scholarly journals Examination of a Low-Profile Spinal Implant

2017 ◽  
Vol 11 (6) ◽  
pp. 895-901
Author(s):  
Takuto Iwade ◽  
Noriyuki Hisamori ◽  
Junichi Fujita ◽  
Kenji Yamaya ◽  
◽  
...  
Keyword(s):  
Contact Area ◽  
Cyclic Load ◽  
Load Test ◽  
Screw Thread ◽  
Static Load Test ◽  
Spinal Implant ◽  
Thread Surface ◽  
Low Profile ◽  
Screw Threads

Most spine implant devices are fabricated outside Japan, and therefore do not always fit the bodies of Japanese people. This causes a quality-of-life (QOL) problem in which patients feel the embedded implant devices on their back. The aim of this study was to develop more compact and lower-profile spine implant devices. Three types of devices with different heights and different screw threads were created, and the removal torque (fitting force) of the devices was measured after a static load test and cyclic load test. In addition, the screw thread surface was observed in detail after the tests. The results indicated that the mechanism of the reduction in the fitting force was related to partial contact due to abrasion or plastic deformation of the screw thread surface and decrease in the contact area between the screw threads caused by the increased diameter of the upper opening of the implant device after tightening. Therefore, we concluded that lowering the height of the implant device, securing the number of the screw threads, and securing the contact area of the threads are important in developing a low-profile spine implant.

Optical Simulation of Omnidirectional Inspection System for Screw Threads

2014 ◽  
Vol 625 ◽  
pp. 706-711
Author(s):  
Keun Park ◽  
Chang Hun Lee ◽  
Seung Woo Ra
Keyword(s):  
Surface Defects ◽  
Optical Measurement ◽  
Optical Simulation ◽  
Inspection System ◽  
Light Illumination ◽  
Screw Thread ◽  
Simulation Based ◽  
Screw Threads ◽  
Optical Paths

Machine vision systems have been used in the automatic inspection of screw threads using backlight illumination for the inspection of the screw thread profiles. In this study, an alternative inspection system based on front light illumination is developed to directly obtain thread images so that surface defects can be measured. To realize such an inspection system, an omnidirectional optical measurement device is proposed to obtain 360oimages of screws for inspection of whole thread regions. Optical simulation based on ray tracing is then performed to analyze optical paths and to optimize the image quality of the designed optical system.

Prediction of Vertical Ultimate Bearing Capacity in Piles Based on the Improved Hyperbolic Model

2011 ◽  
Vol 250-253 ◽  
pp. 2271-2275
Author(s):  
Cheng Wang ◽  
Qi Zhang
Keyword(s):  
Bearing Capacity ◽  
Ultimate Bearing Capacity ◽  
Load Test ◽  
Hyperbolic Model ◽  
Maximum Point ◽  
Static Load Test ◽  
Hyperbolic Curve ◽  
The Mathematical Model ◽  
Test Pile

Vertical static load test is widely used in the determination of pile bearing capacity, the mathematical model used to fit test pile data in determining the bearing capacity is essential. From the perspective of analytic geometry, the paper analyzes the traditional method of hyperbola, of which the asymptotic line of equilateral hyperbola was used to determine the ultimate bearing capacity. By extending the equal-axed conditions, a more general form of hyperbolic equation is derived and feasibility of such method is also analyzed, which indicates that the maximum point of curvature in such hyperbolic curve can determine the ultimate bearing capacity and such method is proved to be reasonable in practical projects.

scholarly journals Experimental Study on Mechanical Property of Stiffening-ribbed-hollowpipe Reinforced Concrete Girderless Floor with Four Clamped Edges Supported

2013 ◽  
Vol 7 (1) ◽  
pp. 170-178 ◽  
Author(s):  
Weijun Yang ◽  
Yongda Yang ◽  
Jihua Yin ◽  
Yushuang Ni
Keyword(s):  
Mechanical Property ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Reinforced Concrete ◽  
Large Scale ◽  
Load Test ◽  
Static Load Test ◽  
Loading Test ◽  
Element Analysis ◽  
Clamped Edges

In order to study the basic mechanical property of cast-in-place stiffening-ribbed-hollow-pipe reinforced concrete girderless floor, and similarities and differences of the structural performance compared with traditional floor, we carried out the destructive stage loading test on the short-term load test of floor model with four clamped edges supported in large scale, and conducted the long-term static load test. Also, the thesis conducted finite element analysis in virtue of ANSYS software for solid slab floor, stiffening-ribbed-hollow-pipe floor and tubular floor. The experiment indicates that the developing process of cracks, distribution and failure mode in stiffening-ribbed-hollow-pipe floor are similar to that of solid girderless floor, and that this kind of floor has higher bearing capacity and better plastic deformation capacity. The finite element analysis manifests that, compared with solid slab floor, the deadweight of stiffening-ribbed-hollow-pipe floor decreases on greater level while deformation increases little, and that compared with tubular floor, this floor has higher rigidity. So stiffening-ribbed-hollow-pipe reinforced concrete girderless floor is particularly suitable for long-span and large-bay building structure.

scholarly journals HWN* Mobility Management Considering QoS, Optimisation and Cross Layer Issues

2007 ◽  
Vol 3 (4) ◽  
pp. 225 ◽  
Author(s):  
Chong Shen
Keyword(s):  
Mobility Management ◽  
Ad Hoc ◽  
Routing Algorithm ◽  
Cross Layer ◽  
Cross Layer Design ◽  
Relay Nodes ◽  
High Profile ◽  
Low Profile ◽  
Avoidance Control

In this paper, we address mobility management for 4th generation heterogeneous networks from a quality of service (QoS), optimisation and cross layer design perspective. Users are classified as high profile, normal profile and low profile according to their differentiated service requirements. Congestion avoidance control and adaptive handover mechanisms are implemented for efficient cooperation within the mobile heterogeneous network environment consisting of a TDMA network, ad hoc network and relay nodes. A previous proposed routing algorithm is also revised to include mobility management.

scholarly journals MODELING OF THE JACKED PILE STATIC LOAD TEST WITH PLAXIS 3D / SPAUSTINIO POLIO BANDYMO STATINE APKROVA MODELIAVIMAS PLAXIS 3D

2016 ◽  
Vol 8 (5) ◽  
pp. 495-498
Author(s):  
Tautvydas Statkus
Keyword(s):  
Building Materials ◽  
Model Building ◽  
Static Load ◽  
Load Test ◽  
Static Load Test ◽  
Model Geometry ◽  
Comparison Of The Results ◽  
3D Software ◽  
Installation Technology ◽  
Plaxis 3D

In this article jacked pile installation technology and its current processes, altering the base physical and mechanical characteristics are discussed. For the jacked pile static load test simulation Plax 3D software was selected, the opportunities and developments were described. Model building, materials, models, model geometry, finite elements, boundary conditions and assumptions adopted in addressing problems described in detail. Three different tasks formulated and load-settlement dependence a comparison of the results with the experiment given. Conclusions are formulated according to the modeling results. Šiame straipsnyje aptarta spaustinių polių įrengimo technologija ir ją taikant vykstantys procesai, keičiantys pagrindo fizines ir mechanines charakteristikas. Spaustinio polio bandymui statine apkrova modeliuoti pasirinktas PLAXIS 3D programinis paketas ir aprašytos jo galimybės bei raida. Detaliai nupasakotas modelio kūrimas, medžiagų modeliai, modelio geometrija, baigtiniai elementai, kraštinės sąlygos ir priimamos prielaidos sprendžiant problemą. Suformuluoti trys sprendžiami uždaviniai ir apkrovos bei nuosėdžio priklausomybe pateikiamas rezultatų palyginimas su eksperimentu. Atsižvelgiant į modeliavimo rezultatus suformuluotos išvados.

Static Load Test of Frame-Structure Slab

2013 ◽  
Vol 790 ◽  
pp. 227-230
Author(s):  
Jian Feng Su ◽  
Yu Feng Xu
Keyword(s):  
Carrying Capacity ◽  
Static Load ◽  
Load Test ◽  
Frame Structure ◽  
Test Results ◽  
Static Load Test ◽  
Important Method ◽  
Floor Slab ◽  
Testing Scheme

Floor slab static load test is a important method to judge the performance and carrying capacity of the slab. This paper, with the background of a factory frame-structure slab, introduced the testing scheme, the details of the testing process as well as the test results. The testing cases provide a useful reference for the same type of project.

scholarly journals Comparison of Numerical Analyses with a Static Load Test of a Continuous Flight Auger Pile

2014 ◽  
Vol 22 (4) ◽  
pp. 1-10 ◽  
Author(s):  
Michal Hoľko ◽  
Jakub Stacho
Keyword(s):  
Load Distribution ◽  
Static Load ◽  
Numerical Models ◽  
Load Test ◽  
Numerical Analyses ◽  
Static Load Test ◽  
Material Models ◽  
The Common ◽  
Constitutive Material ◽  
The Impact

Abstract The article deals with numerical analyses of a Continuous Flight Auger (CFA) pile. The analyses include a comparison of calculated and measured load-settlement curves as well as a comparison of the load distribution over a pile's length. The numerical analyses were executed using two types of software, i.e., Ansys and Plaxis, which are based on FEM calculations. Both types of software are different from each other in the way they create numerical models, model the interface between the pile and soil, and use constitutive material models. The analyses have been prepared in the form of a parametric study, where the method of modelling the interface and the material models of the soil are compared and analysed. Our analyses show that both types of software permit the modelling of pile foundations. The Plaxis software uses advanced material models as well as the modelling of the impact of groundwater or overconsolidation. The load-settlement curve calculated using Plaxis is equal to the results of a static load test with a more than 95 % degree of accuracy. In comparison, the load-settlement curve calculated using Ansys allows for the obtaining of only an approximate estimate, but the software allows for the common modelling of large structure systems together with a foundation system.

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