• Journal of the Korean Society of Systems Engineering
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• v.15 no.2
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• pp.98-107
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• 2019

The defense system development process is a process of developing various systems that perform functions in various functional areas such as battlefield awareness, command control, force application, and logistical support. In other words, the defense system development process is a process of developing many systems simultaneously in various functional areas. Various systems developed through this process should be interoperable so that they can be integrated and operated in a joint warfighting environment. To successfully implement this, the US Department of Defense uses the Joint Capability Integrated Development System(JCIDS) for the defense system development, and within this JCIDS processes the Capability Based Assessment(CBA) methodology as its core technology. This CBA methodology transforms the mission activity requirements to functional capability requirements logically and transforms the functional capability requirements to system requirements logically also. Smart City is a city that improves the convenience and quality of life of the citizen by integrates various systems that perform various functions of the city and smarties various functional systems with smart services by using IT technology. In other words, defense system development and smart city development have a common feature of the process of developing many systems simultaneously in various functional areas. In order to address the problem of having to develop many systems simultaneously in each functional area, it is important to logically transform the various mission scenarios into functions and logically transform the functions into systems. Therefore, a joint capability integrated development system and its core methodology, Capability Based Assessment(CBA), can be applied to smart city development. This paper proposes a method for performing a smart city concept design method using the capability based evaluation (CBA) method.

• Journal of computational fluids engineering
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• v.20 no.1
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• pp.84-91
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• 2015

SMART adopts, very unique facility, an FMHA to enhance the thermal and flow mixing capability in abnormal conditions of some steam generators or reactor coolant pumps. The FMHA is important for enhancing thermal mixing of the core inlet flow during a transient and even during accidents, and thus it is essential that the thermal mixing characteristics of flow of the FMHA be understood. Investigations for the mixing characteristics of the FMHA had been performed by using experimental and CFD methods in KAERI. In this study, the temperature distribution at the core inlet region is investigated for several abnormal conditions of steam generators using the commercial code, FLUENT 12. Simulations are carried out with two kinds of FMHA shapes, different mesh resolutions, turbulence models, and steam generator conditions. The CFD results show that the temperature deviation at the core inlet reduces greatly for all turbulence models and steam generator conditions tested here, and the effect of mesh refinement on the temperature distribution at the core inlet is negligible. Even though the uniformity of FMHA outlet hole flow increases the thermal mixing, the temperature deviation at the core inlet is within an acceptable range. We numerically confirmed that the FMHA applied in SMART has an excellent mixing capability and all simulation cases tested here satisfies the design requirement for FMHA thermal mixing capability.

• Management & Information Systems Review
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• v.19
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• pp.145-170
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• 2006

The purpose of this study is to examine the relationship between core factor of Knowledge Management(KM) and organizational effectiveness. The objects of study are middle manager in hosing construction and civil engineering and construction industry, and the sample size is 228. The core factor of KM and indicator of organizational effectiveness are drawn by literature survey. The core factors are classified into human capital, organizational capital, structural capital, (to put it concretely), job capability, human relation, strategy, information technology, process, sharing culture, leadership, measurement. The indicator of organizational effectiveness are measured by job satisfaction, organization loyalty, competitiveness. The main results of this study can be summarized as the following. 1) The core factor of KM has a positive relationship to organizational effectiveness. Especially, the core factor of sharing culture and leadership are strongly relationship with organizational effectiveness. 2) There was a high positive correlation between job satisfaction and organization loyalty. 3) Human, structural, and structural capital had a different affect on organizational effectiveness. 4) The more job position and educational level high, the more they recognized that KM is necessary for their organization. 5) Among the success factor in KM, the factor of job capability was well perceived to respondent. According to this study, we can analyzed the relationship between success factor and organizational effectiveness, and drawn the most influence success factor on organizational effectiveness. Concurrently, the results of this study will be useful guidelines for shaping the KM operation framework in construction industry.

• Journal of Korean society of Dental Hygiene
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• v.16 no.3
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• pp.337-346
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• 2016

Objectives: This study aims to investigate and analyzed the priority of vocational core competency factors in dental hygienists in Gwangju. Methods: Expert survey was conducted and Analytic Hierarchy Process(AHP) was applied to evaluate the weighting factors. First, we established the vocational core competency defined in NCS as AHP analysis model. The vocational core competency has 10 categories and 34 sub-categories. Secondly, AHP survey was conducted by 195 dental hygienists in Gwangju. Finally, the weights representing relative importance of each factor were calculated by using AHP method. Results: The AHP analysis on 10 categories showed that the weighting of interpersonal skills(0.165) was higher than any other categories while that of numeracy(0.035) was at the bottom, and the analysis on sub-categories revealed that the most important factors in each categories included the teamwork skills(interpersonal skills), problem-solving capability(problem-solving skills), listening skills(communication skills), ethical community(professional ethics), ability to understand business(ability to understand organizational structure), applicable technical skills(technical skills), self-management skills(self-development capability), information processing capabilities(information capacity), ability to manage time(resource management capabilities) and basic math skills(numeracy). Conclusions: The results in this study can be used as basic data for the development of liberal arts curriculum for dental hygiene education.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.97-106
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• 2018

Improved load-following capability is one of the most important technical tasks of a pressurized water reactor. Controlling the nuclear reactor core during load-following operation leads to some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking: the core is subjected to sharp and large variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent the core power peaking. One of the important local power peaking components in nuclear reactors is axial power peaking, which continuously changes. The main challenge of nuclear reactor control during load-following operation is to maintain the AO within acceptable limits, at a certain reference target value. This article proposes a new robust approach to AO control of pressurized water reactors during load-following operation. This method uses robust feedback-linearization control based on the multipoint kinetics reactor model (neutronic and thermal-hydraulic). In this model, the reactor core is divided into four nodes along the reactor axis. Simulation results show that this method improves the reactor load-following capability in the presence of parameter uncertainty and disturbances and can use optimum control rod groups to maneuver with variable overlapping.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2438-2446
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• 2023

To cool down a nuclear reactor core and prevent the fuel damage without a pump-driven active component during any anticipated accident, the passive emergency core cooling system (PECCS) was designed and adopted in an advanced light water reactor, i-POWER. In this study, for a validation of the cooling capability of PECCS, thermal-hydraulic integral effect tests were performed with the ATLAS facility by simulating intermediate and small break loss-of-coolant accidents (IBLOCA and SBLOCA). The test result showed that PECCS could effectively depressurize the reactor coolant system by supplying the safety injection water from the safety injection tanks (SITs). The result pointed out that the safety injection from IRWST should have been activated earlier to inhibit the excessive core heat-up. The sequence of the PECCS injection and the major thermal hydraulic transient during the SBLOCA transient was similar to the result of the IBLOCA test with the equivalent PECCS condition. The test data can be used to evaluate the capability of thermal hydraulic safety analysis codes in predicting IBLOCA and SBLOCA transients under an operation of passive safety system.

• Nuclear Engineering and Technology
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• v.31 no.5
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• pp.476-485
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• 1999

In order to evaluate the gravity-injection capability to maintain core cooling after a loss-of-shutdown-cooling event during shutdown operation, the plant conditions of the Yong Gwang Units 3&4 were reviewed. The six cases of possible gravity-injection paths from the refueling water tank (RWT) were identified and the thermal-hydraulic analyses were performed using the RELAP5/MOD3.2 code. The core cooling capability was significantly dependent on the gravity-injection path, the RCS opening, and the injection rate. In the cases with the pressurizer manway opening higher than the RWT water level, the coolant was held up in the pressurizer and the system pressure continued increasing after gravity-injection. The gravity injection eventually stopped due to the high system pressure and the core was uncovered. In the cases with the injection path and opening on the same leg side, the core cooling was dependent on whether the water injected from the RWT passed the core region or not. However, in the cases with the injection path and opening on the different leg side, the system was well depressurized after gravity-injection and the core boiling was successfully prevented for a long-term transient. In addition, from the sensitivity study on the gravity-injection flow rate, it was found that about 54 kg/s of injection rate was required to maintain the core cooling and the core cooling could be provided for about 10.6 hours after event with that injection rate from the RWT. Those analysis results would provide useful information to operators coping with the event.

• Journal of the Korea Institute of Military Science and Technology
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• v.6 no.3
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• pp.22-35
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• 2003

This paper describes system technical requirement development process from operational concept using computer-aided Systems Engineering tool(CASysE Tool-CORE). The army tactical missile system-ATACMS's technical requirements are developed by the process as a case-study The scope of the work is context analysis and requirement definition process. The proposed process is as follows. At first, an integrated architecture could be developed from the operational concept. From the integrated architecture a capability needs, which includes KPPs, are generated. And the capability needs expanded according to the Mil-Std-961D format. Lastly, a system technical requirement could be generated automatically from the CASysE Tool-CORE.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.968-976
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• 2019

This paper presents a number of verification case studies for a recently developed sensitivity/uncertainty code package. The code package, ROMUSE (Reduced Order Modeling based Uncertainty/Sensitivity Estimator) is an effort to provide an analysis tool to be used in conjunction with reactor core simulators, in particular the Virtual Environment for Reactor Applications (VERA) core simulator. ROMUSE has been written in C++ and is currently capable of performing various types of parameter perturbations and associated sensitivity analysis, uncertainty quantification, surrogate model construction and subspace analysis. The current version 2.0 has the capability to interface with the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA) code, which gives ROMUSE access to the various algorithms implemented within DAKOTA, most importantly model calibration. The verification study is performed via two basic problems and two reactor physics models. The first problem is used to verify the ROMUSE single physics gradient-based range finding algorithm capability using an abstract quadratic model. The second problem is the Brusselator problem, which is a coupled problem representative of multi-physics problems. This problem is used to test the capability of constructing surrogates via ROMUSE-DAKOTA. Finally, light water reactor pin cell and sodium-cooled fast reactor fuel assembly problems are simulated via SCALE 6.1 to test ROMUSE capability for uncertainty quantification and sensitivity analysis purposes.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1291-1295
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• 1999

Modern functional languages provide some forms of pattern matching capability in them. However, these forms are on an ad-hoc basis and vary from languages to languages, making the user hard to understand the feature. To overcome this problem, we present a systematic approach to adding pattern matching to functional language. We extend to the core functional language with pattern matching capability and illustrate several examples of the language. We also discuss how to extend the pattern matching capability to higher-order terms.