Search results for "LIMIT"
showing 10 items of 2826 documents
Controllable Solid Rocket Motor Nozzle Operations in Conditions of Limited-Amplitude Fluctuations
2009
A nonlinear multi scale analysis of a controllable solid rocket motor operating in conditions ranging from high-amplitude fluctuations in combustion chamber to conditions lying in limit cycle is presented and the motor behavior subsequent to some relevant nozzle operations is investigated. Effects of acoustic-vorticity-entropy wave coupling, wave steepening, rotational/viscous flow losses, steep-fronted wave losses are taken into account and oscillatory energy losses in pintle-nozzle, unsteady combustion and chamber geometry changes resulting from grain regression are included. The analysis provides evidence that the unsteady energy balance and the motor wave amplitude evolution are influen…
Fronts propagating with signal dependent speed in limited diffusion and related Hamilton-Jacobi formulations
2021
We consider a class of limited diffusion equations and explore the formation of diffusion fronts as the result of a combination of diffusive and hyperbolic transport. We analyze a new class of Hamilton-Jacobi equations arising from the convective part of general Fokker-Planck equations ruled by a non-negative diffusion coefficient that depends on the unknown and on the gradient of the unknown. We explore the main features of the solution of the Hamilton-Jacobi equations that contain shocks and propose a suitable numerical scheme that approximates the solution in a consistent way with respect to the solution of the associated Fokker-Planck equation. We analyze three model problems covering d…
Locally Convex *-Algebras and the Thermodynamical Limit of Quantum Models
2000
We show that the thermodynamical limit of several physical models is naturally obtained within the framework of topological quasi *-algebras. In particular, the relevance of the algebra L + (D) is shown explicitly by concrete examples.
Direct Instruction vs. Cooperative Learning in Physical Education: Effects on Student Learning, Behaviors, and Subjective Experience
2020
(1) Background: The objective was to analyze if cooperative learning (CL) can have benefits compared to direct instruction (DI) in learning, behavior, and subjective experience of pupils. (2) Methods: An intervention was performed with a counterbalanced within-subjects design. To perform the intervention, 75 schoolchildren aged 10 to 12 from four primary classes were divided into two groups, and two units were taught in each one, namely &ldquo
Insights into food system exposure, coping capacity and adaptive capacity
2017
Purpose The purpose of this paper is to consider the concepts of exposure, coping capacity and adaptive capacity as a multiple structure of vulnerability in order to distinguish and interpret short-term coping responses and long-term strategic responses to food system vulnerability. Design/methodology/approach This paper applies an abductive approach for qualitative analysis of data, which were collected through 18 semi-structured interviews among Finnish food system actors. Findings The findings suggest that coping capacity and adaptive capacity are indeed two different concepts, which both need to be addressed in the examination of food system vulnerability. Public and private food syste…
A note on correlation and local dimensions
2015
Abstract Under very mild assumptions, we give formulas for the correlation and local dimensions of measures on the limit set of a Moran construction by means of the data used to construct the set.
The transient gravitational-wave sky
2013
Interferometric detectors will very soon give us an unprecedented view of the gravitational-wave sky, and in particular of the explosive and transient Universe. Now is the time to challenge our theoretical understanding of short-duration gravitational-wave signatures from cataclysmic events, their connection to more traditional electromagnetic and particle astrophysics, and the data analysis techniques that will make the observations a reality. This paper summarizes the state of the art, future science opportunities, and current challenges in understanding gravitational-wave transients.
Effects of an Individualized Active Aging Counseling Intervention on Mobility and Physical Activity: Secondary Analyses of a Randomized Controlled Tr…
2020
Objectives: The aim of this study was to report preplanned secondary analyses of the effects of a 12-month individualized active aging counseling intervention on six mobility and physical activity outcomes. Methods: A two-arm, single-blinded randomized controlled trial was conducted among 75- and 80-year-old community-dwelling people. The intervention group (IG, n = 101) received counseling aimed at increasing self-selected, primarily out-of-home activity. The control group (CG, n = 103) received general health information. Data were analyzed with generalized estimating equations. Results: Physical performance improved in the IG more than that in the CG (group by time p = .022), self-repor…
A tailored counseling and home-based rehabilitation program to increase physical activity and improve mobility among community-dwelling older people …
2017
Physical activity (PA) decreases during hospitalization. In particular, the amount of PA engaged in by older people who are hospitalized following musculoskeletal injury is likely to be limited for months after discharge home. Given the importance of an active lifestyle for their recovery and the prevention of future adverse outcomes, there is clearly a need for interventions to increase PA. This article describes the protocol of a randomized controlled trial set up to investigate the effects of a physical activity oriented home rehabilitation program (ProPA) on PA and the restoration of mobility in community-dwelling older people. Men and women aged 60 years or older hospitalized due to a …
Effects of comprehensive geriatric assessment and targeted intervention on mobility in persons aged 75 years and over: a randomized controlled trial
2011
Objective: To assess the effect of a comprehensive geriatric assessment and individually tailored intervention on mobility in older people. In addition, the effectiveness of the geriatric intervention was evaluated among a subgroup of persons with musculoskeletal pain. Design: Three-year geriatric development project with randomized assignment to intervention and control group. Setting: Research centre, community and assisted living facilities. Participants: Seven hundred and eighty-one Finnish persons aged 75–98 years were assigned to an intervention ( n = 404) or control ( n = 377) group. Intervention: A comprehensive geriatric assessment with a multifactorial intervention lasting two ye…