检索结果-内蒙古大学图书馆

2010 ieee International symposium on parallel and distributed processing, Workshops and Phd Forum, IPDPSW 2010

作者： Misra, Sanchit Narayanan, Ramanathan Liao, Wei-Keng Choudhary, Alok Lin, Simon Department of Electrical Engineering and Computer Science Northwestern University Evanston IL 60208 United States Robert H. Lurie Comprehensive Cancer Center Northwestern University Chicago IL 60611 United States

ISBN: (纸本)9781424465347

Millions of DNA sequences (reads) are generated by Next Generation Sequencing machines everyday. there is a need for high performance algorithms to map these sequences to the reference genome to identify single nucleotide polymorphisms or rare transcripts to fulfill the dream of personalized medicine. In this paper, we present a high-throughput parallel sequence mapping program pFANGS. pFANGS is designed to find all the matches of a query sequence in the reference genome tolerating a large number of mismatches or insertions/ deletions. pFANGS partitions the computational workload and data among all the processes and employs loadbalancing mechanisms to ensure better process efficiency. Our experiments show that, with 512 processors, we are able to map approximately 31 million 454/Roche queries of length 500 each to a reference human genome per hour allowing 5 mismatches or insertion/deletions at full sensitivity. We also report and compare the performance results of two alternative parallel implementations of pFANGS: a shared memory OpenMP implementation and a MPI-OpenMP hybrid implementation.© 2010 ieee.

关键词： DNA sequences

来源：评论

学校读者我要写书评

暂无评论

Reliability analysis of declustered-parity RAID 6 with disk scrubbing and considering Irrecoverable Read Errors

Reliability analysis of declustered-parity RAID 6 with disk ...

引用

5th ieee International Conference on Networking, Architecture and Storage, NAS 2010

作者： Gao, Yan Meister, Dirk Brinkmann, André University of Paderborn Paderborn Center for Parallel Computing Fuerstenallee 11 33102 Paderborn Germany

ISBN: (纸本)9780769541341

We investigate the impact of Irrecoverable Read Errors (IREs) on Mean Time To Data Loss (MTTDL) of declustered-parity RAID 6 systems. By extending the analytic model to study the reliability of RAID 5 systems from [1] we obtain the MTTDL which mainly takes into account two types of data loss: data loss caused by three independent disk failures, and data loss due to a detected IRE during the rebuild after two disks failed. Furthermore we improve the analysis by also considering disk scrubbing to reduce the probability of IREs via periodically reading the data stored on a disk. the results of our numerical analysis show that IREs have a large effect on the MTTDL. the countermeasure is to increase the disk scrubbing rate. As an example, the MTTDL of a system where each disk is scrubbed everyday increases by a factor of at least 27 compared to that of a system with a scrubbing rate of once a year. In addition, declustered-parity RAID 6 system improves the reliability of standard non-declustered RAID 6 systems. For example, a declustered-parity RAID 6 system without disk scrubbing improves the MTTDLs by a factor at least 150 compared to that of a standard system where each disk is scrubbed everyday. © 2010 ieee.

关键词： Errors

来源：评论

学校读者我要写书评

暂无评论

parallel computation of best connections in public transportation networks

Parallel computation of best connections in public transport...

引用

24th ieee International parallel and distributed processing symposium, IPDPS 2010

作者： Delling, Daniel Katz, Bastian Pajor, thomas Microsoft Research Silicon Valley 1065 La Avenida Mountain View CA 94043 United States Department of Computer Science Karlsruhe Institute of Technology 76128 Karlsruhe Germany

ISBN: (纸本)9781424464432

Exploiting parallelism in route planning algorithms is a challenging algorithmic problem with obvious applications in mobile navigation and timetable information systems. In this work, we present a novel algorithm for the so- called one-to-all profile-search problem in public transportation networks. It answers the question for all fastest connections between a given station S and any other station at any time of the day in a single query. this algorithm allows for a very natural parallelization, yielding excellent speed- ups on standard multi-core servers. Our approach exploits the facts that first, time-dependent travel-time functions in such networks can be represented as a special class of piecewise linear functions, and that second, only few connections from S are useful to travel far away. Introducing the connection- setting property, we are able to extend DlJKSTRA's algorithm in a sound manner. Furthermore, we also accelerate station-to- station queries by preprocessing important connections within the public transportation network. As a result, we are able to compute all relevant connections between two random stations in a complete public transportation network of a big city (Los Angeles) on a standard multi-core server in less than 55 ms on average. © 2010 ieee.

关键词： Travel time

来源：评论

学校读者我要写书评

暂无评论

A scalable algorithm for maintaining perpetual system connectivity in dynamic distributed systems

A scalable algorithm for maintaining perpetual system connec...

引用

24th ieee International parallel and distributed processing symposium, IPDPS 2010

作者： Bansal, Tarun Mittal, Neeraj Department of Computer Science Ohio State University Columbus OH 43202 United States Department of Computer Science University of Texas Dallas Richardson TX 75080 United States

ISBN: (纸本)9781424464432

We investigate the problem of maintaining a topology with small degree as well as small diameter in a dynamic distributed system such that the system always stays connected and processes that wish to leave the system can do so quickly. Perpetual system connectivity is necessary to solve many important problems in dynamic distributed systems, including atomic broadcast and stable property detection, that need strict (deterministic) guarantees about system connectivity to be solvable. To our knowledge, in all existing topology maintenance algorithms for asynchronous distributed systems that provide perpetual system connectivity, either: (i) the topology has large worst-case degree and/or diameter (ii) a process may experience high worst-case delay when leaving the system, or (iii) processes cannot join and/or leave concurrently. In this paper, we present a spanning tree maintenance algorithm that satisfies the following desirable properties. First, the spanning tree has small maximum degree of O(1) and small maximum diameter of O(log N), where N denotes the maximum size of the system. Second, any process can leave the system within O(log N) time even in the presence of concurrent arrivals and departures. third, the system always stays connected. We show using a simple knowledge-based argument that, in any algorithm that maintains perpetual connectivity such that the topology has either worst-case diameter of fi(log N) or worst-case degree of O(1), the departure of a process may be delayed by fi(log log N) time in the worst-case. ©2010 ieee.

关键词： Trees (mathematics)

来源：评论

学校读者我要写书评

暂无评论

An effective hybrid energy storage system based on battery-EDLC for distributed generation systems

An effective hybrid energy storage system based on battery-E...

引用

5th ieee Conference on Industrial Electronics and Applications, ICIEA 2010

作者： Jiancheng, Zhang Liantao, Ji Department of Electrical Engineering North China Electric Power University Baoding China

ISBN: (纸本)9781424450466

All stand-alone distributed generation systems require an energy buffer to bridge the mismatch between available and required energy. the lead acid battery, which has a high energy density, is the most popular form of energy storage utilized. Nevertheless, it is impossible to supply the load with an instantaneous large power, due to its low power density. Accordingly, in this paper, a new hybrid energy storage system which is composed of battery and electrical double layer capacitor (EDLC) connected in parallel is established, it could make the best use of the characteristics of high energy density of battery and high power density, long circle life of EDLC. A buck and a bi-directional converter are also proposed to charge the battery and the EDLC with an additional function to stabilize the DC bus voltage. In comparison with the battery alone energy storage system, the proposed scheme can significantly improve the performance of the distributed generation system, enhance the energy using efficiency and reduce the battery capacity. Furthermore, the life of the battery can be lengthened for the reduced charging/recharging frequency of the battery when the generated power and the load power vary quickly. the high stability and high efficiency of the proposed system is verified through simulation and experiment results under various conditions. © 2010 ieee.

关键词： Energy storage

来源：评论

学校读者我要写书评

暂无评论

Mobility control for achieving optimal configuration in wireless sensor networks

引用

WIRELESS NETWORKS 2010年第1期16卷 141-152页

作者： Jiang, Zhen Wu, Jie Kline, Robert W Chester Univ Dept Comp Sci Informat Secur Ctr W Chester PA 19383 USA Florida Atlantic Univ Dept Comp Sci & Engn Boca Raton FL 33431 USA

Recent work in wireless sensor networks, or simply called WSNs, has drawn attention to the mobility capability of each node. In Stojmenovic and Lin (ieee Trans parallel Distrib Syst 12: 1023-1032, 2001). it is proved that the optimal positions of the relay nodes along a active flow must lie entirely oil the line between the source and destination with each node spaced evenly along such a line. Based oil this, we propose two practical solutions to control the relay nodes in WSNs to approach their optimal positions in the local relative coordinate system. One uses one-hop neighbor information and the other one uses two-hop neighbor information. Basically, each relay node will approach the midpoint oil the line composed of neighbors. For the latter control scheme, we also discuss Its different implementation with outdated two-hop neighbor information (lagged by one-round neighbor information exchange and update). this is all improvement since given nodes only reuse the two-hop neighbor information previously saved at its one-hop neighbors and does not require any extra neighbor information collection. All the new methods prevent oscillations by demanding minimal moving distance per round (MDPR), otherwise the node does not move. Unlike the one presented in Goldenberg et in. (proceedings of the 5th ACM International symposium Oil Mobile Ad Hoc Networking and Computing (Mobihoc'04), pp 163-174 2004) using Only one-hop neighbor information. Our methods win converge more quickly. the experimental results Show a Substantial improvement oil the speed of,achieving the optimal Configuration and the total moving distance of nodes.

关键词： Wireless sensor networks (WSNs) distributed algorithm Information model Mobility control Self-configuration

来源：评论

学校读者我要写书评

暂无评论

parallel electromagnetic simulation for electric large target by EMS-FMM

Parallel electromagnetic simulation for electric large targe...

引用

5th International Conference on Frontier of Computer Science and Technology, FCST 2010

作者： Wang, Wu Feng, Yangde Chi, Xuebin Supercomputing Center Computer Network Information Center CAS Beijing 100190 China Graduate University Chinese Academy of Sciences Beijing 100049 China

ISBN: (纸本)9780769541396

the development framework of parallel electromagnetic simulation software EMS-FMM based on multilevel fast multipole method (MLFMM) is present in this paper. EMS-FMM can solve large-scale scattering problem of 10 million scale with a complexity of ο(N log N), so it's efficient for electric large target. It's implemented by C and Fortran with MPI communication on cluster DeepComp 7000. Implementation of MLFMM, interpolation algorithm for sphere functions, load balance and communication scheme for distributed octree structure are also discussed. the results demonstrate that surface current and radar cross section (RCS) of large complex target, such as plane and destroyer models, can be calculated by EMS-FMM. © 2010 ieee.

关键词： Electromagnetic simulation

来源：评论

学校读者我要写书评

暂无评论

parallel de novo assembly of large genomes from high-throughput short reads

Parallel de novo assembly of large genomes from high-through...

引用

24th ieee International parallel and distributed processing symposium, IPDPS 2010

作者： Jackson, B.G. Regennitter, M. Yang, X. Schnable, P.S. Aluru, S. Department of Electrical and Computer Engineering Iowa State University Ames IA United States Department of Agronomy Iowa State University Ames IA United States

ISBN: (纸本)9781424464432

the advent of high-throughput short read technology is revolutionizing life sciences by providing an inexpensive way to sequence genomes at high coverage. Exploiting this technology requires the development of a de novo short read assembler, which is an important open problem that is garnering significant research effort. Current methods are largely limited to microbial organisms, whose genomes are two to three orders of magnitude smaller than complex mammalian and plant genomes. In this paper, we present the design and development of a parallel de novo short read assembler that can scale to large genomes with high coverage. Our approach is based on the string graph formulation. Input reads are mapped to short paths, and the genome is reconstructed as a superpath anchored by distance constraints inferred from read pairs. Our method can handle a mixture of multiple read sizes and multiple paired read distances. We present parallel algorithms for string graph construction, string graph compaction, graph based error detection and removal, and computing aggregate summarization of paired read links across graph edges. Using this, we navigate the final graph structure to reproduce large contiguous sequences from the underlying genome. We present a validation of our framework on experimental and simulated data from multiple known genomes and present scaling results on IBM Blue Gene/L. © 2010 ieee.

关键词： Mammals

来源：评论

学校读者我要写书评

暂无评论

A high data rate parallel demodulator suited to FPGA implementation

A high data rate parallel demodulator suited to FPGA impleme...

引用

18th International symposium on Intelligent Signal processing and Communication Systems, ISPACS 2010

作者： Lin, Changxing Shao, Beibei Zhang, Jian Department of Engineering Physics Tsinghua University Beijing China Institute of Electronic Engineering China Academy of Engineering Physics Mianyang China

ISBN: (纸本)9781424473717

the architecture of high data-rate parallel demodulator suitable for demodulating high order QAM modulated signal and easy to implement on FPGA platform is presented in this paper. the parallel architecture is based on frequency-domain implementation of matched filter and timing phase correction, which was first reported in Alternate parallel Receiver (APRX). O&M timing error estimator based dual parallel feedback loop is proposed for timing recovery, while a kind of reduced constellation phase-frequency detector based parallel decision feedback PLL is designed for carrier recovery, their parallel implementation structures suitable for FPGA platform are also investigated. A demonstrate of 5Gbps demodulator for 64QAM modulation is given, fixed point simulation shows that this architecture can efficiently work with performance loss less than IdB. © 2010 ieee.

关键词： Field programmable gate arrays (FPGA)

来源：评论

学校读者我要写书评

暂无评论

Adaptive sampling-based profiling techniques for optimizing the distributed JVM runtime

Adaptive sampling-based profiling techniques for optimizing ...

引用

24th ieee International parallel and distributed processing symposium, IPDPS 2010

作者： Lam, King Tin Luo, Yang Wang, Cho-Li Department of Computer Science University of Hong Kong Hong Kong Hong Kong

ISBN: (纸本)9781424464432

Extending the standard Java virtual machine (JVM) for cluster-awareness is a transparent approach to scaling out multithreaded Java applications. While this clustering solution is gaining momentum in recent years, efficient runtime support for fine-grained object sharing over the distributed JVM remains a challenge. the system efficiency is strongly connected to the global object sharing profile that determines the overall communication cost. Once the sharing or correlation between threads is known, access locality can be optimized by collocating highly correlated threads via dynamic thread migrations. Although correlation tracking techniques have been studied in some page-based sof Tware DSM systems, they would entail prohibitively high overheads and low accuracy when ported to fine-grained object-based systems. In this paper, we propose a lightweight sampling-based profiling technique for tracking inter-thread sharing. To preserve locality across migrations, we also propose a stack sampling mechanism for profiling the set of objects which are tightly coupled with a migrant thread. Sampling rates in both techniques can vary adaptively to strike a balance between preciseness and overhead. Such adaptive techniques are particularly useful for applications whose sharing patterns could change dynamically. the profiling results can be exploited for effective thread-to-core placement and dynamic load balancing in a distributed object sharing environment. We present the design and preliminary performance result of our distributed JVM with the profiling implemented. Experimental results show that the profiling is able to obtain over 95% accurate global sharing profiles at a cost of only a few percents of execution time increase for fine- to medium- grained applications. © 2010 ieee.

关键词： Virtual machine

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：