• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.24 no.3
• /
• pp.179-188
• /
• 2012

Performance analyses of vertical breakwaters were conducted for fictitiously designed breakwaters for various water depths to analyze the influence of climate change on the structures. The performance-based design method considering sea level rise and wave height increase due to climate change was used for the performance analysis. One of the problems of the performance-based design method is the large calculation time of wave transformation. To overcome this problem, the SWAN model combined with artificial neural network was used. The significant wave height and principal wave direction at the breakwater site are quickly calculated by using a trained neural network with inputs of deepwater significant wave height and principal wave direction, and tidal level. In general, structural stability becomes low due to climate change impacts, but the trend of stability is different depending on water depth. Outside surf zone, the influence of wave height increase becomes more significant, while that of sea level rise becomes negligible, as water depth increases. Inside surf zone, the influence of both wave height increase and sea level rise diminishes as water depth decreases, but the influence of wave height increase is greater than that of sea level rise. Reinforcement and maintenance policies for vertical breakwaters should be established with consideration of these results.

• Journal of Korean Society of Steel Construction
• /
• v.19 no.1
• /
• pp.29-41
• /
• 2007

Structural design, like other complex decision problems, involves many trade-offs among competing criteria. Although mathematical programming models are becoming increasingly realistic, they often have design limitations, that is, there are often relevant issues that cannot be easily captured. From the understanding of these limitations, a decision-support system is developed that can generate some useful alternatives as well as a single optimum value in the optimization of steel frame structures. The alternatives produced using this system are "good" with respect to modeled objectives, and yet are "different," and are often better, with respect to interesting objectives not present in the model. In this study, we created a decision-support system for designing the most cost-effective moment-resisting steel frame structures for resisting lateral loads without compromising overall stability. The proposed approach considers the cost of steel products and the cost of connections within the design process. This system makes use of an optimization formulation, which was modified to generate alternatives of optimum value, which is the result of the trade-off between the number of moment connections and total cost. This trade-off was achieved by reducing the number of moment connections and rearranging them, using the combination of analysis based on the LRFD code and optimization scheme based on genetic algorithms. To evaluate the usefulness of this system, the alternatives were examined with respect to various design aspects.

• Journal of Preventive Medicine and Public Health
• /
• v.36 no.2
• /
• pp.153-162
• /
• 2003

Objective : This study was conducted in order to investigate professional job perception, job stress and job satisfaction in doctors. Method : The authors conducted a survey using a self-administered questionnaire, conducted between August and September,2001. The study subjects were 457 doctors practicing at local clinics in Daegu City. Results : For the professionalism scale, the score for 'sense of calling to field' and 'feeling of autonomy' were relatively high, Age, working hours per day, and perception of socioeconomic status significantly influenced the professionalism scale scores (p<0.01). For the job stress scale, the scores for 'clinical responsibility/decision' factor were the highest of all the surveyed factors. Working hours per day significantly influenced the job stress scores (p<0.01). To investigate the overall relationship between the variables, the authors conducted a linear structural equation model analysis. The equation was statistically appropriate and a good fit. The job stress, and the professionalism factors, respectively influenced job satisfaction negatively and positively (T>2.0). The working hours per day and status perception also influenced their job satisfaction (T>2.0). Conclusion : To promote the iob satisfaction of doctors, the development of coping tools and other intervention methods are needed to increase doctor's professional job perception and reduce their job stress. Further studies are required to understand the characteristics of job satisfaction and for its promotion with doctors.

• Journal of Technology Innovation
• /
• v.23 no.1
• /
• pp.61-86
• /
• 2015

This study provides an empirical analysis based on 2012 Korea Innovation Survey (STEPI) to investigate the relation between R&D cooperation and in-house R&D investment. The study further analyzes the effect of the R&D cooperation and in-house R&D investment on technical innovation. First, the relation between company's in-house R&D investment and R&D cooperations is estimated with the two equations using SUR models. Second, the effect of in-house R&D investment and R&D cooperation on the company's technical innovation is estimated using Probit model. This study differs from other existing R&D studies using Korean data in that empirical models are based on structural relationships among in-house R&D, R&D cooperation, and technical innovation. The results can be summarized as follows; the R&D cooperation expands the in-house R&D investment and the in-house R&D strengthen the R&D cooperation. Furthermore, In-house R&D investment increases the chances of success in innovation. As we obtain evidence of complementary relation between R&D cooperation and in-house R&D investment, it is necessary to develop environment conducive to this complementarity in order to have more efficient R&D system.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.4
• /
• pp.500-511
• /
• 2016

This study examined the effects of the physical functions (ADL, IADL), mental functions (CES-D, MMSE-K) and oral health impact profile (OHIP-14) on the quality of life (WHOQOL-BREF) of the elderly in long-term care facilities. The study subjects were 602 elderly people, who were surveyed at the entrance to the long-term care facilities. The interviews were conducted using a questionnaire during the period from May 1, to June 30, 2014. As a result, the quality of life was affected more by the CES-D and MMSE-K than by the ADL and IADL or by OHIP-14; the quality of life improved with a higher ADL, IADL, and OHIP-14 and a higher CES-D and MMSE-K. A higher OHIP-14, ADL and IADL resulted in a higher CES-D and MMSE-K. These results suggested that the quality of life is correlated significantly with the physical functions (ADL, IADL), mental functions (CES-D, MMSE-K), and the oral health impact profile (OHIP-14).

• Journal of Biomedical Engineering Research
• /
• v.24 no.5
• /
• pp.427-434
• /
• 2003

In this paper, we present a speech-based Environmental Control System(ECS) and its application. In the concrete, an ECS using the speech recognition and an portable wheelchair lift control system with the speech synthesis are developed through the simulation and the embodiment. The developed system apply to quadriplegic man and we evaluate the result of physical effect and of mental effect. Speech recognition system is constructed by real time modules using HMM model. For the clinical application of the device, we investigate the result applied to 54-years old quadriplegic man during a week through the questionnaires of Beck Depression Inventory and of Activity Pattern Indicator. Also the motor drive control system of potable wheelchair lift is implemented and the mechanical durability is tested by structural analysis. Speech recognition rate results in over 95% through the experiment. The result of the questionnaires shows higher satisfaction and lower nursing loads. In addition, the depression tendency of the subject were decreased. The potable wheelchair lift shows good fatigue life-cycle as the material supporting the upper wheelchair and shows the centroid mobility of safety. In this paper we present an example of ECS which consists of real-time speech recognition system and potable wheelchair lift. Also the experiments shows needs of the ECS for korean environments. This study will be the base of a commercial use.

• Journal of Internet Computing and Services
• /
• v.20 no.6
• /
• pp.85-93
• /
• 2019

Computational Science and Engineering is a convergence study that understands and solves complex problems such as science, engineering, and social phenomena through modeling using computing resources. Computational science and engineering combines algorithms, computational and informatics, and infrastructure. The importance of computational science is increasing with the improvement of computer performance and the development of large data processing technology. In Korea, Korea Institute of Science and Technology Information (KISTI) has been developing national computational science engineering software and utilization technology by combining basic science and computing technology through EDISON project. The EDISON project builds an open EDISON platform and integrates and services information systems in seven areas of computational science and engineering (computational thermal fluids, nanophysics, computational chemistry, structural dynamics, computational design, and computational medicine). Using this, we have established a web-based curriculum to lay the groundwork for fostering scientific talent and commercializing computational science and engineering software. The purpose of this study is to derive the quality characteristic factors of computational science platform and to empirically examine the effect on user satisfaction. This paper examines how the quality characteristics of information systems, the computational science engineering platform, affect the user satisfaction by modifying the research questions according to the propensity of the computational science platform by referring to the success factors of DeLone and McLean's information system. Based on the results of this study, we will suggest strategic implications for platform improvement by searching the priority of quality characteristics of computational science platform.

• Journal of Digital Convergence
• /
• v.14 no.4
• /
• pp.89-100
• /
• 2016

The present study aims at investigating the effects of the Korean language ability, social support and acculturative stress of migrant laborers on hope and life satisfaction. The results of structural equation model showed that the social support and acculturative stress of migrant laborers influences life satisfaction through hope. The Korean ability of these laborers was intermediate level where they performed well in reading while they showed low performance in speaking and listening. The results of the study are as follows. First, hope mediates the effects of Korean ability on life satisfaction and does the effects of social support and acculturative stress on life satisfaction. Second the results that the better they hope the bigger life satisfaction gets implied that hope is the immediate cause of life satisfaction. Third, for their hope, we should provide not only language education but also opportunities for the perception that the role of family and neighbors is important. It is also necessary to facilitate active movements with the local community so that the migrant laborers take part in roles as members of society. Further we need to operate lifelong education programs for helping the migrant labores to adapt their lives in Korea.

• Journal of the Korea Institute of Building Construction
• /
• v.13 no.2
• /
• pp.181-192
• /
• 2013

Given both structural safety and economic benefits of aging facilities, remodelling of the existing facilities is preferable to reconstruction. This recognition provides an opportunity to reduce the commitment of resources and national budget. However, when a subordinate troop asks for remodeling or reconstruction of a deteriorated facility, it is difficult to ensure the consistency and objectivity in the process of decision making for the alternatives due to the absence of systematic and quantitative rating methodology. Their economic evaluation methodology only exists in a manual format. Thus, further research is required for converting the methodology into an automated system in view of practicality such as rapid and accurate data processing. The contributions of this study are as follows: 1) Literature review found out a representative economic evaluation model focused on military facilities, and comparative analysis with a similar study identified the strength and weakness. 2) this study presented how to convert the theoretical framework which enables to solve a specific subject matter into an automated system. 3) it developed a user friendly interfaces which consist of four functional modules by considering the usability and accessibility of the system user. 4) the developed system was verified by a case study in terms of four kinds of performance indicators.

• Korean Journal of Construction Engineering and Management
• /
• v.13 no.1
• /
• pp.95-105
• /
• 2012

The government introduced the technical proposal drafting system in September 2007, as a new method to stimulate technical competence among construction companies to require ingenuity, creativity, artistic sense, and high-level technology. However, an examination of instances has shown that this system has been applied only to large scale constructions worth 30 billion won or more, and not to small and medium constructions worth less than 30 billion won. This is because the evaluation criteria of the system is structured in a manner that makes it difficult to apply to small and medium constructions. This study presented methods to improve the evaluation factors, categories, and scoring scheme of the technical proposal creation system for medium to small scale constructions to be able to further apply the current system to small and medium constructions. The technical proposal evaluation criteria presented in this study was significant in that it enabled the technical proposal creation system that was mainly used for large scale constructions to be further applied to medium to small scale constructions. And it also contributes to the establishment and settlement of a new technical proposal tendering for medium to small scale constructions.