• Title/Summary/Keyword: test theory

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Application and the Effect of Nutrition Education Program Based on the Social Cognitive Theory Among Middle School Girls (일부 여자 중학생 대상 사회인지이론기반 영양교육 프로그램의 적용 및 효과)

  • Kim, Jihea;Woo, Taejung;Lee, Kyoung Ae;Lee, Seung Min;Lee, Kyung-Hea
    • Korean Journal of Community Nutrition
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    • v.21 no.6
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    • pp.497-508
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    • 2016
  • Objectives: The purpose of this study was to evaluate the effect of nutrition education using materials based on social cognitive theory. Education topics focused on improving health-related and dietary self-awareness and behavior capability in adolescents. Methods: Participants were recruited from a middle school for girls; 67 students (educated group, n=34 and control group, n=33) participated. The education group received 12 lessons in club activity class. Self-administered surveys were conducted for each group before and after the nutrition education program. The questionnaires consisted of variables such as self-efficacy, outcome expectation, outcome expectancy, knowledge, and dietary practices based on the social cognitive theory. Education satisfaction was evaluated using a five-point Likert scale for two sections: a) teaching and learning and b) education results. The data were analyzed using a t-test and Chi Square-test (significance level: p < 0.05). Results: In the education group, post-education, there were significant differences in self-efficacy (p < 0.05), knowledge (p < 0.01), and dietary practices (p < 0.05), whereas outcome expectation and expectancy did not show any significant differences. None of the variables showed any significant differences in the control group. Educational satisfaction scores were $4.38{\pm}0.12$ (teaching and learning) and $4.14{\pm}0.15$ (education results). Conclusions: This study showed that improving adolescent's awareness and behavior capability has a positive effect on their dietary practices. Moreover, this study suggested that a theory-based determinant should be considered to improve dietary behavior among adolescents.

A Comparative Study on Formulation of Three-Dimensional Elastic-Plastic Finite Deformation Analysis for Prediction Large Deflection (강부재의 대변형 예측을 위한 3차원 탄소성 유한변위해석의 정식화에 대한 비교연구)

  • Jang, Gab-Chul;Chang, Kyong-Ho
    • Journal of Korean Association for Spatial Structures
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    • v.6 no.4 s.22
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    • pp.53-61
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    • 2006
  • In th is paper, to predicting the large deformation and cyclic plastic behavior of steel members under loading, 3-Dimensional elastic-plastic FE analysis method is developed by using finite deformation theory and proposed cyclic plasticity model. finite deformation theory, described the large deformation, is formulated by using Updated-lagrangian formulation and Green's strain tensor, Jaumann's derivative of Kirchoff stress. Also, cyclic plasticity model proposed by author is applied to developed analysis method. To verification of developed analysis method, analysis result of steel plate specimen compare to the analysis result using infinitesimal deformation theory and test result. Also, load-displacement and deflection shape, analysis result of pipe-section steel column, compare to test result. The good agreement between analysis result and experiment result shown that developed 3-dimensional finite element analysis can be predict the large deformation and cyclic plastic behavior of steel members.

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A Comparison of Scientists' and Students' Responses to Discrepant Event and Alternative Hypothesis in the Conceptual Change Processes from the Phlogiston Theory to the Oxygen Theory (플로지스톤설에서 산소설로의 개념 변화 과정에서 변칙 사례와 대안 가설에 대한 과학자들과 학생들의 반응 비교)

  • Noh, Tae-Hee;Yun, Jeong-Hyun;Kang, Hun-Sik;Kang, Suk-Jin
    • Journal of The Korean Association For Science Education
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    • v.26 no.7
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    • pp.798-804
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    • 2006
  • In this study, we investigated students' responses to a discrepant event and an alternative hypothesis which had been presented in the conceptual change processes from the phlogiston theory to the oxygen theory, and compared them with scientists' responses. The data concerning scientists' responses to the discrepant event and the alternative hypothesis were gathered from the relevant literature on the history of science. Subjects were 148 eighth graders who possessed the target misconception about combustion through a preconception test. After having been presented with the discrepant event and the alternative hypothesis, students were asked to respond to the test of response to discrepant event. Although similar types of responses were obtained from both scientists and students, there was also a clear difference. Scientists tended to focus on explaining the problems of the discrepant event, whereas students tended to ignore and/or exclude the discrepant event in order to maintain their previous beliefs. Only a few students were also found to change their beliefs after having been presented with the alternative hypothesis.

TIME-DEPENDENT FRACTURE OF ARTICULAR CARTILAGE: PART 1 - THEORY & VALIDATION

  • Mun, M.S.;Lewis, J.L.
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.05
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    • pp.27-33
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    • 1995
  • A time-dependent large deformation fracture theory is developed for application to soft biological tissues. The theory uses the quasilinear viscoelastic theory of Fung, and particularizes it to constitutive assumptions on polyvinyl-chloride (PVC) (Part I) and cartilage (Part II). This constitutive theory is used in a general viscoelastic theory by Christensen and Naghdi and an energy balance to develop an expression for the fracture toughness of the materials. Experimental methods are developed for measuring the required constitutive parameters and fracture data for the materials. Elastic stress and reduced relaxation functions were determined using tensile and shear tests at high loading rates with rise times of 25-30 msec, and test times of 150 sec. The developed method was validated, using an engineering material, PVC to separate the error in the testing method from the inherent variation of the biological tissues. It was found that the the proposed constitutive modeling can predict the nonlinear stress-strain and the time-dependent behavior of the material. As an approximation method, a pseudo-elastic theory using the J-integral concept, assuming that the material is a time-independent large deformation elastic material, was also developed and compared with the time-dependent fracture theory. For PVC. the predicted fracture toughness is $1.2{\pm}0.41$ and $1.5{\pm}0.23\;kN/m$ for the time-dependent theory and the pseudo-elastic theory, respectively. The methods should be of value in quantifying fracture properties of soft biological tissues. In Part II, an application of the developed method to a biological soft tissue was made by using bovine humeral articular cartilage.

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Study on Early Adhesive Characteristic of Chip Seals Using a Surface Energy Approach (표면 에너지 원리를 이용한 칩실 포장의 초기 점착력 특성 연구)

  • Im, Jeong Hyuk
    • International Journal of Highway Engineering
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    • v.17 no.6
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    • pp.47-54
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    • 2015
  • PURPOSES : The objective of this study is to evaluate the early adhesive characteristic of asphalt emulsions, including polymer-modified emulsions, for chip seals using the surface energy concept, the bitumen bond strength (BBS) test, and the Vialit test. METHODS : Two general methods, the BBS test and Vialit test, were applied to investigate the bond strength and the aggregate loss, respectively. A new theory, the surface free energy (SFE) theory, was used to evaluate the adhesive characteristic between the emulsion and the aggregate. Based on the theory, the contact angles were measured, and then the surface energy components were calculated. Using those components, the work of adhesion (Wa) was calculated for each emulsion. To ensure reliable results, all the tests were performed under the same conditions, i.e., at $25^{\circ}C$ for 240 minutes of curing time. For the materials, three emulsions (CRS-2, CRS-2L, and CRS-2P) and one aggregate type (granite) were employed. RESULTS AND CONCLUSIONS : Under the same conditions, the modified emulsions showed better adhesive characteristics and curing behaviors than the unmodified emulsions. In addition, there was no significant difference between the various modified emulsions. One of the important findings is that the analysis by Wa presents more sensitive results than other methods. The results of the Wa showed that the CRS-2P emulsion has the best adhesive characteristics. Consequently, the use of modified emulsions for chip seals could prevent aggregate loss and allow open traffic earlier.

Effects of Active Parenting Today based on Goal Attainment Theory on Parenting Stress, Parenting Behavior, and Parenting Satisfaction in Mothers of School-Age Children (목표달성이론에 근거한 적극적 부모역할훈련이 학령기아동 어머니의 양육스트레스, 양육행동, 부모역할만족도에 미치는 효과)

  • Park, Kyung Im;Oh, Sangeun
    • Journal of Korean Academy of Nursing
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    • v.42 no.5
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    • pp.659-670
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    • 2012
  • Purpose: The purpose of this study was to verify effects of the Active Parenting Today (APT) program based on King's Goal Attainment Theory on parenting stress, parenting behavior, and parenting satisfaction in mothers of school-age children. Methods: This was a quasi-experimental study with a non-equivalent control group pre-post test design. Participants were 39 mothers of school-age children (19 in the experiment group and 20 in the control group) who were registered at two community children centers in G city. The experimental group received the APT program (2 hours/session/week) and telephone counseling (2 times/week) for 8 weeks. Data were analyzed using ${\chi}^2$-test, t-test, Fisher exact probability test, and ANCOVA with the SPSS/Win15.0 program. Results: Parenting stress was significantly lower in the experimental group than in the control group. Positive parenting behavior and parenting satisfaction were significantly higher in the experimental group than in the control group. However, negative parenting behavior was not significantly different between the two groups. Conclusion: The results of this study indicate that the APT program based on King's Goal Attainment Theory is useful in reducing parenting stress, creating positive parenting behavior change, and promoting parenting satisfaction in mothers of school-age children.

The Effect of Korean Medical Treatment on Systemic Sclerosis : A Case Report (경피증에 대한 한방치료 효과 : 증례보고)

  • Kim, Myung Kwan;Jeong, Jeong Gyo;Kim, Kyung Min;Kim, Hyun Ji;Kim, Jung Ho;Kim, Young Il;Jeon, Ju Hyun
    • Journal of Acupuncture Research
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    • v.33 no.3
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    • pp.207-218
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    • 2016
  • Objectives : The purpose of this study is to report the clinical effect of Korean Medical Treatment and acupuncture based on M-test theory & herbal medicine for treating systemic sclerosis. Methods : We treated a patient diagnosed with systemic sclerosis. We used general acupuncture & acupuncture based on M-test theory, herbal medicine, moxibustion, and physical therapy. The outcomes were evaluated by using peripheral body temperature measurement, numeric rating scale(NRS), visual analog scale(VAS), and an activities of daily living(ADL) questionnaire for systemic sclerosis. Results : The average peripheral body temperature increased from $36.16^{\circ}C$ to $36.38^{\circ}C$. The NRS showed no difference, but VAS decreased from 7.43 to 5.43. The ADL questionnaire score decreased from 17 to 12. Conclusion : This case study suggests that Korean Medical Treatment and acupuncture based on M-test theory & herbal medicine could be effective for treating systemic sclerosis. However, further studies are needed to confirm this result.

Attributes of Social Networking Services : A Classification and Comparison (소셜 네트워크 서비스의 속성 : 분류와 비교)

  • Sohn, Jeong Woong;Kim, Jin Ki
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.41 no.1
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    • pp.24-38
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    • 2018
  • Since a social networking service (SNS) isconsidered as an effective means to communicate and interact with customers, companies are trying to utilize SNS effectively. There is a lack of theory relating to the attributes of SNS. This study aims to investigate the attributes of SNS to classify SNS. Based on the social network theory, and previous studies on internet, blog, homepage, communication attributes, this study proposes the seven attributes to classify SNS: interaction, communication, entertainment, information, sharing, intimacy and connection. A pre-test, a pilot test and a main test are conducted. In the main test, 239 SNS users are participated. Through a factor analysis this study verifies the seven attributes of SNS. An analysis of variance with multiple comparisons of $Scheff{\acute{e}}$ method identifies that three attributes, interaction, communication and connection, are found to play significant roles to differentiate SNS. Looking at the overall mean values of the SNS by attribute, interaction, sharing, entertainment, intimacy and communication were relatively high in Facebook. Facebook showed higher values in attributes of interaction, sharing, entertainment, intimacy and communication. Twitter shows the relatively high scores for information and connection. Regarding interaction, Facebook shows higher scores than Twitter and Cyworld. For connection, Cyworld showed a significantly lower score than Twitter and Facebook. Cyworld was separated from the others in the light of communication. Cyworld is relatively weak in communication as it is limited to the message exchanges. The results will help in identifying major attributes for each SNS and classifying SNS.

An Experimental Investigation of Boussinesq's Theoretical Value of Vertical Stress Increment in Sandy Soil Mass Caused by Surface Strip Loading (지표면 띠하중 재하에 따른 사질토지반 지중연직응력 증가량의 Boussinesq 이론값에 대한 실험적 고찰)

  • Lim Jong-Seok
    • Journal of the Korean Geotechnical Society
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    • v.20 no.9
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    • pp.5-15
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    • 2004
  • It is worthwhile to verify the vertical stress distribution in soil mass for rigorous design of foundation. A series of laboratory model tests were performed to investigate the Boussinesq's theory on vertical stress increment in sandy soil mass caused by surface loading. The test results were also compared with Boussinesq's theoretical values. The Boussinesq's theoretical values were always smaller than test results under the footing regardless of depth. Outside of the footing the values were larger than the measured stress at the depth of just footing width. The theory and the test showed similar results when the depth reached two and three times the footing width. The vertical stress decreased as the applied load increased. These trends were confirmed to be valid for the considered range of the relative density of sand and/or the width of footing. More accurate values can be acquired by correcting the theoretical values using these results when Boussinesq's theory is used.

Continuous force excited bridge dynamic test and structural flexibility identification theory

  • Zhou, Liming;Zhang, Jian
    • Structural Engineering and Mechanics
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    • v.71 no.4
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    • pp.391-405
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    • 2019
  • Compared to the ambient vibration test mainly identifying the structural modal parameters, such as frequency, damping and mode shapes, the impact testing, which benefits from measuring both impacting forces and structural responses, has the merit to identify not only the structural modal parameters but also more detailed structural parameters, in particular flexibility. However, in traditional impact tests, an impacting hammer or artificial excitation device is employed, which restricts the efficiency of tests on various bridge structures. To resolve this problem, we propose a new method whereby a moving vehicle is taken as a continuous exciter and develop a corresponding flexibility identification theory, in which the continuous wheel forces induced by the moving vehicle is considered as structural input and the acceleration response of the bridge as the output, thus a structural flexibility matrix can be identified and then structural deflections of the bridge under arbitrary static loads can be predicted. The proposed method is more convenient, time-saving and cost-effective compared with traditional impact tests. However, because the proposed test produces a spatially continuous force while classical impact forces are spatially discrete, a new flexibility identification theory is required, and a novel structural identification method involving with equivalent load distribution, the enhanced Frequency Response Function (eFRFs) construction and modal scaling factor identification is proposed to make use of the continuous excitation force to identify the basic modal parameters as well as the structural flexibility. Laboratory and numerical examples are given, which validate the effectiveness of the proposed method. Furthermore, parametric analysis including road roughness, vehicle speed, vehicle weight, vehicle's stiffness and damping are conducted and the results obtained demonstrate that the developed method has strong robustness except that the relative error increases with the increase of measurement noise.