• Transactions of the Korean hydrogen and new energy society
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• v.26 no.6
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• pp.638-644
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• 2015

This paper describes the continuing effort to analysis and design on dynamic and electrical behavior of gamma-type free piston Stirling engine/generator with dual-opposed linear generator for domestic micro-CHP (Combined Heat and Power) system. The double acting Stirling engine/generator has one displacer and two power piston which are supported by flexure springs. Two power pistons oscillate with symmetric sinusoidal displacement and are connected with moving magnet type linear generators for power generation. To operate Stirling engine/generator, combustion heat of natural gas is supplied to hot-end and heat is rejected from cold-end by cooling water. The temperature difference across the displacer induces the oscillating motion, and it can be explained with mass-spring vibration system. The purpose of this paper is to describe the design process of linear generator for the double acting free-piston Stirling engine.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.241-247
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• 2015

In an effort to discover alternative phytotherapeutic antimicrobial agents to combat Streptococcus parauberis, a fish pathogenic bacterium, we evaluated the antibacterial activity of seaweed extracts in vitro. A methanolic extract of Ecklonia cava exhibited strong antibacterial activity against S. parauberis isolated from olive flounder Paralichthys olivaceus. Furthermore, the n-hexane soluble (Hexane) fraction of the E. cava methanolic extract exhibited the greatest antibacterial effect on S. parauberis strains with a minimum inhibitory concentration (MIC) ranging from 256 to $1,024{\mu}g/mL$. In addition, the MIC values of oxytetracycline against antibiotic-resistant S. parauberis were markedly reduced up to 64-fold in combination with the Hexane fraction, suggesting that the antibacterial activity of the antibiotic was restored when combined with the Hexane fraction. The interaction between both antibiotics and the Hexane fraction was assessed by the fractional inhibitory concentration (FIC) index. The Hexane fraction and oxytetracycline combination against antibiotic-resistant S. parauberis strains resulted in a median ${\sum}FIC$ range of 0.502 to 0.516. Thus, the synergistic ranges of median ${\sum}FIC$ < 1 were observed for all combinations of the Hexane fraction and oxytetracycline against S. parauberis. To the best of our knowledge, this is the first report indicating the efficacy of an E. cava extract against fish pathogenic bacterium S. parauberis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3658-3665
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• 2010

As the population of elderly people and disabled people are increased, various demands for human welfare using robot system are raised. Especially autonomous rehabilitation system using robot could reduce the human effort while maintaining the its intrinsic efficacy. This study deals with mobile gait rehabilitation system which combined with BWS (Body Weight Support) for training of elderly and handicapped people who suffer the muscle force weakness of lower extremity. BWS which is designed by kinematic analysis of body lifting characteristics and walking guide system are integrated with main control system and wheeled platform. This mobile platform is operated by UCS (User Command System) and autonomous trajectory planning algorithm. Finally, through the EMG (Electromyography) signal measuring and its analysis for subject, performance and feasibility of developed system is verified.

• Journal of Chest Surgery
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• v.20 no.1
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• pp.81-91
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• 1987

During the period of 10 years from July, 1976 to July, 1986, 154 cases of primary carcinoma of the lung - by the cell type, stage, operability, and survival rate in the resectable cases - are analyzed at the Dept. of Thoracic Surgery, Paik Hospital in Seoul. The results are as follows: 1] Histopathological types are squamous cell carcinoma 49% [76 cases], adenocarcinoma 25% [39 cases], undifferentiated large cell carcinoma 9% [14 cases], undifferentiated small cell carcinoma 6% [9 cases], bronchioloalveolar carcinoma 4% [6 cases] and adenosquamous carcinoma 3% [4 cases]. 2] Peak incidence is observed in the 4th decade of life [33%], then 5th [29%] and 3rd [21%] respectively. Male to female ratio is 4 to 1. 3] Evidence of inoperability is observed in 64% [99 cases] by clinical staging workup. Thirty six percent [55 cases] were operated. Of these, post-surgical stage I was 5% [3 cases], stage II, 64% [35 cases] and stage III, 31% [17 cases]. Among total 17 cases of stage III, 14 cases were unresectable with evidence of T2N2M0, while 3 cases were resectable. Resectability is 27%, [41 cases] from the total number of 154 cases. And the resectability for the ex 55 cases is 75% [41 cases]. 4] By cell type, highest resectabitity is the squamous cell carcinoma, 49% [20 cases]. Adenocarcinoma is 32% [13 cases] and bronchioloalveolar, 12% [5 cases]. 5] Survival rate is evaluated for 38 cases of 41 resectable stage I, II and III. Overall 5 year survival rate is 24%, 3 year 32% and 10 year 8%. Survival rate in stage II for 5 year is 25%. In squamous cell type for, 5 year is 42%. Authors believe when surgeons continuous effort of early detection is met with patients early visit, 5 year survival rate for the stage I K II resectable patients will improve more effectively. As well, When the efforts are added to combined modality with radiotherapy and chemotherapy for the stage III selected cases of non-small cell carcinoma patients, the enhancement in survival rate is expected.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.400-411
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• 1999

The purpose of this study was to identify the physical exercise and the effects of exercise on health. Data were collected from Oct. to Dec. 1998. The subjects were 241 middle aged women living in Seoul and near Seoul. The following instruments were used in the study: The questionniare for physical exercise and health status was combined with simple CMI and climacteric symptom. Analysis of the data was done by chi-test. t-test. and ANOVA with SAS program. The results of this study were as follows: 1. The rate of physical exercise was 59.3% of subjects. The mean number of exercise per week was 3.1. Duration at one time exercise was 25.6 minutes. The period of exercise was 18.6 months. And main objective of exercise was health promotion. 2. The physical exercise had differences according to the age. job. monthly income. period of marriage. type of family. and perceived body image. 3. Musculoskeletal and mental complaints were lower in no-exercise group than exercise group(respectively P=0.04. 0.02). According to the duration of exercise. autonomous nervous symptoms was the lowest in 20 minutes group(P=0.04) and psychologic complaints was the lowest in below 60 minutes group(P=0.03). According to the period of exercise. cardiovascular and fatigue complaints was the lowest in 7-12 months maintenance group and autonomous nervous complaint was the lowest in below 3 months maintenance group(P=0.04). This study is only a preliminary effort. so I recommend that the repeated studies be carried out including detailed. comprehensive exercise practice and developing systematic exercise program.

• Korean Institute of Interior Design Journal
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• v.19 no.6
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• pp.121-128
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• 2010

Interior design education has been developed rapidly since the discipline established in Korea in 1980s but unfortunately the development was without any progressive transition until 1990's. When Korean Institute of Interior Design/KIID inaugurated in 1992, interior design education and related research activities began to be intensified. Despite its effort, there were still confusion about the discipline as there were many similar discipline tracks (architecture, design, fine art, & home economic, etc.) each having an own definition of interior design and introducing different aspects of educating the subject. Education program for interior design still not sufficiently supporting the needs of today's rapidly changing industry nor to prepare the diverse needs of the client. In order for interior design major to be effective in the future and fulfill the needs of current industry development within our society, re-evaluation of our current interior design educational programs in Korea is important. This study will be the beginning of a research series. As the first part of the research series, this particular study has been focused on reviewing of current status of interior design majors in the nation and its current condition. While making suggestion for the changes in curriculum, the following points will have to be considered as basic principle. First, understanding the duality of technology and design to accommodate the contents of design discipline. Second, understanding the need of practice and theory combined for practical education. And lastly, considering ways to adopt the human experience in order to develop creativity in oneself. The focus of this research is only on the interior design discipline, and research method as the following; first, analyze current status by reviewing admission data for 2010. Second, process a survey regarding the interior design education and practice-related issues in admissions and collect opinions from educators and professional designers in the field. Thirdly, with reference to previous studies, suggestions will be made for the discipline to be effective in the field. As mentioned earlier, this study series will continue and develop to suggest improvement in interior design program as well as to provide curriculums for students get ready for the industry with more up-to-date knowledges and creativities.

• Korea and Global Affairs
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• v.1 no.1
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• pp.97-114
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• 2017

This article aims for searching the clue of North Korea nuke-problem by understanding it contextually. We must see this from the beginning as many trials in settling the problem have failed. North Korea nuke-problem is related to the change of international implication as well as the domestic process of its development. At first, it started from the regime survival, which evolved with the effect of learning. During the Cold War, its development had combined the principle of 'self-defense' because of Sino-Russia conflict. Particularly, its meaning varied dramatically due to the collapse of Cold War system plus the advent of post-Cold War system. North Korea nuclear program has became a global problem based on the deterioration of North Korea's security milieu and Bush administration's policy. Therefore, the area of common solution for NK nuke-problem must be found in the context of regime survival and the change of its meaning by continual convergence effort.

• Geomechanics and Engineering
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• v.3 no.1
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• pp.61-81
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• 2011

In this paper, a complement to the Hoek-Brown criterion is proposed in order to derive the strength of anisotropic rock from strength of the corresponding truly intact rock. The complement is a decay function, which unlike other modifications or suggestions made in the past, is multiplied to the function of the original Hoek-Brown failure criterion for intact rock. This results in a combined and extended form of the criterion which describes the strength of anisotropic rock as a varying fraction of the corresponding truly intact rock strength. Statistical procedures and in particular regression analyses were conducted into data obtained in experiments conducted in the current research program and those collected from the literature in order to define the Hoek-Brown's criterion complement. The complement function was best described by a simple polynomial including only three constants to be empirically evaluated. Further investigations also showed that these constants can be related to the other readily available parameters of rock material which further facilitate determining the constants. A great and prime advantage of the proposed complement is that it is mathematically simple including the least possible number of empirical constants which are easily estimated with minimum experimental effort. Moreover, proposed concept does not suggests any change to the original Hoek-Brown criterion itself or its constants and serves whenever anisotropy does exist in the rock. This further implies on the possibility of using any other failure criterion for intact rock in conjunction with the compliment to reach the strength of anisotropic rock.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2007.05a
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• pp.190-191
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• 2007

Cleanout of the F Reactor Fuel Storage Basin (FSB) is an element of the FSB decontamination and decommissioning (D&D) and is required to complete interim safe storage (ISS) of the F Reactor. Following reactor shutdown and in preparation for a deactivation layaway action in 1970, the water level in the FReactor FSB was reduced to approximately 0.6 m (2 ft) over t]to floor. Basin components and other miscellaneous items were left or placed in the FSB. The item placement was performed with a sense of finality, and no attempt was made to place the items in an orderly manner. The F Reactor FSB was then filled to grade level with 6(20of local surface material (essentially a fine sand). The reactor FSB backfill cleanout has the potential of having to remove spent nuclear fuel (SNF) that may have been left unintentionally. Based on previous cleanout of six water-filled FSBs with similar designs (i.e., the B, C, D, and DR FSBs in the 1980's), it was estimated that up to five SNF elements could be discovered in the F FSB (I). In reality about 17 full SNF elements were found in the excavation. This paper covers the technical and programmatic challenges of performing this decommissioning effort with some of the controls used for SNF management. The paper also will highlight how many various technologies were married into a complete package to address the issue at hand and show how no one tools could complete the job, but combined, good progress is being made.

• Journal of Convergence Society for SMB
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• v.2 no.1
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• pp.11-18
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• 2012

As scale of software has been expanded and complicated, it is difficult to detect hazards which induce functional failure of software. Functional failure of safety-critical system (nuclear power plant, air traffic control systems, railway operating system) could result in a disaster (personal injury, environmental pollution). Therefore, it is necessary to conduct a safety analysis for preventing functional failure and increasing safety of the software. However, there are some reasons (time and effort problem, low knowledge of various safety analysis techniques, selecting conventional technique in company, organization) which disturb selecting an apposite one. This paper presents some traditional safety analysis techniques, recently presented techniques and combined models. We expect that it helps stakeholders to choice adequate one for target system.