电子差速履带车辆转向转矩神经网络PID控制

根据电子差速履带车辆转向动力学和运动学分析,提出一种电子差速履带车辆转向转矩模拟神经网络PID(ANNPID)控制策略,由双电动机转向转矩协调控制、ANNPID控制和感应电动机转矩控制组成.通过建立双感应电动机独立驱动履带车辆电子差速转向控制系统,实现基于ANNPID控制的转向转矩协调分配和基于模型参考自适应控制(MRAC)的感应电动机间接磁场定向(IFOC)转矩控制.采用该策略,在不同转向半径的行驶转向工况、0.5B半径转向工况和中心转向工况下的实车试验结果表明,低速转向具有较好的操控性能.     

牛肉新鲜度的电子鼻检测技

为了简单、快捷、准确地检测牛肉新鲜度,建立了电子鼻检测系统.根据牛肉产生的气味和传感器实验,合理地选用了气敏传感器阵列.为提高电子鼻传感器灵敏度,对购置的传感器进行了改进.利用生物嗅觉的研究成果,开发出仿生嗅觉鼻道结构.为了提高电子鼻系统小样本训练的识别率,提出了用支持向量机(SVM)算法识别牛肉新鲜度的方法.应用电子鼻系统对储藏7 d不同新鲜度的牛肉进行了识别实验,识别率达到99.25%.结果表明电子鼻检测牛肉新鲜度是可行的.     

电子鼻技术在粮食质量检测中的应用

对消费者来说,粮食的气味也是衡量其质量的一个重要标准.电子鼻是一种新颖的仿生系统,是用于分析、检测挥发性气味的仪器.为此,综述了电子鼻在粮食质量检测中的应用,主要包括粮食霉变、虫害和储藏年限等方面的研究及其应用现状;最后,展望了电子鼻在粮食检测中的应用前景.     

浅析网络环境下的期刊信息服务

笔者通过对网络环境下期刊信息服务工作中的一系列变化的分析，提出了加强期刊信息服务的举措。以进一步提高期刊信息服务的质量。     

Electronic feed stations for feeding concentrates to pregnant ewes on commercial sheep farms

ABSTRACT

The aim of this study was to investigate the use and capacity of electronic feed stations (EFS) on commercial sheep farms. The study was conducted on four commercial farms and the numbers of pregnant ewes per EFS were 36, 70, 72 and 80, respectively. Each farm was visited once and behavioural observations were carried out. In addition the date and time for both entering and leaving the EFS and the amount of concentrates dispensed at each visit for extracted. The vast majority of the ewes used the EFS regularly. The number of rewarded visits per ewe per day varied from 3.2 to 5.9, whereas the number of unrewarded visits ranged from 6.0 to 21.5 per ewe per day. We conclude that feeding concentrates to groups of pregnant ewes in EFS function satisfactory, but the design of the entrance and exit gate still have to be improved considerably.     

Determination of the botanical origin of honey by sensor fusion of impedance e-tongue and optical spectroscopy

The aim of this study was to discriminate four commercial brands of Portuguese honeys according to their botanical origin by sensor fusion of impedance electronic tongue (e-tongue) and optical spectroscopy (UV–Vis–NIR) assisted by Principal Component Analysis (PCA) and Cluster Analysis (CA). We have also introduced a new technique for variable selection through one-dimensional clustering which proved very useful for data fusion. The results were referenced against standard sample identification by classical melissopalynology analysis. Individual analysis of each technique showed that the e-tongue clearly outperformed the optical techniques. The electronic and optical spectra were fitted to analytical models and the model coefficients were used as new variables for PCA and CA. This approach has improved honey classification by the e-tongue but not by the optical methods. Data from the three techniques was then considered simultaneously. Simple concatenation of all matrices did not improve the classification results. Multi-way PCA (MPCA) proved to be a good option for data fusion yielding 100% classification success. Finally, a variable selection method based on one-dimensional clustering was used to define two new approaches to sensor fusion, and both yielded sample clusters even better defined than using MPCA. In this work we demonstrate for the first time the feasibility of sensor fusion of electronic and optical spectroscopy data and propose a new variable selection method that improved significantly the classification of the samples through multivariate statistical analysis.     

人工味觉系统在茶叶品质评价中的应用进展

综述人工味觉系统在茶叶感官品质评价中的应用进展,主要包括茶类区分、品质相关性分析、品质定量分析等,并提出ATS(Artificial taste systems)在茶汤预处理标准化、传感器稳定性和灵敏度的提高、模式识别技术的开发等方面的发展前景.     

基于VB的MIDI电子琴改进

提出了MIDI电子琴的实现方法,给出了多媒体API时间函数,支持鼠标和键盘弹奏,并且具有录制和回放功能,有利于电子琴的学习和指导.经实践,该MIDI电子琴实用、易操作,具有良好的功能.     

电子鼻在畜禽养殖场中的应用及研究进展

畜禽养殖场产生的恶臭气体是重要的环境污染因子,常规的检测技术如三点臭袋法费时费力,易受人为因素影响; 气相色谱-质谱联用法(GC-MS)耗时较长、耗费较高,不能确定混合气中各物质对恶臭的贡献份额,无法把恶臭结果与感官嗅觉相关联。这两者均不利于快速准确地评价恶臭污染状况。本文介绍了电子鼻的基本原理及其在畜禽养殖场恶臭管理中的应用,总结了国内外电子鼻技术的发展现状,阐明了电子鼻开发过程中的重点内容,并对今后电子鼻的发展趋势做出了预测和展望。     

电子导师制在农科类专业教学中的应用

介绍了电子导师制的内涵,针对农科类专业学习资源短缺、教学方法陈旧、导师严重不足、师生交流困难的问题,提出了电子导师制在农科类专业教学中的应用策略。