• The Korean Journal of Physiology
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• v.11 no.2
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• pp.45-50
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• 1977

The maximum voluntary ventilation (MVV) is one of the most widely used pulmonary function test, but its measuring method was very difficult and unreliable. However, it is need to get more easy and simple measuring method of MVV. Therefore, this study was attempted to get more easy and simple measuring method of MVV by means of the forced expiratory volume $(FEV_{T})$. The young and healthy 1,000 Korean students(592 male and 408 female) were cheesed for this purpose and whose ages were from 8 to 20 years. A spirometer (9L, Collins Co.) was used for the MVV and FEV, and they were measured 3 times at standing position, and the highest value was used. In the measurements, the subjects for MVV were asked for the breath as fast and deeply as possible for 12 seconds, and for FEV were asked for the rapid and forceful exhalation after a maximal inhalation (forced expiratory curve). In the FEV measurements toward the end of the expiration, the subjects were exhaused to continue the effort until no further gas was expired. During these measurements, the investigator stood by the subject to give a constant encouragement. FEV were calculated in the volume exhaled during the one-half $(FEV_{0{\cdot}5,}\;ml)$, the first second $(FEV_{1{\cdot}0,}\;ml)$ and the percentage of the total vital capacity exhaled during the one-half second $(FEV_{0{\cdot}5,}\;%)$. The results are summarized as follows: 1) The values of MVV were increased linearly with ages until 20 in both sexes. The values of male at the age of 20 was $168.2{\pm}2.5L/min$, and female at the age of 17 was $112.3{\pm}3.0L/min$, respectively. 2) The values of FEV (ml) were increased linearly with ages until 20 in both sexes. The values of $FEV_{0{\cdot}5}$ were $2,797{\pm}65.7ml$ in the male of 20 years and were $2,088{\pm}54.6ml$ in the female of 17 years, and of $FEV_{1{\cdot}0$ were $4,119{\pm}68.2ml$ in the male of 20 years and were $2,897{\pm}65.9ml$ in the female of 17 years, respectively. 3) The correlation coefficients between MVV and $FEV_{0{\cdot}5}\;or\;FEV_{1{\cdot}0$ (ml) were 0.82 or 0.85 in the male, and 0.77 or 0.79 in the female, respectively. 4) The prediction formulae for MVV to be derived from above results were: For male: MVV (L/min) =7.19+$0.05{\times}FEV_{0\cdot5}(ml)$, MVV (L/min)=11.25+$0.04{\times}FEV_{1\cdot0}(ml)$ For female: MVV (L/min)=16.03+$0.05{\times}FEV_{0\cdot5}(ml)$, MVV (L/min)=9.47+$0.03{\times}FEV_{1\cdot0}(ml)$.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.562-570
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• 1996

A weight control program has been prescribed to investigate its effects on weight reduction of obese adults. The prescribed weight control program has been followed by 4 overweight adults and fad diets has been followed by 6 ovenveight adults for 3 to 7 months. The prescribed weight control program was basically the low calorie diet (1,500-1,800 kcal per day) and nutrition education was applied to enhance its effects. Fad diets were chosen among the fashionable diets and they were "apple diet" , "yogurt diet" and "Lee Hijae diet" Anthropometric measurements, biochemical parameters, and percent of body fat were measured after the respective period of weight control program. Body weight was significantly (p<0.01) reduced and the rate of obesity was also significantly lowered with the prescribed weight control program while the body weight and rate of obesity were not changed with the fad diets. Weight loss from the prescribed weight control program also led to the change of total cholesterol levels while LDL-cholesterol, HDL-cholesterol, triglyceride were not significantly changed. Nutrition education and counseling of the weight control subjects induced more weight loss and better food behavior. It is suggested that a weight loss program should be based on the low calorie diet with the well-planned nutrition education The fashionable diets were attractive for a short time period in weight reduction but the rapid weight gain was noticed right after the diets ceased.

• Korean Journal of Remote Sensing
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• v.30 no.3
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• pp.399-415
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• 2014

The intensity of stormwater runoff is particularly acute across cities located in arid climates. During flash floods loose sediment and pollutants are typically transported across sun-hardened surfaces contributing to widespread degradation of water quality. Rapid, dense urbanization exacerbates the problem by creating continuous areas of impervious surfaces, perforated only by a few green patches. Our work demonstrates how the latest techniques in remote sensing can be used to routinely measure urban land cover types, impervious cover, and vegetated areas. In addition, multiple regression models can then infer relationships between urban land use and land cover types with stormwater quality data, initially sampled at discrete monitoring sites, and then extrapolated annually across an arid city; in our case, the city of Phoenix in Arizona, USA. Results reveal that from 30 storm event samples, solids and heavy metal pollutants were found to be highly related with general impervious surfaces; in particular, with industrial and commercial land use types. Repercussions stemming from this work include support for public policies that advocate environmental sustainability and the more recent focus on urban livability. Also, advocacy for new urban construction and re-development that both steer away from vast unbroken impervious surfaces, in place of more fragmented landscapes that harmonize built and green spaces.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.11
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• pp.2292-2300
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• 2011

Exact and rapid acquirement of ocean environment information is going to become more of an indispensable source of naval operations. Ocean surface measurements using High Frequency (HF) radar, which covers about 10-220km and has spatial resolution of 0.3-12km, have being operated in our country. It remotely observe and transmit realtime sea surface currents and waves. In the near future, the HF radar systems will be established along the whole coastal area. A performance of network of HF radar will support various marine and naval activities. Operational uses of HF radar for enhancing naval operation ability are suggested.

• Geomechanics and Engineering
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• v.23 no.3
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• pp.289-300
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• 2020

With the rapid development of the distributed strain sensing (DSS) technology, the strain becomes an alternative monitoring parameter to analyze slope stability conditions. Previous studies reveal that the horizontal strain measurements can be used to evaluate the deformation pattern and failure mechanism of soil slopes, but they fail to consider various influential factors. Regarding the horizontal strain as a key parameter, this study aims to investigate the stability condition of a locally loaded slope by adopting the variable-controlling method and conducting a strength reduction finite element analysis. The strain distributions and factors of safety in different conditions, such as slope ratio, soil strength parameters and loading locations, are investigated. The results demonstrate that the soil strain distribution is closely related to the slope stability condition. As the slope ratio increases, more tensile strains accumulate in the slope mass under surcharge loading. The cohesion and the friction angle of soil have exponential relationships with the strain parameters. They also display close relationships with the factors of safety. With an increasing distance from the slope edge to the loading position, the transition from slope instability to ultimate bearing capacity failure can be illustrated from the strain perspective.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.3
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• pp.41-46
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• 2017

In this study, rapid cooling method was proposed to improve the anti-scratch performance of anti-reflection film fabricated by nanoimprint lithography. Effects of cooling time on the mechanical properties and optical properties were evaluated. Pencil hardness measurements showed that anti-scratch performance enhanced as the cooling time increased while characterization on the optical property showed that reflectance on scratch increased as the cooling time increased. Therefore, it was concluded that the anti-scratch performance and optical properties are highly influenced by the cooling time. The observed results explained in terms of residual stress and free volume in polymeric materials.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.4
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• pp.598-617
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• 2013

This study analyzes the body sizes of young boys in order to categorize a sizing system for middle and high school uniforms. The study was based on the $6^{th}$ National Anthropometric Survey (Size Korea 2010) data. The sample size consisted of 2,317 boys between the ages of 13 and 18 years. Most measurement items increased significantly relative to age and there was rapid growth between the ages of 13 and 14 years. The growth for the chest and hip was more than the waist. The drop value 1 (difference between chest circumference and waist circumference) and the drop value 2 (difference between hip circumference and waist circumference) increased remarkably from the age of 13 to the age of 15. Therefore, the waist size decreased and chest and hip became wider relative to the age increase. Middle school students had a smaller chest and hip circumference than high school students in the comparative body measurement results for middle school students (13-15 years) and high school students (16-18 years) of the same height group. The somatotype of high school students showed a long trunk length, broad chest and shoulder.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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• pp.500-507
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• 2004

This study was conducted to evaluate the equity of the flow distribution from rapid mixing basin to the flocculation basins. Also, several types of inlet structures of the open channel affecting the flow pattern and distribution trend were studied using Computational Fluid Dynamics (CFD) simulation. For investigating the factual phenomena in distribution channel, we selected a certain domestic water treatment plant with capacity of $361,000m^3/d$. From the measurements of flow discharge, it is investigated that this existing inlet geometry resulted in significant inequitable distribution. The both largest deviations in the basins and rows were over 10%. In order to reduce the these deviation, this study suggested installing a baffle against the influent, and showed the effectiveness which the largest deviation was less than 3%. Also, it was concluded that the existing design method of open channel could be improved by three-dimensional hydrodynamic analysis for optimizing the even flow.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.288-294
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• 2017

This paper contains results of the theoretical studies of the electrical breakdown properties in sulfur hexafluoride. Since the strong interaction of high-energy electrons with the polyatomic sulfur hexafluoride molecule causes their rapid deceleration to the lower energy of electron capture and dissociative attachment, the breakdown is only possible at relatively high field strengths. From the breakdown voltage curves, the effective yields that characterize secondary electron productions have been estimated. Values of the effective yields are found to be more consistent if they are derived from the experimentally determined values of the ionization coefficient and the breakdown voltages. In addition, simulations were performed using an one-dimensional Particle-in-cell/Monte Carlo collision code. The obtained simulation results agree well with the available experimental data with an error margin of less than 10% over a wide range of pressures and the gap sizes. The differences between measurements and calculations can be attributed to the differences between simulation and experimental conditions. Simulation results are also compared with the theoretical predictions obtained by using expression that describes linear dependence of the breakdown voltage in sulfur hexafluoride on the pressure and the gap size product.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.10
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• pp.885-890
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• 2015

Walking on split-belt treadmill has been applied to study walking disabilities, such as osteoarthritis (OA), to show asymmetric walking characteristics. In this study, we compared asymmetric walking in OA patients with healthy subjects under split-belt conditions and examined the reproduction of walking asymmetry in OA. Seven OA patients were instructed to walk at four frequencies, while four healthy subjects walked on a treadmill with tied-belt and split-belt conditions. To compare walking asymmetries, kinetic and kinematic measurements were made using force-plates and motion capture cameras, and subsequently center of mass (CoM) velocity, mechanical work and potential energy were calculated. Horizontal velocity change during split-belt walking of healthy subjects was similar to OA patients. Difference of mechanical work during single support phase occurred due to fall of CoM in fast belt. OA walking asymmetry could be reproduced by reducing differences of belt speeds to prevent rapid fall of CoM.