• Journal of the Korean Society of Safety
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• v.28 no.5
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• pp.61-65
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• 2013

Occupational stresses of steel manufacturing workers have been investigated using an organized questionnaire composed of 40 items. Three hypothesizes were developed based on the literature review of related researches. Empirical data surveyed from ones working in steel manufacturing jobs were collected and the in-depth statistical analyses using Statistical Package for the Social Sciences(SPSS) software were performed. These statistical results indicate that the existence of occupational stress may cause to take place industrial accidents. Consequentially, the prevention of occupational stress helps to promote the will to work, following by increasing job satisfaction in working circumstance of steel manufacturing.

• Computers and Concrete
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• v.18 no.1
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• pp.113-137
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• 2016

Extensive experimental studies on remarkable mechanical properties Polypropylene Fibre Reinforced Self-compacting Concrete (PFRSCC) have been executed, including different fibre volume fractions of Polypropylene fibers (0.25%, 0.5%, 0.75%, and 1%) and different water to cement ratios (0.21, 0.34, 0.38, and 0.41). The experimental program was carried out by using two hundred and sixteen specimens to obtain the impact resistance and mechanical properties of PFRSCC materials, considering compressive strength, splitting tensile strength, and flexural strength. Statistical and analytical studies have been mainly focused on experimental data to correlate of mechanical properties of PFRSCC materials. Statistical results revealed that compressive, splitting tensile, and flexural strengths as well as impact resistance follow the normal distribution. Moreover, to correlate mechanical properties based on acquired test results, linear and nonlinear equations were developed among mechanical properties and impact resistance of PFRSCC materials.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.625-632
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• 2001

Principal component analysis(PCA) is a multivariate technique falling under the general title of factor analysis. The purpose of PCA is to Identify the dependence structure behind a multivariate stochastic observation In order to obtain a compact description of it. In engineering field PCA is utilized mainly (or data compression and restoration. In this paper we propose a new robust Hebbian algorithm for robust PCA. This algorithm is based on a hyperbolic tangent function due to Hampel ef al.(1989) which is known to be robust in Statistics. We do two experiments to investigate the performance of the new robust Hebbian learning algorithm for robust PCA.

• The Korean Journal of Applied Statistics
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• v.6 no.1
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• pp.1-11
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• 1993

Statistical graphics have been important new tools for data analysis and many statistical softwares are exploiting graphical methods. Among these softwares available in personal computer at low cost, we intriduce S-PLUS(version 2.0). S-PLUS is an interactive graphical data analysis system and object-oriented programming language. SAS/GRAPH is another popular graphical system for displaying data in the form of color plots, charts, maps, and slides on screen and hardcopy devices. S-PLUS is compared to SAS/GRAPH(version 6.04) in viewpoints of statistical graphics.

• Journal of electromagnetic engineering and science
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• v.13 no.3
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• pp.192-194
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• 2013

This paper proposes a validation model using a reverberation chamber for verification of the effectiveness and accuracy of the statistical power balance (PWB) method. The PWB method treats electromagnetic (EM) field distributions in certain environments as a representative value of an "ensemble" average, so a reverberation chamber is utilized as a testing apparatus to experimentally simulate the sets of measurement field "ensemble" inside a complex environment. Measurements are performed with various test conditions for environmental loss using flat absorbers, and front and side doors of the chamber. Comparison between the PWB analysis and the measurement results shows good agreement, indicating the usefulness of this statistical analysis method for stating the electromagnetic field inside the EM zone as a representative value to general structures.

• Publications of The Korean Astronomical Society
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• v.19 no.1
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• pp.55-63
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• 2004

Observation environment of the Bohyunsan Optical Astronomy Observatory(BOAO) has been examined using various statistical data including real observation times versus allocated times and seeing statistics. The data have been collected from the observation logs of the 1.8m telescope in the period 1998 - 2004. New criteria have been set up to calculate a more realistic observation efficiency of the observatory. The new statistical analysis based on the new criteria gives the overall observation efficiency of BOAO as $38.6\%$, that is equivalent to 115.8 observable nights out of 300 allocatable nights. The seeing statistics shows that the mean seeing measured at the focal images is 2".3. The present study of the observation environment of BOAO suggests that differential photometry and spectroscopy should be preferred modes of observation to maximize the productivity of BOAO.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.35.3-35.3
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• 2018

Incorporating the fully quantum mechanical computation of scattering cross-section and statistical moment analysis of absorption profiles, we investigate the Lyman line asymmetry of extremely high column density systems. Recent high redshift observations detected strong damped Lyman alpha systems (DLAs) whose column density is larger than N_HI ~ [10]^21.3 cm^(-2). Absorption profiles of these DLAs are characterized by the broad and asymmetric damping wing. For accurate description of radiation damping, the second-order time-dependent perturbation theory is adopted. To quantitatively address line asymmetry, we define a distribution function for each Lyman line, and compute statistical moments (mean, standard deviation, skewness and kurtosis) regarding column densities N_HI > [10]^18 cm^(-2). In this work, we present statistical properties of the intrinsic line profiles, and compare them with the Lorentzian cases.

• Korean Journal of Oriental Medicine
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• v.13 no.3
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• pp.45-51
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• 2007

This Study is to propose the method about statistical factor from the old oriental medical record in Korea. This Study reviews the statistical analysis recently published in the old oriental medical books which are in the Research Report by the Korea Institute of Oriental Medicine at 2007. The results reveal a disease factors, prescription factors.medicines factors, population factors and historical factors by the statistics. The results show that the old oriental medical record for a information system need the interpreting with a information analysts, a statistics analysts and an oriental medical doctors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.45-51
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• 1970

By means of past data, taken from the annual catches of anchovy landings in Korea, from the year 1926 to 1967, as reported in the Annual Statistical deports of Fisheries, the future annual catches from the year 1968 to 1973 were predicted by statistical extrapolation. The trend C(t) in the 42 year period above was interpreted by the least square method. Also, the ratio of the actual annual catches Ct to this trend C(t) was regarded as a stationary variate and the serial correlation coefficients $r_k$ were calculated. The type of statistical variate model was therefore determined by the correlogram. A periodical analysis, using Whittaker's method, was performed and a harmonic analysis was also performed. According to these calculations the stationary variate at was fixed and the annual catches following the year 1967 were predicted by extrapolation.

• Journal of the Korean Statistical Society
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• v.33 no.1
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• pp.1-24
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• 2004

This paper is concerned with statistical methods for multivariate data when the number p of variables is large compared to the sample size n. Such data appear typically in analysis of DNA microarrays, curve data, financial data, etc. However, there is little statistical theory for high dimensional data. On the other hand, there are some asymptotic results under the assumption that both and p tend to $\infty$, in some ratio p/n ${\rightarrow}$c. The results suggest that the new asymptotic results are more useful and insightful than the classical large sample asymptotics. The main purpose of this paper is to review some asymptotic results for high dimensional statistics as well as classical statistics under a high dimensional asymptotic framework.