内江市公园绿地土壤重金属Cu分布研究

对内江市大干园、塔山公园、大洲广场、人民公园0-20cm土层中的Cu、有机质和pH值进行研究,以农耕地为对照,结果表明：（1）土壤中Cu含量塔山公园显著低于人民公园,各公园绿地与农耕地差异不显著,各公园绿地土壤Cu为国家一级标准;（2）不同坡位Cu含量总体表现为：下坡＞中坡＞上坡;（3）各绿地土壤pH值为7.4～8.33,有机质含量差异不显著;（4）公园绿地土壤中Cu含量与有机质、pH值之间相关性不显著.     

浅谈如何调动学生的学习兴趣,优化数学教学

作为数学老师,平生最大的愿望就是使每一个学生能轻松愉快地学好数学.经过多年的教学,我认为优化课堂教学是实现这一愿望的重要途径.而如何优化课堂教学,学生学习兴趣的调动起着至关重要的作用.     

新形势下应用型高校无机化学教学初探

针对当前地方性工科院校无机化学教学现状,提出应对无机化学进行教学内容和教学方法的改革,并从教学内容、教学模式、创新教育等方面进行了尝试和探索.     

基于到达时间差的无线传感器网络中Sybil攻击检测方案

As wireless sensor networks （WSN） are deployed in fire monitoring, object tracking applications, security emerges as a central requirement. A case that Sybil node illegitimately reports messages to the master node with multiple non-existent identities （ID） will cause harmful effects on decision-making or resource allocation in these applications. In this paper, we present an efficient and lightweight solution for Sybil attack detection based on the time difference of arrival （TDOA） between the source node and beacon nodes. This solution can detect the existence of Sybil attacks, and locate the Sybil nodes. We demonstrate efficiency of the solution through experiments. The experiments show that this solution can detect all Sybil attack cases without missing.     

GM（1，N）－2模型及其在机器运行状态预测中的应用

根据现场特点，提出灰色非等间隔优化模型—ＧＭ（１，Ｎ）－２模型，对机器运行状态进行预测。并根据滨海轮的实测信号，对模型进行了检验。     

电动工业车辆供电电流的控制及直流牵引电动机暂态过程分析

本文根据电动工业车辆的牵引特性,讨论了直流牵引电动机和牵引蓄电池的匹配问题。提出一种可对电动工业车辆工作状态进行检测与控制的方法,从而改善直流牵引电动机在大负荷运行时的供电状况,提高蓄电池的工作容量和使用寿命。同时,对直流牵引电动机的暂态过程进行了分析。     

我国企业体育发展现状与对策研究

文章从企业体育的概念、作用入手,采用调查访问、文献资料等研究方法,重点对我国企业体育的发展现状及存在的主要问题进行分析,并提出我国企业体育的发展对策.以期为我国企业体育的发展指明方向,促进企业体育有序、高效地开展.     

Distributed fusion receding horizon filtering for uncertain linear stochastic systems with time-delay sensors

A new distributed fusion receding horizon filtering problem is investigated for uncertain linear stochastic systems with time-delay sensors. First, we construct a local receding horizon Kalman filter having time delays (LRHKFTDs) in both the system and measurement models. The key technique is the derivation of recursive error cross-covariance equations between LRHKFTDs in order to compute the optimal matrix fusion weights. It is the first time to present distributed fusion receding horizon filter for linear discrete-time systems with delayed sensors. It has a parallel structure that enables processing of multisensory time-delay measurements, so the calculation burden can be reduced and it is more reliable than the centralized version if some sensors turn faulty. Simulations for a multiple time-delays system show the effectiveness of the proposed filter in comparison with centralized receding horizon filter and non-receding versions.     

History-dependent modified sliding mode interception strategies with maximal capture zone

In order to construct the guidance strategy in a realistic nonlinear noise-corrupted interception endgame against a maneuverable target, a linearized zero-sum differential game is considered. Assuming perfect information in this game, sufficient conditions are established, which guarantee that a continuous interception strategy with memory (history-dependent) has the maximal capture zone. Two examples of such a strategy are analyzed: a modified super-twisting second-order sliding mode control and a modified integral sliding mode control. Simulation results of the original nonlinear interception endgame demonstrate that these strategies considerably reduce the chattering created by the classical game optimal bang-bang strategy without deteriorating the homing performance.     

应用交互式电子白板保证课堂的有效性

交互式电子白板为课堂互动、师生互动、生生互动提供了技术可能和方便。利用电子白板完成呈现、展示、交流、互动、合作,拓展了教学资源,优化了教学过程．激发了学生学习兴趣,优化了数学课堂教学程序．保证了教师的备课、上课、评价、反思的有效性．大大提高了数学课堂教学的效率。