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排序方式: 共有560条查询结果,搜索用时 15 毫秒
1.
Chandel Narendra Singh Chakraborty Subir Kumar Rajwade Yogesh Anand Dubey Kumkum Tiwari Mukesh K. Jat Dilip 《Neural computing & applications》2021,33(10):5353-5367
Neural Computing and Applications - The identification of water stress is a major challenge for timely and effective irrigation to ensure global food security and sustainable agriculture. Several... 相似文献
2.
Single-phase voltage source power converters (VSCs) under consideration are AC-DC current-controlled boost-type power converters with bidirectional power-handling capability. Equivalence between two series-connected two-level power converters and a single three-level power converter is considered here. Further considered is the series operation of three-level power converters. Simulation results and experimental verification for both are provided. Economical configurations of three-level power converters leading to multilevel waveforms are presented thereafter 相似文献
3.
A deterministic digital simulation model with finite sum of properly weighted sinusoids is used to simulate a frequency nonselective mobile channel with LOS component. Measurement data are used to optimise the parameters. Which are then used in the deterministic simulation model. The probability distribution and level cross rate (LCR) obtained from the measured data agree well with the analytical and simulation results 相似文献
4.
SI Alexander SB Younes JJ Yunis D Zurakowski N Mirza D Dubey MP Drew WE Harmon EJ Yunis 《Canadian Metallurgical Quarterly》1997,63(12):1756-1761
BACKGROUND: Recipient antidonor cytotoxic T-cell activity has been associated with graft loss and acute rejection in renal allograft recipients. The role of immunologic mechanisms in the development of chronic graft rejection is controversial. We analyzed all living related renal transplants performed at Children's Hospital (Boston, MA) from 1983 to 1995 to assess whether cell-mediated cytotoxicity, determined in vitro and measured before transplantation, was predictive of chronic rejection. METHODS: Eighty-three patients were studied retrospectively. Fifty-seven patients with one haplotype-matched renal transplants from living related donors were studied to determine the association between cell-mediated lympholysis (CML) level, acute rejection, chronic rejection, and graft failure. Acute rejection was defined by the decision to treat. Chronic rejection was defined by histology and/or the absolute serum creatinine value using an increasing serum creatinine level >1.0 mg/dl for children less than 3, a creatinine level >1.5 mg/dl for children between 3 and 10 years of age, and a creatinine level >2.0 mg/dl for children above 10 years of age. Return to dialysis or retransplantation was considered graft failure. RESULTS: Of the 57 haploidentical patients, there were 33 males and 24 females. The mean age at transplant was 11.1 years (SD=6.7). Twelve patients developed chronic rejection, 24 patients developed acute rejection, and 7 patients had graft failure. Pretransplant cytotoxic T lymphocyte activity was associated with chronic rejection (P=0.001) and graft failure (P=0.013) but only marginally with acute rejection (P=0.058). Controlling for age and sex, Cox's proportional hazards model revealed that CML level was predictive of time to chronic rejection (P<0.01) but not acute rejection (P=0.11). It was estimated that every 1-unit increase in CML level raises the monthly risk of chronic rejection by 7%. Ten children received HLA-identical kidneys from their siblings. There were no episodes of chronic rejection after 5 years. Two patients with high CML levels had episodes of acute rejection; both patients responded to treatment. CONCLUSION: Our data demonstrate an association between pretransplant cell-mediated cytotoxicity and the occurrence of chronic rejection in living related one-haploidentical renal transplants in pediatric patients. 相似文献
5.
The temperature dependence of the viscosity of the undercooled melts exhibits an important role in the study of nucleation,
crystal growth and the glass-forming ability of materials. Several attempts have been made to study the viscous behaviour
of the glass-forming melts and these investigations are mainly based on free volume theory as well as on the configurational
entropy model. In the present investigation, an attempt has been made to correlate the thermodynamic parameters with the viscosity
of the glass-forming melts and to study the temperature dependence of the viscosity of undercooled liquids on the basis of
the free volume theory as well as on the basis of the configurational entropy model of Adam and Gibbs. The entire study is
confined on the expression for thermodynamic parameters reported by the authors recently. The expression obtained has been
successfully applied to study the temperature dependence of the viscosity of the metallic, molecular and oxide glass-forming
liquids. 相似文献
6.
Anshu Dubey Klaus Weide Dongwook Lee John Bachan Christopher Daley Samuel Olofin Noel Taylor Paul M. Rich Lynn B. Reid 《Software》2015,45(2):233-244
When developing a complex, multi‐authored code, daily testing on multiple platforms and under a variety of conditions is essential. It is therefore necessary to have a regression test suite that is easily administered and configured, as well as a way to easily view and interpret the test suite results. We describe the methodology for verification of FLASH, a highly capable multiphysics scientific application code with a wide user base. The methodology uses a combination of unit and regression tests and an in‐house testing software that is optimized for operation under limited resources. Although our practical implementations do not always comply with theoretical regression‐testing research, our methodology provides a comprehensive verification of a large scientific code under resource constraints.Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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8.
The flow of ambient air induced solely by buoyancy, through a vertical rod bundle has been modelled as a phenomenon in a porous medium. The rods are at uniform heat flux condition and the circular shell adiabatic. The induced flow rate was found to be controlled by a parameter ψ dependent on the heat flux, rod diameter, length, fluid properties and the bundle permeability. Measurements performed on two 7-rod bundles corroborate the theoretical predictions. Longitudinally averaged heat transfer rates from the central and peripheral rods have also been measured and average information generated for the bundle. 相似文献
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10.
Vinyl carbazole (VC) functionalized ordered mesoporous silica polymer nanocomposites (SBA/VC) were synthesized by in situ radical polymerization of monomers inside the mesoporous framework and characterized for the antibacterial activity studies against gram positive and gram negative bacteria. Powder X-ray diffraction and N2 adsorption isotherms of SBA/VC nanocomposites showed the presence of mesoporous nature. The antimicrobial activity results showed increasing trend with the increase in the concentration of vinyl carbazole (VC) and the maximum antibacterial activity was achieved with SBA/VC64 nanocomposites. 相似文献