• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.81-93
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• 2012

We propose efficient mobility management schemes based on pointer forwarding for Proxy Mobile IPv6 Networks(PMIPv6) with the objective to reduce the overall network traffic incurred by mobility management and packet delivery. The proposed schemes are per-user-based, i.e., the optimal threshold of the forwarding chain length that minimizes the overall network traffic is dynamically determined for each individual mobile user, based on the user's specific mobility and service patterns. We demonstrate that there exists an optimal threshold of the forwarding chain length, given a set of parameters characterizing the specific mobility and service patterns of a mobile user. We also demonstrate that our schemes yield significantly better performance than schemes that apply a static threshold to all mobile users. A comparative analysis shows that our pointer forwarding schemes outperform routing-based mobility management protocols for PMIPv6.

• Journal of Korea Port Economic Association
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• v.28 no.2
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• pp.113-128
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• 2012

By strengthening the market control and expanding the networks, providers of global logistics are expanding their service scope. Warehouses connects networks to between internal and external warehouses worldwide by using employees. The paper focuses on analyzing the efficiency of the top forty Global Logistics Providers. Therefore, the study classifies the factors which specify the efficiency of a total logistics industry and verified its firmness. Furthermore, the most recent published reports by Logistics Quarterly and Armstrong Association in 2012 was used in order to guarantee credibility of the study. For scope period for analysis, this study utilizes three years of materials, from 2007 to 2010. By applying the DEA Window model and Malmquist, the trend in efficiency and stableness was analyzed. Consequently, the main purpose of the paper is evaluating the efficiency. Also, analyzing its determinants and illustrating a long-term relationship between the annual turnover and the number of Industry Focus/Key Customers was used as output measures. In addition, the number of warehouses worldwide and employees worldwide, of Logistics Providers were used as input measures.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.2
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• pp.683-701
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• 2012

IEEE 802.11 standard has achieved huge success in the past decade and is still under development to provide higher physical data rate and better quality of service (QoS). An important problem for the development and optimization of IEEE 802.11 networks is the modeling of the MAC layer channel access protocol. Although there are already many theoretic analysis for the 802.11 MAC protocol in the literature, most of the models focus on the saturated traffic and assume infinite buffer at the MAC layer. In this paper we develop a unified analytical model for IEEE 802.11 MAC protocol in ad hoc networks. The impacts of channel access parameters, traffic rate and buffer size at the MAC layer are modeled with the assistance of a generalized Markov chain and an M/G/1/K queue model. The performance of throughput, packet delivery delay and dropping probability can be achieved. Extensive simulations show the analytical model is highly accurate. From the analytical model it is shown that for practical buffer configuration (e.g. buffer size larger than one), we can maximize the total throughput and reduce the packet blocking probability (due to limited buffer size) and the average queuing delay to zero by effectively controlling the offered load. The average MAC layer service delay as well as its standard deviation, is also much lower than that in saturated conditions and has an upper bound. It is also observed that the optimal load is very close to the maximum achievable throughput regardless of the number of stations or buffer size. Moreover, the model is scalable for performance analysis of 802.11e in unsaturated conditions and 802.11 ad hoc networks with heterogenous traffic flows.

• Korean Journal of Veterinary Service
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• v.24 no.1
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• pp.83-88
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• 2001

It is impotent to identify the causative agents of abortion in equine for minimizing the loss of breeding costs in equine Industry. Recently, the abortion has often occurred in equine herds and thus the purpose of the study was aimed at the identification of equine herpesvirus-1, one of the frequent pathogens to abortion, using polymerase chain reaction. Six fetuses to be aborted at nine to ten months in pregnancy reared in six herds were used in the study. Two primers in the PCR were made from glycoprotein B gene of EHV-1. The primers specific for EHV-1 amplified 1880 bp of PCR products from DNA extracts from thorax fluids, livers, lungs, and spleens of four in six aborted fetuses. Consequently, PCR could be applied to diagnose the abortion of EHV-1 and also confirmed to play a major role of the viral pathogen associated with equine abortion in Jeju island.

• Korean Journal of Veterinary Service
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• v.37 no.3
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• pp.219-224
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• 2014

A eight-month-old blue and yellow macaw (Ara ararauna) with psittacine beak and feather disease (PBFD)-suspected signs, such as, abnormal feather, depression and diarrhea, was presented to Animal Disease Intervention Center, Kyungpook National University in 16 April 2014. The partial ORF V1 gene of PBFD virus (PBFDV) was detected by polymerase chain reaction (PCR) from DNA templates extracted from feather, blood and cloacal swab sample of the bird, but no other viral DNAs that often infected in psittacine birds including avian bornavirus and avian polyomavirus were detected from the samples of the bird, indicating this case is due to single infection of PBFDV. Nucleotide sequence analysis of the amplified partial ORF V1 gene was confirmed to have 96.7% and 93.6% homology with that of previously reported PBFDV strain (Genbank no. HM748924 and FJ685980). This report describes the first detection of PBFDV in PBFD-suspected blue and yellow macaw in Korea.

• Korean Journal of Veterinary Service
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• v.41 no.2
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• pp.111-118
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• 2018

This study was carried out to investigate the prevalence of honeybee (Apis mellifera) diseases in Gwangju area. From November 2016 to August 2017, 89 samples were collected from 33 apiculture farms and reverse transcriptase-polymerase chain reaction (RT-PCR), polymerase chain reaction (PCR), and real time PCR were conducted. 14 infectious pathogens, including seven viruses, two bacteria, three fungi, and two parasites, were investigated from random apiculture farms in Gwangju. The percentage of infectious pathogens were as follows: Stonebrood (76.4%), Deformed wing virus (51.7%), Nosema (27.0%) in PCR and RT-PCR. This result indicated that Stonebrood was most prevalent disease in Gwangju area. And we could get similar results from real time PCR. 84.8% of farms have more than two of infectious pathogens. Stonebrood and Deformed wing virus were major diseases in almost all seasons and Black queen cell virus disease was especially prevalent in May.

• Journal of the Korean Operations Research and Management Science Society
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• v.31 no.1
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• pp.91-103
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• 2006

Given a bill of materials (BOM) tree T labeled by the breadth first search (BFS) order from node 0 to node n and a general network ${\Im}=(V,A)$, where V={1,2,...,m} is the set of production facilities and A is the set of arcs representing transportation links between any of two facilities, we assume that each node of T stands for not only a component. but also a production stage which is a possible stocking point and operates under a periodic review base-stock policy, We also assume that the random demand which can be achieved by a suitable service level only occurs at the root node 0 of T and has a normal distribution $N({\mu},{\sigma}^2)$. Then our integrated model of facility location problems and safety stock optimization problem (FLP&SSOP) is to identify both the facility locations at which partitioned subtrees of T are produced and the optimal assignment of safety stocks so that the sum of production cost, inventory holding cost, and transportation cost is minimized while meeting the pre-specified service level for the final product. In this paper, we first formulate (FLP&SSOP) as a nonlinear integer programming model and show that it can be reformulated as a 0-1 linear integer programming model with an exponential number of decision variables. We then show that the linear programming relaxation of the reformulated model has an integrality property which guarantees that it can be optimally solved by a column generation method.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.265-271
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• 2011

Lymphoma is the most common hematopoietic malignancy in dogs. Diagnosis of lymphoma is classically performed by morphological assessment and immunohistochemistry. But some cases in the early stage are difficult to distinguish and need more objective and accurate methods. So, Polymerase chain reaction (PCR) for antigen receptor rearrangements (PARR) and flow cytometric immunophenotype of lymphoma have been developed continuously. In this study, we performed these two methods to classify lymphoma type in 3 cases. According to PARR analysis, B cell origin lymphoma was diagnosed in two of three cases by testing PBMC and lymph node. All fine needle aspiration (FNA) samples of lymph nodes had high expression of CD21 on >88% of total cell population and PBMC samples also showed high expression of CD21 on >30% of total lymphocytes in those two cases, while the expression of CD3, CD4 and CD8 was absent. These results suggest that concurrent use of PARR and flow cytometric immunophenotype is more effective and valuable tool for the diagnosis and monitoring of canine lymphoma patients.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.15-20
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• 2020

A manufacturing industry has secured its competitiveness through cost reduction, research for new products, development of manufacturing technology traditionally. However, many manufacturers are being required of innovative efforts for business sustainability by emergence of new technology and industry owing to fast technology development and convergence among technologies and industries. Continuous growth can not be expected with the way of simple manufacturing and sales under the 4^th industrial revolution era. Separation of service from product is getting more vague in some specific area and a service provider is often offering its own product together. Innovation destroying manufacturing value chain with servitization can only create the new value. Basic concept of servitization, paradigm change and future prospect of manufacturing industries suffering from the 4^th industrial revolution will be analyzed in this paper. Also, the strategy, application and methodology for servitization required in the convergence period will be researched.

• The Research Journal of the Costume Culture
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• v.12 no.4
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• pp.547-565
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• 2004

The purpose of this study was to evaluate the level of SCM activities and the logistics performance by SCM of the three company types in fashion industry· fabric suppliers, apparel manufacturers, and retailers. The level of SCM activities was estimated through the examination of seven factors: commitment and leadership of a top management, flexibility of management, understanding of demand characteristics, integrated management organization, information system, cooperative partnership and communication and exchange of opinion. The logistics performance was measured by improvement in customer service(on time delivery ratio of products, returning rate, treat ratio for A/S, order fill rate, substitute providing capability for being out of stock) and delivery cost reduction. Through questionnaire survey, a total of 214 data for 108 companies of three company types were collected: 46 for 40 fabric suppliers, 123 for 64 apparel manufacturers and 45 for 4 retailers. The analysis of SCM activity levels showed that fabric suppliers had higher degrees in the factor of understanding of demand characteristics, and apparel manufacturers had higher degrees in the factor of information systems. For retailers, the factor of communication and exchange of opinion represented higher degrees. The study on relationship between the SCM activity levels and logistics performance showed that the SCM activity factor of understanding of demand characteristics greatly improved a substitute providing capability for being out of stock in fabric suppliers, and information system improved a substitute providing capability for being out of stock, on time delivery ratio of products and order fill rate in apparel manufacturers. In retailers, the SCM activity factor of understanding of demand characteristics decreased returning rate highly and improved on time delivery ratio of products. The study results showed that SCM activities in fashion industry brought more improvement in customer service levels rather than in delivery cost reduction.