信赖域算法的修订算法

为了求得非线性优化问题的最优解,必须从收敛的可能性和收敛速度入手实现有效的计算方法.为此,通过改变作为搜索方向的下降方向,并适当修订信赖范围,在信赖域算法的基础上提出了一种修订的最优化问题的求解方法.计算方法的计算程序虽然有些复杂,但从整体收敛性和计算可行性方面来说是一个有效的方法.     

A novel frequency-modulated differential chaotic shift keying modulation scheme based on phase separation

In frequency-modulated dierential chaos shift keying (FM-DCSK), the separation of the chaotic reference and information-bearing wavelets is performed in time domain. This separation method not only limits the attainable data rate but also demands delay components in transceiver circuits. Due to the fact that wideband radio frequency (RF) delay lines are extremely diffcult to implement with CMOS technology in ultra wideband communications, a new phase-separated FM-DCSK modulation scheme is presented in this paper to increase the data rate and to avoid the use of delay lines in both the transmitter and the receiver circuits. The feasible congurations of transmit- ter and detector are given. Besides, bit error rate (BER) performance of the proposed system is evaluated by both analysis and Monte Carlo simulations over additive white Gaussian noise (AWGN) channel.     

Bioperads and hopf bialgebras in cobordism theory

A construction of Dyer-Lashof operations for cobordisms of topological spaces is presented. Translated fromMatematicheskie Zametki, Vol. 65, No. 2, pp. 270–279, February, 1999.     

An integrated decision support tool for airlines schedule recovery during irregular operations

This paper presents a decision support tool for airlines schedule recovery during irregular operations. The tool provides airlines control centers with the capability to develop a proactive schedule recovery plan that integrates all flight resources. A rolling horizon modeling framework, which integrates a schedule simulation model and a resource assignment optimization model, is adopted for this tool. The schedule simulation model projects the list of disrupted flights in the system as function of the severity of anticipated disruptions. The optimization model examines possible resource swapping and flight re-quoting to generate an efficient schedule recovery plan that minimizes flight delays and cancellations. A detailed example that illustrates the application of the tool to recover the schedule of a major US air-carrier during a hypothetical ground delay program scenario is presented. The results of several experiments that illustrates overall model performance in terms of solution quality and computation experience are also given.     

Process selection and sequencing in a two-agents production system

This paper addresses a coordination problem concerning two production agents in a manufacturing system. The two agents have a set of processes which must be carried out on some common resource. They can use the resource individually, but in general there may be an overall advantage in concurrently performing certain processes. The problem is to select concurrent processes and to sequence them with the aim of minimizing the total number of set-ups. In particular, a decomposition approach is proposed, in which first the concurrent processes are selected, by solving a generalized network flow problem, and then an optimal process sequencing is efficiently found.AMS classification: 05C85, 90B10, 05C45Paper previously processed by Francesco Archetti for Ricerca Operativa     

Opérations d''Adams en K-théorie algébrique (Adams Operations and Algebraic K-Theory)

Following Schechtman's work on deloopings of Adams operations, we show that rational Quillen K-theory of schemes defines a special ring for schemes which are quasi-projective over an affine regular base.     

Natural discrete-event process forecasting: A decision support system

A decision support system for the analysis and forecasting of natural discrete-event processes is considered. The corresponding method is based on the sample path analysis using event-to-event operations. An application of the method in the computer-aided decision support system for the long-range weather forecasting is mentioned.     

一种改进的在Hessian曲线上计算Tate双线性对的算法

选择适当的椭圆曲线,对于快速部署和实现椭圆曲线密码系统具有重要的意义.由于Hessian形式的椭圆曲线可以运用并行算法快速实现点加和倍点运算,因此能够有效提高系统的实现效率.利用Hessian曲线上点的优良性质,简化了直线斜率的计算公式,优化了在Hessian曲线上计算Tate双线性对的算法.在其他运算量保持不变的前提下,改进后的算法使点加和倍乘运算的运算量分别降低13.43%和11.25%.     

配置柔顺机构空间机器人双臂捕获卫星操作力学模拟及基于神经网络的全阶滑模避撞柔顺控制

讨论了空间机器人双臂捕获卫星操作过程避免关节冲击破坏的避撞柔顺控制问题. 为此在关节电机与机械臂之间设计了一种旋转 型串联弹性执行器(rotatory series elastic actuator, RSEA)--柔顺机构,其作用在于:(1) 通过其内置弹簧的拉伸或压缩变形来吸收捕获操作过程中被捕获卫星对空间机器人关节产生的冲击能量;(2) 可以利用合理设计的与之配合的避撞柔顺控制策略来保证关节冲击力矩受限在安全范围. 首先,利用第二类Lagrange方程分别建 立了捕获操作前含柔顺机构双臂空间机器人的开环分系统动力学模型与目标卫星的分系统动力学模型;之后,基于系统动量 守恒关系、闭链系统位置与速度几何约束关系,获得了捕获操作后空间机器人与被捕获卫星闭链混合体系统综合动力学方程; 最后,基于RBF神经网络提出了一种捕获操作后两者混合体系统镇定运动的全阶终端滑模避撞柔顺控制方案. 所提方案结合柔 顺机构在有效吸收、缓冲被捕获卫星冲击能量的同时,还在冲击能量过大时适时开、关空间机器人关节驱动器,以避免关节驱 动器过载、破坏;此外,还通过最小权值范数法分配了机械臂各关节力矩,以保证双臂协调操作. Lyapunov稳定性理论证明了 系统的全局稳定性,系统计算机数值仿真也验证了上述避撞柔顺控制策略的有效性.      

On the algebra of handle operations in 4-manifolds

The possibility is considered that the Andrews-Curtis conjecture, if false, may provide obstructions to the cancellation of 1- and 3-handles in a simply connected 4-manifold. An algebra is developed for the simultaneous algebraic reading of attaching maps for 2-handles and their duals, and it is shown that obstructions to 1- and 3-handle cancellation cannot bedetected in this algebra.