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PERMANENCE AND GLOBAL ATTRACTIVITY OF N-SPECIES COOPERATION SYSTEM WITH DISCRETE TIME DELAYS AND FEEDBACK CONTROLS

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Annals of Differential Equations 2007年第1期23卷 18-25页

作者： he weilian College of Basic Medicine Fujian Medical University Fuzhou 350004

In this paper, we consider the N-species cooperation system with discrete time delays and feedback controls. By using the differential inequality theory and constructing a suitable Lyapunov functional, we obtain suffi... 详细信息

关键词： cooperation system permanence global attractivity discrete delays feedback controls

Investigation of Mechanisms About Effects of Promoters P_2O_5,K_2O and A1_2O_3 on Oxidation of o-Xylene to Phthalic Anhydride

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Chemical Research in Chinese Universities 1990年第2期6卷 141-148页

作者： Zheng Xiaoming, he weilian, Yuan Xianxin, Zhou Lichua and Jin Songshou (Department of Chemistry, Hangzhau University, Hangzhau)

We succeeded in designing an effective catalyst, V2O5-P2O5-K2O/Al2O3. SiO2, by which a high yield of PA,105wt% can be gained in middle-sized industrial fluidized bed apparatus without addition of any promoting *** mechanisms of effects of P2O5, K2O and Al2O3 on the surface properties of V2O5 were investigated by means of TPD and XRD. And the selectivity of oxidation are *** of a great deal of P2O5 restrains the activity of donating surface oxygen from V2O5, but increases the number of sites which donate surface oxygen. Addition of K2O promotes donation of surface oxygen from V2O6, and decreases the number of sites of donating oxygen, on the other hand, addition of K|O makes the surface structure of V2O5 catalysts more stable. Coating a small amount of Al2O2 onto support, SiO2, restrains the activity of donating oxygen and increases the number of sites of donating surface oxygen from V2O5.

关键词： Catalyst Oxidation Phthalic anhydride o-Xylene

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多种群非线性竞争反馈控制模型的概周期解

宁夏大学学报（自然科学版） 2008年第2期29卷 112-115,122页

作者：何尾莲福建医科大学基础医学院福建福州350004

研究多种群非线性竞争反馈控制模型.通过技巧性地引入一个变换,将所研究系统的概周期解存在性问题转化为新系统的概周期解的存在性问题.然后利用微分方程不等式,并通过构造适当的Lyapunov函数,获得该模型有全局吸引的概周期正解的充分条件.

关键词：竞争系统反馈控制概周期解全局吸引非线性 Lyapunov函数

基于改进粗糙集概率模型的鲁棒医学图像分割算法

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计算机应用研究 2017年第8期34卷 2546-2550,2556页

作者：吴方何尾莲福建医科大学基础医学院福州350108

基于参数化模型的图像分割算法对复杂的医学图像分割精度较低,提出一种基于改进粗糙集概率模型的鲁棒医学图像分割算法。首先,将粗糙集的上下逼近与概率边界区引入最大期望算法中,表征每个类簇;然后,将图像的灰度分布建模为一个有限数... 详细信息

基于参数化模型的图像分割算法对复杂的医学图像分割精度较低,提出一种基于改进粗糙集概率模型的鲁棒医学图像分割算法。首先,将粗糙集的上下逼近与概率边界区引入最大期望算法中,表征每个类簇;然后,将图像的灰度分布建模为一个有限数量的混合粗糙集概率分布;最终,通过马尔可夫随机场引入图像的空间信息,提高图像分割算法的鲁棒性。基于合成脑部MR(核磁共振)图像库与真实脑部MR图像库的分割实验结果显示,本算法的分割精度与鲁棒性均优于其他参数化模型的分割算法及其他专门的脑部MR图像分割算法。

关键词：粗糙集参数化模型医学图像分割最大期望算法马尔可夫随机场鲁棒性

Bioceramic scaffolds with two-step internal/external modification of copper-containing polydopamine enhance antibacterial and alveolar bone regeneration capability

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 65-82页

作者： Xiaojian JIANG Lihong LEI weilian SUN Yingming WEI Jiayin HAN Shuaiqi ZHONG Xianyan YANG Zhongru GOU Lili CheN Department of Oral Medicine the Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China Bio-nanomaterials and Regenerative Medicine Research Division Zhejiang–California International Nanosystem InstituteZhejiang UniversityHangzhou310058China

Magnesium-doped calcium silicate(CS)bioceramic scaffolds have unique advantages in mandibular defect repair;however,they lack antibacterial properties to cope with the complex oral ***,for the first time,the CS scaffold was functionally modified with a novel copper-containing polydopamine(PDA(Cu^(2+)))rapid deposition method,to construct internally modified(*P),externally modified(@PDA),and dually modified(*P@PDA)*** morphology,degradation behavior,and mechanical properties of the obtained scaffolds were evaluated in *** results showed that the CS*P@PDA had a unique micro-/nano-structural surface and appreciable mechanical *** the prolonged immersion stage,the release of copper ions from the CS*P@PDA scaffolds was rapid in the early stage and exhibited long-term sustained *** in vitro evaluation revealed that the release behavior of copper ions ascribed an excellent antibacterial effect to the CS*P@PDA,while the scaffolds retained good cytocompatibility with improved osteogenesis and angiogenesis ***,the PDA(Cu^(2+))-modified scaffolds showed effective early bone regeneration in a critical-size rabbit mandibular defect ***,it was indicated that considerable antibacterial property along with the enhancement of alveolar bone regeneration can be imparted to the scaffold by the two-step PDA(Cu^(2+))modification,and the convenience and wide applicability of this technique make it a promising strategy to avoid bacterial infections on implants.

关键词： Copper-containing polydopamine Modification Antibacterial property Bone regeneration Angiogenesis Bioceramic scaffold

动力荷载作用下杆系钢结构节点疲劳裂纹扩展断裂破坏的分析方法

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土木工程学报 2010年第12期43卷 78-86页

作者：瞿伟廉何钟山刘嘉武汉理工大学湖北武汉430070

基于ANSYS有限元计算软件,提出杆系钢结构节点疲劳裂纹扩展断裂破坏的分析方法。首先介绍杆系钢结构节点子结构的多尺度有限元计算方法的原理和含三维裂纹节点子结构的有限元建模方法。其次提出疲劳裂纹扩展实时应力强度因子的计算方法... 详细信息

基于ANSYS有限元计算软件,提出杆系钢结构节点疲劳裂纹扩展断裂破坏的分析方法。首先介绍杆系钢结构节点子结构的多尺度有限元计算方法的原理和含三维裂纹节点子结构的有限元建模方法。其次提出疲劳裂纹扩展实时应力强度因子的计算方法及通过对节点子结构荷载边界条件采用分组的方式计算出多轴非比例加载情况下的应力强度因子幅的方法。再次通过Paris裂纹扩展公式完成裂纹扩展的疲劳寿命计算。最后通过一个铁路钢桁架桥工程实例的详细分析,得到其节点区疲劳裂纹扩展的全过程,并对此桥的疲劳寿命进行预测。

关键词：杆系钢结构节点裂纹扩展应力强度因子多轴非比例加载疲劳寿命

Aloe emodin promotes mucosal healing by modifying the differentiation fate of enteroendocrine cells via regulating cellular free fatty acid sensitivity

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3964-3982页

作者： weilian Bao Jiaren Lyu Guize Feng Linfeng Guo Dian Zhao Keyuan You Yang Liu Haidong Li Peng Du Daofeng Chen Xiaoyan Shen Department of Pharmacology&the Key Laboratory of Smart Drug Delivery Ministry of Education School of PharmacyFudan UniversityShanghai 201210China Department of Natural Medicine School of PharmacyFudan UniversityShanghai 201210China Department of Colorectal and Anal Surgery Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Shanghai Colorectal Cancer Research Center Shanghai 200092China

The proper differentiation and reorganization of the intestinal epithelial cell population is critical to mucosal regeneration post *** retaining cells(LRCs)expressing SRY-box transcription factor 9(SOX9)promote epithelial repair by replenishing LGR5 t intestinal stem cells(ISCs).While,LRCs are also considered precursor cells for enteroendocrine cells(EECs)which exacerbate mucosal damage in inflammatory bowel disease(IBD).The factors that determine LRC-EEC differentiation and the effect of intervening in LRC-EEC differentiation on IBD remain *** this study,we investigated the effects of a natural anthraquinone called aloe emodin(derived from the Chinese herb rhubarb)on mucosal healing in IBD *** findings demonstrated that aloe emodin effectively interfered with the differentiation to EECs and preserved a higher number of SOX9t LRCs,thereby promoting mucosal ***,we discovered that aloe emodin acted as an antagonist of free fatty acid receptors(FFAR1),suppressing the FFAR1-mediated Gbg/serine/threonine-protein kinase(AKT)pathway and promoting the translocation of forkhead box protein O1(FOXO1)into the nucleus,ultimately resulting in the intervention of differentiation *** findings reveal the effect of free fatty acid accessibility on EEC differentiation and introduce a strategy for promoting mucosal healing in IBD by regulating the FFAR1/AKT/FOXO1 signaling pathway.

关键词： LRCs ISCs EECs IBD SOX9 Aloe emodin FFAR1 FOXO1

离合器波形片特性对机械变速器乘用车起步颤振影响的研究

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传动技术 2015年第1期29卷 20-24页

作者：陈达何维廉上海交通大学机械与动力工程学院上海200240

为了改善车辆起步行驶时由于离合器波形片不平稳引起的整车颤振现象,对传动系统及离合器波形片工作过程进行数学建模,提出相应的改善措施,并进行了验证性仿真实验。仿真结果表明,通过改善波形片的结构,可以明显地改善车辆起步颤振现象... 详细信息

为了改善车辆起步行驶时由于离合器波形片不平稳引起的整车颤振现象,对传动系统及离合器波形片工作过程进行数学建模,提出相应的改善措施,并进行了验证性仿真实验。仿真结果表明,通过改善波形片的结构,可以明显地改善车辆起步颤振现象。在实际中,试验结果验证了改善措施的正确性和可行性。

关键词：离合器波形片 Judder起步颤振

基于虚拟仿真与翻转课堂项目教学法在单片机课程中的应用

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福建医科大学学报（社会科学版） 2022年第1期23卷 71-75页

作者：吴方何尾莲福建医科大学文理艺术学院福建福州350122

以福建医科大学为例,分析单片机教学中的问题,引入虚拟仿真工具(Proteus),并采用翻转课堂教学模式和设计教学项目构建教学法,通过案例讨论说明教学法的实施并进行效果分析。问卷调查结果显示,基于虚拟仿真与翻转课堂的项目教学法能够提... 详细信息

以福建医科大学为例,分析单片机教学中的问题,引入虚拟仿真工具(Proteus),并采用翻转课堂教学模式和设计教学项目构建教学法,通过案例讨论说明教学法的实施并进行效果分析。问卷调查结果显示,基于虚拟仿真与翻转课堂的项目教学法能够提升教学质量,激发学生积极性和主动性,培养学生理论与实践相结合的能力,考核方式能有效引导学生的学习。因此,建议高校开展同类课程时应通过丰富视频资料和增加不同难度的教学项目等手段进一步提升教学效果。

关键词：虚拟仿真翻转课堂项目教学法单片机