大气循环的超稳定性和远程连接通过隐藏的马尔科夫模型和网络模块化
Dmitry Mukhin1, Roman Samoilov2, Abdel Hannachi3
1Institute of Applied Physics of RAS, Nizhny Novgorod, 603950, Russia. mukhin@ipfran.ru.
Scientific reports
|September 30, 2025
概括
科学家们使用隐藏的马尔科夫模型开发了一种新方法来识别被称为天气模式的大气循环模式. 这一进步提高了对气候变化和长期天气预报的理解.
科学领域:
- 大气动力学和气候科学.
- 非线性和混乱系统分析.
- 气象学中的统计建模.
背景情况:
- 低频大气变化是复杂的,难以预测.
- 天气模式是重复的,长期存在的循环模式,对预测至关重要.
- 超稳定性为理解政权形成提供了一个框架.
研究的目的:
- 开发一种有效的方法来识别大气循环模式.
- 将政权解释为一种超稳定状态的群体.
- 为了提高对大气可预测性的理解.
主要方法:
- 使用隐藏的马尔科夫模型 (HMM) 构建了一个系统演化运算符.
- 应用图形理论将HMM过渡矩阵划分为状态社区.
- 使用非线性内核主要组件映射用于HMM状态空间嵌入.
主要成果:
- 在北半球冬季确定了四种持续和反复的循环模式.
- 描述了这些制度的统计和动态特性及其表面影响.
- 发现与厄尔尼诺南方振荡和太平洋十年振荡的显著相关性,提前一年.
结论:
- 隐藏的马尔科夫模型方法可以有效地识别天气模式.
- 系统识别促进了对大气可预测性和远程连接的理解.
- 该方法揭示了循环模式和主要气候振荡之间的强烈联系.
相关概念视频
BIBO stability of continuous and discrete -time systems
887
System stability is a fundamental concept in signal processing, often assessed using convolution. For a system to be considered bounded-input bounded-output (BIBO) stable, any bounded input signal must produce a bounded output signal. A bounded input signal is one where the modulus does not exceed a certain constant at any point in time.
To determine the BIBO stability, the convolution integral is utilized when a bounded continuous-time input is applied to a Linear Time-Invariant (LTI) system....
To determine the BIBO stability, the convolution integral is utilized when a bounded continuous-time input is applied to a Linear Time-Invariant (LTI) system....
887
Multimachine Stability
545
Multimachine stability analysis is crucial for understanding the dynamics and stability of power systems with multiple synchronous machines. The objective is to solve the swing equations for a network of M machines connected to an N-bus power system.
In analyzing the system, the nodal equations represent the relationship between bus voltages, machine voltages, and machine currents. The nodal equation is given by:
In analyzing the system, the nodal equations represent the relationship between bus voltages, machine voltages, and machine currents. The nodal equation is given by:
545
Entropy Change in Reversible Processes
3.2K
In the Carnot engine, which achieves the maximum efficiency between two reservoirs of fixed temperatures, the total change in entropy is zero. The observation can be generalized by considering any reversible cyclic process consisting of many Carnot cycles. Thus, it can be stated that the total entropy change of any ideal reversible cycle is zero.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
3.2K
Propagation of Uncertainty from Systematic Error
1.4K
The atomic mass of an element varies due to the relative ratio of its isotopes. A sample's relative proportion of oxygen isotopes influences its average atomic mass. For instance, if we were to measure the atomic mass of oxygen from a sample, the mass would be a weighted average of the isotopic masses of oxygen in that sample. Since a single sample is not likely to perfectly reflect the true atomic mass of oxygen for all the molecules of oxygen on Earth, the mass we obtain from this...
1.4K
State Space Representation
531
The frequency-domain technique, commonly used in analyzing and designing feedback control systems, is effective for linear, time-invariant systems. However, it falls short when dealing with nonlinear, time-varying, and multiple-input multiple-output systems. The time-domain or state-space approach addresses these limitations by utilizing state variables to construct simultaneous, first-order differential equations, known as state equations, for an nth-order system.
Consider an RLC circuit, a...
Consider an RLC circuit, a...
531
Multi-input and Multi-variable systems
392
Cruise control systems in cars are designed as multi-input systems to maintain a driver's desired speed while compensating for external disturbances such as changes in terrain. The block diagram for a cruise control system typically includes two main inputs: the desired speed set by the driver and any external disturbances, such as the incline of the road. By adjusting the engine throttle, the system maintains the vehicle's speed as close to the desired value as possible.
In the absence of...
In the absence of...
392


