• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권3호
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• pp.1301-1318
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• 2017

In order to utilize the licensed channel of cognitive radio (CR) when the primary user (PU) is detected busy, a benefit-exchange access mode based on cooperative communication is proposed to allow secondary user (SU) to access the busy channel through giving assistance to PU's communication in exchange for some transmission bandwidth. A holistic joint optimization problem is formulated to maximize the total throughput of CR system through jointly optimizing the parameters of cooperative spectrum sensing (CSS), including the local sensing time, the pre-configured sensing decision threshold, the forward power of cooperative communication, and the bandwidth and transmission power allocated to SUs in benefit-exchange access mode and traditional access mode, respectively. To solve this complex problem, a combination of bi-level optimization, interior-point optimization and exhaustive optimization is proposed. Simulation results show that, compared with the tradition throughput maximizing model (TTMM), the proposed holistic joint optimization model (HJOM) can make use of the channel effectively even if PU is busy, and the total throughput of CR obtains a considerable improvement by HJOM.

• 한국문헌정보학회지
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• 제56권3호
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• pp.265-290
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• 2022

본 연구는 한국과학기술정보연구원의 OA논문 통합서비스플랫폼(Discover)에 대한 비용편익분석을 통해 사업의 경제성 평가를 수행하였다. 학술연구자 1,313명, 바이오산업 연구개발자 49명, 일반 산업체 연구개발자 102명 등 서비스 수혜 집단별로 설문조사를 실시하여 편익측정에 필요한 기초자료를 수집하였다. 시스템 구축과 운영에 소요되는 비용, 직접편익과 간접편익을 추정한 후, 이를 토대로 비용편익분석과 민감도 분석을 실시하였다. 우선 직접 편익에 한정한 비용편익분석 결과, 총 8년간 사업에 투입된 사업투자비용(약 56.3억)의 약 14배인 820억 원의 편익이 발생할 것으로 추정되었다. 직간접편익을 합산한 비용편익분석 결과 역시 BCR이 최소 98.9, NPV는 5,388억 원 등으로 추정되어 사업의 경제적 타당성이 충분히 확보되었다. 본 분석 결과는 국가 차원의 OA논문 통합서비스플랫폼 개발 및 구축의 타당성 확보에 기여할 수 있으며, 본 연구에서 개발된 편익추정모형은 향후 사업 진행 과정에서 평가도구로 활용될 수 있을 것이다.

• 환경생물
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• 제22권2호
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• pp.259-264
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• 2004

생물다양성협약에서 국가 생물유전자원의 주권을 인정함에 따라 국가별로 생물유전자원의 관리에 대한 법적인 체계를 갖추어야 할 시기가 도래하였다. 생물유전자원의 관리에 있어서 가장 중요한 단계가 접근과 생물자원에서 파생하는 이익공유이다. 제6차 생물다양성협약 당사국 회의에서 채택된 본 지침은 접근과 이익공유과정에서 필수적인 상호합의조건과 사전통보승인제도를 포함하고 있다. 상호합의조건은 원산국과 이용 실체간의 계약 협정이고 사전통보승인제도는 생물자원 접근 전에 승인하는 것과 관련된 생물유전자원 관련 특이 제도이다. 아울러 국가연락기관과 국가책임기관의 책임, 유인조치 등에 관한 내용을 포함하고 있다. 우리나라의 생물유전자원 접근 관련 법률을 분석해 볼 때, 생물유전자원에 대한 이익공유와 특허권 문제가 고려되어 있지 않다. 생물유전자원 접근규제와 체계적인 관리를 위해서 정보 유용화 및 공개, 지적재산권을 조절하는 기관과 기타 이해관계자의 조정을 위한 국가관할기관의 역할이 중요하다. 다만, 이런 국가적 접근규제가 생물다양성관련 연구를 저해하지 않아야 하고 생물다양성협약의 목적인 생물다양성의 보존과 지속 가능한 이용에 위배되어서는 안 될 것이다.

• 한국자원식물학회지
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• 제16권3호
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• pp.169-180
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• 2003

생물다양성은 유전적, 종적, 생태적 다양성의 총체이며, 작물 품종 개량, 전통의약 및 생명공학의 원재료가 된다. 생물 다양성 협약은 생물 다양성의 감소에 대처하기 위한 국제적 노력의 결실로서, 생물 다양성의 보전, 지속 가능한 이용, 그리고 유전자원의 이용으로 발생하는 이익의 공평한 공유를 목적으로 한다. 생물 다양성 협약은 이런 목적을 이루기 위해서 원산국은 유전자원에 대한 접근을 위한 조건을 조성해야 하며, 이용국은 유전자원으로부터 얻어진 이익을 상호 합의 조건과 사전 통보 승인 제도에 의해 공정하고 공평한 분배를 해야 하는 의무를 부여하고 있다. 이에 따라 각 국은 유전자원 접근 및 이익공유에 관한 법률을 제정하여 국가적으로 규제하려고 노력하고 있다. 우리나라의 경우 개발도상국의 유전자원에 대한 접근 규제뿐만 아니라 선진국의 생물 공학 기술에 대한 접근 규제로 인하여 유전자원 및 생물 다양성 연구에 있어서 어려움이 증가하고 있으며, 국내의 생물 다양성 연구를 발전시키기 위해서는 생물 다양성 보전과 유전자원 이용에 관한 국제동향을 파악하여 능동적으로 대처하는 것이 필요하다.

• 한국IT서비스학회지
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• 제12권4호
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• pp.59-75
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• 2013

As education environment is changing rapidly and competition of education industry is more intensive, the importance of service view about education is increasing as a differential competitive advantage. This study attempted to investigate the impact of service convenience as a different competitive advantage on e-learning acceptance by using TAM. The purpose of this study is to examine how five-dimensional service convenience constructs(decision convenience, access convenience, transaction convenience, benefit convenience, post-benefit convenience) affect consumers' perceived usefulness, attitude and usage intention. For this study, data were gathered from respondents who bought or used e-learning services and analyzed by structural equation model. Among the five-dimensional service convenience constructs, two constructs(benefit convenience, post-benefit convenience) affected consumers' positive perceived usefulness, attitude and usage intention about e-learning service. The results show that management and investment to improve benefit and post-benefit service convenience make consumers' positive attitude and usage intention about e-learning service.

• 한국정보통신학회논문지
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• 제12권1호
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• pp.108-114
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• 2008

플래시 메모리는 디스크와는 달리 덮어쓰기가 불가능하므로, 새로운 데이터는 새로운 영역에 갱신이 된다. 데이터가 빈번히 변경되면 새로운 영역을 확보하기 위해 가비지 컬렉션을 통하여 데이터를 지우게 되는데, 이때 지움(erase) 연산을 수행 할 수 있는 회수가 플래시 메모리의 특성에 의해 일정 회수로 제한을 받게 되므로 플래시 메모리의 모든 블록은 고르게 쓰여지고 지워져야 한다. 그러나 지역 접근성을 가지는 데이터를 Cost-benefit 방법으로 처리하면 성능은 좋으나 wear-leveling은 매우 나빠지는 문제점이 있다. 본 논문에서는 wear-leveling을 개선하기 위해 멀티 뱅크에서 하나의 뱅크는 cold 데이터를 다른 뱅크는 hot 데이터를 할당하고, 시간이 흐름에 따라 일정주기로 cold 뱅크와 hot 뱅크를 교환하는 CB-MB(Cost Benefit between Multi Bank) 방법을 제안하고 성능을 평가하였다. CB-MB방법은 hot 데이터와 cold 데이터를 블록단위로 분리하여 관리하는 Cost-benefit방법에 비해 성능에 있어 30% 성능향상을 보이고 wear-leveling측면에서 1/3이하로 표준편차를 줄였다.

• 한국통신학회논문지
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• 제39B권10호
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• pp.684-690
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• 2014

In this work we investigate the benefit of multicast in the delivery of video data over the mobile MBMS network. In order to quantify the benefit in a practical aspect, this work proposes an analytic framework that employs a combined statistical and queuing model, where a queuing model represents the behavior of user's access to the video service and the statistical model captures the popularity of the video contents, via which we draw out a more realistic intuition for the expected benefit from multicast. Finally, we present results of numerical experiment that illustrates the validity of the proposed work.

• 보건행정학회지
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• 제31권1호
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• pp.5-16
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• 2021

Both access to healthcare services and income security in case of personal illness are being needed to achieve universal health coverage, which is enshrined in the human rights to health and social security and international standards on social protection. Income security acts on both the social determinants and the adverse consequences of ill health and thus would break the vicious disease-poverty cycle. The government is supposed to implement a demonstration project of sickness benefit in 2022 and to publicize its more specific blueprint for all workers. This study is to suggest basic principles and a framework to design a new sickness benefit for universal health coverage, which is based on reviews on previous studies, related issues, and institutional conditions. This is to provide a theoretical basis to promote further discussion and to support its decision-making.

• 대한치과의사협회지
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• 제56권10호
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• pp.572-580
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• 2018

Adequate access cavity is the key to achieving endodontic success. The aims of the access cavity can be considered as follows: 1) Creation of a smooth unimpeded pathway for instruments to canal orifices 2) Removal of the entire roof of the pulp chamber in order to inspect the pulp floor, 3) Preservation of natural tooth substance consistent with the above. Recently, contracted endodontic cavities based on minimally invasive endodontics has introduced. This has the benefit of preserving the pericervical dentin more than traditional access cavity with achieving long-term success. However, some studies reported controversial results regarding root canal detection, instrumentation efficacy (noninstrumented canal area, hard tissue debris accumulation, canal transportation, and centering ratio) as well as fracture resistance. Therefore, further studies are required for accepting contracted access cavity, and modified form of traditional and contracted access cavity could be considered.

• 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.