可编程光衰减器的设计方法

随着数据率的增加和比较大的中继器间距,对光纤传输系统的要求越来越严格,而且容限己经变得最小。特别是在光学方面的比较好的测试设备是很需要的,以用于测量和保证技术指标。同时,对高性能传输设备的要求也在迅速增长,必须建立生产能力和产生测试程序。为了满足这一要求,必须缩短测试时     

RESONANT PHOTOEMISSION OF BULK CeO2 AND NANO—CeO2 FILMS

Photoemission behaviors of nano-CeO2 films with parlicle sizes ranging from 8nm to 50nm and bulk CeO2 in Ce 4d-4f absorption region have been investigated.Resonant enhancements of Ce 4f valance band and Ce 5p bands for nano film and bulk material have been observed.The variation of electron density of Ce 4d-4f resonace.     

The BTeV DAQ and Trigger System—Some Throughput,Usability and Fault Tolerance Aspects

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.     

Critical Internuclear Separation of H+2 in Strong Light Field of Ti:s Laser

Image method was employed to study the ionization and dissociation behaviors of molecular hydrogen ions in the presence of strong Ti:s laser light. Besides the bond-softening and above-threshold dissociation phenomena, we found that the critical internuclear separation in Coulomb explosion process was dependent upon light intensity. The experimental and theoretical trends of this dependence were shown to be in a fairly good agreement. The light intensity range used was 1014～1016 W/cm2.     

CMS Grid Activities in Europe

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.     

生物圈代谢增强: 对一项观测数据的分析结果

运用Ｈａｌｌ等人的研究方法，对大气二氧化碳浓度，化石能源燃烧释放，以及 海洋ＣＯ_2吸收等数据进行分析，得到自１９５８～１９９２年间北半球生态系统的生产量和呼 吸量的变化．分析表明，从１９５８～１９７２年的１５年间，生物圈的生产量和呼吸量没有明 显改变；然而，两者自从７０年代初以来却有明显提高，其提高幅度在北半球的高纬度 地区较为显著，而南半球的净初级生产和异养呼吸大体保持不变．在具有观测数据的 ３５年间，生产量和呼吸量的比率基本保持不变；换言之，全球生物圈正在提高其转化 率和代谢率．     

Von Neumann Regularity and Quadratic Conorms in JB^＊-triples and C^＊-algebras

We revise the notion of von Neumann regularity in JB^＊-triples by finding a new characterisation in terms of the range of the quadratic operator Q（a）. We introduce the quadratic conorm of an element a in a JB^＊-triple as the minimum reduced modulus of the mapping Q（a）. It is shown that the quadratic conorm of a coincides with the infimum of the squares of the points in the triple spectrum of a. It is established that a contractive bijection between JBW^＊-triples is a triple isomorphism if, and only if, it preserves quadratic conorms. The continuity of the quadratic conorm and the generalized inverse are discussed. Some applications to C^＊-algebras and von Neumann algebras are also studied.     

What's new with the XYZ mesons?

I review some of the recent experimental results on the so-called XYZ mesons.     

Fermilab Distributed Monitoring System（NGOP）

A Distributed Monitoring System(NGOP)that will scale to the anticipated requirements for RUn II computing has been under development at Fermilab.NGOP [1] provides a framework to create Monitoring Agents for monitoring the overall state of computers and software that are running on them.Several Monitoring Agents are available within NGOP that are capable of analyzing log files,and checking existence of system daemons,CPU and memory utilization,etc,NGOP also provides customizable graphical hierarchical representations of these monitored systems.NGOP is able to generate events when serious problems have occurred as well as raising alarms when potential problems have been detected.NGOP allows performing correctiv actions or sending notifications,NGOP provides persistent storage for collected events,alarms and actions.A first implementation of NGOP was recently deployed at Fermilab.This is a fully functional prototype that satisfies most of the existing requirements.For the time being the NGOP prototype is monitoring 512 nodes.During the first few months of running NGOP has proved to be a useful tool.Multiple problems such as node resets,offline CPUs,and dead system daemons have been detected.NGOP provided system administrators with information required for better system tuning and configuration.The current state of deployment and future steps to improve the prototype and to implement some new features will be presented.