In the two-tiered wireless sensor networks(WSN), how to design a more efficient distributed cluster head election algorithm is a crucial problem. In all algorithms proposed before, some depend on random greatly, and others only take homogeneous into account. On the basis of them, this paper proposes a new practical approach, in which the old cluster head, as to the power information, chooses the two nodes which supply the cluster with the maximum lifetime if they are elected as the new cluster head and the new one’s assistant. The simulation performance results demonstrate the efficiency of the method compared with the random choosing algorithm in much longer network lifetime.
In view of existing stealth-scanning detection technology insufficiency, providing a new model based on characteristic of network’s traffic for detecting stealth-scan, it adopts a different way from most existing detection techniques. It not only checks packet individually, but also combines the way based on conversation, and removes various kinds of “noise” activity of scanning that interference detection to go. Primary experiment indicates that this detection model has higher rate of accuracy and lower rate of false negatives to various stealth-scan.
This paper combines the SST algorithm with SEA algorithm, and substitutes λ-modular polynomial for modular polynomial in the SST algorithm. It proposes an algorithm to generate Legendre form elliptic curves based on lift. The algorithm not only improves the speed of generation of the elliptic curve, but also enhances the efficiency of the curve selection.
The mechanism for multi-dimensional cloud model is studied. The formal representation of a clouds model for transform action between qualitative and quantitative knowledge is presented. This kind of representation reflects fuzziness and randomness contained in linguistic concepts, and can interpret uncertain reasoning process rationally when several qualitative rules are activated simultaneously. Using the data sets of KDD99, the experiment result shows that this approach can detect unknown intrusions efficiently in the real network connections.
As a precondition of the computer aided design(CAD), the engineering drawing vectorization has high research value and broad applications. This paper discusses the engineering drawing vectorization methods. Based on the study and analysis of the existing problems in vectorization, the future research direction is introduced. There are certain practical signification for avoiding, reducing vectorization errors and improving the vectorization quality of the complicated engineering drawings.
An automatic video object segmentation algorithm based on wavelet transform and moving edge detection is proposed. Firstly, the new method makes the two-dimensional wavelet transform for two successive frames. Then change detection method and Canny edge detection are applied in wavelet domain. After merging the different edge masks with the union operation, the robust difference edge map of the inter-frame difference image can be obtained. Combining with the current frame edge map, background edge map and previous frame’s moving edge, the current frame’s moving edge can be calculated to extract video object. The algorithm is robust to the entire motion and local deformation of object. The experiment results show that the proposed algorithm is fast, simple and accurate.
This article gives analysis on independent component analysis (ICA) based on the recognition of facial expression. It trys to find the influence of single IC to the recognition rate of facial expression. Then the article concludes the way of how to select independent subspace efficiently.
On the foundation of studying former connecting area algorithms, the paper presents a pixel labeled algorithm based on recursive method of connecting area in binary images. The algorithm determines the distribution and count of connecting areas through once scanning of image. It mainly includes two steps in the algorithm. Firstly, scanning the input binary image is used to get the whole connecting labeled area and the equal marks list. The second step is to analyze the equal marks list by recursive method to ascertain the right distribution and count of connecting areas. Experiments show that it can exactly detect any connecting areas in binary images, which contains complicated shapes and random number (less than 1 000).
It is significant and being unsolved yet for building a fuzzy Petri net to determine all parameters of fuzzy production rules. Genetic algorithm combined with BP algorithm is originally introduced into the procedure of exploring parameters of FPN. An exploring strategy based on double-stage optimization is proposed. Realization of this strategy don’t depend on experiential data and requirements for primary input are not critical. Simulated experiment shows that the trained parameters gained from above strategy are highly accurate and the resultant FPN model owns strong generalmzing capability and self-adjustmeion purpose.
This paper proposes a novel and simple method of gait feature extraction. Body silhouette extraction is achieved by background subtraction. The body silhouette is projected along its midline to obtain the fore-and-aft midline projection vectors, which are then combined into one dimensional data vector as the gait feature. PCA is applied to reduce data dimension, and gait classification and recognition is performed by support vector machine. The result of the experiment demonstrates that the approach is effective and has encouraging recognition performance.
To the problem such as low efficiency, highly consumed that appears during video transmission in teleoperation system, this research uses sequence number, slide windows, retransmission, acknowledgement and congestion control technique which include RUDP protocol for the video transmission in teleoperation system. The research indicates that RUDP is more efficient on transmission than TCP or UDP.
Traditional methods on 3D-restruction are not fit to rotary slice, a feasible method based on B-spline interpolation is posed, aimed at 3D-restruction on rotary slice. It can not only solve the problems on 3D modeling but also remarkably improve the quality compared with using triangular faces while drawing the curve because of using the NURBS interface programming in OpenGL. In addition, the method is also suited to parallel slice.
The paper analyzes the problems of image transmission in the HIFU tele-medicine system, and puts forward a method to cut a trapezoid area from the ultrasound image. It is based on C/S network model to implement no interval image transmission by Winsock programming that helps to control and judge the transmission status. The thesis employs multi-thread method to make good use of system resources, speed up communication velocity, reduce the coupling degree and meet the needs of image transmission in tele-medicine application.
This paper discusses the construction of workflow design platform in E-government system. It can customize detailed workflows via graphics and implement dynamic workflow based on workflow engine. It monitors process of workflow and dynamically adopts it, so insuring customized workflow to execute effectively.
As embedded data acquisition system is evolved continuously, data is stored in storage in term of a usual file system´s format more and more. Aimed at the characteristics of embedded system itself and the problem with cache mechanism, it is very necessary for data storage system to adopt some kinds of recovery mechanism to settle system fault. This paper presents a kind of recovery mechanism based on specialities of embedded data acquisition system, and analyzes and realizes it.
This article designs and implements a high available application development platform, which provides a flexible programming environment. It not only includes a high available application development framework, but also includes the checkpoint service, distributed lock service, event service, message service and membership service which are indispensable for high available application. Based on this platform, developer can concentrate on the application’s business feature, not the high availability.