• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.147-152
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• 2015

In order to develop the cooling load estimation method in the greenhouse, the cooling load calculation formula based on the heat balance method was constructed and verified by the actual cooling load measured in the fog cooling greenhouse. To examine the ventilation heat transfer in the cooling load calculation formula, we measured ventilation rates in the experimental greenhouse which a cooling system was not operated. The ventilation heat transfer by a heat balance method showed a relatively good agreement. Evaporation efficiencies of the two-fluid fogging system were a range of 0.3 to 0.94, average 0.67, and it showed that they increased as the ventilation rate increased. We measured thermal environments in a fog cooling greenhouse, and calculated cooling load by heat balance equation. Also we calculated evaporative cooling energy by measuring the sprayed amount in the fogging system. And by comparing those two results, we could verify that the calculated and the measured cooling load showed a relatively similar trend. When the cooling load was low, the measured value was slightly larger than calculated, when the cooling load was high, it has been found to be smaller than calculated. In designing the greenhouse cooling system, the capacity of cooling equipment is determined by the maximum cooling load. We have to consider the safety factor when installed capacity is estimated, so a cooling load calculation method presented in this study could be applied to the greenhouse environmental design.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.681-688
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• 2018

As environmental regulations have been strengthened and high fuel efficiency has been in demand in recent years, the number of ships using natural gas as a fuel is increasing. The demand for ships using LPG or methanol, which are emerging as eco-friendly vessel fuels, is also increasing. In this perspective, ME-LGI engines using LPG or methanol as a fuel have attracted considerable attention. Ships equipped with an ME-LGI engine are required to check the reliability of the fuel injection valve during shipping. This means that the development of a fuel injection valve tester is essential for the commercialization of ME-LGI engine. This study conducted the conceptual design of a fuel injection valve tester for ME-LGI engines using a system engineering process in the order of requirements analysis, functional analysis, and design synthesis. In the requirement analysis stage, the operating process of fuel injection valve was analyzed, and the necessity of checking the sealing oil leakage was then derived. In the functional analysis stage, the functions and flow of them were defined at each functional level. In the design synthesis stage, the equipment for each function was set and the process block diagram based on it was derived. In addition, preliminary risk analysis was performed as a part of system analysis and control, and safety measures were added to the conceptual design. This study is expected to be a good reference material for the concept design of other systems in the future because it shows the application process of a system engineering process to the conceptual design in detail.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.469-475
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• 2010

The railway signalling system plays an essential role in the safe and efficient train operation as serving control functions of train operation intervals and train routes. The reliability and safety of the system are very important because the failure of the railway signalling system can lead to train collision or derailment as well as train operation stop. Until now, in railway signalling system the conventional wayside signal mode has been used generally. There are, however, the risk of accidents such as human mistakes caused by that the driver identifies the signal lamp status and controls train speed with the naked eye. It is also necessary to refurbish the obsolete system. Thereby, It is being effective that the onboard signal mode has been recently introduced and applied in order to transmit the speed control information to train by using the computer and communication equipment. It is necessary to switch over the system in a way while providing passengers with an operation service to replace the obsolete signal system. In this paper, we verify the cases through trial assessment which are solved by the way of adding specific functionalities in the problems of interference among the procedure of switch-over processes and a serial of processes for system verification while a train is operated in the new system in parallel to the existing system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5861-5869
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• 2014

Existing studies of building exterior materials have focused on the colors or textures of cladding, and in terms of a design planning approach, have focused on the use of the environment and equipment and fire safety topics from an engineering perspective. As a result, little research has been done on performance guidelines for exterior materials, specifically according to the building type. Research into eco-friendly cladding materials is also in the rudimentary stage in a practical sense. In this study, the use of exterior materials over the last ten years in domestic construction was analyzed. The usage status of building exterior materials was evaluated quantitatively by frequency analysis, and its environmental performance is proposed through complex (qualitative + quantitative) analysis. The average value of the exterior material type number used for all analyzed buildings was 2.59. Glass, metal, stone, resin, cement, wood, and clay were used in that order with regard to the usage status. The analysis found that five of the materials satisfied the high efficiency and eco-friendly grading in terms of the four characteristics of an eco-friendly exterior. A list of eight eco-friendly elements was also proposed. The eco-friendly elements and characteristics of the exterior materials were derived to provide basic guidelines for domestic construction companies and design offices.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.258-274
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• 2010

Along with hardware implementation of cultural arts, the importance of cultivating and securing professionals who are able to operate and mange it from the political perspective is highlighted as a political issue. In addition, with growing public demand for culture, performing arts are enlarged and professionalized, and this increased the number of large-scale musicals and activated exchanges with overseas performances, which raised the demand for personnel of performing technology. Like this, growing theaters require professionals in the performing technology field for technically safe and quality performance. The certification system for performing arts professionals is to develop quality of theaters and performing arts by increasing vocational professionalism and safety in the performing technology field. This system performed since 2000 is getting positioned, and employees who worked for the performing technology field at this time showed a lot of attentions with certainty they would receive credit for artistic professionalism and raise pride as a performing arts professional. However, the government's political strategy to secure professionals of cultural arts and interest in human resource(HR) policy in the performing arts field were relatively insufficient. Therefore, this study examined the problems by looking into actual conditions regarding operation and role under the initial purpose of the certification system, and purposed the improvement plan as a first certification system to cultivate Korean performing arts professionals.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.269-274
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• 2004

The marine electronic system for safe navigation such as ECDIS has been contributing to increase the safety of navigation, decreasing the mariner's load of navigation. The ECDIS should be developed and approved by international standard of IMO for performance standard and IEC for type-approval method and required results. However, these standards have some ambiguities for us not to directly adopt them for real approval system, so we should analyze them for more clear meaning and prepare our own detail standard for type-approval system. The first thing to do for the goal of this research was to analyze the standard in detail and make ambiguity be cleared in our own standards, considering each test item in view of test methodology. For the result of analysis we could develop more evident and detail type-approval standard for each test item with test technology needed. Especially, we developed the colour differentiation test process of ECDIS monitor, which include the colour differentiation formula derived from CIE colour scheme. Several test items require sensor informations of navigation equipment compatible with IEC 61162. We also developed the signal simulator for general messages of IEC 61162 that must be provided. Additionally, the type-approval processes and standards for Back-up arrangement and RCDS mode were developed.

• Food Science and Preservation
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• v.19 no.1
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• pp.62-66
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• 2012

With the rapid growth of fresh-cut produce market, the South Korean fresh-cut industry is facing the challenge of ensuring food safety. As the estimation of the microbial numbers in fresh-cut produce processing lines (tools, and equipment) using the conventional microbiological techniques takes days, so there is a need for faster and easier monitoring methods. This study was conducted to investigate the use of ATP bioluminescence assay to measure the degree of microbial contamination from three actual fresh-cut processing lines. The samples collected from frech-cut vegetables, and fresh-cut fruits processing plants were tested for the estimation of the bacterial number, using the ATP bioluminescence and microbiological methods. The result of former was transferred to log RLU/100 $cm^2$, and that of the latter was transferred to log CFU/100 $cm^2$. A positive linear correlation between the ATP bioluminescence assay value and aerobic-plate count was found for fresh-cut processing lines, with a correlation coefficient of 0.8772 (n=50). The results of this study indicate that ATP bioluminescence assay can be used to monitor microbial contamination in fresh-cut produce processing plants, and can help improve the hygiene therein.

• Journal of Korea Port Economic Association
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• v.36 no.2
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• pp.1-18
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• 2020

The Internet of things (IoT) has been applied to a variety of industrial uses such as public service sectors, medical industries, automotive industries, and so on. Led by smart cities, this is typical. However, from a logistics perspective, the level of application is insufficient. This study examines the applicability of IoT-related technology in a container terminal, an object of the present invention, to derive an applicable plan. Analytic network process (ANP) analysis reveals the following results for IoT applications in container terminals: operating systems (26.7%), safety/environmental/security systems (26.4%), equipment maintenance systems (25.3%), and facility maintenance systems (21.6 %). The second ANP analysis reveals the following results: Economy (40.2%), productivity (21.1%), service level (19.5%), and utilizing technology level (19.2%). The application or standard of evaluation is important when applying IoT technology to container terminals; however, it is not concentrated in a certain area. It is desirable to build each container system with linkage and efficiency from a macroscopic view.

• Journal of the Korean Geotechnical Society
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• v.34 no.4
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• pp.13-25
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• 2018

When deformation occurs on slope reinforced with anchor, shear stress and bending stress are applied on the shear surface along the slip surface and increase of the shear deformation causes the tension force variation of the anchor. In this study, shear test was performed by measuring the tension force of the anchor by inducing shear deformation in vertical direction of the anchor using a large-scale direct shear test equipment in order to confirm the tension force variation of the anchor induced by shear deformation. The shear test was performed for 8 conditions which were classified according to the anchor reinforcement, separation distance (1D, 2D, 4D) from the shear surface to bonded part and the lateral-pressure condition (0.1 MPa, 0.2 MPa) of adjacent ground. As a result of the shear test, it was found that the separation distance and the lateral-pressure condition affect the shear force of the ground reinforced by anchor and the tension force of the anchor, and experimentally verified that the shear force variation is related to axial force variation of the anchor head and tip. Therefore, it was confirmed that the behavior of the bonded part induced by the shear deformation can be indirectly predicted by analyzing the tendency of the tension force variation of the anchor head.

• Journal of the Korea Convergence Society
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• v.8 no.10
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• pp.105-114
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• 2017

The purpose of this study was to examine the convergent awareness of emergency medical technicians serving as paramedics on the standard operating procedure(SOP) and their performance of it. The subjects in this study were 400 selected emergency medical technicians who were working as paramedics, and SPSS 20.0 was employed to make an analysis. The findings of the study were as follows: As for the convergent awareness of the subjects, they were best aware of the prevention of respiratory infections, and they were least aware of hand hygiene. Concerning performance, they performed best in handling treatment equipment and ensuring staff safety, and they performed least well in terms of hand hygiene. Overall, they were rated higher in awareness than in performance. Second, regarding the influence of general characteristics, there were statistically significant differences in awareness according to age, gender and injury experience, and significant differences were found in performance according to career only. The convergent awareness of the emergency medical workers was positively correlated with their performance. Given the findings of the study, it's required to improve both the Standard Operating Procedure awareness and performance of emergency medical workers who serve as paramedics, and it's expected to make it possible to boost their performance when repeated education is provided with the kind of programs that aim at improving awareness.