• Title/Summary/Keyword: proportions test

Search Result 345, Processing Time 0.033 seconds

A Review of Media Argumentation: Roles of Background Knowledge in Critical Reading

  • Lee, Jong-Hee
    • English Language & Literature Teaching
    • /
    • v.15 no.4
    • /
    • pp.157-175
    • /
    • 2009
  • This paper offers a critical review of a newspaper argument regarding the problems of high school education assessment for university entrance examination system in the United Kingdom. The media account raises three sets of questioning to hold that the nation's long-standing A-levels have failed and is no longer viable as a high-stakes test. However, it is found that the writer's argumentations involving misleading conceptions can be deconstructed because of invalid reasoning and unreliable evidence. So, it is proposed that a reasonable solution to replace the discredited A-level exams should be to adopt an eclectic approach for assessing candidates' multiple capabilities; performance, potentiality and critical thinking skills. These criteria for component-oriented assessments are designed to measure their high school academic achievements and intellectual capacity for tertiary education; in the process of such measurement, critical-logical reasoning abilities for sound judgment and problem-solving tasks should be incorporated with the basic precondition that each university possesses its own discretion for the determination of adequate proportions to reflect each of the assessment outcomes. It is, therefore, expected that this critical review will inspire the readers to understand aspects of assessment as an educational field and to confirm how seriously they may be misguided by a distorted media argumentation without substantive background knowledge.

  • PDF

A predictive model for compressive strength of waste LCD glass concrete by nonlinear-multivariate regression

  • Wang, C.C.;Chen, T.T.;Wang, H.Y.;Huang, Chi
    • Computers and Concrete
    • /
    • v.13 no.4
    • /
    • pp.531-545
    • /
    • 2014
  • The purpose of this paper is to develop a prediction model for the compressive strength of waste LCD glass applied in concrete by analyzing a series of laboratory test results, which were obtained in our previous study. The hyperbolic function was used to perform the nonlinear-multivariate regression analysis of the compressive strength prediction model with the following parameters: water-binder ratio w/b, curing age t, and waste glass content G. According to the relative regression analysis, the compressive strength prediction model is developed. The calculated results are in accord with the laboratory measured data, which are the concrete compressive strengths of different mix proportions. In addition, a coefficient of determination $R^2$ value between 0.93 and 0.96 and a mean absolute percentage error MAPE between 5.4% and 8.4% were obtained by regression analysis using the predicted compressive analysis value, and the test results are also excellent. Therefore, the predicted results for compressive strength are highly accurate for waste LCD glass applied in concrete. Additionally, this predicted model exhibits a good predictive capacity when employed to calculate the compressive strength of washed glass sand concrete.

Performance Evaluation of Carbon-Reducing Soil Pavement using Inorganic Binder (무기계 바인더를 이용한 탄소저감형 흙포장의 성능평가)

  • Yoo, Ji Hyeung;Kawk, Gi Bong;Kim, Dae Sung
    • International Journal of Highway Engineering
    • /
    • v.17 no.6
    • /
    • pp.19-26
    • /
    • 2015
  • PURPOSES : This study intends to develop an inorganic soil pavement material using industrial by-products and to evaluate its applicability as a road pavement material. METHODS : In this study, a compressive strength experiment was conducted based on the NaOH solution molarity and water glass content to understand the strength properties of the soil pavement material according to the mixing ratio of alkali activator. In addition, the strength characteristic of the inorganic soil pavement material was analyzed based on the binder content. The performance of the soil pavement was evaluated by conducing an accelerated pavement test and a falling weight deflectometer (FWD) test. RESULTS : As a result of the soil pavement material test based on the mixture ratio of alkali activator, it was identified that the activator that mixed a 10 M NaOH solution to water glass in a 5:5 ratio is appropriate. As a result of the inorganic soil pavement materials test based on the binder content, the strength development increased sharply when the amount of added binder was over 300 kg; this level of binder content satisfied 28 days of 18 MPa of compression strength, which is the standard for existing soil pavement design. According to the measured results of the FWD test, the dynamic k-value did not show a significant difference before or after the accelerated pavement testing. Furthermore, the effective modulus decreased by approximately 50%, compared with the initial effective modulus for pedestrian pavement. CONCLUSIONS : Based on these results, inorganic soil pavement can be applied by changing the mixture proportions according to the use of the pavement, and can be utilized as road pavement from light load roads to access roads.

Factors Associated with Indeterminate and False Negative Results of QuantiFERON-TB Gold In-Tube Test in Active Tuberculosis

  • Cho, Ki-Won;Cho, Eun-Ha;Kwon, Soo-Hoon;Im, Sang-Hyuk;Sohn, In;Song, Sook-Hee;Kim, Hye-Ok;Kim, Su-Hyun
    • Tuberculosis and Respiratory Diseases
    • /
    • v.72 no.5
    • /
    • pp.416-425
    • /
    • 2012
  • Background: The sensitivities and specificities of interferon-gamma release assays (IGRAs) vary among different population studies, and the data on the routine use of IGRAs are limited. The aim of this study was to evaluate the role of QuantiFERON-TB Gold In-Tube (QFT-GIT) test in the diagnosis of active tuberculosis. Methods: We conducted a prospective study, enrolling 77 patients with suspected pulmonary tuberculosis (TB), at a secondary care teaching hospital in Seoul. Results: In total, 12 (15.6%) patients showed indeterminate results due to positive control failure on the QFT-GIT test. Indeterminate results were significantly associated with the elderly, history of the intensive care unit stay, lymphocytopenia, especially low CD4 count, increased C-reactive protein and decreased protein levels. Of the 77 patients, 44 (57.1%) were diagnosed with active pulmonary tuberculosis, and the percentage of false negative results of the QFT-GIT was 36.4% (vs. 31.8% with TST). In the TB group with >65 years old (n=12), the proportions of the indeterminate (33.3% vs. 3.1%) and the false negative results (58.3% vs. 25.0%) of the QFT-GIT were significantly higher than in the younger TB group (n=32). Conclusion: Indeterminate and false negative results of QFT-GIT test were not infrequent in tuberculosis, especially in the elderly. Care should be considered for the interpretation with the elderly, immunocompromised, chronic and severely diseased patients.

Relationships Between Edge Formation of Burned Forests and Landscape Characteristics with Consideration on Spatial Autocorrelation (공간 자기상관성을 고려한 산불피해지 경계 형성과 경관특성변수들과의 관계)

  • Lee, Sang-Woo;Won, Myoung-Soo;Lee, Hyun-Joo
    • Journal of Korean Society of Forest Science
    • /
    • v.102 no.1
    • /
    • pp.113-121
    • /
    • 2013
  • It has been known that edges of forest fire areas play significant roles in post-fire change of forest ecosystem and recovery process. The purpose of this study was to analyze the relationships between edge formation of burned forests and landscape characteristics with consideration on spatial autocorrelation. Samcheok fire site burned in 2000 was selected as the study area. Seven hundred fifty three of 500 $m^2$ grid cells were generated for measuring landscape characteristics. This study used the topographic variables including slop, elevation, topographic wetness index, solar radiation index and proportions of fuel and land use types. In delineating landscape characteristics correlation analysis with modified t-test were performed for exploring the relationships between edge formation and landscape characteristics. The results indicated that edge formation of burned forests was positively correlated with most variables including TWI, SRI, water, paddy, developed, farm, grass, bare soil, and negatively related with elevation, slope and all fuel types. Especially TWI (r=0.437) showed a strong positive correlation with edge formation. According to the results, edge of burned forests were likely formed when proportions of heterogeneous land use types were high with mild slope and low elevation.

Comparing validity of using Body Mass Index, Waist to Hip Ratio, and Waist Circumference to Cardiovascular Risk Factors of Middle Aged Koreans (한국중년층에서 체질량지수, 허리-엉덩이둘레비, 및 허리둘레의 심장혈관계질환 위험인자 타당도 비교)

  • Mun, Hyeon-Gyeong;Kim, Yu-Jin
    • Journal of the Korean Dietetic Association
    • /
    • v.11 no.3
    • /
    • pp.365-374
    • /
    • 2005
  • This study was conducted to compare the validity of obese index among body mass index(BMI), waist to hip ratio(WHR), and waist circumference(WC) and to determine which is the best in relation to cardiovascular risk factors of middle aged Korean(40-64yr).Data from the 1998 Korean Health and Nutrition Survey were used(N=3380). Anthropometric indices and cardiovascular risk factors were measured. Chi-square test, analysis of variance following duncan's multiple range test, partial correlation analysis, and Receiver Operator characteristic(ROC) curves were used in the analysis. There was a significant increasing trend in WHR, systolic blood pressure(SBP), high density lipoprotein cholesterol(HDL), and fasting blood sugar(FBS) with age categories of male and in BMI, WC, WHR, diastolic blood pressure(DBP), SBP, total cholesterol(TC), low density lipoprotein cholesterol(LDL), triglycerol(TG), and FBS with those of female. Specially female had the characteristics of upper body fat and systolic blood pressure risk(p<0.05). Proportions of subjects with lifestyle factors related to cardiovascular risk in overweight or upper body fat group were higher than that of normal group. Higher proportions of subjects were practiced exercise in upper body fat group of male than in other groups. Among 7 cardiovascular risk factors in partial correlation analysis, BMI had the highest correlation coefficient in 6 risk factors in male, whereas WC in 4 risk factors in female. Mean of each obese index according to cardiovascular risk groups except smoker was higher than that of normal(p<0.05). These trends were shown in upper body fat group and female. In ROC analysis of 12 risk factors and health conditions, the largest area under curve among obese indices for risk factors were BMI in male and WHR in female. The optimal cutoff values of each index(BMI: WHR: WC) for one or more cardiovascular risk factors were 23.13: 0.89: 85.35 in male and 23.57: 0.84: 78.35 in female. The results showed that cardiovascular risk factors were prevalent in middle aged Koreans within normal limits of obese indices like another Asians. For the identification of cardiovascular risk factors of middle aged Koreans, BMI for men and WHR for women are appropriate indices. But it is recommended that BMI, WHR, and WC, all three indices should be considered, when using these indices.

  • PDF

A Study on the Heat Resistance of Light-Weight Polymer Concrete Composites (경량 폴리머 콘크리트 복합체의 내열성능에 관한 연구)

  • Jo, Young-Kug
    • Journal of the Korea Institute of Building Construction
    • /
    • v.8 no.6
    • /
    • pp.131-137
    • /
    • 2008
  • In recent years, the light-weight aggregate has widely been used to reduce the weight of construction structures, and to achieve the thermal insulation of building structures. The purpose of this study is to evaluate the heat resistance of polymer concrete composites with light-weight aggregate made by binders as resin and cement with polymer dispersion. The light-weight polymer concrete composites are prepared with various conditions such as binder content, filler content, void-filling ratio, light-weight aggregate content and polymer-cement ratio, and tested for heat resistant test, and measured the weight reducing ratio, strengths and exhaustion content of gas such as CO, NO and $SO_2$. From the test results, the weight reducing ratio of light weight polymer concrete using UP binder after heat resistance test increase with an increase in the UP content irrespective of the filler content. The weight reducing ratio of polymer cement concrete is considerably smaller than that of UP concrete. In general, the strengths after heat resistance of polymer concrete composites are reduced about 40 to 65% compared with those before test. The exhausted quantity of CO, NO and $SO_2$ gases in polymer concrete composites is less than EPS(Expanded poly styrene). From the this study, it is confirmed that the many types gases discharge according to binder type of polymer concrete composites, its amount is controlled by selection of the binder type and mix proportions.

Determinants of Potentially Unnecessary Cervical Cancer Screenings in American Women

  • Seo, Munseok;Langabeer, James
    • Journal of Preventive Medicine and Public Health
    • /
    • v.51 no.4
    • /
    • pp.181-187
    • /
    • 2018
  • Objectives: To identify factors responsible for potentially clinically unnecessary cervical cancer screenings in women with prior hysterectomy. Methods: A retrospective cross-sectional study was conducted using the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System (BRFSS). This study targeted adult women and examined whether they received a both a Papanicolaou (Pap) test and undergone a hysterectomy in the last three years. We conducted multivariate analyses, including weighted proportions and odds ratios (ORs), based on the modified BRFSS weighting method (raking). The inclusion criteria were adult women (>18 years old) who reported having received a Pap test within the last 3 years. Results: Of all women (n=252 391), 72 366 had received a Pap test, and 32 935 of those women (45%, or 12.5 million, weighted) had a prior hysterectomy. We found that age, race/ethnicity, marital status, family income, health status, time since last routine checkup, and health insurance coverage were all significant predictors. Black, non-Hispanic women were 2.23 times more likely to receive Pap testing after a hysterectomy than white women (OR, 2.23; 95% confidence interval [CI], 1.99 to 2.50). Similarly, the odds for Hispanic women were 2.34 times higher (OR, 2.34; 95% CI, 1.97 to 2.80). The odds were also higher for those who were married (OR, 1.17; 95% CI, 1.08 to 1.27), healthier (OR, 1.24; 95% CI, 1.14 to 1.35), and had health insurance (OR, 1.54; 95% CI, 1.28 to 1.84), after controlling for confounders. Conclusions: We conclude that women may potentially receive Pap tests even if they are not at risk for cervical cancer, and may not be adequately informed about the need for screenings. We recommend strategies to disseminate recommendations and information to patients, their families, and care providers.

Effect of Natural Jute Fiber on Bond between Polyolefin Based Macro Fiber and Cement Matrix (폴리올레핀계 매크로 섬유와 시멘트 경화체의 부착특성에 미치는 천연마섬유의 효과)

  • Lee, Jin-Hyung;Park, Chan-Gi
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.31 no.3A
    • /
    • pp.251-260
    • /
    • 2011
  • In this study, the effect of natural jute fiber volume fraction on the bond characteristics of polyolefin based macro fiber in natural jute fiber reinforced cement composites, including bond strength, interface toughness, and microstructure analysis are presented. The experimental results on polyolefin based macro fiber pullout test of different conditions are reported. Natural jute fiber volume fractions ranging from 0.1% to 0.2% are used in the mix proportions. Pullout tests are conducted to measure the bond characteristics of polyolefin based macro fiber from natural jute fiber reinforced cement composites. Test results are found that the incorporation of natural jute fiber can effectively enhance the polyolefin based macro fiber-cement matrix interfacial properties. The bond strength and interface toughness between polyolefin based macro fiber and natural jute fiber reinforced cement composites increases with the volume fraction of natural jute fiber. The microstructural observation confirms the findings on the interface bond mechanism drawn from the fiber pullout test results.

Validation of fetus aneuploidy in 221 Korean clinical samples using noninvasive chromosome examination: Clinical laboratory improvement amendments-certified noninvasive prenatal test

  • Kim, Min-Jeong;Kwon, Chang Hyuk;Kim, Dong-In;Im, Hee Su;Park, Sungil;Kim, Ji Ho;Bae, Jin-Sik;Lee, Myunghee;Lee, Min Seob
    • Journal of Genetic Medicine
    • /
    • v.12 no.2
    • /
    • pp.79-84
    • /
    • 2015
  • Purpose: We developed and validated a fetal trisomy detection method for use as a noninvasive prenatal test (NIPT) including a Clinical Laboratory Improvement Amendments (CLIA)-certified bioinformatics pipeline on a cloud-based computing system using both Illumina and Life Technology sequencing platforms for 221 Korean clinical samples. We determined the necessary proportions of the fetal fraction in the cell-free DNA (cfDNA) sample for NIPT of trisomies 13, 18, and 21 through a limit of quantification (LOQ) test. Materials and Methods: Next-generation sequencing libraries from 221 clinical samples and three positive controls were generated using Illumina and Life Technology chemistries. Sequencing results were uploaded to a cloud and mapped on the human reference genome (GRCh37/hg19) using bioinformatics tools. Based on Z-scores calculated by normalization of the mapped read counts, final aneuploidy reports were automatically generated for fetal aneuploidy determination. Results: We identified in total 29 aneuploid samples, and additional analytical methods performed to confirm the results showed that one of these was a false-positive. The LOQ test showed that the proportion of fetal fraction in the cfDNA sample would affect the interpretation of the aneuploidy results. Conclusion: Noninvasive chromosome examination (NICE), a CLIA-certified NIPT with a cloud-based bioinformatics platform, showed unambiguous success in fetus aneuploidy detection.