• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.53-61
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• 1994

Sungnam city, as a major satellite town, is located in the southeast of Seoul. Atmospheric conditions are so stable that air pollutants from various emissions are tend to resist change because Sungnam city is located in the Namhansansung valley. The industrial distribution of Sungnam city are composed of various manufactories such as foods, fibers, chemicals, machinery and electronics etc. The heavy metal concentrations and size distribution are the most important parameters influencing among the way in which respirable suspended particulate matter interact with the human respiratory system. Respirable suspended particulate matter was collected on glass fiber filters from April 1993 to February 1994 according to particle size using Anderson sampler during 10 days per month at Sungnam city. 6 heavy metals, Fe, Zn, Pb Mn, Cu and Cd, were analyzed by particle size with atomic absorption spectrophotometry . The results could be summarized as follows: 1. The annual arithmetic mean concentration of total suspended particulate was 116.3$\mu $g/m$^{3}$ m', seasonal variation was the highest in spring season(196.5$\mu $g/m$^{3}$) and the lowest in Summer Season(72.9$\mu $g/m$^{3}$). 2. The ratio of airborne particulate concentrations respirable to nonrepairable( Res/Non- Res) of annual arithmetic mean value was 5.8'1, seasonal variation was highest in the spring season(6.3 : 1) and lowest in the summer season(4.6 : 1). 3. During the spring season the shape of the size distribution was trimodal which showed peaks at 3 size groups, which were below of 0.43$\mu $m, 3.3∼4.7$\mu $m and above of 11.0$\mu $g/m$^{3}$ respectively. 4. Respirable suspended particulate matter concentrations of Zn, Pb Cu and Cd were the highest in below of 0.43$\mu $m as follows; 0.517$\mu $g/m$^{3}$, 0.411 $\mu $g/m$^{3}$, 0.062$\mu $g/m$^{3}$ and 0.0310$\mu $g/m$^{3}$ , respectively, Fe and Mn were the highest in the particle size range of 4.7 ∼ 7.0$\mu $m as follows; 2.504$\mu $g/m$^{3}$ and 0.095$\mu $g/m$^{3}$, respectively. 5. The Pt Cd, Zn, Cu, Fe and Mn concentrations of annual arithmetic mean value respirable to non- respirable( Res/Non- Res ) were 33.65, 19.27, 17.74, 10.54, 3.20 and 5.20, respectively.

• Journal of Korea Water Resources Association
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• v.34 no.4
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• pp.317-326
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• 2001

This study evaluates the errors involved in the area average rainfall amounts estimated by the arithmetic mean method, the Thiessen's weighting method, and the optimal weighting method from the estimation theory. This study was applied to the upstream part of Nam-Han river basin (upper part of Youngwal) and the following results could be obtained. First, in case the raingauges are located evenly over the basin, no obvious difference can be found in the area average rainfall amounts from the arithmetic mean method or from the Thiessen's weighting method. However, as these two methods cannot consider the spatial variability of rainfall, the estimation error could be higher when the spatial variability of rainfall is high. In our application the estimation error from the arithmetic mean method or the Thiessen's weighting method was also found to be higher than that from the method from the information theory, which considers the spatial variability of rainfall. Thus, we could conclude that for the rainy season of Korea or for the mountain area when and where the spatial variability of rainfall is high, a proper method of considering the spatial variability of rainfall should be used regardless of the basin size. The isohyetal method generally used for the large basins or the optimal weighting method from the estimation theory used in this study could be good alternatives for this case.

• Journal of the Chungcheong Mathematical Society
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• v.28 no.1
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• pp.1-12
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• 2015

We present a local convergence analysis for inexact Newton-like method in a Banach space under weaker Lipschitz condition. The convergence ball is enlarged and the estimates on the error distances are more precise under the same computational cost as in earlier studies such as [6, 7, 11, 18]. Some special cases are considered and applications for solving nonlinear systems using the Newton-arithmetic mean method are improved with the new convergence technique.

• Communications for Statistical Applications and Methods
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• v.7 no.2
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• pp.549-562
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• 2000

Default Bayes factors are computed to test the equality of one Poisson population mean and the equality of two independent Possion population means. As default priors are assumed Jeffreys priors, noninformative improper priors, and default Bayes factors such as three intrinsic Bayes factors of Berger and Pericchi(1996, 1998), the arithmetic, the median, and the geometric intrinsic Bayes factor, and the factional Bayes factor of O'Hagan(1995) are computed. The testing results by each default Bayes factor are compared with those by the classical method in the simulation study.

• Journal of the Korean Ceramic Society
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• v.31 no.10
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• pp.1141-1146
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• 1994

Cyclic fatigue experiment was carried out to predict the life time of alumina ceramics. Four kinds of model were suggested to obtain the adequate representative static stress corresponding to the cyclic stress applied to the alumina specimens. Arithmetic mean stress model gives 21.81 of the crack growth exponent, integrated stress model gives 22.15, maximum stress model gives 24.57, and equivalent static stress model gives 24.43. It is considered that the equivalent static stress model is the most reasonable and gives the best adequate crack growth exponents value.

• Journal for History of Mathematics
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• v.12 no.1
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• pp.1-12
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• 1999

The first part of this thesis discusses the types and the properties of errors, one of which makes up systematic errors of measurements, removable by detecting their causes, the other errors of accidental causes which can not be removed. The final part of this thesis deals with the historical background of the Gaussian distribution by Hershel, Hagen, Laplace and Gauss from the late 18th century to the early 19th century. It can be concluded that the accidental idea and the treatment of accidental error distribution by Gauss Is the best one based on the assumption that the most probable value of true value is the arithmetic mean of data, obtained by repeated measurements of a given quantity.

• Journal of Families and Better Life
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• v.10 no.2
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• pp.61-74
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• 1992

The purpose of this study is to identify a typology of urban marred women's leisure activities based on participation data. The survey of this research was conducted by means of interview with 606 married women in Seoul. The instruments of the survey sere questionnaire including a leisure participation scale. Data were analysed by means of the statistic of frequency. percentage, arithmetic mean, standard deviation and factor analysis ,using the SPSS-X and SPSS/PC+ programs. The result was that the leisure activities of urban married women could be grouped into 5 factors; self-developing , family-oriented. religious-social, sociable, and time-spending activities For further researches, we suggested several proposals.

• Journal of Preventive Medicine and Public Health
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• v.20 no.2 s.22
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• pp.261-269
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• 1987

In order to investigate working conditions of underground coal mines, this work was undertaken to evaluate the respirable dust and the concentration of quartz in Taeback and Kangneung areas. The concentration of quartz was determined by Fourier Transform Infrared Spectrophotometry. The results were as follows; 1) The concentration of respirable dust of drilling and coal face in Taeback and Kangneung areas were as followed; Arithmetic $Mean{\pm}S.D.(mg/m^3)$ Taeback Drilling: $2.00{\pm}1.56$ Taeback Coal Face: $3.74{\pm}3.14$ Kangneung Drilling: $4.55{\pm}4.51$ Kangneung Coal Face: $5.77{\pm}4.53$ Geometric $Mean{\pm}S.D.(mg/m^3)$ Taeback Drilling: $1.34{\pm}2.81$ Taeback Coal Face : $2.55{\pm}2.61$ Kangneung Drilling : $2.44{\pm}3.63$ Kangneung Coal Face: $4.24{\pm}2.37$ 2) Distribution of respirable dust was well fitted to the log-normal distribution and geometric mean value was $log^{-1}\;0.37{\pm}log^{-1}\;0.47(2.34{\pm}2.95)mg/m^3$. 3) The difference of respirable dust concentrations in Taeback and Kangneung areas was not significant statistically (p>0.05). 4) The concentration of quartz of drilling and coal face in Taeback and Kangneung areas were as followed; Arithmetic $Mean{\pm}S.D.(%)$ Taeback Drilling: $6.18{\pm}5.52$ Taeback Coal Face: $1.89{\pm}1.54$ Kangneung Drilling: $3.54{\pm}2.12$ Kangneung Coal Face: $2.05{\pm}3.37$ Geometric $Mean{\pm}S.D.(%)$ Taeback Drilling: $4.24{\pm}2.59$ Coal Face: $1.39{\pm}2.22$ Kangneung Drilling : $2.55{\pm}3.08$ Kangneung Coal Face : $1.24{\pm}2.33$ 5) Distribution of quartz concentrations was well fitted to the log-normal distribution and geometric mean value was $log^{-1}\;0.33{\pm}log^{-1}\;0.45(2.14{\pm}2.82)%$. 6) The difference of quartz concentrations in Taeback and Kangneung areas was not significant (p>0.05), but significant at drilling sites and coal faces (p<0.05).

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.178-186
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• 2011

This study was conducted to investigate runoff characteristics of non-point pollutant sources in an agricultural area watershed in Boeun area, Chungbuk Province. The monitoring site represented 1.56 $km^2$, about 44.4% of which was covered with paddy fields. The monitoring was conducted for six events in a period of 5 month. Event Mean Concentration (EMC) and Site Mean Concentration (SMC) of suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (T-N) and total phosphorus (T-P) were calculated using the results of the water quality parameters. A comparison between arithmetic mean concentration and EMC revealed that nearly all EMCs were higher than the corresponding arithmetic mean concentrations. First-flushing effects were exhibited for SS, BOD, and T-P, with relatively high concentrations in early-stage storm events.

• Communications for Statistical Applications and Methods
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• v.19 no.3
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• pp.367-379
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• 2012

In baseball rankings, prediction has been a subject of interest for baseball fans. To predict these rankings, (based on 2011 data from Korea Professional Baseball records) the arithmetic mean method, the weighted average method, principal component analysis, and principal component regression analysis is presented. By standardizing the arithmetic average, the correlation coefficient using the weighted average method, using principal components analysis to predict rankings, the final model was selected as a principal component regression model. By practicing regression analysis with a reduced variable by principal component analysis, we propose a rank predictability model of a pitcher part, a batter part and a pitcher batter part. We can estimate a 2011 rank of pro-baseball by a predicted regression model. By principal component regression analysis, the pitcher part, the other part, the pitcher and the batter part of the ranking prediction model is proposed. The regression model predicts the rankings for 2012.