Results from the monitoring of pesticide residues in fruit and vegetables on the Danish market, 2000-01

To check compliance with the maximum residue levels in foods and to monitor the residue levels to enable an evaluation of the exposure of the Danish population to pesticides, a monitoring programme for pesticides residues in fruit and vegetables was performed. Sampling plans were designed based on previous findings and on consumption data. Samples (n = 4404) of mainly fresh conventionally and organically grown fruit and vegetables were collected at wholesalers and importers and at food processing companies. Of the samples, 3% were frozen products and 5% organically grown. Of the samples, 34% were of Danish origin, with 66% from other countries. Two accredited laboratories performed analyses of the samples using capillary gas chromatography, liquid chromatography and a spectrophotometric method. Reporting levels were set at the lowest calibration level or at the limit of determination. Residues were found in 60% of the samples of fruit but in only 18% of the vegetable samples. Residues above the maximum residue levels were found in 6% of all samples of fruit and in 2% of the vegetable samples.     

变频器在龙门铣床上的应用

介绍龙门铣床的直流调速控制系统的改造方案，根据龙门铣床工作台运动过程及原直流电机的容量来选择交流电机和变频器并对变频器的功能进行设定。     

煤矿微机安全生产监测监控系统

本文介绍了分站式系统、无分站式系统以及复全式系统的特点，主要论述了复合式微机安全生产监测监控的结构、性能和应用。     

Modeling of streaming and elastic flow integration in OFDMA-based IEEE802.16 WiMAX

We study in this paper the capacity of the downlink of OFDMA-based IEEE802.16 WiMAX system in the presence of two types of traffic, streaming and elastic. We focus in particular on the impact of Adaptive Modulation and Coding (AMC) as well as inter-cell interference resulting from different frequency reuse schemes. Several performance measures, namely blocking rates, mean transfer time and the mean number of collisions between two OFDMA WiMAX cells, are then derived and quantified. We show that reuse partitioning results in a higher blocking rate at the appreciable gain in terms of lower mean transfer time for users close to the base station as well as a lower number of collisions which implies a higher throughput.     

己二胺装置第一脱氢塔分离能力不足的原因分析及对策

对新建己二胺装置中第一脱氢塔分离能力不足的原因进行了分析，并采取针对性的措施；从而使己二胺装置整体负荷达到设计能力。     

智能建筑中空调监控系统的交互界面设计

智能建筑是根据用户需求将建筑物的结构、设备、服务和管理进行最优组合以提供高效、舒适、便利的人性化建筑环境。文章以交互界面为切入点,用户需求为核心,对某智能建筑中空调监控系统的交互界面设计进行了探讨,以期为其它工业控制系统的交互界面设计提供参考。     

无线传感器网络（WSN）在花卉大棚环境监测中的应用研究

针对传统花卉大棚环境参数监测系统的某些缺点,本文对基于Zigbee技术的无线传感器网络在花卉大棚中的应用可行性进行分析和研究,并建立了花卉大棚无线环境监测系统,使得该监测系统的各节点位置、监测范围、节点扩展性、节点间距离都得以改善和提高。     

物联阿技术在电梯监测报警管理系统中的应用

本文首先对当前城市电梯运营状况作了分析,然后对利用物联网技术监测与管理电梯的必要性进行了探讨。介绍了物联网技术在城市电梯监测报警管理系统中的应用原理,重点描述了无线监测终端的设计和功能。     

基于LABVIEW的电能质量在线监测和分析

本文讨论了国家标准规定的电能质量参数的计算方法,并利用LabVIEW创建了频率、谐波、三相不平衡度的测量和数据分析程序,同时采用DataSocket技术进行网络通信。设计出了基于LABVIEW的电能质量在线监测和分析系统,该系统提高了在线监测的灵活性和参数的精度并能及时记录相关的电压事件,能够长时间稳定工作,具有一定的实用价值。     

车辆TPMS轮速传感器误差消除方法研究

轮胎压力监测系统能够实时地自动监测行驶中汽车的轮胎气压,对于提高行车安全具有重要的意义。基于轮胎压力监测系统硬件平台,阐述了轮速信号的获取,研究了异点剔除方法,提出了基于弹性BP神经网络分析轮速传感器误差的方法,实现了对轮速信号的修正。仿真和实验结果表明,该轮速传感器误差消除方法的精度可达2×10-4rad,能够显著降低传感器误差,提高轮速信号的获取精度。