WEIGHTED ENDPOINT INEQUALITIES FOR MULTILINEAR MARCINKIEWICZ INTEGRAL OPERATOR

Wenxin, Yu,Liu, Lanzhe Korean Mathematical Society 2008 대한수학회보 Vol.45 No.1

We prove a sharp inequality for some multilinear operator related to Marcinkiewicz integral operator. As application, we obtain the weighted norm inequality and L log L type estimate for the multilinear operator.

Fault Detection Based on a Combined Approach of FA-CP-ELM with Application to Wind Turbine System

Wenxin Yu,Shoudao Huang,Junnian Wang 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.1

In this paper, a novel wind turbine (WT) fault detection method, based on the Partial Least Squares (PLS), Firefly Algorithm (FA), Chaos Map (CP) and Extreme Learning Machine (ELM), which is proposed and explained in detail. The proposed method includes two procedures: a WT mathematical model with PLS and a prediction model with FA-CP-ELM. Since the WT system is modeled as a system using PLS, the ELM has been optimized by the FA and CP to improve the predictive performance. Then, it’s calculated the residual between the mathematical model and the predicted model. If a fault occurs, the residual will increase accordingly and exceed the tolerance range. Hence, a fault can be detected quickly. To demonstrate the feasibility and effectiveness of the proposed approach, the wind turbine system is tested with a fault point set in this system. According to the results of the example, this proposed method is found to achieve better performance.

Weighted endpoint Inequalities for Multilinear Marcinkiewicz Integral Operator

Yu Wenxin,Lanzhe Liu 대한수학회 2008 대한수학회보 Vol.45 No.1

We prove a sharp inequality for some multilinear operatorrelated to Marcinkiewicz integral operator. As application, we obtain theweighted norm inequality and Llog L type estimate for the multilinear operator.

Fault Diagnosis of a Nonlinear Dynamic System Based on Sliding Mode

Yu, Wenxin,Wang, Junnian,Jiang, Dan The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.6

Actuator failures and the failures of controlled objects are often considered together. To overcome this limitation, a class of sliding mode observers for the fault diagnosis of nonlinear systems is designed in this paper. Due to the influence of the sliding mode function, the control strategy and the residual change of the observer exhibit certain trends governed by specific relations. Therefore, according to the changes in the control strategy and the observer residuals, the sensor and actuator faults in nonlinear systems can be determined. Finally, the effectiveness of the proposed method is verified based on simulations of a DC motor system.

Fault Diagnosis of a Nonlinear Dynamic System Based on Sliding Mode

Wenxin Yu,Junnian Wang,Dan Jiang 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.6

Actuator failures and the failures of controlled objects are often considered together. To overcome this limitation, a class of sliding mode observers for the fault diagnosis of nonlinear systems is designed in this paper. Due to the influence of the sliding mode function, the control strategy and the residual change of the observer exhibit certain trends governed by specific relations. Therefore, according to the changes in the control strategy and the observer residuals, the sensor and actuator faults in nonlinear systems can be determined. Finally, the effectiveness of the proposed method is verified based on simulations of a DC motor system.

Reliability‐aware service chaining mapping in NFV‐enabled networks

Yicen Liu,Yu Lu,Wenxin Qiao,Xingkai Chen 한국전자통신연구원 2019 ETRI Journal Vol.41 No.2

Network function virtualization can significantly improve the flexibility and effectiveness of network appliances via a mapping process called service function chaining. However, the failure of any single virtualized network function causes the breakdown of the entire chain, which results in resource wastage, delays, and significant data loss. Redundancy can be used to protect network appliances; however, when failures occur, it may significantly degrade network efficiency. In addition, it is difficult to efficiently map the primary and backups to optimize the management cost and service reliability without violating the capacity, delay, and reliability constraints, which is referred to as the reliability‐aware service chaining mapping problem. In this paper, a mixed integer linear programming formulation is provided to address this problem along with a novel online algorithm that adopts the joint protection redundancy model and novel backup selection scheme. The results show that the proposed algorithm can significantly improve the request acceptance ratio and reduce the consumption of physical resources compared to existing backup algorithms.

A STATE DETECTION METHOD OF INDUCTION MOTOR BASED ON PSO-BS-SMO

Guanglin Zhong,Wenxin Yu,JunNian Wang 한국자동차공학회 2024 International journal of automotive technology Vol.25 No.2

In order to improve the performance of sliding mode observer in detecting the state of induction motor, a state detectionmethod based on particle swarm optimization (PSO)-backstepping (BS)-sliding mode observer (SMO) is proposed in thispaper. In this method, the controller is constructed and the parameters of the control rate are optimized, so that the trackingaccuracy and robustness of the new observer are improved relative to conventional observer, exponential observer, PI andPID. Firstly, the state equation of the induction motor under stator and rotor winding fault and stator current sensor fault isestablished. Secondly, the new sliding mode observer is designed using the backstepping method based on the new reachinglaw. Then, the new fi tness function and PSO is used to optimize the parameters of the new sliding mode observer. Finally,the simulation comparison experiment of stator current state detection is carried out under the simulated fault condition ofinduction motor. The feasibility of the method is verifi ed by comparing the state tracking situation and the state detectionerror. The comparative experimental results show that the method has less jitter, stronger robustness, and higher state trackingaccuracy when detecting stator current states under diff erent faults.

Smart Anti-jamming Mobile Communication for Cloud and Edge-Aided UAV Network

( Zhiwei Li ),( Yu Lu ),( Zengguang Wang ),( Wenxin Qiao ),( Donghao Zhao ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.12

The Unmanned Aerial Vehicles (UAV) networks consisting of low-cost UAVs are very vulnerable to smart jammers that can choose their jamming policies based on the ongoing communication policies accordingly. In this article, we propose a novel cloud and edge-aided mobile communication scheme for low-cost UAV network against smart jamming. The challenge of this problem is to design a communication scheme that not only meets the requirements of defending against smart jamming attack, but also can be deployed on low-cost UAV platforms. In addition, related studies neglect the problem of decision-making algorithm failure caused by intermittent ground-to-air communication. In this scheme, we use the policy network deployed on the cloud and edge servers to generate an emergency policy tables, and regularly update the generated policy table to the UAVs to solve the decision-making problem when communications are interrupted. In the operation of this communication scheme, UAVs need to offload massive computing tasks to the cloud or the edge servers. In order to prevent these computing tasks from being offloaded to a single computing resource, we deployed a lightweight game algorithm to ensure that the three types of computing resources, namely local, edge and cloud, can maximize their effectiveness. The simulation results show that our communication scheme has only a small decrease in the SINR of UAVs network in the case of momentary communication interruption, and the SINR performance of our algorithm is higher than that of the original Q-learning algorithm.

A Dynamic Placement Mechanism of Service Function Chaining Based on Software-defined Networking

( Yicen Liu ),( Yu Lu ),( Xingkai Chen ),( Xi Li ),( Wenxin Qiao ),( Liyun Chen ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.10

To cope with the explosive growth of Internet services, Service Function Chaining (SFC) based on Software-defined Networking (SDN) is an emerging and promising technology that has been suggested to meet this challenge. Determining the placement of Virtual Network Functions (VNFs) and routing paths that optimize the network utilization and resource consumption is a challenging problem, particularly without violating service level agreements (SLAs). This problem is called the optimal SFC placement problem and an Integer Linear Programming (ILP) formulation is provided. A greedy heuristic solution is also provided based on an improved two-step mapping algorithm. The obtained experimental results show that the proposed algorithm can automatically place VNFs at the optimal locations and find the optimal routing paths for each online request. This algorithm can increase the average request acceptance rate by about 17.6% and provide more than 20-fold reduction of the computational complexity compared to the Greedy algorithm. The feasibility of this approach is demonstrated via NetFPGA-10G prototype implementation.

Health Status Evaluation of Catenary Based on Normal Fuzzy Matter-Element and Game Theory

Lingzhi Yi,Jian Zhao,Wenxin Yu,Guzong Long,Haoyi Sun,Wang Li 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.5

At present, there is no unifi ed standard for the health status evaluation of electrifi ed railway catenary in China. The current catenary evaluation model only considers quantitative detection indicators, without qualitative indicators such as weather, which is one-sided to some extent. Thus, an improved catenary status evaluation model is constructed with both quantitative indicators and qualitative indicators. In this evaluation model, the normal fuzzy matter-element method is used to determine the correlation value of each grade, and the weighted average principle is used to re-determine the status grade of catenary when the maximum correlation principle fails. Meanwhile, entropy weight method and particle swarm optimization algorithm to optimize analytic hierarchy process method are combined to improve the shortcomings of single weight method, and game theory is used to determine the subjective and objective weight coeffi cients, so as to reduce the infl uence of subjective experience. Select a Chinese railway catenary in 2018 as an example for verifi cation analysis, the results show that the model constructed in this paper can eff ectively help professionals to make correct judgments on the health status of catenary, and provide a new idea and method for the comprehensive evaluation of the catenary operation status, which has certain practicability