为了设计一种以较小运算量获得较高测距精度的TOA(time of arrival)估计算法以适合节点运算能力有限的UWB(ultra wideband)无线传感器网络,提出了一种结合能量检测与匹配滤波的两步TOA估计方法.分析了该方法的工作原理,指出了第1步中DP(...为了设计一种以较小运算量获得较高测距精度的TOA(time of arrival)估计算法以适合节点运算能力有限的UWB(ultra wideband)无线传感器网络,提出了一种结合能量检测与匹配滤波的两步TOA估计方法.分析了该方法的工作原理,指出了第1步中DP(direct path)块检测成功率及第2步中匹配滤波门限因子设置的重要性.通过仿真对影响DP块检测成功率的两个因素,即DP块检测算法的选用和能量积分周期的设置进行了讨论.提出了依据能量采样序列中DP块与最小块比值DMR(DP to minimum energy sample ratio)动态设置匹配滤波门限因子的思想,并为其建立了数学模型.仿真结果表明,两步TOA估计方法在运算量比单一的基于匹配滤波的相干算法小很多的情况下,获得了比单一的基于能量检测的非相干方法更好的TOA估计性能,从而更适合应用于有低复杂度、低能耗设计需求的传感器节点中.展开更多
本文针对工业炸药生产过程和流通领域的实时监控问题，提出用RFID（Radio Frequency Identification，简称RFID）技术进行实时数据的获取，构建工业炸药实时监控信息系统。然后探讨系统的框架和功能结构，对系统实现的关键技术进行研究...本文针对工业炸药生产过程和流通领域的实时监控问题，提出用RFID（Radio Frequency Identification，简称RFID）技术进行实时数据的获取，构建工业炸药实时监控信息系统。然后探讨系统的框架和功能结构，对系统实现的关键技术进行研究，并提出一种工业炸药监管的新机制。展开更多
The combination of online or semi-online with deterioration jobs has never been researched in scheduling problems. In this paper, two semi-online parallel machine scheduling problems with linear deterioration processi...The combination of online or semi-online with deterioration jobs has never been researched in scheduling problems. In this paper, two semi-online parallel machine scheduling problems with linear deterioration processing time are considered. In the first problem, it is assumed that the deterioration rates of jobs are known in an interval, that is, bj ∈[0, α], where 0 〈α≤ 1 and bj denotes the linear deterioration rate. In the second problem, it is assumed that the largest deterioration rate of jobs is known in advance, that is, b = max1≤j≤n {bj }. For each of the two problems, a heuristic MBLS algorithm is worked out and its worst-case ratio is analyzed. At the same time, the worst-case ratio of the list （LS） algorithm is investigated and it is proved that all the ratios are tight.展开更多
基金Supported by the Major Program of the National Natural Science Foundation of China under Grant No.60432040(国家自然科学基金重点项目)
文摘为了设计一种以较小运算量获得较高测距精度的TOA(time of arrival)估计算法以适合节点运算能力有限的UWB(ultra wideband)无线传感器网络,提出了一种结合能量检测与匹配滤波的两步TOA估计方法.分析了该方法的工作原理,指出了第1步中DP(direct path)块检测成功率及第2步中匹配滤波门限因子设置的重要性.通过仿真对影响DP块检测成功率的两个因素,即DP块检测算法的选用和能量积分周期的设置进行了讨论.提出了依据能量采样序列中DP块与最小块比值DMR(DP to minimum energy sample ratio)动态设置匹配滤波门限因子的思想,并为其建立了数学模型.仿真结果表明,两步TOA估计方法在运算量比单一的基于匹配滤波的相干算法小很多的情况下,获得了比单一的基于能量检测的非相干方法更好的TOA估计性能,从而更适合应用于有低复杂度、低能耗设计需求的传感器节点中.
文摘The combination of online or semi-online with deterioration jobs has never been researched in scheduling problems. In this paper, two semi-online parallel machine scheduling problems with linear deterioration processing time are considered. In the first problem, it is assumed that the deterioration rates of jobs are known in an interval, that is, bj ∈[0, α], where 0 〈α≤ 1 and bj denotes the linear deterioration rate. In the second problem, it is assumed that the largest deterioration rate of jobs is known in advance, that is, b = max1≤j≤n {bj }. For each of the two problems, a heuristic MBLS algorithm is worked out and its worst-case ratio is analyzed. At the same time, the worst-case ratio of the list （LS） algorithm is investigated and it is proved that all the ratios are tight.
