对时间的分数阶扩散方程在图像恢复中的应用

提出了一种包含对时间的分数阶导数的非线性扩散方程,它是对Perona-Malik的非线性扩散方程和Cuesta提出的方程的推广,介于非线性抛物方程和非线性双曲方程之间,从而能有效地控制扩散过程,使得在去除图像噪声的同时能够尽可能地保留图像的边缘等细节信息。数值试验结果显示,该方程比Perona-Malik的非线性扩散方程有更好的去噪效果。     

对称Toeplitz—plus—Hankel矩阵特征值的快速算法

利用了n阶对称Toeplitz—plus—Hankel矩阵的结构特点和对称性,给出了计算该类矩阵所有特征值的一个快速算法．该算法的计算复杂度为o（n^2 logn）,比文献[1—2]所给的算法来得少．     

失效概率的估计及其性质

E—Bayes估计法在无失效数据情形给出了失效概率的E-Bayes估计的定义,并在此基础上给出了失效概率的E—Bayes估计。文章在E—Bayes估计法基础上,给出了失效概率的另外两个E—Bayes估计,并给出了失效概率的E—Bayes估计的性质。最后,给出了数值算例,结果表明E-Bayes估计法可行且便于应用。     

金免疫层析试条检测线的提取

针对反射型光纤传感器测量金免疫层析试条反应结果的工作原理和不足,在扫描检测的基本原理下,提出积分扫描的方法提取试条的检测线,并且分析该方法的可行性,给出了检测线提取的程序流程图,试验结果表明：该方法在检测线不倾斜的情况下,可以较精确地提取检测线。     

我国寿险需求的结构分析

在既有研究成果的基础上,结合我国实际情况,综合考虑了影响我国寿险需求的经济因素、政策因素、人口因素、科技因素,并引入虚拟变量来反映1995年我国《保险法》和一系列配套行政法规及部门规章制度制定以后对保险业的影响。以1990~2008年的相关数据为基础,运用多元线性回归、岭回归等统计方法,借助SPSS13.0统计软件,通过建立岭回归模型对上述因素进行定量分析,对寿险需求进行结构分析。结果表明：居民收入是寿险需求的决定性影响因素,而GDP、社会保障支出、科技投入、人口因素对寿险需求都有正的效应,而通货膨胀对寿险需求有抑制作用。     

Reversible changes in fluorescence of bacterial endospores found in aerosols due to hydration/drying

In this study we show that the room temperature multiwavelength autofluorescence signature of wet Bacillus endospores is considerably different from that of the dry endospores. The fluorescence is measured with excitation wavelengths of 300–500 nm with 50 nm steps. Small differences are observed between the dry and the re-dried spores. The fluorescence spectra support the model of reversible water migration between inner spore compartments and the environment. Characteristic information is extracted from spectral fluorescence excitation–emission contours for these spores by applying the dimensional reduction of data techniques known as principal component analysis. Aerosol detection and identification techniques relying on fluorescence must take into account the hydration state of the spores and recognize the ability of the spores to rapidly change their state of hydration.     

Finite Time Synchronization of Delayed Quaternion Valued Neural Networks with Fractional Order

Neural Processing Letters - In this article, the finite time (FT) synchronization problem of fractional order quaternion valued neural networks with time delay is investigated. Without separating...     

Nb2AsC结构及热力学性质的第一性原理研究

采用基于密度泛函理论的第一性原理方法研究Nb₂AsC的结构、弹性和热力学性质,与其他实验值和理论值相比,该文计算的Nb₂AsC晶体结构常数、体弹模量及其对压力的一阶偏导均与之符合较好;计算获得的常压弹性常数与其他理论值比较一致,由此根据力学稳定性准则,判定六方晶系Nb₂AsC是力学稳定结构。预测了Nb₂AsC的杨氏模量。结果表明,六方晶系Nb₂AsC是各向异性。采用准谐德拜模型,模拟了压力和温度对Nb₂AsC的等容热容、等温弹性模量、热膨胀系数和德拜温度等热力学性质的影响。     

公共自行车服务系统推广模型

针对公共自行车服务系统优化问题,采用浙江省温州市鹿城区某20天借车和还车的原始数据,利用Excel处理原始数据并建立图表,从而得出了对服务站点位置分布、各站点自行车锁桩和自行车数量配置相应的调整措施,最终将公共自行车服务系统加以改进推广。     

Multipath optical thermometry realized in CaSc2O4: Yb3+/Er3+ with high sensitivity and superior resolution

Design and fabrication of contactless optical thermometer with rapid and accurate performance has become a research hotspot in recent years. Herein, CaSc₂O₄: Yb³⁺/Er³⁺ is employed as the intermediary for temperature sensing under the excitation of 980 nm, which is proven to afford an ultra-sensitive and high-resolution optical thermometry in multiple ways based on the fluorescence intensity ratio (FIR) technology. The optimal thermal sensing behaviors are realized by the FIR of Er³⁺:²H_11/2 → ⁴I_15/2 to ⁴S_3/2 → ⁴I_15/2 transition, which has a relative sensitivity of 1184/T² and a minimal resolution of 0.03 K along with a maximal absolute error of 0.96 K. Besides that, the FIR between the thermally coupled Stark sublevels of Er³⁺:⁴F_9/2 manifold (FIR_R) as well as that of Er³⁺: ⁴I_13/2 manifold (FIR_N) can also provide excellent optical thermometry. The relative sensitivity of FIR_R-based and FIR_N-based optical thermometers are calculated to be 402/T² and 366/T², respectively, with a same minimal resolution of 0.09 K, which possess the potential to be used for biomedicine due to the inherent advantage of their operating wavelengths located in the biological window. The results demonstrate that CaSc₂O₄: Yb³⁺/Er³⁺ is a promising candidate for temperature sensing with multipath, high sensitivity, and superior resolution.