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Energy and angular distribution of recoil proton of fast neutron in scintillation fiber:a simulation study

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Nuclear Science and Techniques 2009年第1期20卷 42-45页

作者： ma qingli TANG Shibiao ZOU Jiwei Electronics Department Electronic Engineering Institute Hefei 230038 China Department of Modem Physics University of Science and Technology of China Hefei 230026 China Department of Scientific Research Electronic Engineering Institute Hefei 230038 China

Due to their low cost,big reaction cross-section with neutrons,flexibility,and convenience for long distance data transfer,plastic scintillation fibers(PSF)have been increasingly used as detectors or sensors for high-energy neutron *** this paper,Geant4 Monte Carlo simulation tool was used to obtain some characteristics of energy and angular distributions of recoil protons in plastic scintillation fibers irradiated by fast *** plastic fiber with BCF-20 as the core and an acrylic outer cladding was used in the *** results show that there is a big range of energy and angular distribution of recoil protons in energies varying inversely with the recoil angle.

关键词：能量分布快中子照射辐射线核技术

Some characteristics of X-ray imaging for energy region of over 100 keV using plastic scintillation fiber array

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Nuclear Science and Techniques 2007年第3期18卷 172-175页

作者： TANG Shibiao ma qingli YIN Zejie HUANG Huan Department of Modern Physics University of Science and Technology of China Hefei 230026 China Electronics Department Electronic Engineering Institute Hefei 230038 China

In this work, characteristics of using PSFs (plastic scintillation fibers) coupled with CCD (charge-coupled devices ) to build area detectors for high energy X-ray imaging are studied with a Monte Carlo simulation, which cover an energy range of a few hundred keV to about 20 MeV. It was found that the efficiency of PSF in detecting X-ray with energy above a few hundred keV is low. We can use large incident flux to increase the output signal to noise ratio (SNR). The performance can also be improved by coating PSF with X-ray absorption layers and the MTF of the system is presented. By optimizing the absorption layer thickness, the crosstalk of the area detector built with PSF decreases.

关键词：塑料发光纤维 X射线成像信噪比 SNR

Determination of spatial resolution of plastic scintillation fiber array with a simple method

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Nuclear Science and Techniques 2007年第2期18卷 111-114页

作者： TANG Shibiao ma qingli YIN Zejie HUANG Huan Department of Modern Physics University of Science and Technology of China Hefei 230027 China Electronics Department Electronic Engineering Institute Hefei 230038 China

The spatial resolution of a position sensitive gamma-ray detector configuration based on plastic scintillation fiber array was measured using a Monte Carlo simulation method. Both point spread function and modulation transfer function (MTF) were presented. The factors that influence the spatial resolution were also discussed. The results of the simulation showed that the intrinsic spatial resolution was consistent with the size of the physical pixels and a few centimeters spatial resolution could be obtained under certain circumstances.

关键词：塑料闪烁光纤阵空间分辨率测定简单方法

Two-dimensional X-ray imaging using plastic scintillating fiber array

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Nuclear Science and Techniques 2008年第1期19卷 50-52页

作者： ma qingli TANG Shibiao ZOU Jiwei XU Dongzhe Electronics Department Electronic Engineering Institute Hefei 230038 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China Department of Scientific Research Electronic Engineering Institute Hefei 230038 China Department of Modern Mechanics University of Science and Technology of China Hefei 230026 China

Due to its low cost, flexibility and convenience for long distance data transfer, plastic scintillation fiber (PSF) have been increasingly used in building detectors or sensors for detecting various radiations and imaging. In this work, the performance of using PSF coupled with charge-coupled devices (CCD) to build area detectors for 2D X-ray imaging is studied. We describe the experimental setup and show the obtained images from CCD. Modulation Transfer Function (MTF) of the PSF array is also presented and compared to earlier reports.

关键词：波导光学射线 X线成像闪烁纤维

Simulation study of BGO array for characteristic gamma rays from neutron-stimulated elements

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Nuclear Science and Techniques 2007年第6期18卷 354-357页

Characteristic gamma rays of 100 keV to about 6 MeV from different elements stimulated by neutrons have been applied to diagnosis biological *** this paper,BGO detectors are used for the spectrum simulation. Signals from a single crystal and after correction are both obtained,and the energy spectrum summing adjacent signals seems possible to achieve excellent energy resolution for such high-energy *** ideal suppositions are in- troduced and some other information,such as spatial resolution and difficult electronics,should be considered after this correction.

关键词： α射线能量光谱 BGO 中子

Energy-Efficient MTC Data Offloading in Wireless Networks Based on K-Means Grouping Technique

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Journal of Computer and Communications 2019年第2期7卷 47-61页

作者： Juma Saidi Ally Muhammad Asif qingli ma Department of Information and Communication Engineering University of Science and Technology of China<br/> Key Laboratory of Wireless-Optical Communications Chinese Academy of Sciences Hefei China

machine-type communication (MTC) devices provide a broad range of data collection especially on the massive data generated environments such as urban, industrials and event-enabled areas. In dense deployments, the data collected at the closest locations between the MTC devices are spatially correlated. In this paper, we propose a k-means grouping technique to combine all MTC devices based on spatially correlated. The MTC devices collect the data on the event-based area and then transmit to the centralized aggregator for processing and computing. With the limitation of computational resources at the centralized aggregator, some grouped MTC devices data offloaded to the nearby base station collocated with the mobile edge-computing server. As a sensing capability adopted on MTC devices, we use a power exponential function model to compute a correlation coefficient existing between the MTC devices. Based on this framework, we compare the energy consumption when all data processed locally at centralized aggregator or offloaded at mobile edge computing server with optimal solution obtained by the brute force method. Then, the simulation results revealed that the proposed k-means grouping technique reduce the energy consumption at centralized aggregator while satisfying the required completion time.

关键词： machine-Type Communication Correlation Data Offloading Grouping Technique Differential Entropy Power Exponential Function

内置频率对Duffing振子微弱二进制相移键控信号盲检测影响

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国防科技大学学报 2019年第1期41卷 80-88页

作者：吴彦华马庆力国防科技大学电子对抗学院安徽合肥230037

采用Duffing振子实现对微弱二进制相移键控(Binary Phase Shift Keying, BPSK)信号的盲检测时,Duffing系统输出的周期态和混沌态转换之间存在过渡带。针对这一问题,推导出过渡带时长和Duffing系统内置频率之间的关系表达式;指出内置频... 详细信息

采用Duffing振子实现对微弱二进制相移键控(Binary Phase Shift Keying, BPSK)信号的盲检测时,Duffing系统输出的周期态和混沌态转换之间存在过渡带。针对这一问题,推导出过渡带时长和Duffing系统内置频率之间的关系表达式;指出内置频率越高,过渡带时间越短;仿真实验给出时间频率响应曲线。内置频率的提高,会降低系统检测微弱信号的灵敏度。针对这一问题,推导出周期态下Duffing系统输出幅度作为因变量、内置频率作为自变量的表达式;仿真实验给出幅频响应曲线。针对微弱BPSK信号盲检测,建立变尺度方法和检测阵列相结合的基于S变换提取Duffing系统输出幅度包络的微弱BPSK信号盲检测模型,仿真实验验证了模型方法的有效性。

关键词： Duffing振子内置频率过渡带时长检测灵敏度 S变换

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Duffing振子微弱信号盲检测方法

系统工程与电子技术 2017年第11期39卷 2414-2421页

作者：吴彦华马庆力电子工程学院通信对抗系安徽合肥230037

针对强噪声中微弱信号的盲检测问题,研究了待检信号与Duffing系统内置信号频差和相差对系统相图的影响,指出由于频差的存在,Duffing系统相轨迹演化将进入周期性混沌状态。通过建立正相振子和反相振子检测方程以及相图分段处理,提出了Duf... 详细信息

针对强噪声中微弱信号的盲检测问题,研究了待检信号与Duffing系统内置信号频差和相差对系统相图的影响,指出由于频差的存在,Duffing系统相轨迹演化将进入周期性混沌状态。通过建立正相振子和反相振子检测方程以及相图分段处理,提出了Duffing振子微弱信号盲检测识别算法并建立了盲检测模型。仿真实验表明,在-40dB信噪比下仍然可以有效实现对微弱信号的盲检测。

关键词： Duffing振子频差周期性混沌盲检测

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自发地理信息的应用问题及应对策略

重庆大学学报（自然科学版） 2017年第9期40卷 83-88页

作者：杨清丽马超徐青 61243部队信息工程大学测绘学院

自发地理信息的迅速发展逐渐成为了地学领域的研究热点,研究分析了自发地理信息应用于地图制图更新中面临的数据质量评价、几何数据融合与属性信息匹配转换等核心问题,在此基础上提出了自发地理信息分析与融合处理的一般流程,并针对每... 详细信息

自发地理信息的迅速发展逐渐成为了地学领域的研究热点,研究分析了自发地理信息应用于地图制图更新中面临的数据质量评价、几何数据融合与属性信息匹配转换等核心问题,在此基础上提出了自发地理信息分析与融合处理的一般流程,并针对每个问题分别提出了相应的解决策略;最后,利用北京地区OSM数据,对流程和策略进行了验证。

关键词：自发地理信息数据质量评价数据融合属性匹配