BNs-OLS-SARIMA对城市短时交通流的预测*

通过在目标路口构建贝叶斯交通网（BNs）,并对与此交通网相关的交通流建立非平稳季节（SARIMA）模型,采用最小二乘法（OLS）取得相应模型的最佳权重组合,对缺失数据下的城市道路短时交通流进行预测。使用重庆市某路口的交通流数据对模型进行检测,通过多种预测指标对结果进行对比分析,结果表明BNs-OLS-SARIMA把交通流的网络结构与其周期性结合在一起,对短时交通流有良好的预测效果。     

基于全距置换的数字图像加密

全距置换可以打乱数据的位置,同时又能使元素间距离的所有可能性都出现。所以从换位角度看,全距置换具有良好的密码学性质。将全距置换引入到图像加密的领域,提出了两种利用全距置换对数字图像进行加密的算法。     

基于运动投影周期性特征的人体目标检测方法

针对摄像机较远距离拍摄目标的情形,提出一种利用人体行走时的投影周期性特征进行人体目标检测的方法,首先通过运动分割获取每一帧的运动目标,然后通过计算运动目标的投影相似性对目标进行检测。为了简化计算,利用Hausdorff距离对运动目标的投影进行相似性计算,同时为减少存储空间,利用码书作为存储相似性特征的数据结构。     

On Nonlinear Control Systems with Multiple Time Scales

An order reduction procedure for nonlinear control systems with multiple time scales is introduced. A limit system for the slowest motion describing the situation that all singular perturbation parameters vanish is constructed. For this purpose a refined two-scale averaging method is used in a way that allows a re-iteration. For vanishing control range the results reduce to the well-known Tychonoff theorem on order reduction for singularly perturbed ODEs.     

Two-dimensionally quantized friction observed with two-dimensional frictional force microscope

Using a two-dimensional frictional force microscope, we studied the two-dimensional nature of the atomic scale friction between a Si₃N₄ sharp tip and a cleaved graphite surface, which is composed of only C atoms and is a good conductor. As a result, we observed the two-dimensionally quantized friction with the lattice periodicity of the graphite surface, similarly to mica, MoS₂ and NaF surfaces. Thus quantized friction occurs at material surfaces which are composed of not only some elements but also of a single element, and the quantized friction does not depend on the conductivity of the surface.     

FORECASTING GLOBAL ICE VOLUME

Abstract. Forecasts and associated probability limits of total ice volume for the next 100 000 years are found based upon a historical record of 440 000 years of oxygen-18 from deep sea cores. The forecasts are found using two different time series models, one based on the assumption that ice volume contains deterministic sinusoids, and one assuming that the record contains 'disturbed periodicities', i.e. the sinusoids do not have the same cycle length and amplitude from one cycle to another. The results for the two models are seen to be very similar, with both predicting a small probability for a future ice volume event to be as large as the last ice age, which was one of the largest glaciations of the last 2 million years.     

Atomic Model for 3-Dimensional Periodic Structure and 12-fold Rotational Symmetry

A VNi atomic model for 3D periodic structure is posed based on T polyhedrons which are introduced. The fourier transform patterns of the atomic model may explain the 12-fold symmetry in electron diffraction patterns of V60Ni40 alloy. This is the first satisfactory explanation since the V60Ni40 alloy has been reported.     

城市燃气小时用气负荷周期性研究

将频谱分析技术用于城市燃气小时负荷周期性研究，小时负荷不仅有主周期，还有隐含的次周期。     

Some structural complexities of time-varying sequential machines

Sequential machines with time-variant logic and memory elements are investigated in this paper. Our major efforts are exerted toward considering the isomorphism, minimality, periodicity, time invariance, and convertibility of time-varying sequential machines with an arbitrary set of internal states. It turns out that, if an infinite-state time-varying sequential machine is finite-state realizable, it must eventually bear some sort of a periodic structure and satisfy a time-invariance property on an extended time basis.     

The problem of obesity: fundamental concepts of energy metabolism gone awry.

The growing prevalence and complex issues related to obesity continue to draw the interest and concern of health researchers and practitioners. This review summarizes pertinent background information on the multiple factors involved in the causes of obesity. Factors such as percentage of body fat, upper- vs. lower-body obesity, family history, past dieting history, and underlying medical conditions should be assessed on an individual basis and applied in the development of successful weight-reducing strategies. The recommended approach to nonpharmacologic intervention for weight loss is to first educate individuals about fat storage and energy balance and then focus on the development of positive behavioral skills such as wise food selections, favorable eating patterns, and regular physical activity. Although preventive measures such as positive eating patterns and exercise habits are ideally acquired in childhood and adolescence, successful weight management can still be achieved in adulthood. The information presented in the following sections provides clinicians with essential material to assist individuals in developing realistic goals at the outset of a weight-control program.