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991.
Bayesian filtering is a general framework for recursively estimating the state of a dynamical system. Key components of each
Bayes filter are probabilistic prediction and observation models. This paper shows how non-parametric Gaussian process (GP)
regression can be used for learning such models from training data. We also show how Gaussian process models can be integrated
into different versions of Bayes filters, namely particle filters and extended and unscented Kalman filters. The resulting
GP-BayesFilters can have several advantages over standard (parametric) filters. Most importantly, GP-BayesFilters do not require
an accurate, parametric model of the system. Given enough training data, they enable improved tracking accuracy compared to
parametric models, and they degrade gracefully with increased model uncertainty. These advantages stem from the fact that
GPs consider both the noise in the system and the uncertainty in the model. If an approximate parametric model is available,
it can be incorporated into the GP, resulting in further performance improvements. In experiments, we show different properties
of GP-BayesFilters using data collected with an autonomous micro-blimp as well as synthetic data.
相似文献
Dieter FoxEmail: |
992.
Position‐Sensitive Array Photodetector Based on Comb‐Like CdS Nanostructure with Cone‐Shape Branches
Yan Hao Shuai Guo Dieter Weller Min Zhang Chunjie Ding Ke Chai Lingling Xie Ruibin Liu 《Advanced functional materials》2019,29(1)
2D microscale position‐sensitive detectors (PSDs) are highly desirable with the degree of integration increase and the size reduction of nanodevices, which are still unavailable. Multichannel devices with outstanding photoelectric properties attract considerable interest as powerful building blocks to be applied in on‐chip systems. Here, based on a highly ordered comb‐like CdS nanowire array with cone‐shape branches through a one‐step synthesis strategy, a high‐resolution 2D position‐sensitive photodetector is realized through variable resistance in different transportation routes and variable optical responses at different parts of the cone‐shape branches, which enable accurate position identification of incident light in various zones of nanowire arrays according to photocurrent changes. In a broadband from 310 to 560 nm, the PSD exhibits high sensitivity with 85 and 58 KΩ µm?1 in the trunk and branch part, respectively, and an ultrafast optical response shorter than tens of millisecond. Moreover, a lower conductivity change rate per unit temperature of the PSD (1.625 × 10?9 A V?1 K?1) than that of commercial Si‐based PSDs (≈6.67 × 10?7 A V?1 K?1) reveals outstanding low‐temperature performance. Finally, the multichannel nanostructure based PSD with nanoscale resolution is applied to high‐accuracy quadrant photodetectors. 相似文献
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Shanshan Zhang Seyed M. Hosseini Ren Gunder Andrei Petsiuk Pietro Caprioglio Christian M. Wolff Safa Shoaee Paul Meredith Susan Schorr Thomas Unold Paul L. Burn Dieter Neher Martin Stolterfoht 《Advanced materials (Deerfield Beach, Fla.)》2019,31(30)
2D Ruddlesden–Popper perovskite (RPP) solar cells have excellent environmental stability. However, the power conversion efficiency (PCE) of RPP cells remains inferior to 3D perovskite‐based cells. Herein, 2D (CH3(CH2)3NH3)2(CH3NH3)n?1PbnI3n+1 perovskite cells with different numbers of [PbI6]4? sheets (n = 2–4) are analyzed. Photoluminescence quantum yield (PLQY) measurements show that nonradiative open‐circuit voltage (VOC) losses outweigh radiative losses in materials with n > 2. The n = 3 and n = 4 films exhibit a higher PLQY than the standard 3D methylammonium lead iodide perovskite although this is accompanied by increased interfacial recombination at the top perovskite/C60 interface. This tradeoff results in a similar PLQY in all devices, including the n = 2 system where the perovskite bulk dominates the recombination properties of the cell. In most cases the quasi‐Fermi level splitting matches the device VOC within 20 meV, which indicates minimal recombination losses at the metal contacts. The results show that poor charge transport rather than exciton dissociation is the primary reason for the reduction in fill factor of the RPP devices. Optimized n = 4 RPP solar cells had PCEs of 13% with significant potential for further improvements. 相似文献
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Jürgen Nagel Doreen Scheidler Bernd Hupfer Matthias Bruer Dieter Pleul Claus Vogel Dieter Lehmann Simon Amesder 《应用聚合物科学杂志》2006,100(4):2992-2999
Blends of different types of polypropylenes (PP) with polyamide 6 (PA6) were produced by extrusion. The PPs used were a PP homopolymer, a maleic anhydride‐grafted homopolymer, and an acrylic acid‐grafted homopolymer. The blends were characterized by DSC measurements, selective extraction, infrared spectroscopy, REM microscopy, melt rheology, and their mechanical properties. Three types of interactions in the blends as well as in two‐component composites mold by the core‐back process could be identified. Blends of PP with PA6 were not compatible, and two‐component bars could not be produced. Blends of PPgAA and PA6 were made compatible during reactive extrusion. Two‐component bars could be produced only with a blend containing 50 wt % PA6. The composite formation was based on the interdiffusion of PA6 in both components and the reactive compatibilization in the blends. Blends of PPgMAn were also compatibilized during reactive extrusion. The composite formation on two‐component injection molding was based on two mechanisms: the interdiffusion at sites, where PA6 chains of both the components came into contact, and an interfacial reaction, where PPgMAn and PA6 came into contact. The interfacial reaction was supported by the high mobility of the first component at the temperature of the melt of the second component. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2992–2999, 2006 相似文献
998.
Local repair procedure for carbon‐fiber‐reinforced plastics by refilling with a thermoset matrix
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Kristin Küchler Elias Staiger Rolf‐Dieter Hund Olaf Diestel Martin Kirsten Chokri Cherif 《应用聚合物科学杂志》2016,133(6)
Textile‐reinforced composites have given rise to an increasingly important key technology for lightweight construction in aerospace, automotive, civil engineering, and many other industries. Because there exists no suitable repair procedure for carbon‐fiber‐reinforced plastics (CFRPs), damaged parts have to be replaced completely; this is extremely disadvantageous both ecologically and economically. With fiber‐reinforced composites used being more and more often, fast and efficient methods for the local repair of damaged CFRPs are essential. In this article, a novel repair procedure for CFRP is presented. The thermal activation by IR radiation of oxide semiconductors was used to locally degrade the thermoset matrix of the damaged CFRP through the maintenance of its structural stability and properties. The matrix‐free textile structure was then refilled with a thermoset epoxy matrix. Carbon fibers from the treated area were characterized with scanning electron microscopy, IR spectroscopy, thermogravimetric analysis, and subsequently, tensile strength for single fibers to verify the effectiveness of the procedure. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42964. 相似文献
999.
Mannose‐Decorated Multicomponent Supramolecular Polymers Trigger Effective Uptake into Antigen‐Presenting Cells
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David Straßburger Natascha Stergiou Moritz Urschbach Dr. Hajime Yurugi Daniel Spitzer Dr. Dieter Schollmeyer Prof. Dr. Edgar Schmitt Prof. Dr. Pol Besenius 《Chembiochem : a European journal of chemical biology》2018,19(9):912-916
A modular route to prepare functional self‐assembling dendritic peptide amphiphiles decorated with mannosides, to effectively target antigen‐presenting cells, such as macrophages, is reported. The monomeric building blocks were equipped with tetra(ethylene glycol)s (TEGs) or labeled with a Cy3 fluorescent probe. Experiments on the uptake of the multifunctional supramolecular particles into murine macrophages (Mφs) were monitored by confocal microscopy and fluorescence‐activated cell sorting. Mannose‐decorated supramolecular polymers trigger a significantly higher cellular uptake and distribution, relative to TEG carrying bare polymers. No cytotoxicity or negative impact on cytokine production of the treated Mφs was observed, which emphasized their biocompatibility. The modular nature of the multicomponent supramolecular polymer coassembly protocol is a promising platform to develop fully synthetic multifunctional vaccines, for example, in cancer immunotherapy. 相似文献
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