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1.
多维分配模型在构造关联代价函数时,直接利用极大似然估计值代替目标的真实位置信息,未考虑极大似然估计所引入的随机误差。针对此问题,提出一种基于瑞利熵的多无源传感器数据关联算法。该算法利用瑞利熵度量量测后验概率密度函数与伪量测概率密度函数之间的差异,构造关联代价函数。仿真实验结果表明:该算法有效地提高了关联正确率,具有较好的关联性能。  相似文献   

2.
针对单传感器在多机动目标跟踪系统中不能很好地处理目标数目变化与突发机动的问题,提出了多传感器多机动目标跟踪的概率假设密度滤波算法.以CPHD滤波算法为理论基础,同时递推概率假设密度(PHD)函数和基数分布,避免了多目标多传感器的数据关联问题.结合自适应当前统计模型,选择3个雷达作为跟踪目标的传感器,相比于单传感器降低了信息的模糊度,提高了可信度.仿真结果比较表明了多传感器CPHD滤波算法在多目标跟踪方面的性能优势.  相似文献   

3.
需求关联性现象普遍存在于顾客购买行为中,然而大多数库存管理方面的研究假设产品需求相互独立,忽视关联性造成的影响,可能导致严重的缺货现象发生。针对存在需求关联性情况下具有库存容量限制的多供应商电商库存分配问题,应用FP-Growth算法从订单数据库中挖掘得到关联规则,并将关联规则抽象为一种约束,建立双目标随机规划数学模型,通过分段线性拟合方法对非线性目标函数和约束进行处理。采用非支配排序遗传算法(NSGA-Ⅱ)对模型进行求解,基于“先知种群”改进种群初始化过程,以提升算法收敛速度。使用真实数据的数值实验表明,基于关联规则的库存分配模型能以小幅度增加运营成本为代价,显著减少缺货数量。最后对库存容量、关联规则置信度和供应商个数进行敏感性分析,进一步为电商平台管理者提供了参考。  相似文献   

4.
一种新的多机动目标跟踪的GMPHD滤波算法   总被引:1,自引:0,他引:1  
针对多机动目标跟踪的传统数据关联算法约束条件苛刻、估计精度低、计算量大等问题,提出了一种基于随机集理论的非数据关联的多机动目标跟踪算法.该算法将高斯混合概率假设密度(GMPHD)滤波与"当前"统计模型的优点相结合,绕过了棘手的数据关联问题,能高效处理目标数较大的机动跟踪问题.在漏检、虚警、多机动目标交叉杂波复杂环境下进行了仿真实验,结果表明,该算法具有较高的跟踪精度和稳健的跟踪性能.  相似文献   

5.
为解决由多个二类代价敏感算法扩展而成的多类算法存在时间复杂度高和不能区分错分代价的问题,提出一种采用多类代价指数损失函数的多类代价敏感AdaBoost算法(MCCSADA)。为保证算法的代价敏感特性,首先设计一种满足代价敏感损失函数设计准则的多类代价敏感指数损失函数;然后将此损失函数作为评价分类器性能的标准,以最小化损失函数为目的使用逐步叠加模型推导算法的最优基分类器加权系数;最后使用多类代价损失函数和最优基分类器加权系数求解公式替换多类AdaBoost算法的损失数和加权系数求解公式,得到代价敏感的MCCSADA算法。使用UCI数据集对算法进行验证,实验结果表明:算法的稳定性得到了提升,退化现象被减弱;相比于由两类代价敏感算法通过一对一方法扩展而来的多类代价敏感算法,MCCSADA算法在大多数情况下能够取得更低的代价,而且具有较低的时间复杂度,在3类数据集上的时间复杂度降低约40%,并且随着类别数的增多效率提升更加明显。  相似文献   

6.
对多传感器多目标融合中的数据关联算法的研究及发展进行了回顾,指出了各个算法的适用范围及局限性,重点对概率数据关联算法及联合概率数据关联算法进行了分析;最后指出了数据关联算法的研究方向及将来的趋势。  相似文献   

7.
一种移动机器人SLAM中的多假设数据关联方法   总被引:1,自引:0,他引:1  
针对移动机器人同时定位与建图(SLAM)中的局部数据关联问题,提出一种基于粒子滤波的多假设数据关联方法.该方法将数据关联问题转换成离散优化问题,利用多个粒子来维持多种数据关联假设,通过计算关联代价来获得粒子权重,用基本剪枝技术在粒子重采样过程中滤除错误的数据关联假设.研究结果表明:该方法弥补了经典的数据关联方法中关联假设一旦确定就不能修改的不足;与ICNN和JCBB数据关联方法相比,该方法能获得更正确的数据关联结果和更高的定位精度.  相似文献   

8.
为快速实现多目标数据的关联,将蚁群优化(AGO)算法和粒子群优化(PSO)算法相结合,提出了一种群智能混合算法.以跟踪门确定目标的有效量测,以新息的似然函数描述量测与目标的关联关系,建立多目标数据关联的组合优化模型.利用交叉变异的PSO算法求解出该优化组合模型的次优解,再将该次优解作为蚁群位置和信息素初始化的依据,利用ACO算法对目标函数的解进行细搜索以求得更优解.仿真实验结果表明,该算法能够有效地提高关联准确性和收敛速度.  相似文献   

9.
针对传统最近邻数据关联算法正确率较低且容易出现漏关联的问题,提出一种多特征加权的最近邻关联算法。根据智能车环境感知系统获得的障碍物特征数据,定义了一种相似度函数,提出基于生命周期计算有效关联度的方法,从而判定目标是否关联;基于卡尔曼滤波对关联目标进行迭代更新,实现对目标的跟踪;通过实验对比了静止目标、无交互的低速运动目标和有交互的低速运动目标的跟踪轨迹。结果表明,与传统的最近邻数据关联算法相比,所提出的改进算法可以实现对低速运动目标准确连续的关联跟踪,不会出现目标丢失或位置突变的现象,且跟踪目标的交互与遮挡对跟踪效果影响较小,具有较高的有效性与实用性。研究结果可为智能车辆的目标跟踪设计提供参考。  相似文献   

10.
提出了一种新的基于声震传感网的机动目标跟踪算法,即在Rao-Blackwellized蒙特卡洛数据关联(RBMCDA)算法基础上,引入代价函数,根据代价函数的可信度和误差偏离度实时在线更新测量噪声模型参数.仿真结果表明:相比于RBMCDA算法,该算法不依赖于观测噪声的精确建模,在节点频繁切换情况下仍具有很好的自适应性;...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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