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Ascophyllum nodosum and Fucus vesiculosus ameliorate restenosis via improving inflammation and regulating the PTEN/PI3K/AKT signaling pathway
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作者 Crystal Ngofi Zumbi Chun-Hsu Pan +1 位作者 Hui-Yu Huang Chieh-Hsi Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1711-1728,共18页
Restenosis is a common complication following coronary angioplasty.The traditional use of seaweeds for health benefits has increasingly been explored,however few studies exist reporting its protective effects on the d... Restenosis is a common complication following coronary angioplasty.The traditional use of seaweeds for health benefits has increasingly been explored,however few studies exist reporting its protective effects on the development of restenosis and gut dysbiosis.The aim of this study was to investigate the potential of seaweed extracts(SE) of Ascophyllum nodosum and Fucus vesiculosus in inhibiting intimal hyperplasia in a rat model of restenosis and its underlying mechanisms in macrophages and vascular smooth muscle cells(vSMCs).16S rRNA sequencing was done to investigate the regulatory effect of SE on the gut microbiome of injured rats.As indicated by the results,SE significantly inhibited the progression of intimal hyperplasia in vivo,attenuated inflammation in macrophages and could inhibit the proliferation,dedifferentiation and migration of vSMCs.It was observed through immunoblotting assays that treatment with SE significantly upregulated PTEN expression in macrophages and inhibited the upregulation of PI3K and AKT expression in vSMCs.Meanwhile,according to the 16S rRNA gene sequencing analysis,supplementation with SE modulated gut microbiota composition in injured rats.In conclusion,SE could ameliorate intimal hyperplasia by inhibiting inflammation and vSMCs proliferation through the regulation of the PTEN/PI3K/AKT pathway and modulating the gut microbiome. 展开更多
关键词 Ascophyllum nodosum Fucus vesiculosus PTEN/PI3k/AkT RESTENOSIS MACROPHAGE Vascular smooth muscle cells Gut microbiota
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Notes of k-smoothness in Orlicz sequence spaces
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作者 刘春燕 石忠锐 《Journal of Shanghai University(English Edition)》 CAS 2010年第6期420-423,共4页
The criterion for k-smooth points of the Orlicz sequence space endowed with the Orlicz norm is proved. The necessary and sufficient conditions of k-smoothness of l M and l (M ) are obtained, respectively. Finally, w... The criterion for k-smooth points of the Orlicz sequence space endowed with the Orlicz norm is proved. The necessary and sufficient conditions of k-smoothness of l M and l (M ) are obtained, respectively. Finally, we give the counterexamples which show that previous results are not true. 展开更多
关键词 Orlicz sequence space k-smoothness k-smooth point Orlicz norm Luxemburg norm
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Equivalence between Modulus of Smoothness and K-Functional on Rotation Group SO(3)
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作者 Zhuyuan Yang Zongwen Yang 《Journal of Applied Mathematics and Physics》 2017年第2期341-345,共5页
In this paper we obtain the equivalence between modulus of smoothness and K-functional on rotation group SO(3).
关键词 ROTATION GROUP MODULUS of smoothness k-FUNCTIONAL EQUIVALENCE
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Equivalence of <i>K</i>-Functionals and Modulus of Smoothness Generated by a Generalized Dunkl Operator on the Real Line
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作者 Reem Fahad Al Subaie Mohamed Ali Mourou 《Advances in Pure Mathematics》 2015年第6期367-376,共10页
This paper is intended to establish the equivalence between K-functionals and modulus of smoothness tied to a Dunkl type operator on the real line.
关键词 Differential-Difference Operator GENERALIZED Fourier Transform GENERALIZED Translation Operators k-Functionals MODULUS of smoothness
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Effects of Mitochondrial ATP-sensitive K^+ Channel on Protein Kinase C Pathway and Airway Smooth Muscle Cell Proliferation in Asthma 被引量:4
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作者 万璇 赵建平 谢俊刚 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第4期480-484,共5页
The effects of ATP-sensitive mitochondrial K + channel(mitoK ATP) on mitochondrial membrane potential(Δψm),cell proliferation and protein kinase C alpha(PKCα) expression in airway smooth muscle cells(ASMCs) were in... The effects of ATP-sensitive mitochondrial K + channel(mitoK ATP) on mitochondrial membrane potential(Δψm),cell proliferation and protein kinase C alpha(PKCα) expression in airway smooth muscle cells(ASMCs) were investigated.Thirty-six Sprague-Dawley(SD) rats were immunized with saline(controls) or ovalbumin(OVA) with alum(asthma models).ASMCs were cultured from the lung of control and asthma rats.ASMCs were treated with diazoxide(the potent activator of mitoK ATP) or 5-hydroxydencanote(5-HD,the inhibitor of mitoK ATP).Rhodamine-123(R-123) was used to detect Δψm.The expression of PKCα protein was examined by using Western blotting,while PKCα mRNA expression was detected by using real-time PCR.The proliferation of ASMCs was measured by MTT assay and cell cycle analysis.In diazoxide-treated normal ASMCs,the R-123 fluorescence intensity,protein and mRNA levels of PKCα,MTT A values and percentage of cells in S phase were markedly increased as compared with untreated controls.The ratio of G 0 /G 1 cells was decreased(P<0.05) in diazoxide-treated ASMCs from normal rats.However,there were no significant differences between the ASMCs from healthy rats treated with 5-HD and the normal control group.In untreated and diazoxide-treated ASMCs of asthmatic rats,the R-123 fluorescence intensity,protein and mRNA levels of PKCα,MTT A values and the percentage of cells in S phase were increased in comparison to the normal control group.Furthermore,in comparison to ASMCs from asthmatic rats,these values were considerably increased in asthmatic group treated with diazoxide(P<0.05).After exposure to 5-HD for 24 h,these values were decreased as compared with asthma control group(P<0.05).In ASMCs of asthma,the signal transduction pathway of PKCα may be involved in cell proliferation,which is induced by the opening of mitoK ATP and the depolarization of Δψm. 展开更多
关键词 ASTHMA airway smooth muscle cells ATP-sensitive k + channel protein kinase C
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Strong ground motion simulation for the 2013 Lushan M_W6.6 earthquake, Sichuan, China, based on the inverted and synthetic slip models 被引量:1
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作者 Wenhao Shen Qiu Zhong Baoping Shi 《Earthquake Science》 2014年第4期377-389,共13页
It is well known that quantitative estimation of slip distributions on fault plane is one of the most important issues for earthquake source inversion related to the fault rupture process. The characteristics of slip ... It is well known that quantitative estimation of slip distributions on fault plane is one of the most important issues for earthquake source inversion related to the fault rupture process. The characteristics of slip distribution on the main fault play a fundamental role to control strong ground motion pattern. A large amount of works have also suggested that variable slip models inverted from longer period ground motion recordings are relevant for the prediction of higher frequency ground motions. Zhang et al. (Chin J Geophys 56:1412-1417, 2013) and Wang et al. (Chin J Geophys 56:1408-1411,2013) published their source inversions for the fault rupturing process soon after the April 20, 2013 Lushan earthquake in Sichuan, China. In this study, first, we synthesize two forward source slip models: the value of maximum slip, fault dimension, size, and dimension of major asperities, and comer wave number obtained from Wang's model is adopted to constrain the gen- eration of k-2 model and crack model. Next, both inverted and synthetic slip models are employed to simulate the ground motions for the Lushan earthquake based on the stochastic finite-fault method. In addition, for a comparison purpose, a stochastic slip model and another k-2 model (k 2 model II) with 2 times value of comer wave number of the original k-2 model (k 2 model I) are also employed for simulation for Lushan event. The simulated results characterized by Modified Mer- calli Intensity (MMI) show that the source slip models based on the inverted and synthetic slip distributions could capture many basic features associated with the ground motion patterns. Moreover, the simulated MMI distributions reflect the rupture directivity effect and the influence of the shallow velocity structure well. On the other hand, the simulated MMI bystochastic slip model and k 2 model II is apparently higher than observed intensity. By contrast, our simulation results show that the higher frequency ground motion is sensitive to the degree of slip roughness; therefore, we suggest that, for realistic ground- motion simulations due to future earthquake, it is imperative to properly estimate the slip roughness distribution. 展开更多
关键词 Stochastic finite-fault model strong groundmotion -2013 Lushan Mw6.6 earthquake Corner wavenumber k -2 model Crack model
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Effects of Atractylodes Macrocephala on the Cytomembrane Ca^(2+)-activated K^+ Currents in Cells of Human Pregnant Myometrial Smooth Muscles 被引量:2
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作者 章小莉 汪琳 +1 位作者 徐龙 邹丽 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第2期200-203,共4页
The study examined the inhibitory effect of Atractylodes macrocephala (AM) on the uterine contraction during premature delivery and explored its electrophysiological mechanism by studying the effects of AM on the C... The study examined the inhibitory effect of Atractylodes macrocephala (AM) on the uterine contraction during premature delivery and explored its electrophysiological mechanism by studying the effects of AM on the Ca^2+-activated K^+ currents of pregnant human myometrial smooth muscle cells with or without the treatment with intedeukin-6. Single cells were acutely isolated from pregnant human myometrial smooth muscles. Whole-cell Ca^2+-activated K^+ currents were recorded by using an Axopatchl-D amplifier. The cells were divided into three groups: group A in which AM was added into perfusate, group B, in which interleukin-6 was added into perfusate) and group C in which AM was added into perfusate after addition of interleukin-6. IL-6 10 ng/mL inhibited BKca by 36.9%±13.7% as compared with control (P〈0.01). AM at 2 mg/mL raised BKca by 36.7%±22.6% or 45.2%±13.7% with or without the treatment of IL-6, respectively (P〈0.01). It is concluded that AM was able to enhance the BKca of pregnant human myometrial smooth muscle cells treated or untreated with interleukin-6 and its effect on the BKca IL-treated cells was stronger that its effect on BKca of untreated cells. Our results suggested that AM can help to maintain the membrane potentials and the resting status of pregnant human myometrial smooth muscle cells. 展开更多
关键词 atractylodes macrocephala INTERLEUkIN-6 patch clamp Ca^2+-activated k^+ currents myometrial smooth muscle cells premature delivery
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K^+ Channels and Their Effects on Membrane Potential in Rat Bronchial Smooth Muscle Cells
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作者 刘先胜 徐永健 +1 位作者 张珍祥 倪望 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第2期141-144,150,共5页
In order to investigate the K+ channels and their effects on resting membrane potential (Em) and excitability in rat bronchial smooth muscle cells (BSMCs), the components of outward K+ channel currents and the effects... In order to investigate the K+ channels and their effects on resting membrane potential (Em) and excitability in rat bronchial smooth muscle cells (BSMCs), the components of outward K+ channel currents and the effects of K+ channels on Em and tension in rat bronchial smooth muscle were observed by using standard whole-cell recording of patch clamp and isometric tension recording techniques. The results showed that under resting conditions, total outward K+ channel currents in freshly isolated BSMCs were unaffected by ATP-sensitive K+ channel blocker. There were two types of K+ currents: voltage-dependent delayed rectifier K+ channel (Kv) and large conductance calcium-activated K+ channel (BKc.) currents. 1 mmol/L 4-aminopyridine (4-AP, an inhibitor of Kv) caused a significant depolarization (from -8. 7±5. 9 mV to -25. 4±3. 1 mV, n=18, P<0. 001). In contrast, 1 mmol/L tetraethylammonium (TEA, an inhibitor of BKc.) had no significant effect on Em (from -37. 6±4. 8 mV to -36. 8±4.1mV, n=12, P>0. 05). 4-AP caused a concentration-dependent contraction in resting bronchial strips. TEA had no effect on resting tension, but application of 5 mmol/L TEA resulted in a left shift with bigger pD2(the negative logarithm of the drug concentration causing 50% of maximal effect) (from 6. 27±0. 38 to 6. 89±0. 54, n= 10, P<0. 05) in the concentration-effect curve of endothine-1, and a right shift with smaller pD2(from 8. 10±0. 23 to 7. 69±0. 08, n=10, P<0. 05) in the concentration-effect curve of isoprenaline. It was suggested that in rat BSMCs there may be two types of K+ channels, Kv and BKca, which serve distinct roles. Kv participates in the control of resting Em and tension. BKca is involved in the regulation of relaxation or contraction associated with excitation. 展开更多
关键词 airway smooth muscle cells k+ channel membrane potential
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Prediction of near-field strong ground motions for scenario earthquakes on active fault
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作者 王海云 谢礼立 +1 位作者 陶夏新 李捷 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2006年第1期11-17,共7页
A method to predict near-field strong ground motions for scenario earthquakes on active faults is proposed. First, macro-source parameters characterizing the entire source area, i.e., global source parameters, includi... A method to predict near-field strong ground motions for scenario earthquakes on active faults is proposed. First, macro-source parameters characterizing the entire source area, i.e., global source parameters, including fault length, fault width, rupture area, average slip on the fault plane, etc., are estimated by seismogeology survey, seismicity and seismic scaling laws. Second, slip distributions characterizing heterogeneity or roughness on the fault plane, i.e., local source parameters, are reproduced/evaluated by the hybrid slip model. Finally, the finite fault source model, developed from both the global and local source parameters, is combined with the stochastically synthetic technique of ground motion using the dynamic comer frequency based on seismology. The proposed method is applied to simulate the acceleration time histories on three base-rock stations during the 1994 Northridge earthquake. Comparisons between the predicted and recorded acceleration time histories show that the method is feasible and practicable. 展开更多
关键词 active fault scenario earthquake near-field strong ground motion global source parameters local source parameters asperity model k square slip model.
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Iterative Approximation of Fixed Points for Uniformly Continuous and Strongly Pseudocontractive Mappings in Smooth Banach Spaces
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作者 周海云 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期42-46, ,共5页
With an inequality and some analysis techniques,iterative approximation of fixed points for uniformly continuous and strongly pseudocontractive mappings in smooth Banach spaces is studied,and the recent corresponding ... With an inequality and some analysis techniques,iterative approximation of fixed points for uniformly continuous and strongly pseudocontractive mappings in smooth Banach spaces is studied,and the recent corresponding results of Chidume are improved. 展开更多
关键词 Ishikawa iteration process strong pseudocontraction strongly accretive mapping smooth Banach space
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Strong Converse Inequality for the Meyer-Knig and Zeller-Durrmeyer Operators
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作者 QI QIU-LAN LIU JUAN 《Communications in Mathematical Research》 CSCD 2012年第1期1-9,共9页
In this paper we give a strong converse inequality of type B in terms of unified K-functional Kλα (f, t2) (0 ≤λ≤ 1, 0 〈 α 〈 2) for the Meyer-Knig and Zeller-Durrmeyer type operators.
关键词 Meyer-konig and Zeller-Durrmeyer type operator moduli of smooth-ness k-functional strong converse inequality HOder's inequality
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云环境下一种强隐私保护的安全Top-k查询方案
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作者 崔韶刚 尹辉 周春光 《吉首大学学报(自然科学版)》 CAS 2023年第3期13-28,共16页
在一个多用户应用场景下,为了防止云勾结一个数据拥有者或一个数据使用者对授权用户的查询隐私进行合谋攻击,构建了云计算环境下针对查询隐私的合谋威胁模型,并实现了一种高效的强隐私保护查询方案.方案采用动态的安全查询索引结构,该... 在一个多用户应用场景下,为了防止云勾结一个数据拥有者或一个数据使用者对授权用户的查询隐私进行合谋攻击,构建了云计算环境下针对查询隐私的合谋威胁模型,并实现了一种高效的强隐私保护查询方案.方案采用动态的安全查询索引结构,该结构可以保证外包数据的安全性,且适用于数据文件频繁动态更新的多用户环境,极大地提高了系统的可伸缩性和可用性.为了满足用户的个性化查询需求,依据关键字权重对查询结果进行秘密相关性排序,实现了安全的top-k查询. 展开更多
关键词 云计算 安全索引 隐私保护 TOP-k查询
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学习理论中核函数逼近的Jackson型不等式
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作者 田明党 盛宝怀 《应用数学》 北大核心 2023年第4期903-914,共12页
从微分算子角度理解核函数空间,借助经典Fourier变换研究核函数逼近问题.应用Fourier乘子算子和算子半群定义了一种光滑模,证明其与一种基于微分算子的K-泛函的等价性,由此给出了刻画核函数逼近收敛性的Jackson不等式.进一步证明,如果... 从微分算子角度理解核函数空间,借助经典Fourier变换研究核函数逼近问题.应用Fourier乘子算子和算子半群定义了一种光滑模,证明其与一种基于微分算子的K-泛函的等价性,由此给出了刻画核函数逼近收敛性的Jackson不等式.进一步证明,如果微分算子为Riesz势算子或Bessel势算子,逼近的收敛性可以转化为卷积算子逼近.特别地,给出了再生核Hilbert空间逼近的一种上界估计. 展开更多
关键词 Jackson不等式 k-泛函 光滑模 再生核HILBERT空间 Riesz势算子 POISSON核 学习理论
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基于L0梯度平滑与图像分块聚类的海天线检测 被引量:1
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作者 郑兵 董超 +2 位作者 胡海驹 陈焱琨 刘蔚 《应用海洋学学报》 CAS CSCD 北大核心 2024年第1期106-115,共10页
海天线检测在海洋工程安防活动中具有重要的意义,真实海洋环境中的海天线检测易受云朵、海浪、光照变化、目标遮挡物、边界模糊等外界干扰。为了实现对真实海洋环境中海天线的检测,本研究提出一种基于L0梯度平滑和图像分块聚类的海天线... 海天线检测在海洋工程安防活动中具有重要的意义,真实海洋环境中的海天线检测易受云朵、海浪、光照变化、目标遮挡物、边界模糊等外界干扰。为了实现对真实海洋环境中海天线的检测,本研究提出一种基于L0梯度平滑和图像分块聚类的海天线检测算法。首先,对图像进行L0梯度平滑滤波,以增强海天线边缘,弱化非海天线因素干扰;接着,将图像沿着竖直方向分割成若干等宽图像块,以降低整体环境干扰,加强局部海天线检测效果;然后,通过Canny算子和霍夫变换提取每个分割图像块中的直线段;最后,采取K-means聚类算法提取每个图像块中的海天线段,拟合生成完整海天线。实验结果表明,在真实的海天线数据集中,本研究方法获取的矩形框重叠率平均精度为93.22%,角度差平均精度为7.66%,均高于文中选取的近年典型对比算法。满足实际海天线检测抗干扰强、准确率高、适应性广等要求。 展开更多
关键词 海洋水文学 海天线检测 L0梯度平滑滤波 图像分块 k-means线段聚类
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K一致极凸空间与K一致极光滑空间 被引量:10
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作者 吴红霞 苏雅拉图 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2004年第4期371-376,共6页
引进K一致极凸空间与K一致极光滑空间的概念,它们分别是一致极凸空间与一致极光滑空间的推广.证明了K一致极凸性与K一致极光滑性具有对偶性质,即X 为K一致极凸(K一致极光滑)的,当且仅当X为K一致极光滑(K一致极凸)的;给出了K一致极凸(K... 引进K一致极凸空间与K一致极光滑空间的概念,它们分别是一致极凸空间与一致极光滑空间的推广.证明了K一致极凸性与K一致极光滑性具有对偶性质,即X 为K一致极凸(K一致极光滑)的,当且仅当X为K一致极光滑(K一致极凸)的;给出了K一致极凸(K一致极光滑)空间的3个特征刻画;证明了K一致极凸(K一致极光滑)蕴涵(K+1)一致极凸((K+1)一致极光滑),但反过来不成立;引进K-(WM) 性质,并利用K一致极光滑给出了自反的局部K一致光滑空间的特征刻画;证明了X 为局部K一致光滑,当且仅当X为K一致极凸且具有K-(WM)性质;证明了严格凸(光滑)的K一致极凸(K一致极光滑)空间是极凸(极光滑)空间. 展开更多
关键词 光滑空间 特征刻画 一致光滑 证明 严格凸 光滑性 凸性 极光
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K -强凸性的特征 被引量:4
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作者 张子厚 方习年 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第4期100-104,共5页
指出了三种形式的 K-强凸定义实质上是等价的 .证明了 K-强凸性的三个特征 .证明了 K -强光滑性的一个特征以及
关键词 k-强凸 k-强光滑 LkUR空间 对偶映射
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关于smooth群的两个重要结果 被引量:4
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作者 赵建立 马振明 李莹 《山东大学学报(理学版)》 CAS CSCD 北大核心 2005年第6期18-21,共4页
证明了强smooth群与smooth群是等价的,简化了smooth群理论;验证了以模糊相等作为模糊等价关系将smooth群元素分类后所得到的商集在模糊运算诱导的运算下做成群.
关键词 模糊函数 smooth smooth
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K-弱凸性与K-弱光滑性 被引量:6
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作者 黎永锦 舒小保 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第5期8-10,共3页
提出了K_弱凸性与K_弱光滑性 ,作为K_强凸性与K_强光滑性的推广 ,然后证明了K_弱凸性与K_弱光滑性是对偶性质 ;Banach空间X是非常凸的当且仅当X是严格凸的且K_弱凸的 ;Banach空间X是局部一致凸的当且仅当X是K_强凸的和严格凸的且具有 (... 提出了K_弱凸性与K_弱光滑性 ,作为K_强凸性与K_强光滑性的推广 ,然后证明了K_弱凸性与K_弱光滑性是对偶性质 ;Banach空间X是非常凸的当且仅当X是严格凸的且K_弱凸的 ;Banach空间X是局部一致凸的当且仅当X是K_强凸的和严格凸的且具有 (WM)性质。 展开更多
关键词 k-弱凸性 k-弱光滑性 k-弱暴露点 (WM)性质 BANACH空间 对偶性质 局部一致凸
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关于Banach空间的k-光滑性 被引量:4
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作者 魏文展 程庆进 董鸽 《数学杂志》 CSCD 北大核心 2006年第3期292-296,共5页
本文研究了k-光滑的Banach空间,引入了k-G可微性的概念.得到了k-光滑的Banach空间的几个等价条件.
关键词 k-光滑 k-G可微 支撑映射
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k-非常凸、k-非常光滑与(弱)中点局部k-一致光滑空间 被引量:6
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作者 陈利国 罗成 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第5期494-497,共4页
引入推广的Banach空间的k-非常凸、k-非常光滑、(弱)中点局部k-一致光滑性的概念,讨论了它们与其它k-凸性(k-光滑性)之间的关系,证明k-非常凸性和k-非常光滑性具有对偶性质,(弱)中点局部k-一致光滑性与(弱)中点局部k-一致凸性具有对偶性质.
关键词 k-非常凸 k-非常光滑 (弱)中点局部k-一致凸 (弱)中点局部k-一致光滑
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