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排序方式: 共有10000条查询结果,搜索用时 218 毫秒
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文中提出了一种应用RBF神经网络对标准IMM算法中的卡尔曼滤波结果进行校正的方法。网络输人为预测误差、卡尔曼增益以及测量值与估计值之差.网络输出反映了由于目标机动所带来的滤波误差.将网络输出结果和直接由卡尔曼滤波求解得到的结果相加.可以得到更为准确的滤波值。同时.在网络的学习算法中.在网络权值矩阵的修正公式中增加了反映滤波残差的调整项.若卡尔曼滤波的残差较大,网络调整权值的幅度也相应增大。仿真结果表明.在目标发生机动转弯处.校正后的IMM算法的跟踪误差要明显小于标准IMM算法的跟踪误差.跟踪精度较高。 相似文献
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通过对挤出机固体输送段物料融解过程的分析,提出了通过在螺槽中垫高固体床,将熔化的熔融物挤进螺槽内侧的熔池中,而在螺槽内侧的熔池保持高度不变,从而使物料和熔融物相对分离,以提高熔化速率以及减少熔融物降解的新型螺杆模型。 相似文献
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OPAL J. WILLIAMS G.S. VIYAYA RAGHAVAN VALÉRIE ORSAT JIANMING DAI 《Journal of Food Biochemistry》2004,28(2):113-122
The applicability of microwave irradiation to assist the extraction of capsaicinoids from capsicum fruit was investigated. The procedure involved irradiation of 2 g samples in a closed-vessel followed by gas chromatography of capsaicinoid derivatives. The optimum conditions for extraction were determined to be acetone at 30% power for 7 min irrespective of ground or whole tissue.
The yield of the compounds extracted was significantly greater (P < 0.05) using microwave-assisted extraction (MAE) compared to traditional reflux and shaken flask methods. A single extraction step was efficient in recovering approximately 95% of the total capsaicinoid fraction in 15 min compared with 2 h for the reflux and 24 h for the shaken flask methods. Due to the considerable savings in time and energy as well as reliability, this technique is suitable for fast extraction of capsaicinoids from large samples. 相似文献
The yield of the compounds extracted was significantly greater (P < 0.05) using microwave-assisted extraction (MAE) compared to traditional reflux and shaken flask methods. A single extraction step was efficient in recovering approximately 95% of the total capsaicinoid fraction in 15 min compared with 2 h for the reflux and 24 h for the shaken flask methods. Due to the considerable savings in time and energy as well as reliability, this technique is suitable for fast extraction of capsaicinoids from large samples. 相似文献
66.
Distributed Rule-Regulated Spectrum Sharing 总被引:2,自引:0,他引:2
Lili Cao Haitao Zheng 《Selected Areas in Communications, IEEE Journal on》2008,26(1):130-145
Dynamic spectrum access is a promising technique to use spectrum efficiently. Without being restricted to any prefixed spectrum bands, nodes choose operating spectrum on-demand. Such flexibility, however, makes efficient and fair spectrum access in large-scale networks a great challenge. Prior work in this area focused on explicit coordination where nodes communicate with peers to modify local spectrum allocation, and may heavily stress the communication resource. In this paper, we introduce a distributed spectrum management architecture where nodes share spectrum resource fairly by making independent actions following spectrum rules. We present five spectrum rules to regulate node behavior and maximize system fairness and spectrum utilization, and analyze the associated complexity and overhead. We show analytically and experimentally that the proposed rule-based approach achieves similar performance with the explicit coordination approach, while significantly reducing communication cost. 相似文献
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A Ml (NiCoMnA1)5 hydrogen storage alloys was prepared by double-roller rapid quenching.Its microstructure, electrochemically and kinetic characteristic were studied.A uniform crystal phase with CaCu5 structure could be detected by XRD analyses, whose average grain size is 30 ~ 50 nm and the ratio of c/a of nano-crystal hydrogen storage alloy is larger.The hydrogen absorption/desertion p - C isotherms of alloy show that its fiat-performance is perfect and the magnetic stagnant effect is very little.An simulate cell is used for electrochemical measurement.Electrode is 10C, the capacity decreasing rate via the 450 cycles at 7C is less than 20%. 相似文献
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