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Embarking on the need of agriculture yield estimation and yield capacity, and the need of wheat threshing in agricultural colleges and research institutes, this text gives the design of miniature Direct-Current (DC) electric threshing machine using storage battery as power source based on the characteristics of the DC which is easy for storage. At the same time , the threshing machine is driven by a DC motor, considering the field threshing of the yield capacity and the yield estimation and the reality needs of small sample nicety threshing. The device has the advantages of light weight, small volume, simple operation, easy maintenance, convenient carrying.

Algorithm of vehicle scheduling optimization could be integrated in the GIS platform. Therefore, distribution software can automatically make the delivery plan and managers also can make the optimizing choice of the optimal distribution route. Firstly, this paper introduces the necessity of introducing GIS into the logistics industry. Moreover, advantages and disadvantages of the current path planning in the logistics distribution which often used in some algorithms (genetic algorithm, mountain climbing algorithm, ant colony algorithm, etc.) will be listed. Finally, a more practical hybrid algorithm will be used to the GIS so that managers can optimize the logistics distribution path selection.

Basing on the basic attributes of the green machine product, the article put forward the main principles that should to be abided, when construct the synthesis evaluate index system. Then use the AHP method in analyzing the choice approach of the green machine product`s design scheme. Green machine product means that in its whole life process (including material gaining, designing, manufacturing, packing, transiting, using, recycle, reusing or refilling), we can economize the energy, do little or minimum damage to the environment, protect the worker well. It has four characteristics including technology advancement, economic, resource saving and environment friendliness. Green machine product design is to make sure that it can influence the environment less and keep its basic functions, service life and quality. Its green degree play an important role in judging whether or not it can meet the green product’s basic requirements and improving its design project and produce technology.

Based on the friction stir welding rig,the temperature field model was established by COMSOL Multiphysics under the coupling effect of joule-heat and friction heat. The coupled temperature field distribution and variation rule of the analysis model were simulated and analyzed under current-carrying or without current. The results show that the maximum temperature mainly distributes the contact area of the pin tool and work piece. The distribution of the temperature and isothermal layer with current is basically same with non current. The temperature distribution area of shoulder with current gets larger than without current condition. Under the constant welding velocity,axial force,rotation velocity and displacement,the maximum temperature produced by coupling function of joule-heat and friction heat is much higher than the one,which engendered by friction heat.

This paper studies the impact of network time-lag on the spread of worms and virus, uses Lotka-Volterra equation theory with time delay, and studies the influence of network characteristics such as response time, predator copy size and interaction of network worms and predators.

To resolve the problem of data transmitting in multi-sensor network possessing of a lot of sensors and processing sensors signals on the same time base and transmitting the results remotely, a three classes’ bus topology structure based on intelligent node was designed. The system comprised scene devices, transmission cable, and console. The scene devices included several gateways, more nodes and sensor groups. The console communicated remotely with gateways via Ethernet, and gateway communicated with nodes via CAN bus, each node managed a group of sensors via RS-485 bus. The designs of intelligent node were presented in detail including hardware design, transport protocols, as well as program flow. Above conceptual design was applied successfully in a certain multi-sensor network system principle prototype consisting of a console, a gateway and three nodes possessing of ten sensors. The results prove the conceptual design feasible.

In order to meet the needs of speed measurement for rotation system, a rotation sensor which based on the principle of Anisotropic Magnetoresistive Effect was designed in this paper. This paper presents the principle, detailed hardware circuit, frequency characteristics of the sensor, as well as the valid detection distance. The sensor used MR elements as the sensing element. It turned the change of the magnetic gear’s rotation speed into the change of the circuit’s output signal and ultimately achieved contactless rotation measurement of the magnetic gear. The hardware circuit of the sensor includes five parts: signal collection, impedance matching, signal amplification, digitalization processing and signal output. The tests show that its operating frequency ranges from 2 Hz to 6 KHz.

For the reasonable grouping of the 16 vessel traffic flow observation lines along Yangtze River to compare them with each other, essential data of nearly 6 years taken with the mean relative growth rate of traffic flow over the yearly same period set as clustering index, the clustering of the 16 vessel traffic flow observation lines was realized on MATLAB in accordance with the set index based on the basic principle and processes of Agglomerative Hierarchical Clustering Method, which indicated that the observation lines can be divided into 3 classes, and particularly Jiujiang took an exclusive class obviously different from the other two. This work would provide scientific basis of grouping the observation lines in order to reflect shipping economy of the regions where the observation lines are located and to provide reference for management decisions.

During the production of the low-pressure casting aluminumwheel hub, the head face deformation and axial deformation of the casting blank are always happened due to various factors.The casting wheels beyond tolerance are considered as waste products with no need for further machining. Traditionally, the measurement of the deformation is usually static and by handwork,which limits the accuracy and reliability. This paper introduces anon-line automatic measuring system for casting wheels based on laser measuring technology. The configuration of the system and measuring method are presented in detail. Test results showed that the system could meet the measurement requirements: the whole measurement process operated quickly with the total time of 30s; the dimensional accuracy reached 0.02mm while the measurement error of the deformation was within 0.04mm. The system achieves better repeatability and reliability compared to the manual measurement.