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The Study on Standard Bodytype for Korean Women between the ages of 18 and 24 years old(Part I) -focusing on the analysis of the High-frequency type and the High-frequency range- (18~24세 한국인 여성의 표준체형에 관한 연구(제1보) -다빈도유형 및 다빈도구간에 대한 분석을 중심으로-)

  • 이정임;남윤자
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.5
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    • pp.630-641
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    • 2002
  • The purpose of this study is to suggest the standard of bodytype which offers various data with regard to three-dimensional characteristics of body, and which offers the criterion for the sizes and shapes to interpret various bodytypes, to estimate filling, and to construct ready-made clothing. In this study, standard bodytype was defined as a typical type with beautiful proportion and shape which a large number of people have, too. In order to continue this study, there were two ways of analyzing bodytypes of subjects in the view of statistics and beauty. We primarily carried on statistical analysis in this report. Taken as a sample, the subjects were ninety-seven females who were between the ages of 18 and 24 years o1d. They were measured on November 1999. The data of seven hundred and few females, 18∼24 year-old, from the National Somatometry Survey of 1997 were used for analysis, too. Three kinds of classification methods were used for statistical analysis. The first method was based on the lateral view of the body, the second was based on the Factor and Cluster analysis of the photographic measurements of each of the anterior and lateral body, and the third was based on the Factor and Cluster analysis of the anthropometric measurements of the whole body. From the analysis on the distribution of R hrer Index the difference of width, the difference of depth, the proportion of height and head height, the High-frequency Proportion(H.P.)range were selected. The straight type from the lateral view, High-frequency type from each method, and subjects in H.P. range were compared with each other. As the result, it was confirmed that it is proper to base on the size and shape of subjects in H.P. range to analyze the standard bodytype.

An Investigation of the Selection Process of Mathematically Gifted Students

  • Lee, Kyung-Hwa;Park, Kyung-Mee;Yim, Jae-Hoon
    • Research in Mathematical Education
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    • v.7 no.3
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    • pp.139-150
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    • 2003
  • The purpose of this paper is to review the gifted education from a reflective perspective. Especially, this research touches upon the issues of selection process from a critical point of view. Most of the problems presented in the mathematics competition or in the programs for preparing such competitions share the similar characteristic: the circumstances that are given for questions are too artificial and complicated; problem solving processes are superficially and fragmentally related to mathematical knowledge; and the previous experience with the problem very much decides whether a student can solve the problem and the speed of problem solving. In contrast, the problems for selecting students for Gifted Education Center clearly show what the related mathematical knowledge is and what kind of mathematical thinking ability these problems intend to assess. Accordingly, the process of solving these problems can be considered an important criterion of a student's mathematical ability. In addition, these kinds of problems can encourage students to keep further interest, and can be used as tasks for mathematical investigation later. We hope that this paper will initiate further discussions on issues derived from the mathematically gifted student selection process.

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A Study of Antibiotic Resistance of Enterococci Isolated from Recycling Water of Floor Fountains in Gwangju Area (광주지역내 바닥분수 재이용수에서 분리한 장구균의 항생제 내성 연구)

  • Kim, Yeon-Hee;Song, Hyeong-myeong;Choi, Yeong-Seop;Lee, Yoon-Kook;Park, Jin-Hwan;Kim, Sun-Jung;Kim, Ha-Ram;Kang, Yu-Mi;Bae, Seok-Jin;Cho, Yong-Gwan
    • Journal of Environmental Health Sciences
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    • v.45 no.3
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    • pp.222-230
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    • 2019
  • Objectives: This study aims to evaluate water quality in terms of microorganisms and identify the antibiotic resistance of Enterococci isolated from the recycling water in floor fountains at three parks and one reservoir in the Gwangju area. Methods: Water samples were analyzed for Enterococci using membrane Enterococcus indoxyl ${\beta}$ d glucoside agar (mEI) as described in USEPA Method 1600. The vancomycin-resistant Enterococci with VanA and VanB were identified by PCR. An examination of the antibiotic resistance of isolates against 14 antibiotics was performed by the disk diffusion method. Results: The drinking water quality criterion was exceeded for total colony counts in 68% of all recycling water samples. The average concentration of total califorms and fecal coliforms was 139,325 and 413 CFU/100 mL, respectively. VanA and VanB were not detected from the isolates. We found the antibiotic resistant Enterococci strains to be E. faecalis, E. faecium, E. durans, E. mundtii, E. hirae, and E. thailandicus. The isolates were resistant to Rifampin (50%), Erythromycin (25.8%), Tetracycline (10.2%), Nitrofurantoin (8.1%), Minocycline (3.1%), Erythromycin (1.2%), Penicillin (0.7%), Norfloxacin (0.5%), and Teicoplanin (0.5%) among the 14 antibiotics tested. Antibiotic resistance tests for Enterococci from the recycling water of floor fountains resulted in 30.2% showing resistance to two or more antibiotics. Conclusions: These results showed that the multi-antibiotic resistance of Enterococci, E. coli, and others should be investigated continuously in each environment field.

Hardness and Rebound Properties of Sprayed Green Soil Produced with Functional Additives for the Application to Steep Slopes (기능성 첨가재를 적용한 급경사면용 녹생토의 경도 및 리바운드 특성)

  • Lee, Byung-Jae;Kim, Hyo-Jung;Kim, Yun-Yung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.258-264
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    • 2018
  • In this study, the improved performance of sprayed green soil was evaluated by incorporating functional additives. The optimal mixing ratio of the thickener and super-absorbent polymer, as an additive for moisture supply to the growth of plants within the range of mixing ratios that gives sufficient strength of green soil, was 5% and 1%, respectively. Using Portland cement as a main binder, the pH of the green soil was 9.1. To solve this alkali problem, the mixing proportion was improved so that the pH of the green soil was approximately 7.2 by mixing more than 10% of the chelate resin. The soil conductivity was measured to be 280 ~ 350mS/m under all the mixing conditions. This satisfied the criterion of less than 1000mS/m on the slope surface. As a result of measuring the soil hardness of the green soil prepared under the optimal mixing conditions of functional additives, it satisfied the criteria of 18 ~ 23mm when sprayed under a 1 bar pressure. The rebound rate was less than 15% when spraying green soil on a 75 % slope, and the hardness of the sprayed green soil was more than 18 mm.

Mechanical model for analyzing the water-resisting key stratum to evaluate water inrush from goaf in roof

  • Ma, Kai;Yang, Tianhong;Zhao, Yong;Hou, Xiangang;Liu, Yilong;Hou, Junxu;Zheng, Wenxian;Ye, Qiang
    • Geomechanics and Engineering
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    • v.28 no.3
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    • pp.299-311
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    • 2022
  • Water-resisting key stratum (WKS) between coal seams is an important barrier that prevents water inrush from goaf in roof under multi-seam mining. The occurrence of water inrush can be evaluated effectively by analyzing the fracture of WKS in multi-seam mining. A "long beam" water inrush mechanical model was established using the multi-seam mining of No. 2+3 and No. 8 coal seams in Xiqu Mine as the research basis. The model comprehensively considers the pressure from goaf, the gravity of overburden rock, the gravity of accumulated water, and the constraint conditions. The stress distribution expression of the WKS was obtained under different mining distances in No. 8 coal seam. The criterion of breakage at any point of the WKS was obtained by introducing linear Mohr strength theory. By using the mechanical model, the fracture of the WKS in Xiqu Mine was examined and its breaking position was calculated. And the risk of water inrush was also evaluated. Moreover, breaking process of the WKS was reproduced with Flac3D numerical software, and was analyzed with on-site microseismic monitoring data. The results showed that when the coal face of No. 8 coal seam in Xiqu Mine advances to about 80 m ~ 100 m, the WKS is stretched and broken at the position of 60 m ~ 70 m away from the open-off cut, increasing the risk of water inrush from goaf in roof. This finding matched the result of microseismic analysis, confirming the reliability of the water inrush mechanical model. This study therefore provides a theoretical basis for the prevention of water inrush from goaf in roof in Xiqu Mine. It also provides a method for evaluating and monitoring water inrush from goaf in roof.

Estimation of the Input Wave Height of the Wave Generator for Regular Waves by Using Artificial Neural Networks and Gaussian Process Regression (인공신경망과 가우시안 과정 회귀에 의한 규칙파의 조파기 입력파고 추정)

  • Jung-Eun, Oh;Sang-Ho, Oh
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.34 no.6
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    • pp.315-324
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    • 2022
  • The experimental data obtained in a wave flume were analyzed using machine learning techniques to establish a model that predicts the input wave height of the wavemaker based on the waves that have experienced wave shoaling and to verify the performance of the established model. For this purpose, artificial neural network (NN), the most representative machine learning technique, and Gaussian process regression (GPR), one of the non-parametric regression analysis methods, were applied respectively. Then, the predictive performance of the two models was compared. The analysis was performed independently for the case of using all the data at once and for the case by classifying the data with a criterion related to the occurrence of wave breaking. When the data were not classified, the error between the input wave height at the wavemaker and the measured value was relatively large for both the NN and GPR models. On the other hand, if the data were divided into non-breaking and breaking conditions, the accuracy of predicting the input wave height was greatly improved. Among the two models, the overall performance of the GPR model was better than that of the NN model.

Validation of the Korean Version of the Positive and Negative Ex-relationship Thoughts Scale (한국판 과거 연애 관계 사고 척도(Positive and Negative Ex-Relationship Thoughts Scale) 타당화)

  • Park, Jungmin;Ahn, Hyunnie
    • Korean Journal of Culture and Social Issue
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    • v.28 no.4
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    • pp.627-659
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    • 2022
  • This study aimed to translate and validate the Positive and Negative Ex-Relationship Thoughts (PANERT), a scale measuring the positive and negative valence of thoughts about past relationships in early adulthood. For this purpose, PANERT was translated into Korean and the study surveyed on 337 single male and female adults in their 20. Then, the gender difference between major variables was analyzed. After going through item analysis, all twelve original items were used to construct the Korean version of PANERT. The confirmatory factor analysis(CFA) supported the two factors structure of the Korean version of PANERT: positive vs, negative thought content valence. Also, the reliability coefficients of each two factors were all satisfactory. As a result of a correlation analysis, the criterion-related validity of the two sub-factors was good with other related scales(Intrusive rumination scale of K-ERRI, K-DASS-21-D, and K-PANAS-Revised) except for changes of self-perception. Finally, the research model was built to examine the mediating effect of two affect responses(positive and negative) in the relationship between two thought content valences and depression. In this process, the convergence and discriminant validity of the Korean version of PANERT were confirmed and the indirect effect was also confirmed in the structural equation model. In conclusion, the Korean version of PANERT consists of two factors and twelve items in total. Also, it is a reliable and valid tool for measuring the thought content valences in the romantic relationship breakup experience of early adults.

Synoptic Change Characteristics of the East Asia Climate Appeared in Seoul Rainfall and Climatic Index Data (서울지점 강우자료와 기후지표자료에 나타난 동아시아 기후의 종관적 변화특성)

  • Hwang, Seok Hwan;Kim, Joong Hoon;Yoo, Chulsang;Chung, Gunhui
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5B
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    • pp.409-417
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    • 2009
  • In this study it was assessed the accuracy of the Chukwooki rainfall data in Seoul by comparing with tree-ring width index data, sunspot numbers, southern oscillation index (SOI) and global temperature anomaly. And it was investigated the correlations of climatic change and change characteristics in past north-east asia by comparisons of tree-ring width index data in near Korea. The results of this study shows that Chukwooki rainfall data has the strong reliance since the trends and depths of change are very well matched with other comparative data. And with the results by compared with tree-ring width index data in six sites of near Korea, climates of north-east asia are changed with strong correlations as being temporal and spatial and longterm periodic possibility of reproducing are exist on those changes. However characteristics of climate change post 1960 A.D. are investigated as represented differently to past although statistical moving characteristics or changing criterion are within the limitations of reproducing phase in the past since they represent the different trends and irregularity and their frequencies are increase. The results of this study are widely used on long-term forecasting for climate change in north-east asia.

Investigation of thermal hydraulic behavior of the High Temperature Test Facility's lower plenum via large eddy simulation

  • Hyeongi Moon ;Sujong Yoon;Mauricio Tano-Retamale ;Aaron Epiney ;Minseop Song;Jae-Ho Jeong
    • Nuclear Engineering and Technology
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    • v.55 no.10
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    • pp.3874-3897
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    • 2023
  • A high-fidelity computational fluid dynamics (CFD) analysis was performed using the Large Eddy Simulation (LES) model for the lower plenum of the High-Temperature Test Facility (HTTF), a ¼ scale test facility of the modular high temperature gas-cooled reactor (MHTGR) managed by Oregon State University. In most next-generation nuclear reactors, thermal stress due to thermal striping is one of the risks to be curiously considered. This is also true for HTGRs, especially since the exhaust helium gas temperature is high. In order to evaluate these risks and performance, organizations in the United States led by the OECD NEA are conducting a thermal hydraulic code benchmark for HTGR, and the test facility used for this benchmark is HTTF. HTTF can perform experiments in both normal and accident situations and provide high-quality experimental data. However, it is difficult to provide sufficient data for benchmarking through experiments, and there is a problem with the reliability of CFD analysis results based on Reynolds-averaged Navier-Stokes to analyze thermal hydraulic behavior without verification. To solve this problem, high-fidelity 3-D CFD analysis was performed using the LES model for HTTF. It was also verified that the LES model can properly simulate this jet mixing phenomenon via a unit cell test that provides experimental information. As a result of CFD analysis, the lower the dependency of the sub-grid scale model, the closer to the actual analysis result. In the case of unit cell test CFD analysis and HTTF CFD analysis, the volume-averaged sub-grid scale model dependency was calculated to be 13.0% and 9.16%, respectively. As a result of HTTF analysis, quantitative data of the fluid inside the HTTF lower plenum was provided in this paper. As a result of qualitative analysis, the temperature was highest at the center of the lower plenum, while the temperature fluctuation was highest near the edge of the lower plenum wall. The power spectral density of temperature was analyzed via fast Fourier transform (FFT) for specific points on the center and side of the lower plenum. FFT results did not reveal specific frequency-dominant temperature fluctuations in the center part. It was confirmed that the temperature power spectral density (PSD) at the top increased from the center to the wake. The vortex was visualized using the well-known scalar Q-criterion, and as a result, the closer to the outlet duct, the greater the influence of the mainstream, so that the inflow jet vortex was dissipated and mixed at the top of the lower plenum. Additionally, FFT analysis was performed on the support structure near the corner of the lower plenum with large temperature fluctuations, and as a result, it was confirmed that the temperature fluctuation of the flow did not have a significant effect near the corner wall. In addition, the vortices generated from the lower plenum to the outlet duct were identified in this paper. It is considered that the quantitative and qualitative results presented in this paper will serve as reference data for the benchmark.

Studies on Development of Prediction Model of Landslide Hazard and Its Utilization (산지사면(山地斜面)의 붕괴위험도(崩壞危險度) 예측(豫測)모델의 개발(開發) 및 실용화(實用化) 방안(方案))

  • Ma, Ho-Seop
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.175-190
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    • 1994
  • In order to get fundamental information for prediction of landslide hazard, both forest and site factors affecting slope stability were investigated in many areas of active landslides. Twelve descriptors were identified and quantified to develop the prediction model by multivariate statistical analysis. The main results obtained could be summarized as follows : The main factors influencing a large scale of landslide were shown in order of precipitation, age group of forest trees, altitude, soil texture, slope gradient, position of slope, vegetation, stream order, vertical slope, bed rock, soil depth and aspect. According to partial correlation coefficient, it was shown in order of age group of forest trees, precipitation, soil texture, bed rock, slope gradient, position of slope, altitude, vertical slope, stream order, vegetation, soil depth and aspect. The main factors influencing a landslide occurrence were shown in order of age group of forest trees, altitude, soil texture, slope gradient, precipitation, vertical slope, stream order, bed rock and soil depth. Two prediction models were developed by magnitude and frequency of landslide. Particularly, a prediction method by magnitude of landslide was changed the score for the convenience of use. If the total store of the various factors mark over 9.1636, it is evaluated as a very dangerous area. The mean score of landslide and non-landslide group was 0.1977 and -0.1977, and variance was 0.1100 and 0.1250, respectively. The boundary value between the two groups related to slope stability was -0.02, and its predicted rate of discrimination was 73%. In the score range of the degree of landslide hazard based on the boundary value of discrimination, class A was 0.3132 over, class B was 0.3132 to -0.1050, class C was -0.1050 to -0.4196, class D was -0.4195 below. The rank of landslide hazard could be divided into classes A, B, C and D by the boundary value. In the number of slope, class A was 68, class B was 115, class C was 65, and class D was 52. The rate of landslide occurrence in class A and class B was shown at the hige prediction of 83%. Therefore, dangerous areas selected by the prediction method of landslide could be mapped for land-use planning and criterion of disaster district. And also, it could be applied to an administration index for disaster prevention.

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