天津市科技特派员制度长效运行机制探索

为探索建立天津市科技特派员制度的长效运行机制,本文深入分析了天津市科技特派员工作的发展和现状,并结合其工作效果,从农业科技成果转化的角度入手,详细阐述了宏观调控机制、供求均衡机制、人才流动机制、利益驱动机制、风险防范与补偿机制以及信息传递机制等六大机制对科技特派员制度长期运行所发挥的作用和产生的重大影响,最后对天津市科技特派员工作长效机制提出了相关政策建议。     

Equivalent Duffing System Method of Nonlinear System Dynamic Reliability Analysis

Equivalent linear system method is the main method of nonlinear structural system random response analysis. While it would generate big error when the results of equivalent linear system method are used to analyze the structural dynamic reliability. Through minimum mean square error principle, general nonlinear system was converted to equivalent Duffing nonlinear system, based on which the structural dynamic reliability was analyzed. The accurate steady state analytic solution of Duffing nonlinear system can be worked out by FPK equation, so it is not only convenient but also accurate to analyze structural dynamic reliability by using the equivalent nonlinear system method. It is also shown that the analysis results of equivalent nonlinear system method presented here is reliable and the calculation accuracy is higher than equivalent linear system method apparently through the example analysis.     

The Location Algorithm of QRS Waves Based on Fractal Box Dimensions Detection Methods

We research fractal characteristics of ECG signal, and find that it is logarithmic linear relationship between the boxes number covering signal and box scale. It is shown that ECG signal have some characteristics. Further more, we discover that fractal dimensions at QRS site are higher than others when using a time windows to detect signal. Based on this foundation, we raise a location algorithm of QRS waves which is based on fractal boxes dimension detection methods. The application results of this algorithm show that it can get rid of noise in ECG effectively with high speed, so this algorithm can be used in real time detection of ECG signal.     

粮仓窗户远程自动控制系统设计

设计出一种粮仓窗户远程自动控制系统。根据仓内外的温度和湿度变化,自动开启或关闭窗户及通风机械,实现粮仓的自动通风,自动控制。该系统可与粮情检测系统、通风控制系统等结合,组成粮仓自动化管理系统。     

Machine Vision Aided Testing System for Flatness Based on Equal Inclination Interference Theory

An approach is described on the automated tracking of interference circle fringe to get the flatness accurately based on the Equal Inclination Interference Theory (EIIT). The system,based on the theory of EIIT, can be applied to grasp the changing fringe information, which is white alternating with black through the CCD camera. Following the basic principle of fringes image centro-symmetric, we create some windows, process only the interference fringes information in the windows. According to the position of the processed interference fringe and the position of the last adjacent interference fringe in the windows, the interference fringe variation value N from the starting measured point is received, it implies the changed altitude value from the starting measurement point. This method allows us not only get the fringe information of the half-wavelength integer multiple but also denote those of the half-wavelength decimal multiple. The system is proved to be effective experimentally. It is useful in metrology department for the high-precision flatness standard unit.     

THE APPLICATION OF TNE SPATIALLY MECHANICAL THEORY OF ROBOT

A kinematic simulation model has been designed for a cantilever manipulator ofhydraulic exacvator and the kinematic performance of a 20 t hydraulic excavator' s cantilever ma-nipulator is simulated on IBM-PC/XT microcomputer.     

Existence and Stability of Periodic Solutions for Reaction-diffusion Systems with Time Delays

Periodic solutions of reaction-diffusion systems with time delays are investigated. It is constructed that the - per and lower control function of nonmonotone reaction term, and it is showed that the function satisfies a global Lipschitz condition and quasimonotone. A sort of effective method of studying differential equation with nonmonotone reaction term is gained. By using the method of upper and lower solutions and fixed point theorem, it is shown that periodic solutions of this system exist when reaction-term is not monotone and the boundary value system has a pair of coupled-upper and lower solutions. Some methods for proving the stability of the periodic solution are also given. And some known resuits are extended.     

Simulation Research of Control Parameters in Induction Motor Vector Control System

In order to obtain the effect rules of control parameters of speed regulator on performance indexes of induction vector-controlled system and the setting rules of control parameters of speed regulator,according to rotor flux oriented control principle,a vector control model of induction motor is established and simulated with the software of Matlab/Simulink.This vector control system is proved that it possesses good static and dynamic performance.This paper analyzes the effect of control parameters' variations of speed regulator on performance indexes and gives simulation results.     

Chaotic Synchronization of Discrete Nonlinear Systems on Different Parameters for a Kind of Systems

According to the theory of parameters adaptive control and variable driving, for a kind of discrete nonlinear chaotic systems, a method of chaotic synchronization is presented for different system parameters. In the equation of parameters adaptive control, control coefficients are chaotic signal. Because control coefficients are constant usually for the former parameters adaptive control, so the parameters adaptive control method is very universal, namely the former parameters adaptive control methods are special examples in our control method. Simulation results show that this method is available.     

Analysis of Elevated Structure Radiated Noise with BEM-FEM Method

Urban rail transit is becoming an important means of transportation and elevated structure is one important part of urban rail transit. So the radiation noise induced by elevated structure attracts more and more attention. Based on the theory of Helmholtz integral equation of BEM and fluid-structure coupling system of FEM, the sound pressure transmission vector reflecting the relation between structural vibration acceleration and radiation of sound pressure is derived and solved by the element radiation superposition method. The calculated results are in good agreement with the experimental data from a viaduct section of the Beijing airport rapid rail transit.     

Distributed Power Flow Method Based on Ward Equivalent

With interconnecting and developing of power system, the problem of power flow computation on dispersed data resource need to be solved. A new distributed computation method of power flow based on Ward equivalent is presented. According to master-slaver splitting principle, multi-area interconnected power system is divided into master-slaver areas. Boundary buses in different areas are defined as different bus-types. Neighborhood areas are equivalent by Ward equivalent principle, and the equivalent injection power and equivalent impedance are worked out. Power flows from master area to slaver areas are solved by Newton method, and the equivalent injection power and equivalent impedance on the boundary are modified by their solutions. The process above repeats until to convergence. The proposed distributed power flow method takes full advantage of the information of power, voltage, network configuration in neighborhood areas, so it is better on convergence and quality of solution. The proposed algorithm is testified by IEEE 14-bus system and a practical 181-bus system.     

走向2020年的中国农业科技

在系统回顾中国农业科技的事业发展阶段性成果与成就的基础上,立足现代农业对科技的现实和未来发展需求,对新时期中国农业科技发展进程中面临的问题与挑战进行了分析,提出了农业科技发展的短期目标和未来农业科技发展的优先领域和战略重点,并提出了农业科技发展的措施和政策保障。     

Controlling Model of Company''s Financial Index

In a mature, standard and perfect securities market, with the interaction relationship each financial data, we build a model of a union equation. In terms of the data of years data, we can estimate the parameters of the theory of financial control, the managers and investors can control reasonably the process to the object of financial measures system, through some relevant financial measures data. In the opposite, they also can calculate the financial measures data of the firm by the optimum controllable variable.     

Garlerkin Boundary Element Method with Hyper Singular integral kernel

A Galerkin Boundary Elements was applied to solve the first kind of integral equation with hyper-singularity, which can be deduced from the direct boundary integral formula for the Neumann problem of Laplace equation. The concept of integration by parts in the sense of distributions was used. When boundary rotation is introduced, the two order derivatives of singular kernel are shifted to the boundary rotation of unknown function in the Galerkin variational formulation. While linear boundary elements are used for 2-dimensional problems, the boundary rotation on each element can be discretized into a constant vector, so that the integration can be performed in a simple way and the difficulty of numerical calculation for hyper-singularity is overcome. The results of numerical examples demonstrate that the scheme presented is practical and effective.     

Application and Development of Chemometrics in Ink Analysis

Ink analysis is an important part of material evidence analysis in forensic science. It not only needs to acquire data by precise chemical analysis instruments, but also needs to parse data by the chemometrics methods such as principal component analysis (PCA), cluster analysis (CA), artificial neural networks (ANN) and pattern recognition and so on. The main applications of chemometrics in ink synthesis, including experimental design and optimization, signal processing, multivariate calibration, pattern recognition, database technology and expert system, have been reviewed. Furthermore, future trends of ink analysis are prospected.     

Nonlinear Science and Control about the Geological Hazards in the Three Gorges Reservoir Area

Such the geological hazards as landslide, rockfall, debris-flow and so on frequently occur in the Three Gorges Reservoir Area, so it is a very practical and immediate job to explore the mechanism caused the geological hazards and how to forecast and control the geological hazards. For this reason, this paper introduces the situation of the geological hazards occurred in the Three Gorges Reservoir Area and the major type and feature of the geological hazards occurred in Chongqing, and discusses the basic principle about the modern nonlinear science applied to the geological hazards and the creep-slip, stick-slip occurred on the joints of rock mass and the monitoring technology of the geological hazards.The basic thinking is put forward which can be applied the modern nonlinear science to the geological hazards occurred in the Three Gorges Reservoir Area.     

基于无线传感器网络的鱼塘监控系统

本文设计了基于无线传感器网络的鱼塘实时在线智能监控系统,有效解决了传统的鱼塘观测手段存在的问题,例如：费时费力、步骤复杂、成本高等。该系统在鱼塘的监测区域中利用无线传感器节点,测得该区域中的温度和溶氧量,并通过Zigbee网络将数据传输到终端控制系统,控制系统作出判断并发出报警信号和控制增氧机的状态。系统中以MSP430和XBEE模块为核心芯片,能够实时在线监测鱼塘中的一些参数,例如温度、溶氧量等。同时该系统还可以进一步扩展使用GPRS或3G网络实现远程监控。     

农业科技评价及其问题与建议

农业科技评价是指根据委托者的明确目的,由专门的评价机构和人员依据大量的客观事实和数据,遵循一定的原则、程序和标准,运用科学、可行的方法,对科技政策、科技计划、科技发展领域、科技项目、科技成果、科技机构、科技人员以及与科技活动有关的行为,进行专业化咨询与评判的活动。其目的在于减少农业科技决策的盲目性和随意性,有重点、有效率地分配农业科技资源,改善和提高农业科技决策的质量和水平,通过公开、透明的评价标准、程序及评价结果,接受各方监督,创造民主、公平、竞争的农业科研环境。农业科技评价具有9项功能,需要遵循8项标准。当前农业科技评价存在的主要问题是：评价大多只注重一头一尾,而缺乏对科技活动本身的过程性评价和整体性评价;第三方评价制度亟待建立;定位不够明确;评价能力有待提高;评价指标体系存在误区。为此,建议采取以下对策：落实科技评价相关规定,建立健全农业科技评价管理制度和操作规范;建立健全农业科技评价支持系统,培育农业科技评价人力资源;加强对符合农业科研现状的评价指标体系和方法的研究;评价工作要抓全程;建立健全农业科技评价激励制度,充分发挥评价的激励作用;建立与国际接轨的农业科技评价制度。     

河北接坝冷凉地区时差菜产业发展的关键与对策

河北接坝冷凉地区,被省政府列为无公害时差蔬菜生产基地。蔬菜产品数量、质量和市场占有率均有较强优势。但是,通过对时差蔬菜产业现状分析,仍然存在时间差未发挥优势、品种单一,科技含量低,营销体系不健全、产品精深加能力差、集约化生产能力低等制约因素。因此,必须采取加大新品种、新技术引进推广力度,加大投入和招商引资力度,强化监管部门的职能和推广综合化服务先进模式,加强流通体系建设,实现规模化、标准化、系列化生产经营模式,增强品种意识,形成品牌优势等策略。完善中介组织,创办产业协会,通过政府扶持,开通绿色通道,促进时差蔬菜产业发展。     

The Operator Solution of Liouville-Hill Equation and Its Applications

With operator solution. recursion formula of series solution to Liouville-Hill equation is given, furthermore the paper discusses the remainder term of the series and its estimation. and the existence and uniqueness of the solution is obtianed. Next,we discuss the inital problem of the n on homogeneous Hill equation with damping terms, which is a forced oscillation problem, and the series sloution and the sufficient conditions of its convergence are also given.