Detection and Combining Techniques for Asynchronous Random Access with Time Diversity

Asynchronous random access (RA) protocols are particularly attractive for their simplicity and avoidance of tight synchronization requirements. Recent enhancements have shown that the use of successive interference cancellation (SIC) can largely boost the performance of these schemes. A further step forward in the performance can be attained when diversity combining techniques are applied. In order to enable combining, the detection and association of the packets to their transmitters has to be done prior to decoding. We present a solution to this problem, that articulates into two phases. Non-coherent soft-correlation as well as interference-aware soft-correlation are used for packet detection. We evaluate the detection capabilities of both solutions via numerical simulations. We also evaluate numerically the spectral efficiency achieved by the proposed approach, highlighting its benefits.Comment: 6 pages, 7 figures. Work has been submitted to the 11th International ITG Conference on Systems, Communications and Coding 201

Assessment of a Universal Reconfiguration-less Control Approach in Open-Phase Fault Operation for Multiphase Drives

Multiphase drives have been important in particular industry applications where reliability is a desired goal. The main reason for this is their inherent fault tolerance. Di erent nonlinear controllers that do not include modulation stages, like direct torque control (DTC) or model-based predictive control (MPC), have been used in recent times to govern these complex systems, including mandatory control reconfiguration to guarantee the fault tolerance characteristic. A new reconfiguration-less approach based on virtual voltage vectors (VVs) was recently proposed for MPC, providing a natural healthy and faulty closed-loop regulation of a particular asymmetrical six-phase drive. This work validates the interest in the reconfiguration-less approach for direct controllers and multiphase drives

Argentina in a Changing Nuclear Order: An Appraisal

This chapter examines Argentina´s nucleary policy regarding non-proliferation and how it fits into its more general foreign policy. It argues that Argentina?s nuclear preferences have evolved to focus on lines of dialogue,confidence building, and incremental engagement with the global nuclear order.Fil: Merke, Mario Federico. Universidad de San Andrés; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

New Results On Censored Regression with Applications to Transactions Costs, Household Decisions and Food Purchases

We generalize the Tobit censored regression to permit unique unobserved censoring thresholds conditioned by covariates and a set of common response coefficients. This situation , we argue, is one arising frequently in applications of censored regression and we provide three diverse examples to motivate the theory. We derive a robust estimation algorithm with three noteworthy features. First, by augmenting the observed-data likelihood with the censored observations, the estimation strategy is the same as Chib (1992) who derives Bayes estimates of the conventional censored regression. Second, by virtue of its generality, the model is applicable to a much broader set of circumstances than the conventional Tobit regression, which is nested as a special case of the more general framework. Third, despite its generality and wide applicability, the estimation algorithm is very simple, evidencing routine application of Markov chain Monte Carlo methods (MCMC)-Gibbs sampling in particular- and requiring only modest extensions of the basic algorithm in Chib (1992). The model and procedures are illustrated empirically in three applications that we use to motivate the theory, namely problems in transactions-costs economics, household decision-making and food-consumption.conditionally censored Tobit regression, Bayes inference, Food Consumption/Nutrition/Food Safety, O11, C34, O13,

Near-infrared spectroscopy study of tourniquet-induced forearm ischaemia in patients with coronary artery disease

Near-Infrared Spectroscopy (NIRS) can be employed to monitor local changes in haemodynamics and oxygenation of human tissues. A preliminary study has been performed in order to evaluate the NIRS transmittance response to induced forearm ischaemia in patients with coronary artery disease (CAD). The population consists in 40 patients with cardiovascular risk factors and angiographically documented CAD, compared to a group of 13 normal subjects. By inflating and subsequently deflating a cuff placed around the patient arm, an ischaemia has been induced and released, and the patients have been observed until recovery of the basal conditions. A custom NIRS spectrometer (IRIS) has been used to collect the backscattered light intensities from the patient forearm throughout the ischaemic and the recovery phase. The time dependence of the near-infrared transmittance on the control group is consistent with the available literature. On the contrary, the magnitude and dynamics of the NIRS signal on the CAD patients show deviations from the documented normal behavior, which can be tentatively attributed to abnormal vessel stiffness. These preliminary results, while validating the performance of the IRIS spectrometer, are strongly conducive towards the applicability of the NIRS technique to ischaemia analysis and to endothelial dysfunction characterization in CAD patients with cardiovascular risk factors

Lung cancer epidemiology in North Sardinia, Italy

Background The aim of this study was to analyze and describe the epidemiological characteristics and trends of lung cancer in North Sardinia, Italy, in the period 1992–2010. Methods Data were obtained from the tumor registry of Sassari province which is a part of a wider registry web, coordinated today by the Italian Association for Tumor Registries. Results The overall number of lung cancer cases registered was 4,325. The male-to-female ratio was 4.6:1 and the mean age 68.1 years for males and 67 years for females. The standardized incidence rates were 73.1/100,000 and 13.5/100,000 and the standardized mortality rates 55.7/100,000 and 9.9/100,000 for males and females, respectively. An increasing trend in incidence of lung cancer in women was evidenced. Conversely, incidence was found to decrease in males. Relative survival at 5 years from diagnosis was low (8.8% for males and 14.9% for females). Furthermore, an increase in mortality rates was observed in both sexes in the period under investigation. Conclusions Our data show an increasing trend of lung cancer incidence in women in North Sardinia in the last decades. Conversely, a reduction of incidence rates was observed in males. Furthermore, a slightly increasing trend in mortality rates was observed in both sexes, suggesting the need to enhance smoking control strategies, consider adoption of effective surveillance policies, and improve diagnosis and treatment methods

Markets as networks: the embeddedness of private security in Argentina

A partir de un estudio de la seguridad privada en Argentina, exploramos algunas hipótesis desarrolladas en el ámbito de la sociología económica para el estudio de los mercados: por un lado, que los empresarios utilizan sus contactos y su reputación para crear y mantener una clientela; por otro, que las empresas tratan de ocupar nichos para evitar una lucha abierta y frontal con sus competidores. Siguiendo las ideas desarrolladas por Mark Granovetter, Harrison White y Wayne Baker, el artículo muestra que la conformación de un mercado no es la respuesta a una demanda preexistente, sino el resultado de la iniciativa de los empresarios y de las estrategias de adaptación de las empresas, y que los mercados en general no se organizan como realidades simples y homogéneas, sino como estructuras diferenciadas de roles fundadas en redes limitadas y restrictivas.Based on an inquiry into private security in Argentina, this paper explores some hypotheses developed in the field of economic sociology to study markets: on the one hand, that entrepreneurs use their contacts and reputation to create and maintain a clientele; on the other hand, that companies try to fill niches to avoid an open competition with its contenders. Following the ideas developed by Mark Granovetter and Wayne Baker, the paper shows that the development of a market is not the response to an existing demand, but the result of the initiative of entrepreneurs and the strategies of firms, and that markets generally are not organized as simple and homogeneous realities, but as distinct structures of roles based on limited and restrictive networks.Fil: Lorenc Valcarce, Federico Mario. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin