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101.
102.
The purpose of this paper is to show that for continuous functions the related quadratic splines converge without any assumption on the spline grid. The points of the interpolatory grid can be chosen between the corresponding points of the spline grid with a division ratio from \(\frac{{\sqrt 2 }}{2}\) to \(1 - \frac{{\sqrt 2 }}{2}\) . In the case of continuously differentiable functions the division ratio can even be taken between 0 and 1; in addition, the order of convergence is increased. For twice differentiable functions the full order of convergence is obtained. Analogous results about the convergence of histo splines are proved. 相似文献
103.
The absorption, metabolism, and excretion of lanatoside C were studied in hospitalized subjects following oral administration of the tritiated drug. Previous reports of an unusual double peak in plasma levels of radioactivity were confirmed. Fifty plasma samples taken from 31 patients showed that an average of 74% of the radioactive material was digoxin and its metabolites. There was little or no lanatoside C in 36 of the 50 samples of plasma. Similar results were obtained for urine radioactivity. The results confirm that lanatoside C is converted to "digoxin" in the gut prior to absorption as previously proposed by us. "Digoxin" refers to digoxin and its breakdown products, namely, digoxigenin and its mono- and didigitoxosides. According to these proposals, the conversion to "digoxin" takes place partly as a result of acid hydrolysis in the gut and partly by the action of bacteria in the intestine. The effects of concurrent administration of antacid therapy, anticholinergic therapy, and food on the fate of oral lanatoside C were separately studied. There were no significant differences between groups with respect to the amount of radioactive material absorbed or excreted, but there were marked qualitative differences in the plasma profiles. There was a statistically significant increase in the time to the first peak in plasma radioactivity in patients concurrently receiving either food or anticholinergic therapy and there was a significant decrease in the relative height of the first peak in patients treated concurrently with antacid. 相似文献
104.
Thomas H. Alden 《Metallurgical and Materials Transactions A》1977,8(11):1675-1679
According to the theory of thermally-activated deformation, the plastic strain rate equality
will hold in a load relaxation experiment, wheret = 0 is de-fined as the time at which the crosshead stops. In this theory, plastic flow is intrinsically time dependent and
its rate is controlled by interaction of glide dislocations with thermal obstacles(e.g. forest dislocations). The strain rate equation is of the form
and att = 0 none of these variables changes instantaneously. Measurements reported here for [111] aluminum single crystals indicate
that this prediction is wrong. The ratio
is near zero at low stress and approaches unity only at high stress. This result is predicted if plastic strain itself is
time-independent (athermal), as in the author’s recent theory. Time-dependent strain is then the result of thermal changes
in structure, namely loss (recovery) and rearrangement of obstacle dislocations. Experi-ments were also done to test further
the essential hypothesis of Hart’s recent formula-tion of an equation of state for plastic deformation-namely that each distinct
σ-@#@
curve derived from load relaxation data corresponds to a unique “hardness” state and that re-covery does not occur. Significant
differences were observed in the 77 K strsss-strain curves for 295 K relaxed and unrelaxed samples which indicate that substantial
loss and some rearrangement of dislocations has occurred during the relaxation. It is concluded from both experiments that
load relaxation in aluminum is a manifestation of recovery creep and cannot be taken as evidence for a plastic equation of
state. 相似文献
105.
Thomas P. L. Roellig James R. Houck 《Journal of Infrared, Millimeter and Terahertz Waves》1983,4(3):299-309
A new, 1-mm-continuum, bolometer detector system has been constructed employing internal adsorption pumping of He-3 to reach an operating temperature close to 0.4 K. The system spectral bandwidth is 800 to 1200 μm. Although the system was originally designed to be used on the 5-m Hale telescope, it has also been successfully used on the 4-m Anglo-Australian telescope and on the 10-m dish at Owens Valley, California. At the 5-m Hale telescope, the system has a full width-half maximum (FWHM) beam size of 55t" and an instantaneous noise-equivalent flux density of 6 \({{Jy} \mathord{\left/ {\vphantom {{Jy} {\sqrt {Hz} }}} \right. \kern-0em} {\sqrt {Hz} }}\) in good weather. 相似文献
106.
The design of two custom sample holders with a spherical cavity for commercial vibrating sample magnetometer systems is described. For such cavities, the magnetization M[over ->] and the internal magnetic field H(i)[over ->] of a sample are both homogeneous. Consequently, the material parameter M(H(i)) of a sample can be determined even for liquids and powders with a high magnetic susceptibility. 相似文献
107.
108.
109.
Maciej Dabrowski Thomas Acton Hans van der Heijden 《Expert systems with applications》2012,39(9):8279-8287
This paper proposes a novel method for preference relaxation in online product search, which enables consumers to make quality choices without suffering from the commonly experienced information overload. In online shopping scenarios that involve multi-attribute choice tasks, it can be difficult for consumers to process the vast amounts of information available and to make satisfactory buying decisions. In such situations consumers are likely to eliminate potentially good choices early on, using hard-constraint filtering tools. Our approach uses edge sets to identify the alternatives on the soft boundary and the principle of alternative domination to suppress the alternatives on this boundary that are irrelevant. We demonstrate how our approach outperforms existing methods for product search in a set of simulations using two sets of 2650 car advertisements and 1813 digital cameras gathered from a popular online store. 相似文献
110.