• Structural Engineering and Mechanics
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• v.8 no.2
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• pp.119-136
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• 1999

The failure load of a continuous prestressed concrete beam depends partially on the amount of redistribution of moment that occurs prior to failure. Results from a parametric study, carried out using a nonlinear finite element computer program, are presented to demonstrate the influences of various factors on redistribution of moment in two-span, continuous bonded prestressed concrete beams. Trends in the data from the numerical studies are compared with those from a theoretical expression for percentage of redistribution, and it is shown that the redistribution of moment occurring in a continuous prestressed concrete beam is a function of number of parameters.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.249-252
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• 1991

A Retrospective study to analyze the failure pattern in locally advanced stomach cancer, treated with radical surgery and post-op chemotherapy was perfomed. Among 107 patients who underwent radical gastrectomy in Asan Medical Center between June 1989 and August 1990. there were 20 stage II(T2NO, T2N1) and 87 stage III(T3N1, T3N2) and 91 patients were eligible for study. 57 patients treated with 6 cycles of postop adjuvant chemotherapy. Among 57 patients treated with postop adjuvant chemotherapy, local failure occurred in $21\%$ and distant failure in $12\%$. Among 34 patients who were not treated with postop chemotherapy, local failure occurred in $24\%$ and distant failure in $26\%$. Among 29 failures including 13 locoregional, 9 distant metastasis and 7 locoregional and distant metastasis, 11 cases recurred in the anastomotic site, 3 in the gastric bed,7 in the regional lymph nodes and peritoneal seeding occurred in 6 cases. The true incidences of gastric bed, nodal and peritoneal failures may be higher in the longer follow-up or reoperative or autopsy series. Our data sugest that postop chemocherapy is beneficial by reducing distant failure rate. Our data suggest that postop chemocherapy is beneficial by reducing distant failure rate. Postop adjuvant locoregional radiotherapy in addition to the systemic adjuvant therapy may reduce the local failure rate and potentially benefit in at least $20\%$ of patients who developed the local failure only.

• Journal of Chest Surgery
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• v.22 no.6
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• pp.951-959
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• 1989

Between September, 1972 and September, 1989, total 359 patients were operated for acquired heart disease at Department of Thoracic and Cardiovascular Surgery, Hanyang University Hospital. A consecutive series of 293 prosthetic valve replacement was also performed during this period. The results were summarized as follows; 1. There were 141 men and 218 women, whose ages ranged from 6 to 64 years, [mean 35.5 years] 2. Out of 293 cases, mitral valve replacement was 182 cases, aortic valve replacement was 39 cases and double valve replacement was70 cases. 3. Early post-operative death was 30 cases [Mortality; 8.4 %] and late death was 9 cases in the survivors. 4. Re-operation was 30 cases and operative mortality was 10%. 5. Mean post-operative interval was 76 months. [Ranged from 216 months to 2 months] 6. Among re-operation cases, primary prosthetic valve failure was 16 cases and paravalvular leakage was 2 cases. 7. Since January 1988, 79 cases of prosthetic valve replacement were performed and then 1 case was expired. [Mortality; 1.2 %]

• Steel and Composite Structures
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• v.18 no.2
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• pp.325-344
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• 2015

Experimental tests on cellular beams with sinusoidal openings showed two main failure modes around the openings. They concern the formation of four plastic hinges and the local instability of the sinusoidal part of the opening. In parallel, numerical analysis of the sinusoidal part of the opening revealed the existence of an elastic rotational restraint between the intermediate web-post and the adjacent opening panel. The aim of the present study is to present an approach to quantify this rotational restraint. Through the response surface method, a mathematical model is proposed. It shows a great ability to predict the rotational restraint value as a function of the geometrical parameters of the opening. This model can be used to perform an extensive study with various geometrical configurations of beams with the aim to develop a reliable and realistic analytical model predicting the resistance of the sinusoidal openings.

• Computers and Concrete
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• v.3 no.1
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• pp.65-77
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• 2006

This study reports the details of the finite element analysis of eleven shear critical partially prestressed concrete T-beams having steel fibers over partial or full depth. Prestressed concrete T-beams having a shear span to depth ratio of 2.65 and 1.59 and failing in the shear have been analyzed using 'ANSYS'. The 'ANSYS' model accounts for the nonlinear phenomenon, such as, bond-slip of longitudinal reinforcements, post-cracking tensile stiffness of the concrete, stress transfer across the cracked blocks of the concrete and load sustenance through the bridging of steel fibers at crack interface. The concrete is modeled using 'SOLID65'-eight-node brick element, which is capable of simulating the cracking and crushing behavior of brittle materials. The reinforcements such as deformed bars, prestressing wires and steel fibers have been modeled discretely using 'LINK8' - 3D spar element. The slip between the reinforcement (rebar, fibers) and the concrete has been modeled using a 'COMBIN39'-non-linear spring element connecting the nodes of the 'LINK8' element representing the reinforcement and nodes of the 'SOLID65' elements representing the concrete. The 'ANSYS' model correctly predicted the diagonal tension failure and shear compression failure of prestressed concrete beams observed in the experiment. The capability of the model to capture the critical crack regions, loads and deflections for various types of shear failures in prestressed concrete beam has been illustrated.

• International Journal of Heart Failure
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• v.6 no.3
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• pp.129-136
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• 2024

Background and Objectives: Heart failure (HF) is a leading cause of hospitalization and death worldwide. The Steady Movement with Innovating Leadership for Heart Failure (SMILE HF) aims to evaluate the clinical characteristics, management, hospital course, and long-term outcomes of patients hospitalized for acute HF in South Korea. Methods: This prospective, observational multicenter cohort study was conducted on consecutive patients hospitalized for acute HF in nine university hospitals since September 2019. Enrolment of 2000 patients should be completed in 2024, and follow-up is planned through 2025. Results: Interim analysis of 1,052 consecutive patients was performed to understand the baseline characteristics. The mean age was 69±15 years; 57.6% were male. The mean left ventricular ejection fraction was 39±15%. The prevalences of HF with reduced ejection fraction, HF with mildly reduced ejection fraction, and HF with preserved ejection fraction were 50.9%, 15.3%, and 29.2%. Ischemic cardiomyopathy (CMP) was the most common etiology (32%), followed by tachycardia-induced CMP (12.8%) and idiopathic dilated CMP (9.5%). The prescription rate of angiotensin-converting enzyme inhibitor/angiotensin receptor blockers/angiotensin receptor/neprilysin inhibitor, beta-blockers, spironolactone, and sodium-glucose cotransporter-2 inhibitors at discharge were 76.8%, 66.5%, 50.0%, and 17.5%, respectively. The post-discharge 90-day mortality and readmission rates due to HF aggravation were 2.0% and 6.4%, respectively. Our analysis reveals the current state of acute HF in South Korea. Conclusions: Our interim analysis provides valuable insights into the clinical characteristics, management, and early outcomes of acute HF patients in South Korea, highlighting the current state and treatment patterns in this population.

• Steel and Composite Structures
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• v.32 no.2
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• pp.265-279
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• 2019

The self-centering capacity and energy dissipation performance have been recognized critically for increasing the seismic performance of structures. This paper presents an innovative steel moment frame with self-centering steel reinforced concrete (SRC) wall panel incorporating replaceable energy dissipation devices (SF-SCWD). The self-centering mechanism and energy dissipation mechanism of the structure were validated by cyclic tests. The earthquake resilience of wall panel has the ability to limit structural damage and residual drift, while the energy dissipation devices located at wall toes are used to dissipate energy and reduce the seismic response. The oriented post-tensioned strands provide additional overturning force resistance and help to reduce residual drift. The main parameters were studied by numerical analysis to understand the complex structural behavior of this new system, such as initial stress of post-tensioning strands, yield strength of damper plates and height-width ratio of the wall panel. The static push-over analysis was conducted to investigate the failure process of the SF-SCWD. Moreover, nonlinear time history analysis of the 6-story frame was carried out, which confirmed the availability of the proposed structures in permanent drift mitigation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1649-1654
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• 2014

Background: Clinically significant portal hypertension (PHT) is considered as a contraindication for hepatectomy according to the guidelines of the European Association for Study of Liver and the American Association for Study of Liver Diseases. However, this issue remains controversial. Here we performed a metaanalysis to evaluate the impact of PHT on the results of hepatectomy for hepatocellular carcinoma (HCC). Methods: Cohort studies evaluating the impact of clinically significant PHT, defined as oesophageal varices and/or splenomegaly associated with thrombocytopenia, on the results of hepatectomy for HCC were identified using a predefined search strategy. Summary risk ratios (RRs) and 95% confidence intervals (95% CIs) for PHT and outcomes after hepatectomy for HCC were calculated. Results: Seven cohort studies which including 574 cases with PHT and 1,354 cases without PHT were considered eligible for inclusion. The meta-analysis showed that, in all patients, pooled RRs of post-operative liver failure, post-operative ascites, peri-operative blood transfusion, operative mortality, 3- and 5-year overall survival associated with PHT were 2.23 (95% CI: 1.48-3.34, P=0.0001), 1.77 (95% CI: 1.19-2.64, P=0.005), 1.23 (95% CI: 1.03-1.49, P=0.03), 2.58 (95% CI: 1.12-5.96, P=0.03), 0.82 (95% CI: 0.75-0.88, P<0.00001) and 0.76 (95% CI: 0.69-0.85, P<0.00001), respectively. In subgroup analysis, similar results were found in Child-Pugh class A patients. Conclusion: This meta-analysis suggests that presence of oesophageal varices and/or splenomegaly associated with thrombocytopenia is associated with higher rates of post-operative complications and poor long-term survival after hepatectomy for HCC.

• Geotechnical Engineering
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• v.13 no.3
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• pp.21-32
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• 1997

In this paper, an enhanced finite element model based on homogenisation technique is proposed to capture the localized failure mode of the intact rock masses. For this, bifurcation analysis at the element level is performed and, once the bifurcation is detected, equivalent material properties of the shear band and neighbouring intact rock are used to trace the post -peak behaviour of the material. It is demonstrated that mesh sensitivity of the strain softening model is overcome and progressive failure mode of rock specimen can be simulated relaistically. Furthermore, the numerical results show that the crack propagation and final failure mode can be captured with relatively coarse meshes and compares well with the experimental data available.

• Journal of the Korean Institute of Gas
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• v.10 no.1 s.30
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• pp.1-6
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• 2006

To use pressurized facilities safely and effectively, a likelihood of failure (LOF) for the brittle fracture was analyzed quantitatively through the risk based inspection using API-581 BRD. We found that for the case of the low temperature/low toughness and the temper embrittlement, the technical module subfactor (TMSF) showed high value for the A impact curve, low temperature, and the no post weld heat treatment. But the risk didn't significantly change at the $855^{\circ}F$ embrittlement, and the LOF far the sigma phase embrittlement showed high value at low temperature of the high sigma.