Network traffic prediction based on a new time series model

Fast and accurate methods for predicting traffic properties and trend are essential for dynamic network resource management and congestion control. With the aim of performing online and feasible prediction of network traffic, this paper proposes a novel time series model, named adaptive autoregressive (AAR). This model is built upon an adaptive memory‐shortening technique and an adaptive‐order selection method originally developed by this study. Compared to the conventional one‐step ahead prediction using traditional Box–Jenkins time series models (e.g. AR, MA, ARMA, ARIMA and ARFIMA), performance results obtained from actual Internet traffic traces have demonstrated that the proposed AAR model is able to support online prediction of dynamic network traffic with reasonable accuracy and relatively low computation complexity. Copyright © 2005 John Wiley & Sons, Ltd.     

Polymer stain resistance: Prediction versus experiment

The coloration of different polymer films (from commodity and packaging films to performance films) by contact with various food coloring substances was evaluated. For this purpose, both solubility parameters as a prediction tool, and immersion experiments for time range between 24 and 1000 h were established. The two predicting tools are the Hoy and Hoftyzer‐Van Krevelen (HVK) methods. For PE and PP, HVK's method is preferred for predicting coloration. Neither of the HVK's and Hoy's methods was able to establish a coloration prediction for PET while both methods could predict the staining of PEEK. The coloration of partially and fully fluorinated polymers is well predicted by the Hoy's method. The behavior of PP/PA and PP/PA/PP multilayer films was also studied. Crystallinity degree of polymers, temperature and concentration of coloring molecules are also important parameters, which are not taken into account in solubility theories. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Degradation of C.I. Acid Orange 7 by heterogeneous Fenton oxidation in combination with ultrasonic irradiation

BACKGROUND: A mesoporous alumina supported nanosized Fe₂O₃ was prepared through an original synthesis procedure and used as a heterogeneous catalyst for the Fenton process degradation of the model azo dye C.I. Acid Orange 7 enhanced by ultrasound irradiation (US/Fe₂O₃‐Al₂O₃‐meso/H₂O₂ system). The effect of various operating conditions was investigated, namely hydrogen peroxide concentration, initial pH, ultrasonic power and catalyst loading. RESULTS: The results indicated that the degradation of C.I. Acid Orange 7 followed a pseudo‐first‐order kinetic model. There exists an optimal hydrogen peroxide concentration, initial pH, ultrasonic power and catalyst loading for decolorization. The aggregate size of the spent catalyst was reduced after dispersion in water by ultrasonic irradiation. A very low level of iron leaching was observed ranging from < 0.1 to 0.23 mg L^?1. The intermediate products of C.I. Acid Orange 7 degradation were identified using gas chromatography–mass spectrometry (GC‐MS). CONCLUSION: The optimal conditions for efficient C.I. Acid Orange 7 degradation were pH close to 3, hydrogen peroxide concentration 4 mmol L^?1, catalyst loading 0.3 g L^?1, and ultrasonic power 80 W. Copyright © 2011 Society of Chemical Industry     

An Overview and Future Perspectives of Aluminum Batteries

A critical overview of the latest developments in the aluminum battery technologies is reported. The substitution of lithium with alternative metal anodes characterized by lower cost and higher abundance is nowadays one of the most widely explored paths to reduce the cost of electrochemical storage systems and enable long‐term sustainability. Aluminum based secondary batteries could be a viable alternative to the present Li‐ion technology because of their high volumetric capacity (8040 mAh cm^?3 for Al vs 2046 mAh cm^?3 for Li). Additionally, the low cost aluminum makes these batteries appealing for large‐scale electrical energy storage. Here, we describe the evolution of the various aluminum systems, starting from those based on aqueous electrolytes to, in more details, those based on non‐aqueous electrolytes. Particular attention has been dedicated to the latest development of electrolytic media characterized by low reactivity towards other cell components. The attention is then focused on electrode materials enabling the reversible aluminum intercalation‐deintercalation process. Finally, we touch on the topic of high‐capacity aluminum‐sulfur batteries, attempting to forecast their chances to reach the status of practical energy storage systems.     

Genomic Instability Is an Early Event in Aluminium-Induced Tumorigenesis

Genomic instability is generally considered as a hallmark of tumorigenesis and a prerequisite condition for malignant transformation. Aluminium salts are suspected environmental carcinogens that transform mammary epithelial cells in vitro through unknown mechanisms. We report here that long-term culture in the presence of aluminium chloride (AlCl₃) enables HC11 normal mouse mammary epithelial cells to form tumours and metastases when injected into the syngeneic and immunocompetent BALB/cByJ strain. We demonstrate that AlCl₃ rapidly increases chromosomal structural abnormalities in mammary epithelial cells, while we failed to detect direct modulation of specific mRNA pathways. Our observations provide evidence that clastogenic activity—a well-recognized inducer of genomic instability—might account in part for the transforming abilities of aluminium in mammary epithelial cells.     

The First European Parabolic Flight Campaign with the Airbus A310 ZERO-G

Aircraft parabolic flights repetitively provide up to 23 seconds of reduced gravity during ballistic flight manoeuvres. Parabolic flights are used to conduct short microgravity investigations in Physical and Life Sciences and in Technology, to test instrumentation prior to space flights and to train astronauts before a space mission. The use of parabolic flights is complementary to other microgravity carriers (drop towers, sounding rockets), and preparatory to manned space missions on board the International Space Station and other manned spacecraft, such as Shenzhou and the future Chinese Space Station. After 17 years of using the Airbus A300 ZERO-G, the French company Novespace, a subsidiary of the ’Centre National d’Etudes Spatiales’ (CNES, French Space Agency), based in Bordeaux, France, purchased a new aircraft, an Airbus A310, to perform parabolic flights for microgravity research in Europe. Since April 2015, the European Space Agency (ESA), CNES and the ‘Deutsches Zentrum für Luft- und Raumfahrt e.V.’ (DLR, the German Aerospace Center) use this new aircraft, the Airbus A310 ZERO-G, for research experiments in microgravity. The first campaign was a Cooperative campaign shared by the three agencies, followed by respectively a CNES, an ESA and a DLR campaign. This paper presents the new Airbus A310 ZERO-G and its main characteristics and interfaces for scientific experiments. The experiments conducted during the first European campaign are presented.     

A novel target detection algorithm combining foreground and background manifold-based models

This paper focuses on the detection of small objects—more precisely on vehicles in aerial images—on complex backgrounds such as natural backgrounds. A key contribution of the paper is to show that, in such situations, learning a target model and a background model separately is better than training a unique discriminative model. This contrasts with standard object detection approaches for which objects vs. background classifiers use the same model as well as the same types of visual features for both. The second contribution lies in the manifold learning approach introduced to build these models. The proposed detection algorithm is validated on the publicly available OIRDS dataset, on which we obtain state-of-the-art results.     

Slot antenna array synthesis using the infinitesimal dipole model technique: Theory and experiment

The present article proposes and validates a new general design methodology that can be used to automatically find proper positions and orientations of waveguide‐based radiating slots capable of realizing any given radiation beam profile. The new technique combines basic radiation theory and waveguide propagation theory in an analytical model that permits the prediction of the radiation characteristics of generic slots without the need to perform full‐wave numerical solution while completely avoiding using transmission‐line models or the slot impedance method. The analytical model is then used to implement a low‐cost objective function within a global optimization scheme and subsequently deployed to find optimum positions and orientations of clusters of radiating slots cut into the waveguide surface such that any desired beam pattern can be obtained, leading to very efficient and robust beamforming capability that can be applied to dynamic beamforming in real‐time scenarios like MIMO systems. The proposed design method is verified using both full‐wave numerical solution and experiment.     

Synthesis and characterization of a water-soluble rigid-rod polymer

Water-soluble polyaramides have been prepared from 2,5-diaminobenzene-sulphonic-acid activated by TMSCl and terephthalic-acid-chloride. Using this method, we achieved molecular weights of our polymers up to 18,000 g mol⁻¹. Two model compounds were synthesized in order to establish the effect of trimethylsilyl-chloride, which was used as the activating agent for this reaction. The resulting sulphonated poly-aramides were characterized by: inherent viscosity measurements, size exclusion chromatography (SEC), DMA, TGA, flame absorbance atomic spectroscopy (FAAS), NMR spectroscopy and optical polarisation microscopy. In all cases, the polymers were easily soluble in hot water up to concentrations of 20 wt%. Upon cooling lyotropic alignment of molecular aggregates is observed at low polymer concentrations, typically 2–5 wt%. Polymers with low molecular weights do not show this behaviour. Films made from these sulphonated aramide polymers showed good thermal stability, and have interesting mechanical properties. Our results indicate the presence of a structure consisting of molecular aggregates.     

Flying Cities: building a 3D world from vocal input

Abstract

Flying Cities is an artistic installation which generates imaginary cities from the speech of its visitors. Thanks to an original interactive process analysing people's vocal input to create 3D graphics, a tangible correspondence between speech and visuals opens new possibilities of interaction. This cross-modal interaction not only supports our artistic messages, but also aims at providing anyone with a pleasant and stimulating feedback from her/his speech activity. As the feedback we have received when presenting Flying Cities was very positive, our objective is now to cross the bridge between art and a potential application. We believe that it could become a new medium for creativity and a way to visually perceive a vocal performance in the context of the rehabilitation of people with reduced mobility or language impairments.