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This paper studies the vibration behaviours of laminated plates with consideration of the influences of surface and interface energies. Geometric nonlinearity is taken into account in this model to obtain the results of large amplitude vibrations. Approximate closed-form solutions for simply supported plates, clamped plates and clamped circular plates are provided. Numerical results show that the surface/interface effect can affect the dynamic behaviours of laminated plates at nanometer scale. This is especially for nonlinear (large-amplitude) vibration. In addition, the ratio of the thickness to length of the plate, the external load and number of layers also affect the surface/interface effects for large amplitude vibration. This study is helpful for designing and examining the non-linear dynamic behaviour of laminated nanoplates and nanoscale devices.

The use of Pipe Belt Conveyor (PBC) has gained more and more popularity in bulk solids handling. Compared to the traditional trough conveyors, PBC can allow tighter curves and steeper gradients of conveyor routes and thus better suits the applications in difficult terrains. It has many unique mechanical characteristics which are not well understood yet. This paper proposes a coupled finite element model (FEM) and discrete element method (DEM) model to investigate the mechanics of a PBC system, with particular reference to the distribution of contact force in the pipe section. This FEM/DEM model considers comprehensively the formation of pipe from a flat belt and the microscopic structure of discrete particles under gravity, and thus can well describe the states of both conveyor belt and bulk solids. The predictions of the contact forces are shown to agree well with the previous experimental data under different conditions. Using this approach, the distribution of contact forces under different load conditions, i.e. zero gravity (ZG), empty pipe (VF 0%), volume fill of 40% (VF 40%) and 80% (VF 80%) are obtained and their dependencies on the rotation angle of pipe are investigated.

In this work, we develop a facile electro-deposition method to assemble Co ultrathin shell on the Co 3 O 4 nanowires forming Co 3 O 4 @Co core/branch arrays (CBAs). Co nanoshell of 5–10 nm is homogeneously connected with each other and forms a conductive “armor” on the Co 3 O 4 nanowires. Attractive advantages including high electronic conductivity and large porosity are combined in the designed core/branch architecture. Compared with the unmodified Co 3 O 4 nanowires, the Co 3 O 4 @Co CBAs have been demonstrated with higher capacity and better cycling stability. A specific capacity of 649 mAh g −1 is obtained for the Co 3 O 4 @Co electrode at 3 A g −1 , much higher than that (431 mAh g −1 ) of the Co 3 O 4 nanowires counterpart. In addition, after 300 cycles at 0.25 A g −1 , the Co 3 O 4 @Co electrode delivers a stable capacity of 863 mAh g −1 , better than the pristine Co 3 O 4 counterpart (686 mAh g −1 ) owing to better conductive networks and more stable electrode structure.

Using an improved multilayered plate model, the influence of surface and interface energies on the bending behaviour of laminated nanoplates is incorporated into the Kirchhoff plate theory. Governing equations taking into account the geometrical nonlinearity are obtained to study the influences of surface/interface energies. Based on the Navier and Ritz methods, closed-form solutions for both simply supported and clamped nanoplates are obtained. Numerical results for single- and multilayered nanoplates indicate that the interface effect can noticeably change the elastic behaviour of laminated plates on the nanometer scale. In addition, the flakiness ratio, external load, and number of layers also affect the surface/interface effects at large deformations. This study will be useful for the design and examination of nanoplates and nanoscale devices, especially multilayered plates at large deformations.

Polycrystalline Tb1−xDyxMnO3 (x=0.0, 0.3, 0.5, 0.6, and 0.8) were prepared by the traditional solid-phase reaction method. The XRD result shows that Tb0.4Dy0.6MnO3 may have a different structure; it has two diffraction peaks near 33.30° while other samples have three diffraction peaks at the same diffraction angle. The magnetic properties of Tb0.4Dy0.6MnO3 are also different from those of the other samples. An exchange-bias effect was observed at 5 K with the field cooling of ±5 T for Tb0.4Dy0.6MnO3. The dc and ac magnetizations as well as magnetic hysteresis measurements suggest the coexistence of antiferromagnet and ferromagnet characteristics which originate from the interplay of 3d and 4f electrons at the rare-earth sublattice and low temperature in Tb0.4Dy0.6MnO3.

Background: Pulmonary arterial hypertension (PAH) is characterized by sustained elevation of pulmonary vascular resistance resulting from endothelial and smooth muscle cell dysfunction and collagen deposition in pulmonary vascular walls. In this study, we investigated the role of the adenosine A2A receptor (A2AR) in the development of PAH by determining the effect of genetic inactivation of A2ARs on pulmonary vascular remodeling in mice. Methods and Results: We characterized hemodynamic, histological and ultrastructural changes in pulmonary vascular remodeling in A2AR knockout (KO) mice compared with their wild-type (WT) littermates after exposure to normoxia and hypoxic conditions. After exposure to normoxia, compared to WT mice, A2AR KO mice displayed: (1) increased right ventricular systolic pressures and an elevated ratio of the right ventricle over left ventricle plus septum (Fulton index), (2) increased wall area and thickness as well as enhanced smooth muscle actin immunoreactivity in pulmonary resistance vessels, (3) increased proliferating cell nuclear antigen-positive cells in pulmonary resistance vessels and (4) increased smooth muscle cells hypertrophy and collagen deposition in the adventitia of pulmonary arteriole walls as revealed by electron microscope. By contrast, histological analysis revealed no features of hypertensive nephropathy in A2AR KO mice and there was no significant difference in systemic blood pressure, and left ventricular masses among the 3 genotypes. Furthermore, following chronic exposure to hypoxia, A2AR KO mice exhibited exacerbated elevation in right ventricular systolic pressure, hypertrophy of pulmonary resistance vessels and increased cell proliferation in pulmonary resistance vessels, compared to WT littermates. Thus, genetic inactivation of A2ARs selectively produced PAH and associated increased smooth muscle proliferation and collagen deposition. Conclusions: Extracellular adenosine acting at A2ARs represents an important regulatory mechanism to control the development of PAH and pulmonary vascular remodeling.

This paper will discuss the design and construction of BESIII, which is designed to study physics in the tau-charm energy region utilizing the new high luminosity BEPCII double ring e+e- collider. The expected performance will be given based on Monte Carlo simulations and results of cosmic ray and beam tests. In BESIII, tracking and momentum measurements for charged particles are made by a cylindrical multilayer drift chamber in a 1 T superconducting solenoid. Charged particles are identified with a time-of-flight system based on plastic scintillators in conjunction with dE/dx (energy loss per unit pathlength) measurements in the drift chamber. Energies of electromagnetic showers are measured by a CsI(Tl) crystal calorimeter located inside the solenoid magnet. Muons are identified by arrays of resistive plate chambers in the steel magnetic flux return. The level 1 trigger system, Data Acquisition system and the event filter system based on networked computers will also be described., 57 pages, 75 figures

Pedestrian detection is a hot and difficulty topic in computer vision. This paper presents a zenithal pedestrian detection algorithm designed with the circular feature of pedestrian head in case of top view. It is a reliable pedestrian detection strategy for intelligent illumination control system. The active edge detection algorithm mextracts the pedestrian edge, and grads Hough transform detects the circular feature of pedestrian head. Matlab simulation experiments show that the detection method can effectively detect pedestrian and eliminate the interference. Keywords-pedestrian detection; hough transform; edge

In order to improve the performance of embedded driver fatigue monitor system, this article designed and implemented a new system based on Soc. This design adopts the ARM as the core processor which is connected to other peripheral by FPGA. The system also uses the embedded Linux to run the main algorithm which consists two Haar-Adaboost classifier to locate the eyes and classify the status of eye by support victor machine. At last by using PERCLOS standard the system will judge whether the driver is fatigue. Experimental results show that the system has a good real-time performance and the processing rate can reach 25 frames per second. Keywords-fatigue; embedded; PERCLOS; classifier

The friction and wear properties of hot-pressed Al 2 O 3 TiCCo advanced ceramics (called ATC here), which have been made by use of Al 2 O 3 and TiC powders chemically coated with a cobalt film, have been studied in this paper with the help of a pin-on-disk apparatus in a scanning election microscope. The experiments show that the friction behavior of ATC varies with different wear environments such as in air or in vacuum. Also the physical-chemistry changes at the wear interfaces have a great effect on the friction properties of the ceramics. The results also indicate that microcutting and brittle fracture are the dominant mechanisms in the wear damage of ATC materials. Powder-like and flake-like particles are the main types of wear debris during the wear process.

A series of measurements were taken in the limited hardenability bearing steel rings which were induction hardened and tempered. Measurements showed several features which strengthened the rings: (1) Compressive residual stress are generated from surface to a depth of 3.2 mm and high residual compressive stress at the location where fatigue fracture initiates. (2) The matrix of the hardened layer was composed mainly of lath martensite with dispersed carbides whose formula was Me{sub 3} according to the X-ray spectrum analysis. The carbon content of martensite was estimated to be lower than 0.58% (by weight). The core was constituted of troostite transformed from spheroidal carbide. (3) The amount of retained austenite in the hardened layer was about 5% (in volume) which ensures the high dimensional stability of bearing.

To meet with requirements of BESIII experiment, the main tracking device is a cylindrical drift chamber with small-cell geometry, using a helium-based gas and operating in a IT magnetic field. A cosmic ray test without magnetic field has been carried out. Preliminary results show that the rms of the residual distribution is 168 mum after the pre-alignment and the calibration of T0 and time-to-distance relation.

A novel digital watermaking embedding and detecting algorithm for image is presented, which uses the chrip signal as a watermark and embeds in the fractional Fourier transform (FRFT) domain of the image, and the watermark position and the transform order are used as the encryption keys. With the help of the property of the impulse characteristic in the FRFT domain for chirp signal, the watermark can be detected conveniently. The experiments results have show that the proposed algorithm not only is of good imperceptibility and security and is very robust to JPEG compression and to noise attacks, but also can provide protection under the cropping and the filtering.

Recently, the depth profile reconstruction of the thermal conductivity or diffusivity of inhomogeneous samples has attracted considerable interest [1–4]. But in most of these works, a mathematical model for unknown profiles was a prior assumed, then some parameters were adjusted to fit the measured data. Moreover, only the thermal conductivity or thermal difrusivity profile with known density and specific-heat had been investigated. An alternative method had been introduced in our previous articles [5–7], which is based on a hybrid of Newton-like iterative method and regularization method. Using this method, two different experimental techniques had been used for reconstruction theories of the thermal conductivity depth profile: (1) photoacoustic or photothermal signal with a plane heat source [5–6], (2) modulated photoreflectance technique [7] with a Gaussian pumping laser, which had demonstrated the possibility of practical application by numerical simulations with random noise.

Pure polycrystalline nickel was implanted with 150 keV carbon ions to fluences of 2 × 10 17 ions cm −2 at room temperature. Surface layer structural characterization for carbon-implanted and post-implantation heat-treated specimens, and its effect on fatigue behaviour, were investigated. The microstructural changes by the direct implantation of carbon into nickel were examined by transmission electron microscopy. It was found that the implantation results in the formation of amorphous phase, Ni 3 C compound and some other metastable phases corresponding to different depths below the surface. The crystallization temperature of amorphous NiC is about 500°. The specimens were tested under load-unload tensile fatigue. A 22% increase in endurance limit was found after implantation. Fatigue behaviour of post-implantation heat-treated specimens is the same as before implantation. The fatigue surface was examined by scanning electron microscopy. Grain boundary cracking is another crack nucleation mode of the implanted specimens besides slip band cracking which is the only crack initiation mode of pure nickel. Fatigue cracks of post-heat-treated specimens nucleate at large Ni 3 C particles. Transmission electron micrographs show that the cyclic loading leads to recrystallization of carbon-ion-induced amorphous NiC.