• Journal of Korean Society for Atmospheric Environment
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• v.19 no.3
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• pp.285-296
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• 2003

The measurement of the radiation energy, trunk temperature, leaf area index (LAI), air temperature, vapor pres-sure, and precipitation has been conducted under a mixed forest at Kwangneung Arboretum during the period of 2001. Characteristics of the diurnal and seasonal variation of the radiative energy were investigated. The aerodynamic roughness length was determined as about 1.6 m and the mean albedo was about 0.1 The downward short-wave radiation was linearly correlated with the net radiation and its correlation coefficient was about 0.96. From this linear relation, the heating coefficient was calculated and its annual mean value was about 0.21 The albedo and heating coefficient was varied with season, surface characteristics, and meteorological conditions. The diurnal and seasonal variations of radiation energy were discussed in terms of the surface characteristics and meteorological conditions. In the daytime, during clear skies, net radiation was dominated by the shortwave radiation. In presence of clouds and fog, the radiation energy was diminished. At night, the net radiation was entirely dominated due to the net longwave radiation. There was no distinct diurnal variation in net radiation flux during the overcast or rainy days. The net radiation was strongest in spring and weakest in winter. The seasonal development in leaf area was also reflected in a strong seasonal pattern of the radiation energy balance. The timing, duration, and maximum leaf area and trunk temperature were found to be an important control on radiation energy budget. The trunk temperature was either equal or warmer than air temperature during most of the growing season because the canopy could absorb a substantial amount of sunlight. After autumn (after the middle of October), the trunk temperature was consistently cooler than air temperature.

• Journal of the Korean Dietetic Association
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• v.14 no.4
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• pp.396-403
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• 2008

We attempted to determine whether energy density would influence calorie intake via cognitive cues, as reflected by satiety. This experiment was designed using two different energy density levels of Kimbab: normal Kimbab (1.6 kcal/g) vs low-density Kimbab (1.0 kcal/g). 26 female college students participated in this study. The subjects ate Kimbab in the lab once a week for 2 weeks. Each week at noon, they were served 24 units of either normal or low-density Kimbab, and we determined the units, grams, and calories of the real & cognitive intake of Kimbab, and also analyzed the satiety rate after eating Kimbab. Our results demonstrated that the real calorie intake from the low-density Kimbab was significantly lower than that of the normal Kimbab (290.3 kcal vs 474.4 kcal, p<0.001), but we noted no significant differences in the units and grams of real and cognitive intake between the normal and low-density Kimbab. However, despite consuming 39% lower caloric intake, the subjects reported similar levels of satiety rates with the two different density levels of Kimbab, as they did not perceive themselves to have eaten more normal Kimbab than low-density Kimbab. Thus, this study provides evidence that the energy density of food is a crucial determinant of caloric intake, and supports the notion that the consumption of low energy-dense foods may result in a reduction of caloric intake without altering satiety.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.1038-1047
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• 2008

This study aimed at targeting fixed increases in body weight (100 g/wk) by quantitatively regulating energy allowances (ME) in broiler breeders from 5 to 20 wks of age. Four energy regimes were tested: 1. The energy required for maintenance, activity and growth was calculated for 100 g increases in body weight/wk and a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) was offered to the control group (ME-100) to achieve the anticipated weight gain. The energy allowances increased with age from 132 to 294 kcal/d. 2. Additionally, three energy regimes were considered, quantitatively reducing ME by 10% (ME-90) or 20% (ME-80) and increasing by10% (ME-110) over the control group. Each test group had 23 replicates5 female chicks housed in cages. The influence of energy regimes and age on growth, nutrient digestibility, carcass attributes, bone parameters and stress was evaluated at 4 wk intervals. Quantitative ME restriction by 10% (119-265 kcal/d) produced an average weight gain of 98.1 g/wk, which was closer to the targeted increase of 100 g/wk, whereas the control group attained it nine days earlier. Restriction of energy by 10 or 20% produced better conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P than 10% excess ME. Energy regimes did not influence eviscerated meat yield, but higher energy allowances (ME-110) significantly increased abdominal fat pad and liver weights and decreased giblet weight, percent muscle protein and tibia ash. Relatively higher stress was recorded in ME-restricted groups, as reflected by wider heterophil and lymphocyte ratios and increased bursa weight. Early age (5-12 wk) significantly influenced bone mineralization, conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P, while later ages (13-20 wk) increased eviscerated meat yield, abdominal fat, tibia weight and muscle protein and reduced stress. Energy regime x age interactions were significant and are discussed. In conclusion, the synthetic broiler line used in our study responded positively to controlled energy feeding during the rearing period. Breeders offered 119-265 kcal/d, a reduction of 10% energy over the control group, were more effective in regulating grower performance than the latter. In addition to energy regimes, age intervals also exhibited significant influence on specific parameters during the grower phase.

• Analytical Science and Technology
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• v.5 no.1
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• pp.135-142
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• 1992

Indium tin oxide(ITO) films coated on the window glass selectively transmit the solar energy and infrared. We call this system passive solar collectors. Selectively absorbing properties of sol gel dip coated ITO films were characterized by UV-VIS-NIR spectroscopy. The effects of heat treating temperature, time, atmosphere, substrate and barrier layers are concerned. Indium tin oxide films heat-treated at $500^{\circ}C$ in a reducing atmosphere show intrinsic properties. Efficiency of solar energy transmittance was enhanced by coating of $SiO_2-ZrO_2$ as an alkali ion barrier layer. Energy was saved by the double layers of $SiO_2-ZrO_2$ and ITO since solar energy is transmitted and heat generated inside(${\lambda}$ > 2700nm) is reflected.

• Journal of the Korean Electrochemical Society
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• v.12 no.1
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• pp.11-25
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• 2009

Fuel cells are expected to be one of the major clean new energy sources in the near future. However, the slow kinetics of electrocatalytic hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR), and the high loading of Pt for the anode and cathode material are the urgent issues to be addressed since they determine the efficiency and the cost of this energy source. In this review paper, a new approach was developed for designing electrocatalysts for the HOR and ORR in fuel cells. It was found that the electronic properties of Pt could be fine-tuned by the electronic and geometric effects introduced by the substrate alloy metal and the lateral effects of the neighboring metal atoms. The role of substrate was found reflected in a volcano plot for the HOR and ORR as a function of their calculated d-band centers. This paper demonstrated a viable way to designing the electrocatalysts which could successfully alleviate two issue facing the commercializing of the fuel cell-the cost of electrocatalysts and their efficiency.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.589-597
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• 2015

Wave energy harvesting system using OWC(Oscillating Water Column) and MB (Movable Body) attached at the caisson breakwater was studied. This system was suggested to maximize wave energy extraction using resonant phenomena of oscillating water column and buoy in wave channel (Park et al., 2014). Not only incident waves but also reflected waves from the breakwater can be used as sources of exciting force for harvesting wave energy efficiently. Using Galerkin finite model based on the linear wave theory (Park, 1991), the performance of the system was evaluated for various damping ratios of power take off system. Numerical results show that the proposed system is excellent in efficiency compared with that of conventional system and the performance of the system is governed by the resonance of oscillating water column in the wave channel. In addition, the additional efforts to minimize viscous damping was found to be necessary because viscous damping occurring in the channel and around the moving buoy is significant in generation efficiency.

• Journal of Science of Art and Design
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• v.10
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• pp.111-159
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• 2006

The study is to examine the concept, origin, developmental process, and characteristics of 'Kioonsangdong,' or 'lively energy' to look into whether 'Kioon' maybe interpreted by modern sense and sensitivity and be applied to contemporary creative activities, and to explore whether the ideality of 'Kioon' may be transferred into visualization in pictures. The article defines the scope of 'Ki' as 'Ki(energy)' of artistry and sees the Wei, Chin and the South & North dynasties as its derived point. In Chapter I, before the examination of 'Kioon,' 'the relationship of Ki and Oon,' and 'interrelationship of Kioon (energy) and Sangdong (liveliness) are investigated. It is impossible to define Kioon in a word due to its being abstract. Thus, although it does not seem to be unlimited, focusing on putting a variety of concepts of Kioonsangdong in order, it classifies the subject, from which such Kioon reveals itself, into 'its former self,' things of the object,' 'character,' and 'brush and Chinese ink.' Then, with selected representative works for each category, it examines how Kioonsangdong is reflected in the works. In addition, it comprehensively argues on Kioon through presenting the points of Kioon theories by many an art critic and artist from the Wei, Chin and the South & North dynasties to modem China. In Chapter II, the study analyzes the Kioon-reflected works that have been examined in Chapter 1 in the light of the Kioon theories of 'blanks,' 'styles of brushmanship,' and 'techniques of Chinese ink,' and by selecting and analyzing representative artists and works in each era, it investigates how Kioon had been transformed as times had changed. In Chapter III, which is the core of the study, is on contemporary interpretations of Kioon. I intend to interpret Kioon as scent. In other words, through replacing abstract Kioon with the olfactory sense, actually realizing and forming it, and then visualizing it onto my own work, I attempt to grope for contemporary interpretations of Kioon. That is to say, I explain how Kioon is transformed into scent on the grounds that the origins of Kioon may be detected in literature and aesthetics. Besides, the study looks into the process that 'the scent of the olfactory sense' turns into 'the scent of art,' which I assert by contemporary interpretations, and shows in details that it may be visualized in pictures presenting quotes. In Chapter IV, it analyzes Kioonsangdong expressed visually as the scent of art in my own work in terms of the three techniques of blanks, brushmanship, and Chinese ink.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.113-119
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• 2018

The probabilistic seismic safety assessment is one of the methodology to evaluate the seismic safety of the nuclear power plants. The site characteristics of the nuclear power plant should be reflected when evaluating the seismic safety of the nuclear power plant. The Korea seismic characteristics are strong in high frequency region and may be different from NRC Regulatory Guide 1.60, which is the design spectrum of nuclear power plants. In this study, seismic response of a nuclear power plant structure by Pohang earthquake (2017.11.15. (KST)) is investigated. The Pohang earthquake measured at the Cheongsong seismic observation station (CHS) is scaled to the peak ground acceleration (PGA) of 0.2 g and the seismic acceleration time history curve corresponding to the design spectrum is created. A nuclear power plant of the containment building and the auxiliary buildings are modeled using OPENSEES to analyze the seismic response of the Pohang earthquake. The seismic behavior of the nuclear power plant due to the Pohang earthquake is investigated. And the seismic performances of the equipment of a nuclear power plant are evaluated by the HCLPF. As a result, the seismic safety evaluation of nuclear power plants should be evaluated based on site-specific characteristics of nuclear power plants.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.727-732
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• 2001

The purpose of this study is to compare the time mean velocity distribution, the time mean kinetic energy, and the time mean turbulence intensity between vertical and horizontal flow fields in a coaxial circular pipe by PIV measurement. Experiments are performed at a Reynolds number 2,000, measuring regions divided as the section regions A, B, C, D in flow fields. The angle of the high-frequency ultrasonic is selected in the direction of $45^{\circ}$ to the flow axes and it is reflected several times. In results, it is clarified that the effect of gravity is given in the vertical flow field compared with the horizontal flow field and the ultrasonic affects the turbulence enhancement. And kinetic energy and turbulence intensity with ultrasonic are shown slightly bigger than those in flow field without it.

• Journal of Nutrition and Health
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• v.31 no.5
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• pp.957-964
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• 1998

The study was undertaken to assess the degree to which subjects were compliant with a specific metabolic diet in a controlled outpatient feeding study. The study consisted of a two-week control period in which subjects consumed a control diet consisting of 38-40% fat, 18-20% protein, 40-42% carbohydrate, followed by a three-week experimental period during which each subject consumed the control diet plus one of the four fiber supplements(20g/4ay) assigned on a random basis on the trust day. All meals were prepared and eaten in a metabolic feeding laboratory, with the exception of Saturday and Sunday meals that were packed for take-out. Fifty-seven healthy adult men, aged 18-65 years participated in the study. Dietary compliance index(CI) defined as the percent deviation of actual consumption from the prescribed food's and unconsumed prepared foods. The CI reflected the additional 'non-prescribed foods' and unconsumed 'prescribed foods'. A CI was calculated for all subjects. A CI of 5% or more was defined as poor compliance. Overall, dietary compliance was substantially improved for the entire group over the course of the study. Significant increase in compliance far energy and macronutrient intake occurred between the baseline and experimental periods. Within a non-obese group, dietary compliance fir energy improved from 5.5% to 3.3% by the end of the study(week 1vs week 5, respectively, p<0.05). However, between non-obese and obese group, dietary compliance was not different. (Korean J Nutrition 31(5) : 957-964, 1998)