检索结果-南通市图书馆

Journal of Systems Engineering and Electronics 2010年第4期21卷 623-628页

作者： peng Wu ming Yang Control and Simulation Center Harbin Institute of Technology Harbin 150001 E R. China

Aimed at the guidance requirements of some missiles which attack targets with terminal impact angle at the terminal point,a new integrated guidance and control design scheme based on variable structure control approach for missile with terminal impact angle constraint is ***,a mathematical model of an integrated guidance and control model in pitch plane is established,and then nonlinear transformation is employed to transform the mathematical model into a standard form suitable for sliding mode control method design.A sufficient condition for the existence of linear sliding surface is given in terms of linear matrix inequalities（LMIs）,based on which the corresponding reaching motion controller is also *** verify the effectiveness of the proposed integrated design scheme,the numerical simulation of missile is *** simulation results demonstrate that the proposed guidance and control law can guide missile to hit the target with desired impact angle and desired flight attitude angle simultaneously.

关键词： guidance terminal impact angle sliding mode control integrated guidance and control linear matrix inequality(LMI).

Fast method for spreading sequence estimation of DSSS signal based on maximum likelihood function

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2010年第6期21卷 948-953页

作者： Yanhua peng Bin Tang ming Lv College of Electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 E R. China

To estimate the spreading sequence of the direct sequence spread spectrum (DSSS) signal, a fast algorithm based on maximum likelihood function is proposed, and the theoretical derivation of the algorithm is provided. By simplifying the objective function of maximum likelihood estimation, the algorithm can realize sequence synchronization and sequence estimation via adaptive iteration and sliding window. Since it avoids the correlation matrix computation, the algorithm significantly reduces the storage requirement and the computation complexity. Simulations show that it is a fast convergent algorithm, and can perform well in low signal to noise ratio (SNR).

关键词： direct sequence spread spectrum (DSSS) signal spreading sequence maximum likelihood estimation (MLE).

Emergency treatment and anesthesia management of internal carotid artery injury during neurosurgery:Four case reports

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第27期10卷 9865-9872页

作者： Jie Wang Yu-ming peng Department of Anesthesiology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China

BACKGROUND During skull base surgery,intraoperative internal carotid artery(ICA) injury is a catastrophic complication that can lead to fatal blood loss or secondary cerebral *** management of ICA injury plays a crucial role in the prognosis of *** have reported multiple techniques and management strategies;however,the literature on managing this complication from the anesthesiologist’s perspective is limited,especially in the aspect of circulation management and airway management when patients need transit for further endovascular *** SUMMARY We describe 4 cases of ICA injury during neurosurgery;there were 3 cases of pathologically proven pituitary adenoma and 1 case of cavernous sinus endothelial *** the onset of ICA injury,all four patients were immediately transferred for endovascular therapy under general anesthesia with vital signs monitored and mechanical *** patients were transferred to the hybrid operating room,and one patient was transferred to the catheter operating *** patients underwent covered stent implantation,and one patient underwent *** four patients experienced hypovolemic shock and received blood products infusion and vasoactive drugs to maintain stable *** the neurosurgery,one patient was extubated and returned to the ward,and the other three were delayed tracheal extubation and returned to the intensive care *** patient died from serious neurological complications after 62 d in the hospital,but the other three showed good clinical *** ICA injury imposes a high risk of massive hemorrhage and subsequent *** treatment is critical and requires interdisciplinary collaboration among neurosurgeons,anesthesiologists,and interventional *** hemostatic methods,stable hemodynamics sufficient to ensure perfusion of vital organs,airway safety during transit,rapid localization and implementa

关键词： Complication Internal carotid artery injury Neurosurgery Anesthesia Management Literature review Case reports

SAR target detection based on the optimal fractional Gabor spectrum feature

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Electronic Science and Technology 2023年第2期21卷 55-64页

作者： Ling-Bing peng Yu-Qing Wang Ying-Pin Chen Zhen-ming peng School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu611731China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun130033China Institute of Optics and Electronics Chinese Academy of SciencesChengdu610209China School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu611731China School of Physics and Information Engineering Minnan Normal UniversityZhangzhou363000China

In this paper,an algorithm based on a fractional time-frequency spectrum feature is proposed to improve the accuracy of synthetic aperture radar(SAR)target *** extending the fractional Gabor transform(FrGT)into two dimensions,the fractional time-frequency spectrum feature of an image can be *** the achievement process,we search for the optimal order and design the optimal window function to accomplish the two-dimensional optimal ***,the energy attenuation gradient(EAG)feature of the optimal time-frequency spectrum is extracted for high-frequency *** simulation results show the proposed algorithm has a good performance in SAR target detection and lays the foundation for recognition.

关键词： Optimal fractional Gabor transform(FrGT) Optimal order Synthetic aperture radar(SAR)target detection Time-frequency spectrum analysis

Self-standing 3D nanoporous Ag_(2)Al with abundant surface oxygen species facilitating oxygen electroreduction for efficient hybrid Zn battery

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第7期30卷 345-354页

作者： ming peng Yang Zhao Jiao Lan Yijin Qiao Yongwen Tan College of Materials Science and Engineering Hunan UniversityChangsha 410082HunanChina

The hybrid battery integrating a typical Zn redox battery and a Zn-air battery is a promising green technology for energy storage,and the cathode integrating the redox reaction and electrocatalytic oxygen reduction is a key point for efficient electrochemical energy ***,we report a scalable strategy to fabricate nanoporous Ag2 Al internetallic compound as a self-standing cathode for the hybrid Zn *** abundant surface oxygen species,the Ag-Al intermetallic interaction and the npAg_(2)Al@AgAlOx interface cooperatively contributed to the catalytic ORR *** electrode endows efficient catalytic oxygen reduction(a Tafel slope of 38.0 mV/dec and an onset potential of 0.998 V)and regulated redox activity as compared with *** nanoporous channels allow efficient ion transport,interface charge exchange and gas molecular ***,the assembled hybrid Zn-Ag_(2) Al/air battery delivers a high capacity of 3.23 mAh/cm^(2) as compared with recent *** far as we know,this is the first exploration for the electrochemical property of Ag2 Al,and it would inspire more exploration in developing multifunctional materials and robust hybrid batteries for practical applications.

关键词： Nanoporous metal Ag_(2)Al Oxygen reduction Intermetallic interaction Hybrid battery

Improving the accuracy of pose prediction in molecular docking via structural fltering and conformational clustering

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2013年第11期24卷 1001-1004页

作者： Shi-ming peng Yu Zhou Niu Huang College of Biological Sciences China Agricultural University National Institute of Biological Sciences College of Life Sciences Beijing Normal University

Structure-based virtual screening（molecular docking）is now one of the most pragmatic techniques to leverage target structure for ligand *** binding pose prediction is critical to molecular ***,we describe a general strategy to improve the accuracy of docking pose prediction by implementing the structural descriptor-based fltering and KGS-penalty function-based conformational clustering in an unbiased *** assessed our method against 150 high-quality protein–ligand complex ***,such simple components are suffcient to improve the accuracy of docking pose *** success rate of predicting near-native docking pose increased from 53%of the targets to 78%.We expect that our strategy may have general usage in improving currently available molecular docking programs.

关键词： Molecular docking Pose prediction Structural descriptor Conformational clustering

Blow up of Solutions for a Nonlinear Petrovsky Type Equation with Time-dependent Coefficients

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2020年第4期36卷 836-846页

作者： Xiao-xiao ZHENG Ya-dong SHANG Xiao-ming peng School of Mathematical Sciences Qufu Normal UniversityQufu 273155China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China School of Statistics and Mathematics Guangdong University of Finance and EconomicsGuangzhou 510320China

4In this paper,we study a nonlinear Petrovsky type equation with nonlinear weak damping,a superlinear source and time-dependent coefficients utt+△^2u-ki(t)|ut|m^2ut=k2(t)|u|^p-2u,x∈Ω,t>0,whereΩis a bounded domain in R^*** certain conditions on k1(t),k2(t)and the initial-boundary data,the upper bound for blow-up time of the solution with negative initial energy function is given by means of an auxiliary functional and an energy estimate met hod if p>***,a lower bound of blow-up time are obtained by using a Sobolev-type inequality and a first order differential inequality technique for n=2,3 and n>4.

关键词： nonlinear Petrovsky type equation time-dependent coefficients blow-up upper bound lower bound

An Explicit Lower Bound for Blow Up Time in a Class of Nonlinear Wave Equations with Nonlinear Damping and Source Terms

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2021年第1期37卷 148-154页

作者： Xiao-ming peng Ya-dong SHANG Xue-qin WANG School of Statistics and Mathematics Guangdong University of Finance and EconomicsGuangzhou 510320China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou 510642China

This paper deals with an initial boundary value problem for a class of nonlinear wave equation with nonlinear damping and source terms whose solution may blow up in finite *** explicit lower bound for blow up time is ... 详细信息

关键词： lower bound blow up nonlinear wave equation nonlinear damping nonlinear source

Multi-types of Skyrmions in SU（N） Quantum Hall System

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2005年第2X期44卷 371-374页

作者： LIU Xin DUAN Yi-Shi ZHANG peng-ming Department of Mathematics University of Queensland QLD 4072 Australia Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China Department of Mathematics Lanzhou University Lanzhou 730000 China

The skyrmions in SU（N） quantum Hall （QH） system are discussed. By analyzing the gauge field structure and the topological properties of this QH system it is pointed out that in the SU（N） QH system there can exist （N-1） types of skyrmion structures, instead of only one type of skyrmions. In this paper, by means of the Abelian projections according to the （N - 1） Cartan subalgebra local bases, we obtain the （N - 1） U（1） electromagnetic field tensors in the SU（N） gauge field of the QH system, and then derive （N - 1） types of skyrmion structures from these U（1） sub-field tensors. Furthermore, in light of the C-mapping topological current method, the topological charges and the motion of these skyrmions are also discussed.

关键词： skyrmions quantum hall system topological field theory

Topological Structure and Topological Tensor Current of Gauss-Bonnet-Chern Theorem

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第5期45卷 793-798页

作者： DUAN Yi-Shi WU Shao-Feng ZHANG peng-ming Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China Department of Mathematics Lanzhou University Lanzhou 730000 China

We offer an intrinsic theoretical framework to reveal the inner relationships among three theories for Euler characteristic number, including Gauss Bonnet-Chern theorem, Hop-Poincaré theorem and Morse theory. Moreover, we consider the Gauss Bonnet-Chern （GBC） form imbedded in arbitrary higher-dimensional manifold, which suggests a Hodge dual tensor current. We show the brane structure inherent in the GBC tensor current and obtain the generalized Nambu action for the multi branes with quantized topological charge.

关键词： Gauss-Bonnet-Chern theorem topological tensor current branes