Advanced Materials Research Vols. 756-759

Abstract: Along with the computer technology in the examination of the application, the examination has become a hot topic. However, test paper is an important part of the adaptive test. According to the test generation of the objectives and requirements, this paper introduces a method based on item response theory ( IRT ) thought of genetic algorithm in the test application, thereby effectively solving the problem of intelligent test paper.

Abstract: For solving the linear system, different preconditioned iterative methods have been proposed by many authors. M-matrices appear in many areas of science and engineering. In this paper, we present preconditioned AOR-type iterative method and the SOR-type iterative method with a preconditioner for solving the M-matrices. In addition, the relation between the convergence rate of preconditioned AOR-type iterative method and the parameters are brought to light. Finally, a numerical example is also given to illustrate the results.

Abstract: This paper proposed a framework and an algorithm for identifying communities in dynamic social networks. In order to handle the drawbacks of traditional approaches for social network analysis, we utilize the community similarities and infrequent change of community members combined with community structure optimization to develop a Group-based social community identification model to analyze the change of social interaction network with multiple time steps. According to this model ,we introduced a greed-cut algorithm and depth-search-first approach and combine them to develop a new algorithm for dynamic social interaction network recognition (called ADSIN). In addition, we conduct experiments on the dataset of Southern Women, the experiment results validate the accuracy and effectiveness of ADSIN.

Abstract: As the main influence factors on price fluctuations of corn futures is more complex, so analyzing these factors that is very difficult. In this paper, China's consumer confidence index and consumer price index are selected as variables of the rational expectations so that the econometric model is created in multiple regression by EViews software. Finally, this paper forecasts the future developing trend of corn futures price, and it would have certain theoretical meaning and realistic significance.

Abstract: The power line communications (PLC) channel is noisy one, which can be modeled by the Markov process. The order is the key concerning when used the Markov process. the level of complexity will be incurred from using higher order , while the first-order Markov models may lead to the less accurate channel response. In the paper, the first-order Markov channel is under thoroughly discussion, and it can provide a mathematically tractable model for time-varying channels and uses only the received SNR of the symbol immediately preceding the current one. With the first-order Markov chain, given the information of the symbol immediately preceding the current one, any other previous symbol should be independent of the current one. We show that given the information corresponding to the previous symbol, the amount of uncertainty remaining in the current symbol should be negligible. That means the first-order of Markov process is enough when modeled the PLC channel.

Abstract: Recently, Hota et al. present a Capability-based Cryptographic Data Access Control in Cloud Computing. This scheme implements data storage, user authorization, data access and integrity checking. However, we find two fatal attacks in the data exchange between CSP and User. These attacks makes a registered user can intercept another legal users file and decipher it. To avoid these attacks, we give an improvement to Hota et als scheme and can resist theses attacks. Meantime, to make Hotas scheme be applicable, we propose a novel data access protocol in cloud computing. Our scheme guarantees data confidentiality and secure data access between User and CSP. Security analysis shows that the scheme can resist various attacks.

Abstract: Data simulation is an important auxiliary method for baseband signal processing algorithm design of digital IF GNSS receiver. Especially when the high sensitivity and high dynamic receivers are developed, or multipath and cross correlation mitigation techniques are considered, exact and complete tests under all kinds of necessary scenes can be carried out with the IF signal data which is generated by software simulation method. With this method, the developing efficiency can be improved and the cost can be cut down. In this paper, precise model of the IF signal is given firstly through analyzing GNSS receivers RF processing flow. Then, considering the discrete characteristic of software processing, the IF signal simulation flow and block of the simulation software are designed. Finally, the specific design process is given through a design example. When the IF signal simulation software is used for testing baseband signal processing algorithms, GNSS receivers IF signal data under every necessary test scene can be generated just by parameter adjustment.

Abstract: This paper aims at speeding up Batch RSA decryption. The performance of Batch RSA decryption has directs relationship with the efficiency of the full-sized modular exponentiation implementation in the Exponentiation Phase. This paper proposes a variant (BS1PRSA-Batch RSA-S1 Multi-Power RSA) to improve the Batch RSA decryption performance. The experimental results show that the speed of the decryption has been substantially improved.

Abstract: On the basis of discussing the basic features of rural power grid planning project and the status quo, this paper has constructed evaluation index system of the rural power grid planning project, and based on the characteristics of its particularity and indicators, established a fuzzy comprehensive evaluation model based on set pair analysis. It has carried on the comprehensive evaluation to some county in power grid planning project to verify the validity of the selected method. It will provide referential basis for the scientific decision of county power enterprises.

Abstract: On the basis of the basic theory of post evaluation of power transmission and transformation project in this paper, it selects the multi-level fuzzy comprehensive evaluation method to evaluate the project. Take the Qian Fangzi power transmission and transformation project as an example;It has carried on the empirical research. From the process of the project implementation, economic benefits, the influence of the project, sustainability evaluation and so on, it has achieved good results and proved the effectiveness of the proposed evaluation model.