• 제목/요약/키워드: Model Validity

검색결과 4,325건 처리시간 0.049초

3차원 격자요소를 활용한 콘크리트 구조부재의 스트럿-타이 모델 설계 방법 - (II) 타당성 평가 (Strut-Tie Model Approach Associated with 3-Dimensional Grid Elements for Design of Structural Concrete - (II) Validity Evaluation)

  • 김병헌;윤영묵
    • 대한토목학회논문집
    • /
    • 제34권2호
    • /
    • pp.437-446
    • /
    • 2014
  • 현 논문에서는 전편 논문에서 제안한 3차원 격자요소를 활용하는 스트럿-타이 모델 방법의 타당성 및 효율성을 검증하기 위해 파괴실험이 수행된 13개의 슬래브-기둥 접합부 및 51개의 비틀림 보 등의 극한강도를 평가하였으며, 또한 3축 방향의 하중을 받는 교각코핑부에 대한 설계를 수행하였다. 현 연구의 방법에 의한 철근콘크리트 슬래브-기둥 접합부 및 비틀림 보의 극한강도 평가결과는 실험결과, ACI 318 설계기준을 비롯한 세계 주요설계기준, 그리고 몇몇 연구자의 방법에 의한 평가결과 등과 비교하여 현 연구방법의 타당성을 검증하였다. 교각코핑부의 설계결과는 ACI 318 설계기준의 단면법 및 AASHTO-LRFD의 스트럿-타이 모델 설계기준에 의한 설계결과와 비교하여 그 결과의 타당성을 검토하였다.

Applying the Health Belief Model to college students' health behavior

  • Kim, Hak-Seon;Ahn, Joo;No, Jae-Kyung
    • Nutrition Research and Practice
    • /
    • 제6권6호
    • /
    • pp.551-558
    • /
    • 2012
  • The purpose of this research was to investigate how university students' nutrition beliefs influence their health behavioral intention. This study used an online survey engine (Qulatrics.com) to collect data from college students. Out of 253 questionnaires collected, 251 questionnaires (99.2%) were used for the statistical analysis. Confirmatory Factor Analysis (CFA) revealed that six dimensions, "Nutrition Confidence," "Susceptibility," "Severity," "Barrier," "Benefit," "Behavioral Intention to Eat Healthy Food," and "Behavioral Intention to do Physical Activity," had construct validity; Cronbach's alpha coefficient and composite reliabilities were tested for item reliability. The results validate that objective nutrition knowledge was a good predictor of college students' nutrition confidence. The results also clearly showed that two direct measures were significant predictors of behavioral intentions as hypothesized. Perceived benefit of eating healthy food and perceived barrier for eat healthy food to had significant effects on Behavioral Intentions and was a valid measurement to use to determine Behavioral Intentions. These findings can enhance the extant literature on the universal applicability of the model and serve as useful references for further investigations of the validity of the model within other health care or foodservice settings and for other health behavioral categories.

Stochastic Morphological Sampling Theorem을 이용한 지능형 진화형 수신기 구현 (A Design of Intelligent and Evolving Receiver Based on Stochastic Morphological Sampling Theorem)

  • 박재현;이경록송문호김운경
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 하계종합학술대회논문집
    • /
    • pp.46-49
    • /
    • 1998
  • In this paper, we introduce the notion of intelligent communication by introducing a novel intelligent receiver model. This receiver is continually evolving and learns and improves in performance as it compiles its experience over time. In digital communication context, in a typical training mode, it jearns the concept of "1" as is deteriorated by arbitrary (not necessarily additive as is typically assumed) disturbance and /or modulation. After learning "1", in test mode, it classifies the received signal "1" and "0" almost completely. The intelligent receiver as implemented is grounded on the recently introduced Stochastic Morphological Sampling Theorem(SMST), a distribution-free result which gives theoretical bounds on the sample complexity(training size) needed for the required performance parameters such as accuracy($\varepsilon$) and confidence($\delta$). Based on this theorem, we demonstrate --almost irrespective of channel and modulation model-- the number of samples needed to learn the concept of "1" is not too "large" and the resulting universal receiver structure, that corresponding to classical Nearest Neighbor rule in Pattern Recognition Theory, is trivial. We check the surprising efficiency and validity of this model through some simple simulations. and validity of this model through some simple simulations.

  • PDF

Transtheoretical Model을 적용한 국내 간호연구 분석 (Analysis of Korean Nursing Studies Applied for the Transtheoretical Model)

  • 이은현;김진선;정영해
    • 성인간호학회지
    • /
    • 제19권4호
    • /
    • pp.567-582
    • /
    • 2007
  • Purpose: The purpose of this study was to explore the utilization of the Transtheoretical Model(TTM) for Korean nursing studies on health behaviors and identify the strategies for improvement of further studies. Methods: From a main and seven branch journals on the Korean Society of Nursing Science, a total of 26 studies, which had been conducted based upon the TTM, were selected. The selected studies were analyzed from the September of 2006 to the February of 2007 by the criteria; name of journal, year of publication, health behavior, population, sampling, sample size, research design, instrument (translation process, reliability and validity), and statistical analysis. Results: TTM on the Korean nursing studies was mainly applied for smoking cessation or exercise with elderly or middle aged women. The research findings could not be generalized with the limitation of the use of non representative samples. The most frequently used research design was a cross-sectional survey. Some studies had a lack of reliable and valid instruments, so that the internal validity of the study findings may be threatened. Statistically related problems increased type I error and decreased power. Conclusion: Korean nursing studies based on TTM can be the beginning stage in quality and quantity.

  • PDF

구강 내 스캐닝 방법에 의해 제작된 폴리우레탄 모형의 정확도 평가 (Evaluation of validity of polyurethane model fabricated by intra-oral scanning method)

  • 김원태;이병기;현종구;김기백
    • 대한치과기공학회지
    • /
    • 제36권2호
    • /
    • pp.91-96
    • /
    • 2014
  • Purpose: The purpose of this study was evaluate the validity of polyurethane model fabricated by intra oral scanning method. Methods: Ten sam cases of stone models were manufactured from master model, and polyurethane models were made with the intra oral scanning and CNC milling method. One examiner individually measured 6 distances(intercanine distance, intermolar distance, two dental arch lengths(right, left) and two diagonal of dental arch lengths(right, left) on the stone models and the polyurethane models. The Mann-Whitney U test(${\alpha}$=0.05) were used for statistical analysis. Results: The mean difference between measurements made directly on the stone models and those made on the polyurethane models was 0.31-0.38mm. No statistically differences between the two groups were founded 4 distances(p>0.05), but 2 distances were statistically significant(p<0.05). Conclusion: Stone models showed larger than polyurethane models fabricated by intra oral scanning method.

상호작용성 구성요인이 e-learning 사이트 수용의도에 미치는 영향 (The Impact of Interactivity on user Acceptance of e-learning Site)

  • 구자철;신병호;서영호;이상철
    • 경영과학
    • /
    • 제26권2호
    • /
    • pp.71-89
    • /
    • 2009
  • The purpose of this research is to identify the factors affecting user acceptance of e-learning site. To more precisely explain an individual's behavior of accepting e-learning site, Perceived Interactivity is divided into four components; User Control, Responsiveness, Personalization and Connectedness. This research investigates the causal relationship among four components and basic factors of TAM. This research uses structural equation modeling (SEM) to confirm the validity and analyzes the causal relationship of the suggested model. The results indicates strong support for the validity of proposed model with 54.8% of the variance in behavioral intention to e-learning site. The result finds that all the basic casuality of TAM are significant and most components of Perceived Interactivity are significant. However the path Connectedness to Perceived Ease of Use and User Control to Perceived Playfulness is not significant. Among components of Perceived Interactivity, Personalization is the strongest antecedent of TAM. Perceived Usefulness is the strongest antecedent of behavioral intention of e-learning site.

학령기 아동을 위한 활동 참여 평가도구(Activity Participation Assessment)의 타당도 연구 (The Validity of Activity Participation Assessment for School-Age Children)

  • 김세연
    • 대한감각통합치료학회지
    • /
    • 제17권1호
    • /
    • pp.19-29
    • /
    • 2019
  • 목적 : 본 연구의 목적은 학령기 아동을 위한 활동 참여 평가도구(Activity Participation Assessment; APA)의 타당도를 알아보는 것이다. 연구방법 : 초등학생 207명을 대상으로 APA 30문항, PACS(Pediatric Activity Card Sort) 75문항, CAPE(Children's Assessment of Participation and Enjoyment) 55문항으로 구성된 설문지를 실시하였다. APA의 구인타당도를 알아보기 위해 확인적 요인분석을 실시하였으며, 수렴타당도와 판별타당도는 평균분산추출과 상관계수 제곱값을 통해 검증하였으며, 공인타당도는 APA와 PACS 및 CAPE의 피어슨의 상관계수를 통해 검증하였다. 연구결과 : 구인타당도는 확인적 요인분석 결과 수정된 위계적 2차 모형이 적합한 수준으로 나타났으며(p<.001), 수렴타당도는 모든 하위요인에서 평균분산 추출값이 .50이상으로 나타나 입증되었으며, 판별타당도는 평균분산 추출값이 결정계수인 0.239보다 더 크게 나타나 입증되었다. 공인타당도 분석에서 APA 항목 전체와 PACS의 자기관리는 .494(p<.01), 학교/생산성 .575(p<.01), 취미/사회 활동 .647(p<.01), 스포츠 .303(p<.01)으로 모두 정적 상관이 있는 것으로 나타났다. 또한 APA 항목 전체와 CAPE의 여가활동은 .490(p<.01), 신체적 활동 .329(p<.01), 사회 활동 .571(p<.01), 기술에 기초한 활동 .401(p<.01), 자기계발 활동 .390(p<.01)으로 모두 정적 상관관계를 보였다. 결론 : APA는 구인타당도, 수렴타당도, 변별타당도와 공인타당도가 입증되어 국내 학령기 아동의 활동 참여를 측정하는 검사로써 타당한 도구로 사용될 수 있다.

인간신뢰도 학습현상 (Human reliability growth in the absolute identification of tones)

  • 박희석;박경수
    • 대한인간공학회지
    • /
    • 제5권2호
    • /
    • pp.11-15
    • /
    • 1986
  • In this paper, we consider the validity of a human probabilistic learning model applied to the perdiction of errors associated with the absolute identification of tones. It is shown that the probabilistic learning model describes the human error process adequately. The model parameters are estimated by two methods which are the method of maximum likelihood, and the method of mement. The MLE version of the model has the better predictive power but the ME version is more readily obtainable and may be more practical.

  • PDF

Frequency Weighted Model Reduction Using Structurally Balanced Realization

  • Oh, Do-Chang;Kim, Jong-Hae
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2003년도 ICCAS
    • /
    • pp.366-370
    • /
    • 2003
  • This paper is on weighted model reduction using structurally balanced truncation. For a given weighted(single or double-sided) transfer function, a state space realization with the linear fractional transformation form is obtained. Then we prove that two block diagonal LMI(linear matrix inequality) solutions always exist, and it is possible to get a reduced order model with guaranteed stability and a priori error bound. Finally, two examples are used to show the validity of proposed weighted reduction method, and the method is compared with other existing methods.

  • PDF

화력발전소 보일러 급수제어 계통의 모델링과 L.Q. 제어기 적용에 관한 연구 (A Study of Thermal Power Plant Feedwater System with Modeling and L.Q.Controller)

  • 서진헌;황재호
    • 대한전기학회논문지
    • /
    • 제39권12호
    • /
    • pp.1281-1287
    • /
    • 1990
  • A new thermal power plant feed-water system model, which is based on Astrom, is presented. Astrom's model has some difficulties in applying to practical systems because it is not able to measure the heat and energy transfer loss. Hence, in order to make up for these difficulties, the Gas State Equation is added to the model. Computer simulations are performed to show the validity of the new model at thermal power plant with practical boiler operating data and to verify the L.Q. controller effect on boiler drum level system.