39 research outputs found
Granular flow down a rough inclined plane: transition between thin and thick piles
The rheology of granular particles in an inclined plane geometry is studied
using molecular dynamics simulations. The flow--no-flow boundary is determined
for piles of varying heights over a range of inclination angles . Three
angles determine the phase diagram: , the angle of repose, is the
angle at which a flowing system comes to rest; , the maximum angle
of stability, is the inclination required to induce flow in a static system;
and is the maximum angle for which stable, steady state flow is
observed. In the stable flow region , three
flow regimes can be distinguished that depend on how close is to
: i) : Bagnold rheology, characterized by a
mean particle velocity in the direction of flow that scales as
, for a pile of height , ii)
: the slow flow regime, characterized by a linear
velocity profile with depth, and iii) : avalanche flow
characterized by a slow underlying creep motion combined with occasional free
surface events and large energy fluctuations. We also probe the physics of the
initiation and cessation of flow. The results are compared to several recent
experimental studies on chute flows and suggest that differences between
measured velocity profiles in these experiments may simply be a consequence of
how far the system is from jamming.Comment: 19 pages, 14 figs, submitted to Physics of Fluid
Modeling and Design of L-Complementary Self-Oscillating Class D Inverter with Output Voltage Clamping
New mathematical models of L-Complementary self-oscillating class D inverter with output voltage clamping in the steady state and during starting are proposed in this paper. The proposed models are very useful for predicting the converter operation and optimizing the circuit design. Experimental results for 42watt spiral CFL electronic ballast are presented to validate the analysis
New Model of L-Complementary Self-Oscillating Class D Inverter with Output Voltage Clamping
In this paper, a detailed time domain analysis and accurate time domain model of L-Complementaryself-oscillating class D inverter with output voltage clamping in the steady state is proposed. The proposed model is very useful for predicting the converter voltages and currents as well as for optimizing the circuit design. Experimental results for 42watt spiral CFL electronic ballast are presented to validate the analysis
New Model of L-Complementary Self-Oscillating Class D Inverter with Output Voltage Clamping
In this paper, a detailed time domain analysis and accurate time domain model of L-Complementaryself-oscillating class D inverter with output voltage clamping in the steady state is proposed. The proposed model is very useful for predicting the converter voltages and currents as well as for optimizing the circuit design. Experimental results for 42watt spiral CFL electronic ballast are presented to validate the analysis
Modeling and Design of L-Complementary Self-Oscillating Class D Inverter with Output Voltage Clamping
New mathematical models of L-Complementary self-oscillating class D inverter with output voltage clamping in the steady state and during starting are proposed in this paper. The proposed models are very useful for predicting the converter operation and optimizing the circuit design. Experimental results for 42watt spiral CFL electronic ballast are presented to validate the analysis
Active Remembering, Selective Forgetting, and Collective Identity: The Case of Bloody Sunday
Bloody Sunday. Derry, Northern Ireland, January 30, 1972, in which 13 Catholic civilians were shot dead by the British army has evoked two contesting memories - an 'official' or elite memory and a folk memory among the Nationalist community that, it is argued, has been omitted from dominant memory discourses. The official memory of this life- destroying historical event is encoded in the report of the Widgery Tribunal established by the British government in the aftermath of bloody Sunday. A second popular memory has emerged in resistance to this that carries the remembrances of the victims'families and of the wider Nationalist community in Northern Ireland. I explore the mediums through which this unofficial memory has been established and maintained, the meanings associated with it, and how and why these have changed over time. Traditionally, it has been invested with a negative meaning associated with sectarianism, colonialism, and victimization. In recent times, the folk memory has been framed within a broader global context with a focus on its healing and reconciliation potential, which, together with institutional statements such as the Dowling Street Declaration and the Good Friday Agreement, points to the emergence of a more inclusivist understanding of collective identity-formation in Northern Ireland