结构方程
- 与 结构方程 相关的网络例句 [注:此内容来源于网络,仅供参考]
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One method was unstructured grid transformed from structured grid, which was created by numerically solving the elliptic partial differential equation.
提出两种非结构化网格生成方法,一种是由结构网格转化为非结构网格,结构化网格的生成是用椭圆型偏微方程法。
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It was found that the residual pulsant Reynolds stress term of coherent structures has the same order of magnitude with the Reynolds stress contribution term of random fluctuation and can not be ignored in the dynamic model of coherent structures. This is not as that estimated before.
研究发现,相干结构剩余脉动雷诺应力项在数值上具有和随机脉动对相干结构贡献的雷诺应力相同的数量级,表明在相干结构动力学模型方程中,相干结构剩余脉动雷诺应力项并不像以前佑计的那样可以忽略不计。
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On the ground of simple compression test, a damage equation which reflect structural strength change with pressure is carried out. And it discriminated from the strain types of common soft soil and structural soft soil.
通过分析计算,明确了先期固结压力和结构强度的概念;提出了结构稳定系数,较为准确地判断出土的结构强度的影响程度,为工程设计提供参考;④基于单向压缩试验,提出了结构强度随压力变化的损伤方程;区分了一般性软土与有结构强度的土的压密类型。
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In chapter 1, an up to now synthetically evaluation is given on the research ways and conclusions about jet in cross-flow. Considering the shortage of previous research ways and techniques (the instantaneous flow field and vortices field can not be properly get), in addition to the deficiency of corresponding conclusion (mainly concentrate on the analysis of time-average but little on structures of flow and action of vortex), the research way and content is draft out in this part. Though PIV, the time-average, instantaneous flow field and vortices field can be get, that will unveil the coherent vortex and its course of generation, development and evolvement, with the assistance of K-ε model and Hybrid Finite Analytic Method , which will proof-test the experiment result and bring some complementary, more profound research about the 3-D characters can be done. Using some fundamental topological theory and principle on flow analysis, with anglicizing of vortex structure, a reasonable description is the topological characteristic of near field in JICF given.
首先在第一章中对横流中湍射流的以往研究方法和研究成果给予了综合的评述,针对横流中湍射流旋涡结构以往研究中研究方法的局限性(不能很好得到流动的瞬态流场及涡量场)和相应研究成果中存在的不足(大都集中在时均特性的分析,对流动的内部结构和旋涡的运动阐述很少),明确了本文的研究方法和研究内容:通过PIV流动测量显示技术得到流动的时均及瞬态流场、涡量场,来揭示横流中湍射流的时均、瞬态流场、涡量分布特性,和各种具有拟序结构性质的复杂涡系的产生、发展及演化过程;结合湍流k-ε双方程模型及相应的HFAM计算方法,对于实验进行相互验证和补充,从而更为充分地研究各种旋涡的三维特性;利用拓扑分析的一些基本原理及相关规则,依据对各种旋涡结构的分析,做出对射流近区流场拓扑性质的合理描述。
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The deformation compatible equation based on the catenary cable element is derived in chapter 2, and corresponding program is made to solve the accurate distribution of the prestress for cable dome. During the solving, two-nodes bar elements and catenary elements are adopted for the struts and cables of structure respectively. As the cable dome is a kinematically indeterminate system, its solving process is also derived in detail and the equations, which are based on large distortion, are adopted to solve the problem.
第二章推导了基于悬链线解析解的索单元变形协调方程式,并编制了相应计算程序对索穹顶结构精确的预应力分布进行求解,结构分析时压杆采用两节点直线杆单元,索采用悬链线索单元;考虑到索穹顶结构属于动不定结构体系,文中还对动不定体系的求解过程进行了详细的推导,同时采用建立在大变形基础上的变形协调方程来求解结构体系的有限机构位移。
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With the support of a major research grant of Zhejiang Province (No. 001101027) and the Plan of Promoting Education of Excellence of Zhejiang University in the 21st Century, this dissertation is devoted to address the above problems and fabricate an L-band EDFA with low cost, high performance and technological innovation.First the mechanism of an erbium doped fiber amplifier is introduced. Various theoretical models based on classical rate propagation equations are summarized and compared for their applications. We use a modified numerical model based on the Giles model, which agrees with the experimental results well. This serves as the theoretical base for the whole thesis and will be used to optimize the characteristics of EDFAs. A novel method based on a map of noise figure and gain is proposed to analyze efficiently the dependence of the noise figure and gain for EDFAs on the EDF length and the pump power. The characteristics of various EDFAs are studied and compared.Secondly, some important parameters are introduced to describe the characteristics of EDFAs. The methods and the experimental setups for measuring the gain and noise figure of an EDFA are emphasized. We introduce how to measure the characteristics of each component of an EDFA, especially the gain and absorption coefficient of an erbium doped fiber.Thirdly, four types of simple and novel L-band EDFA structures with low noise, high gain and low gain ripple are proposed to satisfy the requirement of a DWDM system. They can be classified into two categories. In the first category, a single ASE pumping is served asa secondary pump. This category includes the following three types. Type: a new construction using a fiber Bragg grating in an unpumped EDF section at the input side. Type: a new structure of L-Band EDFA with two-stage pumps, which utilizes the forward ASE as a second pump.
本论文本着科技创新、服务于生产实践的精神,以设计价格低廉,性能优越、结构合理简单的L-band EDFA为目标,依托浙江省科技厅重大科学基金资助项目(001101027)和浙江大学振兴教育计划资助的全光网络的搭建—《光通信技术》课程实验建设项目,展开了如下工作:首先,介绍了掺铒光纤放大器的工作原理,归纳总结了基于速率方程基础的EDFA的各种理论模型,分析比较了各个模型的特点和适用场合,最终选择完善的Giles理论模型作为本论文分析设计EDFA的理论基础;针对实际实验条件提出了修正的EDFA模型的数值计算方法;创新地提出了增益—噪声系数全局分析法,直观有效地分析了EDFA的增益和噪声系数与掺铒光纤长度和泵浦功率的依赖关系,并对各种EDFA的性能作了全面的比较;第二,介绍了掺铒光纤放大器特性参数的定义与测量方法,重点介绍了噪声系数和增益系数的测量方法及实验装置;介绍了组成掺铒光纤放大器各组件的特性测量方法,重点介绍了测量掺铒光纤参数的方法和实验装置;第三,针对WDM系统对L-band EDFA谱平坦、低噪声、高增益的要求,我们创新地提出了四种不同的L-band EDFA结构,按设计思路可以分为两大类:一类是基于单抽运二级泵浦法,这一类包括在未泵浦掺铒光纤的输入端插入一根布拉格光纤光栅的两段L-band的EDFA的新结构;基于前向ASE光作为二级泵浦源推动下一级EDF工作的泵浦分配、两段级联L-band的EDFA的新结构;基于单根光纤光栅、泵浦分配、两段级联的EDFA;另一类则是基于同时应用前后向C-band ASE作二级泵浦源的双抽运法,如基于前后向ASE光作为二级泵浦源的三段级联L-band的EDFA的新结构。
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Its rule of change was obtained. On the basis of other studies, the flocculation kinetics and flocs structure was studied. By making some assumptions, collision frequency were presented. Then the the flocculation kinetics model was established through population balance equation. Comparison of experimental data and modeling results indicate that there are the same trend between the two. So the model can predict flocs number and size during flocculation of Yellow River's loess particles without using empirical parameters. The TEM and SEM were used to obsever flocs in the study of floc structure. The flocculation was divided as flocculi, floc and floc aggregate. The flocs structure model was established by assumption that particles position in floc accords with tetrahedron. The fractal dimension of model and experimental flocs was found to be coincident. So the model can reflect the structure of flocs formed in flocculation of Yellow River's loess particles by macromolecule flocculant at a certain extent.
最后,本文还对絮凝动力学和絮体结构进行了研究,在前人研究的基础上,针对高分子絮凝黄河泥沙,对絮凝过程作了一些符合试验条件的假设,建立了颗粒碰撞频率表达式,应用了颗粒数量平衡方程,从而建立了絮凝过程的动力学生长模型,模型计算结果与试验数据对比表明,二者趋势一致,在没有使用经验参数的情况下基本上能够描述黄河泥沙絮凝过程中絮体数量和尺寸分布的变化过程;对絮体结构的研究中,应用扫描电子显微镜和透射电子显微镜对絮体进行了观察,将絮体分为絮粒、絮团和絮网三个不同的生长阶段,通过假设颗粒结合位置符合正四面体,建立了絮体结构模型,计算得到的模型絮体分形维数基本与试验中的实际絮体相符,在一定程度上能眵反映高分子絮凝黄河泥沙生成的絮体结构。
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Its rule of change was obtained.On the basis of other studies,the flocculation kinetics and floes structure was studied. By making some assumptions, collision frequency were presented.Then the the flocculation kinetics model was established through population balance equation. Comparison of experimental data and modeling results indicate that there are the same trend between the two. So the model can predict floes number and size during flocculation of Yellow River's loess particles without using empirical parameters.The TEM and SEM were used to obsever floes in the study of floe structure.The flocculation was divided as flocculi,floc and floe aggregate.The floes structure model was established by assumption that particles position in floe accords with tetrahedron.The fractal dimension of model and experimental floes was found to be coincidentSo the model can reflect the structure of flocs formed in flocculation of Yellow River's loess particles by macromolecule flocculant at a certain extent
最后,本文还对絮凝动力学和絮体结构进行了研究,在前人研究的基础上,针对高分子絮凝黄河泥沙,对絮凝过程作了一些符合试验条件的假设,建立了颗粒碰撞频率表达式,应用了颗粒数量平衡方程,从而建立了絮凝过程的动力学生长模型,模型计算结果与试验数据对比表明,二者趋势一致,在没有使用经验参数的情况下基本上能够描述黄河泥沙絮凝过程中絮体数量和尺寸分布的变化过程;对絮体结构的研究中,应用扫描电子显微镜和透射电子显微镜对絮体进行了观察,将絮体分为絮粒、絮团和絮网三个不同的生长阶段,通过假设颗粒结合位置符西安建筑科技大学博士学位论文合正四面体,建立了絮体结构模型,计算得到的模型絮体分形维数基本与试验中的实际絮体相符,在一定程度上能够反映高分子絮凝黄河泥沙生成的絮体结构。
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The characteristics in design of components of tires, fundamental parameters and supplementary parameters for design of tire structure are analyzed. Then according to practical requirements and experience in design, general principles for tire design are put forward. The problems of disaccord of circle's radiuses in vertical and horizontal axis and the excessive errors in solving equations are solved. At last, with the work accomplished above, computer design of tire cross section may be achieved after completing those computer programs for the design.
论文首先分析了轮胎各部分的设计特点以及轮胎结构设计的基本参数和附加参数,根据实际要求和设计经验,提出了进行轮胎结构设计的总原则,解决了程序语言中圆的纵横比不统一和求解方程时误差太大的问题等,编制出了用于轮胎结构设计的子程序和总程序,实现了轮胎断面结构的计算机设计。
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It is then proved that every equation in the hierarchy possesses the Hamiltonian structure if L has a skew-symmetric factorization and the first equation in the hierarchy satisfies some simple condition (K〓=θf〓 and f〓 is a gradient function).
然后在L具有反对称分解L=θJ,及等谱发展方程族中第一个方程满足简单条件(K〓=θf〓,f〓一个梯度函数)的假设下,获得了整个方程族的Hamilton结构。
- 推荐网络例句
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Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).
呼气,收缩臀部肌肉;拱起身体,尽量抬起头来,右腿伸直朝向天花板(膝微屈,以避免肌肉紧张)。
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The cost of moving grain food products was unchanged from May, but year over year are up 8%.
粮食产品的运输费用与5月份相比没有变化,但却比去年同期高8%。
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However, to get a true quote, you will need to provide detailed personal and financial information.
然而,要让一个真正的引用,你需要提供详细的个人和财务信息。