Author Topic (AT) model is widely used to find the author's interests in scientific literature, but AT model cannot take advantage of the correlation between category labels and topics. Through integrating the inherent category labels of documents into AT model, Labeled Author Topic (LAT) model was proposed. LAT model realized the predicate of multi-labels by optimizing the mapping relation between labels and topics and improved the clustering results. The experimental results suggest that, compared with Latent Dirichlet Allocation (LDA) model and AT model, LAT model can improve the decision accuracy of multi-labels, and optimize the generalization ability and operating efficiency.
Train tracking problem under moving block condition was studied according to the characteristics of CTCS-4 train operation. A Multi-Agent System (MAS) model of multi-train tracking under moving block condition was built based on multi-Agent theory and the interaction mechanism between the train and the Radio Block Center (RBC) was proposed. The model realized the real-time vehicle ground communication and safe distance control of multi-train tracking. The influences of the speed change in train tracking process and different line initialization density on line traffic were simulated, and corresponding quantitative analysis conclusions were obtained. The simulation results show that the proposed MAS model can realize Complex System (CS) formal description of the train control system in the static and dynamic environment, and accurately describe CTCS-4 train tracking mechanism. The example evaluation results prove the feasibility and effectiveness of the proposed method.
To effectively capture the dynamic information of the gait and accelerate the authentication and identification, a novel gait recognition algorithm was presented in this paper, which employed the row mass vector of the Frame Difference Energy Image (FDEI) as the gait features. The gait contour images were extracted through the object detection, binarization, morphological process and connectivity analysis of the original images. Using the width of the contour images sequence, the quasi-periodicity analysis and the row mass vector of the frame difference image were obtained, then the Continuous Hidden Markov Model (CHMM) was employed to train and recognize the parameters of model. The proposed algorithm was applied to Central Asia Student International Academic (CASIA) gait database. The experimental results show that it can easily extract the features of the gait with low dimension, achieving fast recognition speed and high recognition rate, so it can be used for real-time gait recognition.
To evaluate the operational efficiency and emergency strategies of the trail transit under different passenger flow conditions, also simulate and analyze the emergency strategies quantitatively, a simulation platform for urban rail transit was proposed. This system modeled four main objects that consisted of the kinetic model of train, the Automatic Train Control (ATC), the trackside equipment and the moving block system. On this basis, the whole simulation system was designed and implemented based on VC〖KG-*3〗+〖KG-*3〗+ development platform combined with computer network and database technology. Finally, the operation of the train was able to be automatically implemented on this simulation platform driven by the train timetable. The system was assessed by using the data of the rail transit of Shanghai 8th line and the simulation results show good consistency with the real timetable.
With the rapid development of Chinese railway, requirements for running safety of trains are more high. This paper used the Event-B formal modeling approach to research on the high-speed train safety distance control. With the support of simulation tool Rodin, combined with the multi-Agent theory, the safety distance control model of multi-train operation was constructed. The simulation researched the modeling and verification on the minimum interval tracking control for high speed train. The simulation results show that, the binding of formal verification methods of Event-B and Multi-Agent System (MAS) is meaningful. So the method has some practical significance for the modeling and verification of complex system.
Since the isotropic diffusion will easily blur edge features,and coherence-enhancing diffusion will produce pseudo striations in the background regions during the denoising process, a weighted diffusion algorithm was proposed to reduce the Rician noise of Magnetic Resonance Imaging (MRI) image according to the distribution of noise. A threshold value was calculated by the Rician noise variance in the background region of MRI image, which might be used to distinguish the image background and the edge of Region-Of-Interest (ROI). A weighting function combining the isotropic diffusion and the coherence-enhancing diffusion based on the calculated value was constructed. The constructed function could adaptively adjust the weight values of two kinds of diffusion in different structural regions in order to give full play to the advantages while overcoming the disadvantages of the above two kinds of diffusion.The experimental results show that it is better than some classical diffusion algorithms in Peak Signal-to-Noise Ratio (PSNR) and Mean Structural Similarity(MSSIM).Thus, it has better performance on noise reduction and edge preservation or enhancement.
Aimed at image watermark robustness, an evaluative method based on synergetic order parameter and its usage was first advanced. Many kinds of robust experiment of Image carrier were done. After procession, the synergetic original order parameter of patterns in the set were calculated and compared. Through validation by the order parameter evolvement curves, their robust conclusions were gotten. This method is more convenient and applied than the correlative coefficient method, although the two methods have same conclusion.
Personal Digital Assistants and Personal Computers often utilize synchronization protocols in order to maintain data consistency. These protocols operate in environments where network resources such as bandwidth, memory, and processing power are limited. In this paper a novel PDA synchronization scheme(CPISync) predicated upon recent information-theoretic research was introduced. The characteristic of this scheme was that its communication complexity depended on the number of differences between the PDA and PC. Moreover, experiments showed that the computational complexity and energy consumption of CPISync were practical and that the overall latency was typically much smaller, which played an important role in their scalability. Thus, CPISync had a potential of significantly improving synchronization efficiency for PDAs on large, heterogeneous, wireless networks.