查询词典 parameter curve

In this paper, taking one 1900t/h supercritical pressure once—through boiler installed in East boiler company as subject investigated, analyzing the structure and characteristic of unit, from the mechanism of units, based on the law of quality conservation, energy conservation and momentum conservation, having Lagrange fluid particle tracing idea in hydrodynamics field application in analyzing of unit operational characteristic, author build up the nonlinear distributed parameter general dynamic mathematical model of single-phase heating surface or diphase heating surface in the steam-water system for supercritical pressure once—through boiler, which is suitable numerical calculation and simulation for large scale disturbance and full working conditions change, and enough materializing distributed characteristic of thermodynamic parameter in process and time lag characteristic of energy transportation in tache. The transient responses curve of the system main variables under several disturbance are computed by Computer Simulation for the model, and theoretical analysis shows that the simulation results are reasonable.

本文以东方锅炉集团公司的一台1900 t /h超临界压力直流锅炉为研究对象，在分析机组结构和特性的基础上，从机组的工作机理出发，以质量、能量、动量守恒定律为依据，将流体力学领域中的Lagrange流体质点追踪思想用于机组运行特性的分析上，建立了适用于超临界压力直流锅炉汽水系统单相、双相受热面的非线性分布参数通用动态数学模型，该模型适合于大扰动全工况变化的数值仿真计算，充分体现了过程热力参数的分布特性和环节中能量输送过程的时滞特性，并对模型通过计算机仿真得出各种扰动下系统主要变量的响应曲线，从理论上分析了仿真结果的合理性。

In conventional indirected parameter estimate, such as Weighted Least Square Method, the changing activity of the injected radiotracer is conventionally measured through multiple consecutive PET image reconstructions. The image of the radioactivity distribution in each frame is reconstructed independently and the whole set of frames is then used to estimate the distribution of the physiological parameter of interest by the application of an appropriate pharmacokinetic model to the time radioactivity curve either of appropriately selected functional regions or of each image element.

传统的间接参数估计方法如加权最小二乘参数估计方法(Weighted Least SquareMethod，WLS)，需要首先从测量数据重建出PET动态放射性活度图像，然后在这些时间上连续的重建图像应用适当的动力学模型上估计感兴趣的生理参数，然而PET重建图像中往往含有极大的噪声，这些噪声将影响参数估计的准确性。

The method of prediction on stochastical simulating 3D parameter field of rock mechanics is brought forward in this paper. Namely, rock mechanics parameters- curve obtained by known and limited conventional log materials is took as inputs of hard data;and seismic attribute data body, hydrating of mud shale and rock environmental parameters data is took as constraint of soft data. By simulating stochastically through optimizing algorithm of Sequential Gauss Simulation,dynamical data field of rock mechanics parameter of three-dimensional space are gotten, then log response of rock mechanics parameters in position of any point in space is predicted.

提出三维岩石力学参数场随机模拟预测的方法，即以已知有限的常规测井资料计算出来的岩石力学参数曲线作为硬数据输入，以已知地震属性数据体及泥页岩水化和岩石环境参数数据作为软数据约束，选择序贯高斯模拟方法，随机模拟得到动态规律变化的岩石力学参数的三维空间数据场，然后由岩石力学参数的三维空间数据场预测空间任一位置的岩石力学参数在井上的测井响应，并把该反映动态规律变化的测井响应按照油田勘探开发的要求输出成特定格式，供生产和工程上使用。

Assuming a condition cont-rol reserve calculation,combimatively solve the material balance equation of gas recovery and binomial gas recovery equation for gas well,calculate the production curve of gas well and match it with the actual production curve,finally determine the reserve and productivity parameter,this method doesn't need much pressure build-up data,and can calculate the c...

该方法的推导思路是：假设在某一控制储量条件下，联立求解气藏物质平衡方程式和气井二项式采气方程，计算气井采气曲线并将其与实际的采气曲线相匹配，最后确定储量、产能参数。该方法不需要较长的多次关井复压资料，在气藏受水驱影响较小时，还可计算一口探井或气藏试采早期所反映出的气井控制储量，在气藏生产中得到应用，计算结果较为可靠

In accordance with two independent rectangular coordinate systems, this paper discusses the complete coordinate formula of the middle spiral curve, the two groups' basic relation which is different to the general one and the significant intentions for averting chain breaking, which comes from the line parameter selected to compute the right coordinate of the curve points.

从二个独立的直角坐标系出发，分析中插缓和曲线点位坐标计算的完整模式，说明中插缓和曲线有别于一般缓和曲线的两种基本关系，指出有效选用连接参数m值在准确计算中插缓和曲线完整点位坐标避免曲线断链的重要作用，结合实例阐述任意测站坐标变换技术计算中插缓和曲线点位坐标的公式和应用效果

Ythagorean hodograph curves enjoy a number of remarkable properties, such as, its offset curves have exact rational representations; the arc length function of a Pythagorean hodograph curve is simply a polynomial function of the curve parameter; and the lower degree Pythagorean hodograph curves have intuitive geometrical interpretation.

H曲线具有诸如有精确的有理 Offset、弧长函数可由多项式函数表示以及几何解释优美等一系列优良性质。基于复分析方法，避免了实分析讨论中出现的复杂表示及繁琐计算，构造了满足给定 C1 Hermite插值条件且以C1拼接连续的三次 PH曲线偶。该曲线偶可灵活处理拐点，从而克服了一般三次 PH曲线因恒凸而无法处理拐点的缺陷。

For the application of Mathematica in the differential geometry,this paper introduces how to processe the curve curvature and the torsion questions,the graphic expression of the curvature and the torsions,and draw curves by the curvature and the torsions. Curvature ; torsion ; solution curve ; osculating plane ; natural parameter ; natural equation

利用Mathematica，只要输入有关系统命令就可以得到期望的结果。1曲率和挠率及其图形意义假设R3上的曲线一般参数表示为r=r它的曲率和挠率计算公式是：κ=‖r′×r"‖‖r′‖3τ=‖r′×r‖我们知道，空间曲线r=r在一点(s=s0)邻近的近似方程为ξ=sη=120κs2ζ=160κ0τs3通过近似方程可以确定曲线在其基本三棱形的三个平面(即密切平面，法平面，从切平面)上的投

Based on the arc length formulae of the parallel to the easement curve and its property, this paper gives the parameter equations of the parallel to the easement curve taking the arc length itself as variable.

基于缓和曲线平行线弧长公式及其性质，给出了缓和曲线平行线以其自身弧长为变量的参数方程。

The paper discussed the main factors of influencing transition curve,introduced the choice and application of transition curve parameter and length.

阐述了决定缓和曲线的主要因素，指出了缓和曲线的选取和实际应用。

Bézier curve ; shape parameter ; curve design

Bézier曲线；形状参数；曲线设计

He could even think coolly of the dead man he had left in the house.

当他想起他留在房子里的那具死尸，他居然很镇静。

Based on the system of Na2O-Al2O3-SiO2 and both the crystal nucleus agent and complex fining agent,nepheline glass-ceramics in prepared though high temperature meltiong and two steps of heat treatment,and it possesses high compressive strength and high bending resistance.

本文以Na2O－Al2O3－SiO2系统为基础，引入晶核剂和复合澄清剂，经高温熔制和两步热处理制备的霞石微晶玻璃，具有较高的抗压和抗折强度。