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基于偏正结构表示的加工命名实体识别方法

计算机集成制造系统 2024年第3期30卷 958-967页

作者：王素琴王钰珏石敏朱登明李兆歆华北电力大学控制与计算机工程学院北京102206 中国农业科学院农业信息研究所北京100081

制造企业积累大量的零件加工经验多以文本形式存在,如何从文本中挖掘出高质量的零件加工知识是个尚待解决的问题。针对待识别实体存在的偏正结构特征,导致实体边界界定模糊的问题,提出一种多网络协调的中文命名实体识别方法。在BERT生... 详细信息

制造企业积累大量的零件加工经验多以文本形式存在,如何从文本中挖掘出高质量的零件加工知识是个尚待解决的问题。针对待识别实体存在的偏正结构特征,导致实体边界界定模糊的问题,提出一种多网络协调的中文命名实体识别方法。在BERT生成字向量的过程中,通过领域自适应方法,提高字向量对工艺实体的表征能力,同时,在BiLSTM-CRF模型中引入注意力机制和多门控制的混合专家网络捕获上下文特征与实体信息。实验表明,较于当前主流的命名实体识别模型,该文提出的方法对机械零件加工实体识别的F1值达到80.15%,取得优于其他模型的最好性能。

关键词：中文命名实体识别机械零件加工多门控制的混合专家网络领域自适应

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一种带高光处理的无缝纹理映射方法

图学学报 2024年第1期45卷 148-158页

作者：石敏王炳祺李兆歆朱登明华北电力大学控制与计算机工程学院北京102206 中国农业科学院农业信息研究所北京100081 中国科学院计算技术研究所前瞻研究实验室北京100190 太仓中科信息技术研究院江苏太仓215400

纹理映射作为三维重建的重要步骤,直接关系到生成模型的视觉效果。传统的纹理映射方法通常使用简单的混合方法来获取表面纹理。通过将模型表面投影到每个纹理图像上来获取相应的纹理区域,然后将它们混合在一起以获取表面纹理。然而,由... 详细信息

纹理映射作为三维重建的重要步骤,直接关系到生成模型的视觉效果。传统的纹理映射方法通常使用简单的混合方法来获取表面纹理。通过将模型表面投影到每个纹理图像上来获取相应的纹理区域,然后将它们混合在一起以获取表面纹理。然而,由于相机位姿的不准确性,纹理映射结果存在明显的模糊和鬼影等问题。此外,在高光环境下获取的纹理图像很容易包含高光区域,最终导致纹理颜色的丢失,降低纹理的真实性。为了解决这些问题,提出了一种无缝纹理映射方法,可以有效消除高光反射。通过衡量纹理图像的质量,为每个模型表面选择最佳的纹理图像,并利用色度一致性约束优化的相机位姿以消除明显的纹理错位。针对高光问题,提出了一个高光处理模块,使用多视图图像信息并基于双色反射模型定位和处理高光纹理。最后,对纹理图进行纹理颜色一致性调整,以处理纹理之间的颜色差异。实验结果表明,与现有方法相比,提出的算法可以有效消除高光反射的影响,从而获得更好的纹理映射结果。

关键词：三维重建纹理映射高光处理纹理渲染位姿校正

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河蟹池塘微孔增氧高效生态养殖技术

安徽农学通报 2024年第9期30卷 54-57页

作者：李兆新淮南市毛集社会发展综合实验区农业发展局安徽淮南232000

微孔增氧养殖技术能有效提高池水中的溶氧水平,适当加大池塘养殖密度,提高养殖产量,增加经济效益。为提高河蟹养殖品质及产量,本文结合河蟹养殖实践,对河蟹池塘微孔增氧高效生态养殖技术要点进行总结分析,包括池塘选择与改造管理、河蟹... 详细信息

微孔增氧养殖技术能有效提高池水中的溶氧水平,适当加大池塘养殖密度,提高养殖产量,增加经济效益。为提高河蟹养殖品质及产量,本文结合河蟹养殖实践,对河蟹池塘微孔增氧高效生态养殖技术要点进行总结分析,包括池塘选择与改造管理、河蟹苗投放、池塘管理以及河蟹捕捞等;应用效果分析表明,池塘微孔增氧养殖技术综合利润较常规养殖方式增加明显。可结合实际情况推广池塘微孔增氧养殖模式。

关键词：河蟹池塘微孔增氧生态养殖溶解氧养殖效益

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稻虾共育高效生态种养技术

安徽农学通报 2024年第10期30卷 15-18页

作者：李兆新淮南市毛集社会发展综合实验区农业发展局安徽淮南232000

稻虾共育是一种立体高效的新型种养模式。本文结合生产实践,从稻田选择、虾沟开挖、防逃设施固定、虾苗田管理、成虾场管理、日常管理以及成虾捕捞和亲虾留存方面,总结分析了稻虾共育高效生态种养技术要点,并分别从生态效益、经济效益... 详细信息

稻虾共育是一种立体高效的新型种养模式。本文结合生产实践,从稻田选择、虾沟开挖、防逃设施固定、虾苗田管理、成虾场管理、日常管理以及成虾捕捞和亲虾留存方面,总结分析了稻虾共育高效生态种养技术要点,并分别从生态效益、经济效益和综合效益3个方面探讨了稻虾共育的生态效益、经济效益和综合效益,为该技术的进一步推广应用提供参考。

关键词：稻虾共育生态种养绿色农业稻田改造种养管理

Robust and efficient edge-based visual odometry

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Computational Visual Media 2022年第3期8卷 467-481页

作者： Feihu Yan zhaoxin li Zhong Zhou State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China Institute of Computing Technology Chinese Academy ofSciencesBeijing 100190China

Visual odometry,which aims to estimate relative camera motion between sequential video frames,has been widely used in the fields of augmented reality,virtual reality,and autonomous ***,it is still quite challenging for stateof-the-art approaches to handle low-texture *** this paper,we propose a robust and efficient visual odometry algorithm that directly utilizes edge pixels to track camera *** contrast to direct methods,we choose reprojection error to construct the optimization energy,which can effectively cope with illumination *** distance transform map built upon edge detection for each frame is used to improve tracking efficiency.A novel weighted edge alignment method together with sliding window optimization is proposed to further improve the *** on public datasets show that the method is comparable to stateof-the-art methods in terms of tracking accuracy,while being faster and more robust.

关键词： visual odometry(VO) edge structure distance transform low-texture

ITF in a coupled GCM and its interannual variability related to ENSO and IOD

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Acta Oceanologica Sinica 2006年第1期25卷 32-47页

作者： li Wei li zhaoxin liU Hailong State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Laboratoire de Meteorologie Dynamique CNRS Universite Pierre et Marie Curie Paris France

The interannual variability of the mass transport of the Indonesian Throughflow （ITF） is very possible to be connected with the E1 Nino-Southem Oscillation （ENSO） in the Pacific Ocean and/or the Indian Ocean Dipole （IOD）. The IPSL （Institute Pierre-Simon Laplace） coupled general circulation model （CGCM） was employed to examine the interannual variability of the ITF and understand its relationship with the climatic variation in both the basins. A 1 000 a integration was conducted and an annual mean model output was utilized. The pathways of the simulated ITF are reasonable within the Indonesian seas. The major transport occurs in the upper 300 m, with an annual mean transport of 15.68×106 m^3/s, among which the 13.83×1^6 m^3/s through the Makassar Strait is the principal component. The interannual variability of the ITF transport is significant in a 2～4 a period. The relationship between sea level differences across the Indonesian seas （sites in the western Pacific north of the equator and south coast of Java, respectively） and the ITF transport is straightforward on the interannual time-scale with a simultaneous correlation of 0.82. Further investigation indicates that the preceding climatic variation in the tropical Pacific is related to the ITF transport anomaly. The ENSO-like pattem leads the extreme of ITF transport by 1 a, with the correlation between a Nifio 3 SST index and the ITF transport of 0.37. It means that there tends to be an E1 Nino anomaly in the Pacific 1 a before a large ITF transport. The simultaneous correlation between the Nino 3 SST index and the ITF transport is -0.34. The patterns of sea surface temperature and sea surface height are, however, not the typical ENSO anomaly. The ITF transport is more related to the concurrent interannual variability over the Indian Ocean. The simultaneous correlation between the ITF transport and the dipole mode index is 0.46 and the pattem of upper layer anomaly is much like that of the IOD.

关键词： Indonesian Throughflow ENSO interannual variability

Impacts of Upper Tropospheric Cooling upon the Late Spring Drought in East Asia Simulated by a Regional Climate Model

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Advances in Atmospheric Sciences 2008年第4期25卷 555-562页

作者：辛晓歌 zhaoxin li 宇如聪周天军 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Graduate University of Chinese Academy of Sciences Beijing 100049 Laboratoire de Mdteorologie Dynamique IPSL/CNRS Universite Pierre et Marie Curie Paris France National Climate Center China Meteorological Administration Beijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081

Responses of late spring （21 April 20 May） rainfall to the upper tropospheric cooling over East Asia are investigated with a regional climate model based on Laboratoire de M6t6orologie Dynamique Zoom （LMDZ4-RCM）. A control experiment is performed with two runs driven by the mean ERA-40 data during 1958-1977 and 1981 2000, respectively. The model reproduces the major decadal-scale circulation changes in late spring over East Asia, including a cooling in the upper troposphere and an anomalous meridional cell. Accordingly, the precipitation decrease is also captured in the southeast of the upper-level cooling region. To quantify the role of the upper-level cooling in the drought mechanism, a sensitivity experiment is further conducted with the cooling imposed in the upper troposphere. It is demonstrated that the upper-level cooling can generate the anomalous meridional cell and consequently the drought to the southeast of the cooling center. Therefore, upper tropospheric cooling should have played a dominant role in the observed late spring drought over Southeast China in recent decades.

关键词： Southeast China spring drought inter-decadal variability regional climate modeling

Theoretical analysis on the deformation characteristics of coal wall in a longwall top coal caving face

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International Journal of Mining Science and Technology 2015年第2期25卷 199-204页

作者： Bai Qingsheng Tu Shihao li zhaoxin Tu Hongsheng School of Mines Key Laboratory of Deep Coal ResourceMinistry of EducationChina University of Mining & Technology

Against the background of analyzing coal wall stability in 14101 fully mechanized longwall top coal caving face in Majialiang coal mine,based on the torque equilibrium of the coal wall,shield support and the roof strata,an elastic mechanics model was established to calculate the stress applied on the coal *** displacement method was used to obtain the stress and deformation distributions of the coal *** study also researched the influence of support resistance,protective pressure to the coal wall,fracture position of the main roof and mining height on the coal wall *** following conclusions are drawn:(1) The shorter the distance from the longwall face,the greater the vertical compressive stress and horizontal tensile stress borne by the coal *** coal wall is prone to failure in the form of compressive-shear and tension;(2) With increasing support resistance,the revolution angle of the main roof decreases *** the support resistance and protective force supplied by the face guard increases,the maximum deformation of the coal wall decreases linearly;(3) As the face approaches the fracture position of the main roof,coal wall horizontal deformation increases significantly,and the coal wall is prone to instability;and(4) The best mining height of 14101 longwall face is 3.0 m.

关键词： Longwall top coal caving face Coal wall deformation Torque equilibrium Displacement method Parametric analysis

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惯性约束聚变的电磁屏蔽仿真

安全与电磁兼容 2024年第2期 43-47,68页

作者：李兆鑫谢雪丹辛鑫山西能源学院

惯性约束核聚变的激光靶耦合过程产生的电磁脉冲会强烈干扰实验诊断设备的正常运行。为此,用B-dot天线采集了神光Ⅱ装置近靶点处激光与靶耦合产生的电磁脉冲信号,简单分析了6个打靶发次的电磁脉冲实验数据。并提出了加装铜制材料作为屏... 详细信息

惯性约束核聚变的激光靶耦合过程产生的电磁脉冲会强烈干扰实验诊断设备的正常运行。为此,用B-dot天线采集了神光Ⅱ装置近靶点处激光与靶耦合产生的电磁脉冲信号,简单分析了6个打靶发次的电磁脉冲实验数据。并提出了加装铜制材料作为屏蔽装置以削弱电磁脉冲干扰的设计。借助ANSYS多物理场仿真软件对加装屏蔽板后不同电压下的电势分布进行了仿真,仿真结果表明,铜屏蔽板对220 V/380 V电压下的激励均具有良好的屏蔽效果,电势大小均降低到15 V以下。

关键词：惯性约束聚变电磁脉冲电磁屏蔽 ANSYS