3,843 research outputs found

    Towards Robust Curve Text Detection with Conditional Spatial Expansion

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    It is challenging to detect curve texts due to their irregular shapes and varying sizes. In this paper, we first investigate the deficiency of the existing curve detection methods and then propose a novel Conditional Spatial Expansion (CSE) mechanism to improve the performance of curve text detection. Instead of regarding the curve text detection as a polygon regression or a segmentation problem, we treat it as a region expansion process. Our CSE starts with a seed arbitrarily initialized within a text region and progressively merges neighborhood regions based on the extracted local features by a CNN and contextual information of merged regions. The CSE is highly parameterized and can be seamlessly integrated into existing object detection frameworks. Enhanced by the data-dependent CSE mechanism, our curve text detection system provides robust instance-level text region extraction with minimal post-processing. The analysis experiment shows that our CSE can handle texts with various shapes, sizes, and orientations, and can effectively suppress the false-positives coming from text-like textures or unexpected texts included in the same RoI. Compared with the existing curve text detection algorithms, our method is more robust and enjoys a simpler processing flow. It also creates a new state-of-art performance on curve text benchmarks with F-score of up to 78.4%\%.Comment: This paper has been accepted by IEEE International Conference on Computer Vision and Pattern Recognition (CVPR 2019

    Research on calibration method of electronic control parameters based on engine model

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    The MBC (calibration model-based) toolbox in MATLAB software and Ricardo Wave were used to optimize the power performance of a gasoline engine. In the calibration process, Firstly, the wave simulation model of the engine was established and validated; then, engine operating points were determined by using the design of experiments (DOE) method, and parameters and performance (torque, fuel consumption, power and the cylinder maximum pressure, etc.) of the engine at these operating points were calculated by the simulation model. Finally, the engine mathematical statistical model was established and calibration optimization. The engine ignition advance angle, air-fuel ratio and the torque of the engine were obtained. The results show that the method combined with the modern DoE test design theory and automatic calibration technology not only makes the engine torque from 198 Nm to 215 Nm, but also greatly reduces the test time and improve the calibration efficienc

    Single-pass finite element simulation of ECAP brass

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    Using DEFORM-3D with the single channel brass H63 channel Angle extrusion deformation of computer simulation, such as extrusion process for the change of load, velocity of billet, the effective stress and the distribution of strain rate, grain size billets are analyzed, and the results show that the friction force had a great influence on extrusion process of load, the change of effective stress and strain rate trend, along with the change of extrusion for grain size refinement in a certain extent, but the different location of grain size and distribution is uneven. For the ECAP (equal channel presents pressing) grain refining process of industrial production and application to provide certain theoretical basis

    Ignition timing control strategy based on openECU design

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    Ignition system is the main important part of the engine, and has absolute influence on engine performance. OpenECU for ignition timing strategy on the basis of the design and calibration work, greatly shorten the development difficulty and cycle; machine of a LNG gas ignition timing strategy has carried on the design and optimization, and combining the calculation model for the engine (air intake, compression, power, and exhaust) feedback and verification. It can save a lot of time and resources for experiment if experiments use openECU. It also can monitor the influence of the different inputs conditions on the ignition advance angle. It has realized the map of calibration, greatly shorten the development work and has certain actual application value

    2,2′-Dimethyl-1,1′-[2,2-bis­(bromo­methyl)propane-1,3-di­yl]dibenzimidazole hemihydrate

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    The title compound, C21H22Br2N4·0.5H2O, contains two benzimidazole groups which may provide two potential coordination nodes for the construction of metal–organic frameworks. The mean planes of the two imidazole groups are almost perpendicular, with a dihedral angle of 83.05 (2)°, and adjacent mol­ecules are linked into a one-dimensional chain by π–π stacking inter­actions between imidazole groups of different mol­ecules [centroid-to-centroid distances of 3.834 (2) and 3.522 (2) Å]
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