• Journal of Welding and Joining
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• 제21권5호
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• pp.547-554
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• 2003

Apparent mechanical properties in structural components can be different from the initially designed values due to the formation of the residual stress in metal forming and welding. Therefore, the evaluation of residual stress has great importance in the reliability diagnosis of structural components. A nondestructive instrumented indentation technique has been proposed to evaluate various strength concerning mechanical properties from the analysis of load-depth curve. In this study, quantitative residual stress estimation on API X65 welded joints for natural gas pipeline was performed by analyzing the variation of indentation loading curve by residual stress through a new proposed theoretical model. The residual stress from the indentation method was compared with that from the saw-cutting method.

• Journal of Welding and Joining
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• 제19권3호
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• pp.317-324
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• 2001

This study deals with high power Nd:YAG laser welding of thin steels for small pressure vessels. Full penetration welding at the overlap joint was performed so as to assure sufficient weld strength. Results showed that mid-depth weld size reduced drastically with increasing the travel speed. Position of focus had little effect on the bead formation even though short focal system was used. However, the shape factor and the bead width had closely related with the position of focus. Based on the microstructural inspection, acceptable weld was obtained when the overlap clearance was controlled up to 20% of the base metal thickness. In the case that the joint contained more clearance than the critical value, both the tensile shear strength and the tear strength were reduced. Results also demonstrated that shielding gases were proved to play a key role as far as the bead formation characteristics was taken into consideration. Blowing dry air through 5mm in diameter nozzle produced narrower bead cross-section than that of argon or nitrogen shielding.

• 근관절건강학회지
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• 제15권2호
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• pp.140-154
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• 2008

Purpose: The purpose of this study was to describe the adjustment process of patients with Amyotrophic Lateral Sclerosis(ALS). Method: The data were collected from May 2007 to February 2008 through individual in-depth interviews with 4 ALS patients. The data collection and analysis were performed according to grounded theory methodology, as suggested by Strauss and Corbin. Results: 'Accepting the sick role' was the central phenomenon, which was derived from 'perceiving an intial symptom'. Therefore, the adjustment pattern was represented by using the different strategies, which were 'raising hope' and 'hoping to dye comfortably'. For taking a view of the future, ALS patients adopted the strategies of 'living positively', 'being treated hardly', 'joining in the experience', 'depending on the absolute being', 'recognizing the dying process'. Conclusion: This study provides guidance for the development of nursing interventions for patients with ALS.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 가을 학술발표회 논문집
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• pp.51-56
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• 1990

Six small-scale reinforced concrete beam-column joint specimens subjected to monotonic and cyclic loading were tested to investigate the effects of strength of concrete. Variables are 1)compressive strength of concrete(f' c=300, 700kg/㎠), 2)shear span to depth ratio (a/d=4.7, 2.0). The major results of this test were: 1)flexural strength of high strength concrete beam-column joint was not affected too much by the compressive strength of concrete, 2) flexural cracks emerge to inside of beam deeply for high strength concrete member.

• 국제초고층학회논문집
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• 제11권3호
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• pp.189-196
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• 2022

The practical difficulties of construction will impose many restrictions on the structural design, and the construction method can also provide unexpected ideas for solving design problems. Through the discussion of three issues closely related to construction in the structural design of Wuhan Center, this paper illustrates the importance of in-depth consideration of the construction situations in the structural design stage. The topics of "Connection between Embedded Steel Plates in Steel Plate Composite Shear Wall" and "Connection Joint between Outrigger Truss and Core Wall" are about how to facilitate on-site construction by simplifying and optimizing detail design. The topic of "Adjusting Internal Force Distribution by Optimizing Construction Sequence" is about how to make the construction process a tool for structural design.

• 근관절건강학회지
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• 제30권2호
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• pp.59-69
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• 2023

Purpose: This study aimed to explore the experience of Fracture Liaison Service (FLS) coordinator nurses in a hospital setting. Methods: An in-depth interview was done using a semi-structured questionnaire on 4 FLS coordinator nurses between August 2022 and May 2023. A qualitative content analysis method was used for the data analysis. Results: Three themes of the experience of FLS coordinator were "The absence of identity of FLS coordinator," "struggling with the approach of creating something out of nothing," and "improvement of training and system to establish FLS coordinator role." Conclusion: This study identified three themes about the experience of FLS coordinator nurses in hospital setting. This finding is expected to be useful in developing education programs for FLS coordinator nurses.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.869-874
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• 2005

Given the intense competition and slowdown in domestic demands, there is greater pressure on Singapore contractors to seek overseas markets for revenue and growth. This impetus, coupled with emerging economic reforms in the regional developing countries, has invariably created numerous opportunities for Singapore contractors. However, mixed results were reported on their overseas performance so far. Consequently, this paper aims to formulate a framework that would assist Singapore contractors to successfully export their services into developing countries. The proposed framework comprises ten critical success factors (CSFs), which are identified from in-depth interviews with eight Singapore contractors. These ten success factors are subsequently classified under three different stages, namely initial, entry and operational stages. Preliminary results show that Singapore contractors are most focused on the entry stage, with the highest number of CSFs.

• 근관절건강학회지
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• 제30권3호
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• pp.168-178
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• 2023

Purpose: This study explored obstetric and neonatal nurses' nursing experience of pregnancy and childbirth in unmarried mothers. Methods: In-depth interviews were conducted with 12 nurses working in obstetrics, gynecology, and neonatal departments in Seoul and Busan. The collected data were examined using qualitative content analysis. Results: A total of four categories and ten themes were derived. The four categories were "Feelings toward unmarried mothers," "Difficulties faced when caring for unmarried mothers", "Nursing moving forward together", and "Strategies to improve care for unmarried mothers". Conclusion: To ensure that nurses can provide sufficient positive support and care when caring for unmarried mothers, healthcare workers must be provided with adequate education to improve their awareness and the services for unmarried mothers; in addition, interventions are needed to alleviate negative experiences and emotions when dealing with unmarried mothers.

• 대한기계학회논문집A
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• 제28권10호
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• pp.1549-1557
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• 2004

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

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1774-1779
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• 2005

Most of materials receive force in using, therefore, the characteristics of materials must be considered in system design not to occur deformation or destruction. Mechanical properties about materials can be expressed as responsible level of material itself under the exterior operation. Main mechanical properties is strength, hardness, ductility and stiffness etc. Currently, among major measure facilities to measure such mechanical properties, advanced indentation technique has focused in industrial areas as reason of nondestructive and easy applications for mechanical tensile properties and evaluation of residual stress of materials. This study is to find the optimum experimental condition about residual stress advanced indentation technique for accurate analysis of the welded joint of steel materials through indentation load-depth curve obtained from cruciform specimen experiment. Optimum selection was applied to the welded joint of real steel materials to give non-equi-biaxial stress state and compared with general residual stress analyzing method for verification.