Institute of Scientific and Technical Information of China (English)
L. B. Chen; F. Xi; J. L. Yang
2007-01-01
A new elastic-plastic impact-contact model is proposed in this paper. By adopting the principle of minimum acceleration for elastic-plastic continue at finite deformation,and with the aid of finite difference method, the proposed model is applied in the problem of dynamic response of a clamped thin circular plate subjected to a projectile impact centrally. The impact force history and response characte-ristics of the target plate is studied in detail. The theoreti-cal predictions of the impact force and plate deflection are in good agreements with those of LDA experimental data.Linear expressions of the maximum impact force/transverse deflection versus impact velocity are given on the basis of the theoretical results.
Chaotic Motion of Corrugated Circular Plates
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Large deflection theory of thin anisotropic circular plates was used to analyze the bifurcation behavior and chaotic phenomena of a corrugated thin circular plate with combined transverse periodic excitation and an in-plane static boundary load. The nonlinear dynamic equation for the corrugated plate was derived by employing Galerkin's technique. The critical conditions for occurrence of the homoclinic and subharmonic bifurcations as well as chaos were studied theoretically using the Melnikov function method. The chaotic motion was also simulated numerically using Maple, with the Poincaré map and phase curve used to evaluate when chaotic motion appears. The results indicate some chaotic motion in the corrugated plate. The method is directly applicable to chaotic analysis of an isotropic circular plate.
Underwater Shock Response of Circular HSLA Steel Plates
Directory of Open Access Journals (Sweden)
R. Rajendran
2000-01-01
Full Text Available Studies on shock response of circular plates subjected to underwater explosion is of interest to ship designers. Non-contact underwater explosion experiments were carried out on air backed circular High Strength Low Alloy (HSLA steel plates of 4 mm thickness and 290 mm diameter. The experiments were carried out in two phases. In the first phase, strain gauges were fixed at intervals of 30 mm from the centre of the plate and strains were recorded for the shock intensity gradually increasing to yielding. Semi-analytical models were derived for the elastic strain prediction which showed good agreement with the experiments. Dynamic yield stress and the shock factor for yielding were established. In the second phase, individual plates were subjected to increasing shock severity until fracture and the apex bulge depth and the thickness strains were measured. Empirical models were derived to predict the plastic deformation which were validated through a fresh set of experiments. Analysis of the fractured surface by visual examination showed that there was slant fracture indicating ductile mode of failure and the same was corroborated by Scanning Electron Microscopic (SEM examination.
Wave Interaction with Dual Circular Porous Plates
Institute of Scientific and Technical Information of China (English)
Arpita Mondal; R.Gayen
2015-01-01
In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green’s integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cum-collocation method where the behaviour of the potential functions at the tips of the plates have been used. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement.
Wave interaction with dual circular porous plates
Mondal, Arpita; Gayen, R.
2015-12-01
In this paper we investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green's integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cum-collocation method using the behaviour of the potential functions at the tips of the plates. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement.
The comparative study for the isotropic and orthotropic circular plates
Popa, C.; Tomescu, G.
2016-08-01
The aim of study is static bending analysis of an isotropic circular plate using analytical method i.e. Classical Plate Theory, Finite Element software ANSYS and experimental methods. The diameter of circular plate, material properties, like modulus of elasticity (E), poissons ratio (µ) and intensity of loading is assumed at the initial stage of research work. In comparison with this plane plate we analyze a plate of same dimensions and charge, but having ribs, to see the advantage of the rigidify. The two plates are fixed supported subjected to uniformly distributed load.
Bending and buckling behavior analysis of foamed metal circular plate.
Fan, Jian Ling; Ma, Lian Sheng; Zhang, Lu; De Su, Hou
2016-07-04
This paper establishes a density gradient model along the thickness direction of a circular plate made of foamed material. Based on the first shear deformation plate theory, the result is deduced that the foamed metal circular plate with graded density along thickness direction yields axisymmetric bending problem under the action of uniformly distributed load, and the analytical solution is obtained by solving the governing equation directly. The analyses on two constraint conditions of edge radial clamping and simply supported show that the density gradient index and external load may affect the axisymmetric bending behavior of the plate. Then, based on the classical plate theory, the paper analyzes the behavior of axisymmetric buckling under radial pressure applied on the circular plate. Shooting method is used to obtain the critical load, and the effects of gradient nature of material properties and boundary conditions on the critical load of the plate are analyzed.
On electrostatically actuated NEMS/MEMS circular plates
Caruntu, Dumitru I.; Alvarado, Iris
2011-04-01
This paper deals with electrostatically actuated micro and nano-electromechanical (MEMS/NEMS) circular plates. The system under investigation consists of two bodies, a deformable and conductive circular plate placed above a fixed, rigid and conductive ground plate. The deformable circular plate is electrostatically actuated by applying an AC voltage between the two plates. Nonlinear parametric resonance and pull-in occur at certain frequencies and relatively large AC voltage, respectively. Such phenomena are useful for applications such as sensors, actuators, switches, micro-pumps, micro-tweezers, chemical and mass sensing, and micro-mirrors. A mathematical model of clamped circular MEMS/NEMS electrostatically actuated plates has been developed. Since the model is in the micro- and nano-scale, surface forces, van der Waals and/or Casimir, acting on the plate are included. A perturbation method, the Method of Multiple Scales (MMS), is used for investigating the case of weakly nonlinear MEMS/NEMS circular plates. Two time scales, fast and slow, are considered in this work. The amplitude-frequency and phase-frequency response of the plate in the case of primary resonance are obtained and discussed.
Modeling and Simulation of Nonlinear Micro-electromechanical Circular Plate
Directory of Open Access Journals (Sweden)
Chin-Chia Liu
2013-09-01
Full Text Available In the present study, the hybrid differential transformation and finite difference method is applied to analyze the dynamic behavior of the nonlinear micro-electromechanical circular plate actuated by combined DC / AC loading schemes. The analysis takes account of the axial residual stress and hydrostatic pressure acting on micro circular plate upper surface. The dynamic response of the plate as a function of the magnitude of the AC driving voltage is explored. Moreover, the effect of the initial gap height on the pull-in voltage of the plate is systematically explored.
Plastic collapse load of corroded steel plates
Indian Academy of Sciences (India)
Rahbar Ranji Ahmad
2012-06-01
Corrosion is one of the detrimental phenomena which reduces strength of structures. It is common practice to assume a uniform thickness reduction for general corrosion. Since the actual corroded plate has rough surfaces, to estimate the remaining strength of corroded structures, typically a much higher level of accuracy is required. The main aim of present work is to study plastic collapse load of corroded steel plates with irregular surfaces under tension. Non-linear ﬁnite element method by using computer code ANSYS was employed to determine plastic collapse load. By comparing the results with uniform thickness assumption, a reduction factor was proposed. It is found that by uniform thickness assumption, plastic collapse load of corroded plates are overestimated.
NONLINEAR VIBRATION OF CIRCULAR SANDWICH PLATES UNDER CIRCUMJACENT LOAD
Institute of Scientific and Technical Information of China (English)
DU Guo-jun; MA Jian-qing
2006-01-01
Based on yon Karman plate theory, the issue about nonlinear vibration for circular sandwich plates under circumjacent load with the loosely clamped boundary condition was researched. Nonlinear differential eigenvalue equations and boundary conditions of the problem were formulated by variational method and then their exact static solution can be got. The solution was derived by modified iteration method, so the anslytic relations between amplitude and nonlinear oscillating frequency for circular sandwich plates were obtained. When circumjacent load makes the lowest natural frequency zero,critical load is obtained.
The postbuckling analysis of laminated circular plate with elliptic delamination
Chen, Deliang; Chen, Changping; Fu, Yiming
2011-01-01
Based on the Von Karman plate theory, considering the effect of transverse shear deformation, and using the method of the dissociated three regions, the postbuckling governing equations for the axisymmetric laminated circular plates with elliptical delamination are derived. By using the orthogonal point collocation method, the governing equations, boundary conditions and continuity conditions are transformed into a group of nonlinear algebraically equation and the equations are solved with the alternative method. In the numerical examples, the effects of various elliptical in shape, delamination depth and different material properties on buckling and postbuckling of the laminated circular plates are discussed and the numerical results are compared with available data.
Capacity of a condenser whose plates are circular arcs
Karp, D.
2006-01-01
We find an asymptotic formula for the conformal capacity of a plane condenser both plate of which are concentric circular arcs as the distance between them vanishes. This result generalizes the formula for the capacity of parallel linear plate condenser found by Simonenko and Chekulaeva in 1972 and sheds light on the problem of finding an asymptotic formula for the capacity of condenser whose plates are arbitrary parallel curves. This problem was posed and partially solved by R. K\\"{u}hnau in...
Electroless metal plating of plastics
Krause, Lawrence J.
1984-01-01
Process for plating main group metals on aromatic polymers is carried out by the use of a nonaqueous solution of a salt of an alkali metal in a positive valence state and a main group metal in a negative valence state with contact between the solution and polymer providing a redox reaction causing the deposition of the main group metal and the reduction of the polymer. Products from the process exhibit useful decorative and electrical properties.
ANALYTICAL RELATIONS BETWEEN EIGENVALUES OF CIRCULAR PLATE BASED ON VARIOUS PLATE THEORIES
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Based on the mathematical similarity of the axisymmetric eigenvalue problems of a circular plate between the classical plate theory(CPT), the first-order shear deformation plate theory(FPT) and the Reddy's third-order shear deformation plate theory(RPT), analytical relations between the eigenvalues of circular plate based on various plate theories are investigated. In the present paper, the eigenvalue problem is transformed to solve an algebra equation. Analytical relationships that are expressed explicitly between various theories are presented. Therefore, from these relationships one can easily obtain the exact RPT and FPT solutions of critical buckling load and natural frequencyfor a circular plate with CPT solutions. The relationships are useful for engineering application, and can be used to check the validity, convergence and accuracy of numerical results for the eigenvalue problem of plates.
Modal radiation patterns of baffled circular plates and membranes
DEFF Research Database (Denmark)
Christiansen, Thomas Lehrmann; Hansen, Ole; Thomsen, Erik Vilain
2014-01-01
The far field velocity potential and radiation pattern of baffled circular plates and membranes are found analytically using the full set of modal velocity profiles derived from the corresponding equation of motion. The derivation is valid for a plate or membrane subjected to an external excitation...... that of a monopole, while the non-axisymmetric modes exhibit multipole behavior. Numerical results are also given, demonstrating the implications of having non-axisymmetric excitation using both a point excitation with varying eccentricity and a homogeneous excitation acting on half of the circular radiator....
Analysis and Design of Circular Plate MR Fluids Brake
Institute of Scientific and Technical Information of China (English)
Yang Yan; Lin Chang-Hua; Li Hui; Zhou Jing
2004-01-01
A magnetorheological (MR) fluids brake is a device to achieve brake by shear force of MR fluids. A MR rotary brake has the property that its braking torque changes quickly in response to an external magnetic field. In this study, the design method of the circular plate MR fluids brake is investigated theoretically. The equation of the torque transmitted by the MR fluids in the brake is derived to provide the theoretical foundation in the design of the brake. Based on this equation, after mathematically manipulated, the calculations of the volume, thickness and width of the MR fluids within the circular plate MR fluids brake are yield.
Numerical simulation of circular jet impinging on hot steel plate
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
Flow structure and heat transfer characteristics of an axisymmetric circular jet impinging on a hot 1Cr18Ni9Ti medium plate have been simulated numerically using computational fluid dynamic (CFD) code. The relation between flow field of jet impingement and its heat transfer capability is analyzed, and the phenomenon that heat transfer at stagnation point is smaller than that of points directly around is discussed. The simulation result provides boundary conditions for thermalanalysis of medium plate quenching.
Thermally Induced Principal Parametric Resonance in Circular Plates
Directory of Open Access Journals (Sweden)
Ali H. Nayfeh
2002-01-01
Full Text Available We consider the problem of large-amplitude vibrations of a simply supported circular flat plate subjected to harmonically varying temperature fields arising from an external heat flux (aeroheating for example. The plate is modeled using the von Karman equations. We used the method of multiple scales to determine an approximate solution for the case in which the frequency of the thermal variations is approximately twice the fundamental natural frequency of the plate; that is, the case of principal parametric resonance. The results show that such thermal loads produce large-amplitude vibrations, with associated multi-valued responses and subcritical instabilities.
Finite Element Analysis of Circular Plate using SolidWorks
Energy Technology Data Exchange (ETDEWEB)
Kang, Yeo Jin; Jhung, Myung Jo [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)
2011-10-15
Circular plates are used extensively in mechanical engineering for nuclear reactor internal components. The examples in the reactor vessel internals are upper guide structure support plate, fuel alignment plate, lower support plate etc. To verify the structural integrity of these plates, the finite element analyses are performed, which require the development of the finite element model. Sometimes it is very costly and time consuming to make the model especially for the beginners who start their engineering job for the structural analysis, necessitating a simple method to develop the finite element model for the pursuing structural analysis. Therefore in this study, the input decks are generated for the finite element analysis of a circular plate as shown in Fig. 1, which can be used for the structural analysis such as modal analysis, response spectrum analysis, stress analysis, etc using the commercial program Solid Works. The example problems are solved and the results are included for analysts to perform easily the finite element analysis of the mechanical plate components due to various loadings. The various results presented in this study would be helpful not only for the benchmark calculations and results comparisons but also as a part of the knowledge management for the future generation of young designers, scientists and computer analysts
An Analysis of Elasto-Plastic Bending of Rectangular Plate
Matsuda, Hiroshi; Sakiyama, Takeshi
1988-01-01
In this paper, a discrete method for analyzing the problem of elasto-plastic bending of a rectangular plate is proposed. The solutions for partial differential equation of rectangular plate are obtained in discrete forms by applying numerical integnltion. An incremental variable elasticity procedure has been used for the clasta-plastic analysis of the rectangular plate. As the applications of the proposed method, clasta-plastic bending of rectangular plate with four types of boundary conditio...
Institute of Scientific and Technical Information of China (English)
丁皓江; 徐荣桥; 国凤林
1999-01-01
Emphasis is placed on purely elastic circular plates. Let the piezoelectric coefficients be equal to zero. Then two sets of uncoupled mechanical and electric equations are obtained and they can be solved independently. Two three-dimensional exact solutions of laminated transversely isotropic circular plate are derived under two boundary conditions, i.e. rigid slipping support and elastic simple support. For isotropic circular plates, the problem of multiple root is treated. At last, some numerical results of piezoelectric and purely elastic circular plates are presented and the applicability of classical plate theory is discussed.
Institute of Scientific and Technical Information of China (English)
丁皓江; 徐荣桥; 国凤林
1999-01-01
Based on three-dimensional elastic equations for piezoelectric materials, the state equations for piezoelectric circular plate under axisymmetric deformation are derived. Applying Hankel transform to them and letting the free boundary terms resulting from Hankel transform be zero, a set of ordinary differential equations with constant coefficients and associated boundary conditions are obtained. Furthermore, two exact solutions corresponding to generalized rigid slipping and generalized elastic simple support are deduced. Then, the governing equations obtained reduce to equations for axisymmetric problem of transversely isotropic circular plate. Under the two types of boundary conditions of elastic simple support and rigid slipping, exact solutions are derived. Finally, numerical results are presented and applicability of the classical plate theory is discussed.
Elastostatic bending of a bimaterial plate with a circular interface
Ogbonna, Nkem
2015-08-01
The elastostatic bending of an arbitrarily loaded bimaterial plate with a circular interface is analysed. It is shown that the deflections in the composite solid are directly related to the deflection in the corresponding homogeneous material by integral and differential operators. It is further shown that, by a simple transformation of elastic constants, the Airy stress function induced in the composite by a stretching singularity can be deduced from the deflection induced by a bending singularity. This result is significant for reduction of mathematical labour and for systematic construction of solutions for more complex structures with circular geometry.
Impact Damage of 3D Orthogonal Woven Composite Circular Plates
Ji, Changgan; Sun, Baozhong; Qiu, Yiping; Gu, Bohong
2007-11-01
The damages of 3D orthogonal woven composite circular plate under quasi-static indentation and transverse impact were tested with Materials Test System (MTS) and modified split Hopkinson bar (SHPB) apparatus. The load vs. displacement curves during quasi-static penetration and impact were obtained to study the energy absorption of the composite plate. The fluctuation of the impact stress waves has been unveiled. Differences of the load-displacement curves between the quasi-static and impact loading are discussed. This work also aims at establishing a unit-cell model to analyze the damage of composites. A user material subroutine which named VUMAT for characterizing the constitutive relationship of the 3-D orthogonal woven composite and the damage evolution is incorporated with a finite element code ABAQUS/Explicit to simulate the impact damage process of the composite plates. From the comparison of the load-displacement curves and energy absorption curves of the composite plate between experimental and FEM simulation, it is shown that the unit-cell model of the 3D woven composite and the VUMAT combined with the ABAQUS/Explicit can calculate the impact responses of the circular plate precisely. Furthermore, the model can also be extended to simulate the impact behavior of the 3D woven composite structures.
FINITE ELEMENT MODELING OF THIN CIRCULAR SANDWICH PLATES DEFLECTION
Directory of Open Access Journals (Sweden)
K. S. Kurachka
2014-01-01
Full Text Available A mathematical model of a thin circular sandwich plate being under the vertical load is proposed. The model employs the finite element method and takes advantage of an axisymmetric finite element that leads to the small dimension of the resulting stiffness matrix and sufficient accuracy for practical calculations. The analytical expressions for computing local stiffness matrices are found, which can significantly speed up the process of forming the global stiffness matrix and increase the accuracy of calculations. A software is under development and verification. The discrepancy between the results of the mathematical model and those of analytical formulas for homogeneous thin circularsandwich plates does not exceed 7%.
Inverse transient thermoelastic deformations in thin circular plates
Indian Academy of Sciences (India)
A K Tikhe; K C Deshmukh
2005-10-01
This paper deals with the determination of unknown heating temperatures and temperature distributions on the upper surface of a thin circular plate, deﬁned as $0 \\leq r \\leq a,−b/2 \\leq z \\leq b/2$. The expressions of unknown heating temperatures and temperature distributions are obtained in series form, involving Bessel’s functions with the help of the integral transform technique. Thermoelastic deformations are discussed with the help of temperature and are illustrated numerically.
On Dynamic Transmitting Property of Circular Plate MR Clutch
Guo, Chongzhi; Guo, Jiangchuan; Guo, Yu; Ma, Ziyang
This study focuses on the analysis of relationship between the current density and the torque of a circular plate Magneto-Rheological (MR) clutch. In order to get the expression of magnetic induction intensity, the Finite Element Method(FEM) is used for the magnetic analysis on the given geometry of circular plate MR clutch under different current density. With some reasonable assumptions, the discrete values of the magnetic induction intensity along some defined paths are obtained. The fitted expression of magnetic induction intensity is derived from discrete points and the analysis of these discrete data. Based on the expression and the Bingham model which is used to describe the constitutive characteristics of the MR fluids flow between two circular plates subject to an applied magnetic field induced by current density, the mathematical model to transmit the torque is established. From the model and the fit expression, the relationship of the torque and the current density is deduced. The numerical results show that the torque transferred under magnetic induction density by control current density is increased smoothly as the current density is increased except a very short time after initial start. Results also indicate that the torque can be controlled continuously by changing the current density. The analysis provides the theoretical foundation for the design of the MR clutch, and the equation of the torque provides the information by which the torque transmitted by the clutch can be manipulated accurately through adjusting the current density.
Displacements and stresses in bending of circular perforated plate
Atanasiu, C.; Sorohan, St.
2016-08-01
The flat plates, perforated by a large number of holes are widely used in the engineering, especially in the component of the process equipment. Strength calculations and experimental methods used in the actual literature for study perforated plates, do not present the problem in all its complexity for stress distribution and displacements. Research and doctoral theses in last decades, with methods characteristic of the respective periods were engaged either perforated plates considered infinite and requested the median plane or rarely, plate loaded normal to the median plane, with a small number of holes. In this work the stress distribution and displacement is presented for a circular plate perforated by 96 holes arranged in a grid of squares, simply supported on the outline and loaded through a central concentrated force or by uniformly distributed load. It conducted a numerical analysis by finite element method (FEM) with a proper meshing of the plate and an experimental study by holographic interferometry. Holographic interferometry method permits to measure, with high accuracy, extremely small displacements and comparing the results with those obtained by FEM becomes sustainable. Supplementary, an analysis of a non-perforated plate with the same dimensions and stiffness, similar loaded, was performed, determining the coefficient of stress concentration for a particular arrangement of holes.
Energy Technology Data Exchange (ETDEWEB)
Saeedi, Khodabakhsh; Bhat, Rama B.; Stiharu, Ion [Concordia University, Montreal (Canada); Leo, Alfin [2Parker Filtration Canada, Laval (Canada)
2012-05-15
The free vibration of a circular plate with multiple perforations is analyzed by using the Rayleigh-Ritz method. Admissible functions are assumed to be separable functions of radial and tangential coordinates. Trigonometric functions are assumed in the circumferential direction. The radial shape functions are the boundary characteristic orthogonal polynomials generated following the Gram-Schmidt recurrence scheme. The assumed functions are used to estimate the kinetic and the potential energies of the plate depending on the number and the position of the perforations. The eigenvalues, representing the dimensionless natural frequencies, are compared with the results obtained using Bessel functions, where the exact solution is available. Moreover, the eigenvectors, which are the unknown coefficients of the Rayleigh-Ritz method, are used to present the mode shapes of the plate. To validate the analytical results of the plates with multiple perforations, experimental investigations are also performed. Two unique case studies that are not addressed in the existing literature are considered. The results of the Rayleigh-Ritz method are found to be in good agreement with those from the experiments. Although the method presented can be employed in the vibration analysis of plates with different boundary conditions and shapes of the perforations, circular perforations that are free on the edges are studied in this paper. The results are presented in terms of dimensionless frequencies and mode shapes.
Elasto-plastic finite element analysis of squaring circular tube
Institute of Scientific and Technical Information of China (English)
HUANG Yuung-ming
2008-01-01
The flow rule of Prandtl-Reuss was adopted and incremental elasto-plastic finite-element analysis formulation of Coulomb's friction law combining the finite deformation theory was established,and Lagrangian formulation for simulating the squaring process of circular tube was updated.Incremental Coulomb's friction law was used in the global stiffness matrix to solve the sliding-sticking state of friction at the boundary contact interface.During the squaring process,the linear factor γmin was adopted to solve the non-linear boundary problems of changing node contact and separation,elasto-plastic transient situation in an element and the non-linear constitutive behavior of material so as to make each reasonable increment of the punch meet the demand of calculation for linear increment.The squaring process of circular tube,load distribution and final shape of work piece after unloading were simulated by this mode and compared with research data.It is known that the circular tube with higller geometrical ratio (R/t) could be pressed into symmetric square tube without collapse.This result can provide reference for the analysis of this process and evaluation and improvement of product defects.
Modal analysis of two identical circular plates coupled with fluid
Energy Technology Data Exchange (ETDEWEB)
Jeong, Kyeong Hoon; Lee, Gyu Mahn; Park, Keun Bae; Chang, Moon Hee
2001-01-01
An analytical method for evaluating the free vibration of two identical circular plates coupled with fluid was developed by assuming the clamped boundary condition of the plates and an ideal fluid. The method was based upon the finite Fourier-Bessel series expansion and the Rayleigh-Riz method. The proposed method is verified by finite element analyses using commercial software, ANSYS (release 5.6) with good accuracy. Two transverse vibration modes, namely in-phase and out-of-phase, are observed alternately in the fluid-coupled system when the number of nodal circles increases for the fixed nodal diameter. It is found that the normalized natural frequency of the fluid-coupled system monotonically increases with an increase in the number of nodal diameters and circles by virtue of a decrease in relative hydrodynamic mass. The effect of distance between the circular plates and the effect of fluid bounding on the fluid-coupled natural frequencies are also investigated. The theory developed in this report can be applicable to the dynamic analysis of a bottom screen assembly in SMART integral reactor.
Numerical simulation of droplet evaporation between two circular plates
Energy Technology Data Exchange (ETDEWEB)
Bam, Hang Jin; Son, Gi Hun [Sogang University, Seoul (Korea, Republic of)
2015-06-15
Numerical simulation is performed for droplet evaporation between two circular plates. The flow and thermal characteristics of the droplet evaporation are numerically investigated by solving the conservation equations of mass, momentum, energy and mass fraction in the liquid and gas phases. The liquid-gas interface is tracked by a sharp-interface level-set method which is modified to include the effects of evaporation at the liquid-gas interface and contact angle hysteresis at the liquid-gas-solid contact line. An analytical model to predict the droplet evaporation is also developed by simplifying the mass and vapor fraction equations in the gas phase. The numerical results demonstrate that the 1-D analytical prediction is not applicable to the high rate evaporation process. The effects of plate gap and receding contact angle on the droplet evaporation are also quantified.
Improving the circular economy via hydrothermal processing of highdensity waste plastics
DEFF Research Database (Denmark)
Pedersen, Thomas Helmer; Conti, Federica
2017-01-01
Rising environmental concerns on climate changes are causing an increasing attention on circular economies. The plastic economy, in particular, is in focus due to the accelerating consumption of plastics, mainly derived from virgin feedstock, combined with the lack of plastic recycling strategies....... This work presents a novel outlook on the potential of using supercritical hydrothermal processing of waste plastic fractions for tertiary recycling. The study investigates hydrothermal processing of nine different, high-density types of plastics into original resin monomers and other value-added chemical...... processing of high-density plastics is a prospective technology for increasing the circularity of the plastic economy....
Elasto-plastic postbuckling of damaged orthotropic plates
Institute of Scientific and Technical Information of China (English)
TIAN Yan-ping; FU Yi-ming
2008-01-01
Based on the elasto-plastic mechanics and continuum damage theory, a yield criterion related to spherical tensor of stress is proposed to describe the mixed hardening of damaged orthotropic materials. Its dimensionless form is isomorphic with the Mises criterion for isotropic materials. Furthermore, the incremental elasto-plastic damage constitutive equations and damage evolution equations are established. Based on the classical nonlinear plate theory, the incremental nonlinear equilibrium equations of orthotropic thin plates considering damage effect are obtained, and solved with the finite difference and iteration methods. In the numerical examples, the effects of damage evolution and initial deflection on the elasto-plastic postbuckling of orthotropic plates are discussed in detail.
Effect of plasma actuator and splitter plate on drag coefficient of a circular cylinder
Directory of Open Access Journals (Sweden)
Akbıyık Hürrem
2016-01-01
Full Text Available In this paper, an experimental study on flow control around a circular cylinder with splitter plate and plasma actuator is investigated. The study is performed in wind tunnel for Reynolds numbers at 4000 and 8000. The wake region of circular cylinder with a splitter plate is analyzed at different angles between 0 and 180 degrees. In this the study, not only plasma actuators are activated but also splitter plate is placed behind the cylinder. A couple electrodes are mounted on circular cylinder at ±90 degrees. Also, flow visualization is achieved by using smoke wire method. Drag coefficient of the circular cylinder with splitter plate and the plasma actuator are obtained for different angles and compared with the plain circular cylinder. While attack angle is 0 degree, drag coefficient is decreased about 20% by using the splitter plate behind the circular cylinder. However, when the plasma actuators are activated, the improvement of the drag reduction is measured to be 50%.
Analytical solutions of simply supported magnetoelectroelastic circular plate under uniform loads
Institute of Scientific and Technical Information of China (English)
陈江英; 丁皓江; 侯鹏飞
2003-01-01
In this paper, the axisymmetric general solutions of transversely isotropic magnetoelectroelastic media are expressed with four harmonic displacement functions at first. Then, based on the solutions, the analytical three-dimensional solutions are provided for a simply supported magnetoelectroelastic circular plate subjected to uniform loads. Finally, the example of circular plate is presented.
Forced Response of Polar Orthotropic Tapered Circular Plates Resting on Elastic Foundation
Directory of Open Access Journals (Sweden)
A. H. Ansari
2016-01-01
Full Text Available Forced axisymmetric response of polar orthotropic circular plates of linearly varying thickness resting on Winkler type of elastic foundation has been studied on the basis of classical plate theory. An approximate solution of problem has been obtained by Rayleigh Ritz method, which employs functions based upon the static deflection of polar orthotropic circular plates. The effect of transverse loadings has been studied for orthotropic circular plate resting on elastic foundation. The transverse deflections and bending moments are presented for various values of taper parameter, rigidity ratio, foundation parameter, and flexibility parameter under different types of loadings. A comparison of results with those available in literature shows an excellent agreement.
Institute of Scientific and Technical Information of China (English)
Bahattin Kanber; O.Yavuz Bozkurt
2006-01-01
In this work,the finite element analysis of the elasto-plastic plate bending problems is carried out using transition rectangular plate elements.The shape functions of the transition plate elements are derived based on a practical rule.The transition plate elements are all quadrilateral and can be used to obtain efficient finite element models using minimum number of elements.The mesh convergence rates of the models including the transition elements are compared with the regular element models.To verify the developed elements,simple tests are demonstrated and various elasto-plastic problems are solved.Their results are compared with ANSYS results.
Capacity of the circular plate condenser: analytical solutions for large gaps between the plates
Rao, T. V.
2005-11-01
A solution of Love's integral equation (Love E R 1949 Q. J. Mech. Appl. Math. 2 428), which forms the basis for the analysis of the electrostatic field due to two equal circular co-axial parallel conducting plates, is considered for the case when the ratio, τ, of distance of separation to radius of the plates is greater than 2. The kernel of the integral equation is expanded into an infinite series in odd powers of 1/τ and an approximate kernel accurate to {\\cal O}(\\tau^{-(2N+1)}) is deduced therefrom by terminating the series after an arbitrary but finite number of terms, N. The approximate kernel is rearranged into a degenerate form and the integral equation with this kernel is reduced to a system of N linear equations. An explicit analytical solution is obtained for N = 4 and the resulting analytical expression for the capacity of the circular plate condenser is shown to be accurate to {\\cal O}(\\tau^{-9}) . Analytical expressions of lower orders of accuracy with respect to 1/τ are deduced from the four-term (i.e., N = 4) solution and predictions (of capacity) from the expressions of different orders of accuracy (with respect to 1/τ) are compared with very accurate numerical solutions obtained by solving the linear system for large enough N. It is shown that the {\\cal O}(\\tau^{-9}) approximation predicts the capacity extremely well for any τ >= 2 and an {\\cal O}(\\tau^{-3}) approximation gives, for all practical purposes, results of adequate accuracy for τ >= 4. It is further shown that an approximate solution, applicable for the case of large distances of separation between the plates, due to Sneddon (Sneddon I N 1966 Mixed Boundary Value Problems in Potential Theory (Amsterdam: North-Holland) pp 230-46) is accurate to {\\cal O}(\\tau^{-6}) for τ >= 2.
Institute of Scientific and Technical Information of China (English)
Zhongsheng Chen; Xin Tang; Zheng Hu; Yongmin Yang
2014-01-01
Circular thin-plate electrostatic sensors are promising in gas path monitoring due to their advantages of non-intrusiveness and easy installation. The spatial sensitivity and filtering effect are two important performance parameters. In this paper, an analytically mathematical model of induced charge on a circular thin-plate electrode is first derived. Then the spatial sensitivity and fil-tering effect of the circular electrostatic sensor are investigated by numerical calculations. Finally, experimental studies are performed to testify the theoretical results. Both theoretical and experimen-tal results demonstrate that circular thin-plate electrostatic sensors act as a low-pass filter in the spa-tial frequency domain, and both the spatial filtering effect and the temporal frequency response characteristics depend strongly on the spatial position and velocity of the charged particle. These conclusions can provide guidelines for the optimal design of circular thin-plate electrostatic sensors.
Non-linear resonances in the forced responses of plates. I - Symmetric responses of circular plates
Sridhar, S.; Mook, D. T.; Nayfeh, A. H.
1975-01-01
The dynamic analogue of the von Karman equations is used to study the symmetric response of a circular plate to a harmonic excitation when the frequency of the excitation is near one of the natural frequencies. It is shown that, in general, when there is no internal resonance (i.e., the natural frequencies are not commensurable), only the mode having a frequency near that of the excitation is strongly excited (i.e., is needed to represent the response in the first approximation). A clamped, circular plate is used as a numerical example to show that, when there is an internal resonance, more than one of the modes involved in this resonance can be strongly excited; moreover, when more than one mode is strongly excited, the lower modes can dominate the response, even when the frequency of the excitation is near that of the highest mode. This possibility was not revealed by any of the earlier studies which were based on the same governing equations.
Electrostatic and Small-Signal Analysis of CMUTs With Circular and Square Anisotropic Plates.
Funding la Cour, Mette; Christiansen, Thomas Lehrmann; Jensen, Jørgen Arendt; Thomsen, Erik Vilain
2015-08-01
Traditionally, capacitive micromachined ultrasonic transducers (CMUTs) are modeled using the isotropic plate equation, and this leads to deviations between analytical calculations and finite element modeling (FEM). In this paper, the deflection is calculated for both circular and square plates using the full anisotropic plate equation. It is shown that the anisotropic calculations match excellently with FEM, whereas an isotropic approach causes up to 10% deviations in deflection. For circular plates, an exact solution can be found. For square plates using the Galerkin method, and utilizing the symmetry of the silicon crystal, a compact and accurate expression for the deflection can be obtained. The deviation from FEM in center deflection is white light interferometer. Fitting the plate parameter for the anisotropic calculated deflection to the measurement, a deviation of 0.07% is seen. Electrostatic and small-signal dynamic analysis are performed using energy considerations including anisotropy. The stable position, effective spring constant, pullin distance, and pull-in voltage are found for both circular and square anisotropic plates, and the pressure dependence is included by comparison with the corresponding analysis for a parallel plate. Measurements on fabricated devices with both circular and square plates subjected to increasing bias voltage are performed, and it is observed that the models including anisotropic effects are within the uncertainty interval of the measurements. Finally, a lumped element small-signal model for both circular and square anisotropic plates is derived to describe the dynamics of the CMUT.
Fan, Tao; Zou, Guangping
2012-04-01
In this paper, the variational principle of functionally graded circular plate is presented by the variational integral method taking temperature change into account. The vibration governing equation is illustrated, which will be benefit for the numerical simulation with finite element method in further investigations. The numerical results show that the natural frequency increases as the graded coefficient increases in the chosen domain. It can be observed that the vibration characteristics are influenced by the temperature changes obviously. Moreover, the natural frequency is larger for thicker FGM circular plates, while it is lower for thinner ones. Furthermore, the first four vibration mode shapes with different thickness of FGM circular plate are illustrated.
A unified theory of plastic buckling of columns and plates
Stowell, Elbridge Z
1948-01-01
On the basis of modern plasticity considerations, a unified theory of plastic buckling applicable to both columns and plates has been developed. For uniform compression, the theory shows that long columns which bend without appreciable twisting require the tangent modulus and that long flanges which twist without appreciable bending require the secant modulus. Structures that both bend and twist when they buckle require a modulus which is a combination of the secant modulus and the tangent modulus. (author)
The New Plating Process on Plastics
Institute of Scientific and Technical Information of China (English)
MakotoImamura; JunOkada; KazuyaSatoh
2004-01-01
This process does not use general electroless plating solution containing formaldehyde(carcinogen) and phosphate(the object of waste water regulation). Furthermore. we succeeded in developing a new electroless copper plating solution which is usable semi-permanently by using the special reducing agent, The electroless deposition forms a very thin conductive film on substrate. Therefore, it can prevent some appearance defects (e.g. pits. pin-holes, laminations and inclusions) that occur in the conventional ones. In addition, it is possible to eliminate electroplating of copper from the process by applying the exclusive nickel solution in electroplating. Therefore, the obtained metal parts can be recycled as high quality stainless steel. Given this copper elecltoplating-free process, 25μ m-thick nickel deposition at the stage of electroplating, at least, enables the metal layers to show properties as versatile as those of the conventional(its total thickness is 25μm in the comparative conventional process).
The New Plating Process on Plastics
Institute of Scientific and Technical Information of China (English)
Makoto Imamura; Jun Okada; Kazuya Satoh
2004-01-01
This process does not use general electroless plating solution containing formaldehyde(carcinogen) and phosphate(the object of waste water regulation). Furthermore, we succeeded in developing a new electroless copper plating solution which is usable semi-permanently by using the special reducing agent. The electroless deposition forms a very thin conductive film on substrate. Therefore, it can prevent some appearance defects (e.g. pits, pin-holes, laminations and inclusions) that occur in the conventional ones. In addition, it is possible to eliminate electroplating of copper from the process by applying the exclusive nickel solution in electroplating. Therefore, the obtained metal parts can be recycled as high quality stainless steel. Given this copper electroplating-free process, 25μ m-thick nickel deposition at the stage of electroplating, at least, enables the metal layers to show properties as versatile as those of the conventional(its total thickness is 25μ m in the comparative conventional process).
Directory of Open Access Journals (Sweden)
C. M. Bhongade
2014-09-01
Full Text Available The present paper deals with the determination of displacement and thermal transient stresses in a thick circular plate with internal heat generation. External arbitrary heat supply is applied at the upper surface of a thick circular plate, whereas the lower surface of a thick circular plate is insulated and heat is dissipated due to convection in surrounding through lateral surface. Here we compute the effects of internal heat generation of a thick circular plate in terms of stresses along radial direction. The governing heat conduction equation has been solved by using integral transform method. The results are obtained in series form in terms of Bessel’s functions and the results for temperature change and stresses have been computed numerically and illustrated graphically.
Institute of Scientific and Technical Information of China (English)
LI Xiang-yu; DING Hao-jiang; CHEN Wei-qiu
2006-01-01
This paper considers the pure bending problem of simply supported transversely isotropic circular plates with elastic compliance coefficients being arbitrary functions of the thickness coordinate. First, the partial differential equation, which is satisfied by the stress functions for the axisymmetric deformation problem is derived. Then, stress functions are obtained by proper manipulation. The analytical expressions of axial force, bending moment and displacements are then deduced through integration.And then, stress functions are employed to solve problems of transversely isotropic functionally graded circular plate, with the integral constants completely determined from boundary conditions. An elasticity solution for pure bending problem, which coincides with the available solution when degenerated into the elasticity solutions for homogenous circular plate, is thus obtained.A numerical example is finally presented to show the effect of material inhomogeneity on the elastic field in a simply supported circular plate of transversely isotropic functionally graded material (FGM).
Electrostatic and Small-Signal Analysis of CMUTs With Circular and Square Anisotropic Plates
DEFF Research Database (Denmark)
la Cour, Mette Funding; Christiansen, Thomas Lehrmann; Jensen, Jørgen Arendt
2015-01-01
Traditionally, Capacitive Micromachined Ultrasonic Transducers (CMUTs) are modeled using the isotropic plate equation and this leads to deviations between analytical calcu- lations and Finite Element Modeling (FEM). In this paper, the deflection is calculated for both circular and square plates...... using the full anisotropic plate equation. It is shown that the anisotropic calculations match perfectly with FEM while an isotropic ap- proach causes up to 10% deviations in deflection. For circular plates an exact solution can be found and for square plates using the Galerkin method and utilizing...... the symmetry of the silicon crystal, a compact and accurate expression for the deflection can be obtained. The deviation from FEM in center deflection is plates is also applied to the CMUT. The deflection of a square plate was measured on fabricated CMUTs using a white light...
Nonlinear vibration and buckling of circular sandwich plate under complex load
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
The nonlinear vibration fundamental equation of circular sandwich plate under uniformed load and circumjacent load and the loosely clamped boundary condition were established by von Karman plate theory, and then accordingly exact solution of static load and its numerical results were given. Based on time mode hypothesis and the variational method, the control equation of the space mode was derived, and then the amplitude frequency-load character relation of circular sandwich plate was obtained by the modified iteration method. Consequently the rule of the effect of the two kinds of load on the vibration character of the circular sandwich plate was investigated. When circumjacent load makes the lowest natural frequency zero, critical load is obtained.
Thin circular plate uniformaly loaded over a concentric elliptic path and supported on columns
Directory of Open Access Journals (Sweden)
W. A. Bassali
1986-01-01
Full Text Available Within the limitations of the classical thin plate theory expressions are obtained for the small deflections of a thin isotropic circular plate uniformly loaded over a concentric ellipse and supported by four columns at the vertices of a rectangle whose sides are parallel to the axes of the ellipse. Formulae are given for the moments and shears at the centre of the plate and on the edge. Limiting cases are investigated.
Institute of Scientific and Technical Information of China (English)
侯朝胜; 李婧; 龙泉
2003-01-01
The cubic B-splines taken as trial function, the large deflection of a circular plate with arbitrarily variable thickness,as well as the buckling load, have been calculated by the method of point collocation. The support can be elastic. Loads imposed can be polynomial distributed loads, uniformly distributed radial forces or moments along the edge respectively or their combinations. Convergent solutions can still be obtained by this method under the load whose value is in great excess of normal one. Under the action of the uniformly distributed loads, linear solutions of circular plates with linearly or quadratically variable thickness are compared with those obtained by the parameter method. Buckling of a circular plate with identical thickness beyond critical thrust is compared with those obtained by the power series method.
Studies on the Dynamic Buckling of Circular Plate Irradiated by Laser Beam
Institute of Scientific and Technical Information of China (English)
黄晨光; 段祝平
2002-01-01
The dynamic buckling of thin copper plate induced by laser beam, was analyzed with the numerical integration and disturbance methods of controlling equation. The buckling and post-buckling of thin plate were shown, with the consideration of the temperature distribution, inertia effect and initial deflection. At last, the buckling criterion about the circular plate was obtained and used to investigate the relation between the critical laser intensity and the ratio of thickness and diameter of the plate. The results fit the experimental observation and the FEM simulation very well, and benefit to the understanding of failure phenomenon of structures irradiated by laser beam.
Nonlinear Resonance of the Rotating Circular Plate under Static Loads in Magnetic Field
Institute of Scientific and Technical Information of China (English)
HU Yuda; WANG Tong
2015-01-01
The rotating circular plate is widely used in mechanical engineering, meanwhile the plates are often in the electromagnetic field in modern industry with complex loads. In order to study the resonance of a rotating circular plate under static loads in magnetic field, the nonlinear vibration equation about the spinning circular plate is derived according to Hamilton principle. The algebraic expression of the initial deflection and the magneto elastic forced disturbance differential equation are obtained through the application of Galerkin integral method. By mean of modified Multiple scale method, the strongly nonlinear amplitude-frequency response equation in steady state is established. The amplitude frequency characteristic curve and the relationship curve of amplitude changing with the static loads and the excitation force of the plate are obtained according to the numerical calculation. The influence of magnetic induction intensity, the speed of rotation and the static loads on the amplitude and the nonlinear characteristics of the spinning plate are analyzed. The proposed research provides the theory reference for the research of nonlinear resonance of rotating plates in engineering.
THICKNESS-SHEAR VIBRATION OF CIRCULAR CRYSTAL PLATE IN CYLINDRICAL SHELL AS PRESSURE SENSOR
Institute of Scientific and Technical Information of China (English)
HU Yuan-tai; CUI Zhi-jian; JIANG Shu-nong; YANG Jia-shi
2006-01-01
Based on the theory for small fields superposed on relatively larger fields in an electroelastic body, a theoretical analysis is performed on a circular plate thicknessshear crystal resonator sealed in a circular cylindrical shell for pressure measurement.A simple expression is obtained for pressure induced frequency shifts in the resonator,which is examined for design optimization. Numerical results show that the frequency shifts depend linearly on the pressure, and that a pressure sensor with a softer outer shell or a smaller thickness ratio of the crystal plate to the outer shell has higher sensitivity.
Spin-Hall effect and circular birefringence of a uniaxial crystal plate
Bliokh, K Y; Prajapati, C; Puentes, G; Viswanathan, N K; Nori, F
2016-01-01
The linear birefringence of uniaxial crystal plates is known since the 17th century. Here we demonstrate, both theoretically and experimentally, a fine lateral circular birefringence of such crystal plates. We show that this effect is a novel example of the spin-Hall effect of light, i.e., a transverse spin-dependent shift of the paraxial light beam transmitted through the plate. The well-known linear birefringence and the new circular birefringence form an interesting analogy with the Goos-Hanchen and Imbert-Fedorov beam shifts that appear in the light reflection at a dielectric interface. We report the experimental observation of the effect in a remarkably simple system of a tilted half-wave plate and polarizers using polarimetric and quantum-weak-measurement techniques for the beam-shift measurements.
Flat Plate Wake Velocity Statistics Obtained With Circular And Elliptic Trailing Edges
Rai, Man Mohan
2016-01-01
The near wake of a flat plate with circular and elliptic trailing edges is investigated with data from direct numerical simulations. The plate length and thickness are the same in both cases. The separating boundary layers are turbulent and statistically identical. Therefore the wake is symmetric in the two cases. The emphasis in this study is on a comparison of the wake-distributions of velocity components, normal intensity and fluctuating shear stress obtained in the two cases.
Thermal deformation in a thin circular plate due to a partially distributed heat supply
Indian Academy of Sciences (India)
N L Khobragade; K C Deshmukh
2005-08-01
In this paper, we develop an integral transform to determine temperature distribution in a thin circular plate, subjected to a partially distributed and axisymmetric heat supply on the curved surface, and study the thermal deformation. The results, obtained in series form in terms of Bessel’s functions, are illustrated numerically.
CUBLIC SPLINE SOLUTIONS OF AXISYMMETRICAL NONLINEAR BENDING AND BRCKLING OF CIRCULAR SANDWICH PLATES
Institute of Scientific and Technical Information of China (English)
侯朝胜; 张守恺; 林锋
2005-01-01
Cubic B-spline taken as trial function, the nonlinear bending of a circular sandwich plate was calculated by the method of point collocation. The support could be elastic. A sandwich plate was assumed to be Reissner model. The formulae were developed for the calculation of a circular sandwich plate subjected to polynomial distributed loads,uniformly distributed moments, radial pressure or radial prestress along the edge and their combination. Buckling load was calculated for the first time by nonlinear theory. Under action of uniformly distributed loads, results were compared with that obtained by the power series method. Excellences of the program written by the spline collocation method are wide convergent range, high precision and universal.
Interaction of circular cylinder wake with a short asymmetrically located downstream plate
Yucel, S. B.; Cetiner, O.; Unal, M. F.
2010-07-01
This study reveals the interaction patterns of separated shear layers from a circular cylinder with a short downstream plate and their reflection on the frequency and the formation length of the vortices from the cylinder as a function of plate location relative to the cylinder. The effect of horizontal ( G/D) and vertical ( Z/D) distances between the cylinder and the plate on the near wake is studied via Digital Particle Image Velocimetry (DPIV) in a water channel for Reynolds numbers of 200, 400 and 750, based on the cylinder diameter D. It is shown that the interaction of wake with the plate of length D can be categorized depending on the horizontal and the vertical distances between the cylinder and the plate. For the vertical distance range of Z/D ≤ 0.7, there is a critical horizontal spacing before which the shear layers from the cylinder are inhibited to form vortices in front of the plate. Resulting elongated recirculation region between the plate and the cylinder suggests modification of the absolutely unstable near wake of free circular cylinder in favor of convective instability. Z/D = 0.9 provides a passage from Z/D ≤ 0.7 to ≥1.1 and is associated with a dominant effect on the near-wake characteristics of interaction of shear layers from the cylinder with those from the downstream plate. For Z/D ≥ 1.1, there is again, yet a smaller critical horizontal spacing after which vortices interact with decreased downstream plate interference. In this vertical separation distance range, a gap flow between the plate and the cylinder plays a determining role on the formation length and St number of vortices for small horizontal spacing values.
Uniform electric field generation in circular multi-well culture plates using polymeric inserts
Tsai, Hsieh-Fu; Cheng, Ji-Yen; Chang, Hui-Fang; Yamamoto, Tadashi; Shen, Amy Q.
2016-01-01
Applying uniform electric field (EF) in vitro in the physiological range has been achieved in rectangular shaped microchannels. However, in a circular-shaped device, it is difficult to create uniform EF from two electric potentials due to different electrical resistances originated from the length difference between the diameter of the circle and the length of any parallel chord of the bottom circular chamber where cells are cultured. To address this challenge, we develop a three-dimensional (3D) computer-aided designed (CAD) polymeric insert to create uniform EF in circular shaped multi-well culture plates. A uniform EF with a coefficient of variation (CV) of 1.2% in the 6-well plate can be generated with an effective stimulation area percentage of 69.5%. In particular, NIH/3T3 mouse embryonic fibroblast cells are used to validate the performance of the 3D designed Poly(methyl methacrylate) (PMMA) inserts in a circular-shaped 6-well plate. The CAD based inserts can be easily scaled up (i.e., 100 mm dishes) to further increase effective stimulation area percentages, and also be implemented in commercially available cultureware for a wide variety of EF-related research such as EF-cell interaction and tissue regeneration studies. PMID:27193911
Uniform electric field generation in circular multi-well culture plates using polymeric inserts
Tsai, Hsieh-Fu; Cheng, Ji-Yen; Chang, Hui-Fang; Yamamoto, Tadashi; Shen, Amy Q.
2016-05-01
Applying uniform electric field (EF) in vitro in the physiological range has been achieved in rectangular shaped microchannels. However, in a circular-shaped device, it is difficult to create uniform EF from two electric potentials due to different electrical resistances originated from the length difference between the diameter of the circle and the length of any parallel chord of the bottom circular chamber where cells are cultured. To address this challenge, we develop a three-dimensional (3D) computer-aided designed (CAD) polymeric insert to create uniform EF in circular shaped multi-well culture plates. A uniform EF with a coefficient of variation (CV) of 1.2% in the 6-well plate can be generated with an effective stimulation area percentage of 69.5%. In particular, NIH/3T3 mouse embryonic fibroblast cells are used to validate the performance of the 3D designed Poly(methyl methacrylate) (PMMA) inserts in a circular-shaped 6-well plate. The CAD based inserts can be easily scaled up (i.e., 100 mm dishes) to further increase effective stimulation area percentages, and also be implemented in commercially available cultureware for a wide variety of EF-related research such as EF-cell interaction and tissue regeneration studies.
Process of direct copper plating on ABS plastics
Energy Technology Data Exchange (ETDEWEB)
Wang Guixiang [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)]. E-mail: wgx0357@126.com; Li Ning [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Hu Huili [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Yu Yuanchun [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)
2006-11-15
The processes of direct copper plating on ABS plastics were investigated by atomic force microscopy (AFM), ultraviolet-visible absorption spectrometry (UV-vis) and X-ray fluorescence spectroscopy (XRF) techniques. The substrates were etched by CrO{sub 3}/H{sub 2}SO{sub 4} solution containing Pd{sup 2+} ions, catalyzed by Pd/Sn colloids solution and accelerated in an alkaline solution containing copper ions. The Pd{sup 2+} ions in etching solution can reduce the surface roughness and enhance the colloids adsorption. The good dispersivity colloids have excellent catalysis and its UV-vis peaks broaden. After acceleration, when the stability of Cu{sup 2+}-complex is relatively low, Sn{sup 2+} was oxidized by Cu{sup 2+} in the alkaline solution meanwhile Cu{sub 2}O can be formed. The disproportionation reaction of Cu{sub 2}O will proceed and metallic copper forms between the Pd particles, so the conductivity of ABS surface increased. The copper particles play an important role in determining the uniformity of the propagation of copper plating. The particles of copper plating layer were uniformity and fine. The atomic concentration and the thickness of copper layer were analyzed by XRF.
Ashoori, A. R.; Vanini, S. A. Sadough; Salari, E.
2017-04-01
In the present paper, vibration behavior of size-dependent functionally graded (FG) circular microplates subjected to thermal loading are carried out in pre/post-buckling of bifurcation/limit-load instability for the first time. Two kinds of frequently used thermal loading, i.e., uniform temperature rise and heat conduction across the thickness direction are considered. Thermo-mechanical material properties of FG plate are supposed to vary smoothly and continuously throughout the thickness based on power law model. Modified couple stress theory is exploited to describe the size dependency of microplate. The nonlinear governing equations of motion and associated boundary conditions are extracted through generalized form of Hamilton's principle and von-Karman geometric nonlinearity for the vibration analysis of circular FG plates including size effects. Ritz finite element method is then employed to construct the matrix representation of governing equations which are solved by two different strategies including Newton-Raphson scheme and cylindrical arc-length method. Moreover, in the following a parametric study is accompanied to examine the effects of the several parameters such as material length scale parameter, temperature distributions, type of buckling, thickness to radius ratio, boundary conditions and power law index on the dimensionless frequency of post-buckled/snapped size-dependent FG plates in detail. It is found that the material length scale parameter and thermal loading have a significant effect on vibration characteristics of size-dependent circular FG plates.
Rigid-Plastic Post-Buckling Analysis of Columns and Quadratic Plates
DEFF Research Database (Denmark)
Jönsson, Jeppe
2008-01-01
The objective of this paper is to show the application of a novel approach to the rigid plastic hinge and yield line theory in post-buckling analysis of slender plates and columns. The upper bound theorem of plasticity theory and the associated flow law of plasticity are used to find...... of the post-buckling behaviour. The rigid plastic theory of plates, referred to as yield line theory, involves large rigid parts of the plate mutually rotating about yielding hinge lines, however in order to accommodate in plane plastic deformations area “collapse” yield lines have been introduced. The hinge...... yield lines accommodate differential rotations of rigid parts and the area “collapse” yield lines accommodate local area changes of the rigid parts thereby preserving compatibility of the rigid parts of a plate. The approach will be illustrated for rigid plastic column analysis and for a quadratic plate...
AXISYMMETRIC BENDING OF TWO-DIRECTIONAL FUNCTIONALLY GRADED CIRCULAR AND ANNULAR PLATES
Institute of Scientific and Technical Information of China (English)
Guojun Nie; Zheng Zhong
2007-01-01
Assuming the material properties varying with an exponential law both in the thickness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using the semi-analytical numerical method in this paper. The deflections and stresses of the plates are presented. Numerical results show the well accuracy and convergence of the method. Compared with the finite element method, the semi-analytical numerical method is with great advantage in the computational efficiency. Moreover, study on axisymmetric bending of two-directional functionally graded annular plate shows that such plates have better performance than those made of isotropic homogeneous materials or one-directional functionally graded materials. Two-directional functionally graded material is a potential alternative to the one-directional functionally graded material. And the integrated design of materials and structures can really be achieved in two-directional functionally graded materials.
Constitutive Laws for Visco-plastic Porous Medium Shaped by Regularly Distributed Circular Particles
Institute of Scientific and Technical Information of China (English)
Yunzhu Cai; Huaicui Li
2016-01-01
A numerical study is presented, using a homogenization technique to consider the plain strain problem of visco⁃plastic porous medium shaped by regularly distributed circular particles. Based on a rigid plastic material, the paper derives the macroscopic constitutive laws for homogenous equivalent medium. By changing the shape parameter of circular particles, the effect of pore shape on macroscopic constitutive laws is explored. Yield surfaces with different pore shapes are obtained. About voids, a two⁃scale conception is introduced, which regards main void as macroscopic scale and secondary cavities as microscopic scale. The macroscopic potential involving main and secondary voids is achieved. The proposed macroscopic constitutive law taking microscopic features as influence factors is helpful for exploring the macroscopic mechanical properties of porous medium when numerical simulation is required.
Directory of Open Access Journals (Sweden)
Azatyan G.L.
2012-06-01
Full Text Available Asymptotic integration of the equations of three-dimensional problems of the theory electroelasticity derived recurrence formulas for determining the components of the stress tensor, displacement vector and electric potential of the plate of infinite longitudinal size with a circular aperture of inhomogeneous in terms of piezoelectric ceramics. The plate is polarized by thickness. Examined cases in which its front surfaces are given electric potentials together with the terms of the first, second or mixed boundary value problems of elasticity theory.
Directory of Open Access Journals (Sweden)
N. Bhardwaj
2012-01-01
Full Text Available Two dimensional boundary characteristic orthonormal polynomials are used in the Ritz method for the vibration analysis of clamped and simply-supported circular plates of varying thickness. The thickness variation in the radial direction is linear whereas in the circumferential direction the thickness varies according to cos kθ, where k is an integer. In order to verify the validity, convergence and accuracy of the results, comparison studies are made against existing results for the special case of linearly tapered thickness plates. Variations in frequencies for the first six normal modes of vibration and mode shapes for various taper parameters are presented.
Axisymmetrical Nonlinear Bending and Buckling of a Circular Plate Under Large Load
Institute of Scientific and Technical Information of China (English)
HOU Chaosheng; YUE Yanling
2005-01-01
With the terms of the exact series solution taken as trial functions, the method of point collocation was used to calculate the large deflection of a circular plate. The axisymmetrical bending formulae were developed for the calculation of a circular plate subjected to polynomial distributed loads, a concentrated load at the center, uniform radial forces and moments along the edge or their combinations. The support may be elastic. The buckling load was calculated. Under action of uniformly distributed load, central load or their compound load, solutions were compared with those obtained by other methods. Buckling beyond critical thrust was compared with that calculated by the power series method. The method presented in this paper has advantages of wide convergent range, high precision and short computing time. Moreover, the computing time is nearly independent of the complexity of the loads.
UNSYMMETRICAL NONLINEAR BENDING PROBLEM OF CIRCULAR THIN PLATE WITH VARIABLE THICKNESS
Institute of Scientific and Technical Information of China (English)
WANG Xin-zhi; ZHAO Yong-gang; JU Xu; ZHAO Yan-ying; YEH Kai-yuan
2005-01-01
Firstly, the cross large deflection equation of circular thin plate with variable thickness in rectangular coordinates system was transformed into unsymmetrical large deflection equation of circular thin plate with variable thickness in polar coordinates system.This cross equation in polar coordinates system is united with radical and tangential equations in polar coordinates system, and then three equilibrium equations were obtained. Physical equations and nonlinear deformation equations of strain at central plane are substituted into superior three equilibrium equations, and then three unsymmetrical nonlinear equations with three deformation displacements were obtained. Solution with expression of Fourier series is substituted into fundamental equations; correspondingly fundamental equations with expression of Fourier series were obtained. The problem was solved by modified iteration method under the boundary conditions of clamped edges. As an example, the problem of circular thin plate with variable thickness subjected to loads with cosin form was studied.Characteristic curves of the load varying with the deflection were plotted. The curves vary with the variation of the parameter of variable thickness. Its solution is accordant with physical conception.
Bulging Modes of Circular Bottom Plates in Rigid Cylindrical Containers Filled with a Liquid
Directory of Open Access Journals (Sweden)
Marco Amabili
1997-01-01
Full Text Available In this article the free vibrations of the bottom plate of an otherwise rigid circular cylindrical tank filled with liquid are studied, considering only the bulging modes (when the amplitude of the plate displacement is predominant with respect to that of the free surface. The tank axis is vertical, thus the free liquid surface is orthogonal to the tank axis. The liquid is assumed to be inviscid, and the contribution of the free surface waves to the dynamic pressure on the free liquid surface is neglected. Wet and dry mode shapes of the plate are assumed to be the same, so that the natural frequencies are obtained by using the nondimensionalized added virtual mass incremental (NA VMI factors and the modal properties of dry plates. This simplifies computations compared to other existing theoretical approaches. NAVMI factors express the nondimensionalized ratio between the reference kinetic energy of the liquid and that of the plate and have the advantage that, due to their nondimensional form, they can be computed once and for all. Numerical results for simply supported and clamped bottom plates, as well as for supported plates with an elastic moment edge constraint are given. For more accurate results, and to exceed the limits of the assumed modes approach, the Rayleigh-Ritz method is applied and results are compared to those obtained by using the NAVMI factors and other existing methods in the literature.
Asymmetric Vibrations of a Circular Elastic Plate on an Elastic Half Space
DEFF Research Database (Denmark)
Schmidt, H.; Krenk, Steen
1982-01-01
The asymmetric problem of a vibrating circular elastic plate in frictionless contact with an elastic half space is solved by an integral equation method, where the contact stress appears as the unknown function. By a trigonometric expansion, the problem is reduced to a number of uncoupled two-dim...... of the vibration frequency of various plate stiffnesses and the normal component of the surface displacement field for simple excitation of the plate and passage of a plane Rayleigh wave.......The asymmetric problem of a vibrating circular elastic plate in frictionless contact with an elastic half space is solved by an integral equation method, where the contact stress appears as the unknown function. By a trigonometric expansion, the problem is reduced to a number of uncoupled two......-dimensional problems. The radial variations of contact stresses and surface displacements are represented by polynomials, the coefficients of which are directly related by an infinite matrix that is a function of the vibration frequency. The results include a parametric study of the power input as a function...
Response of a circular steel plate with different weld geometries subject to impact loading
Directory of Open Access Journals (Sweden)
Meyer L.W.
2012-08-01
Full Text Available The dynamic response of clamped circular steel plates was experimentally investigated under impact loading. The experiments were performed using a high energy drop weight machine with a 5 ton drop weight, which falls from a height of 0.8 m and results in a total impact energy of 40 kJ. Target plates of 10 mm thickness and 580 mm diameter were welded in three different geometrical configurations of weld elements on the lower side. The impact process was carried out using a hemispherical punch. The force was registered by strain gages on the punch. A full dynamic strain field measurement was applied on the tension side using two high speed cameras. The evaluation of the strain field was carried out with the speckle photography technique. The effect of cracks and welding on the deformation and failure behavior was studied using pre-cracked disks and plates with welded webs, welded circular discs and also with a weld seam only. The failure of the plates was registered using the high speed cameras and from the force signal. The results are analyzed and discussed regarding the behavior of the material and component under high rate loading.
Propelling plastics into the circular economy - weeding out the toxics first.
Leslie, H A; Leonards, P E G; Brandsma, S H; de Boer, J; Jonkers, N
2016-09-01
The Stockholm Convention bans toxic chemicals on its persistent organic pollutants (POPs) list in order to promote cleaner production and prevent POPs accumulation in the global environment. The original 'dirty dozen' set of POPs has been expanded to include some of the brominated diphenyl ether flame retardants (POP-BDEs). In addition to cleaner production, there is an urgent need for increased resource efficiency to address the finite amount of raw materials on Earth. Recycling plastic enhances resource efficiency and is part of the circular economy approach, but how clean are the materials we are recycling? With the help of a new screening method and detailed analyses, we set out to investigate where these largely obsolete BDEs were showing up in Dutch automotive and electronics waste streams, calculate mass flows and determine to what extent they are entering the new product chains. Our study revealed that banned BDEs and other toxic flame retardants are found at high concentrations in certain plastic materials destined for recycling markets. They were also found in a variety of new consumer products, including children's toys. A mass flow analysis showed that 22% of all the POP-BDE in waste electrical and electronic equipment (WEEE) is expected to end up in recycled plastics because these toxic, bioaccumulative and persistent substances are currently not effectively separated out of plastic waste streams. In the automotive sector, this is 14%, while an additional 19% is expected to end up in second-hand parts (reuse). These results raise the issue of delicate trade-offs between consumer safety/cleaner production and resource efficiency. As petroleum intensive materials, plastic products ought to be repaired, reused, remanufactured and recycled, making good use of the 'inner circles' of the circular economy. Keeping hazardous substances - whether they are well known POPs or emerging contaminants - out of products and plastic waste streams could make these
Modeling Open-Loop MEMS Tunneling Accelerometer Based on Circular Plate
Directory of Open Access Journals (Sweden)
Hossein Jodat Kordlar
2007-04-01
Full Text Available In this paper open-loop MEMS tunneling accelerometer was modeled based on a clamped micro circular plate with a tip tunneling at its centre. Mechanical behavior of the micro plate was studied deriving governing equation based on classic Kirchhoff thin plate theory and it was discretized using Galerkin method. Dynamic response of the proposed accelerometer due to step and harmonic external excitation was studied and the magnitude of the applied acceleration was identified by measuring of the changing of tunneling current. Obtained results show that the proposed tunneling accelerometer very sensitive and it can be measure acceleration with very high resolution but very small gap of tip tunneling limit the range of measurable acceleration.
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Ante Skoblar
2016-03-01
Full Text Available It is suitable to reduce thickness of circular saw when trying to enhance usability of wood raw material, but reducing thickness also causes reduction of permissible rotational speed which reduces sawing speed. If one increase circular saw rotational speed over permissible one the quality of machined surfaces will reduce because of enhanced vibrations. Permissible rotational speed can be calculated from critical rotational speed which can be defined from natural frequencies of the saw. In this article critical rotational speeds of standard clamped saws (with flat disk surface and without slots are calculated by using finite element method and classical theory of thin plates on annular plates. Mode shapes and natural frequencies of annular plates are determined by using Bessel functions and by using polynomial functions. Obtained results suggest that standard clamped circular saws without slots and with relatively small teeth can be determined from classical theory of thin plates for annular plates with accuracy depending on clamping ratio.
Institute of Scientific and Technical Information of China (English)
WANG Zhongmin; GAO Jingbo; LI Huixia; LIU Hongzhao
2008-01-01
The non-linear dynamic behaviors of thermoelastic circular plate with varying thickness subjected to radially uniformly distributed follower forces are considered. Two coupled non-linear differential equations of motion for this problem are derived in terms of the transverse deflection and radial displacement component of the mid-plane of the plate. Using the Kantorovich averaging method, the differential equation of mode shape of the plate is derived, and the eigenvalue problem is solved by using shooting method. The eigencurves for frequencies and critical loads of the circular plate with unmovable simply supported edge and clamped edge are obtained. The effects of the variation of thickness and temperature on the frequencies and critical loads of the thermoelastic circular plate subjected to radially uniformly distributed follower forces are then discussed.
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Şandru Mirela
2016-09-01
Full Text Available This paper presents an analytical study which deals with the behavior of the circular plates in bending theory, considering the soil-structure interaction under Winkler's hypothesis. It was intended to illustrate the variation of internal forces and deformations according to the flexibility coefficient of plates considering three models: a fixed solid circular plate subjected to a uniformly distributed load, a fixed solid circular plate acted by a displacement applied on the exterior contour and a solid plate subjected to a temperature gradient. For this study the computation relations were written as a product between a dimensional and a non-dimensional factor, the last one indicating the variation of internal forces and deformations. For each type of action there are presented results obtained using the finite element method to illustrate the differences between this method and the analytical computation.
ANALYSIS OF RESIDUAL STRESS IN THE METAL MATRIX COMPOSITE PLATES WITH CIRCULAR HOLES
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Muzaffer TOPCU
1999-02-01
Full Text Available In this study, elasto-plastic stress analysis have been made for metal matrix composite plates containing a central hole subjected to uniaxial tension under various uniformly distributed loads. In the solution, ısoparametric rectangular elements with nine nodes have been used. In the reinforcement angles 0 and 90 degrees for different diameters of the holes ın the vicinity of the holes residual stress variations have been investigated.
Flow past a circular cylinder with a permeable wake splitter plate
Cardell, Gregory S.
1993-08-01
Measurements in the near wake region of a circular cylinder in a uniform flow in the Reynolds number range 2.5 x 10(exp 3) is approximately less than Re is approximately less than 1.8 x 10(exp 4) with permeable splitter plates spanning the wake center plane are presented. Permeability is defined by the pressure drop across the plates, and the relationship between permeability and plate solidity is determined for a set of plates constructed from woven wire mesh permitting unambiguous characterization of the splitter plates by the solidity. The effects of different solidities on the flow in the near wake are investigated using smoke wire flow visualization, hot-wire anemometry, and measurements of the mean pressure at the cylinder surface, and the results are related to cylinder flow without a splitter plate. Flow visualization results demonstrate that the introduction of low solidity splitter plates does not change the basic near wake structure, and that sufficiently high solidity uncouples the large-scale wake instability from the body, with the primary vortex formation occurring downstream of the separation bubble due to instability of the wake profile. Hot-wire and surface pressure measurements confirm and quantify the flow visualization results, showing that the permeable splitter plates reduce the drag and modify the primary wake frequency. When the solidity is high enough that the wake is convectively unstable, the base pressure is independent of the Reynolds number and solidity. For a wide range of solidities, the same asymptotic value of the Strouhal number is reached at high Reynolds numbers. The relationship between the Strouhal number and the base pressure is discussed.
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
An analysis of buckling/snapping and bending behaviors of magneto-elastic-plastic interaction and coupling for cantilever rectangular soft ferromagnetic plates is presented. Based on the expression of magnetic force from the variational principle of ferromagnetic plates, the buckling and bending theory of thin plates, the Mises yield criterion and the increment theory for plastic deformation, we establish a numerical code to quantitatively simulate the behaviors of the nonlinearly multi-fields coupling problems by the finite element method. Along with the phenomena of buckling/snapping and bending, or the characteristic curve of deflection versus magnitude of applied magnetic fields being numerically displayed, the critical loads of buckling/snapping,and the influences of plastic deformation and the width of plate on these critical loads, the plastic regions expanding with the magnitude of applied magnetic field, as well as the evolvement of deflection configuration of the plate are numerically obtained in a case study.
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Staňák P.
2013-06-01
Full Text Available Proposed paper presents application of the patch test for meshless analysis of piezoelectric circular plate with functionally graded material properties. Functionally graded materials (FGM are the special class of composite materials with continuous variation of volume fraction of constituents in predominant direction. Patch test analysis is an important tool in numerical methods for addressing the convergence. Meshless local Petrov-Galerkin (MLPG method together with moving least-squares (MLS approximation scheme is applied in the analysis. No finite elements are required for approximation or integration of unknown quantities. Circular plate is considered as a 3-D axisymmetric piezoelectric solid. Considering the axial symmetry, the problem is reduced to a 2-dimensinal one. Displacement and electric potential fields are prescribed on the outer boundaries in order to reach the state of constant stress field inside the considered plate as required by the patch test and the governing equations. Values of prescribed mechanical and electrical fields must be determined in order to comply with applied FGM gradation rule. Convergence study is performed to assess the considered meshless approach and several conclusions are finally presented.
Thermal stresses induced by a point heat source in a circular plate by quasi-static approach
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The present paper deals with the determination of quasi-static thermal stresses due to an instantaneous point heat source of strength g_(pi) situated at certain circle along the radial direction of the circular plate and releasing its heat spontaneously at time t=τ.A circular plate is considered having arbitrary initial temperature and subjected to time dependent heat flux at the fixed circular boundary of r=b.The governing heat conduction equation is solved by using the integral transform method,and res...
Effects of Velocity-Slip and Viscosity Variation in Squeeze Film Lubrication of Two Circular Plates
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R.R. Rao
2013-03-01
Full Text Available A generalized form of Reynolds equation for two symmetrical surfaces is taken by considering velocity-slip at the bearing surfaces. This equation is applied to study the effects of velocity-slip and viscosity variation for the lubrication of squeeze films between two circular plates. Expressions for the load capacity and squeezing time obtained are also studied theoretically for various parameters. The load capacity and squeezing time decreases due to slip. They increase due to the presence of high viscous layer near the surface and decrease due to low viscous layer.
Alternate model of Chladni figures for the circular homogenous thin plate case with open boundaries
Trejo-Mandujano, H. A.; Mijares-Bernal, G.; Ordoñez-Casanova, E. G.
2015-01-01
The wave equation is a direct but a complex approach to solve analytically for the Chladni figures, mainly because of the complications that non-smooth and open boundary conditions impose. In this paper, we present an alternate solution model based on the principle of Huygens-Fresnel and on the ideas of Bohr for the hydrogen atom. The proposed model has been implemented numerically and compared, with good agreement, to our own experimental results for the case of a thin homogenous circular plate with open boundaries.
Institute of Scientific and Technical Information of China (English)
ZhouYouhe; GaoYuanwen; ZhengXiaojing
2004-01-01
The magneto-plastic instability of a ferromagnetic beam-type plate with simple supports and small initial imperfection is analytically investigated in this paper for that the plastic deformation of the plate with a linear-strain hardening relation is considered when the plate is located in a strong uniformly distributed magnetic field. After the distribution of magnetic fields related to the deflected configuration of plate is imaginably divided into two parts, i.e.,one is related to the flat plate and the other dependent on the perturbation of magnetic fields for which the plate configuration changes from the flat into the deformed state, the perturbation technique is employed to analyze the distribution of the perturbation magnetic fields in and out-of the magnetic medium of the ferromagnetic structure in a transverse magnetic field, which leads to some analytical formulae/solutions for the magnetic fields and the resulting magnetic force exerted on the plate. Based on them, the magneto-plastic buckling and snapping of the plate in a transverse magnetic field is discussed, and the critical magnetic field is analytically formulated in terms of the parameters of geometry and material of the plate employed by solving the governing equation of the magneto-plastic plate in the applied magnetic field. Further, the sensitivity of the initial imperfection on the magneto-plastic instability, expressed by an amplification function, is obtained by solving the dynamic equation of deflection of the plate after the inertial force in the transverse direction is taken into account. The results obtained show that the critical magnetic field is sensitive to the plastic characteristic, e.g., hardening coefficient, and the instability mode and deflection of the plate are dependent on the geometrical imperfection as well.
Energy Technology Data Exchange (ETDEWEB)
Anjomshoa, Amin; Tahani, Masoud [Ferdowsi University, Mashhad (Iran, Islamic Republic of)
2016-06-15
In the present study a continuum model based on the nonlocal elasticity theory is developed for free vibration analysis of embedded ortho tropic thick circular and elliptical nano-plates rested on an elastic foundation. The elastic foundation is considered to behave like a Pasternak type of foundations. Governing equations for vibrating nano-plate are derived according to the Mindlin plate theory in which the effects of shear deformations of nano-plate are also included. The Galerkin method is then employed to obtain the size dependent natural frequencies of nano-plate. The solution procedure considers the entire nano-plate as a single super-continuum element. Effect of nonlocal parameter, lengths of nano-plate, aspect ratio, mode number, material properties, thickness and foundation on circular frequencies are investigated. It is seen that the nonlocal frequencies of the nano-plate are smaller in comparison to those from the classical theory and this is more pronounced for small lengths and higher vibration modes. It is also found that as the aspect ratio increases or the nanoplate becomes more elliptical, the small scale effect on natural frequencies increases. Further, it is observed that the elastic foundation decreases the influence of nonlocal parameter on the results. Since the effect of shear deformations plays an important role in vibration analysis and design of nano-plates, by predicting smaller values for fundamental frequencies, the study of these nano-structures using thick plate theories such as Mindlin plate theory is essential.
Lu, Lin; Guo, Xiao-ling; Tang, Guo-qiang; Liu, Ming-ming; Chen, Chuan-qi; Xie, Zhi-hua
2016-09-01
Numerical results of fluid flow over a rotationally oscillating circular cylinder with splitter plate are presented here. Different from the previous examinations with freely rotatable assembly, the fluid and structure interactions are treated as a coupled dynamic system by fully considering the structural inertia, stiffness, and damping. The hydrodynamic characteristics are examined in terms of reduced velocity Ur at a relatively low Reynolds number Re = 100 for different plate lengths of L/D = 0.5, 1.0, and 1.5, where Ur = U/(Dfn), Re = UD/υ and fn = (κ/J)0.5/2π with U the free stream velocity, D the diameter of the circular cylinder, υ the fluid kinematic viscosity, fn the natural frequency, J the inertial moment, κ the torsional stiffness, and L the plate length. Contrast to the freely rotating cylinder/plate body, that is, in the limit of κ → 0 or Ur →∞, remarkable rotary oscillation is observed at relatively low reduced velocities. For the typical case with L/D = 1.0, the maximum amplitude may reach five times that at the highest reduced velocity of Ur = 15.0 considered in this work. At the critical reduced velocity Ur = 4.2, notable hydrodynamic jumps are identified for the rotation amplitude, response frequency, mean drag coefficient, lift amplitude, and vortex shedding frequency. Moreover, the phase angle between the fluid moment and rotary oscillation abruptly changes from 0 to π at Ur = 6.5. Due to the combined effect of fluid moment, rotation response, and phase difference, the natural frequency of the rotating body varies in flow, leading to a wide regime of lock-in/synchronization (Ur ≥4.2, for L/D = 1.0). The phenomenon of rotation bifurcation, i.e., the equilibrium position of the rotary oscillation deflects to a position which is not parallel to the free stream, is found to only occur at higher reduced velocities. The longer splitter plate has the lower critical reduced velocity. The occurrence of bifurcation is attributed to the
Institute of Scientific and Technical Information of China (English)
2008-01-01
Based on the first order shear deformation theory and classic buckling theory, the paper investigates the creep buckling behavior of viscoelastic laminated plates and laminated circular cylindrical shells. The analysis and elaboration of both instantaneous elastic critic load and durable critic load are emphasized. The buckling load in phase domain is obtained from governing equations by applying Laplace transform, and the instantaneous elastic critic load and durable critic load are determined according to the extreme value theorem for inverse Laplace transform. It is shown that viscoelastic approach and quasi-elastic approach yield identical solutions for these two types of critic load respectively. A transverse disturbance model is developed to give the same mechanics significance of durable critic load as that of elastic critic load. Two types of critic loads of boron/epoxy composite laminated plates and circular cylindrical shells are discussed in detail individually, and the influencing factors to induce creep buckling are revealed by examining the viscoelasticity incorporated in transverse shear deformation and in-plane flexibility.
Linearized plastic plate models as Gamma-limits of 3D finite elastoplasticity
Davoli, Elisa
2013-01-01
The subject of this paper is the rigorous derivation of reduced models for a thin plate by means of {\\Gamma}-convergence, in the framework of finite plasticity. Denoting by {\\epsilon} the thickness of the plate, we analyse the case where the scaling factor of the elasto-plastic energy is of order {\\epsilon}^(2{\\alpha}-2), with {\\alpha}>=3. According to the value of {\\alpha}, partially or fully linearized models are deduced, which correspond, in the absence of plastic deformation, to the Von K...
TORSIONAL VIBRATIONS OF RIGID CIRCULAR PLATE ON TRANSVERSELY ISOTROPIC SATURATED SOIL
Institute of Scientific and Technical Information of China (English)
WU Da-zhi; CAI Yuan-qiang; XU Chang-jie; ZHAN Hong
2006-01-01
An analytical method was presented for the torsional vibrations of a rigid disk resting on transversely isotropic saturated soil. By Hankel transform, the dynamic governing differential equations for transversely isotropic saturated poroelastic medium were solved. Considering the mixed boundary-value conditions, the dual integral equations of torsional vibrations of a rigid circular plate resting on transversely isotropic saturated soil were established. By appropriate transform, the dual integral equations were converted into a Fredholm integral equation of the second kind. Subsequently, the dynamic compliance coefficient, the torsional angular amplitude of the foundation and the contact shear stress were expressed explicitly. Selected examples were presented to analyse the influence of saturated soil's anisotropy on the foundation's vibrations.
ADHESIVE CONTACT PROBLEM OF AXISYMMETRIC MINIATURE CIRCULAR PLATES WITH CENTRAL RIGID BUMP
Institute of Scientific and Technical Information of China (English)
Fu Yiming; Li Sheng; Tian Yanping
2006-01-01
Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform transverse pressure and in-plane tensile force in the radial direction was analyzed. And an analytical solution is presented by using the perturbation method. The relation of surface adhesive energies with critical load to detach the contacted surfaces is obtained. In the numerical results, the effects of adhesive energy, in-plane tensile force, rigid bump size and contact radius on the critical load are discussed, and the relation of critical contact radius with the gap between the central rigid bump and the substrate for different adhesive energies is investigated.
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Mohammad Mehdi Rashidi
2010-01-01
Full Text Available We investigated an axisymmetric unsteady two-dimensional flow of nonconducting, incompressible second grade fluid between two circular plates. The similarity transformation is applied to reduce governing partial differential equation (PDE to a nonlinear ordinary differential equation (ODE in dimensionless form. The resulting nonlinear boundary value problem is solved using homotopy analysis method and numerical method. The effects of appropriate dimensionless parameters on the velocity profiles are studied. The total resistance to the upper plate has been calculated.
Energy Technology Data Exchange (ETDEWEB)
Rastgoo, A. [University of Tehran, Tehran (Iran, Islamic Republic of); Ebrahimi, F. [lmam Khomeini International University, Qazvin (Iran, Islamic Republic of); Kargarnovin, M. H. [Sharif University of Technology, Tehran (Iran, Islamic Republic of)
2008-06-15
In this paper, a free vibration analysis of moderately thick circular functionally graded (FG) plate integrated with two thin piezoelectric (PZT4) layers is presented based on Mindlin plate theory. The material properties of the FG core plate are assumed to be graded in the thickness direction, while the distribution of electric potential field along the thickness of piezoelectric layers is simulated by sinusoidal function. The differential equations of motion are solved analytically for two boundary conditions of the plate: clamped edge and simply supported edge. The analytical solution is validated by comparing the obtained resonant frequencies with those of an isotropic host plate. The emphasis is placed on investigating the effect of varying the gradient index of FG plate on the free vibration characteristics of the structure. Good agreement between the results of this paper and those of the finite element analyses validated the presented approach
TORSIONAL VIBRATIONS OF A RIGID CIRCULAR PLATE ON SATURATED STRATUM OVERLAYING BEDROCK
Institute of Scientific and Technical Information of China (English)
CaiYuanqiang; WuDazhi; XuChangjie
2005-01-01
The torsional vibration of a rigid plate resting on saturated stratum overlaying bedrock has been analysed for the first time. The dynamic governing differential equations for saturated poroelastic medium are solved by employing the technology of Hankel transform. By taking into account the boundary conditions, the dual integral equations of torsional vibration of a rigid circular plate are established, which are further converted into a Fredholm integral equation of the second kind. Subsequently, the dynamic compliance coefficients of the foundation on saturated stratum, the contact shear stress under the foundation and the angular amplitude of the foundation are evaluated. Numerical results indicate that, when the dimensionless height is bigger than 5, saturated stratum overlaying bedrock can be treated as saturated half space approximately. When the dimensionless frequency is low, the permeability of the soil must be taken into account. Furthermore, when the vibration frequency is a constant, the height of the saturated stratum has a slight effect on the dimensionless contact shear stress under the foundation.
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
The non-axisymmetrical vibration of elastic circular plate resting on a layered transversely isotropic saturated ground was studied. First, the 3-d dynamic equations in cylindrical coordinate for transversely isotropic saturated soils were transformed into a group of governing differential equations with 1-order by the technique of Fourier expanding with respect to azimuth, and the state equation is established by Hankel integral transform method, furthermore the transfer matrixes within layered media are derived based on the solutions of the state equation. Secondly, by the transfer matrixes, the general solutions of dynamic response for layered transversely isotropic saturated ground excited by an arbitrary harmonic force were established under the boundary conditions,drainage conditions on the surface of ground as well as the contact conditions. Thirdly, the problem was led to a pair of dual integral equations describing the mixed boundaryvalue problem which can be reduced to the Fredholm integral equations of the second kind solved by numerical procedure easily. At the end of this paper, a numerical result concerning vertical and radical displacements both the surface of saturated ground and plate is evaluated.
Institute of Scientific and Technical Information of China (English)
段浩; 胡宗武; 杨赪石; 黎佑铭
2003-01-01
The rubber circular plate is considered as a kind of membrane. Based on the character that there existsno bending-moment inside a membrane, the geometric behavior of the rubber circular plate in expanding state wasdescribed with the aid of a group of mathematic method. The relationship between deflection and load was attainedby means of calculating stress and strain inside the curved-surface of rubber plate. Meantime, based on Henckymethod, the relationship between deflection and load was attained and considered as the Hencky solution. The dif-ferent results given rise by the two different resolving methods were compared. The deviation results from theHencky method was discussed, and a kind of correcting method was put forward.
Elasto-plastic buckling analysis of laminated plates including interfacial damage
Energy Technology Data Exchange (ETDEWEB)
Tian, Yanping; Fu, Yiming [Hunan University, State Key Laboratory of Advanced Technology of Design and Manufacturing for Vehicle Body, College of Mechanics and Aerospace, Changsha (China)
2010-06-15
Elasto-plastic buckling of orthotropic laminated plates, which include interfacial damage, is analyzed in detail. Firstly, a novel mixed hardening yield criterion, as an improvement of Hill's counterpart, is proposed for the orthotropic materials on the basis of the plastic theory. And differing from Hill's theory, the present yield criterion is related to the spherical tensor of stress. Then, the incremental elasto-plastic constitutive relations of the mixed hardening orthotropic materials are presented. Secondly, the incremental static equilibrium equations for laminated plates including interfacial damage are established based on Von-Karman type theory and the principle of minimum potential energy. Finally, the elasto-plastic buckling of laminated plates are solved by adopting the Galerkin method and iteration scheme. The numerical results show that buckling of the plate occurs easier due to the existence of interfacial damage, and the critical load trends to constant when the interfacial damage approaches a certain degree. Also, the effect of anisotropy on buckling is obvious and the analysis of elasto-plastic buckling is necessary. (orig.)
Plasticity, Fracture and Friction in Steady-State Plate Cutting
DEFF Research Database (Denmark)
Simonsen, Bo Cerup; Wierzbicki, Tomasz
1997-01-01
A closed form solution to the problem of steady-state wedge cutting through a ductile metal plate is presented. The considered problem is an idealization of a ship bottom raking process, i.e. a continuous cutting damage of a ship bottom by a hard knife-like rock in a grounding event. A new...
Direct writing patterns for electroless plated copper thin film on plastic substrates.
Liao, Ying-Chih; Kao, Zhen-Kai
2012-10-24
A simple and efficient method is developed to create conductive copper thin films on polymer surfaces. Instead of regular palladium colloid inks, micropatterns of silver nitrate inks, which serve as an activating agent for copper plating, were printed and dried on flexible plastic substrates. The printed plastic sheets were then immersed in an electroless copper plating bath at 55 °C for 2 min to create copper thin films on the printed patterns. The prepared copper films have an electrical conductivity as high as 83% of bulk copper and show good adhesion on PET or PI substrates.
Monfared, Vahid
2016-06-01
Analytically based model is presented for behavioral analysis of the plastic deformations in the reinforced materials using the circular (trigonometric) functions. The analytical method is proposed to predict creep behavior of the fibrous composites based on basic and constitutive equations under a tensile axial stress. New insight of the work is to predict some important behaviors of the creeping matrix. In the present model, the prediction of the behaviors is simpler than the available methods. Principal creep strain rate behaviors are very noteworthy for designing the fibrous composites in the creeping composites. Analysis of the mentioned parameter behavior in the reinforced materials is necessary to analyze failure, fracture, and fatigue studies in the creep of the short fiber composites. Shuttles, spaceships, turbine blades and discs, and nozzle guide vanes are commonly subjected to the creep effects. Also, predicting the creep behavior is significant to design the optoelectronic and photonic advanced composites with optical fibers. As a result, the uniform behavior with constant gradient is seen in the principal creep strain rate behavior, and also creep rupture may happen at the fiber end. Finally, good agreements are found through comparing the obtained analytical and FEM results.
Monfared, Vahid
2016-12-01
Analytically based model is presented for behavioral analysis of the plastic deformations in the reinforced materials using the circular (trigonometric) functions. The analytical method is proposed to predict creep behavior of the fibrous composites based on basic and constitutive equations under a tensile axial stress. New insight of the work is to predict some important behaviors of the creeping matrix. In the present model, the prediction of the behaviors is simpler than the available methods. Principal creep strain rate behaviors are very noteworthy for designing the fibrous composites in the creeping composites. Analysis of the mentioned parameter behavior in the reinforced materials is necessary to analyze failure, fracture, and fatigue studies in the creep of the short fiber composites. Shuttles, spaceships, turbine blades and discs, and nozzle guide vanes are commonly subjected to the creep effects. Also, predicting the creep behavior is significant to design the optoelectronic and photonic advanced composites with optical fibers. As a result, the uniform behavior with constant gradient is seen in the principal creep strain rate behavior, and also creep rupture may happen at the fiber end. Finally, good agreements are found through comparing the obtained analytical and FEM results.
Electroless Plating on Plastic Induced by Selective Laser Activation
DEFF Research Database (Denmark)
Zhang, Yang; Tang, Peter Torben; Hansen, Hans Nørgaard
2009-01-01
This paper presents a new method for selective micro metallization of polymers. A Nd:YAG laser is employed to draw patterns on polymer surfaces that are submerged in a liquid (usually water). After subsequent activation with palladium chloride and followed by auto-catalytic electroless plating...... in width with 50μm between two tracks, but further optimization is expected in this field. Due to the porous and rough structure of the laser track, excellent adhesion between metallization and substrate is obtained. On top of the first copper layer, additional metal such as nickel, gold, palladium or tin...
Laura, P. A. A.; Masiá, U.; Avalos, D. R.
2006-05-01
Rayleigh-Ritz variational method is applied to the determination of the first four frequency coefficients for the title problem by making use of coordinate functions which identically satisfy the boundary conditions at the outer edge. Good stability and convergence properties are found. The mathematical model seems to be realistic and accurate, within the realm of the classical theory of vibrating plates.
Effect of plastic deformation on diffusion-rolling bonding of steel sandwich plates
Institute of Scientific and Technical Information of China (English)
Hong Li; Jingtao Han
2006-01-01
Diffusion bonding is one of the most important techniques for composite materials, while bonding temperature, holding time,and rolling reduction are the key parameters that affect the bonding strength of sandwich plates. To study the effect of plastic deformation on the bonding strength, laboratory experiments were carried on a Gleeble Thermal Simulator to imitate the diffusion-rolling bonding under different reductions for steel sandwich plates. The bonding strength and interlayer film thickness were measured, and the element diffusion was analyzed using line scanning. The relationship between the bonding strength and "diffused interlayer" thickness was investigated. It has been found that the bonding strength increases with reduction, whereas the interlayer film thickness decreases gradually as the reduction increases. The diffusion under plastic deformation is obviously enhanced in comparison with that of nil reduction. The mechanism of plastic deformation effect on the diffusion bonding and related models have been discussed.
Directory of Open Access Journals (Sweden)
Rachmadi Gewa Saputra
2014-03-01
Full Text Available Harga minyak dunia cenderung mengalami peningkatan dalam beberapa tahun terakhir sehingga manusia berfikir untuk memanfaatkan setiap penggunaan minyak bumi. Dengan berkembangnya teknologi saat ini waste energy yang berupa gas hasil pembakaran pada engine dapat dimanfaatkan menjadi bentuk energi lain menggunakan heat recovery system. Pada tugas akhir ini dilakukan desain sebuah heat exchanger tipe circular tubes continuous plate fin dengan susunan tube aligned yang digunakan untuk menyerap waste energy yang berupa exhaust gas. Untuk mendapatkan dimensi desain yang sesuai digunakan metode ΔTLMTD. Metode ini digunakan untuk menentukan nilai dari overall heat transfer desain dari heat exchanger, kemudian dilakukan perhitungan untuk nilai overall heat transfer hitung. Setelah didapatkan nilai dari overall heat transfer secara desain dan hitung maka dilakukan iterasi untuk mendapatkan dimensi heat exchanger yang memiliki nilai error paling kecil antara nilai overall heat transfer desain dan hitung. Untuk pengujian performa dari heat exchanger yang telah didesain maka dilakukan variasi kacepatan exhaust gas yang melewati heat exchanger, yaitu 0.4 m/s, 0.3 m/s, dan 0.2 m/s. Exhaust gas yang digunakan memiliki temperatur 280oC. Pada tugas akhir ini didapatkan desain compact heat exchanger dengan dimensi panjang 0.38 m, lebar 0.45 m, dan tebal 0.04m. Setelah dilakukan pengujian dengan memvariasikan kecepatan dari exhaust gas yang melewati heat exchanger maka didapatkan bahwa nilai dari qaktual dari heat exchanger mengalami kenaikan dengan bertambahnya reynolds number akibat bertambahnya kecepatan exhaust gas, kemudian nilai dari effectiveness akan mengalami penurunan untuk setiap kenaikan dari reynold number exhaust gas. Selain itu nilai dari NTU heat exchanger juga mengalami penurunan dengan bertambahnya reynold number exhaust gas. Untuk nilai overall heat transfer dari heat exchanger yang didesain akan mengalami kenaikan akibat bertambahnya nilai
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
The permanent deflection of a thin circular plate struck normally at its center by a projectile is studied by an approximate theoretical analysis, FEM simulation and experiment. The plate made of rate sensitive and strain-hardening material undergoes serious local deformation but is not perforated during the impact. The theoretical analysis is based on an energy approach,in which the Cowper-Symonds equation is used for the consideration of strain rate sensitive effects and the parameters involved are determined with the aid of experimental data. The maximum permanent deflections predicted by the theoretical model are compared with those of FEM simulation and published papers obtained both by theory and experiment, and good agreement is achieved for a wide range of thickness of the plates and initial impact velocities.
Liu, Jiamin; Liang, Huawei; Zhang, Min; Su, Hong
2014-09-10
We report on the broadband terahertz (THz) transmission within a symmetrical plastic film coated parallel-plate waveguide. We theoretically study the antiresonant reflecting mechanism of the waveguide, and we find that the broadband THz wave can transmit in this waveguide with ultralow loss. The loss of the TM mode in this waveguide can be 4 orders of magnitude lower than the uncoated parallel-plate waveguide. The transmission bandwidth of this waveguide is up to 5.12 THz. We further show the mode field distributions which explain the loss mechanism.
Kononets, I
2002-01-01
%NA59 %title\\\\ \\\\We present a proposal to study the use of a crystal as a `quarter-wave plate' to produce high energy circularly polarized photons, starting from unpolarized electrons. The intention is to generate linearly polarized photons by letting electrons pass a crystalline target, where they interact coherently with the lattice nuclei. The photon polarization is subsequently turned into circular polarization after passing another crystal, which acts as a `quarter-wave plate'.
Vibration of an Elastic Circular Plate on an Elastic Half Space
DEFF Research Database (Denmark)
Krenk, Steen; Schmidt, H.
1981-01-01
The axisymmetric problem of a vibrating elastic plate on an elastic half space is solved by a direct method, in which the contact stresses and the normal displacements of the plate are taken as the unknown functions. First, the influence functions that give the displacements in terms...... influence from the elastic properties of the plate....
Functional Rehabilitation With a Foot Plate Modification for Circular External Fixation
2013-04-05
neurologic injury,3,5,6,16,19 multiple studies3,5 have suggested that weight bearing in an ankle-spanning circular external fix- ator must be delayed until...the patient has radiographic evi- dence of healing. In the past, many limb salvage patients at our institution witnessed their amputee counterparts...Only 1 patient was able to truly run in his circular exter- nal fixator. There were multiple complications documented that hin- dered the rehabilitation
Dynamic and buckling analysis of a thin elastic-plastic square plate in a uniform temperature field
Institute of Scientific and Technical Information of China (English)
Shifu Xiao; Bin Chen
2005-01-01
The nonlinear models of the elastic and elasticlinear strain-hardening square plates with four immovably simply-supported edges are established by employing Hamilton's Variational Principle in a uniform temperature field. The unilateral equilibrium equations satisfied by the plastically buckled equilibria are also established. Dynamics and stability of the elastic and plastic plates are investigated analytically and the buckled equilibria are investigated by employing Galerkin-Ritz's method. The vibration frequencies, the first critical temperature differences of instability or buckling, the elastically buckled equilibria and the extremes depending on the final loading temperature difference of the plastically buckled equillibria of the plate are obtained. The results indicate that the critical buckling value of the plastic plate is lower than its critical instability value and the critical value of its buckled equilibria turning back to the trivial equilibrium are higher than the value. However, three critical values of the elastic plate are equal. The unidirectional snap-through may occur both at the stress-strain boundary of elasticity and plasticity and at the initial stage of unloading of the plastic plate.
Asemi, K.; Ashrafi, H.; Shariyat, M.
2016-07-01
Static and free vibration analyses of plates with circular holes are performed based on the three-dimensional theory of elasticity. The plates are made of a functionally graded material (FGM), and the volume fractions of the constituent materials vary continuously across the plate. The effective properties of the FGM plate are estimated by using the Mori-Tanaka homogenization method. A graded finite element method based on the Rayleigh-Ritz energy formulation is used to solve the problem. Effects of different volume fractions of the materials and hole sizes on the behavior of FGM plates under uniaxial tension are investigated. Natural frequencies of a fully clamped FGM plate with a circular cutout are derived. The results obtained are compared with available experimental data.
Simulation of the Collapse of an Underwater Explosion Bubble under a Circular Plate
Kit-Keung Kan; Stuhmiller, James H.; Chan, Philemon C.
2005-01-01
A two-fluid, computational fluid dynamics study of the phenomena of bubble collapse under a submersed flat plate has been performed. In order to handle the rapidly changing bubble-water interface accurately, second order upwind differencing is used in calculating the advection term. Good agreement with experimental data is obtained for the pressure distribution on the plate. The computational results provide insight into the phenomenology of the jet impact, the formation of a radial hydraulic...
Azhar KAMARUDIN, Kamarul; HAMID, Iskandar ABDUL
2017-01-01
This work describes an experimental investigation of the pretensioned thin plates made of Carbon Fibre Reinforced Plastic (CFRP) struck by hemispherical and blunt projectiles at various impact velocities. The experiments were done using a gas gun with combination of pretension equipment positioned at the end of gun barrel near the nozzle. Measurements of the initial and residual velocities were taken, and the ballistic limit velocity were calculated for each procedures. The pretension target results in reduction of ballistic limit compared to non-pretension target for both flat and hemispherical projectiles. Target impacted by hemispherical projectile experience split at earlier impact velocity compared to target by flat projectile. C-Scan images analysis technique was used to show target impact damaged by hemispherical and flat projectiles. The damage area was shown biggest at ballistic limit velocity and target splitting occurred most for pretention plate.
Thermal elasto-plastic stress analysis during laser heating of a metal plate
Chen, Yanbei; Lu, Jian; Ni, Xiaowu
2008-03-01
During laser heating of a metal material, the continuity of material confines its free expansion, thermal stresses arise. On one hand the thermal expansion of the heated zone of the material increases with the increase of temperature, the thermal stress level increases correspondingly; on the other hand the mechanical properties of the material will change with the increase of temperature, especially the elastic modulus, yield strength and tensile strength drop significantly, which is the so-called thermal softening problem. Due to the effect of the two factors, as the heating time or the intensity of the laser beam increases, it is possible that the stress levels of the heated zone of the material exceed the yield strength, which leads the material to come into a plastic stage. Thus, a thermal plastic problem occurs. In this study, thermal elasto-plastic stresses during laser heating of a metal plate are computed by the finite element method (FEM) based on thermal elasto-plastic constitutive theory. The mechanical behaviors of the metal material during the laser heating are analyzed. By the analysis of the results, it is found that thermal expansion leads to the increase of stress level early during the laser irradiating, and thermal softening causes the decrease of stress levels in the plastic zone and the slow growth and even decrease of stress levels in elastic zone later. The radial stresses are all compressive stresses, and the hoop stresses are compressive stresses within about the laser spot and are tensile stresses at other place. This work may be beneficial to the laser processing of metal materials.
Simulation of the Collapse of an Underwater Explosion Bubble under a Circular Plate
Directory of Open Access Journals (Sweden)
Kit-Keung Kan
2005-01-01
Full Text Available A two-fluid, computational fluid dynamics study of the phenomena of bubble collapse under a submersed flat plate has been performed. In order to handle the rapidly changing bubble-water interface accurately, second order upwind differencing is used in calculating the advection term. Good agreement with experimental data is obtained for the pressure distribution on the plate. The computational results provide insight into the phenomenology of the jet impact, the formation of a radial hydraulic jump, and the complex interaction of that hydraulic jump with the collapsing toroidal bubble.
Analytical Round Robin for Elastic-Plastic Analysis of Surface Cracked Plates, Phase II Results
Allen, P. A.; Wells, D. N.
2017-01-01
The second phase of an analytical round robin for the elastic-plastic analysis of surface cracks in flat plates was conducted under the auspices of ASTM Interlaboratory Study 732. The interlaboratory study (ILS) had 10 participants with a broad range of expertise and experience, and experimental results from a surface crack tension test in 4142 steel plate loaded well into the elastic-plastic regime provided the basis for the study. The participants were asked to evaluate a surface crack tension test according to the version of the surface crack initiation toughness testing standard published at the time of the ILS, E2899-13. Data were provided to each participant that represent the fundamental information that would be provided by a mechanical test laboratory prior to evaluating the test result. Overall, the participant’s test analysis results were in good agreement and constructive feedback was received that has resulted in an improved published version of the standard E2899-15.
Analytical Round Robin for Elastic-Plastic Analysis of Surface Cracked Plates: Phase I Results
Wells, D. N.; Allen, P. A.
2012-01-01
An analytical round robin for the elastic-plastic analysis of surface cracks in flat plates was conducted with 15 participants. Experimental results from a surface crack tension test in 2219-T8 aluminum plate provided the basis for the inter-laboratory study (ILS). The study proceeded in a blind fashion given that the analysis methodology was not specified to the participants, and key experimental results were withheld. This approach allowed the ILS to serve as a current measure of the state of the art for elastic-plastic fracture mechanics analysis. The analytical results and the associated methodologies were collected for comparison, and sources of variability were studied and isolated. The results of the study revealed that the J-integral analysis methodology using the domain integral method is robust, providing reliable J-integral values without being overly sensitive to modeling details. General modeling choices such as analysis code, model size (mesh density), crack tip meshing, or boundary conditions, were not found to be sources of significant variability. For analyses controlled only by far-field boundary conditions, the greatest source of variability in the J-integral assessment is introduced through the constitutive model. This variability can be substantially reduced by using crack mouth opening displacements to anchor the assessment. Conclusions provide recommendations for analysis standardization.
Directory of Open Access Journals (Sweden)
Essaouini Hilal
2017-01-01
Full Text Available The problem of the small oscillations of an ideal liquid contained in a vessel in uniform rotation has been studied by Kopachevskii and Krein in the case of an entirely rigid vessel [3]. We propose here, a generalization of this model by considering the case of a vessel closed by an elastic circular plate. In this context, the linearized equations of motion of the system plateliquid are derived. Functional analysis is used to obtain a variational equation of the small amplitude vibrations of the coupled system around its equilibrium position, and then two operatorial equations in a suitable Hilbert space are presented and analyzed. We show that the spectrum of the system is real and consists of a countable set of eigenvalues and an essential continuous spectrum filling an interval. Finally the existence and uniqueness theorem for the solution of the associated evolution problem is proved by means the semigroups theory.
Energy Technology Data Exchange (ETDEWEB)
Beng, Yeo Kiam; Tzeng, Woo Wen [Universiti Malaysia Sabah, Sabah (Malaysia)
2017-02-15
This study presents the finite element analysis of plastic collapse and energy absorption of polyurethane-filled aluminium circular tubes under quasi-static transverse loading. Increasing focuses were given to impact damage of structures where energy absorbed during impact could be controlled to avoid total structure collapse of energy absorbers and devices designed to dissipate energy. ABAQUS finite element analysis application was utilized for modelling and simulating the polyurethane-filled aluminium tubes, different set of diameterto- thickness ratios and span lengths, subjected to transverse three-point-bending load. Different sets of polyurethane-filled aluminium tubes subjected to the transverse loading were modelled and simulated. The failure modes and mechanisms of filled tubes and its capabilities as energy absorbers to further improve and strengthening of empty tube were also identified. The results showed that plastic deformation response was affected by the geometric constraints and parameters of the specimens. The diameter-to-thickness ratio and span lengths had shown to play crucial role in optimizing the PU-filled tube as energy absorber.
Directory of Open Access Journals (Sweden)
Jimit R. Patel
2014-01-01
Full Text Available This paper aims to discuss the effect of slip velocity and surface roughness on the performance of Jenkins model based magnetic squeeze film in curved rough circular plates. The upper plate’s curvature parameter is governed by an exponential expression while a hyperbolic form describes the curvature of lower plates. The stochastic model of Christensen and Tonder has been adopted to study the effect of transverse surface roughness of the bearing surfaces. Beavers and Joseph’s slip model has been employed here. The associated Reynolds type equation is solved to obtain the pressure distribution culminating in the calculation of load carrying capacity. The computed results show that the Jenkins model modifies the performance of the bearing system as compared to Neuringer-Rosensweig model, but this model provides little support to the negatively skewed roughness for overcoming the adverse effect of standard deviation and slip velocity even if curvature parameters are suitably chosen. This study establishes that for any type of improvement in the performance characteristics the slip parameter is required to be reduced even if variance (−ve occurs and suitable magnetic strength is in force.
Akbarov, Surkay D.; Cafarova, Fazile I.; Yahnioglu, Nazmiye
2017-02-01
The axisymmetric buckling delamination of the piezoelectric circular sandwich plate with piezoelectric face and elastic (metal) core layers around the interface penny-shaped cracks is investigated. The case is considered where short-circuit conditions with respect to the electrical potential on the upper and lower and also lateral surfaces of face layers are satisfied. It is assumed that the edge surfaces of the cracks have an infinitesimal rotationally symmetric initial imperfection and the development of this imperfection with rotationally symmetric compressive forces acting on the lateral surface of the plate is studied by employing the exact geometrically non-linear field equations and relations of electro-elasticity for piezoelectric materials. Solution to the considered nonlinear problem is reduced to solution of the series boundary value problems derived by applying the linearization procedure with respect to small imperfection of the sought values. Numerical results reveal the effect of piezoelectricity as well as geometrical and material parameters on the critical values are determined numerically by employing finite element method (FEM).
Energy Technology Data Exchange (ETDEWEB)
Ranjit, Shrestha; Kim, Won Tae [Kongju National University, Cheonan (Korea, Republic of); Choi, Man Yong [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)
2016-03-15
The increasing use of composite materials in various industries has evidenced the need for development of more effective nondestructive evaluation methodologies in order to reduce rejected parts and to optimize production cost. Infrared thermography is a noncontact, fast and reliable non-destructive evaluation technique that has received vast and growing attention for diagnostic and monitoring in the recent years. This paper describes the quantitative analysis of artificial defects in Glass fiber reinforced plastic plate by using Lockin infrared thermography. The experimental analysis was performed at several excitation frequencies to investigate the sample ranging from 2.946 Hz down to 0.019 Hz and the effects of each excitation frequency on defect detachability. The four point method was used in post processing of every pixel of thermal images using the MATLAB programming language. The relationship between the phase contrast with defects depth and area was examined. Finally, phase contrast method was used to calculate the defects depth considering the thermal diffusivity of the material being inspected and the excitation frequency for which the defect becomes visible. The obtained results demonstrated the effectiveness of Lock-in infrared thermography as a powerful measurement technique for the inspection of Glass fiber reinforced plastic structures.
RANDOM VIBRATION OF A CURRENT CARRYING CIRCULAR PLATE IN MAGNETIC FIELD%载流圆板的磁弹性随机振动
Institute of Scientific and Technical Information of China (English)
王平; 李晓靓; 白象忠
2012-01-01
The magnetic-elastic random vibration problem of a current-carrying circular plate in a magnetic field is studied. Based on the magneto-elastic theory and the random vibration theory of a continue system with distributed parameters, the magneto-elastic random vibration equation of a current carrying circular plate in a magnetic field was derived. The stochastic response analysis of the circular plate in a magnetic field was finished. The auto-correlation function, power spectral density function and the mean function of the random displacement response of the circular plate in a magnetic field were obtained. In a specific example, the power spectral density function of the displacement response of the circular plate with stationary random current was calculated.%分析载流圆板在磁场中的磁弹性随机振动问题.根据薄板、薄壳体的磁弹性运动方程和连续体的随机振动理论,导出在磁场环境中圆板的磁弹性随机振动方程.对磁场中的载流圆板进行随机响应分析,得到圆板位移响应的自相关函数、功率谱密度函数及均值函数等数字特征.通过具体算例,对处于外加磁场中通入平稳随机电流的导电圆板,计算其位移响应的功率谱密度函数.
Institute of Scientific and Technical Information of China (English)
ZHOU Xiao-ping; LING Tong-hua
2006-01-01
The near crack line analysis method was used to investigate a centric crack loaded by two pairs of point shear forces in a finite plate, and the analytical solution was obtained. The solution includes the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near the crack line, the variations of the length of the plastic zone along the crack line with an external load, and the bearing capacity of a finite plate with a centric crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of small scale yielding theory have not been made and no other assumptions are taken.
Laura, P. A. A.; Avalos, D. R.
2008-05-01
The Rayleigh-Ritz variational method is applied to the determination of the first four frequency coefficients for small amplitude, transverse vibrations of circular plates with an eccentric, rectangular perforation that is elastically restrained against rotation and translation on both edges. Coordinate functions are used which identically satisfy the boundary conditions at the outer circular edge, while the restraining boundary conditions at the inner edge of the cutout are dealt with directly through the energetic terms in the functional expressions. The procedure seems to show very good numerical stability and convergence properties. As an added bonus, the method allows for increased flexibility in dealing with boundary conditions at the edge of the cutout.
Directory of Open Access Journals (Sweden)
Shlyakhin Dmitry
2017-01-01
Full Text Available This paper considers axially symmetric goal of thermos–elasticity for a fixed rigid circular multi-layer isotropic plate with non–stationary heat flows on its front faces. The mathematical model is presented in the form of a not self–adjoint system that includes differential motion equations and a linear equation of the thermal-elastic state in a three-dimensional model. A new closed solution in an unconnected setting is built by the method of finite integral transformation. At the same time, a standardization procedure is conducted at each stage of the solution, which allows to implement an appropriate conversion algorithm. The calculated ratios provide an opportunity to perform a qualitative and quantitative analysis of the associated temperature and mechanical fields and also to examine stress–strain behaviour of the multi–layer systems both under the local thermal shock, which is observed, for example, in the interaction with the laser beam and in the case of uneven unsteady surface heating, which is frequent during the operation of protective construction structures.
2015-08-01
Aeronautical Research Laboratory, Defence Science and Technology Organisation , Department of Defence, Australia, January 1988. 5. D Duprat, D Campassens...Containing a Circular Insert in a Fatigue Test Coupon Witold Waldman AUSTRALIA DEFENCE ORGANISATION No. of Copies Task Sponsor OIC-ASI-DGTA...UNCLASSIFIED DEFENCE SCIENCE AND TECHNOLOGY GROUP DOCUMENT CONTROL DATA 1. DLM/CAVEAT (OF DOCUMENT) 2. TITLE Elasto–Plastic 3D Finite Element
The plastic compressibility of 7075-T651 aluminum-alloy plate
Freed, A. D.; Sandor, B. I.
1986-01-01
The change in volume, and therefore the change in mass density, of an aluminum alloy was measured in uniaxial tension using clip-on extensometers. The experimental data do not agree with the assumption of plastic incompressibility found in the classical theories of plasticity. In fact, the elastic and plastic volume changes are of the same order of magnitude. Plastic anisotropy is thought to be the prime cause of this plastic compressibility.
Sivells, James C; Deters, Owen J
1946-01-01
A method is presented for determining the jet-boundary and plan-form corrections necessary for application to test data for a partial-span model with a reflection plane, an end plate, or no end plate in a closed circular wind tunnel. Examples are worked out for a partial-span model with each of the three end conditions in the Langley 19-foot pressure tunnel and the corrections are applied to measured values of lift, drag, pitching-moment, rolling-moment, and yawing-moment coefficients.
Elasto-plasticity and pore-pressure coupled analysis on the pullout behaviors of a plate anchor
Directory of Open Access Journals (Sweden)
Cun Hu
2015-03-01
Full Text Available A numerical method is proposed for the elasto-plasticity and pore-pressure coupled analysis on the pullout behaviors of a plate anchor. The bounding-surface plasticity (BSP model combined with Biot’s consolidation theory is employed to simulate the cyclic loading induced elasto-plastic deformation of the soil skeleton and the accompanying generation/dissipation of the excess pore water pressure. The suction force generated around the anchor due to the cyclic variation of the pore water pressure has much effect on the pullout capacity of the plate anchor. The calculated pullout capacity with the proposed method (i.e., the coupled analysis gets lower than that with the conventional total stress analysis for the case of long-term sustained loading, but slightly higher for the case of short-term monotonic loading. The cyclic loading induced accumulation of pore water pressure may result in an obvious decrease of the stiffness of the soil-plate anchor system.
Energy Technology Data Exchange (ETDEWEB)
Shakouchih, T. [Mie University, Mie (Japan). Faculty of Engineering; Matsumoto, A.; Watanabe, A.
2000-10-25
It is well known that as decreasing the nozzle to plate spacing considerably the heat transfer coefficient of circular impinging jet, which impinges to the plate normally, increases remarkably. At that time, the flow resistance of nozzle-plate system also increases rapidly. In this study, in order to reduce the flow resistance and to enhance the heat transfer coefficient of the circular impinging jet with a considerably low nozzle to plate spacing, a special nozzle with notches is proposed, and considerable improvement of the flow and heat transfer properties are shown. The mechanism of enhancement of the heat transfer properties is also discussed. (author)
Scattering of guided SH_wave by a partly debonded circular cylinder in a traction free plate
Institute of Scientific and Technical Information of China (English)
WANG; Xiaomin
2001-01-01
Techniques, 1969, MTT_17(3): 148.［14］Wang, X.M.C., Ying, F., Li, M.X., Scattering of antiplane shear wave by a circular cylinder in a traction free plate, submitted to J.Acoust.Soc.Am.［15］Auld, B.A., Acoustic Fields and Waves in Solids, Vol Ⅱ, New York: John Wiley & Sons, 1973, 73-160.［16］Bostrom, A., Elastic wave scattering from an interface crack: antiplane strain, J.Appl.Mech., 1987, 54(2): 503.
Institute of Scientific and Technical Information of China (English)
2008-01-01
This paper studies the problem of a functionally graded piezoelectric circular plate subjected to a uniform electric potential difference between the upper and lower surfaces. By assuming the generalized displacements in appropriate forms,five differential equations governing the generalized displacement functions are derived from the equilibrium equations. These displacement functions are then obtained in an explicit form,which still involve four undetermined integral constants,through a step-by-step integration which properly incorporates the boundary conditions at the upper and lower surfaces. The boundary conditions at the cylindrical surface are then used to determine the integral constants. Hence,three-dimen sional analytical solutions for electrically loaded functionally graded piezoelectric circular plates with free or simply-supported edge are completely determined. These solutions can account for an arbitrary material variation along the thickness,and thus can be readily degenerated into those for a homogenous plate. A numerical example is finally given to show the validity of the analysis,and the effect of material inhomogeneity on the elastic and electric fields is discussed.
Norgren, Martin
2009-01-01
The capacitance of the circular parallel plate capacitor is calculated by expanding the solution to the Love integral equation into a Fourier cosine series. Previously, this kind of expansion has been carried out numerically, resulting in accuracy problems at small plate separations. We show that this bottleneck can be alleviated, by calculating all expansion integrals analytically in terms of the Sine and Cosine integrals. Hence, we can, in the approximation of the kernel, use considerably larger matrices, resulting in improved numerical accuracy for the capacitance. In order to improve the accuracy at the smallest separations, we develop a heuristic extrapolation scheme that takes into account the convergence properties of the algorithm. Our results are compared with other numerical results from the literature and with the Kirchhoff result. Error estimates are presented, from which we conclude that our results is a substantial improvement compared with earlier numerical results.
Institute of Scientific and Technical Information of China (English)
Huang Xiujie; Zhang Jixun; Yang Ling; Yang Shikou; Wang Xingli
2016-01-01
The present paper aims to establish a versatile strength theory suitable for elasto-plastic analysis of underground tunnel surrounding rock. In order to analyze the effects of intermediate principal stress and the rock properties on its deformation and failure of rock mass, the generalized nonlinear unified strength theory and elasto-plastic mechanics are used to deduce analytic solution of the radius and stress of tunnel plastic zone and the periphery displacement of tunnel under uniform ground stress field. The results show that: intermediate principal stress coefficient b has significant effect on the plastic range, the magnitude of stress and surrounding rock pressure. Then, the results are compared with the unified strength criterion solution and Mohr–Coulomb criterion solution, and concluded that the generalized nonlinear unified strength criterion is more applicable to elasto-plastic analysis of underground tunnel surrounding rock.
Study of electroless copper plating on ABS plastic%ABS塑料化学镀铜的研究
Institute of Scientific and Technical Information of China (English)
秦建芳; 姚陈忠; 曹新录
2012-01-01
The basic process of electroless copper plating was discussed using ABS plastic as a matrix,formaldehyde as a reducing agent and EDTA as a complexing agent It was sudied for the bath pH, plating temperature and plating time. The optimum process parameters were identified that they were temperature being 50℃, the optimum pH value being 12. S and plating time being 40 min. the composition and morphology of the copper layer under optimal conditions were analyzed by X-ray diffraction and SEM. The results showed that:the copper coating was hongliang appearance,surface roughness,and few impurities.%以ABS塑料为基体,甲醛为还原剂,EDTA为络合剂,研究了化学镀铜的基本工艺.考察镀液的pH值、温度、时间对镀铜的影响,确定最佳工艺参数为pH=12.5、T=50℃、t=40min.通过扫描电镜和X射线衍射分析了最佳条件下镀铜层的形貌和成分,结果表明:该镀层外观红亮,表面平整,杂质含量很少.
Institute of Scientific and Technical Information of China (English)
吴桂英; 梁利平; 李鑫
2009-01-01
运用ANSYS/LS-DYNA软件对TNT炸药爆炸后,空气冲击波作用下弹塑性圆板的动力反直观行为进行了数值模拟. 采用任意拉格朗日-欧拉算法(ALE算法),将炸药、空气和板进行有限元离散,在考虑材料屈服极限及应变率效应对动力反直观行为影响的情况下,分别取全模型和1/4模型进行比较. 结果表明,用ALE流-固耦合方法研究爆炸载荷作用下结构反直观行为是行之有效的;材料性能、板厚度对动力反直观行为有较大影响,只有材料的屈服极限较低且厚度较薄的板,容易发生反直观行为;同时,在数值分析时需要考虑应变率的效应.%Anomalous response of elastic-plastic circular plate subjected to TNT air blast loading is studied using LS-DYNA as the numerical tool. TNT. air and plate are taken as varied finite elements with ALE arithmetic comparing full model and 1/4 model. Yield stress and strain rate have been considered for anomalous responses. It is found by numerical analyses that ALE arithmetic is a better method for structural anomalous dynamic behavior under blast loading. Material parameters and the thickness of the plate have influence on anomalous response. Anomalous response of the plate appeared easily when yield stress is lower and the thickness of plate thinner. Strain rate should be considered for numerical simulation of anomalous response under blast loading.
Chen, Ran; Tonon, Fulvio
2011-03-01
The paper presents a closed-form solution for the convergence curve of a circular tunnel in an elasto-brittle-plastic rock mass with both the Hoek-Brown and generalized Hoek-Brown failure criteria, and a linear flow rule, i.e., the ratio between the minor and major plastic strain increments is constant. The improvement over the original solution of Brown et al. (J Geotech Eng ASCE 109(1):15-39, 1983) consists of taking into account the elastic strain variation in the plastic annulus, which was assumed to be fixed in the original solution by Brown et al. The improvement over Carranza-Torres' solution (Int J Rock Mech Min Sci 41(Suppl 1):629-639, 2004) consists of providing a closed-form solution, rather than resorting to numerical integration of an ordinary differential equation. The presented solution, by rigorously following the theory of plasticity, takes into account that the elastic strain components change with radial and circumferential stress changes within the plastic annulus. For the original Hoek-Brown failure criterion, disregarding the elastic strain change leads to underestimate the convergence by up to 55%. For a rock mass failing according to the generalized Hoek-Brown failure criterion, using the original failure criterion leads to a high probability (97%) of underestimating the convergence by up to 100%. As a consequence, the onset or degree of squeezing may be underestimated, and the loading on the support/reinforcement calculated with the convergence/confinement method may be largely underestimated.
Analysis of Plasticity, Fracture and Friction in Steady State Plate Cutting
DEFF Research Database (Denmark)
Simonsen, Bo Cerup; Wierzbicki, Tomasz
1996-01-01
A closed form solution to the problem of steady state wedge cutting through a ductile metal plate is presented. The considered problem is an idealization of a ship bottom raking process, i.e. a continuous cutting damage of a ship bottom by a hard knife-like rock in a grounding event. A new...
Roellig, Daniela; Tan-Cabugao, Johanna; Esaian, Sevan; Bronner, Marianne E
2017-03-29
The 'neural plate border' of vertebrate embryos contains precursors of neural crest and placode cells, both defining vertebrate characteristics. How these lineages segregate from neural and epidermal fates has been a matter of debate. We address this by performing a fine-scale quantitative temporal analysis of transcription factor expression in the neural plate border of chick embryos. The results reveal significant overlap of transcription factors characteristic of multiple lineages in individual border cells from gastrula through neurula stages. Cell fate analysis using a Sox2 (neural) enhancer reveals that cells that are initially Sox2+ cells can contribute not only to neural tube but also to neural crest and epidermis. Moreover, modulating levels of Sox2 or Pax7 alters the apportionment of neural tube versus neural crest fates. Our results resolve a long-standing question and suggest that many individual border cells maintain ability to contribute to multiple ectodermal lineages until or beyond neural tube closure.
Xue, Mianqiang; Li, Jia; Xu, Zhenming
2012-03-06
Metal-plated plastics (MPP), which are important from the standpoint of aesthetics or even performance, are increasingly employed in a wide variety of situations in the automotive industry. Serious environmental problems will be caused if they are not treated appropriately. Therefore, recycling of MPP is an important subject not only for resource recycling but also for environmental protection. This work represents a novel attempt to deal with the MPP. A self-designed hammer crusher was used to liberate coatings from the plastic substrate. The size distribution of particles was analyzed and described by the Rosin-Rammler function model. The optimum retaining time of materials in the crusher is 3 min. By this time, the liberation rate of the materials can reach 87.3%. When the density of the suspension is 31,250 g/m(3), the performance of liberation is the best. Two-step magnetic separation was adopted to avoid excessive crushing and to guarantee the quality of products. Concerning both the separation efficiency and grade of products, the optimum rotational speed of the magnetic separator is 50-70 rpm. On the basis of the above studies about the liberating and separating behavior of the materials, a continuous recycling system (the technology of crush-magnetic separation) is developed. This recycling system provides a feasible method for recycling MPP efficiently, economically, and environmentally.
Directory of Open Access Journals (Sweden)
Jimit R Patel
2014-12-01
Full Text Available Efforts have been made to analyze the Shliomis model based ferrofluid lubrication of a squeeze film between rotating rough curved circular plates where the upper plate has a porous facing. Different models of porosity are treated. The stochastic modeling of Christensen and Tonder has been employed to evaluate the effect of surface roughness. The related stochastically averaged Reynolds type equation is numerically solved to obtain the pressure distribution, leading to the calculation of load carrying capacity. The results presented in graphical form establish that the Kozeny-Carman model is more favorable as compared to the Irmay one from the design point of view. It is observed that the Shliomis model based ferrofluid lubrication performs relatively better than the Neuringer-Rosensweig one. Although the bearing suffers due to transverse surface roughness, with a suitable choice of curvature parameters and rotational ratio, the negative effect of porosity and standard deviation can be minimized by the ferrofluid lubrication at least in the case of negatively skewed roughness.
DEFF Research Database (Denmark)
Kling, Joyce; Hjulmand, Lise-Lotte
2008-01-01
’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through......Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...
DEFF Research Database (Denmark)
Kling, Joyce; Hjulmand, Lise-Lotte
2008-01-01
Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty......’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...
Roellig, Daniela; Tan-Cabugao, Johanna; Esaian, Sevan; Bronner, Marianne E
2017-01-01
The ‘neural plate border’ of vertebrate embryos contains precursors of neural crest and placode cells, both defining vertebrate characteristics. How these lineages segregate from neural and epidermal fates has been a matter of debate. We address this by performing a fine-scale quantitative temporal analysis of transcription factor expression in the neural plate border of chick embryos. The results reveal significant overlap of transcription factors characteristic of multiple lineages in individual border cells from gastrula through neurula stages. Cell fate analysis using a Sox2 (neural) enhancer reveals that cells that are initially Sox2+ cells can contribute not only to neural tube but also to neural crest and epidermis. Moreover, modulating levels of Sox2 or Pax7 alters the apportionment of neural tube versus neural crest fates. Our results resolve a long-standing question and suggest that many individual border cells maintain ability to contribute to multiple ectodermal lineages until or beyond neural tube closure. DOI: http://dx.doi.org/10.7554/eLife.21620.001 PMID:28355135
Directory of Open Access Journals (Sweden)
Nitin Jain
2012-10-01
Full Text Available Normal 0 false false false EN-IN X-NONE X-NONE ABSTRACT: A number of analytical and numerical techniques are available for the two dimensional study of stress concentration around the hole(s in isotropic and composite plates subjected to in-plane or transverse loading conditions. The information on the techniques for three dimensional analyses of stress concentration factor (SCF around the hole in isotropic and composite plates subjected to transverse loading conditions is, however, limited. The present work emphasizes on the effect of fibre orientation (q on the stress concentration factor in fibrous composite plates with central circular hole under transverse static loading condition. The work is carried out for cantilever fibrous composite plates. The effects of thickness -to- width (T/A and diameter-to-width (D/A ratios upon SCF at different fibre orientation are studied. Plates of four different composite materials were considered for hole analysis in order to determine the sensitivity of SCF with elastic constants. Deflections in transverse direction were calculated and analysed. All results are presented in graphical form and discussed. The finite element formulation and its analysis were carried out using ANSYS package.ABSTRAK: Terdapat pelbagai teknik analitikal dan numerical untuk kajian tumpuan tegasan dua dimensi di sekeliling lubang-lubang dalam komposit isotropik dan plat pada satah atau keadaan bebanan melintang. Bagaimanapun, maklumat mengenai kaedah analisis tiga dimensi untuk faktor ketumpatan tegasan (SCF sekitar lubang dalam komposit isotropik dan plat pada keadaan bebanan melintang adalah terhad. Kertas ini menekankan kesan orientasi gentian (q pada faktor tumpuan tegasan dalam komposit plat bergentian dengan lubang berpusat di bawah keadaan bebanan melintang. Kajian ini dilkukan untuk cantilever plat komposit bergentian. Kesan ketebalan terhadap kelebaran plat (T/A dan diameter terhadap kelebaran komposit (D/A dengan SCF
Plastic scintillator-based hodoscope for the characterization of large-area resistive plate chambers
Indian Academy of Sciences (India)
V K S KASHYAP; C YADAV; S T SEHGAL; R SEHGAL; R G THOMAS; L M PANT; A K MOHANTY
2016-12-01
A scintillator-based hodoscope is fully operational at Nuclear Physics Division, Bhabha Atomic Research Centre (NPD-BARC). It was used for characterizing the resistive plate chambers (RPCs) assembled for the RE4 upgrade for the compact muon solenoid (CMS) experiment, installed during the long shut-down (LS1) using cosmic muons. It has now been employed for R & D related to gas mixtures and glass RPCs for the Indiabased neutrino observatory (INO) and muon tomography studies. The hodoscope is equipped with gas flow lines,LV, HV and VME-based DAQ with multihit TDCs. CERN-based software was adapted, implemented and along with the cosmic trigger, was used to evaluate the functional parameters for the RPCs, such as efficiency, clustersize etc.
Assessment of the exit defects in carbon fibre-reinforced plastic plates caused by drilling
Energy Technology Data Exchange (ETDEWEB)
Zhang Houjiang; Zhang Liangchi [Sydney Univ. (Australia). Dept. of Mechanical and Mechatronic Engineering; Chen Wuyi; Chen Dingchang [Beijing Univ. of Aeronautics and Astronautics, BJ (China). Dept. of Manufacturing Engineering
2001-07-01
This paper investigates the formation of the exit defects in carbon fibre-reinforced plates and characterizes their features in terms of drilling conditions. It was found that spalling and fuzzing are the major mechanisms of exit defects. The spalling, consisting of a main region and a secondary region, is caused by chisel and cutting edge actions, in which the former plays a key role. The fuzzing, however, exists in the cutting region where the included angle between the fibre direction of the surface layer and that of the cutting speed is acute. A severer spalling damage corresponds to a high spindle speed, a large feed rate and a great thrust force. Some empirical relationships, including a dimensionless formula, were developed for assessing the characteristic dimension of the spalling damage based on the known drilling conditions. (orig.)
Institute of Scientific and Technical Information of China (English)
ZENG Xian-tao; DING Ya-hong; WANG Xing-guo
2006-01-01
The testing of thirteen reinforced concrete (RC) beams strengthened by epoxy-bonded glass fiber reinforced plastic plate (GFRP) shows that the RC beam and the GFRP plate with epoxy bonding on it can work fairly well in coordination to each other. But there is relative slipping between RC beam and GFRP plate. And the strain of GFRP and steel rebar of RC beam satisfies the quasi-plane-hypothesis, that is, the strain of longitudinal fiber that parallels to the neutral axis of plated beam within the scope of effective height (h0) of the cross section is in direct proportion to the distance from the fiber to the neutral axis. The strain of GFRP and steel rebar satisfies the equation: εCFRP = Kεsteel.
Institute of Scientific and Technical Information of China (English)
GUO Zhi-liang; CHENG Min; CAO Guo-yong; LI Hua-zhuang; TENG Hai-jun; ZHOU Yue
2006-01-01
Objective:To compare the phenotype characteristics of rat annulus fibrosus (AF) cells cultured on flexible silicone membranes and those in plastic plates. Methods :The morphology of AF cells cultured in different substrates was examined. Proteoglycan was stained by toluidine blue. Contents of collagen type I , collagen type Ⅱ and aggrecan mRNAs were determined by reverse transcription-polymerase chain reaction (RT-PCR). The expression of integrin β1 was monitored by flow cytometry. By using propidium iodide (PI), the cell cycle in AF cells was analyzed. Cell adhesion to silicone membrane was also measured. Results:The AF cells cultured on different substrates were morphologically undistinguishable.Toluidine blue staining showed that there was also no difference between AF cells cultured on these 2 substrates. They still had the same expression levels of collagen type Ⅰ , collagen type Ⅱ , aggrecan mRNAs,and integrin β1. No significant difference was observed in the distribution of the cell cycle. AF cells grew well on silicone membrane. Conclusion:AF cells cultured on flexible silicone membrane maintain the stability of phenotype and may be appropriate for further studying the metabolic responses to mechanical stimuli at the cellular level.
Rivera, F F; González, I; Nava, J L
2008-08-01
This work shows the application of a rotating cylinder electrode (RCE) in the removal of Cu(II) content from an effluent generated by a plastics chromium-plating industry, on the laboratory scale; in particular, it deals with rinse water from the electrolytic copper process. This process was designed to convert cupric ions in solution to metal powder. The generation of metal powders in the RCE was achieved at Reynolds numbers between 52925 and 83183 and limiting current densities (J(L)) in the range of 17 to 25 mA cm(-2). The removal of Cu(II) (initially 922 ppm) reached 43 ppm in 10 minutes of electrolysis for Re = 83183 and J = 25 mA cm(-2), with a space-time yield of 88 mg Cu(II) L(-1) min(-1), 95% current efficiency, and energy consumption of 5.3 KWh m(-3). The electrochemical treatment applied to waste rinse water at the RCE allows this treated water to be recycled back to the same rinsing process, avoiding additional consumption and discharge of this liquid.
Li, Dongsheng; Du, Fangzhu; Ou, Jinping
2017-03-01
Glass-fiber reinforced plastic (GFRP)-confined circular concrete-filled steel tubular (CCFT) columns comprise of concrete, steel, and GFRP and show complex failure mechanics under cyclic loading. This paper investigated the failure mechanism and damage evolution of GFRP–CCFT columns by performing uniaxial cyclic loading tests that were monitored using the acoustic emission (AE) technique. Characteristic AE parameters were obtained during the damage evolution of GFRP–CCFT columns. Based on the relationship between the loading curve and these parameters, the damage evolution of GFRP–CCFT columns was classified into three stages that represented different damage degrees. Damage evolution and failure mode were investigated by analyzing the b-value and the ratio of rise time to waveform amplitude and average frequency. The damage severity of GFRP–CCFT columns were quantitatively estimated according to the modified index of damage and NDIS-2421 damage assessment criteria corresponding to each loading step. The proposed method can explain the damage evolution and failure mechanism for GFRP–CCFT columns and provide critical warning information for composite structures.
ABS塑胶真空镀金色氮化锆工艺%Vacuum plating of golden zirconium nitride on ABS plastic surface
Institute of Scientific and Technical Information of China (English)
雷大法
2014-01-01
介绍了ABS塑胶制品表面真空镀金黄色氮化锆镀层的工艺，主要包括除油、亲水、粗化、中和、预浸、沉钯、解胶、碱性镀镍、焦磷酸盐镀铜、硫酸盐镀铜、镀镍、镀铬和真空镀氮化锆。采用该工艺制备的氮化锆镀层为光亮的金黄色，结合力、硬度和耐蚀性等性能满足不同环境的正常使用要求，可应用于家电和电子产品领域。%A process for vacuum plating of golden yellow zirconium nitride coating on the surface of ABS plastic product was introduced. The process flow is mainly composed of degreasing, hydrophilizing, roughening, neutralizing, pre-impregnation, palladium activation, acceleration, alkaline nickel plating, pyrophosphate copper plating, sulfate copper plating, nickel plating, chromium plating, and zirconium nitride vacuum plating. The zirconium nitride coating prepared by the given process is bright golden yellow and has qualified adhesion, hardness, and corrosion resistance for normal use in different environments, and can be applied to the production of household appliances and electronic products.
Energy Technology Data Exchange (ETDEWEB)
Haneda, Y.; Kurasawa, H. (Nagano National College of Technology, Nagano (Japan)); Tsuchiya, Y. (Shinshu Univ., Nagano (Japan). Faculty of Engineering); Suzuki, K. (Kyoto Univ., Kyoto (Japan). Faculty of Engineering)
1994-04-25
The flow field and heat transfer around a circular cylinder is investigated experimentally when two dimensional jet is impinged on a circular cylinder mounted near two flat plates which are set at a fixed inclination against the axis of jet. Flow field varies markedly depending on whether the minimum channel width is the minimum space B between the flat plates or the space C between the cylinder and the plates. The local Nusselt number of the cylinder strongly depends on the value of space C between the cylinder and the plates. The minimum and maximum locations correspond to the locations of separation and reattachment, respectively, of the flow around the cylinder. When the ratio between the nozzle-to-cylinder distance L and the short side h of the nozzle is 3 (L/h=3), the mean Nusselt number around the cylinder becomes the maximum when C/D is 0.1 where D is the diameter of the cylinder, and increases by about 9 to 12% as compared with the case where no plate is provided. For L/h=7 and L/h=10, the mean Nusselt number does not increase distinctly as compared with the case where no flat plate is provided. 16 refs., 15 figs.
Département des Ressources humaines
2004-01-01
Administrative Circular N° 2 (Rev. 2) - May 2004 Guidelines and procedures concerning recruitment and probation period of staff members This circular has been revised. It cancels and replaces Administrative Circular N° 2 (Rev. 1) - March 2000. Administrative Circular N° 9 (Rev. 3) - May 2004 Staff members contracts This circular has been revised. It cancels and replaces Administrative Circular N° 9 (Rev. 2) - March 2000. Administrative Circular N° 26 (Rev. 4) - May 2004 Procedure governing the career evolution of staff members This circular has also been revised. It Administrative Circulars Administrative Circular N° 26 (Rev. 3) - December 2001 and brings up to date the French version (Rev. 4) published on the HR Department Web site in January 2004. Operational Circular N° 7 - May 2004 Work from home This circular has been drawn up. Operational Circular N° 8 - May 2004 Dealing with alcohol-related problems...
Rosu, Grigore; Goguen, Joseph; Norvig, Peter (Technical Monitor)
2001-01-01
Circular coinduction is a technique for behavioral reasoning that extends cobasis coinduction to specifications with circularities. Because behavioral satisfaction is not recursively enumerable, no algorithm can work for every behavioral statement. However. algorithms using circular coinduction can prove every practical behavioral result that we know. This paper proves the correctness of circular coinduction and some consequences.
Institute of Scientific and Technical Information of China (English)
李银山; 刘波; 张明路; 段国林
2011-01-01
计及材料的非线性弹性,建立圆板自由振动的非线性动力学方程.采用Galerkin法,将圆板的非线性动力学偏微分方程简化成四种标准类型的二次非线性微分方程.提出一类强非线性动力系统的初值变换法,将描述动力系统的二阶常微分方程,化为以角频率、振幅和偏心距为独立变量的不完备非线性代数方程组,考虑初始条件补充约束方程,构成频率、振幅和偏心距为变量的完备非线性代数方程组.利用Maple程序可以方便地求解.结果表明,初值变换法不仅适合于对称振动问题,而且适合于非对称振动问题.首次给出二次非线性自由振动的偏一频曲线.%The nonlinear dynamic equation of free vibration of a circular plate is derived with nonlinear theory of elasticity. By using Calerkin' g method, the governing partial differential equation was reduced to four standard types of quadratic nonlinear ordinary ones. A method of initial-value transformation is presented for a class strongly nonlinear dynamic system. By using Ritz-Galerkin s method , an oscillation system governed by a set of second order ordinary differential equations, can be transformed into a set of incomplete non-linear algebraic equations with angular frequencies, amplitudes and central offsets as independent variables. Then, by supplement of some initial-value restrictions, the incomplete equations can be made complete, obtaining a set of non-linear algebraic equations with angular frequencies, amplitudes and central offsets, which can be solved conveniently by Maple program. Hie results show that the method of initial-value transformation can solve not only symmetry problems, but also asymmetry problems for free vibration. The offset-angular frequency backbone curves of quadratic nonlinear equations were presented for the first time.
Institute of Scientific and Technical Information of China (English)
李清禄; 张靖华; 李世荣
2016-01-01
The free vibration of FGMmoderately thick circular plates was investigated.A FGM plate consisting of metal and ceramic was considered in the study.Based on the geometric equation,physical equation and equilibrium equation of thick plates,taking into account the transverse shearing deformation,the free vibration equation of axisymmetric FGM thick circular plates was derived in terms of the middle surface angles of rotation and lateral displacement.The material properties of the plate were assumed to vary continuously in the thickness direction according to a power law.By using the shooting method to solve the coupled ordinary differential equations with different boundary conditions,the natural frequencies of FGMthick circular plates were obtained numerically.The effects of material gradient property,thickness ratio and boundary conditions on the natural frequencies were discussed in detail.%研究了由陶瓷和金属两种材料组成的功能梯度材料（FGM）中厚圆板的自由振动问题。基于考虑横向剪切变形中厚板的几何方程、物理方程及平衡方程，建立了以中面转角和横向位移为基本未知量的功能梯度中厚圆板轴对称自由振动问题的控制方程；假定功能梯度中厚圆板的材料性质方向按照幂函数连续变化规律；采用打靶法数值求解所得非线性两点边值问题出，获得了多种边界下功能梯度中厚圆板的无量纲自然频率以及振动模态。讨论了材料梯度指数、板的厚度以及边界条件对自然频率的影响。
The Experimental Study of Plastic Plate Solar Collector%塑料太阳能平板集热器试验研究
Institute of Scientific and Technical Information of China (English)
李久锋; 陈观生; 张国庆
2015-01-01
According to the undemanding heating rate of heat-storage solar water heater, a new type of plastic plate solar collector was designed.Under the condition of intermittent forced circulation, test on the performance of this collector was carried out and instantaneous efficiency curves were obtained.As a result, the average daily collector efficiency is 51%~55% and the temperature of tank is 45.8~50.2 ℃, which serve as a reference for the application of plastic plate solar collector.%针对蓄热型太阳能热水器对升温速率要求不高的特点，提出并研制了一种新型塑料太阳能平板集热器．在间歇性强制循环条件下，对该集热器进行性能测试，获得了瞬时效率曲线．在试验条件下，该集热器的日平均效率为51％～55％，水箱温度为45．8～50．2℃，可以为塑料平板集热器的实际应用提供依据．
Energy Technology Data Exchange (ETDEWEB)
Wang, Ming-Qiu, E-mail: mqwang1514@163.com; Yan, Jun; Du, Shi-Guo; Li, Hong-Guang
2013-07-15
A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via N-Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni–P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni–P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.
Wang, Ming-Qiu; Yan, Jun; Du, Shi-Guo; Li, Hong-Guang
2013-07-01
A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via Nsbnd Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni-P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni-P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.
Energy Technology Data Exchange (ETDEWEB)
Yamamoto, M.; Yao, T.; Yajima, H.; Miyamoto, H.; Morita, S. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering; Ogihara, Y.; Ishikawa, T. [Nippon Steel Corp., Tokyo (Japan)
1996-10-01
Buckling and plastic breakdown strength characteristics of a structure fabricated by using new steel plates with surface layer made into ultra fine grain structure were analyzed and discussed by using a belt plate buckling and plasticity test and the finite element method. The tested steel plate has a thickness of 25 mm, and was fabricated for ocean vessel use, with surface layers on both sides of about 1/6 of the whole thickness having been made an ultra fine grain structure. As a result of a belt steel buckling and plasticity test on a steel plate with surface ratio of 29%, both of the initial yield stress and the buckling stress were found increased by about 4 to 10% as compared with a steel plate having surface ratio of 0%. An analysis by using the finite element method was made on square steel plates with a length of 80 cm, a width of 100 cm, and thicknesses of 12 mm and 24 mm. A result was obtained that, in the case of surface layer ratio of 33%, both of the initial yield stress and the maximum load withstanding force were higher by 5 to 16% than the case of surface ratio of 0%. Similar rise in strength was shown also in bend preventing plates which are basic constituting members of a vessel. 6 refs., 10 figs., 2 tabs.
Treatment of plastic Titanium plate on fixation of calcaneal fractures%可塑钛板内固定治疗跟骨骨折
Institute of Scientific and Technical Information of China (English)
崔庆元
2011-01-01
Objective To investigate the plastic plate fixation of calcaneal fractures. Methods Totally 22 patients, 18 males, 10 cases of left foot, right foot 7 cases in which both feet 1 female 4 cases , 3 cases of left foot right foot in 1 case. The average age of 22 -44 years old 33 years old. Are fall injuries. Are blunt trauma, the use of L - shaped lateral calcaneal incision subperiosteal dissection to expose the subtalar and calcaneocuboid joints, so Bohler recovery to 30° angle or so, with a plastic titanium plate. Results After 2 feet skin flap with partial necrosis of subcutaneous infection in which a foot, some exposed steel, dressing healed. Patients were followed up using Maryland foot score excellent joint function rate of 88%. Conclusions Plastic plate fixation of calcaneal fractures, if done correctly, results are quite satisfactory.%目的 探讨可塑钛板内固定治疗跟骨骨折.方法 本组22例,男性18例,左足10例,右足7例,其中双足1例,女性4例,左足3例,右足1例.年龄22 ～44岁,平均33岁.均为坠落伤.均为闭合性损伤,采用跟骨外侧L型切口骨膜下剥离,显露距下关节及跟骰关节,使B(o)hler角恢复至30°左右,用可塑钛合金钢板固定.结果 术后两足切口皮缘有部分坏死其中1足出现皮下感染,钢板部分外露,换药愈合.术后随访采用Maryland足部评分法关节功能优良率达88％.结论 可塑钛板内固定治疗跟骨骨折,只要方法得当,效果十分理想.
Institute of Scientific and Technical Information of China (English)
任红军; 韩清凯
2012-01-01
研究了在广义弹性简支边界条件下的具有硬涂层的圆盘构件的自由振动的量纲一固有频率的精确解.首先利用多铁性多层圆盘的解析分析的多层板弹性理论,导出带硬涂层的圆盘结构的状态方程,其中以位移、电势、磁势、应力、电位移和磁感应强度为状态变量.利用有限Hankel变换和传播矩阵法,得到考虑压电和压磁效应的带硬涂层的圆盘的量纲一固有频率的精确解.根据算例结果,比较了压电、压磁两类硬涂层材料在单面涂层、双面涂层和不同涂层厚度的结构配置下的固有频率变化规律.%Under the broad-elasticity simply-supported boundary conditions, the exact solution on dimensionless inherent frequency of hard-coating circular plates is investigated via the free vibration. Pertaining to the literatures of multi-layered plate elastic theory about the analytical analysis on multi-ferrous and multi-layered circular plates, the state equation of hard-coating circular plate is deduced. Amongst this equation, the displacement, electric potential, magnetic potential, stress, electric displacement and magnetic induction density are treated as state variables. By applying the limited Hankel transform and propagation matrix, the exact solution is obtained with consideration of the piezoelectric and piezomagnetic effects. Based on the computational example results, in comparison with two hard-coating materials as well as single-sided and double-sided coating structures, the changing principle of inherent frequency is detected regarding coating thickness.
Energy Technology Data Exchange (ETDEWEB)
Srithar, K. [Department of Mechanical Engineering, Thiagarajar College of Engineering, Madurai 625 015 (India); Mani, A. [Department of Mechanical Engineering, Indian Institute of Technology, Madras, Chennai 600 036 (India)
2007-12-15
Presently, tanneries in Tamilnadu, India are required to segregate the effluent of soaking and pickling sections from other wastewater streams and send it to shallow solar pans for evaporation to avoid land pollution. A large area of solar pans is required for evaporating the water in the effluent at salt concentration in the range of 4-5%. An experimental study has been made by using fibre reinforced plastic flat plate collector (FRP-FPC) and spray system in a pilot plant with a capacity to handle 5000 l per day, which increases the evaporation rate. After increasing the salt concentration level to near saturation limit, the concentrated liquid was sent to conventional solar pans for its continued evaporation and recovery of salt. In this improved system, the rate of evaporation was found to be 30-40% more than that in the conventional solar pans. The performance is compared with the theoretically simulated performance. (author)
Hyer, M. W.; Lee, H. H.
1990-01-01
The gains in buckling performance are explored that can be achieved by deviating from the conventional straightline fiber format and considering the situation whereby the fiber orientation in a layer, or a group of layers, can vary from point to point. The particular situation studied is a simply supported square plate with a centrally located hole loaded in compression. By using both a sensitivity analysis and a gradient-search technique, fiber orientation in a number of regions of the plate are selected so as to increase the buckling load relative to baseline straightline designs. The sensitivity analysis is used to determine which regions of the plate have the most influence on buckling load, and the gradient search is used to find the design that is believed to represent the absolute maximum buckling load for the conditions prescribed. Convergence studies and sensitivity of the final design are discussed. By examining the stress resultant contours, it is shown how the curvilinear fibers move the load away from the unsupported hole region of the plate to the supported edges, thus increasing the buckling capacity. The tensile capacity of the improved buckling design is investigated, and it is shown that both tensile capacity and buckling capacity can be improved with the curvilinear fiber concept.
Park, Soo-Jin; Jang, Yu-Sin; Rhee, Kyong-Yop
2002-01-15
In this work, a new method based on nanoscaled Ni-P alloy coating on carbon fiber surfaces is proposed for the improvement of interfacial properties between fibers and epoxy matrix in a composite system. Fiber surfaces and the mechanical interfacial properties of composites were characterized by atomic absorption spectrophotometer (AAS), scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS), interlaminar shear strength (ILSS), and impact strength. Experimental results showed that the O(1s)/C(1s) ratio or Ni and P amounts had been increased as the electroless nickel plating proceeded; the ILSS had also been slightly improved. The impact properties were significantly improved in the presence of Ni-P alloy on carbon fiber surfaces, increasing the ductility of the composites. This was probably due to the effect of substituted Ni-P alloy, leading to an increase of the resistance to the deformation and the crack initiation of the epoxy system.
Institute of Scientific and Technical Information of China (English)
蔡艳青; 邵永波
2011-01-01
为了研究环口板加固对T型圆钢管节点滞回性能的影响,运用有限元方法对环口板加固T型圆钢管节点进行了滞回性能的参数分析.参数包括支管直径与主管直径比β,主管直径与2倍主管壁厚的比γ,环口板厚度与主管管壁厚之比γc,和环口板长度与支管直径之比lc／d1.有限元分析结果表明:环口板加固T型圆钢管节点的滞回性能相对于未加固节点得到了很大的改善.参数β和γ对节点的滞回性能有显著影响.为了改善节点的滞回性能,建议环口板的厚度不宜超过主管厚度的1.5倍,环口板的长度不宜超过支管直径的2倍.%To study the hysteretic performance of circular tubular T-joints with collar plate reinforcement, a parametric analysis is conducted by using the finite element method. The parameters include; the brace-to-chord diameter ratio β, chord radius to twice chord wall thickness ratio y, collar-plate to chord wall thickness ratio tc , and collar-plate length to brace diameter ratio lc/dl. It is found that the hysteretic behaviour of collar plate reinforced T-joints has been greatly improved compared to that of the un-reinforced T-joints. In addition, the parameters y and ^8 have significant effect on the hysteretic behaviour. It can be suggested that the thickness of collar plate should not exceed 1. 5 times of the chord thickness, and the length of collar plate also should not exceed 2 times of the brace diameter for improving the hysteretic performance efficiently.
National Oceanic and Atmospheric Administration, Department of Commerce — Circular Updates are periodic sequentially numbered instructions to debriefing staff and observers informing them of changes or additions to scientific and specimen...
High performance 3D printed electronics using electroless plated copper
Jian, Jin Rong; Kim, Taeil; Park, Jae Sung; Wang, Jiacheng; Kim, Woo Soo
2017-03-01
This paper presents design and performance validation of 3D printed electronic components, 3D toroidal air-core inductors, fabricated by multi-material based Fused Deposition Modelling (FDM) 3D printing technology and electroless copper plating. Designs of toroidal inductor is investigated with different core shapes and winding numbers; circular and half-circular cores with 10 and 13 turns of windings. Electroless plated copper thin film ensures 3D printed toroidal plastic structures to possess inductive behaviors. The inductance is demonstrated reliably with an applied source frequency from 100 kHz to 2 MHz as designs vary. An RL circuit is utilized to test the fabricated inductors' phase-leading characteristics with corresponding phase angle changes.
High performance 3D printed electronics using electroless plated copper
Directory of Open Access Journals (Sweden)
Jin Rong Jian
2017-03-01
Full Text Available This paper presents design and performance validation of 3D printed electronic components, 3D toroidal air-core inductors, fabricated by multi-material based Fused Deposition Modelling (FDM 3D printing technology and electroless copper plating. Designs of toroidal inductor is investigated with different core shapes and winding numbers; circular and half-circular cores with 10 and 13 turns of windings. Electroless plated copper thin film ensures 3D printed toroidal plastic structures to possess inductive behaviors. The inductance is demonstrated reliably with an applied source frequency from 100 kHz to 2 MHz as designs vary. An RL circuit is utilized to test the fabricated inductors’ phase-leading characteristics with corresponding phase angle changes.
Baek, Tae Hyun
Photoelasticity is one of the most widely used whole-field optical methods for stress analysis. The technique of birefringent coatings, also called the method of photoelastic coatings, extends the classical procedures of model photoelasticity to the measurement of surface strains in opaque models made of any structural material. Photoelastic phase-shifting method can be used for the determination of the phase values of isochromatics and isoclinics. In this paper, photoelastic phase-shifting technique and conventional Babinet-Soleil compensation method were utilized to analyze a specimen with a triangular hole and a circular hole under bending. Photoelastic phase-shifting technique is whole-field measurement. On the other hand, conventional compensation method is point measurement. Three groups of results were obtained by phase-shifting method with reflective polariscope arrangement, conventional compensation method and FEM simulation, respectively. The results from the first two methods agree with each other relatively well considering experiment error. The advantage of photoelastic phase-shifting method is that it is possible to measure the stress distribution accurately close to the edge of holes.
2003-01-01
Operational Circular N° 4 - April 2003 Conditions for use by members of the CERN personnel of vehicles belonging to or rented by CERN - This circular has been drawn up. Operational Circular N° 5 - October 2000 Use of CERN computing facilities - Further details on the personal use of CERN computing facilities Operational Circular N° 5 and its Subsidiary Rules http://cern.ch/ComputingRules defines the rules for the use of CERN computing facilities. One of the basic principles governing such use is that it must come within the professional duties of the user concerned, as defined by the user's divisional hierarchy. However, personal use of the computing facilities is tolerated or allowed provided : a) It is in compliance with Operational Circular N° 5 and not detrimental to official duties, including those of other users; b) the frequency and duration is limited and there is a negligible use of CERN resources; c) it does not constitute a political, commercial and/or profit-making activity; d) it is not...
Institute of Scientific and Technical Information of China (English)
周婉真
2015-01-01
The author discussed the engineering geological conditions of Fuzhou section(1st-stage)of Minjiang River Flood Protection Project and the working principle of soft foundation treatment with plastic drainage plates. An introduction was made on the material of plastic drainage plate, the construction machine, technical program, monitoring method and construction quality control measures.%论述了闽江防洪工程福州段（一期）工程的工程地质情况及塑料排水板处理软土地基的工作原理。介绍了塑料排水板的材料、施工机械、工艺流程、监测方法和施工质量控制措施。
DEFF Research Database (Denmark)
Han, Yi-Neng; Xia, Shengqiang; Zhang, Yuan-Yuan
2017-01-01
Circular RNAs (circRNAs) are a novel type of universal and diverse endogenous noncoding RNAs (ncRNAs) and they form a covalently closed continuous loop without 5' or 3' tails unlike linear RNAs. Most circRNAs are presented with characteristics of abundance, stability, conservatism, and often exhi...
Energy Technology Data Exchange (ETDEWEB)
Yao, T.; Fujikubo, M.; Yanagihara, D. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering
1996-04-10
A hull structure is constituted by thin panels, and reinforced longitudinally and laterally by stiffened members to increase the effectiveness of the structure. In order to attain findings on buckling and plastic collapse behavior of stiffened plates, this paper describes analysis of elasto-plastic large deflection by using the finite element method on thin stiffened plates having flat-bars and angle-bars. The analysis includes the case of an aspect ratio being 5.0 and the case to consider welding residual stress. Considerations were given on cross sectional shape, panel aspect ratio and effects of initial welding imperfections against the buckling and plastic collapse behavior of the stiffened plates. The angle-bars tend to cause secondary buckling more easily because it has greater bending and twisting rigidity, and stronger constraint against deflection than the flat-bars. When the aspect ratio is larger and the span is longer, the ultimate strength declines, and the withstand power after the ultimate strength decreases rapidly. Existence of the residual stress tends to make the secondary buckling occur more easily. The secondary buckling affects little the withstand power after the ultimate strength. 3 refs., 7 figs., 1 tab.
Division des ressources humaines
2000-01-01
N° 2 (Rev. 1) - March 2000Guidelines and procedures concerning recruitment and probation period of staff membersN° 9 (Rev. 2) - March 2000Staff members contractsN° 16 (Rev. 2) - January 2000TrainingN° 30 (Rev. 1) - January 2000Indemnities and reimbursements upon taking up appointment and termination of contractN° 32 - February 2000Principles and procedures governing complaints of harassmentThese circular have been amended (No 2, N° 9, N° 16 and N° 30) or drawn up (N° 32).Copies are available in the Divisional Secretariats.Note:\tAdministrative and operational circulars, as well as the lists of those in force, are available for consultation in the server SRV4_Home in the Appletalk zone NOVELL (as GUEST or using your Novell username and password), volume PE Division Data Disk.The Word files are available in the folder COM, folder Public, folder ADM.CIRC.docHuman Resources DivisionTel. 74128
Calculations of circular waveguide with a rectangular metal insert.
Directory of Open Access Journals (Sweden)
Yu. K. Sydoruk
2010-05-01
Full Text Available Calculated and analyzed the basic parameters of electromagnetic wave in a circular waveguide with a rectangular metal plate in the following cases: when the circular waveguide without metal plate for a H11 wave of subcritical, critical and supercritical. For calculations was used a finite element method and Ansoft HFSS program.
圆环形薄板大挠度变形有限元分析比较研究%Comparative Study of Finite Element of Large Deflection of Circular Thin Plates
Institute of Scientific and Technical Information of China (English)
陈杰平; 李进; 乔印虎
2016-01-01
Annular thin plate is an important part of automobile shock absorber,which belongs to the typical non-linear deformation of large deflection. Traditional calculation method will cause large errors,or complicated cal-culation which can not be used in engineering conveniently. With the aid of and modern engineering analysis software,the large deflection of circular thin plate of different shock absorbers specifications were studied using the method of finite element analysis. According to von Kármán differential equation,combining with Chien per-turbation method,the analytical expression of the large deflection were presented. Undetermined coefficients of the analytical expression were been fitting out. For different situations,such as fixed radial ratio,or inner/out-side diameter,the calculation analysis and error comparison were carried out. Numerical calculation showed that the method is reasonable and reliable,simple and quick,with an error below 3%,and precision is higher,which can meet with the needs of engineering design and analysis.%环形薄板是汽车减振器中的一个重要零件，属于典型的大挠度非线性变形，传统的计算方法要么产生误差较大，或者计算繁琐不利于工程应用。本文借助于现代分析软件，利用有限元分析方法对汽车减振器中不同规格环形薄板的大挠度变形情况进行了研究。根据von Kármán提出的微分方程，结合钱氏摄动法给出了求解大挠曲变形的解析表达式，拟合出了解析式中的待定系数的数学表达式，并针对固定半径比、内/外径等不同情况进行了计算分析和误差比较。数值计算证明，使用的方法合理可靠，求解精度高、简单快捷实用，误差在3％以下，完全可以满足工程设计分析的需要。
Institute of Scientific and Technical Information of China (English)
李大川; 朱庆鹏; 崔双科; 同帜; 周乃然
2012-01-01
以α-Al2O3为骨料,羧甲基纤维素作为成孔剂,高岭土、TiO2作为高温粘结剂和烧结助剂,采用干压成型工艺和固态粒子烧结法制备出了圆板型多孔α-Al2O3陶瓷膜支撑体（=50 mm,厚度为2 mm）。研究了成孔剂用量、高温粘结剂和烧结助剂的用量、烧结温度因素对支撑体性能的影响。结果表明,制得的支撑体孔隙率在34%以上,孔径在2.23～6.75μm,耐酸碱度在98%以上,机械强度高。%Circular plate-shaped porous ceramic membrane support（diameter of 50 mm,thickness of 2 mm）,with alumina as aggregate,carboxymethylcellulose as pore-fomring agent,kaolin and titanium dioxide as high temperature binder and sintering additive,was prepared by dry-pressing and solid sintering.The effects of the amount of pore-fomring agent,high temperature binder,sintering additive and sintering temperature on the properties of support were studied.The results indicate that support with porosity beyond 34%,pore size between 2.23 and 6.75 μm,acid/ alkali resistance beyond 98% and high mechanical strength was prepared.
Institute of Scientific and Technical Information of China (English)
王珊
2013-01-01
通过引入弯矩函数和恰当的变换，环扇形薄板弯曲问题可导入到二类变量的辛空间，应用分离变量以及辛本征函数展开的数学物理方法进行解析求解。首先，从环扇形薄板弯曲问题的通解出发，讨论了两直边固支，以及一直边自由、另一直边固支边界条件的板，给出了这两种边界条件下相关问题的辛本征解。其次，对相应边界条件下V形切口尖端应力奇异性进行了讨论。环扇形薄板弯曲问题的成功求解再次验证了辛对偶体系方法的有效性。%By introducing bending moment functions and appropriate transformations ,the bending problem of a circular sector thin plate can be led into the symplectic space with two kinds of variables and solved using the methods of mathematical physics of a scheme of separation of variables and symplectic eigenexpansion . Firstly , based on the general solution for the bending problem of the circular sector thin plate ,plates with both straight sides clamped ,and with one straight side free and the other straight side clamped are discussed , and their symplectic eigensolutions are obtained . Secondly ,the stress singularities around the V-shaped notch in a thin plate are analyzed .The validity of methodology of symplectic duality system is verified by the successful solution of bending problem of a circular sector thin plate .
Circular plate capacitor with different disks
Paffuti, Giampiero; Di Lieto, Alberto; Maccarrone, Francesco
2016-01-01
In this paper we write a system of integral equations for a capacitor composed by two disks of different radii, generalizing Love's equation for equal disks. We compute the complete asymptotic form of the capacitance matrix both for large and small distances obtaining a generalization of Kirchhoff's formula for the latter case.
Thomas, R
2006-07-01
The problem of disentangling complex dynamic systems is addressed, especially with a view to identifying those variables that take part in the essential qualitative behaviour of systems. The author presents a series of reflections about the methods of formalisation together with the principles that govern the global operation of systems. In particular, a section on circuits, nuclei, and circular causality and a rather detailed description of the analytic use of the generalised asynchronous logical description, together with a brief description of its synthetic use (OreverseO logic). Some basic rules are recalled, such as the fact that a positive circuit is a necessary condition of multistationarity. Also, the interest of considering as a model, rather than a well-defined set of differential equations, a variety of systems that differ from each other only by the values of constant terms is emphasised. All these systems have a common Jacobian matrix and for all of them phase space has exactly the same structure. It means that all can be partitioned in the same way as regards the signs of the eigenvalues and thus as regards the precise nature of any steady states that might be present. Which steady states are actually present, depends on the values of terms of order zero in the ordinary differential equations (ODEs), and it is easy to find for which values of these terms a given point in phase space is steady. Models can be synthesised first at the level of the circuits involved in the Jacobian matrix (that determines which types and numbers of steady states are consistent with the model), then only at the level of terms of order zero in the ODE's (that determines which of the steady states actually exist), hence the title 'Circular casuality'.
Weld Joint Defect Analysis of Friction Stir Welding of Polypropylene Plastic Plate%聚丙烯塑料板搅拌摩擦焊接头缺陷分析
Institute of Scientific and Technical Information of China (English)
党杰; 张琳
2014-01-01
搅拌摩擦焊具有高效、节能、无污染等优点，既能焊接铝合金等低熔点材料，也能焊接聚丙烯塑料板材。各种工艺参数合理匹配时，焊缝美观，质量良好。但是，工艺参数选择不当时，焊缝会存在明显缺陷。本文分析了用搅拌摩擦焊焊接聚丙烯塑料板时所出现的飞边、孔洞等缺陷。%Friction stir welding have more advantages as high effectiveness, energy saving and environmental friendly. It not only can weld low melting point materials such as aluminum alloy but also weld polypropylene ( PP) plastic plate. The appropriate welding parameters can make the quality reliable and the weld joint forms well. But, the weld joint may have exists defect when welding parameter choice unsuitable. This paper analyzes the defects such as flash and holes when using friction stir welding for PP plastic plate.
Pocket gauge for checking insert clocking of multipin circular connectors
Billmeyer, E.
1974-01-01
Prototype gauge has been constructed of heavy clear plastic with engraved degree lines, numerals, and alignment lines. With suitable modification, gauge can be mass produced. It could be marketed directly to users or to manufacturers of circular multipin connectors.
Origami - Folded Plate Structures
Buri, Hans Ulrich
2010-01-01
This research investigates new methods of designing folded plate structures that can be built with cross-laminated timber panels. Folded plate structures are attractive to both architects and engineers for their structural, spatial, and plastic qualities. Thin surfaces can be stiffened by a series of folds, and thus not only cover space, but also act as load bearing elements. The variation of light and shadow along the folded faces emphasizes the plas...
Diffraction of Electromagnetic Wave by Circular Disk and Circular Hole
Shahzad, Muhammad Adnan
2010-01-01
The problem of diffraction of an electromagnetic plane wave by a perfectly conducting circular disk and its complementary problem, diffraction by a circular hole in an infinite conducting plate, are rigorously solved using the method of the Kobayashi potential. The mathematical formulation involved dual integral equation derived from the potential integral and boundary condition on the plane where a disk or hole is located. The weighting function in the potential integral are determined by applying the properties of the Weber-Schafheitlin's discontinuous integral and the solution are obtained in the form of a matrix equation. The matrix elements of the equations for the expansion coefficients are given by three kinds of infinite integral and the series solution for these infinite integral are derived. For the verification of these series solution, the numerical integral are derived and the results are computed numerically using the method of Gaussian quadrature for conformation. The numerical results are give...
Inflation of polymer melts into elliptic and circular cylinders
DEFF Research Database (Denmark)
Rasmussen, Henrik Koblitz; Christensen, Jens Horslund; Gøttsche, Søren
2000-01-01
A thin sheet (membrane) of the polymeric material is clamped between a Teflon-coated thermostated plate and a thermostated aluminium cylinder. By applying thermostated air through the plate, the polymer membrane deforms into an elliptic or a circular cylinder. The position of the top of the infla......A thin sheet (membrane) of the polymeric material is clamped between a Teflon-coated thermostated plate and a thermostated aluminium cylinder. By applying thermostated air through the plate, the polymer membrane deforms into an elliptic or a circular cylinder. The position of the top...
... Surgery? A Week of Healthy Breakfasts Shyness Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A A ... forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word "plastic" ...
Energy Technology Data Exchange (ETDEWEB)
Corona, Edmundo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gullerud, Arne S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Haulenbeek, Kimberly K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Reu, Phillip L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-06-01
The work presented in this report concerns the response and failure of thin 2024- T3 aluminum alloy circular plates to a blast load produced by the detonation of a nearby spherical charge. The plates were fully clamped around the circumference and the explosive charge was located centrally with respect to the plate. The principal objective was to conduct a numerical model validation study by comparing the results of predictions to experimental measurements of plate deformation and failure for charges with masses in the vicinity of the threshold between no tearing and tearing of the plates. Stereo digital image correlation data was acquired for all tests to measure the deflection and strains in the plates. The size of the virtual strain gage in the measurements, however, was relatively large, so the strain measurements have to be interpreted accordingly as lower bounds of the actual strains in the plate and of the severity of the strain gradients. A fully coupled interaction model between the blast and the deflection of the structure was considered. The results of the validation exercise indicated that the model predicted the deflection of the plates reasonably accurately as well as the distribution of strain on the plate. The estimation of the threshold charge based on a critical value of equivalent plastic strain measured in a bulge test, however, was not accurate. This in spite of efforts to determine the failure strain of the aluminum sheet under biaxial stress conditions. Further work is needed to be able to predict plate tearing with some degree of confidence. Given the current technology, at least one test under the actual blast conditions where the plate tears is needed to calibrate the value of equivalent plastic strain when failure occurs in the numerical model. Once that has been determined, the question of the explosive mass value at the threshold could be addressed with more confidence.
Macquart, JP
2002-01-01
We discuss the constraints that recent observations place on circular polarisation in AGN. In many sources the circular polarisation is variable on short timescales, indicating that it originates in compact regions of the sources. The best prospects for gleaning further information about circular po
Kahn, Bernd; Wang, Zuoyuan; Sensistaffar, Edwin
1984-01-01
The fraction of alpha-particle tracks due to radioactivity plated out on its surface was measured for CR-39 nuclear track detector foils used to determine working level values in air. Bare foils were exposed to known concentrations of airborne 222Rn and its short-lived daughters in a calibration chamber. The amounts of 218Po and 214Po on the foil surface were measured with a calibrated diffused junction detector-spectrometer system immediately after the foils were removed from the chamber. Deposition was mostly by 218Po, with some 214Pb but essentially no 214Bi. The track density due to the plated-out radionuclides and the 222Rn, 218Po, and 214Po in chamber air was calculated and compared to the value measured by electrochemical etching. The calculated values generally were slightly above the measured values. On the basis of these calculations, the deposited radioactivity contributed slightly less than one-half of the total tracks in one test and slightly more than two-thirds in another. This effect complicates calibration of the detector relative to airborne radon daughters.
Institute of Scientific and Technical Information of China (English)
陈德胜; 杨冬平; 蔡艳青; 龙凤乐; 牛更奇; 邵永波
2014-01-01
环口板加固管节点是一种比较新颖的加固方法，施工方便快捷而且加固效果显著。运用有限元方法对平面内弯矩作用下的环口板加固 T 型圆钢管节点的极限承载力进行了研究。对环口板加固 T 型圆钢管节点的面内弯曲承载力进行了参数分析，参数包括支管直径与主管直径比β，主管直径与2倍主管壁厚的比γ，环口板厚度与主管管壁厚之比τc 和环口板长度与支管直径之比 lc/d1等计算。结果表明，采用适当尺寸的环口板加固后的 T 型管节点的承载力相对于未加固 T 型管节点的承载力得到显著提高。改变环口板的厚度相对于改变环口板的长度对静力强度的提高更有效。最后，在参数分析的基础上提出了环口板加强型 T 型圆钢管节点在平面内弯矩作用下的承载力计算公式。%Collar plate reinforcement is a new method for reinforcing tubular joints, and it is of fast fabrication and effective. Finite element method is used to investigate the static strength of collar plate reinforced circular hollow section (CHS) T-joints subjected to in-plane bending load. A study is conducted to analyze the effect of geometrical parameters, i.e. brace-to-chord diameter ratio β, collar-plate to chord wall thickness ratio τc, and collar-plate length to brace diameter ratio lc/d1, on the static strength of tubular T-joints. It is found that significant strength enhancement can be achieved for a collar plate reinforced tubular joint through suitable size design comparing with the un-reinforced one. Compared to the length of the collar plate, the thicknesses of the collar plate is more effective for improving the static strength of the T-joints. Finally, a parametric equation for predicting the load bearing capacity of circular tubular T-joints with collar plate reinforcement subjected to in-plane bending load is presented.
Publication of administrative circular
HR Department
2009-01-01
ADMINISTRATIVE CIRCULAR NO. 23 (REV. 2) – SPECIAL WORKING HOURS Administrative Circular No. 23 (Rev. 2) entitled "Special working hours", approved following discussion in the Standing Concertation Committee on 9 December 2008, will be available on the intranet site of the Human Resources Department as from 19 December 2008: http://cern.ch/hr-docs/admincirc/admincirc.asp It cancels and replaces Administrative Circular No. 23 (Rev. 1) entitled "Stand-by duty" of April 1988. A "Frequently Asked Questions" information document on special working hours will also be available on this site. Paper copies of this circular will shortly be available in Departmental Secretariats. Human Resources Department Tel. 78003
PUBLICATION OF ADMINISTRATIVE CIRCULAR
HR Department
2008-01-01
ADMINISTRATIVE CIRCULAR NO. 23 (REV. 2) – SPECIAL WORKING HOURS Administrative Circular No. 23 (Rev. 2) entitled "Special working hours", approved following discussion in the Standing Concertation Committee meeting of 9 December 2008, will be available on the intranet site of the Human Resources Department as from 19 December 2008: http://cern.ch/hr-docs/admincirc/admincirc.asp It cancels and replaces Administrative Circular No. 23 (Rev. 1) entitled "Stand-by duty" of April 1988. A "Frequently Asked Questions" information document on special working hours will also be available on this site. Paper copies of this circular will shortly be available in departmental secretariats. Human Resources Department Tel. 78003
Strong Trinucleotide Circular Codes
Directory of Open Access Journals (Sweden)
Christian J. Michel
2011-01-01
Full Text Available Recently, we identified a hierarchy relation between trinucleotide comma-free codes and trinucleotide circular codes (see our previous works. Here, we extend our hierarchy with two new classes of codes, called DLD and LDL codes, which are stronger than the comma-free codes. We also prove that no circular code with 20 trinucleotides is a DLD code and that a circular code with 20 trinucleotides is comma-free if and only if it is a LDL code. Finally, we point out the possible role of the symmetric group ∑4 in the mathematical study of trinucleotide circular codes.
Lubliner, Jacob
2008-01-01
The aim of Plasticity Theory is to provide a comprehensive introduction to the contemporary state of knowledge in basic plasticity theory and to its applications. It treats several areas not commonly found between the covers of a single book: the physics of plasticity, constitutive theory, dynamic plasticity, large-deformation plasticity, and numerical methods, in addition to a representative survey of problems treated by classical methods, such as elastic-plastic problems, plane plastic flow, and limit analysis; the problem discussed come from areas of interest to mechanical, structural, and
Analytical Optimization of Piezoelectric Circular Diaphragm Generator
Directory of Open Access Journals (Sweden)
S. Mohammadi
2013-01-01
Full Text Available This paper presents an analytical study of the piezoelectric circular diaphragm microgenerator using strain energy method. Piezoelectrics are the intelligent materials that can be used as transducer to convert mechanical energy into electrical energy and vice versa. The aim of this paper is to optimize produced electrical energy from mechanical pressure. Therefore, the circular metal plate equipped with piezoelectric circular patch has been considered with simply and clamped supports. A comprehensive modeling, parametrical study and the effect of the boundary conditions on the performance of the microgenerator have been investigated. The system is under variable pressure from an oscillating pressure source. Results are presented for PZT and PMN-PT piezoelectric materials with steel and aluminum substrates. An optimal value for the radius and thickness of the piezoelectric layer with a special support condition has been obtained.
UNSYMMETRICAL LARGE DEFORMATION PROBLEM OF ORTHOTROPIC PLATES
Institute of Scientific and Technical Information of China (English)
王新志; 赵永刚; 叶开沅; 黄达文
2002-01-01
Based upon the theory of anisotropic plates, the unsymmetrical large deformation equations of orthotropic circular plates were derived. By using Fourier series, the partial differential equations of this problem can be transformed into sets of nonlinear differential equations. And the procedure to solve the problem using the iterative method is given.
Micromachined silicon plates for sensing molecular interactions
Carlen, E.T.; Weinberg, M.S.; Dube, C.E.; Zapata, A.M.; Borenstein, J.T.
2006-01-01
A micromachined surface stress sensor based on a thin suspended crystalline silicon circular plate measures differential surface stress changes associated with vapor phase chemisorption of an alkanethiol self-assembled monolayer. The isolated face of the suspended silicon plate serves as the sensing
Circularity and Lambda Abstraction
DEFF Research Database (Denmark)
Danvy, Olivier; Thiemann, Peter; Zerny, Ian
2013-01-01
circular unknowns as dead variables, and we apply the functions to them. The result is a lazy circular program a la Bird. We illustrate the two transformations by mapping an algebraic construct to an isomorphic one with new leaves, reading a binary number as sug- gested by Knuth, and backpatching...
Perfect Circular Dichroic Metamirrors
Wang, Zuojia; Liu, Yongmin
2015-01-01
In nature, the beetle Chrysina gloriosa derives its iridescence by selectively reflecting left-handed circularly polarized light only. Here, for the first time, we introduce and demonstrate the optical analogue based on an ultrathin metamaterial, which we term circular dichroic metamirror. A general method to design the circular dichroic metasmirror is presented under the framework of Jones calculus. It is analytically shown that the metamirror can be realized by two layers of anisotropic metamaterial structures, in order to satisfy the required simultaneous breakings of n-fold rotational (n>2) and mirror symmetries. We design an infrared metamirror, which shows perfect reflectance for left-handed circularly polarized light without reversing its handedness, while almost completely absorbs right-handed circularly polarized light. These findings offer new methodology to realize novel chiral optical devices for a variety of applications, including polarimetric imaging, molecular spectroscopy, as well as quantum ...
Institute of Scientific and Technical Information of China (English)
邵永波; 岳永生; 蔡艳青
2011-01-01
Collar plate reinforcement is a new reinforcing method for tubular joints, and it is of fast fabrication and effective. To carry out further study on the behaviour of tubular joints after reinforced with collar plate, the hysteretic behaviour of 4 full-scale un-reinforced tubular T-joints and 4 corresponding T-joint specimens reinfoced with collar plate under quasi-static axial cyclic loading is investigated experimentally. Based on the experimental results, it is found that both the static strength and the ductility are increased for the reinforced specimen, and thus the reinforced T-joint can dissipate more energy caused by seismic actions. It is also found from the experimental phenomenon that the failure position is located at the comer of the collar plate, which is much different from the un-reinforced specimen for which the failure position is located at the weld toe along the brace/chord intersection.%环口板加固管节点是一种比较新颖的加固方法，该方法施工方便快捷而且加固效果显著。为了进一步研究环口板加固后管节点的性能特点，分别对4个足尺度未加固T型圆钢管节点和4个对应的采用环口板加固的足尺度T节点试件进行了轴向反复荷载作用下的拟静力滞回性能研究。基于试验测试结果，发现加固后的管节点在提高静力承载力的同时，其延性指标也有所提高，从而耗能性能更好，利于抗震。根据试验现象发现：采用环口板加固的T节点，可以将破坏发生的部位由原来未加固节点的焊趾处转移到环口板与主管表面焊缝连接的端角上，改变了管节点的破坏模式。
Elastic-plastic behavior of a semicircular frame being pressed against a rigid plane
Institute of Scientific and Technical Information of China (English)
X. W. Zhang; J. L. Yang; T. X. Yu
2008-01-01
As a simplified structural model, a semicircular frame is used to study the crashworthiness behavior of an aircraft fuselage. The quasi-static large elastic-plastic deformation of a semicircular frame in the process of its being pressed against a rigid ground is analyzed. First, based on the linear elastic assumption, the quasi-static large deformation contact process of the frame can be divided into three phases, i.e., point contact, line contact and post-buckling. By means of a shooting method, the relations between the displacement and contact force as well as the distribution of bending moment in the three phases are obtained. Then, by assuming an elastic, perfectly-plastic moment-curvature relationship for the semi-circular frame, the contact process is analyzed in detail to reveal the plastic collapse mechanism, the traveling of plastic hinge and the force-displacement relationship. In order to verify the analysis, a preliminary experiment was conducted, in which two types of half rings with clamped ends were pressed by a rigid plate. In addition, a numerical simulation is also conducted by employing ABAQUS to analyze both rectangular cross-sectional beam and I-beam. Finally, the theoretical predictions are compared with the experimental results and numerical solutions, showing that the elastic-plastic analysis can predict the contact process very well.
21 CFR 866.4800 - Radial immunodiffusion plate.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radial immunodiffusion plate. 866.4800 Section 866....4800 Radial immunodiffusion plate. (a) Identification. A radial immunodiffusion plate for clinical use is a device that consists of a plastic plate to which agar gel containing antiserum is added. In...
Kämper, Jan-Hinrich; Nöllenburg, Martin
2011-01-01
We present a new circular-arc cartogram model in which countries are drawn with circular arcs instead of straight-line segments. Given a geographic map and values associated with each country in the map, the cartogram is a new map in which the areas of the countries represent the corresponding values. In the circular-arc cartogram model straight-line segments can be replaced with circular arcs in order to achieve the desired areas, while the corners of the polygons defining each country remain fixed. The countries in circular-arc cartograms have the aesthetically pleasing appearance of clouds or snowflakes, depending on whether their edges are bent outwards or inwards. This makes is easy to determine whether a country has grown or shrunk, just by its overall shape. We show that determining whether a given map and area-values can be realized with a circular-arc cartogram is an NP-hard problem. Next we describe a heuristic method for constructing circular-arc cartograms, which uses a max-flow computation on the...
Pewsey, Arthur; Ruxton, Graeme D
2013-01-01
Circular Statistics in R provides the most comprehensive guide to the analysis of circular data in over a decade. Circular data arise in many scientific contexts whether it be angular directions such as: observed compass directions of departure of radio-collared migratory birds from a release point; bond angles measured in different molecules; wind directions at different times of year at a wind farm; direction of stress-fractures in concretebridge supports; longitudes of earthquake epicentres or seasonal and daily activity patterns, for example: data on the times of day at which animals are c
DEFF Research Database (Denmark)
Merrild, Heidi; Guldager Jensen, Kasper; Sommer, John
2016-01-01
of the circular strategies is not only in the future. Increased flexibility, optimized operation and maintenance, as well as a healthier building, is low-hanging fruit that can be harvested today. The project’s principles can be implemented in industrialized construction in a large scale today. That is proven......Natural resources are scarce and construction accounts for 40 percent of the material and energy consumption in Europe. This means that a switch to a circular future is necessary. ’Building a Circular Future’ maps out where we are, where we are going, and what is needed for this conversion to take...
Moseley, Christine
2000-01-01
Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)
Process designing for laser forming of circular sheet metal
Institute of Scientific and Technical Information of China (English)
Q. Nadeem; W. J. Seong; S. J. Na
2012-01-01
Laser forming is a new type of flexible manufacturing process that has become viable for the shaping of metallic components.Process designing of laser forming involves finding a set of process parameters,including laser power,laser scanning paths,and scanning speed,given a prescribed shape.To date,research has focused on process designing for rectangular plates,and only a few studies are presented for axis-symmetric geometries like circular plates.In the present study,process designing for axis-symmetric geometries-with focus on class of shapes--is handled using a formerly proposed distance-based approach.A prescribed shape is achieved for geometries such as quarter-circular and half-circular ring plates.Experimental results verify the applicability of the proposed method for a class of shapes.%Laser forming is a new type of flexible manufacturing process that has become viable for the shaping of metallic components. Process designing of laser forming involves finding a set of process parameters, including laser power, laser scanning paths, and scanning speed, given a prescribed shape. To date, research has focused on process designing for rectangular plates, and only a few studies are presented for axis-symmetric geometries like circular plates. In the present study, process designing for axis-symmetric geometries-with focus on class of shapes-is handled using a formerly proposed distance-based approach. A prescribed shape is achieved for geometries such as quarter-circular and half-circular ring plates. Experimental results verify the applicability of the proposed method for a class of shapes.
Administrative & Operational Circulars - Reminder
HR Department
2011-01-01
All Administrative and Operational Circulars are available on the intranet site of the Human Resources Department at the following address: http://cern.ch/hr-docs/admincirc/admincirc.asp Department Head Office
Experimental evidence for formation mechanism of regular circular fringes
Wang, Y.; Zhu, R.; Wang, G.; Wang, P.; Li, H.; Zhang, W.; Ren, G.
2016-10-01
Laser active suppressing jamming is one of the most effective technologies to cope with optoelectric imaging systems. In the process of carrying out laser disturbing experiment, regular circular fringes often appeared on the detector, besides laser spot converging by optical system. First of all, the formation of circular fringes has been experimentally investigated by using a simple converging lens to replace the complex optical system. Moreover, circular fringes have been simulated based on the interference theory of coherent light. The coherence between the experimental phenomena and the simulated results showed that the formation mechanism of regular circular fringes was the interference effect between reflected light by back surface of lens and directly refractive light on the detector. At last, the visibility of circular fringes has been calculated from 0.05 to 0.22 according to the current plating standard of lens surface and manufacture technique of optoelectric detector.
Circular words and applications
Directory of Open Access Journals (Sweden)
Benoît Rittaud
2011-08-01
Full Text Available We define the notion of circular words, then consider on such words a constraint derived from the Fibonacci condition. We give several results on the structure of these circular words, then mention possible applications to various situations: periodic expansion of numbers in numeration systems, "gcd-property" of integer sequences, partition of the prefix of the fixed point of the Fibonacci substitution, spanning trees of a wheel. Eventually, we mention some open questions.
DEFF Research Database (Denmark)
Hansen, Lennard Højbjerg
2014-01-01
It has been an accepted precept in film theory that specific stylistic features do not express specific content. Nevertheless, it is possible to find many examples in the history of film in which stylistic features do express specific content: for instance, the circular camera movement is used...... such as the circular camera movement. Keywords: embodied perception, embodied style, explicit narration, interpretation, style pattern, television style...
Laser direct joining of metal and plastic
Energy Technology Data Exchange (ETDEWEB)
Katayama, Seiji [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Kawahito, Yousuke [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)], E-mail: kawahito@jwri.osaka-u.ac.jp
2008-12-15
We have developed an innovative rapid laser direct joining process of metal and plastic lap plates without adhesives or glues. The joints made between a Type 304 stainless steel plate and a polyethylene terephthalate (PET) plastic sheet of 30 mm width possessed tensile shear loads of about 3000 N. Transmission electron microscope photographs of the joint demonstrated that Type 304 and the PET were bonded on the atomic, molecular or nanostructural level through a Cr oxide film.
Unified characteristics line theory of spacial axisymmetric plastic problem
Institute of Scientific and Technical Information of China (English)
YU; Maohong; (
2001-01-01
Karman, Th., Zur theorie der spanungszustnde in plastischen und sandartigen medion, Nachr. Gesellsch. Wissensch., Gttingen, 1909.［17］Szczepinski, W., Introduction to the Mechanics of Plastic Forming of Metals, Netherlands: Sijthoff and Noordhoff, 1979.［18］Chen, W. F., Limit Analysis and Soil Plasticity, New York: Elsevier, 1975.［19］Yu, M. H., He, L. N., A new model and theory on yield and failure of materials under complex stress state, Mechanical Behaviors of Materials～6, Oxford: Pergamon Press, 1991, 3: 841—846.［20］Yu, M. H., New System of Strength Theory (in Chinese), Xi'an: Xi'an Jiaotong Universitry Press, 1992.［21］Yu, M. H., He, L. N., Song, L. Y., Twin shear stress theory and its generalization, Scientia Sinica (Science in China), Series A, 1985, 28(11): 1174—1183.［22］Yu, M. H., Yang, S. Y. et al., Unified elasto-plastic associated and non-associated constitutive model and its engineering applications, Computers and Structures, 1999, 71: 627—636.［23］Ma, G. W., Shoji, I., Plastic limit analysis of circular plates with respect to unified yield criterion, Int. J. Mech. Sci., 1998, 40(10): 963.［24］Ma, G. W., Hao, H., Unified plastic limit analyses of circular plates under arbitrary load, Journal of Applied Mechanics, ASME, 1999, 66(2): 568.［25］Qiang, H. F., Lu, N., Liu, B. J., Unified solutions of crack tip plastic zone under small scale yielding, Chinese Journal of Mechanical Engineering, (in Chinese with English abstract), 1999, 35(1): 34—38.［26］Yang, S. Y., Yu, M. H., Constitutive descriptions of multiphase poropus media, Acta Mechanica Sinica (in Chinese with English abstract), 2000, 32(1):11—24.［27］Yang, S. Y., Yu, M. H., An elasto-plastic damage model for saturated and unsaturated geomaterials, Acta Mechanica Sinica (in Chinese with English abstract), 2000, 32(2): 198—206.［28］Cheng, H. X., Li, J. J., Zhang, G. S. et al., Finite element analysis program system HAJIF(X), Chinese Journal of
Compact waveguide circular polarizer
Tantawi, Sami G.
2016-08-16
A multi-port waveguide is provided having a rectangular waveguide that includes a Y-shape structure with first top arm having a first rectangular waveguide port, a second top arm with second rectangular waveguide port, and a base arm with a third rectangular waveguide port for supporting a TE.sub.10 mode and a TE.sub.20 mode, where the end of the third rectangular waveguide port includes rounded edges that are parallel to a z-axis of the waveguide, a circular waveguide having a circular waveguide port for supporting a left hand and a right hand circular polarization TE.sub.11 mode and is coupled to a base arm broad wall, and a matching feature disposed on the base arm broad wall opposite of the circular waveguide for terminating the third rectangular waveguide port, where the first rectangular waveguide port, the second rectangular waveguide port and the circular waveguide port are capable of supporting 4-modes of operation.
Tailoring the Electromagnetic Near Field with Patterned Surfaces: Near-Field Plates
2014-12-10
near-field plates possible. A linear near-field plate is shown in Fig. 1, which can create a subwavelength line (1D) focus when excited by an...concentric annular slots on a circular grounded dielectric slab. The plate is excited through a coaxial cable and its rim is short circuited. The slots are...standard printed circuit board technology. The plates consist of concentric annular slots on a circular grounded dielectric slab excited through a coaxial
Chladni's law for vibrating plates
Rossing, Thomas D.
1982-03-01
The normal vibrational modes of free circular plates can be classified according to the number of nodal diameters m and the number of nodal circles n. Chladni observed that the addition of one nodal circle raised the frequency f about the same amount as adding two nodal diameters, and Rayleigh pointed out that f is proportional to (m+2n)2 for large f. Waller, however, concluded that the number of nodal diameters necessary to raise the frequency as much as a nodal circle varies from two to five. We have examined data on the vibrations of flat and non-flat circular plates and fitted their vibration frequencies to the relationship f = c(m+bn)k. By proper choice of c it is possible to satisfy Chladni's law (b = 2, k = 2) over quite a wide range of frequency in flat plates. Non-flat plates such as cymbals and bells, require different choices of b and k. A brief history of Chladni patterns, and suggestions for observing and demonstrating the vibrational modes of plates are included (AIP).
Gao, Nan; Zhang, Yuchao; Xie, Changqing
2011-11-01
We introduce circular Fibonacci gratings (CFGs) that combine the concept of circular gratings and Fibonacci structures. Theoretical analysis shows that the diffraction pattern of CFGs is composed of fractal distributions of impulse rings. Numerical simulations are performed with two-dimensional fast Fourier transform to reveal the fractal behavior of the diffraction rings. Experimental results are also presented and agree well with the numerical results. The fractal nature of the diffraction field should be of great theoretical interest, and shows potential to be further developed into practical applications, such as in laser measurement with wideband illumination.
The Nonlinear Instability Modes of Dished Shallow Shells under Circular Line Loads
Liu Chang-Jiang; Zheng Zhou-Lian; Huang Cong-Bing; He Xiao-Ting; Sun Jun-Yi; Chen Shan-Lin
2011-01-01
This paper investigated the nonlinear stability problem of dished shallow shells under circular line loads. We derived the dimensionless governing differential equations of dished shallow shell under circular line loads according to the nonlinear theory of plates and shells and solved the governing differential equations by combing the free-parameter perturbation method (FPPM) with spline function method (SFM) to analyze the nonlinear instability modes of dished shallow shell under circular l...
Cooling simulation of plastic injection molding
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Analyses the cooling of mold and plastic part during injectionmolding and the continued cooling of plastic part after being ejected from mold using the heat transfer theory and Boundary Element Method (BEM) to predict the temperature distribution in both mold and plastic part,and presents the experiments carried out with plates of ABS (Acrylonitrile-Butadiene-Styrene) to verify the validity of the cooling analysis software used to simulate the temperature distribution in ABS plate parts, and concludes that the analysis software agree qualitatively well with actual experimental findings.
Barker, Tommy G.
This curriculum guide is designed to assist junior high schools industrial arts teachers in planning new courses and revising existing courses in plastics technology. Addressed in the individual units of the guide are the following topics: introduction to production technology; history and development of plastics; safety; youth leadership,…
Prins, M.; Mohammadi, S.; Slob, N.
2015-01-01
Recently the Circular Economy (CE) concept has gained momentum in the Netherlands, propounding that environmental impact reduction can provide a significant positive economical impulse. The government, larger parts of the industry as a whole, as well as the construction industry, has warmly received
Bordenave, Charles
2011-01-01
These expository notes are centered around the circular law theorem, which states that the empirical spectral distribution of a n \\times n random matrix with i.i.d. entries of variance 1/n tends to the uniform law on the unit disc of the complex plane as the dimension n tends to infinity. This phenomenon is the non-Hermitian counterpart of the semi circular limit for Wigner random Hermitian matrices, and the quarter circular limit for Marchenko-Pastur random covariance matrices. We present a proof in a Gaussian case, due to Silverstein, based on a formula by Ginibre, and a proof of the universal case by revisiting the approach of Tao and Vu, based on the Hermitization of Girko, the logarithmic potential, and the control of the small singular values. Beyond the finite variance model, we also consider the case where the entries have heavy tails, by using the objective method of Aldous and Steele borrowed from randomized combinatorial optimization. The limiting law is then no longer the circular law and is relat...
Prins, M.; Mohammadi, S.; Slob, N.
2015-01-01
Recently the Circular Economy (CE) concept has gained momentum in the Netherlands, propounding that environmental impact reduction can provide a significant positive economical impulse. The government, larger parts of the industry as a whole, as well as the construction industry, has warmly received
Wiimote Experiments: Circular Motion
Kouh, Minjoon; Holz, Danielle; Kawam, Alae; Lamont, Mary
2013-01-01
The advent of new sensor technologies can provide new ways of exploring fundamental physics. In this paper, we show how a Wiimote, which is a handheld remote controller for the Nintendo Wii video game system with an accelerometer, can be used to study the dynamics of circular motion with a very simple setup such as an old record player or a…
Transposable elements and circular DNAs
Mourier, Tobias
2016-09-26
Circular DNAs are extra-chromosomal fragments that become circularized by genomic recombination events. We have recently shown that yeast LTR elements generate circular DNAs through recombination events between their flanking long terminal repeats (LTRs). Similarly, circular DNAs can be generated by recombination between LTRs residing at different genomic loci, in which case the circular DNA will contain the intervening sequence. In yeast, this can result in gene copy number variations when circles contain genes and origins of replication. Here, I speculate on the potential and implications of circular DNAs generated through recombination between human transposable elements.
High performance 3D printed electronics using electroless plated copper
Jin Rong Jian; Taeil Kim; Jae Sung Park; Jiacheng Wang; Woo Soo Kim
2017-01-01
This paper presents design and performance validation of 3D printed electronic components, 3D toroidal air-core inductors, fabricated by multi-material based Fused Deposition Modelling (FDM) 3D printing technology and electroless copper plating. Designs of toroidal inductor is investigated with different core shapes and winding numbers; circular and half-circular cores with 10 and 13 turns of windings...
Directory of Open Access Journals (Sweden)
Xiwang Cui
2016-11-01
Full Text Available Leak localization is essential for the safety and maintenance of storage vessels. This study proposes a novel circular acoustic emission sensor array to realize the continuous CO2 leak localization from a circular hole on the surface of a large storage vessel in a carbon capture and storage system. Advantages of the proposed array are analyzed and compared with the common sparse arrays. Experiments were carried out on a laboratory-scale stainless steel plate and leak signals were obtained from a circular hole in the center of this flat-surface structure. In order to reduce the influence of the ambient noise and dispersion of the acoustic wave on the localization accuracy, ensemble empirical mode decomposition is deployed to extract the useful leak signal. The time differences between the signals from the adjacent sensors in the array are calculated through correlation signal processing before estimating the corresponding distance differences between the sensors. A hyperbolic positioning algorithm is used to identify the location of the circular leak hole. Results show that the circular sensor array has very good directivity toward the circular leak hole. Furthermore, an optimized method is proposed by changing the position of the circular sensor array on the flat-surface structure or adding another circular sensor array to identify the direction of the circular leak hole. Experiential results obtained on a 100 cm × 100 cm stainless steel plate demonstrate that the full-scale error in the leak localization is within 0.6%.
Institute of Scientific and Technical Information of China (English)
匡家寿
2015-01-01
目的：探讨半环形外固定支架加解剖钢板治疗胫骨远端开放性粉碎性骨折(DTOCF)合并腓骨骨折的应用价值。方法38例确诊治疗的DTOCF合并腓骨远端骨折患者，依据随机分配原则分为解剖组和对照组，各19例。对照组给予常规胫骨远端骨折单臂外固定支架腓骨远端重建钢板内固定手术治疗，解剖组给予胫骨远端半环形外固定支架及腓骨解剖钢板治疗，采用Baird-Jackson踝关节评分(BJAS)评估疗效并随访1年，统计分析所有患者骨折愈合时间、手术时间、出血量、疗效和并发症。结果解剖组骨折愈合时间、手术时间、出血量明显低于对照组，差异有统计学意义(P<0.05)；解剖组患者治疗优良率为94.74%，对照组患者治疗优良率为78.95%，前者明显高于后者，差异有统计学意义(P<0.05)；解剖组患者并发症发生率为10.53%，对照组患者并发症发生率为26.32%，前者明显低于后者，差异有统计学意义(P<0.05)。结论胫骨远端骨折半环形外固定支架及腓骨远端骨折解剖钢板治疗，可有效提高DTOCF合并腓骨远端骨折的疗效，降低并发症发生，值得临床作进一步推广。%Objective To investigate the application value of half circular external fixation stand and anatomical plate in the treatment of distal tibia open comminuted fracture (DTOCF) complicated with distal fibula fracture.Methods A total of 38 patients of diagnosed DTOCF complicated with distal fibula fracture were randomly divided into anatomy group and control group, with 19 cases in each group. The control group received conventional surgery by one-arm fixation support for distal tibia fracture and reconstruction plate fixation for distal fibula fracture. The anatomy group received half circular external fixation stand for distal tibia fracture and anatomical plate for distal fibula fracture. Baird-Jackson ankle score (BJAS) was applied for evaluation
Kappa Coefficients for Circular Classifications
Warrens, Matthijs J.; Pratiwi, Bunga C.
2016-01-01
Circular classifications are classification scales with categories that exhibit a certain periodicity. Since linear scales have endpoints, the standard weighted kappas used for linear scales are not appropriate for analyzing agreement between two circular classifications. A family of kappa coefficie
Precision Plate Plan View Pattern Predictive Model
Institute of Scientific and Technical Information of China (English)
ZHAO Yang; YANG Quan; HE An-rui; WANG Xiao-chen; ZHANG Yun
2011-01-01
According to the rolling features of plate mill, a 3D elastic-plastic FEM （finite element model） based on full restart method of ANSYS/LS-DYNA was established to study the inhomogeneous plastic deformation of multipass plate rolling. By analyzing the simulation results, the difference of head and tail ends predictive models was found and modified. According to the numerical simulation results of 120 different kinds of conditions, precision plate plan view pattern predictive model was established. Based on these models, the sizing MAS （mizushima automatic plan view pattern control system） method was designed and used on a 2 800 mm plate mill. Comparing the rolled plates with and without PVPP （plan view pattern predictive） model, the reduced width deviation indicates that the olate !olan view Dattern predictive model is preeise.
Efficient circular thresholding.
Lai, Yu-Kun; Rosin, Paul L
2014-03-01
Otsu's algorithm for thresholding images is widely used, and the computational complexity of determining the threshold from the histogram is O(N) where N is the number of histogram bins. When the algorithm is adapted to circular rather than linear histograms then two thresholds are required for binary thresholding. We show that, surprisingly, it is still possible to determine the optimal threshold in O(N) time. The efficient optimal algorithm is over 300 times faster than traditional approaches for typical histograms and is thus particularly suitable for real-time applications. We further demonstrate the usefulness of circular thresholding using the adapted Otsu criterion for various applications, including analysis of optical flow data, indoor/outdoor image classification, and non-photorealistic rendering. In particular, by combining circular Otsu feature with other colour/texture features, a 96.9% correct rate is obtained for indoor/outdoor classification on the well known IITM-SCID2 data set, outperforming the state-of-the-art result by 4.3%.
Bo, Pengbo
2011-07-01
The most important guiding principle in computational methods for freeform architecture is the balance between cost efficiency on the one hand, and adherence to the design intent on the other. Key issues are the simplicity of supporting and connecting elements as well as repetition of costly parts. This paper proposes so-called circular arc structures as a means to faithfully realize freeform designs without giving up smooth appearance. In contrast to non-smooth meshes with straight edges where geometric complexity is concentrated in the nodes, we stay with smooth surfaces and rather distribute complexity in a uniform way by allowing edges in the shape of circular arcs. We are able to achieve the simplest possible shape of nodes without interfering with known panel optimization algorithms. We study remarkable special cases of circular arc structures which possess simple supporting elements or repetitive edges, we present the first global approximation method for principal patches, and we show an extension to volumetric structures for truly threedimensional designs. © 2011 ACM.
National Research Council Canada - National Science Library
Singhi, Anil Kumar; Vinoth, Bharathi; Kuruvilla, Sarah; Sivakumar, Kothandam
2015-01-01
Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics...
Trettnak, Wolfgang
2015-01-01
In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. The slideshow below gives you a taste of the artworks by Wolfgang Trettnak and Margarita Cimadevila.
Institute of Scientific and Technical Information of China (English)
履之
1994-01-01
Already ubiquitous in homes and cars, plastic is now appearing inbridges. An academic-industrial consortium based at the University ofCalifornia in San Diego is launching a three-year research program aimed atdeveloping the world’s first plastic highway bridge, a 450-foot span madeentirely from glass-,carbon,and polymer-fiber-reinforced composite mate-rials, the stuff of military aircraft. It will cross Interstate 5 to connect thetwo sides of the school’s campus.
Institute of Scientific and Technical Information of China (English)
阿布都瓦依提·玉苏甫; 王建华; 阿不都拉·艾尼瓦尔
2012-01-01
采用旋转圆板型陶瓷膜过滤器对5％的O/W(油/水)乳浊液进行了精密平衡过滤.过滤压力为50,100,150 kPa和圆板旋转速度为125,250,500 r/min时,对过滤速度和过滤量的影响进行了对比分析.结果表明,转速为250 r/min,压力为50 kPa时,达到过滤平衡的时间最短且运行稳定,过滤速度较高过滤量较大,在此条件下过滤效果较为理想.%The 5% 0/W (oil/water) emulsion was accurately filtrated by the circular plate with ceramic membrane filter. When the filter pressure was 50 kPa,100 kPa and 150 kPa and the speed of rotation was 125 r/min, 250 r/min and 500 r/min, it could compare and analyse the influnce of filtration speeds and a-mount of filtration. The result inJicated that when the speed of rotation was 250 r/min and filter pressure was 50 kPa?the time of reaching to filtration balance was the shortest and it was stable. The higher the filtration rate was,the larger the amount of filtration was. Therefore,the optimal condition was the speed of rotation 250 r/min and filter pressure 50 kPa for the filtration of 5% O/W (oil/water) emulsion.
GREEN PLASTIC: A NEW PLASTIC FOR PACKAGING
Mr. Pankaj Kumar*, Sonia
2016-01-01
This paper gives a brief idea about a new type of plastic called as bio-plastic or green plastic. Plastic is used as a packaging material for various products, but this plastic is made up of non renewable raw materials. There are various disadvantages of using conventional plastic like littering, CO2 production, non-degradable in nature etc. To overcome these problems a new type of plastic is discovered called bio-plastic or green plastic. Bio-plastic is made from renewable resources and also...
A Novel Offset Fresnel Zone Plate Antenna
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
A novel offset Fresnel Zone Plate reflector Antenna (FZPA) is proposed, the phase correcting zone of this FZPA is elliptic. Based on Physical Optics Method, the focusing characteristics of the reflector are analyzed. The comparison of this new FZPA with the circular FZPA and Mawzones FZPA is made.
Advances and Trends in Plate Buckling Research.
1982-12-01
Hydrostatic State of In- Plane Stress. Instituto de Mecanica Aplicada No. 79-21 (Puerto Belgrano, Argentina), June 1979, 10 pp. (to be published). 38. Leissa...and Elastic Stability of Circular Plates With Thickness Varying in a Bilinear Fashion. Instituto de Mecanica Aplicada No. 81-23 (Puerto Belgrano
Plate forming and break down pizza box
Pantisano, Frank; Devine, Scott M.
1992-01-01
A standard corrugated paper pizza box is provided with slit cuts cut through the top panel of the pizza box in a shape to form four circular serving plates with a beveled raised edge and cross slit cuts through the bottom panel of the pizza box separating the box into four essentially equal portions for easy disposal.
Nonlinear Vibration of Circular Plate with Variable Thickness
Institute of Scientific and Technical Information of China (English)
1998-01-01
ＮｏｎｌｉｎｅａｒＶｉｂｒａｔｉｏｎｏｆＣｉｒｃｕｌａｒＰｌａｔｅｗｉｔｈＶａｒｉａｂｌｅＴｈｉｃｋｎｅｓＹｅＺｈｉｍｉｎｇ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉｅｄＭａｔｈｅｍａｔｉｃｓａｎｄＭｅｃｈａｎｉｃｓ）ＡｂｓｔｒａｃｔＴｈｉｓ...
Antennas on circular cylinders
DEFF Research Database (Denmark)
Knudsen, H. L.
1959-01-01
antenna in a circular cylinder. By a procedure similar to the one used by Silver and Saunders, expressions have been derived for the field radiated from an arbitrary surface current distribution on a cylinder surface coaxial with a perfectly conducting cylinder. The cases where the space between the two...... cylindrical surfaces have the sane characteristic constants and different constants are treated separately. Extensive numerical computations of the field radiated from the slot antennas described here are being carried out, but no numerical results are yet available...
Gao, Steven; Zhu, Fuguo
2013-01-01
This book presents a comprehensive insight into the design techniques for different types of CP antenna elements and arrays In this book, the authors address a broad range of topics on circularly polarized (CP) antennas. Firstly, it introduces to the reader basic principles, design techniques and characteristics of various types of CP antennas, such as CP patch antennas, CP helix antennas, quadrifilar helix antennas (QHA), printed quadrifilar helix antennas (PQHA), spiral antenna, CP slot antennas, CP dielectric resonator antennas, loop antennas, crossed dipoles, monopoles and CP horns. Adva
1968-01-01
Only simple equipment, simple technology and low initial capital investment are needed in their manufacture. The condoms can be made by people who were previously unskilled or only semi-skilled workers. Plastic condoms differ from those made of latex rubber in that the nature of the plastic film allows unlimited shelf-life. Also, the plastic has a higher degree of lubricity than latex rubber; if there is a demand for extra lubrication in a particular market, this can be provided. Because the plastic is inert, these condoms need not be packaged in hermetically sealed containers. All these attributes make it possible to put these condoms on the distributors' shelves in developing countries competitively with rubber condoms. The shape of the plastic condom is based on that of the lamb caecum, which has long been used as luxury-type condom. The plastic condom is made from plastic film (ethylene ethyl acrilate) of 0.001 inch (0.0254 mm.) thickness. In addition, a rubber ring is provided and sealed into the base of the condom for retention during coitus. The advantage of the plastic condom design and the equipment on which it is made is that production can be carried out either in labour-intensive economy or with varying degrees of mechanization and automation. The uniform, finished condom if made using previously untrained workers. Training of workers can be done in a matter of hours on the two machines which are needed to produce and test the condoms. The plastic film is provided on a double wound roll, and condom blanks are prepared by means of a heat-sealing die on the stamping machine. The rubber rings are united to the condom blanks on an assembly machine, which consists of a mandrel and heat-sealing equipment to seal the rubber ring to the base of the condom. Built into the assembly machine is a simple air-testing apparatus that can detect the smallest pinhole flaw in a condom. The manufacturing process is completed by unravelling the condom from the assembly
Rubin, Bruce K
2016-09-01
Plastic bronchitis is an uncommon and probably underrecognized disorder, diagnosed by the expectoration or bronchoscopic removal of firm, cohesive, branching casts. It should not be confused with purulent mucous plugging of the airway as seen in patients with cystic fibrosis or bronchiectasis. Few medications have been shown to be effective and some are now recognized as potentially harmful. Current research directions in plastic bronchitis research include understanding the genetics of lymphatic development and maldevelopment, determining how abnormal lymphatic malformations contribute to cast formation, and developing new treatments. Copyright © 2016 Elsevier Inc. All rights reserved.
Mixed plastics recycling technology
Hegberg, Bruce
1995-01-01
Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.
Mixed boundary conditions for piezoelectric plates
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the plate.For the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate edge.They are then used for the correct formulation of boundary conditions for the interior solution.
Antonella Del Rosso
2015-01-01
In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...
Roggen, Marjolein
1998-01-01
De zonnecel van de toekomst is in de maak. Onderzoekers van uiteenlopend pluimage werken eendrachtig aan een plastic zonnecel. De basis is technisch gelegd met een optimale, door invallend licht veroorzaakte, vorming van ladingdragers binnen een composiet van polymeren en buckyballs. Nu is het zaak
DEFF Research Database (Denmark)
Merrild, Heidi; Guldager Jensen, Kasper; Sommer, John
2016-01-01
place. The construction industry is facing a major upheaval and must rethink both its business strategies and construction practice to be able to handle the new required market mechanisms and reap the rewards of the circular future. To facilitate this, there will be new companies with business...... strategies that do not yet exist, such as material exchanges, digital material managers and deconstruction experts. A Proven Positive Business Case Based on a specific 3XN project and existing construction practice at MT Højgaard, the project partners have developed and tested a business case based...... on the project’s strategies. The financial result is a profit of DKK 35 million on the structure alone in the demolition of a building built for the cost of DKK 860 million. The total potential for the whole building, calculated in projected material prices, is estimated to be up to 16% of the total construction...
Circularly Polarized MHOHG with Bichromatic Circularly Polarized Laser Pulses
Bandrauk, Andre D.; Mauger, Francois; Uzer, Turgay
2016-05-01
Circularly polarized MHOHG-Molecular High Order Harmonic Generation is shown to occur efficiently with intense ultrashort bichromatic circularly polarized pulses due to frequent electron-parent -ion recollision with co-or counter-rotating incident circular pulses as predicted in 1995. We show in this context that molecules offer a very robust and efficient frameworkfor the production of circularly polarized harmonics for the generation of single circularly polarized ``attosecond'' pulses. The efficiency of such new MHOHG is shown to depend on the compatibility of the symmetry of the molecular medium with the net electric field generated by the combination of the laser pulses.Using a time-dependent symmetry analysis with concrete examples such as H 2 + vs H 3 + we show how all the features(harmonic order and ∧ polarization) of MHOHG can be explained and predicted.
Operational circular No. 1 (Rev. 1) – Operational circulars
HR Department
2011-01-01
Operational Circular No. 1 (Rev. 1) is applicable to members of the personnel and other persons concerned. Operational Circular No. 1 (Rev. 1) entitled "Operational circulars", approved following discussion at the Standing Concertation Committee meeting on 4 May 2011, is available on the intranet site of the Human Resources Department: https://hr-docs.web.cern.ch/hr-docs/opcirc/opcirc.asp It cancels and replaces Operational Circular No. 1 entitled "Operational Circulars” of December 1996. This new version clarifies, in particular, that operational circulars do not necessarily arise from the Staff Rules and Regulations, and the functional titles have been updated to bring them into line with the current CERN organigram. Department Head Office
Solving the problem of elasticity for round thick plates at axially symmetric strain
Directory of Open Access Journals (Sweden)
Oleksiy Hvertsev
2016-12-01
Full Text Available An exact solution of the equations of elasticity for round plates loaded axially symmetric. The problem of bending round plates, which are under the influence of normal forces attached to any law to load any type of resistance. It is shown that pasture circular plate under axially symmetric load leads to appearance of temperature field.
... PSN PSEN GRAFT Contact Us News Plastic Surgery Statistics Plastic surgery procedural statistics from the American Society of Plastic Surgeons. Statistics by Year Print 2016 Plastic Surgery Statistics 2015 ...
Radial heat transfer behavior of impinging submerged circular jets
Energy Technology Data Exchange (ETDEWEB)
Zhou, D.W.; Ma, C.F. [Enhanced Heat Transfer and Energy Conservation, The Key Laboratory of Ministry of Education (China)
2006-05-15
Experiments were performed to investigate the radial heat transfer behaviors of impinging submerged circular jets. Local heat transfer rate at several fixed radial locations and different nozzle-to-plate spacings were correlated and compared. Results reveal that with the jet being far from the stagnation point, the coefficient in the correlation NuRe decreases while the exponent characterizing the flow pattern of the working liquid increases. (author)
Differential response to circularly polarized light by the jewel scarab beetle Chrysina gloriosa.
Brady, Parrish; Cummings, Molly
2010-05-01
Circularly polarized light is rare in the terrestrial environment, and cuticular reflections from scarab beetles are one of the few natural sources. Chrysina gloriosa LeConte 1854, a scarab beetle found in montane juniper forests of the extreme southwestern United States and northern Mexico, are camouflaged in juniper foliage; however, when viewed with right circularly polarizing filters, the beetles exhibit a stark black contrast. Given the polarization-specific changes in the appearance of C. gloriosa, we hypothesized that C. gloriosa can detect circularly polarized light. We tested for phototactic response and differential flight orientation of C. gloriosa toward different light stimuli. Chrysina gloriosa exhibited (a) positive phototaxis, (b) differential flight orientation between linear and circularly polarized light stimuli of equal intensities, and (c) discrimination between circularly polarized and unpolarized lights of different intensities consistent with a model of circular polarization sensitivity based on a quarter-wave plate. These results demonstrate that C. gloriosa beetles respond differentially to circularly polarized light. In contrast, Chrysina woodi Horn 1885, a close relative with reduced circularly polarized reflection, exhibited no phototactic discrimination between linear and circularly polarized light. Circularly polarized sensitivity may allow C. gloriosa to perceive and communicate with conspecifics that remain cryptic to predators, reducing indirect costs of communication.
Recycling of plastic waste: Screening for brominated flame retardants (BFRs)
DEFF Research Database (Denmark)
Pivnenko, Kostyantyn; Granby, Kit; Eriksson, Eva
2017-01-01
on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic......,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile...... flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling....
Circular chemiresistors for microchemical sensors
Ho, Clifford K.
2007-03-13
A circular chemiresistor for use in microchemical sensors. A pair of electrodes is fabricated on an electrically insulating substrate. The pattern of electrodes is arranged in a circle-filling geometry, such as a concentric, dual-track spiral design, or a circular interdigitated design. A drop of a chemically sensitive polymer (i.e., chemiresistive ink) is deposited on the insulating substrate on the electrodes, which spreads out into a thin, circular disk contacting the pair of electrodes. This circularly-shaped electrode geometry maximizes the contact area between the pair of electrodes and the polymer deposit, which provides a lower and more stable baseline resistance than with linear-trace designs. The circularly-shaped electrode pattern also serves to minimize batch-to-batch variations in the baseline resistance due to non-uniform distributions of conductive particles in the chemiresistive polymer film.
Directory of Open Access Journals (Sweden)
Anil Kumar Singhi
2015-01-01
Full Text Available Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics. They are ominous with poor prognosis. Sometimes, infection or airway reactivity may provoke cast bronchitis as a two-step insult on a vulnerable vascular bed. In such instances, aggressive management leads to longer survival. This report of cast bronchitis discusses its current understanding.
Full Text Available ... A A A Listen En Español Create Your Plate Create Your Plate is a simple and effective ... and that your options are endless. Create Your Plate! Click on the plate sections below to add ...
AUTHOR|(CDS)2108454; Zimmermann, Frank
2015-01-01
In response to a request from the 2013 Update of the European Strategy for Particle Physics, the global Future Circular Collider (FCC) study is preparing the foundation for a next-generation large-scale accelerator infrastructure in the heart of Europe. The FCC study focuses on the design of a 100-TeV hadron collider (FCC-hh), to be accommodated in a new ∼100 km tunnel near Geneva. It also includes the design of a high-luminosity electron-positron collider (FCC-ee), which could be installed in the same tunnel as a potential intermediate step, and a lepton-hadron collider option (FCC-he). The scope of the FCC study comprises accelerators, technology, infrastructure, detectors, physics, concepts for worldwide data services, international governance models, and implementation scenarios. Among the FCC core technologies figure 16-T dipole magnets, based on Nb3Sn superconductor, for the FCC-hh hadron collider, and a highly efficient superconducting radiofrequency system for the FCC-ee lepton collider. The interna...
Towards Future Circular Colliders
AUTHOR|(CDS)2108454; Zimmermann, Frank
2016-01-01
The Large Hadron Collider (LHC) at CERN presently provides proton-proton collisions at a centre-of-mass (c.m.) energy of 13 TeV. The LHC design was started more than 30 years ago, and its physics programme will extend through the second half of the 2030’s. The global Future Circular Collider (FCC) study is now preparing for a post-LHC project. The FCC study focuses on the design of a 100-TeV hadron collider (FCC-hh) in a new ∼100 km tunnel. It also includes the design of a high-luminosity electron-positron collider (FCC-ee) as a potential intermediate step, and a lepton-hadron collider option (FCC-he). The scope of the FCC study comprises accelerators, technology, infrastructure, detectors, physics, concepts for worldwide data services, international governance models, and implementation scenarios. Among the FCC core technologies figure 16-T dipole magnets, based on $Nb_3Sn$ superconductor, for the FCC-hh hadron collider, and a highly efficient superconducting radiofrequency system for the FCC-ee lepton c...
AUTHOR|(CDS)2108454; Zimmermann, Frank
2015-01-01
In response to a request from the 2013 Update of the European Strategy for Particle Physics, the global Future Circular Collider (FCC) study is preparing the foundation for a next-generation large-scale accelerator infrastructure in the heart of Europe. The FCC study focuses on the design of a 100-TeV hadron collider (FCC-hh), to be accommodated in a new ∼100 km tunnel near Geneva. It also includes the design of a high-luminosity electron-positron collider (FCC-ee), which could be installed in the same tunnel as a potential intermediate step, and a lepton-hadron collider option (FCC-he). The scope of the FCC study comprises accelerators, technology, infrastructure, detector, physics, concepts for worldwide data services, international governance models, and implementation scenarios. Among the FCC core technologies figure 16-T dipole magnets, based on Nb3Sn superconductor, for the FCC-hh hadron collider, and a highly efficient superconducting radiofrequency system for the FCC-ee lepton collider. The internat...
Continuum Mechanics of Beam and Plate Flexure
DEFF Research Database (Denmark)
Jönsson, Jeppe
This text has been written and used during the spring of 1995 for a course on flexural mechanics of beams and plates at Aalborg University. The idea has been to concentrate on basic principles of the theories, which are of importance to the modern structural engineer. Today's structural engineer...... must be acquainted with the classic beam and plate theories, when reading manuals and using modern software tools such as the finite element method. Each chapter includes supplementary theory and derivations enabling consultation of the notes also at a later stage of study. A preliminary chapter...... analysis of beam structures is presented and includes both upper and lower-bound solution techniques. The remaining chapters are devoted to plates. The classic elastic plate theories are presented. The plastic yield line theory for plates is presented including both upper and lower-bound techniques...
DEFF Research Database (Denmark)
Trnka, Hjalte; Rantanen, Jukka; Grohganz, Holger
2015-01-01
due to increasing amount of amorphous matter in the samples was observed in both vials and well plates. Cake collapse was found to be representative in well plates and could be effectively quantified using image analysis. Reconstitution time was also found to be equal in all three platforms. Finally......Abstract Context: Freeze-drying in presence of excipients is a common practice to stabilize biomacromolecular formulations. The composition of this formulation is known to affect the quality of the final product. Objective: The aim of this study was to evaluate freeze-drying in well-plates...... as a high throughput platform for formulation screening of freeze-dried products. Methods: Model formulations consisting of mannitol, sucrose and bovine serum albumin were freeze-dried in brass well plates, plastic well plates and vials. Physical properties investigated were solid form, residual moisture...
Digitalizing the Circular Economy
Reuter, Markus A.
2016-12-01
Metallurgy is a key enabler of a circular economy (CE), its digitalization is the metallurgical Internet of Things (m-IoT). In short: Metallurgy is at the heart of a CE, as metals all have strong intrinsic recycling potentials. Process metallurgy, as a key enabler for a CE, will help much to deliver its goals. The first-principles models of process engineering help quantify the resource efficiency (RE) of the CE system, connecting all stakeholders via digitalization. This provides well-argued and first-principles environmental information to empower a tax paying consumer society, policy, legislators, and environmentalists. It provides the details of capital expenditure and operational expenditure estimates. Through this path, the opportunities and limits of a CE, recycling, and its technology can be estimated. The true boundaries of sustainability can be determined in addition to the techno-economic evaluation of RE. The integration of metallurgical reactor technology and systems digitally, not only on one site but linking different sites globally via hardware, is the basis for describing CE systems as dynamic feedback control loops, i.e., the m-IoT. It is the linkage of the global carrier metallurgical processing system infrastructure that maximizes the recovery of all minor and technology elements in its associated refining metallurgical infrastructure. This will be illustrated through the following: (1) System optimization models for multimetal metallurgical processing. These map large-scale m-IoT systems linked to computer-aided design tools of the original equipment manufacturers and then establish a recycling index through the quantification of RE. (2) Reactor optimization and industrial system solutions to realize the "CE (within a) Corporation—CEC," realizing the CE of society. (3) Real-time measurement of ore and scrap properties in intelligent plant structures, linked to the modeling, simulation, and optimization of industrial extractive process
Towards future circular colliders
Benedikt, Michael; Zimmermann, Frank
2016-09-01
The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) presently provides proton-proton collisions at a center-of-mass (c.m.) energy of 13 TeV. The LHC design was started more than 30 years ago, and its physics program will extend through the second half of the 2030's. The global Future Circular Collider (FCC) study is now preparing for a post-LHC project. The FCC study focuses on the design of a 100-TeV hadron collider (FCC-hh) in a new ˜100 km tunnel. It also includes the design of a high-luminosity electron-positron collider (FCCee) as a potential intermediate step, and a lepton-hadron collider option (FCC-he). The scope of the FCC study comprises accelerators, technology, infrastructure, detectors, physics, concepts for worldwide data services, international governance models, and implementation scenarios. Among the FCC core technologies figure 16-T dipole magnets, based on Nb3 S n superconductor, for the FCC-hh hadron collider, and a highly-efficient superconducting radiofrequency system for the FCC-ee lepton collider. Following the FCC concept, the Institute of High Energy Physics (IHEP) in Beijing has initiated a parallel design study for an e + e - Higgs factory in China (CEPC), which is to be succeeded by a high-energy hadron collider (SPPC). At present a tunnel circumference of 54 km and a hadron collider c.m. energy of about 70 TeV are being considered. After a brief look at the LHC, this article reports the motivation and the present status of the FCC study, some of the primary design challenges and R&D subjects, as well as the emerging global collaboration.
Dowel Type Connections with Slotted-in Steel Plates
DEFF Research Database (Denmark)
Pedersen, Martin Bo Uhre; Clorius, Christian Odin; Damkilde, Lars;
1999-01-01
In the Eurocode the strength of dowel type connectors is determined according to the theory of plasticity. When the loading is in the grain direction the strength is well predicted by the plasticity theory. However, when the loading is in the transverse direction splitting may supervene plastic f...... failure, as is shown in test series on smaller specimens with slotted-in steel plates. The scope of the present investigation is to trace the effect of eccentric transverse loading of full scale connections with slotted-in steel plates primarily loaded in the grain direction....
Overcoming maladaptive plasticity through plastic compensation
Directory of Open Access Journals (Sweden)
Matthew R.J. MORRIS, Sean M. ROGERS
2013-08-01
Full Text Available Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes (standing genetic variation, genetic compensation and two of which do not (standing epigenetic variation, plastic compensation. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change [Current Zoology 59 (4: 526–536, 2013].
Overcoming maladaptive plasticity through plastic compensation
Institute of Scientific and Technical Information of China (English)
Matthew R.J.MORRIS; Sean M.ROGERS
2013-01-01
Most species evolve within fluctuating environments,and have developed adaptations to meet the challenges posed by environmental heterogeneity.One such adaptation is phenotypic plasticity,or the ability of a single genotype to produce multiple environmentally-induced phenotypes.Yet,not all plasticity is adaptive.Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution,much less is known about maladaptive plasticity.However,maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments.This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity,two of which involve genetic changes (standing genetic variation,genetic compensation) and two of which do not (standing epigenetic variation,plastic compensation).Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity.In particular,plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence.We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change.
Two-Dimensional Large Deformation Finite Element Analysis for the Pulling-up of Plate Anchor
Institute of Scientific and Technical Information of China (English)
WANG Dong; HU Yu-xia; JIN Xia
2006-01-01
Based on mesh regeneration and stress interpolation from an old mesh to a new one, a large deformation finite element model is developed for the study of the behaviour of circular plate anchors subjected to uplift loading. For the determination of the distributions of stress components across a clay foundation, the Recovery by Equilibrium in Patches is extended to plastic analyses. ABAQUS, a commercial finite element package, is customized and linked into our program so as to keep automatic and efficient running of large deformation calculation. The quality of stress interpolation is testified by evaluations of Tresca stress and nodal reaction forces. The complete pulling-up processes of plate anchors buried in homogeneous clay are simulated, and typical pulling force-displacement responses of a deep anchor and a shallow anchor are compared. Different from the results of previous studies, large deformation analysis is of the capability of estimating the breakaway between the anchor bottom and soils. For deep anchors, the variation of mobilized uplift resistance with anchor settlement is composed of three stages, and the initial buried depths of anchors affect the separation embedment slightly. The uplift bearing capacity of deep anchors is usually higher than that of shallow anchors.
Circular dichroism techniques: biomolecular and nanostructural analyses- a review.
Ranjbar, Bijan; Gill, Pooria
2009-08-01
This paper reviews the best known techniques using circular dichroism spectroscopy such as conventional circular dichroism (i.e. electronic circular dichroism), magnetic circular dichroisms (magnetic vibrational circular dichroism, x-ray magnetic circular dichroism), fluorescence detected circular dichroism, near-infrared circular dichroism, vibrational circular dichroism, Fourier transform infrared circular dichroism, high pressure liquid chromatography circular dichroism, stopped-flow circular dichroism, and synchrotron radiation circular dichroism. Also, we have described here the most important applications of circular dichroism spectroscopy in structural biochemistry and nanoscience.
DEFF Research Database (Denmark)
Christensen, Thomas Højlund; Fruergaard, Thilde
2011-01-01
Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...
Circular RNAs in heart failure.
Devaux, Yvan; Creemers, Esther E; Boon, Reinier A; Werfel, Stanislas; Thum, Thomas; Engelhardt, Stefan; Dimmeler, Stefanie; Squire, Iain
2017-06-01
Cardiovascular disease, and particularly heart failure, is still a serious health care issue for which novel treatments and biomarkers are needed. The RNA family comprises different subgroups, among which the small-sized microRNAs and the larger long non-coding RNAs have shown some potential to aid in moving personalized health care of heart failure patients a step forward. Here, members of the Cardiolinc network review the recent findings suggesting that the less well-known circular RNAs may constitute a novel reservoir of therapeutic targets and biomarkers of heart failure. The knowledge of the mode of biogenesis of circular RNAs will first be reported, followed by a description of different features that make these RNA molecules of interest for the heart failure community. The functions of circular RNAs in the heart will be described, with some emphasis given to their regulation in the failing heart. Circulating in the bloodstream, circular RNAs have appeared as potential biomarkers and recent findings associated with the use of circular RNAs as heart failure biomarkers will be discussed. Finally, some directions for future research will be provided. © 2017 The Authors. European Journal of Heart Failure © 2017 European Society of Cardiology.
Institute of Scientific and Technical Information of China (English)
武传松; 张文斌; 石磊; 陈茂爱
2012-01-01
Thin copper sheets as marker material were embedded into weld path of 2024 aluminium alloy plates and their final position after friction stir welding was examined by metallographic techniques.Referring to the visualized material flow patterns,a three-dimensional model was developed to conduct the numerical simulation of the temperature profile and plastic material flow in friction stir welding.The calculated velocity contour of plastic flow in close proximity of the tool is generally consistent with the visualized results.As the tool rotation speed increases at a constant tool travel speed,the material flow near the pin gets stronger.The predicted shape and size of the weld nugget zone match with the experimentally measured ones.%将薄铜片作为标示材料镶嵌于2024铝合金板中,经搅拌摩擦焊接焊后,用金相法观察其最终位置.参考材料流动的可视化实验结果,建立搅拌摩擦焊传热与材料流动的三维数值分析模型.搅拌针附近塑性材料流动速度分布模式的计算结果与可视化实验结果基本一致.当焊接速度一定时,随搅拌针旋转速度的提高,搅拌针附近塑性材料流动加剧.焊核区形状与尺寸的计算结果与实测数据吻合.
LAMP Joining between Ceramic and Plastic
Kawahito, Yousuke; Nishimoto, Kouji; Katayama, Seiji
Joining of dissimilar materials is necessary and important from a manufacturing viewpoint. Therefore, the authors have developed a new laser direct joining method between a metal and a plastic which is named Laser Assisted Metal and Plastic (LAMP) joining method. In this research, LAMP joining was applied to join silicon nitride Si3N4 ceramic and polyethylene terephthalate (PET) engineering plastic, although metal was replaced by ceramic. The tensile shear strength of obtained joints was 3100 N at the maximum, which was strong enough to elongate a PET base plate of 2 mm in thickness and 30 mm in width. Moreover, transmission electron microscopes (TEM) observation demonstrates that the ceramic and the plastic are tightly bonded on atomic or molecular sized level.
Theoretical modelling of non-symmetric circular piezoelectric bimorphs
Brissaud, Michel
2006-05-01
This paper deals with the theoretical modelling of non-symmetric and symmetric circular bimorphs. The model is restricted to the study of flexural vibration modes having radial symmetry (axisymmetry), as is often the case for piezoelectric devices such as MEMs. The calculation of the resonance frequencies and the displacement of the non-symmetric circular bimorph has been carried out and the influence of the elastic and geometric parameters of the cement layer has been introduced into the model. As is shown, the modelling of non-symmetric and symmetric circular bimorphs reduces to the determination of two global quantities: the global rigidity DG and the global Poisson ratio σG of the bimorph which is then equivalent to a homogenous element. Consequently, the results obtained with elastic and homogeneous circular plates can be applied to non-symmetric and symmetric bimorphs with the only condition of using the global DG and σG. The new modelling was applied to bimorph functioning either as an actuator or as a sensor and having a simply supported or clamped edge. The electromechanical coupling factor of flexure modes has been calculated and compared to the radial mode. Comparison between analytical models and simulations using the finite-element method is given and discussed.
A New Limit on CMB Circular Polarization from SPIDER
Nagy, J. M.; Ade, P. A. R.; Amiri, M.; Benton, S. J.; Bergman, A. S.; Bihary, R.; Bock, J. J.; Bond, J. R.; Bryan, S. A.; Chiang, H. C.; Contaldi, C. R.; Doré, O.; Duivenvoorden, A. J.; Eriksen, H. K.; Farhang, M.; Filippini, J. P.; Fissel, L. M.; Fraisse, A. A.; Freese, K.; Galloway, M.; Gambrel, A. E.; Gandilo, N. N.; Ganga, K.; Gudmundsson, J. E.; Halpern, M.; Hartley, J.; Hasselfield, M.; Hilton, G.; Holmes, W.; Hristov, V. V.; Huang, Z.; Irwin, K. D.; Jones, W. C.; Kuo, C. L.; Kermish, Z. D.; Li, S.; Mason, P. V.; Megerian, K.; Moncelsi, L.; Morford, T. A.; Netterfield, C. B.; Nolta, M.; Padilla, I. L.; Racine, B.; Rahlin, A. S.; Reintsema, C.; Ruhl, J. E.; Runyan, M. C.; Ruud, T. M.; Shariff, J. A.; Soler, J. D.; Song, X.; Trangsrud, A.; Tucker, C.; Tucker, R. S.; Turner, A. D.; Van Der List, J. F.; Weber, A. C.; Wehus, I. K.; Wiebe, D. V.; Young, E. Y.
2017-08-01
We present a new upper limit on cosmic microwave background (CMB) circular polarization from the 2015 flight of Spider, a balloon-borne telescope designed to search for B-mode linear polarization from cosmic inflation. Although the level of circular polarization in the CMB is predicted to be very small, experimental limits provide a valuable test of the underlying models. By exploiting the nonzero circular-to-linear polarization coupling of the half-wave plate polarization modulators, data from Spider's 2015 Antarctic flight provide a constraint on Stokes V at 95 and 150 GHz in the range 33Spider improves on the previous limit by several orders of magnitude, providing 95% C.L. constraints on {\\ell }({\\ell }+1){C}{\\ell }{VV}/(2π ) ranging from 141 to 255 μK2 at 150 GHz for a thermal CMB spectrum. As linear CMB polarization experiments become increasingly sensitive, the techniques described in this paper can be applied to obtain even stronger constraints on circular polarization.
Photoelectron circular dichroism of isopropanolamine
Catone, D.; Turchini, S.; Contini, G.; Prosperi, T.; Stener, M.; Decleva, P.; Zema, N.
2017-01-01
Spectroscopies based on circular polarized light are sensitive to the electronic and structural properties of chiral molecules. Photoelectron circular dichroism (PECD) is a powerful technique that combines the chiral sensitivity of the circular polarized light and the electronic information obtained by photoelectron spectroscopy. An experimental and theoretical PECD study of the outer valence and C 1s core states of 1-amino-2-propanol in the gas phase is presented. The experimental dichroic dispersions in the photoelectron kinetic energy are compared with theoretical calculations employing a multicentric basis set of B-spline functions and a Kohn-Sham Hamiltonian. In order to understand analogies and differences in the dichroism of structural isomers bearing the same functional groups, a comparison with previous PECD study of valence band of 2-amino-1-propanol is carried out.
Ecodesign for a Circular Economy
DEFF Research Database (Denmark)
Bundgaard, Anja Marie
The Earth is a closed system and with the exception of energy, the resources available to us are finite, but our consumption and productions systems are typically linear systems where resources are extracted, used and wasted. The circular economy is proposed as an alternative and is defined...... as a consumption and production system based on closed loops that minimise resources, energy flows and environmental degradation. In this PhD thesis, I have examined how ecodesign can close the material loops in the circular economy for electrical and electronic equipment. The study examines how to improve...... be necessary to develop both product and company specific guidelines. The analysis revealed that activities or product attributes of importance to a circular economy are not solely driven by ecodesign....
Institute of Scientific and Technical Information of China (English)
饶荣; 宋明; 成昊; 邱祖民
2015-01-01
×aste ABS plastics were stripped with the solution mixed of hydrochloric acid and hydrogen perox-ide,and electrolytic process was employed to recycle copper aften stripping. Effects of process conditions on current efficiency and copper recovery rate,such as ampere density,electrolyte circulation flow,electrode spacing and elec-trolytic duration,were further studied through single factor and orthogonal test methods to determine the optimum pa-rameters of copper recovery processing. Finally,the optimal process conditions were carried out:Current density, 416. 0 A/m2;Electrode spacing,1. 4 cm;Solution circulation flow,3. 0 L/h;Electrolytic duration,40 min.%采用盐酸和双氧水构建的溶液对废ABS塑料电镀件进行退镀，退镀液中含铜、镍等金属，采用电解法回收退镀液中的铜。通过单因素及正交试验法，考察了电流密度、电解液循环流量、电极距、电解时间等工艺条件对电流效率及铜回收率的影响，确定了铜回收过程的最佳工艺参数：电流密度416.0 A/m2、电极距1.4 cm、溶液循环流量3.0 L/h、电解时间40 min。
Implementing circularity using partial evaluation
DEFF Research Database (Denmark)
Lawall, Julia Laetitia
2001-01-01
of an imperative C-like language, by extending the language with a new construct, persistent variables. We show that an extension of partial evaluation can eliminate persistent variables, producing a staged C program. This approach has been implemented in the Tempo specializer for C programs, and has proven useful......Complex data dependencies can often be expressed concisely by defining a variable in terms of part of its own value. Such a circular reference can be naturally expressed in a lazy functional language or in an attribute grammar. In this paper, we consider circular references in the context...
Logistic regression for circular data
Al-Daffaie, Kadhem; Khan, Shahjahan
2017-05-01
This paper considers the relationship between a binary response and a circular predictor. It develops the logistic regression model by employing the linear-circular regression approach. The maximum likelihood method is used to estimate the parameters. The Newton-Raphson numerical method is used to find the estimated values of the parameters. A data set from weather records of Toowoomba city is analysed by the proposed methods. Moreover, a simulation study is considered. The R software is used for all computations and simulations.
Circular threshold quantum secret sharing
Institute of Scientific and Technical Information of China (English)
Yang Yu-Guang; Wen Qiao-Yan
2008-01-01
This paper proposes a circular threshold quantum secret sharing (TQSS) scheme with polarized single photons.A polarized single photon sequence runs circularly among any t or more of n parties and any t or more of n parties can reconstruct the secret key when they collaborate.It shows that entanglement is not necessary for quantum secret sharing.Moreover,the theoretic efficiency is improved to approach 100% as the single photons carrying the secret key are deterministically forwarded among any t or more of n parties,and each photon can carry one bit of information without quantum storage.This protocol is feasible with current technology.
PLASTIC LIMIT ANALYSIS OF DISCONTINUOUS LINING UNDERGROUND PRESSURE
Institute of Scientific and Technical Information of China (English)
龙春安
1999-01-01
Discontinuous lining is a special form of support in underground excavation. Based on the method of plastic limit analysis, it is found the upper and the lower bound solution of the pressure of circular discontinuous lining and discussed support parameter of discontinuous lining and its applicable conditions, which provides theoretical basis for the design and calculation of discontinuous lining.
Fatigue Behavior for Composite Laminates with Circular Hole
Institute of Scientific and Technical Information of China (English)
Qi Hongyu; Wen Weidong; Sun Lianwen
2004-01-01
Based on the fatigue model of exponential function and WN criterion of static strength for the composite material laminates with a circular hole, the stress correct factorβ is presented. In order to gain the factorβ, the fatigue experiments of laminates with holes in different diameters and the same ratio of width and diameter. The fatigue behavior is usually accompanied with extensive damages. Those damages can affect composite materials in their strength and stiffness. The new model based on damage theory and strain equivalent hypothesis meets engineering requirement.T300/KH304, which is recently studied, is a high capability composite material. The fatigue analysis and tests of laminates with a hole in diameter of 5 mm are carried under difference stress levels. The simple, prompt and practical method was provided for the predication of fatigue life of composite material plate with a circular hole.
Modeling of plates with multiple anisotropic layers and residual stress
DEFF Research Database (Denmark)
Engholm, Mathias; Pedersen, Thomas; Thomsen, Erik Vilain
2016-01-01
Usually the analytical approach for modeling of plates uses the single layer plate equation to obtain the deflection and does not take anisotropy and residual stress into account. Based on the stress–strain relation of each layer and balancing stress resultants and bending moments, a general...... multilayered anisotropic plate equation is developed for plates with an arbitrary number of layers. The exact deflection profile is calculated for a circular clamped plate of anisotropic materials with residual bi-axial stress.From the deflection shape the critical stress for buckling is calculated......, and an excellent agreement between the two models is seen with a relative difference of less than 2% for all calculations. The model was also used to extract the cell capacitance, the parasitic capacitance and the residual stress of a pressure sensor composed of a multilayered plate of silicon and silicon oxide...
MECHANISM AND CATASTROPHE THEORY ANALYSIS OF CIRCULAR TUNNEL ROCKBURST
Institute of Scientific and Technical Information of China (English)
PAN Yue; ZHANG Yong; YU Guang-ming
2006-01-01
Mechanism of circular tunnel rockburst is that, when the carrying capacity of the centralized zone of plastic deformation in limiting state reduces, the comparatively intact part in rock mass unloads by way of elasticity; rockburst occurs immediately when the elastic energy released by the comparatively intact part exceeds the energy dissipated by plastic deformation. The equivalent strain was taken as a state variable to establish a catastrophe model of tunnel rockburst, and the computation expression of the earthquake energy released by tunnel rockburst was given. The analysis shows that, the conditions of rockburst occurrence are relative to rock's ratio of elastic modulus to descendent modulus and crack growth degree of rocks; to rock mass with specific rockburst tendency, there exists a corresponding critical depth of softened zone, and rockburst occurs when the depth of softened zone reaches.
Best Practice Examples of Circular Business Models
DEFF Research Database (Denmark)
Guldmann, Eva
, and to look for circular business opportunities in this flow of goods and value, is key in a circular economy. Establishing new or closer collaboration with stakeholders within or beyond the traditional supply chain is another important skill in creating circular business models. Many of the examined......Best practice examples of circular business models are presented in this report. The purpose is to inform and inspire interested readers, in particular companies that aspire to examine the potentials of the circular economy. Circular business models in two different sectors are examined, namely...... the textile and clothing sector as well as the durable goods sector. In order to appreciate the notion of circular business models, the basics of the circular economy are outlined along with three frameworks for categorizing the various types of circular business models. The frameworks take point of departure...
2015-07-01
UNCLASSIFIED UNCLASSIFIED Linear-Elastic 2D and 3D Finite Element Contact Analysis of a Hole Containing a Circular Insert in a Fatigue Test...circular hole in an aluminium plate fitted with a titanium fastener that were computed using two-dimensional finite element contact analysis . By...UNCLASSIFIED Linear-Elastic 2D and 3D Finite Element Contact Analysis of a Hole Containing a Circular Insert in a Fatigue Test Coupon
Class IIc or Circular Bacteriocins
Martin-Visscher, Leah A.; van Belkum, Marco J.; Vederas, John C.
The circular bacteriocins produced by Gram-positive bacteria represent a diverse class of antimicrobial peptides. These bacteriocins display enhanced stability compared to linear bacteriocins, which arises from their characteristic circular backbone. Currently, eight unique circular bacteriocins have been identified, and analysis of their gene clusters indicates that they likely utilize complex mechanisms for maturation and secretion, as well as for immunity. These bacteriocins target the cytoplasmic membrane of sensitive cells, leading to pore formation that results in loss of ions, dissipation of membrane potential, and ultimately, cell death. Structural studies suggest that despite variation in their sequences, most of these bacteriocins likely adopt a common three-dimensional architecture, consisting of four or five tightly packed helices encompassing a hydrophobic core. There are many mysteries surrounding the biosynthesis of these peptides, particularly in regard to the mechanism by which they are cyclized. Elucidation of such a mechanism may provide exciting new approaches to the bioengineering of new, stable, and antimicrobially active circular peptides.
Circular polarization in relativistic jets
Macquart, JP
2003-01-01
Circular polarization is observed in some relativistic jet sources at radio wavelengths. It is largely associated with activity in the cores of the radio sources, is highly variable, and is strongest during ejection episodes. VLBI imaging and interstellar scintillation arguments show that the degree
140 CIRCULAR INTERACTION BETWEEN LINGUISTIC ...
African Journals Online (AJOL)
linguistic discipline to which close attention will be payed in this paper, is ..... Similar data was pOinted out for the Benue-Cross language Gokana by Wagner .... language departments have a circular influence on each other but theory and.
Circular polarization observed in bioluminescence
Wijnberg, Hans; Meijer, E.W.; Hummelen, J.C.; Dekkers, H.P.J.M.; Schippers, P.H.; Carlson, A.D.
1980-01-01
While investigating circular polarization in luminescence, and having found it in chemiluminescence, we have studied bioluminescence because it is such a widespread and dramatic natural phenomenon. We report here that left and right lanterns of live larvae of the fireflies, Photuris lucicrescens and
Uniform circular array for structural health monitoring of composite structures
Stepinski, Tadeusz; Engholm, Marcus
2008-03-01
Phased array with all-azimuth angle coverage would be extremely useful in structural health monitoring (SHM) of planar structures. One method to achieve the 360° coverage is to use uniform circular arrays (UCAs). In this paper we present the concept of UCA adapted for SHM applications. We start from a brief presentation of UCA beamformers based on the principle of phase mode excitation. UCA performance is illustrated by the results of beamformer simulations performed for the narrowband and wideband ultrasonic signals. Preliminary experimental results obtained with UCA used for the reception of ultrasonic signals propagating in an aluminum plate are also presented.
Recycling of Reinforced Plastics
Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri
2014-02-01
This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.
Processless offset printing plates
Directory of Open Access Journals (Sweden)
Sanja Mahović Poljaček
2015-06-01
Full Text Available With the implementation of platesetters in the offset printing plate making process, imaging of the printing plate became more stable and ensured increase of the printing plate quality. But as the chemical processing of the printing plates still highly influences the plate making process and the graphic reproduction workflow, development of printing plates that do not require chemical processing for offset printing technique has been one of the top interests in graphic technology in the last few years. The main reason for that came from the user experience, where majority of the problems with plate making process could be connected with the chemical processing of the printing plate. Furthermore, increased environmental standards lead to reducing of the chemicals used in the industrial processes. Considering these facts, different types of offset printing plates have been introduced to the market today. This paper presents some of the processless printing plates.
RAYLEIGH LAMB WAVES IN MICROPOLAR ISOTROPIC ELASTIC PLATE
Institute of Scientific and Technical Information of China (English)
Rajneesh Kumar; Geeta Partap
2006-01-01
The propagation of waves in a homogeneous isotropic micropolar elastic cylindrical plate subjected to stress free conditions is investigated. The secular equations for symmetric and skew symmetric wave mode propagation are derived. At short wave limit,the secular equations for symmetric and skew symmetric waves in a stress free circular plate reduces to Rayleigh surface wave frequency equation. Thin plate results are also obtained. The amplitudes of displacements and microrotation components are obtained and depicted graphically. Some special cases are also deduced from the present investigations. The secular equations for symmetric and skew symmetric modes are also presented graphically.
Heat transfer due to impinging double free circular jets
Directory of Open Access Journals (Sweden)
Mohamed A. Teamah
2015-09-01
Full Text Available The heat transfer and fluid flow between a horizontal heated plate and impinging circular double jets were studied experimentally. The parameters investigated are the Reynolds number of each jet and jet-to-jet spacing. Experiments are carried out covering a range for Reynolds number from 7100 to 30,800 for each jet, the dimensionless jet-to-jet spacing from 22.73 to 90.1. During experimental phases, the right jet Reynolds number was higher than the left jet Reynolds number. The isothermal contours were plotted for different cases as well as the distribution of water film thickness over the heated plate. The results indicated that increasing the Reynolds number of one jet than the other increases both local and average Nusselt numbers. In addition, increasing the jet-to-jet spacing at the same Reynolds number increases the average Nusselt number.
DEFF Research Database (Denmark)
Christensen, Thomas Højlund; Fruergaard, Thilde
2011-01-01
Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, for example, gutters, window frames, car parts and transportation boxes have long lifetimes and thus appear as waste only many years after they have been introduced on the market. Plastic is constantly being used for new products because of its attractive material properties: relatively cheap, easy to form......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...
Directory of Open Access Journals (Sweden)
Hai Shi
2017-01-01
Full Text Available With the conformal mapping function provided by Verruijt, the outland of a noncircular tunnel can be mapped to a circular unit in the complex plane and then spread the analytic function into a Laurent series. The stress unified solution of oval and horseshoe cross section can be determined using Muskhelishvili’s complex variables function method. Subsequently, the solution can be taken into the Griffith strength failure criterion and determine the scale and shape of plastic zone in the tunnel surrounding rock. Aiming at the critical safety thickness between a concealed cave and tunnel in the karst area and determining whether the plastic zone of tunnel surrounding rock is connected with the plastic zone of cave as a judgment standard, the model of critical safety thickness among the concealed caves and tunnels is established. The numerical model is established in comparison with the computing method of rock plate critical safety thickness in actual engineering based on the Doumo tunnel engineering of Shanghai-Kunming (Guizhou segment high-speed railway. The following conclusions can be drawn: the analytical approximation method has less indexes, and the output of this method is approximately close to actual engineering and numerical analysis, in which it is reliable and rational.
Dynamics of Shells and Fluid-Loaded Plates.
Wang, Zhang
This thesis is composed of two parts. The first part is concerned with wave propagation on elastic structures in vacuum. An asymptotic approximation is obtained for the dispersion relation of flexural waves propagating in an infinite, flat plate, with material and/or geometric properties periodic in one direction. A matrix approach is proposed to investigate waves in circular cylindrical thin shells joined with circular plates. Both the general propagator matrix and S-matrix formalisms are presented, with emphasis on the latter. The second part is devoted to structures with ambient fluid loading. The Green's function for a fluid-loaded plate under line loading is expressed as a sum of five fluid-loaded plate waves and an acoustic wave with magnitude given by an infinite integral, similar to a branch cut integral. A scattering matrix approach is presented to solve wave propagation problems on fluid-loaded plates with attached ribs. The low frequency asymptotic dispersion relation for a fluid-loaded plate with infinite number of equally spaced identical ribs is derived, from which an equation of motion for the plate is inferred which is valid also at low frequencies.
Study on Geosynchronous Circular SAR
Directory of Open Access Journals (Sweden)
Hong Wen
2015-06-01
Full Text Available The concept of Geosynchronous Circular SAR (Geo-CSAR is introduced in this paper. With the design of the geosynchronous orbit parameters, a near-circular satellite sub-track could be formed to enable the staring imaging mode, which supports the advanced applications for wide-field and 3-D information acquisition under long-term consistent observation. This paper also analyzes Geo-CSAR's imaging formation capabilities, and concludes its attractive advantages over low-earth orbit spaceborne SAR in terms of instantaneous coverage, consistent observing area, 3-D positioning accuracy and etc.. Encouraging expectations for Geo-CSAR thus could be positively predicted in military investigation and disaster monitoring management applications.
Gohil, Trushar B; Muralidhar, K
2010-01-01
The present study report direct numerical simulation (DNS) of a circular jet and the effect of a large scale perturbation at the jet inlet. The perturbation is used to control the jet for increased spreading. Dual-mode perturbation is obtained by combining an axisymmetric excitation with the helical. In the fluid dynamics videos, an active control of the circular jet at a Reynolds number of 2000 for various frequency ratios (both integer and non-integer) has been demonstrated. When the frequency ratio is fixed to 2, bifurcation of the jet on a plane is evident. However, for a non-integer frequency ratio, the axisymmetric jet is seen to bloom in all directions.
Insights into circular RNA biology
DEFF Research Database (Denmark)
Ebbesen, Karoline K; Hansen, Thomas B; Kjems, Jørgen
2016-01-01
Circular RNAs (circRNAs) are a novel class of non-coding RNA characterized by a covalently closed-loop structure generated through a special type of alternative splicing termed backsplicing. CircRNAs are emerging as a heterogeneous class of molecules involved in modulating gene expression by regu...... and lastly, an outlook with a focus on unanswered questions regarding circRNA biology will be included....
Granger causality for circular variables
Energy Technology Data Exchange (ETDEWEB)
Angelini, Leonardo; Pellicoro, Mario [Istituto Nazionale di Fisica Nucleare, Sezione di Bari (Italy); Dipartimento di Fisica, University of Bari (Italy); Stramaglia, Sebastiano, E-mail: sebastiano.stramaglia@ba.infn.i [Istituto Nazionale di Fisica Nucleare, Sezione di Bari (Italy); Dipartimento di Fisica, University of Bari (Italy)
2009-06-29
In this Letter we discuss the use of Granger causality to the analyze systems of coupled circular variables, by modifying a recently proposed method for multivariate analysis of causality. We show the application of the proposed approach on several Kuramoto systems, in particular one living on networks built by preferential attachment and a model for the transition from deeply to lightly anaesthetized states. Granger causalities describe the flow of information among variables.
Capacitance of circular patch resonator
Energy Technology Data Exchange (ETDEWEB)
Miano, G.; Verolino, L. [Dip. di Ingegneria Elettrica, Ist. Nazionale di Fisica Nucleare, Naples (Italy); Panariello, G. [Dip. di Ingegneria Elettronica, Naples (Italy); Vaccaro, V.G. [Ist. Nazionale di Fisica Nucleare, Naples (Italy). Dipt. di Scienze Fisiche
1995-11-01
In this paper the capacitance of the circular microstrip patch resonator is computed. It is shown that the electrostatic problem can be formulated as a system of dual integral equations, and the most interesting techniques of solutions of these systems are reviewed. Some useful approximated formulas for the capacitance are derived and plots of the capacitance are finally given in a wide range of dielectric constants.
The Effect of the Configuration of the Absorber on the Performance of Flat Plate Thermal Collector
Yan, Moyu; Qu, Ming; Peng, Steve
2016-01-01
In this study, a numerical thermal analysis for a new designed flat plate thermal collector was conducted through modeling. The new flat plate thermal collector has ellipse shaped tubes inside a wavy shaped absorber, which is made of stainless steel. For the comparison, the conventional flat plate thermal collector with circular copper tubes served as a base case was also modeled. Hottel-Whillier equations were utilized to formulate thermal networks for both models developed in Engineering Eq...
2012-09-06
... Employment and Training Administration Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A... plastic parts. New information shows that Fortis Plastics is now called Carlyle Plastics and Resins. In... of Carlyle Plastics and Resins, formerly known as Fortis Plastics, a subsidiary of...
Circular Polarization in Pulsar Integrated Profiles: Updates
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
We update the systematic studies of circular polarization in integrated pulse profiles by Han et al. Data of circular polarization profiles are compiled. Sense reversals can occur in core or cone components, or near the intersection between components. The correlation between the sense of circular polarization and the sense of position angle variation for conal-double pulsars is confirmed with a much large database. Circular polarization of some pulsars has clear changes with frequency.Circular polarization of millisecond pulsars is marginally different from that of normal pulsars.
Li, Heng-Xiang; Orihuela, Beatriz; Zhu, Mei; Rittschof, Daniel
2016-11-01
Plastics are common and pervasive anthropogenic debris in marine environments. Floating plastics provide opportunities to alter the abundance, distribution and invasion potential of sessile organisms that colonize them. We selected plastics from seven recycle categories and quantified settlement of (i) bryozoans Bugula neritina (Linnaeus, 1758) in the lab and in the field, and of (ii) barnacles Amphibalanus (= Balanus) amphitrite (Darwin, 1854) in the field. In the laboratory we cultured barnacles on the plastics for 8 weeks and quantified growth, mortality, and breaking strength of the side plates. In the field all recyclable plastics were settlement substrata for bryozoans and barnacles. Settlement depended on the type of plastic. Fewer barnacles settled on plastic surfaces compared to glass. In the lab and in the field, bryozoan settlement was higher on plastics than on glass. In static laboratory rearing, barnacles growing on plastics were initially significantly smaller than on glass. This suggested juvenile barnacles were adversely impacted by materials leaching from the plastics. Barnacle mortality was not significantly different between plastic and glass surfaces, but breaking strength of side plates of barnacles on polyvinyl chloride (PVC) and polycarbonate (PC) were significantly lower than breakage strength on glass. Plastics impact marine ecosystems directly by providing new surfaces for colonization with fouling organisms and by contaminants shown previously to leach out of plastics and impact biological processes.
Microbial contamination in intraoral phosphor storage plates: the dilemma.
de Souza, Tricia Murielly Pereira Andrade; de Castro, Ricardo Dias; de Vasconcelos, Laís César; Pontual, Andréa Dos Anjos; de Moraes Ramos Perez, Flávia Maria; Pontual, Maria Luiza Dos Anjos
2017-01-01
The aims of this study were to evaluate microbial contamination in phosphor storage plates in dental radiology services and discuss the possible origin of this contamination. The sample comprised 50 phosphor plates: 14 plates from service A, 30 from service B, and 6 in the control group, consisting of plates never used. Damp sterile swabs were rubbed on the phosphor plates, and then transferred to tests tubes containing sterile saline solution. Serial dilutions were made, and then inoculated in triplicate on Mueller Hinton agar plates and incubated at 37 °C/48 h, before counting the colony-forming units (CFU). The samples were also seeded in brain-heart infusion medium to confirm contamination by turbidity of the culture medium. All solutions, turbid and clean, were seeded in selective and non-selective media. At service A and B, 50 and 73.3 % of the phosphor plates were contaminated, respectively. This contamination was mainly due to bacteria of the genus Staphylococcus. CFU counts ranged from 26.4 to 80.0 CFU/plate. Most of the phosphor plates evaluated shown to be contaminated, mainly by Staphylococcus ssp. Quantitatively, this contamination occurred at low levels, possibly arising from handling of the plates. The use of a second plastic barrier may have diminished contamination by microorganisms from the oral cavity. There is a risk of cross-contamination by phosphor storage plates used in dental radiology services.
National Research Council Canada - National Science Library
Richard C. Thompson; Shanna H. Swan; Charles J. Moore; Frederick S. vom Saal
2009-01-01
Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production...
Foekema, E.M.
2012-01-01
Waar de magen van sommige zeevogels vol plastic zitten, lijken vissen in de Noordzee nauwelijks last te hebben van kunststofafval. Onderzoekers die plastic resten zochten in vissenmagen vonden ze in elk geval nauwelijks.
... ENTCareers Marketplace Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...
Circular permutation of a synthetic eukaryotic chromosome with the telomerator
Mitchell, Leslie A.; Boeke, Jef D.
2014-01-01
Chromosome engineering is a major focus in the fields of systems biology, genetics, synthetic biology, and the functional analysis of genomes. Here, we describe the “telomerator,” a new synthetic biology device for use in Saccharomyces cerevisiae. The telomerator is designed to inducibly convert circular DNA molecules into mitotically stable, linear chromosomes replete with functional telomeres in vivo. The telomerator cassette encodes convergent yeast telomere seed sequences flanking the I-SceI homing endonuclease recognition site in the center of an intron artificially transplanted into the URA3 selectable/counterselectable auxotrophic marker. We show that inducible expression of the homing endonuclease efficiently generates linear molecules, identified by using a simple plate-based screening method. To showcase its functionality and utility, we use the telomerator to circularly permute a synthetic yeast chromosome originally constructed as a circular molecule, synIXR, to generate 51 linear variants. Many of the derived linear chromosomes confer unexpected phenotypic properties. This finding indicates that the telomerator offers a new way to study the effects of gene placement on chromosomes (i.e., telomere proximity). However, that the majority of synIXR linear derivatives support viability highlights inherent tolerance of S. cerevisiae to changes in gene order and overall chromosome structure. The telomerator serves as an important tool to construct artificial linear chromosomes in yeast; the concept can be extended to other eukaryotes. PMID:25378705
Injection molding of micro patterned PMMA plate
Institute of Scientific and Technical Information of China (English)
Yeong-Eun YOO; Tae-Hoon KIM; Tae-Jin JE; Doo-Sun CHOI; Chang-Wan KIM; Sun-Kyung KIM
2011-01-01
A plastic plate with surface micro features was injection molded to investigate the effect of pressure rise of melt on the replication of the micro structures. Prism pattern, which is used in many optical applications, was selected as a model pattern. The prism pattern is 50 μm in pitch and 108° in the vertical angle. The overall size of the plate was 335 mm×213 mm and the thickness of the plate varied linearly from 2.6 mm to 0.7 mm. The prism pattern was firstly machined on the nickel plated core block using micro diamond tool and this machined pattern core was installed in a mold for injection molding of prism patterned plate. Polymethyl methacrylate (PMMA) was used as a molding material. The pressure and temperature of the melt in the cavity were measured at different positions in the cavity and the replication of the pattern was also measured at the same positions. The results show that the pressure or temperature profile through the process depends on the shape and the size of the plate. The replication is affected by the temperature and pressure profiles at the early stage of filling, which is right after the melt reaches the position to be measured.
What foods are US supermarkets promoting? A content analysis of supermarket sales circulars.
Martin-Biggers, Jennifer; Yorkin, Meredith; Aljallad, Carena; Ciecierski, Caroline; Akhabue, Ivbaria; McKinley, Jessica; Hernandez, Katherine; Yablonsky, Courtney; Jackson, Rachel; Quick, Virginia; Byrd-Bredbenner, Carol
2013-03-01
This study compared the types of foods advertised in supermarket newspaper circulars across geographic region (US Census regions: northeast [n=9], midwest [n=15], south [n=14], and west [n=13]), obesity-rate region (i.e., states with CDC adult obesity rates of advertisements on the first page of each circular were measured (±0.12-in.) to determine the proportion of space occupied and categorized according to food group. Overall, ≥ 50% of the front page of supermarket sales circulars was devoted to protein foods and grains; fruits, vegetables, and dairy, combined, were allocated only about 25% of the front page. The southern geographic region and the highest obesity-rate region both devoted significantly more advertising space to sweets, particularly sugar-sweetened beverages. The lowest obesity-rate region and western geographic region allocated the most space to fruits. Vegetables were allocated the least space in the western geographic region. Grains were the only food group represented in ads in proportions approximately equal to amounts depicted in the MyPlate icon. Protein foods exceeded and fruits, dairy, and vegetables fell below comparable MyPlate proportional areas. Findings suggest supermarket ads do not consistently emphasize foods that support healthy weight and MyPlate recommendations. More research is needed to determine how supermarket newspaper circulars can be used to promote healthy dietary patterns.
Yutaka Tokiwa; Calabia, Buenaventurada P.; Charles U. Ugwu; Seiichi Aiba
2009-01-01
Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical ...
Investigation of the plastic fracture of high strength steels
Cox, T. B.; Low, J. R., Jr.
1972-01-01
This investigation deals in detail with the three recognized stages of plastic fracture in high strength steels, namely, void initiation, void growth, and void coalescence. The particular steels under investigation include plates from both commercial purity and high purity heats of AISI 4340 and 18 Ni, 200 grade maraging steels. A scanning electron microscope equipped with an X-ray energy dispersive analyzer, together with observations made using light microscopy, revealed methods of improving the resistance of high strength steels to plastic fracture.
Directory of Open Access Journals (Sweden)
Sara Fatima
2014-11-01
Full Text Available Various chemical processes currently prevalent in the chemical industry for plastics recycling have been discussed. Possible future scenarios in chemical recycling have also been discussed. Also analyzed are the effects on the environment, the risks, costs and benefits of PVC recycling. Also listed are the various types of plastics and which plastics are safe to use and which not after rcycle
DEFF Research Database (Denmark)
Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin
2014-01-01
Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example...
Full Text Available ... steps to get started: Using your dinner plate, put a line down the middle of the plate. ... vegetables . Now in one of the small sections, put grains and starchy foods. See this list of ...
Full Text Available ... Your Plate It's simple and effective for both managing diabetes and losing weight. Creating your plate lets ... 2016 Articles from Diabetes Forecast® magazine: wcie-meal-planning, In this section Food Planning Meals Diabetes Meal ...
Full Text Available ... Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal ... Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook ...
... chips or cookies. VEGETABLES: MAKE HALF OF YOUR PLATE FRUITS AND VEGETABLES Vegetables can be raw, fresh, ... as a snack. FRUITS: MAKE HALF OF YOUR PLATE FRUITS AND VEGETABLES Fruits can be fresh, canned, ...
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Full Text Available ... Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook ... Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart- ...
Full Text Available ... Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook ... Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart- ...
Full Text Available ... Your Plate It's simple and effective for both managing diabetes and losing weight. Creating your plate lets you still choose the foods you want, but changes the portion sizes so you are getting larger ...
Full Text Available ... Your Plate It's simple and effective for both managing diabetes and losing weight. Creating your plate lets ... Sleeve Custom jerseys for your Tour de Cure team benefits the cause. Ask the Experts: Learn to ...
Anderson, D L
1975-03-21
The concept of a stressed elastic lithospheric plate riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent plate boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that plate motions accelerate after great decoupling earthquakes and that most of the observed plate motions occur during short periods of time, separated by periods of relative quiescence.
Circular dichroism tensor of a triarylmethyl propeller in sodium chlorate crystals.
Bing, Yonghong; Selassie, David; Paradise, Ruthanne H; Isborn, Christine; Kramer, Nicholas; Sadilek, Martin; Kaminsky, Werner; Kahr, Bart
2010-06-02
In 1919, Perucca reported anomalous optical rotatory dispersion from chiral NaClO(3) crystals that were colored by having been grown from a solution containing an equilibrium racemic mixture of a triarylmethane dye (Perucca, E. Nuovo Cimento 1919, 18, 112-154). Perucca's chiroptical observations are apparently consistent with a resolution of the propeller-shaped dye molecules by NaClO(3) crystals. This implies that Perucca achieved the first enantioselective adsorption of a racemic mixture on an inorganic crystal, providing evidence of the resolution of a triarylmethyl propeller compound lacking bulky ortho substituents. Following the earlier report, NaClO(3) crystals dyed with aniline blue are described herein. The rich linear optical properties of (001), (110), and (111) sections of these mixed crystals are described via their absorbance spectra in polarized light as well as images related to linear dichroism, linear birefringence, circular dichroism, and anomalous circular extinction. The linear dichroism fixes the transition electric dipole moments in the aromatic plane with respect to the growth faces of the NaClO(3) cubes. Likewise, circular dichroism measurements of four orientations of aniline blue in NaClO(3) fix a bisignate tensor with respect to the crystal growth faces. Electronic transition moments and circular dichroism tensors were computed ab initio for aniline blue. These calculations, in conjunction with the crystal-optical properties, establish a consistent mixed-crystal model. The nature of the circular extinction depends upon the crystallographic direction along which the crystals are examined. Along 100, the crystals evidence circular dichroism. Along 110, the crystals evidence mainly anomalous circular extinction. These two properties, while measured by the differential transmission of left and right circularly polarized light, are easily distinguished in their transformation properties with respect to reorientations of the sample plates
Full Text Available ... Reset Plate Share Create Your Plate ! Share: Seven Simple Steps to Create Your Plate It's simple and effective for both managing diabetes and losing ... en.html Have Type 2 Diabetes? Our free program will help you live well. More from diabetes. ...
Obliquity along plate boundaries
Philippon, Mélody; Corti, Giacomo
2016-12-01
Most of the plate boundaries are activated obliquely with respect to the direction of far field stresses, as roughly only 8% of the plate boundaries total length shows a very low obliquity (ranging from 0 to 10°, sub-orthogonal to the plate displacement). The obliquity along plate boundaries is controlled by (i) lateral rheological variations within the lithosphere and (ii) consistency with the global plate circuit. Indeed, plate tectonics and magmatism drive rheological changes within the lithosphere and consequently influence strain localization. Geodynamical evolution controls large-scale mantle convection and plate formation, consumption, and re-organization, thus triggering plate kinematics variations, and the adjustment and re-orientation of far field stresses. These geological processes may thus result in plate boundaries that are not perpendicular but oblique to the direction of far field stresses. This paper reviews the global patterns of obliquity along plate boundaries. Using GPlate, we provide a statistical analysis of present-day obliquity along plate boundaries. Within this framework, by comparing natural examples and geological models, we discuss deformation patterns and kinematics recorded along oblique plate boundaries.
Circularly polarized lasing in chiral modulated semiconductor microcavity with GaAs quantum wells
Demenev, A A; Schneider, C; Brodbeck, S; Kamp, M; Höfling, S; Lobanov, S V; Weiss, T; Gippius, N A; Tikhodeev, S G
2016-01-01
We report the elliptically, close to circularly polarized lasing at $\\hbar\\omega = 1.473$ and 1.522 eV from an AlAs/AlGaAs Bragg microcavity with 12 GaAs quantum wells in the active region and chiral-etched upper distributed Bragg refractor under optical pump at room temperature. The advantage of using the chiral photonic crystal with a large contrast of dielectric permittivities is its giant optical activity, allowing to fabricate a very thin half-wave plate, with a thickness of the order of the emitted light wavelength, and to realize the monolithic control of circular polarization.
Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi
2009-08-26
Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
DEFF Research Database (Denmark)
Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin
2014-01-01
Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example......, plastics from WEEE is chosen as a Nordic case study. The project aims to propose a number of improvements for this value chain together with representatives from Nordic stakeholders. Based on the experiences made, a guide for other plastic value chains shall be developed....
Directory of Open Access Journals (Sweden)
Yutaka Tokiwa
2009-08-01
Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
Institute of Scientific and Technical Information of China (English)
2012-01-01
Journal of CHINA PLASTICS was authorized and approved by The State Committee of Science and Technology of China and The Bureau of News Press of China, and published by The China Plastics Processing Industry Association,Beijing Technology and Business University and The Institute of Plastics Processing and Application of Light Industry, distributed worldwide. Since its birth in 1987, CHINA PLASTICS has become a leading magazine in plastics industry in China, a national Chinese core journal and journal of Chinese scientific and technological article statistics. It is covered by CA.
Encryption using circular harmonic key
Jorge Enrique Rueda-Parada
2015-01-01
En este trabajo presento un estudio sobre la varianza a la rota ción de la llave del procesador de encriptación basado en la tr ansformada de Fourier. Determiné que la llave en coordenadas rectangulares pe rmite un nivel de tolerancia inferior a 0.2 grados de rotación de la llave en el proceso de decriptación. Entonces la solución es construir la llave en coordenadas polares, por medio de una expansión en armónicos circulares. De esta manera, el umbral de tolerancia a um...
Deterministic Circular Self Test Path
Institute of Scientific and Technical Information of China (English)
WEN Ke; HU Yu; LI Xiaowei
2007-01-01
Circular self test path (CSTP) is an attractive technique for testing digital integrated circuits(IC) in the nanometer era, because it can easily provide at-speed test with small test data volume and short test application time. However, CSTP cannot reliably attain high fault coverage because of difficulty of testing random-pattern-resistant faults. This paper presents a deterministic CSTP (DCSTP) structure that consists of a DCSTP chain and jumping logic, to attain high fault coverage with low area overhead. Experimental results on ISCAS'89 benchmarks show that 100% fault coverage can be obtained with low area overhead and CPU time, especially for large circuits.
Boxicity of Circular Arc Graphs
Bhowmick, Diptendu; Chandran, L. Sunil
2008-01-01
A $k$-dimensional box is the cartesian product $R_1 \\times R_2 \\times ... \\times R_k$ where each $R_i$ is a closed interval on the real line. The {\\it boxicity} of a graph $G$, denoted as $box(G)$, is the minimum integer $k$ such that $G$ can be represented as the intersection graph of a collection of $k$-dimensional boxes: that is two vertices are adjacent if and only if their corresponding boxes intersect. A circular arc graph is a graph that can be represented as the intersection graph of ...
Challenges in plastics recycling
DEFF Research Database (Denmark)
Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann
2015-01-01
Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
This paper reports a class of bulk metallic glass including Ce-, LaCe-, CaLi-, Yb-, and Sr-based metallic glasses, which are regarded as glassy metallic plastics because they combine some unique properties of both plastics and metallic alloys. These glassy metallic plastics have very low glass transition temperature (Tg~25oC to 150oC) and low Young’s modulus (~20 GPa to 35 GPa). Similar to glassy plastics, these metallic plastics show excellent plastic-like deformability on macro-, micro- and even nano-scale in their supercooled liquid range and can be processed, such as elongated, compressed, bent, and imprinted at low temperatures, in hot water for instance. Under ambient conditions, they display such metallic properties as high thermal and electric conductivities and excellent mechanical properties and other unique properties. The metallic plastics have potential applications and are also a model system for studying issues in glass physics.
Ruda, Mitchell C [Tucson, AZ; Greynolds, Alan W [Tucson, AZ; Stuhlinger, Tilman W [Tucson, AZ
2009-07-14
One or more disc-shaped angular shear plates each include a region thereon having a thickness that varies with a nonlinear function. For the case of two such shear plates, they are positioned in a facing relationship and rotated relative to each other. Light passing through the variable thickness regions in the angular plates is refracted. By properly timing the relative rotation of the plates and by the use of an appropriate polynomial function for the thickness of the shear plate, light passing therethrough can be focused at variable positions.
Energy Technology Data Exchange (ETDEWEB)
Gi-Man, Kim [Kum-Oh National Univ., Taegu (Korea, Republic of)
1994-12-31
Due to the prohibition law for using preon gas, many items in engineering field, specially heat exchanger, should be redesigned. The newly designed heat exchanger such a plate type heat exchanger is known to have a good efficiency in exchanging heat. From view of structures of a plate type heat exchanger, thin tube are used instead of circular pipe and the path of the fluid is developed for the high efficiency of the heat exchange by varying the array of tubes. The principal problem in the design of the plate heat exchanger is the potentiality of structural instabilities due to the fluid loading effect during operations. Excessive plate deflections would eventually result in permanent deformation or collapse which would cause an obstruction of the fluid flow in the narrow channels. In this study, a fluid-structural interaction model was developed to investigate analytically the static and dynamic instabilities that have been observed in flat plate heat exchanger. The model consist of two flat plates separated by water. The effects of the internal fluid in the channel was studied. As results, the natural frequency coefficients were investigated for the plate aspect ratios, channel heights, and boundary conditions. For the design criteria in plate type heat exchanger, the critical flow velocities which cause the responses of a plate were defined for divergence, resonance and flutter phenomena. (author). 25 refs. 2 tabs. 48 figs.
Attenuation in Superconducting Circular Waveguides
Directory of Open Access Journals (Sweden)
K. H. Yeap
2016-09-01
Full Text Available We present an analysis on wave propagation in superconducting circular waveguides. In order to account for the presence of quasiparticles in the intragap states of a superconductor, we employ the characteristic equation derived from the extended Mattis-Bardeen theory to compute the values of the complex conductivity. To calculate the attenuation in a circular waveguide, the tangential fields at the boundary of the wall are first matched with the electrical properties (which includes the complex conductivity of the wall material. The matching of fields with the electrical properties results in a set of transcendental equations which is able to accurately describe the propagation constant of the fields. Our results show that although the attenuation in the superconducting waveguide above cutoff (but below the gap frequency is finite, it is considerably lower than that in a normal waveguide. Above the gap frequency, however, the attenuation in the superconducting waveguide increases sharply. The attenuation eventually surpasses that in a normal waveguide. As frequency increases above the gap frequency, Cooper pairs break into quasiparticles. Hence, we attribute the sharp rise in attenuation to the increase in random collision of the quasiparticles with the lattice structure.
The Plastic Tension Field Method
DEFF Research Database (Denmark)
Hansen, Thomas
2005-01-01
. The emphasis is attached to the presentation of a design method based on the diagonal tension field theory. Also, how to determine the load-carrying capacity of a given steel plate girder with transverse web stiffeners, is briefly presented. The load-carrying capacity may be predicted by applying both...... method. The method is based on the theory of plasticity and is analogous to the so-called diagonal compression field method developed for reinforced concrete beams with transverse stirrups, which is adopted in the common European concrete code (Eurocode 2). Many other theories have been developed......, but the method presented differs from these theories by incorporating the strength of the transverse stiffeners and by the assumption that the tensile bands may pass the transverse stiffeners, which often is observed in tests. Other methods have only dealt with a single web field between two stiffeners...
Total positive curvature of circular DNA
DEFF Research Database (Denmark)
Bohr, Jakob; Olsen, Kasper Wibeck
2013-01-01
molecules, e.g., plasmids, it is shown to have implications for the total positive curvature integral. For small circular micro-DNAs it follows as a consequence of Fenchel's inequality that there must exist a minimum length for the circular plasmids to be double stranded. It also follows that all circular...... micro-DNAs longer than the minimum length must be concave, a result that is consistent with typical atomic force microscopy images of plasmids. Predictions for the total positive curvature of circular micro-DNAs are given as a function of length, and comparisons with circular DNAs from the literature......The properties of double-stranded DNA and other chiral molecules depend on the local geometry, i.e., on curvature and torsion, yet the paths of closed chain molecules are globally restricted by topology. When both of these characteristics are to be incorporated in the description of circular chain...
Recycling of plastic waste: Screening for brominated flame retardants (BFRs).
Pivnenko, K; Granby, K; Eriksson, E; Astrup, T F
2017-08-30
Flame retardants are chemicals vital for reducing risks of fire and preventing human casualties and property losses. Due to the abundance, low cost and high performance of bromine, brominated flame retardants (BFRs) have had a significant share of the market for years. Physical stability on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic product cycles and lead to increased exposure levels, e.g. through use of plastic packaging materials. To provide quantitative and qualitative data on presence of BFRs in plastics, we analysed bromophenols (tetrabromobisphenol A (TBBPA), dibromophenols (2,4- and 2,6-DBP) and 2,4,6-tribromophenol (2,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile butadiene styrene (ABS, up to 26,000,000ngTBBPA/g) and polystyrene (PS, up to 330,000ng∑HBCD/g). Abundancy in low concentrations of some BFRs in plastic samples suggested either unintended addition in plastic products or degradation of higher molecular weight BFRs. The presence of currently restricted flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling. Copyright © 2017. Published by Elsevier Ltd.
Thematic Minireview Series on Circular Proteins
Craik, David J.; Allewell, Norma M.
2012-01-01
Circular proteins have now been discovered in all kingdoms of life and are characterized by their exceptional stability and the diversity of their biological activities, primarily in the realm of host defense functions. This thematic minireview series provides an overview of the distribution, evolution, activities, and biological synthesis of circular proteins. It also reviews approaches that biological chemists are taking to develop synthetic methods for making circular proteins in the labor...
The correct mechanism of lithospheric plates movement
Ostrihansky, L.
2016-12-01
Imagination that lithospheric plates move above low-viscous seismic low-velocity zone contradicts to reality but alternating movement of variations of the Earth's rotation deform plastic mantle. Because these deformations never return to original position and solidified ascending magma in mid-ocean ridge prevents return, the lithospheric plates move plunging to mantle by their own weight and move westward pushed by force of tidal friction enlarged by alternating movement of heavy and large-volume mantle. This imagination has been proven by calculating azimuths of Moon and opposite tidal bulging in a moment of earthquake. They resulted occurring on local eastern horizon when earthquake was triggered and also calculated tidal torques in their maximums coincided with earthquakes. To distinguish these tidal properties the earthquakes in Hindu Kush in westward moving Eurasian plate were examined and also in northward moving Indian plate. LOD graph has shown that in Hindu Kush tidal friction triggers earthquake almost every day and large earthquakes are triggered in large positive LOD anomalies corresponding to deceleration. In the Indian plate the calculated maximum tidal torques corresponding to accelerations (LOD minimums) coincided with the greatest earthquakes: with the Great Sumatra 2004, largest Nepal earthquake 1934, large earthquake Nepal 2015 evoked by resonance effect and others.
Mathematical theory of elastic and elasto-plastic bodies an introduction
Necas, J
2013-01-01
The book acquaints the reader with the basic concepts and relations of elasticity and plasticity, and also with the contemporary state of the theory, covering such aspects as the nonlinear models of elasto-plastic bodies and of large deflections of plates, unilateral boundary value problems, variational principles, the finite element method, and so on.
Reaction-induced rheological weakening enables oceanic plate subduction
Hirauchi, Ken-Ichi; Fukushima, Kumi; Kido, Masanori; Muto, Jun; Okamoto, Atsushi
2016-08-01
Earth is the only terrestrial planet in our solar system where an oceanic plate subducts beneath an overriding plate. Although the initiation of plate subduction requires extremely weak boundaries between strong plates, the way in which oceanic mantle rheologically weakens remains unknown. Here we show that shear-enhanced hydration reactions contribute to the generation and maintenance of weak mantle shear zones at mid-lithospheric depths. High-pressure friction experiments on peridotite gouge reveal that in the presence of hydrothermal water, increasing strain and reactions lead to an order-of-magnitude reduction in strength. The rate of deformation is controlled by pressure-solution-accommodated frictional sliding on weak hydrous phyllosilicate (talc), providing a mechanism for the `cutoff' of the high peak strength at the brittle-plastic transition. Our findings suggest that infiltration of seawater into transform faults with long lengths and low slip rates is an important controlling factor on the initiation of plate tectonics on terrestrial planets.
Water wave scattering by a nearly circular cylinder submerged beneath an ice-cover
Chakraborty, Rumpa; Mandal, Birendra Nath
2015-03-01
Assuming linear theory, the two-dimensional problem of water wave scattering by a horizontal nearly circular cylinder submerged in infinitely deep water with an ice cover modeled as a thin-elastic plate floating on water, is investigated here. The cross-section of the nearly circular cylinder is taken as r= a( 1+δC( θ)), where a is the radius of the corresponding circular cross-section of the cylinder, δ is a measure of small departure of the cross-section of the cylinder from its circularity and C( θ) is the shape function. Using a simplified perturbation technique the problem is reduced to two independent boundary value problems up to first order in δ. The first one corresponds to water wave scattering by a circular cylinder submerged in water with an ice-cover, while the second problem describes wave radiation by a submerged circular cylinder and involves first order correction to the reflection and transmission coefficients. The corrections are obtained in terms of integrals involving the shape function. Assuming a general Fourier expansion of the shape function, these corrections are evaluated approximately. It is well known that normally incident wave trains experience no reflection by a circular cylinder submerged in infinitely deep water with an ice cover. It is shown here that the reflection coefficient also vanishes up to first order for some particular choice of the shape function representing a nearly circular cylinder. For these cases, full transmission occurs, only change is in its phase which is depicted graphically against the wave number in a number of figures and appropriate conclusions are drawn.
Water Wave Scattering by a Nearly Circular Cylinder Submerged Beneath an Ice-cover
Institute of Scientific and Technical Information of China (English)
Rumpa Chakraborty; Birendra Nath Mandal
2015-01-01
Assuming linear theory, the two-dimensional problem of water wave scattering by a horizontal nearly circular cylinder submerged in infinitely deep water with an ice cover modeled as a thin-elastic plate floating on water, is investigated here. The cross-section of the nearly circular cylinder is taken as r=a(1+δC(θ)), wherea is the radius of the corresponding circular cross-section of the cylinder,δ is a measure of small departure of the cross-section of the cylinder from its circularity andC(θ) is the shape function. Using a simplified perturbation technique the problem is reduced to two independent boundary value problems up to first order inδ. The first one corresponds to water wave scattering by a circular cylinder submerged in water with an ice-cover, while the second problem describes wave radiation by a submerged circular cylinder and involves first order correction to the reflection and transmission coefficients. The corrections are obtained in terms of integrals involving the shape function. Assuming a general Fourier expansion of the shape function, these corrections are evaluated approximately. It is well known that normally incident wave trains experience no reflection by a circular cylinder submerged in infinitely deep water with an ice cover. It is shown here that the reflection coefficient also vanishes up to first order for some particular choice of the shape function representing a nearly circular cylinder. For these cases, full transmission occurs, only change is in its phase which is depicted graphically against the wave number in a number of figures and appropriate conclusions are drawn.
DEFF Research Database (Denmark)
Nielsen, Kim Lau; Niordson, Christian Frithiof
2014-01-01
of a single plastic zone is analyzed to illustrate the agreement with earlier published results, whereafter examples of (ii) multiple plastic zone interaction, and (iii) elastic–plastic loading/unloading are presented. Here, the simple shear problem of an infinite slab constrained between rigid plates......–plastic loading/unloading and the interaction of multiple plastic zones, is proposed. The predicted model response is compared to the corresponding rate-dependent version of visco-plastic origin, and coinciding results are obtained in the limit of small strain-rate sensitivity. First, (i) the evolution...
Structural Changes of Surface Layers of Steel Plates in the Process of Explosive Welding
Bataev, I. A.; Bataev, A. A.; Mali, V. I.; Bataev, V. A.; Balaganskii, I. A.
2014-01-01
Structural changes developing in surface layers of plates from steel 20 in the process of explosive welding are studied with the help of light metallography and scanning and transmission electron microscopy. Mathematical simulation is used to compute the depth of the action of severe plastic deformation due to explosive welding of steel plates on the structure of their surface layers.
Čulin, Jelena; Bielić, Toni
2016-01-01
The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.
The Nonlinear Instability Modes of Dished Shallow Shells under Circular Line Loads
Directory of Open Access Journals (Sweden)
Liu Chang-Jiang
2011-01-01
Full Text Available This paper investigated the nonlinear stability problem of dished shallow shells under circular line loads. We derived the dimensionless governing differential equations of dished shallow shell under circular line loads according to the nonlinear theory of plates and shells and solved the governing differential equations by combing the free-parameter perturbation method (FPPM with spline function method (SFM to analyze the nonlinear instability modes of dished shallow shell under circular line loads. By analyzing the nonlinear instability modes and combining with concrete computational examples, we obtained the variation rules of the maximum deflection area of initial instability with different geometric parameters and loading action positions and discussed the relationship between the initial instability area and the maximum deflection area of initial instability. The results obtained from this paper provide some theoretical basis for engineering design and instability prediction and control of shallow-shell structures.
Modified Vertical Bearing Capacity for Circular Foundations in Sand Using Reduced Friction Angle
DEFF Research Database (Denmark)
Ibsen, Lars Bo; Barari, Amin; Larsen, Kim André
2012-01-01
Recently Bucket foundation as a large cylindrical structure that is open as the base and closed at the top, has attracted much attention in offshore projects. In order to present relationship between vertical bearing capacity of a bucket foundation relative to the corresponding capacity of a circ......Recently Bucket foundation as a large cylindrical structure that is open as the base and closed at the top, has attracted much attention in offshore projects. In order to present relationship between vertical bearing capacity of a bucket foundation relative to the corresponding capacity...... of a circular plate, several loading tests on small scale bucket foundations including the circular surface footings are performed at Aalborg University. In current research, the vertical bearing capacity of circular surface footings is investigated using reduced friction angle. It is also presented a linear...
DEFF Research Database (Denmark)
Islam, Aminul
The purpose of this document is to summarize the information about the laser welding of plastic. Laser welding is a matured process nevertheless laser welding of micro dimensional plastic parts is still a big challenge. This report collects the latest information about the laser welding of plasti...... as a knowledge handbook for laser welding of plastic components. This document should provide the information for all aspects of plastic laser welding and help the design engineers to take all critical issues into consideration from the very beginning of the design phase....
Halden, Rolf U
2010-01-01
By 2010, the worldwide annual production of plastics will surpass 300 million tons. Plastics are indispensable materials in modern society, and many products manufactured from plastics are a boon to public health (e.g., disposable syringes, intravenous bags). However, plastics also pose health risks. Of principal concern are endocrine-disrupting properties, as triggered for example by bisphenol A and di-(2-ethylhexyl) phthalate (DEHP). Opinions on the safety of plastics vary widely, and despite more than five decades of research, scientific consensus on product safety is still elusive. This literature review summarizes information from more than 120 peer-reviewed publications on health effects of plastics and plasticizers in lab animals and humans. It examines problematic exposures of susceptible populations and also briefly summarizes adverse environmental impacts from plastic pollution. Ongoing efforts to steer human society toward resource conservation and sustainable consumption are discussed, including the concept of the 5 Rs--i.e., reduce, reuse, recycle, rethink, restrain--for minimizing pre- and postnatal exposures to potentially harmful components of plastics.
Synaptic Plasticity and Nociception
Institute of Scientific and Technical Information of China (English)
ChenJianguo
2004-01-01
Synaptic plasticity is one of the fields that progresses rapidly and has a lot of success in neuroscience. The two major types of synaptie plasticity: long-term potentiation ( LTP and long-term depression (LTD are thought to be the cellular mochanisms of learning and memory. Recently, accumulating evidence suggests that, besides serving as a cellular model for learning and memory, the synaptic plasticity involves in other physiological or pathophysiological processes, such as the perception of pain and the regulation of cardiovascular system. This minireview will focus on the relationship between synaptic plasticity and nociception.
Nettesheim, Matthias; Ehlers, Todd; Whipp, David
2016-04-01
Syntaxes are short, convex bends in the otherwise slightly concave plate boundaries of subduction zones. These regions are of scientific interest because some syntaxes (e.g., the Himalaya or St. Elias region in Alaska) exhibit exceptionally rapid, focused rock uplift. These areas have led to a hypothesized connection between erosional and tectonic processes (top-down control), but have so far neglected the unique 3D geometry of the subducting plates at these locations. In this study, we contribute to this discussion by exploring the idea that subduction geometry may be sufficient to trigger focused tectonic uplift in the overriding plate (a bottom-up control). For this, we use a fully coupled 3D thermomechanical model that includes thermochronometric age prediction. The downgoing plate is approximated as spherical indenter of high rigidity, whereas both viscous and visco-plastic material properties are used to model deformation in the overriding plate. We also consider the influence of the curvature of the subduction zone and the ratio of subduction velocity to subduction zone advance. We evaluate these models with respect to their effect on the upper plate exhumation rates and localization. Results indicate that increasing curvature of the indenter and a stronger upper crust lead to more focused tectonic uplift, whereas slab advance causes the uplift focus to migrate and thus may hinder the emergence of a positive feedback.
Production of the Large-area Plastic Scintillator for Beta-ray Detection using Epoxy Resin
Energy Technology Data Exchange (ETDEWEB)
Nam, Jong Soo; Choi, Yong Seok; Hong, Sang Bum; Seo, Bum Kyung; Moon, Jei Kwon; Choi, Jong Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2016-10-15
In this study, we prepared a plastic scintillator whose manufacturing process is simple and can be freely shaped. A thin plate of the plastic scintillator was manufactured using epoxy resin as a polymer. The plastic scintillator was made by mixing epoxy resin and organic scintillators under various conditions. The optimal mixture ratio to prepare the plastic scintillator was derived from the above results. Using the derived results, we made the large-area plastic scintillator which can quickly measure the contamination site and evaluated characteristics of the large-area plastic scintillator in the laboratory. A thin plate of a plastic scintillator with a simple preparation process can be freely shaped using epoxy resin and organic scintillators such as PPO and POPOP. PPO emits scintillation of light in the ultraviolet range, and POPOP is a wave shifter for moving the wavelength responsible for the PMT. The mixture ratio of PPO and POPOP was determined using their emission spectra. The optimal weight percentage of PPO and POPOP in an organic scintillator was determined to be 0.2 wt%:0.01 wt%. Based on the above results, the large-area plastic scintillator of the window size of a typical pancake-type αβ surface contamination counter was prepared. We want to evaluate the characteristics of the large-area plastic scintillator. However, there were the difficulties in evaluating characteristics of the large-area plastic scintillator. The cross-sectional area of the large-area plastic scintillator is significantly different to PMT.
Accuracy of distal radius positioning using an anatomical plate.
Vroemen, Joy C; Dobbe, Johannes G G; Sierevelt, Inger N; Strackee, Simon D; Streekstra, Geert J
2013-04-01
Over the past decade, several anatomical plates have been introduced to improve the result of open reduction and internal fixation of the distal radius. Using 3-dimensional imaging techniques, the authors studied the accuracy and reproducibility of distal radius positioning using anatomical plates.Distal radius fractures and the correction of these fractures were simulated with plastic bone models of radii. The authors simulated a defect by removing an arbitrary wedge shape from the artificial radii. Two surgeons corrected these fractures by placing 2 anatomical plate types according to the plate manufacturers' instructions. The residual positioning errors of the distal segment in relation to the unaffected radii were determined using 3-dimensional imaging and were compared with naturally occurring bilateral radius differences in healthy individuals. In many cases, positioning does not agree with differences based on bilateral asymmetry in healthy patients.This study indicated the accuracy of anatomical plates. Positioning an anatomical plate may lead to considerable residual errors in individual patients. Volar distal radius plate shapes differ among plate manufacturers. Therefore, one plate may perform better than another in an individual.
Generalized Fibonacci zone plates
Ke, Jie; Zhu, Jianqiang
2015-01-01
We propose a family of zone plates which are produced by the generalized Fibonacci sequences and their axial focusing properties are analyzed in detail. Compared with traditional Fresnel zone plates, the generalized Fibonacci zone plates present two axial foci with equal intensity. Besides, we propose an approach to adjust the axial locations of the two foci by means of different optical path difference, and further give the deterministic ratio of the two focal distances which attributes to their own generalized Fibonacci sequences. The generalized Fibonacci zone plates may allow for new applications in micro and nanophotonics.
Directory of Open Access Journals (Sweden)
Kiran D. Mali
2013-01-01
Full Text Available This paper is concerned with a vibration analysis of perforated rectangular plates with rectangular perforation pattern of circular holes. The study is particularly useful in the understanding of the vibration of sound absorbing screens, head plates, end covers, or supports for tube bundles typically including tube sheets and support plates used in the mechanical devices. An energy method is developed to obtain analytical frequencies of the perforated plates with clamped edge, support conditions. Perforated plate is considered as plate with uniformly distributed mass. Holes are considered as concentrated negative masses. The analytical procedure using the Galerkin method is adopted. The deflected surface of the plate is approximated by the cosine series which satisfies the boundary conditions. Finite element method (FEM results have been used to illustrate the validity of the analytical model. The comparisons show that the analytical model predicts natural frequencies reasonably well for holes of small size.
77 FR 42077 - Environmental Justice: Final Circular
2012-07-17
.... However, recipients may use a more inclusive definition of low-income, e.g., 150% of poverty level, or... relevant definitions. FTA's EJ Circular builds on the DOT Order, and provides further guidance for... illustrations have been added. FTA reviewed all of the definitions and terms used in the Circular to ensure that...
Exon circularization in mammalian nuclear extracts.
Pasman, Z; Been, M D; Garcia-Blanco, M A
1996-06-01
Correct ligation of exons in pre-mRNA splicing requires splice site juxtaposition (splice site pairing), usually involving a 5' splice site and a downstream 3' splice site. Splicing of a 5' splice site to an upstream 3' splice site, however, is predicted to result in a circular RNA. This mode of splice site pairing across the axon has been hypothesized to account for rare RNAs containing scrambled exons (Nigro JM et al., 1991, Celt 64:607-613; Cocquerelle C et al., 1992, EMBO J 11:1 095-1098). Additionally, this mode of splice site pairing has been postulated to explain the formation of SRY circular transcripts in mouse testis (Capel B et al., 1993, Celt 73:1019- 1030). Here we show that splice site pairing across the exon can result in exon circularization in vitro. These results indicate that spliceosome-mediated axon circularization indeed can account for the formation of scrambled exons and circular RNAs. Exon circularization efficiency decreased dramatically as the length of the exon was increased from 95 nt to 274 nt. Circularization of this longer exon was restored, however, when intronic complementary sequences were included in the RNA substrate. These complementary sequences could form a stem that served to bring the splice sites into proximity and thereby promote splice site pairing. Therefore, the splicing of this structured RNA recapitulated SRY-like exon circularization in vitro.
Nanofocusing in circular sector-like nanoantennas
DEFF Research Database (Denmark)
Zenin, Volodymyr; Pors, Anders Lambertus; Han, Zhanghua;
2014-01-01
a concentric circular line of phase contrast, demonstrating resonant excitation of a standing wave of counter-propagating surface plasmons, travelling between a tip and opposite circular edge of the antenna. Transmission spectra obtained in the range 900 - 2100 nm are in good agreement with numerical...
Foods advertised in US weekly supermarket sales circulars over one year: a content analysis.
Jahns, Lisa; Payne, Collin R; Whigham, Leah D; Johnson, LuAnn K; Scheett, Angela J; Hoverson, Bonita S; Kranz, Sibylle
2014-09-23
The nutritional content of Americans' shopping carts is suboptimal despite federal dietary guidance, in this case, the MyPlate consumer icon which displays desired proportions of vegetables, fruits, dairy, grains and protein foods for consumption. Consumers mention print advertising-such as weekly sales circulars-frequently as influencing their grocery shopping decisions. To examine and describe the relative proportions of advertised foods aggregated into the MyPlate food grouping system, a content analysis of 9 209 foods advertised in 52 weekly supermarket newspaper sales inserts in 2009 from a local grocery chain was conducted in a Midwestern community. Overall, the protein foods group was most often represented in sales circulars (25% of total items), followed by grains (18%); dairy (10%); vegetables (8%) and fruits (7%). Less than 3% of sales advertisements were for dark green and red & orange vegetables. Over twice as much whole fruit versus 100% fruit juice was advertised (70% vs. 30%, respectively; P < 0.001). Significantly fewer protein foods and more grains than expected were advertised in the fall, and slightly more dark green vegetables were advertised in winter and spring than in summer and fall (P = 0.05). The average American diet, including underconsumption of fruits and vegetables but overconsumption of protein foods, was reflected in the relative frequency of food groups advertised in weekly sales circulars. Modifying sales circulars to represent healthier food groups may preserve retail profits (considering these groups' higher profit margin) while promoting adherence to federal dietary guidance.
CIRCULAR ECONOMY IN ROMANIA WITHIN EUROPEAN CONTEXT
Directory of Open Access Journals (Sweden)
Cornelia Marcela Danu
2015-07-01
Full Text Available In the present paper we have approached some conceptual and coordinated marks of the societal reality connected to the circular economy. Generated by „the limits of certainty” regarding the future of the world business, the operationalization of the circular economy has become a part of the EU strategies and started the various stages of implementation as an active process in all countries. We have highlighted the opportunities and the risks related to the circular economy, the European dimension and, in particular, the Romanian one of this process, the role of the triad: consumer-company-natural environment, while implementing the circular economy. Circular economy is both a new approach of the societal life, based on changing the mentalities of the individuals having the role of decision makers at the company level and public administration and the decision makers – consumers, as well as a policy meant to be made operational across all entities: governmental, entrepreneurial, individually – human.
Circular motion in NUT space-time
Jefremov, Paul
2016-01-01
We consider circular motion in the NUT (Newman-Unti-Tamburino) space-time. Among other things, we determine the location of circular time-like geodesic orbits, in particular of the innermost stable circular orbit (ISCO) and of the marginally bound circular orbit. Moreover, we discuss the von Zeipel cylinders with respect to the stationary observers and with respect to the Zero Angular Momentum Observers (ZAMOs). We also investigate the relation of von Zeipel cylinders to inertial forces, in particular in the ultra-relativistic limit. Finally, we generalise the construction of thick accretion tori ("Polish doughnuts") which are well known on the Schwarzschild or Kerr background to the case of the NUT metric. We argue that, in principle, a NUT source could be distinguished from a Schwarzschild or Kerr source by observing the features of circular matter flows in its neighbourhood.
Gauge-Invariant Formulation of Circular Dichroism.
Raimbault, Nathaniel; de Boeij, Paul L; Romaniello, Pina; Berger, J A
2016-07-12
Standard formulations of magnetic response properties, such as circular dichroism spectra, are plagued by gauge dependencies, which can lead to unphysical results. In this work, we present a general gauge-invariant and numerically efficient approach for the calculation of circular dichroism spectra from the current density. First we show that in this formulation the optical rotation tensor, the response function from which circular dichroism spectra can be obtained, is independent of the origin of the coordinate system. We then demonstrate that its trace is independent of the gauge origin of the vector potential. We also show how gauge invariance can be retained in practical calculations with finite basis sets. As an example, we explain how our method can be applied to time-dependent current-density-functional theory. Finally, we report gauge-invariant circular dichroism spectra obtained using the adiabatic local-density approximation. The circular dichroism spectra we thus obtain are in good agreement with experiment.
Directory of Open Access Journals (Sweden)
S. M. Marandi
2008-01-01
Full Text Available This study seeks to widen the pool of knowledge on the use and characteristics of geosynthetics, specifically in the area of circular foundations supported by geosynthetic reinforced sand. The main objective of the work was to increase the awareness of circular foundation systems and thus increase the accuracy of current laboratory methods. Also, compare the results with that of previous papers on the subject and to provide new model curves to estimate the bearing capacity of circular foundations. In this respect, the foundation and the soil underneath was modeled using four nots isoparameters finite element aid, while, for geogrid reinforcement, the four nots one-dimentional finite element model was used. The sand behavior was based on demolition elasto-plastic drucker-prager criteria and for the reinforcement the linear criteria was used. The paper investigates the effects of the reinforcement placing properties, soil properties, reinforcement properties, and the geometric properties of circular foundations. The results showed that; the bearing capacity ratio at a settlement level for geogrid reinforced sand is effected considerably by parameters such as: reinforcement placement, reinforcement layers, reinforcement strength, geometric properties of circular foundations, and effects of using granular soils. Based on the results achieved, a number of design curves have been developed to assist with the estimation (design of field bearing capacity of shallow foundations supported by geogrid reinforced soil. Keeping in mind the settlement limitations in real space, the curves have been developed for normal settlement levels up to a settlement ratio of 2.5%.
Description of the M-integral in an elastic plastic material
Tao, Huiyu; Gao, Cheng; Xu, Jinyong; Tang, Yan; Cai, Dayong; Huang, Ranran
2017-01-01
By use of finite element analysis method of elastic-plasticity, a calculation of M-integral for 7075 aluminum alloy plate containing different configuration defects was conducted. The effect of plastic energy on path independence of the M-integral is discussed, The variation of M-integral of the holes before and after coalescence under tension loading is studied. Analysis result indicates that M-integral will be path dependent when the plastic zone is passed through by the selected integration contours. There is a jump of the M-integral when coalescence of the holes in a plate occurs. The value of the M-integral is always configuration dependent.
Requalification analysis of a circular composite slab for seismic load
Energy Technology Data Exchange (ETDEWEB)
Srinivasan, M.G.; Kot, C.A.
1992-11-01
The circular roof slab of an existing facility was analyzed to requalify the structure for supporting a significant seismic load that it was not originally designed for. The slab has a clear span of 66 ft and consists of a 48 in thick reinforced concrete member and a steel liner plate. Besides a number of smaller penetrations, the slab contains two significant cutouts: a 9 ft square opening and a 3 ft dia hole. The issues that complicated the analysis of this non-typical structure, i.e., composite action and nonlinear stiffness of reinforced concrete (R. C.) sections, are discussed. It was possible to circumvent the difficulties by making conservative and simplifying assumptions. If codes incorporate guidelines on practical methods for dynamic analysis of R. C. structures, some of the unneeded conservatism could be eliminated in future designs.
Some comments on the electrostatic forces between circular electrodes
Maccarrone, F
2016-01-01
We study the force between two circular electrodes in different configurations. A formula analogous to Kelvin's formula for the spheres is given in the case of equal disks held at the same potential and when one plate is earthed. An expression for the force at short distance between two arbitrarily charged disks is found: the generic case shows a logarithmic repulsive force, also for disks carrying charges of opposite sign. Some numerical computations support the results. A classification for the possible behaviors of the force is proposed on the basis of a decomposition of the capacitance matrix. It is shown that the forces depend strongly on the dimensionality of the contact zone between the conductors. The analysis is supported by a numerical computation carried for the case of two disks of different radii.
Study on the breakup length of circular impinging jet
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Circular impinging jet, which is widely used in accelerated control cooling (ACC) equipment to accelerate the cooling of hot rolled plates, is subject to breakup, and may result in undesirable cooling effect. Therefore, the jet breakup should be avoided as possible in industrial production. The objective of this study is to find the relation of the processing parameters of the ACC equipment versus the breakup length of jet with weaker turbulence. To obtain quantitative findings, not only relative experimental study but also numerical simulation was carried out. For a weaker turbulent water jet, the breakup length increases with the increase of jet diameter, as well as with the jet velocity; jet diameter has a significant effect on the breakup length for a certain flow rate when compared with jet velocity; finally a suggested correlation of the jet breakup length versus jet Weber number is presented in this study.
Institute of Scientific and Technical Information of China (English)
Maya Reid
2012-01-01
The halos that span South Africa's coastline are anything but angelic. Fanning out around four major urban centers-Cape Town, Port Elizabeth, East London and Durban-they are made up of innumerable bits and pieces of plastic. As a form of pollution, their shelflife is unfathomable. Plastic is essentially chemically inactive. It's designed to never break down.
Shimao, M
2001-06-01
Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. Recent work has included studies of the distribution of synthetic polymer-degrading microorganisms in the environment, the isolation of new microorganisms for biodegradation, the discovery of new degradation enzymes, and the cloning of genes for synthetic polymer-degrading enzymes.
DESIGNERS’ KNOWLEDGE IN PLASTICS
DEFF Research Database (Denmark)
Eriksen, Kaare
2013-01-01
The Industrial designers’ knowledge in plastics materials and manufacturing principles of polymer products is very important for the innovative strength of the industry, according to a group of Danish plastics manufacturers, design students and practicing industrial designers. These three groups...... answered the first Danish national survey, PD13[1], investigating the importance of industrial designers’ knowledge in plastics and the collaboration between designers and the polymer industry. The plastics industry and the industrial designers collaborate well, but both groups frequently experience...... that the designers’ lack of knowledge concerning polymer materials and manufacturing methods can be problematic or annoying, and design students from most Danish design universities express the need for more contact with the industry and more competencies and tools to handle even simple topics when designing plastic...
Consciousness and neural plasticity
DEFF Research Database (Denmark)
In contemporary consciousness studies the phenomenon of neural plasticity has received little attention despite the fact that neural plasticity is of still increased interest in neuroscience. We will, however, argue that neural plasticity could be of great importance to consciousness studies....... If consciousness is related to neural processes it seems, at least prima facie, that the ability of the neural structures to change should be reflected in a theory of this relationship "Neural plasticity" refers to the fact that the brain can change due to its own activity. The brain is not static but rather...... the relation between consciousness and brain functions. If consciousness is connected to specific brain structures (as a function or in identity) what happens to consciousness when those specific underlying structures change? It is therefore possible that the understanding and theories of neural plasticity can...
Fontes, Kris
2009-01-01
In the December 1997 issue of "SchoolArts" is a lesson titled "Blue Willow Story Plates" by Susan Striker. In this article, the author shares how she used this lesson with her middle-school students many times over the years. Here, she describes a Blue Willow plate painting project that her students made.
Full Text Available ... In Memory In Honor Become a Member En Español Type 1 Type 2 About Us Online Community ... Page Text Size: A A A Listen En Español Create Your Plate Create Your Plate is a ...
Full Text Available ... Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal Planning ... Planning Meals Diabetes Meal Plans and a Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets ...
Design consideration for design a flat and ring plastics part using Solidworks software
Amran, M. A. M.; Faizal, K. M.; Salleh, M. S.; Sulaiman, M. A.; Mohamad, E.
2015-12-01
Various considerations on design of plastic injection moulded parts were applied in initial stage to prevent any defects of end products. Therefore, the objective of this project is to design the plastic injection moulded part by taking consideration on several factors such as draft angle, corner radius and location of gate. In this project, flat plastic part, ring plastic part, core inserts for flat and ring plastic part were designed using SolidWorks software. The plastic part was drawn in sketching mode then the 3D modeling of solid part was generated using various commands. Considerations of plastic part such as draft angle and corner radius with location of gate was considered in the design stage. Finally, it was successfully designed the two plastic parts with their respectively insert by using SolidWorks software. The flat plastic part and ring plastic part were designed for the purpose for future researches for study the weld lines, meld lines, air trapped and geometrical size of the product. Thus, by designing the flat plastic part and ring plastic part having core insert on each part, the completed mould design of two plate mould can be considered. This is because, plastic injection parts are needed to be designed properly in order to neglect any defect when the mould was made.
Process engineering in circular economy
Institute of Scientific and Technical Information of China (English)
Lothar Reh
2013-01-01
Driven by increasing global population and by growing demand for individual wealth,the consumption of energy and raw materials as well as the steadily growing CO2 concentration in atmosphere pose great challenges to process engineering.This complex multi-scale discipline deals with the transformation of mass by energy to manifold products in different industrial fields under economical and ecological sustainable conditions.In growing circular economy,process engineering increasingly plays an important role in recovering valuable components from very diffuse material flows leaving the user stocks following widely variable time periods of use.As well it is engaged in thermal recovery of energy therefrom and in environmentally safe disposal of residual solid wastes whose recovery economically is not feasible.An efficient recovery of materials and energy following the laws of entropy is a must.A complex network of mass,energy,transportation and information flows has to be regarded with growing traded quantities of used goods even on global level.Important constraints in time,however,exist for a necessary realization of innovative new processes and communal mobility and industrial infrastructure on medium and large scale.Based on reasonable long term and highly reliable statistics from industrial organizations representing steel and paper industry,some limits and trends of possible developments in processing of those industries with long recycling experience will be discussed.
Encryption using circular harmonic key
Directory of Open Access Journals (Sweden)
Jorge Enrique Rueda-Parada
2015-01-01
Full Text Available En este trabajo presento un estudio sobre la varianza a la rota ción de la llave del procesador de encriptación basado en la tr ansformada de Fourier. Determiné que la llave en coordenadas rectangulares pe rmite un nivel de tolerancia inferior a 0.2 grados de rotación de la llave en el proceso de decriptación. Entonces la solución es construir la llave en coordenadas polares, por medio de una expansión en armónicos circulares. De esta manera, el umbral de tolerancia a umenta aproximadamente hasta 40 grados de rotación de la llave en el proceso de decriptación. Esta solución es un valor agregado par a el procesador de encriptación óptico. He desarrollado una her ramienta computacional para las simulaciones y resultados obtenidos en e ste estudio.
Apyan, A; Badelek, B; Ballestrero, S; Biino, C; Birol, I; Cenci, P; Connell, S H; Eichblatt, S; Fonseca, T; Freund, A; Gorini, B; Groess, R; Ispirian, K; Ketel, T; Kononets, Yu V; López, A; Mangiarotti, A; Sellschop, J P Friedel; Shieh, M; Sona, P; Strakhovenko, V M; Uggerhøj, Erik; Uggerhøj, U; Van Rens, B; Velasco, M; Vilakazi, Z Z; Wessely, O; Ünel, G; Kononets, Yu.V.
2003-01-01
We present the first experimental results on the use of a thick aligned Si crystal acting as a quarter wave plate to induce a degree of circular polarisation in a high energy linearly polarised photon beam. The linearly polarised photon beam is produced from coherent bremsstrahlung radiation by 178 GeV unpolarised electrons incident on an aligned Si crystal, acting as a radiator. The linear polarisation of the photon beam is characterised by measuring the asymmetry in electron-positron pair production in a Ge crystal, for different crystal orientations. The Ge crystal therefore acts as an analyser. The birefringence phenomenon, which converts the linear polarisation to circular polarisation, is observed by letting the linearly polarised photons beam pass through a thick Si quarter wave plate crystal, and then measuring the asymmetry in electron-positron pair production again for a selection of relative angles between the crystallographic planes of the radiator, analyser and quarter wave plate. The systematics...
Polarimetric investigation of materials with both linear and circular anisotropy
DEFF Research Database (Denmark)
Naydenova, I.; Nikolova, L.; Todorov, T.;
1997-01-01
We investigate light propagation through materials with both linear and circular anisotropy and find the relation of the amplitude and polarization transfer functions to the four anisotropic characteristics: linear circular birefringence, and linear and circular dichroism. We determine these four...
Uniformity Tests in Circular Data: Review
Directory of Open Access Journals (Sweden)
Ismet DOGAN
2015-10-01
Full Text Available Circular data are a large class of directional data, which are interest in many fields. Examples include phenomena that are periodic in time, including those dependent on hours of the day (hospital visits, times of birth, etc. or days of the year (unemployment or sales variations. The elementary but also fundamental property of circular data is that the beginning and end of the scale coincide: for example, 0° = 360°. An immediate implication is that the arithmetic mean is likely to be a poor summary: the mean of 1° and 359° cannot sensibly be 180°. The solution is use the vector mean direction as circular mean. The statistical analysis of angular or circular data differs from the analysis of linear data. Unlike linear distributions, which are often two-tailed and infinite, circular distributions exhibit finite closure because a circular data set comes back on itself, and therefore, 0° and 360° are actually the same point on a circle. Circular statistics is concerned mainly with observations which are unit vectors in the plane. Thus the sample space is typically a circle or a sphere, so that standart methods for analysing univariate or multivariate measurement data can?t be used. Special circular methods are required take into account the structure of these sample spaces. In most circular statistical analyses, the null hypothesis is a uniform distribution in which all directions occur with equal probability. In this study, eight different testing methods improved for uniformity in angular data have been introduced and these methods were compared with each other by using the information obtained from the literature.
Plastic Deformation of Metal Tubes Subjected to Lateral Blast Loads
Directory of Open Access Journals (Sweden)
Kejian Song
2014-01-01
Full Text Available When subjected to the dynamic load, the behavior of the structures is complex and makes it difficult to describe the process of the deformation. In the paper, an analytical model is presented to analyze the plastic deformation of the steel circular tubes. The aim of the research is to calculate the deflection and the deformation angle of the tubes. A series of assumptions are made to achieve the objective. During the research, we build a mathematical model for simply supported thin-walled metal tubes with finite length. At a specified distance above the tube, a TNT charge explodes and generates a plastic shock wave. The wave can be seen as uniformly distributed over the upper semicircle of the cross-section. The simplified Tresca yield domain can be used to describe the plastic flow of the circular tube. The yield domain together with the plastic flow law and other assumptions can finally lead to the solving of the deflection. In the end, tubes with different dimensions subjected to blast wave induced by the TNT charge are observed in experiments. Comparison shows that the numerical results agree well with experiment observations.
Gordon, Richard G.
Diffuse plate boundaries occur in both oceanic and continental lithosphere and cover ≈ 15% of Earth's solid surface. The fastest plate speeds accommodated across diffuse oceanic plate boundaries are ≈ 15 mm/yr. The smallest strain rates averaged across narrow plate boundaries are at least 102 times larger than the largest strain rates across diffuse oceanic plate boundaries and at least 102 times larger than those across stable plate interiors. The effective viscosity (ηeff) of the lithosphere is estimated from the ratio of vertically averaged shear stresses to strain rates for three tectonic settings: (i) oceanic transform fault zones, for which ηeff = 3 ×1016 to 5×1019 Pa s, comparable to estimates for the asthenosphere, (ii) diffuse oceanic plate boundaries, for which ηeff = 1×1023 to 6×l023 Pa s, ≈ 10 times larger than for diffuse continental plate boundaries, and (iii) stable plate interiors, for which ηeff = 1x1024 to 2×1027 Pa s. The rheology of oceanic lithosphere over times longer than earthquake cycles is modeled as a plastic layer overlying a layer that deforms by creeping flow [Martinod and Davy, 1992]. Oceanic lithosphere deforms when the yield strength of the upper lithosphere is exceeded. The vertically averaged rheology of deforming oceanic lithosphere can be approximated by a power-law fluid for which ɛ. ∝ (τs)n where ɛ. is the rate of shear strain and τs is the shear stress. If the ratio of the yield strength of the upper lithosphere to the force required to deform the lower lithosphere at a strain rate of 10-16 s-1 is varied from 10-2 to 102 , the calculated value of n varies from ≈3 to ≈300. The map-view aspect ratio of a deforming zone in a thin sheet of power-law fluid is proportional to n-½ [England et al., 1985]. A profile of displacement versus distance inferred from a seismic profile across the Central Indian Basin (India-Capricorn diffuse oceanic plate boundary), where the lithosphere is about 60-Myr old
University Students Alternative Conceptions On Circular Motion
Directory of Open Access Journals (Sweden)
Ian Phil Canlas
2015-08-01
Full Text Available This study attempted to find out university students alternative conceptions on circular motion. An 18-item researcher-compiled and content-validated questionnaire was administered to twenty-six 26 students taking up a program in Bachelor in Secondary Education-Physical Science in their second year enrolled in a course on mechanics. Results revealed that majority of the students possess alternative conceptions on circular motion specifically along velocity acceleration and force. Moreover results showed the inconsistencies in the students understanding of circular motion concepts.
Circular polarization memory in polydisperse scattering media
Macdonald, Callum M; Meglinski, Igor
2015-01-01
We investigate the survival of circularly polarized light in random scattering media. The surprising persistence of this form of polarization has a known dependence on the size and refractive index of scattering particles, however a general description regarding polydisperse media is lacking. Through analysis of Mie theory, we present a means of calculating the magnitude of circular polarization memory in complex media, with total generality in the distribution of particle sizes and refractive indices. Quantification of this memory effect enables an alternate pathway towards recovering particle size distribution, based on measurements of diffusing circularly polarized light.
Pixelated neutron image plates
Schlapp, M.; Conrad, H.; von Seggern, H.
2004-09-01
Neutron image plates (NIPs) have found widespread application as neutron detectors for single-crystal and powder diffraction, small-angle scattering and tomography. After neutron exposure, the image plate can be read out by scanning with a laser. Commercially available NIPs consist of a powder mixture of BaFBr : Eu2+ and Gd2O3 dispersed in a polymer matrix and supported by a flexible polymer sheet. Since BaFBr : Eu2+ is an excellent x-ray storage phosphor, these NIPs are particularly sensitive to ggr-radiation, which is always present as a background radiation in neutron experiments. In this work we present results on NIPs consisting of KCl : Eu2+ and LiF that were fabricated into ceramic image plates in which the alkali halides act as a self-supporting matrix without the necessity for using a polymeric binder. An advantage of this type of NIP is the significantly reduced ggr-sensitivity. However, the much lower neutron absorption cross section of LiF compared with Gd2O3 demands a thicker image plate for obtaining comparable neutron absorption. The greater thickness of the NIP inevitably leads to a loss in spatial resolution of the image plate. However, this reduction in resolution can be restricted by a novel image plate concept in which a ceramic structure with square cells (referred to as a 'honeycomb') is embedded in the NIP, resulting in a pixelated image plate. In such a NIP the read-out light is confined to the particular illuminated pixel, decoupling the spatial resolution from the optical properties of the image plate material and morphology. In this work, a comparison of experimentally determined and simulated spatial resolutions of pixelated and unstructured image plates for a fixed read-out laser intensity is presented, as well as simulations of the properties of these NIPs at higher laser powers.
Plate removal following orthognathic surgery.
Little, Mhairi; Langford, Richard Julian; Bhanji, Adam; Farr, David
2015-11-01
The objectives of this study are to determine the removal rates of orthognathic plates used during orthognathic surgery at James Cook University Hospital and describe the reasons for plate removal. 202 consecutive orthognathic cases were identified between July 2004 and July 2012. Demographics and procedure details were collected for these patients. Patients from this group who returned to theatre for plate removal between July 2004 and November 2012 were identified and their notes were analysed for data including reason for plate removal, age, smoking status, sex and time to plate removal. 3.2% of plates were removed with proportionally more plates removed from the mandible than the maxilla. 10.4% of patients required removal of one or more plate. Most plates were removed within the first post-operative year. The commonest reasons for plate removal were plate exposure and infection. The plate removal rates in our study are comparable to those seen in the literature.
Computer simulation of viscous fingering in a lifting Hele-Shaw cell with grooved plates
Indian Academy of Sciences (India)
Sujata Tarafdar; Soma Nag; Tapati Dutta; Suparna Sinha
2009-10-01
We simulate viscous fingering generated by separating two plates with a constant force, in a lifting Hele-Shaw cell. Variation in the patterns for different fluid viscosity and lifting force is studied. Viscous fingering is strongly affected by anisotropy. We report a computer simulation study of fingering patterns, where circular or square grooves are etched on to the lower plate. Results are compared with experiments.
The Dugdale solution for two unequal straight cracks weakening in an inﬁnite plate
Indian Academy of Sciences (India)
R R Bhargava; Shehzad Hasan
2010-02-01
A crack arrest model is proposed for an inﬁnite elastic perfectly-plastic plate weakened by two unequal, quasi-static, collinear straight cracks. The Dugdale model solution is obtained for the above problem when the developed plastic zones are subjected to normal cohesive quadratically varying yield point stress. Employing complex variable technique and the superposition principle the desired solution is obtained. A qualitative study of load required to arrest the plastic zones opening with respect to affecting parameters viz. inter-crack distance, plastic zone and crack length is carried out. The results obtained are presented graphically.
Features of misoriented structures in a copper-copper bilayer plate obtained by explosive welding
Rybin, V. V.; Ushanova, E. A.; Zolotorevskii, N. Yu.
2013-09-01
Structures induced by deformation in the narrow zone of a contact between two copper plates that is prepared by explosive welding are systematically investigated at the micro-, meso-, and macrolevels. Plastic jets, regions of metal plastic flow anomalous localization, are discovered in areas adjacent to the contact surface. The defect structure of the plastic jets is examined by transmission electron microscopy and electron backscatter diffraction. It is shown that at the mesolevel the plastic jets are regions with a heavily fragmented structure. The statistics of the fragment distribution over misorientations and transverse sizes is studied.
Hwu, Chyanbin
2010-01-01
As structural elements, anisotropic elastic plates find wide applications in modern technology. The plates here are considered to be subjected to not only in plane load but also transverse load. In other words, both plane and plate bending problems as well as the stretching-bending coupling problems are all explained in this book. In addition to the introduction of the theory of anisotropic elasticity, several important subjects have are discussed in this book such as interfaces, cracks, holes, inclusions, contact problems, piezoelectric materials, thermoelastic problems and boundary element a
sprotocols
2014-01-01
1. Warm plates to room temperature before use. Cold plates causes the top agar to solidify irregularly. DO not warm plates to 37° as the top agar will take forever to solidify. - Prepare top agar as the appropriate liquid medium with 0.7% agar. Keeping 100 mL bottles is convenient. For phages, use λ top agar, which is less rich and yields bigger plaques. - Melt top agar in the microwave completely. Allow the agar to boil after liquification; incompletely melted agar looks liquid, but is...
Changes in Flat Plate Wake Characteristics Obtained With Decreasing Plate Thickness
Rai, Man Mohan
2016-01-01
The near and very near wake of a flat plate with a circular trailing edge is investigated with data from direct numerical simulations. Computations were performed for four different Reynolds numbers based on plate thickness (D) and at constant plate length. The value of ?/D varies by a factor of approximately 20 in the computations (? being the boundary layer momentum thickness at the trailing edge). The separating boundary layers are turbulent in all the cases. One objective of the study is to understand the changes in wake characteristics as the plate thickness is reduced (increasing ?/D). Vortex shedding is vigorous in the low ?/D cases with a substantial decrease in shedding intensity in the largest ?/D case (for all practical purposes shedding becomes almost intermittent). Other characteristics that are significantly altered with increasing ?/D are the roll-up of the detached shear layers and the magnitude of fluctuations in shedding period. These effects are explored in depth. The effects of changing ?/D on the distributions of the time-averaged, near-wake velocity statistics are discussed.
Best Practice Examples of Circular Business Models
DEFF Research Database (Denmark)
Guldmann, Eva
the textile and clothing sector as well as the durable goods sector. In order to appreciate the notion of circular business models, the basics of the circular economy are outlined along with three frameworks for categorizing the various types of circular business models. The frameworks take point of departure......, however, not the key focus of the current report. The point of the study is to describe the diverse and unique circular business models that companies around the globe have established already within the textile and clothing sector and within the durable goods sector. Even though these two sectors...... are tightly closed, whereas in other cases they are more open due to initiatives being voluntary, experimental or small scale, covering only part of the market. The study indicates that the ability of companies to apply life cycle thinking, which involves the entire value chain from sourcing to disposal...
Polarisation vision: beetles see circularly polarised light.
Warrant, Eric J
2010-07-27
It has long been known that the iridescent cuticle of many scarab beetles reflects circularly polarised light. It now turns out that scarabs can also see this light, potentially using it as a covert visual signal.
NMFS Scientific Publications Office: Legacy Series: Circulars
... Research related to the case for abstention, ... The Colorado River-Matagorda Bay study, by Charles H. Koski, p. 70-74; Movement of water masses ... Circular 191. Extent of acid mine pollution ...
Circular Phonon Dichroism in Weyl Semimetals
Liu, Donghao; Shi, Junren
2017-08-01
We derive the phonon dynamics of magnetic metals in the presence of strong spin-orbit coupling. We show that both a dissipationless viscosity and a dissipative viscosity arise in the dynamics. While the dissipationless viscosity splits the dispersion of left-handed and right-handed circularly polarized phonons, the dissipative viscosity damps them differently, inducing circular phonon dichroism. The effect offers a new degree of manipulation of phonons, i.e., the control of the phonon polarization. We investigate the effect in Weyl semimetals. We find that there exists strong circular phonon dichroism in Weyl semimetals breaking both the time-reversal and the inversion symmetry, making them potential materials for realizing the acoustic circular polarizer.
Possible Collapse Mode for Slender Reinforced Concrete Plates Subjected to Blast Load
Institute of Scientific and Technical Information of China (English)
ZHANG Xin; DU Xiuli; CHEN Zhen; ZENG Fanna
2008-01-01
This paper discusses the collapse mode of thin reinforced concrete (RC) plates subjected to blast load.To extend the well known plastic-mode method to analyze,not only perfectplastic plates,but also RC plates,it is needed to investigate the effect of material cracking on the collapse mode because the plate might have been cracked on both upper and lower surface before the plastic-mode fully develops,creating an unexpected type of collapse mode shape.A new failure mode is proposed and verified by numerical analysis in this paper.The new mode is a result of the material cracking and has an un-negligible effect on the reaction mechanism of the RC plate to the blast load.
Construction of Circular Economy Industrial System
Institute of Scientific and Technical Information of China (English)
Cao Man; Ye Wenhu
2007-01-01
It is difficult to realize the transformation from traditional economy industrial system to circular economy industrial system.Regarding primary raw materials as the indicators,the industrial system has been specified according to the divergence among the indicators and the circular utilization modes.In comparison with the association among industrial systems,the relationship among industrial sub-systems is named as industrial cross-linking in this paper.The industrial system which could completely utilize and recycle the indicators should be increased and strengthened,and the circular economy industrial system with complete industrial association and industrial cross-linking should also be constructed.Taking the development of circular agricultural system basing on the traditional agricultural system as an example,the traditional agricultural products are regarded as the indicators which have been divided into foodstuff and crop straws which are used to produce food and articlesfor use,like fertilizer,energy and papers etc.The way to construct the circular agricultural industrial system is to increase the industrial systems that could utilize the products generated from crop straws,feces and other castoffs and transform the wastewater and other trucks into environmental friendly products.It has also been pointed out that the construction of circular economy industrial system is conducive to the foundation of circular industrial economics and the establishment of the construction layout of circular economy and the application schemes.Suggestions to the theoretical and practical work of the next step have also been brought forward in this paper.
Unleashing the Power of the Circular Economy
Energy Technology Data Exchange (ETDEWEB)
Kok, L.; Wurpel, G.; Ten Wolde, A. [IMSA Amsterdam, Amsterdam (Netherlands)
2013-04-15
The concept of circular economy is an economic and industrial system that focuses on the reusability of products and raw materials, reduces value destruction in the overall system and aims at value creation within each tier of the system. This report for Circle Economy (CE) outlines the general direction and concrete steps that must be taken to accomplish a breakthrough to a circular economy. It also provides a knowledge base behind the concept, connecting it to sustainability.
A Conceptual Framework for Circular Design
Directory of Open Access Journals (Sweden)
Mariale Moreno
2016-09-01
Full Text Available Design has been recognised in the literature as a catalyst to move away from the traditional model of take-make-dispose to achieve a more restorative, regenerative and circular economy. As such, for a circular economy to thrive, products need to be designed for closed loops, as well as be adapted to generate revenues. This should not only be at the point of purchase, but also during use, and be supported by low-cost return chains and reprocessing structures, as well as effective policy and regulation. To date, most academic and grey literature on the circular economy has focused primarily on the development of new business models, with some of the latter studies addressing design strategies for a circular economy, specifically in the area of resource cycles and design for product life extension. However, these studies primarily consider a limited spectrum of the technical and biological cycles where materials are recovered and restored and nutrients (e.g., materials, energy, water are regenerated. This provides little guidance or clarity for designers wishing to design for new circular business models in practice. As such, this paper aims to address this gap by systematically analysing previous literature on Design for Sustainability (DfX (e.g., design for resource conservation, design for slowing resource loops and whole systems design and links these approaches to the current literature on circular business models. A conceptual framework is developed for circular economy design strategies. From this conceptual framework, recommendations are made to enable designers to fully consider the holistic implications for design within a circular economy.
Informative document waste plastics
Nagelhout D; Sein AA; Duvoort GL
1989-01-01
This "Informative document waste plastics" forms part of a series of "informative documents waste materials". These documents are conducted by RIVM on the indstruction of the Directorate General for the Environment, Waste Materials Directorate, in behalf of the program of
Hadley, Mary Jane
2010-01-01
Bobble heads had become quite popular, depicting all sorts of sports figures, animals, and even presidents. In this article, the author describes how her fourth graders made bobble head sculptures out of empty plastic drink bottles. (Contains 1 online resource.)
Cortical plasticity and rehabilitation.
Moucha, Raluca; Kilgard, Michael P
2006-01-01
The brain is constantly adapting to environmental and endogenous changes (including injury) that occur at every stage of life. The mechanisms that regulate neural plasticity have been refined over millions of years. Motivation and sensory experience directly shape the rewiring that makes learning and neurological recovery possible. Guiding neural reorganization in a manner that facilitates recovery of function is a primary goal of neurological rehabilitation. As the rules that govern neural plasticity become better understood, it will be possible to manipulate the sensory and motor experience of patients to induce specific forms of plasticity. This review summarizes our current knowledge regarding factors that regulate cortical plasticity, illustrates specific forms of reorganization induced by control of each factor, and suggests how to exploit these factors for clinical benefit.
Mechanical plasticity of cells
Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben
2016-10-01
Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.
Targeting tumour Cell Plasticity
Institute of Scientific and Technical Information of China (English)
Elizabeth D. WILLIAMS
2009-01-01
@@ Her research is focused on understanding the mechanisms of tumour progression and metastasis, particularly in uro-logical carcinomas (bladder and prostate). Tumour cell plasticity, including epithelial-mesenchymal transition, is a cen-tral theme in Dr Williams' work.
Full Text Available ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ... but changes the portion sizes so you are getting larger portions of non-starchy vegetables and a ...
Full Text Available ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ... 4/Box) Taking the guesswork out of portion control has never been easier. It can be a ...
Landalf, Helen
1998-01-01
Presents an activity that employs movement to enable students to understand concepts related to plate tectonics. Argues that movement brings topics to life in a concrete way and helps children retain knowledge. (DDR)
... our stage of life, situations, preferences, access to food, culture, traditions, and the personal decisions we make over time. All your food and beverage choices count. MyPlate offers ideas and ...
Full Text Available ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ... you have an easy portion control solution that works. Last Reviewed: October 8, 2015 Last Edited: September ...
Designing Assemblies Of Plates
Williams, F. W.; Kennedy, D.; Butler, R.; Aston, G.; Anderson, M. S.
1992-01-01
VICONOPT calculates vibrations and instabilities of assemblies of prismatic plates. Designed for efficient, accurate analysis of buckling and vibration, and for optimum design of panels of composite materials. Written in FORTRAN 77.
Full Text Available ... Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal Planning What Can I Eat? Making Healthy Food Choices Diabetes Superfoods Non-starchy Vegetables Grains and Starchy Vegetables ...
Full Text Available ... Recipes Association Cookbook Recipes Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning ... serving of dairy or both as your meal plan allows. Choose healthy fats in small amounts. For ...
Full Text Available ... 1 Diabetes Get Started Safely Get And Stay Fit Types of Activity Weight Loss Assess Your Lifestyle ... manage portion control wherever you are. Now, our best-selling, sectioned to-go plate with easy-sealing ...
Full Text Available ... Plate is a simple and effective way to manage your blood glucose levels and lose weight. With ... been easier. It can be a challenge to manage portion control wherever you are. Now, our best- ...
Landalf, Helen
1998-01-01
Presents an activity that employs movement to enable students to understand concepts related to plate tectonics. Argues that movement brings topics to life in a concrete way and helps children retain knowledge. (DDR)
Full Text Available ... Carbohydrates Carbohydrate Counting Make Your Carbs Count Glycemic ... to manage portion control wherever you are. Now, our best-selling, sectioned to-go plate with easy-sealing ...
Laser cutting plastic materials
Energy Technology Data Exchange (ETDEWEB)
Van Cleave, R.A.
1980-08-01
A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.
Localization of plastic deformation
Energy Technology Data Exchange (ETDEWEB)
Rice, J R
1976-04-01
The localization of plastic deformation into a shear band is discussed as an instability of plastic flow and a precursor to rupture. Experimental observations are reviewed, a general theoretical framework is presented, and specific calculations of critical conditions are carried out for a variety of material models. The interplay between features of inelastic constitutive description, especially deviations from normality and vertex-like yielding, and the onset of localization is emphasized.
Laminar circular hydraulic jumps without separation
Dasgupta, Ratul; Tomar, Gaurav; Govindarajan, Rama
2009-11-01
The traditional inviscid criterion for the occurrence of a planar, standing hydraulic jump is to have the Froude number decrease downstream and go through a value of 1 at some location. Here, upstream propagating, small-amplitude, long, non-dispersive gravity waves are trapped, and non-linear steepening is said to result in a near-discontinuous height profile, but it is not clear how. Such a condition on the Froude number is shown in the present axisymmetric Navier-Stokes computations to hold for a circular jump as well. The relevance of non-linear steepening to a circular jump is therefore a question we wish to answer. In circular jumps, moreover, a region of recirculation is usually observed underneath the jump, underlining the importance of viscosity in this process. This led Tani (J. Phys. Soc. Japan, 1949) to hypothesise that boundary-layer separation was the cause of the circular jump. This hypothesis has been debated extensively and the possibility of circular jumps without separation hinted at. In our simulations, we are able to obtain circular hydraulic jumps without any flow separation. This, and the necessity or otherwise of viscosity in jump formation will be discussed.
Fractal multifiber microchannel plates
Cook, Lee M.; Feller, W. B.; Kenter, Almus T.; Chappell, Jon H.
1992-01-01
The construction and performance of microchannel plates (MCPs) made using fractal tiling mehtods are reviewed. MCPs with 40 mm active areas having near-perfect channel ordering were produced. These plates demonstrated electrical performance characteristics equivalent to conventionally constructed MCPs. These apparently are the first MCPs which have a sufficiently high degree of order to permit single channel addressability. Potential applications for these devices and the prospects for further development are discussed.
Development of plastic surgery
Directory of Open Access Journals (Sweden)
Pećanac Marija Đ.
2015-01-01
Full Text Available Introduction. Plastic surgery is a medical specialty dealing with corrections of defects, improvements in appearance and restoration of lost function. Ancient Times. The first recorded account of reconstructive plastic surgery was found in ancient Indian Sanskrit texts, which described reconstructive surgeries of the nose and ears. In ancient Greece and Rome, many medicine men performed simple plastic cosmetic surgeries to repair damaged parts of the body caused by war mutilation, punishment or humiliation. In the Middle Ages, the development of all medical braches, including plastic surgery was hindered. New age. The interest in surgical reconstruction of mutilated body parts was renewed in the XVIII century by a great number of enthusiastic and charismatic surgeons, who mastered surgical disciplines and became true artists that created new forms. Modern Era. In the XX century, plastic surgery developed as a modern branch in medicine including many types of reconstructive surgery, hand, head and neck surgery, microsurgery and replantation, treatment of burns and their sequelae, and esthetic surgery. Contemporary and future plastic surgery will continue to evolve and improve with regenerative medicine and tissue engineering resulting in a lot of benefits to be gained by patients in reconstruction after body trauma, oncology amputation, and for congenital disfigurement and dysfunction.
PLANAR MOTION OF A SLIGHTLY DISTORTED CIRCULAR CYLINDER AROUND ANOTHER CIRCULAR ONE
Institute of Scientific and Technical Information of China (English)
SUN Ren; CHWANG Allen T.
2004-01-01
Accurate prediction of the motion of a body moving around another one in an unbounded fluid and determi-nation of the hydrodynamic interaction between them are im-portant in the coastal and offshore engineering. For two-dimensional cases, most of the previous studies were focused on the interaction between circular cylinders without considering the non-circular situation. To break through the limitation of"circular" bodies, in the present paper the boundary perturbation method was employed to investigate the motion of a slightly distorted circular cylinder around a circular one. An approximate complex velocity potential in terms of double infinite series expanded at two singular points was derived using the method of continued fractions. The hydrodynamic interaction between two cylinders was computed by solving the dynamical equations of motion. In a relative coordinate system moving with the uniform stream, the kinetic energy of the fluid was expressed as a function of fifteen added masses. Approximate analytical solutions of added masses in the series form were obtained and applied to determine the trajectories of the slightly distorted circular cylinder around a fixed circular one. Numerical results show that the presence of the circular cylinder affects the planar motion of the slightly distorted cirular cylinder and the initial configuration of the slightly distorted circular cylinder has a decisive influence on the development of its rotational motion.
Sorting Plastic Waste in Hydrocyclone
Directory of Open Access Journals (Sweden)
Ernestas Šutinys
2011-02-01
Full Text Available The article presents material about sorting plastic waste in hydrocyclone. The tests on sorting plastic waste were carried out. Also, the findings received from the performed experiment on the technology of sorting plastic waste are interpreted applying an experimental model of the equipment used for sorting plastics of different density.Article in Lithuanian
Vibration and Buckling of Web Plate of the Plate Girder
高橋, 和雄; 呉, 明強; 中澤, 聡志; 筑紫, 宏之
1998-01-01
The vibration and buckling of the web of the plate girder are studied in this paper. The small deflection theory of the thin plate is used. The finite strip method is employed to solve vibration and buckling of the plate girder. Natural frequenies of buckling properties are shown for various plate girder bridges.
Near-Field Acoustic Holography of Chladni Plate
Kim, Hyunhee; Kim, Yunbog; Jeon, Dongryul
2007-03-01
Characteristic modes of a Chladni plate can be visualized by sand gathering along the nodal lines. Although one can view two-dimensional vibration patterns, the sand pattern does not show a bending of antinode. We used near-field acoustic holography to reconstruct a three-dimensional image of circular and rectangular Chladni plates. The sound pressure was measured using four scanning microphones located 3 mm above a Chladni plate. A reference microphone was placed close to a speaker which drives the plate. A total of 60x60 data were collected from 30x30 cm^2 area and processed using MATLAB in accordance with the algorithm of near-field acoustic holography. The three-dimensional graphic image of the vibrating plate reconstructed this way not only matched the sand pattern but also visualized the bending of the plate. Propagation of the sound pressure could be also visualized three-dimensionally. The plot of sound pressure against the distance showed the 1/distance^2 dependence as expected. Sound is a difficult subject in physics class because it is invisible. Our results demonstrate that near-field acoustic holography combined with computer graphic is an effective tool to visualize the generation of a sound.
On the breakup of tectonic plates by polar wandering
Liu, H.-S.
1974-01-01
The equations for the stresses in a homogeneous shell of uniform thickness caused by a shift of the axis of rotation are derived. The magnitude of these stresses reaches a maximum value of the order of 10 to the 9th power dyn/sq cm, which is sufficient for explaining a tectonic breakup. In order to deduce the fracture pattern according to which the breakup of tectonic plates can be expected the theory of plastic deformation of shells is applied. The analysis of this pattern gives an explanation of the existing boundary systems of the major tectonic plates as described by Morgan (1968), LePichon (1968) and Isacks et al. (1968).
OPERATIONAL CIRCULAR NO 6 - JUNE 2001 'CERN SCIENTIFIC DOCUMENTS'
Human Resources Division
2001-01-01
This new operational circular has been drawn up. It cancels and replaces Administrative Circular N° 29 entitled "Principles and procedures governing CERN publications and reports and other publications arising from CERN work". Copies are available from Divisional Secretariats. Note : Administrative and operational circulars, as well as the lists of those in force, are available for consultation on WWW : ADMINISTRATIVE CIRCULARSOPERATIONAL CIRCULARS
Shape Control of Plates with Piezo Actuators and Collocated Position/Rate Sensors
Balakrishnan, A. V.
1994-01-01
This paper treats the control problem of shaping the surface deformation of a circular plate using embedded piezo-electric actuators and collocated rate sensors. An explicit Linear Quadratic Gaussian (LQG) optimizer stability augmentation compensator is derived as well as the optimal feed-forward control. Corresponding performance evaluation formulas are also derived.
Penetration of disk fragments following impact on thin plate
Institute of Scientific and Technical Information of China (English)
Juan-juan LI; Hai-jun XUAN; Lian-fang LIAO; Wei-rong HONG; Rong-ren WU
2009-01-01
To investigate the ballistic resistance and failure pattern of aeroengine casing following the impact of disk fragments,and to determine the optimum case structure,the phenomena of a 1/3rd disk fragment impact on single and double-layered thin plate targets were simulated using nonlinear dynamical analysis software MSC.Dytran.Strain rate effect was introduced in a Johnson-Cook (JC)material model for the disk fragment and the plate.Impact modeling was based on the Arbitrary Lagrange-Eulerian method,and simulated using explicit finite element method(FEM).Simulation results showed that the major failure pattern of the plate is shearing and tensile fracture with large plastic deformation.It Was also concluded that the ballistic limit velocity increases with the standoff distance when it iS beyond a certain value.and that greater resistance is obtained when the front plate has either a proportionately low or high thickness.The impact resistance of a double-layered plate may exceed that of a single plate if the thicknesses and standoff distance of the two plates are set appropriately.
Researches on Relationship between Circular Agriculture and Industrial Diversity
Institute of Scientific and Technical Information of China (English)
2011-01-01
First, this paper establishes the conceptual model of circular agriculture, conducts systematic analysis on the circular agriculture on the basis of conceptual model, and discusses the characteristics of closeness and openness of circular agriculture and relationship between closeness and openness of circular agriculture. Second, this paper introduces the industrial diversity related to circular agriculture, defines the concept of industry and the concept of industries related to agriculture, and illustrates the related industries that are conducive to circular agriculture and the related industries that are not conducive to circular agriculture. Finally, this paper analyzes the mutual relationship between circular agriculture and industrial diversity as follows: in the system of circular agriculture, the industrial diversity can transform the wastes in upstream industries into resources in downstream industries; the industrial diversity creates possibility for recycling of agricultural byproducts; the industrial diversity is conducive to the diversification of industries related to circular agriculture.
Bending and stretching of plates
Mansfield, E H; Hemp, W S
1964-01-01
The Bending and Stretching of Plates deals with elastic plate theory, particularly on small- and large-deflexion theory. Small-deflexion theory concerns derivation of basic equations, rectangular plates, plates of various shapes, plates whose boundaries are amenable to conformal transformation, plates with variable rigidity, and approximate methods. Large-deflexion theory includes general equations and some exact solutions, approximate methods in large-deflexion theory, asymptotic large-deflexion theories for very thin plates. Asymptotic theories covers membrane theory, tension field theory, a
Experimental Study of Damage Evolution in Circular Stirrup-Confined Concrete
Directory of Open Access Journals (Sweden)
Zuohua Li
2016-04-01
Full Text Available This paper presents an experimental study on circular stirrup-confined concrete specimens under uniaxial and monotonic load. The effects of stirrup volume ratio, stirrup yield strength and concrete strength on damage evolution of stirrup-confined concrete were investigated. The experimental results showed that the strength and ductility of concrete are improved by appropriate arrangement of the stirrup confinement. Firstly, the concrete damage evolution can be relatively restrained with the increase of the stirrup volume ratio. Secondly, higher stirrup yield strength usually causes larger confining pressures and slower concrete damage evolution. In contrast, higher concrete strength leads to higher brittleness, which accelerates the concrete damage evolution. A plastic strain expression is obtained through curve fitting, and a damage evolution equation for circular stirrup-confined concrete is proposed by introducing a confinement factor (C based on the experimental data. The comparison results demonstrate that the proposed damage evolution model can accurately describe the experimental results.
Institute of Scientific and Technical Information of China (English)
DING Fa-xing; YU Zhi-wu
2006-01-01
Based on reanalyzing test results of uniaxial compressive behavior of concrete at constant high temperatures in China,with the compressive cube strength of concrete from 20 to 80 Mpa, unified formulas for uniaxial compressive strength, elastic modulus, strain at peak uniaxial compression and mathematical expression for unaxial compressive stress-strain relations for the concrete at constant high temperatures were studied. Furthermore, the axial stress-axial strain relations between laterally confined concrete under axial compression and multiaxial stress-strain relations for steel at constant high temperatures were studied. Finally,based on continuum mechanics, the mechanics model for concentric cylinders of circular steel tube with concrete core of entire section loaded at constant high temperatures was established. Applying elasto-plastic analysis method, a FORTRAN program was developed, and the concrete-filled circular steel tubular (CFST) stub columns at constant high temperatures were analyzed. The analysis results are in agreement with the experiment ones from references.
Circular design - A manual on how to integrate circular design in buildings
Mac-lean, M.; Van Splunter, M.; Sun, X.
2014-01-01
This "designers' manual" is made during the TIDO-course AR0531 Innovation and Sustainability Circular design is based on two sustainability concepts: Cradle to Cradle® and circular economy. The former is more dogmatic and specific for the manufacturing and design industry, while the latter presents
Bright circularly polarized soft X-ray high harmonics for X-ray magnetic circular dichroism
Fan, Tingting; Grychtol, Patrik; Knut, Ronny; Hernández-García, Carlos; Hickstein, Daniel D.; Zusin, Dmitriy; Gentry, Christian; Dollar, Franklin J.; Mancuso, Christopher A.; Hogle, Craig W.; Kfir, Ofer; Legut, Dominik; Carva, Karel; Ellis, Jennifer L.; Dorney, Kevin M.; Chen, Cong; Shpyrko, Oleg G.; Fullerton, Eric E.; Cohen, Oren; Oppeneer, Peter M.; Milošević, Dejan B.; Becker, Andreas; Jaroń-Becker, Agnieszka A.; Popmintchev, Tenio; Murnane, Margaret M.; Kapteyn, Henry C.
2015-01-01
We demonstrate, to our knowledge, the first bright circularly polarized high-harmonic beams in the soft X-ray region of the electromagnetic spectrum, and use them to implement X-ray magnetic circular dichroism measurements in a tabletop-scale setup. Using counterrotating circularly polarized laser fields at 1.3 and 0.79 µm, we generate circularly polarized harmonics with photon energies exceeding 160 eV. The harmonic spectra emerge as a sequence of closely spaced pairs of left and right circularly polarized peaks, with energies determined by conservation of energy and spin angular momentum. We explain the single-atom and macroscopic physics by identifying the dominant electron quantum trajectories and optimal phase-matching conditions. The first advanced phase-matched propagation simulations for circularly polarized harmonics reveal the influence of the finite phase-matching temporal window on the spectrum, as well as the unique polarization-shaped attosecond pulse train. Finally, we use, to our knowledge, the first tabletop X-ray magnetic circular dichroism measurements at the N4,5 absorption edges of Gd to validate the high degree of circularity, brightness, and stability of this light source. These results demonstrate the feasibility of manipulating the polarization, spectrum, and temporal shape of high harmonics in the soft X-ray region by manipulating the driving laser waveform. PMID:26534992
Bright circularly polarized soft X-ray high harmonics for X-ray magnetic circular dichroism.
Fan, Tingting; Grychtol, Patrik; Knut, Ronny; Hernández-García, Carlos; Hickstein, Daniel D; Zusin, Dmitriy; Gentry, Christian; Dollar, Franklin J; Mancuso, Christopher A; Hogle, Craig W; Kfir, Ofer; Legut, Dominik; Carva, Karel; Ellis, Jennifer L; Dorney, Kevin M; Chen, Cong; Shpyrko, Oleg G; Fullerton, Eric E; Cohen, Oren; Oppeneer, Peter M; Milošević, Dejan B; Becker, Andreas; Jaroń-Becker, Agnieszka A; Popmintchev, Tenio; Murnane, Margaret M; Kapteyn, Henry C
2015-11-17
We demonstrate, to our knowledge, the first bright circularly polarized high-harmonic beams in the soft X-ray region of the electromagnetic spectrum, and use them to implement X-ray magnetic circular dichroism measurements in a tabletop-scale setup. Using counterrotating circularly polarized laser fields at 1.3 and 0.79 µm, we generate circularly polarized harmonics with photon energies exceeding 160 eV. The harmonic spectra emerge as a sequence of closely spaced pairs of left and right circularly polarized peaks, with energies determined by conservation of energy and spin angular momentum. We explain the single-atom and macroscopic physics by identifying the dominant electron quantum trajectories and optimal phase-matching conditions. The first advanced phase-matched propagation simulations for circularly polarized harmonics reveal the influence of the finite phase-matching temporal window on the spectrum, as well as the unique polarization-shaped attosecond pulse train. Finally, we use, to our knowledge, the first tabletop X-ray magnetic circular dichroism measurements at the N4,5 absorption edges of Gd to validate the high degree of circularity, brightness, and stability of this light source. These results demonstrate the feasibility of manipulating the polarization, spectrum, and temporal shape of high harmonics in the soft X-ray region by manipulating the driving laser waveform.
A broadband, circular-polarization selective surface
Momeni Hasan Abadi, Seyed Mohamad Amin; Behdad, Nader
2016-06-01
We introduce a new technique for designing wideband circular-polarization selective surfaces (CPSSs) based on anisotropic miniaturized element frequency selective surfaces. The proposed structure is a combination of two linear-to-circular polarization converters sandwiching a linear polarizer. This CPSS consists of a number of metallic layers separated from each other by thin dielectric substrates. The metallic layers are in the form of two-dimensional arrays of subwavelength capacitive patches and inductive wire grids with asymmetric dimensions and a wire grid polarizer with sub-wavelength period. The proposed device is designed to offer a wideband circular-polarization selection capability allowing waves with left-hand circular polarization to pass through while rejecting those having right-hand circular polarization. A synthesis procedure is developed that can be used to design the proposed CPSS based on its desired band of operation. Using this procedure, a prototype of the proposed CPSS operating in the 12-18 GHz is designed. Full-wave electromagnetic simulations are used to predict the response of this structure. These simulation results confirm the validity of the proposed design concept and synthesis procedure and show that proposed CPSS operates within a fractional bandwidth of 40% with a co-polarization transmission discrimination of more than 15 dB. Furthermore, the proposed design is shown to be capable of providing an extremely wide field of view of ±60°.
A COMPACT CIRCULARLY POLARIZED SLOTTED MICROSTRIP ANTENNA
Directory of Open Access Journals (Sweden)
V. Jebaraj
2014-12-01
Full Text Available Slot antennas are often used at UHF and microwave frequencies. In slot antenna for RFID reader applications the frequency ranges from 902-923MHz to achieve circular polarization. The shapes and size of the slot, as well as the driving frequency, determine the radiation distribution pattern. The proposed compact size circularly polarized slotted microstrip antenna are summarized with design rules. The circularly polarized radiation in square patch antenna can be obtained by perturbation technique with different shapes of slot in the orthogonal direction. A single feed configuration based symmetric slotted microstrip antenna is adapted to realize the compact circularly polarized microstrip antennas. Based on the perimeter, the size of the slot on microstrip slot antenna are studied and compared. The Operating frequency of the antenna is 912MHz that can be tuned by varying the perimeter of the slot while the keeping the circularly polarized radiation unchanged. The schematic and layout are configured by using Advanced Design System (ADS. Return loss, Resonant Frequency, Axial Ratio (AR, and Gain were determined for the proposed system using ADS. A measured 3dB Axial Ratio (AR bandwidth around 6MHz with 16MHz impedance bandwidth has been achieved for the antenna on a RO3004C substrate with dielectric constant 3.38.
Circular and Elliptic Submerged Impinging Water Jets
Claudey, Eric; Benedicto, Olivier; Ravier, Emmanuel; Gutmark, Ephraim
1999-11-01
Experiments and CFD have been performed to study circular and elliptic jets in a submerged water jet facility. The tests included discharge coefficient measurement to evaluate pressure losses encountered in noncircular nozzles compared to circular ones. Three-dimensional pressure mappings on the impingement surface and PIV measurement of the jet mean and turbulent velocity have been performed at different compound impingement angles relative to the impingement surface and at different stand-off distances. The objective was to investigate the effect of the non-circular geometry on the flow field and on the impact region. The tests were performed in a close loop system in which the water was pumped through the nozzles into a clear Plexiglas tank. The Reynolds numbers were typically in the range of 250000. Discharge coefficients of the elliptic nozzle was somewhat lower than that of the circular jet but spreading rate and turbulence level were higher. Pressure mapping showed that the nozzle exit geometry had an effect on the pressure distribution in the impact region and that high-pressure zones were generated at specific impact points. PIV measurements showed that for a same total exit area, the elliptic jets affected a surface area that is 8the equivalent circular. The turbulence level in the elliptic jet tripled due to the nozzle design. Results of the CFD model were in good agreement with the experimental data.
Environmental issues elimination through circular economy
Špirková, M.; Pokorná, E.; Šujanová, J.; Samáková, J.
2016-04-01
Environmental efforts of European Union are currently going towards circular economy. Tools like Extended Producer Responsibility and Eco-design were established. The circular economy deals with resources availability issue on one hand and waste management on the other hand. There are few pioneering companies all over the world with some kind of circular economy practice. Generally the concept is not very wide-spread. The paper aims to evaluate possibility of transition towards circular economy in Slovak industrial companies. They need to have an active approach to material treatment of their products after usage stage. Innovation is another important pre-condition for the transition. Main problem of current cradle to grave system is landfilling of valuable materials after one cycle of usage. Their potential value for next manufacturing cycles is lost. Companies may do not see connection between waste management and material resource prices and volatility of supplies. Municipalities are responsible for municipal waste collection and treatment in Slovakia. The circular economy operates by cradle to cradle principle. Company manages material flow until the material comes back to the beginning of manufacturing process by itself or by another partners. Stable material supplies with quite low costs are provided this way. It is necessary to deal with environmental problems in phase of product design. Questionnaire survey results show on one hand low involvement of industrial companies in waste management area, however on the other hand they are open to environmental innovations in future.
Environmental issues elimination through circular economy
Energy Technology Data Exchange (ETDEWEB)
Špirková, M., E-mail: marta.spirkova@stuba.sk; Pokorná, E.; Šujanová, J.; Samáková, J. [Paulínska 16, 917 24 Trnava, Slovakia, Slovak University of Technology in Bratislava, Faculty of Materials Science and Technology in Trnava (Slovakia)
2016-04-21
Environmental efforts of European Union are currently going towards circular economy. Tools like Extended Producer Responsibility and Eco-design were established. The circular economy deals with resources availability issue on one hand and waste management on the other hand. There are few pioneering companies all over the world with some kind of circular economy practice. Generally the concept is not very wide-spread. The paper aims to evaluate possibility of transition towards circular economy in Slovak industrial companies. They need to have an active approach to material treatment of their products after usage stage. Innovation is another important pre-condition for the transition. Main problem of current cradle to grave system is landfilling of valuable materials after one cycle of usage. Their potential value for next manufacturing cycles is lost. Companies may do not see connection between waste management and material resource prices and volatility of supplies. Municipalities are responsible for municipal waste collection and treatment in Slovakia. The circular economy operates by cradle to cradle principle. Company manages material flow until the material comes back to the beginning of manufacturing process by itself or by another partners. Stable material supplies with quite low costs are provided this way. It is necessary to deal with environmental problems in phase of product design. Questionnaire survey results show on one hand low involvement of industrial companies in waste management area, however on the other hand they are open to environmental innovations in future.
DUAL RECIPROCITY BOUNDARY ELEMENT METHOD FOR FLEXURAL WAVES IN THIN PLATE WITH CUTOUT
Institute of Scientific and Technical Information of China (English)
GAO Suo-wen; WANG Yue-sheng; ZHANG Zi-mao; MA Xing-rui
2005-01-01
The theoretical analysis and numerical calculation of scattering of elastic waves and dynamic stress concentrations in the thin plate with the cutout was studied using dual reciprocity boundary element method (DRM). Based on the work equivalent law, the dual reciprocity boundary integral equations for flexural waves in the thin plate were established using static fundamental solution. As illustration, numerical results for the dynamic stress concentration factors in the thin plate with a circular hole are given.The results obtained demonstrate good agreement with other reported results and show high accuracy.
Analysis of Shrinkage on Thick Plate Part using Genetic Algorithm
Directory of Open Access Journals (Sweden)
Najihah S.N.
2016-01-01
Full Text Available Injection moulding is the most widely used processes in manufacturing plastic products. Since the quality of injection improves plastic parts are mostly influenced by process conditions, the method to determine the optimum process conditions becomes the key to improving the part quality. This paper presents a systematic methodology to analyse the shrinkage of the thick plate part during the injection moulding process. Genetic Algorithm (GA method was proposed to optimise the process parameters that would result in optimal solutions of optimisation goals. Using the GA, the shrinkage of the thick plate part was improved by 39.1% in parallel direction and 17.21% in the normal direction of melt flow.
Korman, M. S.; Duong, D. V.; Kalsbeck, A. E.
2015-10-01
An apparatus (SPO), designed to study flexural vibrations of a soil loaded plate, consists of a thin circular elastic clamped plate (and cylindrical wall) supporting a vertical soil column. A small magnet attached to the center of the plate is driven by a rigid AC coil (located coaxially below the plate) to complete the electrodynamic soil plate oscillator SPO design. The frequency dependent mechanical impedance Zmech (force / particle velocity, at the plate's center) is inversely proportional to the electrical motional impedance Zmot. Measurements of Zmot are made using the complex output to input response of a Wheatstone bridge that has an identical coil element in one of its legs. Near resonance, measurements of Zmot (with no soil) before and after a slight point mass loading at the center help determine effective mass, spring, damping and coupling constant parameters of the system. "Tuning curve" behavior of real{ Zmot } and imaginary{ Zmot } at successively higher vibration amplitudes of dry sifted masonry sand are measured. They exhibit a decrease "softening" in resonance frequency along with a decrease in the quality Q factor. In soil surface vibration measurements a bilinear hysteresis model predicts the tuning curve shape for this nonlinear mesoscopic elastic SPO behavior - which also models the soil vibration over an actual plastic "inert" VS 1.6 buried landmine. Experiments are performed where a buried 1m cube concrete block supports a 12 inch deep by 30 inch by 30 inch concrete soil box for burying a VS 1.6 in dry sifted masonry sand for on-the-mine and off-the-mine soil vibration experiments. The backbone curve (a plot of the peak amplitude vs. corresponding resonant frequency from a family of tuning curves) exhibits mostly linear behavior for "on target" soil surface vibration measurements of the buried VS 1.6 or drum-like mine simulants for relatively low particle velocities of the soil. Backbone curves for "on target" measurements exhibit
Directory of Open Access Journals (Sweden)
Gonugunta V
2005-01-01
Full Text Available Although anterior cervical instrumentation was initially used in cervical trauma, because of obvious benefits, indications for its use have been expanded over time to degenerative cases as well as tumor and infection of the cervical spine. Along with a threefold increase in incidence of cervical fusion surgery, implant designs have evolved over the last three decades. Observation of graft subsidence and phenomenon of stress shielding led to the development of the new generation dynamic anterior cervical plating systems. Anterior cervical plating does not conclusively improve clinical outcome of the patients, but certainly enhances the efficacy of autograft and allograft fusion and lessens the rate of pseudoarthrosis and kyphosis after multilevel discectomy and fusions. A review of biomechanics, surgical technique, indications, complications and results of various anterior cervical plating systems is presented here to enable clinicians to select the appropriate construct design.
Nondestructive Quantification of Local Plasticizer Concentration in PVC by (1)H NMR Relaxometry.
Adams, Alina; Kwamen, Rance; Woldt, Benjamin; Graß, Michael
2015-12-01
The properties of plasticized poly(vinyl chloride) (PVC) , one of the most important polymers today, are strongly dictated by the concentration of plasticizer. Yet, it has been impossible to quantify this concentration at different positions inside a PVC product without its destruction because of a lack of suitable analytical methods. Thus, this paper introduces a simple, fast, and efficient way to determine truly nondestructively the concentration of plasticizer in PVC by single-sided nuclear magnetic resonance (NMR). With the help of correlation curves between the concentration of plasticizer inside nonaged PVC samples and the corresponding volume-averaged NMR parameters, single-sided NMR allows the quantification of the local concentration of plasticizer in aged PVC plates at different depths by spatially resolved relaxation measurements. The presented approach represents a fundamental step toward in situ characterization of plasticized PVC.
An Investigation on Thermal Recycling of Recycled Plastic Resin
Yamakita, Ryuji; Miura, Katsuya; Ishino, Yojiro; Ohiwa, Norio
Thermal recycling of recycled plastic resin is focused in this investigation. Fine grinding of plastic resin and preparation of high temperature oxidizing atmosphere are indispensable for effective and successful burn-up of plastic resin. Polyethylene terephthalate resin powder is employed and high temperature oxidizing atmosphere is generated downstream an annular burner. Through a circular nozzle set coaxially in the closed bottom end of the annular burner, PET-powder and propane-air mixture are issued vertically upward into the high temperature oxidizing atmosphere. Temperature and O2 concentration fields downstream the annular burner are first examined by varying the circular jet equivalence ratio with the air flow rate kept constant and without PET-powder supply. PET-powder having a mass-median diameter of either 89.7µm or 145µm is then issued into the high temperature region along with propane-air mixture by varying the PET-powder mass flow rate. Appearances of the PET-powder flame are observed using a high-speed CCD video camera and unburnt PET particles are traced during their passages in the high temperature region. Variation of O2 concentration fields due to PET-powder combustion is also measured in the PET flame. According to the results, overall limit conditions for effective burn-up of PET-powder are finally discussed.
License plate detection algorithm
Broitman, Michael; Klopovsky, Yuri; Silinskis, Normunds
2013-12-01
A novel algorithm for vehicle license plates localization is proposed. The algorithm is based on pixel intensity transition gradient analysis. Near to 2500 natural-scene gray-level vehicle images of different backgrounds and ambient illumination was tested. The best set of algorithm's parameters produces detection rate up to 0.94. Taking into account abnormal camera location during our tests and therefore geometrical distortion and troubles from trees this result could be considered as passable. Correlation between source data, such as license Plate dimensions and texture, cameras location and others, and parameters of algorithm were also defined.
Charged Particle Optics in Circular Higgs Factory
Energy Technology Data Exchange (ETDEWEB)
Cai, Yunhai [SLAC National Accelerator Lab., Menlo Park, CA (United States)
2015-02-26
Similar to a super B-factory, a circular Higgs factory will require strong focusing systems near the interaction points and a low-emittance lattice in arcs to achieve a factory luminosity. At electron beam energy of 120 GeV, beamstrahlung effects during the collision pose an additional challenge to the collider design. In particular, a large momentum acceptance at 2 percent level is necessary to retain an adequate beam lifetime. This turns out to be the most challenging aspect in the design of circular Higgs factory. In this paper, an example will be provided to illustrate the beam dynamics in circular Higgs factory, emphasizing on the chromatic optics. Basic optical modules and advanced analysis will be presented. Most important, we will show that 2% momentum aperture is achievable
Circular object recognition based on shape parameters
Institute of Scientific and Technical Information of China (English)
Chen Aijun; Li Jinzong; Zhu Bing
2007-01-01
To recognize circular objects rapidly in satellite remote sensing imagery, an approach using their geometry properties is presented.The original image is segmented to be a binary one by one dimension maximum entropy threshold algorithm and the binary image is labeled with an algorithm based on recursion technique.Then, shape parameters of all labeled regions are calculated and those regions with shape parameters satisfying certain conditions are recognized as circular objects.The algorithm is described in detail, and comparison experiments with the randomized Hough transformation (RHT) are also provided.The experimental results on synthetic images and real images show that the proposed method has the merits of fast recognition rate, high recognition efficiency and the ability of anti-noise and anti-jamming.In addition, the method performs well when some circular objects are little deformed and partly misshapen.
Response-Adaptive Allocation for Circular Data.
Biswas, Atanu; Dutta, Somak; Laha, Arnab Kumar; Bakshi, Partho K
2015-01-01
Response-adaptive designs are used in phase III clinical trials to allocate a larger proportion of patients to the better treatment. Circular data is a natural outcome in many clinical trial setup, e.g., some measurements in opthalmologic studies, degrees of rotation of hand or waist, etc. There is no available work on response-adaptive designs for circular data. With reference to a dataset on cataract surgery we provide some response-adaptive designs where the responses are of circular nature and propose some test statistics for treatment comparison under adaptive data allocation procedure. Detailed simulation study and the analysis of the dataset, including redesigning the cataract surgery data, are carried out.
Circular bacteriocins: biosynthesis and mode of action.
Gabrielsen, Christina; Brede, Dag A; Nes, Ingolf F; Diep, Dzung B
2014-11-01
Circular bacteriocins are a group of N-to-C-terminally linked antimicrobial peptides, produced by Gram-positive bacteria of the phylum Firmicutes. Circular bacteriocins generally exhibit broad-spectrum antimicrobial activity, including against common food-borne pathogens, such as Clostridium and Listeria spp. These peptides are further known for their high pH and thermal stability, as well as for resistance to many proteolytic enzymes, properties which make this group of bacteriocins highly promising for potential industrial applications and their biosynthesis of particular interest as a possible model system for the synthesis of highly stable bioactive peptides. In this review, we summarize the current knowledge on this group of bacteriocins, with emphasis on the recent progress in understanding circular bacteriocin genetics, biosynthesis, and mode of action; in addition, we highlight the current challenges and future perspectives for the application of these peptides.
Structure and genetics of circular bacteriocins.
van Belkum, Marco J; Martin-Visscher, Leah A; Vederas, John C
2011-08-01
Circular bacteriocins are antimicrobial peptides produced by a variety of Gram-positive bacteria. They are part of a growing family of ribosomally synthesized peptides with a head-to-tail cyclization of their backbone that are found in mammals, plants, fungi and bacteria and are exceptionally stable. These bacteriocins permeabilize the membrane of sensitive bacteria, causing loss of ions and dissipation of the membrane potential. Most circular bacteriocins probably adopt a common 3D structure consisting of four or five α-helices encompassing a hydrophobic core. This review compares the various structures, as well as the gene clusters that encode circular bacteriocins, and discusses the biogenesis of this unique class of bacteriocins.
Equatorial circular motion in Kerr spacetime
Pugliese, Daniela; Ruffini, Remo
2011-01-01
We analyze the properties of circular orbits of test particles on the equatorial plane of a rotating central mass whose gravitational field is described by the Kerr spacetime. For rotating black holes and naked singularities we explore all the spatial regions where circular orbits can exist and analyze the behavior of the energy and the angular momentum of the corresponding test particles. In particular, we find all the radii at which a test particle can have zero angular momentum due to the repulsive gravity effects generated by naked singularities. We classify all the stability zones of circular orbits. It is shown that the geometric structure of the stability zones of black holes is completely different from that of naked singularities.
Wood Crosscutting Process Analysis for Circular Saws
Directory of Open Access Journals (Sweden)
Jozef Krilek
2016-11-01
Full Text Available This article deals with the influence of some cutting parameters (geometry of cutting edge, wood species, and circular saw type and cutting conditions on the wood crosscutting process carried out with circular saws. The establishment of torque values and feeding power for the crosswise wood cutting process has significant implications for designers of crosscutting lines. The conditions of the experiments are similar to the working conditions of real machines, and the results of individual experiments can be compared with the results obtained via similar experimental workstations. Knowledge of the wood crosscutting process, as well as the choice of suitable cutting conditions and tools could decrease wood production costs and save energy. Changing circular saw type was found to have the biggest influence on cutting power of all factors tested.
Circularly symmetric light scattering from nanoplasmonic spirals.
Trevino, Jacob; Cao, Hui; Dal Negro, Luca
2011-05-11
In this paper, we combine experimental dark-field imaging, scattering, and fluorescence spectroscopy with rigorous electrodynamics calculations in order to investigate light scattering from planar arrays of Au nanoparticles arranged in aperiodic spirals with diffuse, circularly symmetric Fourier space. In particular, by studying the three main types of Vogel's spirals fabricated by electron-beam lithography on quartz substrates, we demonstrate polarization-insensitive planar light diffraction in the visible spectral range. Moreover, by combining dark-field imaging with analytical multiparticle calculations in the framework of the generalized Mie theory, we show that plasmonic spirals support distinctive structural resonances with circular symmetry carrying orbital angular momentum. The engineering of light scattering phenomena in deterministic structures with circular Fourier space provides a novel strategy for the realization of optical devices that fully leverage on enhanced, polarization-insensitive light-matter coupling over planar surfaces, such as thin-film plasmonic solar cells, plasmonic polarization devices, and optical biosensors.
Progress in Circular SAR Imaging Technique
Directory of Open Access Journals (Sweden)
Hong Wen
2012-06-01
Full Text Available Circular SAR (CSAR is a newly developed all-directional high resolution 3D imaging mode in recent years, to satisfy the demand of finer observation. The National Key Laboratory of Science and Technology on Microwave Imaging, Institute of Electronics, Chinese Academy of Sciences (MITL, IECAS, had the first test flight experiment in Aug. 2011 with a P-band full polarization SAR system, and successfully obtained the all-directional high resolution circular SAR image. The initial results show that CSAR technique has the encouraging potential capability in the fields of high precision mapping, disaster evaluation, resource management and the other related applications. This paper firstly makes a detailed discussion on the progress of circular SAR imaging technique, which emphases on the several airborne experiments performed these years to show CSAR’s attractive features, then studies and illustrates the key techniques, and finally discusses the development trends.
Circular symmetry in the Hitchin system
Kamata, Masaru
2013-01-01
To study circularly symmetric field configurations in the SU(2) Hitchin system an SO(2) symmetry, [J_3, \\phi]=0 and [J_3, A_{\\pm}]=\\pm A_{\\pm}, is imposed on the Higgs scalar \\phi and the gauge fields A_{\\pm} of the system, respectively, where J_3 is a sum of the third components of the orbital angular momenta and the generators of the SU(2). The circular symmetry and the equation \\bar{D}\\phi=0 yield onstant, generally nonzero, vacuum expectation values for {\\rm Tr}(\\phi^{2}). The equation 4F_{z\\bar{z}}=[\\phi, \\phi^{*}] yields a system of differential equations which govern the circularly symmetric field configurations and an exact solution to these equations in a pure gauge form with nontrivial Higgs scalar is obtained.
Experimental evidence for circular inference in schizophrenia
Jardri, Renaud; Duverne, Sandrine; Litvinova, Alexandra S.; Denève, Sophie
2017-01-01
Schizophrenia (SCZ) is a complex mental disorder that may result in some combination of hallucinations, delusions and disorganized thinking. Here SCZ patients and healthy controls (CTLs) report their level of confidence on a forced-choice task that manipulated the strength of sensory evidence and prior information. Neither group's responses can be explained by simple Bayesian inference. Rather, individual responses are best captured by a model with different degrees of circular inference. Circular inference refers to a corruption of sensory data by prior information and vice versa, leading us to `see what we expect' (through descending loops), to `expect what we see' (through ascending loops) or both. Ascending loops are stronger for SCZ than CTLs and correlate with the severity of positive symptoms. Descending loops correlate with the severity of negative symptoms. Both loops correlate with disorganized symptoms. The findings suggest that circular inference might mediate the clinical manifestations of SCZ.
METHOD OF CONJUGATED CIRCULAR ARCS TRACING
Directory of Open Access Journals (Sweden)
N. Ageyev Vladimir
2017-01-01
Full Text Available The geometric properties of conjugated circular arcs connecting two points on the plane with set directions of tan- gent vectors are studied in the work. It is shown that pairs of conjugated circular arcs with the same conditions in frontier points create one-parameter set of smooth curves tightly filling all the plane. One of the basic properties of this set is the fact that all coupling points of circular arcs are on the circular curve going through the initially given points. The circle radius depends on the direction of tangent vectors. Any point of the circle curve, named auxiliary in this work, determines a pair of conjugated arcs with given boundary conditions. One more condition of the auxiliary circle curve is that it divides the plane into two parts. The arcs going from the initial point are out of the circle limited by this circle curve and the arcs coming to the final point are inside it. These properties are the basis for the method of conjugated circular arcs tracing pro- posed in this article. The algorithm is rather simple and allows to fulfill all the needed plottings using only the divider and ruler. Two concrete examples are considered. The first one is related to the problem of tracing of a pair of conjugated arcs with the minimal curve jump when going through the coupling point. The second one demonstrates the possibility of trac- ing of the smooth curve going through any three points on the plane under condition that in the initial and final points the directions of tangent vectors are given. The proposed methods of conjugated circular arcs tracing can be applied in solving of a wide variety of problems connected with the tracing of cam contours, for example pattern curves in textile industry or in computer-aided-design systems when programming of looms with numeric control.
A computational study of particle deposition patterns from a circular laminar jet
Feng, James Q
2016-01-01
Particle deposition patterns on the plate of inertial impactor with circular laminar jet are investigated numerically with a Lagrangian solver implemented within the framework of the OpenFOAM$^{\\circledR}$ CFD package. Effects of taper angle of the nozzle channel and jet-to-plate distance are evaluated. The results show that tapered nozzle tends to deposit more particles toward the circular spot edge than straight nozzle. At jet Reynolds number $Re = 1132$, a tapered nozzle deposits particles to form a pattern with a high density ring toward the deposition spot edge, especially for particle Stokes number $St > St_{50}$, which is absent with a straight nozzle. Increasing the jet-to-plate distance tends to reduce the value of particle density peak near deposition spot edge. Reducing $Re$ to $283$ (e.g., for $300$ ccm flow through a $1.5$ mm diameter jet nozzle) yields particle deposition patterns without the high density ring at the deposition spot edge when the same tapered nozzle is used. The particle deposit...
Material recycling: Presence of chemicals and their influence on the circular economy concept
DEFF Research Database (Denmark)
Pivnenko, Kostyantyn; Astrup, Thomas Fruergaard
2014-01-01
Linear production concept (extract-convert-use-discard) applied from the times of industrial revolution hascreated a lot of skepticism in the world of limited resources that we live in. As basis to tackle the issue of resource scarcity, circular economy concept has been proposed. The backbone...... of the concept is the pursuit of sustainability through re-use and recycling of products and materials once they have served their purpose. Once such materials (e.g. paper, plastics) are recycled, chemicals that they contain are reintroduced,spread or even accumulate in the newly manufactured products (Figure 1...
Casimir force between metal plate and dielectric plate
Institute of Scientific and Technical Information of China (English)
刘中柱; 邵成刚; 罗俊
1999-01-01
The Casimir effect between metal plate and dielectric plate is discussed with 1+1-dimensional potential model without using cut-off method. Calculation shows that the Casimir force between metal plate and dielectric plate is determined not only by the potential V0, the dielectric thickness and the distance α between the metal plate and dielectric plate, but also by the dimension of the vessel. When α is far less than the dimension of the vessel, the Casimir force Fc∝α（-1）; conversely Fc∝α-2. This result is significant for Casimir force experiment.
Tailoring Very-High-n Circular Wavepackets
Energy Technology Data Exchange (ETDEWEB)
Reinhold, Carlos O [ORNL; Yoshida, S. [Vienna University of Technology, Austria; Burgdorfer, J. [Vienna University of Technology, Austria; Mestayer, J. J. [Rice University; Wyker, B. [Rice University; Lancaster, J. C. [Rice University; Dunning, F. B. [Rice University
2008-01-01
We describe a protocol to generate transiently localized circular wavepackets in very-high-n Rydberg states. These are created from strongly-polarized quasi-one-dimensional Rydberg states by applying a transverse pulsed electric field. The resulting wavepacket becomes transiently localized as the result of focusing and travels in a nearly circular Bohr-like orbit around the nucleus for several orbital periods. The localization properties can be controlled by carefully choosing the shape of the field pulse, in particular, its rise and fall times. Remarkably, the wavepackets exhibit classical revivals after the initial dephasing on time scales shorter than those expected for quantum revivals.
Best Practice Examples of Circular Business Models
DEFF Research Database (Denmark)
Guldmann, Eva
are tightly closed, whereas in other cases they are more open due to initiatives being voluntary, experimental or small scale, covering only part of the market. The study indicates that the ability of companies to apply life cycle thinking, which involves the entire value chain from sourcing to disposal...... are different, circular business models can be found in both. These models operate in both young and mature firms, small and large, which points to the fact that circular business models can be successfully implemented in a wide range of business settings as long as they are individually tailored to each...
Rectangular-to-circular groove waveguide junction
Institute of Scientific and Technical Information of China (English)
CUI; Licheng; (崔立成); YANG; Hongsheng; (杨鸿生)
2003-01-01
Mode matching method is used to analyze the scattering characteristics of the rectangular-to-circular groove waveguide junction. Firstly, the scattering matrix equation is obtained by matching the electromagnetic fields at the boundary of the junction. The scattering coefficients can be obtained from the equation. Secondly the scattering characteristics of the iris with rectangular window positioned in circular groove waveguide are briefly analyzed. Thirdly, the convergent problem is discussed and the numerical results are given. At last experiment is made and good agreement is found between the calculated results and the measured results.
Free vibrations of circular cylindrical shells
Armenàkas, Anthony E; Herrmann, George
1969-01-01
Free Vibrations of Circular Cylindrical Shells deals with thin-walled structures that undergo dynamic loads application, thereby resulting in some vibrations. Part I discusses the treatment of problems associated with the propagation of plane harmonic waves in a hollow circular cylinder. In such search for solutions, the text employs the framework of the three-dimensional theory of elasticity. The text explains the use of tables of natural frequencies and graphs of representative mode shapes of harmonic elastic waves bounding in an infinitely long isotropic hollow cylinder. The tables are
Circular economy in China and recommendations
Institute of Scientific and Technical Information of China (English)
Zhou Hongchun
2006-01-01
@@ It is an overall, urgent and long-term strategic task for China to vigorously develop the circular economy and build a resource-saving and environmental-friendly society. China is now at the accelerating stage of industrialization and urbanization.Lower per-capita resource amount and tendency of environmental deterioration has not been fundamentally averted. Therefore a circular economy development is an inevitable choice to realize the goal of building a well-off society, ensure sustainable development of national economy, and coordinate the relationship between mankind and nature.
Institute of Scientific and Technical Information of China (English)
ZHOU Xiao-ping; LING Tong-hua
2005-01-01
The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The solutions include: the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near crack line, law that the length of the plastic zone along the crack line is varied with an external loads, and the bearing capacity of an infinite plate with a center crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of the small scale yielding theory have not been made and no other assumption have been taken.
Institute of Scientific and Technical Information of China (English)
王成; 吴承平
2003-01-01
The improved near crack line analysis method was used to investigate aneccentric cracked plate loaded by two pairs of anti-plane point forces at the crack surface inan elastic-perfectly plastic solid. The analytical solutions of the elastic-plastic stress fieldsand displacements near the crack line have been found without the assumptions of the smallscale yielding. The law that the length of the plastic zone along the crack line is varied withan external loads and the bearing capacity of an eccentric cracked plate are obtained.
Nuclear reactor alignment plate configuration
Energy Technology Data Exchange (ETDEWEB)
Altman, David A; Forsyth, David R; Smith, Richard E; Singleton, Norman R
2014-01-28
An alignment plate that is attached to a core barrel of a pressurized water reactor and fits within slots within a top plate of a lower core shroud and upper core plate to maintain lateral alignment of the reactor internals. The alignment plate is connected to the core barrel through two vertically-spaced dowel pins that extend from the outside surface of the core barrel through a reinforcement pad and into corresponding holes in the alignment plate. Additionally, threaded fasteners are inserted around the perimeter of the reinforcement pad and into the alignment plate to further secure the alignment plate to the core barrel. A fillet weld also is deposited around the perimeter of the reinforcement pad. To accomodate thermal growth between the alignment plate and the core barrel, a gap is left above, below and at both sides of one of the dowel pins in the alignment plate holes through with the dowel pins pass.
Stability of Propofol in Polystyrene-Based Tissue Culture Plates
Sall, Jeffrey W.; Leong, Jason
2013-01-01
Propofol has been reported to have high stability in glass and relatively high stability up to 24 hours in polyvinyl chloride-based medical plastics. Recent publications have observed the effects of propofol on cells and tissues grown in culture. Many cell culture plastics are formulated from polystyrene but we could find little information on the stability of propofol exposed to these products. We observed very little change in the concentration of propofol diluted in cell culture medium over 24 hours when exposed to glass, but substantial loss of the drug when exposed to 96-well polystyrene cell culture plates. This decrease was most rapid in the first hour but continued until 24 hours. The type of plastic used in cell and tissue culture experiments with propofol may influence the results by increasing the apparent dose required to see an effect. PMID:23632056
SABIC Innovative Plastics: Be the World Best Plastic Resin Manufacturer
Institute of Scientific and Technical Information of China (English)
Jenny Du
2007-01-01
@@ "SABIC Innovative Plastics is a global supplier of plastic resins, manufacturing and compounding polycarbonate, ABS, SAN, ASA, PPE, PC/ABS, PBT and PEI resins, as well as the LNP* line of high performance specialty compounds," said Hiroshi Yoshida, the Global Market Director for Electronics of SABIC Innovative Plastics based in Tokyo at the press conference held by SABIC Innovative Plastics, November 8th 2007, Shanghai.
Forming Of Spherical Titanium Cups From Circular Blanks With Cutouts On The Perimeter
Directory of Open Access Journals (Sweden)
Lacki P.
2015-06-01
Full Text Available Despite substantial demand for drawn parts made of high-strength sheet metal (including titanium alloys observed in the modern industry, particularly automotive and aviation, their application remains insignificant. This results from the fact that such sheet metal shows poor plasticity and its cold-forming is almost impossible. Low drawability makes it impossible to obtain even such simple shapes as spherical cups. The authors of this study developed circular sheet-metal blanks with cutouts on their perimeter. The blanks allow for cold forming of spherical cups from Ti6Al4V titanium alloy sheet metal using conventional rigid tools. The cutouts proposed in the study affect plastic strain distribution, which in turn leads to an increase in forming depth by about 30%. The numerical analysis, performed using the PamStamp 2G System software based on finite element method, was verified experimentally.
Engineering Design Handbook Rotational Molding of Plastic Powders
1975-04-15
surface finish requirements, shape, and plating bath composition and temperature. Materials include plastics, glass, wax , latex, rubber, wood, plaster...are slightly longer when using PTFE end caps, inasmuch as PTFE is a thermal insulator. Rotolining is a technique for lining hollow metal objects...aluminum, and 1 in. thick PTFE have been employed successfully. To permit resin to flow onto flange faces, end caps must have a raised or machined-out
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