针对农业场景中草莓因枝叶遮挡、簇生分布及果面反光导致稀疏观测下难以三维重建的问题,本研究基于SA3D(Segment Anything in 3D)框架,在实验室条件下验证了自动化构建高保真草莓三维模型库的可行性。该方法融合DVGO与SAM,利用DVGO从14...针对农业场景中草莓因枝叶遮挡、簇生分布及果面反光导致稀疏观测下难以三维重建的问题,本研究基于SA3D(Segment Anything in 3D)框架,在实验室条件下验证了自动化构建高保真草莓三维模型库的可行性。该方法融合DVGO与SAM,利用DVGO从144张多视角图像中重建保留种子、果蒂等亚毫米细节的三维几何;结合SAM仅需1~2个提示点生成2D掩码,通过Mask逆渲染与跨视角自提示机制实现无标注的三维果实分割。为提升实用性,开发了基于Dash的交互式系统,集成图像上传、位姿估计、重建与分割全流程,支持非专业用户高效建模。实验表明,该方法平均PSNR达20.83 dB(较NeRF提升1.12 dB),IoU均值为0.803,显著增强遮挡与反光区域的重建鲁棒性。所构建的标准化点云库可为表型测量提供基准,并作为几何与语义先验支撑田间稀疏视角重建,服务于智能采摘系统的视觉感知。展开更多
Spectral abscissa(SA)is defined as the real part of the rightmost characteristic root(s)of a dynamical system,and it can be regarded as the decaying rate of the system,the smaller the better from the viewpoint of fast...Spectral abscissa(SA)is defined as the real part of the rightmost characteristic root(s)of a dynamical system,and it can be regarded as the decaying rate of the system,the smaller the better from the viewpoint of fast stabilization.Based on the Puiseux series expansion of complex-valued functions,this paper shows that the SA can be minimized within a given delay interval at values where the characteristic equation has repeated roots with multiplicity 2 or 3.Four sufficient conditions in terms of the partial derivatives of the characteristic function are established for testing whether the SA is minimized or not,and they can be tested directly and easily.展开更多
Present status of the JT-60SA （JT-60 Super Advanced） project, implemented jointly by Europe and Japan since 2007, is described. The design of the main tokamak components was completed in late 2008, and all the scien...Present status of the JT-60SA （JT-60 Super Advanced） project, implemented jointly by Europe and Japan since 2007, is described. The design of the main tokamak components was completed in late 2008, and all the scientific missions are preserved to contribute to ITER and DEMO reactors. The construction of the JT-60SA has begun with procurement activities for the superconducting magnet systems, vacuum vessel, in-vessel components and other components under the relevant procurement arrangements between the implementing agencies of JAEA （Japan Atomic Energy Agency） in Japan and Fusion for Energy in Europe. Designs and developments of the auxiliary heating systems for JT-60SA have been progressing at JAEA so as to provide the total injection power of 41 MW for 100 s.展开更多
基金Project supported by the National Natural Science Foundation of China(No.12072370)。
文摘Spectral abscissa(SA)is defined as the real part of the rightmost characteristic root(s)of a dynamical system,and it can be regarded as the decaying rate of the system,the smaller the better from the viewpoint of fast stabilization.Based on the Puiseux series expansion of complex-valued functions,this paper shows that the SA can be minimized within a given delay interval at values where the characteristic equation has repeated roots with multiplicity 2 or 3.Four sufficient conditions in terms of the partial derivatives of the characteristic function are established for testing whether the SA is minimized or not,and they can be tested directly and easily.
文摘Present status of the JT-60SA （JT-60 Super Advanced） project, implemented jointly by Europe and Japan since 2007, is described. The design of the main tokamak components was completed in late 2008, and all the scientific missions are preserved to contribute to ITER and DEMO reactors. The construction of the JT-60SA has begun with procurement activities for the superconducting magnet systems, vacuum vessel, in-vessel components and other components under the relevant procurement arrangements between the implementing agencies of JAEA （Japan Atomic Energy Agency） in Japan and Fusion for Energy in Europe. Designs and developments of the auxiliary heating systems for JT-60SA have been progressing at JAEA so as to provide the total injection power of 41 MW for 100 s.
