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Yang C.,Wuhan University | Li Q.,Wuhan University | Li Q.,Shenzhen Key Laboratory of Spatial temporal Smart Sensing and Services | Liu J.,State Grid Corporation of China
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2013

From the engineering point of view, we propose a novel dual sink-based continuous disaster tracking (DCDT) algorithm, which consists of a static sink and a mobile sink guided by GIS. The two sinks can cooperatively work in an intelligent model in which the mobile sink can calculate the right position to collect the information from boundary nodes; in which the static one can reduce much message transmission as well as energy consumption based on centroid algorithm. The simulation result shows that our solution can distinctly prolong the network life time than single sink network in continuous object tracking.


Tu W.,Wuhan University | Li Q.,Wuhan University | Li Q.,Shenzhen Key Laboratory of Spatial temporal Smart Sensing and Services | Fang Z.,Wuhan University
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2013

A heuristic algorithm integrating simulated annealing and Voronoi long edge guided optimization is proposed for large scale vehicle routing problem. The simulated annealing strategy is employed to accept some bad neighborhood solutions in local search. Voronoi long edge guides to improve the unreasonable local structure in routes. A large scale vehicle routing benchmark instances is designed to test the proposed algorithm. The results show that the proposed algorithm can provide high quality solution in a short time.


Sun X.,Wuhan University | Yang B.,Wuhan University | Li Q.,Wuhan University | Li Q.,Shenzhen Key Laboratory of Spatial temporal Smart Sensing and Services | Jiang S.,Wuhan University
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2013

We propose a linear geometric coding method for efficient transmission of complicated 3D building models. Firstly, the building model is converted into volumetric representation, and the octree index of the original model is established. Then the geometric information of the building model is linearly encoded and compressed according to the expansion patterns of the spatial index structure between levels and their empirical probabilities. Finally, the spatial density field is constructed, and the linear data stream is decompressed and reconstructed based on the improved MC algorithm. Experimental results show that the proposed method is not constrained by the topology of the original models' surfaces, and it could greatly reduce the data volume and the response time in network transmission of complicated 3D building models with preservation of visual quality.


Chen L.,Wuhan University | Pan Z.,Wuhan University | Mao Q.,Wuhan University | Li Q.,Wuhan University | Li Q.,Shenzhen Key Laboratory of Spatial temporal Smart Sensing and Services
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2013

This paper presents a novel approach of detecting forbidden traffic signs. In this approach, a HOG-LBP (histograms of oriented gradients-local binary patterns) adaptable fused feature is proposed. The traffic sign image is cut into several non-overlapping blocks, in each block, the HOG and LBP features are weighted serial fused based on each block's gradient value. Then to get classifier which is used in detecting forbidden traffic signs, SVM (support vector machine) is used in training features. The experimental results show that proposed fusion feature is more effective and feasible than HOG, LBP and simple serial fused HOG-LBP feature.


Zhou B.,Wuhan University | Mao Q.,Wuhan University | Li Q.,Wuhan University | Li Q.,Shenzhen Key Laboratory of Spatial temporal Smart Sensing and Services | Tan W.,Wuhan University
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2013

Link dynamics of vehicular ad hoc networks (VANETs) have great difference with that of the traditional mobile ad hoc networks (MANETs) due to the impact of simulation scenarios. Based on Manhattan mobility model, the influence factors of vehicular nodes in urban environments are analyzed, including traffic light and drivers' behavior. Analytical expression of expected link lifetime is derived. The impact of traffic light and drivers' behavior to the expected link lifetime is analyzed. The simulation results verified the accuracy of the analytical results.

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