• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.379-389
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• 2019

The study empirically investigates financial factors that may influence on corporate R&D intensity during the post-era of the global financial turmoil (from 2010 to 2015) to mitigate possible spillover effect associated with the crisis. Concerning the empirical research settings of the study, chaebol firms listed in the KOSPI stock market are used as sample data with adopting various econometric estimation methods to enhance validity of the results. In the first hypothesis test, it is found that there exist inter-industry financial differences in terms of the ratio of R&D expenditure across all the sample years, but the statistical differences may arise from only a few domestic industries beloning to the high-growth sector. Moreover, it is also interesting to identify that, for the high-tech sector, 3 explanatory variables such as R&D intensity in a prior year, firm size and change in cash holdings are proved to be financial factors to discriminate between chaebol firms and their counterparts of non-chaebol firms, whereas a proportion of tangible assets over total assets as well as the former two variables are shown to be significant factors on the R&D intensity for the low-tech sector.

• Journal of the Korean Wood Science and Technology
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• v.7 no.2
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• pp.3-30
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• 1979

Larch ($\underline{Larix}$ $\underline{leptolepis}$ GORDON), one of the major afforestation species in Korea in view of its growing stock and rate of growth, is not favored as a raw material for pulp due to its low yield of pulp and difficulties with bleaching arising from the high content of extractives in wood, and the high heartwood ratio and the active phenolics, respectively. The purpose of this study is to investigate the characteristics of firstly pulping with various additives of cellulose protector for the yield of pulp, and secondly bleaching with oxygen for chlotination-alkali extraction of five stage-sequence to reduce chlorine compounds in bleaching effluents. The kraft cooking liquor for five age groups of larchwood was 18 percent active alkali with 25 percent sulfidity and 5 : 1 liquor-to-wood ratio, and each soda liquor for sap-and heart-wood of the 15-year-old larchwood was 18 percent alkali having one of the following cellulose protectors as the additive; magnesium sulfate ($MgSO_4$, 2.5%), zinc sulfate ($ZnSO_4$, 2.5%), aluminium sulfate ($Al_2(SO_4)_3$, 2.5%), potasium iodide (KI, 2.5%), hydroquinone (HQ, 2.5%), anthraquinone (AQ, 0.1%) and ethylene diamine (EDA, 2.5%). Then each anthraquinone-soda liquor for the determination of suitable cooking condition was the active alkali level of 15, 17 and 19 percent with 1.0, 0.5 and 0.1 percent anthraquinone, respectively. The cooking procedure for the pulps was scheduled to heat to 170$^{\circ}C$ in 90 minutes and to cook 90 minutes at the maximum temperature. The anthraquinone-soda pulps from both heartwood and sapwood of 15-year-old larchwood prepared with 0.5 percent anthraquinone and 18 percent active alkali were bleached in a four-stage sequency of OCED. (O: oxygen bleaching, D: chlorine dioxide bleaching and E: alkali extraction). In the first stage oxygen in atmospheric pressure was applied to a 30 percent consistency of pulp with 0.1 percent magnesium oxide (MgO) and 3, 6, and 9 percent sodium hydroxide on oven dry base, and the bleached results were compared pulps bleached under the conventional CEDED (C: chlorination). The results in the study were summarized as follows: 1. The screened yield of larch kraft pulp did not differ from particular ages to age group, but heartwood ratio, basic density, fiber length and water-extractives contents of wood and the tear factor of the pulp increased with increasing the tree age. The total yield of the pulp decreased. 2. The yield of soda pulp with various chemicals for cellulose protection of the 15-year-old larchwood increased slightly more than that of pure soda pulp and was slightly lower than that of kraft pulp. The influence of cellulose protectors was similar to the yield of pulps from both sapwood and heartwood. The effective protectors among seven additives were KI, $MgSO_4$ and AQ, for which the yields of screened pulp was as high as that of kraft pulp. Considering the additive level of protector, the AQ was the most effective in improving the yield and the quality of pulp. 3. When the amount of AQ increased in soda cooking, the yield and the quality of the pulp increased but rejects in total yield increased with decreasing the amount of active alkali from 19 to 15 percent. The best proportion of the AQ seemed to be 0.5 percent at 17 percent active alkali in anthraquinone-soda pulping. 4. On the bleaching of the AQ-soda pulp at 30 percent consistency with oxygen of atomospheric pressure in the first stage of the ODED sequence, the more caustic soda added, the brighter bleached pulp was obtained, but more lignin-selective bleaching reagent in proportion to the oxygen was necessary to maintain the increased yield with the addition of anthraquinone. 5. In conclusion, the suitable pulping condition for larchwood to improve the yield and quality of the chemical pulp to the level for kraft pulp from conventional process seemed to be. A) the selection of young larchwood to prevent decreasing in yield and quality due to the accumulation extractives in old wood, B) the application of 0.5 percent anthraquinone to the conventional soda cooking of 18 percent active alkali, and followed, C) the bleaching of oxygen in atmospheric pressure on high consistency (30%) with 0.1 percent magnesium oxide in the first stage of the ODED sequence to reduce the content of chlorine compounds in effluent.

• Journal of Intelligence and Information Systems
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• v.27 no.1
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• pp.65-82
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• 2021

Stock market investors are generally split into foreign investors, institutional investors, and individual investors. Compared to individual investor groups, professional investor groups such as foreign investors have an advantage in information and financial power and, as a result, foreign investors are known to show good investment performance among market participants. The purpose of this study is to propose an investment strategy that combines investor-specific transaction information and machine learning, and to analyze the portfolio investment performance of the proposed model using actual stock price and investor-specific transaction data. The Korea Exchange offers daily information on the volume of purchase and sale of each investor to securities firms. We developed a data collection program in C# programming language using an API provided by Daishin Securities Cybosplus, and collected 151 out of 200 KOSPI stocks with daily opening price, closing price and investor-specific net purchase data from January 2, 2007 to July 31, 2017. The self-organizing map model is an artificial neural network that performs clustering by unsupervised learning and has been introduced by Teuvo Kohonen since 1984. We implement competition among intra-surface artificial neurons, and all connections are non-recursive artificial neural networks that go from bottom to top. It can also be expanded to multiple layers, although many fault layers are commonly used. Linear functions are used by active functions of artificial nerve cells, and learning rules use Instar rules as well as general competitive learning. The core of the backpropagation model is the model that performs classification by supervised learning as an artificial neural network. We grouped and transformed investor-specific transaction volume data to learn backpropagation models through the self-organizing map model of artificial neural networks. As a result of the estimation of verification data through training, the portfolios were rebalanced monthly. For performance analysis, a passive portfolio was designated and the KOSPI 200 and KOSPI index returns for proxies on market returns were also obtained. Performance analysis was conducted using the equally-weighted portfolio return, compound interest rate, annual return, Maximum Draw Down, standard deviation, and Sharpe Ratio. Buy and hold returns of the top 10 market capitalization stocks are designated as a benchmark. Buy and hold strategy is the best strategy under the efficient market hypothesis. The prediction rate of learning data using backpropagation model was significantly high at 96.61%, while the prediction rate of verification data was also relatively high in the results of the 57.1% verification data. The performance evaluation of self-organizing map grouping can be determined as a result of a backpropagation model. This is because if the grouping results of the self-organizing map model had been poor, the learning results of the backpropagation model would have been poor. In this way, the performance assessment of machine learning is judged to be better learned than previous studies. Our portfolio doubled the return on the benchmark and performed better than the market returns on the KOSPI and KOSPI 200 indexes. In contrast to the benchmark, the MDD and standard deviation for portfolio risk indicators also showed better results. The Sharpe Ratio performed higher than benchmarks and stock market indexes. Through this, we presented the direction of portfolio composition program using machine learning and investor-specific transaction information and showed that it can be used to develop programs for real stock investment. The return is the result of monthly portfolio composition and asset rebalancing to the same proportion. Better outcomes are predicted when forming a monthly portfolio if the system is enforced by rebalancing the suggested stocks continuously without selling and re-buying it. Therefore, real transactions appear to be relevant.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1172-1182
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• 1998

Background: Primary goal of anticoagulation treatment in patients with mechanical heart valve is the effective prevention of thromboembolism and safe avoidance of bleeding as well. Material and Method: Two-hundred and nine patients with the St. Jude Medical prosthesis operated on between 1984 and 1995, for mitral(MVR 122), aortic(AVR 39) and double mitral and aortic valve replacement(DVR 48) respectively, were studied on the practically achieved levels of anticoagulation and the clinical outcomes. Patients were on Coumadin and followed up by monthly visit to outpatient clinic for examination and prothrombin time measurement to adjust the International Normalized Ratios(INRs) within the low-intensity target range between 1.5 and 2.5. Result: A total anticoagulation follow-up period was 1082.0 patient- years(mean 62.1 months) and INRs of 10,205 measurements were available for evaluation. The accomplished INRs among the replacement groups were not significantly different and only 65% of INRs were within the target range. And, in individual patients, only 37% of patients had INRs included within the target range in more than 70% of tests during follow-up period. The levels of INRs in patients with atrial fibrillation, which was found in 57% of patients, were definitely higher than the ones measured in patients with regular rhythm(p<0.001). Thromboembolisms were experienced by 15 patients with the incidence of 1.265%/patient- year(MVR 1.412%, AVR 0.462% and DVR 1.531%/patient-year) and major bleeding by 4 patients with the incidence of 0.337%/patient-year(MVR 0.424%, AVR none and DVR 0.383%/patient-year). Frequent as well as prolonged missing of prothrombin time tests was the main risk factor strongly associated with the thromboembolic complications(odds ratio 1.99). The proportion of INRs within target range of less than 60% in individual patient was the highly significant risk factor of both thromboembolic and overall embolic and bleeding complications(p<0.004 and p<0.002 respectively). Conclusion: In conclusion, the low-intensity therapeutic target range of INRs was adequate in patients with AVR and in sinus rhythm. However, the patients with replacement of the mitral valve were more likely to require higher target range of INRs, especially in the presence of atrial fibrillation, to achieve the practical levels of anticoagulation enough to prevent thromboembolic complications effectively. For the higher therapeutic target range of INRs between 2.0∼3.0, further accumulation of clinical evidences are required. It is highly desirable to improve the patients' compliance under continuous instructions in visiting outpatient clinic and in taking daily Coumadin without omission and to keep INRs consistently within optimal range with tight control for minimization of chances and of periods of exposure to the risk of complications. And, particularly, patients with high risk of complications and with wide fluctuation of INRs should be better managed with frequent monitoring anticoagulation levels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1008-1017
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• 2005

The purpose of this study was to evaluate the Quantity and Quality of food and nutrient intake of preschool children. The subjects were 57 children aged 3 to 6 years in Gumi day-care centers. Total daily dietary intakes were calculated by weighing food consumed at the day-care centers taken together with dietary records by children's mothers for intakes at home. This survey was conducted during 3 days including week and weekend days. Diet Quality was assessed by NAR (Nutrient Adequacy Ratio), MAR (Mean Adequacy Ratio), food group pattern and DDS (Dietary Diversity Score). The daily food intake was 992.7g, the plant food intake $(68\%)$ was higher than animal food intake $(32\%)$. The daily energy intake was 1249.2 kcal $(85\%\;RDA)$ and protein 43.8g $(153.6\%\;RDA)$. Percentage of calcium, iron, and niacin consumed below $75\%$ of RDAs were $29.8\%,\;35.1\%\;and\;28.1\%$, respectively. Proportions of energy from carbohydrate, protein and fat were $61.0\%,\;14.1\%\;and\;25.5\%$, respectively. Calorie intake proportion of breakfast, lunch, dinner and snack were $15\%,\;20\%,\;19\%\;and\;46\%$, respectively. The NAR of Ca and Fe and MAR were 0.84, 0.85 and 0.92, respectively. Thirty-one point six percent of children consumed 5 food groups (GMFVDS=110111) per day. Persons who had higher DDSs correlated positively with NAR and MAR. As a result, dietary intake of preschool children partially showed a problem of over and under nutrition in Quantity or Quality. We hope that the result of this study could be helpful for developing the nutrition education program for the health and nutrition of preschool children.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.259-266
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• 2011

This study was performed to develop an odor-reduced Korean traditional Cheonggukjang (fermented soybean paste) by adding Job's tears to Cheonggukjang made with soybean (control) only. The study included the determination of best addition percentage of Job's tears versus soybean, sensory evaluation, and aroma patterns and its components as well as proximate composition analyses of Cheonggukjang. Job's tears Cheonggukjang (CAJT) was prepared by inoculating Bacillus subtilis and fermented at $40^{\circ}C$ for 48 hours. Ratios of soybean : Job's tears for Job's tears Cheonggukjang were 1:1, 2:1, 3:1, and 4:1, respectively. In comparison of proximal composition, Job's tears Cheonggukjang was high in moisture and carbohydrates, but low in calorie, fat, protein, ash and amino nitrogen. The pH of CAJT was lower than those of control and conventional Cheonggukjang (CC) sold in the market, and the acidity was the lowest in CC. The color of Job's tears Cheonggukjang appeared the whiter and more yellowish, but less reddish in proportion to contents of Job's tears. The contents of viscous substances were higher in CAJT compared with those of control and CC. The contents of glutamic acid, the major components of viscous substances were lower in CAJT than in control and CC, and the contents of fructose higher in CAJT. The scores of sensory evaluation were the highest in Job's tears Cheonggukjang mixed with soybean : Job's tears=4:1. The aroma pattern of CC analyzed was conspicuously dissimilar to the control and CAJT and also discriminated by electronic nose examination. The pyrazines, volatile compounds peculiar to Cheonggukjang, were found to be lower in CAJT by SPME-GC/MS assay. Additionally, the acetic acid, butanoic acid, and naphthalene causing off-flavor were identified in CC, but not in Job's tears Cheonggukjang. The strength of odor through sensory evaluation was by far the lowest in CAJT among the groups. From the findings, it had shown that Job's tears Cheonggukjang would be produced successfully when the ratio of 4:1 (soybean : Job's tears) is employed. Also, it was proved that appropriate ratio of Job's tears addition makes Cheonggukjang odor-reduced and well accepted by people.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.31-40
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• 2017

This study was undertaken to evaluate the quality characteristics and antioxidant characteristics of commercially available mixed grains in Korea. The quality characteristics of mixed grain products studied were the mixing ratio, water binding capacity, water solubility, swelling power, and pasting characteristics. The antioxidant characteristics assessed the total polyphenol, flavonoid contents, DPPH and ABTS radical scavenging activities. The mixing ratio of commercially available mixed grain products consisted of 5~25 kinds of grains, with maximum products containing 15-grain products. The water binding capacity, water solubility, and swelling power in commercially available mixed grain products were 99.83~122.83%, 6.91~39.26% and 7.76~86.92%, respectively. The peak, trough, breakdown, final and setback viscosity were $31.53{\pm}20.17RVU$, $25.24{\pm}13.22RVU$, $6.29{\pm}7.43RVU$, $50.27{\pm}25.84RVU$ and $18.74{\pm}8.68RVU$, respectively. Total polyphenol and flavonoid contents were $817.14{\sim}2,524.29{\mu}g\;GAE/g$ and $106.36{\sim}1,099.09{\mu}g\;CE/g$, respectively. The DPPH and ABTS radical scavenging activities were 31.91~151.70 mg TE/100 g and 28.09~119.92 mg TE/100 g, respectively. Products with high phenol content and radical scavenging activity were found to contain greater proportion of brown rice, colored rice, barley and soybean.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.183-192
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• 2004

This pot experiment was conducted to investigate the effects of systematic variation application of Fe, Mn, Cu, and Zn on forage performance of orchardgrass and white clover. The treatments of systematic variation were 0/100, 25/75, 50/50. 75/25, and $100/0\%$ in the Fe/Cu(trial-1). Mn/Zn(trial-2), and Fe+Cu/Mn+Zn(trial-3), respectively The treatments of Fe/Mn/Cu/Zn(trial-4) were composed of $70\%$ for main element and $10\%$ for other 3 elements, respectively. 1. The contents of N-compounds in forages tended to be in inverse proportion to the yields. In the Mn/Zn trial, the 0/l00 to white clover resulted in the relatively high contents of soluble N-compounds and low ratio of pure protein/soluble N-compounds in company with a severe yield decrease. 2. In the Fe+Cu/Mn+Zn trial, the 0/100 and 100/0 resulted in the somewhat high contents of N-compounds in white clover. It was likely to be caused by the concentration effect derived from yield decrease. In addition, the 100/0 resulted in the relatively high content of soluble N-compounds and low ratio of pure protein/soluble N-compounds. The protein synthesis in white clover was likely to be negatively influenced by the 100/0. 3. In the Fe/Mn/Cu/Zn trial, white clover showed the low contents of crude and pure protein at the 1st cut. It was likely to be caused by the unbalanced mutual ratios derived from the high application levels of each single element. 4. In white clover at the 5th cut, the 0/100 of Mn/Zn and 100/0 of Fe+Cu/Mn+Zn resulted in the relatively high content of K. It was likely to be caused by the concentration effect derived from yield decrease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.197-206
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• 2003

Physiological functions of raw grain diet composed of brown rice and Job's Tear (1 : 1) were evaluated in rats raised with nutritionally unbalanced diet including 1% cholesterol, high proportion of animal lipids (lard: soybean oil : 8 : 2), sub-optimal levels of vitamin and mineral mixture along with 0.5% ethanol in drinking water for 4 weeks. Control rats were fed the AIN-93G diet for 9 weeks, and nutritionally unbalanced rats were divided into 3 groups, and fed one of the following diets with 0.5% ethanol in drinking water for another 5 weeks: unbalanced control diet (UCD), raw grain diet (RGD) (UCD +20% brown rice and Job's Tear mixture, and cooked grain diet (CGD)(autoclaved RGD at 121$^{\circ}C$ for 3 hours). Feeding UCD for 5 weeks significantly lowered the food efficiency ratio (FER) of rats than the value for control animals, and dietary supplementation of brown rice and Job's Tear mixture to UCD significantly restored the FER. Serum total cholesterol concentration was significantly lowered in rats fed RGD (24% decrease) or CGD (16% decrease) compared to the value for rats fed UCD. Feeding RGD for 5 weeks significaly lowered the serum LDL+VLDL-cholesterol concentration (26% decrease), as well as the hepatic cholesterol level (16% decrease) than the values for UCD rats. Animals fed CGD (38% decrease) or RGU (59% decrease) showed significantly lower level of hepatic thiobarbituric acid reactive substances (TBARS) compared to the value for rats fed UCD (p<0.05), although hepatic activities of antioxidative enzymes were not influenced by dietary supplementation. Feeding RGD for 5 weeks significantly increased CD4$^{＋}$ T-cell population along with CD4$^{＋}$/CD8$^{＋}$ ratio of mesenteric lymph nodes compared to those for UCD rats (p<0.05). In conclusion, dietary supplementation of brown rice and Job's Tear mixture as raw grains exhibited superior activity lowering blood and hepatic levels of cholesterol, and improving mesenteric lymph nodes immune function of rats to the cooked grain mixture of identical ingredients.

• Journal of Acupuncture Research
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• v.30 no.4
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• pp.55-68
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• 2013

Objectives : The purpose of this study is to analyze the distribution, relationship, prognosis and improvement score of idiopathic facial palsy inpatients according to constitutional differentiation ; Sasang constition, Hyungsang classification, Sasang constition combined with Hyungsang classification. Methods : A study was done on 102 patients who were diagnosed and treated as idiopathic facial palsy from April 2012 to Nomember 2012 at the Department of Acupuncture and Moxibution Medicine, Dong-eui Oriental University Hospital. Medical records of inpatinets who underwent facial ENoG, NET test were analyzed. Changes of HBGS grade and Yanagihara's score were also evaluated. We classified inpaients acording to Sasang constitution by consulting to Department of Sasang constitutinal medicine, and to Hyungsang classification(Dam-body, Bangkwang-body) by measuring under medical system of 3D facial shapes(RS-400FL). The constitutional differentiation and general characteristics were initially analyzed, and valuse on ENoG, NET were correlated with constitutinal differentiation. Results of HBGS and Yanagihara's score were also correlated with constitutinal differentiation. Results : 1. Each 39.2 percent of idiopathic facial palsy inpatients were the Taeeumin and Soyangin, 21.6 percent were the Soeumin. 2. 75.5 percent of idiopathic facial palsy inpatients were the Bangkwang-body, 24.5 percent were the Dam-body. 3. 34.3 percent of idiopathic facial palsy inpatinets were the Taeeum-Bangkwang, 21.6 percent were the Soyang-Bangkwang, 19.6 percent were the Soeum-Bangkwang, 17.6 percent were the Soyang-Dam, 4.9 percent were the Taeem-Dam, 2 percent were the Soeum-Dam. 4. By sex, the each ratio of Taeeumin, Soeumin, Bangkwang-body, Taeeum-Bangkwang, Soeum-Bangkwang, Soyang-Bangkwang was higher in female, that of Dam-body, Taeeum-Dam, Soyang-Dam was higher in male. 5. By relations between Sasang constitution and Hyungsang classification, the each ratio of Taeeumin and Soeumin was higher in Bangkwang-body. 6. By values on ENoG and NET, evaluations of HBGS's grade and Yanagihara's score, there were no significant difference. Conclusions : In idiopathic facial palsy inpatients, the proportion of Taeeum and Soyang among the Sasang constitution was higher, that of Dam among the Hyungsang classification was higher, that of Taeeum-Bangkwang among the Sasang combined with Hyungsang was the highest. It would seem that Bangkwang-body, female were closely related to Taeeumin, Soeumin. Also, Dam-body were closely related to male. But when comparing groups, there was no statistically significant difference in prognosis and improvement.