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The braking index of PSR B0540-69 and the associated pulsar wind nebula emission after spin-down rate transition 期刊论文 OAI收割
Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 494, 页码: 1865-1870
作者: HXMT

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收藏 | 浏览/下载：71/0 | 提交时间：2022/02/08

stars: magnetic field stars: neutron pulsars: general Astrophysics - High Energy Astrophysical Phenomena Abstract: In 2011 December, PSR B054-69 experienced a spin-down rate transition (SRT), after which the spin-down power of the pulsar increased by $\sim 36{{\ \rm per\ cent}}$. About 1000 d after the SRT, the X-ray luminosity of the associated pulsar wind nebula (PWN) was found to brighten by $32\pm 8{{\ \rm per\ cent}}$. After the SRT, the braking index n of PSR B0540-69 changes from n = 2.12 to 0.03 and then keeps this value for about five years before rising to n = 0.9 in the following years. We find that most of the current models have difficulties in explaining the measured braking index. One exceptive model of the braking index evolution is the increasing dipole magnetic field of PSR B0540-69. We suggest that the field increase may result from some instabilities within the pulsar core that enhance the poloidal component at the price of toroidal component of the magnetic field. The increasing dipole magnetic field will result in the X-ray brightening of the PWN. We fit the PWN X-ray light curve by two models: one assumes a constant magnetic field within the PWN during the brightening and the other assumes an enhanced magnetic field proportional to the energy density of the PWN. It appears that the two models fit the data well, though the later model seems to fit the data a bit better. This provides marginal observational evidence that magnetic field in the PWN is generated by the termination shock. Future high-quality and high-cadence data are required to draw a solid conclusion.

Multi-Pseudo Regularized Label for Generated Data in Person Re-Identification 期刊论文 OAI收割
IEEE TRANSACTIONS ON IMAGE PROCESSING, 2019, 卷号: 28, 期号: 3, 页码: 1391-1403
作者: Huang, Yan; Xu, Jingsong; Wu, Qiang; Zheng, Zhedong; Zhang, Zhaoxiang

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收藏 | 浏览/下载：84/0 | 提交时间：2019/07/12

Person re-identification generated data virtual label semi-supervised learning

Research of software re-injection technology for aerospace camera controller in-orbit (EI CONFERENCE) 会议论文 OAI收割
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
Xu W.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

For the factors of increased of tasks enhancements of functions and improvement of integrity and complexity in aerospace camera application system has raised high and long-term in-orbit autonomy and reliability requirements on camera controller. Based on an actual project application background this paper has put forward a design method of new high reliability aerospace camera controller in-orbit software reinjection instruction sequence which use TSC695F as kernel CPU and process flow of bootstrap receive cache checkout and storage update data. Finally combined with specific test module for camera controller software re-injection the validity of the software re-injection method raised here has been verified. Still here gives out reference codes of update data package which generated by the ground. 2012 IEEE.

Physical layer design for free space optical communication (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 H.; Zhang Q.

收藏 | 浏览/下载：38/0 | 提交时间：2013/03/25

A small size Free Space Optical Communication System is introduced including the hardware and the hardware specified physical layer protocol. In detail the rapid synchronization method to reduce the handshake bandwidth requirement is demonstrated. The hardware of the system includes the laser driver system the signal amplifying and shaping system the data interface system. The hardware specified physical layer protocol is used to interface the outer data serialize and deserialize the data stream check transmission errors and schedule the data transmission. The overall system is a FIFO-like system and the user can use it as if he's operating a FIFO. The system is designed mainly for terrestrial FSO link whose signal channel is the atmosphere. Due to the complex composition and activity of the atmosphere this signal channel brings in great influence on the transmitting laser in it for example the absorption and scattering of the atmosphere molecules and aerosols the scintillation of received laser power caused by the turbulence of the atmosphere all of which results in a much higher Bit Error Rate (BER) of the communication system than wired communication systems leading to frequent resynchronization. In our system the sampling clock is generated locally using multi-phase sampling technique rather than PLLbased clock recovery which helps to rapid synchronization. 2012 IEEE.

Geocentric distance's errors' correction of space cameras based on USGS DEM (EI CONFERENCE) 会议论文 OAI收割
2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011, May 27, 2011 - May 29, 2011, Xi'an, China
作者: Li W.; Li W.; Xu S.

收藏 | 浏览/下载：35/0 | 提交时间：2013/03/25

In order to correct the geocentric distance's error of TDI (Time Delay and Integration) CCD space camera in calculation of image motion compensation the data source of the earth's height above sea level USGS DEM (United States Geological Survey Digital Elevation Model) has been introduced to make digital elevation map the match error of the forward direction (the integral direction of TDI CCD) has been greatly decreased by correcting the geocentric distance error and eliminate the influence to the relative error of image motion velocity and correct the error generated by the different heights above sea level. After correcting which greatly improves the imaging quality of TDI CCD space camera. 2011 IEEE. a model of image motion calculation of nadir has been introduced the calculation and analysis of the model shows that: the maximum error of image motion velocity about 1.72% has been decreased to 0.06% and the influence of the geocentric distance error to the relative error of image motion velocity has been analyzed with the model

The research of electromachanical actuator control system development based on the MATLAB platform using the RTDX (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者: Zhang J.; Zhang Y.; Zhang J.; Zhang J.

收藏 | 浏览/下载：48/0 | 提交时间：2013/03/25

In order to rapidly develop the control system code of the Electromachanical Actuator(EMA) the DSP development platform is established mostly based on the MATLAB and the development metheod is researched.First the DSP development platform archtecture in the environment of MATLAB is briefly introduced.And the principle of data exchange is showed.Then the EMA hardware structure is necessarily explained which one is for the developer to conveniently configure the system.Finally the developer reasonably configures the DSP models used in the simulink and constitutes them to speed and position closed loop control system of the EMA by using the RTDX and the MATLAB GUI. The EMA control system code will be debuged rapidly through this platform.The executed DSP code will be generated automatically.And the result of degugging would be showed on the MATLAB GUI.For generlly speaking the difficulties of the EMA control system code development method is reduced and the development cycle is shortened through the MATLAB model.This system development method is fast and effective. 2011 IEEE.

Citizen-generated spatial data and information: Risks and opportunities 会议论文 OAI收割
2011 IEEE International Conference on Intelligence and Security Informatics, ISI 2011,, Beijing, China, July 10, 2011 - July 12,2011
Mooney, Peter; Sun, Huabo; Corcoran, Padraig; Yan, Lei

收藏 | 浏览/下载：28/0 | 提交时间：2014/12/07

The use of location-enabled mobile technology is ubiquituos. We outline the opportunities and risks involved in using user-generated spatial data and information. User generated spatial data is a very dynamic but has many inconsistencies. This could severely limit its use in many security and intelligence applications. 2011 IEEE.

A local feature based simplification method for animated mesh sequence (EI CONFERENCE) 会议论文 OAI收割
2010 2nd International Conference on Computer Engineering and Technology, ICCET 2010, April 16, 2010 - April 18, 2010, Chengdu, China
作者: Wang B.; Wang B.; Zhao J.; Zhang S.

收藏 | 浏览/下载：35/0 | 提交时间：2013/03/25

Although animated meshes are frequently used in numerous domains only few works have been proposed until now for simplifying such data. In this paper we propose a new method for generating progressive animated models based on local feature analysis and deformation area preservation. We propose the use of solid angle and height value for a non-hyperbolic vertex to define the local feature parameter. This local factor is embedded to the vertex quadric error matrix when calculating the edge collapse cost. In order to preserve the areas with large deformation we add deformation degree weight to the aggregated quadric errors when computing the unified edge contraction sequence. Finally a mesh optimization process is proposed to further reduce the geometric distortion for each frame. Our approach is fast easy to implement and as a result good quality dynamic approximations with well-preserved fine details can be generated at any given frame. 2010 IEEE.

Inhibition of electromagnetic interference in control system based on DSP of high-power TEA CO2 laser (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
作者: Meng F.-J.; Guo L.-H.; Wang H.-Q.

收藏 | 浏览/下载：47/0 | 提交时间：2013/03/25

The strong electromagnetic interference (EMI) generated in high-power TEA C02 laser system mainly comes from main discharge circuit pulse spark switch and power supply. Such strong EMI causes great damage and interference to the control system based on DSP. In this paper we present the interference sources and their distribution and propose the methods of anti-interference. Measures for hardware design include weakening transient ground potential difference by using equipotential lines between devices using signal isolation interface to inhibit the transient ground potential interference and rational layout shielding and filtering to the control system. And methods for software design include range-limited filter self-diagnosis and self-repair for the critical data and anti-interference during abnormal reset. The EMI has been inhibited effectively by the anti-interference method proposed above. The result shows that: the software anti-interference method is as important as the hardware anti-interference method for the control system in a complex environment of strong EMI. 2010 IEEE.

Research on software defect prediction based on data mining (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Computer and Automation Engineering, ICCAE 2010, February 26, 2010 - February 28, 2010, Singapore, Singapore
作者: Chen Y.

收藏 | 浏览/下载：45/0 | 提交时间：2013/03/25

As the development of computer technology software system becomes more and more complicated. Because of human's ability limit there must be a lot of defects generated in the software development life cycle. This paper reviewed the state of art in the field of software defect management and prediction and presented data mining technology briefly. Finally proposed an ideal software defect management and prediction system researched and analyzed several software defect prediction methods based on data mining techniques and specific models (Bayesian Network and PRM). With this system we can efficiently draw up some prevention and solution scheme to guide the development of new software. 2010 IEEE.