450 research outputs found
Nonlinear H∞ Optimal Control Scheme for an Underwater Vehicle with Regional Function Formulation
No full textA conventional region control technique cannot meet the demands for an accurate tracking performance in view of its inability to accommodate highly nonlinear system dynamics, imprecise hydrodynamic coefficients, and external disturbances. In this paper, a robust technique is presented for an Autonomous Underwater Vehicle (AUV) with region tracking function. Within this control scheme, nonlinear H∞ and region based control schemes are used. A Lyapunov-like function is presented for stability analysis of the proposed control law. Numerical simulations are presented to demonstrate the performance of the proposed tracking control of the AUV. It is shown that the proposed control law is robust against parameter uncertainties, external disturbances, and nonlinearities and it leads to uniform ultimate boundedness of the region tracking error
Tracking Control Scheme for Multiple Autonomous Underwater Vehicles Subject to Union of Boundaries
No full textAbstractThis paper presents a new region boundary-based tracking control for Multiple Autonomous Underwater Vehicles (MAUVs). The proposed controller enables MAUVs to track a moving target formed by the union of two or more boundaries. In this case, multiplicative potential energy function is used to unite the whole boundaries. Moreover, each underwater vehicle navigates into a specific position on the boundary lines or surfaces while the target itself is moving. A non-negative Lyapunov-like function is presented for stability analysis of the MAUVs. Simulation results on 6 degrees-of-freedom AUVs are presented to illustrate the performance of new tracking control scheme
On abelian group actions with TNI-centralizers
No full textGüloğlu, İsmail Şuayip (Dogus Author)A subgroup H of a group G is said to be a TNI-subgroup if for any Let A be an abelian group acting coprimely on the finite group G by automorphisms in such a way that for all is a solvable TNI-subgroup of G. We prove that G is a solvable group with Fitting length h(G) is at most . In particular whenever is nonnormal. Here, h(G) is the Fitting length of G and is the number of primes dividing A counted with multiplicities
Action of a frobenius-like group with kernel having central derived subgroup
No full textGüloğlu, İsmail Şuayip (Dogus Author)A finite group FH is said to be Frobenius-like if it has a nontrivial nilpotent normal subgroup F with a nontrivial complement H such that [F, h] = F for all nonidentity elements h is an element of H. Suppose that a finite group G admits a Frobenius-like group of auto-morphisms FH of coprime order with [F', H] = 1. In case where C-G( F) = 1 we prove that the groups G and C-G( H) have the same nilpotent length under certain additional assumptions
Frobenius groups of automorphisms with almost fixed point free kernel
No full textGüloğlu, İsmail Şuayip (Dogus Author)Let FH be a Frobenius group with kernel F and complement H, acting coprimely on the finite solvable group G by automorphisms. We prove that if C-G(H) is of Fitting length n then the index of the n-th Fitting subgroup F-n(G) in G is bounded in terms of vertical bar C-G(F)vertical bar and vertical bar F vertical bar. This generalizes a result of Khukhro and Makarenko [6] which handles the case n = 1
Efficient Detection of Robot Kidnapping in Range Finder-Based Indoor Localization Using Quasi-Standardized 2D Dynamic Time Warping
No full textThis paper proposes an augmented online approach to detect kidnapping events within range-finder-based indoor localization. The method is specifically designed for an Internet of Things (IoT)-Aided Robotics Platform that enables the system to detect kidnapping across all time instances of an indoor mobile robotic operation with high accuracy and maintain a high accuracy in the face of relocalization failures. The approach is based on similarity degree of geometry shape of the environment obtained from range scan data between two consecutive time instances. The proposed approach named Quasi-Standardized Two-Dimensional Dynamic Time Warping (QS-2DDTW) is based on the Multidimensional Dynamic Time Warping (MD-DTW) with homogeneity variance test imbued in it. A series of simulations are preformed against maximum current weight, measurement entropy, and the four metrics in metric based detector. The result shows that the proposed method yields high performance in terms of its ability to distinguish kidnapping condition from normal condition and that it has low dependency towards relocalization process, thus ensures the accuracy of detection is not disturbed by relocalization
David Bellos’ indirect translation of Ismail Kadare’s The file on H : a contextual analysis
No full textThis article is a linguistic study of David Bellos’ indirect translation of Ismail Kadare’s The File on H (1997), a novel first published in 1980-1981 in the Albanian literary review Nëntori, and translated into English on the basis of Jusuf Vrioni’s French version, Le Dossier H (1989). Also called "double", "mediated" or "second-hand", indirect translation is an understudied phenomenon, often criticised by scholars because of its greater distance to the original. Cay Dollerup (2000: 23), for example, argues that the grammatical structure of the mediating language (ML) obscures the distinctions made in the source language (SL), and that possible "mistakes" in the ML may be repeated in the target language (TL). Do fidelity and loyalty to the author become weakened in Bellos’ indirect translation? To what extent is such weakening discernible linguistically? And does this particular case of indirect translation reveal notable patterns or recurring types of linguistic shifts between ST and TT? Showing that some of the features specific to Kadare’s Albanian writing are tempered in the doubly-translated English text, yet highlighting that similar shifts occur in the three language directions involved, this article demonstrates that changes between ST and TT may occur in indirect translation regardless of the strategies adopted by MT – thus challenging the hypothesis that linguistic shifts in indirect translation follow a single or consistent pattern
Groups of automorphisms with TNI-centralizers
No full textGüloğlu, İsmail, Şuayip (Dogus Author)A subgroup H of a finite group G is called a TNI-subgroup if NG(H)∩Hg=1 for any g∈G\NG(H). Let A be a group acting on G by automorphisms where CG(A) is a TNI-subgroup of G. We prove that G is solvable if and only if CG(A) is solvable, and determine some bounds for the nilpotent length of G in terms of the nilpotent length of CG(A) under some additional assumptions. We also study the action of a Frobenius group FH of automorphisms on a group G if the set of fixed points CG(F) of the kernel F forms a TNI-subgroup, and obtain a bound for the nilpotent length of G in terms of the nilpotent lengths of CG(F) and CG(H)
On the influence of fixed point free nilpotent automorphism groups
No full textGüloğlu, İsmail Şuayip (Dogus Author)A finite group FH is said to be Frobenius-like if it has a nontrivial nilpotent normal subgroup F with a nontrivial complement H such that for all nonidentity elements . Let FH be a Frobenius-like group with complement H of prime order such that is of prime order. Suppose that FH acts on a finite group G by automorphisms where in such a way that In the present paper we prove that the Fitting series of coincides with the intersections of with the Fitting series of G, and the nilpotent length of G exceeds the nilpotent length of by at most one. As a corollary, we also prove that for any set of primes , the upper -series of coincides with the intersections of with the upper -series of G, and the - length of G exceeds the -length of by at most one
Efficient Detection of Robot Kidnapping in Range Finder-Based Indoor Localization Using Quasi-Standardized 2D Dynamic Time Warping
No full textThis paper proposes an augmented online approach to detect kidnapping events within range-finder-based indoor localization. The method is specifically designed for an Internet of Things (IoT)-Aided Robotics Platform that enables the system to detect kidnapping across all time instances of an indoor mobile robotic operation with high accuracy and maintain a high accuracy in the face of relocalization failures. The approach is based on similarity degree of geometry shape of the environment obtained from range scan data between two consecutive time instances. The proposed approach named Quasi-Standardized Two-Dimensional Dynamic Time Warping (QS-2DDTW) is based on the Multidimensional Dynamic Time Warping (MD-DTW) with homogeneity variance test imbued in it. A series of simulations are preformed against maximum current weight, measurement entropy, and the four metrics in metric based detector. The result shows that the proposed method yields high performance in terms of its ability to distinguish kidnapping condition from normal condition and that it has low dependency towards relocalization process, thus ensures the accuracy of detection is not disturbed by relocalization
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