Search results for "dynamic resistance"
showing 10 items of 10 documents
Exercise and Recovery Responses of Lymphokines to Heavy Resistance Exercise
2000
To examine the effect of dynamic resistance exercise on the response patterns of lymphokines, 10 strength-trained men (21.7 +- 0.6 y) performed 2 resistance exercise protocols, high force (HF) and high power (HP), of equal total work (HF 5 33.0 +- 2.5 kJ; HP 5 33.3 +- 2.7 kJ) in a randomized order separated by 1 week. Resting blood samples were obtained preexercise and 0 (R-0), 15 (R-15), and 240 (R-240) minutes postexercise. Plasma lactate significantly (p < 0.05) increased from baseline for both protocols; however, concentrations were higher in response to the HF protocol. Plasma interleukin- 2 (IL-2) concentrations were significantly decreased from baseline at R-15 following the HF proto…
Obtaining dynamic Norton parameters of a solar panel from manufacturer data
2016
Photovoltaic arrays have been shown to possess significant influence on the dynamic performance of coupled source-converter-load system while its dynamic resistance is the most important parameter, contributing to the overall system dynamics. In this paper, a method of deriving the parameters of linearized photovoltaic equivalent circuit from manufacturer data is proposed. The approach allows predicting the range of dynamic Norton parameters for the expected irradiation and temperature operation conditions thus defining clear bounds required for robust design of the system controller.
Sailing dinghy hydrodynamic resistance by experimental and numerical assessments
2020
Abstract Hull forms of high-performance sailing dinghies are very interesting for yacht designers. After a long period in which the attention has been focused on one-design boats, in recent years a few exciting restricted classes such as International Moth, International 14′, 18’ Skiff and Class A catamaran become recognized in several countries and led to interesting advances in high-performance yacht design. “1001VELAcup R3” class is two people racing dinghy designed according to a box rule with limitation on LOA and Bmax and total sail area. The boats must be designed and built by students of European Universities and race yearly in Italy. This paper focuses on two best-ranked boats “LED…
The Effect of Taper and Apical Diameter on the Cyclic Fatigue Resistance of Rotary Endodontic Files Using an Experimental Electronic Device
2021
The aim of this study was to analyze the effect of the taper and apical diameter of nickel&ndash
Dynamic $\mathrm{R}_{\mathrm{ON}}$ evaluation of commercial GaN HEMT under different switching and radiation conditions
2019
This paper focus on the study of dynamic resistance $(\mathrm{R}_{\mathrm{dyn}})$ over commercial Gallium Nitride High Electromobility Transistors (GaN HEMTs) devices. The first part shows a study of the main mechanism causing $\mathrm{R}_{\mathrm{dyn}}$ , showing that depending on the structure, stress time, voltage applied and switching conditions, the $\mathrm{R}_{\mathrm{dyn}}$ can suffer a relevant increase. Also, it is demonstrated how the use of soft-switching conditions can alleviate trapping effects. Finally, due to the interest over these devices for future space applications, the effects of gamma radiation over the $\mathrm{R}_{\mathrm{dyn}}$ has been studied.
Previsione delle prestazioni del veicolo su strada: stato dell’arte
2016
Questo lavoro contiene una rassegna dei metodi che sono usati per la previsione delle prestazioni del veicolo su strada, in dipendenza del motore installato. La prima parte mostra il calcolo delle resistenze al moto, cioè le forze che il veicolo deve vincere per avanzare sulle strade piane e in salita. Particolarmente interessante appare la parte che riguarda la resistenza aerodinamica, della quale si tratta di metodi sperimentali (galleria del vento), metodi empirici e metodi CFD. Si propone inoltre l’applicazione della norma CUNA sulla velocità per la determinazione dei consumi anche al calcolo dei coefficienti aerodinamici. La rassegna esclude la resistenza accidentale in curva perché no…
Multi-pulse characterization of trapping/detrapping mechanisms in AlGaN/GaN high electromobility transistors
2019
GaN high-electro mobility transistors (HEMTs) are among the most promising candidates for use in high-power, high-frequency, and high-temperature electronics owing to their high electrical breakdown threshold and their high saturation electron velocity. The applications of these AlGaN/GaN HEMTs in power converters are limited by the surface trapping effects of drain-current collapse. Charge-trapping mechanisms affect the dynamic performance of all GaN HEMTs used in power switching applications. This study analyzes the dynamic resistance of GaN HEMTs and finds that the effects of dynamic resistance can be suppressed by controlling switching conditions and on-off cycles.
High dynamic resistance elements based on a Josephson junction array
2020
A chain of superconductor–insulator–superconductor junctions based on Al–AlOx–Al nanostructures and fabricated using conventional lift-off lithography techniques was measured at ultra-low temperatures. At zero magnetic field, the low current bias dynamic resistance can reach values of ≈1011 Ω. It was demonstrated that the system can provide a decent quality current biasing circuit, enabling the observation of Coulomb blockade and Bloch oscillations in ultra-narrow Ti nanowires associated with the quantum phase-slip effect.
Assessment of seismic resistance of masonry structures including boundary conditions
2002
The paper is devoted to the investigation of seismic response of the masonry structure and describes experiences with modelling of boundary conditions during the test of large heavy model on 6DOF shaking table. The main aim of the research was how to increase dynamic resistance capacity of old masonry buildings including the medium and strong seismic effects. The results of theoretical and numerical analyses are compared including initial forecasting calculations made before any test started. The emphasis is given to the boundary conditions reached during the excitation of the large masonry model via shaking table. Strengthening and retrofitting procedures and their effects are discussed wh…
Optimization of a Vehicle Shape by CFD Code
2005
In this paper, fluid dynamics simulations have been executed using a CFD (Computational Fluid Dynamics) commercial code, on a Maserati Biturbo mod. 222 - 1988. At first some surfaces are optimised, choosing the more important ones for the reduction of the resistance, by a manual variation of their geometry, hence a large surface is optimised in an automatic way, by means of an own software, developed in the MatLab environment, returning the optimised surface according to a specific objective function (the resistance in this paper). The aerodynamics resistance results are given under the form of aerodynamics penetration coefficient CD, taking into account the vehicle shape effect, the speed,…