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151.
Michael Burke Ron Cytron Jeanne Ferrante Wilson Hsieh 《The Journal of supercomputing》1989,3(2):71-88
This paper presents an efficient algorithm that automatically generates a parallel program from a dependence-based representation of a sequential program. The resulting parallel program consists of nested fork-join constructs, composed from the loops and statements of the sequential program. Data dependences are handled by two techniques. One technique implicitly satisfies them by sequencing, thereby reducing parallelism. Where increased parallelism results, the other technique eliminates them by privatization: the introduction of process-specific private instances of variables. Additionally, the algorithm determines when copying values of such instances in and out of nested parallel constructs results in greater parallelism. This is the first algorithm for automatically generating parallelism for such a general model. The algorithm generates as much parallelism as is possible in our model while minimizing privatization.An earlier version of this paper was presented at the First Workshop on Languages and Compilers for Vector and Parallel Machines, which was held at Cornell University in August 1988. That same year a select group of these workshop papers were published in two special issues of the journal: volume 2, numbers 2 and 3. 相似文献
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155.
Kilpatrick Dean G.; Ruggiero Kenneth J.; Acierno Ron; Saunders Benjamin E.; Resnick Heidi S.; Best Connie L. 《Canadian Metallurgical Quarterly》2003,71(4):692
With a national household probability sample of 4,023 telephone-interviewed adolescents ages 12-17, this study provides prevalence, comorbidity, and risk-factor data for posttraumatic stress disorder (PTSD), major depressive episode (MDE), and substance abuse/dependence (SA/D). Roughly 16% of boys and 19% of girls met criteria for at least 1 diagnosis. Six-month PTSD prevalence was 3.7% for boys and 6.3% for girls, 6-month MDE prevalence was 7.4% for boys and 13.9% for girls. and 12-month SAM prevalence was 8.2% for boys and 6.2% for girls. PTSD was more likely to be comorbid than were MDE and SA/D. Results generally support the hypothesis that exposure to interpersonal violence (i.e., physical assault, sexual assault, or witnessed violence) increases the risk of these disorders and of diagnostic comorbidity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
156.
Stewart platform configurations (architectures and poses) optimizing local dexterity are investigated. The condition number of the Jacobian matrix is used to quantify the dexterity of the manipulator. For a platform-centered Jacobian reference location and a given characteristic length for scaling purposes, a two-parameter family of optimal configurations is shown to exist. Two suitable architectural parameters defining the family are identified and properties of the optimal configurations are discussed. The optimization results are shown to be easily extended for other Jacobian reference locations and for other singular value-based local dexterity measures. It is suggested that the existence of a two-parameter family of optimal local configurations could be exploited to aid in the resolution of optimal architectures for global measures. 相似文献
157.
The DNA microsatellites can be efficiently used to determine incorrect paternity attribution of cattle without genotyping of dams. Allelic frequencies of the population were determined for 12 microsatellites using the maternal alleles of 102 AI sires. The frequency of the most common microsatellite allele ranged from 0.27 to 0.58. Most loci had at least one allele that was present in only a single individual. Paternity of 9 of 173 cows (5.2%) and 3 of 102 bulls (2.9%) was excluded because putative paternal alleles were not present in progeny for at least one locus. For 4 of the 9 cows and all 3 bulls, exclusion was based on at least two loci. Mean probability of exclusion was 0.85 for cows and 0.99 for bulls. With an assumed cost of US $5 per genotype, a misidentification rate of 5%, and a discount rate of 0.05, additional profit for the Israeli-Holstein breeding program from genotyping 100 test daughters of each young sire becomes positive within 10 yr and reaches nearly US $2.4 million after 20 yr. 相似文献
158.
S Shimonovitz D Patz P Ever-Hadani L Singer D Zacut G Kidroni M Ron 《Canadian Metallurgical Quarterly》1995,23(4):279-282
An exercise for the estimation of the percentage risk of cases of tuberculosis attributable to co-infection HIV/AIDS, using the following formula, is propounded: RA%=p[m2r(hR-h)] + (1-p)[m3r (hR-h)]/p[m1+m2r (hR+1-h)] + (1-p)[m3r (hR+1-h)] x 100 where: p= proportion of BK infected, r= risk of tuberculosis infection, h= proportion of persons infected with HIV, m1= breakdown rate of endogenous tuberculosis, m2= breakdown rate of exogenous tuberculosis, m3= breakdown rate of primary tuberculosis, R= relative risk of morbidity among persons infected with HIV. 相似文献
159.
Harrison Patti L.; Cummings Jack A.; Dawson Margaret; Short Rick J.; Gorin Susan; Palomares Ron 《Canadian Metallurgical Quarterly》2003,18(4):358
The preparations for and the implementation of the 2002 Multisite Conference on the Future of School Psychology are described. The conference goals were to (a) achieve consensus on current and future demands for school psychologists and our profession's ability to meet those demands; (b) conceptualize the practice of school psychology in the face of diminishing numbers and increasing demand for services; and (c) develop an agenda to use the resources we have to maximize the benefits to the children and schools that we serve. A problem-solving model served as the conceptual foundation of the conference. School psychologists at the host site in Indianapolis and 30 remote sites collaborated to identify threats, opportunities, strategies, and action plans to respond better to the needs of children, families and schools. The conference not only generated excitement and hope for our future, but also provided a framework to propel the current and future practice of school psychology. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
160.
Prior research has shown that male black-capped chickadees (Parus atricapillus) raised in the field produce constant relative pitch cues (frequency ratios) in their songs, whereas males reared in isolation from adult song do not. In this study, the authors found that field-reared male chickadees needed fewer than half as many sessions to learn an operant (go/no-go) auditory discrimination that linked S+ note pairs with a constant-frequency ratio than a discrimination that varied the frequency ratio of S+ pairs randomly. Most important, isolation-reared males needed over 5 times as many sessions to learn the constant-ratio discrimination compared with field-reared males. This is, to the authors' knowledge, the first report of impaired pitch discrimination in isolate songbirds. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献