Enhanced anti-sunward flow near local noon during a period of horizontal IMF and high solar wind velocity <Emphasis Type="Italic">V</Emphasis><Subscript><Emphasis Type="Italic">Y</Emphasis></Subscript>

It is believed that a southward interplanetary magnetic field (IMF) is mainly responsible for the energy input from solar wind into the magnetosphere. This paper presents an unusual case of strong anti-sunward plasma flow (up to 2 km/s) in the polar cap ionosphere and large cross-polar cap potential (CPCP) during a period of horizontal IMF (|B _Z | < 2 nT) observed by both ACE (at the L1 point) and Geotail (on the dusk flank of the magnetosheath). The CPCP is even higher than that under preceding B _Z ≈ −23 nT. Furthermore, GOES8 observed that the magnetosheath field turns northward as the anti-sunward plasma flow and CPCP start to increase, which implies that the magnetosheath field interacting with the Earth’s magnetopause has significantly rotated and differs from the IMF observed by ACE and Geotail. In accordance with previous theoretical work, we suggest that the magnetic field line draping produces a southward magnetosheath field and enhances anti-sunward plasma flow and the CPCP.     

Applying partial correlation method to analyzing the correlation between ionospheric NmF2 and height of isobaric level in the lower atmosphere

On the basis of a multiple linear regression model performed for ionospheric NmF2, partial correlation method is first applied to investigating the relation between NmF2 and h (the height of isobaric level) in the lower atmosphere over Wuhan, China during 1957―2004. The results show that partial correlation method can eliminate the influences of solar and geomagnetic activities as well as the seasonal varia- tion factors and reveal the true correlation between NmF2 and h in the lower atmosphere. A weak posi- tive correlation between NmF2 and h is found in the middle stratosphere. In addition, by comparing the partial correlation coefficients between NmF2 and its influence factors, we find that NmF2 is mainly affected by solar activity and the seasonal variation factors, and weakly affected by geomagnetic ac- tivity, but hardly affected by h in the lower atmosphere. The study suggests that partial correlation method is a helpful tool for investigating the correlation between ionospheric parameter and its influ- ence factors.     

制药工程专业本科生物理化学课程双语教学初探

为了适应社会需要,培养能与国际接轨的制药专业人才,我们在物理化学课中实行了双语教学,并对该模式在实践运用中的问题和实施方法进行了初步的探讨。     

Computationally efficient locality-aware interconnection topology for multi-processor system-on-chip (MP-SoC)

This paper evaluates the Triplet Based Architecture, TriBA – a new idea in chip multiprocessor architectures and a class of Direct Interconnection Network (DIN). TriBA consists of a 2D grid of small, programmable processing units, each physically connected to its three neighbors so that advantageous features of group locality can be fully and efficiently utilized. Any communication model can be well characterized by locality properties and, any topology has its intrinsic, structural, locality characteristics. We propose a new criterion in performance evaluation that is based on the concept of locality in an interconnection network, the “lower layer complete connect”. Our proposed criterion depicts how completely a processing node is connected to all its neighbors. TriBA is compared with 2D Mesh and Binary Tree as static interconnection network. The comparison / evaluation is enumerated from three orthogonal view points, viz., computational speed, physical layout and cost. Our analysis concludes that TriBA is computationally efficient interconnection strategy that exploits group locality in processing nodes.     

Development of a middle and low latitude theoretical ionospheric model and an observation system data assimilation experiment

On the basis of previous work, we develop a middle and low latitude theoretical ionospheric model in this paper, named Theoretical Ionospheric Model of the Earth in the Institute of Geology and Geophysics, Chinese Academy of Sciences （TIME-IGGCAS）. TIME-IGGCAS solves the equations of mass continuity, motion and energy of electron and ions self-consistently and uses an eccentric dipole field approximation to the Earth＇s magnetic field. We combine the Eulerian and Lagrangian approaches in the model and take account of the plasma ExB drift velocity. Calculation results reveal that the model is steady and credible and can reproduce most large-scale features of ionosphere. By using TIME-IGGCAS, we carried out an observation system data assimilation experiment. Assimilation results show that the ExB drift velocity can be accurately estimated by ingesting the observed foF2 and hmF2 into the model applying nonlinear least-square fit method. We suggest that this work is of great significance in the development of ionospheric data assimilation model to give better nowcast and forecast of ionosphere.     

流动电势法对L-谷氨酸水溶液结晶过程的表征

以流动电势法研究L-谷氨酸饱和水溶液的降温结晶过程,考察了溶液起始温度和酸度对结晶过程中流动电势(ν)-结晶器温度(t)曲线的影响。结果表明:起始温度为15℃的L-谷氨酸饱和溶液在较高酸度条件(pH3.5)下成核明显,25℃下等电点附近有成核能力,30℃下在不同酸度下均显示一定的成核能力;pH=2.5、pH=3.5的L-谷氨酸饱和溶液,只在起始温度15℃下可形成晶核;pH=3.0的饱和溶液在起始温度25和30℃下可有效地形成晶核。运用生长基元理论对此结晶过程进行了分析。     

Excel在创新分光光度分析新方法中的应用

针对当前多数学生在大学一年级学过计算机基础课后,在与化学有关的实验及毕业设计(论文)中不会应用计算机绘制实验结果图的情况,笔者以创建分光光度分析新方法中的各种影响因素(如吸收光谱,酸度或pH试验,试剂用量试验和标准曲线等)的条件优化为例,针对性地介绍利用Excel电子表格绘制实验结果图的具体方法,以便加强与化学化工相关专业大学生的计算机在化学实验、科学研究及毕业设计(论文)中的应用能力。     

Solar activity effects of the ionosphere: A brief review

Solar radiation, which varies over multiple temporal scales, modulates remarkably the evolution of the ionosphere. The solar activity dependence of the ionosphere is a key and fundamental issue in ionospheric physics, providing information essential to understanding the variations in the ionosphere and its processes. Selected recent studies on solar activity effects of the ionosphere are briefly reviewed in this report. This report focuses on (1) observations of solar irradiance at X-ray and extreme ultraviolet wavelengths and the outstanding problems of solar proxies, in the view of ionospheric studies, (2) new findings and improved representations of the features of the solar activity dependence of ionospheric key parameters and the corresponding physical processes, (3) possible phenomena in the ionosphere under extremely high and low solar activity conditions that are unique, as indicated by historical solar datasets and the deep solar minimum of solar cycle 23/24, and (4) statistical studies and model simulations of the ionosphere response to solar flares. The above-mentioned studies provide new clues for comprehensively explaining basic processes in the ionosphere and improving the prediction capability of ionospheric models and related applications.     

Correlation between ionospheric longitudinal harmonic components and upper atmospheric tides

There is strong correlation among the ionospheric longitudinal structures of wavenumber-3 (WN3), wavenumber-4 (WN4), and eastward-propagating diurnal tides with zonal wave numbers s = 2 and 3 (DE2 and DE3) in the upper atmosphere. The total electron content derived from the Global Ionospheric Maps of the Jet Propulsion Laboratory is used to deduce the latitudinally total electron content (ITEC) in the low-latitude ionosphere, and TIDE/TIMED observations are employed to obtain zonal and meridian winds of the mesopause and lower thermosphere. Through Fourier transformation, various ionospheric longitudinal harmonic components and tidal patterns are derived from the ionospheric and upper-atmospheric observations, and we compare the annual/inter-annual variations in ionospheric harmonic components WN3 and WN4 with those in atmospheric tides (DE2 and DE3). It is found that the annual and inter-annual variations in WN3 and WN4 are consistent with those in DE2 and DE3 zonal wind components respectively, while they are inconsistent with those in the meridian components. We then decompose the harmonic components into “tidal patterns”, finding that the “DE2” and “DE3” patterns are the main parts of WN3 and WN4 respectively. Their annual and inter-annual variations are similar to those of atmospheric tidal patterns (DE2 and DE3). Complex correlation results show that correlation between the ionospheric “DE2” in WN3 and the atmospheric tidal DE2 zonal wind component is quite strong in the Northern Hemisphere, while that between the ionospheric “DE3” in WN4 and the atmospheric tidal DE3 zonal wind component is much stronger at low latitudes. At the same time, the contribution of the meridian wind component is very weak. Above all, the atmospheric tidal DE2 and DE3 patterns are important factors of the ionospheric WN3 and WN4 structures.     

带有一种新佣金率的拍卖模型

提出了一种带有保留价及新的反比佣金率c=（1/k）√b（k为佣金率系数,b为成交价）的拍卖模型,这种反比佣金率更加符合实际。首先计算出第一价格拍卖和第二价格拍卖中投标者的均衡投标策略,然后计算出两种拍卖模式中拍卖参与各方的预期收益。结果表明,一级价格密闭式拍卖中投标者的均衡报价关于保留价及佣金率系数均递增,而二级价格密闭式拍卖中投标者的均衡报价关于佣金率系数递增、关于保留价递减。