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61.
Wang Chang-biao Tu Jian-nan Jian Hua-bei Sun Yan 《International Journal of Infrared and Millimeter Waves》1986,7(7):1005-1035
The kinetic theory based on the expansion of local field in the guiding center coordinate system, presented by paper[1]–[3], has successfully developed into a theoretical system. The mathematical background and physical explanation of setting up the guiding center coordinate system is expounded in the paper. By using the methods of the guiding center and waveguide coordinate systems respectively, the same dispersion equations for interaction of an axially symmetrical single momentum electron beam with TEmn field in the circular waveguide are rigorously derived. A number of mistakes in paper[4] are indicated as well. 相似文献
62.
图像关注焦点(FOA)检测是基于人眼视觉关注模型的图像感兴趣区提取的关键技术。为了更加精确、合理地搜索图像关注焦点,提出一种基于双阈值视觉关注模型的FOA检测算法。算法首先提取图像的亮度、颜色、方向和离散矩变换(DMT)特征,生成各个特征对应的特征图;然后将各特征图合并为一张包含多种特征的显著图;最后根据显著图的灰度直方图建立静态阈值与动态阈值,确定图像关注焦点的位置与数量。实验结果表明:新算法在图像关注焦点检测的准确性上较Itti模型有更为优秀的表现,更符合人眼视觉的关注习惯。 相似文献
63.
In this paper, we investigate an optimal reinsurance and investment problem for an insurer whose surplus process is approximated by a drifted Brownian motion. Proportional reinsurance is to hedge the risk of insurance. Interest rate risk and inflation risk are considered. We suppose that the instantaneous nominal interest rate follows an Ornstein–Uhlenbeck process, and the inflation index is given by a generalized Fisher equation. To make the market complete, zero-coupon bonds and Treasury Inflation Protected Securities (TIPS) are included in the market. The financial market consists of cash, zero-coupon bond, TIPS and stock. We employ the stochastic dynamic programming to derive the closed-forms of the optimal reinsurance and investment strategies as well as the optimal utility function under the constant relative risk aversion (CRRA) utility maximization. Sensitivity analysis is given to show the economic behavior of the optimal strategies and optimal utility. 相似文献
64.
提出了含利率因素的复合二项双险种风险模型,并在有关假设的基础上,给出了此模型下保险公司稳定经营的必要条件;证明了索赔时刻的盈余过程是一马氏过程和调节系数的存在性,并采用递归方法得到了模型的破产概率的上界估计. 相似文献
65.
伦理学最核心、最基本的问题之一是义利之辨的问题。本文从儒家传统的义利之辨出发,结合信息社会的时代特点,探讨长久以来在这些思想影响下的中华民族过度强调集体意识和国家意识的民族特点,以及现阶段在不损害前两者利益的前提下应当更加呼唤个体意识等问题。 相似文献
66.
关于“产业技术创新战略联盟”——我的认识与理解 总被引:3,自引:3,他引:0
文章概述了在PcB中创建“产业技术创新战略联盟”的基本目的、要求和条件。 相似文献
67.
The biodegradation rate and biocompatibility of poly (d, / -lactide) (PDLLA)in vivo were evaluated. The aim of this study was to establish a nerve guide constructed by the PDLLA with 3-D microenvironment and
to repair a 10 mm of sciatic nerve gap in rats. The process of the nerve regeneration was investigated by histological assessment,
electrophysiological examination, and determination of wet weight recovery rate of the gastrocnemius muscle. After 3 weeks,
the nerve guide had changed from a transparent to an opaque status. The conduit was degraded and absorbed partly and had lost
their strength with breakage at the 9th week of postoperation. At the conclusion of 12 weeks, proximal and distal end of nerves
were anastomosed by nerve regeneration and the conduit vanished completely. The results suggest that PDLLA conduits may serve
for peripheral nerve regeneration and PDLLA is a sort of hopeful candidate for tissue engineering. 相似文献
68.
We present a region of interest (ROI) generation method specialized for nighttime pedestrian detection using far-infrared (FIR) images. Because pedestrians typically appear brighter than background in FIR images, previous research efforts primarily attempted to extract ROIs based on the intensity threshold. However this approach has problems resulting from the intensity variances of pedestrians due to their clothing and, especially in urban scenarios, and other heat sources that emit more heat than the pedestrians. In this paper, we propose a novel ROI generation method that is based on combining image segments instead of using the intensity threshold. In order to minimize dependence on brightness, we utilize the low-frequency characteristics of FIR images. As a result, our proposed method generates a small number of ROIs at an acceptable miss rate and the generated ROIs provide advantages for classification because the pedestrians are satisfactorily arranged within a bounding box. Experiments conducted indicate that our proposed method performs reliably in urban scenarios. 相似文献
69.
70.
研究各期存款(包括购国库券)利率及银行取款政策后发现:每年奖金额均来自于存款的利息;若每笔本金到取款时能获得最大综合本利率,则奖金额就可获得最大值.据此,建立了基金使用模型,设计了一个有效的算法,并通过编程在计算机上实现了这个算法,成功地解决了三种情况下(①只存款不购国库券;②可存款也可购国库券;③第3年的奖金比其他年度多20%)最佳基金存储设计问题,并对每年奖金额不等、年数n任意等都有效. 相似文献