Uncertainty Estimation Method for Windspeed Random Fluctuation Based on it’s Amplitude Modulation Effect

At present, with the development of wind’s energy application and disaster prevention, the windspeed uncertainty must be estimated because of the existing large gap between the requirement of prediction performance and current techniques owing to it’s strong random fluctuation. In this paper, a new method for windspeed uncertainty estimation is proposed on the base of physical mechanism, the inherent amplitude modulation effect in windspeed. According to the the atmosphere motion power spectrum in low-layers, the actual windspeed is usually decomposed into the hourly average windspeed and the turbulent residual error by many researchers. And the turbulent residual error and the turbulent standard deviation is modulated by the hourly average windspeed. Moreover experiments further show that the confidence interval of windspeed random fluctuation uncertainty based on it’s amplitude modulation effect is more rigorous than that obtained by general statistical model. As a result, this uncertainty estimation method has certain physical academic meaning and engineering application value both in the electric system and the other wind domain.

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Multi-Scale Amplitude Modulation Effect of Wind Speed Random Fluctuation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.851.396 ◽

2016 ◽

Vol 851 ◽

pp. 396-401

Author(s):

Jie Wan ◽

Guo Rui Ren ◽

Wen Bo Hao ◽

Jin Fu Liu ◽

Da Ren Yu ◽

...

Keyword(s):

Wind Speed ◽

Wind Power ◽

Amplitude Modulation ◽

Large Scale ◽

Engineering Application ◽

Random Fluctuation ◽

Modulation Effect ◽

Wind Power Integration ◽

Multi Scale ◽

Scale Characteristics

Wind power is widely used as a type of clean and renewable energy source in recent years. However, large-scale wind power penetration brings lots of challenges due to the uncertainty of wind speed. As a result, the research of wind speed uncertainty plays an important role in large scale wind power integration. In this paper, the multi-scale amplitude modulation effect of wind speed random fluctuation is found based on actual wind speed data. And the physical mechanism of multi-scale characteristics are presented from the perspective of turbulence. This research has both certain physical academic meaning and engineering application value in wind speed uncertainty research.

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The Iterative Method for Reliability Estimation of Fatigue Life

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.249-250.628 ◽

2012 ◽

Vol 249-250 ◽

pp. 628-631

Author(s):

Xin Li Bai ◽

Peng Xu ◽

Jiang Yan Li

Keyword(s):

Fatigue Life ◽

Design Method ◽

Estimation Method ◽

Engineering Application ◽

Reliability Estimation ◽

Fatigue Reliability ◽

Reliability Design ◽

Fatigue Design ◽

Machine Parts ◽

Stress Cycles

The expression of reliability estimation method for fatigue life of machine parts was derived, and two kinds of stress cycles (reversed cycle and un-symmetric reversed cycle) were considered. An iteration method is presented and the corresponding computer program named STRENGTH-2 is developed for estimating reliable life of machine parts. The engineering application results show that the calculated results are close to experimental results. The proposed method can be convenient to carry out the fatigue reliability design for machine parts under the action of uni-axial and multi-axial loadings, and promote the popularization and application of existing anti-fatigue design method. It has the high value of engineering application.

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Remaining Useful Life Prediction of Lithium-Ion Batteries Based on Wiener Processes with Considering the Relaxation Effect

Energies ◽

10.3390/en12091685 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1685 ◽

Cited By ~ 12

Author(s):

Xiaodong Xu ◽

Chuanqiang Yu ◽

Shengjin Tang ◽

Xiaoyan Sun ◽

Xiaosheng Si ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Estimation Method ◽

Engineering Application ◽

Prediction Method ◽

Lithium Ion ◽

Relaxation Effect ◽

Remaining Useful Life ◽

Parameters Estimation ◽

Wiener Processes ◽

Useful Life

Remaining useful life (RUL) prediction has great importance in prognostics and health management (PHM). Relaxation effect refers to the capacity regeneration phenomenon of lithium-ion batteries during a long rest time, which can lead to a regenerated useful time (RUT). This paper mainly studies the influence of the relaxation effect on the degradation law of lithium-ion batteries, and proposes a novel RUL prediction method based on Wiener processes. This method can simplify the modeling complexity by using the RUT to model the recovery process. First, the life cycle of a lithium-ion battery is divided into the degradation processes that eliminate the relaxation effect and the recovery processes caused by relaxation effect. Next, the degradation model, after eliminating the relaxation effect, is established based on linear Wiener processes, and the model for RUT is established by using normal distribution. Then, the prior parameters estimation method based on maximum likelihood estimation and online updating method under the Bayesian framework are proposed. Finally, the experiments are carried out according to the degradation data of lithium-ion batteries published by NASA. The results show that the method proposed in this paper can effectively improve the accuracy of RUL prediction and has a strong engineering application value.

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Influence of likelihood function choice for estimating crop model parameters using the generalized likelihood uncertainty estimation method

Agricultural Systems ◽

10.1016/j.agsy.2010.01.006 ◽

2010 ◽

Vol 103 (5) ◽

pp. 256-264 ◽

Cited By ~ 103

Author(s):

Jianqiang He ◽

James W. Jones ◽

Wendy D. Graham ◽

Michael D. Dukes

Keyword(s):

Likelihood Function ◽

Estimation Method ◽

Crop Model ◽

Uncertainty Estimation ◽

Model Parameters ◽

Generalized Likelihood Uncertainty Estimation

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Uncertainty Estimation in Intelligent Coordinate and Profile Measurement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.564 ◽

2010 ◽

Vol 447-448 ◽

pp. 564-568

Author(s):

Kiyoshi Takamasu ◽

Satoru Takahashi ◽

Xin Chen

Keyword(s):

Uncertainty Propagation ◽

Estimation Method ◽

Uncertainty Estimation ◽

Experimental Results ◽

Profile Measurement ◽

Simulation Results

The uncertainty estimation of coordinate and profile measurement is essential for accurate measurement and establishment of traceability. We proposed an uncertainty propagation method to estimate the uncertainty of coordinate and profile measurement. In this article, the multi sensor algorithm with uncertainty estimation method is described for the profile measurement. Additionally, two examples of multi sensor method are introduced. According to the simulation results of assessing uncertainty and the experimental results, the validity of the method was confirmed.

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Research of Gear Shift Control Technology for a New 8-Step Speed Automatic Transmission

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.455.376 ◽

2013 ◽

Vol 455 ◽

pp. 376-382 ◽

Cited By ~ 2

Author(s):

Yang Liu ◽

Shu Han Wang ◽

Xi Lu ◽

Ting Bin Song ◽

Wen Shu Wei ◽

...

Keyword(s):

Control Algorithm ◽

Automatic Transmission ◽

Estimation Method ◽

Engineering Application ◽

Shift Control ◽

Torque Estimation ◽

Set Up ◽

Control Principle ◽

Shift Clutch ◽

The Ideal

For the development research for a new 8 step speed automatic transmission, a simplified dynamic model for this transmission was established. Aimed at four basic shift types, the ideal characteristics of shift clutch and engine control were set up. By using torque estimation method, PI slip control algorithm and engine coordinated control principle, the control model were developed for two main shift phases which are torque phase and inertia phase. The test on the rig and vehicle verified the accuracy and feasibility of this shift control strategy. The development model and algorithm have a high value for engineering application.

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A Novel Eye-Diagram Estimation Method for Pulse Amplitude Modulation With N-Level (PAM-N) on Stacked Through-Silicon Vias

IEEE Transactions on Electromagnetic Compatibility ◽

10.1109/temc.2018.2843813 ◽

2019 ◽

Vol 61 (4) ◽

pp. 1198-1206 ◽

Cited By ~ 2

Author(s):

Junyong Park ◽

Daniel H. Jung ◽

Byunggon Kim ◽

Sumin Choi ◽

Youngwoo Kim ◽

...

Keyword(s):

Amplitude Modulation ◽

Estimation Method ◽

Pulse Amplitude ◽

Pulse Amplitude Modulation ◽

Through Silicon Vias ◽

Eye Diagram ◽

N Level ◽

Silicon Vias

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Technical note: Uncertainty in multi-source partitioning using large tracer data sets

10.5194/hess-2019-197 ◽

2019 ◽

Cited By ~ 1

Author(s):

Alicia Correa ◽

Diego Ochoa-Tocachi ◽

Christian Birkel

Keyword(s):

Estimation Method ◽

High Elevation ◽

Uncertainty Estimation ◽

Technical Note ◽

Data Sets ◽

Balance Equations ◽

Bayesian Approaches ◽

Taylor Series Approximation ◽

Source Contributions ◽

Source Partitioning

Abstract. The availability of large tracer data sets opened up the opportunity to investigate multiple source contributions to a mixture. However, the source contributions may be uncertain and apart from Bayesian approaches to estimate such source uncertainty only sound methods for two and three sources. We expand these methods developing an uncertainty estimation method for four sources based on multiple tracers as input data. Taylor series approximation is used to solve the set of linear mass balance equations. We illustrate the method with an example from hydrology, where we use a large tracer set from four water sources contributing to streamflow in a tropical, high-elevation catchment. However, our uncertainty estimation method can be generalized to any number of tracers across a range of disciplines.

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