• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.146-156
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• 2017

In this study, the causal relationship between the main factors influencing the import of agricultural products and the changes in agricultural imports was investigated. In addition, we compared the magnitude of the impact of each factor on the changes in agricultural imports. It was found that the import liberalization rate, which represents the FTA factors and reflects the per capita GDP, the conditions of supply and demand of agricultural products in exporting countries and the changes in exchange rates, affects the changes of the agricultural products imports. However, the factors affecting the change of the imports by agricultural product category and the magnitude of the influence by each factor were different. This shows that various factors, other than the FTA factors, are compounding the changes in the agricultural imports. In the future, the market openings due to the implementation of the FTA will be further enlarged and the economic territory of the FTA will be further expanded, due to the implementation of additional FTAs, and the changes in the imports of agricultural products will cause damage to the domestic agricultural sector.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.245-250
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• 2017

Flash floods is defined as the flooding of intense rainfall over a relatively small area that flows through river and valley rapidly in short time with no advance warning. So that it can cause damage property and casuality. This study is to establish the flash-flood warning system using 38 accident data, reported from the National Disaster Information Center and Land Surface Model(TOPLATS) between 2009 and 2012. Three variables were used in the Land Surface Model: precipitation, soil moisture, and surface runoff. The three variables of 6 hours preceding flash flood were reduced to 3 factors through factor analysis. Decision tree, random forest, Naive Bayes, Support Vector Machine, and logistic regression model are considered as big data methods. The prediction performance was evaluated by comparison of Accuracy, Kappa, TP Rate, FP Rate and F-Measure. The best method was suggested based on reproducibility evaluation at the each points of flash flood occurrence and predicted count versus actual count using 4 years data.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.3
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• pp.18-31
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• 2018

Since accidents of hazardous material transport vehicle on roadways cause severe damage in the form of disaster, foreign countries have long been engaged in systematic management and establishment of relevant laws and policies for the road safety. Recently, over 10-kilometer long tunnel, such as Inje-Yangyang Tunnel and Geumjeongsan Tunnel, has been opened on the expressway and the production of various hazardous materials is increasing with the development of chemical technology. However, road laws related to the safe operation of hazardous materials transport vehicles are still lacking, and policy measures for managing them have not been specified. It is an important task to recognize the risk of accidents of hazardous material transport vehicles and to secure road safety by establishing a management plan for road managers. Therefore, this study analyzed the feasibility of the traffic regulation of expressway tunnel in South Korea and suggested a direction for management. The results of this study can be utilized as the primary data for the revision of law related to hazardous materials transport vehicles on roadways and the derivation of optimal route of hazardous materials transport vehicles.

• Archives of Plastic Surgery
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• v.37 no.2
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• pp.122-128
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• 2010

Purpose: Many descriptions of the digital arterial anatomy including skin territory of the finger have been published. Relatively few studies on venous architecture of the finger have been performed in this area, in part, attributable to the technical difficulties encountered in dissecting small vessels. The purpose of this study is to present the precise microsurgical anatomy of the vein related to the digital artery and venae comitantes of the components. Methods: Arterial and venous anatomy of their relation to the fingers were examined in 38 specimens of two fresh cadavers and 36 clinical cases. All specimens were evaluated grossly, surgical microscopically, or / and light microscopically to observe the three & two-dimensional structure of the artery and joining vein, evidence of the venae comitantes, and venous valve. Results: No longitudinal venae comitantes along the digital artery were found in any specimens. The size of the venae comitantes of each digital artery was much smaller than other vein, but always existed any level of digital artery. One or two venae comitantes in the digital artery ran spiral, oblique, helical, fibrillar, or irregular branched shape. The authors also found the vein of the finger, that had bicuspid valves, but not in venae comitantes. Conclusion: Recently, venous outflow problem rather than arterial circulation is the most common cause tissue failure after microvascular surgery in the hand. Sometimes, if it is not recognized early, there is an increased risk of tissue damage and loss. The authors concluded that this study presents a useful knowledge for the characterization of the venous structure and evidence for venae comitantes like a venule in the digital artery at varying levels of the finger.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.7
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• pp.854-867
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• 2014

In the circumstance that high oil price state is continued over the world, the investment in crude oil development by oil major is a trend of increasing. Recently the number of delivered drill-ship for 5 years has been sharply increased all over the world and about twice than that of past 30 years. As addition to the increase of the drill-ship demand, the operation of drill-ships which is delivered recently is about 3,000 meters, ultra deep sea, on average and the work area is expending. Accordingly the drilling system including the size and length of pipe for drilling has been bigger and bigger and the power supply equipment for operation system also has large capacity. Unlike merchant vessel, high power and high voltage of diesel generators are required for drill-ship for which the demand for V-type 320 bore of diesel generator has increased. It is on the raised that the importance of lubrication oil cleaning for diesel generator on drill-ship which has longer time for construction, and also long term low load operation is unavoidable during commissioning of equipments. Recently it was reported that engine crankpin was damaged due to the hard contact caused by the abnormal wear down(Cam wear) on crankpin and bearing. The same pattern of wear down was found through the inspection on series vessels and the other vessel under commissioning. The purpose of this paper is to analyze of the wear mechanism based on the observation and theories and objective research from actual cases and to prepare the counter measures to avoid foreseeable damage when the lubricating oil is not properly cleaned.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.4
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• pp.374-382
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• 2009

Steam generator(SG) tube, as a barrier isolating primary to the secondary coolant system of nuclear power plants(NPP), must maintain the structural integrity far the public safety and its efficient power generation capacity. And SG tubes bearing defects must be timely detected and taken repair measures if needed. For the accomplishment of these objectives, SG tubes have been periodically examined by eddy current testing(ECT) on the basis of administrative notices and intensified SG management program(SGMP). Stress corrosion cracking(SCC) on the SG tubes is not easily detected and even missed since it has lower signal amplitude and other disturbing factors against its detection. However once SCC is developed, that can cause detrimental affects to the SG tubes due to its rapid propagation rate. Accordingly SCC is categorized as prime damage mechanism challenging the soundness of the SG tubes. In this study, reproduced EDM notch specimens are examined for the detectability and quantitative characterization of the axial ODSCC by +PT MRPC probe, containing pancake, +PT and shielded pancake coils apart in a single plane around the circumference. The results of this study are assumed to be applicable fur providing key information of engineering evaluation of SCC and improvement of confidence level of ECT on SG tubes.

• Journal of Korean Society of Steel Construction
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• v.24 no.6
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• pp.613-625
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• 2012

Since railway bridge frequently have a chance of passing train load close to design load, it is necessary to reflect sufficiently fatigue property in early design phase for many structural details. Nevertheless fatigue cracks are reported partly in deck plate girder of railway steel bridge because of the weight and arrangement of axial load acting on railway bridge, the application of improper structural details for fatigue problem etc.. One of main cause for fatigue crack at the welded part of upper flange and web is caused by the eccentricity action of train load due to the difference of center to center spacing between the main girder supporting sleeper and the rail acting train load. For the existing deck plate girder of railway steel bridge, in this study, field survey, field measurement and a series of structural analysis were performed. In addition, the characteristics of structural behavior, the causes and repair/ retrofit of fatigue crack were examined in the target bridge.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.9
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• pp.482-496
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• 2016

Algal blooms of cyanobacteria (blue-green Algae) due to the eutrophication of rivers and lakes can cause not only the damage by its biological toxins but also the economic loss in drinking water treatment. The natural algae coagulant, a commercial product known as W.H. containing the algicidal and allelopathic material derived from oak, can control algal problems proactively through the coagulation flotation process. However, because there have been no applications of the process for pre-treatment in drinking water plants, we could find no report on the optimum injection dose of W.H.. In this study, we have conducted several sets of jar-tests while changing W.H. dose and concentration of chl-a for (1) Han-river samples and (2) subcultured cyanobacteria samples, and monitored the removal mechanisms of algae intensively. Based on these jar-test results, two linear equations with variables of chl-a and turbidity have been deduced to predict the optimal W.H. dose after the multiple regression analysis using IBM-SPSS. Also, prototypes of automatic control logic have been suggested to inject the optimal W.H. dose promptly in response to the variation of water quality.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.403-412
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• 2019

The characteristics of the manoeuvring motion of a ship are dependent on the ship type, as well as draft or speed in the same ship. In recent years, the number of extra-large vessels has increased significantly, which can cause enormous material and environmental damage in the event of a marine accident. Thus, the importance of ship maneuvering is increasing. The IMO has forced the officers to be trained in simulators through the STCW 95 amendment. However, FMSS is costly and difficult to access and the PC-based simulator has the disadvantage that only one person can engage in simulation. The purpose of this study was to solve the shortcomings of the FMSS and PC-based simulators by enabling multiple people to use their PCs to simulate based on a network. The simulator is implemented through the analysis and numerical calculation of the Nomoto model, Radar function mounting, data transfer protocol design, and GUI building. To verify the simulator, the simulation results were compared and analyzed with the test results of T.S. HANBADA according to the criteria of the Korean Register of Shipping(KR) and IMO standards for ship maneuverability. As a result, It showed a relative error of 0%~ 32.1% with an average of 13.7%, and it satisfied the IMO criteria for ship maneuverability.

• The Journal of Society for e-Business Studies
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• v.20 no.2
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• pp.27-36
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• 2015

Current leakage of industrial technologies with revealing state secret against nation is gradually increasing and scope of the spill is diversified from technology-oriented leakage to new economic security sector like information and communication, electrical and electronic, defense industry, illegal export of strategic material, economic order disturbance by foreign country, infringement of intellectual property, etc. So the spill damage can affect not only leaked company but also national interests and entire domestic industry. According to statistics from National Industrial Security Center of National Intelligence Service, a major cause of technology leakage is not only by external things about hacking and malignant code, but internal leakage of former and current employees account for about 80%. And technology leakage due to temptation of money and personal interests followed by technology leakage of subcontractor is steadily increased. Most studies in the field of security have tended to focus on measuring security capability of company in order to prevent leakage core assets or developing measurement Indicators for management rather than security activities of the company members that is most important. Therefore, this study analyzes the effect of most underlying security education in security activities on security capabilities of enterprise. As a result, it indicates that security education have a positive(+) correlation with security capabilities.