• Atmosphere
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• v.20 no.3
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• pp.367-377
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• 2010

Variation of tracer distribution during the vortex-breakup period in the Antarctic region was observed by the data from the Improved Limb Atmospheric Spectrometer (ILAS) and ILAS-II. All four trace species including methane, nitrous oxide, ozone, and water vapor show similar patterns of vertical gradient in spite of different structures of zonal mean mixing ratio. Timings of vortex breakup on each level are estimated by two different methods, and they are compared with zonal standard deviations following the latitude circle of each trace species. Although the tracers have different chemical life times and sink/source, the zonal standard deviation patterns show remarkable similarities. The zonal standard deviation shown here to measure the zonal asymmetry of tracer distribution is believed to diagnose the timing of the Antarctic polar-vortex breakup reasonably well.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1662-1669
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• 2006

Since randomness and uncertainties of design parameters are inherent, the robust design has gained an ever increasing importance in mechanical engineering. The robustness is assessed by the measure of performance variability around mean value, which is called as standard deviation. Hence, constraints in robust optimization problem can be approached as probability constraints in reliability based optimization. Then, the FOSM (first order second moment) method or the AFOSM (advanced first order second moment) method can be used to calculate the mean values and the standard deviations of functions describing constraints and object. Among two methods, AFOSM method has some advantage over FOSM method in evaluation of probability. Nevertheless, it is difficult to obtain the mean value and the standard deviation of objective function using AFOSM method, because it requires that the mean value of function is always positive. This paper presented a special technique to overcome this weakness of AFOSM method. The mean value and the standard deviation of objective function by the proposed method are reliable as shown in examples compared with results by FOSM method.

• Communications for Statistical Applications and Methods
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• v.4 no.2
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• pp.507-514
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• 1997

Three kinds of unbiased estimators of standard deviation in a truncated arcsine distribution based on the quasi-range, the jackknife quasi-range, and the angle jackknife range are proposed and numerically compared each other in a sense of MSE.

• Journal of Intelligence and Information Systems
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• v.22 no.2
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• pp.115-125
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• 2016

The Bollinger Band indicating the current price position in the recent price action range is obtained by adding/substracting the simple standard deviation (SSD) to/from the simple moving average (SMA). In this paper, we first compare the characteristics of the SMA and the exponential moving average (EMA) in the operator's point of view. A basic equation is obtained between the interval length N of the SMA operator and the weighting factor ${\rho}$ of the EMA operator, that makes the centers of the 1st order momentums of each operator impulse respoinse identical. For equivalent N and ${\rho}$, frequency response examples are obtained and compared by using the discrete time Fourier transform. Based on observation that the SMA operator reacts more excessively than the EMA operator, we propose a novel exponential standard deviation (ESD) band centered at the EMA and derive an auto recursive formula for the proposed ESD band. Practical examples for the ESD band show that it has a smoother bound on the price action range than the Bollinger Band. Comparisons are also made for the gap corrected chart to show the advantageous feature of the ESD band even in the case of gap occurrence. Trading techniques developed for the Bollinger Band can be straight forwardly applied to those for the ESD band.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.1-8
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• 2015

This paper presents a Electrocardiogram(ECG) identification method using adaptive weight based on Least Mean Square Error(LMSE) optimization. With a preprocessing for noise suppression, we extracts the average ECG signal and its standard deviation at every time instant. Then the extracted information is stored in database. ECG identification is achieved by matching an input ECG signal with the information in database. In computing the matching scores, the standard deviation is used. The scores are computed by applying adaptive weights to the values of the input signal over all time instants. The adaptive weight consists of two terms. The first term is the inverse of the standard deviation of an input signal. The second term is the proportional one to the standard deviation between user SAECGs stored in the DB. Experimental results show up to 100% recognition rate for 32 registered people.

• Journal of the Korean Society of Visualization
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• v.16 no.2
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• pp.23-30
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• 2018

The present study compares flow fields reconstructed by data assimilation method with different combinations of parameters. As a data assimilation method, Vortex-in-Cell-sharp (VIC#), which supplements additional constraints and multigrid approximation to Vortex-in-Cell-plus (VIC+), is used to reconstruct flow fields from scattered particle tracks. Two parameters, standard deviation of Gaussian radial basis function (RBF) and grid spacing, are mainly tested using artificial data sets which contain few particle tracks. Consequent flow fields are analyzed in terms of flow structure sizes. It is demonstrated that sizes of the flow structures are proportional to an actual scale of the standard deviation of RBF. It implies that a combination of larger grid spacing and smaller standard deviation which preserves the actual standard deviation is able to save computational resources in case of a low track density. In addition, a simple comparison using an experimental data filled with dense particle tracks is conducted.

• Journal of Advanced Navigation Technology
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• v.16 no.6
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• pp.960-967
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• 2012

Wireless sensor network is used at the environment to obtain nearby information and since such information is transferred through wireless link, it causes unnecessary re-sending and disadvantage of big energy consumption at node. Because of this to select reliable, energy effective link, method of estimating quality on wireless link using RSSI(received signal strength indication), LQI(link quality indication), etc is needed on wireless link. To set up path extending survival time by reducing energy consumption of nodes at the wireless sensor network, the thesis selects with small standard deviation of LQI after obtaining LQI within each path. Additionally, LQI standard deviation routing algorithm is compared based on LQI algorithm such as minimum-LQI, hop-LQI weight and RF output -7dBm. According to the outcome, the algorithm suggested has superior characters such as the number of node, retransmission rate and network life span respectively compared to existing algorithm. Therefore, energy consumption can be efficiently reduced in case that LQI standard deviation routing scheme suggested by this paper is adapted to wireless sensor network.

• Journal of Korean Public Health Nursing
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• v.9 no.1
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• pp.44-58
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• 1995

This study was to investigated the relationship between health locus of control and health promoting behavior of College students. For this study, questionnaires were given to 300 students in the H University of Seoul and collected during the period from Nomber 17 to November 24, 1994. Health locus of control and health promoting behavior were measured by using the MHLC scale and a modified HPLP scale. Healthiness of life style is parameterized by self actualization, health responsibility, exercise, nutrition, stress management, and internal support. The data were analyzed using the statistics package SAS, yielding frequency, percentage, mean, standard deviation, t-test, ANOVA, Pearson's Correlation. The result of this analysis are as follows: 1. Among the components of health locus of control, internal health locus of control showed the highestscore (mean: 3. 12, standard deviation: 0.46). Powerful others health locus of control followed next with the mean of 2. 30 and the standard deviation of 0.44. Chance health locus of control showed the mean of 2.29, and the standard deviation of 0.43 2. The HPLP mean score and the standard deviation of practice of health promoting behavior were 2.51 and 0.31 respectively. 3. HPLP correlated positively with internal health locus of control (r= 0.20, p<.01) and powerful others locus of control (r= 0.21. p<.001). However, HPLP inversely correlated with chance locus of control (r=-0.13, p<.05) 4. The demographic variables representing sex (t= 2.26, p<.05), health status (F = 5.52, p<.01) showed connections to health promoting behavior. Therefore, nurses should consider health locus of control when they take care of College students to improve such health promoting behavior as self actualization, exercise, internal support, stress management, and health responsibility. Further research is required to discover factors influencing health promoting behavior of College students.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.567-570
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• 2008

The present study investigated the applicability of the minium fludization velocity measuring method using linear regression analysis between the standard deviation of pressure fluctuation and gas velocity in multi-particle sand on a fluidized bed 0.109 in inner diameter. We measured minium fludization velocity according to the standard deviation of particle distribution in Gaussian distribution. The measured value compared with other researchers' equations. The minium fludization velocity derived from the linear regression analysis of the standard deviation of pressure fluctuation and pressure drop inside the bed. We also found that the minium fludization velocity of a multi-particle system using the standard deviation of pressure fluctuation must be measured at freely bubbling region.

• The Korean Nurse
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• v.36 no.3
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• pp.70-80
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• 1997

This study of elderly in-patient subjects' expected level of care given by family members and nurses is intended to provide foundational information for use by nurses is attending to elderly patients. The objects of the study were elderly in-patients over the age of 65 hospitalized at two General hospitals in Chonju: 102 subjects filled out the 60 question survey between December 16 and 24. 1996. The analysis process was conducted using SPSS producing percentage. mean and standard deviation. maximum and minimum values. t-test, ANOVA. and so on. The results are as follows: 1. From the general results of the survey. one can observe that statistically significant differences appeared in various levels of education of the subjects: no education(2.98). primary school completed(2.91). middle school or higher completed(2.77). As shown. the lower level of education correlates with higher care-giving expectation. 2. On a scale of 1(minimum) to 4(maximum). the mean levels of care expected by elderly inpatients from their families is 2.93. with a standard deviation of 0.28. The level of psychological care expected(mean 3.02. standard deviation 0.31) is higher than the level of care expected(mean 2.83. standard deviation 0.34). 3. The level of care expected among those of different levels of dependency for daily living (differentiated as dependent. partially dependent. independent) was highest among the partially dependent(mean 2.98. standard deviation 0.17). but the results were not statistically significant. 4. Elderly in-patients with high levels of emotive interaction with their families expected relatively high levels of physical care. while the highest levels of socio-psychological care were expected from those who reported normal levels of emotive interaction with their families. However. We can see that low levels of care are expected from those reporting low levels of emotive interaction with their families. Overall. the differences in the level of care expected between those reporting different levels of emotive interaction with their families was not shown to be statistically significant.