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Linear segregation of high strength aluminum alloy ZL205A castings were studied by X-ray Nondestructive testing, scanning electron microscope and energy dispersive spectrometer. It is found that the linear segregation occurs at the large wall thickness of the casting and/or at the place where the wall thickness is in transition. Segregation element is mainly Cu, which exists as compound θ (Al2Cu) phase. The formation of linear segregation is related to the flow of Cu-rich melt in the late solidification period, while the occurrence of thermal cracks promotes the formation of linear segregation. The formation of linear segregation of the casting can be effectively prevented by eliminating hot spots of the casting, refining crystal grains and increasing solidification speed of the casting.

Lightweight porous metals are focused on as energy absorbing materials for automobiles. Open-cell porous metals were manufactured through additive manufacturing process. Their cell structures were designed based on Voronoi diagrams using a commercial 3D-CAD software. Both ordered and disordered cell structures with the same porosities were successfully designed in this study. Compression tests and explicit finite element analysis revealed heterogeneous deformation behaviors in ordered porous metals. On the other hand, the porous metals with disordered cell structure showed relatively isotropic and uniform deformation, which is suitable as energy absorbing materials. Controlling the disordered cell structure designed by 3D-Voronoi diagram enables to develop the advanced porous metals having various mechanical properties.

To address stringent performance and reliability requirements of industrial and traction power conversion systems we have developed planar 3,300V MOSFETs at a 6-inch SiC-compatible silicon CMOS foundry. By optimizing the unit cell structure and using a deep current-spreading layer we demonstrated a low MOSFET specific on-resistance RDSA=11.2 mΩ·cm2(ID=5A, VGS=15V) and fast switching for the baseline design. Robust short-circuit handling (7.5μs at Vds=1500V and 5.0μs at Vds=2200V) was demonstrated with an alternative unit cell design with RDSA=14.8 mΩ·cm2(ID=5A, VGS=15V).

In-suit β-Ti (Zr,Nb) dendrite/amorphous matrix composites were prepared by copper injection casting, specimens (1.5:1 aspect ratio) with different diameters were tested under quasi-static compressive loading at different strain rate. The results show that the structure of amorphous composites is amorphous matrix and in-suit β dendritic crystal phase; for 3mm and 4mm specimens, with the change of strain rate, the compressive strength and the fracture strain have no obvious changes. however, positive strain rate sensitivity was observed to 5mm specimens; in the same strain rate, with the decrease of the diameters, compressive strength and fracture strain all have great increases, which indicate the amorphous composites has obvious size effect.

As the rapid development of network, the requirement of network measurement becomes various and the results of network measurement are applied in many fields including anomaly detection, accounting, network management etc. But the measurement resources are limit and the measurement tools or algorithms are not flexible. So how to support the diversity of network measurement requirements must be studied. With reference to the SDM, this paper proposes a novel hierarchical measurement structure including three layers and provides the network measurement reconfiguration model (NMRM).The NMRM decouples the measurement requirement from the measurement resources and supplies an ability of reconfiguration of network measurement by composing the measurement resources according to some measurement requirement dynamically. The NMRM can support flexible, dynamic and concurrent measurement in the network.

Shape memory effect and corrosion resistance of the as-cast Fe-Mn-Si based alloy were studied in this paper. The results showed that the shape memory effect of alloy would decline with the specimen size increasing. Due to the ε martensites distributed in a single direction mostly and uniformly were not prone to the phenomenon of cross-crossing at the small size interface. The corrosion resistance of the as-cast decreased as the concentration of medium increasing. Because of the Cl-, which was easily absorbed by the substrate in the HCl solution, can penetrate the surface of the substrate film and generate the soluble compound, which leads the corrosion resistance performance poorer than that in NaOH solution. Under high temperature and pressure, the average corrosion rate of the Fe-Mn-Si-based shape memory alloy was significantly lower than that of the 304 stainless steel, and its corrosion rate changed little. Because the amount of harmful impurity elements and the carbon content is low in the shape memory alloy matrix, and the film formed on the surface of the alloy is more stable, denser so as to an unobvious pitting behavior.

This paper analyzed the corrosion environment of Missan oilfields and investigated the oilfield country tubular goods used in other similar oilfields. Summarized the effect of partial pressure ratio of H2S/CO2 and Cl-to the corrosion behavior of OCTG. This paper concluded the service condition, test results and anti-corrosion mechanism of carbon steel, low-chrome steel, modified martensitic stainless steel and nickel alloy. Finally arrived at conclusion that the nickel alloy can meet the requirement of Missan oilfields, some literature reported that the modified martensitic stainless steel can apply in H2S/CO2 environment. In the condition that be easy to replace the tubular, carbon steel and low-chrome steel tubular can meet the requirement with corrosion inhibitor.

An adaptive fuzzy proportional-integral-derivative (PID) force control strategy for a prosthetic hand is presented. The classical PID controller is also applied on the prosthetic hand as comparison. The parameters of PID controller are firstly tuned by Cut and Try method. Then a fuzzy logic system is used to adjust those parameters on line. Real-time force control experiments are realized on LabVIEW and PXI (PCI eXtensions for Instrumentation) real-time (RT) platforms. A rigid object and a compliant object are grasped by the prosthesis respectively to test the performance of controllers. Experimental results indicate that the adaptive fuzzy PID force controller is more effective than PID controller.

Capturing good videos outdoors can be challenging due to harsh lighting, unpredictable scene changes, and most relevant to this work, dynamic weather. Particulate weather, if there were a heavy snow in monitor scene, it would create complex flickering effects that are irritating to people and confusing to computer vision algorithms. The research direction of video image background estimation and background estimation in heavy snow is to improve the visualization of surveillance video, especially to reduce the affection of snowflake in heavy snow. This algorithm can remove snowflakes and retain non-snowflakes moving targets we interested in. We propose a snow removal method of the pixels affected by snowflakes based on probability estimation of snowflakes detected. Firstly, we detect the snowflakes based on the optical of snowflake and time difference method. Then we estimated the coverage rate of snowflakes based on the detecting result. Finally, we build an adaptive estimation method of background pixels value based on the information feedback of snow detection and the model of pixels value. The calculation of this method is simple and the method has good processing results.

In order to improve the performance of muti-digital rights protection, a multiple watermarking algorithm based on Discrete Cosine Transform (DCT) and spread-spectrum technique is proposed. First, the host image is divided into subblock and each block is manipulated by DCT. Second, two watermarks are encrypted by Arnold scrambling. Third, the watermarks are modulated by by utilizing two kinds of strategies, and then are embedded in middle frequency coefficients of DCT domain. Experimental results show that the proposed algorithm is efficient to resist traditional signal processing attacks and has better security and robustness, higher capacity.

The capability-oriented requirements elicitation is an emerging research topic of requirements engineering, especially for complex system such as the C4ISR system. One of the problems is that the capability requirements are usually articulated in natural languages and need to be formally specified to support enterprise architecture analysis. The paper proposes a framework for modeling the domain requirements of C4ISR capabilities and suggests an extended UML modeling technique. As the modeling framework accords with the standard DoD Architecture Framework, the proposed method may populate C4ISR architectural analysis.

In order to enhance the accuracy of gait recognition, a new gait feature extraction algorithm is proposed. Firstly, the gait images are preprocessed to extract moving objects, including background modeling, moving object extracting and morphological processing. Secondly, an equidistant slicing curve model based on system of polar coordinate is designed to slice the moving object, and the slicing vector is used to describe the spatial feature; Thirdly, the slicing vector is converted into frequency signal by Fourier transform to extract the frequency feature. Finally, the above two features are fused and used for the classification. The experimental results show that proposed algorithm provides higher correct classification rate than the algorithms using single feature, and meets the requirements of the real-time.

Because both of the volume and the weight of the photoelectric platform are small, the structure of two frames and two axes is used in the photoelectric platform. As the key component of the photoelectric platform, the main frame should have sufficient strength and rigidity. In order to achieve this object, three-dimensional entity model of the main frame is established using CATIA software. Then the finite-element analysis of the model is finished with ANSYS Workbench. Based on the analysis results, the weak links of the main frame is found. Then these links are improved and the main frame is analyzed again. After improving the structure, the results of the finite-element analysis show that the main frame meets the requirements of design and has perfect overall performance.

We established a calculation model for retaining structures with double-row piles by using the midas GTS finite-element software, considering the interaction between pile and soil and adopting the contact element method, on the basis of a practical engineering application. We then determined a reasonable elastic modulus of reinforced soil bodies, thereby enabling the study of the influences of the reinforcement depth and width in the interpile soil on the internal force and displacement of the retaining structure with double-row piles. We present suggestions for reinforcement depth and width. The study results provide valuable reference for engineering design, construction, and cost control.

Security vulnerabilities and the slow speed of traditional Digital Rights Management (DRM) in E-Paper device are the major restrictions of E-Paper industry. This paper introduces a new type of E-Paper controller which is integrated with DRM. DRM is realized in hardware. Data stored in main memory and controller memory or transferred from CPU to controller are encrypted. So that so they are more secure. Display process and decryption process are combined into one pipeline and can run simultaneously. Thus higher speed and less security vulnerabilities are given to controller.

Superplasticity is a physical phenomenon associated with certain polycrystalline materials which exhibit very high tensile elongation prior to fracture under particular conditions of strain rate and temperature. Aluminium alloy undergoes superplastic elongation in the order of a few thousands percent in elongation with low flow stresses. Superplastic forming processes can provide products with integral structure, light weight and superior strength, all of which are of particular importance for aerospace and automotive components. In the present study an analytical model was developed for a rectangular component by considering constant strain rate. This paper attempts to explore the superplastic behaviors of 8090 Al-Li alloy sheet into a rectangular die using blow forming technique. This has been done by a simple theoretical model and by numerical simulation using standard finite element code ABAQUS. The numerical and analytical results agree reasonably well for both the analytical and theoretical values with regard to variation in pressure and time.

Hydroforming is one of the forming technique which paves the way for the easy production of light weight and high strength automotive and aerospace components. The different approaches presented by the various authors in the field of hydroforming and its applications are reviewed in this paper. The authors have used Finite Element Analysis using different simulation tools like Abaqus, Ansys, LS-Dyna and Autoform 3D that help to minimize the failure cost of materials and dies. This paper deals with those disparate approaches, discussing exhaustively the process and application of hydroforming, providing sufficient data to make readers identify the burgeoning areas of research.

This paper presents an attempt to develop an approach to predict the optimal process parameters for the Hole punching process on sheet metal. The Taguchi method is used to define the experimental procedure by its orthogonal array. The multiple responses of the Hole punching process, hole diameter and hole offset are optimised by the Grey Relational Analysis procedure. The statistical analysis of variance reveals the significant parameters which affect the process by analyzing the input parameters with the grey relational grade. The Non linear model obtained by this analysis is further processed by a Meta heuristic algorithm to obtain the optimality.

This paper presents a novel method to reduce the inrush currents produced by interconnecting induction generators. The method is based on the sequential energization of the contactors and a grounding resistor connected at the neutral point of a wye-connected stator. Analytical developments are presented, which permit to determine the optimum value of the neutral resistor directly. Theoretical and simulation analysis show that the proposed method can be almost as effective as the traditional three series resistor method. The proposed method requires only one resistor and one bypass contactor and is therefore more cost-effective than the traditional methods.

In the consolidation theory of sand drain foundation settlement, the influence of groundwater level changes on the soil consolidation has been paid less attention. Therefore, discussing those changes' influence will help to deepen and perfect the sand drain consolidation theory. Through theoretical research and field measurements, the concrete influences of water level weight, dissipation rate and other factors on the consolidation process are obtained. This helps to improve the consolidation theory and efficiency.

A hierarchically porous zeolite ZSM-5 is prepared under hydrothermal conditions by using hexadecyltrimethoxysilane as inhibitor and template. The physical and acid properties of the hierarchically porous ZSM-5 are characterized by XRD, SEM, N2 physisorption and NH3-TPD techniques. Benzene alkylation with methanol is carried out with both conventional and hierarchically porous ZSM-5 in a fixed bed reactor. The creation of mesoporosity in zeolite ZSM-5 promotes benzene conversion and xylene selectivity with respect to conventional counterpart.

As an international general finite element analysis software, ABAQUS has super nonlinear analysis function and is playing an increasingly important role in the numerical calculation analysis of geotechnical engineering structures. CAE module of its own provides a certain amount of convenience for the beginners, but it is inadequate in the face of more complex geotechnical engineering problems. Based on parametric language PYTHON, using its modular model code, bypassing the CAE module, the ABAQUS finite element analysis calculated and analyzed the influence of ER on the CFG pile composite foundation settlement and pile side friction. Finite element analysis and the results show that: the process of ABAQUS finite element analysis, which is based on the parameter language PYTHON, is simple and has very high computational efficiency and accuracy in the analysis complex geotechnical engineering problems.

Nimonic C-263 alloy is extensively used in the field of like aerospace, power generators and heat exchangers due to its higher thermal properties. In this work, an attempt has been made to investigate the effect of the cutting parameters (cutting speed, feed rate & depth of cut) on tool wear (flank wear) in the machining of this alloy with a PVD coated carbide insert. The experiments were conducted using Taguchi’s experimental design. A second order response surface model has been established between the cutting parameters and flank wear using response surface methodology. The predicted optimal value of flank wear for coated carbide is 0.190mm. The results are confirmed by conducting verification experiments.

A method for simultaneous determination of trace levels of Cd(II), Cu(II), Pb(II) and Zn(II) in food additives by inductively coupled plasma atomic emission spectrometry ( ICP–AES ) after soluble membrane filter pre-concentration was developed. Based on collection of the chelates of metal ions(II) with 2-(5-bromo-2-pyridylazo)-5- diethylaminophenol ( 5-Br-PADAP ) on soluble membrane filter, the analyte ions were pre-concentrated and separated from sample matrix solutions. Multi-channel membrane filter device and soluble mixed cellulose ester membrane were selected. Analytical parameters such as pH, amount of 5-Br-PADAP, sample volume, etc. were optimized. Under the matrix of Na+, K+ and Mg2+, the limits of detection were 0.02 – 0.03, 0.14 – 0.23, 0.31 – 0.53, 0.10 – 0.15 μg L-1 for Cd(II), Cu(II), Pb(II) and Zn(II) respectively. The developed method was successfully applied to sodium benzoate, potassium sorbate and basic magnesium carbonate with spiked recoveries of 94% – 115%. Some sample analysis results were checked by inductively coupled plasma mass spectrometry ( ICP–MS ) directly.

With the purpose to stimulate the technical development and to seek the new growth points in economy, governments of different countries attach great importance to the technical programming of the new generation, giving priority to the internet of things. It is also stated in the twelfth five-year-plan outline for national economic and social development of the People's Republic of China that the national infrastructure should develop with the safety of broadband blending to push the application of the internet of things.