• 한국통신학회논문지
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• 제34권6B호
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• pp.605-614
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• 2009

기존의 인터넷 서비스는 대부분 데이터 전송과 같은 최선형 서비스로 지원 되었고 전송 지연 및 패킷 손실이 허용되었지만 최근 인터넷 전화, 인터넷 방송등과 같은 인터넷 멀티미디어 서비스들은 실시간 처리 및 높은 대역폭을 요구하고 있다. 이를 위해 IETF (Internet Engineering Task Force)에서도 인터넷 상에서 TP QoS를 제공하기 위한 연구가 활발히 이루어지고 있는데 그 중 버퍼 관리 메커니즘으로RED(Random Early Detection) 알고리즘과 같은 능동적인 버퍼 관리 기법을 제시하였다. 그러나 이는 평균 버퍼 길이를 이용한 한계와 불공정성 등에 대한 문제를 가지고 있고 이러한 문제를 해결하기 위한 RED를 변형한 여러 가지 방법들이 제시되고 있으나 다양한 인터넷 사용자 QoS 요구 사항을 충족시키는데 어려움이 있다. 이에 따라, 본 논문에서는 사용자들의 다양한 QoS를 요구하는 인터넷 멀티미디어 서비스를 지원하기 위한 QoS 적응형 AQM (active Queue Management) 알고리즘을 제안하고 ns-2를 이용한 시뮬레이션을 통해 성능 분석을 제시하였다.

• 한국시뮬레이션학회논문지
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• 제14권3호
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• pp.119-127
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• 2005

Web services and their composition (web processes) are promising technologies to efficiently integrate disparate software components over various types of systems. As many web services are nowadays available on Internet, quality of services (QoS) and performance/cost become increasingly important to differentiating between similar service providers. In this work, we introduce sPAC (Web Services Performance Analysis Centre) and show how customers can benefit from sPAC to consider performance in composing and commercializing web services. sPAC 1) helps users to graphically describe the workflow of web services, 2) invokes web services to test out performance for light load conditions, 3) automatically converts the web services and the flow between them into a simulation model, 4) conducts extensive simulations for heavy load conditions and various usage patterns, and 5) reports analysis results and estimation data for the web services.

• 유통과학연구
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• 제13권2호
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• pp.85-94
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• 2015

Purpose - This study attempts to examine the impacts of consumers' perceived service convenience of retailers on various service performance metrics such as service quality and customer satisfaction. It also tries to investigate differences in the importance of service convenience dimensions on service performance between a department store and a general super market. Research design, data, and methodology - The four hypotheses in this study were proposed and tested. Two hypotheses were on the causal relationships between service convenience dimensions and service performances (service quality and customer satisfaction). The other two hypotheses were on comparisons for the effects of convenience dimensions on service quality and customer satisfaction between department stores and general super markets. To test the hypotheses, three department store chains (Hyundai, Lotte, and Shinsegae department Store) and three general super markets (E-mart, Homeplus, and Lotte mart) were involved. Overall, 510 usable responses were used. The data were analyzed using regression analysis. Results - The results largely support the hypothesized relationships of the proposed model. The results show that access convenience, transaction convenience, benefit convenience, and post-benefit convenience have positive influences on service quality, whereas decision convenience, access convenience, transaction convenience, benefit convenience, and post-benefit convenience have positive effects on customer satisfaction. Furthermore, the results show that there are differences between department stores and general super markets in the effects of benefit convenience and post-benefit convenience on service quality as well as the effects of transaction convenience and post-benefit convenience on customer satisfaction. Conclusions - The concept of service convenience is important in retail environments but little is known about this topic in retail literature. Specially, while service convenience dimensions have different impacts on service performance in distinct retail environments, there has been little investigation or comparison between retail types as regards service convenience. This study is the first to test the differences between distinct retail types (department stores and general super markets) on the service convenience-service performance links. Managerially, the findings of this study suggest that the service convenience management of retailers is an important part of successful service performance management. Because it is most important that both department stores and general super markets enhance benefit convenience to improve service performance, managers of both store types need to invest their resources to reduce consumers' perceived time and effort expenditures to experience the retailer's core benefits. Therefore, the results of this study suggest that retail stores should spend human and financial resources to enhance customer perceptions of service convenience, while also considering what constitutes the service outcome in the consumer's mind. Furthermore, the findings suggest that managers need to use different service convenience management tactics in department stores and general super markets. Specifically, managers in general super markets should pay more attention to benefit convenience and transaction convenience to achieve better service performance whereas managers in department stores should concentrate on post-benefit convenience to create customers' positive evaluation.

• 한국동물위생학회지
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• 제20권3호
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• pp.281-288
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• 1997

Streptococcus suis has been identified as a major cause of contagious disease in pigs Ithas been isolated worldwide from pigs suffering from meningitis, bronchopneumonia, polyserositis, polyarthritis and septicemia. Two hundred and fifty-five lung samples of slaughter pigs with gross lung lesions were collected from Jan. to Dec. 1995 in southern Chonnam area. Isolation of S suis were tested by biochemical, serological methods and antimicrobial susceptibility. The results were summerrized as follows ; 1. S suis was Isolated from 30 of 254 pneumonic lungs, 14 Isolates were isolated only, 12 were isolated with p. multocida and 4 were isolated with unidentified Gram positive cocci. 2. In biochemical characteristics studies, all isolates were not grown in 6.5% NaCl medium, and most isolates utilized L-leucine-2-naphtylamide and trehalose, didn't utilize sorbitol, ribose and L-arabinose. 3. In slide agglutination test, 6(20%) Isolates were classified as serotype 2, 4(13.3%) isolates were as serotype l/2, 16, 2 and 2(6.6%) were as serotype 1, 4, 13. 4. S suis isolates showed marked susceptibility to amoxicillin, oxacillin, cephalothin and cepoferazone and high resistance to kanamycin, streptomycin, tetracycline and erythromycin.

• International journal of advanced smart convergence
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• 제3권2호
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• pp.18-21
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• 2014

A control application requirements currently used is very low, such as packet loss rate, minimum delay on sensor networks with quality of service (QoS) requirements some packet delivery guarantee. This paper is the sampling period at the end of the actuator and sensor data transfer related to the Miss ratio for each source sensor node, use the controller and the internal ANFIS. The proposed scheme has the advantages of simplicity, scalability, and General. Simulation results of the proposed scheme can provide QoS support in WSANs.

• 대한족부족관절학회지
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• 제18권2호
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• pp.80-82
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• 2014

Occurrence of pseudoaneurysm in the foot and ankle is rare, and is usually caused by traumatic injury or by iatrogenic intervention. Iatrogenic pseudoaneurysms in the foot and ankle have been observed after rearfoot and ankle fusions, ankle arthroscopy, endoscopic and open plantar fasciotomy, tibial osteotomy with limb lengthening, midfoot amputation, and Lapidus procedure. We report on a patient who developed a pseudoaneurysm of the dorsal metatarsal artery following correction of hallux valgus. The patient underwent proximal chevron osteotomy and Akin phalangeal osteotomy. The feeding artery was ligated and the pseudoaneurysm was excised.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.315-321
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• 2009

Since the KTX start its service on April 1st of 2004, KTX increased its share up to 17.4% (2008). It's the 2nd after the passenger car share of 59.2% in the national transportation, but the gap is still wide. In addition, because of the rise of goods' and oil price, the share of intercity express bus is growing up. Nevertheless Korail is trying to improve the train schedule and develop internodal transit system, the number of passengers of KTX is remain flat. KORAIL should start and proceed the tasks below. - Analysis of the 5 year's operation of KTX since the year of 2004 to make plans for the steady growth - development of the KTX operation plan for expansion of railway - preparing the operation of additional passenger rail services on the mail line for newly introduced trains. - expansion of KTX's service area after the introduction of KTX-II - introduction of other new trains - examination for the action plans to promote marketing in main-line including refinement of the rate structure

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.160-170
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• 2016

The increasing spread of antibiotic-resistant pathogens has raised the interest in alternative antimicrobial treatments. In our study, the functionally active gram-negative bacterium bacteriophage CP933 endolysin was produced in Nicotiana benthamiana plants by a combination of transient expression and vacuole targeting strategies, and its antimicrobial activity was investigated. Expression of the cp933 gene in E. coli led to growth inhibition and lysis of the host cells or production of trace amounts of CP933. Cytoplasmic expression of the cp933 gene in plants using Potato virus X-based transient expression vectors (pP2C2S and pGR107) resulted in death of the apical portion of experimental plants. To protect plants against the toxic effects of the CP933 protein, the cp933 coding region was fused at its Nterminus to an N-terminal signal peptide from the potato proteinase inhibitor I to direct CP933 to the delta-type vacuoles. Plants producing the CP933 fusion protein did not exhibit the severe toxic effects seen with the unfused protein and the level of expression was 0.16 mg/g of plant tissue. Antimicrobial assays revealed that, in contrast to gram-negative bacterium E. coli (BL21(DE3)), the gram-positive plant pathogenic bacterium Clavibacter michiganensis was more susceptible to the plant-produced CP933, showing 18% growth inhibition. The results of our experiments demonstrate that the combination of transient expression and protein targeting to the delta vacuoles is a promising approach to produce functionally active proteins that exhibit toxicity when expressed in plant cells.

• 정보처리학회논문지C
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• 제9C권2호
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• pp.277-282
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• 2002

일반적으로 유선 및 무선 ATM망에서 서비스 품질(QoS)에 대한 요구 사항은 서비스 유형에 따라 다르며, 실시간 비디오 서비스는 셀 손실보다 셀 전송 지연에 더 민감하다. 셀 손실 방지를 강조하고 있는 기존 핸드오프 방안들은 QoS를 만족시키기 위해 셀 전송 지연이 큰 단점을 가지고 있었다. 본 논문에서는 실시간 VBR 서비스에서 핸드오프 동안 새로운 기지국으로 전달될 셀 들 중에서 ATM 셀 헤더의 셀손실 우선순위(CLP)가 낮은 셀은 전달하고 CLP가 높은 셀은 폐기함으로써 셀 전송 지연을 최소화하는 방안을 제안한다. 제안된 방안은 MPEG 비디오 프레임을 대상으로 시뮬레이션을 통해 실시간 VBR 서비스의 QoS를 만족시키고 신속한 핸드오프에 적절하다는 것을 보여 주었다.

• Asia pacific journal of information systems
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• 제18권1호
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• pp.145-162
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• 2008

One of the big concerns in e-society is privacy issue. In special, in developing robust ubiquitous smart space and corresponding services, user profile and preference are collected by the service providers. Privacy issue would be more critical in context-aware services simply because most of the context data themselves are private information: user's current location, current schedule, friends nearby and even her/his health data. To realize the potential of ubiquitous smart space, the systems embedded in the space should corporate personal privacy preferences. When the users invoke a set of services, they are asked to allow the service providers or smart space to make use of personal information which is related to privacy concerns. For this reason, the users unhappily provide the personal information or even deny to get served. On the other side, service provider needs personal information as rich as possible with minimal personal information to discern royal and trustworthy customers and those who are not. It would be desirable to enlarge the allowable personal information complying with the service provider's request, whereas minimizing service provider's requiring personal information which is not allowed to be submitted and user's submitting information which is of no value to the service provider. In special, if any personal information required by the service provider is not allowed, service will not be provided to the user. P3P (Platform for Privacy Preferences) has been regarded as one of the promising alternatives to preserve the personal information in the course of electronic transactions. However, P3P mainly focuses on preserving the buyers' personal information. From time to time, the service provider's business data should be protected from the unintended usage from the buyers. Moreover, even though the user's privacy preference could depend on the context happened to the user, legacy P3P does not handle the contextual change of privacy preferences. Hence, the purpose of this paper is to propose a mutual P3P-based negotiation mechanism. To do so, service provider's privacy concern is considered as well as the users'. User's privacy policy on the service provider's information also should be informed to the service providers before the service begins. Second, privacy policy is contextually designed according to the user's current context because the nomadic user's privacy concern structure may be altered contextually. Hence, the methodology includes mutual privacy policy and personalization. Overall framework of the mechanism and new code of ethics is described in section 2. Pervasive platform for mutual P3P considers user type and context field, which involves current activity, location, social context, objects nearby and physical environments. Our mutual P3P includes the privacy preference not only for the buyers but also the sellers, that is, service providers. Negotiation methodology for mutual P3P is proposed in section 3. Based on the fact that privacy concern occurs when there are needs for information access and at the same time those for information hiding. Our mechanism was implemented based on an actual shopping mall to increase the feasibility of the idea proposed in this paper. A shopping service is assumed as a context-aware service, and data groups for the service are enumerated. The privacy policy for each data group is represented as APPEL format. To examine the performance of the example service, in section 4, simulation approach is adopted in this paper. For the simulation, five data elements are considered: $\cdot$ UserID $\cdot$ User preference $\cdot$ Phone number $\cdot$ Home address $\cdot$ Product information $\cdot$ Service profile. For the negotiation, reputation is selected as a strategic value. Then the following cases are compared: $\cdot$ Legacy P3P is considered $\cdot$ Mutual P3P is considered without strategic value $\cdot$ Mutual P3P is considered with strategic value. The simulation results show that mutual P3P outperforms legacy P3P. Moreover, we could conclude that when mutual P3P is considered with strategic value, performance was better than that of mutual P3P is considered without strategic value in terms of service safety.