• 한국경영과학회지
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• 제37권3호
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• pp.95-116
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• 2012

The purpose of this paper is to show the effect of information sharing strategy on the supply chain performances. While traditional information sharing models assumed centralized stock information, recent supply chain practices often implement fully shared stock information, where real-time stock information is accessible on retailers. When retailers are competing with each other, this fully shared stock information may incur retailers' strategic order behaviors. Thus, this paper analyzes a simple two-level supply chain consisting of one warehouse and two identical competing retailers where the real time stock information is fully shared. The warehouse uses the traditional echelon stock policy. Under this environment the retailers' reorder decisions are derived using the order risk concept and the retailer competition mechanism is analyzed. Computational results show that the supply chain performace degradation in the fully shared stock information is quite significant, implying the importance of designing information sharing strategies in the supply chain design phase.

• 산업공학
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• 제13권3호
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• pp.444-454
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• 2000

Due to the improvement of modern information technologies, sharing stock information among the supply chain members is a common practice nowadays. Many companies are planning to adopt the information systems to possess the real-time shared stock information. Thus, it is needed to quantify the value of shared stock information. The purpose of this paper is to evaluate the value of the shared stock information for two-echelon distribution systems. Existing reorder policies can be classified into installation stock policies and echelon stock policies. Since installation stock policies do not utilize the shared stock information, and both classes of policies may show poor performances for distribution systems, we cannot evaluate the value of the shared stock information with the existing policies. Thus, we provide a new type of reorder policy, named order risk policy. We define the order risk using marginal analysis, and prove the optimality. Through computational experiment that compares the order risk policy with the existing policies, it is shown that a significant cost reduction is achieved with the effective utilization of the shared stock information. We also show the effect of the system characteristics on the value of the shared stock information.

• Journal of Computing Science and Engineering
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• 제5권1호
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• pp.1-18
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• 2011

As the first step toward real-time multi-core computing, this paper presents a novel approach to bounding the worst-case performance for threads running on multi-core processors with shared L2 instruction caches. The idea of our approach is to compute the worst-case instruction access interferences between different threads based on the program control flow information of each thread, which can be statically analyzed. Our experiments indicate that the proposed approach can reasonably estimate the worst-case shared L2 instruction cache misses by considering the inter-thread instruction conflicts. Also, the worst-case execution time (WCET) of applications running on multi-core processors estimated by our approach is much better than the estimation by simply assuming all L2 instruction accesses are misses.

• Journal of Communications and Networks
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• 제9권2호
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• pp.198-209
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• 2007

This paper provides a thorough study on shared segment protection (SSP) for mesh communication networks in the complete routing information scenario, where the integer linear program (ILP) in [1] is extended such that the following two constraints are well addressed: (a) The restoration time constraint for each connection request, and (b) the switching/merging capacity constraint at each node. A novel approach, called SSP algorithm, is developed to reduce the extremely high computation complexity in solving the ILP formulation. Basically, our approach is to derive a good approximation on the parameters in the ILP by referring to the result of solving the corresponding shared path protection (SPP) problem. Thus, the design space can be significantly reduced by eliminating some edges in the graphs. We will show in the simulation that with our approach, the optimality can be achieved in most of the cases. To verify the proposed formulation and investigate the performance impairment in terms of average cost and success rate by the additional two constraints, extensive simulation work has been conducted on three network topologies, in which SPP and shared link protection (SLP) are implemented for comparison. We will demonstrate that the proposed SSP algorithm can effectively and efficiently solve the survivable routing problem with constraints on restoration time and switching/merging capability of each node. The comparison among the three protection types further verifies that SSP can yield significant advantages over SPP and SLP without taking much computation time.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.140.3-140
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• 2001

This paper analyzes a blocking that is due to shared resource in multiprocessor system. A proposed analysis for shared resource suggests a scalable and amendable scheduling method about task allocation. An equation of shared resource blocking is proposed by a throughput at common bus and a ratio of throughput during time period, it is included a parameter of tasks scheduling. Using this equation, a new guideline for task allocation of multiprocessor is presented. Finally, in proposed system a model simulations for the proposed blocking model is given by a deterministic ratio of shared resource.

• KIEAE Journal
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• 제5권4호
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• pp.25-32
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• 2005

In apartment complexes of Korea shared space becomes more and more important since it promotes social relationship among neighbors and also as a ecological point of view. After the Green Building system was introduced in the society, it attracted more attentive as an essential component for sustainable community. Now, it's expected the shared space plan or the community center plan will be a hot issue in the society. Therefore, we could see an aspect of the gradual change related to housing culture in Korea and make a prediction how to develop the shared space as researching domestic leading studies about the 'shared space'. The purpose of this study is to identify the trend of academic achievement as shared spaces. 14 books and 43 studies are searched and each of them are divided into according to the subject. The concept of the shared space was introduced in a holistic moment and the design plans were presented in books in the early 1990's, and total community center it was introduced. The studies are naturally divided into 4 parts as time passed that are characteristics of the block planning in the complex, the needs of the shared space, the actual condition of the using shared space, and the case studies of the shared space. The shared spaces under the structure of the community center are expected to be developed in a more elaborate way to cope with increasingly well-being needs.

• Journal of Computing Science and Engineering
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• 제6권1호
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• pp.12-25
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• 2012

For real-time systems it is important to obtain the accurate worst-case execution time (WCET). Furthermore, how to improve the WCET of applications that run on multicore processors is both significant and challenging as the WCET can be largely affected by the possible inter-core interferences in shared resources such as the shared L2 cache. In order to solve this problem, we propose an innovative approach that adopts a code positioning method to reduce the inter-core L2 cache interferences between the different real-time threads that adaptively run in a multi-core processor by using different strategies. The worst-case-oriented strategy is designed to decrease the worst-case WCET among these threads to as low as possible. The other two strategies aim at reducing the WCET of each thread to almost equal percentage or amount. Our experiments indicate that the proposed multicore-aware code positioning approaches, not only improve the worst-case performance of the real-time threads but also make good tradeoffs between efficiency and fairness for threads that run on multicore platforms.

• 대한임베디드공학회논문지
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• 제4권4호
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• pp.174-179
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• 2009

Due to digital convergence, mobile embedded systems need more functionalities and a fully fledged OS. Applications for such embedded systems are linked with many shared libraries available in the OS and access a large data set at launch time. This results in increased application launch time. In this paper, we propose two techniques for reducing the application launch time: lazy-loading and pinning. Lazy-loading defers loading shared libraries that are not used in the application at launch time, whereas pinning guarantees the residence of shared libraries and data used at launch time in the main memory.

• 한국도로학회논문집
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• 제14권3호
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• pp.163-171
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• 2012

수요대응형 교통수단(Demand Responsive Transit)은 변화하는 이동수요에 대응하는 탄력적인 교통수단으로 단순히 노약자와 장애인을 위한 복지교통 서비스의 영역이 아니라, 무선통신과 위치정보서비스(Location Based Service: LBS)의 발달로 인하여 도심형 수단으로 보다 효율적인 교통수단으로 자리매김하고 있다. 그러나 문전서비스(Door-to-Door)를 제공하는 수요대응형 교통수단 시뮬레이션에 적합한 상용툴의 부재로 인하여 알고리즘이나 차량 운행 요소를 면밀하게 분석하기 힘든 어려움이 있었다. 본 연구는 수요대응형 교통수단에 연관된 다양한 차량 운영계획과 알고리즘을 구현, 평가할 수 있는 시뮬레이션 환경을 제안한다. 문전서비스(Door-to-Door) 기반의 차량 운행 모형을 적용하기 위하여 확보되어야 하는 시뮬레이션 입력 데이터를 정의하고 있으며, 수요대응형 교통수단의 대표적인 범주에 속하는 실시간 합승 택시(Shared-Taxi) 서비스를 서울시 교통망과 택시 수요를 이용하여 적용하였다. 합승 택시 운행 계획을 위하여 Nearest Vehicle Dispatch(NVD)와 Insertion Heuristic(IH), 두 종류의 알고리즘을 제안하였으며, 제안된 시뮬레이션을 통하여 성능을 비교하였다. 또한, 합승(Ride-sharing)을 허용하지 않는 일반적인 택시와의 비교를 통하여 시스템 효율 향상과 서비스 품질 변화를 분석하였다.

• 아동학회지
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• 제37권2호
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• pp.111-125
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• 2016

Objective: This study aimed to examine the effects of attachment and shared time between mother and child and self-esteem on subjective well-being in late childhood. Methods: A total of 329 fifth and sixth graders in elementary school (183 boys and 146 girls) participated in the study. They responded to questionnaires regarding attachment and shared time between mother and child and the self-esteem and subjective well-being of children. The data were analyzed using SEM. Results: Attachment and shared time between mother and child had an indirect effect through self-esteem as well as a direct effect on the subjective well-being of children. Children who formed secure attachments and spent more time with their mothers showed a higher level of subjective well-being. In addition, when children kept a good relationship with their mother quantitatively as well as qualitatively, they acknowledged their own capability and value positively, which led to higher subjective well-being. Conclusion: Findings emphasize that mother-child relationships play significant roles in predicting both the subjective well-being and self-esteem of children. The importance of self-esteem was identified in late childhood based on its relative influence on subjective well-being compared to mother-child relationships.