• Journal of the Korean Data and Information Science Society
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• 제21권3호
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• pp.605-619
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• 2010

Caching of frequently accessed data in multi-hop ad hoc environment is a technique that can improve data access performance and availability. Cooperative caching, which allows sharing and coordination of cached data among several clients, can further en-hance the potential of caching techniques. In this paper, we propose a fuzzy cooperative caching scheme in mobile ad hoc networks. The cache management of the proposed caching scheme not only uses adaptively CacheData or CachePath based on data sim-ilarity and data utility, but also uses the replacement manager based on data pro t. Also, the proposed caching scheme uses a prefetch manager. When the TTL of the cached data expires, the prefetch manager evaluates the popularity index of the data. If the popularity index is larger than a threshold, the data is prefetched. Otherwise, its space is released. The performance of the proposed scheme is evaluated analytically and is compared to that of other cooperative caching schemes.

• 한국경영과학회지
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• 제37권3호
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• pp.117-134
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• 2012

We analyze a systematic relationship between transaction mechanisms and wholesale pricing schemes within a supply-chain with two competing suppliers and a monopolistic retailor. When one of the suppliers changes its transaction mechanism from an independent scheme to a cooperative one, then the wholesale prices of the suppliers become cheaper than before. When one supplier changes its transaction scheme to a cooperative one while the other supplier sticks to the existing independent transaction scheme, we show that the supplier with a cooperative transaction scheme can realize the increased profit via a profit sharing contract with the retailer but the supplier with independent transaction scheme can face the decreased profit. We also show that both suppliers can achieve the higher profits by adopting the cooperative schemes with the retailer.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2001년도 Australian-Korean Rheology Conference 2001
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• pp.159.1-159
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• 2001

• 대기
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• 제23권3호
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• pp.357-365
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• 2013

A public-academia cooperative research system is suggested to improve the level of national research on atmospheric science and to enable the National Institute of Meteorological Research (NIMR) to meet its overloaded demand for research and results. As a practical example of cooperative research the CIRES case was reviewed. CIRES, the Cooperative Institute for Research in Environmental Sciences, located at the University of Colorado Boulder, is one of NOAA's 18 cooperative research centers located at universities across the U.S. NOAA, the National Oceanic and Atmospheric Administration, as a part of government, gives clear guideline for research topics and supplies research funds to research centers and audits their research processes and accomplishments. NOAA Boulder Laboratories, as a large, well-established government research center managed by government scientists, supplies depth of experiences and major research infra-structure to CIRES. CIRES pursues innovative and challenging research with their younger and brand-new researchers who are university employees. This cooperative work between government research organizations and the university produces high level research efficiently. Not only does Boulder have a beautiful natural setting where researchers live and work but also the city is a home to many scientific agencies and research facilities. This robust scientific network provides rich opportunities for CIRES researchers to collaborate with others in their scientific fields.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권10호
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• pp.4231-4245
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• 2020

Non-orthogonal multiple access (NOMA) is widely studied in both academia and industry due to its high spectral efficiency over orthogonal multiple access (OMA). To effectively improve spectrum efficiency, an amplify-and-forward (AF) cooperative NOMA system is proposed as well as a novel detection scheme is proposed, in which we first perform successive interference cancellation (SIC) twice at U1 for the two signals received from two time slots to remove interference from symbol 2, then two new signals apply max ratio combining (MRC). In addition, a closed-form upper bound approximation for the ergodic capacity of our proposed system is derived. Monte-Carlo simulations and numerical analysis illustrate that our proposed system has better ergodic capacity performance than the conventional cooperative NOMA system with decode-forward (DF) relay, the conventional cooperative NOMA system with AF relay and the proposed AF cooperative NOMA system in [16]. In addition, we can see that ergodic capacity of all NOMA cooperative systems increase with the increase of transmit SNR. Finally, simulations display that power allocation coefficients have little effect on ergodic capacity of all NOMA cooperative systems. This is due to this fact that ergodic capacity of two symbols can be complementary with changing of power allocation coefficients.

• 한국지구과학회지
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• 제22권5호
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• pp.360-376
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• 2001

본 정성적 연구는 협동학습에 대한 현직 과학교사들의 인식과 교실 현장에서 협동학습의 실천에 따른 장애요소들을 조사하였다. 구성주의 인식론을 배경으로 하고 있는 협동학습은 내용의 단순암기와 경쟁을 통한 학업성취를 조장하는 현재의 교육체계에 대한 하나의 대안적 틀로서 제시되었다. 2001년 여름 1급 정교사 자격연수에 등록한 18명의 현직교사들과의 심층 인터뷰를 통하여 수집한 면접자료는 ‘협동학습에 대한 교사들의 정의, 교실에서의 협동학습의 실천과 관련된 이슈들, 교사 및 학생들의 협동학습에 대한 반응’ 등의 세 가지 측면에서 분류, 분석되었다. 이 영역들은 다시 10개의 주제들로 다시 세분되었다: 교사들이 느낀 협동학습의 의미, 학습에서 대화의 중요성, 협동학습이(부)적절한 상황, 협동학습 수업의 마무리 방법들, 협동학습시의 조편성 방법, 협동학습의 실행에 있어서의 장애요소들, 협동학습에 대한 학생들의 반응, 교사들이 밝힌 학습중심 교수/학습 방법 선택(또는 거부)의 이유, 협동학습법을 선호하는 교사들의 특성, 교사들이 현장에서 협동학습을 거부하는 이유. 각 주제별로 교사들의 반응을 상술하고 토의를 제시하였다. 보다 많은 교실에서의 협동학습의 개발과 실행을 위해서는 (1) 교사들의 인식 전환의 필요성, (2)교사 재교육 기회의 제공, (3) 학생들의 새로운 역할에 대한 적응, (4) 교육과정 및 학습자료 측면의 지원 및 (5) 행정적, 시설적지원 등이 필요함을 주장하는 바이다. 한편, 협동학습이 모든 수업상황이나 교수/학습적 문제들에 있어서 만병통치약이 아니라는 것을 기억해야 한다. 협동학습은 단지 하나의 수업방법 또는 도구로서 가르치고자 하는 특정한 교수목표를 위해 유용하며, 특히 다양한 학습능력을 가진 학생들이 함께 섞여있는 교실에 적절한 방법이다. 후속 연구과제도 제안되었다.

• 한국문헌정보학회지
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• 제29권
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• pp.257-279
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• 1995

Cooperative program planning and teaching is a strategy for developing and implementing resource based learning. This approach combines the classroom teacher's subject expertise and knowledge of the students with the teacher­librarian's specialized knowledge of the availability and use of learning materials. And the purpose of cooperative program planning is to develop learning experiences or units of study that effectively integrate the student's resource center activities with other learning experiences. There are also some conditions that are conducive to effective planning sessions. First, the teacher-librarian must be prepared to initiate planning with teachers, rather than waiting for teachers to come to them. Second, the teacher-librarian must be prepared to present suggestions in such a way that the teacher can respond. The purpose of this study is (1) to investigate the planning process of cooperative program planning and teaching in the previous studies and (2) to find general problems when the cooperative program planning and teaching apply in actual situation. For these purposes, I chose a school library and a teacher-librarian in Seoul to observe how this cooperative program planning and teaching carry out in the school library. Main findings are summarized as follows: (1) A teacher who teaches alone for one grade is more proper to carry out the cooperative program planning and teaching. Young teachers are usually more active to change their teaching methods. (2) The cooperative program planning and teaching is a program what needs a lot of materials. When there is no right reference book in a school library, it would be good to access DB through PC telecommunication. It is also possile to contact lirarians who work in large public libraries or university libraries. (3) The cooerative program planning and teaching needs cooperative working between a teacher-librarian and a teacher. Thus a teacher-librarian should be in his school in the day time like the other teachers for the program's planning process. ( 4) There has to be a guide to change into resource based learning in teaching method. Thus the Korean Library Association or Korean Library and Information Science Society should offer a seminar or a workshop about cooperative program planning and teaching for the teacher-librarians. (5) It needs a system that a teacher-librarian can know about student's assignments so that he can prepare reference books for them. (6) The school library can be able to offer excellent service like cooperative program planning and teaching to the teachers and students according to a teacher-librarian's enthusiasm.

• 영재교육연구
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• 제15권1호
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• pp.11-36
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• 2005

과학영재학교의 교육과정 운영과 교과지도 방법에 협력교수가 중요한 개념으로 등장하게 되었다. 본 연구에서는 협력교수의 관점에서 과학영재학교의 교육과정 운영을 살펴보고, 사회과의 교수-학습과정에 적용할 수 있는 협력교수 방안과 실현 가능성을 탐색하였다. 이에 본 연구에서 살펴본 것과 그 결과는 다음과 같다. 첫째, 협력교수의 개념을 정리하고 여러 교육현장에서 이 개념에 근거한 방법적 적용들이 어떠한가를 살펴보았다. 둘째, 협력교수의 관점에서 현재 과학영재학교에서 이루어지고 있는 전 교과의 교수-학습을 살펴보았다. 셋째, 현재의 교육과정과 주어진 여러 물리적.인적 여건을 고려하여 사회과의 협력교수 방안을 탐색하였다. 넷째, 협력교수의 한 방안으로 제시된 '세미나 수업'의 일부분을 시행하였다. 세미나의 대주제는 시사성이 있는 통합적 주제로 '중국의 고구려사 왜곡 문제'였으며, 지리, 역사, 일반사회, 윤리 및 사상을 담당하는 교사와 희망한 학생들이 영역별 소주제를 중심으로 연구와 협력학습이 진행되었다. 다섯째, 세미나 준비와 발표등의 과정에서 교사-교사, 학생-학생, 교사-학생의 상호작용이 활발하게 있었고, 특히 교사들 간의 상호작용은 협력교수로 발전할 수 있는 가능성을 찾게 되었다. 마지막으로, 학생들은 사회과 학습에 적극적으로 참여하려는 공감대를 형성할 수 있었고, 사회현상에 대해 연구하는 방법을 익히고 동시에 사회현상을 다각적인 관점에서 접근할 수 있는 안목을 넓히게 되었다.

• 한국항공운항학회지
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• 제28권2호
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• pp.1-11
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• 2020

This study was carried out to verify how much instructor's communication skill affects the student pilot's study motivation and satisfaction. The instructor's communication styles are classified into 3 groups by pre-analysis. Three types are cooperative type, control type and professional type. Intellectual cause, performance proficiency cause, social cause and stimulation avoidance cause are extracted and analyzed for the cause of study motivation. Cooperative and control type affected all of 4 factors of student's study motivation by influence analysis. Intellectual cause affected control and cooperative type positively, especially more to cooperative type. Performance proficiency cause also had positive influence to control and cooperative type. Stimulation avoidance cause didn't appear to affect all sub-classified 4 factors of instructor's communication type. Influence analysis of student's study satisfaction from instructor's communication style showed that independent variable affected all sub factors positively. Degree of positive influence affected the control type the most, cooperative type was the 2nd, and professional type was the 3rd.

• 대한조선학회논문집
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• 제42권3호
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• pp.276-283
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• 2005

The cooperative production system was proposed as an efficient production system to reduce the ship construction cost and to enhance the competitiveness for small/medium sized shipbuilder in the previous paper. In viewpoint of cooperative production system, the specialization of the FRP ship sizes has already been accomplished to reduce the number of the hull molds by FRP shipbuilders of the Sapjin industrial complex located in Mokpo area in 2003. There also exist lots of effective methods, as a cooperative production system, to cut down the construction cost. In this study, an effective production system in connection with the super structure and outfitting members is proposed such as the standardization of those items and specialized company which intensively produces the super structure and outfitting members at the collectivization area for cooperative work.