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Activin A enhances neurofunctional recovery following traumatic spinal cord injury by inhibiting autophagy
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作者 Liqun Yu Zhaoyang Yin +12 位作者 Ruiqi Huang Zhibo Liu Yuchen Liu Xinxin Zheng Simin Song Zhaojie Wang Xiaolie He Yuxin Bai Li Yang Xu Xu Bairu Chen Jian Yin Yanjing Zhu 《Neural Regeneration Research》 2026年第6期2485-2494,共10页
In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neur... In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neurofunctional recovery.Activin A is a critical growth factor necessary for the development of the embryonic nervous system and for maintaining neuronal function in the adult cerebral cortex.It can inhibit excessive autophagy in ischemic stroke to reduce neuronal damage.However,the specific mechanism through which Activin A functions in the spinal cord remains poorly understood.In this study,we administered different concentrations of Activin A to neural stem cells from the spinal cord and found that Activin A stimulated the proliferation and neuronal differentiation of neural stem cells.Then,we established an in vitro oxidative stress model by using hydrogen peroxide to stimulate the neural stem cells-induced neurons.We found that Activin A could reduce apoptosis caused by oxidative stress.Subsequently,we treated a mouse model of spinal cord contusion with intrathecal injection of Activin A.Behavioral and electrophysiological results showed that Activin A promoted recovery of motor function and reconstruction of neural circuits in the model mice.Finally,RNA sequencing indicated that Activin A inhibited autophagy by activating the PI3K/AKT/mTOR pathway and upregulating the expression of synaptogenesis-related factor Sema3A in the spinal cord.These results suggest that Activin A may mediate the excessive autophagic response after spinal cord injury,promote the reconstruction of damaged neural circuits,and restore neurological function in the injured spinal cord. 展开更多
关键词 Activin A AUTOPHAGY cell differentiation motor function recovery neural regeneration neural stem cell NEUROPROTECTION phosphoinositide 3-kinase/protein kinase b pathway spinal cord injury transforming growth factor-βsuperfamily
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Generalized spline adaptive filtering algorithm based on q-hyperbolic function
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作者 Shiwei Yun Sihai Guan +1 位作者 Chuanwu Zhang Bharat Biswal 《Journal of Automation and Intelligence》 2025年第2期125-135,共11页
Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic fu... Based on the superiority of adaptive filtering algorithms designed with hyperbolic function-like objective functions,this paper proposes generalized spline adaptive filtering(SAF)algorithms designed with hyperbolic function-like objective functions.Specifically,a series of generalized new SAF algorithms are proposed by introducing the q-deformed hyperbolic function as the cost function,named SAF-qDHSI,SAF-qDHCO,SAFqDHTA&SAF-qDHSE algorithms,respectively.Then,the proposed algorithm is theoretically demonstrated with detailed mean convergence and computational complexity analysis;secondly,the effect of different q values on the performance of the new algorithm is verified through data simulation;the new algorithm still has better performance under the interference of Gaussian noise and non-Gaussian noise even when facing the system mutation;finally,the new algorithm is verified through the measured engineering data,and the results show that the new algorithm has better convergence and robustness compared with the existing algorithm.In conclusion,the generalized algorithm based on the new cost function proposed in this paper is more effective in nonlinear system identification. 展开更多
关键词 Nonlinear systems spline adaptive filtering q-deformed hyperbolic functions
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基于三次B样条的机器人自动焊接轨迹规划方法
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作者 晏祖根 翟一帆 +4 位作者 杨旭辉 付斌 吕绪超 杨鸿阳 吕志超 《哈尔滨商业大学学报(自然科学版)》 2026年第1期83-91,共9页
针对机器人难以对食品高压釜端盖曲面自动焊接的问题,采用三次B样条插补法对焊接机器人关节空间进行焊接轨迹规划.利用自动焊接系统中的线激光相机对焊缝采样,提取焊接运动过程中的控制点,在Matlab中对焊接路径以及机器人各关节位移、... 针对机器人难以对食品高压釜端盖曲面自动焊接的问题,采用三次B样条插补法对焊接机器人关节空间进行焊接轨迹规划.利用自动焊接系统中的线激光相机对焊缝采样,提取焊接运动过程中的控制点,在Matlab中对焊接路径以及机器人各关节位移、速度、加速度进行仿真实验.结果表明,机器人能运行在预期的焊接轨迹上,且各关节在运动过程中速度、加速度曲线平滑.利用ROBOGUIDE对焊接高压釜端盖的过程进行仿真,仿真过程中机器人以理想的姿态运行在预期的轨迹上,运动过程平稳.结果表明三次B样条函数在关节空间进行插值可以得到平滑的运动轨迹,实际运动轨迹与理想轨迹位置偏离误差控制在0.2 mm以内,可实现机器人对高压釜端盖曲面的自动焊接. 展开更多
关键词 焊接机器人 自动焊接 b样条 关节空间 焊接轨迹规划 食品高压釜
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Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury 被引量:3
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作者 Ziwei Fan Mengxian Jia +16 位作者 Jian Zhou Zhoule Zhu Yumin Wu Xiaowu Lin Yiming Qian Jiashu Lian Xin Hua Jianhong Dong Zheyu Fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu Zhu Ying Wang Zhihui Huang Honglin Teng 《Neural Regeneration Research》 SCIE CAS 2025年第11期3287-3301,共15页
The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury.Regulation of shifting microglia ... The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury.Regulation of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be crucial.Tryptanthrin possesses an anti-inflammatory biological function.However,its roles and the underlying molecular mechanisms in spinal cord injury remain unknown.In this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in vitro.Tryptanthrin promoted M2 polarization through inactivating the cGAS/STING/NF-κB pathway.Additionally,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord injury.Finally,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal apoptosis.Taken together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype. 展开更多
关键词 cGAS/STING functional recovery MICROGLIA neuroinflammation neuroprotection nuclear factor-κb POLARIZATION spinal cord injury TRYPTANTHRIN
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A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics 被引量:7
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作者 C.A.Rabbath D.Corriveau 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期741-757,共17页
Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and repr... Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile. 展开更多
关键词 Aerodynamic coefficients PIECEWISE POLYNOMIAL functionS CUbIC splines Curve fitting PIECEWISE linear functionS PIECEWISE CUbIC HERMITE interpolating POLYNOMIAL PROJECTILE modelling and simulation Fire control inputs Precision ballistic computer software
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Numerical Solution of Functional Integral and Integro-Differential Equations by Using B-Splines 被引量:1
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作者 Hesam-Eldien Derili Gherjalar Hossein Mohammadikia 《Applied Mathematics》 2012年第12期1940-1944,共5页
This paper describes an approximating solution, based on Lagrange interpolation and spline functions, to treat functional integral equations of Fredholm type and Volterra type. This method extended to functional integ... This paper describes an approximating solution, based on Lagrange interpolation and spline functions, to treat functional integral equations of Fredholm type and Volterra type. This method extended to functional integral and integro-differential equations. For showing efficiency of the method we give some numerical examples. 展开更多
关键词 LAGRANGE Interpolation b-spline functions functionAL Integral EQUATION functionAL Integro-Differential EQUATION functionAL Differential EQUATION
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多策略协同扩展的变步长CDBA-RRT^(∗)机器人路径规划算法
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作者 韩龙岗 盛洲 徐浩 《计算机应用研究》 北大核心 2026年第2期411-419,共9页
针对传统RRT^(∗)算法在进行路径规划时存在效率低下以及路径质量不高等问题,提出一种改进算法CDBA-RRT^(∗)(cooperative dynamic Bi-APF-RRT^(∗))。该方法维护两棵双向搜索树并采用多策略协同扩展。首先构建长轴固定、短轴随迭代次数动... 针对传统RRT^(∗)算法在进行路径规划时存在效率低下以及路径质量不高等问题,提出一种改进算法CDBA-RRT^(∗)(cooperative dynamic Bi-APF-RRT^(∗))。该方法维护两棵双向搜索树并采用多策略协同扩展。首先构建长轴固定、短轴随迭代次数动态增大的椭圆采样区域以及采用密度自适应的动态目标偏置策略控制采样点的选取;其次设计目标距离权重衰减函数与节点斥力场解决经典APF因固定引力权重导致的目标迷失及局部聚集瘫痪等问题;此外采用自适应动态扩展步长;最后分段使用三次B样条插值法对路径进行平滑以满足机器人运动学约束。在三种标准化环境以及两种高约束环境中对算法进行仿真实验,实验结果表明,CDBA-RRT^(∗)在时间耗费、搜索节点数以及路径质量等方面均优于其他五种RRT^(∗)算法,具有较高可行性。 展开更多
关键词 路径规划 CDbA-RRT^(∗) 协同扩展 动态目标偏置 密度自适应 权重函数 三次b样条插值
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Hepatitis B functional cure:Current and future perspective 被引量:1
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作者 Sudheer Marrapu Jinit R Soni +1 位作者 Kislaya Kamal Ramesh Kumar 《World Journal of Hepatology》 2025年第10期109-124,共16页
Chronic hepatitis B(CHB)remains a significant global health challenge,affecting more than 250 million individuals worldwide.A functional cure,defined as the loss of hepatitis B surface antigen(HBsAg)and suppression of... Chronic hepatitis B(CHB)remains a significant global health challenge,affecting more than 250 million individuals worldwide.A functional cure,defined as the loss of hepatitis B surface antigen(HBsAg)and suppression of hepatitis B virus(HBV)DNA to undetectable levels,represents the optimal therapeutic endpoint for managing CHB.However,the complex pathogenesis of CHB,which includes HBV DNA integration,persistence of covalently closed circular DNA,and impaired immune responses,presents substantial barriers to HBsAg clearance.Current therapies offer limited success in achieving a functional cure,with HBsAg seroclearance occurring in only 3%-5%of patients after 10 years of nucleos(t)ide analogs(NAs)therapy and 8%-14%within 3-5 years of pegylated interferon treatment.To overcome these limitations,novel direct-acting antivirals targeting different stages of the HBV life cycle are being investigated.Additionally,immunomodulatory approaches,including therapeutic vaccines and immune checkpoint inhibitors,are being explored to enhance HBV-specific immune responses.The concept of NAs cessation in carefully selected non-cirrhotic patients may accelerate HBsAg loss,although the risks of hepatic flare and hepatocellular carcinoma necessitate rigorous monitoring.This review provides a comprehensive overview of the current understanding of HBsAg seroclearance in CHB,discussing its clinical significance,therapeutic challenges,and evolving treatment landscape in the pursuit of a functional cure. 展开更多
关键词 Hepatitis b Hepatitis b surface antigen seroclearance functional cure Surface antigen Virological cure
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An Adaptive Median Filter Algorithm Based on B-spline Function 被引量:11
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作者 Mei-Sen Pan Jing-Tian Tang Xiao-Li Yang 《International Journal of Automation and computing》 EI 2011年第1期92-99,共8页
According to the B-spline convolution mask, first, the contrast sensitiveness (CS) is computed and then is viewed as a noise sensitiveness coeficient (NSC) to adaptively determine a noise-recognized threshold valu... According to the B-spline convolution mask, first, the contrast sensitiveness (CS) is computed and then is viewed as a noise sensitiveness coeficient (NSC) to adaptively determine a noise-recognized threshold value. Based on the noise density function (NDF) in a 3×3 window, the filtering window size is adaptively adjusted, and then a median filter is used to eliminate the noise-marked pixels. The experiment results show that the proposed algorithm can preserve image detail information well and effectively remove the noises, particularly the impulse noises that is also called salt-and-pepper noises superimposed on the computed tomography (CT) and magnetic resonance imaging (MRI) medical images. 展开更多
关键词 Salt-and-pepper noise median filter human vision system b-spline.
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基于B样条曲面的N边孔洞填补算法
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作者 张军锋 童若锋 +1 位作者 唐敏 李海龙 《浙江大学学报(理学版)》 北大核心 2026年第2期222-231,共10页
在实际工程应用中,对边界扭曲、兼容性较差的N边孔洞,现有的填补算法无法实现G^(1),G^(2)连续,仅能实现G^(0)连续,且当区域狭长时可能出现内部不光顺现象。对此,提出了视觉连续性概念,用拼接处的法向角度差衡量G^(1)连续的程度,并通过... 在实际工程应用中,对边界扭曲、兼容性较差的N边孔洞,现有的填补算法无法实现G^(1),G^(2)连续,仅能实现G^(0)连续,且当区域狭长时可能出现内部不光顺现象。对此,提出了视觉连续性概念,用拼接处的法向角度差衡量G^(1)连续的程度,并通过插入节点和调整控制点生成视觉连续的N边补洞,本文算法不仅在等照度线上的效果优于传统算法及商用引擎Parasolid,而且生成效率得到大幅提升。 展开更多
关键词 b样条曲面 N边孔洞 几何连续 视觉连续
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4阶NUAT-B样条曲线的几何形状
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作者 陈海伟 沈莞蔷 胡清元 《浙江大学学报(理学版)》 北大核心 2026年第2期263-274,284,共13页
为探究样条表示与几何表示之间的关系,考虑4阶非均匀代数三角B(NUAT-B)样条曲线的几何形状。将NUAT-B样条基函数分离为代数多项式样条和三角多项式样条两部分,分别推导每一部分的几何特征,得到任意一条可描述一个点的轨迹的4阶NUAT-B样... 为探究样条表示与几何表示之间的关系,考虑4阶非均匀代数三角B(NUAT-B)样条曲线的几何形状。将NUAT-B样条基函数分离为代数多项式样条和三角多项式样条两部分,分别推导每一部分的几何特征,得到任意一条可描述一个点的轨迹的4阶NUAT-B样条曲线,该点沿着一系列椭圆轨道绕椭圆中心旋转,同时椭圆中心沿着一系列直线平移,椭圆和直线在样条的参数节点处发生变化。并且,给出这些直线的端点、椭圆的长短半轴和焦点关于样条曲线控制顶点的显式表达。进一步,设计了NUAT-B样条形式与几何形式的相互转换算法,并用实验检验算法的正确性。实验结果表明,圆柱螺线和摆线可通过圆半径等几何特征精确调节控制顶点,实时改变几何形状。 展开更多
关键词 计算机辅助几何设计(CAGD) NUAT-b样条曲线 b样条曲线 椭圆 轨迹
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B样条曲线驱动的脊形乘波体设计与气动分析
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作者 熊佳俊 徐大军 曹沥丹 《弹箭与制导学报》 北大核心 2026年第1期1-10,共10页
传统脊形乘波体设计中,设计型线参数调整复杂且设计直观性欠佳。为此,本文提出基于B样条曲线的脊形上表面设计方法,通过控制点直接调整设计型线,提升设计灵活性与便捷性。利用Bezier曲线构建底部型线,结合吻切锥理论确定前缘与下表面底... 传统脊形乘波体设计中,设计型线参数调整复杂且设计直观性欠佳。为此,本文提出基于B样条曲线的脊形上表面设计方法,通过控制点直接调整设计型线,提升设计灵活性与便捷性。利用Bezier曲线构建底部型线,结合吻切锥理论确定前缘与下表面底部型线,采用三次和二次B样条曲线构建上表面型线。通过CFD(Computational Fluid Dynamics)方法验证方法可靠性,分析脊形乘波体的气动性能。结果表明:随着攻角逐渐增大,脊形上表面对气动特性的影响逐渐减弱,最大升阻比出现在攻角4°至6°范围内。所提方法为乘波体设计提供了更直观的型线优化手段,对工程化设计具有参考价值。 展开更多
关键词 乘波体 b样条曲线 脊形体 高超声速
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元素掺杂及分子吸附对B4C3电子性质的影响
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作者 李萱 邵立 +2 位作者 门彩瑞 何渊淘 李艳 《吉林大学学报(理学版)》 北大核心 2026年第1期158-165,共8页
研究S,N,P,Si 4种原子掺杂和NO,NO_(2),NH_(3),CO,CO_(2),SO_(2),H_(2)S 7种小分子吸附对B_(4)C_(3)二维材料几何结构和电子性质的影响.结果表明,与本征B_(4)C_(3)材料2.020 eV带隙相比,掺杂和小分子吸附体系的禁带宽度均减小.其中,N掺... 研究S,N,P,Si 4种原子掺杂和NO,NO_(2),NH_(3),CO,CO_(2),SO_(2),H_(2)S 7种小分子吸附对B_(4)C_(3)二维材料几何结构和电子性质的影响.结果表明,与本征B_(4)C_(3)材料2.020 eV带隙相比,掺杂和小分子吸附体系的禁带宽度均减小.其中,N掺杂体系的带隙值在4种体系中最小,因此掺杂N原子对B_(4)C_(3)的电子性质影响最明显. NO_(2)吸附后B_(4)C_(3)由半导体变为金属,表明B_(4)C_(3)可有效检测NO_(2)气体. 展开更多
关键词 密度泛函理论 二维b4C3 掺杂 吸附
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Solutions of Seventh Order Boundary Value Problems Using Ninth Degree Spline Functions and Comparison with Eighth Degree Spline Solutions 被引量:1
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作者 Parcha Kalyani Mihretu Nigatu Lemma 《Journal of Applied Mathematics and Physics》 2016年第2期249-261,共13页
In this article, we develop numerical method by constructing ninth degree spline function using extended cubic spline Bickley’s method to find the approximate solution of seventh order linear boundary value problems ... In this article, we develop numerical method by constructing ninth degree spline function using extended cubic spline Bickley’s method to find the approximate solution of seventh order linear boundary value problems at different step lengths. The approximate solution is compared with the solution obtained by eighth degree splines and exact solution. It has been observed that the approximate solution is an excellent agreement with exact solution. Low absolute error indicates that our numerical method is effective for solving high order linear boundary value problems. 展开更多
关键词 Seventh Order boundary Value Problem boundary Value Problem Ninth Degree spline function Absolute Error
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基于改进黏菌算法与B样条曲线拟合的采煤机过断层截割路径优化方法
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作者 何珍亮 刘宗君 刘万里 《工矿自动化》 北大核心 2026年第3期185-192,共8页
传统采煤机截割路径优化方法在面对断层起伏变化大煤层时适应性较差,难以保障截割路径的连续性与稳定性。针对上述问题,提出了一种基于改进黏菌算法与B样条曲线拟合的采煤机过断层截割路径优化方法。首先,根据煤层地质模型获取断层特征... 传统采煤机截割路径优化方法在面对断层起伏变化大煤层时适应性较差,难以保障截割路径的连续性与稳定性。针对上述问题,提出了一种基于改进黏菌算法与B样条曲线拟合的采煤机过断层截割路径优化方法。首先,根据煤层地质模型获取断层特征信息,并结合B样条曲线规划出采煤机过断层截割轨迹控制点;然后,以采煤机截割轨迹与煤岩界面曲线之间的方差最小化为优化目标,利用引入人工蜂群搜索和邻域搜索策略的改进黏菌算法对B样条曲线规划的截割轨迹控制点进行优化,获取采煤机截割轨迹控制点的最佳权值和阈值;最后,结合过断层割岩率、路径平滑性、截割轨迹端点等约束条件进行B样条曲线光滑拟合,获得采煤机过断层最优截割路径。实验结果表明,与B样条-粒子群和B样条-蜉蝣方法相比,所提方法的截割路径优化结果在整体上能更好地接近实际煤岩界面,且均方根误差(RMSE)分别降低了46.87%和42.05%,决定系数(R^(2))分别提升了95.24%和60.78%,截割路径优化精度更高。 展开更多
关键词 采煤机 断层 截割路径 改进黏菌算法 b样条曲线拟合
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基于改进A^(*)算法与B样条曲线的果园履带机路径规划
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作者 陈天嘉 吴春笃 陈立邦 《农机化研究》 北大核心 2026年第8期129-136,共8页
针对传统A^(*)算法在果园履带机路径规划中存在的路径急转弯多、曲率不连续、路径紧贴障碍物等问题,提出了一种改进A^(*)算法与B样条曲线拟合算法相结合的路径规划方法。通过引入动态权重调控策略、方向性约束和曲率代价项,优化传统A^(*... 针对传统A^(*)算法在果园履带机路径规划中存在的路径急转弯多、曲率不连续、路径紧贴障碍物等问题,提出了一种改进A^(*)算法与B样条曲线拟合算法相结合的路径规划方法。通过引入动态权重调控策略、方向性约束和曲率代价项,优化传统A^(*)算法的路径搜索效率和路径质量。同时,采用B样条曲线拟合算法对初始路径进行平滑优化,生成满足履带机运动学约束的连续路径。仿真试验分别在无膨胀层与有膨胀层果园环境下进行,结果表明:与传统A^(*)算法相比,改进算法在无膨胀条件下,路径搜索时间缩短46.35%,迭代次数减少25%,评估节点数减少39.70%;在有膨胀条件下,路径最大曲率降低33.82%,平均曲率降低64.15%,路径更加平滑且避障效果显著。本文方法有效提升了果园履带机的路径规划效率和质量,满足果园复杂环境下的作业需求。 展开更多
关键词 果园履带机 路径规划 改进A^(*)算法 b样条曲线 曲率约束
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Analysis of Stability and Large Deflection Buckle of Rolled Strip by Third Power B-Spline Function Method
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作者 Bian Yuhong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1997年第2期24-28,共5页
A new method——the third power B-spline function method is developed to analyse the stability and the buckle of rolled strip under residual stress.The large deflection theory of thin plate is used to calculate the bu... A new method——the third power B-spline function method is developed to analyse the stability and the buckle of rolled strip under residual stress.The large deflection theory of thin plate is used to calculate the buckle of rolled strip and criterion of critical buckle is given.The computed results tally with those of experiment well,which provides theoretical basis and method for developing the mathematical model of flatness control. 展开更多
关键词 flatness control large deflection buckle critical buckle third power b-spline function
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CHARACTERISTIC THEOREMS OF TH ENATURAL TCHEBYSHEFF SPLINE FUNCTION
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作者 姜至本 王成伟 《Journal of China Textile University(English Edition)》 EI CAS 1993年第2期63-70,共8页
In this paper,we give four characteristic theorems of the natural Tchebysheff splint functionassociated with multiple knots.These theorems possess specific form,that arc convenient forapplicaton;In the case of with si... In this paper,we give four characteristic theorems of the natural Tchebysheff splint functionassociated with multiple knots.These theorems possess specific form,that arc convenient forapplicaton;In the case of with simple knots or polynomial splint,the corollaries of this paper’s the-orems give corresponding results. 展开更多
关键词 GENERATING functionS Greens functionS EXTENDED complete Tchebysheff system EXTENDED differential operator Tchebysheff spline function natural Tchebysheffspline function
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Applying the Radial Basis Function Method to Estimate the Distribution of Total Suspended Matter Concentration in Hangzhou Bay
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作者 CHEN Wanqian GAO Jinpeng +5 位作者 XU Minjie LIU Zezheng LI Bingtian LV Jing LI Shujiang SUN Junchuan 《Journal of Ocean University of China》 2025年第3期557-568,共12页
Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of thes... Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of these missing data is highly valuable for engineering and scientific research.In this study,the radial basis function(RBF)method is used to estimate the spatial distribution of total suspended matter(TSM)concentration in Hangzhou Bay using remote sensing data with severe data gaps.The estimation precision is validated by comparing the results with those of other commonly used interpolation methods,such as the Kriging method and the basic spline(B-spline)method.In addition,the applicability of the RBF method is explored.Results show that the estimation of the RBF method is significantly close to the observation in Hangzhou Bay.The average of the mean absolute error,mean relative error,and root mean square error in all the experiments is evidently smaller than those of the Kriging and B-spline interpolations,indicating that the proposed method is more appropriate for estimating the spatial distribution of the TSM in Hangzhou Bay.Finally,the TSM distribution in the blank observational area is predicted.This study can provide some reference values for handling watercolor remote sensing data. 展开更多
关键词 ocean remote sensing satellite total suspended matter concentration INTERPOLATION radial basis function Kriging method basic spline method
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Association of serum hepatitis B surface antigen with hepatitis B virus DNA and hepatic function in patients with chronic hepatitis B
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作者 Jie Li Meng Li +4 位作者 Hui Sun Yan-Ting Yu Yu-Hang Zhou Fei Fu Lei Yan 《World Journal of Gastrointestinal Surgery》 2025年第10期98-106,共9页
BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)concentrations,hepatitis B virus(HBV)DNA levels,and hepatic function in individuals with chronic hepatitis B(CHB)remains incompletely characterized... BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)concentrations,hepatitis B virus(HBV)DNA levels,and hepatic function in individuals with chronic hepatitis B(CHB)remains incompletely characterized.AIM To examine the association of serum HBsAg concentrations with HBV DNA levels and hepatic function parameters in patients with CHB.METHODS A total of 110 individuals with CHB admitted to Kunming Third People’s Hospital between January 2023 and January 2025 were enrolled as the observation group,whereas 70 age-and sex-matched healthy individuals served as the control group.Fasting peripheral venous blood(5 mL)was collected from all participants.Serum HBsAg and HBV DNA levels(in the observation group),along with hepatic function markers,including total bilirubin(TBIL),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were measured in both groups.Pearson correlation analysis was used to assess the association between serum HBsAg levels and HBV DNA,TBIL,AST,and ALT levels in patients with CHB.Receiver operating characteristic(ROC)curve analysis was conducted to determine optimal cutoff values of HBsAg for predicting high viral load(HBV DNA≥10^(5) IU/mL)and significant liver injury(ALT≥2×upper limit of normal[ULN]).RESULTS HBsAg levels differed significantly across CHB phases:Immune tolerance(IT)phase(4.62±1.51 lgIU/mL),immune clearance(IC)phase(3.84±1.16 lgIU/mL),low replication(LR)phase(2.99±0.66 lgIU/mL),and HBV e antigen-negative hepatitis(ENH)phase(3.40±0.69 lgIU/mL).Corresponding HBV DNA levels were highest in the IT phase(7.41±1.83 log copies/mL),followed by the IC phase(6.03±1.92 log copies/mL),ENH phase(3.89±1.23 log copies/mL),and LR phase(2.55±1.00 log copies/mL).All hepatic function parameters in patients with CHB were significantly elevated compared to the healthy controls.Pearson correlation analysis showed significant positive associations between serum HBsAg levels and HBV DNA,TBIL,AST,and ALT levels.ROC analysis revealed that an HBsAg cutoff>4.09 lgIU/mL predicted HBV DNA≥105 IU/mL(high viral load)with 88.57%sensitivity,78.67%specificity,and an area under the curve(AUC)of 0.868(P<0.001),while a cutoff>4.07 lgIU/mL predicted ALT≥2×ULN(significant liver injury)with 69.70%sensitivity,90.91%specificity,and an AUC of 0.821(P<0.001).CONCLUSION Serum HBsAg,a noninvasive serological marker,holds significant clinical value in CHB management by aiding in the stratification of viral burden and the prediction of hepatic impairment. 展开更多
关键词 Chronic hepatitis b Hepatitis b surface antigen Hepatitis b virus DNA Hepatic function
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