Excavator Wheel Drive Reconstruction.

Import 05/08/2014V této práci je popsán pomocný pohon kolesa rypadla a možnost jeho rozběhu softstartérem a frekvenčním měničem. V první části je probrán asynchronní motor s kotvou nakrátko, jeho popis a princip funkce. Další části se věnují softstartéru a frekvenčnímu měniči, jejich popisu, funkcím a možnostem řízení. Dále je zde provedeno měření jejich vlivu na síť. Poslední část je věnována návrhu rekonstrukce pohonu pro napájení s frekvenčním měničem.This thesis describes the auxiliary drive wheel excavators and the possibility of starting the softstarter and frequency converter. In the first part of the document the asynchronous motor with squirrel cage is discussed, its description and function. Other parts of the document are devoted to the soft starter and frequency converter, their description, function and management options. Furthermore, there is performed measurement of their effect on the network. The last section is devoted to the design of the reconstruction drive with the frequency converter.410 - Katedra elektroenergetikyvýborn

Measurement of D* Meson Cross Sections at HERA and Determination of the Gluon Density in the Proton using NLO QCD

With the H1 detector at the ep collider HERA, D* meson production cross sections have been measured in deep inelastic scattering with four-momentum transfers Q^2>2 GeV2 and in photoproduction at energies around W(gamma p)~ 88 GeV and 194 GeV. Next-to-Leading Order QCD calculations are found to describe the differential cross sections within theoretical and experimental uncertainties. Using these calculations, the NLO gluon momentum distribution in the proton, x_g g(x_g), has been extracted in the momentum fraction range 7.5x10^{-4}< x_g <4x10^{-2} at average scales mu^2 =25 to 50 GeV2. The gluon momentum fraction x_g has been obtained from the measured kinematics of the scattered electron and the D* meson in the final state. The results compare well with the gluon distribution obtained from the analysis of scaling violations of the proton structure function F_2.Comment: 27 pages, 9 figures, 2 tables, submitted to Nucl. Phys.

New System for the Acceleration of the Airflow in Wind Turbines

Background: This patent is based on the wind industry technology called Diffuser Augmented Wind Turbines (DAWTs). This technology consists of a horizontal axis wind turbine, which is housed inside a duct with diverging section in the direction of the free air stream. In this paper, a review of preceding patents related to this technology is carried out. Objective: This paper presents an innovative patent to improve the performance of horizontal axis wind turbines. In particular, this system is aimed at improving the performance of those turbines that otherwise might not be installed due to the low wind resource existing at certain locations. Methods: The most innovative elements of this patent are: (1) the semi-spherical grooves, which are mechanized on the surface of the two diffusers in order to guarantee a more energetic boundary layer; (2) the coaxial diffuser, which is located downwind following the first diffuser in order to increase the suction effect on the air mass close to the inlet; (3) the coaxial rings located around the first diffuser outlet, which are used to deflect the external airflow toward the turbine wake; and (4), the selforientating system to orientate the system by the prevailing wind direction. Results: An application of the patent for increasing the power generated by a horizontal axis wind turbine with three blades is presented. The patent is designed and its performance is evaluated by using a Computational Fluid Dynamics code. The numerical results show that this system rises the airflow going through the rotor of the turbine. Conclusion: The patented device is an original contribution aimed at enabling a more profitable installation of wind turbines in places where the wind resource is insufficient because of the wind shear caused both by the proximity of the earth and the obstacles on the earth surface.This work was supported by the OASIS Research Project that was cofinanced by CDTI (Spanish Science and Innovation Ministry) and developed with the Spanish companies: Iridium, OHL Concesiones, Abertis, Sice, Indra, Dragados, OHL, Geocisa, GMV, Asfaltos Augusta, Hidrofersa, Eipsa, PyG, CPS, AEC and Torre de Comares Arquitectos S.L and 16 research centres. The authors also acknowledge the partial funding with FEDER funds under the Research Project FC-15-GRUPIN14-004. Finally, we also thank Swanson Analysis Inc. for the use of ANSYS University Research programs as well as the Workbench simulation environment

Charmonium Production in Deep Inelastic Scattering at HERA

The electroproduction of J/psi and psi(2S) mesons is studied in elastic, quasi-elastic and inclusive reactions for four momentum transfers 2 Q^2 80 GeV^2 and photon-proton centre of mass energies 25 W 180 GeV. The data were taken with the H1 detector at the electron proton collider HERA in the years 1995 to 1997. The total virtual photon-proton cross section for elastic J/psi production is measured as a function of Q^2 and W. The dependence of the production rates on the square of the momentum transfer from the proton (t) is extracted. Decay angular distributions are analysed and the ratio of the longitudinal and transverse cross sections is derived. The ratio of the cross sections for quasi-elastic psi(2S) and J/psi meson production is measured as a function of Q^2. The results are discussed in terms of theoretical models based upon perturbative QCD. Differential cross sections for inclusive and inelastic production of J/psi mesons are determined and predictions within two theoretical frameworks are compared with the data, the non-relativistic QCD factorization approach including colour octet and colour singlet contributions, and the model of Soft Colour Interactions

Protocol for a partially nested randomised controlled trial to evaluate the effectiveness of the scleroderma patient-centered intervention network COVID-19 home-isolation activities together (SPIN-CHAT) program to reduce anxiety among at-risk scleroderma patients

Objective: Contagious disease outbreaks and related restrictions can lead to negative psychological outcomes, particularly in vulnerable populations at risk due to pre-existing medical conditions. No randomised controlled trials (RCTs) have tested interventions to reduce mental health consequences of contagious disease outbreaks. The primary objective of the Scleroderma Patient-centered Intervention Network COVID-19 Home-isolation Activities Together (SPIN-CHAT) Trial is to evaluate the effect of a videoconference-based program on symptoms of anxiety. Secondary objectives include evaluating effects on symptoms of depression, stress, loneliness, boredom, physical activity, and social interaction.Methods: The SPIN-CHAT Trial is a pragmatic RCT that will be conducted using the SPIN-COVID-19 Cohort, a sub-cohort of the SPIN Cohort. Eligible participants will be SPIN-COVID-19 Cohort participants without a positive COVID-19 test, with at least mild anxiety (PROMIS Anxiety 4a v1.0 T-score >= 55), not working from home, and not receiving current counselling or psychotherapy. We will randomly assign 162 participants to intervention groups of 7 to 10 participants each or waitlist control. We will use a partially nested RCT design to reflect dependence between individuals in training groups but not in the waitlist control. The SPIN-CHAT Program includes activity engagement, education on strategies to support mental health, and mutual participant support. Intervention participants will receive the 4-week (3 sessions per week) SPIN-CHAT Program via video-conference. The primary outcome is PROMIS Anxiety 4a score immediately post-intervention.Ethics and dissemination: The SPIN-CHAT Trial will test whether a brief videoconference-based intervention will improve mental health outcomes among at-risk individuals during contagious disease outbreak

A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

The Scleroderma Patient-Centered Intervention Network Self-Management Program: Protocol for a randomized feasibility trial

Contains fulltext : 219726.pdf (publisher's version ) (Open Access)Background: Systemic sclerosis (SSc), or scleroderma, is a rare disease that often results in significant disruptions to activities of daily living and can negatively affect physical and psychological well-being. Because there is no known cure, SSc treatment focuses on reducing symptoms and disability and improving health-related quality of life (HRQoL). Self-management programs are known to increase self-efficacy for disease management in many chronic diseases. The Scleroderma Patient-centered Intervention Network (SPIN) developed a Web-based self-management program (SPIN self-management; SPIN-SELF) to increase self-efficacy for disease management and to improve HRQoL for patients with SSc. Objective: The proposed study aims to assess the feasibility of conducting a full-scale randomized controlled trial (RCT) of the SPIN-SELF program by evaluating the trial implementation processes, required resources and management, scientific aspects, and participant acceptability and usage of the SPIN-SELF program. Methods: The SPIN-SELF feasibility trial will be conducted via the SPIN Cohort. The SPIN Cohort was developed as a framework for embedded pragmatic trials using the cohort multiple RCT design. In total, 40 English-speaking SPIN Cohort participants with low disease management self-efficacy (Self-Efficacy for Managing Chronic Disease Scale score ≤7), who have indicated interest in using a Web-based self-management program, will be randomized with a 3:2 ratio into the SPIN-SELF program or usual care for 3 months. Feasibility outcomes include trial implementation processes, required resources and management, scientific aspects, and patient acceptability and usage of the SPIN-SELF program. Results: Enrollment of the 40 participants occurred between July 5, 2019, and July 27, 2019. By November 25, 2019, data collection of trial outcomes was completed. Data analysis is underway, and results are expected to be published in 2020. Conclusions: The SPIN-SELF program is a self-help tool that may improve disease-management self-efficacy and improve HRQoL in patients with SSc. The SPIN-SELF feasibility trial will ensure that trial methodology is robust, feasible, and consistent with trial participant expectations. The results will guide adjustments that need to be implemented before undertaking a full-scale RCT of the SPIN-SELF program. International Registered Report Identifier (IRRID): DERR1-10.2196/1679915 p