• 통상정보연구
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• 제8권1호
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• pp.325-336
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• 2006

This paper examines the global supply chain management strategy and business performance of Doolee Vision Co. Ltd.. Based on the analysis of eighty-seven cases, the following results were found. First, it was found that just-in-time of GSCM strategy of firm have a positive influences on the business performance in transformation sector. Second, just-in-time of GSCM strategy of firm have a positive influences on the business performance in custody sector. Third, just-in-time of GSCM strategy of firm have a positive influences on the business performance in order response and support sector. Forth, just-in-time of GSCM strategy of firm have a positive influences on the business performance in customs sector. Fifth, just-in-time of GSCM strategy of firm have a positive influences on the business performance in customer service sector. However, several limitations, such as measurement for intra-industry homogeneity, measurement for flexibility of global supply chain management strategy, and measurement for business performance of global supply chain management, that make the preceding conclusions be considered preliminary.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.329-332
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• 2000

Research interests on temporal data have been almost focused on data models. There has been relatively less research in the area of temporal data management. In this paper, we propose two data migration strategies based on time-segmented storage structure: the migration strategy by Time Granularity, the migration strategy by LST-GET. We describe the criterion for data migration and moving process. We simulated the performance of the migration strategy by Time Granularity in order to compare it with non-segmentation method. We compared and analyzed two data migration strategies for temporal data.

• KIEE International Transactions on Power Engineering
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• 제5A권2호
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• pp.177-185
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• 2005

This paper proposes an expert system that can enhance the accuracy of real-time bus reconfiguration strategy by adopting the local minimum tree search method and that can minimize the spreading effect of the fault by considering the operating condition when a main transformer fault occurs in an automated substation. The local minimum tree search method is used to expand the best-first search method. This method has the advantage that it can improve the solution performance within the limits of the real-time condition. The inference strategy proposed expert system consists of two stages. The first stage determines the switching candidate set by searching possible switching candidates starting from the main transformer or busbar related to the event. The second stage determines the rational real-time bus reconfiguration strategy based on heuristic rules from the obtained switching candidate set. Also, this paper proposes generalized distribution substation modeling using graph theory, and a substation database based on the study results is designed.

• 한국정밀공학회지
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• 제12권5호
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• pp.108-116
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• 1995

A tension control strategy for a multi-span web transport system is proposed. This strategy is developed by using the tension transfer phenomena in multi-span systems. The performance of this control strategy is compared with that of an existing control strategy through a computer simulation. A real-time software is designed based on the proposed tension control stration of master speed drive in tension control is demonstrated.

• 산업공학
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• 제20권3호
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• pp.407-417
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• 2007

Owing to a real-time innovative infrastructure driven by destructive technology revolution, the business environment has been changed dramatically. In order to respond fast to a continuously and unpredictably changing business environment, the business entities, such as business process participants, customers, distributers, and partners, should have an agile paradigm which is able to acquire and share the real time information adaptively. As a 21st century business paradigm having such adaptability and responsiveness has been introduced and called the "Real-Time Enterprise (RTE)" strategy. In this paper, we investigate the various innovation cases adopting the RTE strategy. After briefly addressing the concept and the value of RTE strategy, we discuss the models and the frameworks used in outstanding international and domestic enterprises. We believe that this case study can provide a good guide to many enterprises planning to adopt a RTE strategy for building competitive advantage in today's world of global competition.

• 한국정보과학회논문지:소프트웨어및응용
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• 제30권7_8호
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• pp.780-791
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• 2003

낮은 대여폭을 갖는 이동 컴퓨팅 환경에서 캐슁은 요구 경쟁을 감소시킴으로서 응답시간을 향상시킬수 있는 유용한 방법이다. 전통적인 캐쉬 기반의 시스템에서는 히트율을 향상시키는 것이 일반적으로 빠른 응답시간을 위한 주요한 관심사중의 하나였다. 그렇지만, 이동 컴퓨팅 환경에서는 히트율 뿐만 아니라 미스 비용의 고려도 필요하다. 본 논문에서는 풀 기반의 데이타 분산 시스템에서 새로운 캐쉬 대체 전략을 제시하고 시뮬레이션을 통하여 성능을 평가한다. 제시한 전략은 인기도와 대기 시간을 함께 고려하여 인기도와 대기 시간을 곱한 값 중에서 가장 작은 값을 갖는 페이지를 대체 페이지로 선정한다.

• 국제초고층학회논문집
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• 제3권2호
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• pp.155-165
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• 2014

This study measured and compared the variation of ventilation rate and fan energy consumption according to various control strategies after installing wireless sensor-based pilot ventilation system in order to verify the applicability of demand-controlled ventilation (DCV) strategy that was efficient ventilation control strategy for underground parking lot. The underground parking lot pilot ventilation system controlled the ventilation rate by directly or indirectly tracking the traffic load in real-time after sensing data, using vehicle detection sensors and carbon monoxide (CO) and carbon dioxide ($CO_2$) sensor. The ventilation system has operated for 9 hours per a day. It responded real-time data every 10 minutes, providing ventilation rate in conformance with the input traffic load or contaminant level at that time. A ventilation rate of pilot ventilation system can be controlled at 8 levels. The reason is that a ventilation unit consists of 8 high-speed nozzle jet fans. This study proposed vehicle detection sensor based demand-controlled ventilation (VDS-DCV) strategy that would accurately trace direct traffic load and CO sensor based demand-controlled ventilation (CO-DCV) strategy that would indirectly estimate traffic load through the concentration of contaminants. In order to apply DCV strategy based on real-time traffic load, the minimum required ventilation rate per a single vehicle was applied. It was derived through the design ventilation rate and total parking capacity in the underground parking lot. This is because current ventilation standard established per unit floor area or unit volume of the space made it difficult to apply DCV strategy according to the real-time variation of traffic load. According to the results in this study, two DCV strategies in the underground parking lot are considered to be a good alternative approach that satisfies both energy saving and healthy indoor environment in comparison with the conventional control strategies.

• Smart Structures and Systems
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• 제31권5호
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• pp.437-454
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• 2023

Real-time hybrid simulation (RTHS), which has the advantages of a substructure pseudo-dynamic test, is widely used to investigate the rate-dependent mechanical response of structures under earthquake excitation. However, time delay in RTHS can cause inaccurate results and experimental instabilities. Thus, this study proposes a model-based adaptive control strategy using a Kalman filter (KF) to minimize the time delay and improve RTHS stability and accuracy. In this method, the adaptive control strategy consists of three parts-a feedforward controller based on the discrete inverse model of a servohydraulic actuator and physical specimen, a parameter estimator using the KF, and a feedback controller. The KF with the feedforward controller can significantly reduce the variable time delay due to its fast convergence and high sensitivity to the error between the desired displacement and the measured one. The feedback control can remedy the residual time delay and minimize the method's dependence on the inverse model, thereby improving the robustness of the proposed control method. The tracking performance and parametric studies are conducted using the benchmark problem in RTHS. The results reveal that better tracking performance can be obtained, and the KF's initial settings have limited influence on the proposed strategy. Virtual RTHSs are conducted with linear and nonlinear physical substructures, respectively, and the results indicate brilliant tracking performance and superb robustness of the proposed method.

• 한국환경보건학회지
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• 제37권1호
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• pp.73-79
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• 2011

The growing interest in nanotechnology has resulted in increasing concern and a number of published environmental and workplace measurements for assessing occupational exposure to engineered nanomaterials. However, the amount of previous exposure data remains limited. Furthermore the data available was collected with extensive variation in terms of exposure measurement strategy, which limits the ability to pool the data in the future. In response, this paper reviewed several pertinent issues related to exposure measurement strategy to suggest a harmonized measurement strategy which would make exposure data more useful in the future, e.g. correlation between exposure metrics, relationship between activity and exposure, task-based or shift-based assessment, background concentration, limitation of personal exposure monitoring and other determinants of exposure/modeling. An improved sampling strategy for nanomaterial exposure assessment should be considered in order to maximize the use of the data from various real time monitoring instruments.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.324-329
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• 2000

Object of a real-time system, that performs exact information based on the real-time constraint. is required for an improvement of high reliability. The fault-tolerant task scheduling strategy of multiprocessor as using a distributed memory based on a hardware redundancy can be improved into a high reliability of the real-time system. Therefore, this paper is shown to analyze the reliability of the system by using the transfer parameter and make the modeling in reference to a minimization of the fault-tolerant task scheduling strategy which uses a percentage of task missing and deadline parameter based on optimization task size.