• Journal of the Korean Data and Information Science Society
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• v.26 no.6
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• pp.1409-1416
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• 2015

The change of temperature influences on the various aspect, especially human health, plant and animal's growth, economics, industry, and culture of the country. In this article, the autoregressive error (ARE) model has been considered for analyzing the monthly temperature data at the Suwon monitoring site in Korea. In the ARE model, five meteorological variables, four greenhouse gas variables and five pollution variables are used as the explanatory variables for the temperature data set. The five meteorological variables are wind speed, rainfall, radiation, amount of cloud, and relative humidity. The four greenhouse gas variables are carbon dioxide ($CO_2$), methane ($CH_4$), nitrous oxide ($N_2O$), and chlorofluorocarbon ($CFC_{11}$). And the five air pollution explanatory variables are particulate matter ($PM_{10}$), sulfur dioxide ($SO_2$), nitrogen dioxide ($NO_2$), ozone ($O_3$), and carbon monoxide (CO). Among five meteorological variables, radiation, amount of cloud, and wind speed are more influence on the temperature. The radiation influences during spring, summer and fall, whereas wind speed influences for the winter time. Also, among four greenhouse gas variables and five pollution variables, chlorofluorocarbon, methane, and ozone are more influence on the temperature. The monthly ARE model explained about 43-69% for describing the temperature.

• Journal of the Korean Data and Information Science Society
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• v.24 no.4
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• pp.763-771
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• 2013

Due to a decrease in the number of college prep students which was triggered by the low birth rate since 1990, it is predicted, beginning 2016, that the entrance quota for colleges will exceed the number of applicants for college admissions. This serious imbalance between supply and demand raises serious problems for the regional universities, many of which have already been struggling to recruit new students and even considered closing down the schools. In an effort to securing best high school students, many of the schools have been developing various unique and specialized selectional processes for the applicants. In this research, through a statistical analysis of special admission processes for vocational high school students who were admitted to a regional state-run university (University A), I tried to find a way to effectively deal with the student management. Statistically analyzing these first-year students' enrollment and their adjustment processes as well as the departmental relationships and gender differences, I tried to find some better ways to secure good applicants. It is expected that this study will not only be utilized as guide to adopt a way to bypass the enrollment quota in order to secure talented students but also be served as a reference that will help the students adapt themselves to school life until they graduate. It is also expected that this study will be expanded in such a way as to compare it with other models and even develop a new type of college entrance system that would fit future college admission policies.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.65-71
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• 2020

Feature normalization is a method to reduce the effect of environmental mismatch between the training and test conditions through the normalization of statistical characteristics of acoustic feature parameters. It demonstrates excellent performance improvement in the traditional Gaussian mixture model-hidden Markov model (GMM-HMM)-based speech recognition system. However, in a deep neural network (DNN)-based speech recognition system, minimizing the effects of environmental mismatch does not necessarily lead to the best performance improvement. In this paper, we attribute the cause of this phenomenon to information loss due to excessive feature normalization. We investigate whether there is a feature normalization method that maximizes the speech recognition performance by properly reducing the impact of environmental mismatch, while preserving useful information for training acoustic models. To this end, we introduce the mean and exponentiated variance normalization (MEVN), which is a compromise between the mean normalization (MN) and the mean and variance normalization (MVN), and compare the performance of DNN-based speech recognition system in noisy and reverberant environments according to the degree of variance normalization. Experimental results reveal that a slight performance improvement is obtained with the MEVN over the MN and the MVN, depending on the degree of variance normalization.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.663-671
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• 2006

This study was performed for exploring the spatial distribution pattern of Pinus densiflora and Quercus spp. in Korea. Firstly, the spatial distribution map of Pinus densiflora and Quercus spp. was prepared in grid of $100m{\times}100m$ at national level, using digital forest type map and actual vegetation map. And thematic maps for topography, climate, and soil were also prepared in the raster form of $100m{\times}100m$. Through GIS based spatial analysis of the digital distribution map of Pinus densiflora and Quercus spp. and thematic maps, the spatial characteristics of Pinus densiflora and Quercus spp. distribution was explored in relation to the environmental factors such as topography, climate, and soil. And the occurrence frequency models of Pinus densiflora and Quercus spp. were derived. Pinus densiflora occurs more often than Quercus spp. at low elevation, low slope gradient, and high temperature areas. In addition, Pinus densiflora is mainly distributed at shallow and well-drained loamy soil from igneous rocks. In contrast, Quercus spp. is more common at shallow and well-drained loamy soil from metamorphic rocks. As a result, the prediction model for the spatial distribution of Pinus densiflora and Quercus spp. by topographical variables has proven successful with high statistical significance. The result of this study can contribute to rational management of Pinus densiflora and Quercus spp. stand in Korea, considering environmental factors such as topography, climate, and soil.

• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.4
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• pp.788-799
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• 1996

The purpose of this study was to determine the accuracy of the prediction methods which are frequently used in the clinic, such as Moyers', Tanaka and Johnston's, Song's Hixon and Oldfather's, Kaplan's, Smith's. These prediction methods were compared to the data, which were obtained from 100 Kyung-Hee University students (50 males and 50 females) with normal occlusion of permanent dentition, using a retrospective statistical analysis. The standard periapical radiopgraphs for the lower premolars using 16-inch long cone technique and the yellow stone dental casts were taken from each samples. The mesiodistal widths of 4 incisors, canine, premolars were measured on the dental casts, and those of premolars were measured on the radiographs. The correlation coefficients, paired samples t-tests, regression coefficients between the actual measuredments of the samples and the predicted measurements of each methods were analyzed. The results obtained were as follows: 1. The prediction methods using periapical radiographs tended to show a stronger correlation than the methods using dental casts; the correlation coefficients between the actual widths of the lower canine and premolars and the predicted widths of the tested methods were higher in Smith, Kaplan, Hixon & Oldfater, and Tanaka & Johnston (p<0.001). 2. The Moyers' probability chart at 65 % showed a tendency toward the least difference between the actual measurements and the predicted widths of the lower canine and the premolars, and the methods of Smith, Kaplan, Tanaka & Johnston also showed a less difference. 3. By means of evaluation in correlation coefficients and paired smaples t-tests, the Smith and Tanaka & Johnston in male, and the Moyers' 65 % and Song in female showed a high tendency toward accurate methods. 4. The regression equations by models that are derived from the study were as follows: Male(Lt.) :Y=10.799+0.475X Femle(Lt.) :Y= 7.427+0.609X (Rt.) :Y=11.043+0.462X (Rt.) :Y= 8.475+0.556X 5. The regression equations by radiographs that are dericed from the study were as follows: Male(Lt.) :Y=6.5651+0.9720X Femle(Lt.) :Y=4.8656+1.0632X (Rt.) :Y=7.8610+0.9060X (Rt.) :Y=4.5483+1.0843X

• The Korean Journal of Community Living Science
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• v.16 no.2
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• pp.39-50
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• 2005

For the life quality improvement of rural elderly family placed in risk of frail, this study was investigated. Health habit, food habit, and dietary management were analyzed between elderly and middle aged family The subjects 1870 collected in 9 provinces 88 cities or guns by sampling with probability proportional to size(PPS). Questionnaire method was used. Survey was conducted by trained interviewers. Statistical analyses were performed using SAS(version 8.1). Chi-square tests and General Linear Models were used. The elderly families' characters were odd pair$(42.0\%)$, with patients$(17.6\%)$ and health examination per 1 or 2 years$(44.0\%)$. The elderly families' health habit: high of no-drink$(55.2\%)$ and low of smoke$(31.3\%)$ situation was better than those of middle aged families'. The states of diets of elderly family: having breakfast$(94.1\%)$ but 1-2 kinds$(17.7\%)$ or 3-4 kinds$(59.4\%)$ of side dishes allowed to guess lower status of food intake balance. Nutritional supplements$(27.5\%)$with tablets of vitamins$(63.5\%)$ were the most frequent states in elderly family. The aspects of dietary habit of elderly family: no instant foods$(72.6\%)$, no snack$(3.08\%)$ and no dine-out$(67.7\%)$ were significantly different with those of middle aged family. Dietary habit score(8.28/12 points) of elderly family was not significantly different with 8.22/12 points of middle aged family. Food purchase place of elderly family was mainly at traditional market$(43.6\%)$, but it was significantly different with super-market$(47.6\%)$ of middle aged family. In elderly family, traditional dish preparation was seldom$(49.8\%)$ except winter kimchi$(91.5\%)$, but significantly higher rate of in middle aged families' traditional dish preparation and winter kimchi$(94.5\%)$. From these results, more of snack, traditional dishes and dine-out were needed to improve quality of life for rural elderly.

• The Korean Journal of Community Living Science
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• v.16 no.2
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• pp.111-120
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• 2005

Recently, the number of elderly people in the rural area of Korea has increased remarkably and their food security has become deteriorated mainly due to the low economic status. To investigate the food security for the elderly people, relevant data were obtained by offering questionnaire to the rural elderly people who were engaging in traditional agricultural production for daily foods. The subjects of 1870 were collected in 9 provinces according to PPS(Probability Proportional to Size). Questionnaire contained the items of dietary habit, food cultivation, Production and Preservation, and the suey was conducted by trained interviewers. SAS (ver 8.1) was used for statistical analyses in which Chi-square tests and General Linear Models were made. Family of the elderly people was $45.4\%$ of the total and the characteristics of elderly families were that age of male head was 82.1 years and that of female was 67.7 years, and that $68.8\%$ of elderly women were working for family income or pocket money. The elderly families' food cultivation state was surveyed and they were pepper$(59.1\%)$, chinese cabbage$(61.91\%)$, and sesame$(48.6\%)$ for their own consumption. But, bean sprout$(6.5\%)$, tofu$(7.7\%)$ and egg$(5.1\%)$ showed low rate of cultivation for the family. The rate of cultivating chinese cabbage$(61.9\%)$, and sesame$(48.6\%)$ was significantly higher than that of middle aged family. At the status of fermented food production for the elderly family, Doenjang$(87.4\%)$ and Gochujang$(86.3\%)$ Kanjang$(84.0\%)$ Kimchi$(92.9\%)$ Jangachi$(27.6\%)$ and Meju$(91.61\%)$maintained higher rate than that of middle aged families' Food preservation of elderly families was low and there are just jam$(5.3\%)$ and bottled products$(1.4\%)$. A little higher rate was observed lot the preserved food such as alcohol$(9.9\%)$ and powder$(9.8\%)$. For the elderly family the score of food cultivation was 4.08/12 points and that of food preservation was 0.62/12 points. The score of fermented food production for elderly family was 10.24/12 points which was significantly different from that of middle aged family (9.58/12 points, p<0.001). This result suggests that for the elderly people food with more protein is needed for production.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.781-790
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• 2013

This research focuses on development of the conceptual cost estimation models for I.L.M box girder bridge. The current conceptual cost estimation for public construction projects is dependent on governmental average unit price references which has been regarded as inaccurate and unreliable by many experts. Therefore, there have been strong demands for developing a better way of conceptual cost estimating methods. This research has proposed three different conceptual cost estimating method for a P.S.C. girder bridge built with the I.L.M method. Model (I) attempts to seek the proper breakdown of standard works that are accountable for more than 95 percentage in total cost and calculates the amount of standard work's materials from the standard section and volume of I.L.M box girder bridge. Model (II) utilizes a correlation analysis (coefficient over 0.6 or more) between breakdown of standard works and input data that would be considered available information in preliminary design phase. Model(III) obtains conceptual estimating through multiple-regression analysis between the breakdown of standard works and all of input data related to them. In order to validate the clustering of coverage in the preliminary design phase, the variation of I.L.M cost coverage from multiple-regression analysis[model(III)] has been investigated which result in between -3.76% and 11.79%, comparing with AACE(Association for the Advancement of Cost Engineering) which informs its variation between -5% and +15% in the design phase. The model proposed from this research are envisioned to be improved to a great distinct if reliable cost date for P.S.C. girder bridges can be continually collected with reasonable accuracies.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.79-89
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• 1997

One of the strenuous problems in orthodontic procedures is postretention stability and retention against relapse. Many investigative trial had been done to disclose the factors associated with relapse and effective prescription to stave off, however, the nature of these jeopardies remained obscure. The objective was to investigate the long-term stability and quantitative changes of dental arches subsequently after Class I nonextraction treatment. Study models,cephalometric headfilms of 26 samples which were taken before, after teatment and postretention were employed to measure the interdental width of corresponding buccal teeth,overbite,overjet and the inclination of incisors and molars. Statistical analysis was carried to compare each measurements across the time period, and followings were brought around. 1. The quantitative amount of relapse in overbite presented positive correlation with the amount of changes through the treatment. 2. Stability of intercanine width was so far secure in the case the expansion had been done through. 3. The amount of changes in intercanine width of the lower regardless of expansion or contraction manifested less than the upper, however, the relapse ratio got high. 4. The upper and lower incisors were likely to be labioversive, and remained stable after retention. 5. The first molars of the upper and lower were conceivably tipped back immediately after treatment and returned to the original angulation. The expansion of intermolar width stayed stable across the time scheme after treatment It was suggested that the maintenance of intercanine width of lower was pertinent to perform the postretention stabilityv and the expansion of dental arch shoed be confined within physiologic boundaries of the patients.

• The Journal of Korean Association of Computer Education
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• v.23 no.1
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• pp.63-75
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• 2020

From the perspective of compliance with security policies by members of the organization, which is a major cause of security incidents, this study presented biased thinking as factors that affect compliance with security policies and verified the following: First, the impact of biased thinking on security policies on compliance with security policies is verified. Second, the participation of management, perceived risk, education and punishment of management will verify the adjustment effect of increasing or decreasing biased thinking. Finally, we have verified that compliance attitudes have a significant impact on compliance behavior. To this end, 157 people were surveyed, statistical analysis of research models and structural equations, and conformity analysis were conducted. Studies have shown that biased thinking has a negative effect on the attitude of compliance with information security. In addition, it was analyzed that the attitude of compliance with information security policy increases policy compliance behavior. On the other hand, the higher the perceived risk of information security, the lower the bias was the adjustment effect, but management's participation, education and punishment were found to have no adjustment effect.