• Nuclear Engineering and Technology
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• v.55 no.3
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• pp.1191-1198
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• 2023

Bentonite buffer material is a critical component in an engineered barrier system (EBS) for disposing high-level radioactive waste (HLW). The bentonite buffer material protects the disposal canister from groundwater penetration and releases decay heat to the surrounding rock mass; thus, it should possess high thermal conductivity, low hydraulic conductivity, and moderate swelling pressure to safely dispose the HLWs. Bentonite clay is a suitable buffer material because it satisfies the safety criteria. Several additives have been suggested as mixtures with bentonite to increase the thermal-hydraulic-mechanical-chemical (THMC) properties of bentonite buffer materials. Therefore, this study investigated the geotechnical, mineralogical, and THMC properties of several candidate additives such as sand, graphite, granite, and SiC powders. Datasets obtained in this study can be used to select adequate additives to improve the THMC properties of the buffer material.

• Journal of the Korean Society of Industry Convergence
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• v.21 no.5
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• pp.241-246
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• 2018

The engine cooling system is a device that keeps the temperature of the engine room at a proper level by driving the cooling fan when the engine room temperature that occurs during driving is above a certain temperature. Recently, the vehicle cooling system has been changed to electronic system. Therefore, in this paper, we will analyze the clutch operation characteristics for designing a superior electronic fan clutch. For this purpose, an electronic fan clutch was designed and a test bed for performance evaluation was constructed and analyzed.

• Journal of Industrial Technology
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• v.38 no.1
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• pp.21-27
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• 2018

In January 2018, the Ministry of Education published "Seismic design criteria for school buildings" and "Manual for seismic performance evaluation and retrofit of school buildings" to evaluate seismic performances through linear analysis. This paper evaluates the seismic performance of an old school building through the linear analysis. The target building was constructed in the late 1970s, and the seismic-force-resisting system was assumed to be a reinforced concrete moment frame with an un-reinforced masonry wall. As a result of the evaluation, the target building does not satisfy the 'life safety' level of 1.2 times the design spectrum. The average strength ratio of moment frames, an indicator of the level of seismic performance tends to be controlled by beams. However, through the Pohang earthquake, it was known that the short column effect caused by the partially infilled masonry wall caused shear failure of the columns in school buildings. Therefore, it is necessary to improve the linear analysis so that the column controls the average strength ratio of moment frames.

• Journal of Family Resource Management and Policy Review
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• v.11 no.4
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• pp.1-20
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• 2007

The purpose of this study was to identify the criteria of evaluating a price-comparison website, and to investigate the consumers' perceived importance and satisfaction of each criterion. Also, it compared both the importance and satisfaction levels based on consumers' socio-economic and Internet-usage characteristics. Data for this study came from a questionnaire completed by consumers (n=417), who had used the price-comparison website, and were analyzed through factor analysis, t-test, and ANOVA. The findings of the study were as follows: First, the evaluation criteria of the price-comparison website were categorized into five variety of information, accuracy, convenience, credibility, and the website system. Second, convenience of searching information was seen by consumers as both the most important and most satisfactory criterion. Variety of information was also considered important. For most of the evaluation criteria, the level of consumers' satisfaction was significantly lower than the level of consumers' recognized importance. Third, consumers in their 20s, students, and housewives were less likely to be satisfied by the price-comparison website overall. Older people were less likely to be satisfied with the convenience of the website, and the higher-income group was less likely to be satisfied with the variety of information on hand.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.761-772
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• 2009

The introduction of KTX (Korea Train eXpress) provided passengers with a much faster mode of transport, and KTX has become a model railway system. Express railway stations are emphasized as public transit transfer centers, but their service evaluations were not performed appropriately so far. It is possible to know the level of service by developing valuation criteria for their evaluations. The evaluation of transfer centers mainly consists of two parts; connective service with other travel m odes, and transfer service inside transfer stations. Connection is defined as the inter-connection of multi-transportation vehicles, and transfer means that a passenger changes his travel mode to another. Such connective service and transfer service are evaluated by the level of service in terms of transfer facilities, the appropriateness of station layout and the quality of information throughout the facilities. We developed the service evaluation indicators of connective facilities and referred to the indicators of transfer facilities. We examined the 7 stations in Korea that are currently in operation and standardized the methodology of the evaluation process by applying the indicators suggested in this study.

• Journal of Sensor Science and Technology
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• v.24 no.2
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• pp.96-100
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• 2015

In the present study, we developed a real-time radiation-monitoring sensor for an underwater radiation-monitoring system and evaluated its effectiveness using reference radiation sources. The monitoring sensor was designed and miniaturized using a silicon photomultiplier (SiPM) and a cerium-doped-gadolinium-aluminum-gallium-garnet (Ce:GAGG) scintillator, and an underwater wireless monitoring system was implemented by employing a remote Bluetooth communication module. An acrylic water tank and reference radiation sources ($^{137}Cs$, $^{90}Sr$) were used to evaluate the effectiveness of the monitoring sensor. The underwater monitoring sensor's detection response and efficiency for gamma rays and beta particles as well as the linearity of the response according to the gammaray intensity were verified through an evaluation. This evaluation is expected to contribute to the development of base technology for an underwater radiation-monitoring system.

• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.5
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• pp.30-34
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• 1981

This paper deals with the testability evaluation method for the digital systems. This method uses two factors: the complexity and the accessibility. The complexity depends on the ratio in combinational and sequential circuits, number of input/output terminals, and the circuit count by using the gate input level method. The accessibility is how easily to handle the data from I/O terminals. The system testability has a normalized value. Thus, analyzing the testability evaluation, and redesigning the circuit to improve testability, the systems increase interests for the maintenance and have high reliability. Finally, in comparison with Stephenson and Grason's technique, this technique gives sufficiently accurate results for much less computation effort.

• Journal of KIISE:Information Networking
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• v.31 no.2
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• pp.207-216
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• 2004

IPsec protocol has been developed to provide security services to Internet. Recently IPsec is implemented on the various operating systems Hence, it is very important to evaluate the stability of the Ipsec protocol as well as other protocols that provide security services. However, there has been little effort to develop the tools that require to evaluate the stability of IPsec protocols. Therefore, in this paper, we develope the security requirements and suggest a security evaluation system for the Internet packet protection protocols that provide security services at the If level that can be used to check if the security protocols Provide the claimed services correctly This system can be used as debugging tool for developing IPsec based security system.

• Journal of Energy Engineering
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• v.14 no.3 s.43
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• pp.167-172
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• 2005

This paper presents a methodology to support decision making for distribution system planning based on value. To evaluate the reliability value, we employ valued-based distribution reliability assessment. To evaluate the harmonics value, we employ a marginal pricing method, and by using reliability cost, harmonics cost, and construction cost, we can make the most economic decision. By applying the method to the real system, we show this method can get the best result which meet reliability and harmonics level.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.777-784
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• 2010

The purpose of this study was to develop evaluation indices for forest landscape classification. The indices were chosen to enable forest managers to establish effective landscape management strategies through three times of focus group interviews and email survey with experts. The 13 landscape evaluation indices were finally divided into four categories. They were ecological health (degree of green naturality, degree of ecological naturality, disease and insect damage, crown vitality), aesthetic visual quality (naturalness, harmony, diversity, traditionality, aesthetic appreciation, rarity), and sensitivity (level of tourism/recreational use), interruptions (damaged land, artificial structures). The five-level was suggested for the forest landscape classification system.