• Journal of the Korean Solar Energy Society
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• v.31 no.5
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• pp.27-32
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• 2011

Most of domestic building generally don't have fixed shading devices considering of appearance and aesthetic issues. In this study is suggested that tilt window simultaneously has a role of shading and blocking solar radiation. The tilt window thermal performance is investigated by relation ship between inclination and heating cooling road. As comparing vertical window with $5^{\circ}$ and $7^{\circ}$ of tilt window respectively, the heating load is increased by 3.6% and cooling load is reduced by 8.1% on $5^{\circ}$ tilt window and the heating load is increased by 5.3% and cooling load is reduced by 11.5% on $5^{\circ}$ tilt window. Especially, the total load of alternative tilt window is showed the reduction rate 2.6% and3.6% compared of vertical window. Therefore, the tilt window is possible to role of shading of solar radiation and reduction of heating and cooling load.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.110-111
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• 2013

This research studies in the field of domestic fires are an issue in many scientific fire research as a research method to validate the domestic environment and ISO-9705 housing on the basis of experiments in virtual space by making a single fire compartment space for conducting experiments and Appearance of a fire occurring within each flammable Heat Release Rate analysis was carried out mainly. Placed within the space of one flammable HRR calculated as the sum of the number of single-room fire experiments conducted and the results compared with the value in comparing the conduct of fire locations and fire load within the building area of the future, the HRR value represents the change in domestic a consideration of the safety of the building is to propose matters.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.52.3-52.3
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• 2019

We investigate a relative contribution from short to long-term flaring rate to predicting M and X-class flare probabilities. In this study, we consider magnetic parameters summarizing distribution and non-potentiality by Solar Dynamics Observatory/Helioseimic and Magnetic Imager and flare list by Geostationary Operational Environmental Satellites. A short-term rate is the number of major flares that occurred in an given active region (AR) within one day before the prediction time. A mid-term rate is a mean flaring rate from the AR appearance day to one day before the prediction time. A long-term rate is a rate determined from a relationship between magnetic parameter values of ARs and their flaring rates from 2010 May to 2015 April. In our model, the predicted rate is given by the combination of weighted three rates satisfying that their sum of the weights is 1. We calculate Brier skill scores (BSSs) for investigating weights of three terms giving the best prediction performance using ARs from 2015 April to 2018 April. The BSS (0.22) of the model with only long-term is higher than that with only short-term or mid-term. When short or mid-term are considered additionally, the BSSs are improved. Our model has the best performance (BSS = 0.29) when all three terms are considered, and their relative contribution from short to long-term rate are 19%, 23%, and 58%, respectively. This model seems to be more effective when predicting active solar ARs having several major flares.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.202-208
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• 2001

Under the constant daylength of 13 hours and growth temperatures of 15$^{\circ}C$ to 27$^{\circ}C$, the final number of loaves (FNL) on the main culm was constant as 15 regardless of temperature in rice variety 'Kwanganbyeo'. Leaf appearance rate (LAR) increased with rising temperature and decreased with phenological development. Threshold temperature (T$_{o}$) was not constant across growth stages, but increased with phenological development. Effective accumulated temperature (EAT), which is calculated by the summation of values subtracting T0 from daily mean temperature, is closely related with number of leaves appeared (LA). LA was fitted to bilinear, quadratic, power and logistic function of EAT. Among the functions, logistic function had the best fitness of which coefficient of determination was $R^2$=0.995. Therefore, LAR prediction model was established by differentiating this function in terms of time: (equation omitted). where dL/dt is LAR, T$_1$ is daily mean temperature, L is the number of leaves appeared, and a, b, and c are constants that were estimated as 41.8, 1098.38, and -0.9273, respectively. When predictions of LA were made by LAR prediction model using data independent of model establishment, the observed and predicted LA showed good agreement of $R^2$$\geq$0.99.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.12 s.159
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• pp.1683-1689
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• 2006

Precedent researches on lyocell are mostly on lyocell structure, characteristics, physical properties by finishing and dyeability, and the like; there are little cases of researches on interlining for lyocell clothes production. To serve as a base information helpful to select fusible interlining and improve the efficiency of sewing process considering the characteristics of lyocell, this study performed t-est, F-test toward to the difference in the appearance-related properties and the mechanical properties of lyocell-interlining bonded fabric in accordance with the characteristics of fusible interlining and lyocell face fabric. This study reached following conclusions. Drapability and Crease recovery of lyocell-interlining bonded fabric are influenced by the structure of fusible interlining; stiffness of lyocell-interlining bonded fabric, by the structure of fusible interlining and the yam number of lyocell face fabric. WT is influenced by the mixture rate and yam number of lyocell face fabric. RT is influenced by the yam number of lyocell face fabric; G, 2HG, 2HG5, by the structure(woven and non-woven) of fusible interlining; B, HB, by the weight, structure(woven and non-woven) of fusible interlining, and yam number of lyocell face fabric; WC, by the weight, structure of fusible interlining; RC, by the structure of fusible interlining; thickness, by the weight of fusible interlining and the yarn number of lyocell face fabric; weight, by mixture rate and yam number of lyocell face fabric.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.2
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• pp.78-82
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• 2022

Phenology determines the timing of crop development, and the timing of phenological events is strongly influenced by the temperature during the growing season. In process-based model, leaf area is simulated dynamically by coupling of morphology and phenology module. Therefore, the prediction of leaf appearance rate and final leaf number affects the performance of whole crop model. The dataset for the model equation was collected from SPA R chambers with five different temperature treatments. Beta distribution function (proposed by Yan and Hunt (1999)) was used for describing the leaf appearance rate as a function of temperature. The optimum temperature and the critical value were estimated to be 26.0℃ and 35.3℃, respectively. For evaluation of the model, the accumulated number of onion leaves observed in a temperature gradient chamber was compared with model estimates. The model estimate is the result of accumulating the daily increase in the number of onion leaves obtained by inputting the daily mean temperature during the growing season into the temperature model. In this study, the coefficient of determination (R²) and RMSE value of the model were 0.95 and 0.89, respectively.

• The Journal of Korean Society for School & Community Health Education
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• v.9 no.1
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• pp.33-46
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• 2008

Objectives: The aim of this study was to investigate the correlation between the obesity rate in elementary school students in Daejeon and the relevant factors such as social-demographical factors, genetic factors, birth factors, diet factors and intelligence factors. Methods: For the research, 443 fourth grade students, 405 fifth grade students and 417 sixth grade students from six elementary schools in Daejeon Metropolitan City Participated in this study and classified into three groups: normal-weight group, mild obesity group, and moderate or severe obesity group. Results: The total obesity rate of the elementary school students in the school district of Daejeon Metropolitan City was 14.2%; the rate of mild obesity was 7.2%; the rate of moderate obesity was 5.5%; and the rate of severe obesity was 1.5%. The obesity rate of surveyed boys was 16.9%, and the obesity rate of girls was 11.1%. The significant factors for girls' obesity were fathers' EMI, mothers' EMI, living standards, constant demand of foods, preference for greasy foods, frequency of eating snacks, and daily walking hours. It was found that students' subjective mind and objective health index were related to obesity. In the case of obese students, they had more concern about their health and more stress from the dissatisfaction of their physical appearance than normal students. Conclusions: From the above evidences, it is apparent that the obesity of elementary school students has strong relations with eating habits rather than physical activities. It is to be hoped that obesity prevention programs such as effective meal guidance. parental guidance for watching TV, and intense physical activities will be included in the curriculums of health education for elementary school students.

• Journal of Korea Foundry Society
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• v.15 no.4
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• pp.388-396
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• 1995

This study has been conducted with the purpose of examining the fatigue crack growth characteristics of $Al_2O_3$ short fiber reinforced aluminum matrix composites made by squeeze casting process with different applied pressure and binder amount. Fatigue crack growth experiments have been performed under constant load amplitude method with a fixed load ratio. The rate of crack propagation was decreased with binder amount as well as applied pressure. Also fatigue crack growth path in matrix was changed from flat to rough mode with an increase of applied pressure. In the composites, fatigue crack was propagated to interface between matrix and reinforcement at 10MPa, but it was propagated to reinforcement at 20MPa. The major reason of thee result was considered that interfacial bonding force and microstructure of matrix were improved due to an increase of applied pressure. Localized ductile striation in the composites was observed at low growth rate region and such a phenominon was remarkable with an increase of applied pressure. At high growth rate region, the propensity of fracture appearance was changed from interfacial debonding to reinforcement fracture with an increase of applied pressure.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.5
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• pp.1984-2002
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• 2020

With the appearance of wireless spectrum crisis in traditional cellular network, device-to-device (D2D) communication has been regarded as a promising solution to ease heavy traffic burden by enabling precise content delivery among mobile users. However, due to the channel sharing, the interference between D2D and cellular users can affect the transmission rate and narrow the throughput in the network. In this paper, we firstly present a weighted interference minimization cluster formation model involving both social attribute and physical closeness. The weighted-interference, which is evaluated under the susceptible-infected(SI) model, is utilized to gather user in social and physical proximity. Then, we address the cluster formation problem via spectrum clustering with iterative operation. Finally, we propose the stable matching theory algorithm in order to maximize rate oriented to accomplish the one-to-one resource allocation. Numerical results show that our proposed scheme acquires quite well clustering effect and increases the accumulative transmission rate compared with the other two advanced schemes.

• ALGAE
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• v.25 no.1
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• pp.17-26
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• 2010

The effects of salinity on various ecophysiological parameters of Ulva pertusa such as growth, nutrient uptake, photosynthetic performance and internal nutrient composition were tested. U. pertusa was collected from an eelgrass bed in a semi-protected embayment on the southwest coast of Korea. Under salinity regimes from 5 to 40 psu, the specific growth rates $(\mu)$ of U. pertusa ranged from 0.019 to $0.032\;d^{-1}$. Maximum growth rate was observed at 20 psu, and minimum at 40 psu. This species showed various uptake rates for nitrate and phosphate. Nutrient uptake was noticeably higher at intermediate salinity levels, and lower at both extremes. Salinity significantly influenced chlorophyll-$\alpha$ content and effective quantum yield. Tissue nitrogen content ranged from 1.5 to 2.9% N (dry weight), whereas tissue phosphorus ranged from 0.1 to 0.14% P (dry weight). The N : P ratio in the tissue of U. pertusa was considerably higher, ranging from 30 to 50. Increased growth at lower salinity suggests that the initial growth rate of U. pertusa is greater during the rainy season (i.e., late spring and early summer) than any other season during the year. The appearance of an Ulva bloom in eelgrass beds may be triggered by salinity more than by other environmental factors such as light and temperature.