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马保国 《武汉理工大学学报(材料科学英文版)》2011,26(6):1211-1214
The property of reclaimed asphalt pavement(RAP) mixture will be affected mainly by composition of old asphalt/soil and cement
content in CIR system. We studied the relationship between A/S and cementitious materials. It showed that if there was no
soil in RAP, the unconfined compressive strength was only from 0.18 MPa to 1.07 MPa even if adding cement was from 2% to 6%,
and RAP samples collapsed during conserving in water. The optimum water content rose from 6.5% to 11% with the declining of
A/S from S=0 to A/S=1/5. Five RAP samples all got the maximum compressive strength when A/S=5/5, and the maximum compressive
strength of the samples adding 6% cement was 3.17 MPa. It showed that the capacity of RAP was not only affected by A/S, but
also by the content of cement. The dynamic modulus of RAP will increase with the rise of loading frequency and decrease with
the temperature rising. SEM test showed that C-S-H interlacing formed the netted structure, and it enwrapped the aggregate
and improved the strength of RAP. 相似文献
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介绍了机车综合无线通信设备CIR在铁路和谐号大功率机车上的应用情况,重点分析了CIR常见故障产生的原因及处理方法,并预测了CIR设备在和谐号大功率机车上未来的发展趋势。 相似文献
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基于TD-SCDMA系统的快速频率估计算法 总被引:1,自引:1,他引:0
提出了一种应用于TD-SCDMA系统中的快速频率估计算法.这种算法利用训练序列估计信道冲击响应,恢复不受信道干扰的发送信号;然后利用最大似然估计算法和二分数值估计算法,估计出较为准确的频率偏移值.仿真表明,该算法比常用的频率估计算法具有更低的复杂度,而且在高斯白噪(AWGN)和多径衰落环境下,均能够对TD-SCDMA系统中的频率偏移获得较为准确的估计结果. 相似文献
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为了提高CIR利率期限结构模型中的状态估计精度,建立了该问题的离散非线性滤波模型,采用高斯粒子滤波法进行状态近似最优估计.相对于文献中普遍采用的扩展卡尔曼滤波方法,高斯粒子滤波法避免了线性近似带来的误差,利用基于重要性采样得到的高斯分布来近似状态变量的后验分布,具有更强的状态估计能力.仿真实验比较了高斯粒子滤波和扩展卡... 相似文献
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This paper describes an ICI mitigation method based on the generalized data‐allocation of (1, ?β) for orthogonal frequency division multiplexing systems. To improve the performance of the ICI mitigation for the higher‐frequency offset, we propose an efficient search algorithm to generate the sub‐optimal parameter β for maximizing the carrier‐to‐interference ratio (CIR). The CIR and bit error rate performances of the proposed method were derived in this paper. The performances with different carrier frequency offset scenarios were evaluated by computer simulations. According to the simulation results, the performance of the proposed ICI mitigation scheme is better than that of the conventional ICI self‐cancellation scheme and is nearly the same as that of the ICI self‐cancellation scheme for the optimal parameter β. Additionally, the proposed ICI mitigation scheme has a dramatically reduced hardware complexity in comparison with the ICI self‐cancellation scheme for the optimal parameter β. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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本文主要研究Cox-Ingersoll-Ross(CIR)随机利率模型下保险公司的最优投资和再保险问题.假设保险公司投资于金融市场中的无风险资产、零息债券和多种股票.此外保险公司购买比例再保险合约以转移承保风险.模型中,我们用仿射过程刻画随机利率,通过扩散过程模拟保险公司盈余过程,即用连续过程近似跳过程.保险公司的目标是通过保险投资最大化终端财富的期望幂效用.由于保险公司的财富过程不是自融资过程,在求解过程中,我们先将原优化问题转化为自融资问题,通过随机最优控制方法导出相应的HJB方程,进而得到最优投资、再保险策略和幂效用函数下的最优值函数.我们发现随着风险厌恶系数的增大,公司投资于股票的比例会降低,初始利率越高,保险公司终端财富的值函数越大.最后,我们给出了保费率、利率参数和风险厌恶系数对投资策略、投资效用的敏感性分析. 相似文献
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