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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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作者 Hong-Shuang Wang Xing Yang +2 位作者 Yong-Bin Leng Yi-Mei Zhou Ji-Gang Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期165-175,共11页
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 rings.This technique uses the time–frequency-domain joint analysis of the bunch si... 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 rings.This 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 phase.The bunch signal is obtained using a button electrode with a bandwidth of several gigahertz.The 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 turns.The bunch-length and synchronous phase information were extracted via offline calculations using Python scripts.The calibration coefficient of the system was determined using a commercial streak camera.Moreover,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 ps.The dynamic range exceeded 10 ms.This technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings. 展开更多
关键词 Bunch-by-bunch diagnostic Bunch-length measurement Synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability
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Seismic fragility analysis of clay-pile-pier systems considering the optimization of ground motion intensity measures 被引量:1
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作者 Zhang Panpan Zhang Lei Zhang Zhen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期965-977,共13页
The performance of clay-pile-pier system under earthquake shaking was comprehensively examined via three-dimensional finite element analyses,in which the complex stress-strain relationships of a clay and piled pier sy... The performance of clay-pile-pier system under earthquake shaking was comprehensively examined via three-dimensional finite element analyses,in which the complex stress-strain relationships of a clay and piled pier system were depicted by a hyperbolic-hysteretic and an equivalent elastoplastic model,respectively.One hundred twenty ground motions with varying peak accelerations were considered,along with the variations in bridge superstructure mass and pile flexural rigidity.Comprehensive comparison studies suggested that peak pile-cap acceleration and peak pile-cap velocity are the optimal ground motion intensity measures for seismic responses of the pier and the pile,respectively.Furthermore,based on two optimal ground motion intensity measures and using curvature ductility to quantify different damage states,seismic fragility analyses were performed.The pier generally had no evident damage except when the bridge girder mass was equal to 960 t,which seemed to be comparatively insensitive to the varying pile flexural rigidity.In comparison,the pile was found to be more vulnerable to seismic damage and its failure probabilities tended to clearly reduce with the increment of pile flexural rigidity,while the influence of the bridge girder mass was relatively minor. 展开更多
关键词 clay-pile-pier system seismic fragility analysis ground motion intensity measures damage probability
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Advancing Malaria Prediction in Uganda through AI and Geospatial Analysis Models
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作者 Maria Assumpta Komugabe Richard Caballero +1 位作者 Itamar Shabtai Simon Peter Musinguzi 《Journal of Geographic Information System》 2024年第2期115-135,共21页
The resurgence of locally acquired malaria cases in the USA and the persistent global challenge of malaria transmission highlight the urgent need for research to prevent this disease. Despite significant eradication e... The resurgence of locally acquired malaria cases in the USA and the persistent global challenge of malaria transmission highlight the urgent need for research to prevent this disease. Despite significant eradication efforts, malaria remains a serious threat, particularly in regions like Africa. This study explores how integrating Gregor’s Type IV theory with Geographic Information Systems (GIS) improves our understanding of disease dynamics, especially Malaria transmission patterns in Uganda. By combining data-driven algorithms, artificial intelligence, and geospatial analysis, the research aims to determine the most reliable predictors of Malaria incident rates and assess the impact of different factors on transmission. Using diverse predictive modeling techniques including Linear Regression, K-Nearest Neighbor, Neural Network, and Random Forest, the study found that;Random Forest model outperformed the others, demonstrating superior predictive accuracy with an R<sup>2</sup> of approximately 0.88 and a Mean Squared Error (MSE) of 0.0534, Antimalarial treatment was identified as the most influential factor, with mosquito net access associated with a significant reduction in incident rates, while higher temperatures correlated with increased rates. Our study concluded that the Random Forest model was effective in predicting malaria incident rates in Uganda and highlighted the significance of climate factors and preventive measures such as mosquito nets and antimalarial drugs. We recommended that districts with malaria hotspots lacking Indoor Residual Spraying (IRS) coverage prioritize its implementation to mitigate incident rates, while those with high malaria rates in 2020 require immediate attention. By advocating for the use of appropriate predictive models, our research emphasized the importance of evidence-based decision-making in malaria control strategies, aiming to reduce transmission rates and save lives. 展开更多
关键词 MALARIA Predictive Modeling Geospatial Analysis Climate Factors Preventive Measures
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Using Fuzzy Theory in %GR&R and NDC of Measurement System Analysis
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作者 Tsu-Ming Yeh Fan-Yun Pai Chi-Wen Huang 《Engineering(科研)》 2015年第4期161-176,共16页
ISO9001:2000 and TS 16949 have become the major quality system management models in present traditional and Hi-tech industries. The Measurement System Analysis (MSA) Reference Manual, on the other hand, is one of the ... ISO9001:2000 and TS 16949 have become the major quality system management models in present traditional and Hi-tech industries. The Measurement System Analysis (MSA) Reference Manual, on the other hand, is one of the core tools in ISO/TS 16949. MSA aims to evaluate Gauge Repeatability and Reproducibility (GR&R) where the control, monitoring, and maintenance of the measurement process are required in measurement systems so that the measurement capability could be ensured under statistical control. An ideal measurement system should present the statistical characteristic of zero error on any measured product. Nevertheless, such an ideal measurement system hardly exists. Managers therefore have to adopt such measurement systems with unsatisfactory statistical characteristics. Traditional MSA indexes are constructed with definite observed values. Nevertheless, measurements with observed values are not entirely error-free. For this reason, this study proposes to research three cases in a case company and apply the integration of Fuzzy Theory and GR&R to discuss the differences in the evaluation index GR&R and the Number of Distinct Categories (NDC). Substituting fuzzy numbers for definite numbers found that the data of %GR&R were increased and NDC was decreased after fuzzification. Such results verify that the fuzzified %GR&R and NDC become stricter in the determination criterion. The research outcomes could assist the case company in improving the reference data of measurement systems and promoting the measurement quality. 展开更多
关键词 FUZZY Theory GR&R Measurement System Analysis (MSA) NUMBER of DISTINCT Categorie (NDC)
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Item-Level Analysis of the Revised Occupational Therapy Fieldwork Performance Evaluation Applied in Practice
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作者 Cynthia L. Sears Brad E. Egan +1 位作者 Patricia F. Tomsic Craig A. Velozo 《Open Journal of Therapy and Rehabilitation》 2024年第2期145-159,共15页
Competency-based assessments for healthcare professionals are critical for safe and effective client outcomes. Rehabilitation clinical skill competency assessments must be validated and revised to produce safe and ski... Competency-based assessments for healthcare professionals are critical for safe and effective client outcomes. Rehabilitation clinical skill competency assessments must be validated and revised to produce safe and skilled practitioners. The revised American Occupational Therapy Association (AOTA) Fieldwork Performance Evaluation (FWPE) instrument measures occupational therapy student performance to determine readiness for practice. The assessment includes thirty-seven competencies that address both profession specific clinical skills and general professional behavior skills. The objective of this study was to use Rasch methods to explore the use of the revised FWPE in actual fieldwork practice and to determine the instrument’s psychometric properties when separating the item components into two distinct subdomains: General Health Professions Competences and Occupational Therapy-Specific Competencies. Internal construct validity and test reliability were analyzed using data from 149 occupational therapy students after completing their initial Level II A fieldwork clinical internship. This study examined the item difficulty hierarchy, item fit, person-fit to model, person separation index, person separation reliability coefficient, strata, ceiling and floor effect, and unidimensionality of the FWPE instrument as a whole and as two separate domains. With the exception of not meeting the criteria for unidimensionality, the full FWPE instrument and the Occupational Therapy-Specific Competencies subdomain showed acceptable item-level psychometrics for reliability and precision. While the General Health Professions Competencies subdomain showed good item-level psychometrics, it was below the criterion for reliability and only separated the sample into two strata. Results support the validity, reliability, and clinical use of the revised FWPE full instrument and the Occupational Therapy-Specific Competencies subdomain to measure entry-level clinical skill competencies in practice. 展开更多
关键词 REHABILITATION Competency-Based Assessments Occupational Therapy Measurement Rasch Analysis
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Online Capacitor Voltage Transformer Measurement Error State Evaluation Method Based on In-Phase Relationship and Abnormal Point Detection
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作者 Yongqi Liu Wei Shi +2 位作者 Jiusong Hu Yantao Zhao Pang Wang 《Smart Grid and Renewable Energy》 2024年第1期34-48,共15页
The assessment of the measurement error status of online Capacitor Voltage Transformers (CVT) within the power grid is of profound significance to the equitable trade of electric energy and the secure operation of the... The assessment of the measurement error status of online Capacitor Voltage Transformers (CVT) within the power grid is of profound significance to the equitable trade of electric energy and the secure operation of the power grid. This paper advances an online CVT error state evaluation method, anchored in the in-phase relationship and outlier detection. Initially, this method leverages the in-phase relationship to obviate the influence of primary side fluctuations in the grid on assessment accuracy. Subsequently, Principal Component Analysis (PCA) is employed to meticulously disentangle the error change information inherent in the CVT from the measured values and to compute statistics that delineate the error state. Finally, the Local Outlier Factor (LOF) is deployed to discern outliers in the statistics, with thresholds serving to appraise the CVT error state. Experimental results incontrovertibly demonstrate the efficacy of this method, showcasing its prowess in effecting online tracking of CVT error changes and conducting error state assessments. The discernible enhancements in reliability, accuracy, and sensitivity are manifest, with the assessment accuracy reaching an exemplary 0.01%. 展开更多
关键词 Capacitor Voltage Transformer Measurement Error Online Monitoring Principal Component Analysis Local Outlier Factor
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Analysis and Response of Steel Stacking Accidents in Hot Rolling Coilers
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作者 Zhenyi Yu Yuan Long Shuqi Tang 《Frontiers of Metallurgical Industry》 2024年第2期10-14,共5页
Through long-term production and maintenance practice,various types of stacking steel in the 2250mm hot rolling coiler of Ma Steel were tracked and analyzed,and the causes of stacking steel were summarized.Cor-respond... Through long-term production and maintenance practice,various types of stacking steel in the 2250mm hot rolling coiler of Ma Steel were tracked and analyzed,and the causes of stacking steel were summarized.Cor-responding measures were formulated to effectively reduce the probability of stacking steel. 展开更多
关键词 COILER stacking steel cause analysis MEASURE
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Workflow logs analysis system for enterprise performance measurement 被引量:1
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作者 Lai Jin(赖瑾) Fan Yushun 《High Technology Letters》 EI CAS 2005年第3期274-279,共6页
Workflow logs that record the execution of business processes offer very valuable data resource for real-time enterprise performance measurement. In this paper, a novel scheme that uses the technology of data warehous... Workflow logs that record the execution of business processes offer very valuable data resource for real-time enterprise performance measurement. In this paper, a novel scheme that uses the technology of data warehouse and OLAP to explore workflow logs and create complex analysis reports for enterprise performance measurement is proposed. Three key points of this scheme are studied: 1) the measure set; 2) the open and flexible architecture for workflow logs analysis system; 3) the data models in WFMS and data warehouse. A case study that shows the validity of the scheme is also provided. 展开更多
关键词 工作流程 日志分析 性能测试 数据库 OLAP
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Morphological Measurement and Analysis of Gymnarchus Niloticus 被引量:10
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作者 Hu Tian-jiang Li Fei Wang Guang-ming Shen Lin-cheng 《Journal of Bionic Engineering》 SCIE EI CSCD 2005年第1期25-31,共7页
Gyrnnarchus niloticus swims by undulations of a long-based dorsal fin, while its body axis is in many cases held straight during swimming. This paper provides a brief relevant introduction to Gyrnnarchus niloticus, wh... Gyrnnarchus niloticus swims by undulations of a long-based dorsal fin, while its body axis is in many cases held straight during swimming. This paper provides a brief relevant introduction to Gyrnnarchus niloticus, which belongs to the African freshwater electric eels but can inspire our bionic interests in propulsion besides its abilities in electric sensing. A special larva of Gyrnnarchus niloticus was morphologically measured by photographing it with a piece of scale-calibrated paper as the background. Then we analyzed the data by a CFD-aided approach. Detailed flow patterns around the larva and a NACA0012 hydrofoil were respectively calculated and visualized at the Reynolds number of 7350 or so. The results show that the profile of Gyrnnarchus niloticus is well streamlined. 展开更多
关键词 BIONIC Gymnarchus niloticus morphological measurement CFD-based analysis streamlined profile
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Uncertainty analysis of flow rate measurement for multiphase flow using CFD 被引量:9
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作者 Joon-Hyung Kim Uk-Hee Jung +2 位作者 Sung Kim Joon-Yong Yoon Young-Seok Choi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第5期698-707,共10页
The venturi meter has an advantage in its use,because it can measure flow without being much affected by the type of the measured fluid or flow conditions.Hence,it has excellent versatility and is being widely applied... The venturi meter has an advantage in its use,because it can measure flow without being much affected by the type of the measured fluid or flow conditions.Hence,it has excellent versatility and is being widely applied in many industries.The flow of a liquid containing air is a representative example of a multiphase flow and exhibits complex flow characteristics.In particular,the greater the gas volume fraction(GVF),the more inhomogeneous the flow becomes.As a result,using a venturi meter to measure the rate of a flow that has a high GVF generates an error.In this study,the cause of the error occurred in measuring the flow rate for the multiphase flow when using the venturi meter for analysis by CFD.To ensure the reliability of this study,the accuracy of the multiphase flow models for numerical analysis was verified through comparison between the calculated results of numerical analysis and the experimental data.As a result,the Grace model,which is a multiphase flow model established by an experiment with water and air,was confirmed to have the highest reliability.Finally,the characteristics of the internal flow Held about the multiphase flow analysis result generated by applying the Grace model were analyzed to find the cause of the uncertainty occurring when measuring the flow rate of the multiphase flow using the venturi meter.A phase separation phenomenon occurred due to a density difference of water and air inside the venturi,and flow inhomogeneity happened according to the flow velocity difference of each phase.It was confirmed that this flow inhomogeneity increased as the GVF increased due to the uncertainty of the flow measurement. 展开更多
关键词 Multiphase flow Measurement Numerical analysis Venturi meter Gas volume fraction(GVF) Uncertainty Multiphase flow model Grace model
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Measurement uncertainty in pharmaceutical analysis and its application 被引量:8
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作者 Marcus Augusto Lyrio Traple Alessandro Morais Saviano +1 位作者 Fabiane Lacerda Francisco Felipe Rebello Lourencon 《Journal of Pharmaceutical Analysis》 CAS 2014年第1期1-5,共5页
The measurement uncertainty provides complete information about an analytical result. This is very important because several decisions of compliance or non-compliance are based on analytical results in pharmaceutical ... The measurement uncertainty provides complete information about an analytical result. This is very important because several decisions of compliance or non-compliance are based on analytical results in pharmaceutical industries. The aim of this work was to evaluate and discuss the estimation of uncertainty in pharmaceutical analysis. The uncertainty is a useful tool in the assessment of compliance or non-compliance of in-process and final pharmaceutical products as well as in the assessment of pharmaceutical equivalence and stability study of drug products. 展开更多
关键词 Measurement uncertainty Method validation Pharmaceutical analysis Quality control
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ONE-WAY MULTIVARIATE REPEATED MEASUREMENTS ANALYSIS OF VARIANCE MODEL 被引量:2
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作者 Abdul-Hussein Saber AL-MOUEL 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第4期435-448,共14页
The one-way multivariate repeated measurements analysis of variance (1-way MRM ANOVA) model for complete data and the sphericity test are studied.
关键词 one-way multivariate repeated measurements analysis of variance likelihood ratio criterion sphericity test asymptotic expansion.
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Fault Detection Based on Hierarchical Cluster Analysis in Wide Area Backup Protection System 被引量:2
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作者 Yagang ZHANG Jinfang ZHANG +1 位作者 Jing MA Zengping WANG 《Energy and Power Engineering》 2009年第1期21-27,共7页
In wide area backup protection of electric power systems, the prerequisite of protection device's accurate, fast and reliable performance is its corresponding fault type and fault location can be discriminated qui... In wide area backup protection of electric power systems, the prerequisite of protection device's accurate, fast and reliable performance is its corresponding fault type and fault location can be discriminated quickly and defined exactly. In our study, global information will be introduced into the backup protection system. By analyzing and computing real-time PMU measurements, basing on cluster analysis theory, we are using mainly hierarchical cluster analysis to search after the statistical laws of electrical quantities' marked changes. Then we carry out fast and exact detection of fault components and fault sections, and finally accomplish fault isolation. The facts show that the fault detection of fault component (fault section) can be performed successfully by hierarchical cluster analysis and calculation. The results of hierarchical cluster analysis are accurate and reliable, and the dendrograms of hierarchical cluster analysis are in intuition. 展开更多
关键词 WIDE area BACKUP protection PHASOR MEASUREMENT unit PMU WIDE area MEASUREMENT system WAMS fault detection cluster analysis
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Manipulations Between Eigenstates of 2-Level Quantum System Based on Optimal Measurements 被引量:1
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作者 Jingbei Yang Shuang Cong +1 位作者 Feng Shuang Herschel Rabitz 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第1期35-41,共7页
This paper explores the manipulation between eigenstates in a two-level system by a sequence of instantaneous projective measurements. Three cases of the manipulations are studied: the manipulation of optimal measurem... This paper explores the manipulation between eigenstates in a two-level system by a sequence of instantaneous projective measurements. Three cases of the manipulations are studied: the manipulation of optimal measurement-based control;the optimal measurement-based manipulation with the effect of free evolution of system; and the external control fields being used to compensate for the effect caused by the free evolution. Numerical simulations are conducted to verify the results obtained from the theoretically analytical solutions. The optimal parameters for each manipulation case are obtained. The experimental results indicate that the external control fields can make the optimal measurement-based control more effective. 展开更多
关键词 Quantum measurement state transfer characteristics analysis
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Radiation Damage Analysis of Individual Subcells for GaInP/GaAs/Ge Solar Cells Using Photoluminescence Measurements 被引量:2
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作者 郑勇 易天成 +2 位作者 王君玲 肖鹏飞 王荣 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第2期63-66,共4页
The radiation damage of three individual subcells for GalnP/GaAs//Ge triple-junction solar cells irradiated with electrons and protons is investigated using photoluminescence (PL) measurements. The PL spectra of eac... The radiation damage of three individual subcells for GalnP/GaAs//Ge triple-junction solar cells irradiated with electrons and protons is investigated using photoluminescence (PL) measurements. The PL spectra of each subcell are obtained using different excitation lasers. The PL intensity has a fast degradation after irradiation, and decreases as the displacement damage dose increases. Furthermore, the normalized PL intensity varying with the displacement damage dose is analyzed in detail, and then the lifetime damage coefficients of the recombination centers for GaInP top-cell, GaAs mid-cell and Ge bottom-cell of the triple-junction solar cells are determined from the PL radiative efficiency. 展开更多
关键词 Radiation Damage Analysis of Individual Subcells for GaInP/GaAs/Ge Solar Cells Using Photoluminescence Measurements Ge
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Spectrum Occupancy Measurement and Analysis 被引量:1
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作者 Tian Fang 1 , Feng Zhiyong 1 , Chen Xing 2 (1 . Beijing University of Posts and Telecommunications , Beijing 100876 , P . R . China 2 . Research Institution of China Mobile Communications Corporation , Beijing 100053 , P . R . China ) 《ZTE Communications》 2009年第2期16-20,共5页
This paper analyzes current spectrum utilization from all aspects based on related methods of spectrum measurement. The measurement results show that some spectrum resources are not used effectively due to current fix... This paper analyzes current spectrum utilization from all aspects based on related methods of spectrum measurement. The measurement results show that some spectrum resources are not used effectively due to current fixed spectrum allocation policy, and the spectrum occupancy varies dramatically in terms of time and space. These results provide basis for the development of next generation wireless communication technologies such as Cognitive Radio (CR). 展开更多
关键词 Spectrum Occupancy Measurement and Analysis FIGURE RADIO
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Mechanical Analysis and Measurements of a Multicomponent NbTi/Cu Superconducting Magnets Structure for the Fully Superconducting Electron Cyclotron Resonance Ion Source 被引量:1
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作者 关明智 胡强 +6 位作者 高配峰 王省哲 杨通军 吴巍 辛灿杰 吴北民 马力祯 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期135-139,共5页
A fully superconducting electron cyclotron resonance (ECR) ion source (SECRAL ID is currently being built in the Institute of Modern Physics, Chinese Academy of Sciences. Its key components are three superconductin... A fully superconducting electron cyclotron resonance (ECR) ion source (SECRAL ID is currently being built in the Institute of Modern Physics, Chinese Academy of Sciences. Its key components are three superconducting solenoids (Nb-Ti/Cu) and six superconducting sextupoles (Nb-Ti/Cu). Different from the conventional supercon- ducting ECR magnetic structure, the SEC17AL Ⅱ includes three superconducting solenoid coils' that are located inside the superconducting sextupoles. The SECRAL Ⅱ can significantly reduce the interaction forces between the sextupole and the solenoids, and the magnets can also be more compact in size. For this multi-component SECRAL Ⅱ generating its self field of -8 T and being often exposed to the high self field, the mechanical analysis has become the main issue to keep their stress at 〈200 MPa on coils. The analytical and experimental results in mechanics are presented in the SECRAL Ⅱ structure. To improve the accuracy and efficiency of analysis, according to the composite rule of micromechanics, the equivalent uniform windings are used to simulate the epoxy-impregnated Nb-Ti/Cu coils. In addition, using low temperature strain gauges and a wireless fast strain acquisition system, a fundamental experiment on the based on our analysis, the stresses and deformations optimized. strains developments of a sextupole is reported. Finally, for its assembly of each SECRAL Ⅱ coil will be further 展开更多
关键词 of on IS as NBTI Mechanical Analysis and Measurements of a Multicomponent NbTi/Cu Superconducting Magnets Structure for the Fully Superconducting Electron Cyclotron Resonance Ion Source in for Cu
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Flux measurements for a DD neutron generator using neutron activation analysis
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作者 Walid A. Metwally Samar El-Sayed +2 位作者 Ahmad Ababneh David L. Williams Allan X. Chen 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第4期66-71,共6页
The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fa... The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fast neutron fluxes were found to be 2.960 × 10~6 and6.186 × 10~7 n/cm^2 s, respectively. This was done to verify the modeling results for the optimum moderator thickness needed to maximize the thermal neutron flux. The optimum moderator thickness was found to be between 3.5 and4 cm. The present data were compared with the detailed MCNP model-based calculation performed in earlier work to simulate the generator. 展开更多
关键词 NEUTRON ACTIVATION analysis NEUTRON GENERATOR NEUTRON moderation THERMAL NEUTRON FLUX measurement
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Comparative Analysis on Two Kinds of Measurement Methods of Particulate Matters in Waste Gas of Low Velocity
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作者 Li Weijun Ji Guangjun +2 位作者 Yang Xianglin Zhang Xingyao Jing Yifeng 《Meteorological and Environmental Research》 CAS 2019年第5期70-73,共4页
In the current waste gas sampling of fixed source,it is required that deviation of tracking rate of constant velocity sampling should not be more than 10%.When flow rate of the waste gas is less than 5 m/s,the trackin... In the current waste gas sampling of fixed source,it is required that deviation of tracking rate of constant velocity sampling should not be more than 10%.When flow rate of the waste gas is less than 5 m/s,the tracking rate can not meet this requirement.The sampling of fixed velocity can meet the requirement of particulate matter sampling on gas collection volume at low velocity.Through the comparison of two different methods for the determination of particulate matter in waste gas under the low flow velocity of flue gas,it was found that there were some differences between the fixed velocity measurement and the constant velocity measurement.The results showed that measurement result of the fixed velocity was higher than that of constant velocity measurement under low velocity.At the same time,the deviation of fixed velocity measurement was not obvious under different low velocity. 展开更多
关键词 LOW flow VELOCITY PARTICULATE MATTER Measurement COMPARATIVE analysis
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MEASUREMENT AND CORRELATIVE ANALYSIS OF THE ADULT CHINESE MANDIBULAR ARCHES
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作者 孙大麟 徐丽丽 刘善学 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1991年第2期103-106,共4页
One hundred fifty three mandibles of adult Chinese cadavers were measured. The acquired data were correlatively analysed with computer. It was found that bigonial breadth (EE’) was correlated with the breadth between... One hundred fifty three mandibles of adult Chinese cadavers were measured. The acquired data were correlatively analysed with computer. It was found that bigonial breadth (EE’) was correlated with the breadth between bilateral canines (BB’), the bimentalbreite (CC’) and the breadth between right and left vertex of alveolar ridge between the first and the second molar (DD’). The length of mandibular body (AF) was strongly correlated with the vertical distance from bigonial breadth to the breadth of bilateral canines (BB’F), to the bimentalbreite (CC’F) and to the breadth between right and left vertex of alveolar ridge between the first and the second molar (DD’F). Six regressive equations were established. Significance of these equations was discussed. 展开更多
关键词 MANDIBLE MEASUREMENT REGRESSIVE analysis
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