• 한국정보시스템학회지:정보시스템연구
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• 제28권1호
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• pp.73-96
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• 2019

Purpose The purpose of this study is to examine the effect of communication-structure characteristics on performance in online collaboration using the data from Github, one of representative open source software development platforms. We analyze the impact of in-degree/out-degree centralization and reciprocity of communication network on collaboration performance in each project. In addition, we investigate the moderating effect of owner types, an individual developer or an organization. Design/methodology/approach We collect the data of 838 Github projects, and conduct social network analysis for measuring in-degree/out-degree centralization and reciprocity as independent variables. With these variables, hierarchical regression analysis is employed on the relationship between the characteristics of communication structure and collaborative performance. Findings Our results show that for the project owned by an organization, the centralized structure of communication is not associated with the collaboration performance. In addition, the reciprocity is positively related to the collaboration performance. On the other hand, for the project owned by an individual developer, the centralized structure of communication is positively related to the performance, and the reciprocity does not show the positive relationship on the performance.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권1호
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• pp.72-82
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• 2008

Various surgical approaches in the mandibular condyle fracture have been reported and many advantages of intraoral reduction were also introduced. But there are still controversies about surgical method of condylar fractures up to date. To establish the surgical approach protocol of condylar fracture, from May 2001 to December 2004, total 65 patients with 74 fractures of the mandibular condyle were reviewed during 2 years, retrospectively. All cases were classified according to the treatment considering factors, such as the level of fracture, degree and direction of displacement of fractured segment, patient’s age and gender, surgical approach methods, and their complications. Especially, advantages and surgical limitations of extraoral surgical approach, such as direct reduction and fixation via submandibular approach, Nam’s method, and endaural approach, were compared with those of intraoral surgical approach, such as direct intraoral reduction with transbuccal fixation or right angle driver system, and intraoral reinsertional approach after extraoral fixation of fractured fragment. The guidelines of surgical approach of condylar fracture based on our clilnical retrospective experiences and literature reviews can be suggested.

• 지능정보연구
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• 제15권2호
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• pp.15-31
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• 2009

차세대 전산환경은 사용자들이 필요한 전산자원을 네트워크를 통해 공급받는 그리드 컴퓨팅 기반의 개방형 전산환경으로 진화할 것으로 예상된다. 개방형 전산환경의 도입은 전산자원 활용의 효율성을 높이고 협업을 증진시키며 공급의 유연성과 비용 절감 등의 효과를 가져올 수 있다. 그러나 네트워크를 통해 공급되는 특성으로 인해 개방형 전산 자원의 성능에는 변동성이 수반된다. 전산자원의 성능에 변동성이 있는 경우, 주어진 예산과 시간만 고려하여 전산자원 서비스를 구성하는 단순 최적화 방법을 사용했을 때는 서비스의 최종 성능과 실행 시간 등을 규정한 서비스 수준계약(Service Level Agreement, SLA)을 만족시키지 못할 위험이 높다. 따라서 개방형 전산환경의 서비스 브로커는 전산자원 공급의 안정성을 높이기 위해서 서비스를 구성하는 개별 전산자원의 성능 변동성을 고려하여 위험을 최소화 하는전산자원포트폴리오를구성할것이요구된다. 본연구에서는평균절대편차(Mean-Absolute Deviation, MAD) 포트폴리오 최적화 기법을 이용하여 서비스 브로커의 공급 안정성을 향상시키는 방법을 제시하였다. 제시된 최적화 기법의 효과를 알아보기 위한 방법으로 가상의 개방형 전산환경을 모델링하고, 고객의 제약 조건과 개방형 전산환경의 변동성 정도에 따라 전산자원 공급 서비스의 성공률을 시뮬레이션 하였다. 시뮬레이션 결과로서, 첫째, 단순 최적화방법보다 변동성을 감안한 MAD 포트폴리오 최적화 기법을 이용했을 때 공급의 안정성이 뛰어난 것을 확인할 수 있었다. 둘째로는 특히 개별 전산자원의 변동성 예측의 정확성이 높아질수록 성능도 더욱 향상되는 결과를 가져왔다. 셋째, 측정된 변동성을 이용하여 개방형 전산자원의 가격을 할인하는 정책을 추진할 경우 서비스 공급 범위의 확대에도 효과가 클 것으로 예상되었다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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• pp.61-70
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• 1990

The information revolution is sweeping through the global economy. The strategic significance of the information and information technology have been some what underestimated. Now they are transforming the structure of competition. Information technology must be applied to improve and sustain an organization's competitive advantage. The successful implementation of information technology is dependent on the effectiveness of information systems planning. However, the selection of the right methodology still remains a open question. This paper describes the existing methodologies for information system planning. A complementary approach to strategic information systems planning, which was developed for a steel company, is suggested. The approach attempts to combine Business Systems Planning of IBM and Critical Success Factors Analysis for effective information systems planning. Although this approach is in the experimental stage it looks to be of benefit to large organizations which require information planning for managerial level.

• 셀메드
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• 제5권3호
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• pp.20.1-20.4
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• 2015

Ayurveda is often criticized for having empirical and non-evidence based approach to treat the patients. At the same time, modern medicine is also being criticized for having a non-holistic, reductionist and mechanistic approach of treating the patients which do not help in many real clinical situations. An open minded deduction of treatment approaches in both of these systems for a common patient however makes us to rethink that ideally both systems are similar with a common objective of offering a cure although in a manner which is better understood through their own methods of learning. The differences therefore, are more superficial rather than being deeply rooted in the understanding. A more tolerant viewpoint towards the competitive medical systems may therefore be a better approach to offer optimal health care to our people through a genuine amalgamation of these two health care sciences through an integrated approach. Once this tolerance is developed, it will give us an opportunity to think for a focused selection of type of health care depending upon the type of the disease and strength of the particular system in that area.

• 한국통신학회논문지
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• 제33권10A호
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• pp.980-986
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• 2008

Spatial multiuser access is investigated for the reverse link of multiuser multiple-input multiple-output (MIMO) systems. In particular, we consider two alternative a aches to spatial multiuser access that adopt the same detection algorithm at the base station: one is a closed-loop approach based on singular value decomposition (SVD) of the channel matrix, whereas the other is an open-loop approach based in space-time block coding (STBC). We develop multiuser detection algorithms for these two spatial multiuser access schemes based on the minimum mean square error (MMSE) criterion. Then, we compare the bit error rate (BER) performance of the two schemes and a single-user MIMO scheme. Interestingly, it is found that the STBC approach can provide much better BER performance than the SVD approach as well as than a single-user MIMO scheme.

• 대한관절경학회지
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• 제14권1호
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• pp.49-52
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• 2010

목적: 회전근 개 파열에서의 전외측 도달법을 이용한 소절개 봉합술을 소개하고자 한다. 수술 술기: 전신 마취하에 측와위 자세를 취한 후 후방 삽입구, 전방 삽입구를 이용하여 관절내 병변의 유무를 확인하고, 관절경을 견봉하 공간에 위치시킨 후 외측 삽입구를 이용하여 회전근 개의 파열 형태 및 크기를 파악한 후 관절경하견봉 성형술을 시행한다. 견봉의 전외측 연에서 하방으로 3~4 cm의 피부 절개를 가한 후 전방 및 중간 삼각근의 봉합선을 따라 박리하고 삼각근 견인기를 이용하여 시야를 확보한다. 파열된 건에 견인 봉합을 시행하여 해부학적 복원을 위한 위치를 확인한 후 봉합 나사를 이용하여 일열 혹은 이열 봉합술을 시행한다. 봉합술 후 견봉에서 삼각근이 견열되는 것을 방지하기 위해 1번 흡수봉합사를 이용하여 견봉과 삼각근과의 추가적인 봉합을 시행한다. 결론: 본 술기는 회전근 개의 가장 흔한 파열 부위인 극상건의 전방부에 직접 도달이 가능하고, 전방 및 중간 삼각근 사이로 접근하기 때문에 삽입구 연장 도달법에 비해 비교적 적은 견인으로도 시야를 확보할 수 있으며 전방으로는 견갑하건의 상부와 후방으로는 극하건까지 도달할 수 있는 유용한 술식으로 생각된다.

• 한국초등과학교육학회지:초등과학교육
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• 제29권2호
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• pp.207-218
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• 2010

The revised curriculum in 2007 adds an open inquiry approach to increase students' creativity and interest in science. Because it is the first time for elementary students to perform the open inquiry due to the national curriculum, it is essential that teachers give students' successful experiences in order to build a positive impression about inquiry activity. The purpose of this research is to develop and apply the open inquiry program. The research findings are as follows: First, we analyzed the students' traits of open inquiry ability during the program. The third and fourth grade students showed weakness in operating and inquiring abilities. They also feared failure and were unable to concentrate in classes which were based on explanation or discussion. When students had unexpected results, however, their inquiring abilities and creativeness increased considerably. Additionally there were some students who were stressed during the science-inquiry activity, due to no interest in science and an inability to think scientifically. Second, we developed an open inquiry program for elementary students. The program was modified, reflected upon the students' traits during open inquiry in class. Through repeated feedback like this, we completed the program. Third, for those who studied in the lessons there was a meaningful change in students' science inquiry abilities and abilities to perform 'formulating a hypothesis' and 'the control of variables'. These students' level of self-inquiry performance improved steadily. Moreover, they obtained a strong attachment to their inquiry and understood the method of quantitative experiments.

• Archives of Pharmacal Research
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• 제20권5호
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• pp.501-506
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• 1997

Novel 9-[2-fluoro-4-hydroxy-3-hydroxymethyl-2-butenyl]adenine and its related compounds were designed and synthesized as open-chain analogues of neplanocin A. Alkylation of adenine or pyrimidine bases with the mesylate 4 was chosen as a simple approach to the synthesis of 2-fluoro-2-butenylated nucleosides. Mesylate 4 was prepared from dihydroxyacetone dimer via four steps in 58% overall yield. The synthesized compounds were evaluated their antiviral activity against HSV, HIV and Polio viruses.

• 대한수학교육학회지:수학교육학연구
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• 제8권1호
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• pp.41-58
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• 1998

In this paper, we designed an open class teaching model in level-based team arrangements. In this way, teaching lesson plans were newly developed in order to teach students in open classroom environments. Both teachers and students required enough time to be acquainted with the new approach. However, empirical data analyses of mid-term and final examinations as well as survey data mathematical achievements indicated that most of the students have shown interests in mathematical activities and confidences on their mathematical abilities. Furthermore, there were few students who seemed to be isolated from mathematical activities. In particular, most students didn't seem to get lower grades than expected from other teachers who hesitated to apply the new model.