An Engel condition for orderable groups

Let m,n be positive integers, v a multilinear commutator word and w=v^m. We prove that if G is an orderable group in which all w-values are n-Engel, then the verbal subgroup v(G) is locally nilpotent. We also show that in the particular case where v=x the group G is nilpotent (rather than merely locally nilpotent)

A restriction on centralizers in finite groups

For a given m>=1, we consider the finite non-abelian groups G for which |C_G(g):|<=m for every g in G\Z(G). We show that the order of G can be bounded in terms of m and the largest prime divisor of the order of G. Our approach relies on dealing first with the case where G is a non-abelian finite p-group. In that situation, if we take m=p^k to be a power of p, we show that |G|<=p^{2k+2} with the only exception of Q_8. This bound is best possible, and implies that the order of G can be bounded by a function of m alone in the case of nilpotent groups

Phytochemical Screening and Elemental Analysis of Aqueous and Methanolic Extracts of Datura innoxia Seeds and Leaves

The present study is aimed to screen the phytochemicals analysis and elements content of Datura innoxia seeds and leaves. The aqueous and methanol extracts were carried out by using the maceration method and soxhlet apparatus, respectively. Results of the study of Phytochemical screening revealed the presence of a high concentration of alkaloids, flavonoids, tannins, steroids and triterpines, and low concentration of saponin and coummarins. The elements in the leaves and seeds (K, Ca, S, Si, Cl, Fe, Al, P, Mg, Ti, Mn, Zn, Sr, Cu, V, Br, and Zr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectroscopy. K content was the highest in seeds (5.469 ± 0.021%), Ca and S the highest in leaves (2.461 ± 0.019 %, 1.254 ± 0.022 %, respectively). The elements Ti, Mn, Sr, V, Br, and Zr were detected in the leaves with range concentration 0.062-0.002 %. The elements Si, Cl, Fe, Al, P, Mg, and Zn concentration in seeds varied from 0.002 to 0.942% and in leaves varied from 0.014 to 0.346%. The concentration of these elements did not exceed the standard of dangerous toxic levels

Steering Behavior of an Articulated Amphibious All-Terrain Tracked Vehicle

This paper presents a study related to an Articulated Amphibious All-Terrain Tracked Vehicle (ATV) characterized by a modular architecture. The ATV is composed by two modules: The first one hosts mainly the vehicle engine and powertrain components, meanwhile the second one can be used for goods transportation, personnel carrier, crane and so on. The engine torque is transmitted to the front axle sprocket wheel of each module and finally distributed on the ground through a track mechanism. The two modules are connected through a multiaxial joint designed to guarantee four relative degrees of freedom. To steer the ATV, an Electro Hydraulic Power System (EHPS) is adopted, thus letting the vehicle steerable on any kind of terrain without a differential tracks speed. The paper aims to analyze the steady-state lateral behavior of the ATV on a flat road, through a non-linear mathematical vehicle model built in Matlab/Simulink environment. The model describes the vehicle main planar motion and the interaction between the two modules through the application of a hydraulic steering torque. The model simulates steady-state handling maneuvers in Matlab/Simulink. Two scenarios are considered: One with the application of an open-loop hydraulic steering torque without any vehicle feedback; the second one with a closed-loop steering torque actuation based on the relative angle between the two modules (hitch angle). Finally, the influence of the ATV longitudinal speed on vehicle lateral characteristics is also presented

Adaptive Equivalent Consumption Minimization Strategy with Rule-based Gear Selection for the Energy Management of Hybrid Electric Vehicles Equipped with Dual Clutch Transmissions

Based on observations of the behaviour of the optimal solution to the problem of energy management for plug-in hybrid electric vehicles, a novel real-time Energy Management Strategy (EMS) is proposed. In particular, dynamic programming results are used to derive a set of rules aiming at reproducing the optimal gearshift schedule in electric mode while the Adaptive Equivalent Consumption Minimization Strategy (A-ECMS) is employed to decide the powertrain operating mode and the current gear when power from the internal combustion engine is needed. In terms of total fuel consumption, simulations show that the proposed approach yields results that are close to the optimal solution and also outperforms those of the A-ECMS, a well-known EMS. One of the main aspects that differentiates the strategy here proposed from previous works is the introduction of a model to use physical considerations to estimate the energy consumption during gearshifts in dual-clutch transmissions. This, together with a series of properly tuned fuel penalties allows the controller to yield results in which there is no gear hunting behaviour