100 research outputs found

    A Novel Broadband Printed Dipole Antenna and Its Application for TD-LTE Communications

    Get PDF
    Novel double-sided printed dipole antennas are proposed and investigated in this paper. Two pairs of identical T-shape metallic loadings are connected to the traditional double-sided printed dipole, enhancing the operating bandwidth. Simulations show that the proposed printed dipole without the reflecting ground plane gives a bandwidth of up to 90.7% for S11<-10 dB or 84.9% for S11<-15 dB, which is significantly greater than those of the traditional printed dipole. The proposed dipole is then applied to design a dual-polarized printed dipole antenna, mounted on a ground plane. Measurements for the prototype show a bandwidth of 68.8% for S11<-10 dB, covering the entire TD-LTE band. The gain is about 6–8 dBi and the isolation is over 24 dB over the bandwidth

    A Novel Broadband Printed Dipole Antenna and Its Application for TD-LTE Communications

    Get PDF
    Novel double-sided printed dipole antennas are proposed and investigated in this paper. Two pairs of identical T-shape metallic loadings are connected to the traditional double-sided printed dipole, enhancing the operating bandwidth. Simulations show that the proposed printed dipole without the reflecting ground plane gives a bandwidth of up to 90.7% for 11 &lt; −10 dB or 84.9% for 11 &lt; −15 dB, which is significantly greater than those of the traditional printed dipole. The proposed dipole is then applied to design a dual-polarized printed dipole antenna, mounted on a ground plane. Measurements for the prototype show a bandwidth of 68.8% for 11 &lt; −10 dB, covering the entire TD-LTE band. The gain is about 6-8 dBi and the isolation is over 24 dB over the bandwidth

    Chlorido[4-chloro-2-(pyridin-2-yl­methyl­imino­meth­yl)phenolato-κ3 N,N′,O]copper(II)

    Get PDF
    In the title complex, [Cu(C13H10ClN2O)Cl], the CuII ion is coordinated by one O atom and two N atoms of the tridentate Schiff base ligand and one chloride ion, forming a slightly distorted square-planar geometry. Weak Cu⋯Cl inter­actions [2.793 (5) Å] result in the formation of a chain along the a axis

    Bis(2,2′-bipyridyl-κ2 N,N′)bis­(dicyanamido-κN)manganese(II)

    Get PDF
    In title complex, [Mn(C2N3)2(C10H8N2)2], the MnII ion is coordinated in a slightly distorted octa­hedral geometry by six N atoms. Four of the N atoms are from two chelating bipyridine ligands and two are from a pair of cis-coordinated dicyanamide ligands. The dihedral angle formed by the mean planes of the bipyridine rings is 85.93 (14)°. The central N atom of one of the dicyanamide ligands was refined as disordered over two sites with equal occupancies

    Investigation of heat flux deposition on divertor target on the Large Helical Device with EMC3-EIRENE modelling

    Get PDF
    The measured divertor heat flux profiles are compared to the EMC3-EIRENE simulations for two different times of an LHD discharge, corresponding to higher and lower edge temperatures. The relation between the three-dimensional magnetic field structure and the heat flux distributions on the divertor has been analysed. The modelled heat flux for the lower plasma temperature case has a better agreement with the experimental result obtained by the Langmuir probes, which shows a qualitative reproduction of the experimental profile shape. However, the heat flux distribution for the high plasma temperature case shows a different behaviour between the simulation results and the experimental measurements. The detailed analysis of the heat flux distribution for the higher temperature case which has a larger discrepancy has been performed, both quantitatively and qualitatively. The radiation of the eroded impurity from divertor target plates has a minor effect on the heat flux distribution. Non-uniform cross-field transport coefficients are used in the simulations and its impact on the heat flux distributions is discussed for the case of the high plasma temperature

    Model based dynamic analysis of human sleep electroencephalogram

    Full text link
    For sleep classification, automatic electroencephalogram (EEG) interpretation techniques are of interest because they are labour saving, in contrast to manual (visual) methods. More importantly, some automatic methods, which offer a less subjective approach, can provide additional information which it is not possible to obtain by manual analysis.;An extensive literature review has been undertaken to investigate the background of automatic EEG analysis techniques. Frequency domain and time domain methods are considered and their limitations are summarised. The weakness in the R & K rules for visual classification and from which most of the automatic systems borrow heavily are discussed.;A new technique - model based dynamic analysis - was developed in an attempt to classify the sleep EEG automatically. The technique comprises of two phases, these are the modelling of EEG signals and the analysis of the model's coefficients using dynamic systems theory. Three techniques of modelling EEG signals are compared: the implementation of the non-linear prediction technique of Schaffer and Tidd (1990) based on chaos theory; Kalman filters and a recursive version of a radial basis function for modelling and forecasting the EEG signals during sleep. The Kalman filter approach produced good results and this approach was used in an attempt to classify the EEG automatically. For classifying the model's (Kalman filter's) coefficients, a new technique was developed by a state-space approach. A 'state variable' was defined based on the state changes of the EEG and was shown to be correlated with the depth of sleep. Furthermore it is shown that this technique may be useful for automatic sleep staging. Possible applications include automatic staging of sleep, detection of micro-arousals, anaesthesia monitoring and monitoring the alertness of workers in sensitive or potentially dangerous environments

    Functionalized carbon nanotubes and nanofibers for biosensing applications

    No full text
    This review summarizes recent advances in electrochemical biosensors based on carbon nanotubes (CNTs) and carbon nanofibers (CNFs) with an emphasis on applications of CNTs. CNTs and CNFs have unique electric, electrocatalytic and mechanical properties, which make them efficient materials for developing electrochemical biosensors.We discuss functionalizing CNTs for biosensors. We review electrochemical biosensors based on CNTs and their various applications (e.g., measurement of small biological molecules and environmental pollutants, detection of DNA, and immunosensing of disease biomarkers). Moreover, we outline the development of electrochemical biosensors based on CNFs and their applications. Finally, we discuss some future applications of CNTs

    Spacecraft Multiple-Impulse Trajectory Optimization Using Differential Evolution Algorithm with Combined Mutation Strategies and Boundary-Handling Schemes

    Get PDF
    Since most spacecraft multiple-impulse trajectory optimization problems are complex multimodal problems with boundary constraint, finding the global optimal solution based on the traditional differential evolution (DE) algorithms becomes so difficult due to the deception of many local optima and the probable existence of a bias towards suboptimal solution. In order to overcome this issue and enhance the global searching ability, an improved DE algorithm with combined mutation strategies and boundary-handling schemes is proposed. In the first stage, multiple mutation strategies are utilized, and each strategy creates a mutant vector. In the second stage, multiple boundary-handling schemes are used to simultaneously address the same infeasible trial vector. Two typical spacecraft multiple-impulse trajectory optimization problems are studied and optimized using the proposed DE method. The experimental results demonstrate that the proposed DE method efficiently overcomes the problem created by the convergence to a local optimum and obtains the global optimum with a higher reliability and convergence rate compared with some other popular evolutionary methods
    • …
    corecore