• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.263-281
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• 2017

Global optimization that considers the processes at integrated steel mills is more important than the local optimization to improve the efficiency of a single process. Research utilizing mathematical models at integrated steel mills predominantly focus on solving problems solely for a specific process or focusing on what techniques are applied to. However, it is important to define the problems that must be solved at the steelworks, identify the objectives and constraints that can be modeled, and selection of methodologies that can be applied to the problems. The purpose of this study is to investigate the problems in improving efficiency at integrated steel mills from the viewpoint of production & operations management. We review the research have been conducted in order to solve those problems. We classified the research into 6 categories and suggested future research direction based on the global optimization. It is expected that research themes for improving the efficiency at integrated steel mills will be derived.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.3
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• pp.179-192
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• 2007

Based on ontologies, semantic Web services enable the discovery, selection, and composition. OWL-S is a do facto standard ontology for describing semantics of Web services. Due to the difficulty of the OWL-S grammar, the teaming curve for constructing OWL-S description manually can be steep. This paper presents an efficient method for generating OWL-S descriptions from UML diagrams, which are widely used for software design and development. The proposed method is based on UML profiles to generate an OWL-S ontology from sequence or activity diagrams, which represent the behavior of a business process. Specifically, an XMI file extracted from UML diagrams is transformed into an OWL-S description via an XSLT script. Experimental results with a large volume of UML diagrams show that the proposed method deals with the control flow of complex processes and is superior to previous methods.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.44
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• pp.257-279
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• 2009

The underlying purpose of this paper is to interest scholars in 'Trade English'. 'Trade English' has to be recognized as one area of 'International Trade' disciplines and more studies have to be carried out with more attention from the scholars. Although there are many areas to be dealt with in 'Trade English', this paper discusses about the syllabus design of 'Trade English' from an educator's point of view. First of all, this paper reviews some theoretical background researches about needs analysis and syllabus design in 'Trade English' teaching and learning as ESP. With a systematic structure under the decent syllabus, selection and sequence of contents get clear and easier. Secondly, along with the rationals based on theoretical researches, how these theories are being or can be applied to the real classroom are discussed for further studies. A different syllabus would be designed according to needs analysis. In reality, the syllabus for practitioners who are doing their jobs in International Trade areas has to be definitely different from the one for pre-practitioners who are studying in International Trade areas at the tertiary education level. Namely, different learners present different needs and different needs make up the different syllabus. In order to provide these learners with the syllabus which can address their own needs, more researches or studies have to be done in the future. Since 'Trade English' is the discipline where two areas-International Trade and English as a second/foreign language-are mixed, the researches or studies also have to be carried out collaboratively by scholars from both areas.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.12
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• pp.2379-2386
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• 2016

This study conducted an analysis using IPA metrics targeting college students to get strategic implications for marketing in the recently fast-growing mobile shopping market. The IPA analysis result about the selection of mobile shopping malls is as follows. First, out of the 21 features, 'reliability of the offered products(6.09)' had the highest level of importance and 'convenience of payment(5.29)' had the highest level of performance. Second, in the area of 'Doing great, Keep it up' 11 features were included such as 'convenience of payment' and 'reliability of the offered products'. Third, the feature that needed to be corrected in the area of 'Focus here' was 'shortening the waiting time for exchange, refund or warranty service'. Fourth, low priority areas in terms of importance and performance, there were 3 features including 'push/notification helps purchases'. Fifth, to the area of 'overdone' 4 features belonged such as 'variety in the type of products'.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.218-229
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• 2015

While promoting a variety of projects by using sea space, there has been a lot of social controversy among the stakeholders based on the results of the analysis. In particular, the benefits of fisheries sector were over-estimated and occurred a lot of opposition from fishermen and environment groups. In order to this solve, we have been studied focussed such as excavation of new projects, the method and result of the estimated benefits for fisheries sector. With regard to the tidal power plant of Garolim, we came up with five kinds of problems such as doing not reflect of the cost of the initial investment, over unit production, over unit price, excessive selection of breed, issues of cost of production in benefits study of fisheries sector derived previously. In order to these problems, we have derived new profitable projects based on the initial materials such as improvement of raising breed, discharge project of fingerlings and a small sea ranch project. As a result, previous study was analyzed in 30.2 billion won(1993), 54.8billion won(2009), but this study was estimated to 26.4 billion won and differences of benefits amount were occurred. In a previous study was calculated benefits by simple method, but this study came up with new projects for fisheries sector and because we estimated benefits considering new project. The method for benefits calculations for fisheries sector was not attempted in previous studies and in this study, we approached for the first time Also, in this study suggested new method to increase incomes fishermen such as development of suitable ranch breeding for the marine environment, ranch license(limited license), development of fisheries resources and the operation of fisheries facility. In the future, we hope to be helpful for the same field of study.

• The Korean Journal of Applied Statistics
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• v.24 no.5
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• pp.951-961
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• 2011

In this paper, we propose a Bayesian inference using the Markov Chain Monte Carlo(MCMC) method for the zero inflated negative binomial(ZINB) regression model. The proposed model allows the regression model for zero inflation probability as well as the regression model for the mean of the dependent variable. This extends the work of Jang et al. (2010) to the fully defiend ZINB regression model. In addition, we apply the proposed method to a real data example, and compare the efficiency with the zero inflated Poisson model using the DIC. Since the DIC of the ZINB is smaller than that of the ZIP, the ZINB model shows superior performance over the ZIP model in zero inflated count data with overdispersion.

• Journal of the Korea Society for Simulation
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• v.27 no.2
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• pp.71-81
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• 2018

Forklifts in a shipyard lift and transport heavy objects. Tasks occur dynamically and the rate of the task occurrence changes over time. Especially, the rate of the task occurrence is high immediately after morning and afternoon business hours. The weight of objects varies according to task characteristic, and a forklift also has the workable or allowable weight limit. In this study, we propose an online forklift dispatching algorithm based on nearest-neighbor dispatching rule using minimal cost assignment approach in order to attain the efficient operations. The proposed algorithm considers various types of forklift and multiple jobs at the same time to determine the dispatch plan. We generate dummy forklifts and dummy tasks to handle unbalance in the numbers of forklifts and tasks by taking their capacity limits and weights. In addition, a method of systematic forklift selection is also devised considering the condition of the forklift. The performance indicator is the total travel distance and the average task waiting time. We validate our approach against the priority rule-based method of the previous study by discrete-event simulation.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.4
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• pp.35-45
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• 2000

The vertex-based boundary encoding scheme is widely used in object-based video coding area and computer graphics due to its scalability with natural looking approximation. Existing single framebased vertex encoding algorithm is not efficient for temporally correlated video sequences because it does not remove temporal redundancy. In the proposed method, a vertex point is selected from not only the boundary points of the current frame but also the vertex points of the previous frame to remove temporal redundancy of shape information in video sequences. The problem of selecting optimal vertex points is modeled as finding shortest path in the directed acyclic graph with weight The boundary is approximated by a polygon which can be encoded with the smallest number of bits for maximum distortion. The temporal redundancy between two successive frames is efficiently removed with the proposed scheme, resulting in lower bit-rate than the conventional algorithms.

• Journal of Korean Society for Quality Management
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• v.44 no.2
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• pp.341-356
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• 2016

Purpose: The purpose of this paper is to study whether the adoption of Six Sigma quality management by a firm positively affects its financial performance. The correlation between the duration of Six Sigma implementation period and the financial status of the firm is investigated as well. Methods: We conduct the analysis using data from Manufacturing Industry Productivity Panel Survey 2013 provided by Korea Productivity Center and Ministry of Trade, Industry and Energy. Propensity score matching is used to reduce sample selection bias of observational study. Furthermore, we use multiple linear regression in order to study the relationship between the implementation of Six Sigma quality management and financial performance. The return on assets and ratio of net income to net sales are considered as dependent variable and implementation of Six Sigma as independent variable. Results: The indication of this analysis is that implementation of Six Sigma quality management does not significantly enhance financial status. The firms that adopted Six Sigma quality management were categorized into three groups according to the implementation period. Comparison of each group with the firms that do not adopt Six Sigma quality management does not show statistically significant enhancement of financial status. Conclusion: In conclusion, both adoption and duration of six sigma quality management do not affect financial performance significantly.

• International Commerce and Information Review
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• v.16 no.3
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• pp.307-329
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• 2014

Medical tourism involves patients intentionally leaving their home country to access non-emergency health care services abroad. Growth in the popularity of this practice has resulted in a significant amount of attention being given to it from researchers, policy-makers, and the media. Yet, there has been little effort to systematically synthesize what is known about the effects of this phenomenon and key choice factors. This study seeks to figure out, using conjoint analysis, what factors Chinese medical tourists place importance on maximizing utility when selecting their destination and propose selection attributes that can lure medical tourists to Korea. Results showed that, of destination attributes, medical technology competitiveness proved be the most important and of lower levels, international accreditation proved to have the highest utility. This article presents the findings of valuable insights to medical institutions, travel agencies and related firms in their marketing activities.