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2-complex Symmetric Weighted Composition Operators on Fock Space of C^(N)
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作者 JIANG Zhijie 《数学进展》 北大核心 2025年第1期37-49,共13页
The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(... The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given. 展开更多
关键词 Fock space weighted composition operator 2-complex symmetric operator reproducing kernel function
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The Properties of the Shear Gradient Operator and Its Application in Image Deblurring
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作者 LIU Xiaofeng LU Lixuan ZHANG Tao 《Wuhan University Journal of Natural Sciences》 2025年第5期427-440,共14页
The utilization of gradient operators is prevalent in image processing,as they effectively detect edges and provide directional information.However,these operators only differentiate the horizontal and vertical direct... The utilization of gradient operators is prevalent in image processing,as they effectively detect edges and provide directional information.However,these operators only differentiate the horizontal and vertical directions,ignoring details and causing loss of information in other directions.This paper introduces the shear gradient operator to overcome this limitation by capturing details accurately in multiple directions.It investigates the properties of the shear gradient operator and proposes the shear total variation(STV)norm for image deblurring.By combining non-convex regularization to avoid excessive penalty and retain image details,a novel deblurring model integrating the STV norm and the L_(1)/L_(2) minimization is proposed.The alternating direction method of multipliers(ADMM)algorithm is employed to solve this computationally challenging model,demonstrating exceptional performance in non-blind image deblurring through experiments. 展开更多
关键词 shear gradient operator shear total variation norm image deblurring alternating direction method of multipliers(ADMM) L_(1)/L_(2)minimization
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食品级二氧化碳装置脱烃催化剂的运行总结
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作者 陈健 胡燕 +7 位作者 杨同 徐美楠 魏华 孟坚 罗毅 胡磊 沈建冲 刘华伟 《化工设计通讯》 2026年第2期7-12,共6页
文章总结了近五年国内三套典型食品级二氧化碳装置脱烃催化剂的最新运行情况。三套装置均采用杭州快凯高效节能新科技有限公司和华烁科技股份有限公司联合开发的食品级二氧化碳全套工艺包,以及华烁科技股份有限公司的专利产品THC-2型脱... 文章总结了近五年国内三套典型食品级二氧化碳装置脱烃催化剂的最新运行情况。三套装置均采用杭州快凯高效节能新科技有限公司和华烁科技股份有限公司联合开发的食品级二氧化碳全套工艺包,以及华烁科技股份有限公司的专利产品THC-2型脱烃催化剂。脱烃装置稳定运行的结果表明,在操作温度为360~400℃时,脱烃塔出口总烃含量<20×10^(-6),苯含量<10×10^(-9),满足食品级二氧化碳的质量指标要求。此外,催化剂操作弹性大、稳定性好,部分装置的催化剂运行寿命已超过4 a且仍能正常使用。 展开更多
关键词 THC-2型脱烃催化剂 食品级二氧化碳 运行数据
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面向使用需求的舰船气流场模糊综合评价方法
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作者 陈成 张修远 +3 位作者 张祥瑞 常选明 何秦 王勤 《哈尔滨工程大学学报》 北大核心 2026年第1期182-192,共11页
当前舰船气流场特性评价方法存在系统性和合理性不足问题,无法为复杂舰船装备气流场方案评估决策提供可靠支撑。本文构建面向使用需求的舰船气流场特性评价指标体系,将经典层次分析法及逼近理想解法拓展到区间二型模糊群决策情境,并提... 当前舰船气流场特性评价方法存在系统性和合理性不足问题,无法为复杂舰船装备气流场方案评估决策提供可靠支撑。本文构建面向使用需求的舰船气流场特性评价指标体系,将经典层次分析法及逼近理想解法拓展到区间二型模糊群决策情境,并提出几何一致性改进算法及模糊包络体性能评估方法。通过“美国”级两栖攻击舰气流场方案综合评价实例,验证所提方法的可行性及有效性。研究结果为舰船气流场特性评价提供思路和方法。 展开更多
关键词 舰船设计 气流场 综合评价 多属性群决策 区间二型模糊集 使用需求 一致性验证 模糊包络体
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基于多目标优化的船舶柴油发电机组并网策略
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作者 韩健 丁宇 +3 位作者 陈斯文 刘国政 王瑞 随从标 《哈尔滨工程大学学报》 北大核心 2026年第2期407-415,490,共10页
为了研究一种高效且环保的邮轮柴油发电机组并网策略,本文构建以CO_(2)排放、NO_(x)排放和并网时间为多目标的优化模型,采用多目标遗传算法进行求解,并结合层次分析法与熵权法构建的综合权重TOPSIS方法,给出了典型负荷区间的最优并网调... 为了研究一种高效且环保的邮轮柴油发电机组并网策略,本文构建以CO_(2)排放、NO_(x)排放和并网时间为多目标的优化模型,采用多目标遗传算法进行求解,并结合层次分析法与熵权法构建的综合权重TOPSIS方法,给出了典型负荷区间的最优并网调度方案。研究结果表明所提出策略在中高负荷下的3个目标值显著优于传统下垂控制策略,在整个负荷区间内CO_(2)与NO_(x)排放分别平均降低3.01、1.29 g(kW·h),并网时间也显著缩减,且并网过程中机组转速波动率控制在0.3%以内。本研究表明基于多目标遗传算法的并网优化策略兼具环保性与动态响应优势,可为邮轮机组的并网控制策略设计提供理论支持与工程参考。 展开更多
关键词 多目标遗传算法 柴油发电机组并网 能量管理系统 船舶电力推进系统仿真 CO_(2)排放 NO_(x)排放 并网时间 转速波动率
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2型犹豫q阶三角不确定语言Schweizer-Sklar-Muirhead算子
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作者 吕笑凡 袁修久 +1 位作者 李京泰 赵学军 《山东大学学报(理学版)》 北大核心 2026年第1期116-126,共11页
为了描述多属性决策问题中决策者们多层的犹豫性,本文结合犹豫模糊集、q阶三角犹豫模糊集和q阶犹豫模糊不确定语言集,提出2型犹豫q阶三角不确定语言集,定义了基于Schweizer-Sklar范数的模糊元的运算,证明运算的性质。为了有效处理评估... 为了描述多属性决策问题中决策者们多层的犹豫性,本文结合犹豫模糊集、q阶三角犹豫模糊集和q阶犹豫模糊不确定语言集,提出2型犹豫q阶三角不确定语言集,定义了基于Schweizer-Sklar范数的模糊元的运算,证明运算的性质。为了有效处理评估属性之间相互关联的现实决策问题,将Muirhead平均算子推广至2型犹豫q阶三角不确定语言集,提出2型犹豫q阶三角不确定语言Schweizer-Sklar-Muirhead平均算子和加权Muirhead平均算子,并给出这些算子的计算公式和性质。最后,给出基于2型犹豫q阶三角不确定语言Muirhead平均算子的多属性决策方法,并进行算例分析。 展开更多
关键词 犹豫模糊集 2型犹豫q阶三角不确定语言集 Muirhead平均算子 多属性决策
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燃煤半闭式超临界二氧化碳发电系统变工况性能分析
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作者 郭豪 许宏宇 +2 位作者 韩禹 辛团团 许诚 《中国电机工程学报》 北大核心 2026年第2期715-726,I0022,共13页
为实现超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))发电系统在较宽负荷区间内的灵活高效运行,该文构建燃煤半闭式S-CO_(2)发电系统变工况模型,研究系统在透平全周进气、背压恒定且出口温度不变的基础变工况运行模式下的部... 为实现超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))发电系统在较宽负荷区间内的灵活高效运行,该文构建燃煤半闭式S-CO_(2)发电系统变工况模型,研究系统在透平全周进气、背压恒定且出口温度不变的基础变工况运行模式下的部分负荷性能;通过透平部分进气调节和背压调节实现系统参数的优化,最终提出部分进气度和背压相协同的新型高效变负荷运行方法。结果表明,在低负荷区间运行时,单独减小部分进气度或单独降低背压均可提高系统净效率,但在高负荷区间内,减小部分进气度或过度降低背压会产生相反效果;通过采用透平部分进气和背压相协同的调节方法,可以在低负荷区间内进一步提升系统净效率。针对600 MWe等级机组,在30%负荷时,系统净效率可达34.77%,较基础变工况运行模式提高了3.8个百分点。 展开更多
关键词 超临界二氧化碳循环 富氧燃烧 零碳排放 变工况性能 运行策略
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基于二型模糊预序的模糊粗糙集模型
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作者 张光旭 姚卫 《山东大学学报(理学版)》 北大核心 2026年第1期85-93,共9页
以二型模糊预序为基本结构研究了模糊粗糙集,定义一对模糊上下近似算子,并研究它们的性质和相互关系,证明上可定义集和下可定义集是等价的,上可定义集和下可定义集构成一个满层的Alexandrov模糊拓扑。
关键词 二型模糊预序 模糊粗糙集 模糊近似算子 可定义集 Alexandrov模糊拓扑
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某地浸采铀矿山钻孔过滤器长度与浸出参数的关系
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作者 赵生祥 闫纪帆 +1 位作者 口文杰 舒倪楚庭 《铀矿冶》 2026年第1期76-81,共6页
聚焦钱家店铀矿床“CO_(2)+O_(2)”地浸采铀工艺,深入探究过滤器长度与浸采率、抽液量之间的关系。基于实际运行数据进行分析,得出过滤器长度与抽液量呈强正相关,在过滤器长度为7~11 m时,随过滤器长度增加,抽液量增长显著(平均增长率5.2... 聚焦钱家店铀矿床“CO_(2)+O_(2)”地浸采铀工艺,深入探究过滤器长度与浸采率、抽液量之间的关系。基于实际运行数据进行分析,得出过滤器长度与抽液量呈强正相关,在过滤器长度为7~11 m时,随过滤器长度增加,抽液量增长显著(平均增长率5.2%/m);在过滤器长度为12~18 m时,随过滤器长度增加,抽液量增长放缓(平均增长率1.3%/m)。过滤器长度与浸采率呈强负相关,在过滤器长度为7~11 m时,随过滤器长度增加,浸采率下降平缓(平均降幅0.75%/m);在过滤器长度为12~14 m时,随过滤器长度增加,浸采率降幅增大(平均降幅2.0%/m);在过滤器长度为15~18 m时,随过滤器长度增加,浸采率大幅下降(平均降幅3.67%/m)。根据研究结果,建议在钱家店铀矿床“CO_(2)+O_(2)”地浸采铀工艺中,过滤器长度宜优先采用7~9 m的最优区间;对于矿体厚度较大的矿段,可在16 m范围内适当调整,但不应超过16 m。 展开更多
关键词 钱家店铀矿床 “CO_(2)+O_(2)” 地浸采铀 过滤器长度 浸采率 抽液量
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内脏脂肪面积联合性别预测腹腔镜胃旁路手术时长的临床价值
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作者 曾松华 黄红艳 +2 位作者 汪蕾 吴慧 吴良平 《广东医学》 2026年第1期29-33,共5页
目的探讨内脏脂肪面积(VFA)对腹腔镜Roux-en-Y胃旁路术(LRYGB)手术时长的预测价值,为优化肥胖合并2型糖尿病(T2DM)患者的手术规划提供依据。方法回顾性分析47例肥胖T2DM患者(BMI≥27.5 kg/m^(2))的临床资料,通过人体成分分析仪(Inbody2... 目的探讨内脏脂肪面积(VFA)对腹腔镜Roux-en-Y胃旁路术(LRYGB)手术时长的预测价值,为优化肥胖合并2型糖尿病(T2DM)患者的手术规划提供依据。方法回顾性分析47例肥胖T2DM患者(BMI≥27.5 kg/m^(2))的临床资料,通过人体成分分析仪(Inbody230)测定术前VFA等指标,记录手术时长及并发症。以15例非肥胖T2DM患者(BMI<27.5 kg/m^(2))为对照,采用Spearman相关分析VFA与手术时长的相关性,多因素线性回归识别影响因素,ROC曲线确定VFA预测手术时长及联合性别预测的效能。结果肥胖组VFA显著高于对照组(P<0.05),且女性VFA高于男性[(131.07±34.44)cm^(2)vs.(112.79±15.44)cm^(2),P=0.029];手术时长与VFA呈显著正相关(r=0.443,P<0.01),多因素回归显示VFA是手术时长的独立影响因素(P<0.05);VFA预测手术时长的ROC曲线下面积(AUC)为0.689(95%CI:0.538~0.840,敏感度91.67%,特异度39.13%);联合性别预测时AUC提升至0.808(95%CI:0.684~0.932,敏感度66.67%,特异度82.67%)。结论VFA是LRYGB手术时长的独立预测因子,联合性别可显著提高预测准确性。建议术前将VFA(尤其女性患者)纳入风险评估体系,以优化手术资源配置及临床路径管理。 展开更多
关键词 内脏脂肪面积 腹腔镜Roux-en-Y胃旁路术 手术时长 预测价值 2型糖尿病 肥胖症
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燃气锅炉掺氢燃烧、排放及运行特性研究
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作者 邢永杰 冯浩男 +4 位作者 鲁军辉 温朝朝 杨文慧 张晓瑞 郭帅杰 《暖通空调》 2026年第1期70-77,共8页
燃气锅炉掺氢燃烧是城镇供热减少碳排放的重要途径,但针对燃气锅炉掺氢燃烧、排放及运行特性的研究较少。本文分析了掺氢比对燃气锅炉各项运行参数的影响,探讨了掺氢天然气的物性参数变化、燃烧与排放特性及锅炉运行优化策略。结果显示... 燃气锅炉掺氢燃烧是城镇供热减少碳排放的重要途径,但针对燃气锅炉掺氢燃烧、排放及运行特性的研究较少。本文分析了掺氢比对燃气锅炉各项运行参数的影响,探讨了掺氢天然气的物性参数变化、燃烧与排放特性及锅炉运行优化策略。结果显示:掺氢天然气可显著降低CO_(2)排放,但其物性参数的显著变化需重新调整燃烧参数以维持锅炉效率;掺氢比增大会加速层流火焰传播速度,扩大可燃极限,并提升火焰温度,导致热力型NO_(x)排放量增大(尤其在温度高于1600 K时);通过调节过量空气系数可抑制NO_(x)生成,但高掺氢比(>50%)时效果减弱;现有研究多聚焦小型家用锅炉(25~28 kW),证实掺氢可提升冷凝效率及节能潜力,但大容量工业锅炉的高掺氢运行数据仍匮乏。 展开更多
关键词 燃气锅炉 掺氢燃烧 掺氢比 燃烧特性 排放特性 运行特性 NOX排放 CO_(2)排放
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GENERALIZED OPERATORS AND P(φ)_2 QUANTUM FIELDS 被引量:1
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作者 黄志远 让光林 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期589-596,共8页
In this paper by Sobolev imbedding theorem and characterization theorem of generalized operators the existence of P(φ)2 quantum fields as generalized operators is obtained and a rigorous mathematical interpretation o... In this paper by Sobolev imbedding theorem and characterization theorem of generalized operators the existence of P(φ)2 quantum fields as generalized operators is obtained and a rigorous mathematical interpretation of renormalization procedure is given under white noise theory. 展开更多
关键词 White noise calculus generalized operator P(φ)2 quantum fields
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THE EXISTENCE AND BLOW-UP OF THE RADIAL SOLUTIONS OF A(k_(1),k_(2))-HESSIAN SYSTEM INVOLVING A NONLINEAR OPERATOR AND GRADIENT 被引量:1
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作者 Guotao WANG Zedong YANG +1 位作者 Jiafa XU Lihong ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第4期1414-1426,共13页
In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=... In this paper,we are concerned with the existence of the positive bounded and blow-up radial solutions of the(k1,k2)-Hessian system■where G is a nonlinear operator,Ki=Ski(λ(D^(2) z_(i)))+ψ_(i)(|x|)|▽_(zi)|^(ki),i=1,2.Under the appropriate conditions on gi and g2,our main results are obtained by using the monotone iterative method and the Arzela-Ascoli theorem.Furthermore,our main results also extend the previous existence results for both the single equation and systems. 展开更多
关键词 (k_(1) k_(2))-Hessian system nonlinear operator BLOW-UP monotone iterative method GRADIENT
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New 3-mode bosonic operator realization of SU(2) Lie algebra:From the point of view of squeezing
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作者 笪诚 陈千帆 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期62-64,共3页
We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±,... We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±, Jz) from the point of view of squeezing we find that (J±,Jz) can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation (the eigenvectors of J+ or J-) of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU(2) transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU(2) and new squeezing operators. 展开更多
关键词 quantum mechanical SU(2) transformation 3-mode squeezing operator new 3-mode bosonic op-erator realization of SU(2) Lie algebra
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Projection Operator on Rational Noncommutative Orbifold T^2/Z_4
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作者 冯俊 杨战营 +2 位作者 张凯 侯伯宇 石康杰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期107-118,共12页
In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator P on the rational noncommutative orbifold T^2/Z_4.we give the closed form for the pr... In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator P on the rational noncommutative orbifold T^2/Z_4.we give the closed form for the projector by Jacobi elliptical functions. Since projectors correspond to soliton solutions of the field theory on the noncommutative orbifold, we thus present a corresponding soliton solution. 展开更多
关键词 SOLITON projection operator noncommutative orbifold T2/Z4
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Some Properties of Causal Linear Time-Invariant(LTI) Operators on the Weighted l_(2) Space
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作者 Naifeng GAN Yufeng LU Liu LIU 《Journal of Mathematical Research with Applications》 CSCD 2015年第6期672-680,共9页
We discuss the properties of causal LTI operators on weighted ?2 spaces for different choices of the weighting sequence {w(t)}t∈Z. Problems of closability of unstable causal LTI convolution operators are also disc... We discuss the properties of causal LTI operators on weighted ?2 spaces for different choices of the weighting sequence {w(t)}t∈Z. Problems of closability of unstable causal LTI convolution operators are also discussed. We shall provide a new type of argument concerning causal LTI operators and robust design that can be applied to a large class of weighted ?2 spaces on Z. 展开更多
关键词 causal LTI operators weighted l_(2) space two-operator approach
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The two-mode quantum Fresnel operator and the multiplication rule of 2D Collins diffraction formula
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作者 谢传梅 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期296-300,共5页
By using the two-mode Fresnel operator we derive a multiplication rule of two-dimensional (2D) Collins diffraction formula, the inverse of 2D Collins diffraction integration can also be conveniently derived in this ... By using the two-mode Fresnel operator we derive a multiplication rule of two-dimensional (2D) Collins diffraction formula, the inverse of 2D Collins diffraction integration can also be conveniently derived in this way in the context of quantum optics theory. 展开更多
关键词 2D Collins diffraction formula two-mode Fresnel operator
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Residual Operator of Type-2 Triangular Norms on Convex Normal Upper Semi-Continuous Fuzzy Truth Values
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作者 Xinxing WU Shuangfeng LUO +1 位作者 Zhiyi ZHU Lidong WANG 《Journal of Mathematical Research with Applications》 CSCD 2024年第3期285-290,共6页
Based on the residual implication of continuous triangular norms,we obtain the expression of residual operator for extended operators(type-2 triangular norms)of continuous triangular norms on convex normal upper semi-... Based on the residual implication of continuous triangular norms,we obtain the expression of residual operator for extended operators(type-2 triangular norms)of continuous triangular norms on convex normal upper semi-continuous fuzzy truth values,answering an open problem in[D.LI,Inf.Sci.,2015,317:259-277]. 展开更多
关键词 type-2 fuzzy set triangular norm(t-norm) residual operator
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THE L^2-BOUNDEDNESS OF PSEUDODIFFERENTIAL OPERATORS WITH NONSMOOTH COEFFICIENT SYMBOLS
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作者 李得宁 《Acta Mathematica Scientia》 SCIE CSCD 1989年第1期1-5,共5页
1. Introduction In application of nonlinear boundary value problems, it is sometimes important to know that L~2-boundedness of a class of pseudo-differential operators with symbols whioh have nonsmooth coefficients. I... 1. Introduction In application of nonlinear boundary value problems, it is sometimes important to know that L~2-boundedness of a class of pseudo-differential operators with symbols whioh have nonsmooth coefficients. In [2], Coifman and Meyer proved that the operator σ(x, D) is bounded in L~2(R~n) if its symbold (x, ξ) satisfies: 展开更多
关键词 TH THE L~2-BOUNDEDNESS OF PSEUDODIFFERENTIAL operatorS WITH NONSMOOTH COEFFICIENT SYMBOLS
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Eigenfunction expansion method of upper triangular operator matrixand application to two-dimensional elasticity problems based onstress formulation
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作者 额布日力吐 阿拉坦仓 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第2期223-232,共10页
This paper studies the eigenfunction expansion method to solve the two dimensional (2D) elasticity problems based on the stress formulation. The fundamental system of partial differential equations of the 2D problem... This paper studies the eigenfunction expansion method to solve the two dimensional (2D) elasticity problems based on the stress formulation. The fundamental system of partial differential equations of the 2D problems is rewritten as an upper tri angular differential system based on the known results, and then the associated upper triangular operator matrix matrix is obtained. By further research, the two simpler com plete orthogonal systems of eigenfunctions in some space are obtained, which belong to the two block operators arising in the operator matrix. Then, a more simple and conve nient general solution to the 2D problem is given by the eigenfunction expansion method. Furthermore, the boundary conditions for the 2D problem, which can be solved by this method, are indicated. Finally, the validity of the obtained results is verified by a specific example. 展开更多
关键词 eigenfunction expansion method two-dimensional (2D) elasticity problem upper triangular operator matrix general solution
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