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Construction of Split-Plot Designs with General Minimum Lower Order Confounding
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作者 Kexin Li Beichen Han Zhenzhen Niu 《Open Journal of Applied Sciences》 CAS 2023年第3期261-274,共14页
Fractional factorial split-plot design has been widely used in many fields due to its advantage of saving experimental cost. The general minimum lower order confounding criterion is usually used as one of the attracti... Fractional factorial split-plot design has been widely used in many fields due to its advantage of saving experimental cost. The general minimum lower order confounding criterion is usually used as one of the attractive design criterion for selecting fractional factorial split-plot design. In this paper, we are interested in the theoretical construction methods of the optimal fractional factorial split-plot designs under the general minimum lower order confounding criterion. We present the theoretical construction methods of optimal fractional factorial split-plot designs under general minimum lower order confounding criterion under several conditions. 展开更多
关键词 Fractional Factorial Design General Minimum lower order Confounding Criterion Split-Plot Design
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The Lower Orders of Dirichlet and Random Dirichlet Series 被引量:7
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作者 Yu Jiarong (Department of Mathematics,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期1-8,共8页
The formulas of the lower orders of Dirichlet series are given by means of the exponents and the convex regularized sequences of the logarithms and the convex regularized sequences of the logarithms of the moduli of t... The formulas of the lower orders of Dirichlet series are given by means of the exponents and the convex regularized sequences of the logarithms and the convex regularized sequences of the logarithms of the moduli of the coefficients. Corresponding results are obtained for some random Dirichlet series. 展开更多
关键词 Dirichlet series random Dirichlet series lower order convex regularization
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THE LOWER ORDER AND LINEAR ORDER OF MULTIPLE DIRICHLET SERIES 被引量:4
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作者 梁美丽 霍颖莹 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期131-138,共8页
The article investigates the growth of multiple Dirichlet series.The lower order and the linear order of n-tuple Dirichlet series in Cn are defined and some relations between them and the coefficients and exponents of... The article investigates the growth of multiple Dirichlet series.The lower order and the linear order of n-tuple Dirichlet series in Cn are defined and some relations between them and the coefficients and exponents of n-tuple Dirichlet series are obtained. 展开更多
关键词 multiple Dirichlet series lower order linear order
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Orderly coexistence and accumulation models of conventional and unconventional hydrocarbons in Lower Permian Fengcheng Formation,Mahu sag,Junggar Basin 被引量:6
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作者 ZHI Dongming TANG Yong +3 位作者 HE Wenjun GUO Xuguang ZHENG Menglin HUANG Liliang 《Petroleum Exploration and Development》 CSCD 2021年第1期43-59,共17页
By using the latest geological,seismic,drilling and logging data,this article studies the basic conditions for the formation of the total petroleum system and the orderly coexisting characteristics and accumulation mo... By using the latest geological,seismic,drilling and logging data,this article studies the basic conditions for the formation of the total petroleum system and the orderly coexisting characteristics and accumulation models of conventional&unconventional reservoirs in the Lower Permian Fengcheng Formation in the Junggar Basin.Controlled by thermal evolution,hydrocarbon generation and expulsion process of the high-quality source rocks in alkaline lake as well as the characteristics of multi-type reservoirs(conglomerate,sandstone,dolomite and shale),conventional structure-lithologic reservoirs and tight oil and shale oil reservoirs controlled by source-reservoir structure have been formed.On the plane,mature conventional reservoirs,medium-high mature tight oil,and medium-high mature shale oil reservoirs coexist orderly from the slope area around Mahu sag to the sag.Based on the orderly coexisting characteristics of conventional and unconventional reservoirs in the Fengcheng Formation,it is clear that oil and gas in the Fengcheng Formation accumulate continuously over a large area in three accumulation models:integrated source-reservoir,source-reservoir in close contact,and separated source-reservoir model.The three accumulation models differ in relationship between source-reservoir structure,reservoir lithology and spatial distribution,hydrocarbon migration,oil and gas type.It is pointed out that the conventional&unconventional oil and gas should be explored and developed as a whole to achieve an overall breakthrough of the total petroleum system.This study is expected to enrich the geological theory of oil and gas enrichment in continental basins and to provide an analogy for exploration and research in other hydrocarbon-rich sags. 展开更多
关键词 Junggar Basin lower Permian Fengcheng Formation unconventional hydrocarbons orderly coexistence accumulation models shale oil total petroleum system
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Theoretical Explanation for Lower Order Harmonic Resonance Phenomenon of Three-Ring Gear Transmissions 被引量:2
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作者 杨建明 张策 +1 位作者 林忠钦 陈关龙 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第1期71-74,共4页
Dynamic investigations revealed that lower order harmonic resonance phenomenon exists in the three ring gear transmission. That is, when the input speed is close to 1/3, 1/6, 1/9,…, 1/3 n of the primary natural frequ... Dynamic investigations revealed that lower order harmonic resonance phenomenon exists in the three ring gear transmission. That is, when the input speed is close to 1/3, 1/6, 1/9,…, 1/3 n of the primary natural frequency of the transmission, the loads on the bearings and gears are especially high. This paper explained this phenomenon from the viewpoint of parametric resonance in terms of perturbation technique. A conclusion was drawn that the basic reason for this phenomenon is the primary resonance caused by forcing excitation and parametric resonance caused by parametric change. 展开更多
关键词 three ring gear transmission lower order resonance phenomenon natural frequency primary resonance parametric resonance
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Lower Approximation Reduction in Ordered Information System with Fuzzy Decision 被引量:1
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作者 Xiaoyan Zhang Weihua Xu 《Applied Mathematics》 2011年第7期918-921,共4页
Attribute reduction is one of the most important problems in rough set theory. This paper introduces the concept of lower approximation reduction in ordered information systems with fuzzy decision. Moreover, the judgm... Attribute reduction is one of the most important problems in rough set theory. This paper introduces the concept of lower approximation reduction in ordered information systems with fuzzy decision. Moreover, the judgment theorem and discernable matrix are obtained, in which case an approach to attribute reduction in ordered information system with fuzzy decision is constructed. As an application of lower approximation reduction, some examples are applied to examine the validity of works obtained in our works.. 展开更多
关键词 Fuzzy DECISION lower APPROXIMATION REDUCTION orderED Information Systems ROUGH Set
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THE GENERALIZED LOWER ORDER OF DIRICHLET SERIES 被引量:1
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作者 Qingyuan CHEN Yingying HUO 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期1141-1151,共11页
In this paper,we study the generalized lower order of entire functions defined by Dirichlet series.By constructing the Newton polygon based on Knopp-Kojima’s formula,we obtain a relation between the coefficients of t... In this paper,we study the generalized lower order of entire functions defined by Dirichlet series.By constructing the Newton polygon based on Knopp-Kojima’s formula,we obtain a relation between the coefficients of the Dirichlet series and its generalized lower order. 展开更多
关键词 Dirichlet series Knopp-Kojima method Newton polygon generalized lower order
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DOA Estimation Based on Sparse Representation of the Fractional Lower Order Statistics in Impulsive Noise 被引量:8
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作者 Sen Li Rongxi He +1 位作者 Bin Lin Fei Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第4期860-868,共9页
This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive ... This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive noise as α-stable distribution, new methods which combine the sparse signal representation technique and fractional lower order statistics theory are proposed. In the new algorithms, the fractional lower order statistics vectors of the array output signal are sparsely represented on an overcomplete basis and the DOAs can be effectively estimated by searching the sparsest coefficients. To enhance the robustness performance of the proposed algorithms,the improved algorithms are advanced by eliminating the fractional lower order statistics of the noise from the fractional lower order statistics vector of the array output through a linear transformation. Simulation results have shown the effectiveness of the proposed methods for a wide range of highly impulsive environments. 展开更多
关键词 α-stable distribution direction of arrival(DOA) fractional lower-order statistics impulsive noise sparse representation
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The Lower Order and Type of Solutions of Second Order Differential Equation
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作者 ZHANG Shao-hua WU Zhao-jun SUN Dao-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期14-21,共8页
The main purpose of this paper is to study the lower order and type of second order differential equation w"(z)-A(z)w=0,where A(z)is a polynomial.In the case of A(z)=a_dz^d,the authors prove that the lower order ... The main purpose of this paper is to study the lower order and type of second order differential equation w"(z)-A(z)w=0,where A(z)is a polynomial.In the case of A(z)=a_dz^d,the authors prove that the lower order and the type of all non-trivial solutions w of w"(z)-A(z)w=0 are equal to(d+2)/2 and(2(|a_d|)^(1/2))/(d+2)respectively.In the case of A(z)=a_dz^d+a_(d-1)z^(d-1)+…a_1z+a_0,a_d>0,a_(d-1)>0,…,a_1≥0,a_0≥0,the authors prove that the lower order of all non-trivial solutions w of w"(z)-A(z)w=0 is(d+2)/2. 展开更多
关键词 TYPE order lower order differential equation
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New blind estimation method of evoked potentials based on minimum dispersion criterion and fractional lower order statistics
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作者 Daifeng Zha 《Journal of Biomedical Science and Engineering》 2008年第2期91-97,共7页
Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. A... Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. Alpha stable distribution, a generalization of Gaussian, is better for modeling impulsive noises than Gaussian distribution in biomedical signal proc-essing. Conventional blind separation and es-timation method of evoked potentials is based on second order statistics or high order Statis-tics. Conventional blind separation and estima-tion method of evoked potentials is based on second order statistics (SOS). In this paper, we propose a new algorithm based on minimum dispersion criterion and fractional lower order statistics. The simulation experiments show that the proposed new algorithm is more robust than the conventional algorithm. 展开更多
关键词 EVOKED POTENTIALS (EPs) Alpha stable distribution BLIND source separation Minimum dispersion (MD) FRACTIONAL lower order statistics (FLOS)
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医院和科室上下联动事前-事中-事后闭环服务抗菌药物管理模式构建与实践
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作者 杨全军 罗莉 +8 位作者 朱文君 干润 屠祎惺 辛博 杨黎 陈燕 张剑萍 郭澄 刘义成 《中国药业》 CAS 2024年第11期13-16,共4页
目的 促进抗菌药物的合理应用。方法 基于循证证据建立医院和科室上下联动事前-事中-事后闭环服务的抗菌药物管理模式。分析闭环服务的关键节点和服务内容,落实网络化服务体系,完善特殊患者和限制级抗菌药物专项服务等闭环服务的网络干... 目的 促进抗菌药物的合理应用。方法 基于循证证据建立医院和科室上下联动事前-事中-事后闭环服务的抗菌药物管理模式。分析闭环服务的关键节点和服务内容,落实网络化服务体系,完善特殊患者和限制级抗菌药物专项服务等闭环服务的网络干预系统,并比较实施前(2020年)和实施后(2021年至2023年)医院抗菌药物使用强度(AUD)及不合理医嘱类型。结果 2021年、2022年、2023年医院AUD分别为39.40 DDDs、32.10 DDDs、38.09 DDDs,均较2020年的57.80 DDDs低,且符合我国综合医院AUD的限定标准(40 DDDs)。2021年,抗菌药物不合理医嘱类型排名前3的分别为抗菌药物预防/治疗方案不合理、药物选择不合理、联合用药不合理;2022年,抗菌药物不合理医嘱类型排名前3的分别为抗菌药物预防/治疗方案不合理、用药疗程不合理、给药途径和剂量不合理;2023年,抗菌药物不合理医嘱类型排名前3的分别为给药途径和剂量不合理、用药疗程不合理、抗菌药物预防/治疗方案不合理。结论 医院和科室上下联动事前-事中-事后闭环服务的抗菌药物管理模式可有效降低医院AUD,促进抗菌药物不合理医嘱类型的转变,从药物治疗方案优化逐步过渡到抗菌药物剂量和疗程精细化。 展开更多
关键词 医院和科室上下联动 事前-事中-事后闭环服务 抗菌药物 合理用药 抗菌药物使用强度 医嘱
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奖励-收集Steiner树问题的精确算法
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作者 曾宾 宁爱兵 +2 位作者 付振星 付馨懿 张惠珍 《系统管理学报》 CSCD 北大核心 2024年第5期1242-1250,共9页
奖励-收集Steiner树问题是图的Steiner最小树问题的衍生,同时也是组合优化中的NP-hard问题。首先,提出该问题的数学性质并给出证明,利用数学性质能降低该问题的规模;其次,基于该问题的数学性质设计出上下界子算法、降阶子算法和回溯子算... 奖励-收集Steiner树问题是图的Steiner最小树问题的衍生,同时也是组合优化中的NP-hard问题。首先,提出该问题的数学性质并给出证明,利用数学性质能降低该问题的规模;其次,基于该问题的数学性质设计出上下界子算法、降阶子算法和回溯子算法,通过上下界子算法和降阶子算法可以降低该问题解空间的规模,从而缩短回溯子算法的搜索时间,进而降低求解该问题最优解的时间;最后,应用案例分析、算例分析以及算法分析与对比表明,所设计的算法不仅可以求出该问题的最优解,而且比没有考虑该问题数学性质的一般回溯算法的时间复杂度更低。 展开更多
关键词 奖励-收集Steiner树 上下界子算法 降阶子算法 回溯子算法
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三水平逆耶茨序设计的低阶混杂性质
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作者 黄智赟 李智明 《应用概率统计》 CSCD 北大核心 2024年第3期452-462,共11页
在三水平正规设计中,低阶成分效应的混杂信息对选择最优设计至关重要.本文研究一类三水平逆耶茨序设计Dq(n),其中q为独立列个数,n为因子个数,得到设计Dq(n)在三种情况下低阶混杂信息的结果:(i)q<n<3q-1,n=2k,k∈N;(ii)q<n<3... 在三水平正规设计中,低阶成分效应的混杂信息对选择最优设计至关重要.本文研究一类三水平逆耶茨序设计Dq(n),其中q为独立列个数,n为因子个数,得到设计Dq(n)在三种情况下低阶混杂信息的结果:(i)q<n<3q-1,n=2k,k∈N;(ii)q<n<3q-1;n=2k+1;k∈N;(iii)3q-1≤n<(3q-1)/2.通过实例来演示上述结果. 展开更多
关键词 正规设计 逆耶茨序 别名成分数型 一般最小低阶混杂准则
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灾后应急配送中心选址问题的降阶回溯算法
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作者 胡开元 宁爱兵 +2 位作者 尹远翔 陈至伟 张惠珍 《物流科技》 2024年第16期1-5,共5页
近年来自然灾害频发,提高灾后应急物资的配送效率一直以来都是性命攸关的大事,因此文章基于灾后应急配送中心选址问题的精确算法进行研究。首先,建立该问题的数学模型并对该问题中的数学性质进行研究和证明;其次,在这些数学性质的基础上... 近年来自然灾害频发,提高灾后应急物资的配送效率一直以来都是性命攸关的大事,因此文章基于灾后应急配送中心选址问题的精确算法进行研究。首先,建立该问题的数学模型并对该问题中的数学性质进行研究和证明;其次,在这些数学性质的基础上,设计上下界子算法和降阶子算法,这些子算法能够有效减少解空间,提高算法的效率,使该算法能够更有效地处理规模更大的问题;再次,提出降阶回溯子算法,通过剪枝和局部降阶进一步缩小问题的搜索规模,并能得到最优解;最后,通过分析和解决一个案例来更清楚地说明算法的原理和操作步骤。 展开更多
关键词 应急配送中心选址问题 上下界算法 降阶回溯算法
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Direction finding of bistatic MIMO radar in strong impulse noise
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作者 CHEN Menghan GAO Hongyuan +2 位作者 DU Yanan CHENG Jianhua ZHANG Yuze 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期888-898,共11页
For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in ... For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in suppressing impulse noise and achieving superior direction finding performance using the maximum likelihood(ML)estimation method.A quantum equilibrium optimizer algorithm(QEOA)is devised to resolve the corresponding objective function for efficient and accurate direc-tion finding.The results of simulation reveal the capability of the presented method in success rate and root mean square error over existing direction-finding methods in different application situations,e.g.,locating coherent signal sources with very few snapshots in strong impulse noise.Other than that,the Cramér-Rao bound(CRB)under impulse noise environment has been drawn to test the capability of the presented method. 展开更多
关键词 bistatic multiple-input multiple-output(MIMO)radar impulse noise direction finding lower order covariance quan-tum equilibrium optimizer algorithm(QEOA) maximum likeli-hood estimation method Cramér-Rao bound(CRB)
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非光滑半无限多目标优化的高阶KKT最优性充分条件
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作者 曹琪 冯敏 《应用数学和力学》 CSCD 北大核心 2024年第4期502-508,共7页
考虑了一类非光滑半无限多目标优化问题.利用高阶Studniarski下导数,得到了问题的严格局部有效解的高阶弱KKT最优性充分条件.进一步地,若假设该最优性条件中目标函数相关的乘子均大于零,则得到严格局部Borwein真有效解的高阶强KKT充分条... 考虑了一类非光滑半无限多目标优化问题.利用高阶Studniarski下导数,得到了问题的严格局部有效解的高阶弱KKT最优性充分条件.进一步地,若假设该最优性条件中目标函数相关的乘子均大于零,则得到严格局部Borwein真有效解的高阶强KKT充分条件.这些充分条件适用于处理无任何凸性假设下的问题. 展开更多
关键词 半无限多目标优化 高阶Studniarski下导数 高阶KKT充分条件
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带有非强制性低阶项的变指标抛物问题
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作者 李春锦 许少鹏 《海南大学学报(自然科学版)》 CAS 2024年第2期111-120,共10页
研究了在穿孔域上带有变指数和带有低阶项的非线性抛物方程的重整化解的存在性结果.通过使用截断法,单调算子理论和正则化方法在变指数Sobolev空间的框架下解决了带有一个不具有强制性的低阶项的非线性抛物方程的重整化解的存在性问题.
关键词 重整化解 存在性 低阶项 变指数Sobolev空间
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有穷非整数下级整函数的唯一性
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作者 许爱珠 《宁德师范学院学报(自然科学版)》 2024年第2期113-117,共5页
证明有穷非整数下级整函数具有1个CM分担值和1个截断分担值的唯一性定理,改进已有的相关结果,并给出例子说明定理的条件是精确的.
关键词 整函数 下级 分担值 唯一性
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基于二阶滑模算法的步进电机自动升降转速控制方法
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作者 卓状 马博坤 +2 位作者 王珺 王昭 李凤 《现代制造技术与装备》 2024年第2期209-211,共3页
受各部分联动关系的影响,步进电机转速的升降调节控制效果难以满足实际需求。为此,提出基于二阶滑模算法的步进电机自动升降转速控制方法。在综合步进电机转子的运动方程、步进电机的电磁力矩方程、电机转动方程及阻尼系数方程的基础上... 受各部分联动关系的影响,步进电机转速的升降调节控制效果难以满足实际需求。为此,提出基于二阶滑模算法的步进电机自动升降转速控制方法。在综合步进电机转子的运动方程、步进电机的电磁力矩方程、电机转动方程及阻尼系数方程的基础上,构建步进电机数学模型,并明确通过调节输入电流,控制步进电机的转速,使得电机达到期望转速的控制目标。在具体的控制阶段,引入二阶滑模控制器,根据增益系数对滑模面函数和滑模控制律进行循环迭代,直至满足控制要求。测试结果表明,设计控制方法不仅能够实现在短时间内迅速调整测试步进电机转速,并且转速表现出较高的稳定性,满足实际应用需求。 展开更多
关键词 步进电机 自动升降 转速控制 二阶滑模控制器
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EXISTENCE AND UNIQUENESS FOR THIRD ORDER NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:5
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作者 WANG GUOCAN Department of Basic Science, Dalian Institute of Railway Technology, Dalian 116022 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期7-16,共10页
In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower soluti... In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower solutions. Our results improve someknown works. 展开更多
关键词 Third order nonlinear boundary value problem existence and uniqueness Volterra type operator upper and lower solutions.
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