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991.
Victor F. Rodriguez-Galiano Eulogio Pardo-Igúzquiza Mario Chica-Olmo Javier Mateos Juan P. Rigol-Sánchez Miguel Vega 《International journal of remote sensing》2013,34(20):6574-6599
This article compares a set of relevant methods, based on different mathematical approaches, for Landsat 7 Enhanced Thematic Mapper Plus (ETM+) pansharpening. These are classical procedures such as principal component analysis and fast intensity hue saturation; methods based on wavelet transforms, such as wavelet à trous, additive wavelet luminance proportional and multidirectional–multiresolution methods; a method of a geostatistical nature, called downscaling cokriging (DCK); and finally, a Bayesian method (1cor). The comparison of the fused images is based on the qualitative and quantitative evaluation of their spatial and spectral characteristics by calculating statistical indices and parameters that measure the quality and coherence of the images. Moreover, the quality of the spectral information is studied indirectly by means of the Iterative Self-Organizing Data Analysis Technique (ISODATA) classification of the products of fusion. The results show that DCK and 1cor methods yielded better results than the wavelet-based methods. Particularly, DCK does not introduce artefacts in the estimation of the digital numbers corresponding with the source multispectral image and, therefore, it can be considered as the most coherent method. 相似文献
992.
Thiago Pereira Emilio Vital Brazil Ives Macêdo Mario Costa Sousa Luiz Henrique de Figueiredo Luiz Velho 《Graphical Models》2011,73(4):97-110
While current image deformation methods are careful in making the new geometry seem right, little attention has been given to the photometric aspects. We introduce a deformation method that results in coherently illuminated objects. For this task, we use RGBN images to support a relighting step integrated in a sketch-based deformation method. We warp not only colors but also normals. Normal warping requires smooth warping fields. We use sketches to specify sparse warping samples and impose additional constraints for region of interest control. To satisfy these new constraints, we present a novel image warping method based on Hermite–Birkhoff interpolation with radial basis functions that results in a smooth warping field. We also use sketches to help the system identify both lighting conditions and material from single images. We present results with RGBN images from different sources, including photometric stereo, synthetic images, and photographs. 相似文献
993.
Dario Conte Mario Marcello Miglietta Agata Moscatello Steve Albers Vincenzo Levizzani 《Environmental Modelling & Software》2010,25(10):1064-1074
The Local Analysis and Prediction System (LAPS) is modified to ingest Meteosat Second Generation (MSG) data for cloud analysis. A first study is conducted to test the actual performance of the weather analysis software after new satellite bands are introduced. Results show that the system provides high quality cloud products such as cloud mask, cloud top height and cloudiness. A comparison with products from EUMETSAT’s Nowcasting SAF shows a general underestimation of the LAPS product although the results are not conclusive. The study shows the potential of MSG data in refining the mesoscale analyses produced by LAPS. Moreover the software tools, based on open source codes for geolocation and geographical information systems, written for the transformation of MSG data into input files for LAPS have demonstrated a great flexibility and ease of use. The study opens up an avenue for successive validation and refinement of the analyses together with their improved implementation for operational nowcasting and very short range forecasting applications. 相似文献
994.
This paper reviews and compares different special transfer functions, of nonminimum order, characterized by low poleQ's and high selectivity. These functions extend the use of the cascade configuration, employing standard low-order sections implemented by active devices, to selective filters.Part of this work has been presented at the 5th European Conference on Circuit Theory and Design, The Hague, The Netherlands, August 25–28, 1981. 相似文献
995.
The high -field nonlinear NMR absorption signal of the B phase of 3He with an arbitrary orientation of the rotation axis n with respect to the field is calculated to third order in the amplitude of the perpendicular magnetization. An instability like those in ferromagnetic resonances is predicted, which changes its asymmetry with respect to the sense of sweeping at an orientation angle of 35 .On leave of absence from the Technical University of Munich. Postdoctoral Research Fellow of the DFG (German Science Foundation). 相似文献
996.
Silvia Cascianelli Gabriele Costante Francesco Crocetti Elisa Ricci Paolo Valigi Mario Luca Fravolini 《Asian journal of control》2021,23(1):57-71
In this paper, a data‐based approach for the design of structured residual subsets for the robust isolation of sensor faults is proposed. Linear regression models are employed to estimate faulty signals and to build a set of primary residuals. L1‐regularized least squares estimation is used to identify model parameters and to enforce sparsity of the solutions by increasing the regularization weight. In this way, it is possible to generate a set of residuals generators with different fault sensitivity. Then, a residual selection procedure based on fault sensitivity maximization is proposed to extract a minimum size subset of structured residuals that allows for isolation of the faulty sensor. To overcome modelling uncertainty, a robust recursive Bayesian Filter has been employed to process, online, the distance of the residuals from nominal fault directions, providing a fault probability for each sensor. The proposed method has been validated by designing and testing a fault isolation scheme for six aircraft sensors using multi‐flight experimental data of a P92 Tecnam aircraft. 相似文献
997.
Tomás Martínez-Ruiz Jürgen Münch Félix García Mario Piattini 《Software Quality Journal》2012,20(1):229-260
Organizations developing software-based systems or services often need to tailor process reference models—including product-oriented
and project-oriented processes—to meet both their own characteristics and those of their projects. Existing process reference
models, however, are often defined in a generic manner. They typically offer only limited mechanisms for adapting processes
to the needs of organizational units, project goals, and project environments. This article presents a systematic literature
review of peer-reviewed conference and journal articles published between 1990 and 2009. Our aim was both to identify requirements
for process-tailoring notation and to analyze those tailoring mechanisms that are currently in existence and that consistently
support process tailoring. The results show that the software engineering community has demonstrated an ever-increasing interest
in software process tailoring, ranging from the consideration of theoretical proposals regarding how to tailor processes to
the scrutiny of practical experiences in organizations. Existing tailoring mechanisms principally permit the modeling of variations
of activities, artifacts, or roles by insertion or deletion. Two types of variations have been proposed: the individual modification
of process elements and the simultaneous variation of several process elements. Resolving tailoring primarily refers to selecting
or deselecting optional elements or to choosing between alternatives. It is sometimes guided by explicitly defined processes
and supported by tools or mechanisms from the field of knowledge engineering. The study results show that tailoring notations
are not as mature as the industry requires if they are to provide the kind of support for process tailoring that fulfills
the requirements identified, i.e., including security policies for the whole process, or carrying out one activity rather
than another. A notation must therefore be built, which takes these requirements into consideration in order to permit variant-rich
processes representation and use this variability to consistently support process tailoring. 相似文献
998.
999.
Shruthi Thada Gabor L. Horvath Mario M. Müller Nickel Dittrich Melanie L. Conrad Saubashya Sur Abid Hussain Karin Pelka Suman Latha Gaddam Eicke Latz Hortense Slevogt Ralf R. Schumann Sanne Burkert 《International journal of molecular sciences》2021,22(4)
The interaction and crosstalk of Toll-like receptors (TLRs) is an established pathway in which the innate immune system recognises and fights pathogens. In a single nucleotide polymorphisms (SNP) analysis of an Indian cohort, we found evidence for both TLR4-399T and TRL8-1A conveying increased susceptibility towards tuberculosis (TB) in an interdependent manner, even though there is no established TLR4 ligand present in Mycobacterium tuberculosis (Mtb), which is the causative pathogen of TB. Docking studies revealed that TLR4 and TLR8 can build a heterodimer, allowing interaction with TLR8 ligands. The conformational change of TLR4-399T might impair this interaction. With immunoprecipitation and mass spectrometry, we precipitated TLR4 with TLR8-targeted antibodies, indicating heterodimerisation. Confocal microscopy confirmed a high co-localisation frequency of TLR4 and TLR8 that further increased upon TLR8 stimulation. The heterodimerisation of TLR4 and TLR8 led to an induction of IL12p40, NF-κB, and IRF3. TLR4-399T in interaction with TLR8 induced an increased NF-κB response as compared to TLR4-399C, which was potentially caused by an alteration of subsequent immunological pathways involving type I IFNs. In summary, we present evidence that the heterodimerisation of TLR4 and TLR8 at the endosome is involved in Mtb recognition via TLR8 ligands, such as microbial RNA, which induces a Th1 response. These findings may lead to novel targets for therapeutic interventions and vaccine development regarding TB. 相似文献
1000.
The paper presents a brief history of ring rolling development at the Dresden University of Technology (DUT) from the 70s to the present. The technological scope covers the techniques explored at the DUT: Tangential profile ring rolling, axial profile tube rolling/roll plunging and the TRENPRO® method to produce shaped rings. Starting from the state of the art, technological principle, range of application and machine‐oriented implementation of these techniques are described. Furthermore, other common ring rolling variants, such as axial profile ring rolling, skew‐rolling and radial‐axial ring rolling, are taken into consideration. Finally, the authors provide a summary of problems still to be solved and ways to refine and disseminate the “ring rolling” discipline, assessing the rolling methods’ potential as extremely forward‐looking. 相似文献