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This paper proposes an efficient sensorless speed estimation approach for electric servo drives based on the full-order nonsingular terminal sliding mode observer (FONTSM) with the application of DC motor drives. In this method, a specific full-order terminal sliding mode manifold is utilised for the observer design which results in the elimination of the chattering and avoiding the singularity phenomenon of conventional and terminal sliding modes. Here, speed and armature back emf can be directly estimated from the relevant observer’s inputs which are continuous instead of being discontinuous high-frequency “switching” signals. The efficiencies and advantages of this approach have been proven and validated in both simulation and experimental results.

This paper addresses the problem of nonlinear robust adaptive output feedback controller for a class of underactuated aerial vehicles with input and output constraints. To solve the problem, the modular design strategy is proposed for the control design. By using the neural networks (NNs) to approximate system uncertainties and observers to reconstruct system states, robust adaptive output feedback controllers are developed. By using a combination of saturation functions and barrier functions, input and output constraints are simultaneously dealt with. The design methodology shows that a cascaded system of an input-to-state stable (ISS) subsystem driven by an ultimate bounded (UB) subsystem enjoys ultimate boundedness property. In addition, the tracking error converges to adjustable neighbourhoods of the origin.

In our facile synthesis method, poly(vinylpyrrolidone)-protected Pt and Pt–Pd bimetallic nanoparticles with controllable polyhedral core–shell morphologies are precisely synthesized by the reduction of Pt and Pd precursors at a certain temperature in ethylene glycol with silver nitrate as structure-controlling agent. The Pt nanoparticles exhibited well-shaped polyhedral morphology with highly fine and specific nanostructures in the size range of 20 nm. Important evidences of core–shell configurations of the Pt–Pd core–shell nanoparticles were clearly characterized by high-resolution transmission electron microscopy (HRTEM) measurements. The results of HRTEM images showed that the core–shell Pt–Pd nanoparticles in the size range of 25 nm with polyhedral morphology were synthesized with the thin Pd shells of ∼3 nm in thickness as the atomic Pd layers grown on the Pt cores. Very interesting characteristics of surface structure of Pt nanostructures and Pt–Pd core–shell nanostructures with surface defects were...

Finding decision rules in weather prediction is an important issue besides using mathematical or statistical models and weather satellite data. It is dealt with this paper a method of analysing weather information system based on rough set reasoning and statistical method to support weather prediction. Firstly, some probability distributions of weather attributes will be verified and used for partition attribute value ranges using equal-probability percentiles. The solar terms in traditional East Asian point of view are used to determine types of decision weather attribute in the weather information system. Next, such an information system will be analyzed to produce a set of decision rules. After checking and verifying on collected weather dataset, it is shown that the method of analyzing is of significantly efficiency.

Ion homeostasis is considered to be one of the most important mechanisms underlying salt stress tolerance. We used the Steptoe × Morex barley doubled haploid population to screen for genetic variation in response to salinity stress at an early development stage in a hydroponics system, focusing on ion homeostasis. Salinity induced a strong adverse effect on growth of the parents and their derived population, with Steptoe as the more tolerant parent. Steptoe maintained higher concentrations of K+, Na+ and Cl− in the roots and a similar shoot/root ion ratio (

We describe the process of modification of the platinum (Pt) nanowire surface and subsequent immobilisation of enzyme glucose oxidase (GOx) on Pt nanowires (PtNWs) for direct glucose measurement. A cyclic voltammetry technique was used to measure electrochemical oxidation between GOx and glucose. PtNW arrays were first fabricated and then functionalised with cysteamine' which in turn acted as a chemical linkage for the enzyme conjugation. Afterward' the enzyme modified PtNWs arrays were subjected to the model test to check the effect of the process modification. The cyclic voltammograms of GOx immobilised Pt chips in PBS (1M' pH of 7) showed the most stable result. The enzymatic modified PtNW electrodes were then successfully determined glucose in diabetic blood samples with the concentrations from 125 μM to 16.5 mM' a deviation of ± 3%. The obtained results clearly indicate the potential of a next-generation of glucose sensor based on PtNW in application diabetic diagnosing. Refereed/Peer-reviewed

Novel Pt and Pd Based Core-Shell Catalysts with Critical New Issues of Heat Treatment, Stability and Durability for Proton Exchange Membrane Fuel Cells and Direct Methanol Fuel Cells

In the present work, PtRu/C-CNTs catalyst samples were studied for potential applications in direct methanol fuel cells (DMFCs). Carbon nanotubes (CNTs) were treated by H2SO4 98% and HNO3 65% at different temperatures and with different stirring periods. As a result, the PtRu/C-CNTs catalyst was successfully synthesized by using H2PtCl6 and RuCl3 precursors with the efficient reduction of NaBH4 agent in ethylene glycol (e.g.). In addition, we controlled the ratios of treated-CNTs on carbon vulcan XC-72 treated-CNTs substrate (C-CNTs) with the different values: 50 wt%, 25 wt%, and 12.5 wt%, respectively. The PtRu/C-CNTs electrocatalyst samples were investigated by experimental methods including x-ray diffraction (XRD), transmission electron microscopy (TEM), and cyclic voltammetry (CV). Importantly, the CV results show the best treated-CNTs and the most suitable ratio of CNTs composition on C-CNTs substrate to be controlled in order to produce various efficient PtRu/C-CNTs catalysts with high catalytic activity for DMFCs.

Among biosensors of various types, the silicon nanowire field–effect transistor (SiNW–FET) is believed to be the most sensitive and powerful device for bio–applications. In fact, these devices have demonstrated the ability to detect a variety of analyses such as particular DNA sequences, cancer biomarkers and larger entities such as viruses. The principle of sensing is based on the variation of conductivity resulting from a disturbance of charge on the surface of the SiNW–FET. In this study, we have used two different processes for surface modification of silicon nanowire. As the DNA of liver cancer cells has mutation at codon 249 which changes one base guanine (G) by base thymine (T), we thus designed 17–mer DNA oligonucleotides, which were used as a receptor to capture the DNA of p53 mutated gene. The fabricated SiNW biosensor could detect DNA of p53 mutated gene with concentrations down to about 100 pM.

In this paper, Pt nanoparticles were successfully prepared by modified polyol method using silver nitrate as an effective structure-modifying agent. The characterization of Pt nanoparticles was investigated by using UV-Vis-NIR spectroscopy, transmission electron microscopy (TEM) and high resolution (HR) TEM, and x-ray diffraction (XRD). The method of selected area electron diffraction (SEAD) was used to study the structure of Pt nanoparticles. The results showed that the as-prepared Pt nanoparticles exhibiting the complexity of surface structure and morphology could be used as efficient catalysts for polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs).

This work presents the results of the successful preparation of Pd nanoparticles by the polyol method and the proposed techniques of controlling their size and shape. Polyvinylpyrrolidone (PVP) stabilized Pd nanoparticles of various shapes with the largest sizes in the forms of octahedrons (24 nm), tetrahedrons (22 nm) and cubes (20 nm) have been obtained by alcohol reduction in ethanol with the addition of a hydrochloric acid catalyst. Moreover, PVP–Pd nanoparticles of well-controlled spherical shapes have also been prepared by a modified polyol method. PVP–Pd nanoparticles of cubic, octahedral, tetrahedral and spherical shapes with well-controlled size achieved by using ethylene glycol (EG) as reductant and various inorganic species were also fabricated. In particular, Pd nanorods with sizes of 47 nm and 16 nm formed due to the anisotropic growth mechanism of Pd nanoparticles were found. At the same time, tetrahedral particles of sharp shapes of 120 nm and 70 nm sizes have been observed. A high concentration of inorganic species was used to control the size and shape of the Pd nanoparticles, leading to the appearance of various irregular sizes and shapes. There was evidence of the very sharp corners and edges of tetrahedral and octahedral Pd nanoparticles or others that were formed in the clustering and combination of the seeds of smaller particles.