• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.207-214
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• 2002

The purpose of this study was to examine the putter head movement during the putting strokes. Highly skilled 5 golfers(less than 3 handicaps) and 5 novice golfers(having no golf experience) participated in this study. A target distance was 3 m. Movements of the putter head were recorded at 60 Hz with two video cameras(1/500 shutter speed). The results showed that the angle of the clubface of expert golfers was almost 1 degree, but the novice golfers were more than 6 degrees. Expert golfers moved their hands faster than the head movement, therefore the clubface was not opened during impact. However, the novice golfers moved their hands slower than the head movement, therefore the clubface was opened during impact. The ratio of input and output angles of total movement was 1:3-4, however, the ratio of input and output angles of impact zone was 1:2. The angle of normal vector of expert golfers was less than the angle of normal vector of novice golfers.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.1-16
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• 2002

The purposes of this study were to investigate the effects of strength training on the change of ground reaction force for the children with trisomy 21 Down syndrome. The subjects of this study were consisted of eight elementary school students with Down syndrome who participated in the strength training. The strength training was administered by six items such as squat, leg curl, leg extension, toe raise, sit-ups, and hyperextension. For strengthening muscle, each group also was treated by walking for 8 weeks, three times a week, 10-15RM, 3sets, which was based on the principle of progressive overload. For inquiring the effect of strength training, the ground reaction force variables were measured in two phases : before-training and 8 week-after training. The gait of each subject was acquisition using 2 AMTI force platforms set at 100 frequency. The results of this study were as follows: The pattern of vertical, antero-posterior and medio-lateral forces, trajectory of net COP and the timing ratio of reaching the each events were shown variously. So, it is not easy to explain these variables clearly. As the result of strength training, these variables were changed. However, the results of within subjects differ greatly, there was no difference statistically.

• Journal of Chest Surgery
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• v.32 no.5
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• pp.456-460
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• 1999

Background: Thoracic sympathectomy for hyperhidrosis has been recognized as an effective treatment using thoracoscopic devices and operative techniques, but the satisfaction has decreased due to a compensatory hyperhidrosis. Therefore, the postoperative results and compensatory hyperhidrosis were analyzed. We also measured the temperature differences in the hand and foot during the preoperative and postoperative periods and measured the blood flow of upper and lower extremities. Material and Method: From December 1995 to July 1998, total of 47 patients with hyperhidrosis underwent sympathectomy via VATS at the Department of Thoracic and Cardiovascular Surgery, Kangnam St. Mary's Hospital. The patients were evaluated for preoperative and postoperative temperature changes on the finger and toe, and preoperative and postoperative blood flows were measured by the Doppler examination on the digital artery, radial artery and dorsalis pedis artery. Result: There were no operative deaths but some complications existed: 7 pneumothorax, 3 recurrence and 1 Honor syndrome. Ninety-five percent of the patients also had compensatory sweating especially in the trunk. There were 5 patients who regretted recurring the operation because of the compensatory sweating. Sweating decreased in 46% of the sole hyperhidrosis patients. The temperature difference between preoperation and postoperation was 1$^{\circ}C$ on the right hand side and 1.9$^{\circ}C$ on the left hand side(P<0.05). There was no significant temperature difference on the sole. Blood flow increased significantly in the palm, but no difference in the sole. Conclusion: In conclusion, thoracic sympathectomy for hyperhidrosis is a safe and effective treatment but satisfaction has been decreased by the compensatory sweating; therefore, it is important to thoroughly explain the compensatory sweating prior to surgery. Improvement of the plantar hyperhidrosis is not due to a physiological change, but to a psychological stability.

• Journal of Korea Water Resources Association
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• v.45 no.11
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• pp.1157-1168
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• 2012

In this study, we assess changes in water quality trends over time based on certain control measurements in order to identify and analyze the cause of the trend in water quality. The current water pollution in the Nakdong River was analyzed, as it suggests that the significant changes in water quality have occurred in between 2006 and 2010. Based on monthly average data, we have examined for trends of the Nakdong River watershed in water temperature, Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP). Moreover, we have investigated seasonal variation of water quality of sites within the Nakdong River Basin by implementing further analyses such as, Correlation Coefficient, Regression Analysis, Hierarchical Clustering Method, and Time Series Analysis on SPSS. Geology and topography of the watershed, controlled by various conditions such as, climate, vegetation, topography, soil, and rain medium, have been affected by the non-homogeneity. Our study suggests that such variables could possibly cause eutrophication problems in the river. One possible way to overcome this particular problem is to lay up a ship on the river by increasing the nasal flow measurement of the Nakdong River during rainy season. Moreover, the water management requires arranging the measurement of the flow in order to secure the river while the numerous construction projects need to be continuously observed. However, the water is not flowing tributary of the reason for the timing to be flowing in a natural state of river water and industrial water intake because agriculture. Therefore, ongoing research is needed in addition to configuration of all observations.

• Journal of Biomedical Engineering Research
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• v.30 no.5
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• pp.401-411
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• 2009

In this paper, we correct pulse wave velocity(PWV) with heart-rate and derive regression equations to estimate intima-media thickness(IMT). Widely used methods for diagnosis of arteriosclerosis are IMT and PWV. Arterial wall stiffness determines the degree of energy absorbed by the elastic aorta and its recoil in diastole but there is not correlation between sclerosis and IMT in an existing study. In this study, we will correct PWV with heart-rate and get regression equation to estimate IMT using heart-rate correction index(HCI). We executed experiments for this study. Made up question of physical condition and measured electrocardiogram(ECG), photoplethysmogram (PPG) of finger-tip and toe-tip and ultrasound image of carotid artery. Calculated PWV and IMT using ECG, PPG and ultrasound image. We found that every p-value between PWV and IMT is not significant(<0.05). But p-value between IMT and HCI which is a corrected PWV using heart-rate is significant(>0.01). We use HCI and various measured parameter for estimating regression equation and apply backward estimation to select parameters for regression analysis. Result of backward estimation, found that only HCI is possible to derive proper regression equation of IMT. Relationship between PWV and IMT is the second order. Result of regression equation of E-H PWV is $R^2$=0.735, adj $R^2$=0.711. This is the best correlation value. We calculate error of its analysis for verification of earlobe PWV regression equation. Its result is RMSEP=0.0328, MAPE(%) = 4.7622. Like this regression analysis, we know that HCI is useful parameter and relationship between PWV, HCI and IMT. In addition, we are able to suggest possibility which is that we can get different parameter of prediction throughout just one measurement.

• Journal of Acupuncture Research
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• v.23 no.3
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• pp.57-65
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• 2006

Objectives : It is known that the five Su points are very useful clinically. The following study was undertaken in order to find out the general characteristic and the origin of the five Su points. Methods: We investigated the relation of symptoms that are treated by five Su points and Shi-Dong Suo-Sheng-Bing(是動 所生病). The main reference book was Zhen Jiu Jia Yi jing(鍼灸甲乙經) and the author took Liver Meridian of Foot Gworeum(足厥陰肝經) as an example. Results : 1. Five Su point of Liver Meridian of Foot Gworeum(足厥陰肝經) treats Shi-Dong-Bing(是動病) of Liver Meridian of Foot Gworeum. It is peculiarity of Five Su point of Liver Meridian of Foot Gworeum, differed from the others acupoints. Symptoms of Shi-Dang-Bing appears with the abnormal pulsation of Merdian Gi(脈氣), and the special feature of Shi-Dang-Bing is the symptoms are consisted of disorders of whole body, trobles of an internal organ, and psychosomatic disorders. 2. In , it is described the part of pulse feeling for Shi-Dong-Bing(是動病) of Liver Meridian of Foot Gworeum(足厥陰肝經) as ‘A region that is 2 Chon(寸) from the basic digital joint of the first toe’. This region is agree with the acupoint of Liver Meridian of Foot Gworeum in , . And Haeng-gan(行間) Tae-chung(太衝), members of five Su-points of Liver Meridian of Foot Gworeum is situated the same region. So we suppose that the part of pulse feeling for Shi-Dong-Bing of Liver Meridian of Foot Gworeum is transformed into Haeng-gan(行間) Tae-chung(太衝), among the five Su points.

• Journal of Korean Orthopaedic Sports Medicine
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• v.8 no.1
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• pp.39-45
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• 2009

Purpose: We intended to classify the pattern and to seek the cause of fractures and/or dislocations related to middle and high school Taekwondo athletes in competition and try to get the ways for preventing them. Materials and Methods: We studied 50 fractures and dislocations of the athletes in competition, which were surveyed in 2005-2007 national middle and high school Taekwondo tournament annually. We analyzed the type and the cause of the injury, performed survey at postinjury l year in 32 cases, sought proper treatments and methods for prevention. Results: The 26 cases (52%) of foot fracture, 15 cases (30%) of hand fracture and 9 cases (18%) of forearm fracture are occurred in this study. The 9 cases (28%) of satisfaction in treatment, 15 cases (47%) of average and 8 cases (25%) of dissatisfaction are surveyed in the 32 cases. The causes of dissatisfaction are lack of rest (7 cases), excessive training (5 cases), immoderate participation of match (6 cases) and the others. The athletes were returned to the match before complete recovery in 21 cases (67%). Conclusion: The causes of fractures and dislocations in middle and high school Taekwondo athletes were stroke on upper and lower extremities and high-speed hyperflexion injury that was occurred during spraining of great toe on the floor. We consider that the athletes need the development of effective protector, improvement of equipment in stadium and enough rest and education.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3833-3838
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• 2009

This paper introduces a measurement system for mechanical properties of sport shoes using an industrial robot. The robot system used in this paper is a commercial Puma type robot system(FARA AT2 made by SAMSUNG Electronics) with 6 joints and the end-effector is modified to produce a human walking motion. After analyzing human walking with a high speed video camera, each joint angle of the robot system is extracted to be used in the robot system. By using this system, ground impact forces were measured during stepping motion with 3 different shoe specimens made of 3 different hardness outsoles, respectively. As other mechanical properties, both bending moments to bend the toe part of the same specimen shoes and pronation quantities during walking motion were measured as well. In the impact test with the same depth of deformation under the ground level, the effect of the outsole hardness was clearly appeared such that the harder outsole produces the higher ground reaction force. The bending test and the pronation test also show proportional increments in the bending stiffness and the moment Mx according to the outsole hardness. Throughout such experiments, the robot system has produced consistent results so that the system could be used in obtaining valuable informations for a shoe designing process.

• Journal of Energy Engineering
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• v.22 no.2
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• pp.184-196
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• 2013

We need to develop new renewable energy that could fundamentally replace fossil fuel, since the volume of economy and industry of our time becomes uncontrollably enormous. One of the alternative is to develop energy based on marine biomass, which would meet environment and energy needs at the same time. The marine bio-energy productions is supposed to occupy 50% to 500 million TOE in bio-energy production that is based on the Korean 3rd new renewable energy technology development, utilization, supply plan until 2030. This study attempts to apply input-output analysis to investigating the economic impacts of marine bio-energy development project in the Korean national economy. More specifically, this study shows what national economy effect of production-inducing effect, value-added inducing effect, employment-inducing effect, and R&D-inducing effect are explored with demand-driven model. Furthermore, this study attempts to define and classify the marine bio-energy development project sector from I-O table. Also, this study pays particular attention to marine bio-energy development project by taking the industry as exogenous specification and then investigating its economic impacts. The Marine bio-energy development project case 223 billion won, production-inducing effect, value-added inducing effect, and employment-inducing effect are 312 billion won, 87 billion won, 1,151 persons, and 5 billion won respectively. These quantitative information can be usefully utilized in the policy-making for the industrialization of marine bio-energy development project.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.57-64
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• 2007

This study was conducted to characterize on the relationships among rainfall intensity, slope angle and pore water pressure in the gneissic weathered soil by landslide laboratory flume tests. Under the several test conditions dependent on rainfall intensity and slope angle, the authors measured pore water pressure, failure and displacement of slope on a regular time interval. According to the test results, the increasing times of pore water pressures have direct proportional trends to the rainfall intensity. The pore water pressure was increased earlier at the head part of slope than the toe part. Compared with the test results of Chae et al(2006), the results of this study explain that the seepage velocity in the gneissic weathered soil is slower than that in the standard sands. It results in faster and ear-lier increase of pore water pressure at the head part of slope due to slow flow of water in the gneissic weathered soil. In case of the relationship between slope angle and pore water pressure, gentle slope angle has faster increase of pore water pressure than steeper slope angle. It is also thought to be due to slow seepage velocity and flow velocity in the gneissic weathered soil.