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Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Poyang Lake is the property of Journal of Poyang Lake Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The blow-up problems of the solutions are considered for reaction-diffusion equations with nonlocal sources and variable exponents. Firstly, the local existence and uniqueness of solutions to the problem were proved under the fixed-point theorem. Secondly, by means of the super- and sub-solution method, some sufficient conditions for the occurrence of finite-time blow-up were determined under the homogeneous Dirichlet boundary conditions, i.e., the variable exponent is positive and the initial value is large enough. Moreover, the estimates of upper and lower bounds of the blow-up time were given. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University (Science Edition) is the property of Journal of Zhejiang University (Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the cloud environment, the data access policy based on the traditional attribute-based encryption (ABE) technology in the session key agreement protocol cannot reflect the complex relationships of many attributes, which leads to the lack of user authentication ability and the flexibility. To solve the problem, this paper presented a user authentication structure of linear secret sharing scheme (LSSS) based on the attached condition expression of complex attribute relations, and introduced an attribute-based key agreement protocol based on the structure. The protocol realized a more general user authentication policy based on user attributes, maintained the fuzzy identity authentication feature, and provided the exchange of session keys between the users who both met the conditions of the attribute relationships. Under the attribute-based Blake-Johnson-Menezes (AB-BJM) model, the security model of selective access structure and the decisional q-parallel bilinear Diffie-Hellman exponent (q-PBDHE) hypothesis, the protocol proves to be secure. Compared and analyzed the similar protocols through experiment, the protocol has better performance in the application scenarios containing the more complicated relationships of attributes, and has wide application prospect. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Sunyatseni / Zhongshan Daxue Xuebao is the property of Sun-Yat-Sen University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An efficient method was developed to determine the first- and high-order terms of asymptotic solutions of plastic stress and displacement near V-notch tips under anti-plane shear in power-law hardening materials. Through introduction of the asymptotic series expansions of stress and displacement fields around the V-notch tip into the fundamental equations of the elastoplastic theory, the governing ordinary differential equations (ODEs) with the stress and displacement eigenfunctions were established. Then the interpolating matrix method was employed to solve the resulting nonlinear and linear ODEs. Consequently, the high-order stress exponents and the associated eigen-solutions were obtained. The presented method, being capable of dealing with the V-notches with arbitrary opening angles and strain hardening indexes under antiplane shear, has the advantages of great versatility and high accuracy. Typical examples were given to demonstrate the accuracy and effectiveness of this method. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using the high-dimensional complex chaotic system in the chaotic ultra wideband signal can enhance the security of the signal,but reduce the easy implementation of the chaotic system.In view of the contradiction between the complexity and the easy realization of the chaotic system used in the chaotic ultra wideband(UWB),this paper designed a chaotic system with low dimension and easy to implement by using two one-dimensional chaotic maps with easy implementation based on chaos branch switching and embedding.Lyapunov exponent analysis shows that it is chaotic in a wide range of parameters.The analysis shows that the signal generated by the system cannot reflect the definite mapping relation,which not only increases the complexity of chaotic signal,but also makes the system easy to implement.The analysis also shows that this chaotic signal has good correlation.Therefore’ this paper also generated more secure chaotic time hopping UWB signal based on this chaotic system.At the same time,through the comparative analysis of the power spectrum of the chaotic UWB signal and the general pseudo-random time hopping UWB signal,it contains less discrete spectrum which can produce interference to other transmission systems,and also makes the chaotic UWB signal have more extensive application fields. [ABSTRACT FROM AUTHOR]

In order to adapt to the use of resource-limited devices such as mobile phones in the cloud environment and reduce the computation and communication cost of the session key protocol based on multi-authority attribute-based encryption, this paper proposed a protocol that generated exchange messages with ciphertexts of constant length. This protocol visited data on the basis of the multi-value access structure, which strengthened the controlling abilities of the data owners over the system. Under attribute-based Blake-Johnson-Menezes( BJM ) model and selective access structure security model, the protocol made security proving based on q parallel Diffie-Hellman exponent( q-PBDHE) hypothesis. The experimental results show that the proposed protocol has lower computational and communication costs and is suitable for the application of resource-constrained devices. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To increase the performance of throughput for 802. 15. 4 network, this paper designed an improved process of node state transition. Moreover, it proposed a model of node access channel considering the hidden terminal problem and retransmission, and it carried out the analysis and calculation of model. Based on the calculation results and the analysis of channel state model, then, it gave out the derivations of the data collisions probability, packet lost rate and throughput channel con side ring the hidden terminal problem. Finally, this paper studied the impact of packet arrival rate, back off exponent and hidden terminal on the performance of network throughput. Experimental results show that, compare with 802. 15.4 network without retransmission mechanism, the network throughput is increased by 83.9% or so. Compare with the sleep methods under some conditions, the network throughput is increased by 13.3 % on average, the proposed model can effectively improve network throughput performance . [ABSTRACT FROM AUTHOR]

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to reduce the packet lost rate in 802.15.4 MAC layer, this paper raised a model of channel competition mechanism based on Markov chain by analyzing the reason of packet loss rate. Then, throught the mathematical derivations of the steady-state probability on the network transmission, backoff and the channel detection state based on the model of channel access, this paper discussed the formulas of channel collision and the frame packet lost rate. Finally, this paper studied the impact of protocol parameters such as packet arrival rate, the number of nodes, bit error rate, backoff exponent, and number of backoffs on the collision probability and the packet lost rate. Experimental results show that, compared with IEEE 802. 15.4 network without node sleep state, the packet lost rate is reduced by 23. 7%. And the model describes the MAC layer channel access mechanism very well, and reasonable settings for parameters can optimize the frame packet lost rate. The research outcome can provide reference for the reliable transmission optimization in the practical application of wireless sensor network. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of scale-free network’s topology features on network robustness, combining two indexes of node’s betweenness and edge’s weight, which had important influence on network robustness, this paper proposed a tunable scale-free network attack method with cost. This method considered the attack cost of nodes(edges) when the network was attacked. The method used the node’s betweenness(edge’s weight) to approximately measure the cost of nodes(edges). This method used different attack strategies of nodes(edges) to attack the network. And this method used the largest component to quantify the network robustness. By using the method, this paper investigated the relation between scale-free network’s power-law exponent, average degree and network robustness. When adopting the intentional attack strategy and fixing the cost value of nodes(edges), the experimental results show that the lower the power-law exponent of scale-free networks or the higher the average degree of scale-free networks, the more robust of the network. The simulation results verify the effectiveness and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper. we consider quasilinear elliptic systems with both critical Sobolev-Hardy exponents and concave-convex nonlinearities in bounded domains. By using variational methods and Nerahi manifolds. the multiplicity of positive solutions to this problem are obtained. [ABSTRACT FROM AUTHOR]

Based on the original sequence for non-homogeneous exponential of the grey derivative of GM(1,1) model, this paper uses forward difference quotient and backward difference quotient of the weighted average as the grey derivative of the GM(1,1) model, and gives the concrete expression of the weighted coefficient λ to establish the new optimized grey derivative of GM(1,1) model, which adapts to the non-homogenous exponential sequence. This paper proves that this model possesses white exponential law coincidence, gives a method to solve parameters and gets expression of parameters. The examples show this model has higher precision and can completely fit for strict non-homogeneous index series. [ABSTRACT FROM AUTHOR]

For the generating and modeling problem of accumulated sequences in opposite-direction, this paper has analyzed the quasi-smoothness and quasi-exponentially law of accumulated generating sequences in opposite-direction, and given the grey modeling conditions for such sequences. Besides, this paper has proved the relationship of homogenous and non-homogenous discrete exponential functions based on accumulated generating operation in opposite-direction, and after a series of theoretical analysis, the optimized background value of GOM(1,1) model has been given. The result shows that the optimized background value and the time response function of GOM(1,1) model have a better consistency, thus it can effectively improve the accuracy of the traditional model in theory. Finally, two applications are given to demonstrate the practicability and effectiveness of the optimized model. [ABSTRACT FROM AUTHOR]

The extended weighted and object functions are proposed based on the time-to-go exponential function. The optimal control theory is used to deduce a family of extended optimal trajectory shaping guidance laws for the constant maneuvering target. According to Schwartz inequality, the analytical solution of the guidance law acceleration command is derived by introducing the initial displacement, initial heading error, target maneuver and final impact angle into the lag-free guidance system. The analysis shows that the final acceleration command approaches to zero when the exponent of the time-to-go exponential function is greater than zero. The non-dimensional position and angle miss distance of guidance system with first order lag are studied using the non-dimensional method and the adjoint method. The results show that the position and angle miss distance induced by the heading error and final impact angle approach to zero when the missile terminal guidance time is about 15 times of the system lag time constant. And also, the position and angle miss-distance are smaller when the signs of initial heading error angle and final impact angle are opposite. [ABSTRACT FROM AUTHOR]

Most of the scaling exponents in real network are scattered between 2 and 3, while the exponent of BA network is 3 constantly. Based on the BA model,the preferential attachment mechanism between the existing vertexes is imported and a scale-free network whose scaling exponent can change in some certain scope is proposed. The degree distribution is calculated analytically and the analytical results indicate that the scaling exponent varies from 2 to 3 under different values of the parameters. It is also pointed out that the BA network model is the particular case of the model. And through the analyses of some data of the real networks,the model is proved to be reasonable and effective. [ABSTRACT FROM AUTHOR]