Periodic response of nonlinear systems

A procedure is developed to determine approximate periodic solutions of autonomous and non-autonomous systems. The trignometric collocation method (TCM) is formalized to allow for the analysis of relatively small order systems directly in physical coordinates. The TCM is extended to large order systems by utilizing modal analysis in a component mode synthesis strategy. The procedure was coded and verified by several check cases. Numerical results for two small order mechanical systems and one large order rotor dynamic system are presented. The method allows for the possibility of approximating periodic responses for large order forced and self-excited nonlinear systems

Model-Based Adaptive Tracking Control of Linear Time-Varying System with Uncertainties

https://scholarlycommons.pacific.edu/soecs-facbooks/1016/thumbnail.jp

IOT Based Intelligent Bin for Smart Cities

The method of connecting the objects or things through wireless connectivity, Internet called Internet Of Things. Nowadays a variety of tasks are based on IOT. Cities in the world are becoming smarter by implementing the things around using IOT. This is a new trend in technology. Smart cities include obstacle tracking, object sensing, traffic control, tracking of our activities, examining the baby, monitoring home lights and so on. One of the objective of smart cities is keeping the environment clean and neat. This aim is not fulfilled without the garbage bin management system. Hence the paper “IOT Based Intelligent Bin for Smart Cities” has been developed. Bin management is one of the major applications of IOT. Here sensors are connected to the all the bins at different areas. It senses the level of garbage in bin. When it reaches threshold a message is sent via GSM to the concerned person to clean it as soon as possible. The completed task is done in LabVIEW environment

Implementation of Fuzzy Based Simulation for Clone Detection in Wireless Sensor Networks

Wireless sensor networks are usually left unattended and serve hostile environment, therefore can easily be compromised. With compromised nodes an attacker can conduct several inside and outside attacks. Node replication attack is one of them which can cause severe damage to wireless sensor network if left undetected. This paper presents fuzzy based simulation framework for detection and revocation of compromised nodes in wireless sensor network. Our proposed scheme uses PDR statistics and neighbor reports to determine the probability of a cluster being compromised. Nodes in compromised cluster are then revoked and software attestation is performed.Simulation is carried out on MATLAB 2010a and performance of proposed scheme is compared with conventional algorithms on the basis of communication and storage overhead. Simulation results show that proposed scheme require less communication and storage overhead than conventional algorithms

Nonlinear Dynamic Model-Based Adaptive Control of a Solenoid-Valve System

In this paper, a nonlinear model-based adaptive control approach is proposed for a solenoid-valve system. The challenge is that solenoids and butterfly valves have uncertainties in multiple parameters in the nonlinear model; various kinds of physical appearance such as size and stroke, dynamic parameters including inertia, damping, and torque coefficients, and operational parameters especially, pipe diameters and flow velocities. These uncertainties are making the system not only difficult to adjust to the environment, but also further complicated to develop the appropriate control approach for meeting the system objectives. The main contribution of this research is the application of adaptive control theory and Lyapunov-type stability approach to design a controller for a dynamic model of the solenoid-valve system in the presence of those uncertainties. The control objectives such as set-point regulation, parameter compensation, and stability are supposed to be simultaneously accomplished. The error signals are first formulated based on the nonlinear dynamic models and then the control input is developed using the Lyapunov stability-type analysis to obtain the error bounded while overcoming the uncertainties. The parameter groups are updated by adaptation laws using a projection algorithm. Numerical simulation results are shown to demonstrate good performance of the proposed nonlinear model-based adaptive approach and to compare the performance of the same solenoid-valve system with a non-adaptive method as well

Chaos in a Magnetic Pendulum Subjected to Tilted Excitation and Parametric Damping

The effect of tilted harmonic excitation and parametric damping on the chaotic dynamics in an asymmetric magnetic pendulum is investigated in this paper. The Melnikov method is used to derive a criterion for transition to nonperiodic motion in terms of the Gauss hypergeometric function. The regular and fractal shapes of the basin of attraction are used to validate the Melnikov predictions. In the absence of parametric damping, the results show that an increase of the tilt angle of the excitation causes the lower bound for chaotic domain to increase and produces a singularity at the vertical position of the excitation. It is also shown that the presence of parametric damping without a periodic fluctuation can enhance or suppress chaos while a parametric damping with a periodic fluctuation can increase the region of regular motions significantly

The compound (3-{5-[(2,5-dimethoxyphenyl)amino]-1,3,4-thiadiazolidin-2-yl}-5,8-methoxy-2H-chromen-2-one) inhibits the prion protein conversion from PrPC to PrPSc with lower IC50 in ScN2a cells

Published ArticlePrion diseases are fatal neurodegenerative disorders of the central nervous system characterized by the accumulation of a protease resistant form (PrPSc) of the cellular prion protein (PrPC) in the brain. Two types of cellular prion (PrPC) compounds have been identified that appear to affect prion conversion are known as Effective Binders (EBs) and Accelerators (ACCs). Effective binders shift the balance in favour of PrPC, whereas Accelerators favour the formation of PrPSc. Molecular docking indicates EBs and ACCs both bind to pocket-D of the SHaPrPC molecule. However, EBs and ACCs may have opposing effects on the stability of the salt bridge between Arg156 and Glu196/Glu200. Computational docking data indicate that the hydrophobic benzamide group of the EB, GFP23 and the 1-(3,3-dimethylcyclohexylidene)piperidinium group of the ACC, GFP22 play an important role in inhibition and conversion from SHaPrPC to SHaPrPSc, respectively. Experimentally, NMR confirmed the amide chemical shift perturbations observed upon the binding of GFP23 to pocket-D of SHaPrPC. Consistent with its role as an ACC, titration of GFP22 resulted in widespread chemical shift changes and signal intensity loss due to protein unfolding. Virtual screening of a ligand database using the molecular scaffold developed from the set of EBs identified six of our compounds (previously studied using fluorescence quenching) as being among the top 100 best binders. Among them, compounds 5 and 6 were found to be particularly potent in decreasing the accumulation SHaPrPSc in ScN2a cells with an IC50 of 35 mM and 20 mM