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Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation

Nuclear Science and Techniques 2024年第5期35卷 99-108页

作者： You-Ming Deng Yong-Bin Leng Xing-yi Xu Jian Chen yi-mei zhou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle *** is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter ***,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this *** with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed *** basic principles of the method,simulation,and experimental comparison are also *** on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal *** results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.

关键词： Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF

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Determining beam transverse absolute position by triangulation of multi-electrode signal phase differences

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Nuclear Science and Techniques 2024年第8期35卷 38-47页

作者： Xing Yang Hong‑Shuang Wang yi‑mei zhou Yong‑Bin Leng Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China

Accurate measurement of the transverse position of a beam is crucial in particle accelerators because it plays a key role in determining the beam *** methods for beam-position measurement rely on the detection of image currents induced on electrodes or narrow-band wake field induced by a beam passing through a cavity-type ***,these methods have *** indirect measurement of multiple parameters is computationally complex,requiring external calibration to determine the system parameters in ***,the utilization of the beam signal information is ***,this study proposes a novel method for measuring the absolute electron beam transverse *** utilizing the geometric relationship between the center position of the measured electron beam and multiple detection electrodes and by analyzing the differences in the arrival times of the beam signals detected by these electrodes,the absolute transverse position of the electron beam crossing the electrode plane can be *** method features absolute position measurement,a position sensitivity coefficient independent of vacuum chamber apertures,and no requirement for a symmetrical detector electrode *** feasibility of this method is validated through numerical simulations and beam experiments.

关键词： Electron beam bunch-by bunch diagnostics Bunch position measurement Triangulation method Bunch phase Bunch-by-bunch Transverse position Pickup signal

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HOTCAP:a new software package for high-speed oscilloscopebased three-dimensional bunch charge and position measurement

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Nuclear Science and Techniques 2021年第11期32卷 163-173页

作者： Xing-yi Xu Yong-Bin Leng Bo Gao yi-mei zhou Shan-Shan Cao Jian Chen Fang-zhou Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

A software package to be used in high-speed oscilloscope-basedthree-dimensionalbunch-by-bunch charge and position measurement is *** software package takes the pick-up electrode signal waveform recorded by the high-speed oscilloscope as input,and it calculates and outputs the bunch-by-bunch charge and *** addition to enabling a three-dimensional observation of the motion of each passing bunch on all beam position monitor pick-up electrodes,it offers many additional features such as injection analysis,bunch response function reconstruction,and turn-by-turn beam *** software package has an easy-to-understand graphical user interface and convenient interactive operation,which has been verified on the Windows 10 system.

关键词： Bunch-by-bunch measurement HOTCAP software package Data analysis High-speed oscilloscope

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Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application

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Nuclear Science and Techniques 2024年第4期35卷 165-175页

作者： Hong-Shuang Wang Xing Yang Yong-Bin Leng yi-mei zhou Ji-Gang Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage *** technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous *** bunch signal is obtained using a button electrode with a bandwidth of several *** data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 GS/s,and the single-shot sampling data buffer covered thousands of *** bunch-length and synchronous phase information were extracted via offline calculations using Python *** calibration coefficient of the system was determined using a commercial streak ***,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the Shanghai Synchrotron Radiation Facility(SSRF),and longitudinal instabilities were observed during the single-bunch accumulation process at Hefei Light Source(HLS).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 *** dynamic range exceeded 10 *** technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings.

关键词： Bunch-by-bunch diagnostic Bunch-length measurement Synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability

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Touschek lifetime study based on the precise bunch-by-bunch BCM system at SSRF

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Nuclear Science and Techniques 2019年第9期30卷 126-133页

作者： Fang-zhou Chen Zhi-Chu Chen yi-mei zhou Ning Zhang Bo Gao Xing-yi Xu Yong-Bin Leng Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049 China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201200 China

Continuous tracking of bunch charges is the key to maintain stable operations in a storage ring in top-up mode. Recently, a precise bunch-by-bunch beam-current measurement (BCM) system has been developed at the Shanghai Synchrotron Radiation Facility. To avoid the influence of longitudinal oscillation on the amplitudes of the sampling points, a method called two-point equilibrium sampling is introduced. The results, obtained during routine operation time, show that the relative resolution of the measurement of the bunch charges is better than 0.02%. With this high resolution, the new BCM system is able to monitor the bunch-by-bunch beam lifetime. By using the filling pattern information, the Touschek lifetime and the vacuum lifetime can also be calculated. In this paper, the principle of the new method and the experiments is presented in detail.

关键词： Beam-current measurement Bunch-bybunch Touschek lifetime Vacuum lifetime SSRF

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Bunch-by-bunch longitudinal phase monitor at SSRF

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Nuclear Science and Techniques 2018年第8期29卷 149-154页

作者： yi-mei zhou Han-Jiao Chen Shan-Shan Cao Yong-Bin Leng Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai Synchrotron Radiation Facility Chinese Academy of Sciences

Beam signals captured from a button-type pickup contain multidimensional information including the bunch charge,transverse position,bunch length,and longitudinal phase.A bunch phase monitor,which retrieves longitudinal phase information from a pickup signal at a bunch-by-bunch rate,has been developed at the Shanghai Synchrotron Radiation *** paper introduces the basic principles,system setup,data processing method,and preliminary experimental results of this *** systematic measurement error introduced by the limited system bandwidth,bunch length,and bunch charge variation was studied using simulation *** random measurement uncertainty was evaluated using experimental beam *** experimental result shows that the longitudinal phase resolution of this system is better than 1.0 *** first application,measuring the relationship between the longitudinal phase and bunch charge to determine the energy loss factor,was implemented,and the preliminary result is also discussed.

关键词：监视器 SSRF 数据处理方法同步加速器试验性信号信息系统

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Genetic and Epigenetic Alterations of DLC-1,a Candidate Tumor Suppressor Gene,in Nasopharyngeal Carcinoma

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 349-355页

作者： Dan PENG Cai-Ping REN Hong-mei yi Liang zhou Xu-Yu YANG Hui LI Kai-Tai YAO Cancer Research Institute,Xiangya School of Medicine,Central South University,Changsha 410078,China Cancer Research Institute Xiangya School of Medicine Central South UniversityChangsha 410078 China

The DLC-1 gene,located at the human chromosome region 8p22,behaves like a tumorsuppressor gene and is frequently deleted in diverse *** deletion of 8p22 is not an uncommon eventin nasopharyngeal carcinoma(NPC),therefore we explored the expression levels of the DLC-1 gene in NPCsand NPC cell lines by reverse transcription-polymerase chain *** results showed the mRNA levelof DLC-1 was *** identify the mechanism of DLC-1 downregulation in NPC,we investigatedthe methylation status of the DLC-1 gene using methylation-specific PCR,and found that 79%(31 of 39)ofthe NPC tissues and two DLC-1 nonexpressing NPC cell lines,6-10B and 5-8F,were methylated in theDLC-1 CpG *** PCR was also carried out,and loss of heterozygosity was found at fourmicrosatellite sites(D8S552,D8S 1754,D8S 1790 and D8S549)covering the whole DLC-1 gene with ratiosof 33%(4 of 12 informative cases),18%(2 of 11),5%(1 of 18),and 25%(3 of 12),***,our results suggest that DLC-1 might be an NPC-related tumor suppressor gene affected by aberrantpromoter methylation and gene deletion.

关键词： DLC-I nasopharyngeal carcinoma hypermethylation loss of heterozygosity

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Malicious Document Detection Based on GGE Visualization

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Computers, Materials & Continua 2025年第1期82卷 1233-1254页

作者： Youhe Wang yi Sun Yujie Li Chuanqi zhou Henan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers has become particularly ***,detection methods based on document structure and behavioral features encounter challenges in feature engineering,these methods not only have limited accuracy,but also consume large resources,and usually can only detect documents in specific formats,which lacks versatility and *** address such problems,this paper proposes a novel malicious document detection method-visualizing documents as GGE images(Grayscale,Grayscale matrix,Entropy).The GGE method visualizes the original byte sequence of the malicious document as a grayscale image,the information entropy sequence of the document as an entropy image,and at the same time,the grayscale level co-occurrence matrix and the texture and spatial information stored in it are converted into grayscale matrix image,and fuses the three types of images to get the GGE color *** Convolutional Block Attention Module-EfficientNet-B0(CBAM-EfficientNet-B0)model is then used for classification,combining transfer learning and applying the pre-trained model on the ImageNet dataset to the feature extraction process of GGE *** shown in the experimental results,the GGE method has superior performance compared with other methods,which is suitable for detecting malicious documents in different formats,and achieves an accuracy of 99.44%and 97.39%on Portable Document Format(PDF)and office datasets,respectively,and consumes less time during the detection process,which can be effectively applied to the task of detecting malicious documents in real-time.

关键词： Malicious document visualization EfficientNet-B0 convolutional block attention module GGE image

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The injury progression of T lymphocytes in a mouse model with subcutaneous injection of a high dose of sulfur mustard

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Journal of Medical Colleges of PLA(China) 2014年第3期29卷 162-172页

作者： yi-zhou mei Xiao-Rui Zhang Ning Jiang Jun-Ping Cheng Feng Liu Pan Zheng Wen-Xia zhou Yong-Xiang Zhang State Key Laboratory of Toxicology and Medical Countermeasures Beijing Institute of Pharmacology and Toxicology

Background: In clinical studies, the findings on sulfur mustard(SM) toxicity for CD3+CD4+ and CD3+CD8+ T lymphocyte subsets are contradictory. In animal experiments, the effect of SM on the T cell number and proliferation is incompatible and is even the opposite of the results in human studies. In this study, we observed the dynamic changes of T lymphocytes in the first week in a high-dose SM-induced ***: Mice were exposed to SM by subcutaneous injection(20 mg/kg) and were sacrificed 4 h, 24 h, 72 h and 168 h later. Spleen T lymphocyte proliferation was evaluated by 3H-Td R. Flow cytometric analysis was used to observe the percentage of CD3+CD4+ and CD3+CD8+ T lymphocyte subsets. The IL-1e assayed using the Luminex method. DNA damage in bone marrow ceβ, IL-6, IL-10 and TNF-lls was observed with α levels in plasma werthe single cell gel electrophoresis technique(SCGE).Results: SM continuously inhibited the proliferation of lymphocytes for 7 days, and there was a significant rebound of Con A-induced T lymphocyte proliferation only at 24 h. The percentage of CD3+CD4+ and CD3+CD8+ lymphocytes was upregulated, which was accompanied by increased IL-1β and TNF-creased in the PG group at 4 h. The peak of lymphocytic apoptα and decreased IL-10. The IL-6 level was gradually deosis and DNA damage occurred at 24 h and 72 h, respectively. Conclusion: Our results show that SM significantly inhibited T lymphocyte proliferation as well as induced CD3+CD4+ and CD3+CD8+ upregulation. SM intoxication also significantly increased the levels of pro-inflammatory cytokines(IL-1β, IL-6 and TNF-α) and inhibited the level of anti-inflammatory cytokine IL-10. Our results may partly be due to the significant SM induced significant apoptosis and necrosis of lymphocytes as well as DNA damage of bone marrow cells. The results provided a favorable evaluation of SM immune toxicity in an animal model.

关键词： Sulfur Mustard T lymphocyte Apoptosis Cytokine DNA damage

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Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang zhou Chen Shen Zhenghao Wu Xingying Lan yi Xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： Condensation reactions

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