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基于模糊n-cell数的非线性投入产出模型解的存在性
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作者 陆星宇 叶国菊 刘尉 《湖北大学学报(自然科学版)》 CAS 2024年第2期225-232,共8页
将混合单调以及耦合不动点的概念引入到模糊n-cell数空间中,给出此空间上的混合单调型不动点定理。考虑到模糊n-cell数具有表示n维不确定信息的特点,将非线性投入产出模型与模糊n-cell数相结合,建立模糊非线性投入产出模型并给出相应的... 将混合单调以及耦合不动点的概念引入到模糊n-cell数空间中,给出此空间上的混合单调型不动点定理。考虑到模糊n-cell数具有表示n维不确定信息的特点,将非线性投入产出模型与模糊n-cell数相结合,建立模糊非线性投入产出模型并给出相应的平衡方程。最后利用本文中所给的不动点定理讨论此模型解存在的条件,验证模型的合理性。 展开更多
关键词 模糊n-cell数 混合单调 不动点定理 非线性投入产出模型
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关于N型映射的迭代和终于不动点
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作者 陈凯 石勇国 《纯粹数学与应用数学》 2024年第2期366-380,共15页
函数迭代通常会发生复杂的动力学现象,即使是简单的函数,甚至是逐段的线性函数的迭代都很复杂.通常计算出一个分段线性函数的n次迭代精确表达式非常困难.本文考虑N型映射的动力学性质,定义了一个关于N型映射的指标函数.利用这个指标函数... 函数迭代通常会发生复杂的动力学现象,即使是简单的函数,甚至是逐段的线性函数的迭代都很复杂.通常计算出一个分段线性函数的n次迭代精确表达式非常困难.本文考虑N型映射的动力学性质,定义了一个关于N型映射的指标函数.利用这个指标函数,本文给出了该映射n次迭代精确表达式,同时给出了终于不动点恰好第n步映到不动点的充分必要条件. 展开更多
关键词 n型映射 n阶迭代 终于不动点
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C_(4)F_(7)N/CO_(2)混合气体湿度检测技术研究
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作者 谢成 邵先军 +3 位作者 张伟 王鑫 丁五行 何毅帆 《高压电器》 CAS CSCD 北大核心 2024年第9期148-154,共7页
电气设备中C_(4)F_(7)N/CO_(2)混合绝缘气体的湿度水平影响气体的绝缘性能,定期检测湿度是日常运维工作之一。文中研究采用变电站日常运维中常规的冷镜式露点仪和阻容式湿度计对不同湿度的C_(4)F_(7)N/CO_(2)混合绝缘气体进行检测,实验... 电气设备中C_(4)F_(7)N/CO_(2)混合绝缘气体的湿度水平影响气体的绝缘性能,定期检测湿度是日常运维工作之一。文中研究采用变电站日常运维中常规的冷镜式露点仪和阻容式湿度计对不同湿度的C_(4)F_(7)N/CO_(2)混合绝缘气体进行检测,实验表明上述常规湿度检测仪器均不能直接应用于C_(4)F_(7)N/CO_(2)混合气体的湿度检测。文中将上述冷镜式露点仪进行技术改造后,采用标准湿度的C_(4)F_(7)N/CO_(2)混合气体对其进行准确度实验,结果表明,改造后的冷镜式露点仪的露点测量误差不超过±0.2℃,且在C_(4)F_(7)N比例不超过12%时可准确检测不低于150μL/L的湿度,满足C_(4)F_(7)N/CO_(2)混合气体电气设备的运维要求。上述阻容式湿度计经过C_(4)F_(7)N/CO_(2)混合气体湿度发生器重新标定后也可用于C_(4)F_(7)N/CO_(2)混合气体的湿度检测,露点测量误差不超过±2.0℃。 展开更多
关键词 C_(4)F_(7)n/CO_(2)混合气体 湿度检测 冷镜式露点仪 制冷温度控制
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关于N型映射的周期点计数和Devaney混沌性
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作者 叶瑞松 任甜甜 高曼钰 《徐州工程学院学报(自然科学版)》 CAS 2023年第2期1-7,共7页
探讨了N型映射的周期点的计数问题,提供了周期点的具体计算公式;进一步从实数的三进制表示的角度,阐释了N型映射的Devaney混沌性.
关键词 n型映射 周期点 Devaney混沌性
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“1+1+1+N”专业融合体建设的内涵意蕴、逻辑起点与实践样本
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作者 姜汉荣 《职教通讯》 2023年第9期42-48,共7页
专业建设是中国式职业教育现代化生动实践的重要组成部分。“1+1+1+N”专业融合体以中职学校为核心主体,与职教本科、高职院校以及区域企业等利益主体进行多维、深度合作,因而需从人才培养、科研服务、社会服务、文化传承与创新、国际... 专业建设是中国式职业教育现代化生动实践的重要组成部分。“1+1+1+N”专业融合体以中职学校为核心主体,与职教本科、高职院校以及区域企业等利益主体进行多维、深度合作,因而需从人才培养、科研服务、社会服务、文化传承与创新、国际交流与合作等办学功能上理清“1+1+1+N”专业融合体建设的内涵意蕴,并锚定服务面向、问题导向和系统思维等“1+1+1+N”专业融合体建设的逻辑起点,同时围绕延伸教育链、服务产业链、支撑供应链、打造人才链、提升价值链等几个方面,创新实践“1+1+1+N”专业融合体建设与发展,初步为中国式职业教育现代化提供可能的实践样本。 展开更多
关键词 “1+1+1+n”专业融合体 内涵意蕴 逻辑起点 实践样本
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多点进水AAO-A+MBR工艺在低C/N污水处理厂的工程应用 被引量:4
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作者 沈超 任玉辉 《净水技术》 CAS 2023年第1期168-173,共6页
海宁丁桥污水处理厂四期工程处理规模为5×10^(4)m^(3)/d,进水中工业废水占比高达50%,进水C/N较低。根据现有用地、进水指标及工艺运行情况,新建初沉发酵池+多点进水AAO-A+MBR工艺系统,采用多点进水耦合乙酸钠投加的多碳源分配脱氮... 海宁丁桥污水处理厂四期工程处理规模为5×10^(4)m^(3)/d,进水中工业废水占比高达50%,进水C/N较低。根据现有用地、进水指标及工艺运行情况,新建初沉发酵池+多点进水AAO-A+MBR工艺系统,采用多点进水耦合乙酸钠投加的多碳源分配脱氮保障方法,同时采用了将曝气池溶解氧控制在较低水平的策略。投入运行一年多,在进水COD_(Cr)、氨氮、TP、TN、SS平均质量浓度分别为254.0、29.30、3.09、31.60、126.3 mg/L的情况下,出水COD_(Cr)、氨氮、TP、TN、SS平均质量浓度分别为26.2、0.31、0.23、7.72、5.1 mg/L,出水水质稳定达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)中的一级A标准,单位直接运行成本为0.5330元/m^(3),具有良好的环境效益和经济效益。 展开更多
关键词 污水处理厂 低碳氮比 多点进水 溶解氧 MBR工艺 工程设计
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Controlled-release fertilizer(CRF): A green fertilizer for controlling non-point contamination in agriculture 被引量:20
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作者 MAOXiao-yun SUNKe-jun WANGDe-han LIAOZong-wen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期181-184,共4页
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has... Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture. 展开更多
关键词 controlled-release fertilizer n use efficiency non-point contamination
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Determination of work-hardening exponent for sheet metal using three-point method 被引量:1
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作者 康达昌 田浩彬 刘现平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期275-277,共3页
Three characteristic points in the deformation history of a fractured tensile specimen are selected tocalculate two values of n( n1 and n2 ) to represent the hardening ability of material during the homogeneous plas-t... Three characteristic points in the deformation history of a fractured tensile specimen are selected tocalculate two values of n( n1 and n2 ) to represent the hardening ability of material during the homogeneous plas-tic deformation and the following large plastic deformation. Experimental results obtained with mild streel andred copper show that n determined using the three-point method proposed is better to describe the hardening a-bility of material. It is therefore concluded that three-point method can be used to describe the hardening prop-erty of material during both homogeneous deformation and large plastic deformation. 展开更多
关键词 work-hardening exponent (n) Three-point method characteristic points tensile test
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RNA m^(6)A甲基化修饰在皮肤黑色素瘤免疫调控机制中的研究进展
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作者 姜晓铮 王烨涛 王焱 《医学综述》 CAS 2023年第5期890-896,共7页
皮肤黑色素瘤免疫原性高,对传统治疗抵抗,免疫治疗是皮肤黑色素瘤治疗方案中的新兴手段,而疗效的差异性是亟待解决的问题,引发了对皮肤黑色素瘤免疫调控机制的探索。RNA N 6-甲基腺苷(m^(6)A)甲基化修饰在皮肤黑色素瘤的发生、发展、转... 皮肤黑色素瘤免疫原性高,对传统治疗抵抗,免疫治疗是皮肤黑色素瘤治疗方案中的新兴手段,而疗效的差异性是亟待解决的问题,引发了对皮肤黑色素瘤免疫调控机制的探索。RNA N 6-甲基腺苷(m^(6)A)甲基化修饰在皮肤黑色素瘤的发生、发展、转移中发挥了重要作用。目前皮肤黑色素瘤主要通过肿瘤微环境、免疫检查点分子及其下游通路进行免疫调控,而m^(6)A调节因子参与其中。探索RNA m^(6)A甲基化修饰与皮肤黑色素瘤免疫调控机制的关系将有助于皮肤黑色素瘤免疫治疗的精准靶向,提高免疫治疗效果。 展开更多
关键词 皮肤黑色素瘤 n^(6)-甲基腺苷调节因子 免疫治疗 肿瘤微环境 免疫检查点
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m-degree Center-connecting Line of Finite Points Set and Its Properties 被引量:1
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作者 ZHOU Yong-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期247-252,共6页
In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formu... In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formula in finite points set. As its application,we extend the Leibniz formula and length of medians formula in n-dimensional simplex to polytope. 展开更多
关键词 n-dimensional Euclidean space finite points set m-degree center-connectingline PROPERTIES
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A New Thioamide Derivative for Separation and Preconcentration of Multi Elements in Aquatic Environment by Cloud Point Extraction 被引量:1
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作者 Mohamed M. Hassanien Ali M. Hassan +1 位作者 Wael I. Mortada Ahmed A. El-Asmy 《American Journal of Analytical Chemistry》 2011年第6期697-709,共13页
2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in wat... 2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results. 展开更多
关键词 HEAVY Metals PRECOnCEnTRATIOn Cloud point Extraction 2-(Pyridine-2-Yl)-n-P-Chlorohydrazinecarbothioamide
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关于n重积分对称性的一点思考
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作者 刘丽君 《高等数学研究》 2023年第2期61-63,共3页
本文从多维度的视角通过定义n维空间两个点的对称以及两个集合(区域)的对称,把奇偶函数在对称区间求定积分的性质推广到了n维空间求n重积分,对定积分、重积分对称性计算公式在形式上进行了统一.利于n重积分的简便、快捷、正确计算.
关键词 n维空间 n重积分 对称点 对称区域 对称性
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Nonlinear Properties of an Inhomogeneous Diode Structure in a Strong Microwave Field
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作者 Sanobar Reymbaeva Gulmurza Abdurakhmanov Aleksandra Orel 《World Journal of Condensed Matter Physics》 CAS 2023年第1期1-13,共13页
Results of experimental investigation of detection (rectification) of high power X-band microwave signal in diodes of various design (semiconductor p-n-junction, point-contact, Schottky, Metal-Isolator-Metal—MIM) are... Results of experimental investigation of detection (rectification) of high power X-band microwave signal in diodes of various design (semiconductor p-n-junction, point-contact, Schottky, Metal-Isolator-Metal—MIM) are reported. The maximum of the detected direct voltage V vs. power P of microwave signal and subsequent polarity reversal, previously found in MIM diodes in the optical and microwave bands, have found to be characteristic of all investigated diodes as well. After the reversal of polarity, this dependence comes linear, and the sign of the voltage corresponds to thermoEMF. In some diodes, the hysteresis on V(P) was observed. All 5 types of V(P) of MIM diodes (have made from different pairs of metals), reported earlier, were reproduced on same p-n-junction diode by variable external DC bias. These results joined with abnormal frequency cutoff forced to suggest that there is an unknown mechanism for direct flow of charge carriers (and for generate direct current) in the high-frequency electrical field, which differs from the conventional rectification. 展开更多
关键词 Quadratic Detection p-n-Junction point Contact Schottky Barrier High-Power Microwave Signal Polarity Reversal ThermoEMF HYSTERESIS
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Point Correspondences between <i>N</i>+ 1 Hypersurfaces of Projective Spaces and (<i>N</i>+ 1)-Webs
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作者 V. S. Bolodurin 《Applied Mathematics》 2013年第11期14-22,共9页
For a correspondence in question we establish a sequence of fundamental geometrical objects of the correspondence and find invariant normalizations of the first and second orders of all hupersurfaces under the corresp... For a correspondence in question we establish a sequence of fundamental geometrical objects of the correspondence and find invariant normalizations of the first and second orders of all hupersurfaces under the correspondence. We single out main tensors of the correspondence and establish a connection between the geometry of point correspondences between n + 1 hypersurfaces of projective spaces and the theory of multidimensional (n + 1)-webs. 展开更多
关键词 Hupersurface point CORRESPOnDEnCE Invariant normalization Multidimensional (n + 1)-Webs
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L_p(1≤p≤∞) APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A SET OF n+1 POINTS
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作者 史应光 《Acta Mathematica Scientia》 SCIE CSCD 1993年第4期430-436,共7页
Some new characterizations and immediate explicit expressions of best L(1≤p≤∞) approximation and their deviations by an n-dimensional subspace on a set of n+1 points are given.
关键词 APPROXIMATIOn BY An n-DIMEnSIOnAL SUBSPACE On A SET OF n+1 pointS L_p ID Case
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ON THE EXISTENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n=Q to (F(x,u,Du))+integral from n=■Q to (G(x,u))
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作者 严树森 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期231-240,共10页
In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o... In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o to u (g(x,t)dt), under the weak structure conditions on F(x, u, q) by the Mountain Pass Lemma. 展开更多
关键词 On THE EXISTEnCE OF InFInITELY MAnY CRITICAL pointS OF THE EVEn FUnCTIOnAL integral from n=Q to x u Du On THE EXISTEnCE OF InFInITELY MAnY CRITICAL pointS OF THE EVEn FUnCTIOnAL integral from n Q to x u
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Singularities of the Moduli Space of n Unordered Points on the Riemann Sphere
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作者 WU Yue XU Bin 《Chinese Quarterly Journal of Mathematics》 2020年第2期145-162,共18页
We classify the nite groups associated to the orbifold singularities of the moduli space of n≥5 unordered points on the Riemann sphere.
关键词 STABILIZER Orbifold singularity Unordered n point Riemann sphere
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Transmission System Reconfiguration to Reduce Losses and Cost Ensuring Voltage Security
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作者 Veerapandiyan V. Mary D. 《Journal of Power and Energy Engineering》 2016年第6期4-12,共9页
The aim of this paper is to reduce the losses, total generation cost by switching of transmission line and to maintain voltage security under N - 1 contingency conditions. Generation cost is calculated and the pr... The aim of this paper is to reduce the losses, total generation cost by switching of transmission line and to maintain voltage security under N - 1 contingency conditions. Generation cost is calculated and the priority list is made for switching the line. The problem is solved by ACOPF using Interior Point Method. In order to test the feasibility and effectiveness of the above method, a sample 6-bus system and IEEE 30-bus system have been used. The impact of switching on system parameter includes the generation cost, locational marginal pricing (LMP) and transmission losses, ensuring voltage security of the system. 展开更多
关键词 Transmission Switching (TS) AC Optimal Power Flow (ACOPF) n - 1 Contingency and Interior point Method
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Study of Fixed Point Theorems for Higher Dimension in Partially Ordered Metric Spaces
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作者 Ibtisam Masmali Sumitra Dalal 《Applied Mathematics》 2016年第5期399-412,共14页
In this paper, we establish the existence and uniqueness of fixed points of operator , when n is an arbitrary positive integer and X is a partially ordered complete metric space. We have shown examples to verify our w... In this paper, we establish the existence and uniqueness of fixed points of operator , when n is an arbitrary positive integer and X is a partially ordered complete metric space. We have shown examples to verify our work. Our results generalize the recent fixed point theorems cited in [1]-[4] etc. and include several recent developments. 展开更多
关键词 n-Tupled Coincidence points n-Tupled Coincidence Fixed points Compatible Maps Fixed points and Partially Ordered Metric Spaces
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<i>N</i>-Order Fixed Point Theory for N-Order Generalized Meir-Keeler Type Contraction in Partially Ordered Metric Spaces
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作者 Shiyun Wang Jingwen Zhang 《Journal of Applied Mathematics and Physics》 2019年第5期1174-1184,共11页
This paper concerns N-order fixed point theory in partially ordered metric spaces. For the sake of simplicity, we start our investigations with the tripled case. We define tripled generalized Meir-Keeler type contract... This paper concerns N-order fixed point theory in partially ordered metric spaces. For the sake of simplicity, we start our investigations with the tripled case. We define tripled generalized Meir-Keeler type contraction which extends the definition of [Bessem Samet, Coupled fixed point theorems for a generalized Meir-Keeler contraction in partially ordered metric spaces, Nonlinear Anal. 72 (2010), 4508-4517]. We then discuss the existence and uniqueness of tripled fixed point theorems in partially ordered metric spaces. For general cases, we generalized our results to the N-order case. The results will promote the study of N-order fixed point theory. 展开更多
关键词 Tripled Fixed point Meir-Keeler TYPE COnTRACTIOn PARTIALLY Ordered Set n-Order Fixed point
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