• Title/Summary/Keyword: consistency tests

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A Study on the Improvement Effects of Soft Ground through In-Situ Construction of NDS (NDS공법의 현장시험시공을 통한 지반개량 효과에 관한 연구)

  • Ahn, Joon-Hee;Park, Choon-Sik;Jang, Jeong-Wook;Kang, Hyoung-Nam;Kim, Yong-Sik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.653-657
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    • 2005
  • This study applied the NDS method to the creek levee and the foundation of a building, for the purpose of ground improvement and cut-off. The conclusions are shown in the following. (1) The results of the field tests in the creek levee are as follows; the N value of the standard penetration test is $2{\sim}3$ before NDS grout and $9{\sim}21$ after NDS grout; in the alluvial layer, $7{\sim}11$ before NDS grout and $14{\sim}23$ after NDS grout. This confirms increasing ground strength with consistency ranging from stiff to very stiff. (2) The result of the permeability test in the creek levee shows that the ground had a great hydraulic conductivity with complete leakage before ground improvement but that the hydraulic conductivity has significantly increased to $3.17{\times}10^{-5}{\sim}4.65{\times}10^{-5}cm/sec$ after ground improvement by the NDS method. (3) The result from the field test of the foundation of the building confirms great reinforcing effects, showing that the allowable bearing capacity has increased from Pa = 5.0 $t/m^2$ before reinforcement to Pa = 25.0 $t/m^2$ after reinforcement.

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Evaluation on the Applicability of Recycled Fine Aggregate to Precast Concrete Products (순환잔골재의 콘크리트 2차 제품 활용성 평가)

  • Kim, Sang-Chel;Park, Do-Kuk;Yoog, Keun-Chang
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.1
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    • pp.1-9
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    • 2016
  • While the amount of construction waste has not been changed much in discharge for last 10 years, the recycled resources refined from construction waste have been mainly applied to low-leveled one such as reclamation, back-fill, road base or subbase and so on. Thus this study addresses the applicability of recycled fine aggregate as a replaceable material in precast concrete. To evaluate the possibility, both of dry and wet processes were adopted as well as steam curing, widely used in the field for rapid producing. Most important experimental parameters were driven through preliminary experiments and were evaluated in terms of concrete properties. It is found from aggregate-replacement tests that all of consistency and strengths of concrete were decreased as the ratio of recycled fine aggregate increased, and the amount of decrease can be estimated using proposed equations. Though the recycled fine aggregate showed a decrease of concrete properties more or less, the applicability in large volume as a constituent of precast product was well noted from experimental results.

The Development of Infants and Toddlers: A Rating Scale for Teachers (교사 평정용 영아발달 평가도구)

  • Lee, Young Ja;Lee, Jong Sook;Shin, Eun Soo;Kwak, Hyang Lim;Lee, Jeong Wuk
    • Korean Journal of Child Studies
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    • v.22 no.2
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    • pp.255-275
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    • 2001
  • The purpose of this study was to construct a rating scale of infant and toddler development for the use of teachers in their observations of children during daily activities. The scale consists of 201 items measuring motor, self-help, socio-communicative, socio-emotional, and cognitive development. Quality, reliability and validity were examined with the use of a nation-wide sample of 1,245 children from classes of 1- and 2-year-olds. Tests on validity and reliability were high in terms of content validity evaluated by early childhood professionals, concurrent validity with the Bayley Scale, internal consistency among raters, and test-retest reliability. Factor analysis showed that the developmental areas of infants and toddlers are not clearly differentiated but are interrelated with each other. The scale was standardized by providing nation-wide norms with raw scores, percentiles, and standardized scores.

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Development and a Psychometric Evaluation of Cardiovascular Disease-Specific Quality of Life Scale for Koreans (한국 심혈관질환 특이형 삶의 질 측정도구 개발 및 평가)

  • Lee, Eun-Hyun;Tahk, Seong-Jai;Shin, Jun-Han;Lee, Young-Whee;Song, Rha-Yun
    • Journal of Korean Academy of Nursing
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    • v.37 no.3
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    • pp.313-323
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    • 2007
  • Purpose: Health-related quality of life (HRQOL) in patients with cardiovascular disease in Korea has rarely been studied, mostly due to the lack of a psychometrically validated disease-specific instrument. The purpose of this study was to develop and validate a cardiovascular specific-HRQOL questionnaire (CD-QOL). Method: The CD-QOL was developed and validated as follows; item generation, pilot study, and psychometric tests. Patients were recruited from three-university hospitals. The patients were asked to complete the preliminary questionnaire comprising the content-validated items, SF-36, and CES-D. The NYHA and KASI classifications were used to classify the functional performance of the patients. The data was analyzed using correlation, factor analysis, multidimensional scaling, multitrait/multi-item matrix, ANOVA, and Cronbach's alpha. Result: Preliminarily, thirty-nine items were generated. Factor analysisextracted a five-factor solution with a total of twenty-two items. One item was deleted based upon the MDS. The remaining items were moderately correlated with the subscales of the SF-36 and associated with depression measured with the CES-D. The mean scores of patients in NYHA and KASI class I were significantly higher than those in NYHA and KASI class II or/and III, which suggested patients with better functional performance were likely to have a better HRQOL. Cronbach's alphas of the total and subscales were all greater than 0.70. Conclusion: The CD-QOL is a easily applicable instrument with excellent psychometric properties of content, criterion, factorial, convergent, and known-groups validity, and internal consistency reliability in Korean patients with cardiovascular disease.

A Survey on Stress and Coping Style in Mothers of Cerebral Palsied Children (뇌성마비아동 어머니의 스트레스 및 대처방식 조사)

  • Lee, Hye-Young;Kim, Kyoung;Cha, Yong-Jun
    • The Journal of Korean Physical Therapy
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    • v.24 no.2
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    • pp.98-106
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    • 2012
  • Purpose: The goal of this study was to analyze the degree of stress and methods of coping with stress in mothers of cerebral palsied children and to provide a basic resource for the development of policies to improve the mental health of mothers with cerebral palsied children. Methods: 85 mothers with cerebral palsied children and 77 mothers of normal children completed a self-administered questionnaire that evaluated the degree of stress and methods of coping with stress. Cronbach's ${\alpha}$ score was used to determine the internal consistency of the acquired data and the discriminated validity was estimated by Pearson's correlation coefficient. Independent t-tests were conducted to compare the degree of stress and method of coping with stress between mothers of cerebral palsied children and mothers of normal children and one-way ANOVA was performed to analyze the effect of generalized characteristics on stress in mothers of cerebral palsied children. Results: The degree of stress in terms of anxiety response and roles as mother for mothers with cerebral palsied children was higher than mothers with normal children. However, there was no significant difference between two group in regards to the methods of coping with stress during a stressful episode. The degree of stress for mothers with cerebral palsied children was greater when the child was younger. Conclusion: Mothers of cerebral palsied children had higher stress than that of mothers with normal children and felt more stress when their child was younger. Therefore, these results suggest that health-based policies should be developed to improve the mental health of mothers with cerebral palsied children.

Implicit Validation of the Concept of Successful Aging for Korean Elderly (한국 노인의 성공적 노후 개념에 대한 암시적 타당화)

  • Joo, Min-Kyoung;Song, Sun-Hee
    • The Journal of the Korea Contents Association
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    • v.12 no.2
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    • pp.505-516
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    • 2012
  • The purpose of the this research is to find out what basic factors of aging for korean elderly(above 65years old). First of all, 90 preliminary questions were developed from 551 questionnaires. In addition, some practices of the composition factors were carried out from another 552 seniors and additional tests were tried for composition validity, certified validity and successful aging standards from other 399 elders. The survey showed that the standard of the successful aging for korean elderly, which was composed of 47 questions, displayed satisfaction of everyday life, off-spring's success, psychological support, positive activity. sense of self effectiveness, mental stability, satisfaction of spousal relationship and family support. The reliability of the Validation of Successful Aging for Korean Elderly showed high internal consistency of 0.932. It is also verified that the relationship between the factors and the questions has statistically meaningful, which makes it possible to confirm the reliability of the structure of the factors.

Effects of Consumer's Characteristics on Trust and Purchase Intention of On-line Shopping Mall -Focusing on Chinese Users of Internet Shopping Mall- (소비자 특성이 온라인 쇼핑몰에 대한 신뢰와 구매의도에 미치는 영향 -중국 인터넷쇼핑몰 사용자를 중심으로-)

  • Park, Hea-Ryung
    • Fashion & Textile Research Journal
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    • v.7 no.5
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    • pp.501-508
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    • 2005
  • The purpose of this study was to investigate the effects of Chinese consumer characteristics as internal inclination on the trust and purchase intention of on-line shopping mall. Two hundred sixty subjects, who were living in Shanghai, China and were university students, were randomly selected for questionnaire. The effective two hundred forty four questionnaires were used to conduct reliability tests for internal consistency and multiple regressions for relationship between independent and dependent variables with SPSS 10.0. The results from this study were as follows. It showed a significant relationship between the on-line shopping experience, consumer innovation, consumer risk and the trust of on-line shopping mall, however, it didn't show any significant relationship between convenience shopping orientation and the trust of on-line shopping mall. Also, It showed a significant relationship between the on-line shopping experience, consumer innovation and the distrust of on-line shopping mall, however, it didn't show any significant relationship between consumer risk, convenience shopping orientation and the distrust of on-line shopping mall. It showed a significant relationship between purchase intension, the consumer risk and on-line shopping experience which appeared a high trust in on-line shopping mall, however, it didn't show any significant relationship between purchase intension and consumer innovation which appeared a high distrust. Therefore, it could be concluded that in China it is decreasing to purchase through the internet shopping mall every year because the group of consumer innovation, which most of internet users in China belong to it, distrusts the internet shopping mall.

Assessing Korean Middle School Students' Spatial Ability: Comparison between Gifted Students and General Students (한국의 중학교 영재학생과 일반학생의 공간 능력의 차이에 관한 연구)

  • Park, Sung-Sun
    • Journal of Gifted/Talented Education
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    • v.22 no.2
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    • pp.371-386
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    • 2012
  • Spatial ability has been valued as one component of intelligence and as an talented domain. The researchers agree that spatial ability is associated with the achievements in science, technology, engineering, and mathematics (STEM) disciplines and important in STEM education. The purpose of this study is to assess Korean middle school students' spatial ability and compare Gifted Students and General Students' spatial ability. For this purpose, 'The Revised PSVT:R' was translated into Korean and administered 509 Korean middle school students, and also internal consistency reliability evidence and construct validity evidence of 'The Revised PSVT:R' were examined. This study explored the spatial ability of Korean middle school students (graded 7 through 9), and investigated association between spatial ability and students' mathematics achievement, the students' spatial ability according to their gender and grade level. As a result, this study shows that gifted students were better than general students in spatial ability. And there were significant correlations between spatial ability and mathematics, science, Korean language achievement. According to these results, spatial ability should be included as one of the important components in identifying students for gifted education programs.

Protective Effects of Green Tea Polyphenol Against Renal Injury Through ROS-Mediated JNK-MAPK Pathway in Lead Exposed Rats

  • Wang, Haidong;Li, Deyuan;Hu, Zhongze;Zhao, Siming;Zheng, Zhejun;Li, Wei
    • Molecules and Cells
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    • v.39 no.6
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    • pp.508-513
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    • 2016
  • To investigate the potential therapeutic effects of polyphenols in treating Pb induced renal dysfunction and intoxication and to explore the detailed underlying mechanisms. Wistar rats were divided into four groups: control groups (CT), Pb exposure groups (Pb), Pb plus Polyphenols groups (Pb+PP) and Polyphenols groups (PP). Animals were kept for 60 days and sacrificed for tests of urea, serum blood urea nitrogen (BUN) and creatinine. Histological evaluations were then performed. In vitro studies were performed using primary kidney mesangial cells to reveal detailed mechanisms. Cell counting kit-8 (CCK-8) was used to evaluate cell viability. Pb induced cell apoptosis was measured by flow cytometry. Reactive oxygen species (ROS) generation and scavenging were tested by DCFH-DA. Expression level of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-1-${\beta}$ (IL-1-${\beta}$) and IL-6 were assayed by ELISA. Western blot and qPCR were used to measure the expression of ERK1/2, JNK1/2 and p38. Polyphenols have obvious protective effects on Pb induced renal dysfunction and intoxication both in vivo and in vitro. Polyphenols reduced Pb concentration and accumulation in kidney. Polyphenols also protected kidney mesangial cells from Pb induced apoptosis. Polyphenols scavenged Pb induced ROS generation and suppressed ROS-mediated ERK/JNK/p38 pathway. Downstream pro-inflammatory cytokines were inhibited in consistency. Polyphenol is protective in Pb induced renal intoxication and inflammatory responses. The underlying mechanisms lie on the antioxidant activity and ROS scavenging activity of polyphenols.

Statistical procedures of add-on trials for bioequivalence in 2×k crossover designs (2×k 교차설계법에서 생물학적 동등성 추가시험의 통계적 절차)

  • Woo, Hwahyoung;Park, Sang-Gue
    • Journal of the Korean Data and Information Science Society
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    • v.25 no.6
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    • pp.1181-1193
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    • 2014
  • Currently Ministry of food and drug safety allows add-on trial when the bioequivalence between two drugs fails to show since July 1, 2008. However, bioequivalence of highly variable drugs based on $2{\times}2$ crossover designs would require too many subjects, so the alternative designs like $2{\times}4$ or $2{\times}3$ crossover experiments are preferred. In this paper, we propose and discuss the statistical procedures for add-on trials in $2{\times}4$ and $2{\times}3$ crossover designs.