The Discrete Planar Cosserat Rod and its Stability Analysis

In this paper a discrete model of the planar Cosserat rod is studied. The equilibrium equations, the stability matrix, and the buckling loads of the model are presented in a dimensionless form for axial loading, pinned ends, and linear elasticity. Numerical simulations are accomplished and bifurcation diagrams of a short chain are shown for large displacements and various stiffness values

Susceptibility to addictive behaviour in online and traditional poker playing environments

Abstract Background and aims: With the growing number of virtual sites and easy access to them, as well as increasing popularity of the game, online poker could foster addiction. The aim of the current inquiry was to gauge susceptibility to behavioural addiction in online and traditional poker players. Methods: Ninety-six online poker players and 35 traditional players were tested on the basis of the “Components model” for addiction (Griffiths, 2005). Using a Likert scale, ratings on six components were examined: salience, conflict, mood modification, withdrawal symptoms, tolerance, and relapse. Results: The traditional players scored higher than online players on measures of conflict, mood modification, and relapse. While none of the traditional players were at risk, the majority of them (94.7%) were symptomatic. Two online players were at risk, 67.7% symptomatic and 30.2% asymptomatic. No significant correlations have emerged between the amount and history of poker playing and the addiction scores. Conclusions: The current findings suggest that most traditional players are prone to behavioural addiction while the majority of the online players are also symptomatic

DEVELOPMENT TRENDS AND RESULTS IN SPINAL TESTS

Spinal tests have been performed by an ultrasound-based movement test system at the Biomechanical Laboratory of the Department of Applied Mechanics of the Budapest University of Technology and Economics for several years. The system is suitable for rapid tests of the mobility, structure, and deformations of the spine, screening tests, and monitoring. Tests and evaluation take a short time: a complete screening test takes 20 to 25 minutes, a simplified test about 5 minutes. Besides its numerous advantages, it should be noted that the total cost of installing the system - equipment, software, hardware - is only about 8000 EUR. This article presents the structure and use of a modern ultrasound-based system as well as the results of our investigations

Hypertension and Sleep Apnea

Diagnosis and treatment of comorbid conditions in hypertension are essential for efficient blood pressure control and for decreasing adverse clinical events and mortality. Sleep apnea, mainly its obstructive form, has a high prevalence both in the general population and in hypertensive patients, the main reason being the worldwide epidemic of obesity. This chapter summarizes the principal issues related to hypertension-sleep apnea relationship: definition of terms, epidemiological data and evidences, clinical manifestations of sleep apnea, pathophysiological background of the adverse effects of sleep apnea on the cardiovascular system, screening and definitive diagnosis, and the effects of specific and nonspecific sleep apnea interventions on hypertension

BUCKLING UNDER NONCONSERVATIVE LOAD: CONSERVATIVE SPATIAL CHAOS

Buckling of an elastic linkage under nonconservative load is investigated. There is a related initial value problem, which is conservative and chaotic, and gives valuable aid in finding the buckled shapes of the linkage. To illustrate the equilibrium configurations, the bifurcation diagram is constructed, which turns out to be a distorted version of the bifurcation diagram of the linkage under a conservative load

Csigasorral függesztett gerenda szabadrezgése modálanalízissel

Egy csigasorral függesztett gerenda szabadrezgését vizsgáljuk. A gerendát Bernoulli-Euler rúdként modellezzük, és bemutatjuk a szerkezet sajátrezgésalakjait és sajátkörfrekvenciáit feszített és feszítetlen függesztőkábel esetén a folytonos rúd differenciálegyenletének megoldásával. A kábel feszített, vagy feszítetlen voltától függ ̋oen beszélünk aktív és passzív függesztésr ̋ol. Az aktív és passzív függesztés rezgésalakjai egymásnak megfeleltethet ̋oek, az állapotváltozások során a modális koordináták transzformációja id ̋ofüggetlen módon végezhető. Numerikus módszert mutatunk a rezgés számítására, az aktív és passzív állapotok közötti váltás kezelésére. Különböző kezdőállapotokat használva szimuláljuk a tartó szabadrezgését. Megmutatjuk, hogy még az aktív és passzív függesztések közötti váltás okozta erős nemlinearitás mellett is képes a szerkezet periodikus szabadrezgést végezni

A barátság történeti és szociológiai aspektusai

Recenzió: Albert Fruzsina – Dávid Beáta. Embert barátjáról – A barátság szociológiája. Századvég Kiadó, Budapest, 2007

Új jóléti paradigma felé?

Recenzió: Nyilas Mihály [szerk.]: A jóléti állam a 21. században. Hilscher Rezső Szociálpolitikai Egyesület – ELTE TáTK Szociális Munka és Szociálpolitikai Tanszék, Budapest, 2009

Szomorú látlelet a magyarországi cigányság helyzetéről

Recenzió: Törzsök Erika – Paskó Ildi – Zolnay János [szerk.]: Cigánynak lenni Magyarországon – Jelentés 2006: A romapolitika kifulladása. EÖKIK, Budapest, 2007