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991.
D-S证据理论在时-空信息融合中的应用 总被引:4,自引:1,他引:4
多传感器的信息融合技术应用于导航、目标跟踪、目标识别等很多领域。目前用于信息融合的主要方法就是证据理论技术。论文给出了三种基于D-S证据理论的多传感器多个测量周期的信息融合(时-空信息融合)的方法。在仿真实验中对这三种方法进行了比较,分布式有反馈的方法是三种方法中最好的。 相似文献
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上海浦江双辉大厦四层地下室的深基坑,共有三道钢筋混凝土支撑,其中第二道支撑位于B2层楼板中,结构施工困难。通过优化,将第二道支撑上移,并同步调整支撑平面布置,第三道支撑局部加强,使之避开结构,同时采取了分层分块、限时开挖的措施,获得了较好的效果。 相似文献
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Contactless and Rapid Discrimination of Improvised Explosives Realized by Mn2+ Doping Tailored ZnS Nanocrystals
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Zhaofeng Wu Chaoyu Zhou Baiyi Zu Yushu Li Xincun Dou 《Advanced functional materials》2016,26(25):4578-4586
In order to sensitively, selectively, and rapidly detect the constituents relevant to improvised explosive devices (IEDs), the sensing properties of ZnS nanocrystals (NCs) are regulated by tailoring the doping level of Mn2+. The responses of the sensors fabricated by ZnS NCs with different Mn‐doping levels (Mn:ZnS) toward the constituents, such as sulphur powder and black powder, generally increases first and then decreases with the increase of the concentration of doped Mn2+, and reaches the climate with an atomic ratio of 2.23% at room temperature. The sensory array based on eight sensors of Mn:ZnS NCs can realize the detection of two typical military explosives and six constituents relevant to IEDs within 7 s and can recover in 19 s. Furthermore, the fingerprinting of the constituents is achieved by pattern recognizing the inherent kinetics and thermodynamics of interaction between the sensory array and the constituents. Thus, a simple chemiresistive sensing strategy based on semiconductor NCs which can rapidly, supersensitively, and discriminatively detect the constituents relevant to IEDs is explored for the first time. 相似文献
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Shuryo Nakai Jinglie Dou James F. Richards 《International Journal of Food Properties》2013,16(1):149-164
Advantages of principal component similarity (PCS) as an unsupervised classification techniques compared to supervised methods are the detectability of outliers or anomalies, a capacity to classify continuum, easy identification of causes for grouping, and a potential of discovering new groups. The ability of detecting outliers or anomalies was utilized to eliminate panel members who were not appropriate for the classification purposes by using PCS scattergrams. After eliminating the unqualified panelists, the evaluation score tables were realigned from the one based on panelists to that based on samples. Accumulated principal component score were computed for the samples in a form of SPCi × Si, where PCi was the principal component score of sample i and Si was its proportion within the total variation. The conventional averaging algorithms of evaluated scores are useful, as this techniques absorbs the effect of unjustifiable negative scores reported by outliers. However, more reasonable summary scores for the samples could be obtained by eliminating unreasonable evaluation scores made by the outliers as well as by using the above new summary values. Differences in deviations of evaluation among attributes, such as those in likenesses of color and taste of meat products, were normalized. Specific training or selecting qualified panelists prior to panel evaluation is unnecessary when the information obtained from panel evaluation is required to reflect the variable broad patterns of consumer preference. Information obtained from consumer preference test based on cluster analysis, which was applied to a beverage, might be more readily recovered by using this new strategy. 相似文献
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Z. Dou C.F. Ramberg Jr. J.D. Toth L.E. Chase K.F. Knowlton 《Journal of dairy science》2010,93(2):830-839
Managing P on dairy farms requires the assessment and monitoring of P status of the animals so that potential overfeeding may be minimized. Numerous published studies have demonstrated that for lactating dairy cows, increasing P concentrations in diets led to greater P excretion in feces. More recent work reported that inorganic P (Pi) in 0.1% HCl extracts of feces (fecal extract Pi, g/kg) closely reflects dietary P changes. This has led to the proposal that 0.1% HCl fecal extract Pi may serve as an indicator of the animal's P status (adequate or excessive) when compared with a benchmark value. Here, we present the results of an extensive evaluation of the proposed fecal P indicator test. With samples (n = 575) from >90 farms, fecal total P (TP, g/kg) and fecal extract P were positively correlated with dietary P (X, g/kg): TP = 1.92X - 0.17 (R2 = 0.36); fecal extract P = 1.82X - 2.54 (R2 = 0.46). Fecal extract P was responsive to dietary P changes, whereas the remaining P, calculated as TP minus fecal extract P, was not. A provisional benchmark value of fecal extract P representing near-adequate P status was set at 4.75 g/kg. Assessment of the farm data using the benchmark indicated that 316 out of 575 data points were associated with possible P overfeeding. Advantages of the fecal-based test over feed-based analysis to assess P status are discussed. The fecal extract P method is a simple and practical test that can be used as an assessment tool for helping dairy producers improve P management and reduce their environmental footprint. 相似文献
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Real‐time streaming of shape deformations in a shared distributed virtual environment is a challenging task due to the difficulty of transmitting large amounts of 3D animation data to multiple receiving parties at a high frame rate. In this paper, we present a framework for streaming 3D shape deformations, which allows shapes with multi‐resolutions to share the same deformations simultaneously in real time. The geometry and motion of deforming mesh or point‐sampled surfaces are compactly encoded, transmitted, and reconstructed using the spectra of the manifold harmonics. A receiver‐based multi‐resolution surface reconstruction approach is introduced, which allows deforming shapes to switch smoothly between continuous multi‐resolutions. On the basis of this dynamic reconstruction scheme, a frame rate control algorithm is further proposed to achieve rendering at interactive rates. We also demonstrate an efficient interpolation‐based strategy to reduce computing of deformation. The experiments conducted on both mesh and point‐sampled surfaces show that our approach achieves efficient performance even if deformations of complex 3D surfaces are streamed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献