• IE interfaces
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• v.13 no.3
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• pp.424-430
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• 2000

Supply chain management (SCM) is an area that has recently received a great deal of attention in the business community. While SCM is relatively new, the idea of coordinated planning is not. During the last decades, many researchers have investigated multi-stage inventory problems. However, only a few papers address the problem of cost-optimal coordination of multi-stage inventory control with respect to service measures. Even published approaches have a shortcoming in dealing with a delivery lead time consisted of a shipping time and a waiting time. Assumed that there is no waiting time, or that the delivery lead time is implicitly compounded of a shipping time and a waiting time, the problem is often simplified into a multi-stage buffer allocation and a single-stage stochastic buffer sizing problem at all installations. This paper presents a simulation-based heuristic algorithm and a comparison with others for the problem that cannot be decomposed into a multi-stage buffer allocation and a single-stage stochastic buffer sizing problem because the waiting time ties together all stages. The comparison shows that the simulation-based heuristic algorithm performs better than other approaches in saving average inventory cost for both Poisson and Normal demands.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.9
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• pp.823-834
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• 2008

Recently, interests for SRM have been increasing rapidly to automate the whole processes of supply chain from sourcing to procurement and improve the whole efficiency of supply chain by strategically managing the relationship with external partners (suppliers). The national procurement service of Korea is trying to build new paradigms by introducing SRM for improving the competitiveness of national public procurement service. For this, a new assessment model for evaluating and selecting suppliers with fairness and objectivity should be developed. In this paper, we propose a new SRM solution including a model that evaluates and grades of suppliers' capabilities of performing the contracts. We also explain the innovation of national public procurement system through this SRM solution.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3446-3464
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• 2017

Backoff mechanism serves as one of the key technologies in the MAC-layer of wireless mobile networks. The traditional Binary Exponential Backoff (BEB) mechanism in IEEE 802.11 Distributed Coordination Function (DCF) and other existing backoff mechanisms poses several performance issues. For instance, the Contention Window (CW) oscillations occur frequently; a low delay QoS guarantee cannot be provided for real-time transmission, and services with different priorities are not differentiated. For these problems, we present a novel Multi-Priority service differentiated and Adaptive Backoff (MPAB) algorithm over IEEE 802.11 DCF for wireless mobile networks in this paper. In this algorithm, the backoff stage is chosen adaptively according to the channel status and traffic priority, and the forwarding and receding transition probability between the adjacent backoff stages for different priority traffic can be controlled and adjusted for demands at any time. We further employ the 2-dimensional Markov chain model to analyze the algorithm, and derive the analytical expressions of the saturation throughput and average medium access delay. Both the accuracy of the expressions and the algorithm performance are verified through simulations. The results show that the performance of the MPAB algorithm can offer a higher throughput and lower delay than the BEB algorithm.

• Korean Journal of Veterinary Service
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• v.40 no.3
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• pp.161-168
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• 2017

Caprine arthritis encephalitis (CAE) virus is a causative agent of caprine arthritis-encephalitis. In our previous study we reported a prevalence of CAE. In this study, we described the further detailed pathological features of CAE and examined the detection of virus by in situ hybridization (ISH). Histopathologically, interstitial pneumonia and bronchopneumonia in lung, focal inflammation in mammary glands, perivascular cuffing in brain, arthritis, and focal necrosis, mild steatosis, inflammatory cell infiltration of liver were noted. CAEV proviral-DNA was identified by nested polymerase chain reaction (PCR) in blood cells, brain, synovial fluid, and lymph node. Confirmation by nested PCR involved amplification of a 296 bp ($1^{st}$ PCR) and 185 bp ($2^{nd}$ PCR) fragments corresponding to a conserved region on the gag gene of CAEV. Positive ISH signals were detected in the brain and liver. In conclusion, significant histopathological findings included parenchymal infection in various organs, including the lung, liver, brain, joint, and mammary gland were noted in the CAEV infected dairy goat. ISH can help confirm the diagnosis of CAE in formalin-fixed samples.

• Korean Journal of Veterinary Service
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• v.41 no.2
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• pp.105-110
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• 2018

A total of 41 Salmonella (S.) strains were isolated from pigs suffered with severe watery diarrhea and were tried to identify by both matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and polymerase chain reaction (PCR) analysis. Fibrinous exudate and ulceration in the large intestine were prevalent in gross observation, and variable degrees of enteritis were observed in the histology of large intestines. Subsequent polymerase chain reaction (PCR) analyses demonstrated that 41 strains were identified as S. Typhimurium (39 strains), though 2 stains were failed to identify. Further identification was performed using both direct smear and protein extraction method by MALDI-TOF MS analyses. In terms of extraction methods, 100% (41/41) of isolates were identified to species level of S. spp. Whereas only 43.9% (18/41) were identified to species level using the direct method. These results thus suggest that rapid and accurate diagnosis of porcine salmonellosis can be guaranteed by MALDI-TOF MS combined with protein extraction method.

• Proceedings of the Safety Management and Science Conference
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• 2011.11a
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• pp.499-506
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• 2011

새로운 IT 환경에서의 변화를 이해하고 경쟁력 있는 클라우드 생태계를 구축하며, 지속가능한 성장을 위한 경쟁정책을 수립하기 위해서는 먼저 우리나라 IT시장의 구조와 그 변화를 정확히 이해하는 것이 필요하다. IT시장의 구조를 이해하기 위한 과거의 선행연구들은 통신시장을 배경으로 수직적 가치사슬 구조를 중심으로 설명한 것이 대부분이었으나, 최근 들어 이슈로 부각하고 있는 클라우드 생태계에 관한 연구는 부족한 실정이다. 본 연구의 목적은 IT시장에서의 클라우드 서비스의 등장에 따른 가치사슬의 변화를 이해하는 것이다. 이를 위해 먼저 기존의 연구 문헌들을 통하여 기업 또는 산업의 공급 구조, 그리고 시장의 생태계를 설명하기 위해 사용하는 기본 틀인 가치사슬의 개념을 정의하고, 이를 통하여 우리나라 IT시장의 가치사슬에 대해, 특히 클라우드 서비스 도입이후의 우리나라 IT시장의 변화를 반영하여 그 구조의 변화를 설명하며, 이를 바탕으로 우리나라 IT시장을 진단하고 시장의 성장을 견인하는 요인들을 파악하도록 한다. 본 연구를 통해 가치사슬 관점에서 IT시장을 이해함으로써, 클라우드 서비스 산업의 경쟁력을 높이고, 향후 클라우드 기반으로 IT생태계를 구축하기 위한 이론적 근거로 활용되길 기대한다.

• Korean Journal of Veterinary Service
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• v.37 no.1
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• pp.29-33
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• 2014

This study aimed at finding a fast, sensitive, and efficient protocol for molecular identification of intracellular protozoa Toxoplasma (T.) gondii. For molecular detection of T. gondii, we developed a polymerase chain reaction coupled with dot blot hybridization assay (PCR/DBH). For DBH analysis, the amplified DNA of T. gondii tachyzoite was labeled by incorporation of digoxigenin. The DBH assay alone was capable of detecting down to $1{\times}10^4$ pg of T. gondii genomic DNA. The PCR alone was capable of detecting down to $1{\times}10^3$ pg of T. gondii genomic DNA, whereas the PCR/DBH assay was capable of detecting down to $1{\times}10^2$ pg of T. gondii genomic DNA, indicating that sensitivity of the PCR/DBH method was approximately 10 to 100 times higher than PCR or DBH alone. Our PCR/DBH assay will be useful for confirming the presence of T. gondii on the samples and differentiating T. gondii infection from other intracellular protozoa infections.

• Korean Journal of Veterinary Service
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• v.36 no.2
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• pp.147-150
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• 2013

This study was carried out to investigate the prevalence of honeybee (Apis mellifera) disease in cheonan and asan area. From September to November in 2012, 33 samples were collected from 33 apiculture farms in the regions and reverse transcriptase-polymerase chain reaction (RT-PCR) and polymerase chain reaction (PCR) was conducted. Among 33 samples, prevalence rate was 42% in Sac Brood Virus (SBV), 52% in Nosema, 21% in American foulbrood (AFB), 70% in European foulbrood (EFB), 97% in Stonebrood, 3% in Chalkbrood. The result indicate that stonebrood was most prevalent disease in apiculture farms in cheonan and asan area.

• Korean Journal of Veterinary Service
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• v.32 no.1
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• pp.43-48
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• 2009

Salmonella enterica serovar Gallinarum is the causative agent of fowl typhoid (FT) and Salmonella enterica serovar Pullorum is pullorum disease (PD), a severe systemic disease of chick and it has the same antigenic fomula, the close relation but distinct pathogen. The traditional bacteriologic and serologic methods routinely used but tedious, time consuming. some of biochemical differences are helpful in differentiating the two organisms, however variation in the characteristics of some strains can be observed. During 2006 to 2008, there was isolated 30 strains. The biochemical characteristics of S. Gallinarum was nonmotile, fermentation of dulcitol, maltose but positive arginine (6.6%), lysine (83.3%) and arabinose (20.0%). The antimicrobial susceptibility test showed 100% sensitive to amikacin, ampicillin, amoxicillin/clavulanic acid and florfenicol, but resistant to penicillin (100%) and erythromycin (60.0%). This PCR method can be applied in the diagnosis between S. Gallinarum and S. Pullorum.

• East Asian Journal of Business Economics (EAJBE)
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• v.12 no.3
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• pp.1-10
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• 2024

Purpose: In the context of fresh food e-commerce, this study investigates the intermediary mechanisms between last-mile logistics service quality (LMLSQ) and customer loyalty. Utilizing the Quality-Value-Loyalty chain as a framework, it focuses on how perceived functional and emotional value mediate this relationship. Research design, data and methodology: Data was gathered through questionnaires from Chinese customers who purchased fresh products from fresh food e-commerce platforms which provide self-delivery services. Partial least squares structural equation modeling (PLS-SEM) was used to examine the proposed hypotheses after confirmatory factor analysis (CFA) revealed the validity and reliability of the data. Results: The findings reveal that condition quality and personnel contact quality positively influence both functional and emotional value, which, in turn, significantly impact customer loyalty. Timeliness quality, however, does not significantly affect functional or emotional value, indicating its limited impact on customer loyalty. Conclusions: The study confirms that improving condition quality and personnel contact quality significantly boosts customer loyalty by enhancing perceived functional and emotional value. The findings highlight the importance for fresh food e-commerce platforms to offer high-quality, reliable, and emotionally satisfying LMLSQ. The results offer practical insights for e-commerce platforms to focus on specific service quality dimensions to foster customer loyalty and contribute to the theoretical understanding of the quality-value-loyalty framework.