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The growing size of point clouds enlarges consumptions of storage, transmission, and computation of 3D scenes. Raw data is redundant, noisy, and non-uniform. Therefore, simplifying point clouds for achieving compact, clean, and uniform points is becoming increasingly important for 3D vision and graphics tasks. Previous learning based methods aim to generate fewer points for scene understanding, regardless of the quality of surface reconstruction, leading to results with low reconstruction accuracy and bad point distribution. In this paper, we propose a novel point cloud simplification network (PCS-Net) dedicated to high-quality surface mesh reconstruction while maintaining geometric fidelity. We first learn a sampling matrix in a feature-aware simplification module to reduce the number of points. Then we propose a novel double-scale resampling module to refine the positions of the sampled points, to achieve a uniform distribution. To further retain important shape features, an adaptive sampling strategy with a novel saliency loss is designed. With our PCS-Net, the input non-uniform and noisy point cloud can be simplified in a feature-aware manner, i.e., points near salient features are consolidated but still with uniform distribution locally. Experiments demonstrate the effectiveness of our method and show that we outperform previous simplification or reconstruction-oriented upsampling methods., Comment: 17 pages, 10 figures

Background: The use of standard cytotoxic chemotherapy seems to have reached a “treatment plateau”. The application of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) is a new strategy for non-small-cell lung cancer (NSCLC) therapy. We aimed to comprehensively assess the efficacy and safety of anti-EGFR-mAbs plus chemotherapy as first-line therapy for advanced NSCLC. Methods: According to inclusion and exclusion criteria, we conducted a comprehensive literature search of electronic databases. From the included trials, information on overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs) was extracted. Results: The research showed that compared with chemotherapy alone, anti-EGFR-mAb plus chemotherapy combinations significantly improved OS (HR = 0.88, 95%CI: 0.83-0.94, P = grade 3) that mainly include, leukopenia (OR = 1.53, 95%CI: 1.28-1.82, P

The aim of this paper is to improve the effective width method for distortional buckling strength of cold-formed steel lipped channel members using the energy method and the large deflection theory based on nonlinear post-buckling strength analysis of the partially stiffened element. The accuracy of the proposed method was verified using the finite element method. Comparison on post-distortional buckling strength is conducted between the energy method and the effective width method in the Chinese code Technical code of cold-formed thin-walled steel structures (GB50018-2002). The compared results show that the energy method is very efficient and the effective width method formula in Chinese code can be used to calculate the post-distortional buckling strength. Then, The half-wave length, elastic buckling stress of distortional buckling and the corresponding stability coefficient of partially stiffened elements are developed based on the energy method. With comparison on the calculated results of elastic buckling stress using the proposed method and the Finite Strip Method, suitability and good precision of the developed method are illuminated. Finally, a uniform formula for the stability coefficient of partially stiffened elements considering both local and distortional buckling effect is established. Comparison with experimental results and calculated results predicted with North America specification indicates that the proposed method is reasonable and has a high accuracy and reliability for the distortional buckling load carrying capacities of cold-formed lipped channel members.

High-resistance connection (HRC) is a common electrical fault for the electric machine drive system. This fault can lead to the increased power loss and heat, thus possibly causing the damage of the electric machine drive system due to the excessive temperature. Hence, this paper first proposes a vector control strategy of the surface-mounted permanent magnet synchronous machine (PMSM) drive system with the HRC fault to minimize the copper loss. The mathematical model of the PMSM with the HRC is presented in abc stationary frame. The function relationship between the copper loss and the direct axis current, quadrature axis current, stator resistance, and the additional resistance due to the HRC is established and analyzed. The expression of the direct axis current, which minimizes the copper loss, is deduced under the condition of the HRC in one phase and two phases. Consequently, the proposed vector control strategy for the surface-mounted PMSM driving system is achieved. Both the simulation and experimental results show that the proposed method not only preserves the performance of the conventional vector control method, but also can effectively reduce the copper loss, thus protecting the PMSM from the damage due to the increased temperature possibly caused by the HRC fault.

Arc-length-type and energy-type methods are two main strategies used in structural nonlinear tracing analysis, but the former is widely used due to the explicitness and clarity in conception, as well as the convenience and reliability in calculation. It is very important to trace the complete load-deflection path in order to know comprehensively the characteristics of structures subjected to loads. Unfortunately, the nonlinear analysis techniques are only workable for tracing the limit-point-type equilibrium path. For the bifurcation-point-type path, most of them cannot secure a satisfactory result. In this paper, main arc-length-type methods are reviewed and compared, and the possible reasons of failures in tracing analysis are briefly discussed. Some improvements are proposed, a displacement perturbation method and a force perturbation method are presented for tracing the bifurcation-point-type paths. Finally, two examples are analyzed to verify the ideas, and some conclusions are drawn with respect to the arc-length-type methods.