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Point set is a flexible and lightweight representation widely used for 3D deep learning. However, their discrete nature prevents them from representing continuous and fine geometry, posing a major issue for learning-based shape generation. In this work, we turn the discrete point sets into smooth surfaces by introducing the well-known implicit moving least-squares (IMLS) surface formulation, which naturally defines locally implicit functions on point sets. We incorporate IMLS surface generation into deep neural networks for inheriting both the flexibility of point sets and the high quality of implicit surfaces. Our IMLSNet predicts an octree structure as a scaffold for generating MLS points where needed and characterizes shape geometry with learned local priors. Furthermore, our implicit function evaluation is independent of the neural network once the MLS points are predicted, thus enabling fast runtime evaluation. Our experiments on 3D object reconstruction demonstrate that IMLSNets outperform state-of-the-art learning-based methods in terms of reconstruction quality and computational efficiency. Extensive ablation tests also validate our network design and loss functions., Accepted by CVPR 2021, Code: https://github.com/Andy97/DeepMLS

The performance of seed laser source will have a great impact on the output pulse quality of the master oscillator power amplifier (MOPA) system. Here, we report the influence of the soliton vector features on the pulse uniformity in an all-fiber MOPA configuration. We demonstrated that, although the intensity of the dissipative soliton seed source is uniform, the intensity of the output pulse train from the MOPA will show fluctuations if the soliton polarization state is not locked, i.e., polarization-rotating vector soliton. It is found that the appearance of non-uniform pulse intensity is caused by the combination of the polarization instability and the polarization dependent gain in the polarization maintaining fiber amplifier. The obtained results indicate that the polarization evolution of seed pulsed source is critical to generation of stable pulse train from the MOPA, and also might be useful to the communities dealing with solitons and high-power pulsed fiber lasers.

3D geometric features constitute rich details of polygonal meshes. Their analysis and editing can lead to vivid appearance of shapes and better understanding of the underlying geometry for shape processing and analysis. Traditional mesh smoothing techniques mainly focus on noise filtering and they cannot distinguish different scales of features well, even mixing them up. We present an efficient method to process different scale geometric features based on a novel rolling-guidance normal filter. Given a 3D mesh, our method iteratively applies a joint bilateral filter to face normals at a specified scale, which empirically smooths small-scale geometric features while preserving large-scale features. Our method recovers the mesh from the filtered face normals by a modified Poisson-based gradient deformation that yields better surface quality than existing methods. We demonstrate the effectiveness and superiority of our method on a series of geometry processing tasks, including geometry texture removal and enhancement, coating transfer, mesh segmentation and level-of-detail meshing.

Due to characteristics of random fluctuations and intermittence, large-scale wind power integration will worsen grid stability and power quality. According to grid code, a limit of ramp rate for both 1 minute and 10 minutes should be put on the interconnected power. Using energy storage system is an effective way to smooth the fluctuations of wind farm output. Due to the high cost of the energy storage system, an effective control of the energy state and the BESS charge and discharge rate acquiring a maximum utility of the limited energy storage to improve the output power quality becomes increasingly significant. A coordinated control method for BESS to smooth out wind power fluctuations and to limit wind power ramping rate as required by grid code is proposed, with the BESS energy state well controlled and the predicted wind power used to cope with emergent situation. The effictiveness of the control system is validated through real wind farm cases under MATLAB platform.

The young-old concrete can work together as a whole is the key issue of structural strengthening. Aiming at the technical selection problem appeared frequently in the bridge strengthening about the young-old concrete interface treatments between bonded rebar and grooving, 12 specimens were designed to compare with the shear performance and failure modes of the young-old concrete interface. The test results show that the failure characteristics of specimens which embedded steel bars are ductile, but the failure characteristics of specimens which slotted are brittle and the new concrete in slot position were cut off. And the young-old concrete interface shear strength of the specimens which embedded steel bars was distinctly stronger than that of the slotted specimens. So, the treatment of bonded rebar is proposed during the structural strengthening design. At the same time, the depth and distance of the bonded rebar should be well controlled.

The preexisting strains of structures have some influence on the efficiency of CFRP Laminate. Based on the analysis of the abundant existing research productions, the calculation formulas of CFRP Laminate are proposed based on the supposition of plane section and balance of forces considering the preexisting strain. And the formulas are easy to understand and master for designers. By discussing the relation between the preexisting strain and relative depth of compression area, the essentials of the impact on reinforcement effect of residual strain are confirmed. The results can offer reference bases for strengthening engineering design with CFRP.

The main bridge of Zhengzhou Yellow River 2nd bridge is a concrete filled steel tubulur (CFST) arch bridge. Choosing the main bridge as the research object, the finite element procedure ANSYS was used to establish the 3D finite element dynamic model. In order to analyze the influence of structural Parameters variation on dynamic characteristic,17 different conditions were considered in the calculation and analysis process. The results show that the CFST arch bridge is a flexible structure. The vertical rigidity of the bridge is stronger than the lateral rigidity CFST arch rib. The changes of the transverse brace style have little effect on the vertical rigidity, but have great impacts on the lateral rigidity of the CFST arch rib. It is sensitive on the first step vibration if the bracing tube damage. But the bracing tube damage has little effect on the vertical rigidity. The damages of suspenders and bridge deck slabs influence weakly on the vibration modes.

Many factors need to be considered during the choice of strengthening scheme for arch bridges, and most factors are fuzzy. The reasonable and scientific strengthening scheme is an important precondition to ensure the effectiveness and quality of the strengthening engineering. The elementary objects of the bridges strengthening are effect reliability, economic reasonability, technological feasibility, and convenience of construction, which are used to appraise the strengthening scheme. Based on the basic objective of bridge strengthening, two levels fuzzy comprehensive appraisal index system of strengthening scheme are established, and the best scheme is chosen. Combining the idiographic example of arch bridge reinforcement, the process of fuzzy analytic hierarchy and optimum result is given. The result tests that fuzzy analytic hierarchy method is feasible during the preferred selection on strengthening schemes of arch bridge.

An improved project based on decision trees in noisy environments is proposed for robust endpoints detection. Firstly, the noise level of the environment is estimated by wavelet decomposition, and then whether the denoising process is done according to the noise level is determined. Next, the thresholds are obtained by decision trees for the signal. Finally, endpoints are detected by the double thresholds on different importance of the energy and zero-crossing rate (ZCR) in the corresponding situation. The simulation results indicate that the proposed method based on noise estimation can obtain the same accurate data by computing less than the one with decision trees.

Light absorption plays a key role in photovoltaic devices, especially in thin-film CdTe-based solar cells. Here we study the enhancement of optical absorption in a ultrathin CdTe layer by embedding it into optical magnetic metamaterials. In a periodic metal-CdS-CdTe-metal sandwiched structure, the absorption of transverse magnetic polarized light has been significantly enhanced. The maximum enhancement is around 3 times, which is attributed to the strong local field enhancement in the CdTe thin film. Importantly, due to the coexistence of large electric resonance and magnetic resonance in magnetic metamaterials, the enhancement of light absorption has been obtained in a broadband from 400 nm to 800 nm, which is almost 1.5 times of that of the conventional CdTe-based photovoltaic device and covers the strongest part of the solar spectrum. Moreover, such absorption enhancement is also valid for a wide range of incident angles. We believe that our finding can lead to a variety of important applications in ultrathin CdTe-based solar cell technology.

Here we demonstrate the control of magnetic dipole spontaneous emission at yellow light by polarization-independent hexagonally arrayed nanorods magnetic metamaterials. By embedding a magnetic dipole into a polarization-independent magnetic metamaterial consisting of hexagonal arrays of paired silver nanorods, the radiative emission enhancement and the Purcell factor around 590 nm have been dramatically increased 44 times for a significant general far-field emission enhancement and 57 times for a maximum general magnetic dipole near-field emission enhancement, respectively. Moreover, the polarization-independent enhancements are found to be a robust variation of the dipole’s positions and structure geometries, showing nice fabrication tolerance for practical applications.

Sea cucumber(Apostichopus japonicus) is one of the most important economic aquaculture spe-cies in China.The study on the genome size(C-value) is highly significant because it plays an important role in instructing the hybridization breeding and improved variety breeding program,as well as in esti-mating the cost of the whole genome sequencing project.Previous studies mainly focused on these re-search areas such as ecology,physiology,nutrition etc.However,it is relatively scarce for the accumulation of basic data related to the genome size and characteristics in A.japonipus.Therefore,the measure of ge-nome size for enriching cytogenetics data of this species is meaningful.In this paper,the genome size(C-value) of sea cucumber,A.japonicus was measured through flow cytometry in 52 individuals,which came from aestivation,normal and wild groups,using erythrocyte DNA content of chicken,Gallus domesticus(2.5pg/2C) as internal standard.The result indicates that the C-value of A.japonicus is(0.90± 0.06) pg,equivalent to(880.2±72.26) Mb.And,the C-values of aestivation,normal and wild are(0.93±0.05) pg,(0.90±0.05) pg and(0.84±0.02) pg,respectively.In addition,analyzed by Independent-Samples T Test,it shows that the C-values have no significant difference in aestivation and normal groups,whereas,the C-values of wild group and that reared in captivity group have significant difference.In other words,there is no correlation between genome size and the physiology factor-aestivation,while the stability of envi-ronment factors has certain influences on genome size variation.Moreover,the development of C-value measure method was elucidated in detail,in the meanwhile,the relationship between C-value and the evo-lution in Holothuroidea was discussed in combination with genome size of other types of sea cucumber.