Adaptive Predictive Control Using Neural Network for a Class of Pure-feedback Systems in Discrete-time

10.1109/TNN.2008.2000446IEEE Transactions on Neural Networks1991599-1614ITNN

Robust Adaptive Control of a Class of Nonlinear Strict-feedback Discrete-time Systems with Exact Output Tracking

10.1016/j.automatica.2009.07.025Automatica45112537-2545ATCA

Fault estimation and accommodation for virtual sensor bias fault in image-based visual servoing using particle filter

This study develops a fault estimation and accommodation scheme for the image-based visual servoing (IBVS) system to eliminate the effects of the faults due to the image feature extraction task, which is named as bias virtual sensor fault. First, a bias virtual sensor fault in visual servoing is declared. Then, fault diagnosis (FD), which includes fault detection, isolation and estimation, is designed based on the means of particle filter (PF). Finally, a fault accommodation law is developed based on the information obtained from the fault estimation to compensate for the effects of the fault in the system. The proposed fault estimation and accommodation is verified through simulation and experimental studies, and the results show that the system can estimate and eliminate the unknown fault effects effectively

p-wave Holographic Superconductors and five-dimensional gauged Supergravity

We explore five-dimensional ${\cal N}=4$ $SU(2)\times U(1)$ and ${\cal N}=8$ SO(6) gauged supergravities as frameworks for condensed matter applications. These theories contain charged (dilatonic) black holes and 2-forms which have non-trivial quantum numbers with respect to U(1) subgroups of SO(6). A question of interest is whether they also contain black holes with two-form hair with the required asymptotic to give rise to holographic superconductivity. We first consider the ${\cal N}=4$ case, which contains a complex two-form potential $A_{\mu\nu}$ which has U(1) charge $\pm 1$. We find that a slight generalization, where the two-form potential has an arbitrary charge $q$, leads to a five-dimensional model that exhibits second-order superconducting transitions of p-wave type where the role of order parameter is played by $A_{\mu\nu}$, provided $q \gtrsim 5.6$. We identify the operator that condenses in the dual CFT, which is closely related to ${\cal N}=4$ Super Yang-Mills theory with chemical potentials. Similar phase transitions between R-charged black holes and black holes with 2-form hair are found in a generalized version of the ${\cal N}=8$ gauged supergravity Lagrangian where the two-forms have charge $q\gtrsim 1.8$.Comment: 35 pages, 14 figure

Detection of coupling misalignment by extended orbits

In this paper a ‘SpectraQuest’ demonstrator is used to introduce misalignment into a rotating machinery set-up. Depending on the coupling used in the set-up, angular and/or parallel misalignment can be brought in the rotating system. Traditionally, the data captured by accelerometers is transferred into the frequency domain in order to interpret the vibrations measured by the accelerometers. The frequency domain has proven its usefulness but even the time domain can come in handy to draw the right conclusions regarding to misalignment in a rotating set-up. Orbit plots display the integrated data captured by accelerometers, in order to display the movement of the rotating shaft. The influence of the misalignment and imbalance on these orbits will be discussed

Seroprevalence Of Human Immunodeficiency Virus Infection Among Tuberculosis Patients In The Nylon District Hospital Tuberculosis Treatment Centre

Background: Tuberculosis (TB) incidence in Cameroon is high with 32% of adult TB patients, all forms, co-infected with HIV. The Nylon District Hospital in Douala runs a centre for the diagnosis and treatment of TB since 2001 and a pioneer Human Immunodeficiency Virus (HIV)/Acquired Immune deficiency Syndrome (AIDS) management programme at district level since 2000. Objective: To determine the prevalence of HIV infection in TB patients from 2003 to 2006 and to analyse the pattern of TB/HIV co-infection rate over time. Design: A retrospective study. Setting: Nylon District Hospital, Douala, Cameroon. Results: The prevalence of HIV infection in TB patients was 51.6%. This was greater for patients living out of the Nylon Health District (P= 0.001). Smear positive pulmonary tuberculosis (SPPT) was the most frequent (65%) form of TB diagnosed but extrapulmonary tuberculosis (EPT) and smear negative pulmonary tuberculosis (SNPT) were more frequently associated with HIV co-infection (80% and 68.6% respectively). While men and women presented equally with TB, women (61.4%) were significantly (P< 0.0001) more TB/HIV co-infected than men (42%). The co-infection rate was highest among individuals aged 25-44 years (61.4%) and least among the 0-24 years age group (22.5%). The increase in TB/HIV co-infection rate is monotonic over time with a stronger trend among females aged 25-44 years (P= 0.037) and above 45 years (P= 0.001). Conclusion: The NDH selectively attracted HIV positive patients to adhere to their HIV programme. The creation of HIV / AIDS treatment units in institutions providing TB diagnosis and treatment services will reduce the movement of TB/HIV co-infected patients across provinces and health districts as well as enhancing TB/HIV co-infection diagnosis and notification. East African Medical Journal Vol. 85 (11) 2008: pp. 529-53

Acoustic black holes for relativistic fluids

We derive a new acoustic black hole metric from the Abelian Higgs model. In the non-relativistic limit, while the Abelian Higgs model becomes the Ginzburg-Landau model, the metric reduces to an ordinary Unruh type. We investigate the possibility of using (type I and II) superconductors as the acoustic black holes. We propose to realize experimental acoustic black holes by using spiral vortices solutions from the Navier-stokes equation in the non-relativistic classical fluids.Comment: 16 pages. typos corrected, contents expande