• Journal of Korean Ophthalmic Optics Society
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• v.12 no.4
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• pp.119-125
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• 2007

The aim of the present study was to compare the contrast sensitivity of soft contact lens wearers, spectacle wearers or emmetropia. Seventy myopic eyes and thirty emmetropic eyes aged 19 to 26 years were collected. The myopic group included 48 eyes corrected with spectacle lenses and 22 eyes of them corrected with contact lenses, too: all had corrected vision acuity of 20/20 or better. Spatial contrast sensitivity was measured using the OPTEC 6500 contrast sensitivity view-in tester included the EyeView　 Functional Vision Analysis software at photopic or mesoopic condition. There was no significant difference in contrast sensitivity between spectacle lenses and emmetropes. Myopes corrected with soft contact lenses showed statistical sensitivity losses at 1.5, 12 cycle/degree spatial frequencies. In conclusion, our findings suggest that loss of contrast sensitivity in soft contact lens wearers might be interpreted as evidence for corneal disruption before corneal pathological events occur in contact lens wearers. Contrast sensitivity testing appears to be a useful method for evaluating soft contact lenses.

• Clinical and Experimental Pediatrics
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• v.60 no.6
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• pp.189-195
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• 2017

Purpose: The purpose of this study was to investigate the effects of lamotrigine for the treatment of attention-deficit hyperactivity disorder (ADHD) symptoms in children with epilepsy. Methods: Pediatric patients newly diagnosed with epilepsy (n=90 [61 boys and 29 girls]; mean age, $9.1{\pm}3.4years$) were enrolled. All patients were evaluated with the Korean ADHD rating scale (K-ARS)-IV before treatment with lamotrigine and after doses had been administered. The mean interval of ADHD testing was approximately 12.3 months. The initial dosage of lamotrigine was 1 mg/kg/day (maximum 25 mg/day for the first 2 weeks), and increased by 1 mg/kg every 2 weeks until titrated up to 7 mg/kg/day (or maximum 200 mg/day). Results: The mean ADHD test score of the 90 subjects was $17.0{\pm}1.8$ at baseline. It was slightly reduced to $15.6{\pm}1.7$ after lamotrigine monotherapy (P>0.01). Prior to treatment, a total of 31 patients (34.4%) met the diagnostic criteria for ADHD according to Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision, Of these 31 patients, 27 (87.1%) had significantly improved ADHD scores with lamotrigine monotherapy ($28.0{\pm}1.6$ reduced to $18.1{\pm}2.6$, P<0.001). Among these 27 patients, 25 (92.6%) showed normalized electroencephalogram (EEG) and 26 (96.3%) achieved total freedom from seizures within 12 months of the initiation of lamotrigine monotherapy. Conclusion: The results from our study show that lamotrigine had a positive effect in pediatric epilepsy patients by reducing ADHD symptoms, preventing seizures, and normalizing EEG. However, further research is required to determine whether lamotrigine is efficacious against ADHD symptoms independent of its effects on epileptic seizures.

• The Korean Journal of Applied Statistics
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• v.21 no.6
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• pp.933-945
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• 2008

The genetic association test on age of onset trait aims to detect the putative gene by means of linear rank tests for a significant trend of onset distributions with genotypes. However, due to the selective sampling of recruiting subjects with ages less than a pre-specified limit, the genotype groups are subject to substantially different censored distributions and thus this is one reason for the low efficiencies in the linear rank tests. In testing the equality of two survival distributions, log-rank statistic is preferred to the Wilcoxon statistic, when censored observations are nonignorable. Therefore, for more then two groups, we propose a generalized log-rank test for trend as a genetic association test. Monte Carlo studies are conducted to investigate the performances of the test statistics examined in this paper.

• Korean Journal of Veterinary Research
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• v.50 no.1
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• pp.43-48
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• 2010

Animal disease surveillance system, defined as the continuous investigation of a given population to detect the occurrence of disease or infection for control purposes, has been key roles to assess the health status of an animal population and, more recently, in international trade of animal and animal products with regard to risk assessment. Especially, for a system aiming to determine whether or not a disease is present in a population sensitivity of the system should be maintained high enough not to miss an infected animal. Therefore, when planning the implementation of surveillance system a number of factors that affecting surveillance sensitivity should be taken into account. Of these parameters sample size is of important, and different approaches are used to calculate sample size, usually depending on the objective of surveillance systems. The purpose of this study was to evaluate the sensitivity of the current national serological surveillance programs for four selected bovine diseases assuming a specified sampling plan, to examine factors affecting the probability of detection, and to provide sample sizes required for achieving surveillance goal of detecting at least an infection in a given population. Our results showed that, for example, detecting low level of prevalence (0.2% for bovine tuberculosis) requires selection of all animals per typical Korean cattle farm (n = 17), and thus risk-based target surveillance for high risk groups can be an alternative strategy to increase sensitivity while not increasing overall sampling efforts. The minimum sample size required for detecting at least one positive animal was sharply increased as the disease prevalence is low. More importantly, high reliability of prevalence estimation was expected with increased sampling fraction even when zero-infected animal was identified. The effect of sample size is also discussed in terms of the maximum prevalence when zero-infected animals were identified and on the probability of failure to detect an infection. We suggest that for many serological surveillance systems, diagnostic performance of the testing method, sample size, prevalence, population size, and statistical confidence need to be considered to correctly interpret results of the system.

• Journal of the Korea Society of Computer and Information
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• v.12 no.2 s.46
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• pp.315-324
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• 2007

This study is to investigate the relationships between system characteristics and performance of customer relationship management, and also to examine the type of industry which organizations are involved in, financial or non-financial business, affects on those relationships. To accomplish these research purposes, this study obtained 230 questionnaires from domestic organizations which have implemented customer relationship management systems, and finally used 206 responses for statistical analyses. The results of the study can be summarized as followings. First, integration of system and ease of use of system among various system characteristics have a positive affect on the performance of customer relationship management in significant level. Second, the relationship between system characteristics and performance of customer relationship management, based on testing for parallelism, does not differ by the industry type of organizations.

• The Journal of Korean Physical Therapy
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• v.24 no.4
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• pp.268-275
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• 2012

Purpose: This study is to identify how eye movement influences the static balance and fall efficacy of the elderly who have experienced fall-related injuries. Methods: Thirty nine elderly who scored 24 points in the Korean mini mental state examination, were able to walk, and had no specific disease, were selected as the research subjects among elderly who have experienced fall-related injury more than once in the past year. Thus, 20 for the experimental group, and 19 for the control group were selected as subjects. The experiment was conducted for 6 weeks, including periods of evaluation before and after intervention. Results: The results with respect to the dependent variables are as follows: Substitute sample t-testing showed significant differences between each group in eye movement to check difference in balance performance and fall efficacy. When independent sample t-tests were conducted to compare static balancing performance and fall efficacy between the two groups after intervention, they showed significant differences in statistical terms (p<0.05). Conclusion: From the above results of the study, it was found that the application of eye movement combined with diverse fall prevention programs is effective, when enhancing static balance performance power and improving fall efficacy.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.11-18
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• 2008

In recent, lots of researches for mechanical-empirical design concept for asphalt pavement are on going. AASHTO 2002 Design Guide in USA and KPRP(Korean Pavement Research Program) in Korea are under developing. In these programs, the mechanical properties of hot mix asphalt are a key role for design and analysis. Unfortunately, there is no proper database on the mechanical properties of hot mix asphalt, such as dynamic modulus. The use of dynamic modulus has couple of good advantages which is based on temperature, traffic loading and frequency on pavement. In this research, the verification of the relationship between maximum nominal aggregate size and dynamic modulus has been carried out. Also, test specimen size effect on dynamic modulus has been conducted. Considering the limitation of laboratory testing machine in Korea, test specimen with 100mm diameter and 150mm height is recommended for dynamic modulus test. Also, as the maximum nominal aggregate size increases, the dynamic modulus of hot mix asphalt increases.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.79-97
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• 2010

The purpose of this research is to apply the neural networks models for the hydrologic disaggregation of the yearly pan evaporation(PE) data in Republic of Korea. The neural networks models consist of multilayer perceptron neural networks model(MLP-NNM) and support vector machine neural networks model(SVM-NNM), respectively. And, for the evaluation of the neural networks models, they are composed of training and test performances, respectively. The three types of data such as the historic, the generated, and the mixed data are used for the training performance. The only historic data, however, is used for the testing performance. The application of MLP-NNM and SVM-NNM for the hydrologic disaggregation of nonlinear time series data is evaluated from results of this research. Four kinds of the statistical index for the evaluation are suggested; CC, RMSE, E, and AARE, respectively. Homogeneity test using ANOVA and Mann-Whitney U test, furthermore, is carried out for the observed and calculated monthly PE data. We can construct the credible monthly PE data from the hydrologic disaggregation of the yearly PE data, and the available data for the evaluation of irrigation and drainage networks system can be suggested.

• Proceedings of the KACD Conference
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• 2008.05a
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• pp.224-234
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• 2008

The purpose of this study was to compare the normal and two times of application time of six self-etching primers applied to enamel using microshear bond strength (uSBS) test and the finding of scanning electronic microscope (SEM). Crown of sixty human molars were bisected mesiodistally and buccal and lingual enamel of crowns were partially exposed and polished with 600 grit SiC papers. They were divided into one of two equal groups subdivided into one of six equal groups (n = 10) by self-etching primer adhesives. After the same manufacture's adhesive resin and composites were bonded on the enamel surface of each group, the bonded specimens were subjected to uSBS testing and also observed under SEM. In conclusion, generally two times of primer application time increased the enamel uSBS, especially with the statistical increase of bond strength in adhesives involving high-pH primers.

• Journal of the Korean Society of Clothing and Textiles
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• v.9 no.1
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• pp.17-27
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• 1985

In order to investigate the warmth retaining properties of fabrics some characteristics such as thickness. porosity, packing density, thermal conductivity, moisture regain and air permeability were measured and experimental results were analysed statistically to relate the warmth retaining properties with those characteristics. From the analysis, the following results were obtained. 1. When the warmth retaining properties of fabrics (Y) are dependent variable and thickness ($x_1$), porosity ($x_2$), packing density ($x_3$), thermal conductivity ($x_4$), moisture regain ($x_5$) and air permeability ($x_6$) are independent variables, the regression equation of warmth retaining properties can be represented as follows. 1) Y= 1.6005+46.817$x_1$, (R=0.9487) 2)Y=-1.4187+26.5072$x_1$+0.2055$x_2$(R=0.9704) 3) Y= -3.6908+17.4482$x_1$+0.1782$x_2$+28.3243$x_3$ (R=0.9756) 4) Y=0.9202+16.9553$x_1$+0. 1167$x_2$+30.3577$x_3$+1.8884$x_4$ (R=0.9792) 5) Y=0.9353+17.2266$x_1$+0.1177$x_2$+28.9821$x_3$-1.8302$x_4$+0.0151$x_5$ (R=0.9792) 6) Y=0.7583+17.2343$x_1$+0.1196$x_2$+28.8830$x_3$-1.8336$x_4$+0.0187$x_5$0.0004$x_5$ (R=0.9792) 2. The warmth retaining properties of fabrics are merely affected by adding thermal conductivity, moisture regain and multiple regression equation which contains thickness, porosity and packing density as variables. Therefore the multiple regression which contains thickness, porosity and packing density as variables Y=-3.6908+17.4482$x_1$+0.1782$x_2$+28.3243$x_3$ is highly practical.