• Structural Engineering and Mechanics
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• 제40권2호
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• pp.257-277
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• 2011

In this paper the geometrically nonlinear continuum plate finite element model, hitherto not reported in the literature, is developed using the total Lagrange formulation. With the layerwise displacement field of Reddy, nonlinear Green-Lagrange small strain large displacements relations (in the von Karman sense) and linear elastic orthotropic material properties for each lamina, the 3D elasticity equations are reduced to 2D problem and the nonlinear equilibrium integral form is obtained. By performing the linearization on nonlinear integral form and then the discretization on linearized integral form, tangent stiffness matrix is obtained with less manipulation and in more consistent form, compared to the one obtained using laminated element approach. Symmetric tangent stiffness matrixes, together with internal force vector are then utilized in Newton Raphson's method for the numerical solution of nonlinear incremental finite element equilibrium equations. Despite of its complex layer dependent numerical nature, the present model has no shear locking problems, compared to ESL (Equivalent Single Layer) models, or aspect ratio problems, as the 3D finite element may have when analyzing thin plate behavior. The originally coded MATLAB computer program for the finite element solution is used to verify the accuracy of the numerical model, by calculating nonlinear response of plates with different mechanical properties, which are isotropic, orthotropic and anisotropic (cross ply and angle ply), different plate thickness, different boundary conditions and different load direction (unloading/loading). The obtained results are compared with available results from the literature and the linear solutions from the author's previous papers.

• 동의신경정신과학회지
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• 제34권4호
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• pp.385-401
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• 2023

Objectives: To review clinical research trends of herbal medicine treatment for alcohol use disorder. Methods: Three domestic databases and eight foreign databases were used to search for published articles by November 1, 2023 in each database. A total of 9 studies were included. Results: There were eight randomized control studies and one non-randomized control study. All randomized control studies were designed with 2-arm paralleled. The non-randomized control study was designed with 2-arm crossover. The most commonly used prescriptions were Kudzu extract capsules and Seoganhaeul capsules. The most used herbs were Puerariae Radix, Hyperici Perforati Herba, and Acanthopanacis Senticosi Radix et Rhizoma seu Caulis. Conclusions: Traditional herbal medicine might be effective in alleviating drinking behavior, physical problems, and psychological problems of patients with alcohol use disorder. However, the limited number of included studies suggests that further methodologically rigorous research studies on herbal medicine treatment for alcohol use disorder are needed in the future.

• 성인간호학회지
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• 제19권4호
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• pp.567-582
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• 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.

• 한국의류산업학회지
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• 제9권2호
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• pp.229-236
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• 2007

Many researchers have focused on consumers' clothes purchase behavior, These researches could not reflect the characteristics of the single consumers' clothes purchase behavior. In addition, little has been written on the single consumer. The purposes of this study are to identify the concept and psychologic characteristics of single consumer and investigate the effects of single consumers' psychologic characteristic and susceptibility to interpersonal influence on clothes shopping pursuing value. Also, It was analyzed how single consumer' pursuing values are different based on the type of single motivation. To test research problems, Data were collected by means of a survey questionnaire, which was sent to 300 single in Pusan and Ulsan. In total, 274 were returned and 14 were unusable because of unacceptable levels of missing data. The Results were summarized as follows: First, self-efficacy, informative and normative influence were positively related to utilitarian pursuing value employee satisfaction. Also, self-efficacy, variety seeking, innovativeness and informative influence had a positive effect on hedonic pursuing value. Second, voluntary single and nonvoluntary single group had different perceptions about self-efficacy, variety seeking, innovativeness, informative influence, and hedonic pursuing value.

• Computers and Concrete
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• 제21권1호
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• pp.47-54
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• 2018

Artificial neural network models can be successfully used to simulate the complex behavior of many problems in civil engineering. As compared to conventional computational methods, this popular modeling technique is powerful when the relationship between system parameters is intrinsically nonlinear, or cannot be explicitly identified, as in the case of concrete behavior. In this investigation, an artificial neural network model was developed to assess the residual compressive strength of self-compacted concrete at elevated temperatures ($20-900^{\circ}C$) and various relative humidity conditions (28-99%). A total of 332 experimental datasets, collected from available literature, were used for model calibration and verification. Data used in model development incorporated concrete ingredients, filler and fiber types, and environmental conditions. Based on the feed-forward back propagation algorithm, systematic analyses were performed to improve the accuracy of prediction and determine the most appropriate network topology. Training, testing, and validation results indicated that residual compressive strength of self-compacted concrete, exposed to high temperatures and relative humidity levels, could be estimated precisely with the suggested model. As illustrated by statistical indices, the reliability between experimental and predicted results was excellent. With new ingredients and different environmental conditions, the proposed model is an efficient approach to estimate the residual compressive strength of self-compacted concrete as a substitute for sophisticated laboratory procedures.

• Journal of Preventive Medicine and Public Health
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• 제40권3호
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• pp.218-226
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• 2007

Objectives : This study examined the relationship of parent-related negative life events with mental health and delinquent behaviors among Korean adolescents. Methods : A total of 2,976 high school first-grade pupils (1,498 boys & 1,478 girls) taking part in the third wave of Korean Youth Panel Survey completed a self-administered questionnaire regarding parent-related life events, depressive feelings, suicidal ideation, delinquent behaviors, demographic characteristics, parental socioeconomic status, social support, and social capital. Data analyses were conducted using multivariate logistic regression. Results : After adjusting for all covariates, the more parent-related negative life events adolescents experienced throughout their whole life, the more likely adolescent were to have mental and behavioral problems. A significant dose-response relationship between them was more clearly observed in girls than in boys. The experience of parentrelated negative events during childhood was significantly associated with suicidal ideation and delinquent behaviors for boys, and with depressive feelings for girls during adolescence. Indeed, parental social support, social capital, and having a close friend with delinquent behaviors, especially for girls, partially mediated the relationship between parent-related negative life events and both outcomes. Conclusions : The study showed a clear dose-response relationship of frequency of parent-related negative life events with poor mental and behavioral health for both genders. The residual effect of being exposed to parent-related events during childhood on mental health and delinquent behaviors during adolescence still remained.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5627-5632
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• 2012

Background: The aim of the study was to determine the prevalence of shisha smoking and associated factors among medical students in Malaysia. Materials and Methods: A cross-sectional study was conducted at the Management and Science University from December 2011 until March 2012. The questionnaire consisted of five sections including socio-demographic, social environment, knowledge about shisha, psychosocial factors, and personal shisha smoking behavior. Obtained data were analyzed using Statistical Package for the Social Sciences (SPSS 13). T-test was used to determine the relationships between shisha smoking and socio-demographic characteristic. Results: A total number of 300 medical students participated in this study. Mean age was $22.5{\pm}2.5$ years. The majority were female, Malay, single, from urban areas (67%, 54%, 97%, 73%; respectively). The prevalence of shisha smoking among medical students was found to be 20%. The study revealed that many students believed that shisha does not contains nicotine, carbon monoxide, does not lead to lung cancer, dental problems and does not lead to cardiovascular diseases (25%, 20.7%, 22.3%, 29%, 26.7%; respectively). Age and sex were found to be significantly associated with smoking shisha status among medical students (p=0.029, p<0.001; respectively). Furthermore, having parents, siblings and friends smokers of shisha were found to be significantly associated with shisha smoking status (p<0.001, p<0.001, p<0.001; respectively). Furthermore, family problems, problems with friends, financial problems and university life were found to significantly associated with shisha smoking status among medical students (p<0.001, p=0.002, p<0.001, p=0.002; respectively). Conclusions: There is a high prevalence of shisha smoking and a poor knowledge about its impact on health among medical students. More attention is needed to focus on medical education in this regard. The policies that are currently employed in order to reduce the cigarettes smoking should be applied to shisha smoking and shisha products.

• 한국보육지원학회지
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• 제12권1호
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• pp.37-55
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• 2016

본 연구에서는 유아의 놀이성, 정서통제, 정서불안정이 또래놀이행동에 미치는 상대적 영향을 비교하기 위해 어린이집에 다니는 만 4세 및 5세 유아 209명을 대상으로 연구를 실시하였다. 본 연구에서는 유아의 놀이성을 측정하기 위해 '놀이성척도'를, 정서통제, 정서불안정을 측정하기 위해 '정서규제체크리스트'를, 또래놀이행동을 측정하기 위해 '또래놀이행동척도'를 사용하였다. 수집된 자료는 t-검증, 피어슨의 적률상관계수, 단계적 회귀분석을 통해 분석되었다. 본 연구의 결과는 다음과 같다. 첫째, 연령에 따라 유아의 또래놀이행동, 놀이성, 정서통제, 정서불안정에 차이가 있는 것으로 나타났다. 둘째, 유아의 놀이상호작용은 정서통제와 놀이성에 의해 영향을 받는 것으로 나타난 반면, 유아의 놀이방해와 놀이단절은 정서불안정과 놀이성에 의해 영향을 받는 것으로 나타났다. 이와 같은 연구결과에 기초하여 유아의 또래놀이행동에 영향을 미치는 정서 관련 변인의 중요성에 대해 논의한 후 향후 과제와 제언을 제시하였다.

• 한국식품조리과학회지
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• 제32권2호
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• pp.222-232
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• 2016

Purpose: Sodium intake in school meals is very high. Accordingly, many health problems have emerged. The objective of this study was to assess school dietitian's awareness and practice of sodium contents in urban and rural locations schools and suggest sodium reduction plan in school meal service. Methods: A total of 524 nationwide school dietitians from elementary, middle, and high schools in south Korea were surveyed using questionnaires to determine their awareness and practicing behavior for reducing high-salt contents in meals. Sodium reduction plan was then suggested accordingly. Results: Most school dietitians (83%, n=436) were aware of the necessities of sodium reduction in school meals. They were aware of optimum sodium levels at 700-1000 mg. However, the percentages of dietitians who had practicing behavior of using measuring utensils for seasoning were 20.7% (n=108), 14.9% (n=78), and 13.5% (n=71) in elementary, middle, and high schools, respectively (p<0.001). Dietitians in urban elementary and middle schools had significantly (p<0.01) higher practicing behavior of using measuring utensils compared to those in rural locations. Considering low levels of soup contents with high amount of leftover, the desirable soup portions to be reduced were '50-100 mL' (n=66, 12.7%) for elementary school and '100-150 mL' for middle school (n=62, 12.0%) and high school (n=57, 11.0%, p<0.001). Conclusion: Dietitians' awareness for sodium reduction was high but their practicing behavior was relatively low. Thus, continuous efforts are required to develop reduced-sodium menu by promoting the use of measuring utensils when preparing meals and by planning no soup meal day or educating students and teachers about the importances of reducing sodium in school meals.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.349-352
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• 2008

IPC 거더교(Incrementally Prestressed Concrete Girder Bridge)는 다단계 긴장을 이용하여 구조적 효율을 최대화하기 때문에 기존의 PSC-I형 거더교에 비하여 작은 단면에 큰 긴장력이 도입된다. 따라서 기존의 PSC-I형 거더교에 비하여 강성(stiffness)이 작아져서 장기적으로 큰 변형이 발생할 가능성이 있다. PSC 거더 연속교에서의 장기변형은 연속지점부의 응력에도 큰 변화를 일으키기 때문에 장기적 거동을 고려하지 않으면 구조물의 사용성 뿐만 아니라 안전성에도 문제를 일으킬 수 있다. 따라서 본 연구에서는 IPC 거더 연속교의 장기거동 모니터링을 통하여 예상범위를 초과하는 특이 거동의 발생을 포함한 IPC거더교의 장기적인 솟음 또는 처짐 특성을 파악하고자 하였다. 장기거동의 계측은 계측방법의 용이성과 정밀도에 대한 검토를 통하여 고정밀도의 토탈스테이션을 사용하였으며, 기존의 PSC-I형 거더교 공정과 차별되는 2차 긴장력 도입 공정부터 처짐을 계측하였다. 현재까지의 계측결과를 보면, IPC거더 연속교는 특이한 거동, 즉 과도한 솟음이나 처짐은 없었으며 장기구조해석 결과와 상당히 유사한 경향을 보였다.