A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous ...A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous underwater vehicle(PDAUV) is hereby designed to solve these problems when working with advanced optical,acoustical and electrical sensors for underwater pipeline detection.PDAUV is a test bed that not only examines the logical rationality of the program,effectiveness of the hardware architecture,accuracy of the software interface protocol as well as the reliability and stability of the control system but also verifies the effectiveness of the control system in tank experiments and sea trials.The motion control system of PDAUV,including both the hardware and software architectures,is introduced in this work.The software module and information flow of the motion control system of PDAUV and a novel neural network-based control(NNC) are also covered.Besides,a real-time identification method based on neural network is used to realize system identification.The tank experiments and sea trials are carried out to verify the feasibility and capability of PDAUV control system to complete underwater pipeline detection task.展开更多
词性是自然语言处理的基本要素,词语顺序包含了所传达的语义与语法信息,它们都是自然语言中的关键信息.在word embedding模型中如何有效地将两者结合起来,是目前研究的重点.本文提出的Structured word2vec on POS联合了词语顺序与词性...词性是自然语言处理的基本要素,词语顺序包含了所传达的语义与语法信息,它们都是自然语言中的关键信息.在word embedding模型中如何有效地将两者结合起来,是目前研究的重点.本文提出的Structured word2vec on POS联合了词语顺序与词性两种信息,不仅使模型可以感知词语位置顺序,而且利用词性关联信息来建立上下文窗口内词语之间的固有句法关系.Structured word2vec on POS将词语按其位置顺序定向嵌入,对词向量和词性相关加权矩阵进行联合优化.实验通过词语类比、词相似性任务,证明了所提出的方法的有效性.展开更多
介绍了INS/DR/MM车辆组合导航系统以及系统的部件组成,对系统的软硬件结构进行了分析。结合目前各主流嵌入式平台的性能,利用Windows XP Embedded(XPE)嵌入式操作系统体积小和易扩展的优势,选用Windows XP Embedded作为车辆组合导航系...介绍了INS/DR/MM车辆组合导航系统以及系统的部件组成,对系统的软硬件结构进行了分析。结合目前各主流嵌入式平台的性能,利用Windows XP Embedded(XPE)嵌入式操作系统体积小和易扩展的优势,选用Windows XP Embedded作为车辆组合导航系统的开发平台。为了满足车辆导航实时、快速的要求,设计了基于模糊逻辑的地图匹配算法。经过多次实际跑车试验证明,该嵌入式车辆导航系统可以正确实时地将地图匹配后的位置信息显示在电子地图上。展开更多
超光谱图像作为一种三维图像,其海量的数据导致在有限带宽信道上传输和存储非常困难,必须对它进行有效的压缩编码.提出了一种基于非对称三维小波变换(3D wavelet transform,简称3DWT)和三维集合块分裂的超光谱遥感图像压缩方法.因为大...超光谱图像作为一种三维图像,其海量的数据导致在有限带宽信道上传输和存储非常困难,必须对它进行有效的压缩编码.提出了一种基于非对称三维小波变换(3D wavelet transform,简称3DWT)和三维集合块分裂的超光谱遥感图像压缩方法.因为大多数超光谱图像在各个方向上具有非对称的统计特性,所以利用非对称三维小波变换去除图像的谱间和空间冗余.与传统的对称三维小波变换相比,非对称的三维小波变换能够更有效地去除相邻谱段间的冗余.提出了一种改进的3DSPECK(3D set partitioning embedded block)算法——非对称三维集合分裂块算法(asymmetric transform 3DSPECK,简称AT-3DSPECK),并被用于编码变换后的系数.根据变换系数的能量分布特点,三维零块分裂和三维octave子带分裂方法被有效地结合在所提出的AT-3DSPECK算法中.为了优化率失真和加速编码速度,也给出了一种零块优化排序的快速算法.实验测试表明:AT-3DSPECK算法的平均PSNR(peak signal to noise ratio)分别比AT-3DSPIHT(asymmetric transform 3D set partitioning in hierarchical trees)和3DSPECK算法高0.4dB和1.4dB.此外,AT-3DSPECK还具有比零树算法更快的编码速度.展开更多
基金Project(2011AA09A106)supported by the Hi-tech Research and Development Program of ChinaProject(51179035)supported by the National Natural Science Foundation of ChinaProject(2015ZX01041101)supported by Major National Science and Technology of China
文摘A great number of pipelines in China are in unsatisfactory condition and faced with problems of corrosion and cracking,but there are very few approaches for underwater pipeline detection.Pipeline detection autonomous underwater vehicle(PDAUV) is hereby designed to solve these problems when working with advanced optical,acoustical and electrical sensors for underwater pipeline detection.PDAUV is a test bed that not only examines the logical rationality of the program,effectiveness of the hardware architecture,accuracy of the software interface protocol as well as the reliability and stability of the control system but also verifies the effectiveness of the control system in tank experiments and sea trials.The motion control system of PDAUV,including both the hardware and software architectures,is introduced in this work.The software module and information flow of the motion control system of PDAUV and a novel neural network-based control(NNC) are also covered.Besides,a real-time identification method based on neural network is used to realize system identification.The tank experiments and sea trials are carried out to verify the feasibility and capability of PDAUV control system to complete underwater pipeline detection task.
文摘词性是自然语言处理的基本要素,词语顺序包含了所传达的语义与语法信息,它们都是自然语言中的关键信息.在word embedding模型中如何有效地将两者结合起来,是目前研究的重点.本文提出的Structured word2vec on POS联合了词语顺序与词性两种信息,不仅使模型可以感知词语位置顺序,而且利用词性关联信息来建立上下文窗口内词语之间的固有句法关系.Structured word2vec on POS将词语按其位置顺序定向嵌入,对词向量和词性相关加权矩阵进行联合优化.实验通过词语类比、词相似性任务,证明了所提出的方法的有效性.
文摘介绍了INS/DR/MM车辆组合导航系统以及系统的部件组成,对系统的软硬件结构进行了分析。结合目前各主流嵌入式平台的性能,利用Windows XP Embedded(XPE)嵌入式操作系统体积小和易扩展的优势,选用Windows XP Embedded作为车辆组合导航系统的开发平台。为了满足车辆导航实时、快速的要求,设计了基于模糊逻辑的地图匹配算法。经过多次实际跑车试验证明,该嵌入式车辆导航系统可以正确实时地将地图匹配后的位置信息显示在电子地图上。
文摘超光谱图像作为一种三维图像,其海量的数据导致在有限带宽信道上传输和存储非常困难,必须对它进行有效的压缩编码.提出了一种基于非对称三维小波变换(3D wavelet transform,简称3DWT)和三维集合块分裂的超光谱遥感图像压缩方法.因为大多数超光谱图像在各个方向上具有非对称的统计特性,所以利用非对称三维小波变换去除图像的谱间和空间冗余.与传统的对称三维小波变换相比,非对称的三维小波变换能够更有效地去除相邻谱段间的冗余.提出了一种改进的3DSPECK(3D set partitioning embedded block)算法——非对称三维集合分裂块算法(asymmetric transform 3DSPECK,简称AT-3DSPECK),并被用于编码变换后的系数.根据变换系数的能量分布特点,三维零块分裂和三维octave子带分裂方法被有效地结合在所提出的AT-3DSPECK算法中.为了优化率失真和加速编码速度,也给出了一种零块优化排序的快速算法.实验测试表明:AT-3DSPECK算法的平均PSNR(peak signal to noise ratio)分别比AT-3DSPIHT(asymmetric transform 3D set partitioning in hierarchical trees)和3DSPECK算法高0.4dB和1.4dB.此外,AT-3DSPECK还具有比零树算法更快的编码速度.
