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Interleukin 1βreceptor and synaptic dysfunction in recurrent brain infection with Herpes simplex virus type-1
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作者 Roberto Piacentini Claudio Grassi 《Neural Regeneration Research》 SCIE CAS 2025年第2期416-423,共8页
Several experimental evidence suggests a link between brain Herpes simplex virus type-1 infection and the occurrence of Alzheimer’s disease.However,the molecular mechanisms underlying this association are not complet... Several experimental evidence suggests a link between brain Herpes simplex virus type-1 infection and the occurrence of Alzheimer’s disease.However,the molecular mechanisms underlying this association are not completely understood.Among the molecular mediators of synaptic and cognitive dysfunction occurring after Herpes simplex virus type-1 infection and reactivation in the brain neuroinflammatory cytokines seem to occupy a central role.Here,we specifically reviewed literature reports dealing with the impact of neuroinflammation on synaptic dysfunction observed after recurrent Herpes simplex virus type-1 reactivation in the brain,highlighting the role of interleukins and,in particular,interleukin 1βas a possible target against Herpes simplex virus type-1-induced neuronal dysfunctions. 展开更多
关键词 herpes simplex virus type 1 interleukin MICROGLIA NEUROINFLAMMATION synaptic dysfunction
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Herpes simplex virus 2-induced aseptic meningitis presenting with sudden deafness:A case report
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作者 Yuan-Cheng Liu Shih-Hsuan Hsiao Peir-Rong Chen 《World Journal of Clinical Cases》 SCIE 2025年第8期22-25,共4页
BACKGROUND Aseptic meningitis is defined as meningeal inflammation caused by various etio-logies with negative cerebrospinal fluid(CSF)bacterial culture.The most common etiologies are viruses[enteroviruses,arboviruses... BACKGROUND Aseptic meningitis is defined as meningeal inflammation caused by various etio-logies with negative cerebrospinal fluid(CSF)bacterial culture.The most common etiologies are viruses[enteroviruses,arboviruses,and herpes simplex virus type 2(HSV-2)].Aseptic meningitis can have various presentations,including sensori-neural deafness.While sensorineural deafness from mumps meningoencephalitis has been reported,cases of HSV-2-induced hearing loss are rare.Herein,we re-port a case of HSV-2-induced meningitis that presented with sudden deafness.CASE SUMMARY A 68-year-old man experienced a profound sudden onset of left-sided hearing loss for one day.Pure-tone audiograms demonstrated sudden left-sided sensorineural hearing loss(thresholds 80-90 dB).After treatment with high-dose steroids for 1 week,he experienced an acute consciousness change with left hemiparesis.The laboratory data showed no significant abnormalities.Brain computed tomography without contrast and magnetic resonance imaging revealed no intracranial hemo-rrhage or obvious brain lesion.The CSF analysis and the Multiplex PCR panels showed HSV-2 positivity.Hence,under the diagnosis of herpes meningoenceph-alitis,acyclovir was prescribed and his symptoms gradually resolved.CONCLUSION This case report further demonstrates that a viral infection could be a cause of sudden sensorineural hearing loss. 展开更多
关键词 Aseptic meningitis Type 2 herpes simplex Sudden sensorineural hearing loss IMMUNOCOMPROMISED Cerebrospinal fluid Case report
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利用B-splines特性计算PbS量子点中的激子基态能量的量子尺寸效应 被引量:3
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作者 惠萍 《计算物理》 CSCD 北大核心 2007年第6期753-756,共4页
利用B-splines特性构建量子点中激子的波函数,计算PbS量子点中激子的基态能量Eg的量子尺寸效应,并将计算结果与实验结果及其他理论计算结果进行比较;利用B-splines技术计算的激子的基态能量在整个区域与实验完全符合,同时计算了有效质... 利用B-splines特性构建量子点中激子的波函数,计算PbS量子点中激子的基态能量Eg的量子尺寸效应,并将计算结果与实验结果及其他理论计算结果进行比较;利用B-splines技术计算的激子的基态能量在整个区域与实验完全符合,同时计算了有效质量和势垒高度对基态能量Eg的量子尺寸效应的影响. 展开更多
关键词 b-splines 量子点 基态能量 量子尺寸效应 有效质量
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用B-splines技术计算超强平行外磁场中氢分子离子的能级 被引量:3
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作者 惠萍 《计算物理》 EI CSCD 北大核心 2010年第3期451-456,共6页
考虑两核之间的相互作用,采用单中心展开方法和B-splines技术构建氢分子离子的径向和角向波函数,计算超强平行外磁场中氢分子离子的能级Eb(m=0,-1,-2,-3,-4,-5)和两核间的平衡距离2R.计算中,磁场强度从2.35×106T变到2.35×108T... 考虑两核之间的相互作用,采用单中心展开方法和B-splines技术构建氢分子离子的径向和角向波函数,计算超强平行外磁场中氢分子离子的能级Eb(m=0,-1,-2,-3,-4,-5)和两核间的平衡距离2R.计算中,磁场强度从2.35×106T变到2.35×108T.对比绝热变分近似计算结果,计算精度提高的范围在0.00015Ry~0.0488Ry之间;对比变分近似计算结果,计算精度提高的范围在0.0029Ry~0.0257Ry之间.这些计算结果表明,用二重B-splines基函数展开方法使氢分子离子的波函数的完备性更好,并能得到比绝热变分近似和绝热近似方法更高的计算精度. 展开更多
关键词 氢分子离子 b-spline技术 超强平行外磁场 绝热变分近似
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基于B-Splines网络的飞行姿态控制器设计
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作者 秦硕 孙秀霞 +2 位作者 薛建平 张渤雨 成万舟 《飞行力学》 CSCD 北大核心 2008年第1期40-43,共4页
设计了一种自适应飞行姿态控制器,在某一飞行条件下,建立了某型飞机的滚转通道动态逆模型,针对动态逆控制需要获得飞机精确数学模型的难点,基于B-Splines函数,构建了B-Splines网络,在线逼近模型逆误差,并根据李亚普诺夫能量函数推导了B-... 设计了一种自适应飞行姿态控制器,在某一飞行条件下,建立了某型飞机的滚转通道动态逆模型,针对动态逆控制需要获得飞机精确数学模型的难点,基于B-Splines函数,构建了B-Splines网络,在线逼近模型逆误差,并根据李亚普诺夫能量函数推导了B-Splines网络权值的更新算法,确保模型跟踪误差和网络权值的有界性。仿真结果表明,该控制器能够对模型逆误差快速自适应,系统对输入命令有较好的响应特性。 展开更多
关键词 动态逆 b-splines网络 姿态控制系统
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B-Spline曲线聚风装置直线翼垂直轴风力机启动性能数值模拟 被引量:1
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作者 李岩 马云飞 +2 位作者 佟国强 杨胜兵 肖振军 《排灌机械工程学报》 CSCD 北大核心 2024年第3期265-272,共8页
为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进... 为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进行设计:聚风装置与风轮间隙距离ΔL、底圆半径R_(1)、顶圆半径R_(2)、入口角度α_(1)和出口角度α_(2).设计方法采用二次旋转正交组合筛选最优模型,通过三维数值模拟研究聚风装置参数对直线翼垂直轴风力机启动性能的影响,获得了最佳外形参数组合.此外,对有无加装聚风装置的直线翼垂直轴风力机进行了静态三维数值模拟.结果表明,通过添加具有外凸流线型轮廓的聚风装置,直线翼垂直轴风力机的启动性能有显著提升.在风速较低的情况下,性能改善更加明显.聚风装置可使直线翼垂直轴风力机的平均启动力矩系数最大增加38.8%,峰值平均启动力矩系数最大可增加31.2%. 展开更多
关键词 垂直轴风力机 聚风装置 b-spline曲线 启动性能 数值模拟
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基于二维B-splines方法研究强磁场中类氢离子He+的低能能级
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作者 刘凤丽 《黑龙江大学自然科学学报》 2023年第5期596-604,共9页
采用改进的二维B-spline方法在柱坐标系下研究了强磁场下类氢离子He^(+)的结构和电子空间几率密度,计算包含三种对称性0^(+)、0^(-)和(^(-)1)^(+)共10个本征态1 0^(+)、2 0^(+)、ν 0^(-)(ν=1~4)和ν(-1)^(+)(ν=1~4)的能级,选定磁感... 采用改进的二维B-spline方法在柱坐标系下研究了强磁场下类氢离子He^(+)的结构和电子空间几率密度,计算包含三种对称性0^(+)、0^(-)和(^(-)1)^(+)共10个本征态1 0^(+)、2 0^(+)、ν 0^(-)(ν=1~4)和ν(-1)^(+)(ν=1~4)的能级,选定磁感应强度分别为0、0.001、0.003、0.005、0.007、0.010、0.030、0.050、0.070、0.100、0.200、0.300、0.500、0.700和1.000 a.u.。计算结果表明,类氢离子He^(+)的能级在强磁场中发生劈裂,简并度消除,得到了各个能级随磁感应强度变化规律,并且发现随着磁感应强度的增加能级高低会改变,甚至会发生能级翻转现象;定量地研究了类氢离子He^(+)的基态1 0^(+)和激发态3 0^(-)几率密度分布随磁感应强度的变化规律,并与氢原子进行比较。本研究部分计算结果与他人研究结果十分吻合,有助于进一步理解其他复杂原子的电子运动行为。 展开更多
关键词 b-spline方法 类氢离子He+ 强磁场 能级
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Multi-modality liver image registration based on multilevel B-splines free-form deformation and L-BFGS optimal algorithm 被引量:1
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作者 宋红 李佳佳 +1 位作者 王树良 马婧婷 《Journal of Central South University》 SCIE EI CAS 2014年第1期287-292,共6页
A new coarse-to-fine strategy was proposed for nonrigid registration of computed tomography(CT) and magnetic resonance(MR) images of a liver.This hierarchical framework consisted of an affine transformation and a B-sp... A new coarse-to-fine strategy was proposed for nonrigid registration of computed tomography(CT) and magnetic resonance(MR) images of a liver.This hierarchical framework consisted of an affine transformation and a B-splines free-form deformation(FFD).The affine transformation performed a rough registration targeting the mismatch between the CT and MR images.The B-splines FFD transformation performed a finer registration by correcting local motion deformation.In the registration algorithm,the normalized mutual information(NMI) was used as similarity measure,and the limited memory Broyden-Fletcher- Goldfarb-Shannon(L-BFGS) optimization method was applied for optimization process.The algorithm was applied to the fully automated registration of liver CT and MR images in three subjects.The results demonstrate that the proposed method not only significantly improves the registration accuracy but also reduces the running time,which is effective and efficient for nonrigid registration. 展开更多
关键词 multi-modal image registration affine transformation b-splines free-form deformation (FFD) L-BFGS
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Herpes simplex keratitis:A brief clinical overview 被引量:3
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作者 Mutali Musa Ehimare Enaholo +4 位作者 Gladness Aluyi-Osa George Nnamdi Atuanya Leopoldo Spadea Carlo Salati Marco Zeppieri 《World Journal of Virology》 2024年第1期5-32,共28页
The aim of our minireview is to provide a brief overview of the diagnosis,clinical aspects,treatment options,management,and current literature available regarding herpes simplex keratitis(HSK).This type of corneal vir... The aim of our minireview is to provide a brief overview of the diagnosis,clinical aspects,treatment options,management,and current literature available regarding herpes simplex keratitis(HSK).This type of corneal viral infection is caused by the herpes simplex virus(HSV),which can affect several tissues,including the cornea.One significant aspect of HSK is its potential to cause recurrent episodes of inflammation and damage to the cornea.After the initial infection,the HSV can establish a latent infection in the trigeminal ganglion,a nerve cluster near the eye.The virus may remain dormant for extended periods.Periodic reactivation of the virus can occur,leading to recurrent episodes of HSK.Factors triggering reactivation include stress,illness,immunosuppression,or trauma.Recurrent episodes can manifest in different clinical patterns,ranging from mild epithelial involvement to more severe stromal or endothelial disease.The severity and frequency of recurrences vary among individuals.Severe cases of HSK,especially those involving the stroma and leading to scarring,can result in vision impairment or even blindness in extreme cases.The cornea's clarity is crucial for good vision,and scarring can compromise this,potentially leading to visual impairment.The management of HSK involves not only treating acute episodes but also implementing long-term strategies to prevent recurrences and attempt repairs of corneal nerve endings via neurotization.Antiviral medications,such as oral Acyclovir or topical Ganciclovir,may be prescribed for prophylaxis.The immune response to the virus can contribute to corneal damage.Inflammation,caused by the body's attempt to control the infection,may inadvertently harm the corneal tissues.Clinicians should be informed about triggers and advised on measures to minimize the risk of reactivation.In summary,the recurrent nature of HSK underscores the importance of both acute and long-term management strategies to preserve corneal health and maintain optimal visual function. 展开更多
关键词 Herpes simplex virus Herpes simplex keratitis ACYCLOVIR NEUROTIZATION REACTIVATION
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An improved time integration scheme based on uniform cubic B-splines and its application in structural dynamics
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作者 Weibin WEN Hongshuai LEI +3 位作者 Kai WEI Baosheng XU Shengyu DUAN Daining FANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第6期889-908,共20页
A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom (S... A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom (SDOF) system, and then is generalized for a multiple-degree of freedom (MDOF) system. Stability analysis shows that, with an adjustable algorithmic parameter, the proposed method can achieve both conditional and unconditional stabilities. Validity of the method is shown with four numerical simulations. Comparison between the proposed method and other methods shows that the proposed method possesses high computation accuracy and desirable computation efficiency. 展开更多
关键词 dynamical system time integration~ stability dynamic response b-spline
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Non-Rigid Image Registration Algorithm Based on B-Splines Approximation
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作者 张红颖 张加万 +1 位作者 孙济洲 孙毅刚 《Transactions of Tianjin University》 EI CAS 2007年第6期447-451,共5页
An intensity-based non-rigid registration algorithm is discussed, which uses Gaussian smoothing to constrain the transformation to be smooth, and thus preserves the topology of images. In view of the insufficiency of ... An intensity-based non-rigid registration algorithm is discussed, which uses Gaussian smoothing to constrain the transformation to be smooth, and thus preserves the topology of images. In view of the insufficiency of the uniform Gaussian filtering of the deformation field, an automatic and accurate non-rigid image registration method based on B-splines approximation is proposed. The regularization strategy is adopted by using multi-level B-splines approximation to regularize the displacement fields in a coarse-to-fine manner. Moreover, it assigns the different weights to the estimated displacements according to their reliabilities. In this way, the level of regularity can be adapted locally. Experiments were performed on both synthetic and real medical images of brain, and the results show that the proposed method improves the registration accuracy and robustness. 展开更多
关键词 non-rigid image registration b-splines approximation REGULARIZATION
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Numerical Solution of Functional Integral and Integro-Differential Equations by Using B-Splines
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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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Extraction of Feature Points for Non-Uniform Rational B-Splines(NURBS)-Based Modeling of Human Legs
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作者 WANG Xi WU Zongqian LI Qiao 《Journal of Donghua University(English Edition)》 CAS 2022年第4期299-303,共5页
Methods of digital human modeling have been developed and utilized to reflect human shape features.However,most of published works focused on dynamic visualization or fashion design,instead of high-accuracy modeling,w... Methods of digital human modeling have been developed and utilized to reflect human shape features.However,most of published works focused on dynamic visualization or fashion design,instead of high-accuracy modeling,which was strongly demanded by medical or rehabilitation scenarios.Prior to a high-accuracy modeling of human legs based on non-uniform rational B-splines(NURBS),the method of extracting the required quasi-grid network of feature points for human legs is presented in this work.Given the 3 D scanned human body,the leg is firstly segmented and put in standardized position.Then re-sampling of the leg is conducted via a set of equidistant cross sections.Through analysis of leg circumferences and circumferential curvature,the characteristic sections of the leg as well as the characteristic points on the sections are then identified according to the human anatomy and shape features.The obtained collection can be arranged to form a grid of data points for knots calculation and high-accuracy shape reconstruction in future work. 展开更多
关键词 3D scan digital human modeling non-uniform rational b-splines(NURBS) feature extraction
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On the Implementation of Exponential B-Splines by Poisson Summation Formula
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作者 Sinuk Kang 《Journal of Applied Mathematics and Physics》 2016年第4期637-640,共4页
Polynomial splines have played an important role in image processing, medical imaging and wavelet theory. Exponential splines which are of more general concept have been recently investigated.We focus on cardinal expo... Polynomial splines have played an important role in image processing, medical imaging and wavelet theory. Exponential splines which are of more general concept have been recently investigated.We focus on cardinal exponential splines and develop a method to implement the exponential B-splines which form a Riesz basis of the space of cardinal exponential splines with finite energy. 展开更多
关键词 Exponential Splines b-splines Poisson Summation Formula
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Black Garlic as an Antiviral for Herpes Simplex Virus-2 in Lung Cells
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作者 Jenna R. Horowitz Lee H. Lee Sandra D. Adams 《Advances in Bioscience and Biotechnology》 CAS 2024年第1期70-89,共20页
Allicin, an antioxidant, is known for providing garlic with its unique fragrance and taste, as well as for its antimicrobial properties. Black garlic, a fermented form of garlic, contains higher levels of antioxidants... Allicin, an antioxidant, is known for providing garlic with its unique fragrance and taste, as well as for its antimicrobial properties. Black garlic, a fermented form of garlic, contains higher levels of antioxidants than fresh garlic. Antioxidants play a vital role in alleviating cellular stress during viral infections. Viral infections result in oxidative stress through the production of reactive oxidative species (ROS). A prolonged state of oxidative stress can result in cell death, DNA damage, and disease progression. In this study, black garlic extract (BGE) is evaluated for its ability to mitigate cytopathic effects and oxidative stress caused by herpes simplex virus-2 (HSV-2) infections in vitro. Antiviral assays were performed to determine the percent of viral inhibition resulting from treatment with the BGE. ROS-Glo<sup>TM</sup> H<sub>2</sub>O<sub>2</sub> assays were then completed to measure the post-infection ROS levels of BGE-treated virus and cells. The results thus far suggest that BGE may inhibit viral infection and decrease levels of oxidative stress. 展开更多
关键词 Black Garlic Herpes simplex Virus-2 ANTIOXIDANT ANTIVIRAL ALLICIN
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Study on Joint Method of 3D Acoustic Emission Source Localization Simplex and Grid Search Scanning
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作者 Liu Wei-jian Wang Hao-nan +4 位作者 Xiao Yang Hou Meng-jie Dong Sen-sen Zhang Zhi-zeng Lu Gao-ming 《Applied Geophysics》 SCIE CSCD 2024年第3期456-467,617,共13页
Acoustic emission(AE)source localization is a fundamental element of rock fracture damage imaging.To improve the efficiency and accuracy of AE source localization,this paper proposes a joint method comprising a three-... Acoustic emission(AE)source localization is a fundamental element of rock fracture damage imaging.To improve the efficiency and accuracy of AE source localization,this paper proposes a joint method comprising a three-dimensional(3D)AE source localization simplex method and grid search scanning.Using the concept of the geometry of simplexes,tetrahedral iterations were first conducted to narrow down the suspected source region.This is followed by a process of meshing the region and node searching to scan for optimal solutions,until the source location is determined.The resulting algorithm was tested using the artificial excitation source localization and uniaxial compression tests,after which the localization results were compared with the simplex and exhaustive methods.The results revealed that the localization obtained using the proposed method is more stable and can be effectively avoided compared with the simplex localization method.Furthermore,compared with the global scanning method,the proposed method is more efficient,with an average time of 10%–20%of the global scanning localization algorithm.Thus,the proposed algorithm is of great significance for laboratory research focused on locating rupture damages sustained by large-sized rock masses or test blocks. 展开更多
关键词 acoustic emission simplex form grid search scan locating the epicenter
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Bilateral meibomian gland morphological alterations in unilateral herpes simplex keratitis based on artificial intelligence analysis
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作者 Xin-Xin Yu Xue-Wen Chen +1 位作者 Qi Dai Shuang-Qing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2153-2157,共5页
AIM:To explore whether unilateral herpes simplex keratitis(HSK)can cause morphological changes of bilateral meibomian glands(MGs)based on artificial intelligence(AI)analytical system.METHODS:In the retrospective study... AIM:To explore whether unilateral herpes simplex keratitis(HSK)can cause morphological changes of bilateral meibomian glands(MGs)based on artificial intelligence(AI)analytical system.METHODS:In the retrospective study,29 patients with unilateral HSK and 29 participants matched in terms of age and sex were included as control group.Meibographic images of the upper eyelid using Keratograph 5M and assessed ocular surface parameters including tear meniscus height and tear break-up time.MG density and vagueness values were automatically analyzed and calculated using an AI analytical system.We compared the differences between the affected and the contralateral unaffected eyes in HSK patients,and the normal control eyes.We employed either the paired t-test or the Wilcoxon signed-rank test to compare significant difference between the affected and unaffected eyes in HSK patients or between the HSK group and control group.RESULTS:The MG density was 0.19±0.09 in the HSKaffected eye and 0.18±0.07 in contralateral unaffected eye,which had no significant difference(P=0.616).The MG density between the affected eye with HSK and the normal control group was statistically significant(P=0.028).There was a significant difference in MG density between the contralateral unaffected eye and the normal control group(P=0.012).However,no significant difference in vagueness value was observed between the eye with HSK and the control group or between HSK eye and contralateral eye.CONCLUSION:The MG density between the HSKaffected eye and the contralateral unaffected eye don’t significantly differ,whereas there is a significant decrease in the HSK group compared to that of the normal participants.Unilateral HSV keratitis may suffer from bilateral changes of MG morphology indicating bilateral dry eye.Therefore,the fellow eye of patients with unilateral HSK should be considered a potential case of MG dysfunction,necessitating early treatment for bilateral dry eye in the clinic. 展开更多
关键词 herpes simplex keratitis artificial intelligence meibomian gland morphology bilateral alterations
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A BICUBIC B-SPLINE FINITE ELEMENT METHOD FOR FOURTH-ORDER SEMILINEAR PARABOLIC OPTIMAL CONTROL PROBLEMS
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作者 Fangfang DU Tongjun SUN 《Acta Mathematica Scientia》 SCIE CSCD 2024年第6期2411-2421,共11页
A bicubic B-spline finite element method is proposed to solve optimal control problems governed by fourth-order semilinear parabolic partial differential equations.Its key feature is the selection of bicubic B-splines... A bicubic B-spline finite element method is proposed to solve optimal control problems governed by fourth-order semilinear parabolic partial differential equations.Its key feature is the selection of bicubic B-splines as trial functions to approximate the state and costate variables in two space dimensions.A Crank-Nicolson difference scheme is constructed for time discretization.The resulting numerical solutions belong to C2in space,and the order of the coefficient matrix is low.Moreover,the Bogner-Fox-Schmit element is considered for comparison.Two numerical experiments demonstrate the feasibility and effectiveness of the proposed method. 展开更多
关键词 bicubic b-spline finite element method optimal control problem Bogner-Fox-Schmit element Crank-Nicolson scheme numerical experiment
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基于B-spline的路径规划与轨迹跟踪研究
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作者 庞同嘉 王金波 田宇洋 《农业装备与车辆工程》 2024年第7期50-55,61,共7页
为满足局部路径规划换道路径下的特性和提高智能驾驶车辆在多种变曲率条件下的路径跟踪精度和稳定性,采用贝塞尔曲线、B-spline等路径规划换道条件下的方法,分别在圆形轨迹、8字形轨迹、S形轨迹、正弦曲线形轨迹路径下,基于MATLAB对4类... 为满足局部路径规划换道路径下的特性和提高智能驾驶车辆在多种变曲率条件下的路径跟踪精度和稳定性,采用贝塞尔曲线、B-spline等路径规划换道条件下的方法,分别在圆形轨迹、8字形轨迹、S形轨迹、正弦曲线形轨迹路径下,基于MATLAB对4类路径跟踪算法进行分析,得出最合理的B-spline路径规划和跟踪算法。结果表明,B-spline算法在换道点和并道点曲率为0,满足换道条件的要求;MPC算法在正弦轨迹下比其他算法平均误差小约48.6%,在圆形轨迹下比其他算法平均误差小约84%,说明该算法在多种轨迹下都具有很好的跟踪性,能在一定程度上保证智能驾驶汽车的安全性和稳定性,为今后智能车辆路径规划和轨迹跟踪控制研究提供参考。 展开更多
关键词 智能驾驶 轨迹跟踪 b-spline 稳定性
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基于Simplex算法的高压直流输电分段变速率VDCOL研究 被引量:8
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作者 冯明 李兴源 +2 位作者 李妮 王超 洪潮 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2015年第4期162-167,共6页
为了改善高压直流系统的故障后的恢复性能,在研究低压限流单元(voltage dependent current order limiter,VDCOL)对直流系统无功功率消耗和电压稳定性影响的基础上,提出了一种分段变速率低压限流单元(piecewise-variable-rate VDCOL,PVR... 为了改善高压直流系统的故障后的恢复性能,在研究低压限流单元(voltage dependent current order limiter,VDCOL)对直流系统无功功率消耗和电压稳定性影响的基础上,提出了一种分段变速率低压限流单元(piecewise-variable-rate VDCOL,PVR-VDCOL)的控制方法,该方法通过将电压下降或恢复过程划分为几个不同的阶段,并在每个阶段根据电压水平的不同而设置不同的功率恢复速率。推导了控制器初值的计算公式,制定了利用Simplex算法优化控制器参数的流程,并重点分析了分段数目对控制器性能的影响及其确定方法。在PSCAD/EMTDC中对提出的PVR-VDCOL和传统线性VDCOL的控制效果进行了对比仿真,并对不同分段数目下的仿真结果进行了对比分析,仿真结果表明提出的PVR-VDCOL能够有效改善直流系统的恢复性能。 展开更多
关键词 高压直流输电 低压限流单元 电压稳定 simplex算法
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