• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.6
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• pp.468-477
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• 2014

In this research, how a solar powered HALE (high altitude long endurance) UAV (Unmanned Aerial Vehicle) can climb and reach mission altitude, 18km, starting from the ground using only solar energy. A glider type aircraft was assumed as a baseline configuration which has wing area of $35.98m^2$ and aspect ratio of 25. Configuration parameters, lift and drag coefficients were calculated using OpenVSP and XFLR5 that are NASA open source programs, and climb flights were predicted through energy balance between available energy from solar power and energy necessary for a climb flight. Minimum time climb flight was obtained by minimizing flight velocities at each altitude and total time and total energy consumption to reach the mission altitude were predicted for different take off time. Also, aircraft moving distances due to westerly wind and flight speed were calculated.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.220-224
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• 2005

The purpose of the present study is to investigate the effects of long-term exercise program on exercise capacity and cognitive function (MMSE) in male patients with dementia. 24 male patients were divided into two experimental groups : the exercise group (n=12) and the control group (n=12). The exercise group participated in regular exercise program for 12 months, and their exercise capacity (cardiopulmonary function, muscle strength, muscular endurance, flexibility, balance, agility) and MMSE (Mini-mental state examination) levels were evaluated at baseline (pre), after 6 months (mid) and after 12 months (post). The subjects carried on group-exercise of $VO_{2}max\;30\~60\%$, $30\~60$ minute a day, $2\~3$ times per week. Statistical techniques for data analysis was paired samples t-test. The level of statistical significance was ${\le}.05.$ The results of this study were summarized as follows: In the exercise group, there were significant differences in cardiopulmonary function, muscle strength, muscular endurance and MMSE at the times of pre & mid and pre & post, there were significant differences in balance and agility at the time of pre & post only, whereas there was no significant difference in flexibility following the long-term exercise. In the control group, there were no significant differences in all the times. Based on the results of this particular study, one year exercise program increases on the cognitive function & exercise capacity in male patients with dementia.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.3
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• pp.68-73
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• 2014

Research is being carried out at Korea Aerospace Research Institute with aim of design a HALE UAV(High Altitude Long Endurance Unmanned Air Vehicle). HALE UAVs are ideally suited to provide surveillance, remote sensing and communication relay capabilities for both military and civilian applications. HALE UAVs typically cruise at an altitude between 15 km and 20 km, travelling at low speed and circling specific area of interest. Airframe structural point of view, weight reduction of the airframe structure is the most important method to improve the flight efficiency. High modulus CFRP(Carbon Fiber Reinforced Polymer) has been used in designing the structure in order to minimize the airframe weight. With respect to structural design and analysis, the key question is to decide an adequate airworthiness certification base to define suitable load cases for sizing of various structural components. In this study, FAR(Federal Aviation Regulation) 23 have constituted the guidance and benchmark throughout all structural studies. And the MSC/FlightLoads was introduced to analyze the flight loads for the HALE UAV. The MSC/FlightLoads can compute the flexible air load and analyzed loads are distributed on structural model directly. A preliminary structural concept was defined in accordance with the estimated inertial and aerodynamic loads. A FEM analysis was carried out using the MSC/Nastran code to predict the static and dynamic behaviour of UAV structure.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.523-535
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• 2012

Solar powered aircraft are becoming more and more interesting for future long endurance missions at hight altitudes, because they could provide surveillance, earth monitoring, telecommunications, etc. without any atmospheric pollution and hopefully in the near future with competitive costs compared with satellites. However, traditional aircraft sizing methods currently employed in the conceptual design phase are not immediately applicable to solar powered aircraft. Hence, energy balance and constraint analyses were performed to determine how various power system components effect the sizing of a solar powered long endurance aircraft. The primary power system components considered in this study were photovoltaic (PV) modules for power generation and regenerative fuel cells for energy storage. To verify current research results, these new sizing methods were applied to HALE aircraft and results were presented.

• Journal of the Korean Applied Science and Technology
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• v.5 no.2
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• pp.39-54
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• 1988

The effects of exercise and selenium added high fat diet on edurance and serum lipid components were studied in rats. A total of 72 male Sprague-Dawley ($150{\pm}35g$, body weight) were divided into trained group and untrained group and were bred for 7 weeks. Each group had 6 different dietary subgroups; namely, basal diet, 20％ shortening and 20％ soybean oil subgroup and selenium (0.01mg％) added each subgroups. Exercises of 8-min treadmill running and 10-min swimming were given to the trained group every other day during the experimental period while only treadmill running was given to the untrained group during the last week. The amounts of food intake, changes in body weight and endurance were determined once a week and serum lipid components were measured before and after experimental period. Following are the results obtained : 1) The untrained group took a slightly larger amount of food than that in the trained group. The food efficiency is, however, higher in the trained group. Body weight increased more in untrained group, while high fat diet resulted in greater increment in body weight than that in normal diet groups. 2) The trained group showed remarkably longer endurance than the untrained group and selenium added high fat diet enhanced the effect. 3) The trained group showed lower blood level of T-chol., TG and TG/PL than the untrained group. All the other blood values of HDL-chol., PL, MDL-chol./T-chol., HDL/LDL and A/G ratio were higher in trained group. 4) Soybean oil added dietary groups exibited lower blood levels of T-chol., TG, TG/PL and A/G than those in shortening added dietary groups. On the contrary, the former groups showed higher blood HDL-chol., PL., HDL, HDL-chol. and HDL/LDL ratio than those of soybean oil added dietary groups. 5) $LDH_5$ was the most abundant one among serum LDH isozymes. The electrophoretic pattern of serum LDH isozymes was not changed by exercise training and selenium added high fat diet. 6) Exercise training lowered blood GOT and TBA. These effects were enhanced by soybean oil added diets. From the above results it was concluded that a regular and long term exercise training as well as a small amount of selenium added high fat diet result in reduction of body weight and TBA and improve dietary efficiency and physical endurance in rats.

• Korean Security Journal
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• no.14
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• pp.431-447
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• 2007

The purpose of this study was to investigate the An analysis on the physical strength factor of the Collegians majoring in Security Services. In order to accomplish this purpose, subjects of this study were 80 person J university student men. Physical fitness tests was grip strength, back strength, sit-ups, stand long jump, 50m run, side step test, shuttle run, 2000m run, standing trunk flexion, and closed eye foot balance. Factor analysis applied for analysis factorial structure of each physical fitness components. The results of this study were as follow; First, the factor affecting the performance of the Collegians majoring in Security Services of their was appeared with the Power, Balance and Strength. Second, the factor affecting the performance of the Collegians majoring in Security Services of their was appeared with the Taekwondo major group with the Balance, Power, Strength and Cardiovascular Endurance. Third, the factor affecting the performance of the Collegians majoring in Security Services of their was appeared with the Judo major group with the Power, Flexibility and Strength. Fourth, the factor affecting the performance of the Collegians majoring in Security Services of their was appeared with the Hapkido major group with the Muscular Endurance, Strength, Cardiovascular Endurance and Flexibility. Fifth, the factor affecting the performance of the Collegians majoring in Security Services of their was appeared with the Gumdo major group with the Cardiovascular Endurance and Power.

• Development and Reproduction
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• v.5 no.1
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• pp.73-79
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• 2001

Recently many studies have reported that total and bioavailable androgens reduced in male and female athletes and that physical exercise reduces the body weight and increases the reproductive abnormalities such as oligomenorrhea, anovulation, inadequate luteal phase, and delayed puberty in women by the inhibition of the hypothalamic-pituitary-gonadal (HPG) axis . In addition, high mileage endurance 겨nning, psychological stress, and military endurance training in men also reduce the secretion of reproductive hormones. To investigate the efffcts of physical endurance exercise on the secretion of reproductive hormones in men, androgenic hormones from adrenal glands and testis were measured in serum by the conventional radioimmunoassays after long-term (more than3 months), short-term (1 week), and acute (1${sim}$2 hours) physical exercises. Androgenic hormones from adrenal glands and testis such as total testosterone (TT), free testosterone (fT), dehydroepiandrosterone (DHEA), and androstenedione (A) decreased after thesestrenuous endurance trainings, whereas ACTH, cortisol, and dehydroepiandrosterone sulfetes (DHEAS) increased. Conadotropins (LH and FSH) were not idluenced by the physical exercises. Based upon the present results, we assume that the decrease in adrenal and testicular androgens by physical endurance exercises might be associated with the reproductive abnormalities in athletes by unknown factor(s) in addition to the HPG axis disturbance.

• Journal of Conservation Science
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• v.5 no.1 s.5
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• pp.94-104
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• 1996

This study was carried on paper mulberry bast fibers, which were cut in the length of it's chip by three kinds. And they cooked by sodium hydroxide (NaOH) and ammonium oxalate (AMOX), and pulping process was studied to inquire some properties of hand made papers. The results were as follows. AMOX pulps had $10\~17\%$ higher than NaOH, but amounts of the residual lignin of it's pulps and residual ash were high, and it surely can't be superior. In the freeness of pulps, AMOX pulps were higher than that of NaOH, but they showed tendency to opposite in view of relation of chip's length kinds. For the AMOX pulps, the physical characteristics test results were higher long fiber pulps than short fiber pulps. Specially, in folding endurance long fiber pulps were a very strong. NaOH pulp's physical characteristics test had shown results that were opposite of there of the AMOX pulps, if the length of the fiber is longer, the strengthts generally decreased. To get the optimum fiber's length according to use of paper and pulping method, they must be fractionate chip's length. The long fibers in NaOH pulps affected the paper quality greatly to length of chips.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.3
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• pp.55-62
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• 2015

Paper mulberry fibers have been used as fibrous raw materials for manufacturing traditional handmade paper, hanji for a long time. Compared to wood pulp fibers, pulp fibers from mulberry bast tissue have some benefits in physical and chemical properties due to their high D.P (degree of polymerization), M.W (molecule weight) and long fiber length. Specially, Korean handmade hanji shows outstanding characteristics in mechanical tensile strength, folding endurance, flexibility and long sustainable conservation properties. Therefore, hanji is widely applied to daily supplies, hygienic goods, medical supplies, clothing industries and so on. Recently, the potential demand of mulberry pulp fibers is more and more increased on the strength of high application fields. This study was focused on the possibility of wastewater recycling in unit operation systems for the development of automated mass production line. The properties and environmental loads of wastewater from debarking, cooking, bleaching and screening process were analyzed by means of COD, conductivity, turbidity and solid materials. The wastewater from debarking and cooking process was comparatively high in pollution load, and would be treated by additional approaches of chemico-physical method.

• Tuberculosis and Respiratory Diseases
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• v.81 no.1
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• pp.13-18
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• 2018

Bronchodilator therapy is central to the management of chronic obstructive pulmonary disease and are recommended as the preferred treatment by the Global Obstructive Lung Disease Initiative (GOLD). Long acting anti-muscarinics (LAMA) and long acting ${\beta}_2$ agonists (LABA) are both more effective than regular short-acting drugs but many patients remain symptomatic despite monotherapy with these drugs. Combination therapy with LAMA and LABA increases the therapeutic benefit while minimizing dose-dependent side effects of long-acting bronchodilator therapy. The TOviTO programme has investigated the benefits of treatment with a combination of tiotropium and olodaterol administered via a single inhaler. Tiotropium+olodaterol $5/5{\mu}g$ significantly improved forced expiratory volume in 1 second ($FEV_1$) area under the curve from 0 to 3 hours, trough $FEV_1$ health status and breathlessness versus the mono-components and placebo. Tiotropium+olodaterol $5/5{\mu}g$ also increased endurance time and reduced dynamic hyperinflation during constant work rate cycle ergometry. On the basis of these and other studies the 2017 GOLD report recommends escalating to dual bronchodilator therapy in patients in groups B and C if they remain symptomatic or continue to have exacerbations and as initial therapy for patients in group D.