Temporal kernel CCA and its application in multimodal neuronal data analysis

Data recorded from multiple sources sometimes exhibit non-instantaneous couplings. For simple data sets, cross-correlograms may reveal the coupling dynamics. But when dealing with high-dimensional multivariate data there is no such measure as the cross-correlogram. We propose a simple algorithm based on Kernel Canonical Correlation Analysis (kCCA) that computes a multivariate temporal filter which links one data modality to another one. The filters can be used to compute a multivariate extension of the cross-correlogram, the canonical correlogram, between data sources that have different dimensionalities and temporal resolutions. The canonical correlogram reflects the coupling dynamics between the two sources. The temporal filter reveals which features in the data give rise to these couplings and when they do so. We present results from simulations and neuroscientific experiments showing that tkCCA yields easily interpretable temporal filters and correlograms. In the experiments, we simultaneously performed electrode recordings and functional magnetic resonance imaging (fMRI) in primary visual cortex of the non-human primate. While electrode recordings reflect brain activity directly, fMRI provides only an indirect view of neural activity via the Blood Oxygen Level Dependent (BOLD) response. Thus it is crucial for our understanding and the interpretation of fMRI signals in general to relate them to direct measures of neural activity acquired with electrodes. The results computed by tkCCA confirm recent models of the hemodynamic response to neural activity and allow for a more detailed analysis of neurovascular coupling dynamics.     

基于S3C4510B的ARM开发平台

随着计算机技术、微电子技术和网络技术的迅速发展,嵌入式系统在各个领域得到了广泛的应用。ARM处理器是目前公认的业界领先的32位嵌入式RISC微处理器,已成为许多行业嵌入式解决方案的RISC标准。文章首先介绍了S3C2410B芯片的工作机制,然后介绍了基于S3C2410B芯片的ARM开发平台-S3C2410B开发板。该平台功能强大,适合用来作为开发高性能手持式以及便携式智能设备或终端。     

树立科学发展观开创工程硕士教育新局面

本文简要回顾了工程硕士教育的发展历程，阐述了树立科学发展观进一步开展工程硕士教育的重要性，从发展规模、培养质量、建立质量评估体系及加强宣传和国际合作等方面，对工程硕士教育的开展提出了自己的见解。     

纳米复合抗菌面料的研制及其抗菌性能

针对纳米抗菌材料使用单一纳米抗菌技术的不足，采用研制了不同抗菌机制和抗菌性能的抗菌剂组合起来的纳米抗菌技术。该技术研制的抗菌面料对金黄色葡萄球菌和致病性大肠杆菌等病菌(毒)具有良好的灭杀作用，可用于制作多种预防传染性疾病的防护用品。该工作为今后研制具有高效、快速、广谱杀菌作用的纳米抗菌材料提供了一个新思路。     

碳对铁及其合金超细微粒氧化特征的影响

采用ＣＯ２激光诱导Ｆｅ（ＣＯ）５－Ｃ２Ｈ４－ＮＨ３的气相分解反应制备了Ｆｅ、Ｆｅ－Ｎ和Ｆｅ－Ｃ－Ｎ超细微粒（微粒直径小于１００ｎｍ）,用透射电子显微镜、Ｘ光衍射、Ｏ／Ｎ和Ｃ／Ｓ测试仪及振动样品磁强计等研究了微粒的结构、表面形态、表面氧的状态及磁性能等;探讨了碳对微粒的氧化特征,特别是对微粒表面氧的形态及其磁性能的影响。结果表明,微粒表面氧的状态可分为吸附态和化合态,并且二者的含量随着微粒的种类不同而变化,碳对微粒表面氧的存在状态、微粒的氧化状况及磁性能具有决定性的影响     

Some blind FRESH equalization algorithms with anti-interference capabilities

Some novel blind FREquency-SHift （FRESH） equalizer algorithms are proposed for the equalization of Finite Impulse Response （FIR） single channel with anti-interference capabilities. These algorithms based on FRESH filter can work well without any training sequence. Simulation results show that the equalizer algorithms can effectively reject many types of interferences and the performances of these new equalizer algorithms are superior to the conventional equalizer algorithms.     

A class of band-limited chip waveforms for DS-CDMA systems

In Direct Sequence Code Division Multiple Access （DS-CDMA） systems, the chip waveform affects the implementation, system bandwidth, envelope uniformity, eye pattern and Multiple user Access Interference （MAI）. In this paper, based on an elementary density function of a second order polynomial, a class of second order continuity pulses is proposed. From this class of pulses, we can find some members having faster decaying rate, bigger eye opening, more uniform envelope and stronger anti-MAI capability than the Nyquist waveform. The normalized-bandwidth-pulseshape-factor product, the decaying rate of the tail of the time waveform, the opening of the eye diagram, and the envelope uniformity of the second order continuity pulses are addressed in the paper that provide the basic information for the selection of the chip pulse for CDMA systems.     

First successful fabrication of high-performance all-refractory-metal (Ta-Au) GaAs FET using very highly doped N+-layers and nonalloyed ohmic contacts

An all-refractory-metal GaAs MESFET (ARFET) making use of a Ta Schottky barrier with a thick gold overlayer for the source, gate and drain, and very highly doped N+-layers (2x1019 cm-3) to achieve low-resistivity nonalloyed ohmic contacts, has been successfully fabricated. These have a 400 ?m gate periphery and 0.6 ?m gate length and measured an associated gain of 10.22 dB and a noise figure of 2.14 dB at 8 GHz. The ARFETs were fabricated on epitaxial layers grown by MBE. Only one mask was used to simultaneously define source, gate and drain regions via a plasma dry-etch technique.     

焉耆盆地原油物理化学特征及油源对比研究

在焉耆盆地侏罗系三工河组和八道湾组均发现原油,目前关于侏罗系产层原油的油源问题存在不同的认识。对研究区原油的物理、化学性质进行系统的研究,认为侏罗系三工河组和八道湾组原油不仅在物理性质上有一定的差别,而且在地球化学组成及生物标记化合物上也有一定的差异,应具有不同的来源。侏罗系三工河组原油属于典型腐殖型干酪根成因,而侏罗系八道湾组原油除了具有腐殖型干酪根成因的某些特征外,还具有湖相泥岩生烃的特点。通过原油与各类源岩生物标志物进一步对比分析发现,侏罗系三工河组原油与西山窑、三工河组烃源岩及石炭系、三叠系烃源岩地球化学特征均存在明显差异,与侏罗系八道湾组烃源岩对比性较好。侏罗系八道湾组原油与八道湾组、三叠系源岩有一定相似性,因此认为八道湾组源岩为其主要源岩,三叠系源岩也有一定的贡献。目前勘探生产主要以八道湾组烃源岩为目标,下一步应加强对三叠系烃源岩贡献区带的勘探部署。     

EXTRACTION OF LINCOMYCIN WITH LONG-CHAIN ALCOHOLS AS SOLVENT

ABSTRACT

The extraction of lincomycin with long-chain alcohols as solvent was studied. The experimental results indicated that the power of n-alkyl alcohols for the extraction of lincomycin depends mainly on the molarity of alcohols in solvent used. For alcohols with short carbon chain, the steric hindrance of alkyl groups in alcohols with different structure has only little influence on the extraction of lincomycin. The chemistry of extraction of lincomycin with alcohols as solvent was discussed.