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11.
Allen Karen; Linn Richard T.; Gutierrez Horacio; Willer Barry S. 《Canadian Metallurgical Quarterly》1994,39(1):29
Investigated burden experienced by 60 spouses and 71 parents who served as primary caregivers to individuals with traumatic brain injury (BI). Burden levels, as assessed by the Questionnaire on Resources and Stress (QRS-SF), were compared for spouses and parents. Both parents and spouses exhibited high levels of burden. Relative to spouses, parents reported significantly greater burden related to lifespan care. Spouses reported significantly less personal reward than did parents. The presence of social aggression and cognitive disability in the individual with BI was found to have a greater association with subjective burden of caregivers than was the presence of physical disability or injury severity. Results of previous studies with QRS-SF scores show that the responsibility assumed by spouses and parents of persons with BI was as great as that experienced by families of people with severe chronic physical disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Food products can be high‐pressure processed (HPP) either in bulk or prepackaged in flexible or semi‐rigid packaging materials. In the latter case the packaging material is subjected, together with the food, to high‐pressure treatment. A number of studies have been performed to quantify the effects of high‐pressure processing on the physical and barrier properties of the packaging material, since the integrity of the package during and after processing is of paramount importance to the safety and quality of the food product. This article reviews the results of published research concerning the effect of HPP on packaging materials. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
13.
On the linear and nonlinear complexity profile of nonlinear pseudorandom number generators 总被引:3,自引:0,他引:3
Gutierrez J. Shparlinski I.E. Winterhof A. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2003,49(1):60-64
We obtain lower bounds on the linear and nonlinear complexity profile of a general nonlinear pseudorandom number generator, of the inversive generator, and of a new nonlinear generator called quadratic exponential generator. The results are interesting for applications to cryptography and Monte Carlo methods. 相似文献
14.
We consider the problem of finding a transitive orientation of a comparability graph, such that the edge set of its covering graph contains a given subset of edges. We propose a solution which employs the classical technique of modular tree decomposition. The method leads to a polynomial time algorithm to construct such an orientation or report that it does not exist. 相似文献
15.
M. Sreekanth D. Ruben Sudhakar B.V.S.S.S. Prasad Ajit Kumar Kolar B. Leckner 《Fuel》2008,87(12):2698-2712
A two-dimensional model is developed for the determination of devolatilization time and char yield of cylindrical wood particles in a bubbling fluidized bed combustor. By using the concept of shape factor, the model is extended to particles of cuboid shape. The model prediction of the devolatilization time agrees with the measured data (present and those reported in the literature) for cylindrical and cuboidal shaped particles within ±20% while the char yield is predicted within ±17%. Influence of some important parameters namely, thermal diffusivity, external heat transfer coefficient and shrinkage, on the devolatilization time and char yield are studied. Thermal diffusivity shows noticeable influence on devolatilization time. The external heat transfer coefficient shows little influence beyond a value of 300 W/(m2 K). However particle shrinkage shows negligible effect on the devolatilization time but has a significant influence on the char yield. 相似文献
16.
J. L. Bocos E. Novillo M. M. Petite A. Iza-Mendia I. Gutierrez 《Metallurgical and Materials Transactions A》2003,34(3):827-839
The present work concentrates on the application of orientation imaging microscopy (OIM) based on the electron backscattered
diffraction (EBSD) technique to the investigation of the microstructural evolution of an extra-low carbon (ELC) steel and
a Ti-Nb-bearing interstitial-free (IF) steel, during continuous annealing. Aspects like the nucleation, the evolution of the
recrystallized volume fraction and grain size of grains with different orientations, the interface area limiting recrystallized
{111} regions, and the apparent growth rates have been considered. Different criteria have been applied in order to identify
crystallites produced during annealing. During the first stages of annealing, a network of grain boundaries with misorientations
higher than 10 deg is produced, mainly inside the deformed γ-fiber grains. The crystallites formed within this network, free from cells or subgrains at their interiors, can be considered
as potential nuclei. However, among all, only some of them become effective due to an important selection. The {111} recrystallized
grains have a significant size and number advantage as compared with other texture components, and a hard impingement between
clusters of {111} grains is produced during grain growth. The effect of grain growth behind the recrystallization front seems
to be negligible as compared with the grain coarsening produced by the migration of this front, driven by the cold-work stored
energy. 相似文献
17.
Participating media with an inhomogeneous index of refraction make light follow curved paths. Simulating this in a global
illumination environment has usually been neglected due to the complexity of the calculations involved, sacrificing accurate
physical simulations for efficient visual results.
This paper aims to simulate non-linear media in a more reasonable time than previous works without losing physical correctness.
Accuracy is achieved by solving the Eikonal equation of geometrical optics, which describes the path followed by a light beam
that traverses a non-linear medium. This equation is used in the context of a photon mapping extension. 相似文献
18.
F.J. Rodriguez L.A. García de la Rosa A. Alatorre J. Ibaez L. Godinez S. Gutierrez P. Herrasti 《Progress in Organic Coatings》2007,60(4):297-302
This paper reports the capacity of polypyrrole to reduce toxic hexavalent chromium (Cr(VI)). The influence of using different electrolytes during the polymer's synthesis has been studied. To improve the reduction of Cr(VI), the parameters considered were the polypyrrole morphology and the amount of conducting polymer. Polypyrrole obtained by cyclic voltammetry at a low sweep rate using KBr as supporting electrolyte showed better performance for Cr(VI) reduction compared to coatings obtained by constant potential or cyclic voltammetry at high sweep rates. 相似文献
19.
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
20.
SF Brenière W Morochi MF Bosseno J Ordo?ez T Gutierrez F Vargas N Yaksic F Noireau 《Canadian Metallurgical Quarterly》1998,71(3):269-283
Triatoma sordida is the second species of Triatominae considered of epidemiological significance in Bolivia. Associated with Triatoma infestans in various regions, it is as yet the only triatomine species established in human dwellings in localities of Velasco province, Department of Santa Cruz. This domestication is considered as primary. Flagellate parasites were detected in 16.2% of domiciliary T. sordida and the kDNA-PCR confirmed the presence of Trypanosoma cruzi. Frequencies of T. cruzi clonets 20 and 39, common clonets in Bolivian domestic cycle (T. infestans), were established by their direct detection in feces using PCR and hybridization. These clonets present low frequencies in T. sordida and synanthropic mammals. Forty-six stocks were isolated and analysed by multilocus enzyme electrophoresis (MLEE). The MLEE showed a higher clonal diversity than in T. infestans domestic cycle and the genotypes were clustered in the two principal lineages of T. cruzi. Within each lineage, a broad variability was observed. Mixture of genotypes was mostly observed in mammals. The large diversity of T. cruzi in this cycle should be related to its sylvatic origin. Moreover, the current limited sample of stocks suggests a lineage association with specific hosts. 相似文献