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341.
正日前,菲亚特动力科技的高效新款Cursor 16系列柴油机获得《柴油机》杂志评选的2014年度柴油机称号,这是对菲亚特动力科技的新16 L、6缸直列发动机的充分认可。Cursor 16系列发动机尺寸小,输出功率高,具有领先的功率重量比,适用于建筑、农业和发电机领域。与Cursor系列的其他产品相比,16系列柴油机排量最大,拥有优异的可靠性和灵活性。  相似文献   
342.
Abstract

There is growing concern about a crisis in housing affordability in the UK, renewing longstanding debates about what constitutes ‘affordable’ housing. The growing use of the private rented sector by low income households has also led to increased interest in understanding the impact of housing costs on living standards. This paper builds on existing work on ‘residual income’ measures of housing affordability, accepting that what households can afford to pay for housing is related to their ability to cover other costs, and so not directly proportional to income. It proposes a new approach to defining and measuring housing affordability, based on the Minimum Income Standard (MIS). The paper then uses data from the Family Resources Survey (2008/09 to 2015/16) to examine housing affordability within the rented sector across the UK, exploring the value of this measure both in revealing the scale of the ‘problem’ and assessing the likely impact of suggested interventions.  相似文献   
343.
10 white carneaux pigeons trained on an easy wavelength discrimination subsequently performed more accurately on a hard wavelength discrimination than did 10 controls trained on the hard problem from the outset. The effect was not a simple consequence of learning an easy problem, for a 3rd group (N=10), initially trained on the hard wavelength discrimination but with a 2nd relevant dimension added, performed no more accurately than controls. Nor was it due to a greater difference in response strengths to the stimuli of the hard problem, since a 4th group (N=10), initially trained on the reversal of the easy problem, eventually performed more accurately than controls. A 2nd experiment with 20 white carneaux pigeons of the same age, further disconfirmed this 2nd analysis, leaving it probable that the basic result is partly a consequence of the strengthening of attention to the relevant dimension. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
344.
Dubost  G. Rabbaa  A. 《Electronics letters》1985,21(10):426-427
The flat folded dipole has its largest bandwidth when low dielectric substrate is used, and when it acts at both third and fourth resonances. Theory and experiments are in good agreement.  相似文献   
345.
Lydia Lange 《Scientometrics》1985,8(3-4):205-215
The theoretical introductions in empirical journal articles have been analyzed looking for factors determining citation habits. Own-country-biases and English-American predominance in citations were not regularly found. Preferred language of the cited publications and absolute citation frequencies were dependent upon both the disciplines and the countries where the journals are published. However, relative citation frequencies (citations related to the length of the text available) have been found to be rather constant across countries (within psychology and psychiatry, respectively) which indicates no such dependence.  相似文献   
346.
 A fully coupled flow-deformation model is presented for the behaviour of unsaturated porous media. The governing equations are derived based on the equations of equilibrium, effective stress concept, Darcy's law, Henry's law, and the conservation of fluid mass. Macroscopic coupling between the flow and deformation fields is established through the effective stress parameters. The microscopic link between the volumetric deformations of the two pore system (i.e. the pore-air and the pore-water) is established using Betti's reciprocal theorem. Both links are essential for a proper modelling of flow and deformation in unsaturated porous media. The discretised form of the governing equations is obtained using the finite element technique. As application of the model, experimental results from several laboratory tests reported in the literature are modelled numerically. Good agreement is obtained between the numerical and the experimental results in all cases.  相似文献   
347.
White blood cells (WBC) or leukocytes are a vital component of the blood which forms the immune system, which is accountable to fight foreign elements. The WBC images can be exposed to different data analysis approaches which categorize different kinds of WBC. Conventionally, laboratory tests are carried out to determine the kind of WBC which is erroneous and time consuming. Recently, deep learning (DL) models can be employed for automated investigation of WBC images in short duration. Therefore, this paper introduces an Aquila Optimizer with Transfer Learning based Automated White Blood Cells Classification (AOTL-WBCC) technique. The presented AOTL-WBCC model executes data normalization and data augmentation process (rotation and zooming) at the initial stage. In addition, the residual network (ResNet) approach was used for feature extraction in which the initial hyperparameter values of the ResNet model are tuned by the use of AO algorithm. Finally, Bayesian neural network (BNN) classification technique has been implied for the identification of WBC images into distinct classes. The experimental validation of the AOTL-WBCC methodology is performed with the help of Kaggle dataset. The experimental results found that the AOTL-WBCC model has outperformed other techniques which are based on image processing and manual feature engineering approaches under different dimensions.  相似文献   
348.
Carbon Dots (CDs) are luminescent quasi-spherical nanoparticles, possessing water solubility, high biocompatibility, and tunable chemical and physical properties for a wide range of applications, including nanomedicine and theranostics. The evaluation of new purification criteria, useful to achieve more reliable CDs, free from the interference of artifacts, is currently an object of debate in the field. Here, new CDs doped with gadolinium (Gd (III)), named Gd@CNDs, are presented as multifunctional probes for Magnetic Resonance Imaging (MRI). This new system is a case of study, to evaluate and/or combine different purification strategies, as a crucial approach to generate CDs with a better performance. Indeed, these new amorphous Gd@CNDs display good homogeneity, and they are free from emissive side products. Gd@CNDs (7–10 nm) contain 7% of Gd (III) w/w, display suitable and stable longitudinal relaxivity (r1) and with emissive behavior, therefore potentially useful for both MR and fluorescence imaging. They show good biocompatibility in both cellular and in vivo studies, cell permeability, and the ability to generate contrast in cellular pellets. Finally, MRI recording T1-weighted images on mice after intravenous injection of Gd@CNDs, show signal enhancement in the liver, spleen, and kidney 30 min postinjection.  相似文献   
349.
Explicit formulas are presented for the mutual impedance and coupling between two parallel or collinear short-circuited flat dipoles at resonance in terms of three dimensions with respect to wavelength. Experimental and theoretical results are in good agreement and show that the radiating dipoles are particularly well uncoupled and therefore are suitable for incorporation in short arrays for which superdirectivity can be achieved, or in large swept sector arrays.  相似文献   
350.
Tran PD  Batabyal SK  Pramana SS  Barber J  Wong LH  Loo SC 《Nanoscale》2012,4(13):3875-3878
Photocorrosion, that causes rapid deactivation of Cu(2)O photocatalysts, was addressed by incorporating this oxide in a composite with reduced graphene oxide which acts as an electron acceptor to extract photogenerated electrons from Cu(2)O. Cu(2)O-rGO composite engineering also allows enhancing significantly photocatalytic activities of Cu(2)O for H(2) generation.  相似文献   
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