• The Korean Journal of Pain
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• v.13 no.2
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• pp.237-241
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• 2000

Vertebral compression fractures commonly afflict the elderly. Some patients suffer from severe mechanical pain in spite of treatments with strong analgesics and bracing. Vertebroplasty, which was originally used for vertebral hemangioma, is effective for patients who do not respond to these more conservative treatments. However, the procedure has some risk. Leaks of bone cement into perineural tissues can be a serious complication. In contrast to the lumbar vertebrae, the outer margin of the pedicle of the thoracic vertebrae is almost in line with the outer margin of the body. This, combined with the thinner pedicle of the thoracic vertebrae, makes proper needle placement difficult. The posterolateral approach is preferred to the transpedicular approach in order to avoid the danger of destroying the inner cortex of the pedicle. But there can be a problems with the standard posterolateral approach. The rib can be broken, the pleura can be punctured. A new and safer approach is possible. Before penetrating the bone, the needle is positioned at the upper margin of the transverse process, 5 mm away from the pedicle. To achieve this positioning, the needle must puncture the skin 1~1.5 cm laterally and 3~5 mm cranially to the target point on the bone. This approach was used for 10 patients and we achieved good results with no serious complication.

• International Journal of Advanced Culture Technology
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• v.6 no.3
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• pp.27-36
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• 2018

This is qualitative research using grounded theory to examine the experiences that mothers of children with epilepsy can have. Data were collected through in-depth interviews, observation, and memo-taking with a total of 13 participants in this study-10 mothers taking care of children with epilepsy and 3 principal informants-and the data were analyzed using the method developed by Strauss and Corbin (1998). As a result of data analysis, 163 concepts, 26 subcategories and 8 categories were formed through open coding. Such categories were analyzed by the paradigm of the grounded theory, and as a result the experiences of the mothers of epileptic children were based on a causal condition of 'confrontation' and the central phenomenon of 'Wandering around the forest under a yoke'. The contextual conditions, which exerted influence on phenomena, were 'stigma cognition', 'personality traits' and 'health of children.' The action/interaction strategy selected by participants was 'Quietly pulling through: Bracing myself, Getting to know my enemy and myself, Taking care while hiding, Putting out one step at a time, Establishing a foothold. The intervening condition affecting action/interaction was 'the support system', and its result was 'watching.'

• Structural Engineering and Mechanics
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• v.64 no.2
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• pp.183-194
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• 2017

This paper presents the experimental investigation into a new type of steel-concrete hybrid outrigger system developed for the high-rise building structure. The steel truss is embedded into the reinforced concrete outrigger wall, and both the steel truss and concrete outrigger wall work compositely to enhance the overall structural performance of the tower structures under extreme loads. Meanwhile, metal dampers of low-yield steel material were also adopted as a 'fuse' device between the hybrid outrigger and the column. The damper is engineered to be 'scarified' and yielded first under moderate to severe earthquakes in order to protect the structural integrity of important structural components of the hybrid outrigger system. As such, not brittle failure is likely to happen due to the severe cracking in the concrete outrigger wall. A comprehensive experimental research program was conducted into the structural performance of this new type of hybrid outrigger system. Studies on both the key component and overall system tests were conducted, which reveal the detailed structural response under various levels of applied static and cyclic loads. It was demonstrated that both the steel bracing and concrete outrigger wall are able to work compositely with the low-yield steel damper and exhibits both good load carrying capacities and energy dispersing performance through the test program. It has the potential to be applied and enhance the overall structural performance of the high-rise structures over 300 m under extreme levels of loads.

• Steel and Composite Structures
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• v.46 no.3
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• pp.293-318
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• 2023

This study aims to examine the elastic stiffness properties of Elliptic-Braced Moment Resisting Frame (EBMRF) subjected to lateral loads. Installing the elliptic brace in the middle span of the frames in the facade of a building, as a new lateral bracing system not only it can improve the structural behavior, but it provides sufficient space to consider opening it needed. In this regard, for the first time, an accurate theoretical formulation has been developed in order that the elastic stiffness is investigated in a two-dimensional single-story single-span EBMRF. The concept of strain energy and Castigliano's theorem were employed to perform the analysis. All influential factors were considered, including axial and shearing loads in addition to the bending moment in the elliptic brace. At the end of the analysis, the elastic lateral stiffness could be calculated using an improved relation through strain energy method based on geometric properties of the employed sections as well as specifications of the utilized materials. For the ease of finite element (FE) modeling and its use in linear design, an equivalent element was developed for the elliptic brace. The proposed relation was verified by different examples using OpenSees software. It was found that there is a negligible difference between elastic stiffness values derived by the developed equations and those of numerical analysis using FE method.

• Coupled systems mechanics
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• v.1 no.4
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• pp.381-395
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• 2012

Dynamic response of Pile Supported Structures is highly depended on Soil Pile Structure Interaction. In this paper, by comparison of experimental and numerical dynamic responses of a prototype jacket offshore platform for both hinge based and pile supported boundary conditions, effect of soil-pile-structure interaction on dynamic characteristics of this platform is studied. Jacket and deck of a prototype platform is installed on a hinge-based case first and then platform is installed on eight skirt piles embedded on continuum monolayer sand. Dynamic characteristics of platform in term of natural frequencies, mode shapes and modal damping are compared for both cases. Effects of adding and removing vertical bracing members in top bay of jacket on dynamic characteristics of platform for both boundary conditions are also studied. Numerical simulation of responses for the studied platform is also performed for both mentioned cases using capability of ABAQUS and SACS software. The 3D model using ABAQUS software is created using solid elements for soil and beam elements for jacket, deck and pile members. Mohr-Coulomb failure criterion and pile-soil interface element are used for considering nonlinear pile soil structure interaction. Simplified modeling of soil-pile-structure interaction effect is also studied using SACS software. It is observed that dynamic characteristics of the system changes significantly due to soil-pile-structure interaction. Meanwhile, both of complex and simplified (ABAQUS and SACS, respectively) models can predict this effect accurately for such platforms subjected to dynamic loading in small range of deformation.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.261-265
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• 2006

A vertebral compression fracture can cause chronic back pain, and may also result in progressive kyphosis. The traditional treatments of a vertebral compression fracture include bed rest, analgesics and bracing. Balloon kyphoplasty can restore the vertebral height and allow safe bone cement injection into the cavity made by the balloon, which significantly reduces the risk of cement leakage compared to vertebroplasty. An 82-year-old female patient suffered from severe low back pain. Due to the intractable pain and immobility, which could not be relieved by conventional care, as well as the empty vertebral body associated with communicated fractures of the vertebral surfaces, balloon kyphoplasty, with a thicker bone cement injection than usual with balloon kyphoplasty, was chosen. The preoperative intractable pain and immobility were dramatically relieved soon after the procedure, without any complications.

• Journal of Korean Society of Steel Construction
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• v.24 no.6
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• pp.725-734
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• 2012

A new modular pier system using concrete filled circular steel tubes was suggested to realize modular bridge substructures for accelerated bridge construction. Structural details and connection details were proposed by connection multiple concrete filled tubes (CFT) for standardized products of fabrication, delivery and erection. Static tests were performed for the modular pier with suggested details under lateral load conditions for weak and strong axes. Due to the eccentricity by the bracing system, the modular pier showed 5.23 times higher flexural stiffness and 6 times greater flexural strength from the test. It is proper for the rational design to evaluate stress and deformation by frame modeling of the modular CFT pier. Structural capacity of the pier can be obtained by adjusting the spacing of the CFT columns. Design recommendations were derived from the test.

• Journal of Korean Neurosurgical Society
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• v.42 no.4
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• pp.265-270
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• 2007

Objective : The current literature implies that the use of short-segment pedicle screw fixation for spinal fractures is dangerous and inappropriate because of its high failure rate, but favorable results have been reported. The purpose of this study is to report the short term results of thoracolumbar burst and compression fractures treated with short-segment pedicle instrumentation. Methods : A retrospective review of all surgically managed thoracolumbar fractures during six years were performed. The 19 surgically managed patients were instrumented by the short-segment technique. Patients' charts, operation notes, preoperative and postoperative radiographs (sagittal index, sagittal plane kyphosis, anterior body compression, vertebral kyphosis, regional kyphosis), computed tomography scans, neurological findings (Frankel functional classification), and follow-up records up to 12-month follow-up were reviewed. Results : No patients showed an increase in neurological deficit. A statistically significant difference existed between the patients preoperative, postoperative and follow-up sagittal index, sagittal plane kyphosis, anterior body compression, vertebral kyphosis and regional kyphosis. One screw pullout resulted in kyphotic angulation, one screw was misplaced and one patient suffered angulation of the proximal segment on follow-up, but these findings were not related to the radiographic findings. Significant bending of screws or hardware breakage were not encountered. Conclusion : Although long term follow-up evaluation needs to verified, the short term follow-up results suggest a favorable outcome for short-segment instrumentation. When applied to patients with isolated spinal fractures who were cooperative with 3-4 months of spinal bracing, short-segment pedicle screw fixation using the posterior approach seems to provide satisfactory result.

• Journal of Chest Surgery
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• v.49 no.2
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• pp.92-98
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• 2016

Background: We used an Abramson technique for minimally invasive repair of pectus carinatum in patients who preferred surgery to brace therapy, had been unsuccessfully treated via brace therapy, or were unsuitable for brace therapy because of a rigid chest wall. Methods: Between July 2011 and May 2015, 16 patients with pectus carinatum underwent minimally invasive surgery. Results: The mean age of the patients was $24.35{\pm}13.20years$ (range, 14-57 years), and all patients were male. The percentage of excellent aesthetic results, as rated by the patients, was 37.5%, and the percentage of good results was 56.25%. The preoperative and postoperative Haller Index values were $2.01{\pm}0.19$ (range, 1.60-2.31), and $2.22{\pm}0.19$ (range, 1.87-2.50), respectively (p-value=0.01), and the median hospital stay was $7.09{\pm}2.91days$ (range, 5-15 days). Only one patient experienced postoperative complications. Conclusion: Minimally invasive repair is effective for the treatment of pectus carinatum, even in adult patients.

• Steel and Composite Structures
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• v.16 no.5
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• pp.491-506
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• 2014

Buckling-restrained braces (BRBs) have excellent hysteretic behavior while buckling-restrained braced frames (BRBFs) are susceptible to residual lateral deformations. To address this drawback, a novel self-centering (SC) BRB with Basalt fiber reinforced polymer (BFRP) composite tendons is presented in this work. The configuration and mechanics of proposed BFRP-SC-BRBs are first discussed. Then an 1840-mm-long BFRP-SC-BRB specimen is fabricated and tested to verify its hysteric and self-centering performance. The tested specimen has an expected flag-shaped hysteresis character, showing a distinct self-centering tendency. During the test, the residual deformation of the specimen is only about 0.6 mm. The gap between anchorage plates and welding ends of bracing tubes performs as expected with the maximum opening value 6 mm when brace is in compression. The OpenSEES software is employed to conduct numerical analysis. Experiment results are used to validate the modeling methodology. Then the proposed numerical model is used to evaluate the influence of initial prestress, tendon diameter and core plate thickness on the performance of BFRP-SC-BRBs. Results show that both the increase of initial prestress and tendon diameters can obviously improve the self-centering effect of BFRP-SC-BRBs. With the increase of core plate thickness, the energy dissipation is improved while the residual deformation is generated when the core plate strength exceeds initial prestress force.