• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.449-449
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• 2021

하천 내 오염물질 유입원은 하수처리장과 같이 농도를 예측 가능한 점오염원이 일반적이지만, 수질오염사고와 같이 다량의 유해물질이 일시에 하천에 유입되는 경우도 발생하곤 한다. 특히 오염물질 유입지점과 취수장이 인접한 경우, 오염물질 혼합해석에 대한 이해가 오염사고 대응 및 수질 관리 측면에서 매우 중요하다. 자연하천에서는 사행에 따른 유속 구조의 불균일성 등으로 인하여 오염물질의 이송 및 분산 과정은 매우 복잡하게 나타난다. 이러한 하천의 지형적, 수리학적 특성이 오염물질의 혼합 거동에 미치는 영향을 정확하게 모의하기 위해서는 3차원 수치모형을 적용해야 한다. 그러나 대부분의 하천은 하폭 대 수심비가 매우 크기 때문에 2차원 이송-분산 방정식을 지배방정식으로 채택하는 2차원 수치 모형이 널리 사용되어왔다. 2차원 이송-분산 방정식의 해석결과는 입력된 종, 횡 분산계수의 값에 따라 변화하기 때문에 정확한 혼합해석을 위해 분산계수의 결정이 매우 중요하다. 과거 연구에서는 횡 분산계수의 결정을 위해 기본 수리량을 이용한 경험식을 활용하여 계산한 바 있다. 종 분산계수의 경우에는 경험식의 산정에 필요한 충분한 실험 자료가 축적되어 있지 않아 이상적 흐름 상태를 가정하여 유도된 Elder의 이론식(Elder, 1959)을 사용해왔다. 하지만 많은 연구에서 이러한 Elder의 이론식이 종 분산계수를 과소산정 할 우려가 있다고 제시했다. 따라서 하천의 전단류 분산특성을 나타낼 수 있는 데이터 확보를 통해 종 분산계수의 경험식 산정 및 횡 분산계수의 정확도 향상이 필요한 상황이다. 본 연구에서는 기존 선행 연구에서 수행된 2차원 추적자실험 데이터의 확장을 위해 오버샘플링 기법을 적용하였으며, 이를 통한 머신러닝을 통한 분산계수 산정 가능성을 분석하고자 한다. 부족한 추적자 실험 데이터를 확장하기 위해 오버샘플링 기법 중 SMOTE 기법을 활용했다. 오버샘플링 기법을 이용하여 생산된 데이터의 신뢰성을 검증하였으며, 추후 머신러닝을 이용한 2차원 종, 횡 분산계수 산정에 대한 활용 가능성을 분석했다.

• International Area Studies Review
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• v.15 no.1
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• pp.367-389
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• 2011

This paper examines what factors contribute to the entry of foreign investors to Chinese commercial banks from 1996 to 2008. Empirical results show that using survival analysis, size, liquidity ratio and non-interest incomes are important to foreign investors. This indicates that as Chinese banking system opened, foreign investors invest in bigger but financially weak banks. For Joint-Stock commercial banks, foreign investors invest in banks whose asset qualities and non-interest incomes are low. But for City commercial banks, foreign investors invest in banks that are big but have low liquidity ratios. This results indicate that because City commercial banks operate in only one city, foreign investors require minimum bank size to operate in that city.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.5
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• pp.267-277
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• 2014

The conventional performance-based design method for the solid-wall caisson breakwater has been extended and applied to the perforated-wall caisson. The mathematical model to calculate the sliding distance of a perforated-wall caisson is verified against hydraulic experimental data. The developed performance-based design method is then compared with the conventional deterministic method in different water depths. Both the expected sliding distance and the exceedance percentage of total sliding distance during the structure lifetime decrease with decreasing water depth outside the surf zone, but they increase with decreasing water depth inside the surf zone. The performance-based design method is either more economical or less economical than the deterministic method depending on which design criterion is used. If the criterion for the ultimate limit state is used, the former method is less economical than the latter outside the surf zone, whereas the two methods are equally economical inside the surf zone. However, if the breakwater is designed to satisfy the criterion for the repairable limit state, the former method is more economical than the latter in all water depths.

• Journal of Technology Innovation
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• v.19 no.1
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• pp.145-175
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• 2011

The purpose of this research investigates the determinant factors of the joint technology development project performance between SMEs and universities. Reviewing existing papers we could categorize independent variables into three groups of partner characteristics, process management variables and relationship characteristics between partners. Three measures of satisfaction with the cooperation result, the intention of continuing relationship and the utilization of developed technology and product were used as dependent variable considering that we studied the joint projects of SMEs' involvement, short period and small scale. The data was collected by questionnaire survey mailed to the 1082 SMEs and university professors which executed the joint projects sponsored by Small Business Administration in 2009. We received 200 responses from SMEs, and 305 cases from professors among which 55 responses of each partner were on the same project. We analyzed the data sets individually, data of SMEs and that of universities with multiple regression analysis technique and also analyzed the common responses of 55 projects. Analysis results of the data from SMEs indicated that partners' expertise, facilities and equipment, communications, strategic importance, and trust were significant variables for the project performance. Analysis results of the data from universities showed that previous links, definition of objectives, strategic importance, trust and commitment were significant variables. Analysis results of combined data of 55 projects from SMEs and universities indicated that facilities and equipment, project management proficiency and commitment were significant variables.

• Journal of Digital Convergence
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• v.19 no.1
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• pp.199-209
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• 2021

The purpose of this study was to analyze the factors that affect the satisfaction of smart seniors using smartphone delivery applications. We established the hypothesis by dividing the factors that will affect the satisfaction of smart seniors using smartphone delivery applications into the characteristics of the delivery app and the personal characteristics of the smart senior. In order to verify the hypothesis, we surveyed adult men and women aged 50 to 65 years old who had experience using delivery apps, and we performed confirmatory factor analysis, correlation analysis, and path analysis to perform statistical processing for data analysis. The analysis results are as follows. First, we found that usefulness among the characteristics of delivery app had a statistically significant positive effect on the delivery app satisfaction of smart seniors. Second, we found that social empathy among the personal characteristics of smart seniors had a statistically significant positive effect on the delivery app satisfaction of smart seniors. Third, we found that delivery app satisfaction had a statistically significant positive effect on reuse intention. Based on research result, we suggested that in order to improve the satisfaction and use of delivery app by smart seniors, it is necessary to develop delivery app that can be usefully used by smart seniors and focus on social empathy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6D
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• pp.631-639
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• 2010

The layout of haul routes within a construction site of large complex projects needs to be carefully determined as the productivity of earthwork activity heavily depends on the efficiency of the layout and the routes are not likely to change once they are settled. This paper aims to provide a construction planner with a reliable framework to create an efficient layout of haul routes within a large complex construction site. To construct the framework, five factors affecting haul route layout and the productivity of earthwork activity are described along with the associated rules of thumb recommended by design and field experts. In addition, a methodology based on spatial analysis using raster format in GIS is proposed to further increase haul route efficiency. The proposed planning framework enables a construction planner to easily find a more reliable route layout by thoroughly considering the key factors prior to setting up an earthmoving plan.

• Korean Journal of Culture and Social Issue
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• v.24 no.4
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• pp.541-562
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• 2018

Conflict of interest (COI) is one of the dominant circumstantial factors of moral corruption across various fields. Several management strategies have been proposed to prevent self-interested decision making in COIs. Among these strategies, message persuasion has been considered as a practical and effective approach. Prior studies have found that framing and repetition are two of the major factors in the persuasion effect of message. However, their effect on moral decision making in COI has not been well explored. The purpose of this study was to compare the differential effects of positively framed message and negatively framed message, and secondly, to investigate how the effectiveness of persuasive message changes through repetitive exposures. A total of 63 participants were randomly assigned to one of 3 framing conditions: positive framing, negative framing, and no-message condition. Prior to the on-line experiment involving a consultation task, differently framed persuasive message were presented to the participants. This process was repeated four times in a row. The results showed that participants with positive-framing message were less likely to provide self-interested consultation than participants in the no-message condition. Also, a U-shaped quadric relation between repetition and self-interest consultation was found. Implications and limitations are further discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7231-7238
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• 2014

This study examined the effects of self-efficacy on career maturity in dental hygiene students, and whether there were differences in self-efficacy according to the existence or not regarding the certificate of qualifications, participating experience in vocational training competition and award one in the competition. The data was collected from a self-administrated questionnaire on dental hygiene students. The 435 students were selected for this study. The data was analyzed by descriptive analysis, Pearson Correlation, and multiple regression analysis. The results of this study were as follows. First, the task difficulty self-efficacy as a career decision, career independence, career certainty, and career preparation had a positive impact. Second, the self-regulation self-efficacy as a career independence, career confidence, career preparation, and career objectives had a positive impact. Third, the main career attitude and maturity factors affecting the efficacy of dental hygiene students was a career student independence, career preparation, and career certainty. The total explanatory power was 28%. As a result of this research, comprehensive implications were suggested to improve the career maturity and enhance the adjustment to college.

• Journal of the Korean Institute of Gas
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• v.22 no.5
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• pp.1-17
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• 2018

Related incidents and accidents are frequent after 2000 years, such as the outbreak of the Taian peninsula crude oil spillage and Gumi hydrofluoric acid leakage accident. In the wake of such environmental pollution accidents, Consensus has been formed to enact legislation on liability for the compensation of environmental pollution in 2014 and the rescue, and has been in force since January 2016. Therefore, in the domestic insurance industry, the introduced environmental liability insurance system needs to be managed through the standardization formula of a new insurance model for managing the environmental risk. This study has been carried out by the emergence of a safe insurance model with a risky nature of the risk type, which is one of the services of the knowledge base. The verification of the six assurance media on the occurrence of environmental pollution such as chemical, waste, marine, soil, etc. is expressed through semantic interoperability through this possible ontology. The insurance model was designed and presented by deducing the relationship between the amount of money and the amount of money that was written in the area of existing expertise, In order to exclude the possible consequences, the concept of abstract is conceptualized in the form of a customer, and a plan for the future development of an ontology-based decision support system is proposed to reduce the cost and resources consumed every year. It is expected that standardization of the verification standard of the mass of mass will minimize errors and reduce the time and resources required for verification.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.961-970
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• 2009

Over the last decade, interactive devices such as mobile phones have become complicated drastically mainly because of feature creep, the tendency for the number of features in a product to rise with each release of the product. One of the ways to reduce the complexity of a multi-functional device is to design it consistently. Although the definition of consistency is elusive and it is sometimes beneficial to be inconsistent, in general, consistently designed systems are easier to learn, easier to remember, and causing less errors. In practice, however, it is often not easy to design the user interaction or interface of a multi-functional device consistently. Since the interaction design of a multi-functional device should deal with a large number of design variables and relations among them, solving this problem might be very time-consuming and error-prone. Therefore, there is a strong need for a well-developed methodology that supports the complex design process. This study has developed an effective and efficient methodology, called CUID (Consistent Design of User Interaction), which focuses on logical consistency rather than physical or visual consistency. CUID deals with three main problems in interaction design: procedure design for each task, decisions of available operations(or functions) for each system state, and the mapping of available operations(functions) and interface controls. It includes a process for interaction design and a software tool for supporting the process. This paper also demonstrates how CUID supports the consistent design of user interaction by presenting a case study. It shows that the logical inconsistencies of a multi-functional device can be resolved by using the CUID methodology.