• Journal of Korean Association for Spatial Structures
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• v.11 no.1
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• pp.57-66
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• 2011

For the lateral load resistance of a RC frame in a medium risk seismic zone, the strength of lower story beams and columns should be larger than those of the upper stories. However, the lateral loads can be accommodated by redistributing design beam moments vertically as well as horizontally so all beams end up with identical strengths. This paper looks at the impact of the vertical redistribution of beam moments to provide identical beam strength over as many floors as possible. Two-bay six-story RC frame was designed with and without vertical beam moment redistribution and its seismic performance were evaluated by using push-over limit analysis and by non-linear time history dynamic analysis. Analytical results show that with the use of vertical beam moment redistribution the increase in the ductility demand is similar to the proportion of moment redistribution applied, but this additional demand is below the ductility capacity of well detailed RC members.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.62-69
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• 2013

Visual demands associated with in-vehicle display usage and text messaging distract a driver's visual attention from the roadway. To minimize eyes-off-the-road demands, voice interaction systems are widely introduced. Under cognitively distracted condition, however, awareness of the operating environment will be degraded although the driver remains oriented to the roadway. It is also know that the risk of inattentive driving varies with age, thus systematic analysis of driving risks is required for the older drivers. This paper aims to understand the age-related driving performance degradation and visual attention changes under auditory cognitive demand which consists of three graded levels of cognitive complexity. In this study, two groups, aged 25-35 and 60-69, engaged in a delayed auditory recall task, so called N-back task, while driving a simulated highway. Comparisons of younger and older drivers' driving performance including mean speed, speed variability and standard deviation of lane position, and gaze dispersion changes, which consist of x-axis and y-axis of visual attention, were conducted. As a result, it was observed that gaze dispersion decreased with each level of demand, demonstrating that these indices can correctly rank order cognitive workload. Moreover, gaze dispersion change patterns were quite consistent in younger and older age groups. Effects were also observed on driving performance measures, but they were subtle, nonlinear, and did not effectively differentiate the levels of cognitive workload.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.3
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• pp.651-656
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• 2017

Virtual Training generates virtual situation or environment with specific goals in order to instruct trainees as if they are in the real-world. Recently, the demand of experiencing certain incident, which we are not able to experience in real life, has been increased along with the fast developing Virtual Reality (VR) technology. Particularly, Virtual Training(VT) enables us to learn various fields those require high risk and high cost. The system of VT provides interaction and allows us absorb these learning materials better which augments learning effect. Based on the demand of Virtual Training system, this research analyzes current education paradigm National Competency Standards (NCS) in Korea and suggests possible education that utilizes Virtual Training system. At the end of the day, our future goal is to apply suggested Virtual Training contents to universities that reflect NCS curriculum like polytechnic university.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.93-101
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• 2015

The demand from customers on better products and systems seems to be ever increasing. To meet the demand, the systems are becoming more and more complicated in terms of both scale and functionality, thereby requiring enormous effort in the development. One bright spot of this trend is that such effort has been the driving forces of the remarkable advancement in modern systems development. On the other hand, safety issues appear to be critical in many large-scale systems such as transportation and weapon systems including high-speed trains, airplanes, ships, missiles/rockets launchers, and so on. Such systems turn out to be prone to a variety of faults and thus the resultant failure can cause disastrous accidents. For the reason, they can be referred to as safety-critical systems. The systems failure can be attributed to either random or systemic factors (or sometimes both). The objective of this paper is on how to reduce potential systemic failure in safety critical systems. To do so, a proper system design is pursued to minimize the risk of systemic failure. A focus is placed on the fact that complex systems have a lot of complicated interfaces among the system elements. To effectively handle the sources of hazards at the complicated interfaces and resultant failure, a method is developed by utilizing a design structure matrix. As a case study, the developed method is applied in the design of train control systems.

• The Journal of Society for e-Business Studies
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• v.20 no.2
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• pp.93-106
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• 2015

Providing trading partners with personal information to establish an e-commerce financial transaction is inevitable. Most e-commerce companies keep personal information and transaction data for user's convenience and develop additional services as their applications. However, keeping personal information increases the likelihood of identity theft causing direct or indirect damage while it may simplify repetitive financial transactions. This study introduces risk management methods based on quantitative and qualitative analysis including demand-supply curve model and Gordon & Loeb model to analyze the risks for security management. The empirical analysis with survey results from KISA (Korea Information Security Agency) shows that the root cause of different statistics of personal information leakage incidents according to core business of internet companies is the difference in their Loss Expectancy caused by them. Also we suggest disciplinary compensation and higher standard for personal information protection as a solution to prevent the variation of investment on it between individual companies.

• STI Policy Review
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• v.5 no.1
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• pp.75-97
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• 2014

Entrepreneurial financing, such as publicly initiated venture capital or grant schemes, serves as an important policy instrument that aims to bridge the financing gap facing young, innovative businesses, a gap that is mainly due to higher risk and growing uncertainty, and to strategically promote the creation of new ventures through the revitalization of their venture capital industries. This study examines public venture capital initiatives in Australia, Canada, and Sweden, and discovered that all three countries actively foster their venture capital industry through the formation of funds or the provision of tax incentives. It is notable that the majority of financing initiatives heavily depend on supply-side measures rather than demand-driven policies that focus on stimulating private investment in technological innovations and discoveries. This paper discusses in-depth the policy impact of public financing initiatives and their subsequent side-effects raised in the process such as overlapping in funding structure across the country, lack of monitoring and evaluation for feedback, fragmentation across the government ministries and agencies, and competition with the private sector, which may cause inefficiency as a result of public intervention. Financial constraints may arise for many reasons, partly resulting from the lack of investment readiness of young entrepreneurs. This signals a policy shift towards the creation of market-driven demand away from the traditional supply-push approach, and is a grand challenge to policymakers in entrepreneurial financing. Attention is leaning towards the efficiency and effectiveness of these public-financing initiatives in terms of their policy roles. It is worth noting that policy should focus on generating synergy so available resources can be channeled into the early, risky stage of new ventures, working as facilitator to the achievement of an intended policy goal.

• Journal of Korean Academy of Nursing
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• v.40 no.5
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• pp.650-661
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• 2010

Purpose: Work-related anxiety and depression are frequent work-related mental health problems. In this study the relationship between workplace violence and work-related anxiety and/or depression among Korean employees was evaluated. Methods: Data were obtained from the Korean Working Condition Survey of 2006. Participants were 9,094 Korean workers aged 15-64 yr. Multiple logistic regression using SAS version 9.1 was used. Results: The incidence of work-related anxiety, work-related depression and workplace violence were 4.5%, 3.5%, and 1.8% respectively. When personal and occupational risk factors were adjusted, workplace violence was significantly associated with work-related anxiety and depression (OR for anxiety: 4.07, CI: 2.62-6.34; OR for depression: 4.60, CI: 2.92-7.25). Work-related anxiety was significantly related to type of employment, working period at present workplace, work time, shift work, job demand, and social support from superiors. Factors influencing work-related depression were gender, education, alcohol consumption, company size, type of employment, working period at present workplace, work time, shift work, and job demand. Conclusion: To promote psychological health in workers there is a need to develop work-related anxiety and depression prevention programs and to decrease in workplace violence. In developing these programs, consideration should be given to personal factors, working conditions, and psychosocial working environments.

• Anxiety and mood
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• v.16 no.1
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• pp.24-31
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• 2020

Objective : The purpose of our study was to investigate the relationship between job stress and depressive disorder among emotional laborers in a city. Methods : A total of 677 emotional laborers living in Jeonju-city participated in this study. The participants completed survey questions regarding demographic characteristics, job stress (using the Korean Occupational Stress Scale-24, KOSS-24), and depression (the Patient Health Questionnaire-9, PHQ-9). Logistic regression was performed to estimate the association between job stress and depression. Results : Our results indicated that 34.9% of the participants had a high risk of total job stress and 21.7% of participants had depression. In the multivariate logistic regression analysis, female sex (OR=1.66, 95% CI=1.01-2.72) and total job stress (OR=3.84, 95% CI=2.57-5.75) were significantly associated with depression after adjusting for confounding factors. Among the subscales of job stress, job demand (OR=3.06, 95% CI=1.99-4.72) and occupational climate (OR=1.88, 95% CI=1.19-2.97) were significantly associated with depression. But insufficient job control, interpersonal conflict, job insecurity, the organizational system and lack of rewards were not. Conclusion : Among the emotional laborers, job stress, particularly job demand and occupational climate, were major contributing factors associated with depression. Early screening and preventive strategies focusing on job stress could reduce the impact of depression in emotional laborers.

• Journal of Energy Engineering
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• v.26 no.4
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• pp.7-13
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• 2017

As environmental problems become a problem of survival, interest in eco-friendly energy is increasing to improve the environment. So, demand for eco-friendly fuels such as hydrogen, LPG and CNG is increasing. In particular, Korea, which relies on imports of most fuels, is investing in the development of hydrogen energy, which is favorable in terms of high production volume and energy independence. However, As demand grows every year, a variety of accidents occur in various ways, ranging from small leak incidents to massive fires and explosion, thus research needs to be done. So, in this study, compared and analyzed cases of hydrogen, LPG, CNG accidents occurring at domestic and overseas refueling stations. and various programs were used for assessing risk, estimated the flame length due to gas leakage and evaluated the dangerous distance.

• Proceedings of the Technology Innovation Conference
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• 2005.02a
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• pp.124-139
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• 2005

In the early stage, the radio communication industry was widely accepted as a monopoly industry, so it has been controled and managed by government. But the advanced technology in Information and Technology industry has led constant increase of demand and dramatic change of communication market. Furthermore it is expected that frequency resource is to be short by market change due to wire-wireless integration. That is why the effort to utilize and manage limited frequency resource efficiently is being executed around the world. Not only newly developing and allocating the spectrum but also reallocating the existing spectrum important are, since transforming inefficiently used existing spectrum to new service can increase producer's surplus and social welfare. The economic approach to valuate the spectrum and spectrum usage right is necessary different from the traditional cost based approach, and through this approach I expect active transaction of spectrum. In this paper the real option methodology is used for valuation of spectrum, considering spectrum user's option right based on future revenue. In detail, the matter of withdrawing and reallocating the existing analog radio broadcasting spectrum is evaluated in this paper, The digitalization of a broadcasting service is widely spreaded around the world in terms of technology and service utility, and analog TV broadcasting has already been decided to be transformed to digital TV broadcasting. It was planned to convert analog radio broadcasting to DAB service before adopting DMB service, but nowadays this issue is not on the table anymore. However if the increasing demand of digital voice and broadcasting service is considered, this kind of research to valuate a spectrum is needed urgently. The result of this research shows that when the redeployment of spectrum is done, social welfare will increases. The point of the reallocation time and value are suggested by the monte carlo simulation through ROVM. In this paper, I use real option to valuate the spectrum and provide the point of the reallocation time and reasonable guideline, and moreover, the suitable information of this paper is expected to reduce risk and loss in policy practice.