896 resultados para pulse-shaping
Resumo:
In our complex and incongruous professional worlds, where there is no blueprint for dealing with unpredictable people and events, it is imperative that individuals develop reflexive approaches to professional identity building. Notwithstanding the importance of disciplinary knowledge and skills, higher education has a crucial role to play in guiding students to examine and mediate self in relation to context for effective decision-making and action. This paper reports on a small-scale longitudinal project that investigated the ways in which ten undergraduate students over the course of a three-year Radiation Therapy degree shaped their professional identities. Theories of reflexivity and methods of discourse analysis are utilised to understand the ways in which individuals accounted for their professional identity projects at university. The findings suggest that, across time, the participants negotiated professional ‘becoming’ through four distinct kinds of reflexive modalities. These findings have implications for teaching strategies and curriculum design in undergraduate programs.
Resumo:
The hardware and the software details of a user-friendly, simple, flexible and inexpensive pulse programmer using programmable counters interfaced to a microprocessor are described. The control of the various parameters that are required for NMR applications is implemented using the microprocessor. The basic hardware is extendable to other applications which require programmable pulse trains.
Resumo:
This paper presents research which examined perceptions on the future of work in Queensland. It highlights the major drivers of change including: changing technology, demographics, increasing globalisation and economic shifts. Focus groups were conducted and findings show that Queensland businesses are acutely aware of the coming changes, but are less certain about how to respond. Current good practices plus recommendations for the future - particularly the lead role government and industry bodies need to play - are discussed. These recommendations will support Queensland businesses to thrive and adapt to the forces shaping work in this changing regional economy.
Resumo:
Management of Tobacco streak virus in sunflower and pulse crops.
Resumo:
Diseases remain a significant impediment to the achievement of maximum yield potential of pulses (chickpea, peanut and mungbean) and sunflowers in the GRDC northern region. This project worked closely with public and private breeding programs to identify sources of resistance to the major diseases of pulses and sunflower that dominate in the region. Through varied surveillance activities, a watching brief on pulse and sunflower diseases was maintained and a timely and appropriate response was made to several significant disease outbreaks. Information on the biology and management of diseases was extended to clients in a wide variety of ways.
Resumo:
Epidemiology and management of tobacco streak virus in sunflower and pulse crops.
Resumo:
The theory of transient mode locking for an active modulator in an intracavity frequency-doubled laser is presented. The theory is applied to mode-locked and intracavity frequency-doubled Nd:YAG laser and the mode-locked pulse width is plotted as a function of number of round trips inside the cavity. It is found that the pulse compression is faster and the system takes a very short time to approach the steady state in the presence of a second harmonic generating crystal inside the laser cavity. The effect of modulation depth and the second harmonic conversion efficiency on the temporal behavior of the pulse width is discussed.
Resumo:
The stability of the steady-state solutions of mode-locking of cw lasers by a fast saturable absorber is imvestigated. It is shown that the solutions are stable if the condition (Ps/Pa) = (2/3) (P0Pa) is satisfied, where (Ps/Pa) is the steady-state la ser power, (P0/Pa) is the power at mode-locking threshold, and Pa is the saturated power of the absorber.
Resumo:
Need to analyze particles in a flow? This system takes electrical pulses from acoustical or optical sensors and groups them into bands representing ranges of particle sizes.
Resumo:
Recent international trends towards urban consolidation, intended to reduce outward urban sprawl by concentrating growth within existing neighbourhoods, can cause contention in cities. Understanding how the mass media represents urban consolidation can lead to more informed and democratic planning practices. This paper employs Social Representations Theory to identify and understand representations of urban consolidation in newspaper media. The theory recognises that the media is a key purveyor of public discourse and can reflect, shape or suppress ideas circulating in society. This novel approach has not previously been applied to understanding social representations of urban consolidation strategies in the mass media. The rapidly growing and changing city of Brisbane, Australia, is utilised as a case study. Brisbane is situated in South East Queensland, the fastest growing region in Australia, and is governed by regional and local planning policies that strongly support increased densities in existing urban areas. Findings from a quantitative textual analysis of 449 articles published in Brisbane newspapers between 2007 and 2014 reveal key clusters and classes of co-occurring words that represent dominant social representations apparent in the newspaper corpus. The paper provides two key conclusions. The first is that social representations occurring in mass media represent an important source of information about ‘common sense’ understandings and evaluations of urban consolidation debates. The second is that urban consolidation is represented as a ultifaceted issue, including interrelated themes of housing,sustainable population growth, investment strategies and the interplay between politics and planning
Resumo:
NMR spectroscopy enables the study of biomolecules from peptides and carbohydrates to proteins at atomic resolution. The technique uniquely allows for structure determination of molecules in solution-state. It also gives insights into dynamics and intermolecular interactions important for determining biological function. Detailed molecular information is entangled in the nuclear spin states. The information can be extracted by pulse sequences designed to measure the desired molecular parameters. Advancement of pulse sequence methodology therefore plays a key role in the development of biomolecular NMR spectroscopy. A range of novel pulse sequences for solution-state NMR spectroscopy are presented in this thesis. The pulse sequences are described in relation to the molecular information they provide. The pulse sequence experiments represent several advances in NMR spectroscopy with particular emphasis on applications for proteins. Some of the novel methods are focusing on methyl-containing amino acids which are pivotal for structure determination. Methyl-specific assignment schemes are introduced for increasing the size range of 13C,15N labeled proteins amenable to structure determination without resolving to more elaborate labeling schemes. Furthermore, cost-effective means are presented for monitoring amide and methyl correlations simultaneously. Residual dipolar couplings can be applied for structure refinement as well as for studying dynamics. Accurate methods for measuring residual dipolar couplings in small proteins are devised along with special techniques applicable when proteins require high pH or high temperature solvent conditions. Finally, a new technique is demonstrated to diminish strong-coupling induced artifacts in HMBC, a routine experiment for establishing long-range correlations in unlabeled molecules. The presented experiments facilitate structural studies of biomolecules by NMR spectroscopy.
Resumo:
An alternative approach to digital PWM generation uses an accumulator rather than a counter to generate the carrier. This offers several advantages. The resolution and gain of the pulse width modulator remain constant regardless of the module clock frequency and PWM output frequency. The PWM resolution also becomes fixed at the register width. Even at high PWM frequencies, the resolution remains high when averaged over a number of PWM cycles. An inherent dithering of the PWM waveform introduced over successive cycles blurs the switching spectra without distorting the modulating waveform. The technique also lends itself to easily generating several phase shifted PWM waveforms suitable for multilevel converter modulation. Several example waveforms generated using both simulation and FPGA hardware are presented.
Resumo:
This paper presents a systematic method of investigating the existence of limit cycle oscillations in feedback systems with combined integral pulse frequency-pulse width (IPF-P/V) modulation. The method is based on the non-linear discrete equivalence of the continuous feedback system containing the IPF-PW modulator.
Resumo:
The discharge pulse rates at different magnitude levels are often used as criteria for monitoring the partial-discharge aging of insulation systems. Use of suggested corrections for errors in cumulative probability counting leads to better use of available counters.
Resumo:
A versatile and flexible digital pulse programmer for two-pulse, three-pulse, saturation burst and Carr-Purcell sequences is described. Independently variable controls for pulse widths (0.2 mu s to 100 mu s), delay between pulses (0.2 mu s to 100 s) and for number of pulses (1 to 99) for the saturation burst and for the Carr-Purcell sequence, are brought to the front panel. The programmer can be used for one-shot experiments as well as for repetitive experiments.