• Proceedings of the KSR Conference
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• 2004.10a
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• pp.868-873
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• 2004

Recently, The surface-wave method has widely been used for the site investigation due to the economic advantage and the improved reliability. The typical surface-wave methods currently available are SASW method, MASW method and CSW method. The CSW method has a potential of high-quality measurement, but its inherent problems limited its use to the special cases such as the compaction-quality control. The CSW method uses the steady-state harmonic vibration for the seismic source as in the steady-state Rayleigh-wave method, which is superior to the impact source used for other methods. This study proposed a new procedure to solve the inherent problems of the CSW method and to improve the reliability of the CSW measurements. To verify the validity of the proposed in this study, the SASW results were compared with the CSW results for the numerical simulation of the CSW testing. Also, the feasibility of the proposed method was verified using the field measurements at a geotechnical site.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.77-81
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• 2010

This study carried out hydraulic model test for water circulation system in Cheongna district as part of Incheon Free Economic Zone. Canal way project of Cheongna was planned to establish for environment-friendly water circulation system, improve quality of life and diversification of traffic through using boat as a water-friendly international business city. The navigation canal, There are two intake facility in central park and it can purify water 15,000$m^3$ per day. After purify, water move to 8 facility of water culture area which supplies water in canal way. This process called water circulation system in cheongna. Also, there are several flow induction machine in canal way except south-north way. Therefore, this study will verify about validity of water circulation system's safety through hydraulic model test.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.4
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• pp.579-589
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• 1998

Full turnover-based storage policy (FULL) is often used to minimize the travel time needed to perform storage/retrieval operations in automated storage/retrieval systems (AS/RSs). This paper presents an approach for determining the required storage capacity for a unit load AS/RS under the FULL. An analytic model is formulated such that the total cost related to storage space and space shortage is minimized while satisfying a desired service level. To solve the model, some analytic properties are derived and based on them, an iterative search algorithm which always generates optimal solutions is developed. To illustrate the validity of the approach, an application is provided when the standard economic-order-quantity inventory model is used.

• Industrial Engineering and Management Systems
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• v.11 no.1
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• pp.11-17
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• 2012

Along with the recent trend toward increasing variety and shorter life of products in the market, evaluation of risk for economic investment alternatives is of practical importance in manufacturing companies. This paper assumes that each alternative is composed of demand volume and unit sales price as income factors, and unit variable cost and fixed cost as expense factors. The paper assumes that these four factors move worse from the originally expected values, toward the direction of decreasing profit. Values of these four factors are also assumed to fluctuate from year to year over the entire multi-period. By applying the analysis of the breakeven points to each of the four factors, safer area against these changes is represented on the two dimensional domain called normalized total-cost unit-cost domain. A practical numerical example is analyzed to verify the validity of the proposed method.

• Communications for Statistical Applications and Methods
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• v.27 no.6
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• pp.589-602
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• 2020

The development of smart grids has enabled the easy collection of a large amount of power data. There are some common patterns that make it useful to cluster power consumption patterns when analyzing s power big data. In this paper, clustering analysis is based on distance functions for time series and clustering algorithms to discover patterns for power consumption data. In clustering, we use 10 distance measures to find the clusters that consider the characteristics of time series data. A simulation study is done to compare the distance measures for clustering. Cluster validity measures are also calculated and compared such as error rate, similarity index, Dunn index and silhouette values. Real power consumption data are used for clustering, with five distance measures whose performances are better than others in the simulation.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.11
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• pp.50-57
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• 1997

In order to make unmanned machining systems with satisfactory performances, it is necessary to incorporate appropriate condition monitoring systems in the machining workstations to provide the required intelligence of the expert. This paper deals with condition monitoring for chatter, tool wear and breakage during turning operation. To develop economic sensing and identiffication methods for turning processes, sound pressure measurement and digital signal processing technique were proposed. We suppressed chatter by stability control methodology, which was studied through manipulation of spindle speeds regarding to chatter frequencies. It was shown that tool wear and fracture were identified and to be estimated by using the wear indices. The validity of the proposed system was confirmed through the large number of cutting tests.

• Journal of Distribution Science
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• v.12 no.6
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• pp.31-39
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• 2014

Purpose - Environmental issues, climatic changes, and greenhouse gases are problems to be solved at a global level. With an increased emphasis on the environmental and social responsibility of the management of companies, the manner in which companies approach quality-oriented culture and their individual sustainability management are being discussed as truly important issues to help them secure their competitiveness and growth strategies. This study proposes strategic directions to help manufacturers not only in expanding their competitive quality-oriented company culture but also in strengthening their sustainability management abilities. This study conducts a literature review and empirical research to examine how significantly the variables of a quality-oriented company culture, customer-centered management, and process-centered and supply chain management-centered cooperation affect sustainability management performance in relation to economic profitability, environmental integrity, and social responsibility. Research design, data, and methodology - To verify research models and hypotheses, the study examined 170 companies using a questionnaire survey conducted over six weeks, and involved the performance of data analysis on 146 samples. Questionnaire responses were calibrated based on a Likert scale. The study used the Smart PLS 2.0 program designed for PLS (partial least squares), an analysis instrument of SEM (structural equation modeling). The study then verified empirical research hypotheses working on reliability analysis, validity analysis, factorial analysis, and path analysis. Results - Among the nine hypotheses, four are accepted and the rest are rejected. A quality-oriented company culture focusing on customer-centered management significantly influenced the maintainability management performance of environmental integrity and social responsibility, while economic profitability was dismissed. A process-focused quality-oriented company culture was significantly concerned with economic profitability but not with environmental integrity or social responsibility. A supply-chain cooperative company culture had a significant effect on economic profitability but not on environmental integrity or social responsibility. Conclusion - This study proposes strategic directions to help manufacturers expand their competitive quality-oriented company culture as well as strengthen abilities with sustainability management. It conducts a literature review and empirical research to examine how significantly the variables of quality-oriented company culture, customer-centered management, and process-centered and supply chain management-centered cooperation affect sustainability management performance in relation to economic profitability, environmental integrity, and social responsibility. There are two main conclusions. First, companies should consider the need for social responsibility management and environmental transparent management-focused maintainability management as avenues to create new markets and business, thereby helping the companies secure a reputation for having a customer and process-centered quality-oriented company culture by creating shared values between supply chains and enabling win-win situations through cooperation. Second, we are marching towards a creative win-win era from a society of conflicts and ruptures. Companies should understand that social responsibility management and supply chain management (SCM)-focused cooperation are the foundations of sustainable development, as they try to improve their culture while pursuing both win-win relationships with interested parties and equity in various conflictive relations.

• Journal of Korea Port Economic Association
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• v.31 no.4
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• pp.91-106
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• 2015

This study aims to analyze the effects of service quality offered by automotive Ro-Ro terminal operators on customer satisfaction and loyalty. The results of the research can be used to understand how to enhance the service level in order to manage competitiveness of the terminal operators, finally resulting in global competitiveness of the automobile industry of Korea in both exports and imports. We carried out a survey on two groups: shippers (customers) and providers (related terminal operators and stakeholders). To identify and classify the factors into groups, we conducted Exploratory Factors Analysis (EFA) and Confirmatory Factor Analysis (CFA), which showed construct validity and convergent validity. We also calculated Cronbach's alpha for reliability. Five factor groups were identified: tangibles, reliability, responsiveness, assurance, and empathy. We found that empathy is the most influential factor group among the five groups, and that the other groups too exhibited similar effects. Based on the results of the survey and analyses, we can conclude that empathy is most important in automotive Ro-Ro terminals. In particular, specialties, training, experiences, and loyalty of employees are crucial factors because automotive Ro-Ro terminals significantly rely on work forces, differently from other bulk terminals and container terminals. Flexible working hours and fringe benefits for work forces can increase empathy, finally resulting in productivity and efficiency. Next, well-designed work schedules are followed, based on visibility through logistics and SCM activities in automobile export and import processes with information and communication networks.

• Journal of Distribution Science
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• v.12 no.12
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• pp.43-54
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• 2014

Purpose - This study examines how perceived benefits and costs of traditional market support affect relationship quality and support for a marketeer. In addition, it investigates whether support for traditional market aid programs leads to support for the government. The author developed a structural model comprising several variables, in which perceived benefits and costs comprising economic, social, and environmental costs were proposed, to affect the relationship quality (satisfaction and trust) of traditional market aid programs and the government. Consequently, marketeers satisfied and trusted by traditional market aid programs and the government would support the traditional market aid program, resulting in higher support for the government. The model proposed that customer satisfaction would improve customer loyalty and business performance. Thus, the relationship quality (satisfaction and trust) of the traditional market aid program and government was proposed as a core mediating variable between perceived benefits and costs and support. Research design, data, and methodology - To analyze the proposed model, this study investigates the scenario with a traditional marketeer. Data were collected from 331 respondents, and analyzed with SPSS/PC 18.0 and AMOS 18.0. To test the unidimensionality and nomological validity of the measures of each construct, we employed a scale refinement procedure. The result of the reliability test with Cronbach's and confirmatory factor analysis warranted unidimensionality of the measures for each construct. In addition, nomological validity of the measures was warranted from the result of correlation analysis. Results - First, perceived benefit affects the relationship quality of traditional market aid programs and government. Second, perceived costs affect the satisfaction of traditional market aid programs and government. Third, the relationship quality of a traditional market aid program affects the support of a traditional market aid program, and the relationship quality of government affects the support of government. Finally, the support of traditional market aid program affects support of government. The results confirm the findings of previous studies that local development positively influences support, based on the social exchange theory. Conclusions - The theoretical and managerial contributions of this study are as follows. First, it is the first such study, and defines mediating variables, analyzing relationship quality (satisfaction and trust) between perceived benefits and costs and support for the traditional market industry. Further, it investigates the structural relationships between them with the AMOS program. Second, while most previous studies investigating the relationship between similar variables and those of the present study analyzed how perceived benefits and costs influenced support, this study identified the transfer relationship between the support for traditional market programs and support for the government. This study confirms that support for traditional market aid program increases support for the government. Therefore, government policy makers for traditional market aid programs should explain to marketeers the benefits and costs of traditional market development in terms of economic, social, and environmental factors. At the end, limitations, further research directions, and implications are suggested.

• Korean Journal of Social Welfare
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• v.61 no.3
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• pp.283-305
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• 2009

The purpose of this study is to develop a scale for the social network of college students in Korea. The social network scale for college students in this paper was developed through 1) literature review and item development 2) focus-group meeting 3) depth-interview with college students 4) pilot-studies and 5) study. The scale of 23 items has been constructed with three features : The first is 'relational feature' with 2 items; the second 'structural feature' with 7 items; and the third 'functional feature' with 14 items. The functional feature in this social network scale has consisted of emotional, economic, spiritual, and socio-relational aspects and has been revealed to the validity and the reliability of Cronbach's ${\alpha}$ 0.716. This study would contribute for college students to solve the many problems in their own lives through the social networks.