Test of very fast kicker for TESLA damping ring

We describe a very fast kicker with unique combination of high repetition rate and short pulse width. Constructionally, the device is a symmetrical counter traveling wave stripline kicker fed by semiconductor high-voltage pulse generator. Experimentally tested kicker has a full pulse width of about 7 ns, 1.4 MHz repetition rate and maximum kick strength of the order of 3 G{center_dot}m. Recent achievements in high-voltage semiconductor field-effect transistors (FET) technology and goal-specific optimization of the kicker parameters allow many-fold increase of the strength, and the kicker can be very useful tool for bunch-by-bunch injection/extraction and other accelerator applications. 4 refs., 3 figs

Extracellular histones are essential effectors of C5aR‐ and C5L2‐mediated tissue damage and inflammation in acute lung injury

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154331/1/fsb2027012034.pd

Efficient memory management in video on demand servers

In this article we present, analyse and evaluate a new memory management technique for video-on-demand servers. Our proposal, Memory Reservation Per Storage Device (MRPSD), relies on the allocation of a fixed, small number of memory buffers per storage device. Selecting adequate scheduling algorithms, information storage strategies and admission control mechanisms, we demonstrate that MRPSD is suited for the deterministic service of variable bit rate streams to intolerant clients. MRPSD allows large memory savings compared to traditional memory management techniques, based on the allocation of a certain amount of memory per client served, without a significant performance penaltyPublicad

Traveling to Rome: QoS specifications for automated storage system management

. The design and operation of very large-scale storage systems is an area ripe for application of automated design and management techniques -- and at the heart of such techniques is the need to represent storage system QoS in many guises: the goals (service level requirements) for the storage system, predictions for the design that results, enforcement constraints for the runtime system to guarantee, and observations made of the system as it runs. Rome is the information model that the Storage Systems Program at HP Laboratories has developed to address these needs. We use it as an "information bus" to tie together our storage system design, configuration, and monitoring tools. In 5 years of development, Rome is now on its third iteration; this paper describes its information model, with emphasis on the QoS-related components, and presents some of the lessons we have learned over the years in using it. 1

Efficient Bulk Operations on Dynamic R-Trees

In recent years there has been an upsurge of interest in spatial databases. A major issue is how to manipulate efficiently massive amounts of spatial data stored on disk in multidimensional spatial indexes (data structures). Construction of spatial indexes (bulk loading) has been studied intensively in the database community. The continuous arrival of massive amounts of new data makes it important to update existing indexes (bulk updating) efficiently. In this paper we present a simple, yet efficient, technique for performing bulk update and query operations on multidimensional indexes. We present our technique in terms of the so-called R-tree and its variants, as they have emerged as practically efficient indexing methods for spatial data. Our method uses ideas from the buffer tree lazy buffering technique and fully utilizes the available internal memory and the page size of the operating system. We give a theoretical analysis of our technique, showing that it is efficient both in terms of I/O communication, disk storage, and internal computation time. We also present the results of an extensive set of experiments showing that in practice our approach performs better than the previously best known bulk update methods with respect to update time, and that it produces a better quality index in terms of query performance. One important novel feature of our technique is that in most cases it allows us to perform a batch of updates and queries simultaneously. To be able to do so is essential in environments where queries have to be answered even while the index is being updated and reorganized