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991.
Spencer-Rodgers Julie; Williams Melissa J.; Hamilton David L.; Peng Kaiping; Wang Lei 《Canadian Metallurgical Quarterly》2007,93(4):525
In 3 studies, the authors tested the hypothesis that Chinese participants would view social groups as more entitative than would Americans and, as a result, would be more likely to infer personality traits on the basis of group membership--that is, to stereotype. In Study 1, Chinese participants made stronger stereotypic trait inferences than Americans did on the basis of a target's membership in a fictitious group. Studies 2 and 3 showed that Chinese participants perceived diverse groups as more entitative and attributed more internally consistent dispositions to groups and their members. Guided by culturally based lay theories about the entitative nature of groups, Chinese participants may stereotype more readily than do Americans when group membership is available as a source of dispositional inference. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Andrykowski Michael A.; Carpenter Janet S.; Studts Jamie L.; Cordova Matthew J.; Cunningham Lauren L. C.; Beacham Abbie; Sloan David; Kenady Daniel; McGrath Patrick 《Canadian Metallurgical Quarterly》2002,21(5):485
The impact of benign breast biopsy (BBB) on distress and perceptions of risk for breast cancer (BC) was examined. Interviews were conducted with 100 women shortly after notification of biopsy results and 4 and 8 months post-BBB. Compared with matched healthy comparison (HC) women without BBB, the BBB group evidenced greater BC-specific distress at baseline. BC-specific distress declined after BBB, remaining elevated relative to the HC group at the 8-month follow-up. Dispositional (optimism, informational coping style), demographic (education), clinical (family history of BC), and cognitive (BC risk perception) variables were associated with baseline levels of BC-specific distress or persistence of distress. Results support the monitoring process model (S. M. Miller, 1995) and the cognitive social health information processing model (S. M. Miller, Y. Shoda, & K. Hurley, 1996). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Ian Foster David R. Kohr Jr. Rakesh Krishnaiyer Alok Choudhary 《Journal of Parallel and Distributed Computing》1997,45(2):284
Pure data-parallel languages such as High Performance Fortran version 1 (HPF) do not allow efficient expression of mixed task/data-parallel computations or the coupling of separately compiled data-parallel modules. In this paper, we show how these common parallel program structures can be represented, with only minor extensions to the HPF model, by using a coordination library based on the Message Passing Interface (MPI). This library allows data-parallel tasks to exchange distributed data structures using calls to simple communication functions. We present microbenchmark results that characterize the performance of this library and that quantify the impact of optimizations that allow reuse of communication schedules in common situations. In addition, results from two-dimensional FFT, convolution, and multiblock programs demonstrate that the HPF/MPI library can provide performance superior to that of pure HPF. We conclude that this synergistic combination of two parallel programming standards represents a useful approach to task parallelism in a data-parallel framework, increasing the range of problems addressable in HPF without requiring complex compiler technology. 相似文献
994.
Wankang Zhao William Kreahling David Whalley Christopher Healy Frank Mueller 《Real-Time Systems》2006,34(2):129-152
It is advantageous to perform compiler optimizations that attempt to lower the worst-case execution time (WCET) of an embedded application since tasks with lower WCETs are easier to schedule and more likely to meet their deadlines.
Compiler writers in recent years have used profile information to detect the frequently executed paths in a program and there
has been considerable effort to develop compiler optimizations to improve these paths in order to reduce the average-case execution time (ACET). In this paper, we describe an approach to reduce the WCET by adapting and applying optimizations designed for frequent
paths to the worst-case (WC) paths in an application. Instead of profiling to find the frequent paths, our WCET path optimization uses feedback from
a timing analyzer to detect the WC paths in a function. Since these path-based optimizations may increase code size, the subsequent
effects on the WCET due to these optimizations are measured to ensure that the worst-case path optimizations actually improve
the WCET before committing to a code size increase. We evaluate these WC path optimizations and present results showing the
decrease in WCET versus the increase in code size.
A preliminary version of this paper entitled “Improving WCET by optimizing worst-case paths” appeared in the 2005 Real-Time and Embedded Technology and Applications Symposium.
Wankang Zhao received his PhD in Computer Science from Florida State University in 2005. He was an associate professor in Nanjin University
of Post and Telecommunications. He is currently working for Datamaxx Corporation.
William Kreahling received his PhD in Computer Science from Florida State University in 2005. He is currently an assistant professor in the
Math and Computer Science department at Western Carolina University. His research interests include compilers, computer architecture
and parallel computing.
David Whalley received his PhD in CS from the University of Virginia in 1990. He is currently the E.P. Miles professor and chair of the
Computer Science department at Florida State University. His research interests include low-level compiler optimizations,
tools for supporting the development and maintenance of compilers, program performance evaluation tools, predicting execution
time, computer architecture, and embedded systems. Some of the techniques that he developed for new compiler optimizations
and diagnostic tools are currently being applied in industrial and academic compilers. His research is currently supported
by the National Science Foundation. More information about his background and research can be found on his home page, http://www.cs.fsu.edu/∼whalley.
Dr. Whalley is a member of the IEEE Computer Society and the Association for Computing Machinery.
Chris Healy earned a PhD in computer science from Florida State University in 1999, and is currently an associate professor of computer
science at Furman University. His research interests include static and parametric timing analysis, real-time and embedded
systems, compilers and computer architecture. He is committed to research experiences for undergraduate students, and his
work has been supported by funding from the National Science Foundation. He is a member of ACM and the IEEE Computer Society.
Frank Mueller is an Associate Professor in Computer Science and a member of the Centers for Embedded Systems Research (CESR) and High Performance
Simulations (CHiPS) at North Carolina State University. Previously, he held positions at Lawrence Livermore National Laboratory
and Humboldt University Berlin, Germany. He received his Ph.D. from Florida State University in 1994. He has published papers
in the areas of embedded and real-time systems, compilers and parallel and distributed systems. He is a founding member of
the ACM SIGBED board and the steering committee chair of the ACM SIGPLAN LCTES conference. He is a member of the ACM, ACM
SIGPLAN, ACM SIGBED and the IEEE Computer Society. He is a recipient of an NSF Career Award. 相似文献
995.
996.
A computational grid ensures the on-demand delivery of computing resources, in a security-aware, shared, scalable, and standards-based computing environment. A major concern is how to evolve a general and an encompassing framework that guarantees users’ satisfaction measured as Quality of Services (QoS). To obtain a higher QoS, effective QoS perceived by subscribers (users) must conform to specified QoS agreements in the Service Level Agreements (SLAs) document—a legal contract between the Grid Services Provider (GSP) and users. Sometimes the effective user QoS does not conform to the specifications in the SLA because of the vagueness in linguistic definitions in the SLA. Existing approaches overcommitted resources to meet QoS. In this paper, we propose a fuzzy logic framework for calibrating a grid resources user-QoS that addresses the vagueness in linguistic definitions of the SLA document without overcommitting grid resources. 相似文献
997.
L. Lawrence Ho David J. Cavuto Symeon Papavassiliou Anthony G. Zawadzki 《Journal of Network and Systems Management》2001,9(2):139-159
Adaptive algorithms for real-time and proactive detection of network/service anomalies, i.e., soft performance degradations, in transaction-oriented wide area networks (WANs) have been developed. These algorithms (i) adaptively sample and aggregate raw transaction records to compute service-class based traffic intensities, in which potential network anomalies are highlighted; (ii) construct dynamic and service-class based performance thresholds for detecting network and service anomalies; and (iii) perform service-class based and real-time network anomaly detection. These anomaly detection algorithms are implemented as a real-time software system called TRISTAN (
ansaction
n
antaneous
nomaly
otification), which is deployed in the AT&T Transaction Access Services (TAS) network. The TAS network is a commercially important, high volume (millions of transactions per day), multiple service classes (tens), hybrid telecom and data WAN that services transaction traffic such as credit card transactions in the US and neighboring countries. TRISTAN is demonstrated to be capable of automatically and adaptively detecting network/service anomalies and correctly identifying the corresponding "guilty" service classes in TAS. TRISTAN can detect network/service faults that elude detection by the traditional alarm-based network monitoring systems. 相似文献
998.
Bankruptcy prediction has long time been an active research field in finance. One of the main approaches to this issue is
dealing with it as a classification problem. Among the range of instruments available, we focus our attention on the Evolutionary
Nearest Neighbor Classifier (ENPC). In this work we assess the performance of the ENPC comparing it to six alternatives. The
results suggest that this algorithm might be considered a good choice. 相似文献
999.
The main focus of this paper is a pair of new approximation algorithms for certain integer programs. First, for covering integer
programs {min cx:Ax≥b,0≤x≤d} where A has at most k nonzeroes per row, we give a k-approximation algorithm. (We assume A,b,c,d are nonnegative.) For any k≥2 and ε>0, if P≠NP this ratio cannot be improved to k−1−ε, and under the unique games conjecture this ratio cannot be improved to k−ε. One key idea is to replace individual constraints by others that have better rounding properties but the same nonnegative
integral solutions; another critical ingredient is knapsack-cover inequalities. Second, for packing integer programs {max cx:Ax≤b,0≤x≤d} where A has at most k nonzeroes per column, we give a (2k
2+2)-approximation algorithm. Our approach builds on the iterated LP relaxation framework. In addition, we obtain improved
approximations for the second problem when k=2, and for both problems when every A
ij
is small compared to b
i
. Finally, we demonstrate a 17/16-inapproximability for covering integer programs with at most two nonzeroes per column. 相似文献
1000.
半透明物体透明效果的真实感绘制是近年来研究的热点,提出一种针对半透明物体漫散射效果的实时真实感绘制与材质动态编辑方法--基于双向表面散射反射率函数(BSSRDF)的Dipole近似.通过主元分析将Dipole近似中的漫散射材质甬数分解为与形状相关甬数和与半透明材质相关函数的乘积形式;利用该分解表示,在预辐射传输的实时真实感绘制框架下,通过对散射传输的预计算来实现在多种光源环境下对半透明物体材质的实时编辑.此外,还提出一种对预计算辐射传输数据在空域上进行二次小波压缩的方法,利用表面点在空间分布位置的相关性,在保证绘制质量的前提下,大大压缩了数据,提升了绘制效率.实验结果表明,文中方法可以生成具有高度真实感的半透明效果并保证实时的绘制速度. 相似文献