• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.815-827
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• 2014

The current study was undertaken to verify appropriateness of muscle endurance test at three different angles ($30^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$) of isometric contraction position, and to sought valid and reliable testing method that provide an alternative to sit-ups. Total 92 young and healthy subjects (68 males and 24 females) were recruited, and the following results were obtained. 1. A low correlations in males, but a high correlations in females was found when the comparisons were made between aerobic and muscle endurance capability. 2. Measuring tolerance time, by using isometric contraction was showed a significant correlation with the repetition numbers of sit-ups. 3. The highest correlation was found at 40 inclined degrees of plane, and the lowest correlation was drawn from 50 inclined degrees of plane. Based on these results, it was concluded that measuring tolerance time during maintaining an isometric contraction at 40 inclined degrees of plane is a valid and effective tool for measuring abdominal muscle endurance, and it can be used as an alternative way of sit-up, which potentially risky for inducing many back-associated injuries. Further studies need to be undertaken to determine for optimal angles, that can safely be applied for people of various age groups and physical conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.625-631
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• 2014

In order to obtain a low evaporation temperature ranging from $-30^{\circ}C{\sim}-50^{\circ}C$, a cascade refrigeration system and two-stage compression one-stage expansion refrigeration system is required. However, the research results of performance comparison of these refrigeration system are very scarce. This paper were compared the performance characteristics of R744-R404A cascade refrigeration system and R404A two-stage compression refrigeration system. The COP of R404A two-stage compression refrigeration system is about 36~57% greater than that of R744-R404A cascade refrigeration system in the range of evaporation temperature of $-30^{\circ}C{\sim}-50^{\circ}C$. But R404A two-stage compression refrigeration system is unstable because COP is significantly changed when evaporating temperature and compressor efficiency decreased. In particular, when compressor efficiency decreased, COP is significantly decreased. In this case, not efficient for long-term use. Whereas R744-R404A cascade refrigeration system using natural refrigerants. Therefore, it is environmentally friendly. And this system is high-efficiency refrigeration system. The reason it can be configured by selecting the suitable refrigerant at high-temperature side and low-temperature side. From the above results, select the appropriate low temperature refrigeration system by considering the environmental and performance aspects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5214-5218
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• 2011

In this paper, bandwidth improvement of a series-fed two dipole array(STDA) antenna applicable for mobile communication base station antennas is studied. The proposed STDA antenna consists of two strip dipole antennas with different lengths which are connected directly trough a coplanar stripline(CPS). By adjusting the spacing between the two dipoles and the length of the second dipole, the bandwidth of the STDA can be enhanced. In addition, an integrated balun composed of a short-circuited microstrip line and a slot line is utilized to minimize the area required for a feeding part, and a broadband impedance matching is obtained by adjusting the feeding point. Based on the proposed antenna structure, an STDA antenna covering the frequency band ranging from 1.75 GHz to 2.7 GHz, which includes almost all the existing mobile communication frequency bands, with more than 5 dBi gain is designed and fabricated on an FR4 substrate with dielectric constant of 4.4 and thickness of 1.6mm, and experimentally tested. The fabricated antenna shows impedance bandwidth of 49%(1.7-2.8 GHz) for VSWR<2, a gain higher than 5.5 dBi, and a front-back ratio better than 12 dB.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2516-2522
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• 2009

The data which analyze the results of blood cultures are crucial basic information of the empirical therapy for patients with infection since the patterns of the species of microorganism isolated from blood and the results of antibiotic susceptibility test vary depending upon patients general features. Especially, in case of ESBL-producing bacteria, there is a close relation with use of antibiotics. Therefore, we carried out the research with the results of blood culture and antibiotic. 1. Total 39,305 cases of blood culture samples were investigated and positive patients of 2,216 (20.0%) were found. Among those, there were 40 patients with ESBL positive, and blood culture positive samples were 4,798 (12.2%). ESBL positive bacteria were found in 86 samples (including double checked culture bacteria). 2. The majority of ESBL producing bacteria were E. coli, K. pneumoniae and K. oxitoca as ordering based on the number. 3. The research showed the results that there were more females than male with the bacterias, more E. coli in over 50 years old aged group than other bacterias, more K. pneumoniae and K.oxitoca in less 1 year old aged group than other bacterias and largest numbers of patients with 13 patients (32.5%) in Chungcheongnam-do province were found. 4. The most common ESBL producing bacteria were E. coli throughout 3 years, but K, pneumoniae and K. oxitoca were also fairly found. Interestingly, E. coli was highly found in over 50 years old patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2396-2401
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• 2009

This study is on development of UV-cured hard coating compounds which have more improved abrasion resistance than existing UV-cured urethane-acrylic resin, to prevent a surface of a widely used PVC tile as a constructive material from being scratched. To make a high abrasion resistant hard coating solution compared to UV-cured urethane-acrylic resin which has no abrasion resistance and been used for PVC tiles, we added powder substances of different abrasion resistant level, $Al_2O_3$(Al-160SG-3), $Al(OH)_3$(SH-8W), $SiO_2$(KS-5000), etc., to the resin, changing their contents from 10% to 30% against quantities of resin, and compounded it using Ring-Mill. After coating PVC tiles with the hard coating solution using bar-coating method that can adjust a thickness, we estimated some surface properties-abrasion resistance, pencil hardness, adhesive power, thickness of coating, and so on. As a result, a hard coating solution added 30% $Al_2O_3$ powder to the resin had the finest surface properties-the first grade in abrasion resistance, H in pencil hardness, 100% in adhesive power, and a hard coating solution which showed excellent solidity and abrasion resistance has smaller particle size, higher powder content, and thicker coating thickness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3220-3230
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• 2014

This paper analyzes the house designs of Kazuyo Sejima and Ryue Nishizawa from the 1900s to the early 2000s' works. By analyzing the degree of space integration of each house using the Convex Map of the Space Syntax Theory, this study arrived at the following conclusions in the respects of private space and public space. First, from period 1 (the 1990s) to period 2 (the first half of the 2000s), the differences between average integration values of private space and public space in their works have decreased. Over time, in general, average integration values of private space have increased, and, on the other hand, those of public space have decreased, leading to smaller differences between two sets of values, which means that, as the integration degrees of private and public spaces have become similar, the boundary which divides spaces becomes blurry. Second, in terms of private space, average integration values of private space in S-3 (House in a Plum Grove) and S-4 (House in China), works of period 2, are the highest among those values of their all 10 works. We can identify that, closure degrees of private space in their works have fallen over time. Third, in terms of public space, average integration values of I-2 (Villa in the Forest), I-5 (S-House), and I-6 (Weekend House), works of period 1, are the highest among those values of their all 10 works. Public space has become more central and open from period 1 to period 2.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.724-731
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• 2016

As the structural damage caused by earthquakes has been gradually increasing, estimating the seismic fragility of structures has become essential for earthquake preparation. Seismic fragility curves are widely used as a probabilistic indicator of structural safety against earthquakes, and many researchers have made efforts to develop them in a more accurate and effective manner. However, most of the previous research studies used simplified 2D analytical models when deriving fragility curves, mainly to reduce the numerical simulation time; however, in many cases 2D models are inadequate to accurately evaluate the seismic behavior of a structure and its seismic vulnerability. Thus, this study provides a way to derive more accurate, but still effective, seismic fragility curves by using 3D analytical models. In this method, the reliability analysis software, FERUM, is integrated with the structural analysis software, ZEUS-NL, enabling the automatic exchange of data between these two software packages, and the first order reliability method (FORM), which is not a sampling-based method, is utilized to calculate the structural failure probabilities. These tools make it possible to conduct structural reliability analyses effectively even with 3D models. By using the proposed method, this study conducted a seismic vulnerability assessment of RC frame structures with their 3D analytical models.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.163-177
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• 2016

This study suggests a method for making a system of basic materials for the restoration of the 3X3 Kan central hall remains of a Buddhist temple from the Joseon Dynasty. Because there are both an extant hall and remains from the Joseon Dynasty, the basic material can be constructed through comparison with the floor plan. Multi-step comparisons were found to be the most suitable example for restoration. For this study, five parts of the 3x3 Kan remains were compared with 70 extant halls for a case study. For the first comparison, the limit of collection makes four examples in the whole examples. There are many relationships with the area and the length ratio of the front to the side as the comparison articles, so there are examples that satisfied both comparison articles. However, there is little relationship between the length ratio of the front Eokan to the front Hyeopkan and the length ratio of side Eokan to the side Hyeopkan. The construction method of the basic material shows the possibility of expansion with various directions that have pros and cons.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.302-307
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• 2016

The technology of multistage deep drawing has been widely applied in the metal forming industry, in order to reduce both the manufacturing cost and time. A battery can used for mobile phone production is a well-known example of multistage deep drawing. It is very difficult to manufacture a battery can, however, because of its large thickness to height aspect ratio. Furthermore, the production of the final parts may result in assembly failure due to springback after multistage deep drawing. In industry, empirical methods such as over bending, corner setting and ironing have been used to reduce springback. In this study, a bottoming approach using the finite element method is proposed as a practical and scientific method of reducing springback. Bottoming induces compression stress in the deformed blank at the final stroke of the punch and, thus, has the effect of reducing springback. Different cases of the bottoming process are studied using the finite element program, DYNAFORM, to determine the optimal die design. The results of the springback simulation after bottoming were found to be in good agreement with the experimental results. In conclusion, the proposed bottoming method is expected to be widely used as a practical method of reducing springback in industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.109-118
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• 2016

Language intervention through cooking activity programs is designed to provide an efficient teaching method and improved educational environment in the field of teaching. This program addresses the effects of this program on the language development of three three-year-old infants (M;2, F;1) in the Center in Seoul. A cooking topic suitable for the age of this group was selected. The language Intervention was conducted for 50 minutes per week for a total of 25 times, and made use of vocabulary, verbs and nouns related to cooking which were evenly distributed. In this study, the Peabody Picture Vocabulary Test-Revised (PPVT-R), receptive language age (RLA) and expressive language age (ELA), and Preschool Receptive-Expressive Language Scale (PRES) were used to analyze the collected data. After the study, the cooking activity was accomplished with normal development outcomes appearing in the ability of vocabulary, receptive language, expressive language, and integrated language. There is now a solid evidence base supporting the efficacy of cooking activity in producing positive outcomes in the language development of language delayed infants. Consequently, cooking can induce their active participation and interest and extend their language abilities through various experiences.