一种语音混沌保密通信方案的研究与硬件实现

在硬件实验研究的基础上，建立一种环形蔡氏电路，提出用环蔡氏电路实现语音混沌保密通信的一种闭环逆系统方案，其特点是利用环形蔡氏电路的单向耦合原理，通过反馈的方法形成一个包括有用信号在内的极联闭合环路，从而实现改善端与接收端之间混沌系统的严格同步而不受有用信息调制的影响。理论分析与硬件实验结果证明，该方案同现有的其它混沌通信方案相比较，具有非线性失真小、保真度高的优点，完全能够满足传送语音信号的要求。     

测距仪中新型的脉冲激光光源

针对现有测距仪中脉冲激光器存在寄生多脉冲的问题，提出并实现新型的采用同步泵浦声光调Q方法的测距仪用激光器、消除了寄生脉冲并提高了激光器的峰值功率。     

宽带线性调频信号产主技术研究

本文介绍了采用数字基带产生结合倍频链扩展带宽的方法设计与实现了大带宽线性调频信号产生系统。详细分析研究了实现系统的三项关键技术，给出并分析了相应环节的输出信号。对系统进行了预失真补偿处理，成功实现了ＶＨＦ／ＵＨＦ波段、带宽达３００ＭＨｚ线性调频信号的产生。经脉冲压缩处理，主瓣旁瓣比（ＰＳ１Ｒ）在－３７ｄＢ以下。     

A novel compact circuit for 4-PAM energy-efficient high speed interconnect data transmission and reception

Transmission of signals, whether on-chip or off-chip, places severe constraints on timing and extracts a large price in energy. New silicon device technologies, such as back-plane CMOS, provide a programmable and adaptable threshold voltage as an additional tool that can be used for low power design. We show that one particularly desirable use of this freedom is energy-efficient high-speed transmission across long interconnects using multi-valued encoding. Our multi-valued CMOS circuits take advantage of the threshold voltage control of the transistors, by using the signal-voltage-to-threshold-voltage span, in order to make area-efficient implementations of 4-PAM (pulse amplitude modulation) transceivers operating at high speed. In a comparison of a variety of published technologies, for signal transmission with interconnects of 10-15 mm length, we show up to 50% improvement in energy for on-chip signal transmission over binary encoding together with higher limits for operating speeds without a penalty in circuit noise margin.     

化工软测量技术研究进展

详细说明了软测量技术的含义以及软测量系统的组成。在此基础上，介绍了软测量技术中基于机理分析建模、应用状态观测器建模、应用统计分析建模、神经元网络、模糊技术、以及支持向量机的智能建模等软测量建模理论方法和最新研究成果，之后介绍了小波分析、推断控制算法在软测量数据处理中的应用，最后介绍了基于虚拟仪器开发平台的软测量系统实现技术。     

基于地理信息系统的天津房地产管理数据库

从地理信息系统CIS的组成开始．提出该类系统的组织与管理方法，同时重点介绍了在现阶段开发该类系统时所使用的高端技术，最后对GIS系统的发展趋势作出分析与顶测。     

Forced Vertical Vibration of Circular Plate in Multilayered Poroelastic Medium

This paper considers the vertical vibrations of an elastic circular plate in a multilayered poroelastic half space. The plate is subjected to axisymmetric time–harmonic vertical loading and its response is governed by the classical thin-plate theory. The contact surface between the plate and the multilayered half space is assumed to be smooth and either fully permeable or impermeable. The half space under consideration consists of a number of layers with different thicknesses and material properties and is governed by Biot’s poroelastodynamic theory. The vertical displacement of the plate is represented by an admissible function containing a set of generalized coordinates. Contact stress and pore pressure jump are established in terms of generalized coordinates through the solution of flexibility equations based on the influence functions corresponding to vertical and pore pressure loading. Solutions for generalized coordinates are obtained by establishing the equation of motion of the plate through the application of Lagrange’s equations of motion. Selected numerical results are presented to portray the influence of various parameters on dynamic interaction between an elastic plate and a multilayered poroelastic half space.     

Breaking the search space symmetry in partitioning problems: An application to the graph coloring problem

Many problems consist in splitting a set of objects into different groups so that each group verifies some properties. In practice, a partitioning is often encoded by an array mapping each object to its group numbering. In fact, the group number of an object does not really matter, and one can simply rename each group to obtain a new encoding. That is what we call the symmetry of the search space in a partitioning problem. This property may be prejudicial for optimization methods such as evolutionary algorithms (EA) which require some diversity during the search.     

A stochastic realization algorithm via block LQ decomposition in Hilbert space

A stochastic realization problem of a stationary stochastic process is re-visited, and a new stochastically balanced realization algorithm is derived in a Hilbert space generated by second-order stationary processes. The present algorithm computes a stochastically balanced realization by means of the singular value decomposition of a weighted block Hankel matrix derived by a “block LQ decomposition”. Extension to a stochastic subspace identification method explains how the proposed abstract algorithm is implemented in system identification.     

强磁防蜡器工艺改进措施

针对影响强磁防蜡器两个性能指标的关键要素进行分析，设计并制造了专用的模具和采用水浸式焊接新工艺，提高了产品性能，产品质量的稳定性有了可靠的保证，同时加工成本也有较大幅度的下降。