The Importance of the Shape Parameter in a Bulk Parameterization Scheme to the Evolution of the Cloud Droplet Spectrum during Condensation

The shape parameter of the Gamma size distribution plays a key role in the evolution of the cloud droplet spectrum in the bulk parameterization schemes. However, due to the inaccurate specification of the shape parameter in the commonly used bulk double-moment schemes, the cloud droplet spectra cannot reasonably be described during the condensation process. Therefore, a newly-developed triple-parameter condensation scheme with the shape parameter diagnosed through the number concentration, cloud water content, and reflectivity factor of cloud droplets can be applied to improve the evolution of the cloud droplet spectrum. The simulation with the new parameterization scheme was compared to those with a high-resolution Lagrangian bin scheme, the double-moment schemes in a parcel model, and the observation in a 1.5D Eulerian model that consists of two cylinders. The new scheme with the shape parameter varying with time and space can accurately simulate the evolution of the cloud droplet spectrum. Furthermore, the volume-mean radius and cloud water content simulated with the new scheme match the Lagrangian analytical solutions well, and the errors are steady, within approximately 0.2%.

New cubic rational basis with tension shape parameters

By using the blossom approach, we construct four new cubic rational Bernsteinlike basis functions with two shape parameters, which form a normalized B-basis and include the cubic Bernstein basis and the cubic Said-Ball basis as special cases. Based on the new basis, we propose a class of C2 continuous cubic rational B-spline-like basis functions with two local shape parameters, which includes the cubic non-uniform B-spline basis as a special case.Their totally positive property is proved. In addition, we extend the cubic rational Bernsteinlike basis to a triangular domain which has three shape parameters and includes the cubic triangular Bernstein-B′ezier basis and the cubic triangular Said-Ball basis as special cases. The G1 continuous conditions are deduced for the joining of two patches. The shape parameters in the bases serve as tension parameters and play a foreseeable adjusting role on generating curves and patches.

Circular object recognition based on shape parameters

To recognize circular objects rapidly in satellite remote sensing imagery, an approach using their geometry properties is presented. The original image is segmented to be a binary one by one dimension maximum entropy threshold algorithm and the binary image is labeled with an algorithm based on recursion technique. Then, shape parameters of all labeled regions are calculated and those regions with shape parameters satisfying certain conditions are recognized as circular objects. The algorithm is described in detail, and comparison experiments with the randomized Hough transformation （RHT） are also provided. The experimental results on synthetic images and real images show that the proposed method has the merits of fast recognition rate, high recognition efficiency and the ability of anti-noise and anti-jamming. In addition, the method performs well when some circular objects are little deformed and partly misshapen.

Subtle Influence of the Weibull Shape Parameter on Homer Optimization Space of a Wind Diesel Hybrid Gen Set for Use in Southern Brazil

Wind power is an increasingly important alternative for obtaining energy supplies, both in large interconnected power systems and in smaller hybrid systems and even in backup systems. The temporal and spatial variability of the winds represent an obstacle to be overcome so that wind energy can be increasingly used. The capacity factor of wind farms shows how this variability impacts the operation of the plants and its value is of the order of 30% to 35%. The variability of the wind speed is influenced if the point of interest is on land or on sea, the shape of the surface, the proximity of water bodies, among other factors. The availability of wind is best described by the Weibull probability distribution, which has as one of its defining parameters one which is termed as shape parameter. This parameter is much higher as higher is the variability of the wind speed. This paper studies the subtle influence of Weibull shape parameter on the optimal combination of components in a wind diesel hybrid system, by means of computer simulations with the well known software Homer. The results indicate a relatively small influence (as expected) in the studied system, which appears particularly when the cost of diesel is higher and the availability of wind is lower.

Generate mesh with shape parameters

In CAD/CAM, mesh rather than smooth surface is only needed sometimes. A mesh-generating method from permanence principle of Coons patch is developed. A new mesh point is defined through local small subpatch and all mesh points are computed by a linear system with special symmetric block tridiagonal coefficient matrix. By simplification, the determinant of coefficient matrix is determined by determinants of submatrices. Condition of existence of solution is given. Whether coefficient matrix is singular can be judged by a simple polynomial function with the eigenvalue of submatrix as variable. Numerical examples demonstrate the effects of shape parameters.

NEW TRIGONOMETRIC BASIS POSSESSING EXPONENTIAL SHAPE PARAMETERS

Four new trigonometric Bernstein-like basis functions with two exponential shape pa- rameters are constructed, based on which a class of trigonometric Bézier-like curves, anal- ogous to the cubic Bézier curves, is proposed. The corner cutting algorithm for computing the trigonometric Bézier-like curves is given. Any arc of an eliipse or a parabola can be represented exactly by using the trigonometric Bézier-like curves. The corresponding trigonometric Bernstein-like operator is presented and the spectral analysis shows that the trigonometric Bézier-like curves are closer to the given control polygon than the cu- bic Bézier curves. Based on the new proposed trigonometric Bernstein-like basis, a new class of trigonometric B-spline-like basis functions with two local exponential shape pa- rameters is constructed. The totally positive property of the trigonometric B-spline-like basis is proved. For different values of the shape parameters, the associated trigonometric B-spline-like curves can be C2 N FC3 continuous for a non-uniform knot vector, and C3 or C5 continuous for a uniform knot vector. A new class of trigonometric Bézier-like basis functions over triangular domain is also constructed. A de Casteljau-type algorithm for computing the associated trigonometric Bézier-like patch is developed. The conditions for G1 continuous joining two trigonometric Bézier-like patches over triangular domain arededuced．

A Class of Spline Curves with Four Local Shape Parameters

A class of spline curves with four local shape parameters, which includes the quartic spline curves with three local shape parameters given in Han [Xuli Han. A class of general quartic spline curves with shape parameters. Comput. Aided Geom. Design, 28：151-163 （2011）], is proposed. Without solving a linear system, the spline curves can be used to interpolate sets of points with C2 continuity partly or entirely. The shape parameters have a predictable adjusting role on the sp[ine curves.

MODIFIABLE QUARTIC AND QUINTIC CURVES WITH SHAPE-PARAMETERS

This paper presents a method for creating modificable quartic and quintic curves with shape parameters. The curves can achieve C 2 even C 3 continuity and unify both interpolation and approximation to the control points without solving a system of equations or inserting additional control points. They have the local properties like the cubic B spline. Besides, the quintic curve would be able globally to tend the control polygon.

A New Local Control Spline with Shape Parameters for CAD/CAM

A new local control spline based on shape parameters with G^2 continuity,called BLC-spline,is pro- posed.Not only is BLC-spline very smooth,but also the spline curve's characteristic polygon has only three control vertices,and the characteristic polyhedron has only nine control vertices.The behavior of lo- cal control of BLC-spline is better than that of the other splines such as cubic Bezier,B and Beta-spline.The three shape parameters β_0,β_1 and β_2 of BLC-spline,which are independent of the con- trol vertices,may be altered to change the shape of the curve or surface.It is shown that BLC-spline may be used to construct a space arc spline for DNC machining directly.That is a powerful tool for the design and manufacture of curves and surfaces in integrated CAD/CAM systems.

Research on shape parameters of circular arc disc teeth for three-cone bit

Through the single row drilling experiment,this paper studied the regularity of the tooth shape parameter's influence to the disc teeth's rock-breaking effect,which provided some basis for the composite teeth type roller bit's combined experimental study and the structure design of the tooth type.This experimental research is only for the circular arc disc teeth which is arranged on the composite teeth type roller bit's main tooth.The experiments were designed using the method of orthogonal design and the results were analyzed by the fuzzy optimization method.The results show that the disc tooth's drilling effect is the best when the tip diameter is 2 mm,taper angle is 30
and the groove number is 8,and the disc tooth's drilling effect is the second best when the tip diameter is 3 mm,taper angle is 30
and the groove number is 7.The above two combined ways of drilling effect's difference is very small(the difference of the degree of the membership is 0.003).

A Radial Basis Function Method with Improved Accuracy for Fourth Order Boundary Value Problems

Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with Radial Basis Function methods. The method is used to solve fourth order boundary value problems. The use and location of ghost points are examined in order to enforce the extra boundary conditions that are necessary to make a fourth-order problem well posed. The use of ghost points versus solving an overdetermined linear system via least squares is studied. For a general fourth-order boundary value problem, the recommended approach is to either use one of two novel sets of ghost centers introduced here or else to use a least squares approach. When using either ghost centers or least squares, the random variable shape parameter strategy results in significantly better accuracy than when a constant shape parameter is used.

Influence of the roughness and shape of quartz particles on their flotation kinetics

Surface roughness and shape play an important role on the behavior of particles in various processes such as flotation. In this re- search, the influence of different grinding methods on the surface roughness and shape characteristics of quartz particles as well as the effect of these parameters on the flotation of the particles was investigated. The surface roughness of the particles was determined by measuring their specific surface area via the gas adsorption method. The shape characteristics of the particles were measured and calculated by images obtained by scanning electron microscopy via an image analysis system. The flotation kinetics was determined using a laboratory flotation cell. The results showed that the particles of rod mill products have higher roughness and elongation ratio and lower roundness than the parti- cles of ball mill products. The flotation kinetics constant of the particles increased with their surface roughness increasing. Particles with higher elongation and lower roundness indicated higher floatability. In addition, the influence of the surface roughness on the flotation kinet- ics was greater than that of shape parameters.

东北女青年参数化鞋楦定制研究

本文基于东北女青年的脚型特征及规律,构建了一种特征点的参数化建模方法。采用三维足部扫描仪提取东北女青年18个足部特征参数,分析其脚型特征及规律,利用逆向工程技术确定286个特征点。根据脚楦关系,调整东北女青年鞋楦尺寸参数,以脚长和基宽为自变量,建立其与特征点长度方向、宽度方向、高度方向的参数关系,以构建东北女青年参数化鞋楦模型。采用该方法获得的鞋楦模型数字化程度高,便于鞋楦参数调整,对于个性化鞋楦定制具有重要意义。

Cognition,Application and Discussion on Shaped Charge Hydraulic Smooth Blasting Technology

In the past,the main method of tunnel excavation in China was drilling and blasting,but the biggest shortcoming of the traditional drilling and blasting method is that it is easy to cause serious overexcavation and underexcavation.At the same time,the operation cycle time of this method is long,which leads to a serious waste of resources.Not only that,a large number of toxic gases and dust produced after blasting also do harm to the health of construction workers.So this is an urgent need for a new construction technology to solve this worldwide problem.In this situation,the leading experts in the field of tunnel,"The survey and design master of China"Shi Yuxin,Liu Pei,and well-known expert in explosion field,yan-sheng ding,professor Chen Chengguang and Gu Yicheng,the experts group,cooperate with The Fifth Branch of China Railway 18th Bureau in northwest project management department,developed a new technology.This technology has passed the appraisal of scientific and technological achievements organized by Tianjin Science and Technology Commission,which is shaped hydraulic smooth blasting technology.The comprehensive evaluation of the technology is"international leading"level.This paper is mainly aimed at the drawbacks of drilling and blasting construction,combined with the author's cognition and discussion on the introduction of the new technology of cumulative hydraulic blasting and the practical application effect in the tunnel excavation process of the fourth company of China Railway 14th Bureau Group in the second division of the 9th bid section of Zhangjihuai Railway in Huainan Province.

Population structure of Araucaria angustifolia under distinct forest protection status:implications for management and conservation

Araucaria angustifolia is the dominant coniferous species in Brazil,a long-lived pioneer species and a supplier of valuable timber and non-timber products,which gives it key-species status.This study examines how A.angustifolia population structure affects the stand structure,and whether these relationships differ between protected and unprotected areas.The study was carried out on two protection status forests(national forest and urban forest)in a region of Atlantic mixed forest in ParanáState,southern Brazil.Skewness coefficient and the Weibull shape parameter described the population structure and its effects on species diversity and biomass stock.Population diameter distribution differed significantly between forests,with unbalanced structure in both,although regeneration was more abundant in the protected area.Skewness positively affected aboveground biomass whereas shape negatively affected it and species diversity.These relationships differed between protected and unprotected stands.The effect of A.angustifolia populations on stand structure was conditioned on protection status.Old-growth populations may have lower diversity and biomass stock even supporting large trees.Consequently,old-growth forests,can lead to wood loss through mortality,senescence,and declining populations,representing the waste of a valuable timber resource.These findings provide useful knowledge for forest management,species conservation,and the carbon market.

Local Radial Basis Function Methods: Comparison, Improvements, and Implementation

Radial Basis Function methods for scattered data interpolation and for the numerical solution of PDEs were originally implemented in a global manner. Subsequently, it was realized that the methods could be implemented more efficiently in a local manner and that the local approaches could match or even surpass the accuracy of the global implementations. In this work, three localization approaches are compared: a local RBF method, a partition of unity method, and a recently introduced modified partition of unity method. A simple shape parameter selection method is introduced and the application of artificial viscosity to stabilize each of the local methods when approximating time-dependent PDEs is reviewed. Additionally, a new type of quasi-random center is introduced which may be better choices than other quasi-random points that are commonly used with RBF methods. All the results within the manuscript are reproducible as they are included as examples in the freely available Python Radial Basis Function Toolbox.

杭州奥体中心体育游泳馆结构设计要点

杭州奥体中心体育游泳馆为2022年第19届杭州亚运会主场馆,亚运会期间作为篮球、游泳、跳水和花样游泳的比赛场馆。该场馆总建筑面积约39.7万m~2,东西向尺寸609m、南北向尺寸200m,包含一座18000座的体育馆和6000座的游泳馆,是世界上最大的两馆连接体非线性造型场馆。介绍了该场馆的概况、结构体系、设计要点等相关内容。着重阐述了结构设计中的一些关键问题及相应的处理措施,包括超长混凝土结构、体型系数、屋盖参数化、屋盖支承边界、异形跳台,稳定性分析等。

民机气源系统风扇进气入口气动外形设计方法

民用飞机气源系统风扇进气入口作为冷边引气的关键部件,其气动外形设计的优劣直接影响到发动引气系统的性能。总结了风扇进气入口的设计流程,采用参数化设计、三维流体力学仿真评估和风洞试验的步骤,实现了设计闭环。梳理了设计要求和设计点选取原则,确定了主要设计要素的理论计算方法,开发了一套参数化设计的程序,并通过仿真和试验的方法对设计结果进行了验证。对后续型号设计提供了指导和参考,提高了设计效率。

低碳导向下屋顶遮阳与异形外遮阳参数化整合设计——以西安某剧场项目为例

建筑采用屋顶遮阳与外遮阳整合设计对塑造建筑立面形象和营造舒适的室内热环境有着相互关联的影响。近些年,采用工具Ladybug+Honeybee进行参数化性能设计来配合建筑方案成为设计趋势。以该工具为基础的设计实践进行研究和分析,对西安某剧场项目的遮阳形式解读归纳,得出采用屋顶遮阳与立面构件遮阳相结合的遮阳措施,并调用Radiance+EnegyPlus软件模拟建筑表面的累积太阳辐射量、围护结构综合能耗、表皮温度和夏季室内温度,分析了该项目采用的遮阳通风层隔热、遮阳表皮的热缓冲效应对建筑表面太阳辐射量、综合能耗的影响比例。经计算,与无遮阳条件对比,该项目采用的综合遮阳方式使得太阳辐射降低60%,围护结构全年综合能耗降低9%,夏季室温更接近舒适室内温度的要求,为建筑遮阳技术应用与屋顶、立面一体化的方案设计提供了一定的思路和参数参考。

基于CST参数化的导弹三维几何建模方法

针对建模效率低、成本高的问题,本文在二维CST参数化方法的基础上,引入纵向轮廓描述函数,将原二维建模向三维建模扩展,建立能够准确描述导弹三维形状特征的解析函数。在此基础上,通过在VB环境中对CATIA进行二次开发,使其能够在CATIA中进行自动生成、修补和更新。几何模型可以被导出和保存,并作为多学科设计与分析的基础。结果表明,本文提出的三维CST建模技术可以满足复杂几何建模的要求,有效简化了导弹参数化过程。