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1.
针对传感器观测结果可能存在虚假甚至错误信息从而影响数据融合估计的问题,研究了一种度量多传感器观测结果一致性的测度算子.在进行数据融合估计之前,首先对多传感器的观测结果进行一致性检验,从而识别并剔除失效传感器的观测结果,最终获得一致性估计.该一致性测度算子基于Hampel粗差鉴别思想,同时考虑传感器的自支持度和传感器之间的互支持度,经过综合后给出传感器观测结果的一致性测度信息.仿真实验结果表明,该方法简单有效,能够准确识别传感器的虚假和错误观测结果,剔除失效传感器,同时能够给出传感器观测结果的质量评价,为数据融合估计提供可靠的一致性传感器组.  相似文献   

2.
对带相关噪声的多传感器系统,研究了事件触发的贯序和分布式融合估计算法.不同传感器之间的观测噪声同时刻相关,并与过程噪声一步相关.为了节省通信能耗,采用了事件触发传输机制,该机制依赖于每个传感器当前的观测值和上一个触发时刻的观测值.在事件触发条件下,提出了在线性最小方差意义上的最优贯序融合和分布式融合估计算法.所提出的贯序融合算法可以根据传感器观测数据到达滤波器的顺序进行实时处理,具有较小的计算负担.所提出的分布式融合算法可以对传感器观测数据进行并行处理,具有更好的可靠性.两种算法与事件触发集中融合算法具有相同的估计精度.仿真结果验证了算法的有效性.  相似文献   

3.
多传感器数据关联是现代多传感器系统中的一个重要问题.多传感器数据关联即是确定不同传感器系统观测到的若干测量信号是否来源于同一个目标.传统的数据关联方法通过形成关联矩阵,来求取关联矩阵的最优解,但是容易受到传感器性能的影响.为了降低传感器性能对关联结果的影响,提出了一种新的通过采用比较传感器测量信号之间的相对位置并提取相对位置模式的方法来获得不同传感器系统对应的目标匹配对的方法,并给出了一种改进的适用于传感器目标信号关联的匹配算法.这种方法充分利用了测量信号之间相对位置的内在特性.仿真结果表明传感器偏差对于采用相对位置进行数据关联的方法基本没有影响,并且这种方法整体性能上有所提升.  相似文献   

4.
云环境服务集群中作业提交存在着非均匀分布的问题,此问题会导致某一时刻作业聚集,从而引起作业的响应时间超出用户容忍范围。针对该问题,笔者在Hadoop平台下利用二级队列技术,提出一种基于队列的作业转移调度策略(JTSA)。实验结果表明,在作业数量某一时刻剧增的情况下,对总完成时间影响不大而且能够较大幅度提高作业的响应速度,随着作业数的增加,这种效果越明显。  相似文献   

5.
多传感器最大属性数据融合及其目标识别应用   总被引:8,自引:0,他引:8  
为解决干扰存在下目标分类识别问题 ,在数据融合的决策层上 ,利用属性集和属性测度的概念 ,提出了多传感器最大属性融合方法 ,既考虑了各传感器得到的数据 ,也考虑了各传感器所得数据的可信度。通过试验得到融合后的识别结果优于单传感器的识别结果 ,证明了多传感器最大属性融合方法的正确性和有效性  相似文献   

6.
为了提高集中式多传感器一致性数据融合的精度,在数据融合过程中,必须考虑从各传感器获得的数据可信度.为了克服现有一致性数据融合算法中定义的距离矩阵和关系矩阵存在的不对称性和主观性等缺点,本文定义了概率距离矩阵和基于统计置信度的关系矩阵,然后讨论了多正态分布共同均值的极大似然估计的统计性质和递推特性,并根据估计量的方差统计性质提出了一种基于动态层次聚类的多传感器一致性数据融合处理的方法,数据实验的计算结果表明,该算法优于现有的多传感器一致性数据融合方法.  相似文献   

7.
在冬季雨雪、冻雨、雨凇和雾凇等天气现象发生时,自动气象站风传感器转动部件容易发生冻结,造成风向风速观测数据缺测。为解决风传感器冻结的问题,设计一种基于分级加热技术的风传感器加热装置,采用多级加热元件组合控制的方式,实现自适应启动不同级别的加热模式。通过试验对风传感器加热装置性能进行测试,以及对风向风速观测数据进行处理分析,评估风传感器加热装置在气象观测业务中应用的可行性。结果表明,带有加热装置的风传感器起到了很好的防冻结作用,运行更加稳定;带有加热装置的风向风速数据完整性优于未带有加热装置的风传感器,两者风速具有较强的相关性,相关系数均在95%以上;两者风向一致性显著,均在80%以上,十分钟风向一致性优于两分钟风向一致性。可见,风传感器加热装置可有效减少风传感器冻结发生的次数,及时消除结冰层,降低观测人员设备维护工作量,提高风传感器运行的稳定性和数据的连续性,为风传感器加热装置应用于气象观测业务提供决策支撑。  相似文献   

8.
基于神经网络的多层感知器模型,结合滚动学习 预报机制,提出了一种异常数据实时检测方法.该方法在每个当前时刻通过最近的固定长度的历史数据训练神经网络,完成下一时刻的预报.通过神经网络模型残差,确定概率为P的置信区间.当下一时刻数据落入置信区间内,则该数据被判为正常;反之,则为异常.被判为异常的数据不再用作更新历史数据,而以相应的预报值代替.通过某300 MW燃煤火力电站实际过程数据的在线验证,结果证明了所提出方法的有效性.  相似文献   

9.
在多传感器多目标融合系统中,多传感器所提供的信息常常不同类,难以融合,建立多传感器多目标的随机集观测模型可以解决统一融合问题.基于随机集理论,根据虚警及漏测的情况,给出了目标的信任测度及其全局密度.从单传感器单目标推广到多传感器多目标,建立了实用的多目标随机集测量模型,并根据实例证明了该模型的实用性和有效性.  相似文献   

10.
为解决大规模异构低能力群组对目标的定位问题,提出一种基于概率融合的异构群组目标定位方法,将由节点传感器数据得到的目标概率分布图进行加权叠加融合后得到综合概率分布图,采用贝叶斯检查器对其中的显著区域进行检测识别,并提取出概率最大点,即为目标所在位置.仿真实验结果表明,所提方法能较好地解决大规模个体的定位问题,对静态目标的定位误差能较快地收敛到5 m左右,对运动目标的定位区域随目标的运动而增大,在某一时刻后误差范围稳定在65 m左右.  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.
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   

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 discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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