In formal language theory of two-dimensions, 2D picture grammars are powerful tools to generate picture languages. In this work, we incorporate the idea of membrane systems (also called P systems) into 2D picture gram...
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In this paper, the problems of exponential stability and -gain analysis of event-triggered networked control systems (NCSs) with network-induced delays are studied. We first propose event-triggering conditions in the ...
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Chemical exchange saturation transfer (CEST) is a new mechanism of contrast generation in magnetic resonance imaging (MRI) which differentiates molecule biomarkers via chemical shift. CEST MRI contrast mechanism is co...
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ISBN:
(纸本)9781467311496
Chemical exchange saturation transfer (CEST) is a new mechanism of contrast generation in magnetic resonance imaging (MRI) which differentiates molecule biomarkers via chemical shift. CEST MRI contrast mechanism is complex and depends on radio frequency (RF) pulses used in experimental conditions. To find the optimal RF pulse, numerical solutions of Bloch-McConnell equations may be used. The purpose of this work is to compare the effects of different RF pulses on the CEST phenomenon. First, a two-pool exchange model for CEST in MRI is used. Z-spectra and signal calculations for the two-pool model have been carried out for some RF pulses. Efficiency of both continuous and binomial RF pulses is investigated by calculating three parameters, namely: CEST image contrast, flip angle and specific absorption ratio (SAR). The contrast of CEST image is considered proportional to amount of saturation. As a binomial RF pulse, WALTZ-16* demonstrates a good efficiency, but generates some unwanted direct saturations. On the other hand, continuous RF pulses do not create any unwanted direct saturation, but have less efficiency.
So far, all of the approximate Jacobian controllers for robot manipulators proposed in the literatures have assumed that the exact joint velocity measurements are available. In this paper, we propose alternative contr...
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A method based on multi-agents and ANN (Artificial Neural Network) was proposed to solve the pursuit-evasion task in continuous time-varying environment. According to this method, several autonomous agents with 8 circ...
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In this paper, a modified method for landslide prediction is presented. This method is based on the back propagation neural network(BPNN), and we use the combination of genetic algorithm and simulated annealing algori...
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Feature extraction in brain-computer interface (BCI) work is an important task that significantly affects the success of brain signal classification. In this paper, a feature extraction method of electroencephalograph...
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With more and more attention on the grid current harmonic in recent years, many control schemes of the Pulse Width Modulation Voltage Source Converter (PWMVSC) have been investigated. Conventional PI controller has sh...
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In Ultrasound imaging, speckle noise is the most serious problem which affects the performance of images. Non-local mean filter is a nice method to remove the speckle noise, but the algorithm' computational comple...
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The intersecting cortical model(ICM) is driven from the pulse-coupled neural networks (PCNN), and a lot of works have been done on it. In this paper, we have proposed a method, which is modified from the PCNN, to retr...
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