• 한국학교보건학회지
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• 제21권2호
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• pp.61-73
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• 2008

Purpose: Several health behavior factors affect the incidence of type 2 diabetes. Especially, obesity, which causes insulin resistance, is the most important determinant of diabetes. Therefore, we expect the risk factors associated with insulin resistance and type 2 diabetes are affected by obesity and, additionally, the related factors with diabetes caused by obesity can be controlled. Methods: This study used data collected from the 2001 Korea National Health and Nutrition Examination Survey (KNHANES). A stratified multistage probability sampling method was applied and the final sample included 5,500 subjects over 30 years old who had completed necessary health examinations and health behaviors survey. Results: The risk factors associated with type 2 diabetes are affected by obesity. According to logistic regression model stratified by body mass index (BMI) and sex, abdominal obesity and age were the significant risk factors of diabetes regardless of sex and BMI. However, drinking, smoking, total energy consumption, and protein consumption were risk factors for women with normal BMI, while carbohydrate consumption was a risk factor for man with normal BMI. Sleeping hours affected diabetes for women with obesity and fiber consumption was a risk factor for both women and men with obesity. In addition, statistically the family history of diabetes was a significant risk factor only in the group with normal weight, not in the group with obesity. Conclusion: The study results will provide information for implementing a regional initiative of type 2 diabetes prevention by BMI.

• The Journal of Asian Finance, Economics and Business
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• 제9권4호
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• pp.345-355
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• 2022

Excellent employees are those who take on extra responsibilities and commitments at work. Hence, employees must pay attention to out-of-role activities that can help the company perform better. When a person takes on more responsibilities than he can handle, they will have to deal with the issue of work-family balance. This paper examines how the consistency of WFC affects employees' organizational citizenship behavior (OCB) using the Resource Conservation Theory. This study uses empirical research methodologies to assess 417 employees as a sample. (1) When the matches of work-to-family conflict (WFC) and family-to-work conflict (FWC) are consistent, the employee self-control resource depletion level is lower, and OCB is higher in the "high-high" consistency matching state. (2) The "low-high" match had a higher OCB than the "high-low" match when the WFC and FWC matches were inconsistent. (3) In the process of WFC affecting OCB, the depletion of self-control resources acts as a mediating factor. (4) Emotional intelligence plays a moderating role in the whole model. The lower the emotional intelligence was, the stronger the positive relationship between the consistency of WFC, FWC, and self-control resource depletion was.

• 한국자동차공학회논문집
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• 제19권1호
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• pp.125-132
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• 2011

The dynamic characteristics of valve train are responsible for the dynamic performances of engine. We derived the equation of motion for 6 degrees of freedom model of the valve train. Computer model is also developed with flexible multibody model considering contact between components. The simulation results with these two models are compared with experimental results. We investigated the effect of the two spring models, TSDA (Translational Spring Damper Actuator) element and flexible body model, on the valve behavior and spring force. It is found that the dynamic behavior of the two models are not very different at normal operational velocity of the engine. By modeling contact between cam and tappet, the stress distributions of the cam were found. Using stress distribution obtained, contact width and contact stresses of the cam surface were calculated with Hertz contact theory.

• Journal of Biosystems Engineering
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• 제17권3호
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• pp.260-271
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• 1992

Fruits are generally subjected to mechanical forces during harvesting, handling, and transportation that may cause damage in the form of bruises, punctures, and cracks. In order to prevent damage, and insure better quality fruits for consumers, it is very essential to study physical properties of these materials. The studies were conducted to examine the effect of storage period, storage condition, and other factors, such as loading rate and initial strain, on the stress relaxation behavior of the fruit flesh, and develop nonlinear viscoelastic models to represent its stress relaxation behavior. The following results were obtained from the study : 1. Since the viscoelastic behavior of the fruits flesh was nonlinear, the behavior was satisfactorily modelled as follows ; $${\delta}({\varepsilon},\;t)={\varepsilon}^A[B\;{\exp}(-Ct)+D\;{\exp}(-Ft)+G(-Ht)]$$ But, for the every strain applied, the stress relaxation behavior of the fruit flesh, such as apple and pear, could be well described by the Generalized Maxwell model, respectively. 2. The effect of loading rate on the stress relaxation behavior was remarkable. The higher loading rate resulted in the higher initial stress, and the faster stress relaxation. 3. The higher initial strain resulted in the higher initial stress, and stress relaxed at the large initial strain was also much higher than at the small initial strain. 4. Stress relaxation rate and quantity stored in the fruits at the low temperature storage were much higher than those at the normal temperature storage in the same storage period. Also, in all fruits tested, the longer storage period was the more relaxation rate and quantity were shown. These trends in the normal temperature condition was the more significant than in the low temperature condition.

• Earthquakes and Structures
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• 제9권6호
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• pp.1233-1250
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• 2015

The behavior of reinforced concrete (RC) columns made from high strength materials was investigated experimentally. Six high-strength concrete specimen columns (1:4 scale), which included three with high-strength transverse reinforcing bars and three with normal-strength transverse reinforcement, were tested under double curvature bending load. The effects of yielding strength and ratio of transverse reinforcement on the cracking patterns, hysteretic response, shear strength, ductility, strength reduction, energy dissipation and strain of reinforcement were studied. The test results indicated that all specimens failed in splitting failure, and specimens with high-strength transverse reinforcement exhibited better seismic performance than those with normal-strength transverse reinforcement. It also demonstrated that the strength of high-strength lateral reinforcing bars was fully utilized at the ultimate displacements. Shear strength formula of short concrete columns, which experienced a splitting failure, was proposed based on the Chinese concrete code. To enhance the applicability of the model, it was corroborated with 47 short concrete columns selected from the literature available. The results indicated that, the proposed method can give better predictions of shear strength for short columns that experienced a splitting failure than other shear strength models of ACI 318 and Chinese concrete codes.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.225-230
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• 2009

From the view point of railway vehicle dynamics, the interaction between wheel and rail have an huge effect on the behavior of the vehicle. This phenomenon is an unique motion, only for railway vehicles. Furthermore, close investigation of the backgrounds of the interaction is the key to estimate the dynamic behavior of the vehicle, successfully. To evaluate the model including flexible bodies such as car body and catenary system of the next generation express train, it is necessary to develop proper dynamic solver including a wheel rail contact module. In this study, wheel-rail contact module is developed using the general purpose dynamic solver. First of all, the procedure for calculation of the wheel-rail contact force has been established. Generally, yaw angle of the wheelset is ignored. Sets of information are summarized as tables and splined for further uses. With this information, normal force and creep coefficient can be extracted and used for FASTSIM algorithm, which has been shown good reliability over years. Normal force and longitudinal, lateral force at the contact surface are also calculated. Those data are verified by commercial railway simulation program 'VAMPIRE'. This procedure and program can offer a basic process for estimation of the dynamic behavior and wear of the wheel-rail system, even while running on the curved rail. Finally, multi-dimensional inspection tool will be developed including the prediction of the derailment.

• 한국인공지능학회지
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• 제7권1호
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• pp.5-12
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• 2019

The study is to identify the factors influencing Chinese consumers' intentions to purchase organic food based on Theory of Planned Behavior (TPB) model. This research concentrates on the moderating effect of gender during the process. An offline investigation was used for the research purpose. Data for the study was gathered from February to March 2018. The total of 260 valid responses was used for this analysis. An online questionnaire was distributed through Email to Chinese consumers living in major cities of China and abroad to collect the data. Multi group analysis and model comparison were conducted to examine the moderating effect of gender. Our results support previous researches suggesting that gender moderates the relationship between attitude and behavioral intention. However, surprisingly, no significant moderating effect of gender on the relationship between subjective norms and behavioral intention was found. This paper revisited TPB antecedents and the moderating effect of gender focusing on Chinese organic food markets. The findings provide essential managerial implications to the marketers in this industry. Further research could examine whether TPB model can be applied to other potential purchasing groups.

• Computers and Concrete
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• 제20권5호
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• pp.529-537
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• 2017

Excessively elevated temperature can lead to cracks in prestressed concrete (PC) continuous bridge with box girder on the pier top at cement hydration age. This paper presents a case study for evaluating the behavior of PC box girder during the early hydration age using a two-stage computational model, in the form of computer program ANSYS, namely, 3-D temperature evaluation and determination of mechanical response in PC box girders. A numerical model considering time-dependent wind speed and ambient temperature in ANSYS for tracing the thermal and mechanical response of box girder is developed. The predicted results were compared to show good agreement with the measured data from the PC box girder of the Zhaoshi Bridge in China. Then, based on the validated numerical model three parameters were incorporated to analyze the evolution of the temperature and stress within box girder caused by cement hydration heat. The results of case study indicate that the wind speed can change the degradation history of temperature and stress and reduce peak value of them. The initial casting temperature of concrete is the most significant parameter which controls cracking of PC box girder on pier top at cement hydration age. Increasing the curing temperature is detrimental to prevent cracking.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1096-1101
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• 2008

Concrete is shown the time dependent behavior after placing. The time dependent behavior of normal strength concrete that is used usually in present, were already examined closely lots of parameters by several investigators. however, high strength concrete is that the material characteristics are not definite and the experimental data are lacking. So, The goal of this study is to propose the material characteristics models, and to develop the routine of the time dependent behavior above 60 MPa. The thermal conductivity, the specific heat, the moisture diffusion coefficient, and the surface coefficient are proposed the suitable models through the parametric study. The structural element is used the 8-node solid element. The matrix equation is developed considering the transient heat transfer and moisture diffusion theory. The application of the time dependent behavior is used the finite differential method.

• Journal of Mechanical Science and Technology
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• 제16권4호
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• pp.522-531
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• 2002

In order to study the thermal-hydraulic behavior of the cable-in-conduit-conductor (CICC), a numerical model has been developed. In the model, the high heat transfer approximation between superconducting strands and supercritical helium is adopted. The strong coupling of heat transfer at the front of normal zone generates a contact discontinuity in temperature and density. In order to obtain the converged numerical solutions, a moving mesh method is used to capture the contact discontinuity in the short front region of the normal zone. The coupled equation is solved using the finite element method with the artificial viscosity term. Details of the numerical implementation are discussed and the validation of the code is performed for comparison of the results with thse of GANDALF and QSAIT.