• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.218-218
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• 2016

차량용 강우 센서는 강우측정이 어려운 지역의 강수량 측정이 가능하고, 실시간으로 강우정보를 생성해 내기 때문에 차세대 강우측정기로써 전망이 기대된다. 차량용 강우 센서는 일반적인 강우관측기와 달리 물 입자가 커질수록 빛의 산란이 크게 일어나는 현상을 이용한다. 산란이 크게 일어나면 강우 센서에 입력되는 값이 줄고 이는 강수가 높다는 것을 의미한다. 강우가 발생하면 자동차 전면 유리창에 부착된 강우 센서가 감지하는 우적량을 강우량으로 환산하는 방법을 통해 강우량을 산정한다. 강우가 쌓이고 나서 나중에 그 값을 측정하는 것이 아니라 즉시 그 값을 계산하여 강우량을 산출해야하기 때문에 단계가 복잡하다. 수식이 복잡할수록 오차가 발생할 확률도 크고 처리 속도도 느려지기 때문에 W-S-R 관계식을 이용하여 복잡한 수식을 간단하게 정리할 필요가 있다. AWS 기상관측소와의 비교 분석을 위해 차량에 우량계를 장착하였으며 W-S-R 관계식을 통하여 상관관계 분석하여 회귀식을 도출 한다. W-S-R 관계식이라 함은 와이퍼의 속도관계(W), 강우센서(S), 실제 강우(R)을 의미한다. 여기서 와이퍼의 속도관계는 와이퍼의 한 번 이동 했을 시 실제 강우는 실내강우발생 장비를 제작하여 10~80mm의 강우를 발생시키고 그 값은 우량계로 관측한다. 본 연구에서는 물 입자의 산란과 차량용 강우 센서 간의 관계식 도출과 W-S-R 관계식을 이용하여 실제 강우 정보와의 상관관계를 위한 분석을 통한 회귀식 개발을 목표로 한다.

• Korean Journal of Remote Sensing
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• v.18 no.6
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• pp.319-326
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• 2002

Rainfall estimation was conducted based on TRMM-PR/VIES and GMS data. AWS rainfall data were used for various validation. General procedure is as follows; 1) Z-R relationship was made by the comparison of TRMM-PR and AWS data. 2) new algorithm was developed by the estimates from Z-R equation and TBB of VIRS. 3) rainfall was estimated through the substitution of GMS data for TBB of VIRS in the newly developed algorithm. Z-R relationship based on TRMM is $Z=303R^{0.72}$ with correlation coefficient 0.57. The newly developed algorithm is shown as correlation coefficient 0.67 and RMSE 17mm/hr. New algorithm shows the underestimating tendency in case of heavy rainfall event.

• Journal of the Korean earth science society
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• v.33 no.7
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• pp.596-607
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• 2012

The R-Z relationship is one of important error factors to determine the accuracy of radar rainfall estimation. In this study, we have explored the effect of the R-Z relationships derived from disdrometer data in estimating the radar rainfall. The heavy rain event that produced flooding in St-Remi, Quebec, Canada has been occurred. We have tried to investigate the severity of rain for this event using high temporal (2.5 min) and spatial resolution ($1^{\circ}$ by 250 m) radar data obtained from the McGill S-band radar. Radar data revealed that the heavy rain cells pass directly over St-Remi while the coarse raingauge network was not sufficient to detect this rain event. The maximum 30 min (1 h) accumulation reaches about 39 (42) mm in St-Remi. During the rain event, the two disdrometers (POSS; Precipitation Occurrence Sensor System) were available: One used for the reflectivity calibration by comparing disdrometer Z and radar Z and the other for deriving disdrometric R-Z relationships. The result shows the significant improvement with the disdrometric reflectivity-dependent R-Z relationships against the climatological R-Z relationship. The bias in radar rain estimation is reduced from +12% to -2% and the root-mean squared error from 16 to 10% for daily accumulation. Using the estimated radar rainfall rate with disdrometric R-Z relationships, the flood event was well captured with proper timing and amount.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.11-14
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• 1988

Field study was conducted to evaluate the relationship between daytime net radiation (Drn) and global solar radiation (Rs) and to develop the empirical equation predicting daytime net radiation above corn canopy from observations of Rs and Ta (mean daily air temperature). The relationship between Drn and Rs under the cloudless day was Drn = 0.6659Rs and that under the cloudy (> 35% of possible sunshine) Drn = 0.729Rs. Thus, Drn/Rs Ratio under cloudless day was found to be lower than that under the cloudy day. Rs and Ta were used in the radiation balance equation to estimate Drn and the empirical model could be expressed as $Drn=[0.9Rs-(352-227{\times}10^{-10}{\times}Ta^4)]$ [1.11Rs/Rso - 0.05].

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.178-178
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• 2018

차량용 강우센서는 강우에 따라 와이퍼의 동작 속도를 제어하기 위해 만들어졌다. 따라서 강수의 크고 적음을 대략적으로 판단하여 와이퍼의 속도단계를 결정하기 위한 장치이다. 차량용 강우 센서는 동작원리는 송수신되는 광신호에 기반한다. 일반적인 강우관측기와 달리 물 입자가 커질수록 빛의 산란이 크게 일어나는 현상을 이용한다. 산란이 크게 일어나면 강우 센서에 수광부의 광신호 값이 줄고 이는 강수가 높다는 것을 의미한다. 따라서 센서의 감지신호(Signal)와 실제강우(R)과의 관계를 이용하여 강우량으로 환산할 수 있는 R-S관계식을 개발하였다. 센서의 감지 신호(Signal)를 강우량으로 환산하기 위하여 실내 강우발생 실험 장치를 이용하여 일정 강우(R)를 증가시키고 그때 발생된 센서 감지량(S)의 관계를 수치적으로 분석하여 상관식을 만들었으며 실제 AWS, 자기우량계와 비교 분석하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.417-417
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• 2012

본 연구에서는 충청북도 보은군 수한면에 위치한 거현천의 사우교 지점에서 유량조사, 유사량 조사, 하상 퇴적물 조사를 실시하여 유량-총유사량 관계곡선식을 산정하였다. 총유사량 산정은 수정 아인쉬타인 방법을 적용하였으며, 2011년 홍수기에 4개의 호우사상에 대하여 16회 유량 및 유사량 조사를 실시하였다. 총유사량 산정의 실제적인 계산은 한국건설기술연구원에서 개발한 MODEIN 프로그램을 이용하였다. 사우교 지점 실측자료를 바탕으로 개발된 유량-부유사량 관계 곡선식은 $_s=2.4386Q^{1.9939}$이고, 결정계수 $R^2$=0.8307로 산정되었다. 유량-총유사량 관계곡선식은 $Q_s=3.1341Q^{2.0002}$이고, 결정계수 $R^2$=0.8599로 산정되었다. 본 연구를 통해 제시된 사우교지점의 유량-총유사량 관계식은 거현천의 기초자료로 활용될 것으로 사료된다.

• Journal of the Korean Chemical Society
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• v.29 no.3
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• pp.277-282
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• 1985

The effects of linear free energy relationship (LFER) on the imidoyl proton (H${\alpha}$)-substituent chemical shift (SCS) in case of varying para-substituted C-phenyl group in N-benzylideneaniline derivatives were studied. The H${\alpha}$-SCS values and LFER parameters such as ${\sigma}$,${\sigma}^+$, ${\sigma}_I$,${\sigma}_R, F and R were applied to the Hammett, Okamoto-Brown, and Taft, Swain-Lupton's dual substituents parameter (DSP) equations. The results were: (1) the blending coefficient values, ${\lambda}$ = 2.8∼3.2, it's means that the resonance effect (R) was larger than inductive effect (I) and field effect (F), and (2) the values of percent resonance and percent field effects were %R = 66.6 and %F = 33.4, respectively, yielding the ratio of resonance effect (R) to field effect (F) of 2 : 1.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.366-374
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• 2017

This study was conducted to explore the degree of female nursing student's dietary behavior, self esteem, dietary self-efficacy, life stress and the factors influencing dietary behavior of those surveyed. A total of 422 female nursing students in B, C city were surveyed. The data were collected between May 15 and 30 of 2016 and analyzed by a t-test, ANOVA, Pearson's correlation coefficients, and multiple regression analysis using SPSS WIN/21.0. The mean score of dietary behavior was $3.01{\pm}0.49$. In addition, there were significant differences in dietary behavior with respect to grade(F=4.823, p=0.008), residential type(F=6.067, p<.001), academic grade(F=3.907, p=0.021), health status(F=7.975, p<0.001), and degree of health concern(F=4.189, p=0.016). Moreover, there were negative correlations between dietary behavior and self esteem(r=-.238, p<0.001), and dietary self-efficacy(r=-0.438, p<0.001), while there was a positive correlation between dietary behavior and life stress(r=0.194, p<0.001). Regression analysis showed 26.7% of variance in female nursing student's dietary behavior can be explained by dietary self-efficacy, life stress, residental type, and degree of health concern. A follow-up survey investigating various factors influencing female nursing student's dietary behavior is needed and increased dietary behavior education and programs are required.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7321-7328
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• 2015

This study aimed to identify the difference and relation of eating and mental-psychological state according to the level of cigarette consumption in adolescents and to provide the basic data for the effective smoking cessation program. Data were obtained from the Ninth Korea Youth Risk Behavior Web-based Survey (2013 KYRBS). SPSS 18.0 was used to analyzed with descriptive statistics, ${\chi}^2$-test and Pearson's correlation coefficient. The results showed eating and mental-psychological state was a significant difference according to the level of cigarette consumption. Smoking amount were negative related to eating(r=-.154, p<.01) and there were positive related to mental-psychological state(r=.122, p<.01). There is negative correlation between eating and mental-psychological health(r=-.165,p<.01). Therefore, it is necessary to include eating and mental-psychological health to develop smoking cessation program for adolescents.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.941-951
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• 1994

The resilient behavior of subbase materials, locally used in Korea. were evaluated in this study by performing laboratory MR tests. The variations of the MR value according to LVDT's location in experiments and moisture conditions, respectively, were evaluated. And, in order to determine the relevant MR characteristics of the prototype materials, laboratory model tests containing smaller particles than those of the prototype were conducted. Based on above results, the relationship of the MR and the bulk stress (${\theta}$) was suggested. The case using internal LVDT. gave much larger $M_R$ value than that using external LVDT, since the external LVDT somewhat overestimates the resilient strain. The measured $M_R$ in damp conditions ($S_r$=40%) was larger than that in wet conditions ($S_r$=70%) by about 10%. The relationship between the $M_R$ and the void ratio was linear according to particle size effect. The relationship of the $M_R$ and the bulk stress (${\theta}$) on subbase materials in damp conditions to be used in Korea could be recommended as $M_R=3960{\cdot}{\theta}^{0.60}$ psi.