• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.3
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• pp.493-498
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• 2016

Heart Rate Variability (HRV) represents beat-to-beat fluctuations of R-R intervals in Electrocardiogram (ECG). On of the clinical applications of HRV is to assess the mental-stress state by evaluating its power spectral density distribution. This study aims at finding new discriminative role of the coupled-oscillating coupling constants, Cs and Cp in the Integral Pulse Frequency Modulation (IPFM) model. Based on comparing with power spectral density of HRV in terms of the relative ratio of the low and high-frequency power component, we can conclude the fact that the coupling parameters Cs and Cp can replace the role of HRV power spectrum interpretation for judging the mental-stress state.

• Journal of the Korean Dietetic Association
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• v.15 no.4
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• pp.343-355
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• 2009

To elucidate the effect of a 4 week dietary supplementation with pumpkin water extract on serum lipid and fasting glucose levels, 41 female collegians residing in the Gyeonggi area were recruited. The subjects were divided into three groups: placebo-control (PC, n=11), treatment A (TA, 100 ml/day, n=13), and treatment B (TB, 300 ml/day, n=17). Total serum cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride (TG), and fasting glucose were analyzed. The average age, height, weight, and body mass index of the subjects were 21.3 years, 161.1 cm, 53.0 kg, and 20.4 $kg/m^2$, respectively. The average total cholesterol, HDL-cholesterol, LDL-cholesterol, TG, and fasting glucose level (mg/dl) were 171.4${\pm}$26.1, 63.5${\pm}$11.4, 92.6${\pm}$22.9, 76.8${\pm}$32.0, and 89.1${\pm}$8.2, respectively. There were no significant differences among the three groups in any measured parameters, and between the pre- and post-study values of the all parameters. The results indicated that the 4 week pumpkin water extract supplementation (100 ml, 300 ml) did not influence the serum total cholesterol, HDL-cholesterol, LDL-cholesterol, TG and fasting glucose level in female collegians.

• Journal of the Korean Solar Energy Society
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• v.38 no.2
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• pp.1-13
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• 2018

This paper deals with the NREL (National Renewable Energy Laboratory) 5-MW reference wind turbine. The controller which include MPPT (Maximum power point tracking) control algorithm and tower load reduction control algorithm was designed by MATLAB Simulink. This paper propose a tower damper algorithm to improve the existing tower damper algorithm. To improve the existing tower damper algorithm, proposed tower damper algorithm were applied the thrust sensitivity scheduling and PI control method. The thrust sensitivity scheduling was calculated by thrust force formula which include thrust coefficient table. Power and Tower root moment DEL (Damage Equivalent Load) was set as a performance index to verify the load reduction algorithm. The simulation were performed 600 seconds under the wind conditions of the NTM (Normal Turbulence Model), TI (Turbulence Intensity)16% and 12~25m/s average wind speed. The effect of the proposed tower damper algorithm is confirmed through PSD (Power Spectral Density). The proposed tower damper algorithm reduces the fore-aft moment DEL of the tower up to 6% than the existing tower damper algorithm.

• Journal of the Korean Dietetic Association
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• v.2 no.1
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• pp.38-48
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• 1996

The relationship of nutrients intake and bone mineral density (BMD) was investigated in 285 Korean postmenopausal women (age 40-70 y) consisted of 65 normal women and 159 osteopenia patients who don't have other diagnosed disease. BMD was measured at the spine (vertebrae L2-4) and femur (neck, Ward's triangle and trochanter). Height, weight, body mass index(BMI), lean body mass(LBM), body fat(Bfat) and dietary intakes of animal calcium(animal Ca), protein and phosphorus per 1,000kcaI intake were correlated with BMD of the spine and the femur positively(p<0.05). Women with an animal calcium intake < 315mg/d (mean % animal Ca/total Ca intake > 50%) exhibited significantly lower BMD of the spine and Ward's triangle than that of women with an intake > 315mg/d, p<0.OS. When subjects were grouped by diagnosis into 3 groups (normal, osteopenia and osteoporosis group), animal Ca intake of osteoporosis group (mean animal Ca intake 261mg) was significantly lower than those of the other two groups (mean animal Ca intake 306mg and 297mg, respectively), p < 0.05. These results suggest that balanced nutrients intake and increased animal Ca in the diet is likely to be beneficial in reducing bone loss in postmenopausal women.

• Journal of the Korean Chemical Society
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• v.64 no.5
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• pp.259-266
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• 2020

The main purpose of this study is to examine the different physicochemical properties of spray-dried products. The carrier agents and powders after the spray-drying process were analyzed for encapsulation yield, moisture content, color parameters, total polyphenol content (TPC), antioxidant capacity (AC), bulk density, flowability, wettability, hygroscopicity, water solubility index (WSI), particle size and microstructure. The spray-drying process was carried out with different carrier agents including maltodextrin (MD) and the combination of maltodextrin and gum arabic (MD-GA) with MA/GA ratio of 70/30, dried at the inlet/outlet air temperature of 160 ℃/70 ℃, 4 bar, airflow rate of 70 ㎥·h^-1 and feed flow rate of 750 mL·h^-1. The results showed that the different carrier agents have significant influences on the physicochemical properties of the powder produced by the spray-drying method. In there, while the values of recovery efficiency and flowability of spray-dried products from MD are higher than those of spray-dried products from MD-GA combination, the opposite is true for the values of TPC, AC, bulk density and wettability, whereas hygroscopicity and WSI values are equally represented in both products.

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.205-211
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analy zing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha, of which IVF accounted for 316.8ha(71.5$\%$), the largest portion, secondary vegetation for 101.2ha(22.8$\%$), IVA for 6.2ha(1.4$\%$), and others for 19.1ha(4.3$\%$). The ratio of natural forest elements of 31.9$\%$ showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• Transactions on Electrical and Electronic Materials
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• v.3 no.3
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• pp.34-38
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• 2002

In this paper, efficiency estimation of toxicity fee fire resistance cable experiments was measured smoke density of toxicity free fire resistance polyolefin insulation material and electric field dependence of tree shape in low density polyethylene (LDPE). One of the most serious causes of failure in high-voltage cables, can be an electrical discharge across an internal gab or void in the insulating material. Treeing due to partial discharge is one of the main causes of breakdown in the insulating materials and reduction of the insulation life. Therefore the necessity for establishing a method to diagnose the aging of insulation materials and to predict the breakdown of insulation and research of the fire resistance character has become important. First, we have studied on electric field dependence of tree shape in LDPE about treeing phenomena occurring on the high electrical field. Second, the measurement method is the attenuation quantity of irradiation by smoke accumulating with in a closed chamber due to non-flaming heat decomposition and flaming combustion. A main cause of fire-growth and generating toxic gas when, it bums, should be dealt with great care in life. safety design. The fire gases were occurred carbon monoxide and decomposition than in polyolefin due to incomplete combustion of PVC, which has high content of carbon in chemical compound.

• Geomechanics and Engineering
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• v.19 no.4
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• pp.307-314
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• 2019

Light construction waste (LCW) particles are pieces of light concrete or insulation wall with light quality and certain strength, containing rich isolated and disconnected pores. Mixing LCW particles with soil can be one of the alternative lightweight soils. It can lighten and stabilize the deep-thick soft soil in-situ. In this study, the unconfined compressive strength (UCS) and its mechanism of Construction Waste Stabilized Lightweight Soil (CWSLS) are investigated. According to the prescription design, totally 35 sets of specimens are tested for the index of dry density (DD) and unconfined compressive strength (UCS). The results show that the DD of CWSLS is mainly affected by LCW content, and it decreases obviously with the increase of LCW content, while increases slightly with the increase of cement content. The UCS of CWSLS first increases and then decreases with the increase of LCW content, existing a peak value. The UCS increases linearly with the increase of cement content, while the strength growth rate is dramatically affected by the different LCW contents. The UCS of CWSLS mainly comes from the skeleton impaction of LCW particles and the gelation of soil-cement composite slurry. According to the distribution of LCW particles and soil-cement composite slurry, CWSLS specimens are divided into three structures: "suspend-dense" structure, "framework-dense" structure and "framework-pore" structure.

• Journal of Korean Medicine for Obesity Research
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• v.17 no.2
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• pp.140-144
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• 2017

A highly obese female patient (body mass index=$30.8kg/m^2$) participated in a 10-day Gamrosu modified fasting therapy with soluble dietary fiber supplementation to enhance lipid metabolism. Gamrosu is a modified fasting therapy beverage which is made from medical herbs and carbohydrates (431 kcal/d). Before and after fasting, we evaluated the efficacy of therapy by measuring the changes of body composition and blood chemistry. After the modified fasting therapy, -6.1% of body weight and -5.6% of body fat mass were decreased. With regard to blood chemistry, all the plasma lipid levels were lowered. -37.4% of total cholesterol, -39.7% of low density lipoprotein cholesterol, -39.0% of triglyceride and -27% of high density lipoprotein (HDL) cholesterol were reduced. Further studies are needed to alleviate the reduction of HDL-cholesterol to apply the Gamrosu modified fasting to hyperlipidemia.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.95-105
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• 2021

Extensive groundwater abstraction has been recognized as one of the major challenges in management of coastal groundwater. The purpose of this study was to assess potential changes of groundwater distribution of northeastern Jeju Island over 10-year duration, where brackish water have been actively developed. To quantitatively estimate the coastal groundwater resources, numerical simulations using three-dimensional finite-difference density-dependent flow models were performed to describe spatial distribution of the groundwater in the aquifer under various pumping and recharge scenarios. The simulation results showed different spatial distribution of freshwater, brackish, and saline groundwater at varying seawater concentration from 10 to 90%. Volumetric analysis was also performed using three-dimensional concentration distribution of groundwater to calculate the volume of fresh, brackish, and saline groundwater below sea level. Based on the volumetric analysis, a quantitative analysis of future seawater intrusion vulnerability was performed using the volume-based vulnerability index adopted from the existing analytical approaches. The result showed that decrease in recharge can exacerbate vulnerability of coastal groundwater resources by inducing broader saline area as well as increasing brackish water volume of unconfined aquifers.