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The dynamic behaviors of the well-known multi-phase magneto-electro-elastic (MEE) structures usually receive much attention in designing various intelligent devices, and the finite element method (FEM) is an effective numerical procedure for MEE structural dynamics. However, the relatively high mesh quality is necessary for the FEM to generate reliable results because of the overestimation of stiffness matrices. For this reason, other powerful numerical approaches are still pursued. In present work, a coupling MEE edge-based smoothed finite element method (ES-FEM) model is established to evaluate the dynamic performance of the MEE solids. With the edge-based gradient smoothing operation, the smoothed strains, electric fields and magnetic fields are obtained. As a result, the close-to-exact system stiffness matrices are constructed. The solution precision, convergence rate and computation efficiency of the ES-FEM are carefully compared with those of the traditional FEM through several typical numerical examples, and the outstanding behaviors of the ES-FEM in free vibration analyses and harmonic response analyses of MEE structures are examined. The numerical results from the ES-FEM are still reliable even with relatively coarse spatial discretization. [ABSTRACT FROM AUTHOR]

Purpose: It is well known that the difficulties in constructing an appropriate mesh limit the performance of the traditional finite element method in practical applications. Recently, the overlapping finite element method (OFEM) has been presented to increase the efficiency of the low-order finite elements. However, more studies on the overlapping finite element in dynamic analyses are still pursued. In this paper, the OFEM is extended into the two-dimensional linear elastic solid dynamic analysis. Methods: The abilities of the OFEM in the free vibration of two-dimensional linear elastic solids are first examined. Then, the Bathe time integration method, which is a direct time integration scheme, is introduced to assess the performance of the employed element in the forced vibration analysis. Through several typical numerical examples, the accuracy of natural frequencies, convergence rate, and computational efficiency obtained from the overlapping element are evaluated. In addition, the numerical stability regarding the matrix conditioning and the sensitivity to the irregular mesh in OFEM is also studied. Results: The numerical tests demonstrate that, compared with the conventional finite elements, the overlapping elements can lead to much more precise solutions with high computation efficiency and are almost distortion insensitive. Conclusion: The OFEM is an effective method and can significantly reduce the meshing difficulties in dynamic problems, and thus can perform well in vibration analyses of complex structures.

In the analyses of transient wave propagations, a numerical method with the monotonic convergence property is favored by analysts. However, the classic finite element method does not possess this attractive property due to pronounced numerical dispersions and can generate severe spurious oscillations by using a small time step. In this work, the novel quadrilateral overlapping element is extended into the investigation of transient wave propagations by using the standard implicit Bathe time integration method. Since the local field approximation in overlapping elements can be a function, the performances of different basis functions in transient wave propagation problems are studied. Detailed analyses regarding the numerical dispersion error caused by spatial and temporal discretization are conducted. Then several numerical experiments with different types of excitation loading are investigated to show the performance of the quadrilateral overlapping elements. It is shown that the overlapping element with the trigonometric functions and the bilinear Lagrange polynomials has the monotonic convergence property and can perform well in handling various transient wave propagation problems. [ABSTRACT FROM AUTHOR]

ABSTRACTSodus tenuevittatusis removed from synonymy with Mispila(s. str.) venosaand considered as bona species: Mispila(s. str.) tenuevittatacomb. nov. The following synonymies are proposed: Mispila tenuevittata = Mispila(Dryusa) sonthianaesyn. nov. and Mispila(s. str.) tonkinea= Mispila(s. str.) punctifronssyn. nov. New distributional records for M. tenuevittataand M. tonkineaare provided. The lectotypes of M. venosaand M. tonkineaare designated.

We are concerned with global solutions of multidimensional (M-D) Riemann problems for nonlinear hyperbolic systems of conservation laws, focusing on their global configurations and structures. We present some recent developments in the rigorous analysis of two-dimensional (2-D) Riemann problems involving transonic shock waves through several prototypes of hyperbolic systems of conservation laws and discuss some further M-D Riemann problems and related problems for nonlinear partial differential equations. In particular, we present four different 2-D Riemann problems through these prototypes of hyperbolic systems and show how these Riemann problems can be reformulated/solved as free boundary problems with transonic shock waves as free boundaries for the corresponding nonlinear conservation laws of mixed elliptic-hyperbolic type and related nonlinear partial differential equations.

ABSTRACT Segments of corroded plain reinforcing bars were firstly extracted from an aged reinforced concrete (RC) pole after its breaking. The testing specimens were then taken from these segments. The [...]

Glyphosate (GP) has given rise to concerns regarding its environmental impact and potential hazards to human health. Herein, a solvothermal approach was used for doping Co and Zr into Fe3O4, thereby endowing the adsorption and catalytic efficacy for GP elimination and phosphate recovery from aqueous solution. The magnetic nanoparticles achieved 100 % removal of 100 mg/L GP in 30 min with 0.5 mM peroxymonosulfate (PMS). Electron paramagnetic resonance (EPR) test verified that both radical and non-radical pathways were produced in the catalytic oxidation process. Density functional theory (DFT) investigations have demonstrated that Co and Zr co-doping led to an improved removal efficiency of GP. Moreover, the as-prepared material used in this integrated PMS activation and adsorption maintained a high stability towards GP degradation and phosphate recovery during five successive cycles. This study provides an efficient technique for the removal of GP and the simultaneous adsorption of secondary inorganic phosphorus from water.

In acoustic analyses the standard radial point interpolation meshless method (RPIM) is able to outperform the classic finite element method (FEM) because the numerical dispersion can be significantly mitigated by increasing the size of the interpolation domain. However, this operation usually leads to a surge in computational cost. In this work an enriched RPIM (e-RPIM) is developed by using the general multiple wave patterns but no extra degrees of freedom are needed. In this enriched scheme the traditional radial basis function interpolation is augmented by a set of plane wave enrichment functions which helps to reflect the oscillation characteristics of the wave propagation. This e-RPIM can obviously alleviate the numerical dispersion and yield satisfactory solution accuracy by using a relatively small size interpolation domain. Although extra computational cost is required in constructing the enriched interpolation shape functions, the computational efficiency of the original RPIM is evidently improved by the proposed e-RPIM if the computation accuracy is taken into consideration. Several numerical experiments validate that the proposed e-RPIM is a promising competitor to the standard RPIM and FEM in acoustic analyses. [ABSTRACT FROM AUTHOR]

We present a bionic neural wave network that uses multiple autonomous underwater vehicles to search and acquire intelligent targets in an unknown underwater environment. The neuron pheromone content is arranged according to neural wave diffusion and layer-by-layer energy attenuation, when underwater mesh space based on neural wave diffusion theory was established that the neuron nodes in the neural network structure correspond to obstacles, autonomous underwater vehicles, and targets in the environment. In order to solve the problems of over-allocation and under-allocation of the multi-autonomous underwater vehicles system during the cooperative capture of targets, a redistribution mechanism based on the improved self-organizing map algorithm is implemented and directed to rationalize task distribution. Two different taboo search methods are employed to update the autonomous underwater vehicle path in real time, and the polynomial coefficient solution method is used to fit partial path data. So that the autonomous underwater vehicle trajectory can be obtained and an interceptor position coordinate can be predicted. An auxiliary autonomous underwater vehicle is aimed to replace the intercepted autonomous underwater vehicle and the matching capture points are tracked to ensure the completion of the task so that the full range of hunting targets is identified. In order to simulate an unknown complex underwater environment, obstacles are randomly arranged around the target, the location information of the obstacle, and the target is unknown and unpredictable. Four simulation experiments were performed to verify the accuracy and efficiency of the algorithm under unknown environment. The results show that this algorithm can improve the path update average efficiency by 66% compared with other algorithms. Obviously, this algorithm is reasonable and effective.

•Therapy combined with UDCA, prednisolone and immunosuppressants is more effectivity than UDCA monotherapy for PBC patients.•The improvements are mainly focus on liver biochemical parameters, immune indicators and noninvasive fibrosis indicators.•Anti-gp210 antibody positivity, AMA negativity, high ALP, TBIL and globulin levels and severe degree of fibrosis at baseline were associated with poor prognosis.•The triple therapy may be a rescue therapy for refractory PBC patients.

To explore the efficacy treatment regimen in refractory PBC.

Treatment with combined sofosbuvir and velpatasvir has resulted in high sustained virological response rates in patients chronically infected with hepatitis C virus (HCV) with genotypes 1–6 in clinical trials and real-world settings, but its efficacy and safety has not been assessed in Asia, a region with diverse HCV genotypes.

This study investigated the durability properties of structural concretes incorporating secondary cementitious materials of fly ash and ground granulated blast-furnace slag (GGBS). The compressive strength and porosity were taken as basic properties, and the transport properties measured included electrical conductivity, chloride diffusivity, capillary absorption and gas permeability. Correlation analysis was performed on the basic and transport properties, and the pore structure of structural concretes was characterized into different patterns in terms of the connectivity and the tortuosity. The results show that (a) the concrete pores are refined by mineral admixtures and Archie’s law can describe the pore connectivity and tortuosity for saturated specimens; (b) all the transport properties correlate well with water-to-binder (w/b) ratios and the concretes with GGBS show a pronounced effect of oven-drying and self-desiccation on pore structure; and (c) chloride diffusivity and surface sorptivity correlate better with compressive strength, while chloride diffusivity, sorptivity and gas permeability should be treated as independent properties.

We are concerned with the stability of steady multi-wave configurations for the full Euler equations of compressible fluid flow. In this paper, we focus on the stability of steady four-wave configurations that are the solutions of the Riemann problem in the flow direction, consisting of two shocks, one vortex sheet, and one entropy wave, which is one of the core multi-wave configurations for the two-dimensional Euler equations. It is proved that such steady four-wave configurations in supersonic flow are stable in structure globally, even under the BV perturbation of the incoming flow in the flow direction. In order to achieve this, we first formulate the problem as the Cauchy problem (initial value problem) in the flow direction, and then develop a modified Glimm difference scheme and identify a Glimm-type functional to obtain the required BV estimates by tracing the interactions not only between the strong shocks and weak waves, but also between the strong vortex sheet/entropy wave and weak waves. The key feature of the Euler equations is that the reflection coefficient is always less than $1$, when a weak wave of different family interacts with the strong vortex sheet/entropy wave or the shock wave, which is crucial to guarantee that the Glimm functional is decreasing. Then these estimates are employed to establish the convergence of the approximate solutions to a global entropy solution, close to the background solution of steady four-wave configuration.

Superplastic forming/diffusion bonding (SPF/DB) process is widely used in aviation titanium alloy parts forming. PAM-STAMP was utilized to simulate the SPF/DB process of a Ti-6Al-4V double layer structure part in rear fuselage at 920°C and reach the thickness distribution of the part. Then the part was formed based on simulation. The thickness distribution of the practical part was measured and compared with the simulation result. The results show that the thickness distributions of practical and simulated part fit well with each other.

The first domestic inorganic scintillator, Cs2LiYCl6:Ce3+(CLYC), was grown at Beijing Glass Research Institute using the vertical Bridgman method. In this work, we evaluated the performance of this new CLYC crystal in terms of its gamma-ray energy resolution and pulse shape discrimination (PSD) capability between neutrons and gamma rays. The decay times associated with different scintillation mechanisms were obtained by fitting decay functions to the neutron and gamma-ray waveform structures. We found an energy resolution of ~ 4.5% for 662-keV gamma rays and efficient neutron/gamma PSD with a figure of merit of ~ 2.6. Under gamma-ray excitation, there is an ultrafast scintillation mechanism in CLYC with a decay time of approximately 2 ns, whereas there is no evidence of ultrafast decay under thermal neutron excitation. This work contributes to the promotion of domestic development of CLYC.

When an upstream steady uniform supersonic flow impinges onto a symmetric straight-sided wedge, governed by the Euler equations, there are two possible steady oblique shock configurations if the wedge angle is less than the detachment angle—the steady weak shock with supersonic or subsonic downstream flow (determined by the wedge angle that is less than or greater than the sonic angle) and the steady strong shock with subsonic downstream flow, both of which satisfy the entropy condition. The fundamental issue—whether one or both of the steady weak and strong shocks are physically admissible solutions—has been vigorously debated over the past eight decades. In this paper, we survey some recent developments on the stability analysis of the steady shock solutions in both the steady and dynamic regimes. For the static stability, we first show how the stability problem can be formulated as an initial-boundary value type problem and then reformulate it into a free boundary problem when the perturbation of both the upstream steady supersonic flow and the wedge boundary are suitably regular and small, and we finally present some recent results on the static stability of the steady supersonic and transonic shocks. For the dynamic stability for potential flow, we first show how the stability problem can be formulated as an initial-boundary value problem and then use the self-similarity of the problem to reduce it into a boundary value problem and further reformulate it into a free boundary problem, and we finally survey some recent developments in solving this free boundary problem for the existence of the Prandtl-Meyer configurations that tend to the steady weak supersonic or transonic oblique shock solutions as time goes to infinity. Some further developments and mathematical challenges in this direction are also discussed.

Electro-deposition, electrical activation, thermal oxidation, and reactive ion sputtering are the four primary methods to fabricate iridium oxide film. Among these methods, reactive ion sputtering is a commonly used method in standard micro-fabrication processes. In different sputtering conditions, the component, texture, and electrochemistry character of iridium oxide varies considerably. To fabricate the iridium oxide film compatible with the wafer-level processing of neural electrodes, the quality of iridium oxide film must be able to withstand the mechanical and chemical impact of post-processing, and simultaneously achieve good performance as a neural electrode. In this study, parameters of sputtering were researched and developed to achieve a balance between mechanical stability and good electrochemical characteristics of iridium oxide film on electrode. Iridium oxide fabricating process combined with fabrication flow of silicon electrodes, at wafer-level, is introduced to produce silicon based planar iridium oxide neural electrodes. Compared with bare gold electrodes, iridium oxide electrodes fabricated with this method exhibit particularly good electrochemical stability, low impedance of 386 kΩ at 1 kHz, high safe charge storage capacity of 3.2 mC/cm2, and good impedance consistency of less than 25% fluctuation.

The principle of measuring cellular glass by automatic densimeter was studied. The effect of pressure on closed cell content was researched in order to optimize the measuring pressure. The influence of closed cell content on the insulation property was analyzed by measuring thermal conductivity. The results showed that cell structure of cellular glass can distort or even be damaged with the increasing of pressure and the first condition for obtaining accurate closed cell content was to optimize the measuring condition and determine appropriate pressure. Closed cell content affects the insulation property of the cellular glass significantly.

A novel linear microprobe array (LMPA) has been developed by a conventional microfabrication method from silicon. The LMPA leverages the properties of conventional microwire with additional features of naturally formed regular spacing. With the help of periodic microprobe arrays and double-side V-grooves fabricated in advance between each pair of the two microprobes’ rear ends, the number of microprobe units for assembly in one array can be flexibly chosen by cleavage fracture from the LMPA. The fabrication method was demonstrated and the prototype device was assessed by electrochemical impedance spectroscopy (EIS) and in vivotest. The SNR of the spikes recorded was 6.

In order to improve the diagnosis rate of wavelet neural network algorithm for the radar circuit, for the network during operation there is poor convergence, the training error and shortcomings easy to fall into local minimum, the network is unable to continue training and testing, proposing a new algorithm of increasing the momentum of the wavelet adaptive neural network, can make the network run more stable, faster learning rate; By the Matlab simulation experiments show that the diagnosis rate of the improved algorithm is much higher than the ordinary one.

The selection of suppliers is very important in the purchase of decision support systems. In this paper, firstly the complicated factors of supplier selection which existed in the course of purchase inviting bid are analyzed systemically, Then an comprehensive evaluation index system for picking up the ideal bidders is put forward, Based on the hierarchy-gray theory, a multi-attribute decision mathematics model of purchase inviting bid is constructed, Finally feasibility and effectiveness of the model is testified by a example.

In this study, data from 244 CBM production wells were collected and analyzed in China. Based on the data, coalbed methane (CBM) reservoir properties and geological factors were studied. Combined with previous study results, the current situation of CBM resource evaluation, the classification of evaluation indexes and evaluation standard were analyzed. Finally, the evaluation system aiming at deep coal seam CBM was suggested. This system tries to provide important theoretical and technical support to CBM exploration and geological target selection evaluation for deep coal seams in China. This will provide important guideline and technical support to CBM exploration and geological target selection evaluation in deep coal seam CBM in China.

This paper presents a mathematical method to analyze the influence of each machine tool part deformation on the machining accuracy. Taking a 3-axis machine tool as an example, this paper divides the machine tool into the cutting tool sub-system and workpiece sub-system. Taking the deformation of lower surface of the machine bed as the research target, the mathematical model of the deformation on the displacement of the cutting point was established. In order to distribute the stiffness of each part, the contribution degree of each part on the machining accuracy was analyzed. Using this mathematical model, the stiffness of each part can be distributed at the design stage of the machine tool, and the machining accuracy of the machine tool can be improved economically.

Multi-electrode array is an important tool in the study of neural-network, cognition, remembrance, as well as brain-computer-interface, etc. Fork-like 32-site microelectrodes are developed with silicon. By use of integrated circuit technology, the length of the electrodes, the area of the recording sites, as well as the spaces between the sites are closely controlled. SiO2/SiNx/SiO2composite dielectric membrane and Pt black are introduced to improve the characteristics of the electrodes. The whole thickness of the thin-film probe was 21 μm. By combining the modifying process with the micro-fabrication method, this kind of silicon based microelectrode satisfies high-density recording and the performance characterization is evaluated by test in vitroand in vivo.

In this paper, a novel metal structure that integrates double continuous Au films and double aligned gold (Au) non-close-packed ellipsoidal nanoparticle arrays is proposed. The optical features of this structure are simulated by using the three-dimensional finite-difference time-domain (3D-FDTD) method. Bimodal plasmonic resonances with the highest transmission up to 74% and 66% (corresponding to the short and long-wavelength, respectively) are achieved. This proposed structure with sub-wavelength size may provide fascinating applications in optoelectronic devices such as transparent conductors and conductive devices, slow light devices, highly sensitive sensors.

A novel plasmonic passband filter consisting of metal-insulator-metal perforated with an array of rectangular grooves and circular holes is proposed and demonstrated. The transmission property of the proposed structure is obtained by employing the finite difference time domain with perfectly matched layer absorbing boundary condition. The result reveals that a passband with high transmission can be achieved. And the transmission peak position can be efficiently tuned by changing the factors of the structure, such as the sizes of circular holes and grooves. The proposed filter has potential applications for integrated optoelectronic devices due to its miniaturized size.

We propose and theoretically study a novel plasmonic nanostructure composed of two malposed silver (Ag) triangular nanocylinder arrays by the finite-difference time-domain (FDTD) method. The excitation of the localized surface plasmons (LSPs) of the metal triangular nanocylinders, and the strong interaction coupling between LSPs contribute to the enhanced transparency in the visible and near-in region (NIR). The transparency response in the proposed nanostructure is modified by changing the gap distances between two adjacent triangular nanocylinders, and the dielectric environments. The tunable enhanced optical transparency of the proposed nanostructure provides potential applications in sensors and plasmonic filters.

In this paper, using finite element software ANSYSanalyzes seismic respons of Fuyang river aqueduct, respectively establishfinite element model under viscoelastic boundary conditions and elasticboundary conditions, compare and analyze seismic respons of aqueduct structureunder two kinds of boundary conditions. The results show that, compared withelastic boundary conditions, viscoelastic boundary conditions not only cansimulate elastic recovery performance of foundation, but also can realizeinfinite medium radiation damping, and viscoelastic boundary conditions is moreclose to the actual situation.

A prototype of hybrid neural recording interface has been developed for extracellular neural recording. It consists of a silicon-based plane microelectrode array and a CMOS low noise neural amplifier chip. The neural amplifier chip is designed and implemented in 0.18 μm N-well CMOS 1P6M technology. The area of the neural preamplifier is only 0.042 mm2with a gain of 48.3 dB. The input equivalent noise is 4.73 μVrms within pass bands of 4 kHz. To avoid cable tethering for high dense multichannel neural recording interface and make it compact, flip-chip bonding is used to integrate the preamplifier chip and the microelectrode together. The hybrid device measures 3 mm×5.5 mm×330 μm, which is convenient for implant or in-vivoneural recording. The hybrid device was testified in in-vivoexperiment. Neural signals were recorded from hippocampus region of anesthetized Sprague Dawley rats successfully.

We are concerned with free boundary problems arising from the analysis of multidimensional transonic shock waves for the Euler equations in compressible fluid dynamics. In this expository paper, we survey some recent developments in the analysis of multidimensional transonic shock waves and corresponding free boundary problems for the compressible Euler equations and related nonlinear partial differential equations (PDEs) of mixed type. The nonlinear PDEs under our analysis include the steady Euler equations for potential flow, the steady full Euler equations, the unsteady Euler equations for potential flow, and related nonlinear PDEs of mixed elliptic–hyperbolic type. The transonic shock problems include the problem of steady transonic flow past solid wedges, the von Neumann problem for shock reflection–diffraction, and the Prandtl–Meyer problem for unsteady supersonic flow onto solid wedges. We first show how these longstanding multidimensional transonic shock problems can be formulated as free boundary problems for the compressible Euler equations and related nonlinear PDEs of mixed type. Then we present an effective nonlinear method and related ideas and techniques to solve these free boundary problems. The method, ideas, and techniques should be useful to analyze other longstanding and newly emerging free boundary problems for nonlinear PDEs.

Zeolitic imidazolate frameworks-8(ZIF-8, Zn (MIM) 2, MIM=2-methylimidazole) was synthesized by solvothermal (S) method and liquid-phase diffusion (D) method. ZIF-8 was then directly impregnated with phosphortungstic acid (PTA) at room temperature. After impregnation, the ZIF-8 retained its integrity of frameworks as proved by several characterizations. The textural properties are heavily dependent on preparation methods. Diffusion method produced well-crystallized particles with larger surface area, whereas solvothermal method yielded poorly-crystallized particles. ZIF-8 and ZIF-8-PTA were applied in the photo-degradation of methylene blue (MB) with the assistance of electron acceptor hydrogen peroxide, in which both of them were found to be highly active photo-catalytic. Moreover, the impregnation of PTA improved clearly the activity of catalysts due to the fast reversible multi-electron redox transformations.

We presented a new framework for dynamic level of detail rendering of multi-models. Our framework adopts LOD control on every single model, and keeps low screen errors. Firstly, we introduce a new simple and efficient implementation of PM which is used to save memory and CPU resource. Secondly, we try to optimize all models by combining progressive mesh with occlusion culling. At last, we promote a view-dependent level of detail rendering system by technics such as frustum culling, LOD control, reservation of resource, GPU cache and so on. Experiments show that this simple framework which is named PM-OCMMRF (Progressive Mesh-Occlusion Culling combined Multi-Models Rendering Framework) values a lot in applications of rendering multi-models.

Geometric errors of a machining center can cause great influence on machining accuracy, and these geometric errors should be identified and compensated in the actual working conditions. Taking a three-axis vertical machining center as example, 21 geometric errors of the machine tool were solved. By using the 12-line method based on a laser interferometer, identification principle of the positioning errors, straightness errors, pitch errors, yaw errors, roll errors and squareness errors are presented, and all of the 21 geometric errors of the machining center were identified. Geometric errors having great influence effect on machining accuracy can be identified. The research results provide guidance for analyze of geometric errors of machining center.

In order to improve machining accuracy of machining center, the effect of geometric error on machining accuracy was researched by multi-body system theory. Taking a vertical machining center as example, topological structure of the machining center was described by lower body array. Geometric errors of the bodies in the multi-body system were expressed by homogeneous coordinate transformation. Error model for machining accuracy was deduced and geometric errors having great influence on the machining accuracy were identified. The research results show that, straightness errors and linear displacement errors in three directions have direct influence on machining accuracy, and the effect on machining accuracy caused by angle errors are related to the dimensions of the machining center and travel distance of the three axes. The research results provide guidance for analysis on sensitivity of geometric errors.

The effect of geometric error on machining accuracy was researched by multi-body system theory, as well as homogeneous coordinate transformation method. Taking a vertical machining center as example, topological structure of the machine tool was described by lower body array. Lower body array of the machining center, motion freedom between adjacent bodies and geometric errors of the vertical machining center were analyzed. Geometric errors of the bodies in the multi-body system were expressed by homogeneous coordinate transformation. Error model for machining accuracy was deduced and geometric errors having influence on the machining accuracy were identified. The research results provide guidance for analyze of geometric errors on machining accuracy.

In order to get an accurate analysis results for static and modal characteristics of a machining center, finite element analysis method was taken. Taking a horizontal machining center as example, solid model was established firstly. Finite element model containing joint parameters was established in ANSYS. With the help of finite element method, static and modal characteristics of the horizontal machining center were carried out. It was concluded that the horizontal machining center has comparatively smaller static stiffness in Z direction; in order to improve modal characteristic of the horizontal machining center, the column and worktable should be paid more attention. The research results provide guidance for finite element analysis and optimization of whole machine tool.

A series of waterborne cationic polyurethanes dispersions (CWPU) was prepared through prepolymerization method by reacting polyethylene glycol (PEG1000) and isophorone diisocyanate (IPDI) with N-methyl diethanol amine (MDEA) as chain extender. Then FeCl3 was employed as oxidant, therefore CWPU/polypyrrole (CWPU/PPy) conductive composite was prepared by in situ chemical oxidative polymerization of pyrrole (Py) in CWPU dispersions. Effects of molar ratio of FeCl3 to Py, Py concentration on the resistivity of the CWPU/PPy composite films were investigated. The structure, morphology and thermal stability were also characterized by Fourier infrared spectra (FT-IR), light scattering, TEM, and TGA. FT-IR demonstrated the presence of hydrogen-bonding interactions between CWPU and PPy. The average particle size of CWPU/PPy increased from 10.61nm to 30.29nm compared with pure PU, and corresponding size distribution decreased from 0.850 to 0.346. It was also found that CWPU/PPy displayed as spherical morphology, and no aggregation among particles was detected among particles. TGA certified CWPU/PPy was endowed with better thermal stability. In addition, conductivity stability of composites films was also studied. It was found that composite films not only displayed low resistivity but also improved conductivity stability.

The performance of diesel’s fuel-supply system is the key to ensuring the normal operation of diesel and there are many kinds of causes to the same fault phenomenon. In order to ensure the sound performance of the diesel, the fuel-supply system of diesel is made research of as the main object. The components of the fuel-supply system, common fault of the components and the fault-detection methods are analyzed. What’s more, the common fault phenomenon and fault-elimination methods are further analyzed. Emergent treatment to system fault is set forth so as to improve the efficiency in the process of equipment maintenance, reduce the time consumption of maintenance and finally achieve the purpose of reducing costs.

Abstract In the present study, an attempt has been made to investigate the effect of cutting parameters (cutting speed, feed rate and depth of cut) on cutting forces (feed force, thrust force and cutting force) and surface roughness in milling of Quartz glas using diamond wheel. The cutting process in the up-cut milling of glass is discussed and the cutting force measured. The cutting force gradually increases with the cutter rotation at the beginning of the cut, and oscillates about a constant mean value after a certain undeformed chip thickness. The results show that cutting forces and surface roughness do not vary much with experimental cutting speed in the range of 55–93 m/min. The suggested models of cutting forces and surface roughness and adequately map within the limits of the cutting parameters considered.

After while the “Human Genome Project” proposes, the people complete measures the foreword plan after the multi-gene genome team, also starts to change to these genes and their reciprocity function understanding research. Varieties of gene regulation Boolean networks algorithms have been proposed of the gene expression profiles, however, the problem of noise could always be found in creating a Boolean network. Due to gene expression data are always noisy. In this paper, it show that after the Boolean networks logic function are learned from noisy data, some noise in the Boolean function could be restructure Karnaugh Maps. It could find logic relationships between protein and protein and restructure protein logic networks. It find logic relationship among proteins as well as COGs (clusters of orthogous groups) and build the logic network of protein.

Abstract: Silicon-based planar neuroprobes are composed of silicon substrate, conducting layer, and insulation layers of SiO2 or SiN membrane. The insulation layer is very important because it affects many key parameters of neuprobes, like impedance, SNR (signal noise ratio), reliability, etc. Monolayer membrane of SiO2 or SiN are not good choices for insulation layer, since defects and residual stress in these layers can induce bad passivation. In this paper a composite insulation structure is studied, with thermal SiO2 as the lower insulation layer and with multilayer membrane composed of PECVD SiO2 and SiN as the upper insulation layer. This structure not only solves the problem of residual stress but also ensures a good probe passivation. So it’s a good choice for insulation layer of neuroprobes.

Variable temperature kinetics under different heating rates for the Fe-based amorphous ribbons are studied by differential scanning calorimeter (DSC) technology. The results show that imported and domestic amorphous ribbons have the same overheating degree under the same heating rate, and the initial crystallization temperature is proportional to the cube root of the heating rate. The calculation indicate that the crystallization activation energy of imported and domestic amorphous ribbons are about 297~300 kJ/mol and 335~340 kJ/mol, respectively.

High volume fraction silicon carbide particulate reinforced aluminum matrix (SiCp/Al) composite are new class of difficult-to-machine materials due to their high strength. This paper presents an experimental investigation on the machinability of 60 vol% SiCp/Al composites by comparing the rotary ultrasonic milling method with the conventional machining method. The test scheme is designed, and the measurement method of the cutting force, surface roughness and morphology are illustrated. Based on the constructed experimental platform, the influences of machining parameters, such as cutting speed, feed rate and cut depth, on the cutting force and surface roughness are discussed. The experimental results show that ultrasonic machining is an effective method for machining high volume fraction SiCp/Al.

In order to combine rugged terrain and abuttals efficiently and accurately in current GIS, an improved method is presented which realized abuttals rendering on rugged terrain by the way of combining buffer object and ZP+ algorithm which comes from Z-pass. We create the shadow volume via extruding abuttal data, then play real-time rendering ,determine the width of shadow volume dynamically using screen-space error metric, as a result, the volume could fit the scene closely. For improving the render rate we store the volume vertex arrays using buffer object. Experiments indicate that the method advances the program performance, combines abuttals and terrain closely and meets the demand of display.

Abstract: In this paper, a silicon-based neural probe with microfluidic channels was developed and evaluated. The probe can deliver chemicals or drugs to the target neurons while simultaneously recording the electrical action of these neurons extracellularly. The probe was fabricated by double-sided deep reactive ion etching (DRIE) from a silicon-on-insulator (SOI) wafer. The fluidic channels were formed with V-shape groove etching on the silicon probe and sealed with silicon nitride and parylene-C. The shank of the probe is 4 mm long and 120 μm wide. The thickness of the probe is 100 μm. The probe has two fluidic channels and two recording sites. The microfluidic channels can withstand a pressure drop as much as 30 kPa and the flow resistivity of the microfluidic channel is 0.13 μL min-1 kPa-1. The typical impedance of the neural electrode is 32.3 kΩ at 1 kHz at room temperature.