• Communications for Statistical Applications and Methods
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• v.18 no.3
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• pp.287-294
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• 2011

Peer assessment is an educational valuation system that involves studying with a colleague and granting value to the progress made by the colleague. Although this method has many merits, there is also a drawback pertaining to calculating the mean of the scores that were granted to the levels of contribution. However, this has been improved upon by a diversified study. However, the concept of the chi-square test and p-value used in the preceding study is not easy individuals engaged in the industrial engineering field or education when using peer assessment. This study uses simple statistics like standard deviation, in addition to, investigating the availability of a suggested method as well as examples of utility and application. This study can contribute to increase the convenience of users through the use of convenience analysis and with this method.

• Knowledge Management Research
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• v.19 no.2
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• pp.151-162
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• 2018

Response surface methodology (RSM) is one of popular tools to support a systematic improvement of quality of design in the product and process development stages. It consists of statistical modeling and optimization tools. RSM can be viewed as a knowledge management tool in that it systemizes knowledge about a manufacturing process through a big data analysis on products and processes. The conventional RSM aims to optimize the mean of a response, whereas dual-response surface optimization (DRSO), a special case of RSM, considers not only the mean of a response but also its variability or standard deviation for optimization. Recently, a posterior preference articulation approach receives attention in the DRSO literature. The posterior approach first seeks all (or most) of the nondominated solutions with no articulation of a decision maker (DM)'s preference. The DM then selects the best one from the set of nondominated solutions a posteriori. This method has a strength that the DM can understand the trade-off between the mean and standard deviation well by looking around the nondominated solutions. A posterior method has been proposed for DRSO. It employs an interval selection strategy for the selection step. This strategy has a limitation increasing inefficiency and complexity due to too many iterations when handling a great number (e.g., thousands ~ tens of thousands) of nondominated solutions. In this paper, a TOPSIS-based method is proposed to support a simple and efficient selection of the most preferred solution. The proposed method is illustrated through a typical DRSO problem and compared with the existing posterior method.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.5
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• pp.81-88
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• 2010

In this paper, we proposed an automatic music/non-music signal discrimination system from broadcasting audio signal as a preliminary study of building a sound source monitoring system in real broadcasting environment. By reflecting human speech articulation characteristics, we used three simple time-domain features such as energy standard deviation, log energy standard deviation and log energy mean. Based on the experimental threshold values of each feature, we developed a rule-based algorithm to classify music portion of the input audio signal. For the verification of the proposed algorithm, actual FM broadcasting signal was recorded for 24 hours and used as source input audio signal. From the experimental results, the proposed system can effectively recognize music section with the accuracy of 96% and non-music section with that of 87%, where the performance is good enough to be used as a pre-process module for the a sound source monitoring system.

• Analytical Science and Technology
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• v.32 no.2
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• pp.48-55
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• 2019

The simple and effective analytical method for the quality control of a novel scalp tonic formulation has been developed and optimized in terms of HPLC conditions and sample preparation method, meanwhile, the optimization of preparation condition was using response surface methodology (RSM) based on central composite design (CCD). Oleanolic acid was selected as marker compound because of its bioactivities for alopecia therapy. The developed analytical method and extraction condition were successfully qualified. Coefficient of determination ($r^2$) for the calibration was 0.9997 with a line passing through the origin point in the range of 0.1-100 mg/mL. The limit of detection (LOD) and the limit of quantitation (LOQ) were 17.5 ng/mL and 55.0 ng/mL, respectively. The intra-day and inter-day precision of the method were 0.5-1.4 % and 0.7-1.8 % in relative standard deviation, respectively, while those accuracy were 99.5-100.9 % and 100.0-102.2 %, respectively. The repeatability of oleanolic acid in samples ranged of 0.3-1.9 % based on peak area and 0.3-0.7 % for retention time. Recoveries from samples were 95.0-99.4 % with lower than 1.8 % in relative standard deviation. Overall, the developed analytical method will be used for quality control of this commercial scalp tonic products successfully.

• The Korean Journal of Applied Statistics
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• v.34 no.4
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• pp.589-597
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• 2021

In simple and multiple regression, there is a difference in the meaning of regression coefficients, and not only are the estimates of regression coefficients different, but they also have different signs. Understanding the relative contribution of explanatory variables in a regression model is an important part of regression analysis. In a standardized regression model, the regression coefficient can be interpreted as the change in the response variable with respect to the standard deviation when the explanatory variable increases by the standard deviation in a situation where the values of the explanatory variables other than the corresponding explanatory variable are fixed. However, the size of the standardized regression coefficient is not a proper measure of the relative importance of each explanatory variable. In this paper, the estimator of the regression coefficient in multiple regression is expressed as a function of the correlation coefficient and the coefficient of determination. Furthermore, it is considered in terms of the effect of an additional explanatory variable and additional increase in the coefficient of determination. We also explore the relationship between estimates of regression coefficients and correlation coefficients in various plots. These results are specifically applied when there are two explanatory variables.

• Journal of Food Hygiene and Safety
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• v.5 no.4
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• pp.213-217
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• 1990

A simple and practical method for the determination of caffeine in coffee, black tea and green tea was studied. The analysis of caffeine was performed by reverse phase high perfomance liquid chromatography using a ${\mu}-Bondapak$ C18 column at isocratic condition with methanol-acetic acid-water (20: 1: 79) on UV detector at 280 nm. The extraction and clean-up of caffeine in sample is based on combing a simple pretreatment with the use of a Sep-Pak Alumina A cartridge. The average recoveries of caffeine from several samples were 95.2 -101.3%, the relative standard deviation for the whole procedure was 0.10 ~ 0.62%, and the detection limit of caffeine in sample solution was about $0.1\;\mu\textrm{g}\;per\;ml$.

• Particle and aerosol research
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• v.10 no.1
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• pp.27-31
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• 2014

A simple bimodal model has been developed to analyze charged particle coagulation by modifying previously suggested bimdal model for evolution of particle generation and growth. In the present model, two monodisperse modes are used and 40 charge nodes are assigned to each mode to account both change of the particle size and charge distribution. In addition, we also implemented the effect of electrostatic dispersion loss in the present model. Based on the developed model, we analyzed coagulation of asymmetric bipolar charged particles by computing evolutions of particle number concentration, geometric mean diameter of particles, charge asymmetric ratio and geometric standard deviation of particle size distribution for various initial charge asymmetric ratios. The number concentration of asymmetric bipolar charged particles decreases faster than that of neutral particles but that does not give faster growth of particles since the electrostatic dispersion loss overwhelms particle growth by coagulation.

• Proceedings of the KIEE Conference
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• 2005.10a
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• pp.109-112
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• 2005

The main purpose of this study is to prepare an outline for developing of the module-type text-book system on the customize curriculum management and Contents Systems that achieve self-study systems to make the students adopt themselves into new study atmosphere and maximize the result of study on Osan college in Electric-Electronic field. Questionnaire posed to analyze the demand of teaching materials to the students, and professors and also to find characteristics of students in Osan college. The SPSSWIN/PC+ statistics package was used to assay the collected answers. And simple frequency with percentage, average, and standard deviation were calculated to check the entire trend and actual state of teaching. Therefore, the improvement of the existing teaching materials was demanded while the fundamental ability to study of general students is declining. Consequently, it is necessary to introduce new teaching materials which are simple, easy, and organized to offer the students study desire and interest.

• Journal of Information Processing Systems
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• v.16 no.6
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• pp.1324-1342
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• 2020

Various modified algorithms of rapidly-exploring random tree (RRT) have been previously proposed. However, compared to the RRT algorithm for collision avoidance with global and static obstacles, it is not easy to find a collision avoidance and local path re-planning algorithm for dynamic obstacles based on the RRT algorithm. In this study, we propose boundary-RRT*, a novel-algorithm that can be applied to aerial vehicles for collision avoidance and path re-planning in a three-dimensional environment. The algorithm not only bounds the configuration space, but it also includes an implicit bias for the bounded configuration space. Therefore, it can create a path with a natural curvature without defining a bias function. Furthermore, the exploring space is reduced to a half-torus by combining it with simple right-of-way rules. When defining the distance as a cost, the proposed algorithm through numerical analysis shows that the standard deviation (σ) approaches 0 as the number of samples per unit time increases and the length of epsilon ε (maximum length of an edge in the tree) decreases. This means that a stable waypoint list can be generated using the proposed algorithm. Therefore, by increasing real-time performance through simple calculation and the boundary of the configuration space, the algorithm proved to be suitable for collision avoidance of aerial vehicles and replanning of local paths.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.2
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• pp.95-100
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• 2008

A fast, simple, inexpensive, and reproducible sample preparation for extraction and analysis of HD in water was studied using single-drop microextraction(SDME) and GC-MS. Operation parameters, such as extraction solvent, extraction time were optimized. The optimized conditions were $1\{mu}L$ trichloroethylene and 10 min extraction time. In these conditions, about 42 times higher enrichment factor(EF) was obtained. The detection limit of HD was $1\{mu}g/L$, and the precision expressed as relative standard deviation was about 9.0%.