• Title/Summary/Keyword: Effective

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Sensitivity analysis of effective imperviousness estimation for small urban watersheds (도시 소유역 유효불투수율의 민감도 분석)

  • Kim, Dae Geun;Ko, Young Chan
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.2
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    • pp.181-187
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    • 2009
  • In this study, a runoff hydrograph and runoff volume were calculated by using the kinetic wave theory for small urban watersheds based on the concept of low impact development(LID), and the effective imperviousness was estimated based on these calculations. The degree of sensitivity of the effective imperviousness of small watersheds to the impervious to pervious area ratio, infiltration capability, watershed slope, roughness coefficient and surface storage depth was then analyzed. From this analysis, the following conclusions were obtained: The effective imperviousness and paved area reduction factor decreased as the infiltration capability of pervious area increased. As the slope of watersheds becomes sharper, the effective imperviousness and the paved area reduction factor display an increasing trend. As the roughness coefficient of impervious areas increases, the effective imperviousness and the paved area reduction factor tend to increase. As the storage depth increases, the effective imperviousness and the paved area reduction factor show an upward trend, but the increase is minimal. Under the conditions of this study, it was found that the effective imperviousness is most sensitive to watershed slope, followed by infiltration capability and roughness coefficient, which affect the sensitivity of the effective imperviousness at a similar level, and the storage depth was found to have little influence on the effective imperviousness.

Comparative Analysis of Estimation Methods for Basin Averaged Effective Rainfall Using NRCS-CN Method (NRCS-CN 방법을 이용한 유역평균 유효우량 산정기법의 비교·분석)

  • Moon, Geon-Woo;Yoo, Ji-Young;Ahn, Jae-Hyun;Kim, Tae-Woong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.2
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    • pp.493-503
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    • 2014
  • The NRCS-CN method is generally applied for estimating effective rainfalls in practice, in which the basin-averaged CN is normally used. In order to develop a more appropriate method for estimating effective rainfalls in a basin, this study compared estimated effective rainfalls from two distinct methods with the observed direct runoff. The first method is to estimate the basin-representative effective rainfall using the basin-averaged CN (hereafter, effective rainfall I), whereas the second method to estimate the basin-averaged effective rainfall through areal-averaging sub-area effective rainfalls corresponding to the soil type and landuse type (hereafter, effective rainfall II). The overall results indicated that the effective rainfall II was higher than the effective rainfall I and closer to the observed direct runoff. The study also performed error analyses to verify that the effective rainfall II can be applied in practice in a basin as more accurate estimate of basin-representative effective rainfall.

Analysis of Spectral Response Specification for the Infrared Channels of Meteorological Imager (기상 영상기의 적외선 채널 분광 응답 규격에 대한 분석)

  • Cho, Young-Min
    • Aerospace Engineering and Technology
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    • v.6 no.2
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    • pp.104-110
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    • 2007
  • Analyzed is the spectral response profile specification used for the infrared (IR) channels of the meteorological imagers of GOES series geostationary satellites. The variation characteristics of effective wavelength and effective input radiance due to the change of the spectral response function profile within the imager performance specification are analyzed in order to propose how to understand the spectral response specification. As an analysis approach, at first a center symmetrical spectral response function and 4 worst case spectral response functions are selected within the spectral response specification, and then effective wavelength and effective input radiance are calculated for each spectral response function. As a result, the maximum allowable ranges of effective wavelength and effective input radiance are provided per the spectral response specification.

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ON THE EFFECTIVE TEMPERATURES FOR EARLY TYPE STARS FROM INTEGRATED FLUXES

  • Woo, Jong-Ok
    • Journal of The Korean Astronomical Society
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    • v.17 no.2
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    • pp.104-114
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    • 1984
  • The effective temperatures, $T_{eff}$ (flux) of 52 early type stars are derived from de-reddened monochromatic and integrated fluxes obtained by absolute spectrophotometry, using the method of graphical analysis pioneered by Blackwell and Shallis (1977), similar to that of Underhill (1982) and Tobin (1983). We also estimated the effective temperatures, $T_{eff}$ (comp) of the same stars by comparing their de-reddened energy distributions with those of the LTE model atmospheres by Kurucz (1979). The effective temperatures derived from these two methods are found to be in good agreement, confirming that they are effective for the estimation of effective temperatures of early type stars.

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An Analytical Model for Predicting the Effective Thermal Conductivity of Woven Wire Wick Structure

  • Lee, Jin-Sung;Kim, Chul-Ju
    • International Journal of Air-Conditioning and Refrigeration
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    • v.10 no.2
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    • pp.72-78
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    • 2002
  • Woven wire wick is a very effective structure because of its easiness to insert inside of pipe for a miniature heat pipe. The present study was conducted to predict the porosity and the effective thermal conductivity of liquid-saturated woven wire wick. The porosity and the effective thermal conductivity of the evaporator region indicate different values from those of the condenser region due to the existence of non-flow region. The minimum value of the effective thermal conductivity indicates on condition of the $\theta$=$45^{Wcirc}$ and the values of the effective thermal conductivity increases symmetrically centering around the minimum value. The values of the effective thermal conductivity in the evaporator region at the angle of $45^{Wcirc}$ indicate about 60~80% higher than those in the condenser region for various combinations of copper, and stainless with water and ethanol.

Control Methods of Diseased of Japanese Flounder, Paralichthys olivaceus, used in Fish Farms, in Japan (현장(現場)에 있어서 양식(養殖)넙치의 질병대책(疾病對策))

  • Mizuno, Yoshitsugu
    • Journal of fish pathology
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    • v.6 no.2
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    • pp.219-231
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    • 1993
  • The author introduces the preventive and therapeutic methods of diseases in Japanese flounder which have been conducted by the Fish Disease Laboratory, the Mikamewan Fishery Cooperative Union, Ehime Prefecture, since 1982. Prevention 1. Addition of a sand substrate in the culture pond was effective to prevent ulcer disease. 2. Bathing in 0.5ppm of copper ion was effective to prevent some parasites. 3. Low stocking density of the fish reduced an incidence of edwardsiellosis or gliding bacterial disease. 4. Removal of the diseased fish prevented thd spread of lyphoeystis. 5. So-called $\pi$-water was effective to prevent the fry from some diseases. 6. Immersion of the juvenile in a sodium nifrusylate solution during transportation was effective to prevent gliding bacterial disease. Therapy 1. Sodium nifrustylate or oxytetracycline was effective to cure gliding bacterial disease. 2. Bathing in formalin(150ppm) or freshwater was effective to cure scuticociliatidosis. 3. Erythromycin was effective to cure $\beta$-hemolytic Streptococcus sp. infection. 4. Bathing in a hydrogen peroxide solution(1.5%) was effective to cure white spot disease.

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Evaluation of the Effective Rainfal on Upland by Lysimeter (라이시미터를 이용한 밭에서의 유효우량 산정)

  • 박승찬;정하우;최진용
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.87-92
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    • 1999
  • The evaluation of the effective rainfall is important in the desgin and operation of irrigation systems. But the difinition of the effective rainfall and the method for the estimating effective rainfall is various for each purpose . In this paper, the effective rainfall was defined as amount of rainfall which is remained in the effective soil depth that can be use to consumptive use of crop during growing season. The sol moisture was measured by Neutron prob for the effective rainfall estimation, and theexperiment was conducted for mulched and non-mulched condition of lysimeter during growing season. By the result of analysis and the former definition, the effective rainfall was estimated to be 37.2% for the mulched lysimeter and 40.7% for the non-mulched lysimeter.

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A Study on Conditions for Effective Home Management: Relations to Resourcefulness nd Communication (효과적 가정관리 조건에 관한연구: 자원 유용성 및 의사소통과의 관계를 중심으로)

  • 한경미
    • Journal of Families and Better Life
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    • v.17 no.2
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    • pp.105-120
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    • 1999
  • The purpose of this study was to examine dimensions related to effective managerial actions in association with effects of resourcefulness personal and managerial communications and condition s for effective home management on the basis of managerial process. Including elements of managerial process conditions for effective home management were divided into the four factors performance-condition dichotomy timing high level and middle range. In conclusion first the managerial process for effective management can be classified into the four conditions related to each other. That was termed as 'conditions for effective home management' Second the most influential variables on conditions for effective home management were personal and managerial communication. The four conditions for effective home management need to include communicaion. Third resuorcefulness was a crucial factor in relation to home management resources division. It is recommedned that resuorcefulness needs to de elop managerial actions of housewives.

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Validation of a Model for Estimating Individual External Dose Based on Ambient Dose Equivalent and Life Patterns

  • Sato, Rina;Yoshimura, Kazuya;Sanada, Yukihisa;Sato, Tetsuro
    • Journal of Radiation Protection and Research
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    • v.47 no.2
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    • pp.77-85
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    • 2022
  • Background: After the Fukushima Daiichi Nuclear Power Station (FDNPS) accident, a model was developed to estimate the external exposure doses for residents who were expected to return to their homes after evacuation orders were lifted. However, the model's accuracy and uncertainties in parameters used to estimate external doses have not been evaluated. Materials and Methods: The model estimates effective doses based on the integrated ambient dose equivalent (H*(10)) and life patterns, considering a dose reduction factor to estimate the indoor H*(10) and a conversion factor from H*(10) to the effective dose. Because personal dose equivalent (Hp(10)) has been reported to agree well with the effective dose after the FDNPS accident, this study validates the model's accuracy by comparing the estimated effective doses with Hp(10). The Hp(10) and life pattern data were collected for 36 adult participants who lived or worked near the FDNPS in 2019. Results and Discussion: The estimated effective doses correlated significantly with Hp(10); however, the estimated effective doses were lower than Hp(10) for indoor sites. A comparison with the measured indoor H*(10) showed that the estimated indoor H*(10) was not underestimated. However, the Hp(10) to H*(10) ratio indoors, which corresponds to the practical conversion factor from H*(10) to the effective dose, was significantly larger than the same ratio outdoors, meaning that the conversion factor of 0.6 is not appropriate for indoors due to the changes in irradiation geometry and gamma spectra. This could have led to a lower effective dose than Hp(10). Conclusion: The estimated effective doses correlated significantly with Hp(10), demonstrating the model's applicability for effective dose estimation. However, the lower value of the effective dose indoors could be because the conversion factor did not reflect the actual environment.

Comparison of the Equivalent Dose of the Lens Part and the Effective Dose of the Chest in the PET/CT Radiation Workers in the Nuclear Medicine Department (핵의학과 PET/CT실 방사선작업종사자의 수정체 부위의 등가선량과 흉부의 유효선량의 측정 비교)

  • Son, Sang-Joon;Park, Jeong-Kyu;Jung, Dong-Kyung;Park, Myeong-Hwan
    • Journal of radiological science and technology
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    • v.42 no.3
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    • pp.209-215
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    • 2019
  • Comparison of the effective dose of the chest and the equivalent dose of the lens site in the radiation workers working at four medical institutions with the PET / CT room located in one metropolitan city and province from April 1 to June 30, 2018 Respectively. Radioactive medicine were measured at the time of dispensing and at the time of injection. In this experiment, the average dispensing time per patient was 5.7 minutes and the average injection time was 3.1 minutes. The equivalent dose at the lens site was $0.78{\mu}Sv/h$ for 1 mCi, and the effective dose for chest was $0.18{\mu}Sv/h$ per 1 mCi. The equivalent dose at the lens site during injection was $0.88{\mu}Sv/h$ per mCi and the effective dose of chest was $0.20{\mu}Sv/h$ per mCi. The daily effective dose of the chest was $0.9{\pm}0.6{\mu}Sv$ and the equivalent dose of the lens site was $3.6{\pm}1.4{\mu}Sv$ during daily dosing for 20 days. The effective dose of the chest during the day was $0.6{\pm}0.5{\mu}Sv$ and the equivalent dose of the lens was $2.2{\pm}1.0{\mu}Sv$. At the time of dispensing, the equivalent dose of the lens was $0.187{\pm}0.035mSv$, the effective dose of the chest was $0.137{\pm}0.055mSv$, the equivalent dose of the lens was $0.247{\pm}0.057mSv$, and the effective dose of the monthly chest was $0.187{\pm}0.021mSv$. As a result of the corresponding sample test, the equivalent dose and the effective dose of the chest, the effective dose of the chest, the effective dose of the chest, the effective dose of the chest, The equivalent dose of the lens and the effective dose of the chest were statistically significant (p<0.05) with a significance of 0.000. However, there was no statistically significant difference (p>0.05) between the equivalent dose and the effective dose of the chest, the equivalent dose of the lens at the time of injection, and the effective dose of the chest at 0.138 and 0.230, respectively.