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An Optimized Transformation System and Functional Test of CYC-Like TCP Gene CpCYC in Chirita pumila (Gesneriaceae) 期刊论文  OAI收割
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, 2021, 卷号: 22, 期号: 9
作者:  
Liu, Jing;  Wang, Juan-Juan;  Wu, Jie;  Wang, Yang;  Liu, Qi
  |  收藏  |  浏览/下载:15/0  |  提交时间:2023/02/24
A New Set of Parameters of High-Mass X-ray Binaries Found with their Cyclotron Lines 期刊论文  OAI收割
arXiv e-prints, 2018
作者:  
Zhang, Chengmin;  Taani, Ali;  Chaty, Sylvain;  Karino, Shigeyuki;  Song, Liming
  |  收藏  |  浏览/下载:76/0  |  提交时间:2019/07/12
Astrophysics - High Energy Astrophysical Phenomena  Abstract: We have derived new physical quantities for several High-Mass X-ray Binaries (HMXBs) with supergiant (SG) companions through their cyclotron lines. The parameters are: the terminal velocity of the wind, the mass loss rate of the donor, the effective temperature and the magnetic fields. These parameters influence significantly the improvement of the model of accretion. In spite of the variety of their observational properties, the corresponding magnetic field is around B ~ 10^12 G. This result can be constrained by the effects on stellar evolution. In addition, we have performed a segmentation in the parameter space of donors intended for several SG-HMXB listed in our sample set. The parameter space can be categorized into five regimes depending on the possibility of disk formation associated with accretion from the stellar wind. This can give a quantitative clarification of the observed variability and the properties of these objects. We show that, when these systems come into the direct accretion region, systems with corresponding parameters can emit X-rays.  
Effect of Zn doping on the hydrogenolysis of glycerol over ZnNiAl catalyst 期刊论文  OAI收割
journal of molecular catalysis a-chemical, 2014, 卷号: 395, 页码: 1-6
Li, Xiaoru; Zhang, Chao; Cheng, Haiyang; He,Limin; Lin,Weiwei; Yu,Yancun; Zhao,Fengyu
收藏  |  浏览/下载:87/0  |  提交时间:2015/10/20
Nickel based catalyst is of interest in the industrial catalytic processes  and it is always modified by doping a second element to improve its catalytic properties. Understanding the role of dopant is extremely helpful in tailoring the active centers. In this work  Zn could induce a significant improvement of the catalytic performance of NiAl for the hydrogenolysis of glycerol. The Zn doped ZnNiAl catalysts exhibited high activity and the improved selectivity to 1  2-propanediol  it was about 2 times higher than the original ones. The ZnNi alloy formed in ZnNiAl was responsible for the noticeable catalytic performance. They preferred to coordinate with the end hydroxyl group of glycerol  promoted the cleavage of C-O bond in glycerol  and resulted in the dominant formation of 1  2-propanediol. The findings described here will provide a useful knowledge for rational design of nickel-based catalysts  as well as reveal a new reaction model for the hydrogenolysis of glycerol. (C) 2014 Elsevier B.V. All rights reserved.  
A sub-pixel extraction method for the center of the circular structure from spot array calibration target (EI CONFERENCE) 会议论文  OAI收割
2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China
作者:  
Liu Y.;  Zhang T.;  Yang H.;  Gao X.;  Liu Y.
收藏  |  浏览/下载:75/0  |  提交时间:2013/03/25
Image matching using a bat algorithm with mutation (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Mechatronic Systems and Automation Systems, MSAS 2012, July 21, 2012 - July 21, 2012, Wuhan, China
作者:  
Zhang J.;  Wang G.;  Zhang J.;  Zhang J.
收藏  |  浏览/下载:40/0  |  提交时间:2013/03/25
Due to shortcoming of traditional image matching for computing the fitness for every pixel in the searching space  a new bat algorithm with mutation (BAM) is proposed to solve image matching problem  and a modification is applied to mutate between bats during the process of the new solutions updating. This new approach can accelerate the global convergence speed while preserving the strong robustness of the basic BA. The realization procedure for this improved meta-heuristic approach BAM is also presented. To prove the performance of this proposed meta-heuristic method  BAM is compared with BA and other population-based optimization methods  DE and SGA. The experiment shows that the proposed approach is more effective and feasible in image matching than the other model. (2012) Trans Tech Publications  Switzerland.  
Modeling and variable structure control of a vehicle flexible manipulator (EI CONFERENCE) 会议论文  OAI收割
10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China
作者:  
Wang Z.;  Li Y.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
In this paper  the mathematical modeling and the application of a new trajectory tracking control technique for hydraulic-driven rigid-flexible manipulator are concerned. To get a closer dynamic behavior of the real system  both the flexible manipulator linkage and the actuator dynamics are considered. The exact dynamic model of flexible manipulator is derived using Lagrange principle and assumed modes method. The partial decoupled dynamic equation is derived using nonlinear decoupling feedback control method. The whole dynamic model is established by a driven Jacobin matrix  which represents the coupling between hydraulic servo system and mechanical system. A variable structure controller with inverse dynamics is designed for trajectory tracking. To weaken the chattering of control signal  saturation function is used to instead of sign function. The experimental results investigate the effectiveness of the proposed approaches. 2012 IEEE.  
Systemic model for software cost analyzing and optimizing (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:  
Zhanglei;  Zhanglei
收藏  |  浏览/下载:60/0  |  提交时间:2013/03/25
Reentry guidance based on feedback linearization (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronics, Communications and Control, ICECC 2011, September 9, 2011 - September 11, 2011, Ningbo, China
Li D.-W.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
This paper presents a new reentry guidance algorithm for RLV (Reusable Launching Vehicle). The algorithm consists of two integrated components: trajectory planning algorithm and tracking algorithm. The most striking feature of algorithm here lies in that both planning and tracking are executed directly in height-velocity space  which is different from the methodology of configuration of drag in traditional shuttle guidance. In the session of trajectory planning  all trajectory constraints can be expressed with upper bound and lower bound in height-velocity space  then a linear interpolation is carried to search the nominal trajectory satisfying the requirement of downrange and target constraints. Then the tracking algorithm uses feedback linearization method to track this nominal profile and meet all constraints. Another typical feature of this algorithm is the strategy of downrange extension using FPA (flight path angle) controller to fulfill the requirement of large downrange. Proper combination of planning-tracking algorithm and FPA controller can bring great flexibility and adaptability to reentry guidance. The algorithm is proved to be robust enough to accommodate the model error and noises in the dynamics. 2011 IEEE.  
Design of motion adjusting system for space camera based on ultrasonic motor (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
作者:  
Sun Z.
收藏  |  浏览/下载:85/0  |  提交时间:2013/03/25
Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper  some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system  which is composed of the drift adjusting mechanical frame  the ultrasonic motor  the driver of Ultrasonic Motor  the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor  photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system  was introduced the source of the disturbance  and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space  simple configuration  high position control precision  fine repeatability  self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent. 2011 SPIE.  
A fuzzy control method based on information integration for double inverted pendulum (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Digital Manufacturing and Automation, ICDMA 2011, August 5, 2011 - August 7, 2011, Zhangjiajie, Hunan, China
作者:  
Fan Y.
收藏  |  浏览/下载:61/0  |  提交时间:2013/03/25
This article proposes a new fuzzy controller based on information integration. The mathematical model of Linear double inverted pendulum has been studied and estabLished with dynamics analytical method and LQR theory is used to design the optimal Linear inverted pendulum controller  then  the integration technology is used to design the variable parameters self-tuning fuzzy controller. Thereby  the fuzzy controller input variable dimension and the number of fuzzy control rules have been extremely reduced. Two controllers are designed for inverted pendulum system control and the comparison simulation experiments have been done. The results show that the controllers can both reaLize good control  and the fuzzy controller has higher precision  faster response  better stabiLity and robustness. 2011 IEEE.