Beamforming in Two-Way Fixed Gain Amplify-and-Forward Relay Systems with CCI

We analyze the outage performance of a two-way fixed gain amplify-and-forward (AF) relay system with beamforming, arbitrary antenna correlation, and co-channel interference (CCI). Assuming CCI at the relay, we derive the exact individual user outage probability in closed-form. Additionally, while neglecting CCI, we also investigate the system outage probability of the considered network, which is declared if any of the two users is in transmission outage. Our results indicate that in this system, the position of the relay plays an important role in determining the user as well as the system outage probability via such parameters as signal-to-noise imbalance, antenna configuration, spatial correlation, and CCI power. To render further insights into the effect of antenna correlation and CCI on the diversity and array gains, an asymptotic expression which tightly converges to exact results is also derived.Comment: Accepted for presentation on IEEE International Conference on Communications (ICC 2012), Ottawa, Canada, June 201

Ethnic Fragmentation, Conflict, Displaced Persons and Human Trafficking: An Empirical Analysis

Ethnic conflicts and their links to international human trafficking have recently received a surge in international attention. It appears that ethnic conflicts exacerbate the internal displacement of individuals from networks of family and community, and their access to economic and social safety nets. These same individuals are then vulnerable to being trafficked by the hopes of better economic prospects elsewhere. In this paper, we empirically examine this link between ethnic fragmentation, conflicts, internally displaced persons (IDPs), refugees and international trafficking, making use of a novel dataset of international trafficking. We conduct a direct estimation, which highlights the ultimate impact of ethnic fragmentation and conflict on international trafficking through internal and international displacements.ethnic fragmentation, conflict, displaced persons, human trafficking

Transnational Trafficking, Law Enforcement and Victim Protection: A Middleman Trafficker's Perspective

We explore three hitherto poorly understood characteristics of the human trafficking market – the cross-border ease of mobility of traffickers, the relative bargaining strength of traffickers and final buyers, and the elasticity of buyers' demand. In a model of two-way bargaining, the exact configuration of these characteristics is shown to determine whether domestic and foreign crackdowns on illicit employment mutually reinforce or counteract one another in efforts to stem the tide of trafficking. Estimation results from a gravity model of trafficking present evidence consistent with the mutual reinforcement view, indicating considerable ease of mobility, partial bargaining power, and inelastic demand.human trafficking, two-way Nash bargaining, victim protection, law enforcement

Control and operation of a new 8/6-pole doubly salient permanent-magnet motor drive

This paper proposes a new 8/6-pole doubly salient permanent-magnet (DSPM) motor drive, which offers the advantages of higher power density, higher efficiency, and wider speed range. The corresponding control and operation of the motor drive are presented. A variable proportional-integral (PI) controller combined with bang-bang control for the DSPM motor drive is developed. Two operation modes, namely, four-phase and two-phase operation modes, are proposed for the 8/6-pole DSPM motor drive. The drive system is implemented and tested. The results show that the developed control scheme can operate the DSPM motor properly, and the DSPM motor drive offers high efficiency over wide power range and good dynamic performance. Furthermore, the two-phase operation mode of the 8/6-pole DSPM motor offers the possibility of eliminating the torque ripple of the motor drive.published_or_final_versio

Subharmonics and chaos in switched reluctance motor drives

In this paper, the investigation of the nonlinear dynamics of an adjustable speed switched reluctance motor (SRM) drive with voltage PWM regulation is carried out. The corresponding bifurcation diagrams and chaotic Poincare sections are presented. It shows that the system generally exhibits a period-doubling route to chaos.published_or_final_versio

Subharmonics and chaos in switched reluctance motor drives

In this paper, the investigation of the nonlinear dynamics of an adjustable-speed switched reluctance motor (SRM) drive with voltage pulse width modulation (PWM) regulation is carried out. Nonlinear iterative mappings based on both nonlinear and approximately linear flux linkage models are derived, hence the corresponding subharmonic and chaotic behaviors are analyzed. Although both flux linkage models can produce similar results, the nonlinear one offers the merit of accuracy but with the sacrifice of computational time. Moreover, the bifurcation diagrams show that the system generally exhibits a period-doubling route to chaos.published_or_final_versio

Torque ripple minimization of doubly salient permanent-magnet motors

Due to the nature of salient poles in both the stator and rotor, the doubly salient permanent-magnet (DSPM) motor suffers from severe torque ripples. In this paper, the torque ripple of DSPM motors is analyzed, and the torque ripple factor is newly derived. A new approach, namely the conduction angle control, is proposed to minimize the torque ripple. Moreover, the genetic algorithm is employed to optimize the corresponding control angles. Computer simulation and experimental results are given to verify the proposed approach. © 2005 IEEE.published_or_final_versio

Modeling and analysis of chaotic behavior in switched reluctance motor drives

In this paper, modeling and analysis of chaotic behavior in switched reluctance (SR) motor drives using voltage PWM regulation is presented. The key is to derive a Poincare map that is based on the nonlinear flux linkage model. Its Jacobian matrix can be evaluated by solving the corresponding variational equation. Based on the Poincare map and its Jacobian matrix, the analysis of chaotic behavior is presented. Furthermore, bifurcation diagrams are also figured out. They facilitate to determine the stable range of various system parameters so as to avoid the occurrence of chaos. Both computer simulations and experimental measurements are given to verify the theoretical modeling and analysis.published_or_final_versio

Sulodexide decreases albuminuria and regulates matrix protein accumulation in C57BL/6 mice with streptozotocin-induced type I diabetic nephropathy

OBJECTIVE: Sulodexide is a mixture of glycosaminoglycans that may reduce proteinuria in diabetic nephropathy (DN), but its mechanism of action and effect on renal histology is not known. We investigated the effect of sulodexide on disease manifestations in a murine model of type I DN. METHODS: Male C57BL/6 mice were rendered diabetic with streptozotocin. After the onset of proteinuria, mice were randomized to receive sulodexide (1 mg/kg/day) or saline for up to 12 weeks and renal function, histology and fibrosis were examined. The effect of sulodexide on fibrogenesis in murine mesangial cells (MMC) was also investigated. RESULTS: Mice with DN showed progressive albuminuria and renal deterioration over time, accompanied by mesangial expansion, PKC and ERK activation, increased renal expression of TGF-β1, fibronectin and collagen type I, III and IV, but decreased glomerular perlecan expression. Sulodexide treatment significantly reduced albuminuria, improved renal function, increased glomerular perlecan expression and reduced collagen type I and IV expression and ERK activation. Intra-glomerular PKC-α activation was not affected by sulodexide treatment whereas glomerular expression of fibronectin and collagen type III was increased. MMC stimulated with 30 mM D-glucose showed increased PKC and ERK mediated fibronectin and collagen type III synthesis. Sulodexide alone significantly increased fibronectin and collagen type III synthesis in a dose-dependent manner in MMC and this increase was further enhanced in the presence of 30 mM D-glucose. Sulodexide showed a dose-dependent inhibition of 30 mM D-glucose-induced PKC-βII and ERK phosphorylation, but had no effect on PKC-α or PKC-βI phosphorylation. CONCLUSIONS: Our data demonstrated that while sulodexide treatment reduced proteinuria and improved renal function, it had differential effects on signaling pathways and matrix protein synthesis in the kidney of C57BL/6 mice with DN.published_or_final_versio

Causal Strategic Learning with Competitive Selection

We study the problem of agent selection in causal strategic learning under multiple decision makers and address two key challenges that come with it. Firstly, while much of prior work focuses on studying a fixed pool of agents that remains static regardless of their evaluations, we consider the impact of selection procedure by which agents are not only evaluated, but also selected. When each decision maker unilaterally selects agents by maximising their own utility, we show that the optimal selection rule is a trade-off between selecting the best agents and providing incentives to maximise the agents' improvement. Furthermore, this optimal selection rule relies on incorrect predictions of agents' outcomes. Hence, we study the conditions under which a decision maker's optimal selection rule will not lead to deterioration of agents' outcome nor cause unjust reduction in agents' selection chance. To that end, we provide an analytical form of the optimal selection rule and a mechanism to retrieve the causal parameters from observational data, under certain assumptions on agents' behaviour. Secondly, when there are multiple decision makers, the interference between selection rules introduces another source of biases in estimating the underlying causal parameters. To address this problem, we provide a cooperative protocol which all decision makers must collectively adopt to recover the true causal parameters. Lastly, we complement our theoretical results with simulation studies. Our results highlight not only the importance of causal modeling as a strategy to mitigate the effect of gaming, as suggested by previous work, but also the need of a benevolent regulator to enable it.Comment: Corrected some in-text citation