DOA Estimation in Partially Correlated Noise Using Low-Rank/Sparse Matrix Decomposition

We consider the problem of direction-of-arrival (DOA) estimation in unknown partially correlated noise environments where the noise covariance matrix is sparse. A sparse noise covariance matrix is a common model for a sparse array of sensors consisted of several widely separated subarrays. Since interelement spacing among sensors in a subarray is small, the noise in the subarray is in general spatially correlated, while, due to large distances between subarrays, the noise between them is uncorrelated. Consequently, the noise covariance matrix of such an array has a block diagonal structure which is indeed sparse. Moreover, in an ordinary nonsparse array, because of small distance between adjacent sensors, there is noise coupling between neighboring sensors, whereas one can assume that nonadjacent sensors have spatially uncorrelated noise which makes again the array noise covariance matrix sparse. Utilizing some recently available tools in low-rank/sparse matrix decomposition, matrix completion, and sparse representation, we propose a novel method which can resolve possibly correlated or even coherent sources in the aforementioned partly correlated noise. In particular, when the sources are uncorrelated, our approach involves solving a second-order cone programming (SOCP), and if they are correlated or coherent, one needs to solve a computationally harder convex program. We demonstrate the effectiveness of the proposed algorithm by numerical simulations and comparison to the Cramer-Rao bound (CRB).Comment: in IEEE Sensor Array and Multichannel signal processing workshop (SAM), 201

The Role of KM Tactical Factors in Supply Chain Management for Gaining Competitive Advantage

Supply chain management (SCM) has assumed a leading operations strategy position in both manufacturing and service industries, and over the past 10 years companies have seriously implemented supply chain management strategies in their organizations. knowledge management(KM) is a major enabler of supply chain management, and is a critical element in information intensive and multi-cultured enterprise environments. The present study aimed to investigate the role of KM tactical factors in gaining competitive advantage in organizations. For this purpose, four tactical factors of KM (knowledge acquisition, knowledge sharing, learning from KM process, and knowledge application) and five indicators of gaining competitive advantage (timely supply of products) were studied and the relationships between them were analyzed.The statistical findings confirmed the effect of KMtactical factors on gaining competitive advantage. In addition, the results indicated that KM process should be scientifically implemented by using experts to gain competitive advantage. Creating the necessary infrastructures and appropriate acculturalization seem essential

Successive Concave Sparsity Approximation for Compressed Sensing

In this paper, based on a successively accuracy-increasing approximation of the $\ell_0$ norm, we propose a new algorithm for recovery of sparse vectors from underdetermined measurements. The approximations are realized with a certain class of concave functions that aggressively induce sparsity and their closeness to the $\ell_0$ norm can be controlled. We prove that the series of the approximations asymptotically coincides with the $\ell_1$ and $\ell_0$ norms when the approximation accuracy changes from the worst fitting to the best fitting. When measurements are noise-free, an optimization scheme is proposed which leads to a number of weighted $\ell_1$ minimization programs, whereas, in the presence of noise, we propose two iterative thresholding methods that are computationally appealing. A convergence guarantee for the iterative thresholding method is provided, and, for a particular function in the class of the approximating functions, we derive the closed-form thresholding operator. We further present some theoretical analyses via the restricted isometry, null space, and spherical section properties. Our extensive numerical simulations indicate that the proposed algorithm closely follows the performance of the oracle estimator for a range of sparsity levels wider than those of the state-of-the-art algorithms.Comment: Submitted to IEEE Trans. on Signal Processin

L’influence du système scolaire français sur le système scolaire iranien de l’inauguration de l’école Dar ol-Fonoun jusqu’à la fin de l’époque des Qâdjârs (1851-1925)

La présente thèse de recherche concerne l’évolution du système éducatif iranien à l’époque des Qâdjârs, et étudie notamment le rôle qu’y ont eu la France et les acteurs français. Il s’agit de mettre en, exergue l’influence du système éducatif français sur celui de l’Iran, sans pour autant être une comparaison de ces deux systèmes. Ce travail est une recherche historique, qui prend pour but d’étudier le processus de formation d’une structure scolaire moderne en Iran de 1851 à 1925. En prenant contact avec l’Occident, l’Iran du début du XIXème siècle cherche à combler son retard par rapport aux pays européens industrialisés, en leur empruntant savoirs, technologies et méthodes. La mise en place d’un système éducatif radicalement différent de la structure préexistante des écoles coraniques, dites maktab, participe de ce mouvement et est vue par les élites progressistes comme une condition sine qua non à la modernisation du pays. Le modèle éducatif français leur apparait comme étant le meilleur à suivre, et avec lui se diffusent dans le pays la langue et la culture française. Dans cette thèse de doctorat, nous entendons d’abord analyser l’arrière-plan sociopolitique à la mise en place d’un nouveau système scolaire, via la fondation d’écoles modernes, en Iran. Nous tâchons ensuite d’étudier les modalités de mise en œuvre de ce système par les acteurs aussi bien étatiques que privés, tant français qu’iraniens.The present work concerns the evolution of the educational system in Iran during the Qâdjâr dynasty and the role the French state and French actors played in this evolution. It seeks to highlight the influence of the French educational system on that of Iran, while at the same time avoiding a comparison between the two systems. This is a work of historical research, that aims to study the process of the creation of a modern educational system in Iran between 1851 and 1925. In seeking out the West, early 19th century Iran looked to make up for its tardiness in relation to industrialised European nations by borrowing their knowledge, technology and methods. Putting in place an educational system radically different from the preexisting system based on Quranic schools, called maktab, was a part of this movement and was seen by the progressive elite as a necessary condition for the modernisation of the country. The French educational model seemed to them to be the best one to follow, and with it French language and culture spread throughout the country. In this doctoral thesis, I intend first to analyse the socio-political backdrop of the installation of this new educational system via the creation of modern schools in Iran. I will then look at the modalities of the implementation of the system by both state and private actors, both Iranian and French

Moḥammad Afshīn Vafā’ī, Peymān Fīrūz Bakhsh (eds.). Yād dāsht hāy-e Rūzāneh Moḥammad ‘Alī Forūghī [Les notes quotidiennes de Moḥammad Alī Forūghī]

Éditées par Moḥammad Afshīn Vafā’ī et Peymān Fīrūz Bakhsh, les Yād dāsht hāy-e Rūzāneh Mohammad Alī Forūghī contiennent les notes écrites chaque jour par le représentant diplomatique iranien Forūghī, du début de son voyage en Europe, le 17 décembre 1918, jusqu’à son terme, le 11 août 1920. Forūghī fut envoyé avec une délégation diplomatique à Paris afin de négocier la participation de l’Iran à la conférence de la Paix de 1919 à Paris. Cet ouvrage, sorte de mémoire ou de journal, contient des ..

Performance and Robustness Analysis of Co-Prime and Nested Sampling

Coprime and nested sampling are well known deterministic sampling techniques that operate at rates significantly lower than the Nyquist rate, and yet allow perfect reconstruction of the spectra of wide sense stationary signals. However, theoretical guarantees for these samplers assume ideal conditions such as synchronous sampling, and ability to perfectly compute statistical expectations. This thesis studies the performance of coprime and nested samplers in spatial and temporal domains, when these assumptions are violated. In spatial domain, the robustness of these samplers is studied by considering arrays with perturbed sensor locations (with unknown perturbations). Simplified expressions for the Fisher Information matrix for perturbed coprime and nested arrays are derived, which explicitly highlight the role of co-array. It is shown that even in presence of perturbations, it is possible to resolve $O(M^2)$ under appropriate conditions on the size of the grid. The assumption of small perturbations leads to a novel ``bi-affine" model in terms of source powers and perturbations. The redundancies in the co-array are then exploited to eliminate the nuisance perturbation variable, and reduce the bi-affine problem to a linear underdetermined (sparse) problem in source powers. This thesis also studies the robustness of coprime sampling to finite number of samples and sampling jitter, by analyzing their effects on the quality of the estimated autocorrelation sequence. A variety of bounds on the error introduced by such non ideal sampling schemes are computed by considering a statistical model for the perturbation. They indicate that coprime sampling leads to stable estimation of the autocorrelation sequence, in presence of small perturbations. Under appropriate assumptions on the distribution of WSS signals, sharp bounds on the estimation error are established which indicate that the error decays exponentially with the number of samples. The theoretical claims are supported by extensive numerical experiments

Élections à distance et politique diasporique

La suspension des relations diplomatiques entre le Canada et l’Iran en 2012 a eu de graves conséquences sur la capacité d’action politique de la diaspora iranienne résidant au Canada. Empêchés de prendre part à l’élection présidentielle de 2013 en Iran, marquée par la victoire d’Hassan Rohani, les Iraniens du Canada se sont mobilisés pour faire entendre leurs voix. Dans la communauté iranienne de Toronto, par exemple, sont apparus de profonds clivages idéologiques entre les défenseurs du droit de vote à distance et les opposants plus radicaux au régime en place

Uso de criterios múltiples para introducir y clasificar los criterios de diseño de recompensa en proyectos de construcción

The objective of this study was to The Use of Multi-Criteria Decision Making to Introduce and Rank of Design Criteria of Reward in Construction Projects. In this research, the design criteria of rewards in construction projects are ranked. In the present study, in order to identify and rank the criteria of employee reward allocation the methods of Demetel and expansion of the performance of fuzzy quality in two steps were used. the results showed that the professional ethics is the most important criterion for reward allocation to the employees in the construction projects. Results show that considering the work environment of construction projects, maintaining discipline and having organizational commitment and helping others is very important. Also, having the spirit of teamwork and cooperation with others is very important for working in such environments. One of the notable points in the findings of this study is the less attention paid by construction managers to the use of labor quantity measurement indicators as a criterion for reward allocation and more attention to quality criteria such as professional ethics, creativity, etc., which shows the difference between the nature of the work and the end product of this industry with manufacturing industries such as parts manufacturing.El objetivo de este estudio fue el uso de la toma de decisiones de criterios múltiples para introducir y clasificar los criterios de diseño de recompensa en proyectos de construcción. En esta investigación se clasifican los criterios de diseño de recompensas en proyectos de construcción. En el presente estudio, para identificar y clasificar los criterios de asignación de recompensas a los empleados se utilizaron los métodos de Demetel y la expansión del desempeño de calidad difusa en dos pasos. Los resultados mostraron que la ética profesional es el criterio más importante para la asignación de recompensas a los empleados en los proyectos de construcción. Los resultados muestran que considerar el clima laboral de los proyectos de construcción, mantener la disciplina y tener compromiso organizacional y ayudar a los demás es muy importante. Además, tener el espíritu de trabajo en equipo y cooperación con los demás es muy importante para trabajar en estos entornos. Uno de los puntos destacables en los hallazgos de este estudio es la menor atención prestada por los gerentes de obra al uso de indicadores de medición de cantidad de mano de obra como criterio para la asignación de recompensas y mayor atención a criterios de calidad como la ética profesional, la creatividad, etc., que muestra la diferencia entre la naturaleza del trabajo y el producto final de esta industria con industrias manufactureras como la fabricación de piezas

Impact of Government Size on Employment in Iran

Given that the role of government is crucial in Iran’s economy, therefore, clarifying the role of government size employment can be very important; especially from the aspect that public sector in the economy is considered as a competitor to the private sector. The aim of this study is to investigate whether the government could have had an impact on employment in Iran during 1970-2011. Since identifying short and long-term relationships in this research is important, therefore, necessary analysis is performed by ARDL model analysis, using Eviews Software. The results show that government size has a positive impact on employment in short-term and long-term