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基于加权Ripley's K-function的多尺度景观格局分析——以江苏盐城滨海湿地为例 被引量:13
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作者 张东菊 左平 邹欣庆 《生态学报》 CAS CSCD 北大核心 2015年第8期2703-2711,共9页
以1987,1992,1997,2002,2007年的遥感影像为例,首次尝试使用加权Ripley's K-function的多尺度格局分析方法,计算了20年来景观异质性在江苏盐城滨海湿地的时间变化和空间分布趋势。通过对研究区的样带划分以及景观类型的点状化处理,... 以1987,1992,1997,2002,2007年的遥感影像为例,首次尝试使用加权Ripley's K-function的多尺度格局分析方法,计算了20年来景观异质性在江苏盐城滨海湿地的时间变化和空间分布趋势。通过对研究区的样带划分以及景观类型的点状化处理,建立滨海湿地样带图层和1987—2007年间各类型景观的点格局数据库,从而分析滨海湿地不同类型景观的空间聚集特征变化。基于加权Ripley's K-function的计算表明,在各级空间尺度和时间变化上,各类型湿地的斑块都呈现出空间聚集分布状态,且1987年以来,不同湿地类型的聚集空间特征尺度和空间分布强度均出现了大幅的增减变化,除互花米草滩之外的自然湿地的聚集空间特征尺度和强度都有明显下降甚至少到无法被检测到,而人工湿地却呈现聚集特征尺度和强度的双增长,且该聚集程度有逐渐增强的趋势。分析表明,既考虑样点的空间位置信息又考虑样点分布范围的加权Ripley's K-function方法能很好地表征湿地景观在多尺度上的变异,且与传统空间景观指数等分析方法的结论在一定程度上保持一致。 展开更多
关键词 盐城滨海湿地 景观空间格局 多尺度空间聚集分析 加权Ripley’s k-function 空间特征尺度 空间分布强度
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K-凸复合函数的性质
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作者 万莉娟 崔继贤 李晓丹 《高师理科学刊》 2025年第7期8-11,共4页
借助K-凸函数的K-回收映射和K-雅可比映射得到了K-凸复合函数的几个性质。
关键词 k-凸函数 k-回收映射 k-雅可比映射 k-凸复合函数
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A Laurent Expansion and Residue Theorems of k-Regular Functions in Clifford Analysis 被引量:2
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作者 KU Min DU Jinyuan 《Wuhan University Journal of Natural Sciences》 CAS 2009年第2期97-102,共6页
In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness... In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness, give the definitions of k-poles, isolated and essential singular points and removable singularity, discuss some properties, and further obtain the residue theorems. 展开更多
关键词 Clifford algebra k-regular functions Laurent expansion residue theorems SINGULARITY
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The Non-standard Characteristics of Functional SpacesK(X) and C_0(X) 被引量:1
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作者 陈东立 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期7-9, ,共3页
In this paper,the non standard characteristics of functional spaces K(X) and C 0(X) are presented and proved.
关键词 functional space k(X) functional space C 0(X) near standard points remote points
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Certain Integral Transforms of Generalized k-Bessel Function
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作者 Kottakkaran Sooppy Nisar Waseem Ahmad Khan Mohd Ghayasuddin 《Analysis in Theory and Applications》 CSCD 2018年第2期165-174,共10页
The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We ... The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We have also discussed some other transforms as special cases of our main results. 展开更多
关键词 GAMMA function k-Bessel function generalized k-Bessel function INTEGRAL transforms
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A SPECIAL MODULUS OF CONTINUITY AND THE K-FUNCTIONAL
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作者 Nadezhda DOLMATOVA 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1531-1540,共10页
We consider the questions connected with the approximation of a real continuous 1-periodic functions and give a new proof of the equivalence of the special Boman-Shapiro modulus of continuity with Peetre’s K-function... We consider the questions connected with the approximation of a real continuous 1-periodic functions and give a new proof of the equivalence of the special Boman-Shapiro modulus of continuity with Peetre’s K-functional. We also prove Jackson’s inequality for the approximation by trigonometric polynomials. 展开更多
关键词 modulus of continuity k-functionAL Jackson's theorem
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THE NONLINEAR BOUNDARY VALUE PROBLEM FOR k HOLOMORPHIC FUNCTIONS IN C^(2)
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作者 崔艳艳 李尊凤 +1 位作者 谢永红 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1571-1586,共16页
k holomorphic functions are a type of generation of holomorphic functions.In this paper,a nonlinear boundary value problem for k holomorphic functions is primarily discussed on generalized polycylinders in C^(2).The e... k holomorphic functions are a type of generation of holomorphic functions.In this paper,a nonlinear boundary value problem for k holomorphic functions is primarily discussed on generalized polycylinders in C^(2).The existence of the solution for the problem is studied in detail with the help of the boundary properties of Cauchy type singular integral operators with a k holomorphic kernel.Furthermore,the integral representation for the solution is obtained. 展开更多
关键词 k holomorphic functions boundary value problems Cauchy type singular integral operators
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维生素K的功能、吸收与代谢研究进展 被引量:2
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作者 王海燕 聂淑慧 +1 位作者 胡贻椿 杨晓光 《营养学报》 北大核心 2025年第1期92-98,共7页
近年来,维生素K除了凝血功能之外,还表现出防治骨质疏松、改善心血管疾病、预防糖尿病及特定癌症等多方面的潜在健康效应。本文从生理功能以及转运转化、吸收利用、储存排泄等方面入手,阐述了维生素K_(1)和维生素K_(2)的异同,并综述了... 近年来,维生素K除了凝血功能之外,还表现出防治骨质疏松、改善心血管疾病、预防糖尿病及特定癌症等多方面的潜在健康效应。本文从生理功能以及转运转化、吸收利用、储存排泄等方面入手,阐述了维生素K_(1)和维生素K_(2)的异同,并综述了维生素K的形式、膳食组成及基因多态性(APOE,VKOR,CYP4F2等)对维生素K代谢的影响,为后续维生素K与相关疾病的研究及膳食参考摄入量的制订提供参考。 展开更多
关键词 维生素k 生理功能 吸收 代谢
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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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Convexity for New Integral Operator on k-uniformly p-valent a-convex Functions of Complex Order 被引量:1
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作者 LI Shu-hai MA Li-na A O-en 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期88-96,共9页
In this paper, we obtain the convexity of new general integral operator on some classes of k-uniformly p-valent a-convex functions of complex order. These results extend some known theorems.
关键词 analytic functions p-valently k-uniformly STARLIkE CONVEX integral operator
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Construction of <i>k</i>-Variate Survival Functions with Emphasis on the Case <i>k</i>= 3
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作者 Jerzy K. Filus Lidia Z. Filus 《Applied Mathematics》 2020年第7期678-697,共20页
The purpose of this paper is to present a general universal formula for <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;&... The purpose of this paper is to present a general universal formula for <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;">-variate survival functions for arbitrary <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 2, 3, <span style="font-family:;" "=""><span style="font-family:Verdana;">...<span style="font-family:Verdana;">, given all the univariate marginal survival functions. This universal form of <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;">-variate probability distributions was obtained by means of “dependence functions” named “joiners” in the text. These joiners determine all the involved stochastic dependencies between the underlying random variables. However, in order that the presented formula (the form) represents a legitimate survival function, some necessary and sufficient conditions for the joiners had to be found. Basically, finding those conditions is the main task of this paper. This task was successfully performed for the case <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 2 and the main results for the case <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 3 were formulated as Theorem 1 and Theorem 2 in Section 4. Nevertheless, the hypothetical conditions valid for the general <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> ≥ 4 case were also formulated in Section 3 as the (very convincing) Hypothesis. As for the sufficient conditions for both the <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:;" "=""><span style="font-family:Verdana;"> = 3 and <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> ≥ 4 cases, the full generality was not achieved since two restrictions were imposed. Firstly, we limited ourselves to the, defined in the text, “continuous cases” (when the corresponding joint density exists and is continuous), and secondly we consider positive stochastic dependencies only. Nevertheless, the class of the <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;">-variate distributions which can be constructed is very wide. The presented method of construction by means of joiners can be considered competitive to the <span style="font-family:Verdana;"><span style="font-family:Verdana;">copula<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> methodology. As it is suggested in the paper the possibility of building a common theory of both copulae and joiners is quite possible, and the joiners may play the role of tools within the theory of copulae, and vice versa copulae may, for example, be used for finding proper joiners. Another independent feature of the joiners methodology is the possibility of constructing many new stochastic processes including stationary and Markovian. 展开更多
关键词 Construction of Multivariate Probability Distributions via Joiners Joiner versus Copula Methodology A Possible Fusion of the Two Construction Methods k -Variate Survival function Scheme k = 3 Case
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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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AVERAGE σ-K WIDTH OF CONVOLUTION FUNCTION CLASS OF L_(pq) (R) IN L_q(R)
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作者 Liu Yongping Beijing Normal University. Beijing 《Analysis in Theory and Applications》 1994年第1期34-46,共13页
In this paper. we study the average n-K width of the convolution class B_(pq)(G)(or B_(?)(G)), for which the kernel G(x) is a PF density, in the metric L_q(R)(or L_(qp)(R)) for the case 1≤q<p ≤∞, and obtain some... In this paper. we study the average n-K width of the convolution class B_(pq)(G)(or B_(?)(G)), for which the kernel G(x) is a PF density, in the metric L_q(R)(or L_(qp)(R)) for the case 1≤q<p ≤∞, and obtain some exact results. 展开更多
关键词 IN L_q k WIDTH OF CONVOLUTION function CLASS OF L PQ AVERAGE Math
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一类C-K型方程组Cauchy问题的可解性
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作者 金启胜 《安阳师范学院学报》 2025年第5期6-9,共4页
为了研究一类C-K型方程组Cauchy问题的解析解,首先把高阶非线性C-K型方程组的Cauchy问题简化成一个与它等价的一阶拟线性C-K型方程组的Cauchy问题,然后利用归纳法和强函数方法证明了该Cauchy问题在某个邻域内存在唯一的解析解。
关键词 C-k型方程组 CAUCHY问题 强函数 解析解
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K-Dimension and Hlder Exponent for Bush Type Fractal Functions
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作者 王宏勇 《Journal of Southwest Jiaotong University(English Edition)》 2006年第4期400-403,共4页
Bush type fractal functions were defined by means of the expression of Cantor series of real numbers. The upper and lower bound estimates for the K-dimension of such functions were given. In a typical case, the fracta... Bush type fractal functions were defined by means of the expression of Cantor series of real numbers. The upper and lower bound estimates for the K-dimension of such functions were given. In a typical case, the fractal dimensional relations in which the K-dimension equals the box dimension and packing dimension were presented; moreover, the exact Holder exponent were obtained for such Bush type functions. 展开更多
关键词 Bush type function Fractal function k-DIMENSION Holder exponent
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On Functions of K-Balanced Matroids
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作者 Talal Al-Hawary 《Open Journal of Discrete Mathematics》 2017年第3期103-107,共5页
In this paper, we prove an analogous to a result of Erd&ouml;s and Rényi and of Kelly and Oxley. We also show that there are several properties of k-balanced matroids for which there exists a threshold function.
关键词 k-Balanced MATROID PROJECTIVE Geometry THRESHOLD function
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Wear State Recognition of Drills Based on K-means Cluster and Radial Basis Function Neural Network 被引量:2
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作者 Xu Yang 《International Journal of Automation and computing》 EI 2010年第3期271-276,共6页
Drill wear not only affects the surface smoothness of the hole, but also influences the life of the drill. Drill wear state recognition is important in the manufacturing process, which consists of two steps: first, d... Drill wear not only affects the surface smoothness of the hole, but also influences the life of the drill. Drill wear state recognition is important in the manufacturing process, which consists of two steps: first, decomposing cutting torque components from the original signals by wavelet packet decomposition (WPD); second, extracting wavelet coefficients of different wear states (i.e., slight, normal, or severe wear) with signal features adapting to Welch spectrum. Finally, monitoring and recognition of the feature vectors of cutting torque signal are performed by using the K-means cluster and radial basis function neural network (RBFNN). The experiments on different tool wears of the multivariable features reveal that the results of monitoring and recognition are significant and effective. 展开更多
关键词 Drill wear state recognition cutting torque signals wavelet packet decomposition (WPD) Welch spectrum energy k-means cluster radial basis function neural network
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人参皂苷CK对重症急性胰腺炎大鼠胰腺组织和血清炎性细胞因子的影响
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作者 郭盛滕 商琼琼 +1 位作者 曲桂武 王庆华 《滨州医学院学报》 2025年第1期12-15,共4页
目的探讨人参皂苷CK对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠胰腺组织和血清炎性细胞因子的影响。方法选取健康雄性清洁级SD大鼠50只,随机分为假手术对照组(SO组),SAP组和人参皂苷CK低、中、高三个剂量组(人参皂苷CK混悬... 目的探讨人参皂苷CK对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠胰腺组织和血清炎性细胞因子的影响。方法选取健康雄性清洁级SD大鼠50只,随机分为假手术对照组(SO组),SAP组和人参皂苷CK低、中、高三个剂量组(人参皂苷CK混悬液浓度分别为1.0、2.0、4.0 mg·mL^(-1)),每组10只。除SO组外,其余各组大鼠均采用逆行胰胆管注射3.8%牛磺胆酸钠制备SAP模型,干湿法检测大鼠胰腺组织水肿指数变化;采集大鼠腹主动脉血检测血清淀粉酶(AMY)和脂肪酶(LPS)水平;采用酶联免疫吸附剂测定法(ELISA)检测大鼠血清肿瘤坏死因子(TNF-α)、白介素-1β(IL-1β)及白介素-6(IL-6)水平。结果与SO组比较,SAP组大鼠胰腺组织水肿指数、血清淀粉酶、脂肪酶、TNF-α、IL-1β和IL-6水平增高(P<0.05)。与SAP组比较,人参皂苷CK不同剂量组大鼠胰腺组织水肿指数、血清淀粉酶、脂肪酶、TNF-α、IL-1β及IL-6水平均降低(P<0.01)。结论人参皂苷CK具有抗炎活性,作为辅助治疗SAP的有效手段,具有胰腺组织保护作用和减轻SAP大鼠炎症反应的作用。 展开更多
关键词 人参皂苷Ck 重症急性胰腺炎 胰腺功能 炎性细胞因子
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京津冀地区城市韧性时空演化研究:基于功能共振与改进K-shell的贝叶斯网络方法
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作者 徐晋成 孙思睿 石常峰 《环境生态学》 2025年第11期69-78,共10页
随着全球经济不确定性与气候变化风险叠加,京津冀地区发展失衡与生态约束趋紧等系统性挑战日益凸显,科学评估城市韧性已成为促进京津冀可持续发展的关键抓手。基于复杂适应系统理论,创新性地整合功能共振分析方法(FRAM)、改进的K-shell(... 随着全球经济不确定性与气候变化风险叠加,京津冀地区发展失衡与生态约束趋紧等系统性挑战日益凸显,科学评估城市韧性已成为促进京津冀可持续发展的关键抓手。基于复杂适应系统理论,创新性地整合功能共振分析方法(FRAM)、改进的K-shell(MKS)分解算法和贝叶斯网络(BN),构建了涵盖经济、社会、环境、基础设施多维度的评价体系,对京津冀13个城市2013—2022年的城市韧性进行定量评估与时空演化分析。研究结果表明:1)2013—2022年,京津冀城市韧性总体呈上升趋势,但区域内部分化显著,北京、天津双核结构固化,其韧性水平远超河北省各市;2)疫情冲击下,韧性表现因经济结构和政策响应而异;3)通过改进的K-shell分解算法和贝叶斯网络模型研究发现,政府财政能力(F_(5))是影响城市韧性的最为关键的因素,韧性提升需经济、社会、环境、基础设施多维度协同推进。基于此,提出政策建议:1)强化区域协同与顶层设计,优化资源配置,推动北京、天津优质资源向河北疏解赋能,缩小韧性差距;2)优化区域产业结构,培育多元化现代产业体系,建立健全产业链风险防范机制;3)聚焦政府财政、社会保障、居民增收等核心要素,坚持系统思维,构筑韧性综合支撑体系。 展开更多
关键词 城市韧性评价 京津冀地区 功能共振分析 k-shell算法 贝叶斯网络
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Different Solid-state Fermentation technology of Functional Red yeast rice has an effect on the morphological change of MonacolinK
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作者 Lei Lu Yao Li Xiuhe Liu 《科技信息》 2014年第12期62-63,67,共3页
Different technical conditions in the process of solid-state fermentation of red yeast rice has a certain impact on the production of acid-form and lactone form Monacolin K.When cultured in the loose rice medium,the a... Different technical conditions in the process of solid-state fermentation of red yeast rice has a certain impact on the production of acid-form and lactone form Monacolin K.When cultured in the loose rice medium,the acid form Monacolin K accounts for 50%-60%;while the acid form Monacolin K accounts for 80%-90%cultured in the consolidated rice medium.And we also found that the proportion of the acid form and lactone form Monacolin K will decrease with the increase of fermentation time. 展开更多
关键词 functionAL RED YEAST rice Monacolin k the acid for
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