一个结构优化算法,具有随机力和应力
1Department of Physics, College of William & Mary, Williamsburg, VA, USA. schen24@email.wm.edu.
Nature computational science
|January 4, 2024
概括
我们开发了一个新的优化算法,以有效地处理量子计算和结构优化中常见的噪音梯度. 这种方法提高了复杂的科学计算中的稳定性和性能.
科学领域:
- 计算物理 计算物理
- 材料科学 材料科学 材料科学
- 量子计算是一种量子计算.
背景情况:
- 结构优化通常涉及诸如蒙特卡洛采样或量子设备缺陷等方法的随机噪声.
- 现有的优化算法与这些计算中固有的噪音作斗争,限制了准确性和效率.
研究的目的:
- 为具有噪音梯度的系统开发一个强大而高效的优化算法.
- 为了证明该算法的有效性在初始多体计算和材料发现方面.
主要方法:
- 一个新的算法结合了最的下降更新规则与统计错误和步骤大小的分阶段调度.
- 位置平均化技术以减轻随机噪声的影响.
- 与既有和最先进的机器学习优化方法进行比较.
主要成果:
- 拟议的算法在现实的噪音条件下表现出一致的效率和稳定性.
- 在固体中使用ab initio多体计算 (辅助场量子蒙特卡洛) 成功应用到全度优化.
- 在中发现一种潜在的超稳定结构,使用密度函数计算与合成噪声力.
结论:
- 新的算法有效地解决了科学优化中随机噪声所带来的挑战.
- 它使准确和高效的大规模计算成为可能,进步了材料科学和量子计算等领域.
- 该方法有助于发现新的材料结构和特性.
相关概念视频
Stress: General Loading Conditions
313
To grasp the intricacy of real-world conditions where multiple loads are applied simultaneously to a structure, one might visualize a section passing through a specific point within a body, aligned parallel to the xy plane. This section is subjected to various forces, including original loads, normal forces, and shearing forces.
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes....
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes....
313
Transformation of Plane Stress
230
Studying stress transformation is essential in understanding how stress components within a material, like a cube under plane stress, change with rotation. This change is analyzed by considering a prismatic element within the cube. As the element rotates, the stress components acting on it—both normal and shearing stresses—change in magnitude and orientation. This change is quantified using trigonometric functions of the rotation angle, relating the forces acting on the rotated element's...
230
Stresses under Combined Loadings
155
When analyzing a bent tube with a circular cross-section subjected to multiple forces, it is crucial to determine the stress distribution in order to maintain structural integrity under varied load conditions.
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...
155
Applications of Stress
266
Consider a structure made of a boom and a rod designed to support a load. These two components are connected by a pin and stabilized by brackets and pins. The boom and the rod are detached from their supports to assess the different stresses imposed on this structure, and a free-body diagram is drawn. Then, all the forces applied, including the load acting on the structure, are identified. The reaction forces exerted on both the boom and the rod are computed using the equilibrium equations.
The...
The...
266
General State of Stress
186
The general state of stress within a material can be accurately depicted using a stress tensor. This tensor encapsulates the internal forces distributed within a material subjected to external forces or deformations.
Specifically, consider a tetrahedral element where one face, labeled XYZ, is perpendicular to the line OA, and the remaining faces align with the coordinate axes with point O as the origin. At any point, such as point O, the stress tensor can be used to determine the stress...
Specifically, consider a tetrahedral element where one face, labeled XYZ, is perpendicular to the line OA, and the remaining faces align with the coordinate axes with point O as the origin. At any point, such as point O, the stress tensor can be used to determine the stress...
186
Components of Stress
217
Stress analysis under multiple loading conditions is intricate, necessitating a comprehensive grasp of normal and shearing stresses. Consider a small cube at point O, subjected to stress on all six faces, visible or not. Normal stress components σx, σy, σz act perpendicularly to the x, y, and z axes. Shearing stress components τxy and τxz are exerted on faces perpendicular to these axes.
Interestingly, the hidden cube faces also experience these stresses, equal and...
Interestingly, the hidden cube faces also experience these stresses, equal and...
217


