• Nuclear Engineering and Technology
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• v.37 no.1
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• pp.109-117
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• 2005

Limiting conditions for operations (LCOs) are evaluated dynamically using the tool of system dynamics. The LCOs de-fine the allowed outage times (AOTs) and the actions to be taken if the repair cannot be completed within the AOT. System dynamics has been developed to analyze the dynamic reliability of a complicated system. System dynamics using Vensim software have been applied to LCOs assessment for an example system, the auxiliary feed water system of a reference nuclear power plant. Analysis results of both full power operation and shutdown operation have been compared for a measure of core damage frequency. The framework developed in this study has been shown to be very flexible in that it can be applied to assess LCOs quantitatively under any operational context of the TS in FSAR.

• Journal of Intelligence and Information Systems
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• v.8 no.1
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• pp.119-139
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• 2002

In electronic catalogs, each item is represented as an independent unit while the parts of the item can be composed of a higher level of functionality. Thus, the search for this kind of product database is limited to the retrieval of most similar standard commodities. However, many industrial products need to configure optional parts to fulfill the required specifications. Since there are many paths in finding the required specifications, we need to develop a search system via the configuration process. In this system, we adopt a two-phased approach. The first phase finds the most similar template, and the second phase adjusts the template specifications toward the required set of specifications by the Constraint and Rule Satisfaction Problem approach. There is no guarantee that the most similar template can find the most desirable configuration. The search system needs backtracking capability, so the search can stop at a satisfied local optimal satisfaction. This framework is applied to the configuration of computers and peripherals. Template-based reasoning is basically the same as case-based reasoning. The required set of specifications is represented by a list of criteria, and matched with the product specifications to find the closest ones. To measure the distance, we develop a thesaurus of values, which can identify the meaning of numbers, symbols, and words. With this configuration, the performance of the search by configuration algorithm is evaluated in terms of feasibility and admissibility.

• Journal of Power System Engineering
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• v.20 no.4
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• pp.83-90
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• 2016

This study proposes a high-performance PI controller design method for an oil cooler system in conjunction with zero position adjustment and the characteristic parameters in its closed loop control system. The characteristic parameters included PI gains are decided by design specifications such as settling time and overshoot. The fine tuning on decided gains was performed by adjustment the zero position to get more desirable control performances. The simulations and experimental results show that the proposed PI controller design for an oil cooler system was possible to accomplish good control performances and to satisfy the design specifications.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1785-1790
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• 2010

This study examined the overall measurement system for the power dispersed high speed railway with 400km/h of maximum test speed. The measuring system evaluating an efficiency, stability and reliability is important for developing the high speed railway. In order to organize the comprehensive measuring system, it is needed to determined the test item, a number of channel and the specifications of the measurement system. In this study, we made lists for the performance evaluation tests of the next generation high speed railway expected to be developed in the future, and prepared generalization channel sheets for the specification of the overall measurement system. In addition, the specifications for the measuring system were discussed and synthesized.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.6
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• pp.589-597
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• 2017

This study aims to verify experimentally the specifications of the data acquisition system required for the precise measurement of signals in an underwater explosion (UNDEX) experiment. The three data acquisition systems with different specifications are applied to compare their precision relatively on maximum shock pressures from UNDEX. In addition, a method of assessing the acquired signals is suggested by introducing the concept of measurement uncertainty. The underwater explosion experiments are repeated five times under same conditions, and assessment is conducted on maximum quantities acquired from underwater pressure sensors. It is confirmed that the concept of measurement uncertainty is very useful method in accrediting the measurement results of UNDEX experiments.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1296-1299
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• 1996

This paper proposes a design automation method for the flight control system of an aircraft based on optimization. The control system design problem which has many specifications is formulated as multi-objective optimization problem. The solution of this optimization problem should be considered in terms of Pareto-optimality. In this paper, we use an evolutionary algorithm providing numerous Pareto-optimal solutions. These solutions are given to a control system designer and the most suitable solution is selected. This method decreases tasks required to determine the control parameters satisfying all specifications. The design automation of a flight control system is illustrated through an example.

• ETRI Journal
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• v.38 no.2
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• pp.337-346
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• 2016

We propose a data-driven kinematic control method for a robotic spatial augmented reality (RSAR) system. We assume a scenario where a robotic device and a projector-camera unit (PCU) are assembled in an ad hoc manner with loose kinematic specifications, which hinders the application of a conventional kinematic control method based on the exact link and joint specifications. In the proposed method, the kinematic relation between a PCU and joints is represented as a set of B-spline surfaces based on sample data rather than analytic or differential equations. The sampling process, which automatically records the values of joint angles and the corresponding external parameters of a PCU, is performed as an off-line process when an RSAR system is installed. In an on-line process, an external parameter of a PCU at a certain joint configuration, which is directly readable from motors, can be computed by evaluating the pre-built B-spline surfaces. We provide details of the proposed method and validate the model through a comparison with an analytic RSAR model with synthetic noises to simulate assembly errors.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.6
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• pp.731-743
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• 2018

In this paper, a study result to decide the accuracy specifications of inertial sensors satisfying the performance requirements of SINS(ship's inertial navigation system) is proposed. To do this, the performance specifications of overseas SINS is surveyed and the detailed error analysis of SINS at stationary condition is performed. Also, a new performance index to indicate the performance of SINS is derived. Modelling and simulation results show that the accuracy specifications of inertial sensors to meet the performance requirements of SIGMA40XP, a typical overseas SINS, can be determined through the newly derived performance index in this paper.

• The Journal of Society for e-Business Studies
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• v.4 no.3
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• pp.179-196
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• 1999

A cyber shopping mall is a place where consumers acquire the product information and make purchase decision in the cyber space. Even though there are many advantages over traditional malls, there are still several limitations to do shopping in an existing cyber mall. One of them is the absence of efficient search tool to handle various products specifications. Existing search systems usually support the "keyword search only" with limited product information. Consumers spend lots of their time and efforts in searching products and comparing them. Recently, some web sites provide the shopping mall comparison service that supports the additional search conditions such as price and maker. These services improve the situation but it is not still acceptable. In this paper, we propose an intelligent product search system based on a mediator which supports various conditional search for each product. Our system provides consumers with search results that satisfy purchase specifications. Our system is implemented in Visual basic and pert and experimental results show satisfactory performance.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.5
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• pp.1-10
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• 2002

This study is based on user requirements before the implementation of B2B order and delivery systems. For accurate and easy understanding of the user's requirements I have expressed my specifications in graphical method and to make use of multiple diagrams, I have used UML. In these specifications, I have implemented B2B order and delivery systems with the use of XML, with company 'N' which is domestic aluminum manufacturer as the study object. The results of this study are as follows. First, both a developer and a user can understand the problems associated with specifying study objects through this system. Second, the communication between developers and users is more effective using this system. Third programming became easier because or the formalized specifications of this system. Fourth, this system facilitates the rapid handling of marketing department and stock management. Fifth, order and reservation management became more rapid and accurate through the use of this system. Sixth, this system can help nate B2B order and delivery systems that can be direct transactions. Seventh, this system helps to reduce purchasing costs by allowing for the rapid and simple order and delivery of raw materials. Finally, this study emphasized the advertising effect of an aluminum vessel.