• Steel and Composite Structures
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• v.43 no.4
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• pp.465-481
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• 2022

This paper presents a comprehensive integrity assessment of welded structural components, including uniform high- and low-cycle fatigue assessment of welded plate joints and fatigue-induced fracture assessment of welded plate joints. This study reports a series of fatigue and fracture tests of welded plate joints under three-point bending. To unify the assessment protocol for high- and low-cycle fatigue of welded plate joints, this study develops a numerical damage assessment framework for both high- and low-cycle fatigue. The calibrated damage material parameters are validated through the smooth coupon specimens. The proposed damage-based fatigue assessment approach describes, with reasonable accuracy, the total fatigue life of welded plate joints under high- and low-cycle fatigue actions. Subsequently, the study performs a tearing assessment on the ductile crack extension of the fatigue-induced crack. The tearing assessment diagram derives from the load-deformation curve of a single-edge notched bend, SE(B) specimen and successfully predicts the load-crack extension relation for the reported welded plate joints during the stable tearing process.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.646-655
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• 1990

A practically useful system for elastic-plastic fracture mechanics analysis has been developed. The developed system is comprised of the deformation plasticity failure assessment diagram(DPFAD) approach and the J-integral/Tearing modulus(J/T) approach. The system contains analysis routines for five types of fracture specimens : compact tension, center cracked tension, single edge craked plate in uniform tension, single edge cracked plate in three point bending and double edge cracked plate in tension. A double interpolation scheme was adopted to interpolate J values from the EPRI developed EPFM handbook and the Newton-Raphson method was used to obtain proper loadings for displacement control conditions. A graphic output system was utilized to present numerical results. Several case studies were performed to evaluate the accuracy and the usefulness of the code. It was found that the J/T approach and the DPFAD approach yielded similar results. However, the DPFAD approach is more convenient for qick assessment of integrity of cracked structures while the J/T approach is more useful in evaluating the full history of the fracture process.

• The Journal of Korean Physical Therapy
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• v.33 no.6
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• pp.304-306
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• 2021

Objectives: We report on a patient who showed mild bradykinesia due to injury of the corticofugal tract (CFT) from the secondary motor area following direct head trauma, which was demonstrated on diffusion tensor tractography (DTT). Case summary: A 58-year-old male patient underwent conservative management for subarachnoid hemorrhages caused by direct head trauma resulting from a fall from six-meter height at the department of neurosurgery of a local hospital. His Glasgow Coma Scale score was 3. He developed mildly slow movements following the head trauma and visited the rehabilitation department of a university hospital at ten weeks after the fall. The patient exhibited mild bradykinesia during walking and arm movements with mild weakness in all four extremities (G/G^-). Results: On ten-week DTT, narrowing of the right CFT from the supplementary motor area (SMA-CFT), and partial tearing of the left SMA-CFT, left CFTs from the dorsal premotor cortex (dPMC-CFT) and both corticospinal tracts (CSTs) at the subcortical white matter were observed. Conclusion: This case demonstrated abnormalities in both CSTs (partial tearing at the subcortical white matter and narrowing), both SMA-CFTs (narrowing and partial tearing) and left dPMC-CFT. We believe our findings suggest the necessity of assessment of the CFTs from the secondary motor area for patients with unexplained bradykinesia following direct head trauma.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.4
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• pp.491-501
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• 2021

This paper aims to evaluate the mechanical integrity for Spent Nuclear Fuel (SNF) cladding under lateral loads during transportation. The evaluation process requires a conservative consideration of the degradation conditions of SNF cladding, especially the hydride effect, which reduces the ductility of the cladding. The dynamic forces occurring during the drop event are pinch force, axial force and bending moment. Among those forces, axial force and bending moment can induce transverse tearing of cladding. Our assessment of 14 × 14 PWR SNF was performed using finite element analysis considering SNF characteristics. We also considered the probabilistic procedures with a Monte Carlo method and a reliability evaluation. The evaluation results revealed that there was no probability of damage under normal conditions, and that under accident conditions the probability was small for transverse failure mode.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.161-176
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• 1993

For the purpose of assessing structural integrity at a level of complexity and accuracy appropriate for the situation, integrity assessment methods are formulated with the following methods. One is three-tier assessment method of the revised BSI PD 6493 which considers stable crack growth effect, the others are limit load analysis which estimates the plastic collapse load and stability assessment method which considers stable crack growth of ductile material exactly using J-integral and tearing modulus. Besides, integrity assessments for center cracked panel(CCP) specimen and the circumferential through-cracked pipe are carried out and reliability analysis is accomplished by the first order reliability method which is one of the conventional reliability methods. Also the accuracy of the present method is verified by Monte Carlo method.

• Nuclear Engineering and Technology
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• v.31 no.3
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• pp.267-275
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• 1999

This paper deals with the industrial problem of thermal striping damage on the French prototype fast breeder reactor, Phenix and it was studied in coordination with the research program of IAEA. The thermomechanical and fracture mechanics evaluation procedure of thermal striping damage on the tee-junction of the secondary piping using Green's function method and standard FEM is presented. The thermohydraulic(T/H) loading condition used in the present analysis is the random type thermal loads computed by T/H analysis on the turbulent mixing of the two flows with different temperatures. The thermomechanical fatigue damage was evaluated according to ASME code section 111 subsection NH. The results of the fatigue analysis showed that fatigue failure would occur at the welded joint within 90,000 hours of operation. The assessment for the fracture behavior of the welded joint showed that the crack would be initiated at an early stage in the operation. It took 42,698.9 hours for the crack to propagate up to 5 mm along the thickness direction. After then, however, the instability analysis, using tearing modulus, showed that the crack would be arrested, which was in agreement with the actual observation of the crack. An efficient analysis procedure using Green's function approach for the crack propagation problem under random type load was proposed in this study. The analysis results showed good agreement with those of the practical observations.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4647-4658
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• 2023

In this paper, elastic-plastic fracture mechanics analysis is performed to determine the critical crack sizes of the multipurpose canister (MPC) manufactured using austenitic stainless steel under dynamic loading conditions that simulate drop accidents. Firstly, dynamic finite element (FE) analysis is performed using Abaqus v.2018 with the KORAD (Korea Radioactive Waste Agency)-21 model under two drop accident conditions. Through the FE analysis, critical locations and through-thickness stress distributions in the MPC are identified, where the maximum plastic strain occurs during impact loadings. Then, the evaluation using the failure assessment diagram (FAD) is performed by postulating an external surface crack at the critical location to determine the critical crack depth. It is found that, for the drop cases considered in this paper, the principal failure mechanism for the circumferential surface crack is found to be the plastic collapse due to dominant high bending axial stress in the thickness. For axial cracks, the plastic collapse is also the dominant failure mechanism due to high membrane hoop stress, followed by the ductile tearing analysis. When incorporating the strain rate effect on yield strength and fracture toughness, the critical crack depth increases from 10 to 20%.

• Journal of Arbitration Studies
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• v.30 no.3
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• pp.47-66
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• 2020

Due to the division of China's departmental laws, the disconnect between theory and practice, and the influence of traditional academic thinking on the understanding of the knowledge structure of arbitration legal talents in practice, the construction of law school colleges, teaching teams, and research centers mostly revolves around departmental laws, tearing the connection of the arbitration legal system. The student-centered, process-guaranteed, and result-oriented arbitration master of law training model is "virtualized," the shaping of arbitration professionalism is ignored, the coverage of practical teaching is narrowed, and the arbitration legal profession is mostly formalized. The prevalence of specialized curriculum systems shortage, single faculty, formalized practical teaching, outdated curriculum settings, unsuitable curriculum system design for development, and inaccurate professional curriculum standards and positioning renders it difficult to integrate the "Belt and Road." The cutting-edge, the latest research results, and practical experience cannot reflect the connotation, goals, and requirements of "Entrepreneurship" education, as well as arbitral issues such as the ineffective monitoring of practical education and the inconsistent evaluation of standards and scales. Under the background of the "Belt and Road," based on system theory and practice and through training goals that innovate and initiate organizational form, activity content, management characteristics, assessment and support conditions, etc., the arbitration law teaching curriculum system is gradually improved and integrated. Through the establishment of a "Belt and Road" arbitration case file database and other measures, a complete arbitration law theory and practice teaching guarantee system has been established. Third parties are introduced, arbitration law experimental modules are developed, students are guided how to discover new knowledge, new contents are mastered, solidarity, cooperation, and problem-solving capabilities are cultivated in the practice of the "Belt and Road," and quality education, vocational education, and innovation education are organically integrated. In order to implement the requirements of arbitration law education, innovation development and collaborative management of arbitration law teaching practice base should be cultivated, thus giving full play to the effect of collaborative education between universities and arbitration institutions.

• Journal of Acupuncture Research
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• v.28 no.2
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• pp.75-87
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• 2011

Objectives : The purpose of this study is research on facial palsy sequelae and evaluating scale that have studied insufficiently until now. Methods : We researched on the symptoms, epidemiology and evaluating scale of facial palsy sequelae. For this, we searched the research papers on facial palsy sequelae and the clinical papers that find out the effect of treatment by evaluating facial palsy sequelae. Results : The symptoms of facial palsy sequelae are synkinesis, contracture, spasm, crocodile tears syndrome, tearing decrease, gustation impairment, hearing impairment, tinnitus, hyperacusis, etc. Among these, synkinesis, contracture, spasm and crocodile tears syndrome are the most frequently observed broadly. The poor prognosis factor of facial palsy can be the risk factor of facial palsy sequelae. For example, severe degeneration of facial nerve can be the risk factor of facial palsy sequelae. Most of clinical papers on facial palsy sequelae have used NRS(numeric rating scale) as evaluating scale. But NRS is very subjective scale. The scales of Stennert, Peitersen, Murata et al. can evaluate facial palsy sequelae grossly. Sunnybrook scale, Sydney scale, SAQ(synkinesis assessment questionnaire), the scale of Kim, the scale of Scott, HFS-7(hemi facial spasm), HFS-36 and Schirmer's test can evaluate the respective symptoms of facial palsy sequelae. Conclusions : The symptoms of facial palsy sequelae are synkinesis, contracture, spasm, crocodile tears syndrome, etc. Most of clinical papers on facial palsy sequelae have used NRS as evaluating scale. There were some scales that can evaluate facial palsy sequelae grossly and respectively. In future, we will need more progressed study of facial palsy sequelae and evaluating scale.