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能量系统的热经济学分析的统一代数模式 被引量:1
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作者 蔡祥兴 陈文亮 杨东华 《能源技术》 1994年第2期10-15,共6页
本文系统地介绍了文献[2]所提出的 成本及热经济成本分析模式,并在数学形式的表达上使其更趋完善,引入了“热经济效益率”这一评价原则,并称其为能量系统的热经济学分析的统一代数模式。
关键词 能量系统 热经济学分析 代数模式
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代数应力模式的分析解及其在充分发展旋转管流中的应用 被引量:2
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作者 符松 《水动力学研究与进展(A辑)》 CSCD 北大核心 1994年第6期689-693,共5页
本文通过求解雷诺应力在代数应力模式中与平均速度梯度之间的分析关系,研究了代数应力模式在涡旋流动特别是在充分发展旋转管流中存在的内在缺陷,这些缺陷的主要表现为:(1)在不考虑固壁对湍流影响的代数应力模式中,分析解给出W... 本文通过求解雷诺应力在代数应力模式中与平均速度梯度之间的分析关系,研究了代数应力模式在涡旋流动特别是在充分发展旋转管流中存在的内在缺陷,这些缺陷的主要表现为:(1)在不考虑固壁对湍流影响的代数应力模式中,分析解给出W∝r和vw=0的错误结论;(2)若在代数应力模式中考虑固壁对湍流影响,在对称轴上会有v^2不等于w^2的非物理解。与诺应力输运模式相比。 展开更多
关键词 代数应力模式 旋转管流 管流水力学
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植被冠层湍流代数应力模式
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作者 张运福 储长树 《气象》 CSCD 北大核心 1996年第5期39-42,共4页
从植被冠层湍流时空平均雷诺应力方程出发,根据植被冠层内有关参数化的准则,建立了湍流代数应力模式,并用玉米和小麦两种作物地的实测资料对模式进行了验证。
关键词 植物冠层 参数化 代数应力模式 湍流
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Deep Web查询界面中的模式代数及其应用
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作者 赵靖 黄勇 宋雪亚 《现代计算机》 2010年第1期8-11,共4页
集成Web数据库的第一个挑战就是集成它们的查询界面。从类比于关系代数的角度来看,每一个界面都等价于一组基于L-树的模式。为集成这些模式获得全局模式,详细研究模式的定义和运算——模式代数,通过对其进行应用实践,表明模式代数能较... 集成Web数据库的第一个挑战就是集成它们的查询界面。从类比于关系代数的角度来看,每一个界面都等价于一组基于L-树的模式。为集成这些模式获得全局模式,详细研究模式的定义和运算——模式代数,通过对其进行应用实践,表明模式代数能较好地应用于异构相关Web查询主题的集成。 展开更多
关键词 DEEP WEB 模式 模式代数 WEB集成
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反映流动曲率影响的非线性湍流模式 被引量:5
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作者 钱炜祺 符松 《空气动力学学报》 CSCD 北大核心 2001年第2期203-209,共7页
本文从一般曲线坐标系下的雷诺应力模式出发 ,在雷诺应力模式向代数应力模式简化过程中 ,保留曲率项对雷诺应力输运的影响 ,得到了曲率修正的代数应力模式和非线性k ε模式。并用该模式对一典型曲率流动———U型管道内的湍流流动进行... 本文从一般曲线坐标系下的雷诺应力模式出发 ,在雷诺应力模式向代数应力模式简化过程中 ,保留曲率项对雷诺应力输运的影响 ,得到了曲率修正的代数应力模式和非线性k ε模式。并用该模式对一典型曲率流动———U型管道内的湍流流动进行了数值模拟与分析。计算结果显示 ,曲率修正的代数应力模式较好地模拟出了凸曲率对雷诺剪切应力的阻滞作用和凹曲率对剪切应力的增强作用 ,捕捉到了曲率流动的主要特征 。 展开更多
关键词 湍流 曲率 代数应力模式 工程湍流 飞行器 空气动力学
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超声速流动中非线性EASM湍流模式应用研究 被引量:2
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作者 姜宝森 张亮 +1 位作者 苏鹏辉 李俊红 《计算力学学报》 EI CAS CSCD 北大核心 2018年第1期117-122,共6页
针对超声速复杂流动区域精确模拟的需要,发展了基于k-ω可压缩修正形式的非线性显式代数雷诺应力模式(EASM),提高了该模式对超声速复杂流动的数值模拟精度。通过对二维超声速凹槽和三维双椭球的数值计算表明,与SA和SST常规线性涡黏性湍... 针对超声速复杂流动区域精确模拟的需要,发展了基于k-ω可压缩修正形式的非线性显式代数雷诺应力模式(EASM),提高了该模式对超声速复杂流动的数值模拟精度。通过对二维超声速凹槽和三维双椭球的数值计算表明,与SA和SST常规线性涡黏性湍流模式比较,非线性的EASM模式对大分离以及剪切层流动结构的刻画能力更精细,对剪切层再附区的压力及摩擦系数分布模拟更加精确;EASM模式能够准确地模拟二次激波引起的压强和热流分布情况。 展开更多
关键词 湍流模式 显示代数雷诺应力模式 可压缩修正 超声速流动 分离流动 剪切层
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用于弯管的计算机辅助纤维缠绕(英文) 被引量:8
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作者 李海晟 梁友栋 《软件学报》 EI CSCD 北大核心 2002年第4期518-525,共8页
纤维缠绕模式.在计算机辅助纤维缠绕中起着关键的作用,然而对于非轴对称纤维缠绕设计,目前还没有稳定、可靠的模式设计方法.另外,如何有效地处理纤维路径设计中产生的大量数据也是非轴对称纤维缠绕的一大难题.给出了用于弯管的纤维缠绕... 纤维缠绕模式.在计算机辅助纤维缠绕中起着关键的作用,然而对于非轴对称纤维缠绕设计,目前还没有稳定、可靠的模式设计方法.另外,如何有效地处理纤维路径设计中产生的大量数据也是非轴对称纤维缠绕的一大难题.给出了用于弯管的纤维缠绕模式和一种被称为节点存储法的新的数据处理方法. 展开更多
关键词 几何模式 代数模式 节点存储法 纤维缠绕 弯管 计算机辅助设计
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分布式天然气深冷分离装置的火用经济分析方法 被引量:1
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作者 王志国 尹柴玲 +2 位作者 宋明启 杜慧超 张利国 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2014年第8期1058-1062,共5页
针对能量分析和火用分析等用能分析方法存在一些不足,没有考虑系统运行的经济性.基于火用经济学的代数模式,提出了复杂系统的火用经济分析模型,给出了的系统—子系统—设备的火用经济分析过程.研究表明:根据天然气深冷分离装置特点,划分... 针对能量分析和火用分析等用能分析方法存在一些不足,没有考虑系统运行的经济性.基于火用经济学的代数模式,提出了复杂系统的火用经济分析模型,给出了的系统—子系统—设备的火用经济分析过程.研究表明:根据天然气深冷分离装置特点,划分为6个单元,建立系统和单元的火用经济平衡方程,给出火用经济分析评价指标;对于多个输入和输出物流,提出基于能级分摊的辅助方程建立方法.利用所建模型.对某NGL装置进行了火用经济分析,提出了合理调整压缩机及膨胀机的运行参数和应尽量使余热锅炉在满负荷下运行等措施,实际应用取得了较好效果. 展开更多
关键词 分布式NGL装置 火用经济分析 代数模式 火用平衡方程 分摊方法
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热经济学《连载》
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作者 杨东华 《能源研究与信息》 1989年第3期62-67,共6页
第九讲 热经济学(上) 热经济学是本世纪六十年代兴起的一门研究热系统经济运转的应用性学科,也是热力学和经济学两门学科结合而产生的一门边缘学科。 热经济学的研究对象是热系统的经济行为,因而是一门微观经济学。所谓热系统,乃是指它... 第九讲 热经济学(上) 热经济学是本世纪六十年代兴起的一门研究热系统经济运转的应用性学科,也是热力学和经济学两门学科结合而产生的一门边缘学科。 热经济学的研究对象是热系统的经济行为,因而是一门微观经济学。所谓热系统,乃是指它通过能量传递—转换,能对社会提供有用商品的一个技术组合实体。因此,动力装置、化工装置等均可视为这样的实体。 展开更多
关键词 热经济学 YONG经济学 代数模式
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Structural Carpentry in Qing Dynasty-A Framework for the Hierarchically Modularized Chinese Timber Structural Design 被引量:1
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作者 龚清宇 《Transactions of Tianjin University》 EI CAS 2002年第1期16-21,共6页
This article, by using mathematical expressions, offers a scientific framework for understanding how the grading system of Qing′s structural carpentry determines the design and construction in the grand style timber... This article, by using mathematical expressions, offers a scientific framework for understanding how the grading system of Qing′s structural carpentry determines the design and construction in the grand style timber architecture.The Qing′s grand style timber structure, which is ready for prefabrication and assembly, is extremely hierarchical oriented and significantly standardized. The general procedure in designing a grand style timber structure is to start with the grade that defines the basic module (dou kou); next comes with the number of bracket set (cuan), the number of longitudinal bays and the number of purlins which affect its plan and cross section; thirdly choose a roof type that determines its longitudinal section and the facade as well. A series of formulae are conducted to help depict the layout, cross sectional roof curvature and special longitudinal treatments in 4 sloped and 9 spined roofs respectively. 展开更多
关键词 structural carpentry mathematical expression grand style Qing Dynasty modular system Chinese timber structural design
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su(1,2) Algebraic Structure of XYZ Antiferromagnetic Model in Linear Spin-Wave Frame
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作者 JIN Shuo XIE Bing-Hao +1 位作者 YU Zhao-Xian HOU Jing-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1151-1154,共4页
The XYZ antiferromagnetic model in linear spin-wave frame is shown explicitly to have an su(1,2) algebraic structure: the Hamiltonian can be written as a linear function of the su(1,2) algebra generators. Based o... The XYZ antiferromagnetic model in linear spin-wave frame is shown explicitly to have an su(1,2) algebraic structure: the Hamiltonian can be written as a linear function of the su(1,2) algebra generators. Based on it, the energy eigenvalues are obta/ned by making use of the similar transformations, and the algebraic diagonalization method is investigated. Some numerical solutions are given, and the results indicate that only one group solution could be accepted in physics. 展开更多
关键词 XYZ antiferromagnetic model algebraic diagonalization method
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A K-Median Facility Location Agent for Low-Cost Service Selection in Digital Community Network
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作者 GAO Cong MA Jianfeng 《China Communications》 SCIE CSCD 2014年第11期174-186,共13页
With the increasing number of web services, it becomes a difficult task for an ordinary user to select an appropriate service. Hence, it is conventional that users in a digital community network take part in a collabo... With the increasing number of web services, it becomes a difficult task for an ordinary user to select an appropriate service. Hence, it is conventional that users in a digital community network take part in a collaborative mechanism for the purpose of service selection. The participation usually brings unnecessary burdens for users, such as giving opinions, storing service information. Extra communication overhead hinders the performance of the network. Thus, the community administrators are facing a problem of how to obtain an overall service selection result for the whole community readily and effectively. To address this problem, we present a k-median facility location agent model. The model analyzes the procedure of service selection through five entities and six types of messages. Two algorithms are elaborated in pursuit of a global optimization concerning connection costs between users and facilities where services are deployed. To evaluate our model, we conduct extensive simulations and present a detailed analysis of the simulation results. 展开更多
关键词 web services service selection k-median low cost service providers
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A SEMI-OPEN-LOOP CODING MODE SELECTION ALGORITHM BASED ON EFM AND SELECTED AMR-WB+ FEATURES
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作者 Hong Ying Zhao Shenghui Kuang Jingming 《Journal of Electronics(China)》 2009年第2期274-278,共5页
To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitatio... To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitation) classification are investigated.11 classifying features in the AMR-WB+ codec are selected and 2 novel classifying features,i.e.,EFM(Energy Flatness Measurement) and stdEFM(standard deviation of EFM),are proposed.Consequently,a novel semi-open-loop mode selection algorithm based on EFM and selected AMR-WB+ features is proposed.The results of classifying test and listening test show that the performance of the novel algorithm is much better than that of the AMR-WB+ semi-open-loop coding mode selection algorithm. 展开更多
关键词 Speech/Audio Semi-open-loop coding mode selection Features selection Energy Flat-ness Measurement(EFM)
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Brand Marketing in an era of big data
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作者 Shaozong Chai 《International Journal of Technology Management》 2014年第10期6-8,共3页
In the digital age, people' s lifestyles and ways of thinking are in a series of changes, this change also makes it a big shift in consumer attitudes. It gives consumers a broader perspective, while also improving th... In the digital age, people' s lifestyles and ways of thinking are in a series of changes, this change also makes it a big shift in consumer attitudes. It gives consumers a broader perspective, while also improving the self-consciousness of consumers. These effects will no longer fully believe in traditional consumer marketing "bombing" the dissemination and indoctrination, they are more inclined to be questioned brands and products, and they can express their views on the basis that affects other people. In this era of environment, if businesses and vendors for their view is indifferent attitude, they will lose a lot of attention to the crowd, and also it makes the influence of the traditional marketing model spread greatly reduced. 展开更多
关键词 big data BRAND MARKETING
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统一性的联想与类比
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作者 肖建辉 《中学生数学(初中版)》 2006年第16期7-8,共2页
一、三角形面积公式统一性三角形的面积公式:S=1/2ah.其中a是一边的长,称作底,h是这边上的高,简称高.三角形的另一个面积公式:S=1/2pr.其中p是三角形的周长,可视为“底”,是“周底”;r是三角形的内切圆的半径,可视为“高”.
关键词 直角三角形 面积公式 勾股定理 切割线定理 代数模式 射影定理
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Determinant formula and a realization for the Lie algebra W(2,2)
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作者 Wei Jiang Yufeng Pei Wei Zhang 《Science China Mathematics》 SCIE CSCD 2018年第4期685-694,共10页
In this paper, an explicit determinant formula is given for the Verma modules over the Lie algebra W(2, 2). We construct a natural realization of a certain vaccum module for the algebra W(2, 2) via the Weyl vertex alg... In this paper, an explicit determinant formula is given for the Verma modules over the Lie algebra W(2, 2). We construct a natural realization of a certain vaccum module for the algebra W(2, 2) via the Weyl vertex algebra. We also describe several results including the irreducibility, characters and the descending filtrations of submodules for the Verma module over the algebra W(2, 2). 展开更多
关键词 Lie algebra Verma module highest weight representation W(2 2) algebra vertex algebra
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Trivial module for ortho-symplectic Lie superalgebras and Littlewood's formula
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作者 CAO BinTao LUO Li 《Science China Mathematics》 SCIE 2013年第11期2251-2260,共10页
We show that the denominator identity for ortho-symplectic Lie superalgebras 0sp(kl2n) is equiva- lent to the Littlewood's formula. Such an equivalence also implies the relation between the trivial module and gener... We show that the denominator identity for ortho-symplectic Lie superalgebras 0sp(kl2n) is equiva- lent to the Littlewood's formula. Such an equivalence also implies the relation between the trivial module and generalized Verma modules for op(kl2n). Furthermore, we discuss the harmonic representative elements of the Kostant's u-cohomology with trivial coefficients. 展开更多
关键词 ortho-symplectic superalgebra denominator identity Kostant's u-cohomology
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Multiple weighted estimates for commutators of multilinear fractional integral operators 被引量:2
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作者 CHEN SongQing WU HuoXiong 《Science China Mathematics》 SCIE 2013年第9期1879-1894,共16页
Multilinear commutators and iterated commutators of multilinear fractional integral operators with BMO functions are studied. Both strong type and weak type endpoint weighted estimates involving the multiple weights f... Multilinear commutators and iterated commutators of multilinear fractional integral operators with BMO functions are studied. Both strong type and weak type endpoint weighted estimates involving the multiple weights for such operators are established and the weak type endpoint results are sharp in some senses. In particular, we extend the results given by Cruz-Uribe and Fiorenza in 2003 and 2007 to the multilinear setting. Moreover, we modify the weak type of endpoint weighted estimates and improve the strong type of weighted norm inequalities on the multilinear commutators given by Chen and Xue in 2010 and 2011. 展开更多
关键词 multilinear fractional integrals COMMUTATORS maximal operators multiple weights A P q weighted norm inequalities
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Differential-operator representations of Weyl group and singular vectors in Verma modules
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作者 Wei Xiao 《Science China Mathematics》 SCIE CSCD 2018年第6期1013-1038,共26页
Given a suitable ordering of the positive root system associated with a semisimple Lie algebra,there exists a natural correspondence between Verma modules and related polynomial algebras. With this, the Lie algebra ac... Given a suitable ordering of the positive root system associated with a semisimple Lie algebra,there exists a natural correspondence between Verma modules and related polynomial algebras. With this, the Lie algebra action on a Verma module can be interpreted as a differential operator action on polynomials, and thus on the corresponding truncated formal power series. We prove that the space of truncated formal power series gives a differential-operator representation of the Weyl group W. We also introduce a system of partial differential equations to investigate singular vectors in the Verma module. It is shown that the solution space of the system in the space of truncated formal power series is the span of {w(1) | w ∈ W }. Those w(1) that are polynomials correspond to singular vectors in the Verma module. This elementary approach by partial differential equations also gives a new proof of the well-known BGG-Verma theorem. 展开更多
关键词 Verma module singular vector differential equation differential operator Weyl group
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Development of Six-sigma Capability Indices in Modern Quality Management Practices
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作者 Abdul Sattar Jamali Jinlin Li 《Journal of Systems Science and Information》 2006年第1期127-133,共7页
This research work based on the development of 6σ capability indices in the Modern Quality Management Practices in the world level companies is briefly introduced. The process performance index (when a process indic... This research work based on the development of 6σ capability indices in the Modern Quality Management Practices in the world level companies is briefly introduced. The process performance index (when a process indicated by control charts is under control) and the percentage of defective products are calculated and compared with kσ. Finally, compared 6σ with 3σ, when process is on nominal (nominal - mean), the process has 1.5σ shift from nominal. 展开更多
关键词 six-sigma capability indices parts per million
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