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31.
G Chessa Ricotti R Cutrì A De Bernardi M Funis S Frediani 《Canadian Metallurgical Quarterly》1995,17(3):271-273
The authors describe 5 cases, 3 boys and 2 girls, with idiopathic growth hormone deficiency in prepubertal age, treated with human growth hormone. In four of five cases the response to treatment with GH was relevant. Only in one case (F1) the response was negative. The results of this study confirm that rhGH is a safe and effective therapy in children with GHD. 相似文献
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This study, which is based on responses from over 300 individuals in England and Wales, explores how a willingness to use a water-recycling system of specific configuration varies against a number of factors which are linked to system design, system scale, system context, and water-conservation behaviour. Findings show that there is broad willingness to accept in-house water recycling provided that public health is not compromised. 相似文献
35.
Nicholas Biery Marc De Graef Jack Beuth Rafel Raban Andrew Elliott Tresa M. Pollock Curt Austin 《Metallurgical and Materials Transactions A》2002,33(10):3127-3136
Tensile experiments have been performed on specimens of four different investment-cast TiAl-based alloys with variations in
casting conditions. The average ductilities obtained in these experiments vary between approximately 0.8 to 2.0 pct plastic
strain to failure in tension. By using the three-parameter form of the Weibull relation, with the 0.2 pct offset yield strength
as the minimum failure strength, the resulting variability in the data can be quantified and is found to be similar for those
alloys with similar microstructural scale (grain size). Large variations in lamellar volume fraction, segregation, and phase
distribution have a minor influence on property variability, compared to changes in the scale of the grain structure caused
by either variations in cooling rate during casting or the addition of grain refiners. 相似文献
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37.
用迭代法消除数字图像放大后的模糊 总被引:7,自引:3,他引:4
用迭代法对数字图像经过插值放大后产生的模糊问题进行了研究,把数字图像插值放大造成的模糊看成是点扩散函数与清晰图像卷积的结果,根据插值算法可以得到点扩散函数,由于数字图像解卷积是典型的解线性方程组的问题,用雅可比(Jacobi)迭代法得到了很好的结果。与频谱空间变换的方法相比,迭代法没有分母为0的问题和空间变换过程造成的舍入误差。 相似文献
38.
Summary The influence of draw ratio on macroscopic and crystallographic density of polyethylene with different initial morphologies, has been investigated by solid-state extrusion. An initial drop followed by an increase in macroscopic density as a function of draw ratio has been observed. Since precision X-ray measurements of unit cell parameters showed no variation of crystallographic density, it was concluded that plastic deformation of polyethylene upon drawing proceeds with a decrease of the degree of crystallinity. This was confirmed by differential scanning calorimetry. 相似文献
39.
Gregory S. Zaric Jeffrey S. Hoch 《International Transactions in Operational Research》2006,13(6):493-513
Interest in medical savings accounts (MSAs) as a potential tool to reduce healthcare costs has been widespread. A small number of countries have either implemented or run pilot programs of MSAs, and vigorous policy debates have taken place in several other countries about the potential merits of introducing MSAs as a method of paying for health care. In this paper we develop a model to assess the cost saving potential of MSAs in a publicly funded healthcare system. We assume that the public healthcare payer may choose between reimbursing healthcare expenditures through an MSA or through a form of third‐party payer insurance. We use the model to identify the conditions under which MSAs may reduce costs. We illustrate using data on healthcare expenditures from Canada. 相似文献
40.
Olivier Merlin Jeffrey P. Walker Abdelghani Chehbouni Yann Kerr 《Remote sensing of environment》2008,112(10):3935-3946
A deterministic approach for downscaling ~ 40 km resolution Soil Moisture and Ocean Salinity (SMOS) observations is developed from 1 km resolution MODerate resolution Imaging Spectroradiometer (MODIS) data. To account for the lower soil moisture sensitivity of MODIS surface temperature compared to that of L-band brightness temperature, the disaggregation scale is fixed to 10 times the spatial resolution of MODIS thermal data (10 km). Four different analytic downscaling relationships are derived from MODIS and physically-based model predictions of soil evaporative efficiency. The four downscaling algorithms differ with regards to i) the assumed relationship (linear or nonlinear) between soil evaporative efficiency and near-surface soil moisture, and ii) the scale at which soil parameters are available (40 km or 10 km). The 1 km resolution airborne L-band brightness temperature from the National Airborne Field Experiment 2006 (NAFE'06) are used to generate a time series of eleven clear sky 40 km by 60 km near-surface soil moisture observations to represent SMOS pixels across the three-week experiment. The overall root mean square difference between downscaled and observed soil moisture varies between 1.4% v/v and 1.8% v/v depending on the downscaling algorithm used, with soil moisture values ranging from 0 to 15% v/v. The accuracy and robustness of the downscaling algorithms are discussed in terms of their assumptions and applicability to SMOS. 相似文献