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
A control and data acquisition system was implemented for the recently developed collinear laser spectroscopy setup.This system is dedicated to data recording,storage,processing,monitoring of the beam intensity and en...A control and data acquisition system was implemented for the recently developed collinear laser spectroscopy setup.This system is dedicated to data recording,storage,processing,monitoring of the beam intensity and energy,and visualization of various spectra.In comparison to the conventional resonance nuclear reaction system,the key technique is the precise synchronization of the detected counts with the actual scanning voltage(or probing laser frequency).The functions of the system were tested by measuring the hyperfine structure spectra of stable calcium(e.g.,^(40)Ca^(+))and radioactive potassium(e.g.,^(38)K)in the bunched and continuous modes,respectively.This system will be routinely applied and further improved in subsequent laser spectroscopy experiments on unstable isotopes at the Beijing Radioactive Ion-beam Facility(BRIF).展开更多
The embedded data acquistition technology in vehicle electronic system was discussed. This technology adopts the parallel working mode, gets vehicle electronic system data by communication. This technology can provide...The embedded data acquistition technology in vehicle electronic system was discussed. This technology adopts the parallel working mode, gets vehicle electronic system data by communication. This technology can provide us a lot of information on the electronic control unit, is very useful for the development of the vehicle electronic system, and can be used in diagnosis. The key points to this technology are the timer interrupt, A/D interrupt, communication interrupt and real time operation. This technology has been validated by the application in the electronic control mechanism transmission shifting system of the tank.展开更多
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 an...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.展开更多
The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improv...The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improved the system conversion rata to 200?MHz and reduced the speed of data transporting and storing to 50?MHz. The high speed HDPLD and ECL logic parts were used to control system timing and the memory address. The multi layer print board and the shield were used to decrease interference produced by the high speed circuit. The system timing was designed carefully. The interleaving/multiplexing technique could improve the system conversion rata greatly while reducing the speed of external digital interfaces greatly. The design resolved the difficulties in high speed system effectively. The experiment proved the data acquisition system is stable and accurate.展开更多
Data acquisition, analysis and calibrating system affiliated with the vehicle is developed for the research on the automatic shift system (ASS). Considering the vehicle’s hard environment such as vibration, high and ...Data acquisition, analysis and calibrating system affiliated with the vehicle is developed for the research on the automatic shift system (ASS). Considering the vehicle’s hard environment such as vibration, high and low temperature, electromagnetic disturbance and so on, the most suitable project is selected. PC104 transfers data with ECU by serial communication and a solid state disk is used as a FLASH ROM. Some techniques including frequency division of data is adopted in the software design in order to ensure the sampling frequency. The analysis and debug software is also contrived according to the characteristic of the ASS. The system plays an important role in the development of the ASS because of the good reliability and practicability in the application.展开更多
As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency (RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and...As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency (RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and high reliability. In addition, it easily achieves long-pulse steady-state operation. During the process of the development and testing of the RF ion source, a lot of original experimental data will be generated. Therefore, it is necessary to develop a stable and reliable computer data acquisition and processing application system for realizing the functions of data acquisition, storage, access, and real-time monitoring. In this paper, the development of a data acquisition and processing application system for the RF ion source is presented. The hardware platform is based on the PXI system and the software is programmed on the LabVIEW development environment. The key technologies that are used for the implementation of this software programming mainly include the long-pulse data acquisition technology, multi- threading processing technology, transmission control communication protocol, and the Lempel-Ziv-Oberhumer data compression algorithm. Now, this design has been tested and applied on the RF ion source. The test results show that it can work reliably and steadily. With the help of this design, the stable plasma discharge data of the RF ion source are collected, stored, accessed, and monitored in real-time. It is shown that it has a very practical application significance for the RF experiments.展开更多
Neutral beam injection (NBI) heating is one of the most efficient auxiliary plasma heating methods for fusion devices. The data acquisition control system (DACS) with PXI (pe- ripheral component interconnect exte...Neutral beam injection (NBI) heating is one of the most efficient auxiliary plasma heating methods for fusion devices. The data acquisition control system (DACS) with PXI (pe- ripheral component interconnect extensions for instrumentation) data acquisition card for the first NBI system in the experimental advanced superconducting tokamak (EAST) is presented in this paper. As an important sub-system, DACS is designed to obtain physical measurement signals in the EAST NBI system and to deal and store these data with the Lempel-Ziv-Oberhumer (LZO) lossless data compression algorithm, as well as offer convenient data call-back and access inter- faces to the user for examining and analyzing the data. Experimental results show that accurate data will ensure that researchers correctly analyze it and then properly adjust the experimental parameters or operation, so DACS should take a large step in improving experimental efficiency. Tile hardware and software sections are briefly presented in this paper, and now this system has been tested to be able to work reliably and steadily.展开更多
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 o...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.展开更多
A data acquisition system for testing gas sensor array response to multi-gas is presented.The testing system is based on the character of the gas response of metal oxide semiconductor gas sensor array.The data acquisi...A data acquisition system for testing gas sensor array response to multi-gas is presented.The testing system is based on the character of the gas response of metal oxide semiconductor gas sensor array.The data acquisition is realized automatically through the real time controlling of the data acquisition card PCI1711.This system is highly attractive for electronic nose,which is a powerful tool for the discrimination of gases.展开更多
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
In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances i...In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances in terms of data channel coding which might result in a signal structure where the symbol duration is shorter than the pseudo code period. This can generate some difficulties in the DSSS signal acquisition due to the polarity inversion caused by the data modulation. To eliminate the influence due to polarity inversion, this paper proposes a novel acquisition algorithm based on the simultaneous search of the code phase, data phase and Doppler frequency. In the proposed algorithm the data phase is predicted and the correlation period for the coherent integration can be set equal to the symbol duration. Then non-coherent accumulation over different symbol is implemented in order to enhance the acquisition algorithm sensitivity; the interval of non-coherent accumulation is the least common multiple between the symbol duration and the pseudo code period. The algorithm proposed can largely minimize the SNR loss caused by data polarity inversion and enhance acquisition performance without a noticeable increase in hardware complexity. Theoretical analysis, simulation and measured results verify the validity of the algorithm.展开更多
Long pulse (of the order of 1000 s or more) SST-1 tokamak experiments demand a data acquisition system that is capable of acquiring data from various diagnostics channels without losing useful data (and hence physi...Long pulse (of the order of 1000 s or more) SST-1 tokamak experiments demand a data acquisition system that is capable of acquiring data from various diagnostics channels without losing useful data (and hence physics information) while avoiding unnecessary generation of a large volume data. SST-1 Phase-1 tokamak operation has been envisaged with data acquisition of several essential diagnostics channels. These channels demand data acquisition at a sampling rate ranging from 1 kilo samples per second (KSPS) to 1 mega samples per second (MSPS). Considering the technical characteristics and requirements of the diagnostics, a data acquisition system based on PXI and CAMAC has been developed for SST-1 plasma diagnostics. Both these data acquisition systems are scalable. Present data acquisition needs involving slow plasma diagnostics are catered by the PXI based data acquisition system. On the other hand, CAMAC data acquisition hardware meets all requirements of the SST-1 Phase-1 fast plasma diagnostics channels. A graphical user interface for both data acquisition systems (PXI and CAMAC) has been developed using LabVIEW application development software. The collected data on the local hard disk are directly streaming to the central server through a dedicated network for post-shot data analysis. This paper describes the development and integration of the data acquisition system for SST-1 Phase-1 plasma diagnostics. The integrated testing of the developed data acquisition system has been performed using SST-1 central control and diagnostics signal conditioning units. In the absence of plasma shots, the integrated testing of the data acquisition system for the initial diagnostics of SST-1 Phase-1 operation has been performed with simulated physical signals. The primary engineering objective of this integrated testing is to validate the performance of the developed data acquisition system under simulated conditions close to that of actual tokamak operation. The data acquisition is synchronized with a clock and trigger provided by the central timing system.展开更多
Research for detecting or obtaining radionuclide by gamma energy spectrum data acquisition and process system is one of the key issues about intelligent measurement of gamma-ray spectrum. For this reason, a software a...Research for detecting or obtaining radionuclide by gamma energy spectrum data acquisition and process system is one of the key issues about intelligent measurement of gamma-ray spectrum. For this reason, a software and hardware implementation schematic design based on ARM ( Advanced RISC Machines) + DSP ( Digital Signal Processor) architecture for gamma energy spectrum data acquisition and processing system is proposed. The paper discusses in detail some key technologies such as communication interface design between microcontroller ARM and digital signal processor DSP,distribution scheduling under multi-task in the ARM-Linux,DSP handling procedures for multi-channel A / D high-speed sample. At the same time,because the traditional Gaussian fitting to determine the boundary of peak is not ideal,it puts forward a weighting factor of Gaussian function least squares fitting realize boundary determined. Finally gamma-spectrum data from sodium iodide NaI( TI) scintillation detector is tested and processed in the new system. The results show that gamma energy spectrum data acquisition and process system is perfect functionality, stable and convergence in unimodal. Compared with data from conventional energy spectrometers,the system can keep better energy resolution in a wide range of pulse pass rate.展开更多
The increasing network throughput challenges the current network traffic monitor systems to have compatible high-performance data processing.The design of packet processing systems is guided by the requirements of hig...The increasing network throughput challenges the current network traffic monitor systems to have compatible high-performance data processing.The design of packet processing systems is guided by the requirements of high packet processing throughput.In this paper,we depict an in-depth research on the related techniques and an implementation of a high-performance data acquisition mechanism.Through the bottleneck analysis with the aid of queuing network model,several performance optimising methods,such as service rate increasing,queue removing and model simplification,are integrated.The experiment results indicate that this approach is capable of reducing the CPU utilization ratio while improving the efficiency of data acquisition in high-speed networks.展开更多
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
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 ...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.展开更多
A 16 kV/20 A power supply was developed for the extraction grid of prototype radio frequency(RF) ion source of neutral beam injector. To acquire the state signals of extraction grid power supply(EGPS) and control ...A 16 kV/20 A power supply was developed for the extraction grid of prototype radio frequency(RF) ion source of neutral beam injector. To acquire the state signals of extraction grid power supply(EGPS) and control the operation of the EGPS, a data acquisition and control system has been developed. This system mainly consists of interlock protection circuit board, photoelectric conversion circuit, optical fibers, industrial compact peripheral component interconnect(CPCI) computer and host computer. The human machine interface of host computer delivers commands and data to program of the CPCI computer, as well as offers a convenient client for setting parameters and displaying EGPS status. The CPCI computer acquires the status of the power supply. The system can turn-off the EGPS quickly when the faults of EGPS occur. The system has been applied to the EGPS of prototype RF ion source. Test results show that the data acquisition and control system for the EGPS can meet the requirements of the operation of prototype RF ion source.展开更多
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 ...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.展开更多
To satisfy high-precision,widc-rangc,and real-time neutron flux measurement requirements by the International Thermonuclear Experimental Reactor(ITF.R),a data acquisition and control system based on fission chamber de...To satisfy high-precision,widc-rangc,and real-time neutron flux measurement requirements by the International Thermonuclear Experimental Reactor(ITF.R),a data acquisition and control system based on fission chamber detectors and fast controller technology,has been developed for neutron flux monitor in ITER Equatorial Port#7.The signal processing units which arc based on a field programmable gate array and the PXI Express platform arc designed to realize the neutron flux measurement with I ms time resolution and a fast response less than 0.2 ms,together with real-time timestamps provided by a timing hoard.The application of the wide-range algorithm allows the system to measure up to 10^10cps with a relative error of less than 5%.Furthermore,the system is managed and controlled by a software based on the Experimental Physics and Industrial Control System,compliant with COntrol.Data Access and Communication architecture.展开更多
文摘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.
基金supported by the National Natural Science Foundation of China (Nos.12027809,U1967201,11875073,11875074 and 11961141003)National Key R&D Program of China (No.2018YFA0404403)the State Key Laboratory of Nuclear Physics and Technology,Peking University (Nos.NPT2019ZZ02,NPT2020KFY17).
文摘A control and data acquisition system was implemented for the recently developed collinear laser spectroscopy setup.This system is dedicated to data recording,storage,processing,monitoring of the beam intensity and energy,and visualization of various spectra.In comparison to the conventional resonance nuclear reaction system,the key technique is the precise synchronization of the detected counts with the actual scanning voltage(or probing laser frequency).The functions of the system were tested by measuring the hyperfine structure spectra of stable calcium(e.g.,^(40)Ca^(+))and radioactive potassium(e.g.,^(38)K)in the bunched and continuous modes,respectively.This system will be routinely applied and further improved in subsequent laser spectroscopy experiments on unstable isotopes at the Beijing Radioactive Ion-beam Facility(BRIF).
文摘The embedded data acquistition technology in vehicle electronic system was discussed. This technology adopts the parallel working mode, gets vehicle electronic system data by communication. This technology can provide us a lot of information on the electronic control unit, is very useful for the development of the vehicle electronic system, and can be used in diagnosis. The key points to this technology are the timer interrupt, A/D interrupt, communication interrupt and real time operation. This technology has been validated by the application in the electronic control mechanism transmission shifting system of the tank.
文摘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.
文摘The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improved the system conversion rata to 200?MHz and reduced the speed of data transporting and storing to 50?MHz. The high speed HDPLD and ECL logic parts were used to control system timing and the memory address. The multi layer print board and the shield were used to decrease interference produced by the high speed circuit. The system timing was designed carefully. The interleaving/multiplexing technique could improve the system conversion rata greatly while reducing the speed of external digital interfaces greatly. The design resolved the difficulties in high speed system effectively. The experiment proved the data acquisition system is stable and accurate.
文摘Data acquisition, analysis and calibrating system affiliated with the vehicle is developed for the research on the automatic shift system (ASS). Considering the vehicle’s hard environment such as vibration, high and low temperature, electromagnetic disturbance and so on, the most suitable project is selected. PC104 transfers data with ECU by serial communication and a solid state disk is used as a FLASH ROM. Some techniques including frequency division of data is adopted in the software design in order to ensure the sampling frequency. The analysis and debug software is also contrived according to the characteristic of the ASS. The system plays an important role in the development of the ASS because of the good reliability and practicability in the application.
基金the NBI team and the partial support of National Natural Science Foundation of China (No. 61363019)National Natural Science Foundation of Qinghai Province (No. 2014-ZJ-718)
文摘As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency (RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and high reliability. In addition, it easily achieves long-pulse steady-state operation. During the process of the development and testing of the RF ion source, a lot of original experimental data will be generated. Therefore, it is necessary to develop a stable and reliable computer data acquisition and processing application system for realizing the functions of data acquisition, storage, access, and real-time monitoring. In this paper, the development of a data acquisition and processing application system for the RF ion source is presented. The hardware platform is based on the PXI system and the software is programmed on the LabVIEW development environment. The key technologies that are used for the implementation of this software programming mainly include the long-pulse data acquisition technology, multi- threading processing technology, transmission control communication protocol, and the Lempel-Ziv-Oberhumer data compression algorithm. Now, this design has been tested and applied on the RF ion source. The test results show that it can work reliably and steadily. With the help of this design, the stable plasma discharge data of the RF ion source are collected, stored, accessed, and monitored in real-time. It is shown that it has a very practical application significance for the RF experiments.
基金supported by National Natural Science Foundation of China(No.11075183)
文摘Neutral beam injection (NBI) heating is one of the most efficient auxiliary plasma heating methods for fusion devices. The data acquisition control system (DACS) with PXI (pe- ripheral component interconnect extensions for instrumentation) data acquisition card for the first NBI system in the experimental advanced superconducting tokamak (EAST) is presented in this paper. As an important sub-system, DACS is designed to obtain physical measurement signals in the EAST NBI system and to deal and store these data with the Lempel-Ziv-Oberhumer (LZO) lossless data compression algorithm, as well as offer convenient data call-back and access inter- faces to the user for examining and analyzing the data. Experimental results show that accurate data will ensure that researchers correctly analyze it and then properly adjust the experimental parameters or operation, so DACS should take a large step in improving experimental efficiency. Tile hardware and software sections are briefly presented in this paper, and now this system has been tested to be able to work reliably and steadily.
文摘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.
文摘A data acquisition system for testing gas sensor array response to multi-gas is presented.The testing system is based on the character of the gas response of metal oxide semiconductor gas sensor array.The data acquisition is realized automatically through the real time controlling of the data acquisition card PCI1711.This system is highly attractive for electronic nose,which is a powerful tool for the discrimination of gases.
基金National Natural Science Foundation of China (Nos. 10134010 and 10004010)
文摘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.
基金the support of the National High Technology Research and Development Program of China (863) (Grant No. 2012AA1406)
文摘In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances in terms of data channel coding which might result in a signal structure where the symbol duration is shorter than the pseudo code period. This can generate some difficulties in the DSSS signal acquisition due to the polarity inversion caused by the data modulation. To eliminate the influence due to polarity inversion, this paper proposes a novel acquisition algorithm based on the simultaneous search of the code phase, data phase and Doppler frequency. In the proposed algorithm the data phase is predicted and the correlation period for the coherent integration can be set equal to the symbol duration. Then non-coherent accumulation over different symbol is implemented in order to enhance the acquisition algorithm sensitivity; the interval of non-coherent accumulation is the least common multiple between the symbol duration and the pseudo code period. The algorithm proposed can largely minimize the SNR loss caused by data polarity inversion and enhance acquisition performance without a noticeable increase in hardware complexity. Theoretical analysis, simulation and measured results verify the validity of the algorithm.
文摘Long pulse (of the order of 1000 s or more) SST-1 tokamak experiments demand a data acquisition system that is capable of acquiring data from various diagnostics channels without losing useful data (and hence physics information) while avoiding unnecessary generation of a large volume data. SST-1 Phase-1 tokamak operation has been envisaged with data acquisition of several essential diagnostics channels. These channels demand data acquisition at a sampling rate ranging from 1 kilo samples per second (KSPS) to 1 mega samples per second (MSPS). Considering the technical characteristics and requirements of the diagnostics, a data acquisition system based on PXI and CAMAC has been developed for SST-1 plasma diagnostics. Both these data acquisition systems are scalable. Present data acquisition needs involving slow plasma diagnostics are catered by the PXI based data acquisition system. On the other hand, CAMAC data acquisition hardware meets all requirements of the SST-1 Phase-1 fast plasma diagnostics channels. A graphical user interface for both data acquisition systems (PXI and CAMAC) has been developed using LabVIEW application development software. The collected data on the local hard disk are directly streaming to the central server through a dedicated network for post-shot data analysis. This paper describes the development and integration of the data acquisition system for SST-1 Phase-1 plasma diagnostics. The integrated testing of the developed data acquisition system has been performed using SST-1 central control and diagnostics signal conditioning units. In the absence of plasma shots, the integrated testing of the data acquisition system for the initial diagnostics of SST-1 Phase-1 operation has been performed with simulated physical signals. The primary engineering objective of this integrated testing is to validate the performance of the developed data acquisition system under simulated conditions close to that of actual tokamak operation. The data acquisition is synchronized with a clock and trigger provided by the central timing system.
基金Sponsored by the Natural Science Fundation of Jiangxi Province(Grant No.20114BAB211026 and No.20122BA-B201028)Open Science Fund from Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense,East China Institute of Technology(Grant No.2010RGET11)
文摘Research for detecting or obtaining radionuclide by gamma energy spectrum data acquisition and process system is one of the key issues about intelligent measurement of gamma-ray spectrum. For this reason, a software and hardware implementation schematic design based on ARM ( Advanced RISC Machines) + DSP ( Digital Signal Processor) architecture for gamma energy spectrum data acquisition and processing system is proposed. The paper discusses in detail some key technologies such as communication interface design between microcontroller ARM and digital signal processor DSP,distribution scheduling under multi-task in the ARM-Linux,DSP handling procedures for multi-channel A / D high-speed sample. At the same time,because the traditional Gaussian fitting to determine the boundary of peak is not ideal,it puts forward a weighting factor of Gaussian function least squares fitting realize boundary determined. Finally gamma-spectrum data from sodium iodide NaI( TI) scintillation detector is tested and processed in the new system. The results show that gamma energy spectrum data acquisition and process system is perfect functionality, stable and convergence in unimodal. Compared with data from conventional energy spectrometers,the system can keep better energy resolution in a wide range of pulse pass rate.
基金ACKNOWLEDGEMENT This project was supported by the National Natural Science Foundation of China under Grant No. 61170262 the National High Tech- nology Research and Development Program of China (863 Program) under Grants No. 2012AA012506, No. 2012AA012901, No. 2012- AA012903+5 种基金 the Specialised Research Fund for the Doctoral Program of Higher Education of China under Grant No. 20121103120032 the Humanity and Social Science Youth Founda- tion of Ministry of Education of China under Grant No. 13YJCZH065 the Opening Project of Key Lab of Information Network Security of Ministry of Public Security (The Third Re- search Institute of Ministry of Public Security) under Grant No. C13613 the China Postdoc- toral Science Foundation, General Program of Science and Technology Development Project of Beijing Municipal Education Commission of China under Grant No. km201410005012 the Research on Education and Teaching of Beijing University of Technology under Grant No. ER2013C24 the Beijing Municipal Natu- ral Science Foundation, Sponsored by Hunan Postdoctoral Scientific Program, Open Re- search Fund of Beijing Key Laboratory of Trusted Computing.
文摘The increasing network throughput challenges the current network traffic monitor systems to have compatible high-performance data processing.The design of packet processing systems is guided by the requirements of high packet processing throughput.In this paper,we depict an in-depth research on the related techniques and an implementation of a high-performance data acquisition mechanism.Through the bottleneck analysis with the aid of queuing network model,several performance optimising methods,such as service rate increasing,queue removing and model simplification,are integrated.The experiment results indicate that this approach is capable of reducing the CPU utilization ratio while improving the efficiency of data acquisition in high-speed networks.
基金supported by the National Key R&D Program of China(No.2018YFA0404403)the National Natural Science Foundation of China(Nos.12035001,12075006,11675003)the State Key Laboratory of Nuclear Physics and Technology,PKU(No.NPT2020KFY18)。
文摘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.
文摘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.
基金supported by National Natural Science Foundation of China(Contract Nos.11505225&11675216)Foundation of ASIPP(Contract No.DSJJ-15-GC03)the Key Program of Research and Development of Hefei Science Center,CAS(2016HSC-KPRD002)
文摘A 16 kV/20 A power supply was developed for the extraction grid of prototype radio frequency(RF) ion source of neutral beam injector. To acquire the state signals of extraction grid power supply(EGPS) and control the operation of the EGPS, a data acquisition and control system has been developed. This system mainly consists of interlock protection circuit board, photoelectric conversion circuit, optical fibers, industrial compact peripheral component interconnect(CPCI) computer and host computer. The human machine interface of host computer delivers commands and data to program of the CPCI computer, as well as offers a convenient client for setting parameters and displaying EGPS status. The CPCI computer acquires the status of the power supply. The system can turn-off the EGPS quickly when the faults of EGPS occur. The system has been applied to the EGPS of prototype RF ion source. Test results show that the data acquisition and control system for the EGPS can meet the requirements of the operation of prototype RF ion source.
文摘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.
文摘To satisfy high-precision,widc-rangc,and real-time neutron flux measurement requirements by the International Thermonuclear Experimental Reactor(ITF.R),a data acquisition and control system based on fission chamber detectors and fast controller technology,has been developed for neutron flux monitor in ITER Equatorial Port#7.The signal processing units which arc based on a field programmable gate array and the PXI Express platform arc designed to realize the neutron flux measurement with I ms time resolution and a fast response less than 0.2 ms,together with real-time timestamps provided by a timing hoard.The application of the wide-range algorithm allows the system to measure up to 10^10cps with a relative error of less than 5%.Furthermore,the system is managed and controlled by a software based on the Experimental Physics and Industrial Control System,compliant with COntrol.Data Access and Communication architecture.