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Multisensor image fusion algorithm using nonseparable wavelet frame transform 被引量:1
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作者 Li Zhenhua Jing Zhongliang Wang Hong Sun Shaoyuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期728-732,共5页
A muitisensor image fusion algorithm is described using 2-dimensional nonseparable wavelet frame (NWF) transform. The source muitisensor images are first decomposed by the NWF transform. Then, the NWF transform coef... A muitisensor image fusion algorithm is described using 2-dimensional nonseparable wavelet frame (NWF) transform. The source muitisensor images are first decomposed by the NWF transform. Then, the NWF transform coefficients of the source images are combined into the composite NWF transform coefficients. Inverse NWF transform is performed on the composite NWF transform coefficients in order to obtain the intermediate fused image. Finally, intensity adjustment is applied to the intermediate fused image in order to maintain the dynamic intensity range. Experiment resuits using real data show that the proposed algorithm works well in muitisensor image fusion. 展开更多
关键词 MULTISENSOR image fusion image processing nonseparable wavelet frame transform.
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Ward identities under the frame transformations in curved space-time
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作者 Susobhan Mandal 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第9期107-117,共11页
Scalar-tensor theories of gravity are considered to be competitors to Einstein's theory of general relativity for the description of classical gravity,as they are used to build feasible models for cosmic inflation... Scalar-tensor theories of gravity are considered to be competitors to Einstein's theory of general relativity for the description of classical gravity,as they are used to build feasible models for cosmic inflation.These theories can be formulated both in the Jordan and Einstein frame,which are related by a Weyl transformation with a field transformation,known together as a frame transformation.These theories formulated in the above two frames are often considered to be equivalent from the point of view of classical theory.However,this is no longer true from the quantum field theoretical perspective.In the present article,we show that the Ward identities derived in the above two frames are not connected through the frame transformation.This shows that the quantum field theories formulated in these two frames are not equivalent to each other.Moreover,this inequivalence is also shown by comparing the effective actions derived in these two frames. 展开更多
关键词 ward identities frame transformations curved spacetime
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Exact Solution of Second Grade Fluid in a Rotating Frame through Porous Media Using Hodograph Transformation Method
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作者 Sayantan Sil Manoj Kumar 《Journal of Applied Mathematics and Physics》 2015年第11期1443-1453,共11页
In this paper exact solution for a homogenous incompressible, second grade fluid in a rotating frame through porous media has been provided using hodograph-Legendre transformation method. Results are summarised in the... In this paper exact solution for a homogenous incompressible, second grade fluid in a rotating frame through porous media has been provided using hodograph-Legendre transformation method. Results are summarised in the form of theorems. Two examples have been taken and streamline patterns are shown for the solutions. 展开更多
关键词 Non-Newtonian Fluid ROTATING frame Hodograph transformation POROUS Media EXACT Solution
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The Incompatibinty between Lorentz Transformations and the Inertial Frame of Reference
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《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第1期77-81,共5页
TheIncompatibintybetweenLorentzTransformationsandtheInertialFrameofReferenceG.Gabed,InSI.OfPhysi's,Unly.COlO... TheIncompatibintybetweenLorentzTransformationsandtheInertialFrameofReferenceG.Gabed,InSI.OfPhysi's,Unly.COlOgneZulpl'cherSir.... 展开更多
关键词 The Incompatibinty between Lorentz transformations and the Inertial frame of
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A Robust Digital Watermarking Algorithm Based on Finite-Set Discrete Radon Transform Tight Frame
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作者 Jiangui Zhang Huibin Qi 《Journal of Computer and Communications》 2020年第12期123-133,共11页
<div style="text-align:justify;"> Digital watermarking technology plays a powerful role in the effective protection of digital media copyright, image authentication, image sharing, image information tr... <div style="text-align:justify;"> Digital watermarking technology plays a powerful role in the effective protection of digital media copyright, image authentication, image sharing, image information transmission and other fields. Driven by strong demand, digital image watermarking technology has aroused widespread research interest and has gradually developed into one of the most active research directions in information science. In this paper, we present a novel robust digital watermarking algorithm based on discrete radon transform tight frame in finite-set (FDRT). FDRT of the zero mean image is a tight frame, the frame boundary <em><strong>A</strong></em> = <em><strong>B</strong></em> = 1, the dual of the frame is itself. The decomposition and reconstruction of the FDRT tight frame will not cause the phenomenon of image distortion. The embedding of hidden watermark is to add a weak signal to the strong background of the original image. Watermark extraction is to effectively identify the embedded weak signal. The feasibility of the watermarking algorithm is analyzed from two aspects of information hiding and robustness. We select the independent Gaussian random vector as the watermark series, and the peak signal-to-noise ratio (PSNR) as the visual degradation criterion of the watermark image. Basing the FDRT compact stand dual operator, we derived the relationship among the strength parameter, square sum of watermark series, the PSNR. Using Checkmark system, the simulation results show that the algorithm is robust enough to some very important image processing attacks such as lossy compression, MAP, filtering, segmentation, edge enhancement, jitter, quadratic modulation and general geometric attack (scaling, rotation, shearing), etc. </div> 展开更多
关键词 Digital Watermarking Data Mining Discrete Radon transform Tight frame Copyright Protection Information Hiding Finite-Set
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基于机载视觉无锚框Transformer的架空输电线路高空作业危险行为辨识
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作者 陈增烁 《科技创新与应用》 2025年第36期144-147,共4页
在分析架空输电线路高空作业危险行为的过程中,主要依赖深度卷积神经网络进行辨识,但该方法依赖预设锚框匹配目标,在面对复杂目标时,辨识结果的平均精度(AP)值较低。因此,提出基于机载视觉无锚框Transformer的架空输电线路高空作业危险... 在分析架空输电线路高空作业危险行为的过程中,主要依赖深度卷积神经网络进行辨识,但该方法依赖预设锚框匹配目标,在面对复杂目标时,辨识结果的平均精度(AP)值较低。因此,提出基于机载视觉无锚框Transformer的架空输电线路高空作业危险行为辨识方法。通过叠加边缘特征、融合梯度特征和灰度特征,获取增强后的高空作业场景机载视觉图像。针对增强图像进行分块处理,并观察不同图像区域之间的颜色差异,从整体图像中提取感兴趣区域。将感兴趣区域图像输入无锚框Transformer网络模型中,通过深层次特征提取和回归分类学习,辨识出高空作业危险行为。实验结果表明,该方法辨识结果AP值达到0.91,这证明其优越性。 展开更多
关键词 机载视觉 无锚框transformer 架空输电线路 高空作业 危险行为 感兴趣区域
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基于特征增强和历史帧选择的Transformer视觉跟踪算法 被引量:5
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作者 侯志强 杨晓麟 +3 位作者 马素刚 王云龙 余旺盛 王昀琛 《控制与决策》 EI CSCD 北大核心 2024年第10期3506-3512,共7页
为进一步提升跟踪算法在历史帧信息利用和目标特征表达方面的性能,提出基于特征增强和历史帧选择的Transformer视觉跟踪算法(feature enhancement and history frame selection based Transformer visual tracking, FEHST).首先,在骨干... 为进一步提升跟踪算法在历史帧信息利用和目标特征表达方面的性能,提出基于特征增强和历史帧选择的Transformer视觉跟踪算法(feature enhancement and history frame selection based Transformer visual tracking, FEHST).首先,在骨干网络中引入动态预测模块,通过稀疏化策略提高自注意力机制的计算效率,聚焦目标区域特征;其次,提出特征增强模块,将局部信息与全局信息的优势相结合,提升特征的表达能力;最后,采用自适应历史帧选择策略,提升跟踪器对目标动态信息的关注.在LaSOT、TrackingNet、GOT-10K和OTB100等数据集上进行了大量的实验,实验结果显示,在LaSOT、TrackingNet、OTB100上分别取得70.1%、83.0%和71.6%的成功率,在GOT-10K上取得71.4%的平均重叠度,并能以27 FPS的速度运行. 展开更多
关键词 计算机视觉 视觉跟踪 深度学习 注意力机制 历史帧选择 transformER
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改进视觉Transformer的视频插帧方法 被引量:1
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作者 石昌通 单鸿涛 +3 位作者 郑光远 张玉金 刘怀远 宗智浩 《计算机应用研究》 CSCD 北大核心 2024年第4期1252-1257,共6页
针对现有的视频插帧方法无法有效处理大运动和复杂运动场景的问题,提出了一种改进视觉Transformer的视频插帧方法。该方法融合了基于跨尺度窗口的注意力和可分离的时空局部注意力,增大了注意力的感受野并聚合了多尺度信息;对时空依赖和... 针对现有的视频插帧方法无法有效处理大运动和复杂运动场景的问题,提出了一种改进视觉Transformer的视频插帧方法。该方法融合了基于跨尺度窗口的注意力和可分离的时空局部注意力,增大了注意力的感受野并聚合了多尺度信息;对时空依赖和远程像素依赖关系进行联合建模,进而增强了模型对大运动场景的处理能力。实验结果表明,该方法在Vimeo90K测试集和DAVIS数据集上的PSNR指标分别达到了37.13 dB和28.28 dB,SSIM指标分别达到了0.978和0.891。同时,可视化结果表明,该方法针对存在大运动、复杂运动和遮挡场景的视频能产生清晰合理的插帧结果。 展开更多
关键词 视频插帧 transformER 基于跨尺度窗口的注意力 大运动 复杂运动
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Automatic Method for Synchronizing Workpiece Frames in Twin-robot Nondestructive Testing System 被引量:6
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作者 LU Zongxing XU Chunguang +2 位作者 PAN Qinxue MENG Fanwu LI Xinliang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期860-868,共9页
The workpiece frames relative to each robot base frame should be known in advance for the proper operation of twin-robot nondestructive testing system. However, when two robots are separated from the workpieces, the t... The workpiece frames relative to each robot base frame should be known in advance for the proper operation of twin-robot nondestructive testing system. However, when two robots are separated from the workpieces, the twin robots cannot reach the same point to complete the process of workpiece frame positioning. Thus, a new method is proposed to solve the problem of coincidence between workpiece frames. Transformation between two robot base frames is initiated by measuring the coordinate values of three non-collinear calibration points. The relationship between the workpiece frame and that of the slave robot base frame is then determined according to the known transformation of two robot base frames, as well as the relationship between the workpiece frame and that of the master robot base frame. Only one robot is required to actually measure the coordinate values of the calibration points on the workpiece. This requirement is beneficial when one of the robots cannot reach and measure the calibration points. The coordinate values of the calibration points are derived by driving the robot hand to the points and recording the values of top center point(TCP) coordinates. The translation and rotation matrices relate either the two robot base frames or the workpiece and master robot. The coordinated are solved using the measured values of the calibration points according to the Cartesian transformation principle. An optimal method is developed based on exponential mapping of Lie algebra to ensure that the rotation matrix is orthogonal. Experimental results show that this method involves fewer steps, offers significant advantages in terms of operation and time-saving. A method used to synchronize workpiece frames in twin-robot system automatically is presented. 展开更多
关键词 twin-robot system workpiece frame coordinate transformation matrix orthogonal Lie algebra
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Some New Inequalities for Wavelet Frames on Local Fields 被引量:1
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作者 Firdous A.Shah Owais Ahmad Neyaz A.Sheikh 《Analysis in Theory and Applications》 CSCD 2017年第2期134-148,共15页
Wavelet frames have gained considerable popularity during the past decade, primarily due to their substantiated applications in diverse and widespread fields of science and engineering. Finding general and verifiable ... Wavelet frames have gained considerable popularity during the past decade, primarily due to their substantiated applications in diverse and widespread fields of science and engineering. Finding general and verifiable conditions which imply that the wavelet systems are wavelet frames is among the core problems in time-frequency analysis. In this article, we establish some new inequalities for wavelet frames on local fields of positive characteristic by means of the Fourier transform. As an application, an improved version of the Li-Jiang inequality for wavelet frames on local fields is obtained. 展开更多
关键词 frame INEQUALITIES wavelet frame local field Fourier transform.
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On Characterization of Nonuniform Tight Wavelet Frames on Local Fields
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作者 Owais Ahmad Neyaz A.Sheikh 《Analysis in Theory and Applications》 CSCD 2018年第2期135-146,共12页
In this article, we introduce a notion of nonuniform wavelet frames on local fields of positive characteristic. Furthermore, we gave a complete characterization of tight nonuniform wavelet frames on local fields of po... In this article, we introduce a notion of nonuniform wavelet frames on local fields of positive characteristic. Furthermore, we gave a complete characterization of tight nonuniform wavelet frames on local fields of positive characteristic via Fourier transform. Our results also hold for the Cantor dyadic group and the Vilenkin groups as they are local fields of positive characteristic. 展开更多
关键词 NONUNIFORM WAVELET frame TIGHT WAVELET frame FOURIER transform.local field
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框指令FRAME在数控铣削齿块中的应用
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作者 章晓东 《现代制造工程》 CSCD 2006年第5期59-60,共2页
通过对框指令操作的分析提出一种新方法,用以替代在数控镗铣床回转工作台上加工大模数齿块中,齿块中心与工作台回转中心不重合时所需进行的大量的坐标参数计算。
关键词 框指令frame 大模数齿块 坐标变换
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A Novel Frame Error Concealment Scheme Based on Gain Control for TCX Audio Codec
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作者 XIANG Kai HU Ruimin 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2016年第2期133-138,共6页
A novel frame error concealment scheme is proposed to improve the decoded audio quality of the receiver for transform coded excitation(TCX)audio codec.This scheme,which is a gain control approach based on the stabil... A novel frame error concealment scheme is proposed to improve the decoded audio quality of the receiver for transform coded excitation(TCX)audio codec.This scheme,which is a gain control approach based on the stability of linear predictive coding(LPC)filter,predicts the lost frames by utilizing the linear spectrum frequency and different continuous attenuation factor of different kinds of lost frames.Signal noise ratio(SNR)test and multiple stimuli with hidden reference and anchor(MUSHRA)test are conducted to evaluate the performance of this approach in adaptive multi-rate wideband plus(AMR-WB+)audio codec.Compared with the original frame error concealment scheme,our scheme achieves better audio recovery quality in AMR-WB+audio codec. 展开更多
关键词 frame error concealment audio codec transform coded excitation (TCX)
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中国高精度速度场建立方法及其在框架转换中的应用 被引量:2
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作者 杨瀚融 厉芳婷 +3 位作者 王恒毅 魏以宽 陈华 姜卫平 《武汉大学学报(信息科学版)》 北大核心 2025年第4期706-713,共8页
高精度全球卫星导航系统(global navigation satellite system, GNSS)定位成果一般在国际地球参考框架(international terrestrial reference frame,ITRF)下表达,但是中国测绘成果要求采用2000国家大地坐标系(China geodetic coordinate... 高精度全球卫星导航系统(global navigation satellite system, GNSS)定位成果一般在国际地球参考框架(international terrestrial reference frame,ITRF)下表达,但是中国测绘成果要求采用2000国家大地坐标系(China geodetic coordinate system 2000,CGCS2000),高精度速度场模型是实现两者转换的关键。目前大多研究没有考虑不同函数拟合方法在不同速度方向上的表现,也没有深入研究同一方法不同的参数设置对速度场构建的影响。因此,根据中国大陆地壳运动监测网(crustal movement observation network of China, CMONOC)的260多个连续运行基准站和中国境内及周边地区的90个国际GNSS服务站数据,基于张力样条函数法和克里金法,分别采用不同的参数设置构建了覆盖全国的1 mm级高精度速度场模型,确立了在东、北、天3方向精度最高的3种方法,并用这3种方法构建组合速度场模型。将该模型应用于全国范围连续运行基准站的ITRF2014和CGCS2000坐标转换。研究结果表明,所建立的组合速度场整体转换精度为2.261 cm,单一方向分量的转换精度维持在1.3 cm左右,能实现中国境内大范围测绘成果厘米级精度的基准转换。 展开更多
关键词 CMONOC 速度场 张力样条函数法 克里金法 框架转换
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上承式拱形变高钢桁组合连续梁施工关键技术
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作者 朱云萍 胡杰 涂满明 《世界桥梁》 北大核心 2025年第3期26-32,共7页
延崇高速砖楼特大桥主桥采用(65+120+65) m上承式拱形变高钢桁组合连续梁,双幅分离,分别位于平面圆曲线、缓和曲线及直线段上,平面以直代曲、桥面超高及超高过渡变化使得钢结构和桥面系异常复杂,且钢桁梁杆件种类和数量繁多、空间结构... 延崇高速砖楼特大桥主桥采用(65+120+65) m上承式拱形变高钢桁组合连续梁,双幅分离,分别位于平面圆曲线、缓和曲线及直线段上,平面以直代曲、桥面超高及超高过渡变化使得钢结构和桥面系异常复杂,且钢桁梁杆件种类和数量繁多、空间结构复杂。主梁施工采用双幅共用塔吊+履带吊悬拼方案,经济适用性强,解决了山区施工条件受限难题;主墩处采用托架+倒T形立柱精调系统,确保平、纵面曲线连续钢桁梁悬拼起始节间安装精度,以及双悬臂架设安全性;杆件连接时利用标准冲钉控制杆件形位,通过控制安装拱度和桥面轴线实现高精度线形控制;采用Z形托架辅助边跨上墩,通过边跨压重、合龙口斜角对拉技术确保合龙段快速精确安装,完成结构体系转换;采用吊架法施工桥面悬臂现浇段混凝土,实现平面曲线线形和桥面超高过渡需求。 展开更多
关键词 钢桁组合连续梁 悬臂拼装 托架 精调系统 线形控制 体系转换 吊架法 施工技术
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The Explanation of the Michelson-Morley Experiment Results by Means Universal Frame of Reference
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作者 Karol Szostek Roman Szostek 《Journal of Modern Physics》 2017年第11期1868-1883,共16页
It is commonly thought that the Michelson-Morley experiment from 1887 and Kennedy-Thorndike experiment from 1932 demonstrated that the universal frame of reference (ether) does not exist and that the velocity of light... It is commonly thought that the Michelson-Morley experiment from 1887 and Kennedy-Thorndike experiment from 1932 demonstrated that the universal frame of reference (ether) does not exist and that the velocity of light in vacuum is absolutely constant. The analysis of this experiment led to the creation of the Special Theory of Relativity (STR). The article explains why Michelson-Morley and Kennedy-Thorndike experiments could not detect the universal frame of reference. In this article, a different transformation of time and position than the Lorentz transformation is derived on the basis of the geometric analysis of the Michelson-Morley and Kennedy-Thorndike experiments. The transformation is derived based on the assumption that the universal frame of reference (UFR) exists. UFR is a frame of reference in which the velocity of light is constant in every direction. In inertial frames of reference moving in the UFR, the velocity of light may be different. The article has derived the formula for relative speed and patterns for the maximum and minimum speed of light that can be measured in the inertial system. Finally, the anisotropy of the microwave background radiation has been explained by using the presented theory. According to the body kinematics model presented in this article, anisotropy of cosmic microwave background is the Doppler effect for observer moving in the UFR. 展开更多
关键词 Kinematics of Bodies UNIVERSAL frame of Reference COORDINATE and Time transformation One-Way Speed of Light Anisotropy of COSMIC Microwave Background
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A Characterization of MRA Based Wavelet Frames Generated by the Walsh Polynomials
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作者 Firdous A. Shah Sunita Goyal 《Analysis in Theory and Applications》 CSCD 2016年第2期164-173,共10页
Extension Principles play a significant role in the construction of MRA based wavelet frames and have attracted much attention for their potential applications in various scientific fields. A novel and simple procedur... Extension Principles play a significant role in the construction of MRA based wavelet frames and have attracted much attention for their potential applications in various scientific fields. A novel and simple procedure for the construction of tight wavelet frames generated by the Walsh polynomials using Extension Principles was recently considered by Shah in [Tight wavelet frames generated by the Walsh poly- nomials, Int. J. Wavelets, Multiresolut. Inf. Process., 11(6) (2013), 1350042]. In this paper, we establish a complete characterization of tight wavelet frames generated by the Walsh polynomials in terms of the polyphase matrices formed by the polyphase components of the Walsh polynomials. 展开更多
关键词 frame wavelet frame polyphase matrix extension principles Walsh polynomial Walsh-Fourier transform.
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基于帧间差分计算的液体滴漏自动识别系统
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作者 唐俊 袁妮 +3 位作者 赵博杨 赵锦科 赵鑫洋 张心静 《传感器与微系统》 北大核心 2025年第10期64-67,共4页
针对煤矿井下无法精准实现管道液体泄漏检测的问题,提出了基于帧间差分计算的液体滴漏自动识别方法。巡检无人车自主导航巡检井下环境,利用相机抓取视频,用YOLOv5模型定位可能发生液体泄漏的位置,再通过帧间差分法和霍夫变换法判断是否... 针对煤矿井下无法精准实现管道液体泄漏检测的问题,提出了基于帧间差分计算的液体滴漏自动识别方法。巡检无人车自主导航巡检井下环境,利用相机抓取视频,用YOLOv5模型定位可能发生液体泄漏的位置,再通过帧间差分法和霍夫变换法判断是否发生液体滴漏。若发生漏液,将标注出漏液位置并传送至软件平台,并通知煤矿人员及时处理。结果表明,该系统识别率可达98%,具有较快的识别速度,且不区分液体种类,适用于矿井下等危险区域。 展开更多
关键词 帧间差分计算 YOLOv5 霍夫变换法 液体滴漏
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Electrodynamics in Noninertial Reference Frames
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作者 Stanislav A. Podosenov Jaykov Foukzon +1 位作者 Alexander Potapov Elena Men’kova 《Journal of Applied Mathematics and Physics》 2016年第4期806-843,共38页
The electrodynamics both in RF with prescribed law of motion and in FR with prescribed structure is considered. Parallel comparison for solutions in “uniformly accelerated” NRF M?ller system and in uniformly acceler... The electrodynamics both in RF with prescribed law of motion and in FR with prescribed structure is considered. Parallel comparison for solutions in “uniformly accelerated” NRF M?ller system and in uniformly accelerated rigid NFR in the space of the constant curvature is carried out. The stationary criterion is formulated. On the basis of this criterion, one of the “eternal physical problems” concerning the field at uniformly accelerated charge motion is considered. The problems of electromagnetic wave spreading, Doppler’s effect and field transformations are discussed. 展开更多
关键词 Noninertial Reference frame (NFR) Möller System Space-Time Curvature Anholonomic transformations Doppler’s Effect Electromagnetic Wave
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利用基因编辑技术提高不结球白菜抗坏血酸的含量
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作者 王文龙 刘照坤 +7 位作者 鲁文君 王耀龙 李晓锋 朱红芳 刘同坤 李英 侯喜林 张昌伟 《园艺学报》 北大核心 2025年第5期1317-1325,共9页
为提高不结球白菜抗坏血酸含量,以不结球白菜品种‘黄玫瑰’为材料,选择不结球白菜GGP基因的uORF序列为靶标,构建CRISPR/Cas9基因组编辑载体,通过发根农杆菌介导的遗传转化方法获得了4种不同基因编辑类型‘黄玫瑰’GGP基因uORF的编辑植... 为提高不结球白菜抗坏血酸含量,以不结球白菜品种‘黄玫瑰’为材料,选择不结球白菜GGP基因的uORF序列为靶标,构建CRISPR/Cas9基因组编辑载体,通过发根农杆菌介导的遗传转化方法获得了4种不同基因编辑类型‘黄玫瑰’GGP基因uORF的编辑植株,检测再生植株的T1代纯合绿色植株的抗坏血酸含量,再与空载转基因再生植株相比,抗坏血酸含量提高了26.2%~67.1%。这为利用CRISPR/Cas9系统在不结球白菜中开展基因编辑和生物育种研究提供了依据。 展开更多
关键词 不结球白菜 上游开放阅读框 遗传转化 抗坏血酸 基因编辑
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