• Wind and Structures
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• v.19 no.4
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• pp.443-465
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• 2014

Hyperbolic thin-shell cooling towers have complicated vibration modes, and are very sensitive to the effects of group towers and wind-induced vibrations. Traditional aero-elastic models of cooling towers are usually designed based on the method of stiffness simulation by continuous medium thin shell materials. However, the method has some shortages in actual engineering applications, so the so-called "equivalent beam-net design method" of aero-elastic models of cooling towers is proposed in the paper and an aero-elastic model with a proportion of 1: 200 based on the method above with integrated pressure measurements and vibration measurements has been designed and carried out in TJ-3 wind tunnel of Tongji university. According to the wind tunnel test, this paper discusses the impacts of self-excited force effect on the surface wind pressure of a large-scale cooling tower and the results show that the impact of self-excited force on the distribution characteristics of average surface wind pressure is very small, but the impact on the form of distribution and numerical value of fluctuating wind pressure is relatively large. Combing with the Complete Quadratic Combination method (hereafter referred to as CQC method), the paper further studies the numerical sizes and distribution characteristics of background components, resonant components, cross-term components and total fluctuating wind-induced vibration responses of some typical nodes which indicate that the resonance response is dominant in the fluctuating wind-induced vibration response and cross-term components are not negligible for wind-induced vibration responses of super-large cooling towers.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.99-102
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• 2007

Pressure Sensitive Paint(PSP) means a reacting paint in pressure. The calibration of PSP and the wind tunnel test of PSP painted model are required to measure pressure using by PSP. Therefore, the post processing from these results shows the information and image of the pressure distribution. PSP can show the information of total pressure from the wind tunnel test and the calibration. In this study, equipments of PSP are composed, and calibration is accomplished using by PSP. Results of design and manufacturing calibration chamber till ability of advance calibration system study.

• Journal of Korean Foot and Ankle Society
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• v.10 no.2
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• pp.125-132
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• 2006

Purpose: The purpose of this study was to evaluate pressure distribution on the foot with the use of custom made foot orthosis and evaluate influential factors in young people using custom orthosis. Materials and Methods: 22 individuals comprised of young males and females were evaluated by radiograph, pedobarograph, and satisfaction rate and VAS score. The data was analyzed statistically to find influential factors for satisfaction after wearing the foot orthosis. Results: Around 50% of participants were satisfied in wearing the custom made foot orthosis. Initial VAS score of satisfaction of $36.2{\pm}19.7$ improved to $73.1{\pm}15.6$ after application of foot orthosis. There was a statistically significant difference. Talo-second metatarsal angle on AP radiograph after orthosis application was significantly related to satisfaction. On analysis of pedobarograph data, total contact area was increased and weight distribution was transferred medially on ambulation with the orthosis applied. Conclusion: Before designing the foot orthosis, individual foot factors such as foot anatomy and foot pressure distribution should be evaluated for foot comfort and better patient satisfaction.

• Journal of the Korean Society of Physical Medicine
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• v.17 no.2
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• pp.53-62
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• 2022

PURPOSE: This study was conducted to investigate the effect of a real-time pressure feedback provided during gait training on the weight weight distribution of the inner part of mid-foot in paralyzed side and gait function in stroke patients. METHODS: A total of 24 patients with hemiplegic stroke in a rehabilitation hospital were randomly assigned to the experimental and control group. All participants (n = 24) performed 15 min of comprehensive rehabilitation therapy 5 times a week for a period of 4 weeks. Additionally, the experimental group and control group underwent gait training with a real time feedback and general gait training, respectively, for 15 min five times a week for 4 weeks. Weight distribution and gait function were measured before and after the 4-week training. RESULTS: Significant increases in the weight distribution (WD), stance time (ST) and step length (SL) of the paralyzed side, and a significant decrease in the 10 m walking test (10 MWT) observed after training in the two groups (p < .05). The experimental group showed larger changes in the all variables than the control group (WD, +10.5 kg vs. +8.8 kg, p < .05; ST, 12.8 s vs. 4.9 s, p < .05; SL, 4.9 cm vs. 1.7 cm, p < .05; 10 MWT, -3.5 s vs. -1.0 s, p < .05, respectively). CONCLUSION: Gait training with a real-time feedback might be effective in improving the normalization of weight bearing of the paralyzed lower extremity and gait function of stroke patients, and be considered to be a more effective gait training for improving the abilities than the general gait training.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.9-15
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• 1968

Changes in gastrointestinal tissue blood volume induced by variations of venous pressure between 6 and 40 mmHg were studied in 32 rabbits. Venous pressure lowering was produced by withdrawal of appropriate volume of blood and venous pressure elevation was obtained by partial occlusion of intra-thoracic vena cava inferior. Estimation of regional tissue blood volume was performed by means of regional distribution of injected $Cr^{51}-labeled$ red blood cells. The following results were obtained. 1. At the normal control venous pressure value of 18 mmHg, spleen showed the highest value of tissue blood volume expressed on weight basis, namely, $111{\mu}l/gm$, Liver tissue blood volume was $95\;{\mu}l/gm$, small intestine 24 and stomach $21\;{\mu}l/gm$, respectively. 2. Linear relationships were observed between venous pressure change and gastrointestinal tissue blood volume. The coefficients of correlation were: in spleen r=0.723; in liver r=0.791; in stomach r=0.704, respectively. In small intestine the relationship was less clear and r=0.358. Tissue blood volume of extrabdominal tissue, such as M. gastrocnemius was not influenced by venous pressure change. 3. The highest change in tissue blood volume expressed on weight basis was observed in spleen. The liver tissue showed the next highest change. Change in total tissue blood volume, however, was greatest in liver and next greatest in small intestine. This was interpreted by the fact that total weight of these two organs was much greater than that of spleen. 4. The mechanism that the change in tissue blood volume lies in the venous system which has a great compliance was discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1C
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• pp.27-35
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• 2012

The relieving platform has the advantage of decreasing the total lateral earth pressure on the retaining wall and increasing the overall stability of the structure. Several modeling tests were performed to determine the earth pressure distribution on the retaining wall with a relieving platform and to compare it with that of the cantilever retaining wall. Different types of soil and angle of cutting surface were used to determine the effect of the soil characteristics and the backfill conditions on these earth pressure distributions. From the modeling tests, comparisons between the retaining wall with a relieving platform and the cantilever retaining wall show that the reduction of the lateral earth pressure and deformation of wall was indicated clearly on the retaining wall with a relieving platform. And the overall stability was increased by the relieving platform.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.2
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• pp.181-191
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• 1991

The present study determined the overall noise level and the distribution of sound pressure level over audible frequency range of noise produced at various work sites. Work-related noise greater than 80dBA produced from 98 separate work sites at 37 manufacturing companies and machine shops were analysed for the overall sound level (dBA) and frequency distribution. In addition, to determine the possible hearing loss related to work site noise, a hearing test was also conducted on 1,374 workers in these work sites. The results of the study were as follows ; 1. Of the total 98 work sites, 57 work sites(58.2%) produced noise exceeding threshold limit value (${\geq}90dBA$) set by the Ministry 01 Labor. In terms of different manufacturing industries the proportion of work sites which exceeded 90dBA was the highest for the cut-stone products industry with 6/6 work sites and lowest for the commercial printing industry with 1/13 work sites. 2. The percentage of workers who were exposed to noise greater than 90dBA was 19.8% (1,040 workers) 01 the total 5,261 workers. In terms of different industries, cut-stone products industry had the most workers exposed to noise exceeding 90dBA with 82.8%, textile bleaching and dyeing industry was next at 30.6% followed by fabricated metal products industry with 27.9%, plastic products manufacturing industry had the lowest percentage of workers exposed to 90dBA exceeding noise with 4.5%. 3. There was a statistically significant correlation between the frequency of noise-induced hearing loss and the percentage of workers exposed to noise exceeding 90dBA (P<0.05). 4. The frequency analysis of noise produced at the 98 work sites revealed that 44 work sites (44.9%) had the maximum sound pressure level at high-frequencies greater than 2KHz. In addition, significantly higher sound pressure level was detected at the high-frequencies at 90dBA exceeding work sites as compared to below 90dBA work sites (P<0.01). 5. The differences in sound level meter's A-and C-weighted sound pressure levels were analysed by frequencies. Of the 28 work sites which showed 0-1 dB difference in the two weighted sound levels, 20 work sites (71.4%) had significantly higher sound pressure levels at high-frequencies greater than 2KHz (P<0.01). Furthermore, there was a tendency for higher sound pressure levels to occur in the high-frequency range as the differences in the two weighted sound levels decreased.

• International Journal of Fluid Machinery and Systems
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• v.2 no.1
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• pp.13-20
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• 2009

The effects of positively bowed blade on the aerodynamic performance of annular compressor cascades with large camber angle were experimentally investigated under different incidences. The distributions of the exit total pressure loss and secondary flow vectors of compressor cascades were analyzed. The static pressure was measured by tapping on the cascade surfaces, and the ink-trace flow visualizations were conducted. The results show that the value of the optimum bowed angle and optimum bowed height decrease because of the increased losses at the mid-span with the increase of the caber angle. The C-shape static pressure distribution along the radial direction exists on the suction surface of the straight cascade with large r camber angles. When bowed blade is applied, the larger bowed angle and larger bowed height will further enhance the accumulation of the low-energy fluid at the mid-span, thus deteriorate the flow behavior. Under $60^{\circ}$ camber angle, flow behavior near the end-wall region of some bowed cascades even deteriorates instead of improving because the blockage of the separated flow near the mid-span keeps the low-energy fluid near the end-walls from moving towards the mid-span region, and as a result, a rapid augmentation of the total loss is easy to take place under large bowed angle. With the increase of camber angle, the choice range of bowed angle corresponding to the best performance in different incidences become narrower.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.202-212
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• 2008

A three-dimensional computation was conducted to understand effects of the low Reynolds number on the loss characteristics in a transonic axial compressor, Rotor67. As a gas turbine becomes smaller in size and it is operated at high altitude, the operating condition frequently lies at low Reynolds number. It is generally known that wall boundary layers are thickened and a large separation occurs on the blade surface in axial turbomachinery as the Reynolds number decreases. In this study, it was found that the large viscosity did not affect on the bow shock at the leading edge but significantly did on the location and the intensity of the passage shock. The passage shock moved upstream towards leading edge and its intensity decreased at the low Reynolds number. This change had large effects on the performance as well as the internal flows such as the pressure distribution on the blade surface, tip leakage flow and separation. The total pressure rise and the adiabatic efficiency decreased about 3% individually at the same normalized mass flow rate at the low Reynolds number. In order to analyze this performance drop caused by the low Reynolds number, the total pressure loss was scrutinized through major loss categories such as profile loss, tip leakage loss, endwall loss and shock loss.

• Journal of Acupuncture Research
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• v.26 no.5
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• pp.1-10
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• 2009

Objectives : This study was conducted to investigate how Bone Mineral Density(BMD) and bone mass index(BMI) differ according to classification of blood pressure which JNC 7(The seventh report of the joint national committee on prevention, detection, evaluation and treatment of high blood pressure) indicated. Methods : We measured BMD and BMI of lumbar spine($L_2-L_4$) and femoral neck of 9816 people, and then we analyzed them according to classification of blood pressure. Results : The number of prehypertension group was the most, and Stage 2 hypertension group was the least. As the hypertension was increasing, BMD of lumbar and femoral neck were decreasing, and BMI was increasing. In men, as the blood pressure was increasing, BMI was increasing. But the BMD was irrelevant. In women, the distribution was similar to the total. Conclusions : As the hypertension was increasing, BMI was increasing and BMD was decreasing. And it was more remarkable in women.