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An adaptive neural control scheme without backstepping is proposed for the air-breathing hypersonic vehicle subject to input constraints. To estimate the unknown nonlinearity of velocity subsystem and altitude subsystem, two radial basis function neural networks (RBFNNs) are constructed. Since the complex backstepping design steps are not needed, the proposed control structure is quite concise and the problem of “explosion of terms” is avoided. Moreover, a novel nonlinear auxiliary system is constructed to solve the problem of input constraints. The advantage of the proposed auxiliary system is that its high-order form has good performance and the parameter tuning is relatively easy. Simulation results show that the designed controllers achieve stable tracking of reference commands with good performance.

A freshwater Indian air breathing catfish, Clarias batrachus was subjected to low (3.75 mg/L) and high (18.75 mg/L) sub lethal dose of lead nitrate for short (24, 48 and 96 hours) and long term (15, 30 and 45 days) treatment to study serum biochemical features. All the variations were more dependent on the dose in comparison to the duration. At the end of the experiment, serum glucose, serum cholesterol and serum urea levels raised (p

Air-Breathing Electric Thrusters (ABET) diagnostics is addressed, with on-ground prototypes in mind. It is based on detailed volume averaged Global Models and focuses on emission spectroscopy. Notably, the obtained optical emission spectroscopy diagnostics tools give important information about the thruster propellant constitution and also the ionization degree of each constituent. This allows for trade-off between various prototypes on the basis of their characterization and optimization.

All air breathing vertebrates are endowed with pulmonary surfactants, surface-active lipoprotein complexes formed by type II alveolar cells. Surfactants are deposited in clearly defined areas on the luminal aspect of blood vessels, producing hydrophobic spots. Gas nanobubbles measuring 5–100 nm form spontaneously on the smooth hydrophobic spot from dissolved gas. Bubbles nucleate and grow at these spots after decompression from high pressure. Proteins with hydrophobic regions circulating in the blood will adhere to the gas phase-plasma interface. Deformation of their secondary and tertiary configuration will present them as foreign molecules or autoantigens. Components of the intact protein which are also present in a deformed protein may be recognized as foreign too. This process is proposed as the trigger for autoimmune diseases. The presence of autoimmune disease in air breathing vertebrates, increased autoimmunity and the elevated risk of decompression sickness with age, as well as variable sensitivity to both diseases, can be matched with the appearance of surfactant spots. Eliminating these spots may provide protection against both diseases.

Study of atmospheric remnants in the low Earth orbit region (~200 km altitude) using Global Models, with application to electric thrusters of in situ resources utilization type.

Time of Cochlear Implant Use Obtained From Data Logging and Word Discrimination Performance of Children

A year young boy presented to our ENT department OPD with history of a penetrating metallic foreign body in the neck since yrs On wound exploration under local anesthesia the foreign body was not identified It was removed with the help of a magnet after years nbsp

In this paper, a novel control scheme for the flexible air-breathing hypersonic vehicle (FAHV) using adaptive interval type-2 fuzzy logic system (AIT2-FLS) is proposed to reduce the side effects of measurement noises in the velocity channel and altitude channel as well as flexible dynamics in real applications. After input-output linearization of the longitudinal model of FAHV, the dynamic inversion controller is formulated to track the reference commands based on state feedback. The AIT2-FLS is further developed to deal with the model uncertainties and input errors. Besides, the state estimator is applied to estimate the true values of the corrupted outputs. The stability characteristics of both the controller and the state estimator are analyzed. The whole control scheme is finally obtained through combining the controller and the state estimator based on the separation principle. Simulation results demonstrate the robustness of our proposed control scheme against measurement noises and flexibilities.

A novel disturbance rejection control scheme is proposed to address the robust attitude control problem for the air-breathing hypersonic vehicle (AHV) with mismatched disturbances. The attitude control system is decomposed into two subsystems, the outer-loop subsystem and inner-loop subsystem. The predictive sliding mode control (PSMC) is utilized to attenuate mismatched model uncertainties imposed on the outer-loop subsystem. Afterward, a novel NDO based PSMC (NDO-PSMC) is proposed to tackle the mismatched disturbances with remarkable influence on the inner-loop subsystem, and then the effectiveness and the stability of NDO-PSMC are demonstrated. Finally, simulation results demonstrate the effectiveness and robustness of the proposed robust attitude control scheme.