Comparison of Feedback Control Strategies for Operation of Granulation Loops

Granulation is a particle enlargement process during which fine particles or atomizable liquids are converted into granules via a series of complex granulation mechanisms. In this paper, two feedback control strategies are implemented to make granulation loop processes more steady to operate, i.e., to suppress oscillatory behavior in the produced granule sizes. In the first control strategy, a classical proportional-integral (PI) controller is used, while in the second, a double-loop control strategy is used to control the median diameter of the granules leaving the granulator. The simulation results showed that using the proposed control design for the granulation loop can eliminate the oscillatory behaviour in the produced granule median diameter and make granulation loop processes more steady to operate. A comparison between the two proposed control strategies showed that it is preferable to use the double-loop control strategy.

On Nonlinear Forced Impulsive Differential Equations under Canonical and Non-Canonical Conditions

This study is connected with the nonoscillatory and oscillatory behaviour to the solutions of nonlinear neutral impulsive systems with forcing term which is studied for various ranges of of the neutral coefficient. Furthermore, sufficient conditions are obtained for the existence of positive bounded solutions of the impulsive system. The mentioned example shows the feasibility and efficiency of the main results.

Statistical Scrutiny of Particle Spectra in ep Collisions

Charged particle multiplicity distributions in positron–proton deep inelastic scattering at a centre-of-mass energy s = 300 GeV, measured in the hadronic centre-of-mass frames and in different pseudorapidity windows are studied in the framework of two statistical distributions, the shifted Gompertz distribution and the Weibull distribution. Normalised moments, normalised factorial moments and the H-moments of the multiplicity distributions are determined. The phenomenon of oscillatory behaviour of the counting statistics and the Koba-Nielsen-Olesen (KNO) scaling behaviour are investigated. This is the first such analysis using these data. In addition, projections of the two distributions for the expected average charged multiplicities obtainable at the proposed future ep colliders.

Oscillations in Planar Deficiency-One Mass-Action Systems

Whereas the positive equilibrium of a planar mass-action system with deficiency zero is always globally stable, for deficiency-one networks there are many different scenarios, mainly involving oscillatory behaviour. We present several examples, with centers or multiple limit cycles.

Numerical Approach for Differential-Difference Equations having Layer Behaviour with Small or Large Delay using Non-Polynomial Spline

A numerical approach is suggested for the layer behaviour differential-difference equations with small and large delays in the differentiated term. Using the non-polynomial spline, the numerical scheme is derived. The discretization equation is constructed using the first order derivative continuity at non-polynomial spline internal mesh points. A fitting parameter is introduced into the scheme with the help of the singular perturbation theory to minimize the error in the solution. The maximum errors in the solution are tabulated to verify the competence of the numerical method relative to the other methods in literature. We also focused on the impact of large delays on the layer behaviour or oscillatory behaviour of solutions using a special mesh with and without fitting parameter in the proposed scheme. Graphs show the effect of the fitting parameter on the solution layer.

The damping and structural properties of dragonfly and damselfly wings during dynamic movement

For flying insects, stability is essential to maintain the orientation and direction of motion in flight. Flight instability is caused by a variety of factors, such as intended abrupt flight manoeuvres and unwanted environmental disturbances. Although wings play a key role in insect flight stability, little is known about their oscillatory behaviour. Here we present the first systematic study of insect wing damping. We show that different wing regions have almost identical damping properties. The mean damping ratio of fresh wings is noticeably higher than that previously thought. Flight muscles and hemolymph have almost no ‘direct’ influence on the wing damping. In contrast, the involvement of the wing hinge can significantly increase damping. We also show that although desiccation reduces the wing damping ratio, rehydration leads to full recovery of damping properties after desiccation. Hence, we expect hemolymph to influence the wing damping indirectly, by continuously hydrating the wing system.