Advanced Materials Research Vols. 143-144

Abstract: In this paper, NiTi-Ti2Ni-TiC composite powders were first prepared by in-situ reaction in molten salt and then sintered by a cubic high pressure apparatus under 8 GPa to produce bulk composite material at a short time. It was found that the composite was composed of TiC particles embedded in NiTi-Ti2Ni matrix, in which the Ti2Ni encapsulated TiC particles. The martensitic transformation of the NiTi matrix was evidenced by differential scanning calorimetry analysis. The research on the sintering mechanism shows that there may be a reaction like TiC +Ti2Ni 􀃆 Ti2C + NiTi existing under the pressure up to 8 GPa

Abstract: This paper is concerned with the exponential stability analysis problem for a class of neutral bidirectional associative memory (BAM) neural networks with parameter uncertainties and mixed time-delays where the parameter uncertainties are norm-bounded and the mixed time-delays involve discrete, distributed and neutral time-delays. By utilizing free-weighting matrix method and an appropriately constructed Lyapunov-Krasovskii Functional, some nove delay-dependent and decay-rate dependent exponential stability criteria are derived in the terms of linear matrix inequalities (LMIs). Meanwhile, the maximum allowable decay rate can be estimated based on the obtained results. Two numerical examples are presented to demonstrate the effectiveness of the proposed method.

Abstract: In order to explore key nodes natures and find out the core of weighted networks, the study advanced backbone network (BN) conception, developed largest eigenvalue algorithm of weight matrix (LEAWM) which utilized matrix characteristic spectrum to detect BN nodes, and done empirical research for two networks: (1) US air lines network, (2) stocks network of coal and power sectors in china stock market. The empirical results indicate that LEAWM is efficient for detecting the BN nodes with some important properties such as bigger degree and betweenness, BN is the core and backbone of its mother network.

Abstract: As one aspect of granular computing, hierarchical knowledge granularity can speed up solution, and reduce computational complexity. This paper describes the structure and hierarchy analysis of granularity simply, details the current methods of construction algorithms in granular computing, and emphasizes the performance comparisons of various construction algorithms, and finally reviews the applications of knowledge granularity in rule extraction, attribute reduction, cluster analysis, optimization theory, neural network and fuzzy control and so on.

Abstract: The traditional submarine voyage training has problems of high cost, long period and high risk. In this paper, a submarine voyage training simulation system was proposed based on virtual reality and submarine control theory. At first, the construction of the system and the functions of modules were described. The coach control system based on digital chart was realized, which can achieve functions of training environment and parameters setting. The model library of virtual ocean scene was built and then the scene was rended by Vega Prime. In order to remedy the deficiency of the network, a DR algorithm was explored, which can satisfy the realtime requirements of scene simulation and achieved the frame alignment between channels and coherence of observers.

Abstract: With the development of information technology, accounting attracts more and more peoples' attention. In this paper, we proposed the impact of network technology for accounting. This paper focuses on the design and implementation of some key techniques for accounting in the Internet. Simulation results are presented and have verified the validity of the proposed strategy

Abstract: Cement mortar shows piezoresistivity after being mixed with small amount of graphite, thus the resistivity of the material will changed with stress. In this study, specimens embedded double electrodes which made of cement based material with small amount of graphite (3 wt.% of cement) are used in the experiments of one-time loading and cyclic loading, and the relative resistivity are measured by a series connected AC circuit. The results show that the specimens’ piezoresistivity goes down while the stress increases, and different curves of piezoresistivity can be observed in experiments with different loading methods. The relative resistivities of the specimen show a similar change as strain.

Abstract: A wireless sensor network system is put forward that is applied in the field of monitoring wind load based on ZigBee technology. The hardware of the system adopts the SOC chip CC2530 as the core of the wireless communication model, and its front end CC2591 to extend the communication distance so as to reach the requirement of the specific application. In addition, the data acquisition model chooses pressure sensor monitoring wind load which connects to the microcontroller on the wireless communication model. The system software introduces sleep mode to realize the low power consumption when there’s no task in the system. The system is designed to monitor colossal buildings in typhoon situation, which will be applied to monitor the wind load on the cooling tower in power station soon.

Abstract: The precision of piezoresistive sensors is low between wide temperature range .The conditioning result isn’t ideal by analog approaches. Also the efficiency is very low. To improve this condition , a digital approach is introduced. It coverts sensors’ analog signal to digital value, and then uses polynomial and coefficients stored in singlechip to correct the digital value. At last , the singlechip coverts corrected digital value to analog signal to output. Its conditioning principle and calibration process is also described. We realized 4-to-20mA-current-loop-output of piezoresistive sensors using this aprroch. Calibration results show this method is efficient and low cost.

Abstract: A natural mordenite mineral has been used as a template to prepare a templated carbon. X-ray diffraction (XRD), nitrogen adsorption, scanning electric microscope (SEM) and cyclic voltammetry (CV) are used to analyze the phase composition, pore structure, micro morphology and electrochemical performance. The specific surface area of the templated carbon is 724m2/g, and the mesoporosity is high to 63.8%. In H2SO4 medium, the carbon has large capacity and good rate capability. The capacity of the carbon decreases from 103 to 94F/g (the capacity remains more than 92%) when the scan rate increases from 10 to 200mV/s. The CV curve of the templated carbon exhibits rectangle-like shape, and the shape keeps well at high scan rate.