• Journal of the Korea institute for structural maintenance and inspection
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• v.1 no.1
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• pp.53-64
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• 1997

Recently, safety evaluation of structures has received great concern in this country. One major problem in safety evaluation is that the results are often quite different depending upon evaluation authority. This is mainly due to arbitrary selection of various modification factors when employing allowable stress method for safety evaluation, The purpose of the present study is, therefore, to establish a rational method to determine the modification factors, especially the stress modification factor and the deterioration modification factor based on visual examination. It is thought that the proposed method yields a rational and consistent result for safety evaluation and may efficiently be used for realistic evaluation of load capacity of bridge structures.

• Structural Engineering and Mechanics
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• v.57 no.5
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• pp.823-835
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• 2016

Using the Complementary Functions Method (CFM), a general solution for the one-dimensional steady-state thermal and mechanical stresses in a hollow thick sphere made of functionally graded material (FGM) is presented. The mechanical properties are assumed to obey the exponential variations in the radial direction, and the Poisson's ratio is assumed to be constant, with general thermal and mechanical boundary conditions on the inside and outside surfaces of the sphere. In the present paper, a semi-analytical iterative technique, one of the most efficient unified method, is employed to solve the heat conduction equation and the Navier equation. For different values of inhomogeneity constant, distributions of radial displacement, radial stress, circumferential stress, and effective stress, as a function of radial direction, are obtained. Various material models from the literature are used and corresponding temperature distributions and stress distributions are computed. Verification of the proposed method is done using benchmark solutions available in the literature for some special cases and virtually exact results are obtained.

• Journal of Oral Medicine and Pain
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• v.23 no.4
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• pp.309-326
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• 1998

In general, the major causative factor of halitosis is thought to be a sulfated compounds. Clusterin, a sulfated glycoprotein-2(SGP-2), is frequently found in diabetic conditions and cold stress conditions. The same result is werum glucose level to diabeteic and cold stress conditions that founded Clusterin. Therefore, this study was performed to examine Clusterin in the slivary glands under stress conditions before insulin injection I.M. Fourty rats were diveded into 3 groups ; 1) 10 rats of gorup I were selected as a control 2) 15 rats beloning to group II were bathed in cold water for 30 seconds twice a day 3) 15 rats in group III received cold stress and injected I.M. with insulin. The rats were sacrifeced at day 0, 3, 5, 7 and 10 of the experiment and the submandibular glands and parotid galnds were removed. RNAs were purified from the salivary of the salivary glands were subjected to Hematoxillin-Eosin stainings and examined under the light microscope. The obtained results were as follows : 1. With immunohistochemistric method, in normal control goup, Clusterin was moderately stained in the intercalated ductal cell of the submandibualr glands, mild stained in the striated ductal cell of the submandibular glands, heavily stained on the cytoplasm of the intercalated ductal cell in the mucous submandibular glands nad slightrly stained in the intercalated ductal cell of the paroted gland, expressed negativity in the acina cell. 2. With immunohistochemistric method, Clusterin slightly increased in the acina cell of the submandibular glands under stress condition at 3 days after experement, moderately stained at 5 days after experiment so revealed positive response. And hearily in the intercalated ductal cell and mildly lin the acina celluar eytoplasm of the parotid glands under stress condition at 3 days experiment. 3. With immunohistochemistric method, no remarkable differences are found between the normal control group and stress conditioned group that insulin administration was performed before. 4. In the stressor-giving group, Clusterin mRNA was porminently expressed in submandibular gland after 5 days after experiment, in parotid gland after 3 days after experiment, performed in immunoelectrophoresis method. 5. In the insulin-injected nad stressor-giving group, Clusterin mRNA was not observed in all experimental submandibular and parotid gland, performed in immunoelectrophoresis method.

• Journal of Korean Society of Steel Construction
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• v.12 no.2 s.45
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• pp.197-207
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• 2000

A transient heat transfer analysis and thermo-elastic analysis have been performed for the residual stress distribution on the fillet weldment used by finite element method. Specimen is fabricated single-pass fillet welding. This computation was performed for conditions including surface heat flux and temperature dependent thermo-physical properties using by heat input as parameter. Also, cut-off temperature of residual stress estimation by thermo-elastic analysis is determined. The fillet weldment were measured to determined their residual stress distributions for using hole-drilling method. As result, it was found that large tensile residual stress is about material yield strength, and the numerical simulation results for finite element method similar to residual stresses by hole-drilling method and other exiting research. Also, cut-off temperature is effectively determined by temperature which calculated maximum thermal stress equal to material yield strength.

• Journal of Korean Academy of Nursing
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• v.36 no.7
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• pp.1123-1134
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• 2006

Purpose: The purpose of this study was to identify the effects of aromatherapy on blood pressure and stress responses of clients with essential hypertension. Method: There were fifty-two subjects divided into an essential oil group, placebo group, and control group by random assignment. The application of aromatherapy was the inhalation method of blending oils with lavender, ylangylang, and bergamot once daily for 4 weeks. To evaluate the effects of aromatherapy, blood pressure and pulse were measured two times a week and serum cortisol levels, catecholamine levels, subjective stress, and state anxiety were measured before and after treatment in the three groups. Data was analyzed by repeated measures of ANOVA, one-way ANOVA, and $X^2-test$ using the SPSS 10.0 program. Results: The blood pressure, pulse, subjective stress, state anxiety, and serum cortisol levels among the three groups were significantly statistically different. The differences of catecholamine among the three groups were not significant statistically Conclusion: The results suggest that the inhalation method using essential oils can be considered an effective nursing intervention that reduces psychological stress responses and serum cortisol levels, as well as the blood pressure of clients with essential hypertension.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.6
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• pp.1784-1797
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• 1996

The disk/blade assembly of a turbine engine is made in the shape of a dovetail type or a fir-tree type. Since disk fillet regions or contact surfaces undergo high stress comcentration, fatigue cracks frequentrly occur in the disk/blade assembly. Therefore, it is necessary to analyze the stress distributions in the fir-tree type disk/balde assembly and predict the region of fatigue failure. The stress distributions of the disk/blade assembly were investigated by using the photoelastic method and the finite element method. Two dimensional photoelastic techniques were used to investigate the stress distributions of contact surfaces and fillet regions. TH stress distributions were obtained by the shear-difference method and were compared to the finite element results. It was found that maximum tensile stresses were higher in the fillet region thatn in the contact surfaces of the fir-tree models. The finite element results showed good agreement with the experimental results.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.10
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• pp.2398-2406
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• 1993

Abdi's numerical method(ref.13) for representing a stress singularity by shifting the mid-side nodes of isoparametric elements is reviewed. A simple technique to obtain the optimal position of the mid-side nodes in quadratic isoparametric finite element is presented. From this technique we can directly obtain the position of the side-nodes adjacent to the crack tip. It is also observed that the present technique provides good accuracy for the expression of the opening displacement and the determination of the mid-side nodes for more wide range of material properties than that obtained by Abdicant the finite element method is applied to determine stress intensity factors for pressurized crack perpendicular to and terminating at the interface of two bonded dissimilar materials. A proper definition for stress intensity factors of a crack perpendicular to bimaterial interface is provided. It is based upon a near-tip displacement solutions on the crack surface for interface crack between two dissimilar materials. Numerical testing is carried out with the eight-node and six-node elements. The results obtained are compared with the previous solutions.

• Journal of Korean society of Dental Hygiene
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• v.3 no.2
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• pp.101-116
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• 2003

The purpose of this study was to identify the personality type and stress coping method of students of Dept. dental hygiene students and relationship between them. Second purpose of this study was to suggest the good and useful method of stress coping. Data was drawn from a convenient sample of 350 and 3rd year students of the department of dental hygiene, some college located in Kyung-Ki Province. The results were analyzed with SPSS 10.0 and the conclusion is as follow: 1. The average of Machiavellism type is 3.30, which indicates that most of the students has a middle type(80%). In the A/B type, most of the students has B type(46.7%). In the score of externality and internality, externality(62.6%) is higher than internality(20.3%) 2. As a result of investigating how they coped with stress, the direct coping was utilized most and the physical was utilized least. 3. In the relation between the personality type and stress coping method, non-Machiavellism type has a statistically significant difference, in the direct coping and destructive coping.

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.625-631
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• 2006

Residual stresses in structural materials are stresses that exist in the objective without the application of any service or other external loads. Manufacturing processes are the most common causes of residual stress. To examine the effect and the distribution of residual stress due to press forming and welding in the production of a 600MPa-class steel tube, a residual stress evaluation test was performed. The measurement used the Hole-Drilling Strain Gauge Method and evaluated the distribution of residual stress, which measured a total of 59 places near the welding line.

• Computers and Concrete
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• v.12 no.4
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• pp.499-518
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• 2013

Fiber reinforced polymer (FRP) jackets have been widely used as an effective tool for the strengthening and rehabilitation of concrete structures, especially damaged concrete columns. Therefore, a clear understanding of the compressive behavior of FRP-confined concrete is essential. The objective of this paper is to develop a simple efficient method for predicting the compressive strength, the axial strain at the peak stress, and the stress-strain relationship of FRP-confined concrete. In this method, a compressive strength model is established based on Jefferson's failure surface. With the proposed strength model, the strength of FRP-confined concrete can be estimated more precisely. The axial strain at the peak stress is then evaluated using a damage-based formula. Finally, a modified stress-strain relationship is derived based on Lam and Teng's model. The validity of the proposed compressive strength and strain models and the modified stress-strain relationship is verified with a wide range of experimental results collected from the research literature and obtained from the self-conducted test. It can be concluded that, as a competitive alternative, the proposed method can be used to predict the compressive behavior of FRP-confined concrete with reasonable accuracy.