• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.523-533
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• 2006

We analyze two finite buffers queueing system with priority scheduling dependent upon queue length. Customers are classified into two types ( type-l and type-2 ) according to their characteristics. Here, the customers can be considered as traffics such as voice and data in telecommunication networks. In order to support customers with characteristics of burstiness and time-correlation between interarrival, the arrival of the type-2 customer is assumed to be an Markov- modulated Poisson process(MMPP). The service order of customers in each buffer is determined by the queue length of two buffers. Methods of embedded Markov chain and supplementary variable give us information for queue length of two buffers. Finally, performance measures such as loss and mean delay are derived.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.40
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• pp.147-167
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• 2008

This paper investigates changing business transaction under the e-commerce environment and their implications on freight transport industry with some case studies. It shows that an efficient and reliable delivery system is essential for e-commerce as business industries are faced with the stricter and more diversified demands of customer. In addition, many aspects of business practices such as small batch, customized production and just-in-time distribution in the e-commerce environment, in turn, bring about a number of changes in the volume and service patterns of freight transport. E-commerce requires longer transport distances and often higher delivery frequencies. It also entails to a certain extent a modal shift towards truck and air freight transport modes. On the one hand, the logistical requirements of e-commerce goods may stimulate greater complexity in existing supply chain management, causing higher costs. However it is true that the increased visibility of goods through more efficient information flow allows more efficient and effective transport management in the logistics system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.10b
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• pp.23-28
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• 2000

The DGPS is used to improve the accuracy of the GPS by determining the positioning error data known locatio and subsequently transmitting the determined error, or corrective factors, to users of the GPS operating in the same geographical area. The accuracy of the DGPS available to real0time users is published in the Federal Radio-Navigation Plan to be better than 10 meters, although users often experience accuracies of better than 3 meters. USA recently decided to expand the marine DGPS service for land applications and initiated the Nationwide DGPS chain. Korea is processing for improving the marine DGPS. We have not achieved Full Operational Capability. But after announcing FOC, we have to begin expansion of DGPS into land. This paper investigate the availability of marine DGPS in land. The results will provide a basic guide for estimation of a propagation loss of the marine DGPS frequency in land.

• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.1
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• pp.101-112
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• 2004

Customer satisfaction level is usually measured in terms of price, qualify, customization, after-sale-service, product variety etc. Each firm sets up a distinctive production/marketing strategy to gain competitive advantage by Prioritizing the customer satisfaction measures. The market differentiation strategy directly results in supply chain performance such as lead time, inventory, customer fill rate and market share. Product proliferation desirable in customization sense often conflicts the economies of scale effect in production side. This paper focuses the relationship between product variety and market share. Specifically, we investigate how introduction of new product affects the current market share, i.e., formation of customer preference and provide some insight into the optimal range of product variety.

• Proceedings of the Korean Society for Quality Management Conference
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• 2004.04a
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• pp.499-502
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• 2004

Multi-server Markovian retrial model with heterogeneous servers is analyzed. Arriving customers constitute the MMAP(Marked Markovian Arrival Process). Distribution of the primary customers among the servers is performed randomly depending on the type of a customer and the number of the server. Customers from the orbit have the exponential service time distribution with a parameter depending on the server only. The choice of the server for a retrial is made randomly as well. Multidimensional continuous time Markov chain describing operation of the model is investigated by means of reducing to asymptotically quasi-toeplitz Markov chaius.

• Journal of the Korean Statistical Society
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• v.4 no.1
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• pp.79-87
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• 1975

However, the mechanism for producing revised estimate is the principal means of varying the resulting precisions of estimate. Therefore, a scheduling system including physician's revision should be checked by a computer simulation to evaluate possible gains to admissions scheduling accruing from the use of these estimates. The ability to accurately predict bed occupancy has long been an objective of hospital management. If the one were able to anticipate bed accupancy, then the one could more accurately plan for bed needs, schedule personnel, allocate service and supply. We may conclude that even though the Markov chain analysis would not lead to ready-made answers for the scheduling system of elective patients, it can provide the more detailed and systematic knowledgy for the solutions on the weekly base as well as the foundations for long run planning in relative sense.

• Korean Journal of Veterinary Research
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• v.57 no.4
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• pp.245-248
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• 2017

At the time of visiting, the cat was 6-year-old female Siamese cat. The mammary mass was solid and firm and measured $2{\times}5cm^2$ in greatest diameter. The uterus revealed thick uterine horn and cross sectioned wall. Histopathologically, the mammary mass revealed feline mammary carcinoma. In the uterus, cystic endometrial hyperplasia was observed. Feline leukemia virus positive reaction was detected by polymerase chain reaction. As far as we know, this is the first report of the simultaneous feline mammary carcinoma and uterine endometrial cystic hyperplasia with Feline leukemia virus infection in a cat.

• Journal of the military operations research society of Korea
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• v.29 no.1
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• pp.43-56
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• 2003

This paper is intended to investigate the Build-up Method of SCM(Supply Chain Management) Connection applying EC Standard. SCM helps companies plan and supply to meet customer demand. SCM is the only solution available today that enables an organization to strategize, plan and execute a company's buy, make, move, store, fulfill and service business processes across multiple enterprises for total profitability. The research of modern scientists has thrown new light on the subject. However, the study of SCM for EC Standard has been strangely neglected by critics. Consequently, existing SCM systems, which require to introduce the functions of EC, need to be changed. Summarizations of the main points that have been analyzed in this paper are as follows:. the sharing information for connection and the Rosetta-net standard of the existing SCM system(Order management module(PIP 3A4) of the Rosetta-net specifications for connection by the Rosetta-net). Finally, it shows the process of the gateway for connecting among the existing SCM systems.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.5
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• pp.877-892
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• 1996

The purpose of this was to test the interactive effects of usage situation and personal characteristics on perceived risk, importance of store attributes and store-type choice. The data were collected via a questionnaire from 601 housewives of ages 20's∼ 50's living in Seoul, Korea, and analyzed by factor analysis and repeated measure two-way ANOVA. The results of this study were as follows: First, the interactive effect of age and situation on economic risk was significant. Second, the significant infraction of age and situation on importance of product price/variety was found, and there were significant intractions of education and situation on importance of service/convenience, discount policy and product information sources/promotion. Third, the interactive effects of situation and personal characteristics (age, income, education or job) on store-type choice (brand chain store, discount store, department store, designer boutique, local store or a wholesale market) were significant.

• Journal of Korea Port Economic Association
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• v.18 no.1
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• pp.85-106
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• 2002

Across many industries, benchmarking is considered useful method to improve their service quality and achieve competitive advantage. Benchmarking, especially, has emerged as an increasingly important approach to improving the performance of logistics system and enables successful logistics services and doing good business in logistics services. There are no, however, literature approach for the relationship between benchmarking and port. It is the highest worth researching the application of benchmarking method on the port, since port is the most important component in supply Chain. Therefore, this paper tries to demonstrate the application of the benchmarking method on the port. To do this study, the literature approach developed by several researchers for logistics benchmarking is used as the basic framework. In addition, the following studies are executed: First, the survey of previous studies on logistics benchmarking. Second, finding the indicator and selecting the target in the port benchmarking. Third, the systematic execution schemes of the port benchmarking. Finally, based on the above studies, this paper provides a background for discussions on the future prospects for the application of the benchmarking method on the port.