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Digital signal acquisition system for complex nuclear reaction experiments 被引量:2
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作者 Wei-Liang Pu Yan-Lin Ye +1 位作者 Jian-Ling Lou Jia-Hao Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期124-133,共10页
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)paramet... 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. 展开更多
关键词 Digital signal acquisition system TRIGGER Programmable logic TIMESTAMP
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Logical Image Acquisition and Analysis of Android Smartphones
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作者 Nursel Yalçın Tayfun Yıldırım 《Journal of Computer and Communications》 2024年第4期139-152,共14页
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 possi... 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. 展开更多
关键词 Android Smartphone Forensics Data acquisition Data Analysis Root Privileges Digital Forensics
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Data Acquisition System for Electron Energy Loss Coincident Spectrometers 被引量:2
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作者 张弛 虞孝麒 杨涛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第6期3174-3175,共2页
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 p... 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. 展开更多
关键词 data acquisition one-dimension position-sensitive detector multiplex time- digital converter
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Performance of digital data acquisition system in gamma-ray spectroscopy 被引量:2
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作者 Di-Wen Luo Hong-Yi Wu +9 位作者 Zhi-Huan Li Chuan Xu Hui Hua Xiang-Qing Li Xiang Wang Shuang-Quan Zhang Zhi-Qiang Chen Chen-Guang Wu Yu Jin Jie Lin 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第8期12-22,共11页
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 cr... 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. 展开更多
关键词 Digital data acquisition system Gamma spectroscopy Energy resolution
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An Intermediate Frequency Acquisition Scheme for S-band Single Access Link of the Tracking and Data Relay Satellite System 被引量:1
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作者 马雨出 Gu +2 位作者 Xuemai Zhang Naitong 《High Technology Letters》 EI CAS 2001年第1期31-36,共6页
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 down... 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. 展开更多
关键词 Digital receiver Likelihood detector PN code acquisition Satellite communications
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Image Acquisition Method Based on TMS320DM642
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作者 Li Liu Yining Liu 《Journal of Computer and Communications》 2017年第5期119-124,共6页
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 spe... 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]. 展开更多
关键词 Digital Signal PROCESSOR (DSP) Image acquisition System CIS Sensor Complex PROGRAMMABLE LOGIC Device (CPLD) Work Time-Sequence PROGRAMMABLE LOGIC
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Unveiling the Pedagogical Potency of Quizlet:Enhancing Vocabulary Acquisition and Academic Performance Among Business English Major Students in China
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作者 Peng Wang 《Journal of Contemporary Educational Research》 2023年第12期157-168,共12页
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 ... 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. 展开更多
关键词 Quizlet Vocabulary acquisition Business English Academic performance Language learning China EFL Digital learning
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High-resolution data acquisition technique in broadband seismic observation systems 被引量:5
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作者 GAO Shang Hua XUE Bing +3 位作者 LI Jiang LIN Zhan CHEN Yang ZHU Xiao Yi 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第6期961-972,共12页
The dynamic range of the currently most widely used 24-bit seismic data acquisition devices is 10–20 d B lower than that of broadband seismometers, and this can affect the completeness of seismic waveform recordings ... The dynamic range of the currently most widely used 24-bit seismic data acquisition devices is 10–20 d B lower than that of broadband seismometers, and this can affect the completeness of seismic waveform recordings under certain conditions. However, this problem is not easy to solve because of the lack of analog to digital converter(ADC) chips with more than 24 bits in the market. In this paper, we propose a method in which an adder, an integrator, a digital to analog converter chip, a field-programmable gate array, and an existing low-resolution ADC chip are used to build a third-order 16-bit oversampling delta-sigma modulator. This modulator is equipped with a digital decimation filter, thus facilitating higher resolution and larger dynamic range seismic data acquisition. Experimental results show that, within the 0.1–40 Hz frequency range, the circuit board's dynamic range reaches 158.2 d B, its resolution reaches 25.99 bits, and its linearity error is below 2.5 ppm, which is better than what is achieved by the commercial 24-bit ADC chips ADS1281 and CS5371. This demonstrates that the proposed method may alleviate or even completely resolve the amplitude-limitation problem that so commonly occurs with broadband observation instruments during strong earthquakes. 展开更多
关键词 seismic data acquisition analog to digital conversion (ADC) high resolution dynamic range delta-sigma modulation
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The data acquisition algorithm designed for the SiPM-based detectors of GECAM satellite 被引量:2
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作者 Y.Q.Liu K.Gong +47 位作者 X.Q.Li X.Y.Wen Z.H.An C.Cai Z.Chang G.Chen C.Chen Y.Y.Du M.Gao R.Gao D.Y.Guo J.J.He D.J.Hou Y.G.Li C.Y.Li G.Li L.Li X.F.Li M.S.Li X.H.Liang X.J.Liu F.J.Lu H.Lu B.Meng W.X.Peng F.Shi X.L.Sun H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.L.Xiong Y.B.Xu Y.P.Xu S.Yang J.W.Yang Q.B.Yi Fan Zhang D.L.Zhang S.N.Zhang C.Y.Zhang C.M.Zhang Fei Zhang X.Y.Zhao Y.Zhao X.Zhou 《Radiation Detection Technology and Methods》 CSCD 2022年第1期70-77,共8页
Background The Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor(GECAM)consists of 2 microsatellites,each of which contains 25 GRD(LaBr3)detectors and 8 CPD(plastic scintillator)detectors.Meth... Background The Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor(GECAM)consists of 2 microsatellites,each of which contains 25 GRD(LaBr3)detectors and 8 CPD(plastic scintillator)detectors.Method silicon photomultiplier(SiPM)array is used to read each detector.The output signal of these detectors with SiPM array is very special and challenging to readout.In this study,a novel data acquisition(DAQ)algorithm for these detectors is designed and implemented,and the content of the output event packet is defined.Result and Conclusion The performances,including the event acquisition efficiency of this DAQ algorithm,are extensively verified through experimental tests.From the on-ground and in-flight tests,this algorithm has excellent performance despite the very limited resources and short development time of GECAM mission. 展开更多
关键词 Silicon photomultiplier Digital waveform processing Data acquisition
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An introduction and review on innovative silicon implementations of implantable/scalp EEG chips for data acquisition, seizure/behavior detection, and brain stimulation 被引量:1
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作者 Weiwei Shi Jinyong Zhang +2 位作者 Zhiguo Zhang Lizhi Hu Yongqian Su 《Brain Science Advances》 2020年第3期242-254,共13页
Technological advances in the semiconductor industry and the increasing demand and development of wearable medical systems have enabled the development of dedicated chips for complex electroencephalogram(EEG)signal pr... Technological advances in the semiconductor industry and the increasing demand and development of wearable medical systems have enabled the development of dedicated chips for complex electroencephalogram(EEG)signal processing with smart functions and artificial intelligence-based detections/classifications.Around 10 million transistors are integrated into a 1 mm2 silicon wafer surface in the dedicated chip,making wearable EEG systems a powerful dedicated processor instead of a wireless raw data transceiver.The reduction of amplifiers and analog-digital converters on the silicon surface makes it possible to place the analog front-end circuits within a tiny packaged chip;therefore,enabling high-count EEG acquisition channels.This article introduces and reviews the state-of-the-art dedicated chip designs for EEG processing,particularly for wearable systems.Furthermore,the analog circuits and digital platforms are included,and the technical details of circuit topology and logic architecture are presented in detail. 展开更多
关键词 biomedical chip wearable EEG system digital system chip energy-efficient circuit EEG signal acquisition
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Design and implementation of high-speed real-time data acquisition system based on FPGA 被引量:12
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作者 WANG Xu-ying LU Ying-hua ZHANG Li-kun 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2006年第4期61-66,共6页
The electromagnetic radiation will result in informa- tion leakage being recovered when computers work. This article presents a high-speed real-time data acquisition system based on peripheral component interconnect ... The electromagnetic radiation will result in informa- tion leakage being recovered when computers work. This article presents a high-speed real-time data acquisition system based on peripheral component interconnect (PCI) bus and field programmable gate array (FPGA) for sampling electromagnetic radiation caused by video signal. The hardware design and controlling flow of each module are introduced in detail. The sampling rate can reach 64 Msps and system transfers speed can be up to 128 Mb/s by using time interleaving, which increases the overall sampling speed of a system by operating two data converters in parallel. 展开更多
关键词 high-speed data acquisition FPGA PCI bus very-high-speed integrated circuit Hardware description language (VHDL) analog-to-digital converter (ADC)
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Distributed Sensor Logging: As Easy as a Mesh of Yoyos
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作者 Corey Wallis Alison Hutton +2 位作者 Steve Brown Romana Challans Paul Gardner-Stephen 《International Journal of Communications, Network and System Sciences》 2013年第6期309-315,共7页
The Mass Gathering Data Acquisition and Analysis (MaGDAA) project involved the development of hardware and software solutions to facilitate the rapid and effective collection of autonomous and survey based data during... The Mass Gathering Data Acquisition and Analysis (MaGDAA) project involved the development of hardware and software solutions to facilitate the rapid and effective collection of autonomous and survey based data during mass gathering events. The aim of the project was the development and trial of a purpose-built Open Hardware based environment monitoring sensor prototypes using IOIO (pronounced “yoyo”) boards. Data from these sensors, and other devices, was collected using Open Source software running on Android powered mobile phones, tablets and other open hardware based platforms. Data was shared using a Wi-Fi mesh network based on an Open Source project called The Serval Project. Additional data in the form of survey based questionnaires were collected using ODK Collect, one of the applications in the Open Data Kit suite. The MaGDAA project demonstrated that it is possible for researchers (through the use of Open Source software and Open Hardware) to own, visualise, and share data without the difficulties of setting up and maintaining servers. MaGDAA proved to be an effective infrastructure independent sensor logging network that enables a broad range of data collection (demographic, predispositions, motivations, psychosocial and environmental influencers and modifiers of audience behaviour, cultural value) in the field of mass gathering research. 展开更多
关键词 Sensor logging OPEN SOURCE Software OPEN SOURCE Hardware Automated Data acquisition SURVEYING
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Mechanical movement data acquisition method based on the multilayer neural networks and machine vision in a digital twin environment[version 1;peer review:2 approved]
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作者 Hao Li Gen Liu +5 位作者 Haoqi Wang Xiaoyu Wen Guizhong Xie Guofu Luo Shuai Zhang Miying Yang 《Digital Twin》 2021年第1期105-121,共17页
Background:Digital twin requires virtual reality mapping and optimization iteration between physical devices and virtual models.The mechanical movement data collection of physical equipment is essential for the implem... Background:Digital twin requires virtual reality mapping and optimization iteration between physical devices and virtual models.The mechanical movement data collection of physical equipment is essential for the implementation of accurate virtual and physical synchronization in a digital twin environment.However,the traditional approach relying on PLC(programmable logic control)fails to collect various mechanical motion state data.Additionally,few investigations have used machine visions for the virtual and physical synchronization of equipment.Thus,this paper presents a mechanical movement data acquisition method based on multilayer neural networks and machine vision.Methods:Firstly,various visual marks with different colors and shapes are designed for marking physical devices.Secondly,a recognition method based on the Hough transform and histogram feature is proposed to realize the recognition of shape and color features respectively.Then,the multilayer neural network model is introduced in the visual mark location.The neural network is trained by the dropout algorithm to realize the tracking and location of the visual mark.To test the proposed method,1000 samples were selected.Results:The experiment results shows that when the size of the visual mark is larger than 6mm,the recognition success rate of the recognition algorithm can reach more than 95%.In the actual operation environment with multiple cameras,the identification points can be located more accurately.Moreover,the camera calibration process of binocular and multi-eye vision can be simplified by the multilayer neural networks.Conclusions:This study proposes an effective method in the collection of mechanical motion data of physical equipment in a digital twin environment. Further studies are needed to perceive posture and shape data of physical entities under the multi-camera redundant shooting. 展开更多
关键词 digital twin mechanical movement data multilayer neural network machine vision data acquisition
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Photo geologic logging methods 被引量:1
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作者 ZHANG You-jing, LI Hao, GAO Yun-xiao (Department of Surveying and Mapping, Hohai University, Nanjing 210098, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期250-253,共4页
Aiming at the shortage of hydroelectric engineering geological logging methods on high side slope and big gallery, the photographic methods based on digital camera were studied. By integrating the application of techn... Aiming at the shortage of hydroelectric engineering geological logging methods on high side slope and big gallery, the photographic methods based on digital camera were studied. By integrating the application of technology of close range photogrammetry, digital image processing and GIS, the photographic geological logging information system was developed. The system has the functions of digital photography, orthophotoquad making, image mosaicking, logging factors extracting and measuring, CAD mapping, etc. The methods achieve more efficient and higher precision than the regular, and it provides a new way for the hydroelectric engineering geologic logging. 展开更多
关键词 PHOTO GEOLOGIC logging DIGITAL CAMERA close-range PHOTOGRAMMETRY GIS
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Application Analysis of Digital Signal Processor DSP in Logging Instrument
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作者 Jie Lian 《Journal of Electronic Research and Application》 2019年第2期7-10,共4页
In today’s world, the development ofeconomy has led to the continuous developmentand evolution of science and technology. Computertechnology and large-scale integration technologyhave been well developed and applied,... In today’s world, the development ofeconomy has led to the continuous developmentand evolution of science and technology. Computertechnology and large-scale integration technologyhave been well developed and applied, followed by thetechnology of digital signal processing DSP productionand application. In the field of logging, the applicationfunction of this technology plays a key role. It not onlyallows the imaging logging technology to be furtherdeveloped, but also enables fast and accurate processingof downhole signals. Therefore, among many loggingtools today, digital signal processing DSPs have beenwidely used, and their functions have been fullyutilized. This paper analyzes the application of signalprocessor DSP in logging instruments. It is hoped thatit can play a reference role in the good application anddevelopment of logging instruments. 展开更多
关键词 DIGITAL SIGNAL PROCESSOR DSP TECHNOLOGY logging instrument application
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大庆油田CIFLog测井数智云平台建设应用实践 被引量:1
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作者 李宁 刘英明 +2 位作者 王才志 原野 夏守姬 《大庆石油地质与开发》 CAS 北大核心 2024年第3期17-25,共9页
针对大庆油田生产中测井数据量大、类型多和数据来源复杂等问题,以中国石油天然气集团有限公司大型测井处理解释软件CIFLog为基础,以业务需求为主导,采用微服务架构和测井分布式云计算技术体系,研发测井大数据存储管理、中间服务层和云... 针对大庆油田生产中测井数据量大、类型多和数据来源复杂等问题,以中国石油天然气集团有限公司大型测井处理解释软件CIFLog为基础,以业务需求为主导,采用微服务架构和测井分布式云计算技术体系,研发测井大数据存储管理、中间服务层和云端测井处理解释应用等新功能,形成了大庆油田测井数智云应用平台。目前,平台已全面安装部署到大庆油田相关单位,应用效果显著。特别在大庆油田智能决策中心,平台直接用于重点水平井随钻地质导向的现场决策,大幅提升了Ⅰ类储层的钻遇率。未来平台将重点围绕新功能研发、油田数智化应用场景建设和标准化技术体系构建等开展工作,并将取得的成果及时推广复制到西南油田、塔里木油田等油气田。CIFLog云平台作为中国油气工业软件数智化建设应用的先行典范,必将发挥越来越重要的示范引领作用。 展开更多
关键词 大庆油田 CIFLog测井数智云平台 大数据 人工智能 微服务架构 分布式云计算
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大型数字平台扼杀式并购的反垄断治理路径 被引量:1
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作者 李胜利 汪靓 《科技创业月刊》 2024年第2期74-78,共5页
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。... 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。 展开更多
关键词 数字平台 初创企业 扼杀式并购 经营者集中
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数字技术并购对企业创新的影响研究
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作者 宋华盛 薛浠榕 +1 位作者 黄洁 陈菁菁 《华东经济管理》 CSSCI 北大核心 2024年第10期59-71,共13页
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... 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。 展开更多
关键词 数字化转型 技术并购 企业创新 数字创新 数字企业
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“多言少行”的数字化转型会影响公司碳排放吗? 被引量:1
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作者 孔莉 刘同州 彭宇亭 《南京审计大学学报》 CSSCI 北大核心 2024年第1期32-43,共12页
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... 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。 展开更多
关键词 多言少行 数字化转型 碳排放 环境规制 政府补助 管理层短视 融资获取
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基于LabVIEW的光纤激光器稳频系统设计
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作者 刘帆 郭文阁 +3 位作者 刘丹丹 阮军 高玉平 张首刚 《激光与红外》 CAS CSCD 北大核心 2024年第11期1681-1687,共7页
本文利用工控机、NI数据采集卡、外围光路搭建激光稳频硬件系统,以调制转移光谱技术为基础,使用LabVIEW FPGA开发了一套单频光纤激光器数字稳频控制软件。基于调制转移光谱产生的伺服控制信号,通过采集误差信号,经PI处理后控制压电陶瓷... 本文利用工控机、NI数据采集卡、外围光路搭建激光稳频硬件系统,以调制转移光谱技术为基础,使用LabVIEW FPGA开发了一套单频光纤激光器数字稳频控制软件。基于调制转移光谱产生的伺服控制信号,通过采集误差信号,经PI处理后控制压电陶瓷伸缩,将780nm的激光频率锁定在铷原子的超精细跃迁谱线上。Allan方差结果显示,短期稳定度为1.52×10^(-11)@10s;长期稳定度优于1.56×10^(-11)@100000s,可连续运行20天以上。该数字稳频软件利用图形化编程语言,大大节约开发周期,操作界面直观简洁,方便用户分析处理。已成功应用于铷87喷泉钟系统中,且该稳频系统具有通用性,可应用于原子干涉仪、激光陀螺仪等精密测量领域。 展开更多
关键词 单频光纤激光器 调制转移光谱 LabVIEW FPGA 数据采集卡 数字稳频
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