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Neural Encoding for Human Visual Cortex With Deep Neural Networks Learning "What" and "Where" 期刊论文  OAI收割
IEEE TRANSACTIONS ON COGNITIVE AND DEVELOPMENTAL SYSTEMS, 2021, 卷号: 13, 期号: 4, 页码: 827-840
作者:  
Wang, Haibao;  Huang, Lijie;  Du, Changde;  Li, Dan;  Wang, Bo
  |  收藏  |  浏览/下载:31/0  |  提交时间:2022/01/27
An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242 期刊论文  OAI收割
Astronomy and Astrophysics, 2020, 卷号: 641, 页码: A101
作者:  
HXMT
  |  收藏  |  浏览/下载:58/0  |  提交时间:2022/02/08
accretion  accretion disks  black hole physics  X-rays: binaries  time  Astrophysics - High Energy Astrophysical Phenomena  Abstract:
Aims: Flip-flops are top-hat-like X-ray flux variations, which have been observed in some transient accreting black hole binary systems, and feature simultaneous changes in the spectral hardness and the power density spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disc emission starts to dominate over coronal emission. Flip-flops remain a poorly understood phenomenon, so we aim to thoroughly investigate them in a system featuring several such transitions.
Methods: Within the multitude of observations of Swift J1658.2-4242 during its outburst in early 2018, we detected 15 flip-flops, enabling a detailed analysis of their individual properties and the differences between them. We present observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analysed their light curves, searched for periodicities, computed their PDSs, and fitted their X-ray spectra, to investigate the source behaviour during flip-flop transitions and how the interval featuring flip-flops differs from the rest of the outburst.
Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within 100 s, which is much larger than what has been seen previously. We observed radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the quasi-periodic oscillation types C and A, which have never been observed before. Changes in the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals within the outburst, separated by about two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period of 2.761 ks in the first interval and 2.61 ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be very similar, but distinct from intervals lacking flip-flops. A change of the inner temperature of the accretion disc is responsible for most of the flux difference in the flip-flops. We also highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.
  
Communication synchronization in wireless optical link (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者:  
Guo J.;  Guo J.;  Wang H.;  Wang H.;  Wang H.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
An FPGA based transceiving synchronization method is demonstrated for Free Space Optical (FSO) communication system  which is discussed separately as the transmitting protocol and the receiving protocol. During the discussion of these two parts  the co-operation of them is also discussed. The transmitting protocol interfaces the outer input data with a parallel port  buffers the input data  encodes the input data stream  serializes the parallel data and outputs the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The receiving protocol filters and synchronizes the input serial data stream  parallels the serial data stream  decodes the input data  checks received error  handles transmission exception and interfaces the outer receiver with a parallel port. The entire transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. The presented protocol could be taken as "protocol transparent" for outer interfaces  meaning that when interfacing the presented system to an outer system  users don't have to consider what protocol the outer system transceiving data stream is under  for example  the TCP/IP protocol or anything else  in the case that its I/O interface is a parallel port. Simulation and final experiment prove that the protocol presented is a working solution at a certain bit rate scale. 2012 IEEE.  
The design and implementation of temperature acquisition system based on PXI (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者:  
Wang J.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
What happens beyond Drucker's proposition when damage occurs-continuous bifurcation, damage localization and catastrophic rupture 会议论文  OAI收割
23rd International Congress of Theoretical and Applied Mechanics, 中国北京/Beijing, China, 2012-08-19
作者:  
Bai YL(白以龙);  Ma GW(马广闻);  Hao SW(郝圣旺);  Xia MF(夏蒙棼);  Ke FJ(柯孚久)
收藏  |  浏览/下载:21/0  |  提交时间:2014/04/02
Image forward motion compensation method for some aerial reconnaissance camera based on neural network predictive control (EI CONFERENCE) 会议论文  OAI收割
International Conference on Advanced Research on Computer Science and Information Engineering, CSIE 2011, May 21, 2011 - May 22, 2011, Zhengzhou, China
Zhong C.; Ding Y.; Fu J.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
The lightweight design of the inner framework of the opto-electronic stabilization platform based on finite element analysis (EI CONFERENCE) 会议论文  OAI收割
2011 IEEE 18th International Conference on Industrial Engineering and Engineering Management, IE and EM 2011, September 3, 2011 - September 5, 2011, Changchun, China
Zou Q.; Ma H.-L.; Hu Y.; Ding J.-W.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
The airborne opto-electronic stabilization platform should have the characteristics of high requirements for stability  tracking accuracy and lightweight. In order to verify the rationality of the main load-bearing structure  the inner-gimbal  finite element analysis was performed. Because of the poor working conditions of the airborne opto-electronic stabilization platform and the wide range of working temperature variation  -45 C 60 C  according to the actual working environment  air-resistance and temperature were added to the loads of the inner-gimbal in analysis. What's more  based on the analysis results  lightweight design was performed to the initial model and 64.37% of mass was decreased. The remarkable effect was obtained. This research is going to be instructive to design and production of the airborne opto-electronic stabilization platform in the future. 2011 IEEE.  
Computer simulation research on cognitive mechanism of human vision (EI CONFERENCE) 会议论文  OAI收割
International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2010, March 13, 2010 - March 14, 2010, Changsha, China
Ke H.; You W.
收藏  |  浏览/下载:37/0  |  提交时间:2013/03/25
The development of intelligent system which accorded with human cognitive mechanism will exert a profound influence on national defense  economy  education  culture and etc. A computer simulation method according with cognitive mechanism of human vision was proposed on the basis of Structural Decomposition Theory. Many basic shape feature information tables of similar object from different side can determine a kind of object uniquely. System weighted basic shape features in two different information tables by membership degree and then calculated similarity. The identifying object which had the maximum similarity with it in system was what we needed. The system used 83 pictures of 6 kinds of objects with different side for training and testing. The experiment results demonstrated  task of basic shape extraction  object recognition and others can be completed effectively with the method in paper. The method in paper can be a new attempt on computer simulation method according with cognitive mechanism of human vision from cognitive field. 2010 Crown Copyright.  
Research on the the device of non-angular vibration for opto-electronic platform (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing, April 26, 2010 - April 29, 2010, Dalian, China
An Y.; Song C.-P.; Kuang R.-J.; Jin G.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
The opto-electronic platform is the main equipment for aviation reconnaissance. It is a surveillance system with the function of search  recognition orientation and tracking by opto- electronic instruments. It is made up of opto-electronic instruments which are used to get high quality image  and stabilization tracking system to control stabilization and gesture of platform for exact tracking. The opto-electronic platform purpose is to achieve high quality image. Besides the impact of optic system  the image quality of the system is influenced greatly in the vibration environment. The research worked by Zhao peng which demonstrated the affection caused by angular vibration was worse than which caused by line vibration  and what was multiplied direct ratio with plane altitude. So it is necessary to design a new device which could be used widely and has good angular vibration isolation effect. According to the theory of parallelogram  the non-angular vibration device had been designed with spatial links  and the theory of non-angular vibration was analyzed. The three-dimensional model was set with UG  the analysis was done by ADAMS/vibration software. The acceleration and displacement response of the device in each direction was calculated by inspiriting it with sine wave of the acceleration in three directions  and the stiffness and damp were studied. All the work prove the design principle of the device is reasonable  and the device is adopted to keep the platform motion moving horizontally  at the meantime the device is good at isolating vibration in all directions. 2010 SPIE.  
White-light spectral scanning interferometry for surface measurement system (EI CONFERENCE) 会议论文  OAI收割
6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China
作者:  
Wang C.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
The paper introduces the white-light spectral scanning interferometry for surface measurement. This interferometry can be used to measure the roughness of both smooth surfaces and those with large step heights. This real-time surface measurement can be achieved using acousto-optic tuneable filtering (AOTF) technique without mechanical scanning. At first  the structure and principle of this interferometry is introduced. Then the algorithm of the surface roughness measurement is proposed. What's more  the experiment with standard test piece is conducted. Compared with the traditional laser-light interferometry  the data shows that the proposed method has a higher accuracy which is proved to be nano-scale. A conclusion is given at last in which the superiorities and the limitations of the proposed system were discussed. 2010 SPIE.