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21.
Jonathan D. Bray Rodolfo B. Sancio Turan Durgunoglu Akin Onalp T. Leslie Youd Jonathan P. Stewart Raymond B. Seed Onder K. Cetin Ertan Bol M. B. Baturay C. Christensen T. Karadayilar 《Canadian Metallurgical Quarterly》2004,130(7):673-685
Ground failure in Adapazari, Turkey during the 1999 Kocaeli earthquake was severe. Hundreds of structures settled, slid, tilted, and collapsed due in part to liquefaction and ground softening. Ground failure was more severe adjacent to and under buildings. The soils that led to severe building damage were generally low plasticity silts. In this paper, the results of a comprehensive investigation of the soils of Adapazari, which included cone penetration test (CPT) profiles followed by borings with standard penetration tests (SPTs) and soil index tests, are presented. The effects of subsurface conditions on the occurrence of ground failure and its resulting effect on building performance are explored through representative case histories. CPT- and SPT-based liquefaction triggering procedures adequately identified soils that liquefied if the clay-size criterion of the Chinese criteria was disregarded. The CPT was able to identify thin seams of loose liquefiable silt, and the SPT (with retrieved samples) allowed for reliable evaluation of the liquefaction susceptibility of fine-grained soils. A well-documented database of in situ and index testing is now available for incorporating in future CPT- and SPT-based liquefaction triggering correlations. 相似文献
22.
Lapsley Daniel K.; Milstead Matt; Quintana Stephen M.; Flannery Daniel; Buss Raymond R. 《Canadian Metallurgical Quarterly》1986,22(6):800
The theoretical relation between adolescent egocentrism and formal operations was addressed in 2 studies. In Study 1, this relation was assessed with the Adolescent Egocentrism Scale (AES; R. Enright et al, see PA, Vols 63:5127 and 65:10218) and a battery of formal reasoning tasks administered to 183 6th-, 8th-, 10th-, and 12th-graders. The results reveal only significant negative or nonsignificant correlations between the measures in early adolescence. There was also no evidence of significant developmental covariation from early to middle adolescence. The validation effort was extended in Study 2 to include 2 measures of adolescent egocentrism (AES and the Imaginary Audience Scale [IAS; D. Elkind and R. Bowen, see PA, Vol 62:5769]) and a 2nd battery of formal operations problems. These measures were administered to 117 7th-, 9th-, and 11th-graders and to 56 undergraduates. There was once again no evidence of significant developmental covariation among the measures. The correlations between the AES and IAS were modest, reflecting differences in the nature and content of the measures. It is concluded that little support exists in this study or in the literature for the crucial theoretical assumption of adolescent egocentrism. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Raymond Devillers 《Acta Informatica》1995,32(4):313-345
The paper shows how to synthesise S-invariants and S-components for Petri Boxes constructed through general recursions, from S-invariants/S-components of their constituents. The construction is based on the tree-structure of the interface places used to define this operator and extends similar results obtained for the refinement operator. Emphasis is put on deriving coverability results; these results are then used to show that all the nets obtained through refinements and recursions from a family covered by S-components are self-concurrency free, at most 2-safe and exhibit a generalised emptiness property; in particular, this is the case for the nets obtained in the translation of the process algebra of Box expressions.Work done within the Esprit Basic Research Working Group 6067 相似文献
24.
This paper discusses the structure and empirical estimation of the County Employment Forecasting System (CEFS), a system used to forecast employment for 32 sectors for each one of the nine counties of the San Francisco Bay Region. CEFS differs in several aspects from the majority of models which attempt to simulate employment change at the subregional level; it explicitly considers the relationships between sectors, it accounts for the interactions between counties, and can provide a set of county forecasts which are consistent with the overall regional projections. 相似文献
25.
The computation of covariance and correlation matrices are critical to many data mining applications and processes. Unfortunately
the classical covariance and correlation matrices are very sensitive to outliers. Robust methods, such as Quadrant Correlation
(QC) and the Maronna method, have been proposed. However, existing algorithms for QC only give acceptable performance when
the dimensionality of the matrix is in the hundreds; and the Maronna method is rarely used in practice because of its high
computational cost. In this paper we develop parallel algorithms for both QC and the Maronna method. We evaluate these parallel
algorithms using a real data set of the gene expression of over 6000 genes, giving rise to a matrix of over 18 million entries.
In our experimental evaluation, we explore scalability in dimensionality and in the number of processors, and the trade-offs
between accuracy and computational efficiency. We also compare the parallel behaviours of the two methods. From a statistical
standpoint, the Maronna method is more robust than QC. From a computational standpoint, while QC requires less computation,
interestingly the Maronna method is much more parallelizable than QC. After a thorough experimentation, we conclude that for
many data mining applications, both QC and Maronna are viable options. Less robust, but faster, QC is the recommended choice
for small parallel platforms. On the other hand, the Maronna method is the recommended choice when a high degree of robustness
is required, or when the parallel platform features a large number of processors (e.g., 32). 相似文献
26.
Michael L. Bates Michael J. Warwick George Shearer David J. Harwood Ira D. Herriman Raymond J. Heitzman David H. Watson 《Journal of the science of food and agriculture》1985,36(1):31-36
The synthetic growth promoter diethylstilboestrol (DES) administered orally to pigs can be detected by radioimmunoassay (RIA) analysis of kidney, liver, faeces, bile and urine from animals fed continuously to slaughter, but not in muscle, fat or plasma. If treated animals are fed on material not containing DES for 72 h prior to slaughter, then the levels of parent compound and metabolite in all products decrease to become not significantly greater than those in control animals. The gross metabolism of DES in pigs and bovines appears to be similar. 相似文献
27.
28.
PG McNally NT Raymond ML Burden PR Burton JL Botha PG Swift AC Burden JR Hearnshaw 《Canadian Metallurgical Quarterly》1995,12(11):961-966
The relative risk of death by calendar date of diagnosis was investigated in a population-based incident cohort of 845 (463 males:382 females) IDDM diagnosed in Leicestershire before the age of 17 years between 1940 and 1989. The mortality status of 844 (99.9%) patients was determined as of the 31 December 1991, representing 14,346 person-years of risk. Trends in relative risk of death were investigated using Cox proportional hazards modelling for within cohort comparisons and age/sex and calendar time adjusted standardized mortality ratios (SMR) using generalized linear modelling for external comparisons. Median age at diagnosis was 10 years (range 3 months to 16 years); median duration of diabetes 15 years (range 1-51 years). Forty-four patients had died (5.2%; median age at death 31 years, range 11-51 years). A further four patients died at presentation (within 24 h) from ketoacidosis and are excluded from all analyses. Calendar date of diagnosis was found to be an important predictor of mortality. Adjusting for attained age there was evidence of a decline in relative risk of death with calendar date of diagnosis of 3.4% (95% CI, 0.005-6.9%) per annum, equivalent to a 32% fall per decade (95% CI, 5-51%), or 84% (95% CI, 21-97) from 1940 to 1989. The data are consistent with a large fall in mortality between the 1940s and 1950s representing over 50% of the total reduction in mortality between 1940 and 1991. Neither sex nor age at diagnosis were significant predictors of mortality. Over the study period 1940-89 the SMR (male and female combined) fell from 981 (541-1556) to 238 (60-953) relative to the general population. This population-based study shows that the prognosis for Type 1 (insulin-dependent) diabetes mellitus has improved markedly over the period 1940-1991. 相似文献
29.
A kinetic analysis of the isothermal nitridation of high-purity oxide-free silicon powder is described. The kinetic analysis suggests that the and polymorphs of Si3N4 are formed by separate and parallel reaction paths. This analysis provides for the decoupling and quantitative kinetic interpretation of- and-Si3N4 formation reactions. Consistent with existing microstructural and thermodynamic evidence, the-forming reaction is shown to obey a first-order rate law, whereas a phase-boundary controlled rate law describes the-forming reaction. A kinetic model employing these rate laws is developed and is used to predict the/ phase ratio as a function of isothermal reaction temperature and extent of reaction. The/ phase ratios so obtained are shown to be in good agreement with experimental observations made under a variety of reaction conditions. 相似文献
30.
Explains changes in the American Psychologist (AP) and reveals plans for 3 special issues in 1992 and 1993 (including a commemorative issue to observe the American Psychological Association's (APA's) centennial year. AP's standard editorial procedure, reasons for some rejections, and reconsideration of submissions are discussed. The editor notes that APA's new building (already a financial success) and its highly successful publications program can become an additional source of income to APA. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献