Numerical Analysis of the Temperature Field in Luminaires

This paper contains a calculation of the thermal field caused by electro-heat in lighting devices. After specifying the heat sources, a thermal analysis is make using the finite element method and the equivalent thermal scheme method. The calculated results have been verified experimentally

Electro-thermo-mechanical analysis of actuator structure made of functionally graded material.

The paper deals with a new approach in analyzing of the actuator systems made of Functionally Graded Materials (FGM) using our new beam finite elements. Weak coupled electro-thermomechanical analysis and spatial continuous variation of material properties are considered for chosen actuator structure. This electrically driven actuator is simple-shaped due to properly chosen variation of material properties to ensure functionality of the actuator at material and physical level instead of the geometric shape level. The solution results will be compared with those obtained by using solid elements of a FEM commercial program

Rotation of the flap controlled by the air flow from the fan – educational mechatronic system

This work was supported by the Slovak Grant Agency: KEGA 006STU-4/2023, VEGA 1/0416/21, and APVV-19-0406. This article was also created thanks to support under the Operational Program Integrated Infrastructure for the project: National Infrastructure for Supporting Technology Transfer in Slovakia II – NITT SK II, co-financed by the European Regional Development Fund

Calculation of the stresses in the tapered FGM beams with varying stiffness

The authors gratefully acknowledge financial support by the Slovak Grant Agency of the project VEGA No. 1/0416/21 and by the Slovak Research and Development Agency under Contract no. APVV-19-0406

Device for measuring the stiffness of the tensile nylon springs

This work was supported by the Slovak Research and Development Agency under the contract No. APVV-19-0406, by Grant Agency VEGA, grant No. 1/0416/21 and by Grant Agency KEGA, grant No. 011STU-4/2020

Actuator structure analysis using new electro-thermo-mechanical finite element for functionally graded materials.

Proposed paper deals with electro-thermo-mechanical analysis of chosen actuator structure made od FGM using new finite element derived specially for this purpose. Rectangular cross-section of individual beams that form the von Mises structure with variation of material properties in longitudinal and lateral direction will be considered. Actuator action, electric voltage and temperature peak and also mechanical stress of the structure will be evaluated. Results from the analysis calculated using our new FGM beam finite elements will be compared to results from conventional FEM analysis where standard finite elements will be used

Kinematic and constitutive equations in warping torsion of FGMs beams with spatially varying material properties

The authors gratefully acknowledge financial support by the Slovak Grant Agency of the project VEGA No. 1/0416/21 and by the Slovak Research and Development Agency under Contract no. APVV-19-040

A Search for Selectrons and Squarks at HERA

Data from electron-proton collisions at a center-of-mass energy of 300 GeV are used for a search for selectrons and squarks within the framework of the minimal supersymmetric model. The decays of selectrons and squarks into the lightest supersymmetric particle lead to final states with an electron and hadrons accompanied by large missing energy and transverse momentum. No signal is found and new bounds on the existence of these particles are derived. At 95% confidence level the excluded region extends to 65 GeV for selectron and squark masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure

Search for Doubly-Charged Higgs Boson Production at HERA

A search for the single production of doubly-charged Higgs bosons H^{\pm \pm} in ep collisions is presented. The signal is searched for via the Higgs decays into a high mass pair of same charge leptons, one of them being an electron. The analysis uses up to 118 pb^{-1} of ep data collected by the H1 experiment at HERA. No evidence for doubly-charged Higgs production is observed and mass dependent upper limits are derived on the Yukawa couplings h_{el} of the Higgs boson to an electron-lepton pair. Assuming that the doubly-charged Higgs only decays into an electron and a muon via a coupling of electromagnetic strength h_{e \mu} = \sqrt{4 \pi \alpha_{em}} = 0.3, a lower limit of 141 GeV on the H^{\pm\pm} mass is obtained at the 95% confidence level. For a doubly-charged Higgs decaying only into an electron and a tau and a coupling h_{e\tau} = 0.3, masses below 112 GeV are ruled out.Comment: 15 pages, 3 figures, 1 tabl