使用双线近似的时间变化的弹性曲线来单次估计末缩弹性
T Shishido1, K Hayashi, K Shigemi
1Department of Cardiovascular Dynamics, National Cardiovascular Center Research Institute, Osaka, Japan. tosjoe@res.ncvc.go.jp
Circulation
|October 18, 2000
概括
一种新方法估计左心室末缩弹性 (Ees) 使用单击,克服临床限制. 这种方法通过随时可用的数据简化了收缩性评估.
科学领域:
- 心血管生理学心血管生理学
- 心脏机械学 心脏机械学
- 生物医学工程 生物医学工程
背景情况:
- 左心室末缩弹性 (Ees) 是一个关键的收缩率指数.
- 由于测量难度和负载条件的变化,Ees的临床应用受到限制.
研究的目的:
- 开发一种简化,单击的方法来估计Ees.
- 为了克服与传统Ees测量相关的技术挑战.
主要方法:
- 通过使用两个线性函数 (同体体缩和弹射相) 估计了时间变化的弹性曲线.
- 估计Ees在单击基础上使用压力值,缩时间间隔和中风体积.
- 验证了对麻醉狗的卡瓦尔闭塞的方法.
主要成果:
- 单击Ees估计方法显示了合理的准确性 (r=0.929).
- 尽管收缩率和加载条件发生了重大变化,但该方法仍然准确.
- 斜率因收缩率和负载变化而改变,但Ees的估计是稳定的.
结论:
- 可以在单击基础上可靠地估计Ees.
- 对时间变化的弹性曲线的双线函数近似使得准确的Ees计算成为可能.
- 这种方法简化了Ees评估,使用易于获得的变量.
相关概念视频
Flexural Stress
906
When analyzing bending in symmetric members, it's crucial to understand how stresses distribute when subjected to bending moments. This stress distribution is effectively described by applying fundamental mechanics and material science principles, particularly Hooke's Law for elastic materials.
Hooke's Law states that within the material's elastic limits, stress is directly proportional to strain. In a member experiencing a bending moment, the strain at any point is relative to its distance...
Hooke's Law states that within the material's elastic limits, stress is directly proportional to strain. In a member experiencing a bending moment, the strain at any point is relative to its distance...
906
Residual Stresses in Bending
688
In the study of elastoplastic members subjected to bending moments, understanding the loading and unloading phases is crucial for assessing material behavior and structural integrity. During the loading phase, as the bending moment increases, the material initially responds elastically, adhering to Hooke's Law, where stress is directly proportional to strain. When the load exceeds the yield strength, plastic deformation occurs, resulting in permanent strain and deformation that remains even...
688
Elastic Curve from the Load Distribution
588
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. Initially, this...
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. Initially, this...
588
Elastic Strain Energy for Shearing Stresses
668
As discussed in previous lessons, strain energy in a material is the energy stored when it is elastically deformed, a concept crucial in materials science and mechanical engineering. This energy results from the internal work done against the cohesive forces within the material. When a material undergoes shearing stress and corresponding shearing strain, the strain energy density, which is the energy stored per unit volume, is calculated. Within the elastic limit, where the stress is...
668
Linear Approximation in Time Domain
460
Nonlinear systems often require sophisticated approaches for accurate modeling and analysis, with state-space representation being particularly effective. This method is especially useful for systems where variables and parameters vary with time or operating conditions, such as in a simple pendulum or a translational mechanical system with nonlinear springs.
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
460
Elasticity in Concrete
535
Upon subjecting concrete to moderate or high uniaxial compressive or tensile stresses, the strain response is non-linear relative to the stress applied. As the stress is removed, the resulting stress-strain curve deviates from the original path traced during loading, creating a hysteresis loop, indicative of the concrete's non-linear and non-elastic properties. Typically, a material's modulus of elasticity, which is a measure of the material's stiffness, is inferred from the linear...
535


