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Aiming at the influence of temperature on the rate of chicken’s hatchability in hatch field, this paper uses a flexible wireless VISA communication technology based on LabVIEW to measure and control the temperature in process of chicken hatching. The hardware part was composed of microcontroller C8051F530, digital temperature sensor DS18B20, wireless data transmission module nRF and display module HB240128 for real-time acquisition and processing of temperature data. The software part was written by graphical programming software LabVIEW, and used it to design system interface for functions of real-time processing of temperature data, waveform display, threshold alarm etc. The system can be implemented by hardware circuit itself and computer system interface for the temperature control, which enhanced flexibility of the system and was conducive to troubleshoot interference problems. The test results show that the temperature measurement system was characterized by simple operation, easy maintenance, steady performance and high accuracy.

In view of the digital geophone self-test system application demand for a variety of high quality waveform signal. This paper introduces a kind of design method of direct digital synthesis waveform signal generator based on FPGA. It mainly discusses the principle of the method of frequency synthesis technology, design thinking and implementation method. And using the design method of pipeline structure to improve circuit structure of 48 bits phase accumulator, so as to improve the running speed, and further increase the resolution of frequency synthesis. The test shows that the signal generator can produce sine wave, square wave, sawtooth wave, triangle wave. The frequency resolution can reach 0.18μHz. The highest output frequency is up to 20MHz, and frequency switch time is 20ns.

In this investigation, nanoSchiff bases Cobaltic complex was synthesized and used as the initiator in the copolymerization of carbon oxide and propylene oxide (PO). The nanoCobaltic complex was characterized by infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). The influences of different factors, including reaction time, reaction temperature, and pressure of CO2 on the synthesis of polycarbonate were described. The results show that nanoCobaltic complex could be successfully applied in the copolymerization of CO2 and PO. The optimum conditions of the polymerization, which include CO2 pressure of 30 bar, reaction temperature of 80 °C, and reaction time of 3 hours.

In this article, a design method of asynchronous FIFO memory based on FPGA is put forward. With FPGA as the core controller, We adopt Verilog HDL and top-down design method to build a top-level module design and also analyze the mark logic of asynchronous FIFO and the elimination of semi-stable state under Quartus II development platform. Besides, with the application of Gray code conversion technology, not only the reliable transmission of data is guaranteed but also design efficiency is improved. Through contrast experiment analysis and simulation test, the validity and reliability of asynchronous FIFO memory are verified, meeting the basic requirement that FIFO can hold more enough data without spillovers despite the fullness of data.

In this article, a design of multi-channel data acquisition system is presented. With FPGA as the core controller, the system can implement logic control over the high-speed ADC and acquire high-speed and high-resolution sample data. Using asynchronous FIFO as a cache, it can transfer data between two different clock domains: ADC data acquisition module and RS485 data module, which helps to improve the work efficiency and data throughput of the system. In the Quartus II development platform, Verilog hardware description language is adopted and finite state machine so that parallel acquisition operation to multi-channel ADC controlled by FPGA can be achieved and the system can become equipped with high-resolution, strong real-timeliness, low noise interference and other advantages. When it comes to the final step, simulation of AD sampling, asynchronous FIFO and RS485 transmission are conducted under the Modelsim environment and on-line testing by Signaltap to the system is synchronously implemented. The validity and reliability of the system are verified.

Using SEMI standards to provide the communication interface and communication information between the semiconductor device and the factory host, in order to improve the yield and quality of semiconductor products has been a general consensus. In this paper, through the analysis of the related standard about the material transport in SEMI, and the specific introduction of the actual device model of the semiconductor equipment, describes the process of material transportation factory automation technology and the application in the actual equipment.

This work presented the design and implementation of a wireless acquisition system for seismic signal. 4 distributed signal acquisition stations were integrated to the low-power prototype which composed of 48 acquisition channels, and a star-shaped wireless network was built which is suitable for seismic data transmission using the networking mode of multi-pipe and multi-address switching. A distributed seismic data acquisition system was accomplished which has the function of synchronous control and asynchronous transmission. The key technical problems and solutions of time balance distribution between multi-channel time-sharing switching acquisition and temporary storage, and wireless seismic data transmission is analyzed in detail in this paper. Thus the additional accessories of traditional wired seismograph were greatly reduced, to improve its cable layout trouble and low efficiency of construction in an adverse environment. This system increased efficiency more than 50% and took same exploration effect compared with wired mode in the field application.

In this paper a cellular automata model is proposed to describe driver behavior at a single-lane roundabout. Two truncated Gaussian distributions are used to model heterogeneous and inconsistent driver behavior. Numerical results show that our method is feasible and valid.

It has been proved through the extensive study of continuous Form/Fill/Seal packaging machine that the outlook and final quality of the formed bags are largely dependent on the accurate synchronisation of vertical and horizontal sealing subsystems. In this paper, we first investigate synchronisation problem existed in the sealing system of traditional continuous F/F/S packaging machine which is mainly due to the mechanical non-constant transmission system used in the current continuous F/F/S packaging machine. A new control scheme is then proposed to address this problem in which the driving of the horizontal and vertical sealing has been made into independent but connected subsystems and controlled by separate control modules. We discuss the mathematical model and physical design in which the mechanical transmission part is discarded therefore simplifies the whole design of the machine. The new control scheme has been testified in several industrial applications with excellent performance result.