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薄板系统振动主动控制器的一种设计(英文)

控制理论与应用 2000年第3期17卷 353-357页

作者：李奕阳任礼行梁天培香港理工大学机械工程系

根据基于模型的模糊控制策略 ,提出一种薄板系统振动主动控制器的设计 .与传统的方法不同之处在于作者首先采用递归的RAMAX算法和PEM进行模糊参数识别 ,从而建模 ;其次 ,通过在线调整系数矩阵Θ(α)的元素和目标函数优化 ,进行自适应控... 详细信息

根据基于模型的模糊控制策略 ,提出一种薄板系统振动主动控制器的设计 .与传统的方法不同之处在于作者首先采用递归的RAMAX算法和PEM进行模糊参数识别 ,从而建模 ;其次 ,通过在线调整系数矩阵Θ(α)的元素和目标函数优化 ,进行自适应控制器合成 .数值仿真和实验结果验证了本文所提方法的有效性和鲁棒性 .

关键词：振动主动控制器模糊建模薄板系统自适应控制

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三维柔性多体梁系统非线性动力响应分析

振动与冲击 2006年第1期25卷 24-27页

作者：吴国荣钟伟芳梁以德福建工程学院土木系福州350007 华中科技大学力学系武汉430074

研究了三维柔性多体梁系统的非线性动力响应问题。将空间柔性梁的变形分解为轴向变形以及在x-y平面的弯曲变形和在x-z平面的弯曲变形,引用各自的精确振动模态描述变形场,利用拉格朗日乘子法建立起柔性多体梁系统约束非线性动力学方程。... 详细信息

研究了三维柔性多体梁系统的非线性动力响应问题。将空间柔性梁的变形分解为轴向变形以及在x-y平面的弯曲变形和在x-z平面的弯曲变形,引用各自的精确振动模态描述变形场,利用拉格朗日乘子法建立起柔性多体梁系统约束非线性动力学方程。结合Newm ark直接积分法和Newton-Raphson迭代法,导出了求解该非线性代数-微分方程组的数值方法。仿真算例证明了该方法的正确性和有效性。

关键词：多体系统三维柔性梁非线性动力响应

强Van der Pol振子的谐波与修正算法

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大学物理 2009年第3期28卷 4-7页

作者：国忠金梁以德马晓燕泰山学院数学与系统科学系山东泰安271021 香港城市大学建筑工程系

引入谐波平衡近似解的符号运算与同伦延拓法,获得了强Van der Pol振子的解析近似极限环与稳定响应.为提高其近似精度,给出了谐波解的修正算法,并与数值模拟比较.结果表明,该算法非常精确可靠,是研究强非线性动力学系统的有效分析方法.

关键词：谐波平衡同伦延拓法修正算法极限环

Lymph node harvest in colon and rectal cancer:Current considerations

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World Journal of Gastrointestinal Surgery 2012年第1期4卷 9-19页

作者： James R McDonald andrew G Renehan Sarah t O’Dwyer Najib y Haboubi Department of Surgery The Christie NHS Foundation Trust School of Cancer and Enabling Sciences University of ManchesterManchester Academic Health Sciences CentreThe Christie NHS Foundation Trust Department of Histopathology University Hospital of South Manchester

the prognostic significance of identifying lymph node (LN) metastases following surgical resection for colon and rectal cancer is well recognized and is reflected in accurate staging of the disease. An established body of evidence exists, demonstrating an association between a higher total LN count and improved survival, particularly for node negative colon cancer. In node positive disease, however, the lymph node ratios may represent a better prognostic indicator, although the impact of this on clinical treatment has yet to be universally established. By extension, strategies to increase surgical node harvest and/or laboratory methods to increase LN yield seem logical and might improve cancer staging. However, debate prevails as to whether or not these extrapolations are clinically relevant, particularly when very high LN counts are sought. Current guidelines recommend a minimum of 12 nodes harvested as the standard of care, yet the evidence for such is questionable as it is unclear whether an increasing the LN count results in improved survival. Findings from modern treatments, including down-staging in rectal cancer using pre-operative chemoradiotherapy, paradoxically suggest that lower LN count, or indeed complete absence of LNs, are associated with improved survival; implying that using a specific number of LNs harvested as a measure of surgical quality is not always appropriate. the pursuit of a sufficient LN harvest represents good clinical practice; however, recent evidence shows that the exhaustive searching for very high LN yields may be unnecessary and has little influence on modern approaches to treatment.

关键词： Colon cancer Rectal cancer Lymph node Quality indicator Survival

Effects of Ving tsun sticking-hand training on upper-limb sensorimotor performance in community-dwelling middle-aged and older adults: A randomized controlled trial

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International Journal of Nursing Sciences 2020年第1期7卷 29-34页

作者： Joanne W.y.Chung Shirley S.M.Fong yang Gao timothy t.t.yam yvonne t.C.Chak Joyce C.y.leung thomas K.S.Wong Department of Health and Physical Education Education University of Hong KongHong KongChina School of Nursing and Healthcare Hong Kong Nang Yan College of Higher EducationHong KongChina Hong Kong Martial Arts Institute Hong KongChina School of Public Health University of Hong KongHong KongChina Department of Sport and Physical Education Hong Kong Baptist UniversityHong KongChina Hong Kong Christian Service Hong KongChina School of Nursing and Health Studies Open University of Hong KongHong KongChina Department of Social Work and Social Administration University of Hong KongHong KongChina

Objective:to evaluate the effects of Ving tsun(Vt)sticking-hand training on upper-limb joint position sense and muscular performance in community-dwelling middle-aged and older ***:thirty-three adults were randomly allocated to either a Vt group or a control *** Vt group received Vt sticking-hand training twice per week for 3 *** were taken before and after the intervention *** primary outcome was elbow-joint repositioning error,which was measured by an elbow-joint passive positioning and active repositioning test using a universal *** outcomes were upper-limb muscles'peak force and time taken to reach peak force as measured by a hand-held ***:No significant time,group or time-by-group interaction effects were found for elbow-joint repositioning error or upper-limb muscle peak force *** flexor time to peak force decreased by 33.8%from pre-test to post-test in the Vt group(P=0.007).Shoulder abductor,internal and external rotator,and elbow extensor times to peak force decreased by 30.0%-35.9%in the Vt%roup(Py 30.4%-37.1%in the control group(Pt sticking-hand training does not improve elbow-joint position sense or the maximum strength of upper-limb muscles in middle-aged and older ***,Vt can improve shoulder flexor muscles'time to reach peak force in these *** had no obvious effect on the time required to reach peak force in other shoulder muscles and elbow extensors.

关键词： Aged Exercise movement techniques Joint position sense Middle aged Muscle strength Upper extremities

二维弹性平面问题中任意边界条件下应力分布的封闭解

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应用数学和力学 2007年第12期28卷 1455-1467页

作者：梁以德郑建军香港城市大学建筑系

应用辛方法研究了正交各向异性二维平面(x,z)弹性问题,在任意边界和不考虑梁假设条件下的解析应力分布解.辛方法通过将位移和应力作为对偶量推导得到一组辛的偏微分方程组,并且应用变量分离法对方程组进行了求解.同动力学中的问题比较,... 详细信息

应用辛方法研究了正交各向异性二维平面(x,z)弹性问题,在任意边界和不考虑梁假设条件下的解析应力分布解.辛方法通过将位移和应力作为对偶量推导得到一组辛的偏微分方程组,并且应用变量分离法对方程组进行了求解.同动力学中的问题比较,将弹性问题中的x轴模拟成时间轴,这样z轴成为唯一一个独立的坐标轴.问题中的Hamilton矩阵的指数展开具有辛的特征.在齐次问题求解中,通过边界条件和边界上的积分求得级数中的未知数.齐次解中包括减阶的零特征值的特征向量(零本征向量)和完好的非零本征值的特征向量(非零本征向量).零本征值的Jordan链给出了经典的Saint Venant解,反映了平均的整体行为像刚体位移、刚体旋转和弯曲等.另外,非零本征向量反映的是指数衰减的局部解,它们通常在Saint Venant原理下被忽略.文中给出了完整的算例,并且和已有结果进行了对比.

关键词：横观各向同性特征函数辛展开

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利用能量原理研究单壁碳纳米管的剪切模量

华中科技大学学报（自然科学版） 2006年第11期34卷 110-112页

作者：吴永东张小春钟伟芳梁以德华中科技大学土木工程与力学学院湖北武汉430074 香港城市大学建筑系

利用能量方法研究了单壁碳纳米管(SWCNt)的剪切模量.采用分子力学理论得出了受扭矩作用下单壁碳纳米管的总势能;通过总势能与相应的薄壁圆筒的扭转变形能比较,推导出了单壁碳纳米管剪切模量的计算公式;碳纳米管剪切模量的计算结果与现... 详细信息

利用能量方法研究了单壁碳纳米管(SWCNt)的剪切模量.采用分子力学理论得出了受扭矩作用下单壁碳纳米管的总势能;通过总势能与相应的薄壁圆筒的扭转变形能比较,推导出了单壁碳纳米管剪切模量的计算公式;碳纳米管剪切模量的计算结果与现有的研究结果相符,从而证实了本文计算公式正确有效.

关键词：单壁碳纳米管剪切模量能量原理

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信息理论与气候预报

气象科技 1991年第3期19卷 23-31页

作者： L-y.leung G.R.North 朱复成

本文把信息理论引入到刻划气候可预报性中,特别是借用了熵和信息传递(transinformation)的概念。熵定量地表示了我们对气候系统状态了解的不确定性。信息传递代表了在已知初始距平大小的情况下,在任意时刻t获得的关于这一距乎的信息。... 详细信息

本文把信息理论引入到刻划气候可预报性中,特别是借用了熵和信息传递(transinformation)的概念。熵定量地表示了我们对气候系统状态了解的不确定性。信息传递代表了在已知初始距平大小的情况下,在任意时刻t获得的关于这一距乎的信息。信息传递有许多吸引人的性质,能用来作气候系统可预报性的一种量度。通过一个简单的随机气候模式(一个受噪声强迫的能量平衡模式)对这些概念如何用于气候可预报性作了解释。尽管我们对初始状态有充分了解,但研究表明信息传递描述了关于距平的信息衰减。本文还特别对把信息传递推广到其他气候模式时的用途作了讨论。

关键词：距平可预报性气候模式气候系统气候预报信息理论信息传递能量平衡模式预报模式气候研究

Penetrating Ocular trauma in a Goldfish Model after Chloramphenicol or traditional Medicine Angong Niuhuang Pill treatment: An Analysis of Retinal Responses after 7 Days

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Open Journal of Ophthalmology 2022年第3期12卷 294-306页

作者： Rufina S. y. Cheng Gigi C. t. leung tony C. H. Chow Jocy t. C. Lee Sharon L. y. Wu Linda S. L. Wu David t. yew School of Chinese Medicine Faculty of Medicine The Chinese University of Hong Kong Shatin China Hong Kong College of technology Shatin China School of Biomedical Sciences Faculty of Medicine The Chinese University of Hong Kong Shatin China

Purpose: While there were numerous clinical examples of ocular damage, the histopathology of retinal responses was poorly characterized, and animal model research was limited. the consequences of retinal lesions with traditional medicine treatment were mostly unknown. In this work, goldfish was employed as a model for penetrating injury of the eyes to study the ocular trauma with antibiotic and traditional medicine treatments. Materials and Methods: the penetration of the eyes was performed at 2mm above the midline of the limbus in the superior quadrant with an 18-gauge sterile needle, all the way to the retina but avoiding the lens while the animals were anaesthetized in water containing 100 mg/L ethyl 3-aminobenzoate methanesulfonate (MS-222). the animals were divided into three groups and received treatments of saline, chloramphenicol, and Angong Niuhuang pill (Angong) eyedrops twice a day respectively. Angong after seven days, the animals were sacrificed. Immunohistochemical evaluation of proliferative cell nuclear antigen (PCNA), brain-derived neurotrophic factor (BDNF), catalase, and cleaved caspase-3, and terminal deoxynucleotidyl transferase dUtP nick end labeling (tUNEL) for apoptotic cells were performed on the fish’s superior quadrants of the retinae. the whole experiment was repeated two times. Result: It was evident that both the retinae treated with chloramphenicol and Angong had fewer apoptotic cells and more proliferative cells, particularly in the cases of the Angong treatment. BDNF was in the inner nuclear layer and ganglion cell layer of all groups. In the chloramphenicol and Angong groups, some cells in the outer nuclear layer displayed BDNF. Catalase reactions confirmed equivalent findings that the treated retinae with chloramphenicol or Angong treatment had less catalase. Conclusion: Angong Niuhuang pill is a traditional medicine composite formula with antibiotic and neuroprotective effects on the brain and the eyes, and this work also pointed

关键词： Ocular trauma Goldfish Chloramphenicol traditional Medicine Angonggong Niuhuang Pill