• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.06a
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• pp.297-305
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• 2002

The economic relevance of Web applications increases the importance of controlling and improving their quality. Moreover the new available technologies for the development allow the insertion of sophisticated funcations, but often leave the developers responsible for the organization and evolution. As a consequence, a high demand is emerging for methodologis and tools for quality assurance of Web based systems. In this paper, a UML model of Web applications is inroduced for their high level representation and concept of the verification and validation activities. In this paper proposed analysis algorithm that was based on Domestic Website and presented result through experiments.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.308-311
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• 2004

This paper describes design, implementation and functional test of on-board flight analog video system. Video system is the part of the telemetry system as a means of providing flight vehicle's image data. Adopting analog video transmission technique, we could design and test the system in a short time and implement the prototype model with simpler circuits. As results of the functional test, we have made the verification and validation of two cameras' switching in time, and frequency modulation and demodulation of NTSC color signals successfully.

• Journal of the Korean Society of Safety
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• v.26 no.6
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• pp.111-117
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• 2011

Risk-based railway safety management has been mandatory in Korea as by relevant laws and regulations enacted since the Railway Safety Act 2004. In particular, the Railway Vehicle Safety Guidance came into effect on Jan 1, 2008 specifies the details of methodology for hazard analysis, risk assessment and safety verification and validation. Fundamentals for success of the risk-based safety management are systematic hazard identification and risk assessment by use of reasonable risk assessment criteria, but the principle of risk-based safety management has not been applied in an effective way to introduction and maintenance of railway vehicle systems because definite risk assessment criteria have not been set down for each railway system or railway network. The purpose of this study is to suggest a risk matrix development principle for risk assessment of domestic urban metro vehicles by analyses of relevant rules and railway operating environment of Korea.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1058-1066
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• 2011

This research paper on Tac-ELINT SW development method using M&S system describes the validation and verification methods of Tac-ELINT ground operating software development each stages, and the method of improving reusability of software using SBD(Simulation Based Design/Development) concept. In this project, We obtain the EW software SBD technologies and improved Tac-ELINT ground operating software through software crisis mitigation. This method and technology will expect to support a future EW system and any other various weapon software development.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.6 s.123
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• pp.484-490
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• 2007

A reciprocating compressor used in domestic refrigerators can be subjected to many different forms of shock. These shocks are usually experienced during transporting the products from a manufacturer to customers. The hermetic structure of this kind of compressor makes it difficult to conduct drop tests for identifying the failure mechanism and their drop behaviors. The drop/impact simulation for a reciprocating compressor has been carried out with the explicit code LS-DYNA and its validation has been experimentally verified. Simulation results are in good agreement with those of drop test. The present method of drop/impact simulation provides an efficient and powerful solution to improve the design quality and reduce the design period.

• Nuclear Engineering and Technology
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• v.42 no.4
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• pp.365-376
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• 2010

This paper summarizes the results of a Writing Group on the Extension of CFD codes to two-phase flow safety problems, which was created by the Group for Analysis and Management of Accidents of the Nuclear Energy Agency' Committee on the Safety of Nuclear Installations (NEA-CSNI). Two-phase CFD used for safety investigations may predict small scale flow processes, which are not seen by system thermalhydraulic codes. However, the two-phase CFD models are not as mature as those in the single phase CFD and potential users need some guidance for proper application. In this paper, a classification of various modelling approaches is proposed. Then, a general multi-step methodology for using two-phase-CFD is explained, including a preliminary identification of flow processes, a model selection, and a verification and validation process. A list of 26 nuclear reactor safety issues that could benefit from investigations at the CFD scale is identified. Then, a few issues are analyzed in more detail, and a preliminary state-of-the-art is proposed and the remaining gaps in the existing approaches are identified. Finally, guidelines for users are proposed.

• Journal of computational fluids engineering
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• v.16 no.2
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• pp.30-48
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• 2011

A three-dimensional thermal-hydraulic code, CUPID, has been developed for the analysis of transient two-phase flows at component scale. The CUPID code adopts a two-fluid three-field model for two-phase flows. A semi-implicit two-step numerical method was developed to obtain numerical solutions on unstructured grids. This paper presents an overview of the CUPID code development and assessment strategy. The governing equations, physical models, numerical methods and their improvements, and the systematic verification and validation processes are discussed. The code couplings with a system code, MARS, and, a three-dimensional reactor kinetics code, MASTER, are also presented.

• Journal of Electrical Engineering and Technology
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• v.2 no.3
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• pp.386-390
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• 2007

At recent times, an essential issue in the replacement of the old analogue I&C to computer-based digital systems in nuclear power plants becomes the quantitative software reliability assessment. Software reliability models have been successfully applied to many industrial applications, but have the unfortunate drawback of requiring data from which one can formulate a model. Software that is developed for safety critical applications is frequently unable to produce such data for at least two reasons. First, the software is frequently one-of-a-kind, and second, it rarely fails. Safety critical software is normally expected to pass every unit test producing precious little failure data. The basic premise of the rare events approach is that well-tested software does not fail under normal routine and input signals, which means that failures must be triggered by unusual input data and computer states. The failure data found under the reasonable testing cases and testing time for these conditions should be considered for the quantitative reliability assessment. We presented the quantitative reliability assessment methodology of safety critical software for rare failure cases in this paper.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.29-37
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• 1994

It is reported that north Korea has already developed 1,500 to 2,000-km-range Scud missile. As a defensive strategy against Scud attack on military and civilian facilities the military authorities are considering deployment of Patriot missile. This paper deals with its optimal deployment strategy. In this problem a Patriot missile which has multiple-facility responsibility may be able to protect each of its assigned facilities only with a certain probability, not absolute protection, and it may not be adequate to have only a single missile protect a facility, either because of its operational reliability or because of its limited availability at any given point in time. We formulate this problem into the probabilistic partial set covering model developed by Sherali and Kim. The applicability, verification and validation of the model are tested via an abbreviated case study.

• ETRI Journal
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• v.17 no.3
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• pp.1-16
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• 1995

An advanced real-time satellite simulator (ARTSS) has been developed to support the ground operations activities of the ETRI satellite control system, such as testing of the system facilities, validation of flight control procedures, verification of satellite commands as well as training of the ground operators. The design of ARTSS is based on the top-down approach and makes use of a modular programming to ensure flexibility in modification and expansion of the system. Graphics-based monitoring and control facilities enhance the satellite simulation environment. The software spacecraft model in ARTSS simulates the characteristics of a geostationary communication satellite using a momentum bias three-axis stabilization control technique. The system can be also interfaced with a hardware payload subsystem such as Ku-band communication transponder to enhance the simulator capability. Therefore, ARTSS is a high fidelity satellite simulation tool that can be used on low-cost desk top computers. In this paper, we describe the design features, the simulation models and the real-time operating functions of the simulator.