叠前深度偏移中的旅行时并行计算技术

旅行时计算技术是基于波动方程叠前深度偏移方法的核心内容，射线跟踪的数值计算精度和效率直接影响着介质成像质量和实用化。基于三维射线跟踪的微变网络方法和波前重建思路，提出一种适用于三维复杂介质地震波走时的快速算法。但它所需计算量巨大。采用并行计算技术，设计出基于“任务缓冲池”的动态负载平衡策略，在现有的分布式计算机上，实现了三维射线追踪和叠前深度偏移的并行计算。     

Network and device-level impacts: performance and reliability of active I/O storage systems

Distributed active storage architectures are designed to offload user-level processing to the peripheral from the host servers. In this paper, we report preliminary investigation on performance and fault recovery designs, as impacted by emerging storage interconnect protocols and state-of-the-art storage devices. Empirical results obtained using validated device-level and interconnect data demonstrate the significance of the said parameters on the overall system performance and reliability.     

Optimal biocompatible solvent design for a two-stage extractive fermentation process with cell recycling

In this study, crisp and fuzzy multiple-goal optimization approaches are respectively introduced to design an optimal biocompatible solvent to a two-stage extractive fermentation with cell recycling for ethanol production. When designing a biocompatible solvent for the extractive fermentation process, many issues, such as extractive efficiency, conversion, amount of solvent utilized and so on, have to be considered. An interactive multiple-goal design procedure is introduced to determine a trade-off result in order to satisfy such contradicted goals. Both approaches could be iterated to solve the interactive multiple-goal design problem in order to yield a trade-off result. However, the crisp optimization design is a tedious task that requires the designer to provide various pairs of the upper bounds for the design problem to obtain the corresponding solution. The fuzzy optimization approach is able to be trade-off several goals simultaneously and to yield the overall satisfactory grade for the product/process design problem.     

An efficient parallel strategy for the perfect domination problem on distance-hereditary graphs

A graph is distance-hereditary if the distance stays the same between any of two vertices in every connected induced subgraph containing both. Two well-known classes of graphs, trees and cographs, both belong to distance-hereditary graphs. In this paper, we first show that the perfect domination problem can be solved in sequential linear-time on distance-hereditary graphs. By sketching some regular property of the problem, we also show that it can be easily parallelized on distance-hereditary graphs.     

A Standard Model-Theoretic Approach to Operational Semantics of Recursive Programs

In this paper we try to introduce a new approach to operational semantics of recursive programsby using ideas in the“priority method”which is a fundamental tool in Recursion Theory.In lieu ofmodelling partial functions by introducing undefined values in a traditional approach,we shall define apriority derivation tree for every term,and by respecting the rule“attacking the subterm of thehighest priority first”we define transition relations,computation sequences etc.directly based on astandard interpretation which includes no undefined value in its domain.Finally,we prove that ournew approach generates the same operational semantics as the traditional one.It is also pointed outthat we can use our strategy to refute a claim of Loeckx and Sieber that the opperational semanticsof recursive programs cannot be built based on predicate logic.     

K-Dimensional Optimal Parallel Algorithm for the Solution of a General Class of Recurrence Equations

1IntroductionAlgorithmshavebeenproposedtosolvelinearrecurrencesinparallell1-13].Someofthemsupposeunlimitednumberofprocessorsbeingusedwhileothersuselimitednumberofprocessors.P-M.KoggeandH.S.Stoneproposedarecursivedou-blingalgorithmforthesolutionofageneraJclassofrecuxrenceequationsl1].Itisthefastestalgorithm(thetimeisO(log,N))whenthenumberofprocessingelemelltspiseqllaltoN.Howeveritisnotoptimalintermsofefficiency:itsspeedupisO(de),whileitsefficiencyisO(wt).TherecursivedoublingapproachcanPro…     

水轮机电液调速器人工失灵区的分析计算

本文对电液调速器的人工失灵区电路进行定量分析，导出了失灵区的一套计算公式，并指出失灵区与调差率、功率偏差的内在关系。     

A region-based selective optical flow back-projection for genuine motion vector estimation

Motion vector plays one significant feature in moving object segmentation. However, the motion vector in this application is required to represent the actual motion displacement, rather than regions of visually significant similarity. In this paper, region-based selective optical flow back-projection (RSOFB) which back-projects optical flows in a region to restore the region's motion vector from gradient-based optical flows, is proposed to obtain genuine motion displacement. The back-projection is performed based on minimizing the projection mean square errors of the motion vector on gradient directions. As optical flows of various magnitudes and directions provide various degrees of reliability in the genuine motion restoration, the optical flows to be used in the RSOFB are optimally selected based on their sensitivity to noises and their tendency in causing motion estimation errors. In this paper a deterministic solution is also derived for performing the minimization and obtaining the genuine motion magnitude and motion direction.     

Analysis of a conjugated infinite element method for acoustic scattering

This work is devoted to a study of a conjugated infinite element method for Helmholtz problems in exterior domains. A formulation of this method with Lagrange multipliers defined on (semi-)infinite space is presented and analyzed in a domain decomposition context. The implementation aspects of this method in a parallel industrial acoustic software (SYSNOISE) are described in details. Numerical results show the computational efficiency of this method on acoustic scattering problems.     

Networks for sorting multitonic sequences

Lee and Batcher have designed networks that efficiently merge k separately provided sorted sequences of known lengths totalling n. We show that the design is still possible, and in fact easier to describe, if we do not make use of the lengths, or even the directions of monotonicity, of the individual sequences—the sequences can be provided in a single undelimited concatenation of length n. The depth of the simplest resulting network to sort sequences that are “k-tonic” and of length n is , generalizing Batcher's 1968 results for the extreme values of k (k=2 corresponding to merging, and k=n/2 corresponding to general sorting).The exposition is self-contained and can serve even as an introduction to sorting networks and Batcher's results.