• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.2
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• pp.119-128
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• 1994

There are three important regions im Multiple Objective Linear Programming (MOLP). One is the region of efficient solutions, another is the region of weight to be used for finding efficient solutions, the third is the region of efficient (nondominated) objective values. In this paper, first, we find the condition of extreme point in the region of efficient objective values. Second, we find that the sum of the dimension of the weight region and the dimension of efficient objective values region is constant. Using the above, it is shown that we find the shape and dimension of weight region corresponding to the given region or efficient objective values and vice versa.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.1
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• pp.33-37
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• 1984

The net enthalpy changes for the water desorption of sun-cured tobacco have been studied. In order to compare the values of net enthalpy changes for the samples at the same moisture contents, correlation analyses have been performed. The results are summarizing as followings : 1 . As temperature and water vapor pressure increased, equlibrium moisture content were approaching to the saturated vapor pressure of water. 2. The values of 1nP against the reciprocal of absolute temperature were linear for the water desorption of samples. 3. Multiple regression was analyzed to calculate the values of 1nP at the same moisture content. The significance of $x^2$-test for the multiple regression was 0.5%. 4. The values of net enthalpy changes for Basma were greater than those of Sohyang at the same moisture content.

• Korean Journal of Hydrosciences
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• v.6
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• pp.13-22
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• 1995

The augmenting hydrologic data using a correlation procedure has been used to improve the estimates of the mean and variance at the site of interest with short record when one or more near by sites with longer records are available. The variance of the unbiased maximum likelihood estimator of $ derived by Moran based on the multivariate normal distribytion is modified into the form of Matalas and Jacobs for the biveriate normal distribution to get the critical minimum values of the multiple correlation coefficient which give the improvement for estimating the variance at the site of interest. Those values are tabulated for various lengths of short records and the number of sites.

• Journal of the Korean association of regional geographers
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• v.2 no.2
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• pp.159-171
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• 1996

The aim of this study is which factors affect the commercial land values and how they act upon them through distribution of commercial land values by multiple regression analysis in Gwangju city. The major findings of this study are as follows: (1) The changes of commercial land values distribution in $1989{\sim}1996$, We see that the commercial area of higher land values extends following the main arterial road. This is related to urbanization in urban fringe while the decline of commercial land values occurs in city center with long history of commercial region. This is due to unsuitableness in rapid changes of commercial environment because of fragmented lots, old buildings. traffic congestion etc. (2) The regions where commercial land values greatly rose are the west in constructed the new planning city center of Sangmu-dong. and the south west in which is related to the extension of high density apartment and the location of big discount stores. (3) Through the changes in commercial land values distribution map. and road map, topographical map, we know that commercial land values is related to various factors; namely, distance from CBD, convenient traffic, reputation of commercial district, condition of a road, size of supplementary, a degree of commercial land use etc. (4) From the above related factor, six variables are extracted by operational definition. That is the spatial distance from the city center, the walking distance to a stopping place, the road width, the amount of bus traffic, the amount of pedestrian, the number of the shop. (5) Data of seven variables are collected on the highest values point of each Dong. We applicate multiple regression analysis with commercial land values as a dependent variable, extracted six variables as independent variables. (6) As a result of multiple regression on the determinants of commercial land values, the variables which is greatly related to commercial land values are the amount of pedestrain, the spatial distance from city center. We identify that two variables explain variance of the commercial land values by 65%. (7) In order to make clear about not explained 35%. we carry out analysis of residual. In consequence, we see small estimate in downtown area and large estimate in urban fringe. This feature is due to simple core structure of Gwangju city and limits of this regression model.

• Journal of Family Relations
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• v.22 no.4
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• pp.53-80
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• 2018

Objectives: The purpose of this study was to investigate individual awareness variables influencing emotional, normative, and functional marriage intentions of unmarried men and women. Independent variables were values of offspring, perceptions to unmarried life, attitudes toward multiple role planning, perceptions and availabilities of marriage-related policies, views on the marriageable age, psychological burdens of pressure to marriage by significant people, and views on parents' support for marriage fund. Method: 553 unmarried men and women in Daegu, Korea were surveyed, and the data were analyzed using descriptive statistics, factor analysis, multivariate analysis of variance(MANOVA), multiple regression analysis, and hierarchical regression analysis with SPSS 22.0. Results: First, this study was more exploratory and in-depth approach to marriage intentions than precedent studies. The sub factors of marriage intentions were emotional, normative, and functional marriage ones. Second, emotional marriage intention showed significant differences depending on gender, dating, views on the marriageable age, and degree of acceptance of parents' support for marriage fund. Among the individual awareness variables, values of offspring, perceptions to unmarried life, attitudes toward multiple role planning, and psychological burdens of pressure to marriage personally or by friends influenced emotional marriage intention. Third, normative marriage intention showed significant differences depending on gender, religion, occupational status, employment condition, dating, views on the marriageable age, and degree of acceptance of parents' support for marriage fund. Among the individual awareness variables, values of offspring, perception to unmarried life, attitudes toward multiple role planning, view on the marriageable age, availabilities of marriage-related information offering policies, and psychological burdens of pressure to marriage by mother influenced normative marriage intention. Fourth, functional marriage intention showed significant differences depending on gender, job, parents' support for marriage fund, views on the marriageable age, and degree of acceptance of parents' support for marriage fund. Among the individual awareness variables, functional marriage intention was influenced by values of offspring, perception about unmarried life, attitudes toward multiple role planning, and degree of acceptance of parents' support for marriage fund. Finally, the hierarchical regression analysis showed that individual awareness variables influenced on marriage intentions. Especially, values of offspring, perceptions to unmarried, and attitudes toward multiple role planning influenced on emotional, normative, and functional marriage intentions in common. Conclusions: The findings from these analyses suggest that the selective process based on the individual awareness has become very significant to having marriage intentions. Therefore, this study will contribute as the basic data on national marriage-related policies. Furthermore, this study will be able to use to think about the marriage intention as a task to be preceded by the national policy in order to prepare for Korea 's low fertility and aging phenomenon.

• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.419-424
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• 1991

This study was carried out to investigate; the alpha-fetoprotein, urea and free fatty acid in amniotic fluids and water filled multiple T-maze test of fetuses affected by Ethylenethiourea. The S.P.F. Sprague-Dawley female rats(10 weeks) were used in this study and these animals were divided into four groups; control group I (10mg/kg/day), group II(30mg/kg/day), group III(50mg/kg/day). The results obtained were summarized as follows; 1. In the water filled multiple T-maze test of F1 male rats, The time and errors from start point to goal point of 30mg/kg group are significantly(p<0.001) increased from control group in 3rd day of test. In F1 female rats of 2nd day and 3rd day of water filled multiple T-maze test, The time and some errors in 30mg/kg group are significantly (p<0.05) increased from control group. 2. Alpha-fetoprotein values of all treated groups(10mg/kg, 30mg/kg and 50mg/kg) were significantly(p<0.001) decreased from control values in the amniotic fluids. 3. Urea values of ammniotic fluids in 50mg/kg group are significantly increased from control group. 4. Free fatty acid values of ammniotic fluids in 50mg/kg group are significantly increased from control group.

• Industrial Engineering and Management Systems
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• v.9 no.2
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• pp.107-120
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• 2010

In today's uncertain economic environment, the evaluation of safety for investment alternatives is of practical importance in manufacturing companies. This paper examines a method of quantitatively evaluating profitability and risk for multiple alternatives using the total-cost unit-cost domain. The paper assumes such factors as unit sales price, sales and production volume, unit variable cost, fixed cost, and yield for each alternative. The paper incorporates the relationship between production capacity and demand, distinguishing between cases of production capacity surplus and shortage for each year over the entire planning horizon. The paper investigates the case in which the values of each factor independently move in the direction of decreasing profit each year, and clarifies the procedure of comparing safety among multiple investment alternatives on a single consolidated total-cost unit-cost domain. The difficulty of the problem lies in the method of consolidating multiple total-cost unit-cost domains into a single domain since the combination of years of capacity surplus and shortage depends upon the change values in each factor under consideration. A systematic method of evaluating profitability as well as risk is presented, and the validity of the proposed method is verified using a numerical example.

• Journal of the Korean Institute of Gas
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• v.22 no.2
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• pp.52-58
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• 2018

The flash point is one of the most important properties to characterize fire and explosion hazard of flammable liquid mixture. In this paper, the flash points of ternary liquid mixture, n-nonane+n-decane+n-tridecane system, were measured using Seta flash closed cup tester. The measured values were compared with the calculated values using Raoult's law and multiple regression analysis. The absolute average errors(AAE) of the results calculated by Raoult's law is $0.6^{\circ}C$. The absolute average errors of the results calculated by multiple regression analysis is $0.4^{\circ}C$. As can be seen from AAE, the calculated values based on multiple regresstion analysis were found to be better than those based on Raoult's law.

• Quantitative Bio-Science
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• v.36 no.1
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• pp.23-31
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• 2017

Datasets from DNA microarray experiments, which are in the form of large matrices of expression levels of genes, often have missing values. However, the existing statistical methods including the principle components analysis (PCA) and Hotelling's t-test are not directly applicable for the datasets having missing values due to the fact that they assume the observed dataset is complete in general. Many methods have been proposed in previous literature to impute the missing in the observed data. Troyanskaya et al. [1] study the k-nearest neighbor (kNN) imputation, Kim et al. [2] propose the local least squares (LLS) method and Rubin [3] propose the multiple imputation (MI) for missing values. To identify differentially expressed genes, we propose a new testing procedure when the missing exists in the observed data. The proposed procedure uses the Stouffer's z-scores and combines the test results of individual imputed samples, which are dependent to each other. We numerically show that the proposed test procedure based on MI performs better than the existing test procedures based on single imputation (SI) by comparing their ROC curves. We apply the proposed method to analyzing a public microarray data.

• Current Research on Agriculture and Life Sciences
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• v.24
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• pp.49-53
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• 2006

The objective of this study was to present regression equations between reservoir water quality and land use types of the watersheds. In order to derive regression equations, a multiple linear regression analysis was used using observed data from 88 reservoirs in the Kyungpook Provcince. The measured values of BOD, COD, T-N, and T-P were correlated with the areas of land use types. 23 regression equations were obtained for all the water quality items and watershed sizes. The results showed that 2 regression equations have the multiple correlation coefficient(MCC) above 0.90, 10 regression equations have the MCC values from 0.70 to 0.90, 9 equations have the MCC from 0.40 to 0.70, and 2 equations have the MCC from 0.20 to 0.40. The results of this study can be used to estimate reservoir water quality simply and quickly in the planning phase.