• Structural Engineering and Mechanics
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• v.47 no.1
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• pp.59-73
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• 2013

The Xiaolan channel super large bridge is unique in style and with greatest span in the world with a total length of 7686.57 m. The main bridge with spans arranged as 100m+220m+100m is a combined structure composed of prestressed concrete V-shape rigid frame and concrete-filled steel tubular flexible arch. First of all, the author compiles APDL command flow program by using the unit birth-death technique and establishes simulation calculation model in the whole construction process. The creep characteristics of concrete are also taken into account. The force ratio of the suspender, arch and beam is discussed. The authors conduct studies on the three-plate webs's rule of shear stress distribution, the box girder's longitudinal bending normal stress on every construction stage, meanwhile the distribution law of longitudinal bending normal stress and transverse bending normal stress of completed bridge's box girder. Results show that, as a new combined bridge, it is featured by: Girder and arch resist forces together; Moment effects of the structure are mainly presented as compressed arch and tensioned girder; The bridge type brings the girder and arch on resisting forces into full play; Great in vertical stiffness and slender in appearance.

• Archives of Plastic Surgery
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• v.36 no.3
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• pp.318-321
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• 2009

Purpose: The bony mallet finger injury is generally managed by conservative treatments, but operative treatments are needed especially when the fractures involve above 30% of articular surface or distal phalanx is accompanied by subluxation in the volar side. This is the reason they often result in chronic instability, articular subluxation and unsatisfactory cosmetic. In this report, We describe new method using the hook plate as an operative treatment of Mallet finger deformity. Methods: Among 13 patients with Mallet finger deformity who came from February 2006 to February 2008, six patient were included in surgical indication. Under local anesthesia, H or Y type incision was made at the DIP joint area. After the DIP joint extension, the hook plate was put on the fracture line, and one self tapping screw was used for fixation. 2 hole plate which was one of the holes in 1.5 mm diameter was cut in almost half and bended through approximately $100^{\circ}$. Results: In all six cases which applied the hook plate, complications such as loss of reduction or nail deformity were not seen. In only one patient, hook pate was removed due to inflammatory reaction after surgery. At 2 weeks after operation, active motion of DIP joint was performed. The result was satisfactory not only cosmetically but also functionally. At 6 weeks after operation, the range of motion of DIP joint was average $64^{\circ}$. Conclusion: The purpose of the operative treatment for mallet finger deformity using the hook plate is to provide anatomical reduction with rigid fixation and to prevent contracture at the DIP joint. While other operations take 6 weeks, the operation using the hook plate begins an active motion at 2 weeks after operation. Complication rate was low and the method is rather simple. Thus, the operation using the hook plate is recommended as a good alternative method of the mallet finger deformity treatment.

• Journal of the Korean Society for Railway
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• v.15 no.6
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• pp.588-596
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• 2012

This paper presents a new semi-analytical annular Mindlin plate element with which out-of-plane natural vibration of thick disks can be analyzed simply, efficiently, and accurately through FEM by including effects of rotary inertia and transverse shear deformation. Using static deformation modes which are exact solutions of equilibrium equations of annular Mindlin plate, the element interpolation functions, stiffness and mass matrices corresponding to each number of nodal diameters are derived. The element is capable of representing out-of-plane rigid-body motions exactly and free from shear locking. Natural frequencies of uniform and multi-step disks with or without concentric ring support are analyzed by applying the presented element. Such results are compared with theoretical predictions of previous works or FEA results obtained by using two-dimensional shell element to investigate the convergence and accuracy of the presented element.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.619-625
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• 2010

Purpose: Trapdoor orbital blowout fracture is most common in orbital blowout fracture. Various materials have been used to reconstruct orbital floor blowout fracture. Absorbable alloplastic implants are needed because of disadvantages of nonabsorbable alloplastic materials and donor morbidity of autogenous tissue. The aim of the study is to evaluate usefulness of absorbable mesh plate as a reconstructive material for orbital blowout fractures. Methods: From December 2008 to October 2009, 18 trapdoor orbital floor blowout fracture patients were treated using elevator fixation, depressor fixation, or elevatordepressor fixation techniques with absorbable mesh plates and screw, depending on degree of orbital floor reduction, because absorbable mesh plates are less rigid than titanium plates and other artificial substitutes. Results: Among 18 patients, 5 elevator fixation, 4 depressor fixation, and 9 elevator and depressor fixation technique were performed. In all patients, postoperative computed tomographic (CT) scan showed complete reduction of orbital contents and orbital floor, and no displacement of bony fragment and mesh plate. Mean follow-up was 10 months. There were no significant intraoperative or postoperative complications. Conclusion: Three different techniques depending on the degree of orbital floor reduction are useful for open reduction and internal fixation of trapdoor orbital floor blowout fracture with absorbable mesh plates.

• Journal of Korean Society of Steel Construction
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• v.13 no.5
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• pp.503-511
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• 2001

Structures are designed against earthquakes and reinforced concrete shear walls or steel bracings are usually used as aseismic resistant element. However their hysteretic characteristics in plastic region ductility and capacity of energy absorption are not always good. Besides their stiffness is so rigid that structure designed by static analysis is occasionally disadvantageous. when dynamically analized. Generally a steel plate subjected to shear force has a good deformation capacity Also it has been considered to retain comparative shear strength and stiffness Steel shear wall can be used as lateral load resistant element for seismic design. However there was little knowledge concerning shear force-deformation characteristics of steel plates up to their collapse state In this study a series of shear loading tests of steel plate collapse state. In this study a series of shear loading tests of steel plate surrounded by vertical and horizontal ribs were conducted with the parameters of D/H ratios rib type and the loading patterns. The test result is discussed and analyzed to obtain several restoring characteristics. that is shear force-deformation stiffness and yield strength etc.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.1
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• pp.32-38
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• 2005

The efficacy of bioresorbable fixation has recently been described in the osseosynthesis of the oral & maxillofacial region. However, a liitle data exist regarding the use of biodegradable plates and screws for the internal fixation of human mandible fractures. The purpose of this study is to analyze and compare the treatment of mandibular fractures by using a bioresorbable fixation system with conventional titanium system in human mandible fractures. eighteen patients constituted the bioresorbable fixation group and twenty-five patients constituted the titanium fixation group. Both groups underwent open reduction and internal fixation by use of a bioresorbable system or a titanium fixation system. Panoramic radiograph were obtained preoperatively, immediately postoperatively after reduction, at 6 months and at 12 months postoperatively. In the bioresorbable fixation group, complication(infection) occurred in 1 patient(5.6%) and was resolved by incision & drainage, plate removal and antibiotics without untoward sequelae. 2 patients(8.0%) experienced complications in the titanium fixation group and were treated using conservative treatment. There was no statistical difference in complication rates between two groups. Our data supported the use of bioresorbale plate fixation in mandibular fractures as a means of avoiding the potential and well documented problems with rigid titanium fixation systems. In conclusion, the bioresorbable fixation system provide a reliable and sufficient alternative to conventional titanium plate system.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.2
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• pp.164-170
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• 2005

The purpose of this study was to compare a sample of patients who had condylar fractures treated with open reduction using different plating techniques, to evaluate which plating technique is useful for stable fixation for fractures of the mandibular condyle and to evaluate effectiveness of resorbable miniplate. There were 60 patients (41 males, 19 females) whose condylar fractures were treated with open reduction. Rigid fixation was performed with a single miniplate, double miniplate ot one miniplate & one microplate and single resorbable plate. All patients remained intermaxillary fixation for 1 week postoperatively. Active physiotherapy was started after 2 weeks postoperatively. Radiographic evaluation (plate fracture, plate bending, screw loosening, displacement of condyle etc.) was performed at pre-operative, immediate, 2 weeks, 1 month, 3 months, 6 months after surgery. Clinical evaluation included degree of mouth opening, occlusion, mandibular lateral excursion, infection and facial nerve paralysis. In radiographic evaluation, displacement of fractured condylar segment associated with plate bending or screw loosening were showed 6 cases and 3 cases for single miniplate system and resorbable miniplate system. There was no patients who have this problem on double miniplate system. The results revealed that the application of two miniplates were more recommendable than single miniplates. When we select resorbable miniplate system, we should consider the type of fractures, post-operative treatment protocol and surgical technique.

• Advances in nano research
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• v.8 no.2
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• pp.135-148
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• 2020

The incorporation of carbon nanotubes in a polymer matrix makes it possible to obtain nanocomposite materials with exceptional properties. It's in this scientific background that this work was based. There are several theories that deal with the behavior of plates, in this research based on the Mindlin-Reissner theory that takes into account the transversal shear effect, for analysis of the critical buckling load of a reinforced polymer plate with parabolic distribution of carbon nanotubes. The equations of the model are derived and the critical loads of linear and parabolic distribution of carbon nanotubes are obtained. With different disposition of nanotubes of carbon in the polymer matrix, the effects of different parameters such as the volume fractions, the plate geometric ratios and the number of modes on the critical load buckling are analysed and discussed. The results show that the critical buckling load of parabolic distribution is larger than the linear distribution. This variation is attributed to the concentration of reinforcement (CNTs) at the top and bottom faces for the X-CNT type which make the plate more rigid against buckling.

• Advances in aircraft and spacecraft science
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• v.3 no.3
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• pp.243-257
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• 2016

The increase of air traffic volume has brought an increasing amount of issues related to carbon and NOx emissions and noise pollution. Aircraft manufacturers are concentrating their efforts to develop technologies to increase aircraft efficiency and consequently to reduce pollutant discharge and noise emission. Ultra High By-Pass Ratio engine concepts provide reduction of fuel consumption and noise emission thanks to a decrease of the jet velocity exhausting from the engine nozzles. In order to keep same thrust, mass flow and therefore section of fan/nacelle diameter should be increased to compensate velocity reduction. Such feature will lead to close-coupled architectures for engine installation under the wing. A strong jet-wing interaction resulting in a change of turbulent mixing in the aeroacoustic field as well as noise enhancement due to reflection phenomena are therefore expected. On the other hand, pressure fluctuations on the wing as well as on the fuselage represent the forcing loads, which stress panels causing vibrations. Some of these vibrations are re-emitted in the aeroacoustic field as vibration noise, some of them are transmitted in the cockpit as interior noise. In the present work, the interaction between a jet and wing or fuselage is reproduced by a flat surface tangential to an incompressible jet at different radial distances from the nozzle axis. The change in the aerodynamic field due to the presence of the rigid plate was studied by hot wire anemometric measurements, which provided a characterization of mean and fluctuating velocity fields in the jet plume. Pressure fluctuations acting on the flat plate were studied by cavity-mounted microphones which provided point-wise measurements in stream-wise and spanwise directions. Statistical description of velocity and wall pressure fields are determined in terms of Fourier-domain quantities. Scaling laws for pressure auto-spectra and coherence functions are also presented.

• Progress in Medical Physics
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• v.6 no.2
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• pp.111-125
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• 1995

The stress distribution of bone is altered by the rigid bone plate, sometimes resulting in unfavorable osteoporosis. The rigidity and the biocompatibility are important factors for the design of prosthesis, however, it is also necessary to consider the effect on the bone remodeling. In this paper, it is attempted to establish an approximate and simple method to predict the trend of the configuration of surface bone remodeling upon a bone plate using stress analysis. Thus, three dimensional finite element model of plated-human femur is generated and simulated. In addition, the stress difference method (SDM) is introduced and attempted to demonstrate the configuration of surface bone remodeling of the plated-human femur.