Curvature Of Plate Research Articles

A reassessment of outer-rise seismicity and its implications for the mechanics of oceanic lithosphere

We use body-waveform modelling to constrain the source parameters of earthquakes occurring globally in oceanic lithosphere beneath the subduction zone outer rise and outer trench slope. These data are then used to map the stress state in the lithosphere of the downgoing plate as it bends into the subduction zone. Our results provide new constraints on the faulting of oceanic lithosphere at the outer rise, which is important for understanding the transmission of plate-driving forces through the subduction system. In all cases, shallow normal-faulting earthquakes are observed at the top of the plate, and are separated in depth from any deeper thrust-faulting earthquakes. No temporal variation associated with large thrust-faulting earthquakes on the subduction interface is seen in the depth extent of each type of faulting at the outer rise. The transition depth from trench-normal extension to compression is found to vary in agreement with models in which deformation is driven by the combination of in-plane stresses and bending stresses, resulting principally from slab pull. Combining the seismologically derived constraints on the thickness of the elastic core of the plate with estimates of the plate curvature, we place upper bounds on the strength of the lithosphere at the outer rise, which is required to be ≲300 MPa for a constant yield stress model, or governed by an effective coefficient of friction of ≲0.3.

Design of MFL Inspection Device for Underground Oil Tanks Based on Independent Calibration Method

The underground oil tanks are usually ellipsoid shaped and horizontal placed, in order to inspect the underground oil tanks using MFL method, a magnetization structure contains three sub parts was designed for curvature plates, the impact by the uneven placement sensors was analyzed, a new channel independent calibration method was raised. The calibration method, as well as the digital signal processing method was programmed in the inspection software, then a motor drive walking device was designed, at last the inspection device was established. Through comparison of channel independent and identical calibration methods, the experiment result using channel independent calibration method has better precision of about 1/3 discovery rate.

Analysis of NUAK1 and NUAK2 expression during early chick development reveals specific patterns in the developing head

Several human diseases are associated with the NUAK1 and NUAK2 genes. These genes encode kinases, members of the AMPK-related kinases (ARK) gene family. Both NUAK1 and NUAK2 are known targets of the serine threonine kinase LKB1, a tumor suppressor involved in regulating cell polarity. While much is known about their functions in disease, their expression pattern in normal development has not been extensively studied. Here, we present the expression patterns for NUAK1 and NUAK2 in the chick during early-stage embryogenesis, until day 3 (Hamburger and Hamilton stage HH20). Several embryonic structures, in particular the nascent head, showed distinct expression levels. NUAK1 expression was first detected at stage HH6 in the rostral neural folds. It was then expressed (HH7-11) throughout the encephalalon, predominantly in the telencephalon and mesencephalon. NUAK1 expression was also detected in the splanchnic endoderm area at HH8-10, and in the vitellin vein derived from this area, but not in the heart. NUAK2 expression was first detected at stage HH6 in the neural folds. It was then found throughout the encephalon at stage HH20. Particular attention was paid in this study to the dorsal ectoderm at stages HH7 and HH8, where a local deficit or accumulation of NUAK2 mRNA were found to correlate with the direction of curvature of the neural plate. This is the first description of NUAK1 and NUAK2 expression patterns in the chick during early development; it reveals non-identical expression profiles for both genes in neural development.

Effect of loading pulse duration on dynamic buckling of stiffened panels

Design of stiffened panels requires evaluating their stability under various loading combinations for all possible scenarios regarding material degradation or initial geometric imperfections that could affect them. Both static and dynamic loading conditions are to be investigated for assessing the buckling strength. In this work, dynamic buckling under in-plane uniform axial compression loading having the form of a transient pulse with finite duration is evaluated through nonlinear finite element modelling. A welding induced defect that consists of an initial geometric imperfection modifying the skin plate curvature in the longitudinal direction was incorporated. The Budiansky buckling criterion was employed to predict instability under this dynamic loading. The obtained results have shown that the pulse period yields a drastic effect on the buckling strength. For the considered boundary conditions, half-sine like pulses having periods that are comparable to two times the period of the first mode of natural vibrations of the stiffened plate were found to reduce hugely the buckling strength, with the dynamic buckling load representing almost only half its static value.

Performance Testing and Dimensional Analysis of Multi-Blade Wind Turbine for Low Wind Speed Applications

This article is to present the study results of small multi blade wind turbine for use in low wind speed area. In this experiment, the wind turbine has a diameter is 1 m, 30 blades. Each blade has the chord length of 6.5 cm, the length of 0.25 m, which has a curvature plate ratio of 0.15, and blade setting angle of 30 degree. Wind turbine was tested by wind tunnel at wind velocity of 3, 4 and 5 m/s. The results from the test run of, this the wind turbine give maximum mechanical power in each wind velocity of 3.66, 9.91 and 21.76 watts, respectively. From the dimensional analysis of wind rotor turbine by using Buckingham Pi theorem, the wind turbine is up to two times as large that is 2 m diameter; give maximum mechanical power increased to 14.64, 39.24 and 87.04 watts, this power can be generate electric power or use for water pumping for a household.

Damage detection in plates structures based on frequency shift surface curvature

This paper presents a novel damage detection method for plate structures based on the curvature of frequency shift surface (FSS). Unlike other commonly used vibration properties like mode shapes which have low accuracy in practice; this method uses the FSS curvature to improve the accuracy because the measurement of frequency gives better accuracy. Furthermore, it is found that the local damage will only cause local change on the FSS curvature which can be considered as abnormality because the FSS curvature of an intact plate is smooth according to the assumption that intact plate structures are often homogenous and smooth. To avoid the usage of prior knowledge of the health structure, the curve fitting technique based on local regression is adopted to simulate the FSS curvature for the intact state so that only the data from the damaged plate structure is required. Compared with traditional methods, this method is more sensitive and accurate.

A Study on Water Pumping by Using a Small Multi-Blades Windmill for Used in a Remote Area

The objective of this research is to study the small multi-blades windmill for water pumping by using a studying performance of windmill which has a curvature plate ratio of 0.07 and determine overall efficiency and evaluate economic of the system. The results from the test run of windmill rotor model in the wind tunnel at a wind velocity of 3 m/s, the windmill give maximum power coefficient of 0.296 at a tip speed ratio of 1.18. The results from the test run of the windmill-pump system at 2 m head have an overall efficiency of 0.239 at the wind velocity of 1.2 m/s. The output of 2.38 L/min, which implies a rate of return for water pumping at 0.038 USD per cubicmetre of water base on 10 year-life time of windmill.

Effect of Plate Curvature on Blast Response of Carbon/Epoxy Composite

Experimental and numerical studies wereconducted to understand the effect of plate curvature on the blast response ofcarbon/epoxy composite panels. A shock-tube system was utilized to impartcontrolled shock loading to quasi-isotropic composite panels with varying radiiof curvature. A 3D digital image correlation (DIC) technique coupled withhigh-speed photography was used to assess the out-of-plane deflection ofcomposite panels. A finite element (FE) model integrating fluid-structureinteraction to represent coupling between the air surrounding composite panels,shock wave and panels, was developed using a general-purpose FE softwareABAQUS/Explicit. The numerical results were compared to the experimental dataand showed a good correlation.

Blast response of curved carbon/epoxy composite panels: Experimental study and finite-element analysis

Experimental and numerical studies were conducted to understand the effect of plate curvature on blast response of carbon/epoxy composite panels. A shock-tube system was utilized to impart controlled shock loading to quasi-isotropic composite panels with differing range of radii of curvatures. A 3D Digital Image Correlation (DIC) technique coupled with high-speed photography was used to obtain out-of-plane deflection and velocity, as well as in-plane strain on the back face of the panels. Macroscopic post-mortem analysis was performed to compare yielding and deformation in these panels. A dynamic computational simulation that integrates fluid-structure interaction was conducted to evaluate the panel response in general purpose finite-element software ABAQUS/Explicit. The obtained numerical results were compared to the experimental data and showed a good correlation.

Global collapse and J integral analysis for inner-diameter defected curved plates in tension

Reference stress equations are widely used to predict both the limit load and the J integral response of defected structures. Their validity is key to performing a safe assessment of structural integrity (plastic collapse and fracture). An analytical reference stress equation based upon global collapse has recently been developed for curved plates with a part-through defect located at the inner diameter surface. This equation predicts decreasing reference stress values as plate curvature increases. To qualify the predictions, the authors have performed a series of finite element analyses covering a wide range of possible geometries. This paper compares the numerically obtained limit loads and J integral responses with the analytical predictions of the reference stress equation. The finite element results generally confirm the decrease of reference stress with increasing plate curvature. Highly pronounced differences may occur between flat plates and slightly curved plates. Overall, the analytically predicted decrease in reference stress is overestimated for small defects but is representative for larger defects.

10303 可視化型を利用した射出成形における板形状部のひけ生成の解明(GS-01【成形・加工(1)】)

Moldings have some fault called sink due to these shrinkage. According to previous reports, if the injection pressure and the mold clamping pressure increase, more plastics are injected in mold die. We shall be able to inhibit sink at some points where they grow. In this study, molding is preliminarily given form, such as a flat and a curvature plate. We investigate difference of deformation between flat and curvature areas. We consider how to inhibit sink by results of analysis. Therefore we compere the deformation which is measured with results of simulation and experiments of injection molding.

Increasing the mechanical strength of hybrid photodetectors based on mercury-cadmium-telluride heteroepitaxial layers

Results of the research aimed at improving the strength of hybrid photodetectors (PD) based on mercury-cadmium-telluride heteroepitaxial layers are presented. It is shown that annealing of silicon multiplexers at 157 °C in a hydrogen flow in vacuum changes the shape of indium bumps to hemispherical and levels off their mechanical properties over the plate. Controlled recovery of the natural curvature of silicon multiplexer plates and photosensitive element arrays in hybrid photodetectors at 120 °C extends their operation time. A sequence of technological operations on PD hybridization providing an increase in the efforts needed for separating photosensitive elements from silicon multiplexers at least by 75% compared to the PD with fused indium bumps is proposed.

Solar Photo-Fenton Degradation of Electro-Optical Industry Wastewater by a Pilot-Scale Fresnel Lens Assisted IPCC Reactor

In this study, a pilot-scale Fresnel lens mounted inclined plate curvature channel (IPCC) solar photo-Fenton reactor was well designed, established, and evaluated for the treatment of the electro-optical industry wastewater. Under an initial pH of 3.0, a [H2O2]0/COD0 ratio of 2, and a [H2O2]0/[Fe2

Effect of plate curvature on blast response of carbon composite panels

Experiments were conducted to study the effect of plate curvature on the blast response of 32 layered carbon composite panels. A shock tube apparatus was utilized to impart controlled blast loading on carbon fiber panels having three different radii of curvatures; infinite (Panel A), 305mm (Panel B), and 112mm (Panel C). These panels with dimensions of 203mm×203mm×2mm were held under clamped boundary conditions during the blast loading. A 3D Digital Image Correlation (DIC) technique coupled with high speed photography was used to obtain out-of-plane deflection and velocity, as well as in-plane strains on the back face of the panels. There were two types of dominant failure mechanisms observed in all the three panels: fiber breakage and inter-layer delamination. Energy loss analysis was also performed which showed that Panel C had the best energy dissipation property. Macroscopic postmortem analysis and DIC results showed that Panel C can mitigate higher intensity blast waves without initiation of catastrophic damage in the panel. Panel B could sustain the least blast intensity and exhibited catastrophic failure. Panel A exhibited intermediate blast mitigation capacity.

Conjugate analysis and effective thermal conductivities of effusion-cooled multi-layer blade sections

In order to predict the effective thermal conductivity along the chord of a typical turbine blade slice, different flat and curved – convex and concave – sections have been defined. Apart from the flat design, two different curvatures for both, the convex and concave plate, are identified. For these designs 3-D conjugate heat transfer and fluid flow analyses are performed for two blowing ratios. These analyses focus on the influence of the surface curvature on the vortex structures on the plate surface and on the cooling effectiveness on the TBC-surface as well as within the substrate layer. A multi-scale approach based on the homogenization technique is then linked to the conjugate analysis in order to predict the effective thermal conductivity of the blade sections. This method allows to calculate effective equivalent properties either for each layer or for the multilayer. The influence of the plate curvature and the blowing ratio on the effective orthotropic thermal conductivities is outlined.

FEA technique of hot plate forming process using cell-typed die with cooling device

Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG tank. Cell-typed upper and lower dies made of a framework of steel plates fitted to make a grid pattern are used in this process, and an air-cooling device is separately installed inside the lower die. A finite element analysis (FEA) technique was developed, which included hot forming, air flow, cooling and thermal deformation analysis for the hot plate forming process using the cell-typed die. Further, the convective and interface heat transfer coefficients were used to reproduce analytically the effects of the cooling device in the hot plate forming analysis. A small-scale model test of the process was conducted to verify the FEA technique. The analysis results show that the curvature of the final plate agrees well with that of the designed experiment within a maximum relative error of 0.03% at the corner of the plate.

Parametric study of a SPH high velocity impact analysis – A birdstrike windshield application

During its life cycle an aircraft flies on the risk of impacting foreign objects. According to the aeronautical specifications, the term “birdstrike” indicates the collision between a bird and an aircraft front facing component, which includes windshield, nacelles, compressor blade, wing leading edge or even flaps, when extended.This paper is part of a research focused on the study, with the help of finite element analysis, of an aircraft windshield-surround structure with an innovative configuration that satisfies the bird-strike requirement according to the European and US aviation regulations 25.631 on the “Bird-strike Damage”[1,2].Firstly the paper provides a numerical analysis of a simplified, but dimensionally realistic, square flat windshield model subjected to impact by a 1.8kg bird model at 155m/s with an impact angle of 90°. The FE-SPH coupled approach is used to simulate the birdstrike by using the explicit finite element solver code LS-Dyna.The second step involves a parametric analysis on the square model to estimate the influence of the target geometry, the impact angle, and the plate curvature on the impact response of the windshield structure. The goal of these numerical simulations is the evaluation of the windshield capability to absorb the impact energy of a birdstrike event, in a safe and efficient way which is compliant with the airworthiness rules.The aim of this work is to define a scientific and methodological approach to the study of the birdstrike problem. The collection of results and experiences achieved by the previous simplified realistic model can be applied to perform a certification test simulation and define possible guidelines for the design of a bird-proof airplane windshield.

Curvature tailoring of unsymmetric laminates with an initial curvature

An unsymmetric laminated composite having bi-stability is interesting as a morphing structure because it can sustain large deformation without energy supply and the deformed state is stable. Especially, inducing different curvature values at each stable state is important for the practical application of unsymmetric laminates. In this study, we propose a method for tailoring the curvature of unsymmetric cross-ply laminates by curing the composite on a curved tool plate. The results show that the final normal curvature tensor of unsymmetric laminates is the summation of the tool plate curvature tensor and the normal curvature tensor of the laminates.

Effect of rolling parameters on plate curvature during snake rolling

In order to predict the plate curvature during snake rolling, FE model was constructed based on plane strain assumption. The accuracy of the FE model was verified by the comparison between the plate curvature conducted by FE model and experiment respectively. By using FE model, the effect of offset distance, speed ratio, reduction, roll radius and initial plate thickness on the plate curvature during snake rolling was investigated. The experimental results show that, a proper offsetting distance can efficiently decrease plate curvature, however an excessive offsetting distance will increase plate curvature. A larger speed ratio, reduction will cause a large plate curvature, however a larger roll radius has effect to reduce plate curvature. Plate which undergoes a larger reduction and plate with a larger initial thickness always need a larger offset distance to keep the plate the minimum plate curvature, but for a larger roll radius a smaller offset distance is needed.

Effect of plate curvature on blast response of aluminum panels

Experimental and numerical studies were conducted to understand the effect of plate curvature on blast response of aluminum panels. A shock tube apparatus was utilized to impart controlled shock loading to aluminum 2024-T3 panels having three different radii of curvatures: infinity (panel A), 304.8 mm (panel B), and 111.8 mm (panel C). Panels with dimensions of 203.2 mm × 203.2 mm × 2 mm were held with mixed boundary conditions before applying the shock loading. A 3D Digital Image Correlation (DIC) technique coupled with high speed photography was used to obtain out-of-plane deflection and velocity, as well as in-plane strain on the back face of the panels. Macroscopic postmortem analysis was performed to compare the yielding and plastic deformation in the three panels. The results showed that panel C had the least plastic deformation and yielding as compared to the other panels. A dynamic computational simulation that incorporates the fluid-structure interaction was also conducted to evaluate the panel response. The computational study utilized the Dynamic System Mechanics Analysis Simulation (DYSMAS) software. The model consisted of the shock tube wall, the aluminum plate, and the air (both internal and external) to the tube walls. The numerical results were compared to the experimental data. The comparison between the experimental results and the numerical simulation showed a high level of correlation using the Russell error measure.