Model Order Selection Rules For Covariance Structure Classification

The adaptive classification of the interference covariance matrix structure for radar signal processing applications is addressed in this paper. This represents a key issue because many detection architectures are synthesized assuming a specific covariance structure which may not necessarily coincide with the actual one due to the joint action of the system and environment uncertainties. The considered classification problem is cast in terms of a multiple hypotheses test with some nested alternatives and the theory of Model Order Selection (MOS) is exploited to devise suitable decision rules. Several MOS techniques, such as the Akaike, Takeuchi, and Bayesian information criteria are adopted and the corresponding merits and drawbacks are discussed. At the analysis stage, illustrating examples for the probability of correct model selection are presented showing the effectiveness of the proposed rules

The Friedmann-Lemaitre-Robertson-Walker Big Bang singularities are well behaved

We show that the Big Bang singularity of the Friedmann-Lemaitre-Robertson-Walker model does not raise major problems to General Relativity. We prove a theorem showing that the Einstein equation can be written in a non-singular form, which allows the extension of the spacetime before the Big Bang. The physical interpretation of the fields used is discussed. These results follow from our research on singular semi-Riemannian geometry and singular General Relativity.Comment: 10 pages, 5 figure

In partnerships we trust: NGO-donor relations. A case study of Romanian civil society support and development NGOs

In Romania, as in other Eastern European countries, the non-profit sector developed with funds and expertise from international donor organizations. This paperconsiders the relationship between non-profit organizations and their sponsors; particularly the influence funding has had on the structure of the former and their peer partnerships. To develop, NGOs have had to build a funding record; consequently, they have put a strong emphasis on the vertical relationship with their donors and the requirements of the latter for funding. Competitions to secure funding, access to specific know-how, the consolidation of the grants’ market have had a bearing on peer networks between non-profits. Ultimately, NGOs have been left with the difficult task of having to navigate between a pragmatic approach, to stay active in the sector, and their mission, to support the development of civil society

The impact of an educational program in the management of patients with chronic hepatitis C

Introduction: This study was designed to measure the impact of lifestyle changes, involving a diet therapy and physical exercises in patients with chronic hepatitis C (CHC). Methods: The study was conducted during January 2008 - December 2009 at ”Prof. N. Paulescu” National Institute of Diabetes, Nutrition and Metabolic Diseases - Bucharest, Romania. We selected 67 patients (34 men/33 women). We performed anthropometric measurements (weight, height, BMI (body mass index), bioimpedance analysis (BIA) as well as fasting serum lipids (cholesterol, triglycerides, HDL-cholesterol), glucose profile (glucose, HbA1c), liver profile (ALT, AST, GGT, alkaline phosphatase, bilirubin, albumin, total protein), blood count for all patients at baseline. Results: The average age was 53.91±10.19 years. Obesity was present in 32.8% (n=22) of patients at baseline. Total fat mass decreased with weight loss 2.21 kg (p = 0.0001) respectively 3.17 kg (p = 0.0001). Weight loss was accompanied by decreased resting energy expenditure. Triglycerides decreased from 158.11±7.63 mg/dl to 134.88±6.1 mg/dl, cholesterol decreased from 187.3±6.8 mg/dl to 168.65±4.42 mg/dl and HDL-cholesterol increased from 45.13±1.9 mg/dl to 47.2±1.39 mg/dl after 12 months. Aspartaminotransferase, alaninaminotransferese, gamma-glutamil transpeptidase decreased with significant differences. Conclusions: Patients with hepatitis C undergoing an 1-year lifestyle intervention had significant improvements in fasting glucose, fasting insulin, HOMA-IR, lipidic profile, hepatic profile and adipose tissue distribution. The present study establishes the positive impact of an educational program in the management of patients with hepatitis C

Taxi Planner Optimization: A Management Tool

This work introduces taxi planning optimization (TPO) as a methodology to guide airport surface management operations. The optimization model represents competing aircraft using limited ground resources. TPO improves aircraft taxiing routes and their schedule in situations of congestion, minimizing overall taxiing time (TT), and helping taxi planners to meet prespecified goals such as compliance with take-off windows, TT limits, and trajectory conflicts. By considering all simultaneous trajectories during a given planning horizon, TPO's estimation of TT from the stand to the runways improves over current planning methods. The operational optimization model is a large-scale space-time multi-commodity network with capacity constraints. In addition to its natural use as a real-time taxi planning tool, a number of TPO variants can be used for design purposes, such as expansion of new infrastructure. TPO is demonstrated using Madrid-Barajas as test airport

An integrative approach based on probabilistic modelling and statistical inference for morpho-statistical characterization of astronomical data

This paper describes several applications in astronomy and cosmology that are addressed using probabilistic modelling and statistical inference

The High-Flux Backscattering Spectrometer at the NIST Center for Neutron Research

We describe the design and current performance of the high-flux backscattering spectrometer located at the NIST Center for Neutron Research. The design incorporates several state-of-the-art neutron optical devices to achieve the highest flux on sample possible while maintaining an energy resolution of less than 1mueV. Foremost among these is a novel phase-space transformation chopper that significantly reduces the mismatch between the beam divergences of the primary and secondary parts of the instrument. This resolves a long-standing problem of backscattering spectrometers, and produces a relative gain in neutron flux of 4.2. A high-speed Doppler-driven monochromator system has been built that is capable of achieving energy transfers of up to +-50mueV, thereby extending the dynamic range of this type of spectrometer by more than a factor of two over that of other reactor-based backscattering instruments

Fully-Renormalized QRPA fulfills Ikeda sum rule exactly

The renormalized quasiparticle-RPA is reformulated for even-even nuclei using restrictions imposed by the commutativity of the phonon creation operator with the total particle number operator. This new version, Fully-Renormalized QRPA (FR-QRPA), is free from the spurious low-energy solutions. Analytical proof is given that the Ikeda sum rule is fullfiled within the FR-QRPA.Comment: 9 page

Isospin Character of the Pygmy Dipole Resonance in 124Sn

The pygmy dipole resonance has been studied in the proton-magic nucleus 124Sn with the (a,a'g) coincidence method at E=136 MeV. The comparison with results of photon-scattering experiments reveals a splitting into two components with different structure: one group of states which is excited in (a,a'g) as well as in (g,g') reactions and a group of states at higher energies which is only excited in (g,g') reactions. Calculations with the self-consistent relativistic quasiparticle time-blocking approximation and the quasiparticle phonon model are in qualitative agreement with the experimental results and predict a low-lying isoscalar component dominated by neutron-skin oscillations and a higher-lying more isovector component on the tail of the giant dipole resonance