粮虫陷阱检测器与扦样器查虫结果的比较

通过粮虫陷阱检测法与传统的扦样过筛法的对比研究结果,表明粮虫陷阱检测器检测法不仅能及时了解害虫在仓内的种类、数量变化动态,做到及时防治害虫,而且粮虫陷阱检测器检测法具有简便快速等优点,在高大平房仓中可检测出书虱、玉米象、谷蠹、赤拟谷盗、长角谷盗、锈赤扁谷盗、米出尾虫以及蛾类幼虫等害虫。调查的书虱种类数量变化动态以及书虱在仓库粮堆内不同部位分布情况,与传统的电动扦样器过筛法检测结果基本一致。     

Design of Minitype Gas Dynamotor System Based on AVR

This paper introduces the software and hardware designs of minitype gas dynamotor system based on ATMEGA8L singlechip. Step motor is used as the executing equipment in the system. The maximum power of the dynamotor is 5 kW. First, the speed of the dynamotor is sampled, and then the signal is send to the ATMEGA8L singlechip, so as to drive the step motor, thus to control the accelerograph, and to control the frequency of the 9atput voltage, and the main arithmetic is the PID algorithm. The result shows that this technology can be used and extended in producion.     

Speed Estimation Methods Based on Neural Network

In order to solve the speed estimation problems of speed sensorless vector-controlled induction motor drives, the paper presents two speed estimation schemes based on neural network mode identification theory. The advantages of each scheme are discussed and the simulation results show that the estimated speed can trace the actual speed better (even under the circumstances of load variation or speed step variation). Also, these schemes are not sensitive to the variations of motor parameters and the effect of iron loss. Therefore, the proposed neural network based on speed sensorless vector-controlled induction motor drives have good performance in stady-state and transient-state operation.     

simulation of a brushless direct current motor based on finite state machine theory

A novel method simulating a brushless direct current(DC) motor was presented, based on principles of hybrid system modeling and finite state machine theory. Brushless DC motor control mainly focuses on controlling the on/off condition and power switch duration. Modes of control therefore can be defined by corresponding states, and the states can be combined as a finite state machine. This approach uses the popular Simulink/Stateflow simulation method to control brushless DC motor loops. A three phase brushless DC motor was analyzed to illustrate the process of model building with Simulink/Stateflow. The analysis demonstrates the feasibility and validity of the proposed method.     

关于完善中国农村合作经济组织内部运行机制的有关问题探讨

（河南省土壤肥料站,河南郑州450002）     

Creation of an Experimental System for Testing the Dynamic Tensile Stress of Cells Using Membrane Variable Stress Wave

The constitution, design ideas and working principles of the DDC experimental system for testing dynamic tensile stress of outside body cell using membrane variable stress wave are discussed in detail. A new design measure is put forward, i.e. using airtight liquid for transferring pressure, and a space mechanism which is made up of two moveable linking axes and controlled by DDC for producing dynamic tensile stress with variable stress wave. The space mechanism is made up of two moveable linking axes, the first axis is controlled by an alternative current servo system, at the same time it drives the modulating modulating disc, and its rotation velocity is uniform and adjustable, so the rotating velocity of the disc can be controlled. Second, the hydraulic pressure worktable is driven by step electric motor. By dynamically changing the relative position of the modulating disc and the worktable, the journey of the piston in hydraulic pressure vat can be changed accordingly. The resultant motion of the modulating disc rotation and the radial direction relative movement of the piston can create liquid pressure with variable frequency and amplitude range, and the pressure can be changed into membrane tensile stress with variable frequency and pressure amplitude range using pressure fine tuning, and muhi-path disporting pressure. The system is proved to be simple, reliable, economic and controlled expediently by the experiment conducted.     

K近邻的自适应谱聚类快速算法

利用时域递归展开算法对墙体内热湿耦合传递方程进行求解。以木板为例,应用该算法进行了热湿耦合传递的分析计算,在时间域和空间域上分别运用递归展开法和控制容积法进行离散,从而得到递归形式的线性方程组,运用MATLAB软件对这一过程进行求解。计算结果与有限差分算法、解析解计算结果以及实验数据吻合良好,表明该算法能够用于求解多孔介质热湿耦合传递模型。时间步长的改变对计算结果影响较小,可通过增加时间步长方法来减少工作量。     

Method of Exciting in Towards Polarity by Stator-electricity of Synchronous Motor

In order to solve the present problems and enhance the reliability of exitation exist in asynchronous starting of synchronous electrical machine, a method of sensorless best exciting in towards polarity by stator-electricity of synchronous motor is presented on the base of calculated best exciting time through simulation. Detect and analyze the wave of stator current to catch the best exitation time accurately to realize best exitation. The results of experiment demonstrated the advantages of high reliability, short time and low impact when pulling into step, much easier to pull into step in low voltage and heavy load condition. Which showed the feasibility of this method.     

Analysis of shifting control for dry dual clutch system

Aiming at the dry Dual Clutch Transmission (DCT) system, the motor driven dry dual clutch actuator is studied; the characteristic of distortion load for diaphragm spring and the dynamic transient process of the clutch are analyzed. The mathematical model is established for the system using fuzzy control and PI (Proportion Integration) control, and the simulation is carried out for the DCT shifting process. Simulation results indicate that the motor driven dry dual clutch system can meet the need of the shifting process control requirements and guarantee the high performance of DCT system.     

氧化乐果降解菌株发酵培养基碳氮源优化的研究

为确定氧化乐果降解菌株L-3发酵培养基碳源和氮源的最优配比,在质量浓度为1.0mg/mL的氧化乐果降解菌株的基础发酵培养基中,添加不同的碳源和氮源,选出适合菌株生长的最佳碳源和氮源,采用正交试验设计,优化出碳氮源的最佳配比,并进一步测定菌株L-3的生长情况和对氧化乐果的降解效果。结果表明,菌株L-3发酵培养基中最佳的碳源和氮源分别为蔗糖和NH4NO3;最佳的发酵条件为A3B2C3碳源质量浓度0.6g/L,氮源质量浓度0.5g/L,pH值7.0;最适的碳氮质量比为6∶5;菌株L-3在第3天达到生长高峰期,第4天达到降解高峰期,其降解氧化乐果的能力高达86%。优化后的菌种培养基更利于菌体生长,提高了氧化乐果的降解效果。     

Shot Detection System Based on DirectShow

对草莓、胡萝卜复合果蔬汁生产工艺及其成品稳定性进行了研究.采用正交试验设计出的最佳配方:胡萝卜汁与草莓汁重量比1:3,蔗糖添加量10%、柠檬酸0.15%、蜂蜜8%、黄原胶0.10%.该工艺生产的饮料色泽明亮,口感清爽,富含有机酸、氨基酸、维生素和矿物质,具有胡萝卜、草莓双重营养价值与保健功能.     

Discussion on Vertical Bearing Capacity of Rock-socketed Pile

Through analyzing the calculation of vertical bearing capacity of rock-socketed pile given in technical code for building pile foundations, some unreasonable issues in the code were found. At the same time, based on the contacting ways between the pile and the rock and the behaviors of force transfer acted step by step, the unreasonable issues have been proved and the issues to be improved were pointed out in this paper.     

A Method of Simulation of Squirrel-cage Motors with Rotor-rar and End-ring Faults

In this paper,a method used to simulate the squirrel-cage motors with rotor-barand end-ring faults is presented. In our analysis,the stator is still represented by three-phase windings,but each loop of the rotor is considered as a single-phase winding,so it is convenient to describethe situation of the motor with any number of broken rotor-bar and end-ring.Compared with othermethods,the method of this paper can be used to analyse both the steady-stats and the transient stateof cage motor with rotor faults.     

Analysis of LLCC resonant driving circuit for ultrasonic motor

The dynamic characteristic of USM(ultrasonic motor) will be changed greatly when USM rotates and is greatly influenced by the variation in the quality of the motor, while the LLCC driving circuit can generate a geometric frequency which can make the LLCC     

Selecting Enterprises for Swap of Debt to Equity and Mechanism Design

The swap of debt to equity in state owned enterprises is dynamic game processes of conflicting and struggling among the concerned parties for the maximization of its payoffs and the seeking of domination for financial resources, and can be accomplished successfully when its being brought into effect is going to be propitious to the concerned parties. This paper analyzes the problem of selecting enterprises for swap of debt to equity under the frame of information economics theory, and argues that the selection of enterprises for swap of debt to equity is a problem of mechanism design. As the expected utility function of enterprises is analyzed and Asset Management Corporations adopts a series of measures to deal with it according to analysis, a policy frame will have been constructed.     

A new determination method of tool step for 5 axis NC machining

The peculiar non linear error in the 5 axis NC machining is studied. An improved tool step determination method for the 5 axis NC machining is proposed, in which the non linear error is compensated. Both the arc chord error and the non linear error are considered when computing the tool step, and the comprehensive error is taken as the function of the tool path parameter. Due to the difficulty of gaining the derivative of this function and the tool step according to the prescribed tolerance, the secant method is improved to guarantee the real solution locating in the converging range which is adopted to compute the tool step. The implementing example shows that the proposed method can compensate the non linear error effectively with meeting the prescribed tolerance. The exact tool step can be gotten efficiently with the improved secant method.     

农业科技成果转化存在的问题分析（I）

在以往研究我国农业科技成果转化现状的基础上,研究了农业科技成果转化率低的主要原因是：现有农技推广部门的运行机制与市场经济不相适应;农业科技成果与生产实际脱节;推广人员的知识结构不合理;农业教育、科研、推广三者之间缺乏良好的合作机制以及科研成果转化自身的障碍因素等问题。以便采取相应的对策措施。     

水稻稻瘟病防治方法研究进展

稻瘟病是水稻三大病害之一,生产上对稻瘟病的防治没有特效的方法。为了对未来水稻稻瘟病在生产实际应用上提供一些参考,分别从化学防治、抗性品种培育、生物防治、栽培管理方法等方面概述了水稻稻瘟病防治方法相关研究进展。分析了化学防治、抗性品种、生物防治、栽培管理在生产应用上的利弊,指出了抗性品种选育、合理栽培管理技术和高活性生物农药三者综合利用将是防治水稻稻瘟病有效的措施。     

河北新农村民居的有机更新设计实践

在对传统民居建设现状反思的基础上,以迁西县青山口村设计实践为例,通过构建新农村民居有机更新理念,从新民居的特色保持,户型更新,功能完善,可持续发展各方面逐层深入提出可行的措施,从而促进新农村社会、经济、生态的可持续发展。     

食品污染的危害及其防治措施

食品污染是影响食品安全的主要问题。按污染物的性质,食品污染可分为生物性污染、化学性污染和放射性污染。通过对食品污染的来源进行分析,指出了食品污染的危害和防治食品污染的措施与建议。