• Geotechnical Engineering
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• v.13 no.4
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• pp.149-162
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• 1997

A series of torsion shear tests were performed to study the strength characteristics of sand under various stress paths during rotation of principal stress. These results can be classified into two groups of 25cm and 40cm according to the height of specimen, and toy que was applied only in the clockwise direction. In this study, strength characteristics of sand for the principal stress ratio in torsion sheartests were investigated and their results were compared with Lade's failure criterion. And the effect for specimen was considered. From the results of tests, friction angle of sand was affected by the deviatoric principal stress ratio $b:(\sigma_2 -\sigma_s)/(\sigma_2, -\sigma_3)$Failure strength of sand was determined not by the stress paths but by the current stress state. From comparison of specimens on 25cm and 40cm height, effect of end restraint could not be found. In the test where b is over 0.5 due to extension force, necking phenomenon by the strain localization was found.

• Journal of the Korean Home Economics Association
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• v.37 no.6
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• pp.59-76
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• 1999

This study was to investigate casual relation of psychological well-being and quality of life of married couples. For the data set 434 married couples living in Pusan, Korea were chosen. The data were analyzed using M, SD, t-test, Pearson's correlation, multiple regression, and path analysis. The findings of this study are as follows; First, marital satisfaction and the level of quality of life are higher for husbands than wives. Whereas psychological distress is higher for wives than husbands. Second, for husbands, husband's level of education, job satisfaction, husband's housework participation, and job stress have significant effect on marital satisfaction. For wives, wife's level of education, husband's housework participation, and husband's job stress have significant effect on marital satisfaction. Third, for husbands, job satisfaction and job stress have significant effect on psychological distress. For wives, husband's job stress have significant effect on psychological distress. Fourth, for husbands, job stress, marital satisfaction and psychological distress have significant direct effect on quality of life. Besides, husband's age, husband's level of education, job satisfaction, job stress, husband's housework participation, and marital satisfaction are indirectly associated with quality of life. For wives, marital satisfaction and psychological distress have significant direct effect on quality of life. Besides, wife's level of education, husband's job stress, husband's housework participation, and marital satisfaction are indirectly associated with quality of life.

• Journal of the Korean Ceramic Society
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• v.33 no.1
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• pp.83-91
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• 1996

Monolithic AlN and AlN-W composites were fabricated by pressure-less sintering at 190$0^{\circ}C$ under nitrogen atmosphere and the influences of tungsten phase on the microstructure and mechanical properties were investi-gated. In the fabrication of sintered specimen no additive was used. And monolithic AlN showed substantial grain growth and low relative density. AlN-W composites were fully densified and grain growths of matrix were inhibited. The densification behavior of composites were inferred to be achieved through the liquid phase sintering process such as particle-rearrangement and solutino-reprecipitation. Also the oxid phases which is expected to form liquid phases duringsintering process were detected by XRD analysis. As the tungsten volume content increases fracture strength was decreased and fracture toughness was increased. It was suppo-sed that the strength decrease of composites with tungsten content was due to existence of interface phases. The subcritical crack growth behavior was observed from the stress-strain curve of composites. The effect of the secondary phase and interface phases on toughness in crease were studied through observation of crack propagation path and the influence of residual stress on crack propagation was investigated by X-ray residual stress measurement. In the result of residual stress measurement the compressive stress of matrix in composi-test was increased with tungsten volume content and the compressive stress distribution of matrix must have contributed to the inhibition of crack propagation.

• The Research Journal of the Costume Culture
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• v.23 no.2
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• pp.270-283
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• 2015

The purpose of this study was to investigate the relationship between working environment and quality of life of fashion vendor company workers by using working environment variables such as job stress, job burnout, job satisfaction, and turnover intention. Preliminary test was conducted by interviewing fashion vendor company workers in order to find out factors that were more suitable for their working environment. Main survey was conducted to 200 fashion vendor company workers and 194 responses were analyzed. The results of correlation analysis showed that job stress, job burnout, job satisfaction, turnover intention, and factors of quality of life had significant relationships. Boss stress, role stress, achivement decrease, and personal condition satisfaction showed a significant relationship with turnover intention. The results of path analysis showed that job stress had a positive relationship with job burnout and job burnout had a negative relationship with job satisfaction. Both job stress and job burnout had a positive relationship with turnover intention, whereas job satisfaction had a negative relationship with turnover intention. Also, the results showed that job burnout and turnover intention had a negative relationship with quality of life of fashion vendor company workers, whereas job satisfaction had a positive relationship with quality of life of fashion vendor company workers.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.7
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• pp.899-906
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• 2011

Generally, load conditions of machine or structure in fatigue destruction is occurred not under single load conditions but under mixed load conditions. However, the experiment under mixing mode is insufficient because of no having test standard to the behavior of crack under mixing mode and variety of test methods, and many tests are required. In this paper measured crack direction path by created figure capture system when a experiment. Also, we studied by comparison the behavior of crack giving the change of stress ratio and inserting beach mark. Through the test under mixing mode, advancing path of crack is indicated that advancing inclined angle ${\Theta}$ (direction of specimen length) has increased depending on the increase of mixed mode impaction. It is indicated that according to the increase of mixed mode loading condition impaction under mixing mode, advancing speed of crack gets slow. Also, we found that inner crack(cross section of specimen) is progressed more rapidly than outer crack based on data through beach mark.

• Computers and Concrete
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• v.20 no.1
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• pp.85-97
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• 2017

With a special attention to the different stages of a typical loading path travelled in a fluid confined concrete test, this paper introduces a physically consistent model for the stress-strain curve of actively confined normal-strength concrete in the axial direction. The model comprises of the five elements of: (1) a criterion for the peak or failure strength, (2) an equation for the peak strain, (3) a backbone hydrostatic curve, (4) a transient hardening curve linking the point of departure from the hydrostatic curve to the failure point, and finally (5) a set of formulas for the post-peak region. Alongside, relevant details and shortcomings of existing models will be discussed in each part. Finally, the accuracy and efficiency of the proposed model have been verified in a set of simulations which compare well with the experimental results from the literature.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.83-93
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• 2003

This research, in order to study the effects of initial shear stress of anisotropically consolidated sand that has 0.558% fines, performed several undrained static and dynamic triaxial test. To simulate the real field conditions, loose and dense samples were prepared. Besides, the cyclic shear strength of Nakdong River sand under various combinations of initial static shear stress, stress path, pore water pressure and residual strength relationship was studied. By using Bolton's theory, peak internal friction angle at failure which has considerable effects on the relative density and mean effective stress was determined. In p'- q diagram, the phase transformation line moves closer to the failure line as the specimen's initial anistropical consolidation stress increases. Loose sands were more affected than dense sands. The increase of consolidation stress ratio from 1.4 to 1.8 had an effect on liquefaction resistance strength resulting from the increase of relativity density, and showed similar CSR values in dense specimen condition.

• Journal of Hospice and Palliative Care
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• v.18 no.4
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• pp.285-293
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• 2015

Purpose: This study was conducted to explore the effects of attitude to death in hospice and palliative professionals on their terminal care stress, and to analyze relationships among variables related to the two aforementioned parameters, such as depression and coping strategies. Methods: Participants were 131 hospice and palliative professionals from the cancer units of two tertiary hospitals and two general hospitals, two hospice facilities, two geriatric hospitals, and two convalescent hospitals in J province. Data were collected from April through June 2015 and analyzed using t-test, factor analysis, ANOVA ($Scheff{\acute{e}}$ test), ANCOVA, and Pearson's correlation and a path analysis using the SPSS/WIN 21.0 and AMOS 18.0 programs. Results: The score for attitude to death was low (2.63), and that for depression was 0.45. Among all, 16.0% of the participants showed need for depression management. They scored 3.82 on terminal care stress. The subcategory with the highest mark was inner conflicts on limitation given availability of medical services (4.04). The score on coping strategy was low (3.13). They used passive coping strategies such as interpersonal avoidance (4.03), fulfilling basic needs (3.65) such as sleeping or eating. Attitudes to death had a direct negative effect on the terminal care stress level and indirectly affected through depression and fulfilling basic needs (CS2). Conclusion: It is necessary to provide hospice and palliative professionals with education on death and dying, as well as access to programs that provide emotional support and promote positive cognition of death and dying.

• Geotechnical Engineering
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• v.14 no.4
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• pp.129-140
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• 1998

Elasto-plastic finite element analysis of geotechnical boundary value problems necessitate the stress integration for the known strain increments. For the elasto-plastic constitutive model, the stress integration is generally achieved by numerical schemes, because analytical integration is impossible for general strain path. In this case, the accuracy of numerical stress integration has an important role on the overall accuracy of nonlinear finite element solution. In this study, the Sloan's substepping method which is one of explicit integration methods has been adopted and iris applicability has been checked. The unstability and inaccuracy of ifs results initiated from initial stress level were revealed. So. a new modified numerical integration method which employs the basic concept of modified Euler scheme for error control is proposed and accuracy and stability of the solutions are confirmed by triaxial test simulation.

• Geotechnical Engineering
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• v.5 no.3
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• pp.19-28
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• 1989

This study has been carried out as a fundamental course for the analysis of the constitutive- equation for the materials like sands being hardened during Ehear. For this aim, experimentall tests with variable stress paths for the concrete material are performed using the cubical multi- axial test in which the three principle stresses are arbitrarily controlled. Stress-strain behaviors. and strength characteristics are suggested in octahedral planes. Various tests such as HC, CTC, . TC, 55 are performed. The main results summarized are as follows; 1. The order of strength from the largest to the smallest is CTC, TC, SS, and TE test. 2. The octahedral Ehear strength of concrete specimens is dependent upon the stress path(8) 3. There is a direct relation between strength and confining pressure. 4. The ultimate envelopes in the octahedral planes are non-circular-cone shaped. 5. Any ultimate criteria used to predict the strength behavior of concrete must include thin effect of the tensile stresses.