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The work is initiated by the physical applications. We investigate the controllability of the system x˙ = f(x) + B(t)u, where B(t) = B1 cos wt + B2 sin wt. The control action has the special structure set by the physical applicat...
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The work is initiated by the physical applications. We investigate the controllability of the system x˙ = f(x) + B(t)u, where B(t) = B1 cos wt + B2 sin wt. The control action has the special structure set by the physical application. For example, the similar control actions exist in the problems of theaircraft landing in the conditions of wind disturbance, or changing the incline of the orbit plane of the space satellite. The article describes the controllability specifications for theproblem in the form of the corresponding theorems.
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This paper examines some of the deficiencies of the pole-placement self-tuning controller, particularly for the control of nonlinear processes. A comparison is made with switched multiple-model control and a local controller netwo...
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This paper examines some of the deficiencies of the pole-placement self-tuning controller, particularly for the control of nonlinear processes. A comparison is made with switched multiple-model control and a local controller network, based on the local model network. The difference between the realisations of the local networks is also examined. All these approaches are applied for the control of the continuous stirred tank reactor.
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We give a criterion that is sufficient for controllability of multipartite quantum systems. We generalize the graph infection criterion to the quantum systems that cannot be described with the use of a graph theory. We introduce t...
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We give a criterion that is sufficient for controllability of multipartite quantum systems. We generalize the graph infection criterion to the quantum systems that cannot be described with the use of a graph theory. We introduce the notation of hypergraphs and reformulate the infection property in this setting. The introduced criterion has a topological nature and therefore it is not connected to any particular experimental realization of quantum information processing.
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Introduction: To evaluate the care and outcomes for patients presenting with floor of mouth (FOM) cancers. Methods: In this Ethics-approved audit, all eligible patients were evaluated with eligibility defined as having a squamous ...
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Introduction: To evaluate the care and outcomes for patients presenting with floor of mouth (FOM) cancers. Methods: In this Ethics-approved audit, all eligible patients were evaluated with eligibility defined as having a squamous cell carcinoma originating in the FOM. Patient, disease and treatment factors were defined. Primary end points were ultimate local/regional control and cancer-specific survival. These were analysed according to the Kaplan-Meier method. The log-rank test was used to determine statistical significance between survival curves. Multivariate analysis was conducted using Cox regression. Results: A total of 157 patients were eligible for analysis, 76% males and 24% females, with 38 (24%) having a prior diagnosis of cancer. Surgery was performed in 126 patients (54 with pre/postoperative radiotherapy), radiotherapy only in 30 patients and chemotherapy only in 1 patient. Surgery had the best local control (85%), with 23/30 (77%) patients having radiotherapy failing locally. Ultimate regional control was achieved in 89% of patients, while new primaries occurred in 45 (29%) Conclusions: Surgery remains an essential component of the treatment of patients with FOM cancers, with a high likelihood of other cancers developing.
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Flinders Ranges, southeast Australia, with the goal of improving our understanding of crustal structure, rheology, and the mechanism responsible for the localized intraplate deformation that characterizes this region. A subset of ...
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Flinders Ranges, southeast Australia, with the goal of improving our understanding of crustal structure, rheology, and the mechanism responsible for the localized intraplate deformation that characterizes this region. A subset of P- and S-wave traveltimes is inverted to jointly recover earthquake hypocenters, P-wave velocity structure and v_p/v_s anomalies. The P-wave velocity model reveals a spatial correlation between major negative velocity perturbations and concentrations of seismicity. In particular, a cluster of seismicity is observed within a distinct low velocity region between the Archean-Mesoproterozoic Gawler Craton and the Palaeo-Mesoproterozoic Curnamona Province, from 7 to 20 km depth. We postulate that this may be associated with a pre-existing structural weakness in the crust that arises primarily from rifting between the Curnamona Province and the Gawler Craton. Another area characterized by a high level of seismicity overlies a major sequence of N-S trending Ross-Delamerian thrust faults, which correspond to a band of low v_p and particularly v_p/v_s. The lack of evidence for elevated heat flows in both of these seismogenic regions suggests that thermally induced weakness is unlikely to play a dominant role. Instead, the dynamic behavior of this intraplate region appears to be caused by a serendipitously oriented regional stress field, provided by far field forces that originate from the boundary between the Pacific and Australian plates, which acts upon preexisting structural weaknesses in the lithosphere.
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We present analytical and numerical investigations of two anti-symmetrically coupled 1D Swift-Hohenberg equations (SHEs) with cubic nonlinearities. The SHE provides a generic formulation for pattern formation at a characteristic l...
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We present analytical and numerical investigations of two anti-symmetrically coupled 1D Swift-Hohenberg equations (SHEs) with cubic nonlinearities. The SHE provides a generic formulation for pattern formation at a characteristic length scale. A linear stability analysis of the homogeneous state reveals a wave instability in addition to the usual Turing instability of uncoupled SHEs. We performed weakly nonlinear analysis in the vicinity of the codimension-two point of the Turing-wave instability, resulting in a set of coupled amplitude equations for the Turing pattern as well as left- and right-traveling waves. In particular, these complex Ginzburg-Landau-type equations predict two major things: there exists a parameter regime where multiple different patterns are stable with respect to each other and that the amplitudes of different patterns interact by local mutual suppression. In consequence, different patterns can coexist in distinct spatial regions, separated by localized interfaces. We identified specific mechanisms for controlling the position of these interfaces, which distinguish what kinds of patterns the interface connects and thus allow for global pattern selection. Extensive simulations of the original SHEs confirm our results. Published by AIP Publishing.
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In this paper, we present a method of locomotion control for underwater vehicles that are propelled by a periodic deformation of the vehicle body, which is similar to the way a fish moves. We have developed control laws employing...
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In this paper, we present a method of locomotion control for underwater vehicles that are propelled by a periodic deformation of the vehicle body, which is similar to the way a fish moves. We have developed control laws employing “extremum seeking” for two different “fish” models. The first model consists of three rigid body links and relies on a 2-degree-of-freedom (DOF) movement that propels the fish without relying on vortices. The second fish model uses a Joukowski airfoil that has only 1 DOF in its movement and, thus, relies on vortex shedding for propulsion. We achieve model-free and position-free “source seeking,” and, if position is available, navigation along a predetermined path.
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We propose a scheme to achieve extremely asymmetric electron localization during molecular dissociations. Hydrogen molecular ion (H_2~+) dissociation is investigated theoretically. A THz pulse is used to steer the electron motion ...
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We propose a scheme to achieve extremely asymmetric electron localization during molecular dissociations. Hydrogen molecular ion (H_2~+) dissociation is investigated theoretically. A THz pulse is used to steer the electron motion after the molecular ion is excited by an ultrashort ultraviolet laser pulse. A high probability, as high as 99.3%, to localize electrons on one of the two nuclei is demonstrated, with a dissociation probability of 6.14% and almost no ionization, by optimizing the peak intensities and time delay of the two pulses. Even when the total dissociation probability is increased to 25.6%, more than 96.3% electrons can be localized in all dissociation events. These results represent a significant advancement in the electronic dynamics control in molecules.
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Anderson localization of light has been demonstrated in a few different dielectric materials and lithographically fabricated structures. However, such localization is difficult to control, and requires strong magnetic fields or no...
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Anderson localization of light has been demonstrated in a few different dielectric materials and lithographically fabricated structures. However, such localization is difficult to control, and requires strong magnetic fields or nonlinear optical effects, and electronic control has not been demonstrated. Here, we show control of optical Anderson localization using charge carriers injected into more than 100 submicrometre-scale p–n diodes. The diodes are embedded into the crosssection of the optical waveguide and are fabricated with a technology compatible with the current electronics industry. Large variations in the output signal, exceeding a factor of 100, were measured with 1 V and a control current of 1 mA. The transverse footprint of our device is only 0.125 mm~2, about five orders of magnitude smaller than optical two-dimensional lattices. Whereas all-electronic localization has a narrow usable bandwidth, electronically controlled optical localization can access more than a gigahertz of bandwidth and creates new possibilities for controlling localization at radiofrequencies, which can benefit applications such as random lasers, optical limiters, imagers, quantum optics and measurement devices.
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