• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.1
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• pp.13-20
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• 2022

Aircraft weight is an important factor affecting performance and fuel efficiency. In the conceptual design stage of the aircraft, the process of balancing cost and weight is performed using empirical formulas such as fuel consumption cost per weight in estimating element weight. In addition, when an airline operates an aircraft, it promotes fuel efficiency improvement, fuel saving and carbon reduction through weight management activities. The relationship between changes in aircraft weight and changes in fuel consumption is called the cost of weight, and the cost of weight is used to evaluate the effect of adding or reducing weight to an aircraft on fuel consumption. In this study, the problems of the existing cost of weight calculation method are identified, and a new cost of weight calculation method is introduced to solve the problem. Using Breguet's Range Formula and actual flight data of the A350-900 aircraft, two weight costs are calculated based on take-off weight and landing weight. In conclusion, it was suggested that it is reasonable to use the cost of weight based on the take-off weight and the landing weight for other purposes. In particular, the cost of weight based on the landing weight can be used as an empirical formula for estimating element weight and optimizing cost and weight in the conceptual design stage of similar aircraft.

• Journal of Ginseng Research
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• v.37 no.2
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• pp.187-193
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• 2013

The effect of Korean red ginseng (KRG) on diabetic renal damage was investigated using streptozotocin (STZ)-induced diabetic rats. The diabetic rats showed loss of body weight gain, and increases in kidney weight and urine volume, whereas the oral administration of KRG at a dose of 100 or 250 mg/kg of body weight per day for 28 d prevented these diabetes-induced physiological abnormalities. Among the kidney function parameters, elevated plasma levels of urea nitrogen and creatinine in diabetic control rats tended to be lowered in KRG-treated rats. In addition, administration of KRG at a dose of 100 mg/kg body weight in the diabetic rats showed significant decreases in serum glucose and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), implying that KRG might prevent the pathogenesis of diabetic complications caused by impaired glucose metabolism and oxidative stress. KRG also significantly reduced advanced glycation end product (AGE) formation and secretion from kidney of diabetic rats. Furthermore, KRG decreased the levels of N-(carboxymethyl) lysine and expression of AGE receptor. KRG also reduced the overexpression of cyclooxygenase-2 and inducible nitric oxide synthase in the kidney via deactivation of nuclear factor-kappa B. We also found that KRG prevented STZ-induced destruction of glomerular structure and significantly suppressed high glucose-induced fibronectin production. Taken together, KRG ameliorates abnormalities associated with diabetic nephropathy through suppression of inflammatory pathways activated by TNF-${\alpha}$ and AGEs. These findings indicate that KRG has a beneficial effect on pathological conditions associated with diabetic nephropathy.

• Journal of Oriental Neuropsychiatry
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• v.17 no.2
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• pp.1-13
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• 2006

Objective : This study examined whether Yangsung program (oriental psychological weight regulation model based on Confucian ideas) is effective on weight loss, self esteem, three factor on eating questionnaires(restraint eating, disinhibition and hunger), distortion of body-image and biochemistry of blood. Method : 23 women were assigned randomly into 2 groups; experimental group(n=10) and control group(n=13). Experimental group had 7 personal sessions consisting of personal Yangsung therapy, meditation, general diet and exercise education. Control group had personal sessions with general diet and exercise education once a week for 6 weeks. All subjects were weighed and evaluated with Rosenberg self esteem scale, distortion of body-image, biochemistry of blood and three factor eating questionnaires at the beginning and end of the program. Result : There is significant difference between two groups in changes of self esteem, disinhibition and hunger(p<0.05). There is no significant difference in weight reduction and BMI between two groups. Conclusion : This study showed a new possibility of unique psychological program for obesity characterized by its philosophical context.

• Journal of Oriental Medical Thermology
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• v.9 no.1
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• pp.22-28
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• 2011

Purpose :To analyze body composition in postpartum women with cold-hypersensitivity, their edema index, skelectal muscle's weight and body fat were measured and analyzed with cold hypersensitive postpartum women compared with those of non-cold hypersensitivity. Methods : We studied 38 postpartum women visiting Gangnam Kyung-Hee Korean Hospital from 1 st October 2010 to 30th september 2011. they were subjected to Digital Infrared Thermal Imaging and those with thermal difference greater than $0.3^{\circ}C$ between anterior forearm and center of hand were diagnosed with cold hypersensitivity. Cold hypersensitivity group were consisted of 11 women, the other were consisted of 26 women. All of them were measured Edema index, skelectal muscle's weight and body fat by Inbody720(body composition scanner). We studied the difference of Body composition factor between two groups and relationship between cold-hypersensitivity, Edema index, skelectal muscle's weight and body fat by Independent Samples T-test and Spearman Correlation. Results : No significant differences were observed in edema index, skelectal muscle's weight and body fat between two groups. Conclusion : There was no significant relationship among the Cold-hypersensitivity and Body composition factor(Edema index, skelectal muscle's weight. body fat). But furthemore large scale study is required.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.3
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• pp.202-206
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• 2003

In this study, modified PbTi $O_3$ ceramics was manufactured to apply for 30MHz SMD type ceramic resonator with the variations of electrode weight. To investigate the effects of electrode weight on resonant characteristics of ceramic resonator using 3$^{rd}$ overtone thickness vibration mode, ceramic wafers for resonator were fabricated by evaporating electrode weights of 0.66, 1.765, 2.32, 3.87$\times$ 10$^{-4}$ g/c $m^2$ with silver, respectively. And then, SMD type ceramic resonators were fabricated with the size of 3.7$\times$3.1mm and electrode radius size of 0.77mm. With increasing electrode weight, resonant resistance was gradually decreased. At the electrode weight of 2.32$\times$10$_{-4}$ g/c $m^2$, mechanical quality factor( $Q_{mt3}$) and dynamic range(D.R) showed the maximum value of 2,152 and 49dB, respectively.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.7
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• pp.47-53
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• 2015

As the industrial development in Korea, the power demand is rapidly increased. The power system has been extended and complicated to meet the power demand. However, the fault current increases because the structure of power system reduces the equivalent impedance. One of the solutions to reduce the fault current is Superconducting Fault Current Limiter(SFCL) and the researches of SFCL application have much conducted. In this paper, we used the Circuit Breker Burden Index(CBBI) to select application location of SFCL because the CBBI may consider a fault current of each line. In addition, this paper divided the weight factor used to calculate the CBBI on a case by case basis and analyzed this characteristics through experiment.

• International Journal of Human Ecology
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• v.8 no.1
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• pp.27-37
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• 2007

The purpose of this study is to investigate the preference of the hand and the sensibility image of underwear textiles according to seasons. According to a recent survey of 109 college students, using a 7 scale evaluation to the preference of the hand and the sensibility image among 13 summer and 10 winter underwear textiles. The data was analyzed through mean, SD, factor analysis, t-test, Person correlation analysis and regression analysis using SPSS Win 11.0. The summer underwear textiles were classified according to six tactile factors: stiffness/surface unevenness, weight, elasticity, moistness, extension, and warm-cool and 3 sensibility image factors: elegant individual, modern, and sporty-casual. The winter textiles were classified according to six tactile factors: stiffness/surface unevenness, elasticity, warm-cool, drapability, moistness and flexibility and divided into 2 sensibility images: modern elegant and sporty-casual. Factors expressing hand and sensibility image according to season showed significant difference. In the summer, weight, in the winter, drapability and flexibility showed significant difference at the hand factor evaluation. The hand factors: weight, warm-cool and modern sensibility image factors effect the preference of summer underwear textile, also the hand factors-elasticity, stiffness/surface unevenness and the sensibility image factor-easy-sport-casual-effect the preference of winter textiles. Therefore, the thin, light, and cool textiles which are also gorgeous and sporty-casual are preferred for summer underwear textiles while soft, simple and comfortable textiles are preferred for winter textiles.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.224-233
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• 2023

This research was conducted at Langgur City, Southeast Maluku Regency, Maluku Province, Eastern Indonesia from November 2020 to February 2021 to study biological aspects of roundscads (Decapterus spp.) which consist of species composition, sex ratio, gonad maturation level, size distribution, length-weight relationship and condition factor. Samples were collected at traditional fish market in Langgur City. Fish samples collected at the market were put into cool box and then brought to the laboratory for further examination. Fish samples were identified, separated based on species, dissected to determine their sex and gonad maturation stage and then measured. Totally, there were 290 specimen collected which consist of five species namely Decapterus kurroides, D. macarellus, D. macrosoma, D. muroadsi and D. russelli. Sex ratio between male and female for all species showed 1:1. Gonad maturation level showed that stage I and II have higher percentage than stage III and IV indicates immature fish more dominant compare to mature one. Among five species found, D. macarellus has larger size while the smaller belongs to D. muroadsi. Results of length-weight relationship analysis showed that roundscads inhabiting Southeast Maluku waters have isometric and negative allometric growth pattern with relative condition factor around 1.00.

• Steel and Composite Structures
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• v.7 no.3
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• pp.201-217
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• 2007

Two combinatorial optimization algorithms, tabu search and simulated annealing, are presented for the minimum-weight design of geometrically non-linear steel plane frames. The design algorithms obtain minimum weight frames by selecting suitable sections from a standard set of steel sections such as American Institute of Steel Construction (AISC) wide-flange (W) shapes. Stress constraints of AISC Load and Resistance Factor Design (LRFD) specification, maximum and interstorey drift constraints and size constraints for columns were imposed on frames. The stress constraints of AISC Allowable Stress Design (ASD) were also mounted in the two algorithms. The comparisons between AISC-LRFD and AISC-ASD specifications were also made while tabu search and simulated annealing were used separately. The algorithms were applied to the optimum design of three frame structures. The designs obtained using tabu search were compared to those where simulated annealing was considered. The comparisons showed that the tabu search algorithm yielded better designs with AISC-LRFD code specification.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.71-76
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• 2003

The purpose of this study is the development, application and assessment of probability and artificial neural network methods for assessing landslide susceptibility in a chosen study area. As the basic analysis tool, a Geographic Information System (GIS) was used for spatial data management. A probability method was used for calculating the rating of the relative importance of each factor class to landslide occurrence, For calculating the weight of the relative importance of each factor to landslide occurrence, an artificial neural network method was developed. Using these methods, the landslide susceptibility index was calculated using the rating and weight, and a landslide susceptibility map was produced using the index. The results of the landslide susceptibility analysis, with and without weights, were confirmed from comparison with the landslide location data. The comparison result with weighting was better than the results without weighting. The calculated weight and rating can be used to landslide susceptibility mapping.