The genetic algorithm is the intelligence computational method widely used in solving the optimization problems, however many current genetic algorithms has premature convergence and stagnation behavior while solving complex question. This may because the algorithm had lost the ability of discovering that new or potential genetic material before convergence limited its search to solution space with wide range. Enlightened by hierarchical fair competition widely existed in nature, this paper has studied a model based on Pyramid model of hierarchical fair competition which uses pipeline structure divided sub-population rank according to fitness gradient, guarantee the recent discovery potential genetic material to obtain full development by maintaining a certain global selection pressure under reducing the local selection pressure of sub-population. Unlike traditional genetic algorithm's strategy which attempts to jumps out local optima region from high evolutional population included a high similarity "building block", the Pyramid model continuously maintain the sub-population with the medium fitness value to ensure keeping the multiplicity of the population by the strategy which the new local optima is bottom-up bred and processed unceasingly. Finally, this paper confirms the validity of the algorithm and the multiplicity of the population by HIFF128/256 problems based on binary encoding, and compared the improved algorithm from the solution quality and standard deviation of the population with traditional genetic algorithm, proves this improved algorithm can effectively alleviate premature convergence problem of the traditional genetic algorithm.
The process of retrieving desired or similar images from a large collection of images on the basis of features is referred as Content Based Image Retrieval (CBIR). In this paper, a integrated CBIR system is proposed using combined features and weighted similarity. The features include visual features of color, texture and shape and key text metadata. Some experimental simulations have been presented to show the accuracy and efficiency of the proposed retrieval method.
In order to improve the solution accuracy and the convergence of Population Migration Algorithm (PMA) and avoiding its prematurity, in this paper, we combined chaos theory with PMA. By introducing logistic mapping of chaos theory into PMA, we use the ergodicity, randomicity and regularity of chaos theory to attain an improved algorithm. The experimental results show that: by introducing the ergodicity, randomicity and regularity of chaos theory into PMA, the solution accuracy and the convergence property of PMA can effectively improve and effectively avoid prematurity phenomenon. The improved algorithm performs very well.
Seismic data is generated by a sharp pulse, which transforms into to Earth and is reflected by the layer status in the Earth. The Data is 3D or 2D. Because of transforming through the Earth, Seismic data has wide main lobe and strong side lobe, which is different from that of the sharp pulse. In order to recover the character that is similar to that of sharp pulse, the 2D and 3D seismic data is usually processed by the deconvolution. The data includes down going data and up going data mainly. The deconvolution is done by down going data in the general procedure. In this paper, it is done by up going data statistical distinctively. The new methods can get stable deconvolution operator and deconvolution result. It can be used to process the data that is contaminated high-frequency noise. The new approach can get well data to be used in the following process flow and bring a better result to interpretation and application.
The overall objective of this program is to build an effective and practical and efficient campus network. First, it clarifys the needs of the existing campus network, such as online office, school finance, e-mail and other related network information services. Then it provides a method to meet current, namely the use of Gigabit Ethernet. Finally, the network indicates a greater in the future state solution: using Gigabit network.
Researching on cavitation of propeller which is an important part of ship bubble wake has important signification for studying ship bubble wake. The three viscous flow field of a five-blade high-skew propeller was simulated with numerical method. Based on RANS method, SST turbulent model and Single full cavitation model were used to simulate and analyze the cavitation characteristics of the propeller in open water condition and behind ship wake, and the influence of wake on the propeller's characteristics. The results showed that the method and numerical model were feasible for the good accordance between numerical results and test data. At the same advanced velocity, the coefficients of torque and thrust in wake were all bigger than those in open water, and at the same cavitation number, the area of cavitation on propeller in wake was broader than that in open water.
This article focuses on the comparison between China and U.S in middle school mathematics teaching choreography, we want to find the different in the attention to the application problem and treatment. And we also focus on the application of U.S. high school mathematics textbooks scheduling problems, choosing a representative sample mathematical textbooks course1-3 published by PRENTICE HALL for research. And we use examples to show that the materials have the three levels of colorful mathematical application problem. Then we can know the rich life reality and knowledge background in American middle school students' mathematics study and experience the real challenges of U.S. high school students faced in math test. Expect to bring readers a wealth of educational resources.
Secure localization in wireless sensor networks (WSNs) has received a great deal of attention with the increasing applications of wireless sensors. Security issues of localization in WSNs need to take into account attacks from both external and internal nodes. In this paper, we propose a secure localization scheme based on trust evaluation called trust based secure localization (TBSL) to evaluate the trust of beacon nodes through detecting the identity and the behavior of such node and using the credible position information for localization in WSNs. Simulation results show that our proposed scheme can improve the accuracy of localization in a hostile environment.
This paper designs and implements a C-like language interpreter using C++ based on the idea of modularity. The whole system can be divided into three modules, namely, lexical analyzer, syntactic analyzer and evaluation of expression. During the design, token is being used. The design puts great emphasis towards code reusability and extensibility, which makes it easy to embed the code into other C++ programs. The final testing result shows that the implemented interpreter realizes almost all the interpretation functions of C-like language, including the interpretation of interface function call. It can also be used as script engine of games to control game logic through text, and games can be modified during running without recompiling the source code. Moreover, it has good portability. It can successfully run on different operating systems like Windows XP, MAC OS X 10.6.1, and iPhone OS 3.0.
While modern anti-counterfeiting printing technologies usually adopt special ink, laser holographic images, line texture, they need to increase certain supporting printing equipment and the cost. They have such shortcomings as high cost, complex technology, narrow application area and no information hiding, etc. This paper aiming at these problems proposes a kind of information hiding technology based on the shapes of halftone-AM-dot(Amplitude Modulation). The technology combining modern communication modulation technology and information coding technology, chooses anti-counterfeiting information as modulation signal to modulate dot shapes and makes itself carry information in AM screening image process. After plenty of experimental simulation, this method realized the information hiding. It can be used to anti-counterfeiting printing with low cost and excellent performance.
Mobile ad hoc network especially follows multihopping mechanism for routing to make a path from source to destination. If we have a sound and solid routing path that would be efficient, reliable and adaptable to the different scenarios of network too by following the next hop mechanism and also should be the farthest node with in the cluster then we could achieve better performance by the network. This paper gives more emphasis on the same phenomenon by simulating the protocol EPSAR over ADOV (reactive) and DSDV (proactive) existing protocol and also elaborates the mobility issue. This paper also presents the couple of simulations of EPSAR over multiple network (i.e. grows in terms of number of node) and also examines the performance and the feasibility of EPSAR by considering the different network parameters i.e. Data Packet sent, Delivery Ratio and End-to-End Delay.
Direct Anonymous Attestation (DAA) is an anonymous protocol designed for TPM/TCM or other embedding devices. Recently, DAA schemes based on the pairing continues to advance rapidly, but it has a certain problems to put the scheme into application. This paper focuses on the practicability and feasibility for the design of the pairing DAA protocol and system. Our first contribution in this paper is presenting a pairing less DAA scheme for TCM, only 2 pairings required in the whole protocol, Furthermore no pairing computation required inside TCM. The second contribution is to design and implement a test platform prototype for analyzing and evaluating the pairing DAA scheme. We analyze the influence factors like elliptic curve selection, preprocessing and so on. The experiment results show that the trade-off between the security strength and the performance must be taken into the comprehensive consideration for pairing DAA design.
With my school of Information and Computer Science "Cryptography" course teaching practice, this mainly from the theoretical teaching, laboratory teaching two aspects of cryptography in some of the feasibility of teaching methods are discussed, and teaching content design. Teaching practice in recent years show that the method can receive better teaching results. Since 2004 our school opened, "Cryptography" course, in practice, found that each year thesis topics of time, there were many students choose the topics and cryptography-related topics as a graduation project, and can pass defense, which can also prove that the teaching methods discussed in this article can receive good results.
This paper introduces the study result of technique of NDIS driver development in Windows operating system, and designs a system based on NDIS to catch and classify the network packets. To improve the efficiency of packet classification and filter, the idea of Hash function is propose to classify and filter the packets.
Nowadays, local features are widely used for content-based image retrieval. Effective feature selection is very important for the improvement of retrieval performance. Among various local feature extraction methods, Scale Invariant Feature Transform (SIFT) has been proven to be the most robust local invariant feature descriptor. However, the algorithm often generates hundreds of thousands of features per image, which has seriously affected the application of SIFT in content-based image retrieval. Therefore, this paper addresses this problem and proposes a novel method to select salient and distinctive local features using integrated visual saliency analysis. Based on our method, all of the SIFT features in an image are ranked with their integrated visual saliency, and only the most distinctive features will be reserved. The experiments demonstrate that the integrated visual saliency analysis based feature selection algorithm provides significant benefits both in retrieval accuracy and speed.
The popularity of modern information technology makes it urgent to construct a new English teaching model based on the integration of technology and teaching. Such integration targets at improving the traditional teaching mode, representing a trend in the curriculum reform home and abroad. This paper aims at information technology and college English teaching integration, analyzing the importance and efficient measures for the implementation and spread of new and efficient teaching model and methods.
Multiple objects tracking is a challenging task. This article presents an algorithm which can detect and track multiple objects, and update target model automatically. The contributions of this paper as follow: Firstly, we also use color histogram(CH) and histogram of orientated gradients(HOG) to represent the objects, model update is realized by kalman filter and gaussian model; secondly we use Gaussian Mixture Model(GMM) and Bhattacharyya distance to detect object appearance. Particle filter with combined features and model update mechanism can improve tracking results. Experiments on video sequences demonstrate that the method presented in this paper can realize multiple objects detection and tracking.
Impossible differential cryptanalysis is an analysis method by constructing impossible differential path, eliminating the keys satisfying this path, and finally recovering the secret keys. This paper has utilized a new property of Mix Columns Transformation, constructed a new 4-round impossible differential path, added 1-round and 3-round possible differential path before and behind this path respectively, and constructed a new 8-round impossible differential path. This path has been utilized to analyze 64-bit initial keys of 8-round AES-128, and this analysis method requires 2104 pairs of selected plaintexts, about 2105 memory cells and about 2107 encryption and decryption computation.
The use of digital library services within the network and the external aspects, analysis of university library network security risks faced by the hardware, software, security risk, technical risk, management risk and the risk of external attacks and other major security risk. Combination of network security technologies, were put forward their own coping strategies. Focus on analysis of hacker attacks and network viruses control methods, including the use of anti-virus protection software, the use of firewall technology, encryption and authentication technology, intrusion detection, VLAN technology, content inspection and monitoring technology, and virtual honey pot technologies. Library network systems only to achieve security of the nature of the equipment, Network technology, professional and management standardization, in order to effectively avoid the risk of a variety of network security and ensure the normal operation of network systems, research on prevention and control of universities Digital library network security risks with a reference and guide.
