Studying metals and alloys with long term stable TG system

To study the corrosion resistance of metals and alloys, an analysis system needs to be able to simulate the harsh environments to which these materials are subjected. The system must also collect data from metal and alloy samples at elevated temperatures over long periods of time (typically days). Thermogravimetric analyzers (TGs) are well accepted systems for both corrosion studies and long-term elevated temperature studies. However, until now, TGs could conduct either corrosion studies or long-term studies, but not both. This paper presents a TG system specifically designed to satisfy the requirements of long-term corrosion resistance studies of metals and alloys.     

液相色谱指纹图谱在泽泻动态研究中的应用

应用指纹图谱技术，结合指标成分测定，采用高效液相色谱法，乙腈-水梯度洗脱，流速1．0mL／min，柱温20℃，色谱图光谱采集范围200～800nm，探讨了泽泻动态积累的规律。以泽泻标准对照药材为参照，用指标成分24-乙酰泽泻醇A和23-乙酰泽泻醇B进行了定位和测定，找出了21个共有峰，其中12号和20号峰分别为24-乙酰泽泻醇A和23-乙酰泽泻醇B。结果表明：泽泻样品指纹图谱及指标成分测定可为泽泻的最佳采收期提供科学依据。     

On maxima of partial samples in Gaussian sequences with pseudo-stationary trends

We consider a Gaussian stationary sequence added by a pseudo-stationary trend and prove a limit theorem for joint distribution of its maximum and maximum of its subsequence. Supported by RFFI grants 07-01-00077 and 06-01-00454. Published in Lietuvos Matematikos Rinkinys, Vol. 47, No. 1, pp. 58–67, January–March, 2007.     

增长型经济变量的趋势时间序列预测模型

针对增长型外汇储备时间序列变化复杂性的特点,可以建立确定性趋势的时间序列模型及包含单位根的随机趋势模型.实际计算显示,确定性趋势的时间序列模型具有较高的预测精度.     

Mathematical models of environmental forecasting

A technique of environmental forecasting with allowance for climate-related factors is proposed. For this purpose, a set of subspaces ranked in terms of disturbance scales is chosen by means of orthogonal decomposition from multidimensional multicomponent databases containing information on the functions of state that describe atmospheric processes for a long period. The leading part of subspaces that take into account climate-scale processes composes an informative basis for hydrodynamic background formation in calculating the forecast scenarios of changes in atmosphere quality. Calculated scenarios with estimates of atmosphere pollution in the Far East of Russia and at the adjacent territories of China and Korea are presented. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 3, pp. 152–163, May–June, 2007.     

真实利率波动对长期资产配置的影响(英文)

对于单期的投资者而言,无违约风险的固定收益证券被视为无风险资产.这是因为固定收益证券的收益率在投资的初期就能确定.然而在考虑长期的投资时,投资者可以调整资产配置,固定收益证券也将面临再投资的利率波动风险,因此不能再被视为无风险资产.本文在一类特殊的"习惯形成"效用函数的框架下讨论长期资产配置.在一系列为简化问题而作的假设之下,本文推导出了真实利率波动对风险资产配置权重的影响,并且为计算实际长期资产配置的最优比例提供了理论依据和算法.     

基于时间序列的网络安全态势预测方法的研究

互联网上每天充斥着大量入侵与攻击事件,已经严重威胁到网络安全,如何把握网络目前安全态势并预测其发展趋势已成为国内外网络应急响应的热点研究内容之一.根据网络安全事件发生的统计规律性,分别研究了基于时间序列的神经网络和灰色系统理论对未来一段时间内的安全事件数量进行预测的方法,并在此基础上对未来的安全态势进行评估,从而得知网络的整体安全运行状况,有效指导了管理员对网络安全的控制.     

安全生产事故的时间特征分析

基于我国安全生产事故快报数据,采用季节指数法对近年安全生产事故现状给出时间特征分析,确定出安全生产事故高发时间段.同时,给出总体的和死亡1人、3人以及4人的安全生产事故每年在每个时段平均事故总起数的概率分布模型.分析方法和结果有助于国家安全生产事故预防、控制和应对的监管工作.     

On a Test Statistic for Linear Trend

Let {W(s)} _s 0 be a standard Wiener process. The supremum of the squared Euclidian norm Y (t)², of the R²-valued process Y(t)=(1/t W(t), {12/t ³ int_{0 t} s dW (s)– {3/t} W(t)), t [, 1], is the asymptotic, large sample distribution, of a test statistic for a change point detection problem, of appearance of linear trend. We determine the asymptotic behavior P {sup _t [, 1] Y(t)² > u as u , of this statistic, for a fixed (0,1), and for a moving = (u) 0 at a suitable rate as u . The statistical interest of our results lie in their use as approximate test levels.     

The Role of Monosialoganglioside GM1 in LTP-Induction in Rat Hippocampal Slices

The effect of monosialoganglioside GM1 of different doses on the long-term potentiation (LTP) of synaptic transmission has been studied in the CA1 region of rat hippocampal slices, and the possible role that calcium ion and NMDA receptor play has also been investigated. The results reveal that larger magnitude of LTP is induced in hippocampal slices pre-incubated with GM1. The dose-response curve appears in diphase, and the largest magnitude of LTP has been obtained at the GM1 concentration of 50 mg/L in incubation ACSF. Moreover, the magnitude of LTP induced from the slices pre-incubated with GM1 at lower calcium ion concentration is similar to that obtained from the control slices at normal calcium ion concentration. Under higher calcium ion concentration, the enhancing effect of GM1 on LTP seems relatively feeble. After NMDA receptors were blocked, no enhancing effect of GM1 was observed. The mechanism of GM1 action on LTP is discussed.