A Systematic Analysis of Human Activity on Landform Evolution of Loess Plateau——Taking loess plateau area in Gansu Province as an example

It is common knowledge that landform evolutionary process is controlled bytwo processes,endogenic forces processes,and exogenic forces process.Endogenicforces and exogenic forces processes history is as long as the earth's history.Comparing with landform evolutionary history,human history is a very shortinstance.But people have to undertake cultivation,animal husbandry and otherproductive activities for their living since they came to the world.This affectslandform evolutionary process.Especially,the effect of human activity on landformevolution of loess plateau is becoming more and more violent for several thou-sand years.Watersoil erosion is one of very important landform evolution pheno-menon of loess plateau.The authors have studied water-soil erosion of loess pla-teau area in Gansu province as example,analyzed the effect of human activity onwater-soil erosion.Thus the position and the effect of human activity on landformevolution of loess plateau have been shown from one point.     

分布式系统的层次式命名方案设计

针对大规模分布式系统中对象迁移、网络和系统动态重构的要求,本文提出了一种层次式的命名和编址方案,它将对位置透明的标识（ＯＩＤ）和表示位置的地址（ＯＡＤ）二者结合起来标识对象．     

Q-正则Loewner空间中的拟对称映射

本文在Q-正则Loewner空间中用环模不等式刻划了拟对称映射.另外,在 Q-维Ahlfors-David正则空间中建立了拟对称映射作用下的Grotzsch-Teichmuller型 模不等式,它是通过伸张系数的积分平均来表示.     

微光成像系统的阈值探测理论和视距探测方程的研究

研究目前文献中常见的１８种微光成像系统探测方程之间的内在联系和异同之处，分析论证各种阈值探测理论和探测方程存在的问题和不足。在此基础上，从人眼的视觉理论和阈值特性出发，建立微光成像系统新的阈值探测理论模型，并分别导出微光直视系统和微光电视系统的视距探测方程。应用所导出的理论公式计算的数据与各种实际系统的实测数据进行了比较，证明新的阈值探测理论和视距探测方程是正确可靠的，且具有很高的精度。     

Low frequency limits of third-order harmonic coefficients for atomic hydrogen in any level of discrete energy spectrum

In this paper the analytical expression is derived for the third-order optical harmonic coefficients x _abcd ^v (,,) of the atomic hydrogen at very low frequencies 0 in many level of the discrete energy spectrum.The author expresses his thank to Prof. Nguyen Van Hieu for suggesting the problem and fruitful discussions.     

A Dynamic Anomaly Detection Approach Based on Permutation Entropy for Predicting Aging-Related Failures

Software aging is a phenomenon referring to the performance degradation of a long-running software system. This phenomenon is an accumulative process during execution, which will gradually lead the system from a normal state to a failure-prone state. It is a crucial challenge for system reliability to predict the Aging-Related Failures (ARFs) accurately. In this paper, permutation entropy (PE) is modified to Multidimensional Multi-scale Permutation Entropy (MMPE) as a novel aging indicator to detect performance anomalies, since MMPE is sensitive to dynamic state changes. An experiment is set on the distributed database system Voldemort, and MMPE is calculated based on the collected performance metrics during execution. Finally, based on MMPE, a failure prediction model using the machine learning method to reveal the anomalies is presented, which can predict failures with high accuracy.     

Preparation and Characterization of an Organic/Inorganic Composite Based on Ferrospinel with Poly(Methyl Methacrylate) and Polyaniline

A novel organic/inorganic composite based on LiNi–ferrospinel with poly(methyl methacrylate) (PMMA) and polyaniline (PANI), PANI/PMMA/LiNi_0.5Fe₂O₄ composite, was synthesized via a facile in-situ polymerization process. The structures of the resulting samples were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, and atomic force microscopy. The optical and thermal properties of the PANI/PMMA/LiNi_0.5Fe₂O₄ composite were studied by fluorescent spectroscopy and thermogravimetry analysis. It was indicated that the existence of LiNi_0.5Fe₂O₄ (LFNO) in the PANI/PMMA/LFNO composite resulted in changes in the fluorescence spectra. The as-obtained composite may have potential for electrical and electromagnetic applications in antistatic materials, electromagnetic shields, radar absorbers, and so forth.     

Conical bubble photoluminescence from rhodamine 6G in 1, 2-propanediol

A modified U-tube conical bubble sonoluminescence device is used to study the conical bubble photoluminescence. The spectra of conical bubble sonoluminescence at different concentrations of rhodamine 6G (Rh6G) solution in 1,2-propanediol have been measured. Results show that the sonoluminescence from the conical bubbles can directly excite Rh6G, which in turn can fluoresce. The light emission of this kind is referred to as conical bubble photoluminescence. The maximum of fluorescence spectral line intensity in the conical bubble photoluminescence has a red shift in relative to that of the standard photo-excited fluorescence, which is due to the higher self-absorption of Rh6G, and the spectral line of conical bubble photoluminescence is broadened in width compared with that of photo-excited fluorescence.     

Contracting on Average Random IFS with Repelling Fixed Point

We consider random iterated function systems which consist of strictly increasing and (not necessarily strictly) convex functions on a compact interval or on a half line. We assume that the system is contracting on average in a sense which is wide enough to permit the existence of a common fixpoint at which some functions of the system are expanding and perhaps none of them are contracting (see Fig. 1). We prove that the Hausdorff dimension of any of the possibly uncountably many invariant measures is smaller than or equal to the accumulated entropy divided by the Liapunov exponent. Mathematics Subject Classification. Primary 42A85 Secondary 11R06; 26A46; 26A30; 26A78; 28A80     

Diffusion tensor parameters and principal eigenvector coherence: Relation to b-value intervals and field strength

Diffusion-weighted MRI images acquired at b-value greater than 1000 s mm^− 2 measure the diffusion of a restricted pool of water molecules. High b-value images are accompanied by a reduction in signal-to-noise ratio (SNR) due to the application of large diffusion gradients. By fitting the diffusion tensor model to data acquired at incremental b-value intervals, we determined the effect of SNR on tensor parameters in normal human brains, in vivo. In addition, we also investigated the impact of field strength on the diffusion tensor model. Data were acquired at 1.5 and 3 T, at b-values 0, 1000, 2000 and 3000 s mm^− 2 in twenty diffusion-sensitised directions. Fractional anisotropy (FA), mean diffusivity (MD) and principal eigenvector coherence (κ) were calculated from diffusion tensors fitted between datasets with b-values 0–1000, 0–2000, 0–3000, 1000–2000 and 2000–3000 s mm^− 2. Field strength and b-value effects on diffusion parameters were analysed in white and grey matter regions of interest. Decreases in FA, κ and MD were found with increasing b-value in white matter. Univariate analysis showed a significant increase in FA with increasing field strength in highly organised white matter. These results suggest there are significant differences in diffusion parameters at 1.5 and 3 T and that the optimal results, in terms of the highest values of FA in white matter, are obtained at 3 T with a maximum b = 1000 s mm^− 2.