Dynamics of Flexible Spinning Satellites with Radial Wire Antennas

A dynamic analysis is presented for a spin stabilized spacecraft employing four radial wire antennas with tip masses, a configuration first employed in the IMP-J spacecraft. The use of wires in place of the usual booms represents the ultimate in weight reduction at the expanse of flexibility. The satellite is modelled as a 14 degree of freedom system, and the linearized equations of motion are found. The lowest order vibrational modes and natural frequencies of the gyroscopically coupled system are then determined. Because the satellite spin rate is decreased by antenna deployment, a spin-up maneuver is needed. The response of the time varying mode equations during spin-up is found, for the planar modes, in terms of Bessel functions and a Struve function of order -1/4. Because tables of the latter are not readily available, the particular solution is expressed in various forms including an infinite series of Bessel functions and a particularly useful asymptotic expansion

A fiatalok családalapítási mintázata

Hazánk demográfiai jellemzőinek vizsgálatakor több radikális változás figyelhető meg.Egyrészt 1990-től kezdődően csökkent a házasságkötések száma, valamint nőtt az egyedülállók, elváltak népességen belüli aránya. Kitolódott a házasságkötések és agyermekvállalás életkora, lecsökkent a gyermekszületések száma. Írásunkban a nyíregyházi fiatalok (15-29 év) párválasztásához, gyermekvállaláshoz fűződő attitűdjét térképeztük fel, adatainkat összevetettük a hazai ifjúságkutatások eredményeivel. (Jelen írásunk R. Fedor, A. (2016): Családalapítás és gyermekvállalás a fiatalok körében című, az Acta Medicinae et sociologica 7 (20-21). 11-2. számában megjelent tanulmányának átdolgozott rövidített változata.) Vizsgálatunk eredményei egy határozottan gyermekcentrikus és házasságpárti helyi fiatal társadalom jelenlétéről árulkodnak. Eredményeink szerint a többség a kétgyermekes családmodellt preferálja. Kevesen, a válaszadók mindössze 5%-a nem szeretne gyermeket vállalni. A jelenleg független fiatalok meghatározó többsége házasként képzeli el a jövőjét

To study the influence of snow cover on the power generated by photovoltaic modules

The possibility of increasing the power generation of PV modules due to radiation reflected from the snow is investigated. An experiment has been held to determine the value of the current generated by PV-modules on account of the underlying snow surface. Also the experiment has been held to determine the influence of the PV-module's location due the snow surface on the performance of solar cells

Mechanisms and dynamics of the metastable decay in Ar-2(+)

A detailed experimental as well as theoretical investigation of the properties of the metastable dissociation Ar-2(+)--\u3eAr++Ar is presented. The mass-analyzed ion kinetic energy (MIKE) scan technique has been performed using a three sector field mass spectrometer. The possible mechanisms of the metastability of Ar-2(+) have been examined and the observed decay process is assigned to the II(1/2)(u)--\u3eI(1/2)(g) bound to continuum radiative transition, in agreement with earlier work. The calculation of the theoretical shape of the kinetic energy release distribution of fragment ions allowed us to construct the theoretical MIKE peak and compare it with the raw experimental data. The accuracy of various sets of potential energy curves for Ar-2(+) is discussed, as well as the way of production of the metastable Ar-2(+)[II(1/2)(u)] electronic state by electron impact. Excellent agreement between the experimental data and theoretical model has been observed. (C) 2004 American Institute of Physics

Clock transition by continuous dynamical decoupling of a three-level system

We present a novel continuous dynamical decoupling scheme for the construction of a robust qubit in a three-level system. By means of a clock transition adjustment, we first show how robustness to environmental noise is achieved, while eliminating drive-noise, to first-order. We demonstrate this scheme with the spin sub-levels of the NV-centre's electronic ground state. By applying drive fields with moderate Rabi frequencies, the drive noise is eliminated and an improvement of 2 orders of magnitude in the coherence time is obtained compared to the pure dephasing time. We then show how the clock transition adjustment can be tuned to eliminate also the second-order effect of the environmental noise with moderate drive fields. A further improvement of more than 1 order of magnitude in the coherence time is expected and confirmed by simulations. Hence, our scheme prolongs the coherence time towards the lifetime-limit using a relatively simple experimental setup.Comment: 7 pages, 5 figure

The Phenomenon and the Characteristics of Precariate in Hungary: Labormarket situation, Precariate, Subjective health

[EN] The paper introduces the labor-market characteristics of 18-70 year-old age group in Nyíregyháza in Hungary. The focus of our research is labor market integration and the related issues like family formation, work attitudes and subjective health status. The theoretical background of this analytical work is based on precariate, a social phenomenon that has not been used widespreadly yet. This study defines precarity as a labour-market uncertainty which includes insecure short-term jobs, fixed-term employment contracts, and lower positions in the labor-market hierarchy. Our main research question is: Is there relevance between the phenomenon of precariate and labor market disadvantage and subjective health status? Our results show a significant correlation between the variables (phenomenon of precariate, labor market situation and subjective health status).Fedor, ARF.; Erdei, R. (2019). The Phenomenon and the Characteristics of Precariate in Hungary: Labormarket situation, Precariate, Subjective health. En Proceedings 5th CARPE Conference: Horizon Europe and beyond. Editorial Universitat Politècnica de València. 252-257. https://doi.org/10.4995/CARPE2019.2019.10284OCS25225