Datalogger for UL aircraft

Diplomová práce se zabývá návrhem zapisovače letových dat pro UL letadla. V teoretické části jsou popsány základní principy měření jednotlivých veličin ve vztahu k provozu letadla, např. výšky, rychlosti. V samostatné kapitole se věnuji systémům pro určení polohy GPS. Dále jsou zde uvedeny příklady přístrojů měřících tyto veličiny. Praktická část je zaměřena na popis vybraných komponent a jejich obsluhu mikrokontrolérem PIC24FJ64GA004. Následuje popis obsluhy USB disků pomocí USB kontroléru Vinculum-II. Práce je zakončena provedením testu funkčnosti zařízení.This thesis describes the design of flight data recorder for UL aircraft. The theoretical part describes the basic principles of measurement of the quantities in relation to the operation of the aircraft, such as altitude, air speed. A separate chapter deals with systems for determining of GPS position. Furthermore, there are examples of instruments measuring these quantities. The practical part is focused on the description of selected components and their connection to PIC24FJ64GA004 microcontroller. This is followed by a description of the control of USB drives with USB Controller Vinculum-II. The work is finished by the functional test of the device.

A Data-Aided Channel Estimation Scheme for Decoupled Systems in Heterogeneous Networks

Uplink/downlink (UL/DL) decoupling promises more flexible cell association and higher throughput in heterogeneous networks (HetNets), however, it hampers the acquisition of DL channel state information (CSI) in time-division-duplex (TDD) systems due to different base stations (BSs) connected in UL/DL. In this paper, we propose a novel data-aided (DA) channel estimation scheme to address this problem by utilizing decoded UL data to exploit CSI from received UL data signal in decoupled HetNets where a massive multiple-input multiple-output BS and dense small cell BSs are deployed. We analytically estimate BER performance of UL decoded data, which are used to derive an approximated normalized mean square error (NMSE) expression of the DA minimum mean square error (MMSE) estimator. Compared with the conventional least square (LS) and MMSE, it is shown that NMSE performances of all estimators are determined by their signal-to-noise ratio (SNR)-like terms and there is an increment consisting of UL data power, UL data length and BER values in the SNR-like term of DA method, which suggests DA method outperforms the conventional ones in any scenarios. Higher UL data power, longer UL data length and better BER performance lead to more accurate estimated channels with DA method. Numerical results verify that the analytical BER and NMSE results are close to the simulated ones and a remarkable gain in both NMSE and DL rate can be achieved by DA method in multiple scenarios with different modulations

Nucleon Transversity Distribution from Azimuthal Spin Asymmetry in Pion Electroproduction

The azimuthal asymmetry observed by the HERMES collaboration in semi-inclusive pion production in deep inelastic scattering of unpolarized positron on the longitudinally polarized proton target, can provide information of the quark transversity distributions of the nucleon. We show that the quark transversity distributions predicted both by the light-cone quark-spectator-diquark model and by a pQCD inspired model can give consistent descriptions of the available HERMES data for the analyzing powers $A_{UL}^{\sin \phi}$ and $A_{UL}^{\sin 2 \phi}$ for $\pi^+$ and $\pi^-$ productions. We also show that the two models give similar predictions of $A_{UL}^{\sin \phi}$ for $\pi^+$ production, whereas they give very different predictions of $A_{UL}^{\sin \phi}$ for $\pi^-$ production at large $x$. Further precision measurement of $A_{UL}^{\sin \phi}$ for $\pi^-$ production can provide a decisive test of different models.Comment: 11 latex pages, 1 figure, version to appear in PR

A double-blinded randomised controlled trial exploring the effect of anodal transcranial direct current stimulation and uni-lateral robot therapy for the impaired upper limb in sub-acute and chronic stroke

BACKGROUND:Neurorehabilitation technologies such as robot therapy (RT) and transcranial Direct Current Stimulation (tDCS) can promote upper limb (UL) motor recovery after stroke. OBJECTIVE:To explore the effect of anodal tDCS with uni-lateral and three-dimensional RT for the impaired UL in people with sub-acute and chronic stroke. METHODS:A pilot randomised controlled trial was conducted. Stroke participants had 18 one-hour sessions of RT (Armeo®Spring) over eight weeks during which they received 20 minutes of either real tDCS or sham tDCS during each session. The primary outcome measure was the Fugl-Meyer assessment (FMA) for UL impairments and secondary were: UL function, activities and stroke impact collected at baseline, post-intervention and three-month follow-up. RESULTS:22 participants (12 sub-acute and 10 chronic) completed the trial. No significant difference was found in FMA between the real and sham tDCS groups at post-intervention and follow-up (p = 0.123). A significant ‘time’ x ‘stage of stroke’ was found for FMA (p = 0.016). A higher percentage improvement was noted in UL function, activities and stroke impact in people with sub-acute compared to chronic stroke. CONCLUSIONS:Adding tDCS did not result in an additional effect on UL impairment in stroke. RT may be of more benefit in the sub-acute than chronic phase