• The Transactions of the Korea Information Processing Society
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• v.2 no.6
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• pp.960-968
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• 1995

In this paper we present a reordering scheme that could lead to efficient vectorization of the preconditioners for the large sparse linear systems arising from partial differential equations on the CRAY-2, This reordering scheme is a line version of the conventional red/black ordering. This reordering scheme, coupled with a variant of ILU(Incomplete LU) preconditioning, can overcome the poor rate of convergence of the conventional red/black reordering, if relatively large number of fill-ins were used. We substantiate our claim by conducting various experiments on the CRAY-2 machine. Also, the computation of the Frobenius norm of the error matrices agree with our claim.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.8
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• pp.1952-1966
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• 1994

The body segment parameters of twelve young male Korean were measured to compare with the results of foreign cadaver studies. A human body was assumed to have fourteen body segments. The mass of each segment was measured with a water immersion test and the mass center of a segment was determined on the balance platform by changing postures. In the case of Korean, because of the difference in body proportion, the mass center of whole-body is located further from the distal end of head(Korean : 44.9% vs. Caucasian : 41.2%), and the mass center of each segment also located in different proportional locations. The existing regression equations, which can estimate segment mass based upon the anthropometric dimensions, estimates segment mass (the mass of shank) for Korean with 13% error. Therefore, it is not recommended to estimate the mass, and the moment of inertia of body segment of Korean based on the existing equations. However, the density information of body constituents was similar enough to apply it to Korean density. It was validated by the comparison between the results of the direct immersion method and 3-dimensional volume reconstruction of segment form the cross sectional images of CT-scan. The average body density measured form twelve subjects was $1.035{\;}kg/m^3$ and showed deceasing trendency.

• The korean journal of orthodontics
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• v.26 no.4
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• pp.414-420
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• 1996

Cephalometric measureements have disadvantage of representing cranio-facial structures in two dimension only and therefore they pose limitations in describing three-dimentional structures of cranio-facial region. More interests have been put on the correlation between the two planes. This study evaluated correlations between facial type score, which allows effects on malocclusion, growth change prediction and establishment of treatment method and prognosis, and measurements from submentovertex view. Cephalometric view and submentovertex view were taken of skeletal Class I adults with optimal profile and correlations between them have been observed. Following results were obtained: 1. To learn about factors that influence average condylar angulation, FACE, INT-CO-ANG, MN-CORPUS, CON-RATIO, GON-RATIO, MN-RATIO were used as variables and underwent multiple regression analysis. As a result, the following equation was obtained : CON-AVE=.l73(FACE)-.322(INT-CO-ANG)+36.34(GON-RATIO) +.420(MN-CORPUS) (($R^2=.85451$) 2. The following equation was obtained concerning facial type score. FACE= .050(CON-ANG)+.023(INT-CO-ANG)-.075(MN-CORPUS)($R^2=.31547$) 3. Among the submentovertex measurements, MN-CORPUS, CON-RATIO, GON-RATIO, MN-RATIO showed close correlations. (P<0.05) 4. Average condylar angualtions were $23.37^{\circ}$ on the right and $20.71^{\circ}$ on left. There was a difference between the two. FACE : facial type soore. CON-ANG: mean value of condylar angulation. CON-AVE: mean value of Rt. Lt condylar angulation. INT-CO-ANG : angle between Rt. Lt condylar axis. MN-CORPUS : angle formed between RT. Lt gonion & pogonion. CON-RATIO: lntercondylar distance/mandibular body length. GON-RATIO : intergonion distanoe/mandibular body length. MN-RATIO: lntermylohyoid distance/mandibular body length. MX-RATIO: intermaxillary tuberosity distance/ANS-PNS distance.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.113-119
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• 1984

Initial moisture content and weight of the rice bran and treatment time were identified as important variables for the inactivation of lipase and peroxidase present in rice bran. Multiple regression analysis was used to obtain a prediction equation to measure the effects of moisture content and weight of the sample and microwave treatment time on the residual lipase activity and loss in weight. It was found that the microwave treatment did not affect acid value and extractability of the rice bran oil.

• The Transactions of the Korea Information Processing Society
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• v.3 no.5
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• pp.1070-1081
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• 1996

In this research, a model was developed for estimating the queue length of vehicles, based on occupancy time of each vehicle collected by loop detectors which were setup at the upstream of urban street. The estimation model suggestes a method which minimizes architectural effects of the street, such as existence of pedestrian crossing, for future applications to the field. The estimation model suggested in this research was established based on real traffic data collected at up-stream detectors in Kangnam Subway station, Seoul, and the formula of the model is based on Multi-Polynomial equations. Consequence of the experiments showed that the model can adequately and in real-time mode measure length of the queue which were constructed at the 80 to 90 meters away from the upstream detectors. The estimation accuracy of the model was verified in statistical analysis conducted by regressing analysis and test results in real traffic situation.

• Journal of Global Scholars of Marketing Science
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• v.15 no.1
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• pp.1-20
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• 2005

The object of this study is to explore factors affecting customer satisfaction and customer loyalty of instant messenger service. We propose that service qualities (tangibility, assurance, responsiveness, empathy, reliability) affect customer satisfaction of instant messenger service, customer satisfactions do customer loyalty. As moderating factors of the relationship between customer satisfaction and customer loyalty, switching costs are suggested. To accomplish the object of this study data are collected from instant messenger user by survey research. We analyse the research model using structural equation model and moderated multiple regression. The result are as follows: (1) tangibility and responsiveness affect customer satisfaction. (2) customer satisfaction affects customer loyalty. (3) switching costs moderated the relationship between customer satisfaction and customer loyalty.

• Journal of Nutrition and Health
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• v.23 no.3
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• pp.170-178
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• 1990

The aim of the study was to investigate prevalence of obesity among housewives residing in apartments in Taegu city and any relationship of obesity with various factors. Hundred three housewives aged 30-49 years living in apartments (over 30 pyung) were interviewed for socio-economic status, food habit, food intake by a convenient questionnaire, and daily activity by the 24-hour recall. Their weight, height and triceps skinfold thickness were measured. The results were summarized as follows: 1) The percentages of subjects and their spouses with college and higher education were as much as 53.6% and 83.5%, respectively. The commonest family size was four members with two children. 2) The percentages of subjects classified as underweight, normal, overweight, and obesity according to relative body weight(RBW) were 4.9, 44.7, 24.3 and 26.2, respectively. Twenty four percent belonged to obese group according to body mass index(BMI$\geq$25). 3) Food habit score was 12.4 points in average and judged 'good'. The average of daily energy intake was 2247㎉ which corresponded to 112% of RDA and intakes of nutrients except iron exceeded RDA. The means of food habit score and energy intake were not significantly different among 4 groups. 4) Multiple regression analysis was tested to explain a relationship between fatness and various factors. The equation, BMI=25.216+(0.836$\times$family size)-(0.309$\times$education, years)-(0.00503$\times$household work time, minutes), indicates that fatness of housewives was related with family size(+), educational level(-) and household work time(-). These relationships were statistically significant(p<0.001) and R2 (coefficient of determination) was 0.237.

• Journal of agriculture & life science
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• v.46 no.5
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• pp.101-109
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• 2012

To investigate changes of components in salt-fermented anchovy sauce by long fermentation, various chemical properties were examined. The moisture, crude protein, crude lipid, and crude ash contents of the anchovy sauce by fermentation were 67.48~69.35%, 5.47~7.40%, 0.27~0.47% and 23.82~24.12%. The moisture and pH was decreased slightly, but the contents of crude protein, crude lipid, acidity and amino-N degree were increased gradually by long fermentation. And contents of crude ash, VBN and salinity showed almost no change. Total free amino acid contents of 1, 3, 6, 9 and 12 year fermented samples were 8,762.2 mg%, 9,484.6 mg%, 10,085.8 mg%, 10,650.7 mg% and 10,123.7 mg% respectively. Major free amino acid of samples were glutamic acid, leucine, lysine, alanine, valine, isoleucine in ordor. The samples were caused by their composition of the free amino acids rations, in which were umami, sweet and bitter taste in the extracts of anchovy during long fermentation. In Hunter values, fermented samples were generally lower in L, b values whereas higher in a, ${\Delta}E$ values. And absorbance at 453 nm was increased gradually by fermentation. Sensory evaluation result of samples, 6 years sample was the highest than the others in overall acceptance.

• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.193-198
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• 1997

The purpose of this study was to find out a suitable resin to remove $NO_3-N$ from groundwater. Four different commercial resins differentiated by type, porosity and nitrate selectivity were used to compare the performance of nitrate removal. Gel type, Type 2 anion exchange resin was preferable when anion concentration of raw water was low. But efficiency of this resin decreased as flow rate increased. However, macroporous type resins were not affected by increasing flow rate. Macroporous resins were preferable when anion concentrations in raw water were high and high flow rate was proposed. And the general type resin showed better efficiency when sulfate concentrations were low. However the nitrate selective resin had better efficiency in treating raw water of high sulfate concentration. From the results, it may be drawn that nitrate selective resins are preferable to general type when a sulfate concentration in groundwater is over 50mg/l.

• Analytical Science and Technology
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• v.7 no.3
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• pp.329-338
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• 1994

The retention behaviors of natural gas components were studied on a single column by gas chromatography. The dead time, $t_0$ was obtained by using extrapolation of homologous series to determine capacity factors. The plots of retention data for homologous series and carbon number at different temperatures were shown to converge into a single point, which point was determined as a dead time. The results of the effect of temperature on the column efficiency for n-butane exhibited the plate number, N incerased with temperature, but the resolution among the fast eluted components decreased. The adsorption enthalpy (${\Delta}H^0{_{ads}}$) for each component on 28% DC 200 stationary phase was determined, and in order to investigate the retention behaviors of natural gas components the regression analysis of log $t_R$, log k' and log ${\alpha}$ vs. van der Waals volume(Vw), molecular connectivity index(X) and hydrophobic fragmental constant(f) were carred out. Good correlation was found between log k' vs. Vw, and log k' vs. f. The correlations between the physical properties of natural gas and the physical parameters were investigated by the linear regression analysis. The relationships between Vw vs. molecular weight and heating value(${\Delta}H_{comb}$), X vs. boiling point, and f vs. molecular weight, boiling point and heating value exhibited the high correlation coefficient more than 0.99. Using the regression equation between the heating value of natural gas and Vw the predicted heating values from $C_6$ to $C_{10}$ showed good agreement with those reported in the literature within 0.2% relative error.