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11.
Effects of Wall Ablation on the Trigger Process in Two—Gap Capillary Plasma Generator 总被引:1,自引:0,他引:1 下载免费PDF全文
XIASheng-Guo LIUKe-Fu PANYuan HUXi-Wei 《中国物理快报》2003,20(6):873-876
Two-gap capillary plasma generator is a realistic alternative to the conventional capillary in electrothermal launchers. It is designed to accomplish two goals: repetitive operation and a compact power supply system in which capillary itself serves as a closing switch. A theoretical model is proposed to investigate the trigger process of this kind of generator. Both ablation case and no ablation case are considered. Trigger delay time is also theoretically analysed. The calculation shows that capillary wall ablation can greatly change the behaviour of trigger discharge arc and plasma flow generated. Trigger delay time can be drastically shortened. 相似文献
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As presented at the last CHEP conference,the BTeV triggering and data collection pose a significant challenge in construction and operation,generating 1.5 Terabytes/second of raw data from over 30 million detector channels.We report on facets of the DAQ and trigger farms.We report on the current design of the DAQ,especially its partitioning features to support commissioning of the detector.We are exploring collaborations with computer science groups experienced in fault tolerant and dynamic real-time and embedded systems to develop a system to provide the extreme flexibility and high availability required of the heterogeneous trigger farm(-ten thousand DSPs and commodity processors).We describe directions in the following areas:system modeling and analysis using the Model Integrated Computing approach to assist in the creation of domain-specific modeling,analysis,and program synthesis environments for building complex,large-scale computer-based systems;System Configuration Management to include compileable design specifications for configurable hardware components,schedules,and communication maps. Runtime Environment and Hierarchical Fault Detection/Management-a system-wide infrastructure for rapidly detecting,isolating,filtering,and reporting faults which will be encapsulated in intelligent active entites(agents)to run on DSPs,L2/3 processors,and other supporting processors throughout the system. 相似文献
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The CMS experiment at the CERN LHC collider is producing large amounts of simulated data in order to provide an adequate statistic for the Trigger System design.These productions are performed in a distributed environment,prototyping the hierarchical model of LHC computing centers developed by MONARC.A GRID approach is being used for interconnecting the Regional Centers.The main issues which are currently addressed are:automatic submission of data production requests to available productioin sites,data transfer among production sites,“best-replica” location and submission of enduser analysis job to the appropriate Regional Center,In each production site different hardware configurations are being tested and exploited.Furthermore robust job submission systems.which are also able to provide the needed bookkeeping of the produced data are being developed.BOSS(Batch Object Submission System)is an interface to the local computing center scheduling system that has been developed in order to allow recording in a relational database of information produced by the jobe running on the batch facilities A summary of the current activites and a plan for the use of DataGrid PM9 tools are presented. 相似文献
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针对近几年来,我校所招新生基础普遍较差的实际,本人在物理教学中,打破常规做法,在职业医学生中实施“异步调控教学法”,收到了较好的效果,就此谈点体会和做法.1正确区分职业医学生中的不同情况首先,要对新生调查摸底,然后进行分类,学习基础各方面能力都比较好... 相似文献
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叙述了七路输出高电压脉冲触发装置的基本原理、结构和实验结果。该装置输出脉冲幅值可调,可以七路输出最大幅值80kV(1kΩ负载),前沿陡度大于2TV/s,脉宽200ns,时间抖动(σ)小于2ns。 相似文献
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针对主电极间距20 mm以上的沿面击穿型多棒极触发真空开关(TVS),研制了开关触发源。触发源利用脉冲变压器产生脉冲高压输出,在脉冲变压器高压侧并联小容值电容并在电容后串联陡化间隙。陡化间隙的加入可以使触发源输出不受触发沿面金属蒸气沉积的影响。通过调节间隙击穿电压也可以提高电容充电电压及储存能量,从而增加TVS触发沿面被击穿时注入到其中的触发能量。使用该触发源对TVS进行导通实验,结果表明,加入陡化间隙后的触发源输出能量大幅提高且不受触发沿面金属蒸气沉积的影响,能够实现TVS的100%可靠导通。 相似文献
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针对直线脉冲变压器对低电感、低抖动气体开关的研制需要,采用垂直布放的平板轨道电极,组成具有通视结构的水平间隙,设计了一种多间隙轨道式气体开关。利用Meek击穿判据计算了单间隙自击穿电压,实测了4个单间隙的自击穿电压及其相对标准偏差,并根据单间隙自击穿电压,利用概率分析方法预测了多间隙开关自击穿电压,计算值与实测结果一致。研究表明:开关电感最大约109 nH,自击穿电压相对标准偏差为1.5%,在60 kV触发电压和48%~74%欠压比下,开关抖动0.9~2.6 ns。与圆环形电极的多间隙气体开关相比,多间隙轨道式气体开关自击穿电压更稳定,也更容易触发。 相似文献