Light Field Image Processing: An Overview Gaochang Wu; Masia, Belen; Jarabo, Adrian ...
IEEE journal of selected topics in signal processing,
10/2017, Volume:
11, Issue:
7
Journal Article
Peer reviewed
Open access
Light field imaging has emerged as a technology allowing to capture richer visual information from our world. As opposed to traditional photography, which captures a 2D projection of the light in the ...scene integrating the angular domain, light fields collect radiance from rays in all directions, demultiplexing the angular information lost in conventional photography. On the one hand, this higher dimensional representation of visual data offers powerful capabilities for scene understanding, and substantially improves the performance of traditional computer vision problems such as depth sensing, post-capture refocusing, segmentation, video stabilization, material classification, etc. On the other hand, the high-dimensionality of light fields also brings up new challenges in terms of data capture, data compression, content editing, and display. Taking these two elements together, research in light field image processing has become increasingly popular in the computer vision, computer graphics, and signal processing communities. In this paper, we present a comprehensive overview and discussion of research in this field over the past 20 years. We focus on all aspects of light field image processing, including basic light field representation and theory, acquisition, super-resolution, depth estimation, compression, editing, processing algorithms for light field display, and computer vision applications of light field data.
Como una de las herramientas más llamativas e intuitivas de predicar el evangelio, el Mapamundi fue presentado en China por los primeros misioneros jesuitas que ingresaron a este país asiático en el ...siglo XVI. El objetivo de introducir el conocimiento geográfico, astronónico y cartográfico de Occidente fue transformar la visión cósmica del pueblo chino, afectando así a sus creencias tradicionales. La indiferencia y resistencia de los literatos chinos ante este acto demuestra que, en efecto, esta operación epistémica trataba de sacudir totalmente la ideología nacional y la estructura social, ambas basadas en la filosofía confuciana. Este artículo tiene como objetivo revelar la tensión fundamental entre el confucianismo y el cristianismo a través de esta irrupción del mapamundi en la época dinásticas.
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•Anaerobic digesters with varied GAC dosages were compared at low and high OLRs.•Methanogenic degradation of acetate was almost unaffected by GAC addition.•GAC dose-dependent ...enhancing effect was found for syntrophic HPr/HBu degradation.•GAC stimulated the enrichment of syntrophic bacteria.
Granular activated carbon (GAC) could promote methane production from organic wastes, but a wide range of dosages has been reported. In present study, different GAC dosages of 0, 0.5, 5 and 25 g/L were supplemented into anaerobic digesters and the methanogenic degradation kinetics of acetate, propionate and butyrate were characterized, respectively. At high organic load of 5 g/L, the degradation rates of propionate and butyrate increased by 1.5–4.7 and 2.5–7.0 times at varied GAC dosages. The methane production rates (Rmax) from propionate and butyrate were significantly elevated when increasing GAC dosage up to 5 g/L. However, only a minor increment was found for acetate degradation either at 1 g/L or 5 g/L. The stimulatory mechanism of GAC for accelerated syntrophic degradation of propionate and butyrate can be primarily attributed to the triggering effect on acetogenesis, as evidenced by the enrichment of syntrophic bacteria e.g. Thermovirga, Synergistaceae, and Syntrophomonas etc.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This letter proposes a new ensemble data-analytics model for PMU-based pre-contingency stability assessment (SA) considering incomplete data measurements. The model consists of a minimum number of ...single classifiers which are, respectively, trained by a strategically selected cluster of PMU measurements. Under any PMU missing scenario, the power grid observability from available PMUs can still be ensured to the maximum extent to maintain the SA accuracy. The proposed method is verified through both theoretical proof and numerical simulations.
Aggregation-caused quenching (ACQ) has long been a problem that inhibits the application of organic light-emitting materials in organic light-emitting diodes, especially near-infrared (NIR) ...materials. Figuring out the reasons that induce ACQ is important for the quantum efficiency enhancement of NIR materials. In this paper, an NIR molecule (TPA-QCN) with thermally activated delayed fluorescence (TADF) is studied based on first-principles calculations and excited-state dynamics investigation in both toluene and in the aggregation state. Our calculation indicates that aggregation can induce a smaller energy gap between the first singlet excited state and the first triplet excited state, which is favorable for TADF. Both the decreased fluorescent rate and the increased nonradiative rate will induce emission quenching in the aggregation state. Based on detailed analyses of the reorganization energy and intermolecular interaction, we find that the hydrogen bond will induce enhanced contribution to the reorganization energy from C–H stretching vibration modes and thus a larger nonradiative rate in the aggregation state than in toluene. A new mechanism of ACQ is proposed, and it could help in the design of new types of NIR-TADF molecules with enhanced fluorescence efficiency.
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IJS, KILJ, NUK, PNG, UL, UM
Pyrazolones are a vital class of heterocycles possessing various biological properties and much attention is paid to the diversified synthesis of enantiopure pyrazolone derivatives. We describe here ...the development of diphenylphosphinoalkanoic acid based chiral bisphosphine ligands, which are successfully applied to the palladium-catalyzed asymmetric allenylation of racemic pyrazol-5-ones. The reaction affords C-allenylation products, optically active pyrazol-5-ones bearing an allene unit, in high chemo- and enantioselectivity, with DACH-ZYC-Phos-C1 as the best ligand. The synthetic potential of the C-allenylation products is demonstrated. Furthermore, the enantioselectivity observed with DACH-ZYC-Phos-C1 is rationalized by density functional theory studies.
Porous chitosan microspheres were successfully developed by the simple procedure of freezing chitosan hydrogel beads and subsequently lyophilizing the frozen structure in present study. The ...characterization of porous chitosan microspheres was subjected to detailed analysis of scanning electron microscopy (SEM), porosity and Fourier transform infrared spectra (FTIR), and their adsorption performance for hexavalent chromium (Cr(VI)) was investigated. Results showed that when the chitosan solution concentration ranged from 2.5% to 3.5% (w/v), porous spherical structures with uniform size distribution and good sphericity formed, and the pore size and porosity could decrease significantly by increasing the concentration of chitosan solution or reducing the freezing temperature. The porous chitosan microsphere prepared with 3% chitosan solution at −40 °C for 200 min experienced the highest Cr(VI) adsorption due to its higher porosity. FTIR result suggested that porous chitosan microspheres provided adsorption sites of the amino and hydroxyl groups for the removal of Cr(VI).
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•Porous chitosan microspheres were successfully prepared by freeze-drying methods.•Pore size and porosity decreased with the increase of chitosan solution concentration.•A lower freezing temperature resulted in smaller pore diameters and tighter network structure.•Microspheres prepared with 3% chitosan solution possessed enhanced Cr(VI) adsorption capacity.•High adsorption capacity was due to morphological structure with large porosity and surface area.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Adenosine-to-inosine (A-to-I) RNA editing leads to a similar effect to A-to-G mutations. RNA editing provides a temporo-spatial flexibility for organisms. Nonsynonymous (Nonsyn) RNA editing in ...insects is over-represented compared with synonymous (Syn) editing, suggesting adaptive signals of positive selection on Nonsyn editing during evolution. We utilized the brain RNA editome of Drosophila melanogaster to systematically study the LD (r2) between editing sites and infer its impact on the adaptive signals of RNA editing. Pairs of editing sites (PESs) were identified from the transcriptome. For CDS PESs of two consecutive editing sites, their occurrence was significantly biased to type-3 PES (Syn-Nonsyn). The haplotype frequency of type-3 PES exhibited a significantly higher abundance of AG than GA, indicating that the rear Nonsyn site is the driver that promotes the editing of the front Syn site (passenger). The exclusion of passenger Syn sites dramatically amplifies the adaptive signal of Nonsyn RNA editing. Our study for the first time quantitatively demonstrates that the linkage between RNA editing events comes from hitchhiking effects and leads to the underestimation of adaptive signals for Nonsyn editing. Our work provides novel insights for studying the evolutionary significance of RNA editing events.
Studying drug-target interactions (DTIs) is the foundational and crucial phase in drug discovery. Biochemical experiments, while being the most reliable method for determining drug-target affinity ...(DTA), are time-consuming and costly, making it challenging to meet the current demands for swift and efficient drug development. Consequently, computational DTA prediction methods have emerged as indispensable tools for this research. In this article, we propose a novel deep learning algorithm named GRA-DTA, for DTA prediction. Specifically, we introduce Bidirectional Gated Recurrent Unit (BiGRU) combined with a soft attention mechanism to learn target representations. We employ Graph Sample and Aggregate (GraphSAGE) to learn drug representation, especially to distinguish the different features of drug and target representations and their dimensional contributions. We merge drug and target representations by an attention neural network (ANN) to learn drug-target pair representations, which are fed into fully connected layers to yield predictive DTA. The experimental results showed that GRA-DTA achieved mean squared error of 0.142 and 0.225 and concordance index reached 0.897 and 0.890 on the benchmark datasets KIBA and Davis, respectively, surpassing the most state-of-the-art DTA prediction algorithms.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
High-level wind power integration can dramatically affect a power system's dynamic performance and introduce significant uncertainties to system's operation. This paper proposes a robust dispatch ...method to optimize the power system's operation state while sustaining its transient stability with highly variable and stochastic wind power generation. The problem is first modeled as an augmented optimal power flow model with uncertain variables and differential-algebraic equations. Then, the stability constraints are converted to approximately-equivalent algebraic equations based on one-machine-infinite-bus equivalence technique and trajectory sensitivity analysis. Next, the uncertain wind power generation is represented by a small number of strategically selected testing scenarios. Finally, a decomposition-based computation strategy is developed to divide the original model into a master problem and a series of slave problems which are solved iteratively. Using industry-grade system dynamic models and simulation software, the proposed method is tested on the New England 39-bus system and Nordic32 system, showing high performance on economic optimality, stability robustness, and computational efficiency.
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