• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제6권2호
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• pp.192-196
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• 2003

Angiodysplasia is the most common vascular abnormality of the gastrointestinal tract and probably the most frequent cause of recurrent lower intestinal bleeding in otherwise healthy elderly patients. Also, it is an important cause of hemorrhage in chronic renal failure observed in up to 19~32% of patients. Bleeding due to gastric angiodysplasia is treated by various endoscopic approaches, including argon and Nd : YAG laser photocoagulation, monopolar or bipolar electrocoagulation, heater probe, injection sclerotherapy, band ligation or hemoclipping. A 15-year-old boy, who had undergone hemodialysis for chronic renal failure for about 10 years, was admitted due to melena and progressive anemia. A gastroduodenoscopy revealed a cherry red and fern-like lesion with oozing on the posterior wall at junction of gastric body and fundus. Endoscopic hemoclipping therapy was performed. However, melena recurred four days later. Argon plasma coagulation and hemoclipping therapy were performed again. Since then, no recurrence of bleeding has been observed.

• Wind and Structures
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• 제10권3호
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• pp.269-285
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• 2007

This paper assesses the damage to high-set rectangular-plan houses with low-pitch gable roofs (built in the 1960 and 70s in the northern parts of Australia) to wind speeds experienced in tropical cyclones. The study estimates the likely failure mode and percentage of failure for a representative proportion of houses with increasing wind speed. Structural reliability concepts are used to determine the levels of damage. The wind load and the component connection strengths are treated as random variables with log-normal distributions. These variables are derived from experiments, structural analysis, damage investigations and experience. This study also incorporates progressive failures and considers the inter-dependency between the structural components in the house, when estimating the types and percentages of the overall failures in the population of these houses. The progressively increasing percentage of houses being subjected to high internal pressures resulting from damage to the envelope is considered. Results from this study also compare favourably with levels of damage and related modes of failure for high-set houses observed in post-cyclone damage surveys.

• Computers and Concrete
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• 제25권4호
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• pp.293-302
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• 2020

Connections play a significant role in strength of structures against earthquake-induced loads. According to the post-seismic reports, connection failure is a cause of overall failure in reinforced concrete (RC) structures. Connection failure results in a sudden increase in inter-story drift, followed by early and progressive failure across the entire structure. This article investigated the cyclic performance and behavioral improvement of shape-memory alloy-based connections (SMA-based connections). The novelty of the present work is focused on the effect of shape memory alloy bars is damage reduction, strain recoverability, and cracking distribution of the stated material in RC moment frames under seismic loads using 3D nonlinear static analyses. The present numerical study was verified using two experimental connections. Then, the performance of connections was studied using 14 models with different reinforcement details on a scale of 3:4. The response parameters under study included moment-rotation, secant stiffness, energy dissipation, strain of bar, and moment-curvature of the connection. The connections were simulated using LS-DYNA environment. The models with longitudinal SMA-based bars, as the main bars, could eliminate residual plastic rotations and thus reduce the demand for post-earthquake structural repairs. The flag-shaped stress-strain curve of SMA-based materials resulted in a very slight residual drift in such connections.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.431.2-432
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• 2002

Mucopolysaccharidosis (MPS) is a genetic disorder with deficiency of Iysomal enzymes needed for the degradation of glycosaminoglycans(GAGs). This storage disease is characterized by intra-lysosomal accumulation of GAGs. progressive mental and physical deterioration. multi-organ failure and premature death. Quality of life (QOL) is very low in MPS patients. The MOS 36-ltem Short Form Health Survey (SF-36) was designed to measure the eight (8) dimensions of health in clinical and general population settings. (omitted)

• Communications for Statistical Applications and Methods
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• 제17권1호
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• pp.99-106
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• 2010

In this paper, we present two methods for obtaining prediction intervals for the times to failure of units censored in multiple stages in a progressively censored sample from proportional hazard rate models. A numerical example and a Monte Carlo simulation study are presented to illustrate the prediction methods.

• 한국임상수의학회지
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• 제19권4호
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• pp.411-414
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• 2002

Eighty five canine eyes performed phacoemulsification for cataract extraction between January 1999 and December 2001 were reviewed. Mean age was 7.26 years old and main breed was poodle (37 dogs). Mature cataract was 51.76％, immature cataract 27.05% and hypermature 21.18％. Improvement of vision was detected in 75 (88.24%) of 85 eyes at 4 weeks after surgery. Postoperative complications were posterior capsular opacification(6), partial posterior synechia(5), glaucoma(3) and uveitis(2). Reasons for failure of visual improvement among the patients performed phacoemulsification were mainly related to development of postoperative anterior uveitis, secondary glaucoma and progressive retinal degeneration.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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• pp.288-291
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• 2004

The characteristics of the buckling analysis module for stiffened composite structures were studied in this paper. Composite stiffened structures have geometrical asymmetry and material properties asymmetry. Due to these reason, postbuckling analysis was essential and the characteristics of postbuckling analysis modules for ABAQUS were researched. Static analysis module was considered. By considering the material nonlinearity, progressive failure mechanism was applied and buckling strength was estimated

• Geomechanics and Engineering
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• 제30권5호
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• pp.401-411
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• 2022

To obtain the dynamic mechanical properties, fracture modes, energy and brittleness characteristics of Furong Baijiao coal rock, the dynamic impact compression tests under 0, 4, 8 and 12 MPa confining pressure were carried out using the split Hopkinson pressure bar. The results show that failure mode of coal rock in uniaxial state is axial splitting failure, while it is mainly compression-shear failure with tensile failure in triaxial state. With strain rate and confining pressure increasing, compressive strength and peak strain increase, average fragmentation increases and fractal dimension decreases. Based on energy dissipation theory, the dissipated energy density of coal rock increases gradually with growing confining pressure, but it has little correlation with strain rate. Considering progressive destruction process of coal rock, damage variable was defined as the ratio of dissipated energy density to total absorbed energy density. The maximum damage rate was obtained by deriving damage variable to reflect its maximum failure severity, then a brittleness index BD was established based on the maximum damage rate. BD value declined gradually as confining pressure and strain rate increase, indicating the decrease of brittleness and destruction degree. When confining pressure rises to 12 MPa, brittleness index and average fragmentation gradually stabilize, which shows confining pressure growing cannot cause continuous damage. Finally, integrating dynamic deformation and destruction process of coal rock and according to its final failure characteristics under different confining pressures, BD value is used to classify the brittleness into four grades.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 춘계학술발표대회 논문집
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• pp.211-214
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• 2000

Filament wound pressure vessels have been studied for the efficient design tool to consider the variation of fiber angles through-the thickness direction. Filament winding patterns were simulated from semi-geodesic fiber path equation to calculate fiber path on arbitrary surface. Finite element analyses were performed considering fiber angle variation in longitudinal and thickness directions by ABAQUS. For the finite element modeling of the pressure tank, the 3-dimensional layered solid element was utilized. From the stress results of pressure tanks, maximum stress criterion in transverse direction was applied to modify material properties for failed region. In the end of each load increment, resultant layer stresses were compared with a failure criterion and properties were reduced to 1/10 for a failed layer. Results of progressive failure analysis were compared with two experimental data.

• 대한기계학회논문집
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• 제17권8호
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• pp.2051-2060
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• 1993

A finite element program using degenerated shell element was developed to solve the geometric, material and combined nonlinear behaviors of composite laminated shell. The total Lagrangian method was implemented for geometric nonlinear analysis. The material nonlinear behavior was analyzed by considering the matrix degradation due to the progressive failure in the matrix and matrix-fiber interface after initial failure. The result of the geometric nonlinear analysis showed good agreement with the other exact and numerical solutions. The results of the combined analyses considered both geometric and material nonlinear analyses were compared with the experiments in which internal pressure was applied to the filament wound antisymmetric tubes.