• Proceedings of the KSME Conference
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• 2004.04a
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• pp.120-125
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• 2004

Fatigue life of welded joints are governed by the propagation of multiple collinear surface cracks distributed randomly along weld bead. These cracks propagate in mutual interaction and coalescence of them. To estimate the fatigue life, the influences of above two mechanisms on the fatigue life should be taken into account. These two mechanisms appear through the stress intensity factors disturbed mutually. However, it is difficult to calculate the stress intensity factors of multiple surface cracks located in vicinity of weld toe. The stress intensity factors are calculated normally by using the Mk-factors, but such Mk-factors are very rare in literature. In this study, the Mk-factors were obtained from a parametric study on crack length and depth, in which a finite element method is used. A fatigue test for a cruciform welded joint was conducted. The fatigue life of the tested specimen was estimated through present method with the informations obtained from the test, e.g. the number, size and locations of the cracks. The estimated and measured fatigue life showed a good agreement.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.655-659
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• 1997

The analysis of cracks at the interface between dissimilar materilar has received a great deal of attention in recent years. In this paper we conducted the static tensile test for the aluminum bonded single lap-joint with the interface edge crack. Comparing this results, that is ultimate load and strain value of aluminum adherend by strain gauge with the fracture mechanics parameters, compliance and stress intensity factors acquied from the boundary element analysis, we concluded that there are critical value of crack length to provoke the interface fracture.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.411-412
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• 2009

The techniques of testing and controlling intensity of structural concrete involve many problems and difficulties on the construction site. Hence this study aims at evaluating intensity of structural concrete in order to verify on-site application and structural efficiency assessment using joint separation test body.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.405-406
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• 2009

This study aims at evaluating and analyzing hydration property and intensity property of structural concrete and joint separation test body in order to test and control the intensity of structural concrete. It also aims at examining validity and the plan to make similar environment with structural concrete

• Journal of Welding and Joining
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• v.18 no.5
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• pp.33-40
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• 2000

Fatigue crack propagation life of weld toe crack through residual stress field was estimated with Elber's crack concept. Propagation of weld toe crack is heavily influenced by residual stress caused by welding process, so it is essential to take into account the effect of residual stress on the propagation life of weld toe crack. Fatigue crack at transverse and longitudinal weld toe was studied respectively, which represent typical weld joint in ship structure. Numerical and experimental studies are performed for both cases. Residual stress near weldment was estimated through nonlinear thermo-elasto-plastic finite element method, and residual stress intensity factor with Glinka's weight function method. Effective stress intensity factor was calculated with Newman-Forman-de Koning-Henriksen equation which is based on Dugdale strip yield model in estimating crack closure level U at different stress ratio. Calculated crack propagation life coincided well with experimental results.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.587-587
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• 1989

• Journal of Korean Academy of Nursing
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• v.18 no.2
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• pp.197-210
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• 1988

The purposes of this study were : 1) to assess the level of pain and to identity the varieties and the degree of pain-related behavior, 2) to measure the level of correlation between the level of pain and the degree of pain- related behavior, 3) to test the correlation between the Korean Pain Rating Scale (KPRS) and Graphic Rating Scale(GRS), and 4) to gather data relevant to the Socio-demographic status of the subjects. The level of pain was measured by KPRS and GRS developed by the researchers. The KPRS consists of three dimensions ; the sensory, the affective and the miscellaneous and the GRS of two separate scales ; the intensity scale and the unpleasantness scale. Of the 2, 025 who had visited orthopedic and neurosurgical out-patients department of 11 university hospitals in various districts of Korea with the episode of Joint pain, 405 subjects were self-selected by responding to the data gathering tools and questionaires mailed. The results are summaried as follows : 1. Maale(217, 53.6%) exceeded female patients(188, 46.4%) in number and the onset of joint pain was more prevalent in the age groups of the 20s and the 30s. 160(39.5%) had been hospitalized for the treatment of, and 87(21.5%) had retired because of the joint pain. 2. Mean pain score measured by KPRS was 128.31 (range; 0-1.344.8) ; mean sensory score was 43.23(range ; 0-645.88%), mean affective score was 46.09(range ; 0- 356.72), and mean miscellaneous score was 39.99(range ; 0-341.68). Mean pain scores measured by GRS were ; sensory intensity score ; 109.1(range ; 0-200) and distress score ; 99.1 (range ; 0-200). 3. The prevalent sites of joint pain revealed to be the right knee joint(203; 50.1%), left knee joint(181(44.7%), left ilium(147, 36.3%), lumbar region (106; 26.2%), hip joint(92; 22.7%) and the ankle(84; 20.7%). 4. The average sleep hour was 6.8hours per day and the average rest hour during the day hours was 3.3hours (range 0-20). 5. The average duration of suffering from joint pain was 49.1 months. 6. Most of the subjects(298; 73.6%) used some sorts of pain relieving practices ; the most prevalent pain relieving practice was the compliance with the physician prescribed treatments(34.4%). 7. The level of discomfort in carrying out the ADL(activities of daily living was 101.16(38.83) and the level of needs for aid in carrying out the ADL was 76.62(31.79). 8. The interrelation between KPRS total score and GRS sensory intensity score(.4438), as well as that of GRS distress score(r＝.4446) were not highly correlated, however, sensory and affective dimension within KPRS (.7547) and pain intensity and distress score of GRS(.6975) revealed moderate intercorrelation. 9. Pain-related behaviors such as discomfort in carrying out ADL, the need for aids in carrying out ADL, frequency of pain relieving practices, varieties of pain sites and length of rest hours during the day hours revealed to be highly correlated with the level of pain measured by KPRS, GRS sensory intensity scale and GRS distress scale. The following are recommended ; 1. Test for the correlation of KPRS total score and the summated score of GRS ; sensory intensity and distress scores. 2. Possibilities of utilization of the pain-related behaviors which revealed high correlation as indirect assessment tool for measuring the level of pain.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.20-27
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• 1998

According as the member of the automobile body structure have been thinned their thickness and have become high strength, each part of the body structure has been put more severe stress condition. And, because fatigue strength of the spot welded lap joint is influenced by its geometrical and mechanical factors, welding condition and etc., there needs a quantitative and systematic evaluation method for them. In this study, by considering nugget edge of the spot weld part of the IB-type spot welded lap joint under tension-shear load to the ligament crack. fatigue strength of various IB-type spot welded lap joints was estimated with the stress intensity factor(S.I.F.) KIII which is fracture mechanical parameter. We could find that fatigue strength evaluation of the IB-type spot welded lap joints by KIII is more effective than the maximum principal stress ($\sigma$1max) at edge of the spot weld obtained from FEM analysis.

• Journal of muscle and joint health
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• v.19 no.2
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• pp.173-183
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• 2012

Purpose: The purpose of this study was to analyze nursing records for pain management in intensive care unit (ICU) patients. Methods: Nursing process for pain management were analyzed retrospectively by 180 ICU patients' nursing records. Instruments consisted of 3 questionnaires (pain assessment, intervention, and evaluation). Results: For assessment, there was different pain intensity between cancer patients (7.95) and non-cancer patients (7.20). Also pain intensity was lower in PCA group (5.08) than in PCA with PRN group (8.27). Common pain site was surgical areas, along with 17 kinds of words expressed for pain, and mean of pain intensity was 7.47 by numeric rating scales (NRS). For intervention, the patients received pharmacologic interventions (99.4%) such as narcotic analgesics (38.3%) intermittently (70.5%) without side effects (94.4%). For evaluation, mean of pain intensity was decreased to 3.14, but a few patients (12.8%) experienced pain over 5 points despite the intervention. Nurses evaluated the degree of pain relief after the intervention in 87.2% of patients. Conclusion: Nurses do assess patients' pain by using objective tool, intervene, and evaluate for effective pain management. Nurses should make an individual approach and record all nursing activities for pain management.

• Journal of Welding and Joining
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• v.3 no.2
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• pp.52-63
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• 1985

Fillet welded joints, specially in ship structure, are well known the critical part where stress concentrate or crack initiates and grows. This paper is concerned with the study of the behavior of fatigue crack growth t the root and toe of load carrying cruciform fillet welded joints under three points bending by the determination of stress intensity factor from the J-Integral, using the Finite Element Method. The stress intensity factor was investigated in accordance to the variation of the weld size (H/Tp). weld penetration (a/W) and plate thickness (2a'/Tp). As mixed mode is occurred on account of shearing force under the three points bending, Stern's reciprocal theory is applied to confirm which mode is the major one. The main results may be summarized as follows 1) The calculation formula of the stress intensity factor at the both of root and toe of the joint was obtained to estimate the stress intensity factor in the arbitrary case. 2) The change of stress field around crack tip gives much influence on each other at the roof and toe as H/Tp decreases. 3) Mode I is a major mode under the three points bending.