期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
Tensor discriminant dictionary classification method for prestack seismic reflection patterns
1
作者 Cai Han-Peng Jing Peng Yang Jun-Hui 《Applied Geophysics》 SCIE CSCD 2022年第2期197-208,307,共13页
The existing seismic reflection pattern classification methods need to convert multidimensional prestack seismic data into one-dimensional vectors for processing,which loses the characteristics of amplitude variation ... The existing seismic reflection pattern classification methods need to convert multidimensional prestack seismic data into one-dimensional vectors for processing,which loses the characteristics of amplitude variation with offset/azimuth in the prestack seismic data.In this study,a tensor discriminant dictionary learning method for classifying prestack seismic reflection patterns is proposed.The method is initially based on the tensor Tucker decomposition algorithm and uses a tensor form to characterize the prestack seismic data with multidimensional features.The tensor discriminant dictionary is then used to reduce the influence of noise on the sample features.Finally,the method uses the Pearson correlation coefficient to measure the correlation degree of the sparse representation coefficients of different types of tensors.The advantages of the new method are as follows.(1)It can retain the rich structural features in different dimensions in the prestack data.(2)It adjusts the threshold of the Pearson correlation coefficient to optimize the classification effect.(3)It fully uses drilling information and expert knowledge and performs calibration training of the sample labels.The numerical-model tests confirm that the new method is more accurate and robust than the traditional support vector machine and K-nearest neighbor classification algorithms.The application of actual data further confirms that the classification results of the new method agree with the geological patterns and are more suitable for the analysis and interpretation of sedimentary facies. 展开更多
关键词 Prestack seismic data seismic reflection pattern analysis TENSORS discriminative dictionary learning
在线阅读 下载PDF
Reflections on the Transformation of World Pattern and Resoonsibility Adjustment
2
作者 王在邦 《Contemporary International Relations》 2000年第2期1-13,共13页
The year of 2000 is at the turn of the century as well as of the millennium. Themankind waves farewell to the 20th century as well as the second millenniumand welcomes the 21st century and the third millennium. At thi... The year of 2000 is at the turn of the century as well as of the millennium. Themankind waves farewell to the 20th century as well as the second millenniumand welcomes the 21st century and the third millennium. At this special juncture,looking closely at the future based on understanding which was obtained from re-viewing and summarizing the past and present world politics from historical andphilosophical standpoints, we can find that it has become an unavoidable subject onhow to regard the trend of the world pattern toward multi-polarization and respon-sibility adjustment arising from it. 展开更多
关键词 reflections on the Transformation of World pattern and Resoonsibility Adjustment US World
在线阅读 下载PDF
Achievable Rate Analysis and Optimization of Double-RIS Assisted Spatially Correlated MIMO with Statistical CSI
3
作者 Xu Kaizhe Guo Jiajia +2 位作者 Zhang Jun Jin Shi Ma Shaodan 《China Communications》 2025年第1期139-157,共19页
Reconfigurable intelligent surface(RIS)is a novel meta-material which can form a smart radio environment by dynamically altering reflection directions of the impinging electromagnetic waves.In the prior literature,the... Reconfigurable intelligent surface(RIS)is a novel meta-material which can form a smart radio environment by dynamically altering reflection directions of the impinging electromagnetic waves.In the prior literature,the inter-RIS links which also contribute to the performance of the whole system are usually neglected when multiple RISs are deployed.In this paper we investigate a general double-RIS assisted multiple-input multiple-output(MIMO)wireless communication system under spatially correlated non line-of-sight propagation channels,where the cooperation of the double RISs is also considered.The design objective is to maximize the achievable ergodic rate based on full statistical channel state information(CSI).Specifically,we firstly present a closedform asymptotic expression for the achievable ergodic rate by utilizing replica method from statistical physics.Then a full statistical CSI-enabled optimal design is proposed which avoids high pilot training overhead compared to instantaneous CSI-enabled design.To further reduce the signal processing overhead and lower the complexity for practical realization,a common-phase scheme is proposed to design the double RISs.Simulation results show that the derived asymptotic ergodic rate is quite accurate even for small-sized antenna arrays.And the proposed optimization algorithm can achieve substantial gain at the expense of a low overhead and complexity.Furthermore,the cooperative double-RIS assisted MIMO framework is proven to achieve superior ergodic rate performance and high communication reliability under harsh propagation environment. 展开更多
关键词 common reflection pattern double RISs large system analysis MIMO replica method
在线阅读 下载PDF
A new method for specular curved surface defect inspection based on reflected pattern integrity 被引量:5
4
作者 姜美华 付鲁华 +1 位作者 王仲 宋宇航 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期221-228,共8页
Defect inspection of specular curved surface is a challenging job. Taking steel balls for example, a new method based on reflected pattern integrity recognition is put forward. The specular steel ball surfac... Defect inspection of specular curved surface is a challenging job. Taking steel balls for example, a new method based on reflected pattern integrity recognition is put forward. The specular steel ball surface will totally reflect the patterns when it is placed inside a dome-shaped light source, whose inner wall is modified by patterns with certain regular. Distortion or intermittence of reflected pattern will occur at the defective part, which indicates the pattern has lost its integrity. Based on the integrity analysis of reflected pattern images? surface defects can be revealed. In this paper, a set of concentric circles are used as the pattern and an image processing algorithm is customized to extract the surface defects. Results show that the proposed method is effective for the specular curved surface defect inspection 展开更多
关键词 specularity curved surface defect inspection reflected pattern computer vision
在线阅读 下载PDF
Reflective State Pattern with Dynamic Constructiveness
5
作者 Jiang Hong 1, He Ke\|qing 1, Ying Shi 2 1.College of Computer,Wuhan University,Wuhan 430072,China 2.State Key Laboratory of Software Engineering,Wuhan University,Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期191-199,共9页
After discussing the reflective method of structure and behavior in the State design pattern based on Role Object pattern and the Reflective pattern of software architecture, this paper proposes a reflective state pat... After discussing the reflective method of structure and behavior in the State design pattern based on Role Object pattern and the Reflective pattern of software architecture, this paper proposes a reflective state pattern with dynamic constructiveness. This paper explains the meta level and the base level, which are two levels of this pattern, and specifies the relation of two levels by using Meta Object Protocol (MOP). Then it discusses mechanism of interception and reification for reflecting base object from Meta object. Finally this paper gives an example of network server for applying the Reflective State pattern. 展开更多
关键词 role model state design pattern reflective pattern role object pattern
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部