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A HEVC Video Steganalysis Method Using the Optimality of Motion Vector Prediction
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作者 Jun Li Minqing Zhang +2 位作者 Ke Niu Yingnan Zhang Xiaoyuan Yang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2085-2103,共19页
Among steganalysis techniques,detection against MV(motion vector)domain-based video steganography in the HEVC(High Efficiency Video Coding)standard remains a challenging issue.For the purpose of improving the detectio... Among steganalysis techniques,detection against MV(motion vector)domain-based video steganography in the HEVC(High Efficiency Video Coding)standard remains a challenging issue.For the purpose of improving the detection performance,this paper proposes a steganalysis method that can perfectly detectMV-based steganography in HEVC.Firstly,we define the local optimality of MVP(Motion Vector Prediction)based on the technology of AMVP(Advanced Motion Vector Prediction).Secondly,we analyze that in HEVC video,message embedding either usingMVP index orMVD(Motion Vector Difference)may destroy the above optimality of MVP.And then,we define the optimal rate of MVP as a steganalysis feature.Finally,we conduct steganalysis detection experiments on two general datasets for three popular steganographymethods and compare the performance with four state-ofthe-art steganalysis methods.The experimental results demonstrate the effectiveness of the proposed feature set.Furthermore,our method stands out for its practical applicability,requiring no model training and exhibiting low computational complexity,making it a viable solution for real-world scenarios. 展开更多
关键词 Video steganography video steganalysis motion vector prediction motion vector difference advanced motion vector prediction local optimality
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Optimality在多个场景的时域仿真中高效性的深度研究
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作者 黄刚 吴均 《电子技术应用》 2024年第8期42-47,共6页
随着产品的速率及复杂性越来越高,针对仿真而言,除了要求仿真本身具有非常高的精度外,还对仿真的效率提出了很高的要求。具体到不同的信号模块,如DDR系统或者高速串行信号上,基于速率越来越高,越来越希望仿真给能出“最优解”的配置,例... 随着产品的速率及复杂性越来越高,针对仿真而言,除了要求仿真本身具有非常高的精度外,还对仿真的效率提出了很高的要求。具体到不同的信号模块,如DDR系统或者高速串行信号上,基于速率越来越高,越来越希望仿真给能出“最优解”的配置,例如DDR5颗粒的ODT的最优配置,高速信号芯片的加重均衡的最优配置等参数。那么如何在成百上千种组合的参数中选择相对最优的参数呢?传统的软件只能通过大量的扫描来进行筛选,在仿真时间和工程师的精力两方面都有比较大的耗费。使用Optimality软件,通过分享一些具体的仿真案例,展现软件的智能性,帮助使用者更快速挑选出最优的参数,使DDR及高速串行的仿真工作变得更加轻松,充分体现出Optimality软件的高效性。 展开更多
关键词 optimality DDR5 DDR4 ODT SystemSI 加重均衡
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Tilt Angle Optimality Criteria for Stand Alone PV Systems
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作者 Mohammad Abu-Naser 《Journal of Power and Energy Engineering》 2024年第3期1-18,共18页
The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy avai... The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy availability varies, this criterion may not be optimal. This study explores two alternative optimization criteria focused on maximizing baseload supply potential and minimizing required storage capacity to address seasonality in energy generation. The optimal tilt angles determined for these criteria differed significantly from the standard approach. This research highlights additional factors crucial for designing solar power systems beyond gross energy generation, essential for the global transition towards a fully renewable energy-based electric grid in the future. 展开更多
关键词 Electric Grid Fixed Solar Panels Optimal PV Tilt Angle Seasonal Solar Variability Renewable Energy Supply-Demand Balance
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Hybrid TDOA/FDOA and track optimization of UAV swarm based on A-optimality 被引量:1
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作者 LI Hao SUN Hemin +1 位作者 ZHOU Ronghua ZHANG Huainian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期149-159,共11页
The source location based on the hybrid time difference of arrival(TDOA)/frequency difference of arrival(FDOA) is a basic problem in wireless sensor networks, and the layout of sensors in the hybrid TDOA/FDOA position... The source location based on the hybrid time difference of arrival(TDOA)/frequency difference of arrival(FDOA) is a basic problem in wireless sensor networks, and the layout of sensors in the hybrid TDOA/FDOA positioning will greatly affect the accuracy of positioning. Using unmanned aerial vehicle(UAV) as base stations, by optimizing the trajectory of the UAV swarm, an optimal positioning configuration is formed to improve the accuracy of the target position and velocity estimation. In this paper, a hybrid TDOA/FDOA positioning model is first established, and the positioning accuracy of the hybrid TDOA/FDOA under different positioning configurations and different measurement errors is simulated by the geometric dilution of precision(GDOP) factor. Second, the Cramer-Rao lower bound(CRLB) matrix of hybrid TDOA/FDOA location under different moving states of the target is derived theoretically, the objective function of the track optimization is obtained, and the track of the UAV swarm is optimized in real time. The simulation results show that the track optimization effectively improves the accuracy of the target position and velocity estimation. 展开更多
关键词 unmanned aerial vehicle(UAV)swarm time difference of arrival(TDOA) frequency difference of arrival(FDOA) A-optimality track optimization
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Two-Stage Optimal Dispatching of Wind Power-Photovoltaic-Solar Thermal Combined System Considering Economic Optimality and Fairness
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作者 Weijun Li Xin Die +2 位作者 Zhicheng Ma Jinping Zhang Haiying Dong 《Energy Engineering》 EI 2023年第4期1001-1022,共22页
Aiming at the problems of large-scale wind and solar grid connection,how to ensure the economy of system operation and how to realize fair scheduling between new energy power stations,a two-stage optimal dispatching m... Aiming at the problems of large-scale wind and solar grid connection,how to ensure the economy of system operation and how to realize fair scheduling between new energy power stations,a two-stage optimal dispatching model of wind power-photovoltaic-solar thermal combined system considering economic optimality and fairness is proposed.Firstly,the first stage dispatching model takes the overall economy optimization of the system as the goal and the principle of maximizing the consumption of wind and solar output,obtains the optimal output value under the economic conditions of each new energy station,and then obtains the maximum consumption space of the new energy station.Secondly,based on the optimization results of the first stage,the second stage dispatching model uses the dispatching method of fuzzy comprehensive ranking priority to prioritize the new energy stations,and then makes a fair allocation to the dispatching of the wind and solar stations.Finally,the analysis of a specific example shows that themodel can take into account the fairness of active power distribution of new energy stations on the basis of ensuring the economy of system operation,make full use of the consumption space,and realize the medium and long-term fairness distribution of dispatching plan. 展开更多
关键词 Economic optimality FAIRNESS combined power generation the fuzzy comprehensive ranking priority optimal dispatching
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OPTIMALITY CONDITIONS AND DUALITY RESULTS FOR NONSMOOTH VECTOR OPTIMIZATION PROBLEMS WITH THE MULTIPLE INTERVAL-VALUED OBJECTIVE FUNCTION 被引量:4
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作者 Tadeusz ANTCZAK 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1133-1150,共18页
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult... In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex. 展开更多
关键词 nonsmooth multiobjective programming problem with the multiple interval- objective function Fritz John necessary optimality conditions Karush-Kuhn- Tucker necessary optimality conditions (weakly) LU-efficient solution Mond- Weir duality
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基于Pareto Optimality的PPP项目三大主参与方效用探讨
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作者 陈黎明 赵辉 《沈阳建筑大学学报(社会科学版)》 2011年第4期418-421,共4页
在PPP项目的众多参与方中,选取项目发起人、SPC和贷款银行三个最主要的参与方,通过分析项目发起人与SPC、SPC与贷款银行和贷款银行与项目发起人之间的内在联系,在Pareto Optimality理论分析的基础上,得到三者之间两两优势互补的埃奇沃... 在PPP项目的众多参与方中,选取项目发起人、SPC和贷款银行三个最主要的参与方,通过分析项目发起人与SPC、SPC与贷款银行和贷款银行与项目发起人之间的内在联系,在Pareto Optimality理论分析的基础上,得到三者之间两两优势互补的埃奇沃思方框图,并根据瓦尔拉斯均衡理论得出PPP项目能够实现帕累托最优,实现项目效用的最大化,最后拟画出PPP项目三大主参与方的效用可能性曲线。 展开更多
关键词 PPP PARETO optimality 埃奇沃思 效用
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SECOND-ORDER OPTIMALITY CONDITIONS FOR OPTIMAL CONTROL PROBLEMS GOVERNED BY 3-DIMENSIONAL NEVIER-STOKES EQUATIONS 被引量:5
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作者 王丽娟 何培杰 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期729-734,共6页
This article is concerned with second-order necessary and sufficient optimality conditions for optimal control problems governed by 3-dimensional Navier-Stokes equations. The periodic state constraint is considered.
关键词 Necessary and sufficient optimality conditions optimal control Navier-Stokes equation periodic state constraint
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CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS 被引量:3
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作者 丁小丽 Juan J.NIETO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1003-1013,共11页
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex... Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results. 展开更多
关键词 CONTROLLABILITY optimality neutral equations different fractional orders
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TDOA and track optimization of UAV swarm based on D-optimality 被引量:7
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作者 ZHOU Ronghua SUN Hemin +1 位作者 LI Hao LUO Weilin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1140-1151,共12页
To solve the problem of time difference of arrival(TDOA)positioning and tracking of targets by the unmanned aerial vehicles(UAV)swarm in future air combat,this paper adopts the TDOA positioning method and uses time di... To solve the problem of time difference of arrival(TDOA)positioning and tracking of targets by the unmanned aerial vehicles(UAV)swarm in future air combat,this paper adopts the TDOA positioning method and uses time difference sensors of the UAV swarm to locate target radiation sources.Firstly,a TDOA model for the target is set up for the UAV swarm under the condition that the error variance varies with the received signal-to-noise ratio.The accuracy of the positioning error is analyzed by geometric dilution of precision(GDOP).The D-optimality criterion of the positioning model is theoretically derived.The target is positioned and settled,and the maximum value of the Fisher information matrix determinant is used as the optimization objective function to optimize the track of the UAV in real time.Simulation results show that the track optimization improves the positioning accuracy and stability of the UAV swarm to the target. 展开更多
关键词 time difference of arrival(TDOA) unmanned aerial vehicles(UAV)swarm D-optimality track optimization
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THE OPTIMALITY CONDITIONS OF NONCONVEXSET-VALUED VECTOR OPTIMIZATION 被引量:2
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作者 盛保怀 刘三阳 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期47-55,共9页
The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz Joh... The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz John optimality condition of set-valued vector optimization is established. Finally, under the assumption of pseudoconvexity, the optimality condition is proved to be sufficient. 展开更多
关键词 set-valued derivative optimality condition pseudoconvex set-valued mapping
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Sufficient Optimality Conditions for Multiobjective Programming Involving (V, ρ)h,ψ-type Ⅰ Functions 被引量:3
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作者 ZHANG Qing-xiang JIANG Yan KANG Rui-rui 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期409-416,共8页
New classes of functions namely (V, ρ)_(h,φ)-type I, quasi (V, ρ)_(h,φ)-type I and pseudo (V, ρ)_(h,φ)-type I functions are defined for multiobjective programming problem by using BenTal's generalized algebr... New classes of functions namely (V, ρ)_(h,φ)-type I, quasi (V, ρ)_(h,φ)-type I and pseudo (V, ρ)_(h,φ)-type I functions are defined for multiobjective programming problem by using BenTal's generalized algebraic operation. The examples of (V, ρ)_(h,φ)-type I functions are given. The sufficient optimality conditions are obtained for multi-objective programming problem involving above new generalized convexity. 展开更多
关键词 multiobjective programming (V p)h φ-type I functions Pareto efficient solu-tion sufficient optimality conditions
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Global optimality conditions for quadratic 0-1 programming with inequality constraints 被引量:1
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作者 张连生 陈伟 姚奕荣 《Journal of Shanghai University(English Edition)》 CAS 2010年第2期150-154,共5页
Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are present... Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are presented.The necessary condition is expressed without dual variables.The relations between the global optimal solutions of nonconvex quadratic 0-1 problems and the associated relaxed convex problems are also studied. 展开更多
关键词 quadratic 0-1 programming optimality condition nonconvex optimization integer programming convex duality
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Optimality of Vector Optimization Involving Generalized Type-I Functions in Banach 被引量:1
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作者 QU He-mei XUE Zhen-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期543-550,共8页
In this note,new classes of generalized type-I functions are introduced for functions between Banach spaces.These generalized type-I functions are then utilized to establish sufficient optimality conditions and dualit... In this note,new classes of generalized type-I functions are introduced for functions between Banach spaces.These generalized type-I functions are then utilized to establish sufficient optimality conditions and duality results for a vector optimization problem with functions defined on a Banach space. 展开更多
关键词 vector optimization optimality conditions type-I functions duality
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Optimality conditions and duality for a class of nondifferentiable multiobjective generalized fractional programming problems 被引量:1
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作者 GAO Ying RONG Wei-dong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期331-344,共14页
This paper studies a class of multiobjective generalized fractional programming problems, where the numerators of objective functions are the sum of differentiable function and convex function, while the denominators ... This paper studies a class of multiobjective generalized fractional programming problems, where the numerators of objective functions are the sum of differentiable function and convex function, while the denominators are the difference of differentiable function and convex function. Under the assumption of Calmness Constraint Qualification the Kuhn-Tucker type necessary conditions for efficient solution are given, and the Kuhn-Tucker type sufficient conditions for efficient solution are presented under the assumptions of (F, α, ρ, d)-V-convexity. Subsequently, the optimality conditions for two kinds of duality models are formulated and duality theorems are proved. 展开更多
关键词 operations research multiobjective generalized fractional programming optimality condition duality theorem generalized convexity
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Optimality and Duality on Fractional Multi-objective Programming Under Semilocal E-convexity 被引量:1
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作者 HU Qing-jie XIA O Yun-hai CHEN Nei-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期200-210,共11页
In this paper, some necessary and sufficient optimality conditions are obtained for a fractional multiple objective programming involving semilocal E-convex and related functions. Also, some dual results are establish... In this paper, some necessary and sufficient optimality conditions are obtained for a fractional multiple objective programming involving semilocal E-convex and related functions. Also, some dual results are established under this kind of generalized convex functions. Our results generalize the ones obtained by Preda[J Math Anal Appl, 288(2003) 365-382]. 展开更多
关键词 semilocal E-convex functions fractional multiple objective programming optimality conditions DUALITY
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Optimality Conditions and Duality for Nonsmooth Multiobjective Programms with Generalized Essential Convexity 被引量:1
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作者 王彩玲 刘庆怀 李忠范 《Northeastern Mathematical Journal》 CSCD 2008年第5期377-385,共9页
In this paper, we introduce generalized essentially pseudoconvex function and generalized essentially quasiconvex function, and give sufficient optimality conditions of the nonsmooth generalized convex multi-objective... In this paper, we introduce generalized essentially pseudoconvex function and generalized essentially quasiconvex function, and give sufficient optimality conditions of the nonsmooth generalized convex multi-objective programming and its saddle point theorem about cone efficient solution. We set up Mond-Weir type duality and Craven type duality for nonsmooth multiobjective programming with generalized essentially convex functions, and prove them. 展开更多
关键词 multiobjective programming optimality condition saddle point DUALITY
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Temporal Optimality of a Via-Posture on Trajectory during Sit-to-Stand and Back-to-Sit Movements 被引量:1
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作者 Hiroshi R. Yamasaki Urara Nakamura Hiroshi Nagasaki 《Journal of Biomedical Science and Engineering》 2014年第7期387-396,共10页
The purpose of this study was to examine the hypothesis that the minimum angle-jerk with via-point model could account for the temporal consistency of kinematics in sit-to-stand (STS) and back-to-sit (BTS) movements. ... The purpose of this study was to examine the hypothesis that the minimum angle-jerk with via-point model could account for the temporal consistency of kinematics in sit-to-stand (STS) and back-to-sit (BTS) movements. The positions of bony landmarks on the subjects during the tasks were recorded using a Vicon motion analysis system to yield the angular displacement and position of the center of mass (COM) of a three-link rigid body model in the sagittal plane. Minimum angle-jerk and minimum jerk trajectories with a via-point were computed for joint angle and COM, respectively. Five to six candidate points were selected as the via-point from the measured trajectory based on the separate kinematic events. The results show the optimal angular trajectories using the via-points (via-angles) before the seat-off for STS, and at around the seat-contact for BTS resembles the measured angular trajectories well, indicating that the posture at the via-point was temporally optimal to produce the minimum angle-jerk trajectory for both movements. It is hypothesized that the multi-joint angular patterns during STS and BTS movements were organized to pass through the via-point, namely the via-posture along the minimum angle-jerk trajectory. 展开更多
关键词 Temporal optimality Via-Posture TRAJECTORY SIT-TO-STAND Back-to-Sit
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Necessary Optimality Conditions for Multi-Objective Semi-Infinite Variational Problem 被引量:1
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作者 Bharti Sharma Promila Kumar 《American Journal of Operations Research》 2016年第1期36-43,共8页
In this paper, necessary optimality conditions for a class of Semi-infinite Variational Problems are established which are further generalized to a class of Multi-objective Semi-Infinite Variational Problems. These co... In this paper, necessary optimality conditions for a class of Semi-infinite Variational Problems are established which are further generalized to a class of Multi-objective Semi-Infinite Variational Problems. These conditions are responsible for the development of duality theory which is an extremely important feature for any class of problems, but the literature available so far lacks these necessary optimality conditions for the stated problem. A lemma is also proved to find the topological dual of  as it is required to prove the desired result. 展开更多
关键词 SEMI-INFINITE Variational Problem Efficient Solution Necessary optimality Conditions
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Sympathy Theory: New development in Optimality Theory
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作者 Zuo Yan 《现代外语》 CSSCI 北大核心 1999年第3期308-309,共2页
关键词 SYMPATHY THEORY optimality THEORY PHONOLOGICAL OPACITY SYMPATHETIC candidate
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