用非线性相对曲率测量方法比较卵形方程
Meng Lian1, Ke He2, David A Ratkowsky3
1Department of Applied Mathematics, College of Science, Nanjing Forestry University, Nanjing 210037, China.
Poultry science
|July 27, 2024
概括
普雷斯顿方程 (PE) 最好描述鸟蛋的几何形状,并计算体积/表面积. 这项研究有助于根据其形状特征对家禽蛋进行分类.
科学领域:
- 鸟类学 鸟类学是一门学科.
- 生物物理学的生物物理.
- 数学生物学 数学生物学
背景情况:
- 蛋的形状对于鸟类的生态和进化至关重要.
- 2D蛋形方程可以将3D蛋形几何模型作为革命的固体.
- 准确的卵体积和表面积计算对于家禽分类很重要.
研究的目的:
- 为了比较四个2D蛋形方程在描述鸟蛋几何学中的准确性.
- 评估计算蛋体积和表面积的最佳方程.
- 探索卵形参数在了解鸟类生态和进化中的潜力.
主要方法:
- 将普雷斯顿方程 (PE) 和特罗西安科方程 (TE) 与其他两个方程进行比较,使用350个鸟蛋样本.
- 使用调整的平方根平均值误差量化预测错误.
- 使用相对曲率测量来评估非线性.
- 经过验证的体积和表面积预测与经验测量对比.
主要成果:
- 在测试的方程中,PE表现出最低的预测误差和最小的非线性.
- 这四个方程都为计算蛋体积和表面积提供了有效的,可比的结果.
- 拟议的5参数TE在Gallus gallus domesticus中表现出色,但不如PE那么普遍.
结论:
- 普雷斯顿方程是描述鸟蛋几何和计算体积/表面积的最有效方法.
- 准确的几何建模辅助基于形态特征的家禽蛋分类.
- 蛋形分析为鸟类生态和进化模式提供了洞察力.
相关概念视频
Bending of Curved Members - Strain Analysis
131
The mechanics of deformation in curved members, such as beams or arches, under bending moments, involve complex responses. When such a member, symmetric about the y-axis and shaped like a segment of a circle centered at point C, is subjected to equal and opposite forces, its curvature and surface lengths change significantly. This alteration results in the shift of the curvature's center from C to C', indicating a tighter curve.
The important part of bending analysis for such a member...
The important part of bending analysis for such a member...
131
Equation of the Elastic Curve
482
The concept of curvature in plane curves, crucial in structural engineering, defines how sharply a beam bends under load. This curvature is determined using the curve's first and second derivatives.
Consider a cantilever beam with a point load at its free end (for instance, a diving board). When analyzing beam deflection with small slopes, the shape of the beam's elastic curve becomes key. The governing equation for this analysis involves the bending moment and the beam's flexural...
Consider a cantilever beam with a point load at its free end (for instance, a diving board). When analyzing beam deflection with small slopes, the shape of the beam's elastic curve becomes key. The governing equation for this analysis involves the bending moment and the beam's flexural...
482
Bending of Curved Members - Neutral Surface
178
In curved beams, unlike straight beams, the stress distribution across the cross-section is not uniform due to the beam's curvature. This non-uniformity arises because the neutral axis, where stress is zero, does not align with the centroid of the section. In a curved beam, the strain varies along the section as a function of the distance from the neutral axis.
Consider the curved member described in the previous lesson. According to Hooke's law, which relates stress to strain within...
Consider the curved member described in the previous lesson. According to Hooke's law, which relates stress to strain within...
178
Elastic Curve from the Load Distribution
170
The structural behavior of beams under distributed loads is critical for engineering analysis, which focuses on predicting how beams bend and react under such conditions. Different types of beams (e.g., cantilever, supported, or overhanging) behave differently under distributed load conditions.
For all beams, the analysis of the beam's reaction to distributed loads begins by understanding the relationship between a beam's load and the resulting shear forces and bending moments.
For all beams, the analysis of the beam's reaction to distributed loads begins by understanding the relationship between a beam's load and the resulting shear forces and bending moments.
170
Deformations in a Symmetric Member in Bending
165
When analyzing the deformation of a symmetric prismatic member subjected to bending by equal and opposite couples, it becomes clear that as the member bends, the originally straight lines on its wider faces curve into circular arcs, with a constant radius centered at a point known as Point C. This phenomenon helps to understand the stress and strain distribution within the member more clearly.
When the member is segmented into tiny cubic elements, it is observed that the primary stress...
When the member is segmented into tiny cubic elements, it is observed that the primary stress...
165
Curve Equations
28
Curves are essential geometric elements characterized by tangent distance, chord length, middle ordinate, and total arc length. These measurements are crucial in understanding a curve's geometric and spatial properties and are defined by the relationship between its radius and its central angle.The tangent distance (T) refers to the straight-line measurement from the intersection point of two tangents to either the start or end of the curve. This distance is influenced by the curve's radius (R)...
28


