• Journal of the Korea Safety Management & Science
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• v.9 no.6
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• pp.105-112
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• 2007

The era of express train in Korea has come since April in 2004. The KTX(Korea Train Express) which has introduced the technology of TGV of France is regraded as good as the ICE of Germany or Shinkansen of Japanese in its hardware aspects. However there are still many things to be improved in its software aspects such as the quality of services, since the new express railway system is in the early beginning stage. To improve the quality of services, we should first measure and analyze the current level of the service quality. Using SERVQUAL model, the service level of KTX is measured and analyzed in this paper. Issues on how to improve the service quality are discussed based on the measurement and analysis.

• Journal of Power System Engineering
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• v.11 no.1
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• pp.45-50
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• 2007

Acoustic emission technology is applied to diagnosis the internal leak and operating conditions of the major valves at nuclear power plants. The purpose of this study is to verify availability of the acoustic emission as in-situ diagnosis method. In this study, acoustic emission tests are performed when the pressurized high temperature steam flowed through gate valve(1st stage reheater valve) and glove valve(main steam dump valve) on the normal size of 4 and 8". The valve internal leak diagnosis system for practical field was designed. The acoustic emission method was applied to the valves at the site, and the background noise was measured for the abnormal plant condition. To improve the reliability, a judgment of leak on the system was used various factors which are AE parameters, trend analysis, signal level analysis and RMS(root mean square) analysis of acoustic signal emitted from the valve operating condition internal leak.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.249-265
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• 2006

A life cycle assessment(LCA) is increasing its applicability as a powerful tool for an environmental burdens analysis. In this study, some cases are compared in terms of analysis procedures and results obtained with LCAs for evaluating power generation technologies in Korea. For the comparison, 3 power generation technologies are selected because they produces almost 90% of 2003 total electricity generation in Korea. It is shown that the range of evaluation values amounts to maximally the order of about 105, which is rather large discrepancy than the level of 101 in comparison with foreign studies. The difference seems to be due to the simplicity of modeling used in each case study. It is proposed that this large discrepancy should be obviously clarified to improve their reliability in that electricity is a essentialness for all industries and the capacity of LCA of national-level electricity affects the results of LCA for the other sectors.

• Journal of Information Processing Systems
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• v.10 no.4
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• pp.568-580
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• 2014

To enhance the utilization of the traffic channels of a network (instead of allocating radio channel to an individual user), a channel or a group of channels are allocated to a user group. The idea behind this is the statistical distribution of traffic arrival rates and the service time for an individual user or a group of users. In this paper, we derive the blocking probability and throughput of a subscriber station of Worldwide Interoperability for Microwave Access (WiMAX) by considering both the connection level and packet-level traffic under a complete partition scheme. The main contribution of the paper is to incorporate the traffic shaping scheme onto the incoming turbulent traffic. Hence, we have also analyzed the impact of the drain rate of the buffer on the blocking probability and throughput.

• Nuclear Engineering and Technology
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• v.34 no.4
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• pp.331-343
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• 2002

We performed an importance analysis of In-Service Testing (157) components for Ulchin Unit 3 using the integrated evaluation method for categorizing component safety significance developed in this study. The developed method is basically aimed at having a PSA expert perform an importance analysis using PSA and its related information. The importance analysis using the developed method is initiated by ranking the component importance using quantitative PSA information. The importance analysis of the IST components not modeled in the PSA is performed through the engineering judgment, based on the expertise of PSA, and the quantitative and qualitative information for the 157 components. The PSA scope for importance analysis includes not only Level 1 and 2 internal PSA but also Level 1 external and shutdown/low power operation PSA. The importance analysis results of valves show that 167 (26.55%) of the 629 IST valves are HSSCs and 462 (73.45%) are LSSCs. Those of pumps also show that 28 (70%)of the 40157 pumps are HSSCs and 12 (30%) are LSSCs.

• Nuclear Engineering and Technology
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• v.34 no.1
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• pp.90-103
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• 2002

The thermal and mechanical properties of compacted bentonite and bentonite-sand mixture were collected from the literatures and compiled. The thermal conductivity of bentonite is found to increase almost linearly with increasing dry density and water content of the bentonite. The specific heat can also be expressed as a function of water ontent, and the coefficient of thermal expansion is almost independent on the dry density. The logarithm of unconfined compressive strength and Young’s modulus of elasticity increase linearly with increasing dry density, and in the case of constant dry density, it can be fitted to a second order polynomial of water content. Also the unconfined compressive strength and Young’s modulus of elasticity of the bentonite-sand mixture decreases with increasing sand content. The Poisson’s ratio remains constant at the dry density higher than 1.6 Mg/m$_3$, and the shear strength increases with increasing dry density.

• Journal of Korea Society of Digital Industry and Information Management
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• v.15 no.2
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• pp.53-61
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• 2019

In this paper, we propose 'a self - conformance system of convergence security provider' to provide basic data for security and reliability of convergence industrial technology, system and service. It is difficult to evaluate convergence security systems, limited to information and communication service providers, unable to check convergence security items, burden of submission documents, difficulty in measuring convergence security service level and we will summarize product and service-based requirements that can be integrated and systematically measure the level of convergence security and define renewed life cycle-based convergence security information and content security and assurance requirements. On the basis of this, each convergence security company declares conformity with the standard itself without the certification of the certification body, and introduces the provider conformity certification system which can manufacture and sell. This will enable the company to strengthen its competitiveness through timely launch and implementation of products and services and cost reduction.

• Journal of Convergence for Information Technology
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• v.10 no.3
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• pp.48-57
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• 2020

This study focuses on the development of simple qualitative indicators for evaluating and selecting innovation leading companies that challenge National Award. Another purpose of this study is to complement the aspect in which the innovative or value of the companies' products, technologies, and services is only quantitatively evaluated. Existing evaluation indicators of national award have too many evaluation items and were not suitable for innovation-based company evaluation. The research approach is to select category for developing qualitative indicators based on previous studies and TF discussion. From the input-process-output-outcome point of view, we have set up an indicator system as a series of flows. Finally, five categories such as creativity, system excellence, customer value, performance, and ripple effects are selected as qualitative indicator. For these selected indicators, conceptual definitions and the main points of evaluation are described. And the system level evaluation and the ADLI approach are presented for reference. The appendix also includes examples of qualitative and quantitative evaluation of real companies using these indicators. However, this study implies the possibility that the evaluation results may vary depending on the level and perspective of the evaluator. We hoped that detailed research on candidate indicators that can be used as qualitative indicators and research on the development of mixed indicators(qualitative and quantitative) will continue in the future.

• Journal of Information Technology Application
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• v.2 no.1
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• pp.139-160
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• 2000

This paper suggests a technique for evaluating cognitive process when a working group performs its group tasks. First, it review a theory of distributed cognition which provides a theoretical background for investigating group's cognitive process. Then, it presents a procedure for DGOMS(Distributed GOMS) evaluation which is an extension from GOMS. GOMS is an analytica evalutation technique that has been used at the individual level. DGOMS analyzes task completion time and compares workload among group members on the basis of each member's task execution time, communication time, and cognitive workload. DGOMS can be applied to a situation where a group of people are working together for a common goal using a technical subsystem such as information systems.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.3
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• pp.73-85
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• 2005

Natural disturbance and environmental pressure on natural ecosystems are gradually increasing, and the cause is significantly related to large-scale environmental pollution, global warming, decreasing biodiversity and habitat fragmentation. Environmental impact assessment(EIA) in Korea has been focused on distribution and composition of fauna and flora as major evaluation aspects in ecosystem assessment. It is well known that those characteristics of flora and fauna strongly depend on characteristics and quality of habitat and ecosystem. However, there is no items to assess habitat and ecosystems of spatial ecological system in EIA. Many countries are trying to develop the EIA items to consider the spatial characteristics of habitat and ecosystem and those ecological dynamics as well as species level. In this stream, landscape ecology is emerging discipline to examine spatial pattern and ecological process within/between habitats and ecosystems. Landscape ecological analysis, as a special tool for ecosystem evaluation, has been appropriately adopted to the EIA system in the advanced countries. This review paper tries to introducing the possibilities of landscape ecological concept into the Korean EIA system.