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Generalizing hierarchical and variation partitioning in multiple regression and canonical analyses using the rdacca.hp R package 期刊论文 OAI收割
METHODS IN ECOLOGY AND EVOLUTION, 2022, 卷号: 13, 期号: 4, 页码: 782-788
作者: Lai, Jiangshan; Zou, Yi; Zhang, Jinlong; Peres-Neto, Pedro R.

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收藏 | 浏览/下载：10/0 | 提交时间：2024/03/07

averaging over orderings CCA commonality analysis constrained ordination db-RDA explained variation RDA relative importance

Synchronous X-ray/Optical QPOs from the Black Hole LMXB MAXI J1820+070 期刊论文 OAI收割
Monthly Notices of the Royal Astronomical Society, 2021
作者: HXMT

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收藏 | 浏览/下载：53/0 | 提交时间：2022/02/08

black hole physics Low Mass X-ray Binaries accretion accretion discs stars: individual (MAXI J1820+070) Astrophysics - High Energy Astrophysical Phenomena Abstract: We present high-speed optical photometry from SAAO and SALT on the black hole LMXB MAXI J1820+070 (ASSASN-18ey), some of it simultaneous with NICER, Swift and Insight-HXMT X-ray coverage. We detect optical Quasi-Periodic Oscillations (QPOs) that move to higher frequencies as the outburst progresses, tracking both the frequency and evolution of similar X-ray QPOs previously reported. Correlated X-ray/optical data reveal a complex pattern of lags, including an anti-correlation and a sub-second lag that evolve over the first few weeks of outburst. They also show correlated components separated by a lag equal to the QPO period roughly centered on zero lag, implying that the inter-band variability is strongly and consistently affected by these QPOs at a constant phase lag of roughly ±Ю The synchronisation of X-ray and optical QPOs indicates that they must be produced in regions physically very close to each other we thus propose that they can be explained by a precessing jet model, based on analogies with V404 Cyg and MAXI J1348-630.

The measuring method for low rotational speed with the frequency difference generated by radial gratings (EI CONFERENCE) 会议论文 OAI收割
2012 International Applied Mechanics, Mechatronics Automation Symposium, IAMMAS 2012, September 7, 2012 - September 9, 2012, Shenyang, Liaoning, China
Guo W.-l.; Qiao Y.-f.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

The new method has been proposed based on the comparison and analysis of the traditional methods for measuring rotating speed. It can guarantee real-time property with radial gratings at measuring low speed. It is clearly explained that the fundamental principle for measuring rotating speed and characters of the method and presented the constitution of the system hardware and the process flows. (2012) Trans Tech Publications Switzerland.

Plant communities and factors responsible for vegetation pattern in an alpine area of the northwestern Himalaya 期刊论文 OAI收割
JOURNAL OF MOUNTAIN SCIENCE, 2011, 卷号: 8, 期号: 6, 页码: 817–826
Rana, Man S.; Samant, S. S.; Rawat, Y. S.

收藏 | 浏览/下载：42/0 | 提交时间：2013/08/12

Species diversity Indicator species Environmental variable Ordination Explained variation

SGCMG design and time accumulation error analysis (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
Xu W.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

SGCMG receives much concern due to the performance of its excellent torque output on spacecraft control it has been applied to large foreign spacecraft already but late start and only limited to configurations and steering law study in China. Based on the needs of agility small satellites this article explained the method of SGCMG principle prototype design and proposed the influence on SGCMG output torque precision generated by time accumulation error first time. This article provided a new idea for future SGCMG project development and had good reference value for SGCMG research. 2011 IEEE.

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：43/0 | 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.

Nonlinear analysis method for predicting optical surface deformations resulted from assembly process (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
Dong W.; Yong Y.; Guang J.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

There are three main nonlinear elements in the large mirror assemblies which are screw pretension adhesive stress and state changes in the assembly process. The optical shape will be influenced seriously by these factors. But the impacts will not be shown in linear analysis results because as the simplification these factors have been ignored. The nonlinear analysis method for predicting optical surface deformations resulted from assembly process is discussed in detail. Take a typical mirror support structure for example the nonlinear analysis model was established. Comparing the calculation results with the optical shape test it is illustrated that nonlinear analysis is more accurate and closer to the test result. And according to the simulation result the bowl-shaped depression which was discovered in the test can also be explained reasonably. 2010 Copyright SPIE - The International Society for Optical Engineering.

An information theoretic approach to model reduction based on frequency-domain Cross-Gramian information (EI CONFERENCE) 会议论文 OAI收割
2010 8th World Congress on Intelligent Control and Automation, WCICA 2010, July 7, 2010 - July 9, 2010, Jinan, China
作者: Zhou J.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

We focused our attention on model reduction for linear time invariant (LTI) continuous time systems with single input and single output (SISO). We analyzed the strongpoint and shortcoming of an information theoretic approach called minimum information loss method for model reduction. We explained relationships between the steady-state information entropy and controllability information for the Gaussian systems. The controllability observability and Cross-Gramian information were analyzed in the time-domain. The frequency-domain Cross-Gramian information (FCGI) was defined based on Cross-Gramian matrix containing information associated with both controllability and observability. Furthermore a valuable application of the frequency-domain Cross-Gramian information to model reduction (FCGMIL) was developed by using the concept and properties of frequency-domain Cross-Gramian information. The performance index of FCGMIL is to minimize the frequency-domain Cross-Gramian information loss caused by eliminating the state variables with weak contributions to Cross-Gramian information over some frequency band. Two numerical examples are illustrated to verify the efficiency of FCGMIL. 2010 IEEE.

Research on the airborne communication and navigation apparatus ATE system based on the virtual instrument (EI CONFERENCE) 会议论文 OAI收割
2008 Pacific-Asia Workshop on Computational Intelligence and Industrial Application, PACIIA 2008, December 19, 2008 - December 20, 2008, Wuhan, China
Zijing Z.; Zhongbao X.; Yanbin S.

收藏 | 浏览/下载：74/0 | 提交时间：2013/03/25

The airborne communication and navigation (CN) apparatus ATE system is the important apparatus for measure the working state and performance of the CN automatically and quickly. It has explained the composition of the ATE system based on the virtual instrument the bus structure and signal recuperated in this paper. The ATE System adopts platformization fault diagnosis thought the fault diagnose mechanism and logic are designed by the users which is an organic whole realized the fault diagnoses and the maintain means coordination. System is interchangeable and upgradeable on operating system special-purpose tester and the testing program is portable between the different ATE. Indicate by the practice the airborne CN apparatus ATE system have good military and economic benefits. 2008 IEEE.

Novel algorithm for computer-aided alignment of wide field of view complex optical system (EI CONFERENCE) 会议论文 OAI收割
Yang X.; Han C.

收藏 | 浏览/下载：32/0 | 提交时间：2013/03/25

With the advent of the new complex optical system alignment technology is necessary. In this paper is presented an alignment algorithm whose main idea is composed of damped least square method and singular value decomposition method. In addition the how and why to enter the damped factor into algorithm is explained. According to this algorithm an alignment software package was compiled and compared self-compiled software with alignment package of CODE V. Results show that this self-compiled software is much more valid than alignment package of CODE V. For a field of view of 2 R-C system average MTF over the field of view was greater than 0.3 at 50 line pairs /mm.