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Asymptotic Behaviors of Hankel Determinants Whose Entries Involve Regularly- or Rapidly-Varying Functions. Part II*
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作者 Antonio Granata 《Advances in Pure Mathematics》 2025年第2期119-144,共26页
Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the la... Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the last results in the paper highlight analogies between algebraic identities for Hankelians with special entries and asymptotic relations valid for large classes of entries. 展开更多
关键词 Asymptotic Behaviors of Hankel Determinants Asymptotic Expansions in the real Domain Regularly- Rapidly- and Exponentially-Varying functions of Higher Order Algebraic Identities for Hankelians
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On a special type of Ma-Minda function
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作者 S.Sivaprasad Kumar Shagun Banga 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第4期654-673,共20页
We introduce a primitive class of analytic functions, by specializing in many wellknown classes, classify Ma-Minda functions based on its conditions and their interesting geometrical aspects. Further, study a newly de... We introduce a primitive class of analytic functions, by specializing in many wellknown classes, classify Ma-Minda functions based on its conditions and their interesting geometrical aspects. Further, study a newly defined subclass of starlike functions involving a special type of Ma-Minda function introduced here for obtaining inclusion and radius results. We also establish some majorization, Bloch function norms, and other related problems for the same class. 展开更多
关键词 Ma-Minda function typically real function Hankel determinants sharp coefficient bounds radius problems logarithmic function
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Real-Valued Functions and Some Covering Properties 被引量:2
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作者 Erguang YANG Li WANG 《Journal of Mathematical Research with Applications》 CSCD 2016年第5期561-567,共7页
In the paper [properties defined with semi-continuous functions and some related spaces', Houston J. Math., 2015, 41(3): 1097-1106] properties (UL)m^wl, (UL)mK and (UL)m were defined and it was shown that sp... In the paper [properties defined with semi-continuous functions and some related spaces', Houston J. Math., 2015, 41(3): 1097-1106] properties (UL)m^wl, (UL)mK and (UL)m were defined and it was shown that spaces having these properties coincide with countably paracompact spaces, countably mesocompact spaces and countably metacompact spaces, respectively. In this paper, we continue with the study on the relationship between properties defined with real-valued functions and some covering properties. Some characterizations of countably compact spaces and pseudo-compact spaces in terms of real-valued functions are obtained. 展开更多
关键词 real-valued functions countably compact spaces pseudo-compact spaces inser-tion theorems
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A Certain Subclass of Analytic Functions with Bounded Positive Real Part 被引量:2
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作者 Young Jae Sim Oh Sang Kwon 《Advances in Pure Mathematics》 2013年第4期409-414,共6页
For real numbers α and β such that 0≤α<1<β, we denote by T(α,β) the class of normalized analytic functions which satisfy , where U denotes the open unit disk. We find some relationships involving function... For real numbers α and β such that 0≤α<1<β, we denote by T(α,β) the class of normalized analytic functions which satisfy , where U denotes the open unit disk. We find some relationships involving functions in the class T(α,β). And we estimate the bounds of coefficients and solve Fekete-Szego problem for functions in this class. Furthermore, we investigate the bounds of initial coefficients of inverse functions or bi-univalent functions. 展开更多
关键词 functions of Bounded Positive real Part Fekete-Szego Problem Inverse functions Bi-Univalent functions
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Multistability of delayed complex-valued recurrent neural networks with discontinuous real-imaginarytype activation functions
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作者 黄玉娇 胡海根 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期271-279,共9页
In this paper, the multistability issue is discussed for delayed complex-valued recurrent neural networks with discontinuous real-imaginary-type activation functions. Based on a fixed theorem and stability definition,... In this paper, the multistability issue is discussed for delayed complex-valued recurrent neural networks with discontinuous real-imaginary-type activation functions. Based on a fixed theorem and stability definition, sufficient criteria are established for the existence and stability of multiple equilibria of complex-valued recurrent neural networks. The number of stable equilibria is larger than that of real-valued recurrent neural networks, which can be used to achieve high-capacity associative memories. One numerical example is provided to show the effectiveness and superiority of the presented results. 展开更多
关键词 complex-valued recurrent neural network discontinuous real-imaginary-type activation function MULTISTABILITY delay
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Finite Type Transcendental Entire Functions Whose Buried Points Set Contains Unbounded Positive Real Interval
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作者 Feng Guo 《Advances in Pure Mathematics》 2014年第5期209-212,共4页
Let fμ(z)=z·ep(z)+μ with p(z) being real coefficient polynomial and it's leading coefficient be positive, μ∈R+, when p(z) and μ satisfy two certain conditions, buried point set of fμ(z) contains unbound... Let fμ(z)=z·ep(z)+μ with p(z) being real coefficient polynomial and it's leading coefficient be positive, μ∈R+, when p(z) and μ satisfy two certain conditions, buried point set of fμ(z) contains unbounded positive real interval. 展开更多
关键词 TRANSCENDENTAL Entire functions Julia SET BURIED POINTS SET real INTERVAL
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改进YOLOv8的矿井人员防护装备实时监测方法研究 被引量:3
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作者 张磊 孙志鹏 +3 位作者 陶虹京 郝尚凯 燕倩如 李熙尉 《煤炭科学技术》 北大核心 2025年第S1期354-365,共12页
穿戴个人防护装备是保障矿井人员作业安全的重要手段,开展矿井人员防护装备监测是煤矿安全管理的重要工作内容。煤矿井下环境较为复杂,视频监控易受到噪声、光照以及粉尘等因素干扰,导致现有的目标检测方法对矿井人员防护装备存在检测... 穿戴个人防护装备是保障矿井人员作业安全的重要手段,开展矿井人员防护装备监测是煤矿安全管理的重要工作内容。煤矿井下环境较为复杂,视频监控易受到噪声、光照以及粉尘等因素干扰,导致现有的目标检测方法对矿井人员防护装备存在检测精度低、实时性差、模型复杂度高等问题。为此,提出一种改进YOLOv8的矿井人员防护装备实时监测方法,称为DBE-YOLO。DBEYOLO模型首先在基准模型主干网络的CBS模块中结合可变形卷积(DCNv2)组成DBS模块,使卷积具有可变形能力,在采样时可以更贴近检测物体的真实形状和尺寸,更具有鲁棒性,有效提升了其对不同尺度目标的特征获取能力,有利于模型提取更多人员防护装备的特征信息,提高模型检测精度。其次在特征增强网络融合了加权双向特征金字塔机制(BiFPN),在多尺度特征融合过程中删除效率较低的特征传输节点,实现更高层次的融合,提高了对不同尺度特征的融合效率,同时BiFPN引入了一个可以学习的权值,有助于让网络学习不同输入特征的重要性。最后使用WIoUv3作为模型的损失函数,其通过动态分配梯度增益,重点关注普通锚框质量,在模型训练过程中减少了低质量锚框产生的有害梯度,进一步提升了模型性能。实验结果表明,DBE-YOLO模型在矿井人员防护装备监测中有着良好的效果,查准率、查全率、平均精度分别为93.1%、93.0%、95.8%,相较于基准模型分别提高0.8%,2.9%,2.9%,检测实时性提升到65 f·s^(-1),提高了8.3%,此外,参数量、浮点计算量、模型体积分别为2 M、6.6 G、4.4 MB,相较于原模型分别降低33.3%、18.5%、30.2%。使用煤矿现场作业视频监控对改进模型进行验证,其有效改善了漏检和误检问题,为提高矿井人员的作业安全提供了技术手段。 展开更多
关键词 可变形卷积 目标检测 损失函数 深度学习 实时监测
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计及用户偏好的电动汽车集群参与调频市场优化控制
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作者 茆美琴 葛星 +3 位作者 杨铖 王媛玥 杜燕 施永 《电力系统自动化》 北大核心 2025年第14期130-140,共11页
大规模电动汽车(EV)可以聚合为高效、灵活的调频资源。然而,电动汽车聚合商(EVA)的调节潜力易受EV用户行为与调频市场价格随机性的影响,增加了电网频率控制的复杂度和风险。为此,提出一种考虑EV用户偏好和电价随机性的EVA参与调频市场... 大规模电动汽车(EV)可以聚合为高效、灵活的调频资源。然而,电动汽车聚合商(EVA)的调节潜力易受EV用户行为与调频市场价格随机性的影响,增加了电网频率控制的复杂度和风险。为此,提出一种考虑EV用户偏好和电价随机性的EVA参与调频市场的分层随机优化控制。其中,上层以调频成本为优化目标,频率偏差为概率约束,构建机会约束规划模型得到EVA和火电机组等不同调频主体的调度功率;下层采用多元高斯Copula函数构建考虑EV用户偏好和电价随机性的EVA调度指令优化分解控制模型。以15 000辆EV参与区域电网调频为例,采用实时数字仿真系统(RTDS)搭建IEEE 39节点模型,对比了3种类型EV用户偏好、荷电状态和里程价格对EVA系统调节功率、调频经济和技术性能的影响,同时所获得的结果可为含EV的电力系统调频风险决策提供技术支撑。 展开更多
关键词 电动汽车 聚合商 调频 机会约束规划 COPULA函数 实时数字仿真
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Preliminary Clinical Study of Real-time Three-dimensional Echo-cardiographic Volume-time Curve in Evaluating Left Ventricular Diastolic Function
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作者 费洪文 何亚乐 +3 位作者 侯跃双 许燕 黄新胜 冯碧霞 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期475-478,共4页
The volume-time curve change in patients with normal left ventricular (LV) diastolic function and diastolic dysfunction was evaluated by real-time three-dimensional echocardiography (RT3DE). LV diastolic dysfuncti... The volume-time curve change in patients with normal left ventricular (LV) diastolic function and diastolic dysfunction was evaluated by real-time three-dimensional echocardiography (RT3DE). LV diastolic dysfunction was defined by E'〈A' in pulse-wave tissue Doppler for inter-ventricular septal (IVS) of mitral annulus. In 24 patients with LV diastolic dysfunction, including 12 patients with delayed relaxation (delayed relaxation group) and 12 patients with pseudo-normal function (pseudo-normal group) and 24 normal volunteers (control group), data of full-volume image were acquired by real-time three-dimensional echocardiography and subjected to volume-time curve analysis. EDV (end-diastolic volume), ESV (end-systolic volume), LVEF (left ventricular ejection fraction), PER (peak ejection rate), PFR (peak filling rate) from RT3DE were examined in the three groups. Compared to the control group, PFR (diastolic filling index of RT3DE) was significantly reduced in the delayed relaxation group and pseudo-normal group (P〈0.05). There were no significant differences in EDV, ESV, LVEE PER (P〉0.05). It is concluded that PFR, as a diastolic filling index of RT3DE, can reflect the early diastolic function and serve as a new non-invasive, quick and accurate tool for clinical assessment of LV diastolic function. 展开更多
关键词 real-time three-dimensional echocardiography left ventricular diastolic function volume-time curve
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Sub-Differential Characterizations of Non-Smooth Lower Semi-Continuous Pseudo-Convex Functions on Real Banach Spaces
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作者 Akachukwu Offia Ugochukwu Osisiogu +4 位作者 Theresa Efor Friday Oyakhire Monday Ekhator Friday Nkume Sunday Aloke 《Open Journal of Optimization》 2023年第3期99-108,共10页
In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Su... In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Sub-differential. We extend the results on the characterizations of non-smooth convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the monotonicity of its sub-differentials to the lower semi-continuous pseudo-convex functions on real Banach spaces. 展开更多
关键词 real Banach Spaces Pseudo-Convex functions Pseudo-Monotone Maps Sub-Differentials Lower Semi-Continuous functions and Approximate Mean Value Inequality
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Predictors of functional benefit of hepatitis C therapy in a‘real-life’cohort
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作者 Niels Steinebrunner Kerstin Stein +3 位作者 Catharina Sandig Thomas Bruckner Wolfgang Stremmel Anita Pathil 《World Journal of Gastroenterology》 SCIE CAS 2018年第7期852-861,共10页
AIM To define predictors of functional benefit of direct-acting antivirals(DAAs) in patients with chronic hepatitis C virus(HCV) infection and liver cirrhosis.METHODS We analysed a cohort of 199 patients with chronic ... AIM To define predictors of functional benefit of direct-acting antivirals(DAAs) in patients with chronic hepatitis C virus(HCV) infection and liver cirrhosis.METHODS We analysed a cohort of 199 patients with chronic HCV genotype 1, 2, 3 and 4 infection involving previously treated and untreated patients with compensated(76%) and decompensated(24%) liver cirrhosis at two tertiary centres in Germany. Patients were included withtreatment initiation between February 2014 and August 2016. All patients received a combination regimen of one or more DAAs for either 12 or 24 wk. Predictors of functional benefit were assessed in a univariable as well as multivariable model by binary logistic regression analysis.RESULTS Viral clearance was achieved in 88%(175/199) of patients. Sustained virological response(SVR) 12 rates were as follows: among 156 patients with genotype 1 infection the SVR 12 rate was 90%(n = 141); among 7 patients with genotype 2 infection the SVR 12 rate was 57%(n = 4); among 30 patients with genotype 3 infection the SVR 12 rate was 87%(n = 26); and among 6 patients with genotype 4 infection the SVR 12 rate was 67%(n = 4). Follow-up MELD scores were available for 179 patients. A MELD score improvement was observed in 37%(65/179) of patients, no change of MELD score in 41%(74/179) of patients, and an aggravation was observed in 22%(40/179) of patients. We analysed predictors of functional benefit from antiviral therapy in our patients beyond viral eradication. We identified the Child-Pugh score, the MELD score, the number of platelets and the levels of albumin and bilirubin as significant factors for functional benefit.CONCLUSION Our data may contribute to the discussion of potential risks and benefits of antiviral therapy with individual patients infected with HCV and with advanced liver disease. 展开更多
关键词 functionAL BENEFIT direct ACTING ANTIVIRAL hepatitis C cirrhosis real-life data
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A Real-Time Transient Analysis of a Functionally Graded Material Plate Using Reduced-Basis Methods
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作者 Yonghui Huang Yi Huang 《Advances in Linear Algebra & Matrix Theory》 2015年第3期98-108,共11页
Based on the hybrid numerical method (HNM) combining with a reduced-basis method (RBM), the real-time transient response of a functionally graded material (FGM) plates is obtained. The large eigenvalue problem in wave... Based on the hybrid numerical method (HNM) combining with a reduced-basis method (RBM), the real-time transient response of a functionally graded material (FGM) plates is obtained. The large eigenvalue problem in wavenumber domain has been solved through real-time off-line/on-line calculation. At off-line stage, a reduced-basis space is constructed in sample wavenumbers according to the solved eigenvalue problems. The matrices independent of parameters are projected onto the reduced-basis spaces. At on-line stage, the reduced eigenvalue problems of the arbitrary wavenumbers are built. Subsequently, the responses in wavenumber domain are obtained by the approximated eigen-pairs. Because of the application of RBM, the computational cost of transient displacement analysis of FGM plate is decreased significantly, while the accuracy of the solution and the physics of the structure are still retained. The efficiency and validity of the proposed method are demonstrated through a numerical example. 展开更多
关键词 Reduced-Basis METHOD TRANSIENT Response functionally GRADED Material Hybrid Numerical METHOD real-TIME
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Asymptotic Behaviors of Hankelians, Whose Entries Involve Regularly- or Rapidly-Varying Functions, as the Variable Tends to +∞. Part I
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作者 Antonio Granata 《Advances in Pure Mathematics》 2024年第11期817-858,共42页
The rich literature concerning “asymptotic behavior of Hankel determinants” concerns the behavior, as the order n tends to ∞, of Hankel determinants whose entries are numbers, e.g., with a combinatorial interest or... The rich literature concerning “asymptotic behavior of Hankel determinants” concerns the behavior, as the order n tends to ∞, of Hankel determinants whose entries are numbers, e.g., with a combinatorial interest or arising as values of special classes of functions. Such determinants are numbers depending on n, playing roles in number theory, combinatorics, random matrices and the like;and mathematicians in the involved fields have been interested in their asymptotic behaviors as n goes to ∞, as previously mentioned, with no single exception to the author’s knowledge. The study carried on in the present paper treats an altogether different situation as suggested by the specification in the title “as the variable tends to +∞”. We deal with those types of Hankel determinants (purposely called Hankelians) which are special cases of Wronskians and, continuing our work on the asymptotics of Wronskians, we study the asymptotic behaviors of n-order Hankelians, whose entries involve either regularly- or rapidly-varying functions, when the variable tends to +∞. As in the study of Wronskians, the treatment of this case also needs the whole apparatus of the theory of higher-order types of asymptotic variation, but the most demanding results are not automatic corollaries of the general theory. In fact, in the study of generic Wronskians (study motivated by applications to asymptotic expansions), the entries were required to belong to one of the classes of “higher-order regular or rapid variation”;on the contrary, in the case of Hankelians, we are confronted with functions whose logarithms are either “regularly- or rapidly-varying functions”, roughly classifiable as “ultrarapidly-varying functions”, and the study requires both special devices and a number of preliminary lemmas about products and linear combinations of functions in the mentioned classes. 展开更多
关键词 Asymptotic Behaviors of Hankelians Asymptotic Expansions in the real Domain Regularly- Rapidly- and Exponentially-Varying functions of Higher Order
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真实世界G-CDOP方案治疗滤泡性淋巴瘤对肝功能的影响
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作者 张晓 夏凡 +2 位作者 谢诚 曲昌菊 丁一多 《医药导报》 北大核心 2025年第11期1830-1834,共5页
目的探讨真实世界滤泡性淋巴瘤(FL)患者采用奥妥珠单抗/环磷酰胺/多柔比星脂质体/长春地辛/地塞米松(G-CDOP)方案后肝功能异常发生情况。方法通过医院信息系统,回顾性收集苏州大学附属第一医院血液内科2021年9月—2023年8月诊断为FL且... 目的探讨真实世界滤泡性淋巴瘤(FL)患者采用奥妥珠单抗/环磷酰胺/多柔比星脂质体/长春地辛/地塞米松(G-CDOP)方案后肝功能异常发生情况。方法通过医院信息系统,回顾性收集苏州大学附属第一医院血液内科2021年9月—2023年8月诊断为FL且经过至少4个疗程G-CDOP方案治疗住院患者的临床资料,分析用药后肝功能异常发生率、严重程度、损伤类型及发生时间等临床特点。结果共55例FL患者纳入研究,其中30例在G-CDOP方案治疗期间出现肝功能异常,发生率54.5%;发生1级、2级和3级肝功能异常分别为23例(41.8%)、3例(5.5%)及4例(7.3%);肝细胞损伤型、胆汁淤积型和混合型分别为12例(21.8%)、4例(7.3%)和14例(25.5%);21例(38.2%)患者肝功能异常出现在G-CDOP方案治疗第1周期,5例(9.1%)在第2周期,发生在第3、4、5周期的分别为1例(1.8%)、2例(3.6%)和1例(1.8%)。结论G-CDOP方案可对FL患者肝功能指标产生影响,但大部分为轻度且可逆,亦有严重肝损伤发生,需要引起临床重视。 展开更多
关键词 滤泡性淋巴瘤 奥妥珠单抗/环磷酰胺/多柔比星脂质体/长春地辛/地塞米松方案 奥妥珠单抗 肝功能异常 真实世界
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基于真实世界的针刺治疗缺血性脑卒中的临床疗效评价 被引量:2
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作者 邓小嫚 冯瑶婷 +3 位作者 吕鹤群 康琳玲 田烨楠 彭拥军 《中华中医药杂志》 北大核心 2025年第2期962-968,共7页
目的:采用真实世界研究探讨针刺治疗缺血性脑卒中的临床疗效及安全性。方法:156例缺血性脑卒中患者根据是否进行针刺,分为非针刺组(52例)和针刺组(104例)。以倾向评分匹配法均衡混杂因素,运用统计软件SPSS 26.0对数据进行处理,纳入32对... 目的:采用真实世界研究探讨针刺治疗缺血性脑卒中的临床疗效及安全性。方法:156例缺血性脑卒中患者根据是否进行针刺,分为非针刺组(52例)和针刺组(104例)。以倾向评分匹配法均衡混杂因素,运用统计软件SPSS 26.0对数据进行处理,纳入32对匹配成功的患者。所有患者均予规范的西医基础治疗,针刺组在此基础上加予针刺治疗。对治疗前后的美国国立院神经功能缺损评分(NIHSS)进行比较,观察针刺治疗缺血性脑卒中的临床疗效及神经功能改善情况;对治疗前后的改良Rankin量表(mRS)评分进行比较,观察患者肢体功能改善情况;对治疗前后的欧洲五维健康量表(EQ-5D)进行比较,观察患者健康相关生活质量改善情况;记录不良反应事件的发生情况,并随访发病1年时患者中风再复发与死亡事件的发生情况。结果:本研究共纳入19个协变量,匹配成功32对,匹配后两组患者协变量基线均衡可比。匹配后针刺组总有效率93.75%(30/32)显著高于非针刺组的75.00%(24/32)(P<0.05)。两组患者治疗后,针刺组的NIHSS评分、mRS评分均显著低于非针刺组(P<0.01),针刺组的EQ-5D-5L健康效用值、VAS评分均显著高于非针刺组(P<0.01)。随访1年时,针刺组患者复发率[4.81%(5/104)]、死亡率[0.96%(1/104)]低于非针刺组[复发率11.54%(6/52),死亡率1.92%(1/52)],但差异无统计学意义。结论:针刺治疗可明显改善缺血性脑卒中患者的神经功能及肢体功能,提高患者健康相关生活质量。 展开更多
关键词 针刺 缺血性脑卒中 神经功能 肢体功能 生活质量 真实世界研究
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智能汽车稳定性MPC实时性改进的显式解方法
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作者 焦恒超 舒然 +2 位作者 曾兆枫 唐小林 舒红宇 《机械工程学报》 北大核心 2025年第10期263-275,共13页
模型预测控制(Model predictive control,MPC)具有很多优点,但用于智能汽车横摆稳定性控制时,由于其动力学模型的多约束和非线性问题,致使MPC优化算法复杂,难以实现足够短的控制周期和步长。为此,提出一种智能汽车横摆稳定性MPC的在线... 模型预测控制(Model predictive control,MPC)具有很多优点,但用于智能汽车横摆稳定性控制时,由于其动力学模型的多约束和非线性问题,致使MPC优化算法复杂,难以实现足够短的控制周期和步长。为此,提出一种智能汽车横摆稳定性MPC的在线显式求解方法,使用泰勒展开将非线性模型预测控制(Nonlinear model predictive control,NMPC)转换为线性时变模型预测控制(Linear time-varying model predictive control,LTV-MPC)。再使用滚动调整的权重系数,将不等式约束优化转换为能直接显式求解的无约束优化,以避免多步迭代寻优、加快MPC求解速度。仿真试验结果表明,在保证相同控制效果前提下,所提出的显式解方法能使MPC的求解速度提高3~4倍,可显著提高智能汽车横摆稳定性MPC的实时性。 展开更多
关键词 车辆横摆稳定性 模型预测控制 实时性 惩罚函数 显式求解
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轻量化的驾驶员吸烟检测模型
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作者 陈新一 王晓强 +3 位作者 李少波 夏旭 陶乙豪 庄旭菲 《计算机工程与设计》 北大核心 2025年第2期626-632,共7页
为进一步实现在移动设备上对驾驶员吸烟的违法行为实时检测,提出一种改进的SlimYOLOv7-tiny模型。使用DSConv替换YOLOv7-tiny特征融合网络中标准3×3卷积,增加P6检测层,采用Mish激活函数,引入边框回归损失函数EIoU loss,利用Slim剪... 为进一步实现在移动设备上对驾驶员吸烟的违法行为实时检测,提出一种改进的SlimYOLOv7-tiny模型。使用DSConv替换YOLOv7-tiny特征融合网络中标准3×3卷积,增加P6检测层,采用Mish激活函数,引入边框回归损失函数EIoU loss,利用Slim剪枝算法进一步提高模型的轻量化,使用PyQt5开发图形界面程序。实验结果表明,模型在自建驾驶员吸烟数据集上与原模型相比参数量减少60.0%,计算量减小64.39%,有利于模型进一步在移动设备及嵌入式设备上的实时性检测。 展开更多
关键词 驾驶员吸烟行为 目标检测 实时 激活函数 轻量化 图形界面 剪枝算法
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逼近思想是学习“实变函数”课程的钥匙
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作者 郑智源 王福成 《科技风》 2025年第18期51-53,57,共4页
“实变函数”是数学专业最重要的专业课之一,也是大多数师生公认的最难课程。本文分析了学生在理解课程理论时的一些困难点,并针对性地指出可将逼近思想作为学生学习该课程的思想“钥匙”,探讨了逼近思想在该课程中的核心地位与其重要... “实变函数”是数学专业最重要的专业课之一,也是大多数师生公认的最难课程。本文分析了学生在理解课程理论时的一些困难点,并针对性地指出可将逼近思想作为学生学习该课程的思想“钥匙”,探讨了逼近思想在该课程中的核心地位与其重要的教学意义,并整理了多个案例来展示逼近思想在教学内容中的具体运用。在教学中引导学生掌握逼近思想,有利于帮助学生更好地理解课程理论,提高数学素养,有利于培养学生的科学精神与创新能力,并对实现立德树人,推动学生全面发展有着积极意义。 展开更多
关键词 逼近思想 实变函数 LEBESGUE积分
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基于径向基Koopman-Kalman的光学电流传感器误差预测 被引量:1
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作者 曹睿康 李岩松 +2 位作者 耿聪 刘逸伦 刘君 《电子测量与仪器学报》 北大核心 2025年第5期84-94,共11页
光学电流传感器(OCS)对温度的变化非常敏感,温度的变化导致其测量产生误差,难以达到电力系统计量的要求,因此准确预测由温度变化引起的OCS测量误差对监测其运行稳定性和保证电力系统的安全运行具有重要意义。由于OCS输出电流受温度的影... 光学电流传感器(OCS)对温度的变化非常敏感,温度的变化导致其测量产生误差,难以达到电力系统计量的要求,因此准确预测由温度变化引起的OCS测量误差对监测其运行稳定性和保证电力系统的安全运行具有重要意义。由于OCS输出电流受温度的影响具有强非线性,提出了一种适用于非线性动力系统的径向基Koopman-Kalman预测算法,解决了温度影响下OCS输出电流因强非线性而难以预测的问题。首先通过径向基函数将非线性的OCS输出电流状态量映射至高维空间形成扩展状态,采用扩展动态模态分解算法分解扩展状态计算高维空间中Koopman算子的近似矩阵。其次,采用近似的Koopman算子在高维线性空间中进行批量预测。最后,采用Kalman滤波对批量预测的最后一个预测值更新校正,以跟随系统的状态变化。以实验测量得到的OCS温度-电流数据进行实验,结果表明在不同温度变化情况下,相较于标准Koopman预测和长短期记忆(LSTM)预测,所提出预测算法的均方误差(MSE)均减小90%以上,证明了所提算法的有效性。 展开更多
关键词 光学电流传感器 径向基函数 Koopman算子 卡尔曼滤波 实时预测
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基于实时应用的头部姿态估计算法 被引量:2
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作者 高强 丁兵如 +2 位作者 董昌林 谢英红 韩晓微 《沈阳大学学报(自然科学版)》 2025年第1期25-33,F0002,F0003,共11页
针对实时视频中头部姿势准确估计的问题,提出了一种创新的6DRepNet-MobileViT模型。该模型采用改进的MobileNetV2作为骨干网络,通过降低训练复杂性,实现了训练速度与精度的平衡,使用Hard-Swish函数,解决了较大的数值范围导致的精度下降... 针对实时视频中头部姿势准确估计的问题,提出了一种创新的6DRepNet-MobileViT模型。该模型采用改进的MobileNetV2作为骨干网络,通过降低训练复杂性,实现了训练速度与精度的平衡,使用Hard-Swish函数,解决了较大的数值范围导致的精度下降问题。使用混合损失函数,将地标距离损失函数与姿态欧拉角损失函数结合,更全面地提高了姿态估计的准确性。在公共数据集AFLW2000和BIWI上进行实验,结果表明:6DRepNet-MobileViT在各种复杂场景中均表现出高效的估计性能。 展开更多
关键词 头部姿态估计 实时视频 6DRepNet MobileViT 混合损失函数
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