• Nuclear Engineering and Technology
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• 제51권2호
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• pp.337-344
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• 2019

The TRIGA fuel of the Philippine Research Reactor-1 (PRR-1) will be used in a subcritical reactor assembly (SRA) to strengthen and advance nuclear science and engineering expertise in the Philippines. SRA offers a versatile and safe training and research facility since it can produce neutrons through nuclear fission reaction without achieving criticality. In this work, we used a geometrically detailed model of the PRR-1 TRIGA fuel to design a subcritical reactor assembly and calculate physical parameters of different fuel configurations. Based on extensive neutron transport simulations an SRA configuration is proposed, comprising 44 TRIGA fuel rods arranged in a $7{\times}7$ square lattice. This configuration is found to have a maximum $k_{eff}$ value of $0.95001{\pm}0.00009$ at 4 cm pitch. The SRA is characterized by calculating the 3-dimensional neutron flux distribution and neutron spectrum. The effective delayed neutron fraction and mean neutron generation time of the system are calculated to be $748pcm{\pm}7pcm$ and $41{\mu}s$, respectively. Results obtained from this work will be the basis of the core design for the subcritical reactor facility that will be established in the Philippines.

• 대한조선학회논문집
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• 제46권6호
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• pp.659-666
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• 2009

Recently, there are several problems in space, contiguity and facility of the existing harbors issued due to the trend of enlarging the container capacity of the large container vessel, the Mobile Harbor has been proposed conceptually as an effective solution for those problems. This concept is a kind of transfer loader of the containers from the large container ship, which is a floating barge with a catamaran type in the underwater part, and so prompt maneuverability and work effectiveness. For the safe mooring of two floating bodies, a container and the mobile harbor, in the near sea apart from the quay, a robot arm mooring facility specially devised would be designed and verified through comparison study under various environmental sea condition in the inner and outer harbor. DP system (Dynamic Positioning System) using the azimuth thruster and a pneumatic fender, etc, will be considered as a next research topic for the mooring security of multi-body floaters.

• Safety and Health at Work
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• 제7권4호
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• pp.331-339
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• 2016

Background: Occupational risk management is known as a catalyst in generating superior returns for all stakeholders on a sustainable basis. A number of companies in Ghana implemented health and safety measures adopted from international companies to ensure the safety of their employees. However, there exist great threats to employees' safety in these companies. The purpose of this paper is to investigate the level of compliance of Occupational Health and Safety management systems and standards set by international and local legislation in power producing companies in Ghana. Methods: The methodology is conducted by administering questionnaires and in-depth interviews as measuring instruments. A random sampling technique was applied to 60 respondents; only 50 respondents returned their responses. The questionnaire was developed from a literature review and contained questions and items relevant to the initial research problem. A factor analysis was also carried out to investigate the influence of some variables on safety in general. Results: Results showed that the significant factors that influence the safety of employees at the hydroelectric power plant stations are: lack of training and supervision, non-observance of safe work procedures, lack of management commitment, and lack of periodical check on machine operations. The study pointed out the safety loopholes and therefore helped improve the health and safety measures of employees in the selected company by providing effective recommendations. Conclusion: The implementation of the proposed recommendations in this paper, would lead to the prevention of work-related injuries and illnesses of employees as well as property damage and incidents in hydroelectric power plants. The recommendations may equally be considered as benchmark for the Safety and Health Management System with international standards.

• Agricultural and Biosystems Engineering
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• 제3권2호
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• pp.73-78
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• 2002

Cabbage is one of the most important vegetable in Korea. The cabbage production was mainly based on human labor A comprehensive research fur substituting the human labor by machines has been performed until now. In general, cabbage is cultivated on hillside in Korea. Picking up the harvested cabbages in field and carrying to a vehicle fur transportation are very laborious work. Manual transportation of cabbage is likely to damage the quality and is also a cause to increase the cost of cabbage production. This study was to develop and evaluate a prototype cabbage loader fur efficient and safe transportation of cabbage. The developed loader was a semi-tracked vehicle operated by a hydraulic system, allowing the safe transportation and loading of cabbage in a steep field. The maximum loading weight of the loader was 1.0 ton. By using two sets of safety devices attached to the loader to avoid the roll-over in a steep field, the static rollover slopes were increased up to 34.0% and 37.4% fur the left and the rear direction, respectively The maximum field speed was about 6km/hr with two cabbage pallets of 750kg at a 25% inclined field. The loading capacity of the loader was about 35 pallets/hr when picking up, carrying, and unloading two cabbage pallets for one loading operation. The loading capacity was more than 8 times in comparison with the conventional human labor. The developed loader could be used fur loading and carrying the other vegetables. The study suggested a possible approach for designing the field machines operated on hillside.

• 정보처리학회논문지C
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• 제9C권3호
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• pp.367-374
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• 2002

IPsec은 인터넷에서 필수적인 암호와 인증 서비스를 구조적으로 제공하며, 동시에 안전한 키교환이나 재현공격 등을 방어할 수 있는 메커니즘을 제공하는 프로토콜로서, 현재 다양한 플랫폼에서 구현 중에 있다. 그러나 현재가지 IPsec엔진이 탑재된 서버들이 제대로 동작하는지 그리고 보안서비스를 적절히 제공하는지를 평가하기 위한 도구는 존재하지 않고 있다. 따라서 본 논문에서는 IPsec엔진의 보안성을 평가하기 위한 자동화된 규칙기반 보안평가 시스템을 설계 및 구현하였다. 본 시스템은 Widows와 UNIX 환경에서 수행이 가능하며 Java와 C언어로 구현되었다.

• International Journal of Computer Science & Network Security
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• 제24권3호
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• pp.53-58
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• 2024

The Internet of Things (IoT) enables the connection of millions of disparate devices to the World Wide Web. To perform the task, a lot of smart gadgets must work together. The gadgets recognize other devices as part of their network service. Keeping participating devices safe is a crucial component of the internet of things. When gadgets communicate with one another, they require a promise of confidence. Trust provides certainty that the gadgets or objects will function as expected. Trust management is more difficult than security management. This review includes a thorough examination of trust management in a variety of situations.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1676-1682
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• 2008

The vertical curve of railway is installed in changing point where the gradient is more than a certain degree to ensure safe operation of train and comfort of passengers. As a result of CAD work with 3D coordination by using the existing equation, it was found that the simple equation about vertical curve installation suggested in the surveying engineering or railway regulations did not reflect theoretical curvature of circular curve in a case of steep grade and large vertical radius. In this study, for derive precision equation and transition curve about vertical curve, gradient parameters, equation of circles and transition curve equation were used, and it was verified by CAD that the derived equation is exactly satisfied with parameters of geometrical circular and transition curve. This equation could be used to provide more smoothing operation of train and comfort of passengers on vertical curves, especially in case that railway requires precision vertical alignment of track such as super high-speed railway, LRT or Maglev system.

• 한국안전학회지
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• 제12권4호
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• pp.21-26
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• 1997

Korea Atomic Energy Research Institute (KAERI) developed a risk monitor called Risk Monster which supports for plant operators and maintenance schedulers to monitor plant risk and to avoid high peak risk by rearranging maintenance work schedule. Risk Monster can update the plant risk continuously according to the change of system/component configuration since Risk Monster reevaluates the plant risk based on the Probabilistic Safety Assessment (PSA) results. A brief description of Risk Monster is provided. The PSA model of UCN 3, 4 nuclear power plant was converted by KAERI to Risk Monster model. Using this Risk Monster model, a feasibility study of the on-line maintenance of an Essential Service Water (ESW) pump was performed. On-line maintenance of one ESW pump has been shown to be acceptably safe, and has economic benefits. In addition, it is not a violation of technical specification to continue plant operation with an out-of-service ESW pump.

• 대한안전경영과학회지
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• 제16권1호
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• pp.21-27
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• 2014

In this paper, a research was carried out to extract the more concrete and systematic method for the safety management of skyscraper construction. Here, the most risky processes in the construction of skyscrapers were extracted through the general risk evaluation for safety management processes and their characteristics and trends were analyzed for the suggestion of safety management methods and safety inspection factors in the construction of skyscrapers, as well as for the suggestion of prevention measures for major disasters. The result of this paper will be well used as a basic data in establishing the manual necessary for executing the construction of skyscrapers more safely than the present where there is no specific direction for the safe management of skyscraper construction yet.

• 한국지역사회생활과학회지
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• 제15권4호
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• pp.165-175
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• 2004

Food is very important for human being. It is not easy for us to enjoy good life because the situation of food is not good in Korea. The self-sufficient food rate is very low and most of food which we take was produced by industrial agriculture. Food of this kind has some problems with respect to the health of consumer, agriculture, environment and community. In order to secure the true food which is safe and environmentally sound, producers, consumers and community have to work together. Producers must engage in environmental agriculture. They must produce the true food and need to know regional consumers. Consumers must pay attention to the regional agriculture and must participate the production of true food. Local government must open farmers' markets for direct marketing between farmers and consumers. NGOs should educate and organize the producers and consumers.