工厂化水产养殖智能监控系统设计

提出了一种工厂化水产养殖中具有可溯源功能的智能监控系统.系统利用PROFIBUS-DP总线和工业以太网技术实现了数据的传输与共享,利用模糊控制与神经网络相结合的算法实现了对数据的处理分析,并得到控制信号,进行闭环控制,利用无线射频识别技术( RFID)实现了水产品质量的可溯源功能.结果表明,养殖环境各关键环境因子均满足控制精度,水产品的可溯源信息写入与读出均完整有效,完全达到了设计要求,能够满足工厂化水产养殖智能化的需要.     

射频识别技术在粮食供应链体系中的应用研究

将射频识别技术应用于粮食供应链系统中,力求实现供应链体系运行的快速与高效.介绍了射频识别技术的基本原理及特点,在此基础上构建了粮食供应链管理系统的系统模型,并给出了粮食供应链管理系统的系统架构,以及基于射频识别技术的实现过程,最后对现存的问题和相应对策进行了概述.     

The Biological Effects of Low Frequency Electromagnetic Fields on Cells

The biological effects of ELFMES including proliferation and apoptosis of cells as well as the damage of DNA are initially evaluated with the treatment of plant cells and human pulmonary fibroblasts in low frequency magnetic fields with certain intensity and different time intervals in vitro. Cell culture, counting in vitro, fluorescent dyeing analysis and single cell gel electrophoresis are adopted. The results demonstrate that the electromagnetic field with the intensity of 3mT can affect the proliferation and apoptosis of cells significantly.     

The Effect of Additions in the Fermented Solution on Bubble Coalescence

This paper presents a detail study of bubble coalescence in inorganic salts and organic compounds of fermented solution ,and preliminary analyses the principle of bubble coalescence.The experiments show that the relationship between the solute concentration and coalescence frequency reveals the existence of sharp transition concentration.     

A PRACTICAL PWM CONTROL METHOD OF CURRENT SOURCE GTR INVERTER

According to the principle that the orbit of stator current vector in complerplane should be as close to a circle as possible, the PWM control pattern is derived and determined. The control method is realized by using a micro-computer.     

锌元素对籼稻成熟胚愈伤组织绿苗分化率的影响

本实验就锌元素对籼稻成熟胚愈伤组织绿苗分化率的影响进行了研究，结果指出：(1)锌元素能明显提高籼稻成熟胚愈伤组织绿苗分化频率，且使用浓度范围较广(0.5～10μmol/L)，其中以锌浓度1μmol/L效果较好；(2)在本实验范围内各籼稻品种对锌元素的反应是一致的，但品种间差异很大，其中中早14绿苗分化率较高；(3)锌脉冲试验指     

Simulation Propagation of Partial Discharge UHF Signals in Transformer

Many factors affect the propagation of ultra high frequency(UHF) signals caused by partial discharge(PD) on the waveforms and energy of signals in transformer.To investigate the relationshi Pof factors and UHF signals,simulation model of transformer for PD study are established.UHF signals in simulation model of transformer caused by PD are calculated using finite difference time domain method.By means of amplitude and cumulative energy plot of simulation signals,and combing the measured result,the following factors:distance between PD source and detection position,different metallic conductor position around detection position and iron core and winding are researched,which contribute to comprehend the propagation characteristic of UHF signals and detect UHF signals accurately.     

Frequency Refining Analysis and Its Applications in the VIs

Frequency refining is an important spectrum analyzing tool, and is one of the main function of signal processing and the virtual instrument. This paper introduces several typical frequency refining analysis methods including DFT and multiple modulation and so on. It also probes into their advantages and disadvantages, and proposes a new frequency refining method combining subband decomposing DFT and multiple modulation, which inherits the advantages of multiple modulation, needs not to design a specific filter, reduces the amount of calculation, and is fit for real-time refining analysis. At last, it exhibits several frequency refining algorithm and their effects with applications in virtual instruments.