• 동굴
• /
• 제14권15호
• /
• pp.42-90
• /
• 1987

제주화산도의 암석학에 대한 암석기재 및 총화학 조성의 63종은 이문원에 의해 보고되고 있다. 총화학조성 데-타는 FORTRAN77의 프로그램에 의해 해석을 하였다. 해석에는 우선 최소자집법에 의해 환산식과 산분도를 검토했다. 다음에 통계적 데-타는 평균치, 최대치, 최소치, 범위, 표준편차, 분산, 표준오차 및 변동계수를 구했다. 표준편차의 큰 단위 물질은 SiO$_2$, MgO 및 FeO이고 작은 단위 물질은 MnO와 P$_2$O$_{5}$이다. 표준오차와 분산은 표준편차와 매우 유사한 조항이 있다. 그렇지만 변동계수는 표준편차와 다르다. 여기에서 큰 단위 변동계수는 $H_2O$$^{-}$ 및 $H_2O$$^{+}$이고, 작은 단위 변동계수는 $Al_2$O$_3$ 및 SiO$_2$ 이다. 상관계수의 계산은 정과 부의 상관성을 SiO$_2$, $Al_2$O$_3$ 및 TiO$_2$에 대해서 다른 조성과의 관계를 계산적으로 구할수 있다.

• Bioinformatics and Biosystems
• /
• 제1권2호
• /
• pp.115-122
• /
• 2006

A three-dimensional pharmacophore model was developed based on 24 currently available inhibitors, which were rationally selected from 472 compounds with diverse molecular structure and bioactivity, for generating pharmacophore of uPA (Urokinase Plasminogen Activator) inhibitors. The best hypothesis (Hypo1) comprised of five features, namely, one positive ionizable group, one hydrogen-bond acceptor group and three hydrophobic aromatic groups. The correlation coefficient, root mean square deviation and cost difference were 0.973, 0.695, and 94.291 respectively, suggesting that a highly predictive pharmacophore model was successfully obtained. The application of the model showed great success in predicting the activities of 251 known uPA inhibitors (test set) with a correlation coefficient of 0.837, and there was also none of the outcome hypotheses that had similar cost difference and RMS deviation (RMSD) with that of the initial hypothesis generated by Cat-Scramble validation test with 95% confidence level. Accordingly, our model should be reliable in identifying structurally diverse compounds with desired biological activity.

• 설비공학논문집
• /
• 제27권11호
• /
• pp.596-602
• /
• 2015

In this study, experiments using bioelectronic signals and questionnaire surveys were carried out in learning conditions when temperatures changed from low- and high-uncomfortable to comfortable. As a result, the stress factor Photoplethysmography (PPG) decreased, while the Root Mean Square of Standard Deviation (RMSSD) of PPG increased when the indoor temperature was changed from low- or high-uncomfortable to comfortable. Additionally, the absolute power of the ${\alpha}$-wave in the brain increased. According to the analysis of the association between the questionnaire and bioelectronic signals, the standard deviation of the stress factor as measured by pulse was closely related to the result of the thermal sensation questionnaire. In addition, it was found that the concentration on studying improved under comfortable temperatures when compared to uncomfortable temperatures.

• Nuclear Engineering and Technology
• /
• 제52권8호
• /
• pp.1771-1776
• /
• 2020

Adverse effects in the measured gamma spectrum caused by radioactive statistical fluctuations, gamma ray scattering, and electronic noise can be reduced by energy spectrum denoising. Wavelet threshold denoising can be used to perform multi-scale and multi-resolution analysis on noisy signals with small root mean square errors and high signal-to-noise ratios. However, in traditional wavelet threshold denoising methods, there are signal oscillations in hard threshold denoising and constant deviations in soft threshold denoising. An improved wavelet threshold calculation method and threshold processing function are proposed in this paper. The improved threshold calculation method takes into account the influence of the number of wavelet decomposition layers and reduces the deviation caused by the inaccuracy of the threshold. The improved threshold processing function can be continuously guided, which solves the discontinuity of the traditional hard threshold function, avoids the constant deviation caused by the traditional soft threshold method. The examples show that the proposed method can accurately denoise and preserves the characteristic signals well in the gamma energy spectrum.

• 터널과지하공간
• /
• 제12권4호
• /
• pp.268-276
• /
• 2002

In this study, a 3D coordinate measurement system equipped with a laser displacement meter for digitizing rock joint surface was established and the digitized data were used to calculate several roughness parameters. The parameters used in this study were micro avenge inclination $angle(i_{ave})$, average slope of joint $asperity(SL_{ ave})$, root mean square of $i-angle(i_{rms})$, standard deviation of height(SDH), standard deviation of $i-angle(SD_i)$, roughness profile $index(R_P)$, and fractal dimension(D). The relationships between the roughness parameters based on the digitzation of the surface profile were analyzed. Since the measured value varied according to the degree of reflection and the variation of colors at the measuring point, rock joint surface was painted in white to minimize the influence of the surface conditions. The comparison of the measured values and roughness parameters before and after painting revealed the better consequence from measurement on the painted surfaces. Also, effect of measuring interval was studied. As measured interval was increased, roughness parameters were exponentially decreased. The incremental sequence of degree of decrease was $SDH\; i_{ave},\; i_{rms},\; SD_i,\;and\; R_ p-1$. As a result of comparison of parameters from pin-type measurement system and laser type measurement system, all value of parameters were higher when laser-type measurement system was used, except SDH.

• Communications for Statistical Applications and Methods
• /
• 제18권3호
• /
• pp.287-294
• /
• 2011

동료평가는 일반적으로 교육 분야의 평가시스템에서 같이 학습을 하는 동료가 평가자가 되어 상대 학습자의 과정이나 결과물에 가치를 부여하는 것으로서, 많은 장점을 갖고 있음에도 불구하고 단순히 부여 받은 점수들의 평균을 계산하여 기여도를 산정한다는 단점 또한 갖고 있어 이를 개선하기 위한 다각적인 연구가 진행되어 오고 있다. 그런데 이들 선행연구에서 활용된 카이제곱 검정이나 유의확률 등의 개념은 동료평가를 활용하는 교육학이나 산업공학 분야에 종사하는 사람들에게는 쉬운 개념이 아니다. 이에 본 연구에서는 표준편차라는 간단한 통계를 이용하지만, 이들과 유사한 결과를 보이면서도 방법적인 측면에서 매우 간단한 동료평가의 가중치 부여방법을 제안하였다. 더불어 제안된 방법의 용이성과 효용성 및 활용 예에 대해서도 알아보았다. 본 연구는 간이분석법을 이용하여 이용자의 편리성을 증대시키는데 기여할 수 있다고 사료되는 바, 이러한 측면에 본 연구의 의의가 있다고 하겠다.

• 한국농림기상학회지
• /
• 제20권3호
• /
• pp.262-276
• /
• 2018

2016년부터 2017년까지 제주 감귤과수원 11개 지점에서 관측한 기상 및 이슬 자료를 이용하여 이슬지속시간 예측 모델을 평가하였다. 이슬지속시간 모델의 민감도와 예측 정확도 평가에는 4 가지 모델(Number of Hours of Relative Humidity, Classification And Regression Tree/Stepwise Linear Discriminant, Penman-Monteith, Deep-learning Neural Network)이 사용되었다. 모델의 민감도는 강우와 계절 변화에 따라 평가하였다. 전체 자료에서 강우일 자료를 제외하면 이슬지속시간 모델들은 평균 오차(평균제곱근오차 약 1.5 hours)가 적게 나타났다. 기계학습 모델은 겨울을 제외한 계절별 오차가 비슷한 크기(평균제곱근오차 약 3 hours)로 나타났다. 나머지 모델들은 여름에 오차(평균제곱근오차 약 9.6 hours)가 가장 크고 겨울에 가장 작은 것(평균제곱근오차 약 3.3 hours)으로 나타났다. 모델 예측 정확도 평가 방법은 통계적 오차 분석 방법과 평균 제곱 편차 회귀 분석 방법을 사용하였다. 통계오차를 통한 모델 성능은 DNN 모델이 가장 우수한 반면에 CART/SLD 모델은 예측 정확도가 가장 낮게 나타났다. 평균제곱 편차(MSD)는 모델의 선형성을 세 가지(제곱 바이어스(SB), 비균일성 기울기(NU), 상관관계 부족(LC)) 구성요소로 구분하여 분석하는 방법이다. 모델 성능이 우수할수록 SB와 LC는 감소하였고 NU는 증가하는 경향이 나타났다. MSD 분석 결과 DNN 모델이 가장 우수하였으며 다음으로 PM, NHRH, CART/SLD 순으로 나타났다. 본 연구에서 활용된 기계학습 모델은 기상 정보를 이용한 다른 농업정보 생산의 정확도 개선에 크게 기여할 것으로 판단된다.

• 한국지진공학회논문집
• /
• 제28권3호
• /
• pp.121-128
• /
• 2024

There are growing concerns that the recently implemented Earthquake Early Warning service is overestimating the rapidly provided earthquake magnitudes (M). As a result, the predicted damages unnecessarily activate earthquake protection systems for critical facilities and lifeline infrastructures that are far away. This study is conducted to improve the estimation accuracy of M by incorporating the observed S-wave seismograms in the near source region after removing the site effects of the seismograms in real time by filtering in the time domain. The ensemble of horizontal S-wave spectra from at least five seismograms without site effects is calculated and normalized to a hypocentric target distance (21.54 km) by using the distance attenuation model of Q(f)=348f^0.52 and a cross-over distance of 50 km. The natural logarithmic mean of the S-wave ensemble spectra is then fitted to Brune's source spectrum to obtain the best estimates for M and stress drop (SD) with the fitting weight of 1/standard deviation. The proposed methodology was tested on the 18 recent inland earthquakes in South Korea, and the condition of at least five records for the near-source region is sufficiently fulfilled at an epicentral distance of 30 km. The natural logarithmic standard deviation of the observed S-wave spectra of the ensemble was calculated to be 0.53 using records near the source for 1~10 Hz, compared to 0.42 using whole records. The result shows that the root-mean-square error of M and ln(SD) is approximately 0.17 and 0.6, respectively. This accuracy can provide a confidence interval of 0.4~2.3 of Peak Ground Acceleration values in the distant range.

• 대한임베디드공학회논문지
• /
• 제12권2호
• /
• pp.79-88
• /
• 2017

One of the important applications of activity sensing in the home is energy monitoring. Many previous methodologies for detecting and recognizing household appliances have been proposed. This paper presents an approach that uses an energy metering circuit (EMC) to classify and identify the various electrical devices in home based on root-mean-square (RMS) consumed current value. EMC gathers the RMS current values created by appliance state transition (e.g., on to off) and apparatus operating process. In this paper, an identification algorithm is proposed to detect a change in current levels using the standard deviation of current signals and their average values. In addition, characteristic of the appliance is extracted concerning four feature parameters concerning the number of current levels, the minimum level, the maximum level, and signal-to-noise ratio (SNR) of them. Experiment results validate the reliable performance of the proposed identification method for 11 representative appliances.

• 간호행정학회지
• /
• 제12권1호
• /
• pp.23-31
• /
• 2006

Purpose: The purpose of this study was to test the empowerment structural model based on Kanter's work empowerment theory. Method: A predictive, nonexperimental design was used in a sample of 279 nurses from 3 university affiliated hospitals. Data were collected with self-administered questionnaires and analyzed using mean, standard deviation, pearson correlation coefficient and path analysis. Results: The results showed that the overall fitness of the hypothethical model to the data was good(chi-square=.7751, df=4, p=.942, GFI=.999, AGFI=.996, RMSEA=.000). Both formal power and informal power directly influenced on nurses' perceived empowerment level and empowerment directly influenced on nurses' organizational commitment and indirectly influenced on nurses' intent to stay. Conclusion: The results imply that hospital and nurse managers should provide the empowering working condition for nurses to be stayed in hospitals.