2.4 GHz high-efficiency power-combining Class-E amplifier with transmission-line harmonic traps

Experimental assessments of the modified power-combining Class-E amplifier are described. The technique used to combine the output of individual power amplifiers (PAs) into an unbalanced load without the need for bulky transformers permits the use of small RF chokes useful for the deployment in the EER transmitter. The modified output load network of the PA results in excellent 50 dBc and 46 dBc second and third-harmonic suppressions, dispensing the need for additional lossy filtering block. Operating from a 3.2 V dc supply voltage, the PA exhibits 64% drain efficiency at 24 dBm output power. Over a wide bandwidth of 350 MHz, drain efficiency of better than 60% at output power higher than 22 dBm were achieved. © 2010 IEICE Institute of Electronics Informati.

Design technique for mm-wave IC realization of the load network of switched-mode class-EF power amplifier

Analysis and synthesis of the new Class-EF power amplifier (PA) are presented in this paper. The proposed circuit offers means to alleviate some of the major issues faced by existing Class-EF and Class-EF PAs, such as (1) substantial power losses due to parasitic resistance of the large inductor in the Class-EF load network, (2) unpredictable behaviour of practical lumped inductors and capacitors at harmonic frequencies, and (3) deviation from ideal Class-EF operation mode due to detrimental effects of device output inductance at high frequencies. The transmission-line load network of the Class-EF PA topology elaborated in this paper simultaneously satisfies the Class-EF optimum impedance requirements at fundamental frequency, second, and third harmonics as well as simultaneously providing matching to the circuit optimum load resistance for any prescribed system load resistance. Furthermore, an elegant solution using an open and short-circuit stub arrangement is suggested to overcome the problem encountered in the mm-wave IC realizations of the Class-EF PA load network due to lossy quarter-wave line. © 2010 IEICE Institute of Electronics Informati.

Multinational enterprises in Australia: Two decades of international human resource management research reviewed

This paper reviews empirical international human resource management (IHRM) journal articles on foreign- and indigenous-owned multinational enterprises (MNEs) operating in Australia. More specifically, we explore the extent to which papers using Australian data in this area are being published in 53 of the world's leading academic journals and identify the topics that have been researched. We then propose a number of research areas, of Australian and international interest, that researchers could pursue in the future. Our findings point to a picture of limited publications in the leading international journals. There is also support for recent arguments that substantial capacity exists for a greater theoretical contribution by researchers in the IHRM field.

Exploring the impact of institutional and organizational factors on the reaction of MNCs to the global financial crisis

This paper analyses some of the factors that impact multinational companies' (MNCs) reaction to the global financial crisis. This paper reports the results from a large-scale study of its impact on MNCs in Australia, considering occurrences of site closures, offshoring, outsourcing, labour force reductions, reductions in working hours, salary reductions, and reductions in training and travel. Evidence showed that MNC reactions varied according to certain institutional and organizational effects. For example, MNCs originating from liberal-market economies are more likely to have offshored and outsourced production and reduced employment. The implications for understanding of MNC behaviour are discussed. © 2013 Copyright Taylor and Francis Group, LLC.

Identification of the Dynamic Parameters of a Real Bridge under Different Damage Conditions in a Field Experiment

This paper presents the results of a real bridge field experiment in which damage was applied artificially to a steel truss bridge. The aim of this paper is to identify the dynamic parameters of this bridge using conventional techniques and investigate the effect of various damage conditions on those parameters. In the field experiment, acceleration measurements were recorded at a number of locations on the bridge deck. To excite the bridge, a two-axle van was driven across the bridge at constant speed. Dynamic parameters, such as the bridge mode shape, natural frequency and damping constant, are identified from the acceleration signals using existing techniques such as the fast Fourier transform, logarithmic decrement and frequency domain decomposition. The variation of these parameters under the influence of artificially applied damage conditions is investigated in order to evaluate their sensitivity to the bridge damage.

Phosphorus Adsorption onto an Industrial Acidified Laterite By‒Product: Equilibrium and Thermodynamic Investigation

The present research investigates the uptake of phosphate ions from aqueous solutions using acidified laterite (ALS), a by-product from the production of ferric aluminium sulfate using laterite. Phosphate adsorption experiments were performed in batch systems to determine the amount of phosphate adsorbed as a function of solution pH, adsorbent dosage and thermodynamic parameters per fixed P concentration. Kinetic studies were also carried out to study the effect of adsorbent particle sizes. The maximum removal capacity of ALS observed at pH 5 was 3.68 mg P g^-1. It was found that as the adsorbent dosage increases, the equilibrium pH decreases, so an adsorbent dosage of 1.0 g L^-1 of ALS was selected. Adsorption capacity (q_m) calculated from the Langmuir isotherm was found to be 2.73 mg g^-1. Kinetic experimental data were mathematically well described using the pseudo first-order model over the full range of the adsorbent particle size. The adsorption reactions were endothermic, and the process of adsorption was favoured at high temperature; the ΔG and ΔH values implied that the main adsorption mechanism of P onto ALS is physisorption. The desorption studies indicated the need to consider a NaOH 0.1M solution as an optimal solution for practical regeneration applications.

Beneficiary accountability in NGOs: can it be better in donor funded projects as compared to non-donor funded projects?

Prior research on NGO accountability argued that in the process of upward accountability to donors NGOs’ accountability towards beneficiaries had been compromised. With a focus on beneficiary accountability this paper undertakes a comparative examination of a donor funded project and a non-donor funded project. The study has been carried out in the context of a large Bangladeshi NGO with international operations. While the above conclusion on NGO accountability generally holds our study shows a somewhat different picture. Drawing on a comprehensive set of empirical evidence from various sources such as documentary analysis, interviews, focus groups and observations we show that beneficiary accountability can be better in donor funded projects as compared to non-donor funded projects. We theorise the circumstances under which it can happen. This finding has significant implications for the policy makers and donors in the context of recent drive for the self-sustainability of NGOs and its impact on the crucial issue of beneficiary accountability.