We decrease the rms mean curvature and area of a variable surface with a fixed boundary by iterating a few times through a curvature-based variational algorithm. For a boundary with a known minimal surface, starting w...
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We decrease the rms mean curvature and area of a variable surface with a fixed boundary by iterating a few times through a curvature-based variational algorithm. For a boundary with a known minimal surface, starting with a deliberately chosen non-minimal surface, we achieve up to 65 percent of the total possible decrease in area. When we apply our algorithm to a bilinear interpolant bounded by four non-coplanar straight lines, the area decrease by the same algorithm is only 0.116179 percent of the original value. This relative stability suggests that the bilinear interpolant is already a quasi-minimal surface. (C) 2015 Elsevier Ltd. All rights reserved.
In a flexible DC distribution system, the converters will be blocked within a few milliseconds for its self-protection during the DC line fault. Using such a short period of the fault transient, it is challenging to i...
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In a flexible DC distribution system, the converters will be blocked within a few milliseconds for its self-protection during the DC line fault. Using such a short period of the fault transient, it is challenging to identify the correct faulted area. In this study, the characteristics of fault current waveform and sudden change are analysed in detail, and the curvature algorithm is used to extract the current waveform difference between the internal and external faults. Then this study proposes a new scheme for the multi-terminal DC distribution system. This protection is developed based on natural variation characteristics and curvature of DC current under fault transients. Compared with the di/dt protection to correctly identify internal high impedance fault. The proposed method could identify faults with different high resistances quickly, meet the speed and reliability requirement of the DC distribution system. Numerous tests are carried out in both simulation and hardware experiments. Testing results derived under various fault conditions have demonstrated that internal faults with different impedances can be correctly identified by employing the proposed protection scheme.
To solve the recognition of road sign with an intelligent vehicle in vision-based navigation, road sign extraction and matching techniques required in outdoor scene was proposed in this paper. The method of the improv...
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ISBN:
(纸本)9789811063855;9789811063848
To solve the recognition of road sign with an intelligent vehicle in vision-based navigation, road sign extraction and matching techniques required in outdoor scene was proposed in this paper. The method of the improved curvature based on feature extraction and binary description took the advantage of reasonable features distribution to overcome the problems of traditional features uneven distribution. Binary description method was represented to solve the real-time problem of feature matching. Through the validity and real-time performance of different algorithms are compared by experiments and indicate that the method can not only overcome negative influences from the disturb of non-targets, while spending on average only 46 ms processing each frame, but also meet the requirements of robustness, real-time, and accuracy.
To solve the recognition of road sign with an intelligent vehicle in vision-based navigation, road sign extraction and matching techniques required in outdoor scene was proposed in this paper. The method of the improv...
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To solve the recognition of road sign with an intelligent vehicle in vision-based navigation, road sign extraction and matching techniques required in outdoor scene was proposed in this paper. The method of the improved curvature based on feature extraction and binary description took the advantage of reasonable features distribution to overcome the problems of traditional features uneven distribution. Binary description method was represented to solve the real-time problem of feature matching. Through the validity and real-time performance of different algorithms are compared by experiments and indicate that the method can not only overcome negative influences from the disturb of non-targets, while spending on average only 46 ms processing each frame, but also meet the requirements of robustness, real-time, and accuracy.
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