基于LVDS的高速数据传输技术实现

为实现高速数据采集系统中多路串行数据的内部传输,解决常规时钟同步所带来的时钟资源不足的问题,笔者采用异步通信方式在数据接收端设计了一种基于空间过采样的时钟数据恢复系统,通过介绍基于LVDS的高速数据传输技术,提出了基于过采样法的时钟恢复思想、原理解决方法,分析了时钟数据恢复过程,数据传输测试实验结果显示该系统可实现高速串行数据传输,为基于FPGA的高速数据传输,尤其是为多通道大数据量传输提供了可供参考的解决方案。     

基于FPGA的高速数据传输方案设计与实现

为解决目前信号处理系统中数据传输的瓶颈问题,设计并实现了一种基于可编程门阵列(field programmable gate array,FPGA)的高速实时数据传输方案。该方案借助Xilinx FPGA的ChipSync技术,稳定地完成了数据的串化/解串,以及通信链路相对延迟的精确测量和调整。同时,利用提出的数据传输同步方法-系统同步和串行低压差分信号(low-voltage differential signaling,LVDS)总线技术实现板卡间大量数据的高速传送,有效地保证了多通道传输的同步性和可靠性,并大大降低了系统互联的复杂度和系统成本。     

基于FPGA的高速数据传输方案设计与实现

为解决目前信号处理系统中数据传输的瓶颈问题,设计并实现了一种基于可编程门阵列(field programma-ble gate array,FPGA)的高速实时数据传输方案.该方案借助Xilinx FPGA的ChipSync技术,稳定地完成了数据的串化/解串,以及通信链路相对延迟的精确测量和调整.同时,利用提出的数据传输同步方法一系统同步和串行低压差分信号(low-voltage differential signaling,LVDS)总线技术实现板卡间大量数据的高速传送,有效地保证了多通道传输的同步性和可靠性,并大大降低了系统互联的复杂度和系统成本.     

LVDS技术在数字信号处理实验系统中的应用

本文讨论低电压差分信号(LVDS)技术,结合 LVDS 数据传输卡的设计制作,介绍 LVDS技术在信号处理实验系统中的应用。     

基于卫星通信的空中爆炸冲击波威力测试系统

针对空中爆炸冲击波威力测试中测试环境恶劣、设备无法监控、数据回收困难等问题,基于空中爆炸冲击波力学特性和传播规律,综合运用存储测试技术和卫星通信技术,研究一种卫星方式通信的冲击波威力测试系统,给出了系统设计方案和实现方法.测试系统能在任意环境下完成任意距离的无线数据传输,实现测试设备的无线远程监控和试验数据快速回传,节省了大量的人力和时间成本,且有效提升测试试验的可靠性与稳定性.对测试系统在网络调试助手模拟和实爆测试两种状态下开展测试试验,并将测试结果与Henrych公式计算结果进行对比分析,结果表明研制的系统测试数据准确、传输可靠性高,满足复杂恶劣环境下装药冲击波超压实际测试需求.      

基于LVDS的高速远程图像采集存储系统

设计了一种基于LVDS总线的以NAND型FLASH为存储核心的高速远程图像采集存储系统,实现了高速遥测图像数据的采集及实时存储。重点研究了高速A/D采集技术、LVDS高速数据传输技术,保证了远程图像数据的有效接收,同时采用双片选交替双平面页编程方式,将29.85MB/s的两路高速实时图像数据存储于FLASH芯片中。着重从系统硬件电路和逻辑时序两方面进行研究设计,经大量测试表明存储器性能稳定,存储可靠,可以完整记录两路高速遥测图像数据,满足设计要求。     

基于LVDS的高速数据传输装置的设计

针对弹载数据记录设备和地面测试设备之间大量数据高速传输的问题,本文提出了应用低电压差分信号(LVDS)接口器件和FPGA结合的设计方案实现数据高速远距离传输。详细介绍了LVDS的基本工作原理,并对该装置软硬件设计以及各个模块功能的具体实现进行讨论和分析。该装置已成功应用某项目中,具有较高的可靠性、通用性。     

遥操作无人水下航行器图像数据传输设计

分析了遥操作无人水下航行器数据通信结构。针对图像数据长时间占据以太网,致使航行器控制系统其它重要数据无法得以及时传输的问题,提出一种图像数据传输方法。根据不同数据的重要性、数据量等特点,设计了基于TCP/IP的应用层协议和不同网络协议的数据传输软件。通过图像数据分割传输,保证控制数据传输的实时性,提高数据传输的可靠性。     

基于LVDS总线的数字信号源设计与实现

针对如何实现高速数据传输的问题,设计了基于LVDS总线的数字信号源。LVDS是一种高速传输技术,利用低压差分信号进行数据传输,具有低功耗、低误码率、低串扰和低辐射的特点。设计以FPGA作为控制核心,并以DS92LV18实现LVDS信号的传输。试验表明采用LVDS技术作为功能卡之间的数据传输方式,可以很好的实现卡之间的高速数据传输。该信号源可实现输出PCM数字信号,输出的信号由上位机软件设定。     

基于CAN总线的智能照明控制系统的设计和实现

针对传统的灯光照明设备控制存在通信距离短、数据传输速率慢、误码率高、可靠性差等问题,提出了一种基于CAN总线的智能照明控制系统。该系统采用CAN环形冗余网络,给出了系统的总体结构以及控制模块硬件设计方案,并简单介绍了网络通讯和控制软件设计及实现过程。该系统功能强、投资少、可靠性高,便于扩展,有着广阔的应用前景。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.