• Earthquakes and Structures
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• v.19 no.4
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• pp.261-272
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• 2020

Recent severe earthquakes in and around the vital public places worldwide indicate the severe vulnerability of ground excitation to be assailed. Reducing the effect of seismic lateral load in structural design is an important conception. Essentially, seismic isolation is required to shield the superstructure in such a way that the building superstructure would not move when the ground is shaking. This study explores the effectiveness, design, and practical feasibility of base isolation systems to reduce seismic demands on buildings of varying elevations. Thus, static and dynamic analyses were conducted based on site-specific bi-directional earthquakes for base-isolated as well as fixed-based buildings. Remarkably, it was discovered that isolators used in low-rise to high-rise structures tend to significantly decrease the structural responses of seismic prone buildings. The higher allowable horizontal displacement induces structural flexibility and ensure good structural health of the building stories. Reinforcement from vertical and horizontal members can be reduced in significant amounts for BI buildings. Thus, although incorporating base isolators increases the initial outlay, it considerably diminishes the total structural cost.

• The Korean Journal of Rehabilitation Nursing
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• v.20 no.1
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• pp.42-51
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• 2017

Purpose: In people who have chronic diseases, disabilities, and rehabilitation needs, self-management education can improve health and health-related behavior, and it can reduce the utilization of healthcare services. The purpose of this research was to assess the long-term effects of chronic-disease self-management education in Japan. Methods: This study included 184 adults living with various chronic medical conditions who participated in the Chronic Disease Self-Management Program (CDSMP) in Japan. Data were collected before the program began, and then collected 3 more times over 1 year. Results: Healthcare-service utilization was low at baseline, and it did not change. Self-evaluated health status, health-related distress, coping with symptoms, communication with doctors, and self-efficacy to manage symptoms all improved after the program. However, there was backsliding in all of the outcomes that had improved. Conclusion: Some benefits of this program can last for at least 1 year, but interventions to prevent attenuation may be needed. For economic evaluations, research should focus on populations with higher baseline levels healthcare-service utilization, including use of rehabilitation services. Also, more attention should be focused on the longer-term decay or persistence of the program's benefits, particularly regarding on preventing and reducing disabilities and with regard to rehabilitation needs.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.67-70
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• 2007

It is well known that the aircraft engine inlet should be safely designed against the bird strike at the aircraft development stage. The aircraft accident is increasing for FOD(Foreign Object Damage), especially bird of runway circumference. The aircraft accident due to bird strike brings about economic loss and which is connected with the life of passengers. In this study, MSC/DYTRAN has been utilized to analyze the aircraft engine inlet against the bird strike. In order to validate the proposed method for the bird strike analysis, this study was performed with comparison of precedence study results.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.315-322
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• 2015

The research carried out on thorium-based fuels indicates that these fuels can be considered as economic alternatives with improved physical properties and proliferation resistance issues. In the current study, neutronic assessment of $UO_2$ in comparison with two $(Th-^{233}U)O_2$, and $(Th-^{235}U)O_2$ thorium-based fuel loads in a heavy water research reactor has been proposed. The obtained computational data showed both thorium-based fuels caused less negative temperature reactivity coefficients for the modeled research reactor in comparison with $UO_2$ fuel loading. By contrast, $^{235}U$-containing thorium-based fuel and $^{235}U$-containing thorium-based fuel loadings in the thermal core did not drastically reduce the effective delayed neutron fractions and delayed neutron fractions compared to $UO_2$ fuel. A provided higher conversion factor and lower transuranic production in the research core fed by the thorium-based fuels make the fuel favorable in achieving higher cycle length and less dangerous and costly nuclear disposals.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.657-660
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• 2013

The Internet is referred as sea of information, which provides huge information, but personal information is collected for malicious behavior and provided to various web sites via internet. This can lead to economic losses as well as the disclosure of personal information. We can easily get personal information from device, such as mobile and private terminal, as well as internet, and then it can be spread very quickly. The personal information leakage and damage cases are also increasing, while the importance of personal information on the web page to distinguish the individual as the basic information is growing. In this paper we review and analyse recent invasion of privacy practices on the web and its causes, and technical and administrative protections.

• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.697-708
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• 2012

The majority of instrumentation and control (I&C) systems in today's nuclear power plants (NPPs) are based on analog technology. Thus, most existing I&C systems now face obsolescence problems. Existing NPPs have difficulty in repairing and replacing devices and boards during maintenance because manufacturers no longer produce the analog devices and boards used in the implemented I&C systems. Therefore, existing NPPs are replacing the obsolete analog I&C systems with advanced digital systems. New NPPs are also adopting digital I&C systems because the economic efficiencies and usability of the systems are higher than the analog I&C systems. Digital I&C systems are based on two technologies: a microprocessor based system in which software programs manage the required functions and a programmable logic device (PLD) based system in which programmable logic devices, such as field programmable gate arrays, manage the required functions. PLD based systems provide higher levels of performance compared with microprocessor based systems because PLD systems can process the data in parallel while microprocessor based systems process the data sequentially. In this research, a bistable trip logic in a reactor protection system (RPS) was developed using very high speed integrated circuits hardware description language (VHDL), which is a hardware description language used in electronic design to describe the behavior of the digital system. Functional verifications were also performed in order to verify that the bistable trip logic was designed correctly and satisfied the required specifications. For the functional verification, a random testing technique was adopted to generate test inputs for the bistable trip logic.

• Fire Science and Engineering
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• v.25 no.6
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• pp.156-167
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• 2011

The number of buildings is growing at a rapid pace in Korea. It is driven by significant economic improvements, the rapid population growth and urban centralization. Such being this case, some city are underway to building enlargement, Manhattanization. To Solve these problem and ensure the safety of live, fire Evacuation Simulation system is used for safe check of buildings. Forecasting an egress behavior in building fire is so important in order to construct a safe and reliable environment. But, currently most of the fire evacuation simulation system used in practice are foreign software that is not reflect korean conditions. Thus, This study focus on objectives that develop a fire evacuation system considering Korean Characteristics and create 3D space-based topology. so the system calculate evacuation path. This system developed as a result of research can be used by architectural designer in practice due to it is based 3D spatial information modeling.

• Korean Journal of Human Ecology
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• v.12 no.2
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• pp.225-236
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• 2003

The purposes of this study were to promote the consumer's recognition on the internet purchase of fashion products and to provide useful information which would help web-site plan design, product composition, and service of internet shopping mall. The subjects were consisted of 693 students who had experiences of the accesses to internet fashion shopping mills or experiences of purchasing through internet in Cheongju and Daejeon region. Data were analyzed by factor analysis, frequency, percentage, mean, standard deviation, t-test, ANOVA, and LSD. The Results were as follows: 1. Merit factors of the internet shopping were found to be shopping convenience and pursuit of product information. Whereas, demerit factors of the internet shopping to be complexity of order, delivery, functional and economic riskiness, and services. 2. Gender was the only factor differentiating the level of recognition toward the internet fashion shopping mall. And the level of recognition also showed significant differences according to period, time, purpose of access, type of shopping mall, purchase experience, and average purchase price.

• Korean Journal of Human Ecology
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• v.24 no.5
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• pp.701-712
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• 2015

This study analyses "Survey of Health and Behavior of Children and Adolescents" which is conducted by National Youth Policy Institute that investigated influential factors in difference between actual obesity and perceptional obesity. GLM (Generalized Linear Mode) was carried out to estimate the effects on the eating habits and physical activities and multinomial logit analysis was carried out to examine the influential factors in difference between actual, obesity and perceptional obesity. The results of this study are shown as follows. First 72.0% of total respondents showed the congruence between actual obesity and perceptional obesity and 24.6% of total respondents perceived them fatter than actual. The remaining 3.5% perceived them thinner than actual. Second, the main effects of actual obesity and perceptional obesity on eating habits were statistically significant, but interaction effect between them was not statistically significant. The main effects of actual obesity and perceptional obesity on physical activities and interaction effect between them were all statistically significant. Third, the influential factors in difference between actual obesity and perceptional obesity were gender, age, school record, education of parents, subjective economic status, and living together with family.

• Environmental and Resource Economics Review
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• v.10 no.2
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• pp.217-234
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• 2001

The use of district heating is expanding very rapidly in Korea. High population densities and the relatively cold winters make district heating an economically attractive option. About 8 percent of Korean houses are already using district heating and the government is seeking to aggressively expand this number. It has set a target of 15 percent of the residential heat market to be met by district heating in the year 2001. The main purpose of this paper is to analyze the consumption behavior of households using district heating. By pooling time-series and cross-sectional data for 12 apartment complexes in Seoul area, a single demand function is estimated and used to forecast the amounts of heat demanded by the individual households. The results shows that the level of consumption varies among households, depending on the non-economic factors such as the installation of individual metering equipment and the volume of apartment building. When individual metering equipment is installed, the level of annual heat consumption per household declines, on average, about 22.1 Mcal per square meters, which is equivalent to 834 won per square meter in terms of heating expenditures. In case that the apartment building was built in more than 6 stories, annual consumption level reduces additionally about 17.3 Mcal per square meters and, thus, save the expenditures by 649 Won per square meters, compared to the opposite case.