• 한국경영과학회지
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• 제30권3호
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• pp.137-149
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• 2005

This study proposes a framework enhancing the accuracy of estimation for project duration by combining linear Bayesian updating scheme with the learning curve effect. Activities in a particular project might share resources in various forms and might be affected by risk factors such as weather Statistical dependence stemming from such resource or risk sharing might help us learn about the duration of upcoming activities in the Bayesian model. We illustrate, using a Monte Carlo simulation, that for partially repetitive projects a higher degree of statistical dependence among activity duration results in more variation in estimating the project duration in total, although more accurate forecasting Is achievable for the duration of an individual activity.

• 패션비즈니스
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• 제3권1호
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• pp.138-146
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• 1999

For an enterprise to survive in extremely competitive world, it had better to down budget and resource of unimportant fields so that the enterprise can concentrate resources on the strong field. Nowadays in Korea, it is important to research outsourcing for strengthen the competitive power in apparel maker because of recent depression. The questionnaire was composed of 14 factors about outsourcing effect. The questionnaires were selected for finial analysis 67 apparel makers in Pusan and Seoul and data was analysed by using paired t-test by SPSS program. Almost of apparel makers (85.07%) has been outsourced the sewing process to contractor or vendor. Outsourcing in this case is marked lower effect than insourcing except reducing cost, economy of time and overcoming internal resources. This means that our outsourcing has been progressed with so many risk. If we have research the successful outsourcing and have a strategic vision and plan with vendor and product mutually beneficial relationship, we can share the risk and creating new business synergies through outsourcing.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2008년도 한국컴퓨터종합학술대회논문집 Vol.35 No.1 (B)
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• pp.24-29
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• 2008

여러 개의 작업이 동시에 작동 할 때 서로 다른 작업에서 특정한 로봇이나 장치를 사용하기 위하여 상대방의 작업이 끝나기를 기다리는 상태를 교착상태라 하며 생산공정에서는 효율성과 경제성 제고에 가장 중요한 문제 중 하나다. 지금까지 이러한 교착상태 확인은 도달성(reachability)기법이나 서브넷(Subnet)으로 분리하여 분석하는 기법 등이 가장 많이 사용 되었으나, 분석에 필요한 시간과 노력, 복잡성과 효율성에 있어서 효과적이지 못한 단점을 가지고 있다. 본 연구는 페트리넷(Petri Net)에서 모든 플레이스(Place) 간의 관계를 나타내는 추이(Transitive)행렬을 이용하여 교착상태가 나타날 가능성이 있는 자원공유 플레이스(Place)를 분석하여 교착상태를 검증하는 정책을 제시한다. 이를 위하여 교착상태를 확인할 수 있는 자원공유 플레이스의 관계를 정의하고, FMS(Flexible Manufacturing System) 모델을 이용하여 제안한 알고리즘의 성과를 검증한다.

• 경영과학
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• 제12권2호
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• pp.89-103
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• 1995

Traditionally, the scarce and expensive resources in communication networks has been the bandwidth of transmission facilities; accordingly, the techniques used for networking and switching have been chosen so as to optimize the efficient use of that resource. One of them is the packet switching for data communications, which is much different from the circuit switching. It allows multiple users to share the data network facilities and bandwidth, rather than providing specific amounts of dedicated bandwidth to each users. One main challenge therefore has been to design and build cost-effective packet switching networks. In this paper, we develop a mathematical programming medel and heuristic algorithm for designing the packet switching networks with hop-count constraints. To develop an efficient heuristic, we apply the Lagrangian relaxation method. Some valid inequalities, which have been known as the tight constraints, are considered to improve the bound for Lagrangian sub-problem. The computational experiments show that the performance of the proposed heuristic is very satisfactory in both the speed and the quality of design solutions generated.

• 한국태양광발전학회지
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• 제6권1호
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• pp.86-91
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• 2020

Nepal is among the richest in terms of water resource availability and it is one of the most important natural resources of the country. Currently, 72% of the population is electrified through the national grid system. The power generation mix into the grid is hydro dominated with minor shares generated from solar and thermal (accounts for less than 1%). To achieve sustainable development in the power sector it is essential to diversify power generation mix into the grid. Knowing the facts, the government has a plan to achieve a 5-10% share of power generation from solar and mix it into the grid system. Solar is the second most abundant, prominent and free source of renewable in the context of Nepal. This study mainly focuses on the grid-connected solar system, its importance, present status, government efforts, and its need. It is based on the review of literature, news published in national newspaper online news and international organization's report.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2012년도 춘계학술발표대회논문집
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• pp.166-167
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• 2012

High packet loss rate and impatience of messages passing through optical switches are essential characteristics in Optical Burst Switching system equipped with Optic Delay Lines buffer, which have not been solved efficiently yet by current existing models. In order to capture both effects, this paper introduces an analytical model from the viewpoint of classical queuing theory with impatient customers. We then apply it to evaluate and compare two wavelength-sharing cases, (1) all delay lines share a common wavelength resource and (2) each wavelength is associated with a number of delay lines. Our numerical results suggest to implement the first case because of lower packet loss rate for a fairly broad range of traffic load.

• Journal of Communications and Networks
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• 제10권3호
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• pp.331-337
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• 2008

In this paper, we investigate survivability in wavelength division multiplexing (WDM) mesh networks and propose a new algorithm called improved shared-path protection (ISPP) to completely tolerate the double-link failures. Compared with previous algorithms for protecting double-link failures, i.e., shared-path protection (SPP) and shared-link protection (SLP), the advantage of ISPP is to allow primary paths and backup paths to share the mixed wavelength-links based on the proposed new rules in which some primary wavelength-links can be changed to mixed wavelength-links, which can be shared by primary paths and backup paths. In addition, some mixed wavelength-links also can be shared by different backup paths for saving resources. Simulation results show that ISPP algorithm performs better in resource utilization ratio and blocking probability than conventional SPP and SLP algorithms.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2007년도 춘계학술발표대회
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• pp.751-754
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• 2007

본 연구에서는 유연생산시스템에서의 교착상태 확인 및 회피 알고리즘을 추이적 행렬을 이용하여 제안한다. 추이적행렬은 플레이스와 플레이스간의 관계를 표현함으로 마킹의 흐름을 플레이스와 트랜지션간의 관계형에서 상태와 상태간의 관계를 표현함으로 상태의 변화 검증에 편리하다. 교착상태 확인 및 회피 알고리즘을 제시하고, 기존에 발표되어진 siphon과 DAPN알고리즘간의 비료 검토를 통하여 제안한 알고리즘의 유용성을 검증하였다.

• Genomics & Informatics
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• 제1권2호
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• pp.75-79
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• 2003

Every protein can be characterized by either a distinct motif or a combination of motifs. Nevertheless, little is known about the relationships among (more than two) the motifs. Some of the proteins in the world are share motifs for evolutional or other biological benefits - they can save energy, time and resource for controlling and managing a variety of proteins. In some cases of motifs, the tendency is quite common and they can act the 'hub' motif of a network of the motif associations. The hubs are structurally and functionally important in themselves and also important in disease-related mutations. They will be highly resistant mutation to conserve their functions. But, in case of the a rare mutation, mutations on the position of hub can more easily cause fatal diseases.

• 정보학연구
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• 제3권1호
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• pp.117-124
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• 2000

본 논문은 설계 자동화를 위한 저전력 하드웨어 할당 알고리듬을 제안한다. 제안한 알고리듬은 스케줄링의 결과를 입력으로 받아들이고, 각 기능 연산자에 연결된 레지스터 및 연결 구조가 최대한 공유하도록 제어스텝마다 연산과 기억 소자의 상호 연결 관계를 고려하여 기능 연산자, 연결 구조 및 레지스터 할당한다. 또한 자원의 수를 최대로 줄임으로써 할당 과정동안 저전력의 요소인 캐패시턴스를 동시에 줄인다. 제안된 알고리듬은 비교 실험을 통하여 기존의 저전력을 고려하지 않은 방식들과 비교함으로서 본 논문의 효율성 을 보인다.