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Based on the principle of Lagrange mechanics, especially considering the effects of rotation damping and nonsynchronous damping, a radial 4-dimensional dynamic model of the flywheel bearing rotor system is proposed. Applying the Laplace eigenvalue method, the stability effects of rotational damping, nonsynchronous damping, and their coupling effects are investigated by means of root locus method. Under the control of the linear quadratic regulator, dynamical characteristics of the flywheel bearing rotor system with varied rotational damping and nonsynchronous damping are also studied. The results show that the rotation damping, nonsynchronous damping, and their coupling effects have vast and complex instability effects on high-speed flywheel bearing rotor system. However, there are three exceptions. The tiny proportional rotational damping, remaining below 12%, and the minuscule proportional co-nonsynchronous damping; the product of the nonsynchronous damping and the speed ratio below 5% both can enhance the stability of the system. Furthermore, in the situation that the counter-nonsynchronous damping is coupled with the large proportion of rotational damping, the stability of the system can also be boosted distinctly. On the other hand, the numerical experimental results show that the rotational damping and nonsynchronous damping have a beneficial effect on the flywheel system controlled by linear quadratic regulator. In addition, under the control of linear quadratic regulator, the transient dynamical behavior of the flywheel rotor system with rotational damping or co-nonsynchronous damping performed better than the flywheel rotor system with the coupled damping. The numerical simulations of the transient response of the flywheel rotor system under active control are consistent with some of the derived stability analysis results. The results about the stability analysis and the performance in vibration control give the suggestions for the instability control and fault detection of the system.

Power dissipation characteristics of Stockbridge dampers (SD) is one of the important indexes in anti-vibration work of transmission line. The study focuses on the optimization of the SD's power dissipation characteristics under the effect of multi-structure parameter coupling. The aeolian vibration of overhead transmission lines is uncertain and random in stochastic dynamics. According to Strouhal formula, the relationship between the vibration frequency of transmission lines and wind speed can be found out. Based on the Weibull wind speed probability distribution, the probability density function of the transmission line conductor and damper coupling system vibration frequency is derived. The SD is considered as a typical 2-dimension of stochastic dynamical system. Based on the random process generated by the power dissipation of the SD, the characteristics of power dissipation and SD's resonant frequencies are analyzed when the multi-structure parameters of the SD are coupled. And the diagrams of the power dissipation at various frequencies are obtained. Based on the probability density function of the vibration frequency of the overhead conductor and damper, the objective function, namely the mathematical expectation of power dissipation (E(PD)), of the optimizations for the SD's power dissipation under the coupling of multiple structural parameters is proposed for the first time according to the author's knowledge. Constraint conditions of the optimizations are built by the quantization processing. The energy dissipation characteristics of the dampers can be evaluated by E(PD), and the power dissipation of SD with different coupled dual structure parameters is optimized based on the proposed method. The optimal values or the optimal value intervals of different coupled dual structure parameters are found, which may provide practical data.

The stability analysis based on the root locus method is proposed to study the whirl motion of a breathing cracked rotor in different crack locations. By the multiple scales method, the eigen-value problem of the infinite order complex mode solutions of the breathing cracked rotor system is discussed. The Campbell diagrams, decay rate plots and roots locus plots of the finite approach from 1st order to 41th order complex mode solutions are compared to find that the 5th order finite approach of the complex mode solutions is the most efficient approximation order, which is verified by the ensuing numerical simulation of the transient response of the breathing cracked rotor system. The effects of the crack position on the stability of the whirl motion of the breathing cracked rotor are analyzed by the decay rate plot of the fifth order approach. The result shows that the crack position affects the super critical resonance region from the 2nd order to the 5th order complex mode, and has no effects on the 1st order complex mode of the whirl motion, and the vibration stability of the subcritical and critical resonance region are less affected. The super critical instability of the system in the crack position at 2 l / L = 0.75 is most affected by rotational damping. These results provide practical references for fault diagnosis, condition monitoring and dynamic balance control technology of heavy loading rotating machinery.

Long-term wind power time series (WPTS) simulation plays an important role in long-term grid planning. The study focuses on building a mixed simulation methodology for the long-term WPTS based on asymmetric fluctuations. First, we combine fixed threshold wavelet denoising with wavelet transform to get less noise and more detailed information. Second, a 4D fluctuation features clustering method (FFCM) is proposed to optimize the clustering results. In addition, based on multiple asymmetric function fitting models (AFFMs), an improved Markov Chain Monte Carlo (MCMC) method is proposed to prevent wind power ramp events. Numerical experimental results show that the average simulation error of simulated WPTS based on AFFMs is 3.02% lower than that of the symmetric function fitting model (SFFM). Therefore, the mixed simulation methodology can decrease the simulation error and improve the model accuracy in simulating long-term WPTS and provides a mathematical model for policy guidance on efficient use of wind resources.

The stability of the whirl motion of a breathing cracked rotor with the distinction of stationary damping and the asymmetric rotational damping is studied. By Lagrange’s principal, the motion equations are formed in rotational frame such that the multi-asymmetric system, i.e., asymmetric rotational damping and asymmetric time-periodic varying stiffness, is simplified to be a system with anisotropic damping and anisotropic time-periodical varying stiffness in rotational operation. Based on the multiple scales solution of the simplified whirling equation in moving frame, root locus method for stability analysis is proposed. Different from the former stability estimation method, the corresponding Campbell diagram, decay rate plot, and root locus plot of the fifth-order approach are derived to prove the effects of both crack depth and damping effects. The numerical results of the instabilizing effects of the crack depth are well agreeing with the previous studies. In addition, the destabilizing influence of the rotational damping on the breathing cracked rotor is presented for the first time.

The damping effects with the distinction of stationary damping and the anisotropic rotating damping on the dynamic stability of the rotating rotor with an open crack on the surface of the shaft is studied. The motion equations of the cracked rotor system are formed by Lagranges principal. Different from previous studies, the anisotropic system with the multi periodical varied coefficients is simplified by the moving frame method such that the stability analysis based on the root locus method can be applied. The corresponding Campbell diagram, decay rate plot and roots locus plot are derived to prove the destabilizing influence of both the rotational damping and the varied anisotropy ratio of the rotating damping. The effects of anisotropy of stiffness on the decisions of the critical range are also presented. The result with theoretical precision would not only generally provide practical applicability to crack detection and instability control of the heavy loading turbo-machinery system, but also give the suggestion that, the increased proportion and the aggravated anisotropy of the rotational damping due to the crack of the fatigue rotor should been taken into consideration on the modeling of cracked rotor system.

The angular acceleration is taken into the consideration for the modeling of equations of coupling vibration in rotational operation. The effects of angular acceleration on the amplitude of both lateral and torsion vibration of the breathing cracked rotor are studied for the first time. The torsion influence of unbalance orientation angles is especially studied during the modeling of the Breathing behavior model of the crack with the mass eccentricity. Different from the previous study, the effects of unbalance orientation angle on the lateral torsion coupling vibration of the breathing cracked rotor are compared by logarithmic spectrum diagrams. Parametric stability of the breathing cracked rotor associated with both unbalance orientation angle and accelerations in diverse level of mass eccentricity are presented, these works have not been seen before. The numerical parametrically stability results are verified by comparing with the dynamic response of the system.

Mobile node distribution prediction is participatory sensing system to carry on the key effective data collection and message forwarding, this paper presents a mobile node distribution algorithm based on social relations, and the algorithm uses multi node communication interactive evaluation way of rural sports project, realizing the comprehensive analysis of the project rationality. At the same time, using logical judgment matrix carries out modeling for the sensor and using programming way allocates the wireless sensor nodes cache, which can obtain serial port expansion circuit and physical platform. Finally, through the wireless communication experiment, this paper obtains the delay characteristic curve and the analysis accurate rate curve of data transmission, which provide a new communication and evaluation system for the development of rural sports. Introduction Participatory sensing appears a perception technology in recent years, it is also known as the center of human perception. Participatory sensing uses a variety of data acquisition equipment and intelligent mobile phone of integrated specific sensor, which carry out interactive or autonomous acquisition, classification, transmission and analysis for human social status information, and then making a smart decision, they provide a service for human life and social activities [1-3]. Using participatory sensing systems, and combined with wireless sensor network nodes distribution, this paper designs the evaluation process of the rural sports project, the overall design framework and ideas are shown in Figure 1. The results of output analysis Directed sensing Logic judgment

We give a new sparse penalty for high-dimensional nonparametric additive models and propose an efficient and practical algorithm with concrete expression even when the number of covariates is larger than the sample size. Moreover, some simulation results are illustrated, and we also analyze the theoretical properties and sparse oracle inequalities of the additive models without compatibility condition.