• Journal of the East Asian Society of Dietary Life
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• v.14 no.2
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• pp.93-102
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• 2004

This study investigated the relationship among the flight stress, disease and eating behavior of the Airline cabin crews. Self administered questionnaires were collected from three hundred and twenty cabin crews. Statistical data analysis was completed using a SPSS v.10.0 program. The results were summarized as follows: Before the flight, the maladaptation to the oversea foods was the most common stress for the crews less than one year flight experience. During the flight, fastidious arrangement and loss of appetite due to overwork were the most common stresses. After the flight, anorexia due to jet lag was the most common stress. Backache and stomachache were the most common job-related ailments of the airline cabin crews. During the flight, the intakes of carbonated drinks and coffee were most common. After the flight, water was the most common drink they consumed.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.1
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• pp.10-24
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• 2015

This study introduces a fatigue assessment procedure using mesh-insensitive structural stress method based on the Common Structural Rules for Bulk Carriers by considering important factors, such as mean stress and thickness effects. The fatigue assessment result of mesh-insensitive structural stress method have been compared with CSR procedure based on equivalent notch stress at major hot spot points in the area near the ballast hold for a 180 K bulk carrier. The possibility of implementing mesh-insensitive structural stress method in the fatigue assessment procedure for ship structures is discussed.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.791-799
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• 2005

We consider two components parallel system in which the lifetimes have the bivariate Pareto model with bivariate random censored data. We assume that bivariate Pareto model is affected by common stress which is independent of the lifetimes of the components. We obtain estimators for the system reliability based on likelihood function and relative frequency. Also we construct approximated confidence intervals for the reliability based on maximum likelihood estimator and relative frequency estimator, respectively. Finally we present a numerical study.

• Structural Engineering and Mechanics
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• v.11 no.5
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• pp.565-574
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• 2001

Experimental investigation into the behaviour of half-scale brick masonry panels were conducted under cyclic loading normal to the bed joint and parallel to the bed joint. For each cycle, full reloading was performed with the cycle peaks coinciding approximately with the envelope curve. Unloading, however, was carried out fully to zero stress level and partially to two different stress levels of 25 percent and 50 percent of peak stress. Stability point limit exhibits a unique stress-strain curve for full unloading but it could not be established for partial unloading. Common point limit was established for all unloading-reloading patterns considered, but its location depends on the stress level at which unloading is carried to. Common point curves were found to follow an exponential formula, while residual strains versus envelope strains can be expressed by a polynomial function of a single term. The relation between residual strain and envelope strain can be used to determine the stress level at which deterioration due to cyclic loading began.

• Journal of the Korean Data and Information Science Society
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• v.14 no.1
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• pp.113-118
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• 2003

In this paper, We assume that strengths of two components system follow a bivariate pareto distribution. And these two components are subjected to a common stress which is independent of the strength of the components. We obtain maximum likelihood estimator(MLE) for the system reliability from stress-strength relationship. Also we derive asymptotic properties of the MLE and present a numerical study.

• Structural Engineering and Mechanics
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• v.16 no.4
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• pp.405-422
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• 2003

Scaled brick masonry panels were tested under cyclic unialxial compression loading to evaluate its deformation characteristics. An envelope stress - strain curves, a common point curves and stability point curves were obtained for various cyclic test conditions. Loops of the stress-strain hysteresis were used to determine the energy dissipation for each cycle. Empirical expressions were proposed for the relations between energy dissipation and envelope and residual strains. These relations indicated that the decay of masonry strength starts at about two-third of peak stress.

• Research in Community and Public Health Nursing
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• v.10 no.1
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• pp.252-261
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• 1999

The purpose of this study was to investigate the daily stress and stress coping behavior of elementary school children. The subjects for this study were 372 children fourth, fifth and sixth graders from an elementary school in Pusan. We adopted Won - Joo Chung's research instrument (1997) for measuring stress and coping behavior in this study. Statistical techniques such as frequency, percentage, mean, standard deviation, order, and Pearson correlation were used to examine the research questions of this study. The results of this study were as follows: 1. The most common instance of stress to be experienced by all children was the stress from school life, followed by social pressures, individual pressures and family environment. 2. A positive revaluation was the most commonly used stress-coping behavior, followed by behavioral mood conversion, spiritual support, problem-facing behavior, an information search for problem-solving, physical separation for emotional relaxation, avoidance, emotional aggressiveness and emotional expression. 3. Stress-coping behavior had a positive and significant correlation with the stress score(r = .4391, p= .000). In conclusion, the stress from school life was the most common experienced by all children. While independent effort in problem-solving was unsufficient, stress coping behavior had positive results. Therefore, this study verified the necessity of minimizing the stress children experience from school life and of helping them attain desirable stress-coping behaviors.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.6
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• pp.298-306
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• 2002

We performed an safety evaluation on constructing of a common grounding system for electrical railway in view of its efficacy and technical fit. In order to compare the conventional grounding method, which has been individually conducted, with the common grounding with all ground wires connected in common to the counterpoise buried below the surface of the earth in parallel with rail, we set up scenarios with several cases of fault and load conditions in Chungbuk railway sections with the common grounding system. Based on models for railway conductors including the grounded system, line Parameters of railway power system are computed. The circuit model for power system with up and down lines, auto-transformers and railway substations is used to compute impedances of counterpoise and substation ground net. For each scenario with faults and operation conditions of railway, the induced potentials on signal and communication lines are also computed. It is shown that the common grounding for Chungbuk railway is superior experimentally to the conventional method in three respects: (1) the lower rail potentials during operation of railway in line, (2) the lower rail potentials for short-circuit faults between catenary and rail, and (3) the lower stress voltages on signal and communication lines for short-circuit or ground faults. The analysis results confirm that the grounding system for electric railway is required to be built by the common grounding and be evaluated on its safety in design.

• Journal of the Korean Data and Information Science Society
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• v.15 no.3
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• pp.655-662
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• 2004

In this paper, we assume that strengths of two components system follow a type II bivariate Pareto model with bivariate type I censored data. And these two components are subjected to a common stress which is independent of the strengths of the components. We obtain estimators for the system reliability based on likelihood function and relative frequency, respectively. Also we construct approximated confidence intervals for the reliability based on maximum likelihood estimator and relative frequency estimator, respectively. Finally we present a numerical study.

• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.277-284
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• 1998

The reliability and an estimate for it are derived for series-parallel and parallel-deries stress-strength model under assumption that all components are subjected to a common stress. We also obtain the asymptotic normal distribution of the estimate.