scholarly journals Modeling and Control of Malware Propagation in Wireless IoT Networks

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Qing Yan ◽  
Lipeng Song ◽  
Chenlu Zhang ◽  
Jing Li ◽  
Shanshan Feng

Wireless Internet of Things (IoT) devices densely populate our daily life, but also attract many attackers to attack them. In this paper, we propose a new Heterogeneous Susceptible-Exposed-Infected-Recovered (HSEIR) epidemic model to characterize the effect of heterogeneity of infected wireless IoT devices on malware spreading. Based on the proposed model, we obtain the basic reproduction number, which represents the threshold value of diffusion and governs that the malware is diffusion or not. Also, we derive the malware propagation scale under different cases. These analyses provide theoretical guidance for the application of defense techniques. Numerical simulations validated the correctness and effectiveness of theoretical results. Then, by using Pontryagin’s Minimum Principle, optimal control strategy is proposed to seek time-varying cost-effective solutions against malware outbreaks. More numerical results also showed that some control strategies, such as quarantine and vaccination, should be taken at the beginning of the malware outbreak immediately and become less necessary after a certain period. However, the repairing and fixing strategy, for example applying antivirus patches, would be keep on going constantly.

2019 ◽  
Vol 26 (11-12) ◽  
pp. 989-1000
Author(s):  
Pingxin Wang ◽  
Xiaoting Rui ◽  
Hailong Yu ◽  
Bo Li

Track assemblies are widely used to reduce vehicles’ ground pressure and improve their off-road performance. During off-road, the track tension has a significant effect on the performance of the crawler driving system. Previous control strategies only make use of the motions of partial road wheels. This paper develops a logical improvement to govern the motion of the track tensioner by using all road wheels. First, a dynamic model of the hydraulic-mechanism coupling system is established using the transfer matrix method for multibody systems and pressure-flow equations. Then, in order to get the angle of the idler arm, a modeling method of wheel envelope perimeter is developed, which is based on the locations of all wheels. Simulation results indicate that the control system maintains the wheel envelope perimeter almost constant while road wheels swing and decrease the possibility of peel-off and breakage of the track. It alleviates the track repeated stretch and keeps the tension in a stable range to reduce the fatigue damage. The control strategy can effectively reduce the peak value of the upper track tension during a vehicle passing through obstacles. This study suggests that the active track tensioning system can be implemented to improve the driving properties of tracked vehicles.


Author(s):  
D. F. Rancruel ◽  
M. R. von Spakovsky

Solid-Oxide-Fuel-Cell (SOFC) stacks respond in seconds to changes in load while the balance of plant subsystem (BOPS) responds in times several orders of magnitude higher. This dichotomy diminishes the reliability and performance of SOFC electrodes with changes in load. In the same manner current and voltage ripples which result from particular power electronic subsystem (PES) topologies and operation produce a negative effect on the SOFC stack subsystem (SS) performance. The difference in transient response among the sub-systems must be approached in a way which makes operation of the entire system not only feasible but ensures that efficiency and power density, fuel utilization, fuel conversion, and system response are optimal at all load conditions. Thus, a need exists for the development of transient component- and system-level models of SOFC based auxiliary power units (APUs), i.e. coupled BOPS, SS, and PES, and the development of methodologies for optimizing subsystem responses and for investigating system-interaction issues. In fact the transient process occurring in a SOFC based APU should be systematically treated during the entire creative process of synthesis, design, and operational control, leading in its most general sense to a dynamic optimization problem. This entails finding an optimal system/component synthesis/design, taking into account on- and off-design operation, which in turn entails finding an optimal control strategy and control profile for each sub-system/component and control variable. Such an optimization minimizes an appropriate objective function while satisfying all system constraints. A preliminary set of chemical, thermal, electrochemical, electrical, and mechanical models based on first principles and validated with experimental data have been developed and implemented using a number of different platforms. These models have been integrated in order to be able to perform component, subsystem, and system analyses as well as develop optimal syntheses/designs and control strategies for transportation and stationary SOFC based APUs. Some pertinent results of these efforts are presented here.


Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2358 ◽  
Author(s):  
Omar Mohamed ◽  
Ashraf Khalil

This paper reviews the modeling techniques and control strategies applied to gas turbine power generation plants. Recent modeling philosophies are discussed and the state-of-the-art feasible strategies for control are shown. Research conducted in the field of modeling, simulation, and control of gas turbine power plants has led to notable advancements in gas turbines’ operation and energy efficiency. Tracking recent achievements and trends that have been made is essential for further development and future research. A comprehensive survey is presented here that covers the outdated attempts toward the up-to-date techniques with emphasis on different issues and turbines’ characteristics. Critical review of the various published methodologies is very useful in showing the importance of this research area in practical and technical terms. The different modeling approaches are classified and each category is individually investigated by reviewing a considerable number of research articles. Then, the main features of each category or approach is reported. The modern multi-variable control strategies that have been published for gas turbines are also reviewed. Moreover, future trends are proposed as recommendations for planned research.


2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Satyam Paul ◽  
Wen Yu ◽  
Xiaoou Li

This paper provides an overview of building structure modeling and control under bidirectional seismic waves. It focuses on different types of bidirectional control devices, control strategies, and bidirectional sensors used in structural control systems. This paper also highlights the various issues like system identification techniques, the time-delay in the system, estimation of velocity and position from acceleration signals, and optimal placement of the sensors and control devices. The importance of control devices and its applications to minimize bidirectional vibrations has been illustrated. Finally, the applications of structural control systems in real buildings and their performance have been reviewed.


2012 ◽  
Vol 12 (2) ◽  
pp. 51-68 ◽  
Author(s):  
Vladimir Monov ◽  
Blagoy Sokolov ◽  
Stefan Stoenchev

Abstract The paper presents an overview of the current methodology and practice in modeling and control of the grinding process in industrial ball mills. Basic kinetic and energy models of the grinding process are described and the most commonly used control strategies are analyzed and discussed.


Sign in / Sign up

Export Citation Format

Share Document