• 전기화학회지
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• 제9권4호
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• pp.170-177
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• 2006

고분자 전해질 연료전지의 분리판의 유동채널 설계는 고전류밀도에서 발생하는 농도분극에 직접적인 영향을 줄 뿐 아니라 생성되는 물의 효과적인 전달을 위하여 매우 중요하다. 평행류 유로와 interdigitated 유로의 성능비교를 위하여 연료극과 공기극이 포함된 완전한 형태의 고분자 전해질 연료전지의 3차원 수치해석모델을 개발하였다. 수치해석모델을 사용하여 평행류 유동장과 interdigitated 유동장의 압력강하, 채널간의 물질전달, $H_2O$와 $O_2$의 농도 분포 그리고 i-V 성능을 비교하였다. 그 결과 물질전달에서 채널간의 대류에 의한 물질전할이 더욱 우수한 interdigitated 유동채널에서 성능이 더 높게 나타났으며 압력강하는 보다 크게 나타나 설계시 두가지 성능에 대한 상호보완이 필요함을 알 수 있었다.

• 한국임상수의학회지
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• 제29권1호
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• pp.58-62
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• 2012

To protect aquatic animal health of importing countries from the potential risks associated with exotic diseases introduced through international trade of live aquatic animals, inspection of designated commodities at ports of entry is a critical component of the safeguarding system. The only way to be 100% confident that no fishes in a shipment are infected with a specific agent is to test every fish in the commodity imported with a perfect diagnostic test. For the majority of cases, this is unrealistic since the group of interest may very large particularly for aquatic animals, or imperfect tests are often available. It is, therefore, more common to test a fixed proportion of a group by preplanned sampling schemes. However, decision making based on results of testing the sample can provide quite a chance that infected groups may be misclassified as uninfected, depending on sampling strategy employed. The objective of this study was to determine the possibility that one or more fishes in the group imported being infected but tests negative after inspecting samples. This question is critical to government authorities to examine whether sampling plan is sufficient to achieve the purpose intended for. At fixed population size, the maximum number of infected fishes when all tests negative was decreased as the sampling fraction increased. The probability of including at least one undetected but infected fish in a group for negative tests increased with the number of fish tested or true prevalence. The risk was much lesser where high sensitivity test was assumed; when increasing test sensitivity from 0.9 to 0.99, this risk was dramatically reduced to about a tenth or a fourth for prevalence ranges from 2 to 10%, given sample size ranges from 10 to 200. Based on the preliminary analysis, the author concluded that current sampling plan testing 4-8% of the import proposal for human consumption still can yield high false negative results. Therefore, from the quarantine inspection point of view, an enforced commodity-specific sampling design that accounts for the cost of testing with an imperfect test at the specified design prevalence is urgent.

• 한국항만경제학회지
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• 제31권3호
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• pp.107-120
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• 2015

기업들의 국제물류체계는 물류비용과 시간의 절감뿐만 아니라 물류의 부가가치 창출 기능을 극대화하기 위해 급속히 발전할 전망이다. 글로벌 공급체인 운영방식인 Ro-Ro 운송은 운송시간의 정확성, 비용절감, 신속성, 안전성 향상 등에서 경쟁력이 높아 이를 활용하기 위한 전략이 급증할 것으로 전망된다. 이에 본 연구에서는 한일간 교류 물동량 분석을 통해 Ro-Ro 부두 조성의 적정 수요와 규모를 추정해 보고자 하였다. 이를 위해 한일간 Ro-Ro선의 운항속도에 근거한 운항거리를 바탕으로 1권역과 2권역으로 구분하여 부산항과의 물동량(컨테이너와 일반화물)을 분석하였다. 분석된 물동량을 바탕으로 Ro-Ro선 이용 가능성이 높은 품목의 비중을 추정한 후 한일간 Ro-Ro 부두의 이용가능 물동량을 추정하였다. 추정된 물동량을 처리하기 위해서는 2만톤급 2개 선석과 장치장 10만$m^2$ 정도가 필요한 것으로 판단된다. 부산항에 Ro-Ro 전용 부두 조성을 통해 컨테이너 일변도의 항만정책을 탈피하고, 글로벌 기업들의 수요에도 대응할 수 있을 것이다.

• 산업경영시스템학회지
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• 제40권3호
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• pp.116-122
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• 2017

Advances in information technology, communication and network technology are radically facilitating digital convergences as the integration of human, equipment, and space in the current industry 4.0 era. In industry 4.0 environment, the vast amount of information with networked computing technology can be simultaneously accessible even in limited physical space. Two main benefit points out of these information are the convenience and efficiency in their online transactions either buying things online or selling online. Even though there exist so many benefits that information technology can create for the people doing business over the internet there is a critical problem to be answered. In spite of many such advantages, however, online transactions have many dysfunctions such as personal information leakage, account hacking, and cybercrime. Without preparing the appropriate protection methods or schema people reluctantly use the transaction or would find some other partners with enhanced information security environment. In this paper we suggested a novel selection criteria that can be used to evaluate the reliable means of authentication against the expected risks under on-going IoT based environment. Our selection criteria consists of 4 steps. The first step is services and risk identification step. The second step is evaluation of risk occurrence step. The third step includes the evaluation of the extent of damage. And the final step is the assessment of the level of risk. With the help of the above 4 step-approach people can systematically identify potential risks hiding in the online transactions and effectively avoid by taking appropriate counter actions.

• 한국항해학회지
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• 제18권2호
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• pp.91-109
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• 1994

Technological and organisational changes in transport system have introduced new dimension into port system development and inter-port competition. The quality of service now required by the customer is costly and not easily provided by small shipping companies and small ports. It has been suggested that in the future container shipping may be concentrated by space-sharing arrangements or actual mergers into the hands of a few mega-operators with the investment potential to provide total logistics networks. In order to compete effectively, high load factors will be essential and port concentration inevitable. A fa-voured few ports will become the load centres and other ports will assume a secondary feeder role. In this study, three questions are raised and attempts are made to answer them : (a) what is the new role of ports today ; (b) why should ports be engaged in this new role ; and (c) how can ports play this new role. In short, a modern port should be a service centre and a logistic platform for international trade and transport-a third generation port. Ports, in particular, have to make every effort to be competitive in the cost and quality of services and to make the port a transport and distribution service centre. For most ports, this is not an option but a must ; an essential requirement for survival in this win or lose situation. The best way to win is to maintain a close contact with port users, listen to them, discuss with them, help them and satisfy them. That is port marketing. Starting from the findings of port marketing, it is es-sential to work out appropriate development plans and marketing targets and to improve port competitive-ness. As an alternative method, a port competitiveness model is suggested, which may help port managers to make appropriate improvements.

• 정보학연구
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• 제7권3호
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• pp.63-81
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• 2004

전자상거래가 활성화되어가고 있는 상황하에서 우리나라는 물류의 아웃소싱에 대한 관심이 높아지고 있음에도 불구하고 국내 물류서비스를 담당하고 있는 제3자 물류업체는 규모가 영세하고 전문화된 활동영역이 미미하고, 화주기업의 경우에도 기업 내부정보의 유출과 통제력 약화 등을 우려하여 상호간 유기적 연계가 이루어지고 있지 않은 실정이다. 이에 따라 제3자 물류가 정착되기 위해서는 정부측면에서 불필요한 행정규제를 철폐하고 물류산업 활성활ㄹ 위한 특별법의 제정이 필요하고, 기업측면에서는 효율적인 물류전략 추진, 물류서비스 기반요소 확충, 물류업체 컨설팅 능력 확보, 정보기술에의 투자 등의 다각적인 전략이 요청된다.

• 통상정보연구
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• 제16권2호
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• pp.3-22
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• 2014

아세안은 아세안 경제공동체를 통해 거대경제권과 아시아의 FTA 허브로 변화하고 있다. 한국이 아세안과 통상관계를 확대 발전시키려면 아세안의 변화를 정확히 이해해야 한다. 한국의 대아세안 통상정책, ODA 정책, 기업의 투자는 아세안의 변화와 변화하고자 하는 미래 모습에 발맞추어 시의적절하게 이루어져야 한다. 한국은 아세안의 변화를 체계적으로 이해하고 이를 통해서 한국이 아세안과 통상협력을 통해 동반성장할 수 있는 방안을 마련해야 한다. 특히 한국은 아세안의 통상파트너로서 아세안의 한계와 문제점을 한아세안 통상협력을 통해 해결할 수 있는 다각적인 방안을 마련해야 한다. 본 논문은 아세안의 변화와 한아세안 통상관계를 다각적으로 분석하여 아세안의 변화에 능동적으로 대응할 수 있는 한국의 대아세안 통상전략을 제시하고자 한다.

• 한국토양비료학회지
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• 제47권3호
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• pp.141-146
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• 2014

The necessity to develop economical and eco-friendly technologies is steadily increasing. Plant growth promoting rhizomicrobial strains PGPR are a group of microorganisms that actively colonize plant roots and increase plant growth and yield. Pot experiments were used to investigate the potential of some rhizobacterial strains to enhance the Brassica rapa growth. Microbial strains were successfully isolated from the rhizosphere of Panax ginseng and characterized based on its morphological and plant growth promotion characters. Surface disinfected seeds of Wisconsin Fast B. rapa were inoculated with the selected PGPR microorganisms. The different pots treatments were inoculated by its corresponding PGPR ($10^7cfu\;mL^{-1}$) and incubated in the growth chamber at $25^{\circ}C$ and 65% RH, the light period was adjusted to 24 hours (day). NPK chemical fertilizer and trade product (EMRO, USA) of effective microorganisms as well as un-inoculated control were used for comparison. Plants harvested in 40 days were found to have significant increase in leaf chlorophyll units and plant height and also in dry weight of root and shoot in the inoculated seedlings. Root and shoot length and also leaf surface area significantly were increased by bacterial inoculation in sterile soil. The study suggests that Rhodobacter capsulatus and Azotobacter chroococcum are beneficial for B. rapa growth as they enhance growth and induced IAA production and phosphorus solubilization. This study presents some rhizomicrobial strains that significantly promoted growth of Wisconsin Fast Plant B. rapa in pot experiment under different soil conditions.

• STI Policy Review
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• 제3권1호
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• pp.46-62
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• 2012

This study investigates the effects of the two most important indicators of a nation's state of scientific infrastructure: R&D investment and the number of R&D researchers engaged in high-tech product export competitiveness for a panel of 11 countries/economies from East Asia from 1994 to 2010. A GMM panel estimation method was employed to account for the dynamic effect of trade and to control for un-observed country specific effects that may arise due to an inter-country differences and intra-country dynamics. Accordingly, the empirical results reveal that (once controlled for the influence of per capita income) physical capital and infrastructure, a 1% increase in a country's expenditure on the ratio of R&D to GDP may increase high-tech product export performance by approximately $397 million per year. Other factors constant, a 1% increase in the number of R&D researchers is expected to increase the ability to export high-tech products by approximately $67 million. The East Asian development experience demonstrates how latecomers can follow systematic industrialization and join the handful of economies that have come a long way toward closing the knowledge gap with the global technological leaders. However, this does not mean that the policy approaches and overall commitments pursued by each East Asian economy in relation to R&D investment and acquisition of an adequate pool of researchers, and their ultimate achievements in high-tech product export competitiveness were uniform. As a result, there is still a significant variation among countries/economies in terms of performance. This study recommended a number of potential tools and policy instruments that may assist policy makers to foster R&D as an engine to enhance the high-tech product export competitiveness.

• 한국재난정보학회 논문집
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• 제5권1호
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• pp.78-100
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• 2009

This study is to protect peoples' life, minimize the property damage by coping with threats quickly and take more preventive measures in advance against nuclear bomb, CBR, and potential explosive. For this, CBRNE(Chemical, Biological, Radiological, Nuclear, Explosive) program research was used. Thanks to advance in technology, terrorist groups and even individuals make or keep nuclear and CBR weapons. And also it's likely that disaster and threats from a toxic gas, acute pathogens, accidents in the nuclear power plants and a high explosive could be happened a lot. Recently more organized terrorist groups maintain random attacks for unspecified individuals and also it's highly likely that a large-scale terrorist attack by WMD and CBRNEwill be done. To take strict measures against CBRNE attacks by terrorists is on the rise as an urgent national task. Moreover biological weapons are relatively easy and inexpensive to obtain or produce and cause mass casualties with a small amount. For this reason, more than 25 countries have already possessed them. In the 21 st century, the international safety environment marks the age of complicated threats : transnational threats such as comprehensive security and terror, organized crime, drug smuggling, illegal trade of weapons of mass destruction, and environmental disruption along with traditional security threats. These cause military threats, terror threats, and CBRNE threats in our daily life to grow. Therefore it needs to come up with measures in such areas as research development, policy, training program. Major industrial nations on CBRNE like USA, Canada, Switzerland, and Israel have implemented various educational programs. These researches could be utilized as basic materials for drawing up plans for civil defense, emergency services and worldwide countermeasures against CBRNE.