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991.
Generating automatically labeled data for author name disambiguation: an iterative clustering method
Scientometrics - To train algorithms for supervised author name disambiguation, many studies have relied on hand-labeled truth data that are very laborious to generate. This paper shows that... 相似文献
992.
Yang Song Usha Kadiyala Priyan Weerappuli Jordan J. Valdez Srilakshmi Yalavarthi Cameron Louttit Jason S. Knight James J. Moon David S. Weiss J. Scott VanEpps Shuichi Takayama 《Advanced materials (Deerfield Beach, Fla.)》2019,31(14)
Neutrophil extracellular traps (NETs) are decondensed chromatin networks released by neutrophils that can trap and kill pathogens but can also paradoxically promote biofilms. The mechanism of NET functions remains ambiguous, at least in part, due to their complex and variable compositions. To unravel the antimicrobial performance of NETs, a minimalistic NET‐like synthetic structure, termed “microwebs,” is produced by the sonochemical complexation of DNA and histone. The prepared microwebs have structural similarity to NETs at the nanometer to micrometer dimensions but with well‐defined molecular compositions. Microwebs prepared with different DNA to histone ratios show that microwebs trap pathogenic Escherichia coli in a manner similar to NETs when the zeta potential of the microwebs is positive. The DNA nanofiber networks and the bactericidal histone constituting the microwebs inhibit the growth of E. coli. Moreover, microwebs work synergistically with colistin sulfate, a common and a last‐resort antibiotic, by targeting the cell envelope of pathogenic bacteria. The synthesis of microwebs enables mechanistic studies not possible with NETs, and it opens new possibilities for constructing biomimetic bacterial microenvironments to better understand and predict physiological pathogen responses. 相似文献
993.
Multimedia Tools and Applications - Most video-based detection systems rely on extracting visual features directly from divided original frames or detected motion regions achieved using... 相似文献
994.
Joe Hangil Kim Jason Yu Son-Cheol 《International Journal of Control, Automation and Systems》2020,18(3):587-596
International Journal of Control, Automation and Systems - We propose a sequential method to extract 3-dimensional information for mapping by using sensor fusion of two sonar devices. The 3D... 相似文献
995.
Yijun Shen Joseph Henry He Wang Edmond S. L. Ho Taku Komura Hubert P. H. Shum 《Computer Graphics Forum》2018,37(6):382-394
Controlling a crowd using multi‐touch devices appeals to the computer games and animation industries, as such devices provide a high‐dimensional control signal that can effectively define the crowd formation and movement. However, existing works relying on pre‐defined control schemes require the users to learn a scheme that may not be intuitive. We propose a data‐driven gesture‐based crowd control system, in which the control scheme is learned from example gestures provided by different users. In particular, we build a database with pairwise samples of gestures and crowd motions. To effectively generalize the gesture style of different users, such as the use of different numbers of fingers, we propose a set of gesture features for representing a set of hand gesture trajectories. Similarly, to represent crowd motion trajectories of different numbers of characters over time, we propose a set of crowd motion features that are extracted from a Gaussian mixture model. Given a run‐time gesture, our system extracts the K nearest gestures from the database and interpolates the corresponding crowd motions in order to generate the run‐time control. Our system is accurate and efficient, making it suitable for real‐time applications such as real‐time strategy games and interactive animation controls. 相似文献
996.
This work focuses on simultaneous approximation terms (SATs) for multidimensional summation-by-parts (SBP) discretizations of linear second-order partial differential equations with variable coefficients. Through the analysis of adjoint consistency and stability, we present several conditions on the SAT penalties for general operators, including those operators that do not have nodes on their boundary or do not correspond with a collocation discontinuous Galerkin method. Based on these conditions, we generalize the modified scheme of Bassi and Rebay and the symmetric interior penalty Galerkin method to SBP-SAT discretizations. Numerical experiments are carried out on unstructured grids with triangular elements to verify the theoretical results. 相似文献
997.
Lucas Friedrich David C. Del Rey Fernández Andrew R. Winters Gregor J. Gassner David W. Zingg Jason Hicken 《Journal of scientific computing》2018,75(2):657-686
Non-conforming numerical approximations offer increased flexibility for applications that require high resolution in a localized area of the computational domain or near complex geometries. Two key properties for non-conforming methods to be applicable to real world applications are conservation and energy stability. The summation-by-parts (SBP) property, which certain finite-difference and discontinuous Galerkin methods have, finds success for the numerical approximation of hyperbolic conservation laws, because the proofs of energy stability and conservation can discretely mimic the continuous analysis of partial differential equations. In addition, SBP methods can be developed with high-order accuracy, which is useful for simulations that contain multiple spatial and temporal scales. However, existing non-conforming SBP schemes result in a reduction of the overall degree of the scheme, which leads to a reduction in the order of the solution error. This loss of degree is due to the particular interface coupling through a simultaneous-approximation-term (SAT). We present in this work a novel class of SBP–SAT operators that maintain conservation, energy stability, and have no loss of the degree of the scheme for non-conforming approximations. The new degree preserving discretizations require an ansatz that the norm matrix of the SBP operator is of a degree \(\ge 2p\), in contrast to, for example, existing finite difference SBP operators, where the norm matrix is \(2p-1\) accurate. We demonstrate the fundamental properties of the new scheme with rigorous mathematical analysis as well as numerical verification. 相似文献
998.
Hao Zhang Qianfan Jiang Joseph H. L. Hadden Fang Xie D. Jason Riley 《Advanced functional materials》2021,31(10):2008989
The authors report an ammonia-assisted in situ cation-exchange method for the synthesis of dodecagon N-doped PdCoNi carbon-based nanosheets (Pd-e-NiCo-PBA-C) and explore the catalytic performance. Pd-e-NiCo-PBA-C exerts extremely low overpotential and Tafel slope for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) both in acidic and alkaline media, only 47 mV, 55 mV dec−1 (pH = 0, HER) and 147 mV, 67 mV dec−1 (pH = 14, HER), and 309 mV, 67 mV dec−1 (pH = 14, OER), outperforming commercial IrO2-based and Pt-based catalysts. In addition, after 5000 cycles, the linear sweep voltammetry curve shows a negligible shift, indicating excellent stability performance. To test its overall water-splitting performance, Pd-e-NiCo-PBA-C is applied as both cathode and anode materials. A high current density of 33 mA cm−2 at a battery voltage of 1.6 V is obtained, with the catalytic activity maintained at 97.3% after over 50 h. To get a further insight into the superior OER and HER performance, theoretical calculations are carried out, the better performance originates from the affinity difference of Pd and Ni atoms for gas atoms, and the replacement of inert atoms can decrease the binding energy and enhance the electrocatalytic activity. 相似文献
999.
Aditya Mishra Masoud Alahbakhshi Ross Haroldson Qing Gu Anvar A. Zakhidov Jason D. Slinker 《Advanced functional materials》2021,31(31):2102006
Blue electroluminescence is highly desired for emerging light-emitting devices for display applications and optoelectronics in general. However, saturated, efficient, and stable blue emission has been challenging to achieve, particularly in mixed-halide perovskites, where intrinsic ion motion and halide segregation compromises spectral purity. Here, CsPbBr3−xClx perovskites, polyelectrolytes, and a salt additive are leveraged to demonstrate pure blue emission from single-layer light-emitting electrochemical cells (LECs). The electrolytes transport the ions from salt additives, enhancing charge injection and stabilizing the inherent perovskite emissive lattice for highly pure and sustained blue emission. Substituting Cl into CsPbBr3 tunes the perovskite luminescence from green through blue. Sky blue and saturated blue devices produce International Commission on Illumination coordinates of (0.105, 0.129) and (0.136, 0.068), respectively, with the latter meeting the US National Television Committee standard for the blue primary. Likewise, maximum luminances of 2900 and 1000 cd m−2, external quantum efficiencies (EQEs) of 4.3% and 3.9%, and luminance half-lives of 5.7 and 4.9 h are obtained for sky blue and saturated blue devices, respectively. Polymer and LiPF6 inclusion increases photoluminescence efficiency, suppresses halide segregation, induces thin-film smoothness and uniformity, and reduces crystallite size. Overall, these devices show superior performance among blue perovskite light-emitting diodes (PeLEDs) and general LECs. 相似文献
1000.
Yurou Zhang Dohyung Kim Jung-Ho Yun Jongchul Lim Min-Cherl Jung Xiaoming Wen Jan Seidel Eunyoung Choi Mu Xiao Tengfei Qiu Miaoqiang Lyu EQ Han Mehri Ghasemi Sean Lim Henry J. Snaith Jae Sung Yun Lianzhou Wang 《Advanced functional materials》2021,31(50):2105542
Organometal perovskite single crystals have been recognized as a promising platform for high-performance optoelectronic devices, featuring high crystallinity and stability. However, a high trap density and structural nonuniformity at the surface have been major barriers to the progress of single crystal-based optoelectronic devices. Here, the formation of a unique nanoisland structure is reported at the surface of the facet-controlled cuboid MAPbI3 (MA = CH3NH3+) single crystals through a cation interdiffusion process enabled by energetically vaporized CsI. The interdiffusion of mobile ions between the bulk and the surface is triggered by thermally activated CsI vapor, which reconstructs the surface that is rich in MA and CsI with reduced dangling bonds. Simultaneously, an array of Cs-Pb-rich nanoislands is constructed on the surface of the MAPbI3 single crystals. This newly reconstructed nanoisland surface enhances the light absorbance over 50% and increases the charge carrier mobility from 56 to 93 cm2 V−1 s−1. As confirmed by Kelvin probe force microscopy, the nanoislands form a gradient band bending that prevents recombination of excess carriers, and thus, enhances lateral carrier transport properties. This unique engineering of the single crystal surface provides a pathway towards developing high-quality perovskite single-crystal surface for optoelectronic applications. 相似文献