• Tunnel and Underground Space
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• v.26 no.6
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• pp.455-465
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• 2016

The collapse of underground mine development void for mineral resources can cause the subsidence of ground surface. In order to prevent the subsidence of ground, data such as maps or pictures of past mining site is important information for current mine reclamation works. In particular, mine subsidence management was based on mining maps and pictures. The process of the mining area surveys, safety evaluation, and ground reinforcement are normally possible with information such as maps and pictures in past mining. During the Japanese colonial period and 1960's, a lot of mines were developed in Korea indiscriminately. However, mining information at that time is limited to use. In the future, mining information will become even more rare. MIRECO intends to establish a realistic alternative solution. In this study, the basic numerical information of developed mine tunnels in Korea is statistically reviewed, and advanced underground cavity measuring technology was studied. 4,473 mine tunnel opening data of 1,784 abandoned mines in korea were collected and sorted. As a result of the analysis, the average value of small mine tunnel openings in Korea was 1.982 m in height and 1.959 m in width. The mean value of shape factor was analyzed as 0.485. The summary of these numerical mine data will be helpful for understanding and researching Korean abandoned mines. Therefore, the development of measurement technology for abandoned mine cavities and tunnels is expected to facilitate more effective mine subsidence management works in Korea.

• Journal of agriculture & life science
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• v.53 no.5
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• pp.153-165
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• 2019

This paper analyzes the priorities of introducing agricultural environmental conservation practices for the successful introduction of agricultural environmental conservation programs and promotes customized agricultural environment conservation practices packages suitable for the local environment. Agricultural environmental conservation practice consists of three fields: soil, water, and air, nine sub-fields, and 30 practice skills. Using the advantages of AHP and BWS appropriately for priority analysis, three areas and nine sub-fields are measured using AHP techniques, and the practical activities of each fields are measured by priorities using BWS techniques to enhance the differentiation and completeness of research. In addition, the criteria for evaluating priorities of practical activities used 'Environmental effectiveness' and 'Technical feasibility'. As a result of the priority evaluation, the 'Soil testing and reduction of fertilizer and livestock manure application' activities were evaluated as having the highest priority. Based on the results of the priorities for these practical activities, examples of customized practical activity packages by farming type and environmental conditions were presented.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.137-150
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• 2015

This study investigated the influence of Entrepreneurship, Start-up Competency on Entrepreneurial Satisfaction and the moderating effect of Flow experience. The goal of this investigation is to empirically prove that despite the benefits of educational and financial support, mentoring and consulting which selected applicants received as a part of supporting business for start-up companies provided by national and local government and public organizations, there is a gap between individual entrepreneurs' satisfaction after actual foundation of the company. For the purpose of this investigation, data was collected through a survey with 320 entrepreneurs who were beneficiaries of government's supporting business for start-up companies and have founded their companies less than 5 years ago. For entrepreneurship variables, three factors of innovativeness, proactiveness and risk-taking were reviewed, and also reviewed the three variables network capability, market orientation and marketing capacity as Start-up competency. The collected data was used to perform a multiple regression analysis, and the moderating effect of flow experience was analysed using moderated regression analysis. The result of analysis shows that innovativeness, proactiveness and risk-taking of entrepreneurship positively affected the entrepreneurial satisfaction, and network capability, market orientation and marketing capability also positively affected the entrepreneurial satisfaction. As a result of analysing the moderating effect of flow experience, it appeared that there is a positive moderating effect between entrepreneurship, start-up competency, and the entrepreneurial satisfaction. This result concludes that evaluation items of entrepreneurship and start-up competency as applicant selecting criteria in supporting business for start-up companies, are valid. It is also concluded that start-up supports such as education, funds and consulting are also important, but it is necessary to make changes such as construction of start-up ecosystem and reinforcement of networking support, so that entrepreneurs can have the flow experience themselves in the process after founding a company.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.3
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• pp.255-262
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• 2011

In a loss-of-coolantaccident, considerable debris may be generated and transported to the recirculation sump. The accumulation of debris will reduce the netpositivesuctionhead and threaten the safety of thenuclear power plant. Both NEI 04-07 and USNRC SER suggesteda CFD methodology. However, additional investigation is needed to consider the unique characteristics of nuclear power plants. The transport of the generated debris is strongly influenced by the break location and the plant characteristics, including the configuration.In this paper, a CFD methodology for blow-down transport evaluation is proposed and applied to an OPR1000 nuclear power plant. The results show that the percentage of small debris transported to the upper containment is 32%, which is 7% larger than the valuegiven in the NEI 04-07 baseline analysis. This result may be used as a point of reference in future analytical studies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1054-1060
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• 2012

In order to analyze the influence of career self-efficacy on risk taking level in university students, career self-efficacy which becomes the basis of active occupational exploration was classified into four items including self evaluation, goal setting, occupational information and problem solving. Risk taking level was divided into three items of occupational selection, monetary management and human relation. 450 surveys were distributed to four-year university students in Seoul, capital area and rural area for three weeks from November 26 until December 17, 2011, among which 402 surveys were accepted as effective study subjects. Among items of career self-efficacy, most significant influence on self evaluation was shown in group with high risk taking level in monetary management, and problem solving had most significant influence in groups with high risk taking level in occupational selection and human relation. As a result, occupational information was found to have negative (-) influence on all items of risk taking level, with increasing degree of influence on occupational information for subjects showing lower degree of risk taking level. This study provides detailed analysis on individual's work task called risk taking level based on different occupational types, offering new verification of career self-efficacy as the most fundamental element of occupational exploration to university students looking for employment.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.11-19
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• 2009

At present, an intelligent transport system (ITS) is being actively introduced as an alternative plan to solve various transport problems, and a traffic information provision service, a field of ITS, is being provided to users through diverse media. However, the evaluation of how useful the traffic information provided to the road users is limited to a simple questionnaire, and the systematic evaluation about what factors affect the usefulness of traffic information has not been realized. Therefore, it is impossible to calculate user convenience occurring due to traffic information, This paper aimed to develop an index to evaluate user satisfaction levels with traffic information and develop a user satisfaction level model. A result of establishing a user satisfaction level model by executing a questionnaire survey for the analysis object of variable message sign (VMS), a representative information provision medium, showed that 'desire satisfaction', 'trust', 'understanding', and 'efficiency' have an effect. Of them, the 'understanding' showed the highest level, so it was seen that, in case of VMS, how easily the character, figure, expression, etc. provided in the information was understood by users has the biggest effect on the satisfaction level of the information. The next levels of effects on the satisfaction was in the order of 'user trust', 'efficiency', and 'desire satisfaction'.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.77-84
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• 2020

In this paper, we developed a damage evaluation technique that can determine the damage location of a long-sized structure such as a cable-stayed bridge, and verified the performance of the developed technique through experiments. The damage assessment method aims to extract data that can evaluate the damage of the structure without the undamage data and can determine the damage location only by analyzing the response data of the structure. To complete this goal, we developed a damage assessment technique that considers variability based on the IMD theory, which is a statistical pattern recognition technique, to identify the damage location. To complete this goal, we developed a damage assessment technique that considers variability based on the IMD theory, which is a statistical pattern recognition technique, to identify the damage location. To evaluate the performance of the developed technique experimentally, cable damage experiments were conducted on model cable-stayed bridges. As a result, the damage assessment method considering variability automatically outputs the damageless data according to external force, and it is confirmed that the performance of extracting information that can determine the damage location of the cable through the analysis of the outputted damageless data and the measured damage data is shown.

• Journal of Conservation Science
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• v.36 no.6
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• pp.505-510
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• 2020

In this study, the anti-stain effect of the Traditional Myoung-oil, which has been reproduced through traditional method, the Clean Myoung-oil, which was developed in an eco-friendly method through scientific analysis of Traditional Myoung-oil, and the perilla oil, which is the raw material of Myoung-oil and is currently used as a finishing agent when repairing wooden cultural properties was evaluated. As a result of the evaluation, perilla oil showed almost no anti-stain effect, whereas both types of Myoung-oil showed high anti-stain effect. However, it was confirmed that the anti-stain effect was significantly reduced after 4 weeks of exposure to the strain when Myoung-oil was diluted with terpene oil, a natural solvent. Thus, it was considered that the amount of treatment in the wood affected the anti-stain effect of Myoung-oil. In other words, in constructing wooden buildings, Myoung-o il is more suitable as a finishing agent to suppress mold growth than perilla oil. And, in order to increase the applicability of Myoung-oil, it is suggested that additional research on the optimal treatment amount and treatment method that can inhibit mold growth inhibition in outdoor environments is necessary.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1C
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• pp.63-72
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• 2006

Due to rapid development of many cities in Korea, many public facilities are required to be built as well as complementary civil structures. Consequently, a number of tunnel constructions are currently carried out throughout the country, and many more tunnels are planned to be constructed in the near future. Tunnel excavation in a city often causes serious damage to above-ground structures and sewer system because of unexpected settlement. In order to prevent the destruction, the tunnel, which bypasses the center of a city, must be specially evaluated for its influence to other structure. In addition, since a slight disturbance of above-ground structure causes numerous public complaints and civil appeals, it must be approached with different method than the mountain tunnels. In this paper, the evaluation method using the Artificial Neural Network (ANN) has been studied. The method begins with an analysis of the minimal sectional area. If its result can be used to approximate the general influence of the whole section, the actual evaluation using ANN will take off. In addition, it also studies the construction management method which reflects the real time soil behavior and environment influence during construction using Geographic Information System (GIS).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4D
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• pp.539-546
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• 2011

Traffic accident collision interpretation is composed of various shapes, and speed variations working to the vehicle during collision are utilized as a very important factor in evaluating collision degrees between vehicles and safety of passengers who got in the vehicle. So, methods of interpreting results on speed variations utilizing simulation programs on the collision interpretation become necessary. By the way, reliability evaluation on each program is being required because various collision interpretations simulations are spread widely. This study utilized collision interpretation programs such as EDSMAC and PC-CRASH adopting completely different physical approaches, and then carried out collision experiments of one-dimensional front and two-dimensional right angle while changing values of a lot of collision factors such as vehicle's weight, center of gravity, rolling resistance, stiffness coefficient, and braking forces among early input conditions. Also, the study recognized effects of collision factors to speed variations as output results during crashing. As a result of this research, two simulation programs showed same speed variations together on the vehicle's weight, center of gravity, and braking forces. Stiffness coefficient of the vehicle reacted to EDSMAC only, and rolling resistance coefficient did not affect any particular influences on speed variations. However, there appeared a bit comparative differences from the speed variation's values, and this is interpreted as responding outcomes by applying fixed properties values to each simulation program plainly. Therefore, reliability on analysis of traffic accident collisions shall be improved by doing speed analysis after taking the fixed value of simulation programs into consideration.