Design and implementation of 1 GHz high speed data acquisition system

With the development of current electronic technology, numerous high-speed data acquisition systems provide a variety of potential benefits. This article describes a high-speed data acquisition system which consists of ECL logic and TTL logic devices, samples and stores data with a 1 GHz clock. This system is accomplished easily and works stably. A performance test of this system has been undertaken and the results show that the effective number of bits （ENOB） is more than 6.5 bits.

Discuss on High Speed Data Acquisition and Signal Processing

In order to realize the high speed data acquisition and fast Fourier analysis, the paper put forward a kind of high speed data acquisition and analysis system based on FPGA, the system uses Cyclone series FPGA with high-speed A/D converter, and use the fast Fourier custom analysis nucleation of Altera company, using the standard TCP/IP protocol communication with PC, match up the master machine based on Matlab GUI analysis software. We experiment high speed data acquisition and fast Fourier analysis for a plurality of groups of high frequency analog signals, at the same time the results display on the computer. The experimental results validate the fast Fourier analysis theory, and has realized the low cost, high performance data acquisition and analysis of the complete system design.

High-speed broadband data acquisition system based on FPGA

A field-programmable gate array(FPGA)based high-speed broadband data acquisition system is designed.The system has a dual channel simultaneous acquisition function.The maximum sampling rate is 500 MSa/s and bandwidth is200 MHz,which solves the large bandwidth,high-speed signal acquisition and processing problems.At present,the data acquisition system is successfully used in broadband receiver test systems.

Evaluation on monthly sea surface wind speed of four reanalysis data sets over the China seas after 1988

This study investigates the long-term changes of monthly sea surface wind speeds over the China seas from 1988 to 2015. The 10-meter wind speeds products from four major global reanalysis datasets with high resolution are used: Cross-Calibrated Multi-Platform data set(CCMP), NCEP climate forecast system reanalysis data set(CFSR),ERA-interim reanalysis data set(ERA-int) and Japanese 55-year reanalysis data set(JRA55). The monthly sea surface wind speeds of four major reanalysis data sets have been investigated through comparisons with the longterm and homogeneous observation wind speeds data recorded at ten stations. The results reveal that(1) the wind speeds bias of CCMP, CFSR, ERA-int and JRA55 are 0.91 m/s, 1.22 m/s, 0.62 m/s and 0.22 m/s, respectively.The wind speeds RMSE of CCMP, CFSR, ERA-int and JRA55 are 1.38 m/s, 1.59 m/s, 1.01 m/s and 0.96 m/s,respectively;(2) JRA55 and ERA-int provides a realistic representation of monthly wind speeds, while CCMP and CFSR tend to overestimate observed wind speeds. And all the four data sets tend to underestimate observed wind speeds in Bohai Sea and Yellow Sea;(3) Comparing the annual wind speeds trends between observation and the four data sets at ten stations for 1988-1997, 1988–2007 and 1988–2015, the result show that ERA-int is superior to represent homogeneity monthly wind speeds over the China seaes.

Using Anonymous Connected Vehicle Data to Evaluate Impact of Speed Feedback Displays, Speed Limit Signs and Roadway Features on Interstate Work Zones Speeds

Annually, there are over 120,000 crashes in work zones in the United States. High speeds in construction zones are a well-documented risk factor that increases the frequency and severity of crashes. This study used connected vehicle data to evaluate the spatial and temporal impact that regulatory signs, speed feedback displays, and construction site geometry had on vehicle speed. Over 27,000 unique trips over 2 weeks on a 15-mile interstate construction work zone near Lebanon, IN were analyzed. Spatial analysis over a 0.2-mi segment before and after the posted speed limit signs showed that the regulatory signs had no statistical impact on reducing speeds. A before/after analysis was also conducted to study the impact of radar-based speed feedback that displays the motorists’ speed on a sign below a regulatory speed limit sign. Results showed a maximum drop in median speeds of approximately 5 mph. Speeds greater than 15 mph above the speed limit dropped by 10% - 15%. The reduction in speeds began approximately 1000 feet ahead of the sign and results were found to be statistically significant. The analysis also revealed that larger speed drops inside the work zone were due to geometric constraints that required additional driver workloads, especially during shoulder width changes and lane shifts. The results from this study will be helpful for agencies to understand driver behavior in the work zones and to identify proper speed limit compliance techniques that significantly reduce driver speeds in and around work zones.

Reconstructing Sound Speed Profiles with Sea Surface Data

Ocean sound speed profile(SSP) is the key factor affecting acoustic propagation. The acquisition of SSPsin real time with high precision is meaningful for underwater activities. By means of the remote sensing method, thesea surface data could be obtained in near-real time. Typically, the subsurface fields are correlated with the sea surfaceparameters. Thus, the SSPs could be obtained by means of satellite remote sensing. In this paper, the history as wellas the current research over the reconstruction of subsurface fields by means of sea surface data is introduced. Thentwo methods to reconstruct the SSPs with sea surface data, including the linear regression method using the empiricalorthogonal function, and the self-organizing method based on the big data theory, are described in detail in the paper.

Using Connected Truck Trajectory Data to Compare Speeds in States with and without Differential Truck Speeds

Historically, researchers and practitioners have utilized spot speeds and microscopic simulation methodologies to evaluate the operational impact of differential or uniform speed limits for trucks and passenger vehicles. This paper presents a methodology that uses connected truck data to develop a statistical characterization of both passenger car and truck speeds. These techniques were applied to three adjacent states, Illinois, Indiana and Ohio. Illinois and Ohio have 70 mph speed limits for both trucks and cars. Indiana has a differential speed limit for heavy trucks (65 mph) and passenger cars (70 mph). The statistical distribution of truck speeds was then compared among Illinois, Indiana and Ohio. These speeds were derived from over 8 million connected truck records traveling along Interstate 70 in Illinois, Indiana and Ohio during a one-week period from May 8-14, 2022. Statistical test results over selected 20-mile sections in each state showed that median truck speeds in Indiana with its differential speed limit of 65 mph were only 1 - 2 mph lesser than the neighboring states of Illinois and Ohio who observe a uniform speed limit of 70 mph for all traffic.

EXISTENCE TIME FOR SOLUTIONS OFSEMILINEAR DIFFERENT SPEED KLEIN-GORDONSYSTEM WITH WEAK DECAY DATA IN 1D

A -4/3|log |-2 result is obtained for the existence time of solutions of semi- linear different speed Klein-Gordon system in one space dimension for weakly decaying Cauchy data, of size , in certain circumstances of nonlinearity.

Floating Car Data Based Nonparametric Regression Model for Short-Term Travel Speed Prediction

A K-nearest neighbor （K-NN） based nonparametric regression model was proposed to predict travel speed for Beijing expressway. By using the historical traffic data collected from the detectors in Beijing expressways, a specically designed database was developed via the processes including data filtering, wavelet analysis and clustering. The relativity based weighted Euclidean distance was used as the distance metric to identify the K groups of nearest data series. Then, a K-NN nonparametric regression model was built to predict the average travel speeds up to 6 min into the future. Several randomly selected travel speed data series, collected from the floating car data （FCD） system, were used to validate the model. The results indicate that using the FCD, the model can predict average travel speeds with an accuracy of above 90%, and hence is feasible and effective.

高速数传Gardner开环算法设计与分析

针对特定飞行器高速数传应用场景下的定时同步问题,分析了传统星地高速数传解调器符号定时同步设计的局限性,通过分析经典的O&M前馈符号定时同步算法,结合当前特定高速数传应用场景的特点,确定了符号定时同步算法设计的依据及设计要点,推导并设计了一种高速数传Gardner开环符号定时同步算法,根据仿真结果从不同角度对算法进行了进一步优化设计,以满足实际应用需求。在传统星地高速数传解调器符号定时同步实现原理基础上,给出了应用高速数传Gardner开环算法的符号定时同步实现原理。

一级干线公路的Panel Data限速模型

为使限速值的确定更为客观,避免以往仅以85%位速度作为限速主要依据所存在的缺陷,在剖析合理限速与运行速度、道路特征等约束条件之间所存在逻辑关系的基础上,根据百分位速度与其他限速影响因素所构成变量的数据结构与Panel Data结构的相似性,引入Panel Data相关建模方法来构建限速与百分位速度等影响因素之间的理论模型。采用逐步回归法与最小二乘虚拟变量相结合的方法来求解最优时点固定效应模型表达式,应用F检验或Hausman检验结果确定Panel Data模型类型及具体表达式,最终确定一级干线公路小型车限速的主要影响因素依次为行人干扰、地形、纵坡、百分位速度,大型车限速的主要影响因素依次为地形、纵坡、行人干扰、出入口密度。最后,应用统计软件分别对一级干线公路大、小型车Panel Data限速模型残差有效性进行检验,结果表明所建模型误差均在±10 km/h之内,说明所提出的限速确定方法在实际应用中具备一定的可行性。

铁路施工中的智能监测技术及其在高铁项目中的应用

随着现代铁路建设规模的不断扩大和技术要求的提高,智能监测技术在铁路施工中的应用日益广泛。文章探讨了智能监测技术的基本原理及其在高铁项目中的实际应用,通过案例分析展示了该技术在施工过程中的显著优势。通过传感器、图像与视频监控、大数据分析等多种技术手段,智能监测技术不仅提高了施工精度与效率,还显著提升了安全保障水平,降低了工程风险。文章结合多个高铁建设项目,详细分析了这些技术在实际施工中的具体实施及其产生的效果,并提出了未来在铁路建设领域智能监测技术的发展方向。

智能高速铁路“模数驱动、轴面协同”理论研究及应用

当前围绕中国国家铁路集团有限公司发布的智能高速铁路体系架构1.0内容,国内多条新建高速铁路线路积极开展技术创新,并投入到实际工程应用中。为进一步推进中国高速铁路智能化建设,从智能高速铁路建设发展运营宏观层面,以智能高速铁路多专业全要素为研究内容,以整体综合能效为目标,提出“模数驱动、轴面协同”的智能高速铁路复杂巨系统工程管理理论,设计包含多专业协同、需求为中心、与外部环境互动、全生命周期动态最优等多种要素在内的系统最优化方法,形成模数一体化驱动、全生命周期协同、全要素管理的系统管理机制,构建基于“模数一体、轴面协同”的系统总体效能最优化模型,为智能高速铁路设计、建造、运营全生命周期管理提供理论和技术指导。同时,分析福厦高速铁路在建设过程中在“模数驱动、轴面协同”理论指导下构建的业务应用体系架构,总结最新的实践应用成果,为大量既有运营高速铁路的智能化升级提供指导和借鉴,以提高国内整个高速铁路网的智能化水平。

面向医用高精度虚拟现实云平台的高速数据传输技术

现有实时医疗数据传输模型易发生丢帧、时延高等问题,文中基于深度强化学习提出了一种用于医疗云平台的高速数据传输模型。针对数据排队过程中的拥堵现象,算法对排队时延、优先权、服务质量指标以及系统容错率进行计算,得到任务的紧急程度,提升了关键任务的执行效率。通过深度强化学习模型对数据进行训练,并利用紧急程度对Q网络参数进行不断更新,得到任务执行的排队顺序,进而优化整个平台的网络时延。在对比实验测试中,所提算法的时延、速率和吞吐量等指标均为最优,证明其能够在低时延的状态下稳定可靠地传输数据。

A Storage Architecture for High Speed Signal Processing: Embedding RAID 0 on FPGA

The article proposes a new architecture based on RAID 0 tech in computer science for signal processing field to store high speed data. It is composed of SSD driven by FPGA, called SSD-based RAID on FPGA. This new architecture features high storage rate, mass capacity and small volume, and it is an efficient solution to store high speed data. The article describes the construction of SRF in details, and shows the test result of a demo system based on the architecture.

Improvements of the Computerized Data Acquisition System for 25MWt Experimental Facility of Coal-fired MHD Generator

This paper introduces the design and development of a new computerized data acquisition system for the coal fired magnetohydrodynamical (MHD) electrical power generation experiments. Compared to the previous system, it has a higher sampling rate and an improved simultaneity performance. It also improves the data collection method and sensor design for the measurement of Faraday voltages and Faraday currents. The system has been successfully used in many regular MHD generator tests. It provides an excellent base for the future research and development of the Coal fired MHD electrical power generation.

基于LSTM-Attention的高速公路短时速度预测方法研究

作为智能交通系统的重要组成部分,高速公路短时速度预测可为交通管理者提供动态调控依据,以提高城市交通系统运行效率。针对G92杭州湾环线高速公路ETC门架数据,进行分路段细化拆分与10 min级颗粒度归集;为解决统计学模型对波动性数据特征提取不足与RNN等模型存在的梯度消失问题,提出一种基于长短期记忆网络(LSTM)算法模型与Attention机制相结合的高速公路短时速度预测模型,其中,LSTM模型具有在捕获时间序列数据长期依赖关系捕捉和数据特征提取的优势,Attention机制的引入又可使时间序列在数据处理时更加注重关键信息,从而实现高速公路常规环境下短时通行状况的有效预测。

Analysis and Impact of Surface Acoustic Wave Filter in-Band Ripple on Testing and Measurement of High Data Rate Communications

In this paper, we present a background and theory of the effect of Surface Acoustic Wave (SAW) Filter Module (SFM) in-band ripple on high data rate communications parameters such as the Error Vector Magnitude (EVM). In addition, we present analyses and statements for the choice of unbalanced S-parameters set of the SFM over balanced S-parameters set of the SFM in measurements and Agilent’s Advance Design System (ADS) Ptolemy simulations. A test and measurement setup using Agilent’s equipment will be presented.

Transportation Infrastructure and Productivity Growth:Effects of Railway Speed-Up on Firm's TFP in China

Improvement of transportation infrastructure quality will lead to more sufficient market competition and promote the flow of resources with greater efficiency. This paper considers China's railway speed-up in 2007 as a quasi-natural experiment on China's transportation infrastructure quality improvement. With the initial operation of electric multiple units(EMUs) as the basis of grouping, this research examines the effect of railway speed-up on corporate total factor productivity(TFP) growth by the differencein-differences(DID) method. Overally, the results reveal positive effects both on firms' technological change and efficiency improvement, which lead to the increase of TFP. Based on subsamples divided by different regions and types of enterprises, further analysis indicates that the productivity of exporter, non-state and coastal firms has been mostly affected by the railway speed-up. These conclusions are verified by a placebo test. Besides, firms within "one-hour economic circle" have been shown more sensitive to the effect of railway speed increase.