Abstract:An ER shock absorber with mixed mode is designed and its mathematical model is built. The optimal control method with LQ is applied to semi-active suspension systems in vehicle. A optimal output tuner is designed on basis of 1/4 dynamic model and the characteristics of the ER shock absorber. Its aim function and the weighting parameter matrix are determined. The feedback gain vector is found from solving the Algebraic Equation. The result shows that the optimal controller could not only diminish the body acceleration effectively but also improve the ride and handling characteristics. The construction of the ER shock absorber is reasonable and its performance meets the optimal control requirements of semi-active suspension system under the 3 kV/mm. In additional, the optimal control has low cost and energy consumption as well as rapid response . Such a system can meet with the requirements of semi-active suspension control completely.

Abstract:A strategy for induction motor control based on the grade of errors is developed to improve the performance of hybrid vehicle drive system. The stator flux error, electric magnetic torque error and flux position angle are used as control variables, and rules for the switching states are chosen according to the errors and the principle of the Direct Torquc Control. This strategy improves efficiently the electric magnetic torque response of the system. The result of simulation shows that this strategy is an ideal control strategy of hybrid vehicle, which can make the motor generate the electric magnetic torque efficiently, steadily and quickly.

Abstract:Based-on the new 8-bit microcontroller P89C51RD2 of PHILIPS company,the principal axis rotating speed of friction welding machine is controlled in closed loop by the system. That guarantee the stability of important parameter in friction welding.The design of software and hardware and the principle of the system is introduced detailedly.The output pulse of photo- coder is measured by using catching mode of P89C51RD2' PCA.And the D/A conversion is achieved by PWM pulse wide modulate mode of P89C51RD2' PCA also. With ISP function, the system program can be written or upgraded on-line and with long-distance.The whole circuit formed in module is very concision.The system runs well in practical production.

Abstract:It is analyse and calculation about the dynamic characteristic of motorcycle frame by FEM model,carry on validation through experimental modal method,Get back frame modal parameter and shake type.On the base of analyse,ameliorate the structure of motorcycle frame,and validate the effect of amelioration, elevation the comfortable porperty of riding motorcycle. Therefore, it has important theoretic significance.

Abstract:Based on the possible factors on limiting the maximum deep-drawing height of the cylindrical cup, the fuzzy set theory is applied in optimizing the deep-drawing process design and the simulation software of metal deformation is utilized for the test of optimized design. The result of the test directs the core design of CAPP for the deep-drawing of the cylindrical cup and improves the CAPP programe's flexibility as well as practicability.

Abstract:The traditional E-R's model can abstract the real world strongly, but the relationship among entities in E-R's model is very mixed and disorderly .In order to improve the productivity of the module of data input,the layered E-R model based input technology is presented. The logic model( relational model) produced by the traditional E-R model is layered by primary keys. According to the layered model ,the input interface is produced .First the input interface of 1th-tier entity is produced .By using the input interface of 1th-tier entity ,the input interface of 2rd-tier entity is produced ,until the input interface of the last tier is produced.

Abstract:Road detection is a sub-system of vehicle intelligent auxiliary drive system, which includes such sub-projects as road segmentation and road recognition. The image from CCD camera is processed, and road line is abstracted from it through image process. Then the direction of the road, such as left or right, can be identified according to the road line. Because of the special requirement, i.e. the rigid real-time requirement, the algorithm adopted must have the very low time cost. Through many experiments, a kind of recognition algorithm is proposed based on region-growing process and curve fitting, which was verified to have good effect.

Abstract:In order to improve the existing method of electric network reliability evaluation, the basic concepts, for example, the flow through the failure events, the sent ends and received ends of these failure events, the load curtailment region of the received ends and the degree of the load curtailment, are defined. With these concepts, the connotation of LCSN (Load Curtail Strategy by Near) is enriched and algorithms of the load curtailment region are conducted. The theory foundation for further exploring LCSN is created. The results show that the algorithm can quickly and effectively make reliability assessment of power systems.

Abstract:From the viewpoint of nonlinear dynamics, this review outlines the recent advances as well as some open problems in the study of neural networks with time delays, an important class of delayed systems in various neural network models. The survey includes three aspects as fellows: the dynamic features, available approaches and advances in research on most attractive problems. The evolution of a delayed neural network depends not only on the current state of the systems but also on previous ones. Hence, a delayed neural network should be modeled by a functional differential equation, the solution space of which is of infinite dimensions. Therefore, the dynamical behavior of delayed neural networks is very complex.

Abstract:The paper deals with the statistical characterization of mobile satellite channel, and introduces a statistical channel model-the Shadowing Rician Fading model for frequency nonselective land mobile satellite channel. The parameters contained in the model are given by means of trial and error. Based on the model, the BER(Bit Error Ratio)performance is analyzed for narrow-band modulation and wide-band spread -spectrum modulation of coherent PSK (Phase Shift Keying) signals. The results show that the multipath and fading phenomenon in the channels worsens the system bit error performance, while the use of wide band spread spectrum modulation can improve it efficiently. In addition, an analytical expression is derived for the irreducible probability of bit error of coherent PSK signals due to phase variations caused by fading and shadowing. At last, the numerical results are obtained and discussed.

Abstract: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 .

Abstract:The web documents classification is an important research content of web mining. Document vector space model is the foundation of automatic classification of documents, while it is difficult to eliminate redundant attributes and reduce the dimension of the vector space. The Rough Sets Theory is applied to generalize the information system comprised by document samples set, and to compute the best reducing properties set. So dimension of document feature space is reduced greatly, and disturbance to document classification is decreased too, which improve the efficiency of classification. In addition, using the advantage of adaptive classification and incremental learning of Fuzzy ARTMAP neural network, the online adaptive classification of web document is achieved.

Abstract:Based on the object-oriented method,according to the Enterprise model of Information Integrating,by means of the idea of Encapsulation and Inheritance,a common reference framework for Information Integrating of CIMS is presented. This kind of integration is not only used for the share information,but also ready for Function Integrating and the whole construction of CIMS. Moreover,the system developed based on this model can be reused for many times. The developing circle of CIMS can be apparently shortened,too.

Abstract:Parallel Halley iteration method, based on circular arithmetic for finding all zeros of a polynomial, avoids troublesome circular extraction operation,and the approximation with error estimation of all zeros of a polynomial can be obtained at the same time with it, and it has higher convergence rate , while it was synchronous parallel algorithm. The asynchronous parallel algorithm was constructed with circular arithmetic in order to find all zeros of a polynomial, and the convergence theory was established under the similar condition of Halley iteration method. The algorithm not only retain the advantage of Halley iteration method, but has better parallelism.

Abstract:Owing to unique structure and characteristic of carbon nanotubes, much more are attracted attentions since they were discovered .In recent years, carbon nanotubes have been successfully synthesized by various methods. Especially, highly aligned carbon nanotubes were grown by chemical vapor deposition (CVD). In the work, it is studied that different thickness of catalyst affects the diameters of carbon nanotubes. Carbon nanotubes were grown on silicon substrate coated with different thick NiFe films by bias-enhanced hot filament chemical vapor deposition and their growth was investigated by scanning electron microscopy,Onset of analyzing of deformation of different thick catalyst films during heating the filament. The results indicate that catalyst particles encapsulate the top ends of carbon nanotubes, and that the catalyst thickness greatly affects the diameters of carbon nanotubes, which increas with increment of the thickness of NiFe films.

Abstract:Based on the distance between atoms and firstly electronegativity of each atom, a new set of descriptors called molecular electronegativity edge-distance vector (VMED) applied to describe molecular structure of E.coli transcriptional DNA-promoter sequences, is firstly proposed , because it is easy to calculate, only from primary structure of DNAs. Here a new type of quantitative structure-activity relationships (QSARs) called quantitative sequence-property models (QSAM) is developed with good forecasting ability by multiple linear regression (MLR) method. The results show that VMED has both excellent structural selectivity and good activity estimation. Besides, this novel vector will be useful to structure characterization and activity prediction of biological molecules. The resulting structural descriptors can be used to investigate requirments for new nucleic acids(NAS) in order to obtain sequences with altered activities.

Abstract:Based on the reactive surplus of Chongqing 220 kV main electric power network under low water and low load, and on state of higher system voltage, a thorough research is done on voltage and reactive power of the system power network by means of calculation,analysis and experiments. A main network calculating equivalence model of power network in Chongqing is constructed. And reactive power optimizing calculation is figured out on the Chongqing power network on condition that the loss minimum of the active power network is object function. Several optimizing compensatory schemes are put forward. Based on the calculation result and the analysis of all schemes, the most reasonable and feasible optimizing scheme could be achieved. Meanwhile, the feasibility that the system voltage could be adjusted when generator operating under excitation was demonstrated. According to the experience of under-excitation operation of the same type units , it decreases the system voltage, improves Chongqing power network running performance, and strengthens the coordination and stabilization of system.

Abstract:Using double-circuit transmission line is the developing tide for main 500 kV configuration to reduce line holding ground, so analyzing it's lightning protection performance is important to extend double-circuit transmission line in ultra high voltage network. The lightning protection performance of 500 kV double-circuit transmission line is studied with EMTP and EGM. The statistical method is applied to analyzing the lightning protection performance of back stroke by considering the randomness of working voltage's phase when lightning stroked the top tower. The result is that the line lightning protection level is different when the working voltage of conductor is different. It also improved the EGM by considering the effect of wind speed when analyzing the lightning protection performance of shielding failure. Furthermore, the results are given that wind speed has effects on the protection angle and the rate of shielding failure by using the program to calculate it.

Abstract:With the development and complication of power system, the problem of low frequency oscillation in electric network becomes obvious. Unified Power Flow Controller is one of the most powerful facilities in Flexible AC Transmission Systems, which can improve the transient stability and damp the low oscillation in power system with suitable control. Considering the characteristics of inverter's output voltage magnitude, adjustment of phase and process of charge and discharge of dc capacitance, the dynamic model of UPFC is proposed by a series of nonlinear differential coefficient equations. Based on UPFC's dynamic model, the linear optimal controller of UPFC with state feedback is proposed. In this way, the low frequency oscillation is damped effectively. A simulation is processed basing the theory.

Abstract:Compared to bi-fuel engine,it uses completely CNG(Compressed nature gas) to replace diesel which can save more oil fuel than bi-fuel engine that reffited diesel engine into CNG engine. A 4102 diesel engine is refitted into CNG engine and a mechanical ignition timing system is designed by the method of gear and belt. The principles and the construction of the system is introduced and the characteristics of the design is analyzed. The system performed well and had good liability when run in a platform. Compared with the previous one, it kept higher dynamic character and emitted lower. It is a cheap one and can be use to reform the diesel engines.

Abstract:Low temperature is one of abiotic stresses limiting the geographical location suitable for growing corps and periodically account for significant losses in plant productivity, so it's important for agriculture to improve the cold resistance of corps. Many plants can acquire increased frost tolerance after a period of exposure to low, non-freezing temperature through a complex adaptive process called cold acclimation. In the past ten years, with the great advance in the researches of molecular mechanism of cold acclimation, the studies of genetic engineering for cold resistance in plants have also been carried out extensively. Currently, there are two kinds of genes used in plant cold-resistant genetic engineering, Which are protective genes and regulating genes. Many studies indicate both kinds of genes have good prospect for improving the cold resistance of plants. However, there are also many problems in this field to be solved immediately.

Abstract:The acquisition of physiological signals is the first step of its analysis and processing. The development mode for PC/104 module is introduced and the design of multichannel acquisition system for physiological signals based on PC/104 is also put forward. The system hardware mainly includes PC/104 embedded computer,DIAMOND-MM-16-AT acquisition card and four-channel amplifiers. Windows 2000 is used as operating system for PC/104 embedded computer. The multithread program to sample data is made by means of programming language Visual C++ 6.0. The experimental results show that the system can be applied to sample, analyse, and process the physiological signals. The system also has lots of advantages, such as small volume, low power, firm structure and steady performance.

Abstract:以不同浓度的3种激素(GA3、NAA、6—BA)处理基础发芽率约为20％和60％的水稻陈种子，研究其对陈年水稻种子发芽势和发芽率的影响。结果发现，GA，对2种水稻陈种子的发芽势和发芽率影响微弱，NAA极显著的降低了2种水稻陈种子的发芽势和发芽率，6—BA处理后前者种子发芽率显著下降，后者种子发芽势极显著下降。

Abstract:对Ф2 5mm和Ф32mm两种规格 2 0MnSiVHRB4 0 0钢筋的高应变低周疲劳性能进行了研究。采用控制总应变幅不变试验 ,测定了 2 0MnSiVHRB4 0 0钢筋高应变低周疲劳过程中的循环应力响应特征、循环应力与应变的关系。用Basquin公式和Manson-Coffin公式拟合得到了两种规格钢筋的疲劳寿命计算公式 ,据此计算了Nf=10 0时的σa·Δεt值 ,发现试验钢筋的高应变低周疲劳性能较 2 0MnSiⅡ级钢筋有了较大的提高。断口扫描发现 ,由于第二相质点和夹杂物的存在 ,形成微孔洞和微裂纹 ,裂纹之间因内颈收缩 ,互相连接形成疲劳断裂

Abstract:Titanium has many desirable properties (high specific strength and high corrosion-resistance). Titanium metal is a sort of product with promising market. Hunter process disappeared completely in 1993. The most widespread titanium sponge process is Kroll process (magnesium reduction). Its shortcomings (complicated route, high cost and serious pollution) are obvious although it is the most mature technology. The most advanced came up in UK, 1998. It is characterized by low cost, excellent product, short route and extensive adaptability, and is a type of high cleanness process. Compared with other processes, this electrolyzing process for the direct reduction of TiO 2 represents the tendency of titanium metal making in the future, and should be applicable to a wide range of metal oxides.

Abstract:The most concerned issue nowadays for the refrigeration circles is to find out a certain refrigerant that could tolerate with nature, also have excellent performance and is liable to obtain as well. In the light of safety of natural refrigerants, we set up an experimental apparatus for flammability limits and analyze the experimental principle. The reasons that may influence the value of the limits are given. The experimental investigation of the flammability limits of Propane, Isobutane and Methylamine is carried out. It is shown that, if the consistency of the refrigerants in air increases approximately to the flammability limits, high-energetic ignition source is also needed to explode. However, it is necessary to take some precautions for safety.

Abstract:The pathways of organotin compounds entering the environment, mechanisms of tin methylation, bioaccumulation, transport and degradation of organotin compounds in the environment are summarized, and the toxicity and anticancer activity and ecological effects of organotin compounds are also discussed. Organotin compounds were applied in the industrial, the agricultural and antipollution dope for the shipping, with transport into water body. Microbes play an important role during tin methylation. Organotin compounds were decomposed by the water, the photo and microbe. TBT and TPT are very toxicity to halobios, and can be condensed by them, enrichment index is between 5 000 to 10 000, which strongly affect the ocean ecosystem. Development of environment-friendly dope for shipping, and studying organotin effect on halobios community and ocean ecosystem are suggested.

Abstract:The rock property difference of bedded composite rock often does not lead to ideal Pre-splitting blasting effect. The influence factor of Pre-splitting such as the dynamite quantity and explosive structure was studied by experiment with transient dynamic strain gauge testing system. At the same time, the damaged rock reduced by blasting was examined with RS-STOIC ultrasonic gauge. The results indicate that different dynamite densities are taken for considering especially property of bedded composite rock. The conclusion for cite.

Abstract:In order to analyze the stability of the landslide, it is important to make the shear strength test to discontinuity of the landslide. So, we must use a method of simpleness, practicality and speediness to determine the shear strength of the discontinuity. Using homemade shear equipment, the authors make shear strength test to model from landslide of ZHAIBA under different situation. After analyzing the experiment data we conclude that the shear strength of the discontinuity is relevant not only to compressive force but also to containing water of the discontinuity, Shear strength will rise as compression force rise and will reduce as containing water of the discontinuity rise.

Abstract:Rockburst is a serious damage geologic hazard. According to the rockburst phenomenon in Erlangshan tunnel and the Jinping 2nd hydropower station and a large of rockburst data,this paper proposes that rockburst is a result that many factors synthesize. These factors include teconics ,epigenetic and superficial structure, wall-rock intensity, attitude of rocks, wall-rock state of stress, wall-rock deformation and underground engineering arrangement, etc. It is given that the mechanism of rockburst is a tension fracture damage under press.

Abstract:The second-generation control system of scanning motion of industrial computerized tomography(ICT) systems is that the scanning motion is divided into translation and rotation. This paper only focuses on rotation. After acquiring the transferred function of the rotation based on the features of the system, we simulate the system to get the parameters of the motion in the field of time and frequency with Matlab, and modify it to some extent in order to change its capability of response for getting the best control.

Abstract:目前国内的数据库应用系统，多数是在Client／Server模式主流商用数据库产品环境下进行开发和运行，其安全级别较低。由于不可能对商用数据库产品进行修改，从应用实际出发，提出由数据库安全代理增强数据库应用系统的安全性。在分析数据库应用系统特点和安全需求基础上，结合实际系统研究了数据库安全代理的功能和在MIDAS技术基础上的设计和实现，并对其抵御常见数据库攻击手段的能力进行了分析和实验。

Abstract:In the course of Information Engineering of enterprises, because of the existence of unplanned system and information verification, enterprises have to change primary data model of the information system. But existing information organizing technique and theory can not solve the influence that unplanned system and information verification impact on preserve linkage and preserve dependency of the data model, and this has great effect on the process of Information Engineering. Aiming at solving the problem mentioned above, on the basis of Relation Data Theory and making use of E-R model, the paper puts forward an information organization technique based on entity linkage with well expandability and flexibility. The technique can adapt to information verification and adjustment of enterprise.

Abstract:This paper points out that the price, quality, the level of supplying on time, the level of after-sales service and so on can be regarded as resources that the suppliers can provide, and proposes a concept called the comprehensive level of resources exploitation which can be used to evaluate the comprehensive effect of order quantities allocation of one product between several suppliers. A relative index is presented to measure the comprehensive level of resources exploitation. The index is fit for comparison between several order quantities allocation plans in different time to evaluate which plan exploits the resources of suppliers more effectively. Finally, this paper establishes a linear programming model to solve the optimal order quantities allocation based on the highest comprehensive level of resources exploitation.

Abstract:The investment behavior distortion of myopic agent with asymmetry information has remained unsolved,the BS characterization of the inefficiency from managerial myopic hinges on a restrictive informational assumption and therefore is not generally applicable. Paul demonstrates that it is not necessarily true that hidden-action type leads to under-investment in long-run projects. We examine the hidden-information type and arrive on analysis:in general,over-investment in the long-run project can be ensured only if the manager has more information than the stock market about the long-run project,but not about the short-run project.

Abstract:The distribution of the five-day's return on China composite stock index is studied. The empirical distribution of five day's return on SHCSPI(ShangHai composite stock price index) and SZCSPI(ShengZhen composite stock price index) has "fat tail" and no finite variance with sharp peak at mean ,which can not be normally distributed because the largest negative return possible. In addition, the return series are belong to long-turn memory fractional time series. China stock markets are not efficient markets because the chaos phenomenon is strongly shown in the stock market.

Abstract:Through an analysis on specialization and synthesis development of Chongqing's three-D industrial structure and 13 major sectors, dominant specialization sectors and their status and functions, the relationships among dominant specialization sectors and non - specialization ones are given in this paper. This would be helpful for Chongqing to establish rational industrial policies, to upgrade its industrial structure level.

Abstract:The situation and the future of the automotive industry information construction is shown in this paper. The significance of Chinese automotive industry information construction is discussed,and the technology base and system structure is also described. The function and the structure of information system by one application of marketing plotting system in one automobile factory's E-commerce are introduced.The important significance for develop and research of product and strategic decision is shown by building market demand information system.

Abstract:According to tribochemical reaction and modeling of action mechanism ,the action mechanism optimized by nanoparticles in oil lubricating under friction is studied .The surface of a couple material is optimized by the together action of three approach stated as follows: Firstly, the thickness and intensity of lubricating layers or films provided with the action improving tribological properties increase because of enrichment of nanoparticles on the surface or near surface of couple-material arising from short force. Secondly, new lubricating film is built because of tribochemical reaction concerned with nanoparticles enriched in surface under friction and wear. Thirdly, the surface of couple-material is optimized by nanoparticles, for instance machine polishing, filling and leveling up the tiny hole and crackle on surface.

Abstract:2002年，《重庆大学学报(自然科学版)》改版，从双月刊变更为月刊，为考查改版的效果，用学术期刊综合计量方法，对该刊2001年和2002年的载文量，选题单位，论文合著度，第一作者的年龄、职称、籍贯的分布情况和科学基金资助项目的刊登情况等期刊基本参数作了对比分析，结果表明：改版后，论文的刊出量明显增加，发稿范围和在支持学校学科建设上的效果是突出的，第一作者的年龄、职称情况趋于合理，为学校青年骨干科研人才的尽快成长起到了支撑作用，但在科学基金资助项目论文的发表比例上有下降趋势，并就此提出了相关建议。