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Completeness of bounded model checking temporal logic of knowledge 被引量:1
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作者 刘志锋 葛云 +1 位作者 章东 周从华 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期399-405,共7页
In order to find the completeness threshold which offers a practical method of making bounded model checking complete, the over-approximation for the complete threshold is presented. First, a linear logic of knowledge... In order to find the completeness threshold which offers a practical method of making bounded model checking complete, the over-approximation for the complete threshold is presented. First, a linear logic of knowledge is introduced into the past tense operator, and then a new temporal epistemic logic LTLKP is obtained, so that LTLKP can naturally and precisely describe the system's reliability. Secondly, a set of prior algorithms are designed to calculate the maximal reachable depth and the length of the longest of loop free paths in the structure based on the graph structure theory. Finally, some theorems are proposed to show how to approximate the complete threshold with the diameter and recurrence diameter. The proposed work resolves the completeness threshold problem so that the completeness of bounded model checking can be guaranteed. 展开更多
关键词 bounded model checking temporal logics of knowledge multi-agent system
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Improved shape hardening function for bounding surface model for cohesive soils 被引量:1
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作者 Andrés Nieto-Leal Victor N.Kaliakin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第4期328-337,共10页
A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement i... A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement is realized without any changes to the simple elliptical shape of the bounding surface, and actually reduces the number of parameters associated with the model by one. 展开更多
关键词 Constitutive model bounding surface plasticity Shape hardening function Clay
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Interval analysis method and convex models for impulsive response of structures with uncertain-but-bounded external loads 被引量:7
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作者 Zhiping Qiu Xiaojun Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第3期265-276,共12页
Two non-probabilistic, set-theoretical methods for determining the maximum and minimum impulsive responses of structures to uncertain-but-bounded impulses are presented. They are, respectively, based on the theories o... Two non-probabilistic, set-theoretical methods for determining the maximum and minimum impulsive responses of structures to uncertain-but-bounded impulses are presented. They are, respectively, based on the theories of interval mathematics and convex models. The uncertain-but-bounded impulses are assumed to be a convex set, hyper-rectangle or ellipsoid. For the two non-probabilistic methods, less prior information is required about the uncertain nature of impulses than the probabilistic model. Comparisons between the interval analysis method and the convex model, which are developed as an anti-optimization problem of finding the least favorable impulsive response and the most favorable impulsive response, are made through mathematical analyses and numerical calculations. The results of this study indicate that under the condition of the interval vector being determined from an ellipsoid containing the uncertain impulses, the width of the impulsive responses predicted by the interval analysis method is larger than that by the convex model; under the condition of the ellipsoid being determined from an interval vector containing the uncertain impulses, the width of the interval impulsive responses obtained by the interval analysis method is smaller than that by the convex model. 展开更多
关键词 Impulsive response Interval analysis method Convex model Uncertain-but-bounded impulse
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Metallogenic model and prognosis of the Shuiyindong super-large strata-bound Carlin-type gold deposit, southwestern Guizhou Province, China 被引量:10
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作者 ZHANG Yu XIA Yong +4 位作者 SU Wenchao TAO Yan ZHANG Xingchun LIU Jianzhong DENG Yiming 《Chinese Journal Of Geochemistry》 EI CAS 2010年第2期157-166,共10页
The Shuiyindong deposit is one of the largest (more than 100 tonnes of Au) and highest grade (more than 7×10-6-10×10-6), strata-bound Carlintype gold deposits in southwestern Guizhou Province, China. The dep... The Shuiyindong deposit is one of the largest (more than 100 tonnes of Au) and highest grade (more than 7×10-6-10×10-6), strata-bound Carlintype gold deposits in southwestern Guizhou Province, China. The deposit is controlled by both structure and favorable lithology. It is situated near the axis of the striking Huijiabao anticline and is hosted in bioclastic limestone of the Permian Longtan Formation. Gold mineralization occurred under low temperature with Th of 220℃± and is closely associated with decarbonation, silicification, sulfidation and dolomitization. The deposit has a characteristic elemental assemblage of Au-As-Hg-Tl. Studies of geochemistry and isotope compositions indicated that the ore-bearing materials and fluids of the gold deposit mainly originated from a plutonic source, and possess a mixing feature with the strata matter during transportation from mantle to crust. Fluid inclusions in vein quartz from the gold deposit are rich in volatile flux, indicating that metallogenic fluid is an overpres-sured one. The activity and geothermal state of the Earth's crust in the long period of time are favorable for the formation of overpressured fluids in a large area, and extensive structures would drive the fluids into ore-forming sys-tem and make gold deposits formed. The complexity of structural movement in the upper crust of southwestern Guizhou Province resulted in complicated gold mineralization. Through metallogenic prognosis and exploration, the proven reserves of the deposit increased by tens of tonnes of Au and the deposit has become a super-large strata-bound Carlin-type gold deposit. 展开更多
关键词 矿床预测 成矿模型 卡林型 超大型 水银洞 西南部 贵州省 层控
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Floquet Bound States in a Driven Two-Particle Bose-Hubbard Model with an Impurity
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作者 钟宏华 周政 +2 位作者 朱博 柯勇贯 李朝红 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期29-32,共4页
We investigate how the driving field affects the bound states in the one-dimensional two-particle Bose-Hubbard model with an impurity. In the high-frequency regime, compared with the static lattice [Phys. Rev. Lett. 1... We investigate how the driving field affects the bound states in the one-dimensional two-particle Bose-Hubbard model with an impurity. In the high-frequency regime, compared with the static lattice [Phys. Rev. Lett. 109 (2012) 116405], a new type of Floquet bound state can be obtained even for a weak particle-particle interaction by tuning the driving amplitude. Moreover, the localization degree of the F1oquet bound molecular state can be adjusted by tuning the driving frequency, and even the Floquet bound molecular state can be changed into the Floquet extended state when the driving frequency is below a critical value. Our results provide an efficient way to manipulate bound states in the many-body systems. 展开更多
关键词 Floquet bound States in a Driven Two-Particle Bose-Hubbard model with an Impurity BIC
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Estimation of Bounded Populations and Carrying Capacity with the Logistic Model
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作者 Lamin Kabareh Thomas Mageto 《Open Journal of Statistics》 2017年第6期936-943,共8页
Estimation of bounded populations and carrying capacity in the presence of a sample frame is considered. Models based on Logistic model are proposed. Like the existing estimators, this estimation technique deals with ... Estimation of bounded populations and carrying capacity in the presence of a sample frame is considered. Models based on Logistic model are proposed. Like the existing estimators, this estimation technique deals with initial condition and is based on yearly population totals in order to fit in a model within a given period of time in this study. The proposed Logistic model technique has shown to be efficient especially with large data. The empirical study indicated that the Logistic model is efficient and can estimate properly even in the presence of outliers. 展开更多
关键词 LOGISTIC model ESTIMATION boundED Population Carrying Capacity SAMPLE Frame Empirical Study and OUTLIERS
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Global Existence of Solutions for Baer-Nunziato Two-Phase Flow Model in a Bounded Domain
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作者 Wenhui Kou 《Open Journal of Applied Sciences》 2022年第4期631-649,共19页
In this paper, we study the global existence and uniqueness of strong solutions for the Baer-Nunziato two-phase flow model in a bounded domain with a no-slip boundary. The global existence and uniqueness of strong sol... In this paper, we study the global existence and uniqueness of strong solutions for the Baer-Nunziato two-phase flow model in a bounded domain with a no-slip boundary. The global existence and uniqueness of strong solutions are obtained when the initial value is near the equilibrium state in H<sup>2</sup> (&#937;). Furthermore, the exponential convergence rates of the pressure and velocity are also proved by delicate energy methods. 展开更多
关键词 Two-Phase model bounded Domain Global Existence Energy Method
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Lower Bounds of Decay Rates for Solution to the Single-Layer Quasi-Geostrophic Model
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作者 Haoyu Zhao 《Journal of Applied Mathematics and Physics》 2023年第8期2221-2230,共10页
In this paper, we study the long-time behavior of solutions of the single-layer quasi-geostrophic model arising from geophysical fluid dynamics. We obtain the lower bound of the decay estimate of the solution. Utilizi... In this paper, we study the long-time behavior of solutions of the single-layer quasi-geostrophic model arising from geophysical fluid dynamics. We obtain the lower bound of the decay estimate of the solution. Utilizing the Fourier splitting method, under suitable assumptions on the initial data, for any multi-index α, we show that the solution Ψ satisfies . 展开更多
关键词 Single-Layer Quasi-Geostrophic model Lower bounds Fourier Splitting Method
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Finite element modeling of acoustic scattering from an encapsulated microbubble near rigid boundary
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作者 黄蓓 张艳丽 +1 位作者 章东 龚秀芬 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期378-383,共6页
This article proposes a finite element model (FEM) for predicting the acoustic scattering from an encapsulated microbubble near rigid boundary. The validity of the model is first examined by comparing the acoustic n... This article proposes a finite element model (FEM) for predicting the acoustic scattering from an encapsulated microbubble near rigid boundary. The validity of the model is first examined by comparing the acoustic nonlinear response of a free microbubble with that obtained by the Church model. Then this model is used to investigate the effect of the rigid boundary on acoustic scattering signals from microbubble. The results indicate that the resonance frequency decreases while the oscillation amplitude increases as the microbubble approaches the rigid boundary. In addition, the fundamental component of the acoustic scattering signal is enhanced compared with that of the free microbubble. 展开更多
关键词 bound encapsulated microbubble acoustic scattering finite element model
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Reliability Bounds based on Universal Generating Function and Discrete Stress-strength Interference Model
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作者 GUO Hui-xin SUO Bin ZHANG Gan-qing 《International Journal of Plant Engineering and Management》 2017年第3期175-187,共13页
A method for estimating the component reliability is proposed when the probability density functions of stress and strength can not be exactly determined. For two groups of finite experimental data about the stress an... A method for estimating the component reliability is proposed when the probability density functions of stress and strength can not be exactly determined. For two groups of finite experimental data about the stress and strength, an interval statistics method is introduced. The processed results are formulated as two interval-valued random variables and are graphically represented component reliability are proposed based on the by using two histograms. The lower and upper bounds of universal generating function method and are calculated by solving two discrete stress-strength interference models. The graphical calculations of the proposed reliability bounds are presented through a numerical example and the confidence of the proposed reliability bounds is discussed to demonstrate the validity of the proposed method. It is showed that the proposed reliability bounds can undoubtedly bracket the real reliability value. The proposed method extends the exciting universal generating function method and can give an interval estimation of component reliability in the case of lake of sufficient experimental data. An application example is given to illustrate the proposed method 展开更多
关键词 universal generating function discrete stress-strength interference model reliability bounds reliability estimation
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A branch-and-bound algorithm for discrete multi-factor portfolio optimization model 被引量:1
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作者 牛淑芬 王国欣 孙小玲 《Journal of Shanghai University(English Edition)》 CAS 2008年第1期26-30,共5页
In this paper, a new branch-and-bound algorithm based on the Lagrangian dual relaxation and continuous relaxation is proposed for discrete multi-factor portfolio selection model with roundlot restriction in financial ... In this paper, a new branch-and-bound algorithm based on the Lagrangian dual relaxation and continuous relaxation is proposed for discrete multi-factor portfolio selection model with roundlot restriction in financial optimization. This discrete portfolio model is of integer quadratic programming problems. The separable structure of the model is investigated by using Lagrangian relaxation and dual search. Computational results show that the algorithm is capable of solving real-world portfolio problems with data from US stock market and randomly generated test problems with up to 120 securities. 展开更多
关键词 portfolio optimization discrete multi-factor model Lagrangian relaxation and continuous relaxation branch-and-bound method.
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超固结黏土的剪胀方程及边界面模型
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作者 徐斌 陈柯好 庞锐 《岩土力学》 北大核心 2025年第2期449-456,466,共9页
超固结黏土的应力-应变特性随超固结程度的演变呈现出较为复杂的力学特性。开发一个实用的本构模型可为超固结黏土的数值分析提供强有力的工具。首先,分析超固结黏土的剪胀特性随超固结程度的变化,将超固结参数引入剪胀关系中,建立形式... 超固结黏土的应力-应变特性随超固结程度的演变呈现出较为复杂的力学特性。开发一个实用的本构模型可为超固结黏土的数值分析提供强有力的工具。首先,分析超固结黏土的剪胀特性随超固结程度的变化,将超固结参数引入剪胀关系中,建立形式简单的超固结黏土剪胀方程,并将其积分为塑性势面。然后,在边界面理论的框架下,结合所提出的剪胀方程,采用简单实用的理论方法,建立超固结黏土的边界面本构模型。最后,采用大范围超固结度下的三轴排水压缩和拉伸、三轴不排水压缩和拉伸试验以及复杂应力路径试验对所提本构模型的性能进行全面验证。结果表明:所提出的模型可以较好地描述超固结黏土的应力-应变特性随超固结程度的变化,并且在体变和孔压模拟方面具有较大的优势。 展开更多
关键词 黏土 超固结 剪胀方程 边界面理论 临界状态
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Two-vibron bound states in the β-Fermi-Pasta-Ulam model
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作者 胡新广 唐翌 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4268-4272,共5页
This paper studies the two-vibron bound states in the β- Fermi Pasta-Ulam model by means of the number conserving approximation combined with the number state method. The results indicate that on-site, adjacent-site ... This paper studies the two-vibron bound states in the β- Fermi Pasta-Ulam model by means of the number conserving approximation combined with the number state method. The results indicate that on-site, adjacent-site and mixed two-vibron bound states may exist in the model. Specially, wave number has a significant effect on such bound states, which may be considered as the quantum effects of the localized states in quantum systems. 展开更多
关键词 discrete breathers Fermi-Pasta-Ulam model number state method two-vibron bound states
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波流共同作用下砂质海床液化分析
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作者 薛莹莹 张杰 +2 位作者 陈炜昀 张璟哲 蔡飞 《哈尔滨工程大学学报》 北大核心 2025年第7期1317-1324,共8页
针对潮流对海床液化前和液化后海床位移特征的影响规律尚不明确问题,本文建立了一个波流共同作用下多孔弹塑性海床有限元模型,采用Biot控制方程描述海床动力响应,采用状态相关的边界面模型模拟海床液化行为。计算结果表明:潮流不仅影响... 针对潮流对海床液化前和液化后海床位移特征的影响规律尚不明确问题,本文建立了一个波流共同作用下多孔弹塑性海床有限元模型,采用Biot控制方程描述海床动力响应,采用状态相关的边界面模型模拟海床液化行为。计算结果表明:潮流不仅影响海床内部的累积孔压,对海床内振荡孔压也有较大影响;波流对砂质海床的密实作用在海床液化后尤为显著。当海床液化后,同向波流总体能够增大海床的位移,尤其是水平位移,而逆向波流显著降低海床水平位移。砂质海床竖向位移随着波流的持续作用,经历了3个典型阶段,即弹性响应阶段、逐渐压密阶段、严重液化阶段。 展开更多
关键词 波流共同作用 海床液化 饱和多孔弹塑性海床 u-p形式Biot理论 海床位移轨迹 海床孔压累积 有限元分析 边界面模型
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概率约束下基于观测器的高效模型预测控制
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作者 宋燕 张奕淳 《控制与决策》 北大核心 2025年第5期1669-1676,共8页
提出一种随机模型预测控制(SMPC)算法,适用于具有有界加性噪声和不完整状态信息的线性离散时间系统.首先,假设噪声的一阶矩和二阶矩已知,利用Chebyshev-Cantelli不等式将施加在状态和输入上的概率约束重新表述为确定性形式;然后,在高效... 提出一种随机模型预测控制(SMPC)算法,适用于具有有界加性噪声和不完整状态信息的线性离散时间系统.首先,假设噪声的一阶矩和二阶矩已知,利用Chebyshev-Cantelli不等式将施加在状态和输入上的概率约束重新表述为确定性形式;然后,在高效模型预测控制(EMPC)的框架下设计基于观测器的输出反馈控制器;接着,引入附加的摄动量,采用“离线计算、在线综合”的方法最大化初始可行域并计算控制律;最后,给出一个平均渐近性能指标的上界,验证所提出算法的递推可行性.仿真结果表明了所提出算法的有效性. 展开更多
关键词 随机模型预测控制 有界噪声 概率约束 输出反馈 初始可行域
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水下机械手柔顺操作模型参考自适应阻抗控制研究
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作者 李沙沙 夏满江 张建军 《控制与信息技术》 2025年第2期38-44,共7页
针对水下机械手在多样化操作任务中因关节摩擦与测量不精确导致的模型不确定性问题,文章提出了一种模型参考自适应阻抗控制方法,以提高系统的鲁棒性与操作稳定性。首先,设计了基于标准力与操作力误差的期望阻抗模型,并根据操作空间位置... 针对水下机械手在多样化操作任务中因关节摩擦与测量不精确导致的模型不确定性问题,文章提出了一种模型参考自适应阻抗控制方法,以提高系统的鲁棒性与操作稳定性。首先,设计了基于标准力与操作力误差的期望阻抗模型,并根据操作空间位置与阻抗模型输出期望位置设计了自适应律及“有界-增益-遗忘”自适应更新策略,实现了机械手末端操作力对标准力信号的精确跟踪;随后,通过设计李雅普诺夫函数证明了系统的全局稳定性以及力和位置的跟踪性能;最后,在Matlab/Simulink平台上进行了二自由度机械手的仿真实验。实验结果表明,所设计的控制器具有良好的自适应性能和鲁棒性,确保了力和位置跟踪的优异性能。 展开更多
关键词 水下机械手 阻抗控制 参考模型 自适应律 有界-增益-遗忘
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基于有限理性决策模型的大型建筑群体空间布局模式优化设计研究
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作者 刘畅 景泉 《世界建筑》 2025年第11期108-115,共8页
本研究探究“有限理性决策模型”在大型建筑群体空间布局优化设计中的正向影响与应用,以期在设计策划阶段通过“系统动态调节—负反馈调节”双循环设计逻辑获得满意解。同时,结合分期实施、可完成多轮布局优化的典型案例,借助量化分析方... 本研究探究“有限理性决策模型”在大型建筑群体空间布局优化设计中的正向影响与应用,以期在设计策划阶段通过“系统动态调节—负反馈调节”双循环设计逻辑获得满意解。同时,结合分期实施、可完成多轮布局优化的典型案例,借助量化分析方法,通过“本底分析—方案生成—成果模拟”的正循环及“成效评估—建议汇总—模式优化”的负循环,形成动态反馈的布局优化策略并完成应用示范。 展开更多
关键词 大型建筑群体空间 空间布局 有限理性决策模型 双循环设计逻辑 优化策略 应用示范
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基于有限理性理论的公交服务满意度评价研究
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作者 张兵 邢宇 +1 位作者 胡启洲 薛运强 《重庆交通大学学报(自然科学版)》 北大核心 2025年第6期73-81,共9页
为真实反映公交服务水平,改善服务质量,提高乘客满意度,根据当前乘客满意度研究存在的主要不足,分析了有限理性视野下乘客满意度研究的适用条件,说明考虑乘客有限理性因素对满意度研究的必要性;并在常规满意度评价模型的基础上,增加了... 为真实反映公交服务水平,改善服务质量,提高乘客满意度,根据当前乘客满意度研究存在的主要不足,分析了有限理性视野下乘客满意度研究的适用条件,说明考虑乘客有限理性因素对满意度研究的必要性;并在常规满意度评价模型的基础上,增加了反映乘客有限理性因素的潜变量“乘客认知”和“态度偏好”,建立了“基于有限理性的公交服务满意度”偏最小二乘法结构方程测评模型。以南昌市公交乘客问卷数据进行满意度评价,并根据有限理性因素修正满意度得分,依据乘客特性进行分群研究,运用重要性-绩效分析法(IPA)得到针对不同群体的改善策略。研究结果显示:乘客认知与态度偏好均对满意度有显著影响,表明乘客有限理性因素会影响满意度的评价结果;感知价值与感知质量同样是影响满意度的重要因素;计算修正后的乘客满意度得分为68.0%,整体满意度偏低,需优先改进信息服务、便捷性、安全性、社会保障等方面,以提升公交服务满意度。 展开更多
关键词 交通运输工程 乘客满意度 有限理性 偏最小二乘法结构方程模型 公交乘客
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一种用于Mecanum底盘的自适应路径规划算法 被引量:1
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作者 黄晓宇 孙勇智 +2 位作者 李津蓉 刘薇 李恒通 《机械科学与技术》 北大核心 2025年第3期530-537,共8页
为解决狭小且复杂工作环境下,麦克纳姆轮自动导引车(Automated guided vehicle,AGV)最优路径规划问题,提出了一种基于麦克纳姆轮底盘运动学模型改进的A^(*)算法。首先,将麦克纳姆轮AGV等效为二维最小外接矩形,利用其全向移动特性设计路... 为解决狭小且复杂工作环境下,麦克纳姆轮自动导引车(Automated guided vehicle,AGV)最优路径规划问题,提出了一种基于麦克纳姆轮底盘运动学模型改进的A^(*)算法。首先,将麦克纳姆轮AGV等效为二维最小外接矩形,利用其全向移动特性设计路径搜索策略;其次为提高规划路径的安全性,依据模型特征构建了拓展模型避障矩阵;最后引入二维高斯核函数自适应调整算法实际代价函数和启发估计代价函数的权重系数,平衡搜索的全局性和快速性。仿真试验结果表明:改进的算法在搜索时间和安全性能均高于普通算法,提高了麦克纳姆轮AGV通过狭窄空间或转弯死角的能力,增强了路径搜索效率。 展开更多
关键词 麦克纳姆轮 A^(*)算法 外接矩形 拓展模型避障矩阵 二维高斯核函数
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面向SAR图像任意方向舰船检测的改进YOLOv5
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作者 曲春辉 王玮 +2 位作者 张婷 王英华 陈渤 《西安电子科技大学学报》 北大核心 2025年第4期1-14,共14页
合成孔径雷达(SAR)图像舰船检测方法面临舰船多尺度、任意方向、密集排列等难题,旋转框检测方法能实现任意方向舰船的精确检测,但是现有旋转框检测方法难以兼顾高精度与实时性。为解决上述问题,提出了一个结合中点偏移量表示法和YOLOv5... 合成孔径雷达(SAR)图像舰船检测方法面临舰船多尺度、任意方向、密集排列等难题,旋转框检测方法能实现任意方向舰船的精确检测,但是现有旋转框检测方法难以兼顾高精度与实时性。为解决上述问题,提出了一个结合中点偏移量表示法和YOLOv5的旋转框检测网络模型,直接继承水平框的回归机制,并设计适应于旋转检测的多任务联合网络损失函数,解决了常用旋转框检测表示方法引入角度参数而产生的网络难以训练和网络预测层参数冗余的问题。此外,还提出了基于注意力机制的主干网络,结合图像全局和邻域信息,增强了感兴趣区域的重要性和模型的特征提取能力,提高了轻量化旋转框检测网络的性能。最后,在RSDD-SAR数据集上进行实验,实现了SAR图像任意方向舰船目标检测,并获得舰船相应的角度信息,相比当前其他旋转框检测方法,取得了较好的检测效果,平均精度为90.02%。尤其在复杂近岸场景下所提方法达到了最优的舰船目标检测性能,平均精度为70.5%,并且模型的参数量最少,仅为7.2 M。其他相关实验也进一步验证了所提方法的有效性。 展开更多
关键词 合成孔径雷达 舰船 目标检测 旋转框 YOLOv5模型
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