• Proceedings of the KSME Conference
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• 2004.11a
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• pp.25-30
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• 2004

The magnitude of constraint effect $A_{2}$ values were experimentally estimated using displacement according to measuring positions on the non-linear elastic plastic fracture toughness estimate. For 25.4 mm thickness SS400 steel CT specimen, constraint effect $A_{2}$ values we re dependent on specimen configuration and on measured displacement near crack front. Commonly, Estimating constraint effect $A_{2}$ measuring position for displacement should be existed inside plastic region. Therefore, the ${\delta}_{5}$ method was not reliable for evaluation of constraint effect $A_{2}$ values because measuring position for displacement is in elastic region at crack growth initiation in this paper.

• Journal of the Society of Disaster Information
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• v.7 no.2
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• pp.161-171
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• 2011

This research puts the purpose in elucidating the effect of participation types of leisure activity and leisure restraints on life quality. To achieve research purpose, questionnaire survey was conducted on 200 subjects who are engaged in private guard companies with ages over 20. Using the collected data, frequency analysis was conducted in order to identify demographic characteristics with SPSS/WIN 17.0V program. In addition, multiple regression analysis was conducted for solving research questions. As a result, sports related participation type had a positive effect on time constraint factor. Meanwhile, hobby related participation type had a positive effect on time and cost constraint, participation type of watching has a positive effect on individual and social constraint. Tour and play related participation type had a positive effect on individual constraint factor. Meanwhile participation type of sociality had a positive effect on individual constraint and hobby factor, but had a negative effect on familial and social constraint. Sports related participation type had a positive effect on social relationship factor. Participation type of watching and play related participation type had a negative effect on family relationship. Finally, time constraint factor had a positive effect on family relationship, and cost constraint factor had a positive effect on entire quality of life. Individual and family constraint factors had a negative effect on leisure relationship factor. Also, social constraint factor had a positive effect on family relationship, but had a negative effect on leisure relationship.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.4
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• pp.533-538
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• 2009

The magnitude of constraint effect $A_2$ values on the non-linear elastic plastic fracture toughness was experimentally estimated by using displacement at various measuring positions near crack tip. Constraint effect $A_2$ value was dependent on specimen configuration and on the measured displacement near crack front. The crack tip opening displacement in the vicinity of the crack tip front should be estimated within plastic region when appropriately constraint effect was calculated. It was found that the magnitude of constrain effect |$A_2$| is below 8.0 at the crack tip. But an appropriate location to measure the effective constraint effects $A_2$ at the critical value of J that crack initiation is characterizable by is r = 2mm and ${\theta}=90^{\circ}$ away from original crack tip, and the constraint effect |$A_2$| estimated is 5.3.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.1
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• pp.71-76
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• 2019

Actual stress distributions in the nozzle of a pressure vessel may not be in plane strain condition, implying that the crack-tip constraint condition may be relaxed in the nozzle. In this paper, a methodology for evaluating the fracture toughness of the ASME Code is presented considering the relaxation of the constraint effect in the nozzle of the reactor pressure vessel. The crack-tip constraint effect is quantified by the T-stress. The equation, which represent the relation between the fracture toughness in the lower constraint condition and the plane strain fracture toughness, is derived using the T-stress. This equation is similar to the method for evaluating the fracture toughness of the Master Curve for low constraint conditions. As a result of evaluating the fracture toughness considering the constraint effect in the reactor inlet, outlet and direct injection nozzles using the proposed equation, it was confirmed that the fracture toughness in the nozzles is higher than the plane strain fracture toughness. Applying the proposed evaluation methodology, it is possible to reflect the relaxation of the constraint effect in the nozzles of the reactor pressure vessel, therefore, the safe operation area on the pressure-temperature limit curve can be prevented from being excessively limited.

• Management & Information Systems Review
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• v.35 no.1
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• pp.69-84
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• 2016

This study set the research model to examine the correlation between Word-of-Mouth constraint factors, efforts to negotiate pertaining to these, Flow and Word-of-Mouth intent based on the theory of leisure constrain when it comes to the correlation between consumers' Word-of-Mouth constraint factors and Word-of-Mouth. Correlation among the variables were verified in an empirical manner. Results of this study are summarized as follows. After verifying the hypotheses, all the hypotheses were adopted excluding the hypotheses of two results (Hypothesis 1, hypotheses 5). Detailed results regarding this are as follows. First, the following is the effect of the Intrapersonal Constraint and Word-of-Mouth constraint factors on the Word-of-Mouth constraint negotiation effort. Interpersonal Constraint and Structural Constraint exert positive (-) effect on the Word-of-Mouth constraint negotiation effort. In case of Intrapersonal Constraint, negative (-) effect was demonstrated. Thus, this was statistically significant although dismissed from hypothesis verification. Second, the following is the result of examining the structural correlation between Word-of-Mouth constraint negotiation effort, Flow and Word-of-Mouth. Word-of-Mouth constraint negotiation effort exerts positive (-) effect on the Flow, but it was not statistically effective in case of the Word-of-Mouth. Lastly, it is possible to see that the Flow plays the role of a medium since it exerted positive (-) effect on the Word-of-Mouth. Results of this study are expected to provide key theoretical and working level implications as well as general understanding of the Word-of-Mouth constraint factors, consumers' Flow and Word-of-Mouth.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.91-92
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• 2006

For the CT specimen of 25.4mm thickness SS400 steel, the fracture toughness and the magnitude of constraint effect, $A_2$ on the non-linear elastoplastic fracture behaviors were experimentally estimated by crack tip opening displacement. In order to estimate constraint effect, displacement measurement position near crack front should be the existed within plastic region. But it is found that the displacement measurement positions by the ${\delta}_5$ method are in elastic region at crack growth initiation. Hence the estimate of constraint effect, $A_2$ by the ${\delta}_5$ method was not reliable.

• Korean Journal of Metals and Materials
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• v.46 no.6
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• pp.345-350
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• 2008

The magnitude of constraint effect $A_2$ value was experimentally estimated by using crack tip opening displacement(CTOD) between elastic and plastic regions near crack tip front for CT specimen with $25.4t{\ss}{\AE}$ SS400 steel. The constraint effect, $A_2$ was dependent on specimen configuration and on the measured positions of CTOD near crack front. $A_2$ should be estimated using the opening displacement calculated within crack front plastic region. If not, it's not reliable to evaluate of constraint effect at crack growth initiation in this paper.

• Journal of Family Resource Management and Policy Review
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• v.9 no.1
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• pp.59-73
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• 2005

The purpose of this study was to understand which factors affect on the leisure constraint and leisure attitude of workers, to observe how the factors of leisure constraints affect on the leisure attitude. The subjects of this study were 267 urban workers who are older than 20 years old and resident in Seoul. The periods of this study was from November 15 to December 5. The modified versions of leisure constraint scale and leisure attitude scale were utilized for this study. The results of this study are as follows : First, as a result to compare the average of leisure constraint factors, intrapersonal constraint, which are individual mental status as interest, self-consciousness, uneasiness et at., was founded generally less than interpersonal constraints as personal relationship for leisure activity, or structural constraints as financial, time, information et at., Secondly, it was found that interpersonal constraint was statistically different in age, and that structural constraint was statistically different in sex, education, health status, marital status, income, and career. Thirdly, there were statistically different in cognitive leisure attitude, feeling leisure attitude, and behavioral leisure attitude according to the average monthly income and career. But, it was found that marital status and the five-day workweek system were not statistically different in 3 leisure attitude factors. Finally, 3 leisure constraint factors(intrapersonal, interpersonal, structural) had statistically significant effect on cognitive leisure attitude. Also, intrapersonal leisure constraint and interpersonal leisure constraint had statistically significant effect on feeling leisure attitude and behavioral leisure attitude

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1726-1746
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• 2022

This paper presents fracture mechanics analysis results for various cracks located at pressurized water reactor pressure vessel nozzle crotch corners taking into consideration constraint effect. Technical documents such as the ASME B&PV Code, Sec.XI were reviewed and then a fracture mechanics analysis procedure was proposed for structural integrity assessment of various nozzle crotch corner cracks under normal operation conditions considering the constraint effect. Linear elastic fracture mechanics analysis was performed by conducting finite element analysis with the proposed analysis procedure. Based on the evaluation results, elastic-plastic fracture mechanics analysis taking into account the constraint effect was performed only for the axial surface crack of the reactor pressure vessel outlet nozzle with cladding. The fracture mechanics analysis result shows that only the axial surface crack in the reactor pressure vessel outlet nozzle has the stress intensity factor exceeding the low bound of upper-shelf fracture toughness irrespectively of considering the constraint effect. It is confirmed that the J-integral for the axial crack of the outlet nozzle does not exceed the ductile crack initiation toughness. Hence, it can be ensured that the structural integrity of all the cracks is maintained during the normal operation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.1
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• pp.105-112
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• 2002

In recent years, the integrity of reactor Pressure Vessel(RPV) under pressurized thermal shock (PTS) accident has been treated as one of the most critical issues. Under PTS condition, the combination of thermal and mechanical stress by steep temperature gradient and internal pressure causes considerably high tensile stress at the inside of RPV wall. As a result, cracks on inner surface of RPV may experience elastic-plastic behavior which can be characterized by J-integral. In such a case, however, J-integral may possibly lose its vapidity due to the constraint effect. The degree of constraint effect is influenced by the loading mode, crack geometry and material properties. In this paper, in order to investigate the effect of clad thickness and crack geometry on constraint effect, three dimensional finite element analyses were performed for various surface cracks. Total of 27 crack geometries were analyzed and results were presented by a two-parameter characterization based on the J-integral and the f-stress.