Advanced Materials Research Vols. 1044-1045

Abstract: This paper presents a new distributed index tree named RDB⁺-Tree and a concurrency control algorithm named VTC-RDB⁺. In RDB⁺-Tree, the leaf node is organized for a hash list. The principle of VTC-RDB⁺ algorithm can be established by utilizing multiple elements which are in favor of concurrency control and by combining with version and time control method. Theoretical analysis and experimental results show that the RDB⁺-Tree index tree and VTC-RDB⁺ algorithm can effectively enhance the query and updating performance of the massive data in the distributed circumstance.

Abstract: High squint millimeter wave SAR can be applied in missile-borne imaging seeker, but it’s very sensitive to the motion errors. Both the high squint SAR imaging algorithm and the motion errors compensation method are very important for achieving well focused SAR image. Therefore, a motion compensation method integrated with the imaging algorithm is proposed. Firstly, the expression of instantaneous squint range is given according to the imaging geometry model of high squint SAR. Then, the components of motion errors are separated and estimated, using the parameters of inertia navigation system (INS). Finally, the envelope and phase corrections are performed in high squint SAR data through the obtained motion errors. The effectiveness of the proposed approach can be verified by the imaging results of measured millimeter high squint SAR data.

Abstract: An image-adaptive watermarking algorithm based on wavelet transform was proposed. At first, A digital image used as watermarking was scrambled. Next, the original image was decomposed by discrete wavelet transform,and in accordance with the characteristics of human visual system, wavelet decomposition in the low-frequency domain, Methods which average of adjacent domain instead of single wavelet decomposition coefficients was used to estimate and quantitative, watermarking was adaptively embedded in wavelet coefficients of low-frequency domain. At last, the simulation experimental results show that the algorithm for a variety of conventional image processing has good robustness.

Abstract: The article analyzed the shortage of P_schema, and brought forward an improved method P_schema++,.Nesting structure.multi_citing element, alternative element was picked up to format a new type, and then to a relation table. P_Schema++ provided a method for storage of Complex XML document in RDB.

Abstract: This paper puts forward a creative idea that the tiled map editors can be used to replace specialized editors in the development process of crossword games, and this has been verified in a complex Chinese crossword game project. The final results prove the idea completely feasible. This indicates the development process of casual games can be greatly accelerated with appropriate tools and targeted data structure design.

Abstract: In Optimized Link State Routing Protocol, the choice of Multi-Point Relays is based on connectivity. Based on the connection time, this paper chooses MPR by taking reference in the degree of congestion of link layer of nodes while making a balanced processing of network load. The experimental results have shown that the improved MSLBOLSR(Multidimensional Sense and Load Balanced OLSR) protocol has advanced visibly in terms of the leisure degree of application layer and the time-delay, etc.

Abstract: In this paper, a novel model, HDP-HMM-SCFG is proposed for representing and classifying activities based on motion trajectories. In the model, activities are represented by stochastic grammar using trajectory, where trajectory segments are considered as observations emitted by the grammar terminals attached with HMMs. Then, by replacing the Euclidian distance in the kernel function of Gaussian radial radix with EMD-DTW, which is proposed to measure the distance between two trajectories by integrating the pros. of both EMD and DTW, multi-class SVM classifier is constructed. Experiments on ASL dataset are carried on to validate our approach.

Abstract: With the application of space syntax theory in urban planning and architecture designing is growing continuously, the number of the urban spatial configuration models based on space syntax will be more and more. However, the use of these models still lacks of some intelligent retrieval models currently. This paper splits the urban spatial configuration into regular grid structure, and uses visibility segmentation to construct the relationship diagrams and then extracts space syntax variables from each node to form the four-dimensional histogram. Furthermore, this method calculates the similarity among models through the measurement of the histogram distance, thus realizes the retrieval of the urban spatial configuration. Experimental results show that this model has a satisfactory retrieval results.

Abstract: This paper focuses on the method of pseudo-code ranging based on time divided CDMA-OFDM mixed signal system. A snapshot-replay method is proposed to make the receiver provide the measurement result of pseudo-code ranging under frequency fading channel, which enhance the continuity of the output of pseudo-code ranging result. The problem of ranging through tracking loop under frequency fading channel is analyzed. This paper analyzed and studied the design and realization of snapshot-replay method of pseudo-code ranging. Further, the impact due to limited frequency band is analyzed. Through software simulation and hardware verification, this method of snapshot-replay pseudo-code ranging is proved to be effective to enhance the continuity of the output of pseudo-code ranging result.

Abstract: The main objective of time series analysis is to develop models that can establish the relation between variables,the paper ,An improved method of the RBF is proposed,which is a five-layered network structure comprising of an input layer,wavelet layer, product layer, output layer and polynomial regressive weight layer.which uses an online optimization approach, the method uses an offline learning method known as SNPOM,the polynomial weights are updated many times during the process of looking for the search direction to update the nonlinear parameters. The experiment showed that the optimization technique can speed up the convergence rate of nonlinear model during the learning process.