摘要：纸是设计探讨半的一个有效、安全的答案的这的焦点在代理重新签名计划信任了问题，即，代理从用户 A 知道重新签名钥匙到用户 B ，他因此能翻译用户 A 做到用户 B 的任何签名，它损坏代理重新签名计划的必要要求(非否认性质)。在这份报纸，作者首先为阀值代理重新签名计划定义安全模型，然后基于 Ateniese-Hohenbergers 和 Shao-Cao-Wang-Liangs 途径建议二个阀值代理重新签名计划。

摘要：Strongly regular (α,β)-reguli are a class of incidence structures with given conditions which were introduced by Hamilton and Mathon. We introduce two classes of codes constructed from strongly regular (α,β)-reguli within PG(k-1,q). The codes are related with two-weight codes intimately.

摘要：Two kinds of lattice-basis reduction precoding schemes based on successive interference cancellation are *** successive interference cancellation(SIC) structure can be obtained by either orthogonal and a right triangular matrix(QR) decomposition,or the Vertical Bell Labs Layered Space Time(VBLAST) algorithm which provides optimal user ***,the extended channel approach is applied to the proposed SIC-based *** results show that the proposed schemes can achieve comparable BER performance to vector precoding(VP).

摘要：This paper deals with optimal training design and placement over multiple orthogonal frequency division multiplexing(OFDM) symbols for the least squares(LS) channel estimation in multiple-input multipleoutput(MIMO) OFDM ***,the optimal pilot sequences over multiple OFDM symbols are derived by co-cyclic Jacket matrices based on the minimum mean square error(MSE) of the LS channel ***,an enhanced channel estimation method using sliding window is proposed to improve further the performance for the optimal pilot sequences in fast-varying *** results show that the enhancedmethod can efficiently improve the performances for the optimal pilot sequences over two and four OFDM symbols,especially in fast-varying channels.

摘要：Radar cross section (RCS) reduction technologies are very important in survivability of the military naval vessels. Ship appearance shaping as an effective countermeasure of RCS reduction redirects the scattered energy from one angular region of interest in space to another region of little interest. To decrease the scattering electromagnetic signals from ship scientifically, optimization methods should be introduced in shaping design. Based on the assumption of the characteristic section design method, mathematical formulations for optimal shaping design were established. Because of the computation-intensive analysis and singularity in shaping optimization, the response surface method (RSM) combined genetic algorithm (GA) was proposed. The poly-nomial response surface method was adopted in model approximation. Then genetic algorithms were employed to solve the surrogate optimization problem. By comparison RCS of the conventional and the optimal design, the superiority and effectiveness of proposed design methodology were verified.

摘要：A semiautomatic segmentation method based on active contour is proposed for computed tomography (CT) image series. First, to get initial contour, one image slice was segmented exactly by C-V method based on Mumford-Shah model. Next, the computer will segment the nearby slice automatically using the snake model one by one. During segmenting of image slices, former slice boundary, as next slice initial contour, may cross over next slice real boundary and never return to right position. To avoid contour skipping over, the distance variance between two slices is evaluated by an threshold, which decides whether to initiate again. Moreover, a new improved marching cubes (MC) algorithm based on 2D images series segmentation boundary is given for 3D image reconstruction. Compared with the standard method, the proposed algorithm reduces detecting time and needs less storing memory. The effectiveness and capabilities of the algorithm were illustrated by experimental results.

摘要：Smoothed particle hydrodynamics (SPH) is a useful meshless *** first and second orders are the most popular derivatives of the field function in the mechanical governing *** methods were proposed to improve accuracy of SPH approximation by the lemma *** lemma describes the relationship of functions and their SPH ***,the error comparison of SPH method with or without our improvement was carried out.

摘要：An intelligent response surface methodology (IRSM) was proposed to achieve the most competitive metal forming products, in which artificial intelligence technologies are introduced into the optimization process. It is used as simple and inexpensive replacement for computationally expensive simulation model. In IRSM, the optimal design space can be reduced greatly without any prior information about function distribution. Also, by identifying the approximation error region, new design points can be supplemented correspondingly to improve the response surface model effectively. The procedure is iterated until the accuracy reaches the desired threshold value. Thus, the global optimization can be performed based on this substitute model. Finally, we present an optimization design example about roll forming of a "U" channel product.

摘要：The secure socket layer/ transport layer security(SSL/TLS) handshake protocol uses public key cryptographic algorithms such as RSA for key establishment. Typically, public key cryptographic algorithm is computational intensive due to the modular multiplications. Therefore, SSL/TLS servers often become swamped while performing public key decryptions when the simultaneous requests increase quickly. A batch RSA decryption algorithm was proposed. The novel algorithm provides the reasonable response time and optimizes server performance significantly. The decryption speedup is proportional to the batch size 6, for instance, the speedup factor is 4, while in Shacham's scheme the acceleration rate is only 2.5 when 6 = 4.

摘要：In concurrent engineering, effective process management is the key to improve the efficiency and quality of product development. Although in project management system, workflow management system and PDM system, process management functions are provided, they can not meet the needs of product development. In this paper, we integrate the project management, workflow management and product management technique together and a concurrent engineering oriented integrated product development process management system is proposed. The system structure, integrated product development model and running method are introduced. The practice proves this system is powerful in supporting product development process.