• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.535-541
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• 2020

FCAW is used mainly in the welding of carbon steel and alloy steel because it can be welded in all positions and can obtain excellent quality at sites with variable working conditions. Recently, many studies in Korea have estimated the fatigue strength, residual stress, and deformation, and to develop a fillet welding process. On the other hand, there have been few studies of the mechanical properties based on the strength, macro and magnetic particle test results for fillet welding. This study shows the following results through fillet welding, macro testing and strength testing using SM490A (solid-structure rolled steel) for thick plates using SS400 (rolled steel) for the upper plate and FCAW. The hardness test, macro test and magnetic particle test were then conducted. The hardness tests showed that all result values were smaller than the KS B 0893 standard values of 350Hv. The macro-test showed that each type of welded part was in a normal organic state and that there were no internal errors, bubbles, or impurities on the front of the welded part. Therefore, there were no concerns about lamination. The magnetic particle examination showed no problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.32-38
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• 2020

This study summarizes test methods and evaluation methods for examining the thermal characteristics of Jeju-type ground heat exchangers (GHXs) installed on Jeju Island, and analyzes the ground temperature and thermal characteristics of ground heat exchangers installed in various regions by using thermal response tests (TRT). Jeju Island is composed of volcanic rock layers, and the groundwater flow is well developed. A Jeju-type GHX can be installed up to 30 m from groundwater level after drilling a borehole. The ground heat exchanger has a structure in which several pipes are inserted into the borehole. In order to examine the characteristics of the Jeju-type GHX, tests were conducted on ground heat exchangers installed in four places on Jeju Island (Pyoseon, Jeju, Namwon, and Hallym). As a result of the analysis of the Jeju-type ground heat exchanger, the ground circulating water temperature stabilized according to the heat injection, depending on the installed location, and was formed within one to three hours. The ground heat exchanger capacity in Hallym was highest at 73.4 kW (cooling) and 82.8 kW (heating), and the Jeju-type calculation was lowest at 34.1 kW (cooling) and 23.3 kW (heating).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.638-644
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• 2020

This study examines cracks that occur under the load of an aircraft. The life of aircraft vulnerability structures was analyzed and structural fitting improvements were made. Structural integrity and safety have been achieved through preemptive life expectancy and life management of aircraft structures. The crack size inspection capability of the aircraft under analysis is 0.03inch, compared with 0.032inch, which is the lowest of the three vulnerable parts. In addition, the fatigue life analysis results in approximately 1450 operating hours, the lowest of the three vulnerable parts relative to the aircraft's required life of more than 15000 operating hours, which increased the repeat count of the aircraft's initial and re-inspection times, and hence raised the resulting costs and manpower consumption. Finally, the features were improved through structural fitting of the identified three weak parts. The lowest critical crack size was secured at 0.13 through increased structural resistance to generated cracks and increased aircraft safety. The lowest structural fatigue life for cracks occurring during aircraft operation is 25000 operating hours, which are analyzed above the required structural life, resulting in more optimized improvements than the repair costs and excessive fitting range caused by cracks and fractures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.285-291
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• 2020

In manufacturing, humans are being replaced with robots, but expert skills remain difficult to convert to data, making them difficult to apply to industrial robots. One method is by visual motion recognition, but physical features may be judged differently depending on the image data. This study aimed to improve the accuracy of vision methods for estimating the posture of humans. Three OpenPose vision models were applied: MPII, COCO, and COCO+foot. To identify the effects of face-covering accessories and image preprocessing on the Convolutional Neural Network (CNN) structure, the presence/non-presence of accessories, image size, and filtering were set as the parameters affecting the identification of a human's posture. For each parameter, image data were applied to the three models, and the errors between the actual and predicted values, as well as the percentage correct keypoints (PCK), were calculated. The COCO+foot model showed the lowest sensitivity to all three parameters. A <50% (from 3024×4032 to 1512×2016 pixels) reduction in image size was considered acceptable. Emboss filtering, in combination with MPII, provided the best results (reduced error of <60 pixels).

• Journal of Korean Medical classics
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• v.3
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• pp.280-398
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• 1989

The most distintive features on the Thinking Structure of the Views of the Nature and the Theories of the Medicine of the ancient Chinese are a Comprehensions to the System of the Nature which reveals in the Natural Phenomena. Nothing doesn't changed in the Nature and man also. These Changes are inevitable to the man. So it isn't easy to grasp the Essence of the Natural Phenomena which always be changed. I-Ching (易經, Book of Changes), Chung-Yung (中庸) and many other books are that has a theories about the Changes, the ancients could recognized the unchangeable constancy from the ever changeable Natural Phenomena. The unchangeable constancy on the Oriental thinking means as same as an 'Idea' on the Western thinking. These process made them shape up the Views of the Nature and the Medical theories. And Chi (氣), Yin-Yang (陰陽) and Wu-Hsing (五行) are the most important concepts of their views and theories. In the concepts of Chi as an epistemological meaning; the Nature and the Han can be appreciated as a one System, because his being is within the Changes of the Nature and should be in accord with those Changes. He was going to believe that all beings are exist as an existential rules of himself. So Chi can be thougt as an epistemological system to all beings' existence. Thinking of Yin-Yang as a existential meaning; all beings are exist having a contrary and a complementary to each other. Birth and Death, Be ginning and Finishing in a series of the process occurs in all beings are the two sides of their existential and intrinsic tendencies. That can be condensed to the Yin-Yang concepts. In the consideration of Wu-Hsing;all beings are observed and explained more deliberatively by it's own rules. By the way the concepts of Chi, Yin-Yang and Wu-Hsing which derived from the processes of the recognition to the Changes of the Nature are practiced actually by the thoughts of Harmony. And it is represented by the accordance to the Time of the Natural Changes, that is, Shiling (時令). It means a adjustments to the Time and Changes of the Nature. The health of all beings that is an aim of the Medicine can be maintained by their practical thoughts or the concepts of Shiling.

• The Journal of the Korea Contents Association
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• v.8 no.3
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• pp.234-243
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• 2008

The aim of this study was to provide the way of activation plans of leisure activities for older people through the current status and problems in welfare center for the elderly in Korea. Various social phenomena and issues have been found to occur in rapidly social-structure changes and urban civilization. Especially, processing an aging society for no preparation is one of the broader question of our country. Developing the scientific and civilization lengthening our span of life is given more leisure time than past. Unfortunately, older people could not independently stand for in their leisure, if society does not support for them. It means that they might feel the enough time to monotone life, depression and a sense of alienation. The following ideas would be expressed to the way of activation plans of elderly leisure. First, the elderly leisure facilities for leisure and publicity activities should be supplemented or strengthened. Second simple entertainment-oriented programs in the physical and psychology learning to adapt for them should be obtained through leisure activities for older people. Third, more senior recreation specialists or therapists should be educated for leisure activities. Fourth, the concept of leisure in older people's idea should be changed through the education. Fifth, people who work in the welfare center for the elderly should develop the leisure programs or activities for older people. Last the new culture of leisure concept should be constructed in our society between the two and three generation for sharing and participating the leisure.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.257-265
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• 2010

The purpose of this study was to investigate the effect of different ramp inclination on the maximum plantar foot pressure and pathway of the center of pressure. Fifteen healthy adults who had no musculoskeletal disorders were participated with this study and descended the ramp with different inclination(level, $-5^{\circ}$, $-10^{\circ}$, $-15^{\circ}$). Plantar foot pressures were recorded by the Matscan system(Tekscan, Boston, USA) during level and descending ramp with barefoot. Plantar foot surface was defined as seven regions for pressure measurement; two toe regions, three forefoot regions, one midfoot region, one heel region. Repeated ANOVA was used to compare each region data of foot according to different ramp inclination. As descending ramp inclination became increased, the pressure of hallux region was significantly increased at $-15^{\circ}$ inclination and the pressure of 2-3 metatasal head region were significantly decreased at $-5^{\circ}$, $-10^{\circ}$, $-15^{\circ}$ inclination. The pathway of COP had a tendency to be shifted inside in forefoot and prolonged to great toe as the descending ramp inclination increased. The results indicated that plantar foot pressure could be changed at hallux and forefoot regions with $-5^{\circ}$ ramp inclination and these findings demonstrated that ramp inclination could affect the structure and function of foot.

• The Journal of the Korea Contents Association
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• v.14 no.2
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• pp.48-59
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• 2014

This study examines the characteristics in melodramas by comparing three major television broadcasting companies(MBC, SBS, and KBS) since 2000. The findings of the study are as follows: "Romance" melodrama is more common in MBC and SBS, than in KBS, where "family" melodrama is more common. The most cause of conflict shown in MBC is "love between the rich and the poor" that in SBS is "conflict between love and success", and that in KBS is the conflict similar to that between "Ondal the fool and Princess Pyeong-gang". The most common love relationship shown in SBS and KBS is the "single love triangle" and that in MBC is "double love triangle". In the shows of all three TV broadcasting companies, male protagonists most frequently belongs to "jaebeol" (the rich) and female protagonists are "company workers". The most common personality trait of male protagonists' in MBC shows is and "optimism", in SBS shows, it is "supercilious behavior", in KBS, it is "simple-hearted". However, the personality of female protagonists in the shows of all three broadcasting companies can be described as, bright and cheerful. In MBC and SBS, male protagonists were frequently portrayed as capable, and in KBS, as self-conceited. in KBS are the most frequent. Female protagonists in the shows of all three broadcasting companies were most frequently portrayed as hardworking.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.3
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• pp.85-90
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• 2006

The purpose of this research is to design an imitation boiler similar to the waste heat boiler installed on a plasma melting furnace in order to acquire a capability of a thermal design as to the circulation of heat and the discharge of noxious gas inside a boiler and to improve the efficiency of a waste heat boiler using the CFD (Computation Fluid Dynamics) program. The position of corrosion and the generation of a clinker inside a boiler due to temperature changes, combustion gas flows, and corrosive gases inside a boiler are examined to design the structure of an efficient boiler and recycle energy. As a result of this research, the boiler installed on a plasma melting furnace met the conditions of design by cooling the combustion gases discharged after the second combustion from an exhaust port, originally at 1,200 degrees Celsius, down to around 450 degrees Celsius. On the other hand, the circulation of corrosive gases (SOx and HCL) may lead to the generation of corrosion or a clinker in the upper and lower parts of an exhaust port more easily than any other parts of a boiler. Accordingly, the corrosion on the inside and outside walls of a boiler may result in a shortened lifespan of a boiler and an inability to recycle waste heat in an efficient manner. A prevention against corrosion at high and low temperatures needs to be considered in detail.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1269-1275
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• 2006

The selection of multienzyme complex-producing bacteria under aerobic condition was conducted for improving the degradation of lignocellulosic substances. The criteria for selection were cellulase and xylanase enzyme production, the presence of cellulose-binding domains and/or xylan-binding domains in enzymes to bind to insoluble substances, the adhesion of bacterial cells to insoluble substances, and the production of multiple cellulases and xylanases in a form of a high molecular weight complex. Among the six Bacillus strains, isolated from various sources and deposited in our laboratory, Paenibacillus curdlanolyticus B-6 strain was the best producer of cellulase and xylanase enzymes, which have both cellulose-binding factors (CBFs) and xylan-binding factors (XBFs). Moreover, multiple carboxymethyl cellulases (CMCases) and xylanases were produced by the strain B-6. The zymograms analysis showed at least 9 types of xylanases and 6 types of CMCases associated in a protein band of xylanase and cellulase with high molecular weight. These cells also enabled to adhere to both avicel and insoluble xylan, which were analyzed by scanning electron microscopy. The results indicated that the strain B-6 produced the multienzyme complex, which may be cellulosome or xylanosome. Thus, P. curdlanolyticus B-6 was selected to study the role and interaction between the enzymes and their substrates and the cooperation of multiple enzymes to enhance the hydrolysis due to the complex structure for efficient cellulases and xylanases degradation of insoluble polysaccharides.