를 받았으나, 처리구간에 유의차는 나타나지 않았다.pm을 spiking한 후 SPE상에서 SCX(Strong cation exchange column)을 통한 clean-up과정을 거친 후의 STP의 limit of quantification(LOQ)는 약 0.44ppm이었으며, 이에 대한 회수율은 89.7${\pm}$2.3%(n=6)를 나타냈다. 실제 CODEX에서 권장한 우유의 MRL이 0.6ppm인 점을 감안하면 CODEX권고치에 도달할 수 있는 것으로 판단되었다. 따라서 본 연구에서 개발 된 시험법은 지금까지 국내적으로 STP에 대한 시험법이 확립되어 있지 않은 것으로 이와 아울러 간편한 parallux와 병용해 STP에 대한 정량 및 정성 분석을 유도체화 장치 및 형광검출기를 이용해 잔류항생물질 STP에 대한 분석시험법을 개발하였다.화와 네트워크 조직망 구축을 위한 지역중심의 복합 생활문화 공간이 필요할 것이며, 이를 촉진키 위한 mentor academy시스템 접근을 통해 점점 고령화되어 가고 있는 재래시장에 대해 차별적 특성이 반영된 종합적이고 체계적 접근 방법연구가 필요하다./TEX> 자체기술개발, 선진기술 도입, 산업간 및 산업내 기술확산, 국제기술협력 ${\rightarrow}$ 기술혁신의 촉진 ${\rightarrow}$ 총요소생산성과 기업경쟁력(자원 및 역량, 프로세스 경쟁력, 품질경쟁력, 시장경쟁력, 고객성과, 시장성과, 재무성과)의 제고 ${\rightarrow}$ 가격경쟁력(임금, 금리, 물류비용, 환율 등)과 비(非)가격경쟁력(디자인, 에프터서비스, 품질, 운송 등)의 제고 ${\rightarrow}$ 국가경쟁력의 제고 ${\rightarrow}$ 국제수지 흑자 ${\ri

• Journal of the Microelectronics and Packaging Society
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• v.30 no.4
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• pp.69-78
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• 2023

With the rapid growth of artificial intelligence, the demand for semiconductors is enormously increasing everywhere. To ensure the manufacturing quality and quantity simultaneously, the importance of automatic defect detection during the packaging process has been re-visited by adapting various deep learning-based methodologies into automatic packaging defect inspection. Deep learning (DL) models require a large amount of data for training, but due to the nature of the semiconductor industry where security is important, sharing and labeling of relevant data is challenging, making it difficult for model training. In this study, we propose a new framework for securing sufficient data for DL models with fewer computing resources through a divide-and-conquer approach. The proposed method divides high-resolution images into pre-defined sub-regions and assigns conditional labels to each region, then trains individual sub-regions and boundaries with boundary loss inducing the globally coherent and seamless images. Afterwards, full-size image is reconstructed by combining divided sub-regions. The experimental results show that the images obtained through this research have high efficiency, consistency, quality, and generality.

• Journal of Intelligence and Information Systems
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• v.13 no.4
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• pp.17-34
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• 2007

Organizations have realized the importance of CRM. To obtain the maximum possible lifetime value from a customer base, it is critical that customer data is analyzed to understand patterns of customer response. As customer databases assume gigantic proportions due to Internet and e-commerce activity, data-mining-based market segmentation becomes crucial for understanding customers. Here we raise a question and some issues of using single SOM approach for clustering while proposing multiple self-organizing maps approach. This methodology exploits additional themes on the attributes that characterize customers in a typical CRM system. Since this additional theme is usually ignored by traditional market segmentation techniques we here suggest careful application of SOM for market segmentation.