• International Journal of Computer Science & Network Security
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• v.21 no.5
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• pp.23-30
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• 2021

In recent years, hazardous flash flooding has caused deaths and damage to infrastructure in Saudi Arabia. In this paper, our aim is to assess patterns and trends in climate means and extremes affecting flash flood hazards and water resources in Saudi Arabia for the purpose to improve risk assessment for forecast capacity. We would like to examine temperature, precipitation climatology and trend magnitudes at surface stations in Saudi Arabia. Based on the assessment climate patterns maps and trends are accurately used to identify synoptic situations and tele-connections associated with flash flood risk. We also study local and regional changes in hydro-meteorological extremes over recent decades through new applications of statistical methods to weather station data and remote sensing based precipitation products; and develop remote sensing based high-resolution precipitation products that can aid to develop flash flood guidance system for the flood-prone areas. A dataset of extreme events has been developed using the multi-decadal station data, the statistical analysis has been performed to identify tele-connection indices, pressure and sea surface temperature patterns most predictive to heavy rainfall. It has been combined with time trends in extreme value occurrence to improve the potential for predicting and rapidly detecting storms. A methodology and algorithms has been developed for providing a well-calibrated precipitation product that can be used in the early warning systems for elevated risk of floods.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.3 s.31
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• pp.134-145
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• 2006

Objective : This study was carried out to investigate what type of assumption and conditions are needed for the application of various statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test and to evaluate that they are used correctly in the research process. Methods : One more methods of statistical analysis were used in 91 papers among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatology from April 2003 to December 2005. So we analysed the type of statistical analysis method in 91 papers(clinical and experimental study) and assessed the their validity of statistical techniques by the check list consisting of 34 items(3 items for validity assessment of descriptive statistics, 6 items for t-test, 7 items for analysis of variance, correlation analysis and regression analysis, respectively, 4 items for chi-square test) Results : 1. The type of 65(40%) cases is experimental trial, the type of 55(34%) cases is case report, the type of 26(16%) cases is clinical trial and the type of 16(10%) cases is review, in 91 papers using statistical techniques among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatol-ogy from April 2003 to December 2005. 2. One more methods of statistical analysis were used in the experimental and clinical study. When we classified 125 units using statistical analysis methods in 91 papers according to statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test, the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of one way ANOVA is 15(12%), the number of non-parametric test 10(8%). 3. After carrying out one way ANOVA, the number of using multiple comparison methods is 15(Scheffe:6(26%), Duncan:4(17%), Dunnett:3(13%), Tukey:2(9%)) out of 23 (total case carrying out one way ANOVA). 8(35%) out of 23 did not enforce multiple comparison methods after carrying out one way ANOVA. 4. From the assessment of validity about 63 cases using statistical techniques(except descriptive statistics), 5(8%) cases are proper, the other 58(92%) are improper, so we recognized a serious misuse of statistical application in our journal. 5. The number of case below 10 sample size in experimental and clinical study(except descriptive statistics) is 31(34%) and frequent. Also the number of case containing no mention of sample size is 41(45%, including culture study). 6. For example of statistical error, there are wrong choice of statistical technique, lack of check on standard assumption(such as standard distribution, equivariance, independence), and so on. Conclusions : We investigated the validity of statistical analysis methods in our journal by check list consisting of 34 items and suggested correct statistical analysis methods. We should practice the spread of education about statistical analysis methods and precis application, enhance objectivity and reliability of our thesis and further correspond with purpose of scientific study.

• Journal of the Korean School Mathematics Society
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• v.14 no.3
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• pp.295-323
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• 2011

This study is based on the recognition that teacher educators have to focus their attention on developing pre-service teachers' statistical reasoning for statistics education of school mathematics. This paper investigated knowledge on pre-service teachers' statistical reasoning. Statistical Reasoning Assessment (SRA) is performed to find out pre-service teachers' statistical reasoning ability. The research findings are as follows. There was meaningful difference in the statistical area of statistical reasoning ability with significant level of 0.05. This proved that 4 grades pre-service teachers were more improve on statistical reasoning than 2 grades pre-service teachers. Even though most of the pre-service teachers ratiocinated properly on SRA, half of pre-service teachers appreciated that small size of sample is more likely to deviate from the population than the large size of sample. A few pre-service teachers have difficulties in understanding "Correctly interprets probabilities(be able to explain probability by using ratio" and "Understands the importance of large samples(A small sample is more likely to deviate from the population)".

• The Journal of Engineering Geology
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• v.32 no.3
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• pp.327-338
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• 2022

This study aims to empirically and statistically predict soil depths across areas affected by landslides. Using soil depth measurements from a landslide area in Korea, two sets of soil depths are calculated using a Z-model based on terrain elevation and a probabilistic statistical model. Both sets of calculation results are applied to derive landslide risk using the saturated infiltration depth ratio of the soil layer. This facilitates analysis of the infiltration of rainfall into soil layers for a rainfall event. In comparison with the probabilistic statistical model, the Z-model yields soil depths that are closer to measured values in the study area. Landslide risk assessment in the study area based on soil depth predictions from the two models shows that the percentage of first-grade landslide risk assessed using soil depths from the probabilistic statistical model is 2.5 times that calculated using soil depths from the Z-model. This shows that soil depths directly affect landslide risk assessment; therefore, the acquisition and application of local soil depth data are crucial to landslide risk analysis.

• Therapeutic Science for Rehabilitation
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• v.6 no.2
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• pp.59-70
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• 2017

Objective: It is important to assess the participation and understand the characteristics of participation for setting goal of the child's treatment and strengthening participation. In this study, we verified the validity of the LIFE-H 1.0, so that domestic occupational therapists can systematically evaluate children's participation. Methods: This study was conducted for about 2 months from February to April 2016 in 47 children with disabilities and non-disabled children. We divided the children into two groups aged 0-4 years and 5-13 years old and conducted a self-report questionnaire to parents. The collected data were verified by SPSS(Statistical Package for Social Science) statistical analysis program. Results: There was no difference between the two groups in general characteristics. In comparison of two groups, a significant difference(p<.05) was found in the LIFE-H 1.0 total performance and satisfaction score and the high discriminant validity was verified. Conclusion: The ultimate goal of occupational therapy is to increase participation. Therefore, the occupational therapist must be able to assess the level of participation and than set the goal of intervention. This study confirms the high level of validity and expects that Korean version of LIFE-H 1.0 will be widely used in clinical field and research.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.1
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• pp.1-6
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• 2011

The underlying principle of environmental conservation and restoration is to receive continuous services from nature. In this context, the basic objective of oil spill response and recovery activities is to allow affected residents to retain sustainability of their daily livelihood and productive environment. Hence, monitoring the status of socio-economic impact and the extent of restoration is an important parameter in the restoration effort to repair the damaged functions of environmental services with oil spill accident. However, assessment of socio-economic impact poses investigators with much difficulties in selecting the most appropriate approaches because the process often involves various stakeholders, directly and indirectly. Moreover, the analyses and interpretation of the results also pose a great challenge. The present study monitored fisheries and tourism numbers which were considered as major local socio-economic indicators of living and production environment affected by M/T Hebei Spirit oil-spill accident. This monitoring was conducted by examining the published papers and statistical reports. This was supplemented by surveying how the local residents actually felt about the damage and recovery for the first time in Korea. The results showed that the rate of the recovery was about 40~50 %, and the rate of the recovery seemed to be slowed or decreased. However, what the local residents actually felt was 2~10 points less than the literature surveys and statistical reports. These results suggested limits to using only the literature and statistical surveys for the traditional socio-economic impact assessment. The study also showed the need to include in the impact assessment process what and how the local residents actual feel about the oil spill damage and recovery process.

• Journal of Environmental Impact Assessment
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• v.14 no.4
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• pp.165-177
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• 2005

This study was carried out to offer the basic methodology of the system and model to objectively assess the natural ecosystem for environmentally friendly land conservation and present the alternative plan on establishing the environmental policy. The results of this study were as follows. We selected four assessment factors associated with biotic, abiotic, qualitative, and functional factors. Also, there were extracted fifty-six indicators including density, total nitrogen, hemeroby degree, and goods production. The assessment factor showed that biotic one was very important. The importance of indicators were analyzed that rare and endangered plant was important in biotic factor, in case of abiotic, qualitative, and functional factors, organic matter, landscape diversity, and conservation of ecosystem were greatly important. The results of factor analysis on the characteristics of indicators, classified biotic factor into six factors including a structural one, abiotic factor as a soil and physical one, qualitative factor as five ones including hierarchical one, and functional factor as public and conservational one. In the results of analysis on assessment model, R-square of biotic factor was 51.7%, those of abiotic, qualitative, and functional one were each 58.4%, 44.2%, and 39.3%, and statistical problem was no existence. In future, to develop the assessement model and methodology of sustainable natural ecosystem, we will have to achieve the integrated model and grouping by assessment factor.

• Korean Journal of Child Studies
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• v.26 no.2
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• pp.27-41
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• 2005

The purpose of this study was to test the reliability and validity of the Infant Montessori Performance Assessment Scales developed by the authors. Subjects of the study consisted of 132 Montessori teachers and 50 infants who were attending Montessori home school throughout the whole country, using census method. Infant's age ranged from 6 to 24 months. Data were analysed by using SAS 8.2 PC program. Statistical methods employed were frequency, Cronbach's alpha, Kappa coefficient, test-retest correlation, construct validity, and concurrent validity. The Cronbach's alpha of 6 sub-scales included physical, creativity, practical life, sense, language, and cognitive education, which ranged from .70 to .86. And the! correlation of the test/re-test was .72. The correlation between the 6 sub-scales of Infant-Montessori Performance Assessment Scales and the total scores of 6 items ranged from .06 to .84. Therefore, the construct validity of Infant Montessori Performance Assessment Scales was verified. The Kappa coefficient of inter-rater reliability was .76. The correlation between the Infant Montessori Performance Assessment Scales and the Standardized Korean Creativity Traits Checklist(K-CTC) and the Korean Child Social Maturity Scales showed non-significant levels of .16 and .12 respectively. Conclusively, Infant Montessori Performance Assessment Scales developed by the authors were verified through the above reliability and validity tests. Specifically the Infant Montessori Performance Assessment Scales showed the relationship of the convergent and divergent validity with the Korean Child Social Maturity Scales and the Standardized Korean Creativity Traits Checklist, respectively.

• Journal of Environmental Impact Assessment
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• v.29 no.4
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• pp.272-285
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• 2020

We investigated statistical evaluation parameters for 3D meteorological and air quality models and selected several quantitative indicator references, and summarized the reference values of the statistical parameters for domestic air quality modeling researcher. The finally selected 9 statistical parameters are MB (Mean Bias), ME (Mean Error), MNB (Mean Normalized Bias Error), MNE (Mean Absolute Gross Error), RMSE (Root Mean Square Error), IOA (Index of Agreement), R (Correlation Coefficient), FE (Fractional Error), FB (Fractional Bias), and the associated reference values are summarized. The results showed that MB and ME have been widely used in evaluating the meteorological model output, and NMB and NME are most frequently used for air quality model results. In addition, discussed are the presentation diagrams such as Soccer Plot, Taylor diagram, and Q-Q (Quantile-Quantile) diagram. The current results from our study is expected to be effectively used as the statistical evaluation parameters suitable for situation in Korea considering various characteristics such as including the mountainous surface areas.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.91-105
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• 1999

Spatial data integration using multiple geo-based data sets has been regarded as one of the primary GIS application issues. As for this issue, several integration schemes have been developed as the perspectives of mathematical geology or geo-mathematics. However, research-based approaches for statistical/quantitative assessments between integrated layer and input layers are not fully considered yet. Related to this niche point, in this study, spatial data integration using multiple geoscientific data sets by known integration algorithms was primarily performed. For spatial integration by using raster-based GIS functionality, geological, geochemical, geophysical data sets, DEM-driven data sets and remotely sensed imagery data sets from the Ogdong area were utilized for geological thematic mapping related by mineral potential mapping. In addition, statistical/quantitative information extraction with respective to relationships among used data sets and/or between each data set and integrated layer was carried out, with the scope of multiple data fusion and schematic statistical assessment methodology. As for the spatial integration scheme, certainty factor (CF) estimation and principal component analysis (PCA) were applied. However, this study was not aimed at direct comparison of both methodologies; whereas, for the statistical/quantitative assessment between integrated layer and input layers, some statistical methodologies based on contingency table were focused. Especially, for the bias reduction, jackknife technique was also applied in PCA-based spatial integration. Through the statistic analyses with respect to the integration information in this case study, new information for relationships of integrated layer and input layers was extracted. In addition, influence effects of input data sets with respect to integrated layer were assessed. This kind of approach provides a decision-making information in the viewpoint of GIS and is also exploratory data analysis in conjunction with GIS and geoscientific application, especially handing spatial integration or data fusion with complex variable data sets.