• The Korean Journal of Health Service Management
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• v.6 no.3
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• pp.141-155
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• 2012

The purpose of this study is to analyze the effects of job stress on job attitude among nurse practitioners, determine moderating effects of perceived organizational support in this process, and provide preliminary data to devise a scheme for managing job attitude effectively in nursing manpower. The research model was composed of 7 sub-variables of job stress, which was a independent variable; job attitude, which was a dependent variable, was divided into job satisfaction and organizational commitment; and variables of moderating effects included perceived organizational support. The data for empirical analysis of the model were collected from 300 nurses working in one university hospital and two general hospitals in Busan by using structured self-administered questionnaires. The main results of empirical analysis were as follows: Perceived organizational support was effective in preventing job stress from worsening job attitude. Moderating effects of perceived organizational support were found to exist in relations between job stress and organizational commitment. These results imply that a sense of organizational support has both direct and moderating effects on job attitude and can be a good means of managing job attitude.

• Journal of Welding and Joining
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• v.9 no.1
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• pp.40-47
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• 1991

The most fatigue tests carried out under the either stress or strain control, but machines and structures had taken variable stress. This variable stress was treated as statistics based on p-type distributions. In this paper, the cumulative fatigue damage of SM45C round bar specimens having a center hole resulting from block loading with p-distributions in rotating bending conditions, is presented. The value of p was changed in the range from 0.25 to 1; 0.25, 0.5, 0.75, 1. The following conclusions were obtained through the constant stress amplitude experiments and the block loading experiments. (1) In constant loading test, fatigue life was affected by cyclic rate. From experimental data, N$_{f}$ (100cpm)/N$_{f}$(3000cpm)equal to 0.56. (2) In case of the cyclic rate 100cpm and 3000cpm, at the high stress amplitude level the crack propagation life N$_{*}$f is longer than the low stress amplitude level. (3) Miner's hypothesis may be valid for p=0.75 and prediction of fatigue life by Haibach's method agree with experimental data well for the case p=0.5, while the modified Miner's method agree with experimental data well for the case p=0.25.5.

• Safety and Health at Work
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• v.1 no.1
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• pp.87-97
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• 2010

Objectives: This study was conducted to investigate the effect of trust on work stress. Trust can be classified into three dimensions; social trust, institutional trust, and trust in others. The relationship between work stress and trust is regarded as having three components. First, trust has an influence on work stressors as an antecedent variable; secondly, trust modifies the effect of the various stressors, and finally, trust is one of the stressors. Methods: Data for this study was collected by interviews and self-administered structured questionnaires from 376 Korean and 77 Japanese workers in small businesses. Subjects were selected by two stage stratified random sampling from the working population of manufacturing industries. Results: Three different positions of trust are significantly related with the stress causation web. Social trust, institutional trust and trust in others significantly influence different work stressors in both Korean and Japanese workers. Three different kinds of trust influence work stressors among Korean workers, but institutional trust has no impact on work stressors among Japanese workers. As a moderating variable for perceived stress, distrust in an employer is statistically significant in both groups. However, stress symptom prevalence among Korean workers is modified by caution, trust in career development, and distrust in co-workers, but that of Japanese workers is modified only by distrust in employer. Job satisfaction of Korean workers is affected by general trust, utility of relation, institutional trust and trust in employer, but among Japanese workers, caution, reputation and trust in employer have influence on job satisfaction. Conclusion: The effect of trust on work stress, perceived stress, stress reaction and job satisfaction are different among Korean workers and Japanese workers. Three dimensions of trust have three different positions as antecedent, moderating and mediating factors in stress causation.

• Journal of the Korean Home Economics Association
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• v.36 no.9
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• pp.49-62
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• 1998

This paper investigates the parenting stress of fathers who have preschooler. At first, a causal model constructed, including the parenting stress as a dependent variable and the psychological characteristics of paternal self-esteem and parenting efficacy as parameters. Based on the change of parenting stress, self-esteem and parenting efficacy according to various pertinent to fathers, the causal effect of various variables effecting on the paternal parenting stress is analyzed. The SPSS PC program was used for the statistical analysis, where fully exploited were frequencies, percentages, means, standard deviations, Cronbach α, one-way analysis(ANOVA), path analysis. The results can be summarized into 3 parts, in conclusion: 1) The younger a father is, the higher paternal self-esteem becomes. Paternal self-esteem trend was there, for a father who is a member of large family, and for a father whose education level is high, and for a father whose occupation is professional. Regarding parenting sense of competence, a father shows confidence when he has more income, more educated and less children. 2) The variable analysis effecting on the parenting stress dut to the paternal environment shows that a father feels more stress when his income is less and his spouse is working. The sub-factor analysis on the parenting stress shows that 'typical stress dut to the parenting' increases when his income is less and his spouse is working, and 'pressures pertaning to the parental role and distress' increases for a father with less income, working spouse, less educated and non-professional job. Further 'guilty to the parenting by others' shows higher for a father with less income and a working spouse. 3) The path analysis, which were performed to check the causality of the parenting stress dut to various variables, shows that the self-esteem and the parenting efficacy are significant factors directly effecting on the paternal parenting stress, and the job-satisfaction and marriage-satisfaction are significantly effecting on the parenting stress both directly and indirectly.

• Structural Engineering and Mechanics
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• v.11 no.4
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• pp.443-460
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• 2001

This paper presents an effective application of a variable-node axisymmetric solid element designated as AQV (Axisymmetric Quadrilateral Variable-node element). The variable-node element with physical midside nodes helps to overcome some problems in connecting the different layer patterns on a quadrilateral mesh in the adaptive h-refinement. This element alleviates the necessity of imposing displacement constraints on irregular (hanging) nodes in order to enforce the inter-element compatibility. Therefore, the elements with variable mid-side nodes can be used effectively in the local mesh refinement for the axisymmetric structures which have stress concentrations. A modified Gaussian quadrature should be adopted to evaluate the stiffness matrices of the variable-node elements mainly because of the slope discontinuity of assumed displacement within the elements. Some numerical examples show the usefulness of variable-node axisymmetric elements in the practical application.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2162-2171
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• 1993

Geneal Structure optimization is utilized to minimize the weight of structures while satisfying constraints imposed on stress, displacements and natural frequencies, etc. Sandwich structures consist of inside core and outside face sheets. The selected sandwich structures are isotropic sandwich beams and isotropic sandwich plate. The face sheets are treated as membrane and assumed to carry only tensions, while the core is assumed to carry only transverse shear. The characteristic of the varying area are considered by adding the projected component of the tension to the transverse shear. The bending theory and energy method are adopted for analyzing sandwich beams and plates, respectively. In the optimization process, the cost function is the weight of a structure, and a deflection and stress constraints are considered. Design variable are thickness and tapering coefficients which determine the shape of a structure. An existing optimization code is used for solving the formulated problems.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.10
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• pp.1380-1387
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• 2000

The existing theoretical models for steady two-dimensional free convective laminar film condensation of pure saturated or superheated vapor under atmospheric pressure on isothermal vertical wall have been reviewed. To investigate the effects such as inertia, thermal convective and liquid-vapor interface shear stress, the models of constant or variable properties in liquid film for condensation of saturated vapor are compared in detail with Nusselt model. Also, for condensation of superheated vapor, the effects of superheated temperature and variable properties in liquid and vapor layers are examined and then a new correlation is proposed to predict the heat transfer. The results are in good agreement with the Shang's correlation within 2% errors.

• Journal of the Korean Magnetics Society
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• v.3 no.1
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• pp.61-64
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• 1993

We have constructed a hysteresis loop tracer in order to measure the magnetic properties of amorphous wires under variable tensile stress. It has a force range of 0 N to 20 N and a magnetizing frequency of 1 kHz to 20 kHz. Using the ac-hysteresis loop tracer, we can measure the magnetic properties(maximum magnetic induction $B_{max}$, residual magnetic induction $B_{r}$, coercive field strength $H_{c}$, etc.) of amorphous wires with precision of 1% under variable tensile stresses.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.31-36
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• 2000

The existing theoretical models for steady two-dimensional free convective laminar film condensation or pure saturated or superheated vapor under atmospheric pressure on isotheraml vertical wall have been reviewed. To investigate the effects of inertia, thermal convective and liquid-vapor interface shear stress, the models of constant or variable properties in liquid film for condensation of saturated vapor are compared in detail with Nusselt model. Also, for condensation of superheated vapor the effects of superheated temperature and variable properties in liquid and vapor layer are examined and then new correlation is proposed to predict the heat transfer. The results are in good agreement with the Shang's correlation within 2% errors.

• Structural Engineering and Mechanics
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• v.22 no.2
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• pp.131-150
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• 2006

Exact analytical solutions for in-plane static problems of planar curved beams with variable curvatures and variable cross-sections are derived by using the initial value method. The governing equations include the axial extension and shear deformation effects. The fundamental matrix required by the initial value method is obtained analytically. Then, the displacements, slopes and stress resultants are found analytically along the beam axis by using the fundamental matrix. The results are given in analytical forms. In order to show the advantages of the method, some examples are solved and the results are compared with the existing results in the literature. One of the advantages of the proposed method is that the high degree of statically indeterminacy adds no extra difficulty to the solution. For some examples, the deformed shape along the beam axis is determined and plotted and also the slope and stress resultants are given in tables.