Motion estimation and CABAC VLSI co-processors for real-time high-quality H.264/AVC video coding

Real-time and high-quality video coding is gaining a wide interest in the research and industrial community for different applications. H.264/AVC, a recent standard for high performance video coding, can be successfully exploited in several scenarios including digital video broadcasting, high-definition TV and DVD-based systems, which require to sustain up to tens of Mbits/s. To that purpose this paper proposes optimized architectures for H.264/AVC most critical tasks, Motion estimation and context adaptive binary arithmetic coding. Post synthesis results on sub-micron CMOS standard-cells technologies show that the proposed architectures can actually process in real-time 720 × 480 video sequences at 30 frames/s and grant more than 50 Mbits/s. The achieved circuit complexity and power consumption budgets are suitable for their integration in complex VLSI multimedia systems based either on AHB bus centric on-chip communication system or on novel Network-on-Chip (NoC) infrastructures for MPSoC (Multi-Processor System on Chip

Correlation effects in quasi one dimensional electron wires

We explore the role of electron correlation in quasi one dimensional quantum wires as the range of the interaction potential is changed and their thickness is varied by performing exact quantum Monte Carlo simulations at various electronic densities. In the case of unscreened interactions with a long range 1/x tail there is a crossover from a liquid to a quasi Wigner crystal state as the density decreases. When this interaction is screened, quasi long range order is prevented from forming, although a significant correlation with 4 k_F periodicity is still present at low densities. At even lower electron concentration, exchange is suppressed and the spin-dependent interactions become negligible, making the electrons behave like spinless fermions. We show that this behavior is shared by the long range and screened interactions by studying the spin and charge excitations of the system in both cases. Finally, we study the effect of electron correlations in the double quantum wire experiment [Steinberg et al., Phys. Rev. B 77, 113307 (2006)], by introducing an accurate model for the screening in the experiment and explicitly including the finite length of the system in our simulations. We find that decreasing the electron density drives the system from a liquid to a state with quite strong 4 k_F correlations. This crossover takes place around $20 \mu m^{-1}$, the density where the electron localization occurs in the experiment. The charge and spin velocities are also in remarkable agreement with the experimental findings in the proximity of the crossover. We argue that correlation effects play an important role at the onset of the localization transition.Comment: minor improvements, 13 pages, 12 figure

Linee guida per la programmazione remota e lo scarico dati di ricevitori GPS (Standard Trimble Navigation Limited - Serie 5000).

Nella fase di implementazione dell'hardware e del software per la materializzazione di stazioni GPS permanenti il problema della programmazione e scarico dati a distanza mediante modem da telefonia fissa, PSTN e ISDN o mediante modem da telefonia mobile, essenzialmente GSM /GPRS costituisce un problema di non facile soluzione. Anche laddove esista da parte delle aziende coinvolte nelle forniture un assistenza software che consenta di sviluppare dei prodotti personalizzati, alcune operazioni richieste vengono spesso eseguite dall'utenza con mezzi propri. Infatti, gli standard commerciali che vanno per la maggiore operano prevalentemente in ambiente Microsoft Windows e sono spesso privi della modularità e della flessibilità necessarie sia per adattarsi a problemi scientifici sia per la loro esecuzione in background in ambienti Unix (Linux, Solaris o HP-UX). In questo lavoro vengono analizzate le problematiche legate alla programmazione di ricevitori Trimble Navigation Limited modello 5700 CORS (Continuous Operating Reference Stations), in dotazione al Laboratorio di Geodesia e Telerilevamento dell'INGV-CNT, per un loro utilizzo nell’ambito di stazioni GPS permanenti. In particolare, è stato sviluppato un sistema automatico per il controllo a distanza, la programmazione e lo scarico dati di uno standard dei predetti ricevitori. Tutta la logistica della cascata hardware e dello strato software è stata sviluppata mediante strumenti da noi implementati; il risultato è sufficientemente stabile e può essere fattivamente utilizzato per il supporto alla realizzazione di stazioni permanenti GPS anche in siti dalla logistica scarsa come quelli situati in zone remote prive di linee telefoniche fisse e di alimentazione. Per il suddetto tipo di strumentazione infatti, non esiste in Italia una vera e propria assistenza Hardware e Software in grado di risolvere determinati problemi e, pertanto, in alcuni casi è stato necessario ricorrere sia al supporto tecnico dell'UNAVCO, il consorzio universitario Americano per il NAVSTAR GPS (http://www.unavco.org), sia alla nostra consolidata esperienza nel campo della strumentazione GPS. Il presente documento è rivolto ad un pubblico limitato costituito da quegli esperti del settore che siano interessati alla soluzione delle problematiche analizzate in questa sede

Electromagnetic analysis and performance comparison of fully 3D-printed antennas

In this work, the possibility of directly prototyping antennas by exploiting additive manufacturing 3D-printing technology is investigated. In particular, the availability of printable filaments with interesting conductive properties allows for printing of even the antenna conductive elements. Three samples of a 2.45 GHz microstrip patch antenna have been 3D-printed by using different approaches and materials, and their performance evaluated and compared. In particular, the same dielectric substrate printed in polylactic acid (PLA) has been adopted in all cases, whilst copper tape and two different conductive filaments have been used to realize the conductive parts of the three antenna samples, respectively. Even if an expected radiation efficiency reduction has been observed for the conductive filament case, the comparative analysis clearly demonstrates that 3D-printing technology can be exploited to design working fully-printed antennas, including the conductive parts

Does off-pump coronary revascularization confer superior organ protection in re-operative coronary artery surgery? A meta-analysis of observational studies

Off-pump coronary artery bypass surgery (OPCAB) has been hypothesised to be beneficial in the high-risk patient population undergoing re-operative coronary artery bypass graft surgery (CABG). In addition, this technique has been demonstrated to provide subtle benefits in end-organ function including heart, lungs and kidney. The aims of this study were to assess whether OPCAB is associated with a lower incidence of major adverse cardiovascular and cerebrovascular events (MACCE) and other adverse outcomes in re-operative coronary surgery. Twelve studies, incorporating 3471 patients were identified by systematic literature review. These were meta-analysed using random-effects modelling. Primary endpoints were MACCE and other adverse outcomes including myocardial infarction, stroke, renal dysfunction, low cardiac output state, respiratory failure and atrial fibrillation. A significantly lower incidence of myocardial infarction, stroke, renal dysfunction, low cardiac output state, respiratory failure and atrial fibrillation was observed with OPCAB (OR 0.58; 95% CI (confidence interval) [0.39-0.87]; OR 0.37; 95% CI [0.17-0.79]; OR 0.39; 95% CI [0.24-0.63]; OR 0.14; 95% CI [0.04-0.56]; OR 0.36; 95% CI [0.24-0.54]; OR 0.41; 95% CI [0.22-0.77] respectively). Sub-group analysis using sample size, matching score and quality score was consistent with and reflected these significant findings. Off-pump coronary artery bypass grafting reduces peri-operative and short-term major adverse outcomes in patients undergoing re-operative surgery. Consequently we conclude that OPCAB provides superior organ protection and a safer outcome profile in re-operative CABG

Efficacy of non-surgical periodontal therapy in reducing periodontal indexes in kidney-transplant patients

Efficacy of non-surgical periodontal therapy in reducing periodontal indexes in kidney-transplant patients. I. Casula, L. Zanardini*, M. Bianchi, V. Spotti, E. Marchesini Department of Medical and Surgical Specialties and Public Health Dentale - Dental School – University of Brescia, Italy Aim: kidney-transplant patient must take cyclosporine-A and calcium channel blockers chronically. Both medicines involve a gingival overgrowth (G.O.) as a collateral effect and this is due to their dosage: it appears 1-3 months after the beginning of the therapy. The prevalence of the G.O. is 84%. The G.O. originates from anterior interdental papilla and it appears as a red and soft tumefaction, that becomes more fibrinous as time goes by. The G.O. takes place in apical-coronal verse and also in vestibular-lingual verse and it looks like a gingival hypertrophy and hyperplasia, which is due to an abnormal increase of the number of fibroblasts into gingival connective tissue. The G.O. involves a great aggregation of extracellular Matrix, or less degradation of it, or both these processes simultaneously. The G.O. leads to the formation of pseudopockets, which interfere with the correct oral hygiene practices. This condition gives rise to mature plaque retention , that leads to infection, inflammation and the increase of the G.O. This condition becomes worse because of bad pre-transplant oral hygiene state. The aim of this study is to estimate the efficacy of non-surgical periodontal therapy in reducing the G.O. in kidney-transplant patient. Materials and methods: a sample of 32 simple random kidney transplant subjects was enrolled in this study (mean age: 58,44; range: 33-81, 21 m., 11f.). All of them were taking cyclosporine A and calcium channel blockers. Patients taking idantoine, pregnant women, patients suffering from diabetes mellitus or people who have undergone gingival surgery were excluded. The study started on November 2012 and finished on September 2013. Periodontal indexes and Professional oral hygiene practices were performed by the same dental hygienist. The plaque, calculus, bleeding, G.O. and probing depth indexes were evaluated at T0, T1, T2, T3 (at 0, 2, 4, 6 months respectively). Every time the same oral hygiene protocol was applied: non-surgical periodontal therapy with ultrasonic instruments above and below the gum. Results: 787 teeth analysed and 4722 periodontal sites probed. Plaque index (PI), calculus index (CI) and bleeding index (BoP) show significant statistical reduction (p<0,0001). T-test was used for statistic analysis. PI at T0=82,09%, at T3=29,89%/ CI at T0=53,44%, at T3=23,70%/ BoP at T0=71,98%, at T3=26,18%. Probing depth (PD), at six-monthly control , shows a significant statistical reduction (p<0,0001). PD 1-3 mm at T0=16,58%, at T3=30,45%. PD 4-6mm at T0=74,06%, at T3=64,70%. PD 7-9 mm at T0=9,36%, at T3=4,85%. G.O. At T0=54,93%, at T3=44,98%, with a significant statistical reduction (p<0,0001). Conclusions: the applied oral hygiene protocol is simple but effective in reducing drug-induced gingival overgrowth in kidney-transplant patient taking Cyclosporine-A. These clinic results assure a better oral health, improving the quality of life form an aesthetic and functional point of view

Low-energy models for correlated materials: bandwidth renormalization from Coulombic screening

We provide a prescription for constructing Hamiltonians representing the low energy physics of correlated electron materials with dynamically screened Coulomb interactions. The key feature is a renormalization of the hopping and hybridization parameters by the processes that lead to the dynamical screening. The renormalization is shown to be non-negligible for various classes of correlated electron materials. The bandwidth reduction effect is necessary for connecting models to materials behavior and for making quantitative predictions for low-energy properties of solids.Comment: 4 pages, 2 figure

Fingerprint Adversarial Presentation Attack in the Physical Domain

With the advent of the deep learning era, Fingerprint-based Authentication Systems (FAS) equipped with Fingerprint Presentation Attack Detection (FPAD) modules managed to avoid attacks on the sensor through artificial replicas of fingerprints. Previous works highlighted the vulnerability of FPADs to digital adversarial attacks. However, in a realistic scenario, the attackers may not have the possibility to directly feed a digitally perturbed image to the deep learning based FPAD, since the channel between the sensor and the FPAD is usually protected. In this paper we thus investigate the threat level associated with adversarial attacks against FPADs in the physical domain. By materially realising fakes from the adversarial images we were able to insert them into the system directly from the “exposed” part, the sensor. To the best of our knowledge, this represents the first proof-of-concept of a fingerprint adversarial presentation attack. We evaluated how much liveness score changed by feeding the system with the attacks using digital and printed adversarial images. To measure what portion of this increase is due to the printing itself, we also re-printed the original spoof images, without injecting any perturbation. Experiments conducted on the LivDet 2015 dataset demonstrate that the printed adversarial images achieve ∼ 100% attack success rate against an FPAD if the attacker has the ability to make multiple attacks on the sensor (10) and a fairly good result (∼ 28%) in a one-shot scenario. Despite this work must be considered as a proof-of-concept, it constitutes a promising pioneering attempt confirming that an adversarial presentation attack is feasible and dangerous

Dynamical screening in strongly correlated metal SrVO3

The consequences of dynamical screening of Coulomb interaction among correlated electrons in realistic materials have not been widely considered before. In this letter we try to incorporate a frequency dependent Coulomb interaction into the state-of-the-art ab initio electronic structure computing framework of local density approximation plus dynamical mean-field theory, and then choose SrVO3 as a prototype material to demonstrate the importance of dynamical screening effect. It is shown to renormalise the spectral weight near the Fermi level, to increase the effective mass, and to suppress the t2g quasiparticle band width apparently. The calculated results are in accordance with very recent angle-resolved photoemission spectroscopy experiments and Bose factor ansatz calculations.Comment: 6 pages, 4 figures. arXiv admin note: text overlap with arXiv:1107.312