Digital signal acquisition system for complex nuclear reaction experiments

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control parameters.The proposed digital system can be combined with a conventional analog data acquisition system to provide more flexibility.The performance of the combined system was veri-fied using experimental data.

Logical Image Acquisition and Analysis of Android Smartphones

Android smartphones largely dominate the smartphone market. For this reason, it is very important to examine these smartphones in terms of digital forensics since they are often used as evidence in trials. It is possible to acquire a physical or logical image of these devices. Acquiring physical and logical images has advantages and disadvantages compared to each other. Creating the logical image is done at the file system level. Analysis can be made on this logical image. Both logical image acquisition and analysis of the image can be done by software tools. In this study, the differences between logical image and physical image acquisition in Android smartphones, their advantages and disadvantages compared to each other, the difficulties that may be encountered in obtaining physical images, which type of image contributes to obtaining more useful and effective data, which one should be preferred for different conditions, and the benefits of having root authority are discussed. The practice of getting the logical image of the Android smartphones and making an analysis on the image is also included. Although root privileges are not required for logical image acquisition, it has been observed that very limited data will be obtained with the logical image created without root privileges. Nevertheless, logical image acquisition has advantages too against physical image acquisition.

Performance of digital data acquisition system in gamma-ray spectroscopy

A newly developed digital data acquisition system,which is based on the digital pulse processor Pixie-16 modules by XIA LLC,was tested with the c-ray detector array of the China Institute of Atomic Energy using the cray source and in-beam c-rays.A comparison between this digital data acquisition system and the conventional analog data acquisition system was made.At a low count rate,both systems exhibit good and comparable energy resolutions.At a high count rate above 8.8 k/s,while the energy resolution obtained by the analog system deteriorates significantly,the energy resolution obtained by the digital system is nearly unchanged.Meanwhile,experimental data with higher statistics can be collected by the digital system.The advantage of this digital system over the conventional analog system can be ascribed to its excellent capability of handling pile-up pulses at higher count rates,and the fact that it has nearly no dead time in data transmission and conversion.

Design of multi-channel data acquisition system based on LabVIEW and NI PXI-5105

A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data analysis using LabVIEW and NI-SCOPE device driver. The advantages of the system are that the setting is convenient, the operation is easy, the interface is friendly and the functions are practical. The experiment results show that the system has good stability and high reliability and is a powerful tool for multi-channel data acquisition.

Design and Implementation of a High-Speed Multi-Channel Data Acquisition System

A data acquisition system （DAS） to implement high-speed, real-time and multi-channel data acquisition and store is presented. The control of the system is implemented by the combination of complex programable logic device （CPLD） and digital signal processing （DSP）, the bulk buffer of the system is implemented by the combination of CPLD, DSP, and synchronous dynamic random access memory （SDRAM）, and the data transfer is implemented by the combination of DSP, first in first out （FIFO）, universal serial bus （USB） and USB hub. The system could not only work independently in single-channel mode, but also implement high-speed real-time multi-channel data acquisition system （MCDAS） by the combination of multiple single-channels. The sampling rate and data storage capacity of each channel could reach up to 100 million sampiing per second and 256 MB respectively.

Multi-channel & high-precision data acquisition devi ce for aerospace

This paper describes the detailed desi gn of data acquisition device with multi-channel and high-precision for aerosp ace.Based on detailed analysis of the advantages and disadvantages of tw o common acquisition circuits,the design factors of acquisition device focus o n accuracy,sampling rate,hardware overhead and design space.The me chanical structure of the system is divided into different card layers according to different functions and the structure has the characteristics of high reliability,conveni ence to install and scalability.To ens ure reliable operation mode,the interface uses the optocoupler isolated from th e e xternal circuit.The transmission of signal is decided by the current in the cur rent loop that consists of optocouplers between acquisition device and t est bench.In multi-channel switching circuit,by establ ishing analog multiplexer model,the selection principles of circuit modes are given.

Unveiling the Pedagogical Potency of Quizlet:Enhancing Vocabulary Acquisition and Academic Performance Among Business English Major Students in China

The effectiveness of Quizlet,an online vocabulary learning tool,in enhancing vocabulary acquisition and academic performance among Business English major students in China was investigated in this study.With emphasis on the importance of vocabulary proficiency for English learners,especially those in English-related majors,this research aimed to understand the impact of Quizlet on vocabulary mastery and its connection to overall academic success.A one-academic-year longitudinal experiment was carried out involving two classes,utilizing quantitative methods for assessing vocabulary retention and academic progress.Improvement was seen in the final exam rankings and vocabulary retention rates in Quizlet-engaged classes.Hopefully,this study could provide valuable insights for educators,curriculum designers,and researchers,guiding the optimization of language acquisition strategies in the digital age.

Data Acquisition System for Electron Energy Loss Coincident Spectrometers

A Data Acquisition System （DAQ） for electron energy loss coincident spectrometers （EELCS） has been developed. The system is composed of a Multiplex Time-Digital Converter （TDC） that measures the flying time of positive and negative ions and a one-dimension positionsensitive detector that records the energy loss of scattering electrons. The experimental data are buffered in a first-in-first-out（FIFO） memory module, then transferred from the FIFO memory to PC by the USB interface. The DAQ system can record the flying time of several ions in one collision, and allows of different data collection modes. The system has been demonstrated at the Electron Energy Loss Coincident Spectrometers at the Laboratory of Atomic and Molecular Physics, USTC. A detail description of the whole system is given and experimental results shown.

Digital AGC Based on Coherent Adjustment Cycle for DSSS Receiver

In order to meet the requirements for zero value stability of direct sequence spread spectrum(DSSS) signal processing in high dynamic scenario,digital automatic gain control(AGC) is employed to regulate power.However,conventional AGC causes degradation in the synchronization performance of DSSS receiver.Based on the theoretical analysis of the influence of digital AGC on DSSS signal synchronization,this paper proposes a new AGC algorithm,which is applicable to multi-channel digital DSSS signal receiver.By making power adjustment cycle and synchronization cycle coherent with each other adaptively,the influence of digital AGC on subsequent synchronization processing has been eliminated.Theoretical analysis,simulation results and experimental data verify the validity of the proposed algorithm.By virtue of the proposed algorithm,the influence of digital AGC on DSSS signal synchronization is eliminated.This algorithm applies to an aerospace engineering project successfully.

An Intermediate Frequency Acquisition Scheme for S-band Single Access Link of the Tracking and Data Relay Satellite System

A nonzero intermediate frequency (IF) likelihood acquisition scheme designed for S-band Single Access (SSA) link of China’s Tracking and Data Relay Satellite System (CTDRSS) is introduced. The received signal is downconverted to IF, and then direct sampled in IF using a 1-bit A/D. After the digitalization, the sampled data is detected using a hybrid likelihood acquisition scheme. Using this structure, large noise figure of the analog mixer or active filters, amplitude and phase imbalance between low-frequency in-phase and quandrature-phase channel can be avoided. An easy designing algorithm of the acquisition scheme is also derived. The performance and algorithm are verified by computer simulation.

Multi-source data-based 3D digital preservation of large scale ancient chinese architecture:A case report

The 3D digitalization and documentation of ancient Chinese architecture is challenging because of architectural complexity and structural delicacy.To generate complete and detailed models of this architecture,it is better to acquire,process,and fuse multi-source data instead of single-source data.In this paper,we describe our work on 3D digital preservation of ancient Chinese architecture based on multi source data.We first briefly introduce two surveyed ancient Chinese temples,Foguang Temple and Nanchan Temple.Then,we report the data acquisition equipment we used and the multi-source data we acquired.Finally,we provide an overview of several applications we conducted based on the acquired data,including ground and aerial image fusion,image and LiDAR(light detection and ranging)data fusion,and architectural scene surface reconstruction and semantic modeling.We believe that it is necessary to involve multi-source data for the 3D digital preservation of ancient Chinese architecture,and that the work in this paper will serve as a heuristic guideline for the related research communities.

Image Acquisition Method Based on TMS320DM642

In order to achieve high-speed, real-time and accurate, an image acquisition method based on digital signal processor (DSP) TMS320DM642 is proposed for the paper currency image acquisition [1]. System will be high speed digital signal processing (DSP) technology and complex programmable logic device (CPLD) and CIS acquisition module combination, the structure of acquisition system is given and the time series analysis, during the process of collecting this kind of design has the advantages of simple implementation, high recognition rate [2].

Application of Digital Technology in Color Test of Compound Lonicera Granules

[Objectives]The research aimed to study application of digital technique in color test of Compound Lonicera Granules.[Methods]A method of color identification of Compound Lonicera Granules based on digital technology was proposed,and the"four-point collection method of color data"was summarized through experiments.[Results]The method was used to test color of 168 batches of Compound Lonicera Granules,and it was found that the method had the advantages of fast speed,high accuracy and good repeatability.[Conclusions]The method was used to test color of 168 batches of Compound Lonicera Granules,and it was found that the method had the advantages of fast speed,high accuracy and good repeatability.

大型数字平台扼杀式并购的反垄断治理路径

大型数字平台为强化市场力量、消除潜在竞争,凭借资本、技术等优势频繁进行扼杀式并购活动。“切香肠式”的扼杀式并购短期内不会引起市场结构的显著变化,但从长远来看,对数字市场公平竞争、产品创新以及消费者福利都会产生消极影响。在我国,反垄断法对扼杀式并购的防范、识别和事后监管均面临困境。有鉴于此,我国反垄断执法机构应当结合数字经济和扼杀式并购的特点,同时在秉持“包容审慎”理念之下调整监管思路,多措并举,实现对数字平台的长效监管,保障数字经济稳定健康发展。

数字技术并购对企业创新的影响研究

在数字经济蓬勃发展的趋势下,技术并购成为企业数字化转型的重要途径。文章基于2007—2021年中国A股上市公司数据,利用三重差分法探究数字技术并购对企业创新的影响。研究发现,数字技术并购能够显著促进企业创新,并且研发资源挤入效应、知识溢出效应和市场规模效应是三个重要的作用渠道。异质性分析表明,当主并企业所属行业竞争激烈、所在地区知识溢出便利,主并企业属于劳动密集型,目标企业为大型或科技型企业时,数字技术并购的创新促进作用更明显。此外,数字技术并购能够显著促进目标数字企业创新,当其规模较大、处于成长期或为科技型企业时,促进作用更明显。研究结论为企业数字化转型路径选择和数字经济政策设计实现“创新双赢”提供启示。

“多言少行”的数字化转型会影响公司碳排放吗?

以制造业和重污染上市公司2009—2020年的数据为样本,从不同角度实证研究公司“多言少行”数字化转型对碳排放的影响。研究发现:“多言少行”数字化转型会显著促进公司碳排放增加;相比于“少言少行”和“少言多行”,多“言”的数字化转型有更明显的增加作用;相比于其他过程,“多言少行”对生产过程的碳排放正向影响更为明显;环境规制显著抑制了“多言少行”对碳排放的促进作用。进一步分析发现,“多言少行”对碳排放的作用受到“言”增多和“行”减少的共同影响,提高政府补助、降低融资约束、管理层短视上升在其中起到了机制作用。研究结论有助于认识到“多言少行”数字化转型的机会主义和潜在风险,为监管部门规范数字化转型信息披露提供依据。

基于FPGA的多通道温度采编装置设计

针对飞行试验中对设备温度测量的需求,设计了一种适用于飞行测试的高精度多通道温度采编装置。设计以FPGA构建信号采集处理系统,采用AD8227和AD590来实现信号的调理和温度冷端补偿,通过标准RS422协议实现16路温度信号传输,并采取线性拟合的方式对输出进行非线性校正,提高了系统准确率和稳定性。测试结果表明,测温电路全量程内最大测量误差为±0.083%F.S.。经过测试验证,该方案传输过程无丢帧零误码,系统运行高效、可靠。

数字并购情境下目标方留任数字背景高管如何影响并购方数字创新绩效?

数字人才已经成为企业实现数字化转型和数字创新的关键资源,也是数字并购中并购方重点吸收和保留的数字资源。在数字并购情境下,以新一代信息技术企业为研究对象,基于资源基础理论,将目标方留任数字背景高管视为一种数字资源。将数字化转型划分为数字技术集成和数字技术应用两个维度,考察了目标方留任数字背景高管、并购方数字化转型和并购方数字创新绩效三者的作用机制,并以数字并购事件为研究样本,利用回归分析方法进行了实证检验。研究发现:目标方留任数字背景高管对数字创新短期绩效和长期绩效均具有正向影响;数字技术集成和数字技术应用发挥双重中介效应。在目标方留任数字背景高管与数字创新短期绩效关系中,数字技术集成发挥的中介效应大于数字技术应用;在目标方留任数字背景高管与数字创新长期绩效关系中,数字技术应用发挥的中介效应大于数字技术集成。研究有助于明晰数字并购情境下的数字创新绩效实现机制,帮助企业实现数字化转型和数字创新目标。

基于JTAG接口的多通道测试系统设计

为了实现雷达数字接收机的自动采集与分析,通过电路的JTAG接口和Quartus软件的SignalTap功能,将数字IQ数据进行采集和存储,经过嵌入式MATLAB的组合封装和LabVIEW测试算法的通用化分析,实现了多通道数字化接收机性能指标的便捷化测试,提升了系统的自动测试效率。