宽谱段光纤光谱仪

为满足野外现场矿物分析、遥感地面验证光谱分析等的需要,研制了实现光谱覆盖范围在400～2 500 nm的宽谱段光纤光谱仪,介绍了仪器研制过程中的光学、机械与电子学设计。光学系统采用了光栅分光的水平反射式光路,对于不同的光谱探测谱段,采用了三路线阵探测器在光谱面的3个方向立体交错放置进行探测;用CPLD(complex programmable logic device)实现对三路线阵光电器件时序逻辑信号的发生与驱动;采用14位高速ADC进行数模转换;采用USB2.0实现通讯。仪器体积小、光谱分辨率高、信号质量和测量速度等方面均达到了满意效果,测试结果表明,仪器实现了宽谱测量,光谱数据理想。     

如何利用NOMA2.0实现话务高峰时的动态话务控制

话务控制的目标是在最有效利用网络资源的前提下最大限度地疏通呼叫。话务控制有利于改善业务质量及增加网络收益。本文主要结合2000年9月高校刚开学时对200,201字冠的高话务冲击实施动态话务控制进行详细介绍。     

Shock and traveling wave phenomena on an externally damped, non-linear string

We examine the propagation of shocks and traveling wave phenomena on a one-dimensional string that is executing finite-amplitude, transverse vibrations in a resisting medium. As part of our study, we develop an approach that allows us to describe, albeit approximately, the evolution and propagation of a shock front using analytical methods. In addition, exact traveling wave solutions, one of which involves the Lambert W-function, of the string's equation of motion are determined and analyzed. Lastly, a possible new form of the solution to the linearized problem is presented and extensions and other applications of the present work are briefly discussed.     

First separation and characterization of cis and trans 1,2-bisaryloxy perfluorocyclobutanes

4-Bromotrifluorovinyloxybenzene (4-Br-TFVE) undergoes cyclodimerization upon heating at 150 °C affording cis and trans isomers of 1,2-bis(4-bromophenoxy)hexafluorocylcobutane. Stereoisomers were separated by selective crystallization, confirmed by single crystal X-ray, and further characterized by NMR. Remarkable difference in the solid state structures include aryl to aryl dihedral angles of 12° for the trans isomer and 88° for the cis isomer. Polymers containing roughly equal amounts of cis and trans fused perfluorocyclobutyl (PFCB) rings should be expected to have low crystallinity due to the marked difference in the two unit cells as is observed.     

HDMI2.0接口FEC纠错模块设计

针对HDMI2.0中继器在传输数据的过程中数据因干扰会发生错误的问题,提出了采用前向纠错技术(FEC)来纠正控制周期数据错误而导致的错误视频和音频数据的方案,给出了FEC和HDMI2.0协议相结合的具体过程,实现了基于HDMI2.0接口的数据纠错模块的设计.在Cadence平台下,编写了可综合的Verilog代码实现了电路的设计,并用科学的测试方法对数据纠错模块进行了测试验证.验证结果表明:数据纠错模块和HDMI2.0接口有机地结合在一起,有效纠正了HDMI2.0中继器在数据传输过程中产生的错误,增强了数据传输的可靠性并提高了视听效果.     

H nuclear magnetic resonance spectroscopy analysis for simultaneous determination of levodopa, carbidopa and methyldopa in human serum and pharmaceutical formulations

A method utilizing NMR spectroscopy has been developed to confirm the identity and quantity of levodopa, carbidopa and methyldopa in human serum and pharmaceutical preparations. The method is based on 500 MHz proton NMR spectra of individual catecholamine molecules. Qualitative and quantitative analyses are based on resonance characteristics of the functional groups present in their structures and the integral ratio of selected signals belonging to different compounds with respect to those of an internal standard, respectively. Experiments are performed to validate the quantitative NMR method, and the linearity and reproducibility of the proposed method are verified. The detection limit of the proposed method was estimated as 4.2, 1.7 and 1.6  μg ml⁻¹ for levodopa, carbidopa and methyldopa, respectively. The recovery studies performed on human serum samples ranged from about 82-96% with relative standard deviations of <4%. The method was also applied successfully to the determination of each active compound in real pharmaceutical samples, and compared with the results obtained by the reference methods. The method is rapid, precise, accurate, and suitable for routine analyses.     

Understanding the role of digital commons in the web; The making of HTML5

The last version of Web’s hypertext standard has been developed from 2004 to 2014. During this era, HTML5 has experienced different crossroads due to the variety of motivations and needs that the main stakeholders interested in its development had. On October 2014, the standard got official by the W3C and closed a period of uncertainty around the future of the Web but at the same time, this agreement also introduced a major change in the own conception of the hypertext’s standard. In this paper we review the current status of digital commons on the Web and the development of HTML5. We also confront this analysis with several semi-structured interviews carried out with different experts in web development that represent at the same time different players of Web’s value chain.We argue that the development of HTML5 represents a new digital commons that prevented the proliferation of proprietary software that took place during the “Web 2.0” period. We claim that the World Wide Web promotes the development of new digital commons due to its own basis as a non-proprietary socio-technological platform. We also conclude that the development of standards and non-proprietary digital technologies is of outmost importance for the future of web business models that are fueled by major digital players.     

基于Web2.0环境下的数字音乐共享机制研究

随着越来越多新科技的加入,数字音乐在其发展中在遇到新机遇的同时也会遇到新的问题。处于Web2.0环境下的数字音乐,它有着以P2P技术和C/S技术为基础的用户和客户共享机制,而我们只有处理好在这两种机制下提出的五项基本要素,才可以合理更好的实现数字音乐的共享。     

基于DSP和USB2．0的高速实时数据采集与分析系统

介绍了一种适用性较广的数据采集与分析系统的设计方案，为保证系统的高速和实时性，采用了CPLD＋D即＋UBS2．0的新方案。通过开发新的主机应用程序和DSP算法程序，该系统可用在信号分析、图像处理、语音处理等很多方面，具有良好的扩展性。     

AMBA 2.0总线IP核的设计与实现

文章采用Top—Down的方法设计了AMBA2．0总线IP核，它包括AHB和APB两个子IP核。所有AMBA结构模块均实现了RTL级建模，对其中较复杂的仲裁器和AHB／APB桥模块给出了详细的描述。该IP完成了FPGA的验证，最高频率为53．6MHz。在ASIC0．18μm标准单元库下对该IP进行综合与优化，最高频率可以达到150MHz。