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Effect of normalized plasma frequency on electron phase-space orbits in a free-electron laser 被引量:2
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作者 吉驭嫔 王时建 +5 位作者 徐竟跃 徐勇根 刘晓旭 卢宏 黄小莉 张世昌 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期242-246,共5页
Irregular phase-space orbits of the electrons are harmful to the electron-beam transport quality and hence deteriorate the performance of a free-electron laser (FEL). In previous literature, it was demonstrated that... Irregular phase-space orbits of the electrons are harmful to the electron-beam transport quality and hence deteriorate the performance of a free-electron laser (FEL). In previous literature, it was demonstrated that the irregularity of the electron phase-space orbits could be caused in several ways, such as varying the wiggler amplitude and inducing sidebands. Based on a Hamiltonian model with a set of self-consistent differential equations, it is shown in this paper that the electron- beam normalized plasma frequency functions not only couple the electron motion with the FEL wave, which results in the evolution of the FEL wave field and a possible power saturation at a large beam current, but also cause the irregularity of the electron phase-space orbits when the normalized plasma frequency has a sufficiently large value, even if the initial energy of the electron is equal to the synchronous energy or the FEL wave does not reach power saturation. 展开更多
关键词 free-electron laser electron phase-space orbit normalized plasma frequency IRREGULARITY
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Construction of Plant Landscape Spaces in Colleges and Universities:Taking Jiangxi Normal University as an example
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作者 Xiaogang CHEN Ziyuan SHU Hui LIN 《Asian Agricultural Research》 2019年第10期44-49,共6页
Landscape in colleges and universities is mainly composed of plant landscape.Plant space landscape has a profound impact on the campus landscape construction.This paper investigates and analyzes four plant landscape s... Landscape in colleges and universities is mainly composed of plant landscape.Plant space landscape has a profound impact on the campus landscape construction.This paper investigates and analyzes four plant landscape space plots in the Yaohu Campus of Jiangxi Normal University to understand their characteristics,in order to provide reference for the construction of plant landscape space in southern colleges and universities. 展开更多
关键词 GARDEN plants LANDSCAPE space JIANGXI normal University
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Normality and Its Variants on Fuzzy Isotone Spaces
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作者 Stephen M. Gathigi Moses N. Gichuki +1 位作者 Paul A. Otieno Hezron S. Were 《Advances in Pure Mathematics》 2013年第7期639-642,共4页
The study of fuzzy sets is specifically designed to mathematically represent uncertainty and vagueness by assigning values of membership to objects that belong to a particular set. This notion has been broadly extende... The study of fuzzy sets is specifically designed to mathematically represent uncertainty and vagueness by assigning values of membership to objects that belong to a particular set. This notion has been broadly extended to other areas of topology where various topological concepts have been shown to hold on fuzzy topology. Some notions naturally extend to closure spaces without requiring a lot of modification of the underlying topological ideas. This work investigates the variants of normality on fuzzy isotone spaces. 展开更多
关键词 FUZZY Sets FUZZY CLOSURE space FUZZY Isotone space FUZZY normalITY
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New Common Fixed Point Results for Four Maps on Cone Metric Spaces 被引量:12
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作者 Yan Han Shaoyuan Xu 《Applied Mathematics》 2011年第9期1114-1118,共5页
In this paper, some new existence and uniqueness of common fixed points for four mappings are obtained, which do not satisfy continuity and commutation on non-normal cone metric spaces. These results improve and gener... In this paper, some new existence and uniqueness of common fixed points for four mappings are obtained, which do not satisfy continuity and commutation on non-normal cone metric spaces. These results improve and generalize several well-known comparable results in the literature. 展开更多
关键词 COMMON Fixed Point CONE METRIC space Non-normal CONE
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Common Fixed Points under Contractive Conditions in Cone Metric Spaces 被引量:1
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作者 WANG Yun-jie ZHU Jiang 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期47-52,共6页
In order to develop and improve the fixed point theorems in cone metric spaces, some new fixed point theorems are presented for two mappings in cone metric spaces which satisfy contractive conditions, where the cone i... In order to develop and improve the fixed point theorems in cone metric spaces, some new fixed point theorems are presented for two mappings in cone metric spaces which satisfy contractive conditions, where the cone is not necessarily normal. Our results generalize fixed point theorems of Abbas, Jungck and Stojan Radenovi in cone metric spaces. 展开更多
关键词 cone metric space normal and non-normal cone common fixed point
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Methodology of Wavelets in Relativistic Heavy Ion Collisions in One Dimensional Phase Space (<i>η</i>-Space) 被引量:1
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作者 Vyacheslav V. Lyashenko M. Ayaz Ahmad +1 位作者 Zhanna V. Deineko Mir Hashim Rasool 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第2期254-266,共13页
An attempt has been made to apply the wavelet methodology for the study of the results of the chaotic behavior of multiparticle production in relativistic heavy ion collisions. We reviewed the data that describes the ... An attempt has been made to apply the wavelet methodology for the study of the results of the chaotic behavior of multiparticle production in relativistic heavy ion collisions. We reviewed the data that describes the collisions of relativistic heavy ion for the case η-space in 1-D phase space of variable. We compared the experimental data and UrQMD data using wavelet coherency. We discussed the results of the comparison. 展开更多
关键词 WAVELET Coherence Morlet WAVELET Heavy Ion Collisions Reaction Dynamics Phase space normalized FACTORIAL MOMENTS
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Unique Common Fixed Point Theorems for Lipschitz Type Mappings under c-Distance on Cone Metric Spaces
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作者 Yongjie PIAO 《Journal of Mathematical Research with Applications》 CSCD 2014年第6期713-722,共10页
In this paper, new unique common fixed point theorems for four mappings satisfying Lipzchitz type conditions in the term of c-distance on normal cone metric spaces were given.The obtained results generalize and improv... In this paper, new unique common fixed point theorems for four mappings satisfying Lipzchitz type conditions in the term of c-distance on normal cone metric spaces were given.The obtained results generalize and improve many known common fixed point theorems. 展开更多
关键词 normal cone metric space c-distance common fixed point Lipschitz type condition
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EXISTENCE THEOREMS OF SOLUTIONS FOR TWO-POINT BOUNDARY VALUE PROBLEM OF SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS IN BANACH SPACES
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作者 张石生 王凡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第2期99-108,共10页
By using partial order method. some existing theorems of solutions for two-point bouniary value problem of second order ordinary differenlial equations in Banach spaces are given.
关键词 two-point boundary value problem weakly sequentially complete Banach space normal cone
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Strong convergence theorems for nonexpansive semi-groups in Banach spaces 被引量:2
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作者 张石生 杨莉 柳京爱 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第10期1287-1297,共11页
Some strong convergence theorems of explicit composite iteration scheme for nonexpansive semi-groups in the framework of Banach spaces are established. Results presented in the paper not only extend and improve the co... Some strong convergence theorems of explicit composite iteration scheme for nonexpansive semi-groups in the framework of Banach spaces are established. Results presented in the paper not only extend and improve the corresponding results of ShiojiTakahashi, Suzuki, Xu and Aleyner-Reich, but also give a partially affirmative answer to the open questions raised by Suzuki and Xu. 展开更多
关键词 nonexpansive semi-group demi-closed principle common fixed point uni-formly smooth Banach space weakly continuous normalized duality mapping
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Study of Wavelet Methodology and Chaotic Behavior of Produced Particles in Different Phase Spaces of Relativistic Heavy Ion Collisions
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作者 M. Ayaz Ahmad Vyacheslav V. Lyashenko +2 位作者 Zhanna V. Deineko Jalal Hasan Baker Shafiq Ahmad 《Journal of Applied Mathematics and Physics》 2017年第5期1130-1149,共20页
We applied the wavelet methodology for our earlier published research work of the chaotic behavior so called multiplicity fluctuations of secondary charged particles produced during the nucleus-nucleus (A-A) collision... We applied the wavelet methodology for our earlier published research work of the chaotic behavior so called multiplicity fluctuations of secondary charged particles produced during the nucleus-nucleus (A-A) collisions at an energy of the order of ≈ 409 GeV in a new fashion. We illustrated the wavelet coherency in a relation of chaotic behavior for above said data of secondary charged pions in different phase spaces of collisions such as: η-space, φ-space (in one dimension) and ηφ-space (in two dimensions) respectively. We have shown the changes in the wavelet coherence when there are different values of two parameters “q” and “p”. We discussed our new results for the comparison purpose and findings were in the good agreements. 展开更多
关键词 WAVELET Coherence Morlet WAVELET Dynamics of Nucleus-Nucleus (A-A) Collisions Phase space normalized FACTORIAL Moments (SFMs)
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Supplying Conditions for Having up to 1000 Degrees of Freedom in the Onset of Inflation, Instead of 2 to 3 Degrees of Freedom, Today, in Space-Time
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第1期143-151,共9页
The following document attempts to answer the role additional degrees of freedom have as to initial inflationary cosmology, i.e. the idea is to cut down on the number of independent variables to get as simple an emerg... The following document attempts to answer the role additional degrees of freedom have as to initial inflationary cosmology, i.e. the idea is to cut down on the number of independent variables to get as simple an emergent space time structure of entropy and its generation as possible. One parameter being initial degrees of freedom, the second the minimum allowed grid size in space time, and the final parameter being emergent space time temperature. In order to initiate this inquiry, a comparison is made to two representations of a scale evolutionary Friedman equation, with one of the equations based upon LQG, and another involving an initial Hubble expansion parameter with initial temperature used as an input into T4 times N(T). Initial assumptions as to the number of degrees of freedom have for a maximum value of N(T) ~ 103. Making that upper end approximation for the value of permissible degrees of freedom is dependent upon a minimum grid size length as of about centimeters. Should the minimum uncertainty grid size for space time be higher than centimeters, then top value degrees of freedom of phase space as given by a value N(T) ~ 103 drops. In addition, the issue of bits, i.e. information is shown to not only have temperature dependence, but to be affected by minimum “grid size” as well. 展开更多
关键词 ENTROPY Emergent space Time normalized Energy DENSITY
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Feedback Systems on a Reflexive Banach Space—Linearization
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作者 Messaoudi Khelifa 《International Journal of Modern Nonlinear Theory and Application》 2020年第2期34-50,共17页
The aim of our work is to formulate and demonstrate the results of the normality, the Lipschitz continuity, of a nonlinear feedback system described by the monotone maximal operators and hemicontinuous, defined on rea... The aim of our work is to formulate and demonstrate the results of the normality, the Lipschitz continuity, of a nonlinear feedback system described by the monotone maximal operators and hemicontinuous, defined on real reflexive Banach spaces, as well as the approximation in a neighborhood of zero, of solutions of a feedback system [A,B] assumed to be non-linear, by solutions of another linear, This approximation allows us to obtain appropriate estimates of the solutions. These estimates have a significant effect on the study of the robust stability and sensitivity of such a system see <a href="#ref1">[1]</a> <a href="#ref2">[2]</a> <a href="#ref3">[3]</a>. We then consider a linear FS <img src="Edit_4629d4d0-bbb2-478d-adde-391efde3d1e0.bmp" alt="" />, and prove that, if <img src="Edit_435aae08-e821-4b4d-99d2-e2a2b47609c1.bmp" alt="" />;<img src="Edit_4fa030bc-1f97-4726-8257-ca8d00657aac.bmp" alt="" /> , with <img src="Edit_63ab4faa-ba40-45fe-8b8a-7a6caef91794.bmp" alt="" />the respective solutions of FS’s [A,B] and <img src="Edit_e78e2e6d-8934-4011-93eb-8b7eb52fa856.bmp" alt="" /> corresponding to the given (u,v) in <img src="Edit_0e18433c-8c7a-454f-8eec-6eb9fb69469a.bmp" alt="" /> . There exists,<img src="Edit_3dcd8afc-8cea-4c06-a920-e4148a5f793e.bmp" alt="" />, positive real constants such that, <img src="Edit_edb88446-3e39-4fe0-865a-114de701e78e.bmp" alt="" />. These results are the subject of theorems 3.1, <span style="font-size:10.0pt;font-family:;" "="">... </span>, 3.3. The proofs of these theorems are based on our lemmas 3.2, <span style="font-size:10.0pt;font-family:;" "="">... </span>, 3.5, devoted according to the hypotheses on A and B, to the existence of the inverse of the operator <em>I+BA</em> and <img src="Edit_2db1326b-cb5b-44cf-8d1f-df22bd6da45f.bmp" alt="" />. The results obtained and demonstrated along this document, present an extension in general Banach space of those in <a href="#ref4">[4]</a> on a Hilbert space <em>H</em> and those in <a href="#ref5">[5]</a> on a extended Hilbert space <img src="Edit_b70ce337-1812-4d4b-ae7d-a24da7e5b3cf.bmp" alt="" />. 展开更多
关键词 Nonlinear Feedback System LINEARIZATION Reflexive Banach space normalITY Lipschitz Continuity
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Aggregation of Priorities in Multi-Criteria Decision Analysis (MCDA): Connecting Decision Spaces in the Cognitive Space
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作者 Sajjad Zahir 《American Journal of Operations Research》 2016年第4期317-333,共17页
In Multi-Criteria Decision Analysis, the well-known weighted sum method for aggregating normalised relative priorities ignores the unit of scale that may vary across the criteria and thus causes rank reversals. A new ... In Multi-Criteria Decision Analysis, the well-known weighted sum method for aggregating normalised relative priorities ignores the unit of scale that may vary across the criteria and thus causes rank reversals. A new aggregation rule that explicitly includes the norms of priority vectors is derived and shown as a remedy for it. An algorithmic procedure is presented to demonstrate how it can as well be used in the Analytic Hierarchy Process when norms of priority vectors are not readily available. Also, recursion relations connecting two decision spaces with added or deleted alternatives give an opportunity to extend the idea of connectivity to a new concept of cognitive space. Expanded analytic modelling embracing multiple decision spaces or scenarios may assist in detecting deficiencies in analytic models and also grasping the big picture in decision making. 展开更多
关键词 AGGREGATION normalIZATION Decision space Cognitive space Analytic Hierarchy Process Scenario
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Coupled Extremal Quasi-solutions to Nonlinear Impulsive Fredholm Integral Equations in Banach Spaces
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作者 戚仕硕 《Northeastern Mathematical Journal》 CSCD 2000年第3期329-338,共10页
By means of the method of coupled lower and upper quasisolutio ns, the paper applies, instead of establishing the comparison theorem, a new ite rative technique to nonlinear impulsive Fredholm integral equations in ... By means of the method of coupled lower and upper quasisolutio ns, the paper applies, instead of establishing the comparison theorem, a new ite rative technique to nonlinear impulsive Fredholm integral equations in Banach sp aces and proves the existence theorem on their coupled extremal quasisolutions . Finally, an infinite system of nonlinear impulsive integral equations is provi ded to demonstrate the obtained results. 展开更多
关键词 coupled lower and upper quasi-solutions iterative techn ique impulsive Fredholm integral equation Banach space normal cone
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Formation, Propagation and Reflection of 1D Normal Shocks in Riemann Shock Tube
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作者 Karan S. Surana Jacob K. Kendall Celso H. Carranza 《Applied Mathematics》 2022年第3期295-323,共29页
The purpose of this paper is to consider 1D Riemann shock tube to investigate the formation and propagation of compression waves leading to formation, propagation and reflection of 1D normal shocks using simplified ma... The purpose of this paper is to consider 1D Riemann shock tube to investigate the formation and propagation of compression waves leading to formation, propagation and reflection of 1D normal shocks using simplified mathematical models commonly used in the published work as well as using complete mathematical models based on Conservation and Balance Laws (CBL) of classical continuum mechanics and constitutive theories for compressible viscous medium derived using entropy inequality and representation theorem. This work is aimed at resolving compression waves, the shock structure, shock formation, propagation and reflection of fully formed shocks. Evolutions obtained from the mathematical models always satisfy differentiability requirements in space and time dictated by the highest order of the derivatives of the dependent variables in the mathematical models investigated. All solutions reported in this paper including boundary conditions and initial conditions are always analytic. Solutions of the mathematical models are obtained using the space-time finite element method in which the space-time integral forms are space-time variationally consistent ensuring unconditionally stable computations during the entire evolution. Solution for a space-time strip or slab is calculated and is time marched upon convergence to obtain complete evolution for the desired space-time domain, thus ensuring time accurate evolutions. The space-time local approximation over a space-time element of a space-time strip or slab is p-version hierarchical with higher-order global differentiability in space and time, i.e., we consider scalar product approximation spaces in which k = (k<sub>1</sub>, k<sub>2</sub>) are the order of the space in space and time and p = (p<sub>1</sub>, p<sub>2</sub>) are p-levels of the approximations in space and time. Model problem studies are presented for different mathematical models and are compared with solutions obtained from the complete mathematical model based on CBL and constitutive theories for viscous compressible medium to illustrate the deficiencies and shortcomings of the simplified and approximate models in simulating correct physics of normal shocks. 展开更多
关键词 Compression Wave 1D normal Shock Riemann Shock Tube space-TIME
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COMPLETE SPACE-LIKE SUBMANIFOLDS IN LOCALLY SYMMETRIC SEMI-DEFINITE SPACES
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作者 XuSenlin ChenDongmei 《Analysis in Theory and Applications》 2004年第4期383-390,共8页
The purpose of this paper is to study complete space-like submanifolds with parallel mean curvature vector and flat normal bundle in a locally symmetric semi-defnite space satisfying some curvature conditions. We firs... The purpose of this paper is to study complete space-like submanifolds with parallel mean curvature vector and flat normal bundle in a locally symmetric semi-defnite space satisfying some curvature conditions. We first give an optimal estimate of the Laplacian of the squared norm of the second fundamental form for such submanifold. Furthermore, the totally umbilical submanifolds are characterized. 展开更多
关键词 space-like submanifolds constant mean curvature flat normal bundle second fundamental form locally symmetric semi-definite space
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Atlas Compatibility Transformation:A Normal Manifold Learning Algorithm
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作者 Zhong-Hua Hao Shi-Wei Ma Fan Zhao 《International Journal of Automation and computing》 EI CSCD 2015年第4期382-392,共11页
Over the past few years,nonlinear manifold learning has been widely exploited in data analysis and machine learning.This paper presents a novel manifold learning algorithm,named atlas compatibility transformation(ACT)... Over the past few years,nonlinear manifold learning has been widely exploited in data analysis and machine learning.This paper presents a novel manifold learning algorithm,named atlas compatibility transformation(ACT),It solves two problems which correspond to two key points in the manifold definition:how to chart a given manifold and how to align the patches to a global coordinate space based on compatibility.For the first problem,we divide the manifold into maximal linear patch(MLP) based on normal vector field of the manifold.For the second problem,we align patches into an optimal global system by solving a generalized eigenvalue problem.Compared with the traditional method,the ACT could deal with noise datasets and fragment datasets.Moreover,the mappings between high dimensional space and low dimensional space are given.Experiments on both synthetic data and real-world data indicate the effection of the proposed algorithm. 展开更多
关键词 Nonlinear dimensionality reduction manifold learning normal vector field maximal linear patch ambient space.
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New Fixed Point Results of Generalized g-Quasi-Contractions in Cone b-Metric Spaces Over Banach Algebras 被引量:1
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作者 Shaoyuan Xu Suyu Cheng +1 位作者 Suzana Aleksic Yongjie Piao 《Analysis in Theory and Applications》 CSCD 2017年第2期118-133,共16页
In this paper, we introduce the concept of generalized g-quasi-contractions in the setting of cone b-metric spaces over Banach algebras. By omitting the assump- tion of normality we establish common fixed point theore... In this paper, we introduce the concept of generalized g-quasi-contractions in the setting of cone b-metric spaces over Banach algebras. By omitting the assump- tion of normality we establish common fixed point theorems for the generalized g- quasi-contractions with the spectral radius r(λ) of the g-quasi-contractive constant vector λ satisfying r(λ) ∈[0,1) in the setting of cone b-metric spaces over Banach al- gebras, where the coefficient s satisfies s ≥ 1. The main results generalize, extend and unify several well-known comparable results in the literature. 展开更多
关键词 Cone b-metric spaces over Banach algebras non-normal cones c-sequences general-ized g-quasi-contractions fixed point theorems.
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基于可形变规范化点云的三维人脸重建
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作者 刘姝 张宇峰 +2 位作者 王科选 潘昱杉 王皓 《小型微型计算机系统》 北大核心 2025年第12期2927-2933,共7页
为了从单幅二维人脸图像中重建出高质量的三维人脸模型,本文提出一种可形变规范化点云的三维人脸重建方法DNPR.DNPR跳出显式人脸先验模型的固定拓扑方式,将人脸表示为规范空间中与姿态无关的几何形状和外观的点云,通过优化规范空间中的... 为了从单幅二维人脸图像中重建出高质量的三维人脸模型,本文提出一种可形变规范化点云的三维人脸重建方法DNPR.DNPR跳出显式人脸先验模型的固定拓扑方式,将人脸表示为规范空间中与姿态无关的几何形状和外观的点云,通过优化规范空间中的可学习点,使其在映射空间和着色空间中进行有效的变形和渲染,加速向目标人脸形状收敛,且训练后期的密集点可以很好地再现纹理细节.在IMavatar提供的基准数据集上的对比实验表明,DNPR的平均结构相似性达到0.854,平均峰值信噪比达到23.863,相较于多数传统隐式重建方法,表现出一定的优势.且训练速度为0.06h/轮次,相比于PointAvatar提高了4个百分点. 展开更多
关键词 三维人脸模型 可形变规范化点云 映射空间 着色空间
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Modeling and Simulation Study of Space Data Link Protocol
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作者 Ismail Hababeh Rizik M. H. Al-Sayyed +2 位作者 Ja’far Alqatawna Yousef Majdalawi Marwan Nabelsi 《International Journal of Communications, Network and System Sciences》 2014年第10期440-452,共13页
This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). ... This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis. 展开更多
关键词 Consultative COMMITTEE for space DATA Systems Standards space DATA Link PROTOCOL Mean END-TO-END Packet Delay Maximum Achievable Application Layer Throughput normalized PROTOCOL OVERHEAD Telecommand spacecrafts space Instruments
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