• 제목/요약/키워드: combined service

검색결과 831건 처리시간 0.03초

소프트웨어 정의 네트워크상의 미들박스 성능을 고려한 동적 서비스 체이닝 방안 (Dynamic Service Chaining Method Considering Performance of Middlebox Over SDN)

  • 오현석;김남기;최윤호
    • 인터넷정보학회논문지
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    • 제16권6호
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    • pp.47-55
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    • 2015
  • 기존 동적 라우팅은 최소 링크 비용을 기준으로 최적의 라우팅 경로를 설정하고 이에 따라 유입 혹은 유출 되는 플로우를 단말로 전송한다. 하지만 이 경우에는 보안 기능을 담당하는 미들 박스를 우회하게 되고 이에 따라 해당 네트워크는 보안 위협을 직면하게 되는 문제가 발생한다. 따라서 최적의 라우팅 경로 설정 시 각 플로우의 서비스 유형을 고려하여 해당 플로우를 보안 미들 박스를 거쳐 단말로 전송하기 위한 라우팅 방안인 동적 서비스 체이닝이 필요하다. 본 논문에서는 SDN의 동적 플로우 트래픽 제어 기능과 보안 서비스 기능을 동시에 고려한 동적 라우팅 방안에 대해 제안한다.

모바일 환경에서 문제은행에 기반한 학습 시스템의 개발 (Development of an Item Based Learning System In Mobile Environment)

  • 장무수;송희헌;강오한
    • 한국산업정보학회논문지
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    • 제9권3호
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    • pp.46-54
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    • 2004
  • 현대사회에서 휴대전화의 보급이 확산되면서 휴대전화와 인터넷이 결합된 무선 인터넷의 모바일이라는 서비스가 나타나게 되었다. 모바일 서비스의 시작과 더불어 모바일 컨텐츠의 개발도 활발하게 이루어지고 있어 기존의 유선 인터넷 환경에서 이루어지던 서비스들이 점차 무선 인터넷 환경의 모바일로 이동되고 있다. 그러나 모바일 환경에서 서비스되고 있는 컨텐츠들은 벨소리, 게임 등 엔터테인먼트 분야가 대부분이며 학습을 위한 컨텐츠는 매우 부족한 상태이다. 본 논문에서는 학습자들이 한정된 자리에서 벗어나 모바일 기기를 이용하여 언제 어디서나 문제은행 학습 컨텐츠에 접속하여 효율적으로 학습할 수 있는 모바일 학습 컨텐츠를 개발하였다.

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교육정보 통합 플랫폼 구현을 위한 통합 사용자 인증 서비스의 설계 및 구현 (The Design and Implementation of Single Sign-On Service for Education-related Information Service Platform)

  • 박정호
    • 한국산학기술학회논문지
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    • 제12권1호
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    • pp.100-109
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    • 2011
  • 본 논문은 개별적으로 사용자 인증 시스템이 구현된 16개 시 도교육청 교육정보서비스와 한국교육학술정보원의 교육정보서비스를 단일 사용자 인증을 통해 모두 이용할 수 있는 최적의 방안을 연구하여 도출한 것이다. 본 논문에서는 도출된 방안에 따라 통합 사용자 인증 서비스를 제공할 수 있는 시스템을 설계하고 구현함으로써 16개 시 도교육청과 한국교육학술정보원이 공동으로 운영 중인 전국교육정보공유체제의 교육정보 서비스 이용에 편리성을 도모하는 동시에 사용자 인증 관리의 효율과 안전을 기할 수 있는 방안을 마련하였다.

Numerical study of concrete-encased CFST under preload followed by sustained service load

  • Li, Gen;Hou, Chao;Han, Lin-Hai;Shen, Luming
    • Steel and Composite Structures
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    • 제35권1호
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    • pp.93-109
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    • 2020
  • Developed from conventional concrete filled steel tubular (CFST) members, concrete-encased CFST has attracted growing attention in building and bridge practices. In actual construction, the inner CFST is erected prior to the casting of the outer reinforced concrete part to support the construction preload, after which the whole composite member is under sustained service load. The complex loading sequence leads to highly nonlinear material interaction and consequently complicated structural performance. This paper studies the full-range behaviour of concrete-encased CFST columns with initial preload on inner CFST followed by sustained service load over the whole composite section. Validated against the reported data obtained from specifically designed tests, a finite element analysis model is developed to investigate the detailed structural behaviour in terms of ultimate strength, load distribution, material interaction and strain development. Parametric analysis is then carried out to evaluate the impact of significant factors on the structural behaviour of the composite columns. Finally, a simplified design method for estimating the sectional capacity of concrete-encased CFST is proposed, with the combined influences of construction preload and sustained service load being taken into account. The feasibility of the developed method is validated against both the test data and the simulation results.

장르유사도와 선호장르를 이용한 협업필터링 설계 (Collaborative Filtering Design Using Genre Similarity and Preffered Genre)

  • 김경록;변재희;문남미
    • 한국컴퓨터정보학회논문지
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    • 제16권4호
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    • pp.159-168
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    • 2011
  • 전자상거래와 소셜미디어 서비스의 활성화에 따라, 집단지성을 개인 맞춤 서비스에 활용하는 추천시스템에 관한 연구가 활발히 진행되고 있다. 또한, 스마트폰의 발달과 모바일 환경의 발달에 따라 단말의 제약성에도 불구하고 개인화 서비스에 대한 연구가 가속화되고 있다. 대표적인 예로 위치기반 서비스와의 결합이다. 이에 본 연구에서는 영화의 장르유사도와 선호장르를 이용한 추천시스템을 제안한다. 영화 장르 유사도 프로파일을 생성하여 이를 모바일실험 환경에서 서비스 될 수 있도록 설계하고 프로토 타이핑 한 후에 MovieLens 데이터를 적용하여 평가한다.

Serological characterization of bovine viral diarrhea virus isolates

  • Chung, Chung-won;Cho, In-soo;Cho, Jae-jin;Son, Yeon-seong;An, Soo-hwan
    • 대한수의학회지
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    • 제39권4호
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    • pp.743-750
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    • 1999
  • Bovine viral diarrhea viruses (BVDVs) were isolated from cattle with respiratory and diarrhea signs as well as persistently infected cattle. These isolates were analysed serologically to characterize serogroups and to compare serological relationship with reference viruses of type I and II. Most isolates from calf diarrheal cases and persistently infected individuals showed a significant difference in cross-neutralization test with the viruses isolated from nasal discharges showing severe respiratory signs. Serologically most of the commercial vaccine strains could be classified into classical BVDV (type I) such as NADL strain. This serological difference among BVDV isolates suggested the need for new vaccines to protect cattle from both respiratory and enteric BVDV infections in field. The immunogenicity of BVDVs which showed a good propagation capability in MDBK cells and high rates of neutralizing activity (isolate : KD26-1, PHG, B5 and 95002) against all viruses used in this study, was confirmed in guinea pig when treated as single or combined groups.

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빈발도와 가중치를 이용한 서비스 연관 규칙 마이닝 (Mining Association Rule on Service Data using Frequency and Weight)

  • 황정희
    • 디지털콘텐츠학회 논문지
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    • 제17권2호
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    • pp.81-88
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    • 2016
  • 일반적인 빈발패턴 탐사 방법은 항목의 빈발도만을 고려한다. 그러나 유용한 정보를 추출하는 데 있어 빈발도와 더불어 고려해야 하는 것은 빈발항목이 아니더라도 연관된 항목이 주기적으로 함께 발생한다면 시기나 시간에 따라 관심의 중요도가 변화하는 것을 고려해야 한다. 즉, 시간에 따라 사용자가 요구하는 서비스의 중요도는 다르므로 각 서비스 항목에 대한 중요도의 값을 고려하여 마이닝 하는 방법이 필요하다. 본 논문에서는 서비스 온톨로지 기반으로 가중치를 이용한 서비스 빈발 패턴을 추출하는 마이닝 기법을 제안한다. 제안하는 기법은 시공간 상황을 기반으로 서비스의 중요도를 고려한 가중치를 부여하여 연관 서비스를 발견한다. 새롭게 탐사되는 서비스는 저장되어 있는 서비스 규칙과의 새로운 조합을 통해 사용자에게 최적의 서비스 정보를 제공할 수 있는 기반이 된다.

Service life prediction of a reinforced concrete bridge exposed to chloride induced deterioration

  • Papadakis, Vagelis G.
    • Advances in concrete construction
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    • 제1권3호
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    • pp.201-213
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    • 2013
  • While recognizing the problem of reinforcement corrosion and premature structural deterioration of reinforced concrete (RC) structures as a combined effect of mechanical and environmental actions (carbonation, ingress of chlorides), emphasis is given on the effect of the latter, as most severe and unpredictable action. In this study, a simulation tool, based on proven predictive models utilizing principles of chemical and material engineering, for the estimation of concrete service life is applied on an existing reinforced concrete bridge (${\O}$resund Link) located in a chloride environment. After a brief introduction to the structure of the models used, emphasis is given on the physicochemical processes in concrete leading to chloride induced corrosion of the embedded reinforcement. By taking under consideration the concrete, structural and environmental properties of the bridge investigated, an accurate prediction of its service life is taking place. It was observed that the proposed, and already used, relationship of service lifetime- cover is almost identical with a mean line between the lines derived from the minimum and maximum critical values considered for corrosion initiation. Thus, an excellent agreement with the project specifications is observed despite the different ways used to approach the problem. Furthermore, different scenarios of concrete cover failure, in the case when a coating is utilized, and extreme deicing salts attack are also investigated.

e-러닝 성과에 영향을 미치는 품질요인에 관한 연구 (What Quality Factors Affect to the e-Learning Performance)

  • 김성균;성행남;정대율
    • 한국정보시스템학회지:정보시스템연구
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    • 제16권1호
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    • pp.201-230
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    • 2007
  • Recently, the growth of e-Learning systems and its related information technology has presented a unique challenge for both schools and industry. It would make an extremely phenomenal paradigm shift in the educational method and practice. Methods of assessing the quality of e-teaming services and contents are critical issue in both practice and research. Moreover, many researchers are interested in what qualify factors more affect to the Performance of e-Learning service. Nevertheless, service quality is a construct that is difficult to define and measure. e-Learning services are composed of many factors, and they are more complicated than the traditional education services because they we performed on the distance basis and the many platforms of IT infrastructure. The purposes of our research are to classify the e-Learning service dimension and identify their factors, to develop the measurement of the factors, and finally to test empirically their relationship between the service factors and e-Learning service performance. For the development of the service factors we considered SERVQUAL model and SERVPERF model which were developed in the service marketing area. The SERVQUAL model was more fitted to the e-Learning services than the latter. From that we derived several factors that fit to our research domain, ie, tangibles, access, reliability, credibility, security, responsiveness, assurance, empathy. We combined three factors of them(reliability, credibility, security) into a factor, system stability for the semantic simplicity, and divided responsiveness factor into system operator responsiveness and teacher responsiveness as the entity based dimension classification. In the e-Learning services research, Most researcher are mentioned the quality factors of contents, so we added to two contents quality factors, ie, contents production method and richness of contents itself. We examined the relationship between the service quality factors and e-Learning performance(student satisfaction and service reuse intention). As result three quality factors(contents production method, teacher responsiveness, empathy) significantly affected student satisfaction. To the other performance variable, ie, service reuse intention, the teacher related quality factors(such as teacher responsiveness, assurance, empathy) affected only. In conclusion, even in the on-line distance teaming, the teacher's role md earnestness is as important as ever.

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마케팅조사의 결합분석법을 활용한 참고봉사의 평가에 관한 연구 (A Study on the Reference Evaluation Applying Conjoint Analysis of the Marketing Research)

  • 배순자
    • 한국문헌정보학회지
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    • 제21권
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    • pp.141-168
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    • 1991
  • The Purpose of this study is to explore and analyse ways of enhancing the effectiveness of reference service through reference evaluation. Marketing research technique combined with pre-evaluation theory was applied in this study to find out information for practice the service based on current concept of reference service. Aims and results of this study can be summarised as follows: First, the evaluation of effectiveness of reference service should be conducted for the purpose of finding out the ways of increasing user's satisfaction. Second, the policy evaluation was understood as the appropriated evaluation concept. The policy evaluation in principle coincides with reference service in sense that the satisfaction of public should have priority and hence be the criterion of the evaluation. Third, marketing research based on recently developed 'marketing concept', which concentrates all its efforts to meet user's demand and attempt to acquire the information for better marketing management of non-profit organization such as library, is examined to find out the evaluation method practically applicable to the pre-evaluation of reference service. In this study , conjoint analysis was adopted as the method of pre-evaluation about reference service. The Reference Room of the Central Library Yonsei University, was selected as the arget sample to find out the expected condition for the maximization of the user's satisfaction from the reference service. Based on this example study, the analysis indicates as the most desirable combination for reference service in terms of the user's satisfaction is following condition: the younger librarian with aimable personality who displays willingness In his/her assistance, plus as the method of reference service, sufficient and practical introduction to the reference materials available, plus immediate and satisfactory result of the service, and finally a library equipped with inter-library use system.

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