Researches and Advances in Structural Damage Dynamic Identification Technology

This paper describes the theory and research progress of dynamic structural damage identification technique of the last twenty years.The basic theory of dynamic structural damage identification techniques is introduced first.Next,three important aspects of damage identification are discussed: identification mechanisms,dynamic parameters,and identification algorithms.Finally,a review of the state-of-the-art and development trends in this field is presented.     

农田杂草抗药性检测鉴定方法

化学除草剂的大面积使用,解决了农田草害的主要问题,极大的推动了农业生产和除草剂化学工业的发展。但是,随着除草剂使用面积和用量的不断提高,杂草抗药性已日益成为除草剂应用和农业生产面临的一个突出问题。目前对抗药性杂草的发生和分布、生物学特性、抗性机理、鉴定技术以及抗药性杂草的综合治理等方面进行了大量的研究。其中,杂草抗药性的鉴定是其综合治理的前提,因此也是最为重要的内容之一。本文对杂草抗药性的鉴定方法,如温室整株植物测定法、生理生化测定法以及DNA分析技术等进行介绍,并对这些技术的优缺点进行分析。     

动物标识发展趋势及其应用于畜禽管理的对策研究

文章以动物标识技术的演进过程及其在畜禽品种选育、精准养殖管理、畜禽疫病防治、动物产品安全及畜禽国际贸易中的应用现状及所面临的发展瓶颈和制约因素为依据,提出国际标识技术在提高信息采集精准性、降低技术应用成本和实现技术标准国际兼容性等方面的发展趋势,在此基础上,总结我国动物标识及可追溯系统建设面临的问题,并从技术研发和运行管理两个层面提出促进动物标识技术应用于我国畜禽管理的对策建议。     

DNA标记在植物品种鉴定上的应用现状

为了全面地了解DNA指纹在品种鉴定上的利用现状,更重要的是促进DNA指纹技术切实有效的应用于植物品种鉴定,本研究归纳了目前开发出的可用于植物品种鉴定的DNA指纹技术,指出已有的DNA指纹品种鉴定技术的优势与不足,总结了DNA指纹应用于品种鉴定的分析措施,并认为受限于缺乏可以将DNA指纹转化为植物鉴定信息的理想措施,所以DNA标记还未真正有效地应用于生产实践中,因此提出一种基于DNA指纹的人工绘制品种鉴定简图(MCID)法是很重要的,本研究也重点阐述了MCID法的实施过程。     

Security Condition and Countermeasures of the Information Integrated Platform in Manufacturing Enterprises

Information integrated platform in manufacturing enterprises is a kind of software and hardware platform which supports application development, application integration and system running in complex information environment. The information processing of enterprises relys on this platform. Due to the increasing number of computer security problems, much attention must be paid to the security of information-integrated platform in manufacturing enterprises. The current security condition of information-integrated platform in manufacturing enterprises is introduced and the related countermeasures is also produced. In order to ensure the security, the conclusion that secure management system should be combined with secure management techniques is drawed .     

Adaptive Inverse Control for Feed Water and Superheated Steam Temperature of Supercritical Pressure Boiler

An adaptive inverse control method for feed water and superheated steam temperature of supercritical pressure boiler is investigated. Through the analysis of the boiler system ,s dynamic characteristics, the input vector structure of inverse dynamics model of feed water and superheated steam temperature is constructed. The adaptive inverse control system is realized through on-line identification of inverse dynamic model with recursive least squares support vector machine. In the control process, the demand for feed water and spray water flow to the outlet steam temperature and micro-superheated steam temperature is considered to realize the integrated control of feed water and superheated steam temperature. Simulation results show that this control system has good control performance and adaptability and can void the repeated oscillation phenomena of control variables which appear in present two section control system.     

Design of Excitation Control System of A.C.Excited Generator

Dual-passage excitation control method based on dynamical synchronous reference frame is analysed according to the base theory of A.C. excited generator. Using the dual-CPU project basing on the high speed DSP, excitation control system of A.C. excited generator is realized. Considering the characteristic of this control system, taking full advantage of the high speed and the convenient peripherals of DSP, the hardware and software of the control system are designed appropriately. Dual-passage excitation control system is realized using the dual-CPU method. Dual-passage excitation control strategy based on dynamic synchronous reference frame is proved with the experiment.     

Application of liquid crystal display in the field of dynamic wave display

It is a very important task that using a liquid crystal display module to replace the computer monitor and realizing the dynamic display of wave and data without dithering. The paper describes the way to process sampling data using synchronous technology, to transform data and to find unknowable coordinate. The transforming of address and the drawing of wave and the scrolling of wave are introduced. The dots link up with each other and the wave has no dithering. The dynamic wave and static parameter can coexist. The engineering application shows that the method is effective and economical.     

ANALYSIS OF THE DYNAMIC STABILITY OF DUALEXCITED SYNCHRONOUS GENERATORS WITH NON-DAMPING WINDINGS

This paper analyses in detail the dynamic stability of thedual-excited synchronous generators with non-damping windings,and sets up theundamental equations and the linearized mathematical model for small distur- bance analysis.By an example with computer results,the paper also compareshe difference of the dynamic stabilities between the single-and dual-excited synchronous machines,which explains that the dual-excited synchronous gene- rators can increase the dynamic stability of machines under certain conditions.     

Dynamic Simulation for Hydraulic Pressure AGC of Rolling Mill

AGC control technology is one of the key techniques used in modern rolling mill, the effect of which has influence on the accuracy of the product. On the base of analysing system composition and dynamic characteristics of the main dynamic emelent, a danamic simulation model is put forward,and then dynamic simultion for the hydraulic AGC system of 3340 rolling mill is implemented. Then, it lays a foundation for the design of rolling system and the dynamic simulation of the rolling process.     

Control Strategy for Asychronized Turbogenerators

Asynchronized Generator can better solve the excessive reactive and stability problem in power system.In order to improve the dynamic and transient performances of an asynchronized turbogenerator(ASTG),excitation control equation of it in the dynamic synchronous reference frame is presented.Control results are simulated in the synchronous and dynamic synchronous reference frames for ASTG.It is shown that the dynamic and transient performances in the dynamic synchronous reference frame are better than those in the synchronous reference frame.Consequently,the control strategy of dynamic synchronous reference frame can shorten more time on the dynamic process of ASTG.     

Fuzzy Identification on Mathematical Model of Dynamic Process of Evaporator in Refrigeration System

Founding the mathematic model of refrigeration system's dynamic process is the basis of realizing the optimal control of refrigeration machines.Refrigeration evaporator is a kind of two-phase flow and heat exchange with complex process.For its obvious nonlinearity and uncertainty,it is difficult to describe by accurate theoretical model.This paper partitions the input data into some clusters by entropy method and competitive learning algorithm,then the on-line fuzzy identification of dynamic process mathematical model of evaporator is achieved by utilizing ultimate parameter which is ascertained by the recursive least-square(RLS).The simulation results show that fuzzy identification method is effective for on-line model process of evaporator in refrigeration system.The model has not only superior identification precise,but also quite perfect generalizable performance and traceable ability.     

Study on constant current control of inductive power transfer with parameter identification

Aiminy at magnetic exciting current (resonant current) control, a constant current control method based on dynamic parameter identification is put forward. With energy conversion analysis, the energy storage, supply and dissipation functions of the system resonant network are constructed. The reflecting impedance identification functions are obtained by constructing the energy equilibrium relations in a period and among several periods. Furthermore, a constant current control strategy by regulating the system input voltage with Buck converter is presented. Combining the relations among system input voltage, the envelope of resonant current and the input of Buck converter, the constant current control law is proposed. The control law is verified with experiments. For the proposed method, in parameter identification, only the data of zero crossing point of resonant voltage and current are required, which reduces the complexity and costs of sampling system. Also, the constant current control law does not need complex computation and is easy to implement.     

The on-Line Identifying Method for the Dynamic Unbalance of the Rigid Rotator

The basic principles of the on-line identifying method for the dynamic unbalance of rigid rotators were discussed. The influent coefficient matrix was proposed to calculate the unbalance,and the matrix elements were obtained by adding the trial weight. The identifying accuracy was verified by simulation tests. Finally, discussed the schemes of the software and hardware of the on-line identification.     

枇杷ISSR分子标记的研究进展

枇杷传统标记方法具信息量少、取材部位有限、无法进行早期鉴定、人为因素影响鉴定结果等局限。ISSR技术以其丰富的多态性、较低的实验成本、相对简单的操作、较高的稳定性以及呈共显性等优点,日益受到研究者的青睐。笔者总结了ISSR技术的原理及优缺点,归纳了ISSR技术在枇杷种质鉴定、遗传变异分析,枇杷分类研究,枇杷指纹图谱构建等方面的进展。发现ISSR技术目前在枇杷上的应用较少,研究深度不够。笔者认为今后可通过提高ISSR技术的准确性,延伸ISSR在枇杷上的研究深度和广度,加强ISSR的联合应用,促进研究团队间的合作交流等方面,使ISSR成为枇杷育种研究中不可或缺的分子标记技术。     

A static equilibrium method for tension identification of in-service cable

To identify the tension of in-service cable expediently and accurately, a cable tension identification method based on static testing measures is proposed by taking cable stress stiffening effect and principle of static equilibrium into account. According to the analysis on the process of cable tension identification and the key technique, a new compound clamp type with the soft metal lining is proposed. The rule of the contact distortion evolvement between the clamp and the cable is analyzed by dynamic nonlinear explicit analysis method, and the law of the friction change following the clamping force is studied. Thus, the reasonability and feasibility of this method is theoretically illuminated. The identified tension only depends on the displacement of load application point and the load force. The proposed method avoids the drawback of normal cable measuring methods where the measuring accuracy is greatly affected by cable boundary conditions and values of material parameters. The tension measured in the method is only related to the displacement of force point and the value of force. Therefore, it provides a new idea for cable tension identification of flexible cable.     

模式识别的斜拉桥损伤诊断动力指纹与识别算法

为有效并准确诊断出斜拉桥损伤,对基于模式识别的斜拉桥损伤诊断方法进行了研究。选取易于测试出的低阶模态频率和部分关键点竖向振型数据为动力指纹,无需模态扩展或模型缩聚。研究并采用全因子设计进行动力指纹库的创建,可精确评估设定的损伤因子及其交互作用对损伤识别结果的影响。设计并增加了带随机误差的动力指纹库样本集。编制了基于Matlab的模式识别的多种算法,重点研究了精确度高的多层感知器识别算法及其提高该算法预测准确率的装袋集成算法。最后给出一座单塔双跨双索面斜拉桥的多种识别算法的损伤诊断过程和结果,得到一种可包容测试随机误差的高精确度斜拉桥损伤诊断评估模型。     

根瘤菌的分类、鉴定及应用技术研究现状

豆科植物(legumines)作为重要的粮食及经济作物,一直以来被广受重视。根瘤菌(Rhizbium)是一类普遍存在于土壤中的革兰氏阴性杆菌,可与豆科植物形成共生固氮体系,不仅可以提高植物的产量而且对周边生态环境无影响。根瘤菌与豆科植物的共生体系是生物固氮效率最高的,占生物固氮总量的65%以上。深入研究这种共生固氮体系对中国农业的可持续发展具有重要意义。近年来,越来越多的学者参与到根瘤菌的分类、鉴定以及应用技术的研究。本文主要从根瘤菌的分类、形态水平、生理生化水平、细胞组分、核酸分子水平的鉴定和根瘤菌的应用等方面进行了综述,为根瘤菌的实际应用提供参考依据。     

小麦双胚苗类型及后代观察初报

对小麦与天蓝偃麦草杂交诱导后代筛选的36个双胚苗株系进行形态特性分类.共有6种,即双鞘同步型.双鞘异步型,单鞘同步型.单鞘一叶重叠同步型.单鞘一叶共生同步型、单鞘异步型,小麦双胚苗二代再现双苗率极小,三代双胚苗两苗系再现频率分别为0.823%和0.139%.二代分离奇异,三代按株系趋向整齐.双胚苗及后代去雄套袋有不同程度的自主结实特性.是有性和无性基因型细胞的嵌合体,双苗特性可通过有性或无性过程传递给后代,无性的表达可能需特定的环境条件.双胚苗是选择兼性或专性无融合生殖的一个中间型桥梁材料.     

利用分子标记快速鉴定甜菜育性的研究

试验旨在优化分子标记鉴定甜菜育性的整个鉴定过程,为分子标记鉴定甜菜育性真正应用于实际育种工作打下基础。以随机抽取的10份糖甜菜和5份甜菜多胚种质资源嫩叶为试材,采用两种甜菜DNA提取方法、双重PCR以及两种电泳方式对甜菜育性进行鉴定。结果表明,裂解液法在提取甜菜DNA上更加高效便捷,1 h就可以提取100份甜菜DNA,效率远远高于CTAB法;采用双重PCR的方式进行甜菜育性鉴定完全可行,使甜菜育性鉴定时间减半。对两种电泳方式进行对比发现,6%聚丙烯酰胺凝胶电泳跑出的结果不能满足实验要求,而1%琼脂糖凝胶电泳跑出的结果完全满足实验要求。通过对用分子标记鉴定甜菜育性的整个鉴定体系进行优化,得出用裂解液法进行甜菜DNA的提取、双重PCR进行甜菜育性的鉴定、电泳方式选用1%琼脂糖凝胶电泳可以达到快速鉴定甜菜育性的目的。