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101.
Validation of Ozone Monitoring Instrument UV Satellite Data Using Spectral and Broadband Surface Based Measurements at a Queensland Site 下载免费PDF全文
Mustapha A. A Jebar Alfio V. Parisi Nathan J. Downs Joanna F. Turner 《Photochemistry and photobiology》2017,93(5):1289-1293
This research reconstructed and validated the broadband UVA irradiances derived from discrete spectral irradiance data retrieved from the Ozone Monitoring Instrument (OMI) satellite from 1 January to 31 December 2009. OMI data at solar noon were compared to ground‐based spectral irradiances at Toowoomba (27°36′ S 151°55′ E), Australia, at 310, 324 and 380 nm for both cloud‐free and all sky conditions. There was a strong relationship between the ground‐based UV spectroradiometer data and satellite‐based measurements with an R2 of 0.89 or better in each waveband for cloud‐free days. The data show an overestimate of the satellite‐derived spectral irradiances compared to the ground‐based data. The models developed for the subtropical site data account for this overestimation and are essential for any data correlation between satellite‐ and ground‐based measurements. Additionally, this research has compared solar noon broadband UVA irradiances evaluated with a model and the discrete satellite spectral irradiances for the solar noon values of cloud‐free days to those measured with a ground‐based UVA radiometer. An R2 of 0.86 was obtained confirming that for cloud‐free days the broadband UVA can be evaluated from the OMI satellite spectral irradiances. 相似文献
102.
Minimizing exposure to ultraviolet (UV) radiation is an essential component of skin cancer prevention. Providing and using natural and built shade is an effective protection measure against harmful UV. This article describes the factors that must be addressed to ensure quality, effective, well‐designed shade and recommends best practice approaches to improving the protection factor (PF) of shade structures. It identifies examples of interventions to increase shade availability and use, and examples of effective shade based on measured protection factors or measured reductions in UV exposures. Finally, this article considers examples of best practice for undertaking shade audits. The article is based on refereed articles and reviews, reports, conference papers and shade practice and policies from reports and on web sites. Articles for the Australian setting are considered first, followed by those in an international setting. 相似文献
103.
Alfio Borzì Georg Propst 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2003,4(2):1050-1072
The Liebau phenomenon is the occurrence of valveless
pumping through the application of a periodic force at a place
which lies asymmetric with respect to system configuration. This
paper is concerned with two different physical configurations and
respective models. Comparison and derivation among the models is
discussed. Accurate numerical schemes which solve these models are
presented. By means of numerical simulations it is investigated
under which conditions valveless pumping takes place. 相似文献
104.
Alain Merschaert Pascal Boquel Hugo Gorissen Jean-Pierre Van Hoeck Alfio Borghese Luc Antoine Vincent Mancuso Anne Mockel Michel Vanmarsenille 《Tetrahedron letters》2006,47(47):8285-8288
We have developed a new synthesis of 3,4-disubstituted-1,2,5-thiadiazoles. The methodology is based on the ring opening of readily available 3,4-dichloro-1,2,5-thiadiazole with metal amides to afford a stable synthon, which is then transformed into the 3,4-disubstituted-1,2,5-thiadiazole derivatives via two consecutive reactions with O-, S-, N- or C-nucleophiles. 相似文献
105.
Efficient evaluation of the material response of tissues reinforced by statistically oriented fibres
Kotaybah Hashlamoun Alfio Grillo Salvatore Federico 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2016,67(5):113
For several classes of soft biological tissues, modelling complexity is in part due to the arrangement of the collagen fibres. In general, the arrangement of the fibres can be described by defining, at each point in the tissue, the structure tensor (i.e. the tensor product of the unit vector of the local fibre arrangement by itself) and a probability distribution of orientation. In this approach, assuming that the fibres do not interact with each other, the overall contribution of the collagen fibres to a given mechanical property of the tissue can be estimated by means of an averaging integral of the constitutive function describing the mechanical property at study over the set of all possible directions in space. Except for the particular case of fibre constitutive functions that are polynomial in the transversely isotropic invariants of the deformation, the averaging integral cannot be evaluated directly, in a single calculation because, in general, the integrand depends both on deformation and on fibre orientation in a non-separable way. The problem is thus, in a sense, analogous to that of solving the integral of a function of two variables, which cannot be split up into the product of two functions, each depending only on one of the variables. Although numerical schemes can be used to evaluate the integral at each deformation increment, this is computationally expensive. With the purpose of containing computational costs, this work proposes approximation methods that are based on the direct integrability of polynomial functions and that do not require the step-by-step evaluation of the averaging integrals. Three different methods are proposed: (a) a Taylor expansion of the fibre constitutive function in the transversely isotropic invariants of the deformation; (b) a Taylor expansion of the fibre constitutive function in the structure tensor; (c) for the case of a fibre constitutive function having a polynomial argument, an approximation in which the directional average of the constitutive function is replaced by the constitutive function evaluated at the directional average of the argument. Each of the proposed methods approximates the averaged constitutive function in such a way that it is multiplicatively decomposed into the product of a function of the deformation only and a function of the structure tensors only. In order to assess the accuracy of these methods, we evaluate the constitutive functions of the elastic potential and the Cauchy stress, for a biaxial test, under different conditions, i.e. different fibre distributions and different ratios of the nominal strains in the two directions. The results are then compared against those obtained for an averaging method available in the literature, as well as against the integration made at each increment of deformation. 相似文献
106.
Alfio Torrisi Luciano Velardi Antonio Serra Daniela Manno Lorenzo Torrisi Lucio Calcagnile 《Surface and interface analysis : SIA》2022,54(5):567-575
The properties of graphene oxide foils were modified by excimer laser irradiation at different fluences and times. The irradiations were performed in air and in vacuum using a pulsed UV laser operating at 248-nm wavelength and 23-ns pulse duration. Measurements of ablation yield, microscope surface morphology and Raman spectroscopy were performed. The residual surface shows a significant oxygen reduction due to the removing of functional oxygen groups, a thickness reduction due to the removal of graphene layers depending on the used laser shots and a presence of defects in the graphene sheets as evident by the Raman spectroscopy investigation. 相似文献
107.
In this article the Stokes equations are considered in a domain simulating a capillary bed system. The capillaries are supposed to be thin, parallel and periodic. An asymptotic approximation is constructed. The macroscopic pressure satisfies a Robin interface condition whose coefficients are calculated numerically through a finite element approximation of a boundary layer problem, which is inspired to a domain decomposition technique. 相似文献
108.
We study all the possible Hilbert functions of 0-dimensional subschemes of irreducible curves of a smooth quadric of ?3. We obtain characterizations in case of complete intersection, arithmetically Cohen-Macaulay and arithmetically Buchsbaum curves and other necessary conditions in the general cases. 相似文献
109.
In this paper we present a compact review on the mostly used techniques for computational reduction in numerical approximation of partial differential equations. We highlight the common features of these techniques and provide a detailed presentation of the reduced basis method, focusing on greedy algorithms for the construction of the reduced spaces. An alternative family of reduction techniques based on surrogate response surface models is briefly recalled too. Then, a simple example dealing with inviscid flows is presented, showing the reliability of the reduced basis method and a comparison between this technique and some surrogate models. 相似文献
110.
Acoustic Analysis of Voice Quality with or without False Vocal Fold Displacement After Cordectomy 总被引:2,自引:0,他引:2
Conventional cordectomy by means of a laryngofissure is one of the therapeutic options for treatment of early glottic cancer. To improve the poor voice quality related to this kind of operation, many authors have developed different techniques to repair the mucosal defect. We analyzed voice quality acoustically and compared it after cordectomy alone and after cordectomy with the reconstruction of the vocal cord in a group of 14 patients affected by T1 glottic carcinoma. All the patients underwent postoperative speech therapy. Three patients who underwent cordectomy with reconstruction showed the presence of diplophonia, while two patients without reconstruction showed the presence of bitonality. The differences of the acoustic parameters (jitter, shimmer, harmonic-to-noise ratio) between the two groups of patients were not statistically significant. Reconstruction of the vocal cord does not seem to improve voice quality after cordectomy even in combination with postoperative speech therapy. 相似文献