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Chaos in a fractional-order neuron network system with varying time delays is illustrated. Chaotic synchronization system for such system is constructed. The theoretic analyses are given by Laplace transformation theory, the bifurcation graph with respect to coupled parameter is presented, and the numerical experiments are presented. The study shows that the chaos in such fractional-order neuron networks...
Broadband ultrasound attenuation (BUA) is a useful predictor of the mechanical properties of cancellous bone. It is obtained by ultrasound pulse wave through-transmission measurements into the bone. Due to the strong attenuation in the bone, the received signal is weak and intervened with noise, which confines the measured depth and brings estimation errors. An effective solution to this is the coded...
This paper presented a nonlinear voltage modeling procedure of a proton exchange membrane fuel cell (PEMFC) stack by neural networks based on particle swarm optimization (PSO). PEMFC stack is a complex nonlinear system which is hard to model by traditional ways. So neural networks based on particle swarm optimization (PSONN) was developed to identify a nonlinear PEMFC stack voltage model. In the paper,...
The Application level multicast is an important technique for indirect communication model. However, there are few works to integrate them together. An Infrastructure for Application Level Multicast Routing in Publish/Subscribe system (IALMRS) is proposed in this paper. We realize a multicast routing protocol for such Publish/Subscribe systems based on IALMRS. From the tests for this multicast routing...
GridFTP is a secure and efficient data transfer protocol in Grid. This paper proposes a test scenario for the GridFTP traffic features. Firstly it gives a general description of the testbed traffic from the aspects of packet characteristics and throughput distribution; then analyses the self-similarity features of the GridFTP traffic and their decomposed data flows both in WAN and in LAN. Analysis...
The rotating machinery for engineering process and materials science has become faster and lightweight recently. The machinery has been required to run for longer periods of time and reliable operations. Because machine breakdowns and consequent down times severely affect the productivity of factories or the safety of products and process success depends on the reliability and the efficiency of related...
The current research of auto ID (automated identification) boosts the ubiquitous applications in a broad spectrum including manufacturing and supply chain. This paper proposes an information sharing system framework dwelling on the smooth and integral information access of manufacturing information (e.g. product information, design information and sales information etc.), and the whole product lifecycle...
This paper discusses the basic features and the models of spatial data. Beyond current topology and distance relations, it comes up with the location, neighborhood, nearness and influence conceptions of spatial data and consummates the descriptions of spatial relations. It points out only the location data is the primitive data, other spatial relations are derived data. Based on the computability...
Localization is one of the imperative issues in wireless sensor networks. The classical range-free and range-based localization algorithms have respective pros and cons, which cannot gracefully meet the practical requirements, such as the heterogeneity of network and irregular distribution. Thus, the high-accuracy localization algorithm HILS (hybrid iterative least square) is proposed in this paper,...
The high frame rate (HFR) ultrasonic imaging system based on linear frequency-modulated (LFM) signal constructs images at a high frame rate and the signal-to-noise rate (SNR) of this system can also be improved. Unfortunately, such pulse compression methods that increase the SNR usually cause range sidelobe artifacts. In an imaging situation, the effects of the sidelobes extending on either side of...
In traditional synthetic aperture ultrasound imaging system, the elements in a transducer array transmit ultrasound pulse consecutively and then all elements receive the echo signals simultaneously. Though it is capable of obtain an complete dataset of the echoes, the process is very slow and thus not practical due to too many transmission times. We developed an simultaneously transmitting approach...
Manufacturing information (MI) plays an essential role in modern digital manufacturing technologies, and it includes all the information referring to the manufacturing activities. The traditional MI sharing models cannot be used in an extensible and flexible application, and also dwell little on the performance issues in MI sharing. In this paper, we begin with analyzing the differences between MI...
The cluster-based communication protocol in wireless sensor networks can decrease the energy consumption effectively. Since the reliability of the sensing task is seldom analyzed and the data-centric sensing task focuses more on the data reliability, the RBD (reliability block diagram) is used to model the data reliability of wireless sensor networks. Then the malfunctioning node is defined and researched...
The energy conservation is the intrinsic issue of the wireless sensor network (WSN). The lack of energy of some necessary sensor nodes will affect the accurate data aggregation as well as the effective lifetime of the network. In this paper, the problem of predicting which energy level the WSNs or nodes stay in is addressed. Since the primitive method that exchanges messages through nodes could not...
A new nondata-aided frequency offset estimation method has been proposed for GMSK which is based on Viterbi algorithm to remove the information phase of the complex envelope signal. It has wide frequency offset estimation range, and its feedforward structure made itself simple digital implementation. Its complexity would be controlled by the Viterbi algorithm parameter. Simulation results have shown...
Spiral k-space scanning is a rapid magnetic resonance imaging (MRI) technique that can provide an order of magnitude reduction in scan time compared to conventional spin warp techniques. Parallel imaging is another method for reducing scan time that exploits spatially varying radiofrequency (RF) coil sensitivities to reduce the amount of data required to reconstruct an image. Combining spiral scanning...
Spiral k-space scanning is a rapid magnetic resonance imaging (MRI) technique that can provide an order of magnitude reduction in scan time compared to conventional spin warp techniques. Parallel imaging is another method for reducing scan time that exploits spatially varying radiofrequency (RF) coil sensitivities to reduce the amount of data required to reconstruct an image. Combining spiral scanning...
The high frame rate (HFR) ultrasonic imaging system, which is developed with limited diffraction beams, constructs images at a high frame rate. Because of one transmission for constructing image, the system suffers from lower signal-to-noise rate (SNR). The proposed method uses linear frequency-modulated signal (or chirp) as excited signal. For the higher time-bandwidth (TB) products available in...
A kind of high frame rate (HFR) 2D and 3D imaging method was developed in 1997. Because only one transmission is required to construct an image, this method can reach an ultra high frame rate (about 3750 volumes or frames per second for biological soft tissues at a depth of 200 mm). Compared with conventional delay-and-sum (dynamic focusing) method, the new method uses the fast Fourier transform (FFT)...
On the basis of two Liaoning Province remote sensing-based soil erosion survey and national water resources investigation and assessment, the change process for land use and cover has been analyzed by adopting landscape ecology method under the support of remote sensing and GIS in the middle and lower reaches of Liao River Basin. GIS spatial processing method and hydrological method are adopted to...
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