EARLY FOREST FIRE DETECTION USING TEXTURE, BLOB THRESHOLD, AND MOTION ANALYSIS OF PRINCIPAL COMPONENTS

Forest fires constantly threaten ecological systems, infrastructure and human lives. The purpose behind this study is minimizing the devastating damage caused by forest fires. Since it is impossible to completely avoid their occurrences, it is essential to accomplish a fast and appropriate intervention to minimize their destructive consequences. The most traditional method for detecting forest fires is human based surveillance through lookout towers. However, this study presents a more modern technique. It utilizes land-based real-time multispectral video processing to identify and determine the possibility of fire occurring within the camera’s field of view. The temporal, spectral, and spatial signatures of the fire are exploited. The methods discussed include: (1) Range filtering followed by entropy filtering of the infrared (IR) video data, and (2) Principal Component Analysis of visible spectrum video data followed by motion analysis and adaptive intensity threshold. The two schemes presented are tailored to detect the fire core, and the smoke plume, respectively. Cooled Midwave Infrared (IR) camera is used to capture the heat distribution within the field of view. The fire core is then isolated using texture analysis techniques: first, range filtering applied on two consecutive IR frames, and then followed by entropy filtering of their absolute difference. Since smoke represents the earliest sign of fire, this study also explores multiple techniques for detecting smoke plumes in a given scene. The spatial and temporal variance of smoke plume is captured using temporal Principal Component Analysis, PCA. The results show that a smoke plume is readily segmented via PCA applied on the visible Blue band over 2 seconds sampled every 0.2 seconds. The smoke plume exists in the 2nd principal component, and is finally identified, segmented, and isolated, using either motion analysis or adaptive intensity threshold. Experimental results, obtained in this study, show that the proposed system can detect smoke effectively at a distance of approximately 832 meters with a low false-alarm rate and short reaction time. Applied, such system would achieve early forest fire detection minimizing fire damage. Keywords: Image Processing, Principal Component Analysis, PCA, Principal Component, PC, Texture Analysis, Motion Analysis, Multispectral, Visible, Cooled Midwave Infrared, Smoke Signature, Gaussian Mixture Model

Etat Des Lieux De La Production De Sculptures Sur Bois Dans L’Atlantique Et Du Littoral Au Sud Du Benin

La sculpture sur bois est une activité artisanale qui se pratique dans certaines localités des départements de l’Atlantique et du Littoral au sud du Bénin. Son exercice, bien que pénible, continue de mobiliser quelques rares artisans passionnés. Malgré que cette activité soit progressivement délaissée, ses productions sont cependant d’un attrait pour les touristes. Pour la sauvegarde de cette activité, cette étude a visé à réaliser un état des lieux de sa pratique dans ces deux départements.L’approche méthodologique adoptée est axée sur la recherche documentaire, la collecte des données, leur traitement et l’analyse des résultats. La méthode de la boule de neige a permis d’enquêter 19 sculpteurs du bois de la zone d’étude. Les logiciels Excel, Sphinx Plus2 ont aidé au traitement des données.Les résultats obtenus de l’étude montrent que la sculpture sur bois continue à être pratiquée dans les départements de l’Atlantique et du Littoral. L’activité est favorisée par plusieurs facteurs. Il existe plusieurs espèces ligneuses permettant de disposer de bois variés. Ces départements disposent aussi d’une ressource humaine de qualité et d’expérience dans la sculpture du bois. Au plan technique et organisationnel, la mise en place par l’Etat du Fonds de Développement de l’Artisanat et l’institution du Certificat de Qualification aux Métiers (CQM) pour les artisans des différents corps de métiers en fin de formation au Bénin sont aussi d’un atout capital

Photovoltaic Forecasting: A state of the art

International audiencePhotovoltaic (PV) energy, together with other renewable energy sources, has been undergoing a rapid development in recent years. Integration of intermittent energy sources as PV or wind power is challenging in terms of power system management in large scale systems as well as in small grids. Indeed, PV energy is a variable resource that is difficult to predict due to meteorological uncertainty. To facilitate the penetration of PV energy, forecasting methods and techniques have been used. Being able to predict the future behavior of a PV plant is very important in order to schedule and manage the alternative supplies and the reserves. In this paper we presented an overview aiming at a classification attending to the different techniques of forecasting methods used for PV or solar prediction. Finally, recent new approaches that take into account the uncertainty of the estimation are introduced. First results of these kind of models are presented

Comparison of Efficacy and Ocular Surface Disease Index Score between Bimatoprost, Latanoprost, Travoprost, and Tafluprost in Glaucoma Patients

Aim. The purpose of this study is to evaluate and compare the efficacy of 4 prostaglandin analogues (PGAs) and to determine the incidence of ocular surface disease in newly diagnosed, primary open-angle glaucoma (POAG) patients started on one of those 4 PGAs: bimatoprost (benzalkonium chloride, BAK, 0.3 mg/mL), latanoprost (BAK 0.2 mg/mL), travoprost (polyquad), and tafluprost (BAK-free). Patients and Methods. In this single-center, open-label trial, 32 patients newly diagnosed with POAG were randomly started on one of the four PGAs. All patients underwent a complete ophthalmological exam at presentation and at 1, 3, and 6 months of follow-up. Dry eye disease (DED) was assessed using the original Ocular Surface Disease Index (OSDI) questionnaire, in order to evaluate the impact of the drops on the quality of life of patients. Results. The mean age was 60.06 years ± 11.76. All four drugs equally and significantly reduced the intraocular pressure (IOP) with respect to the baseline IOP. There was a trend for a slightly greater reduction of IOP with bimatoprost, but the difference was not found to be statistically significant when compared to other PGAs. OSDI scores were significantly superior for travoprost (10.68 ± 5.73) compared to the other three drugs (p<0.05). Latanoprost caused the most significant eyelash growth and iris discoloration. Conjunctival hyperemia and superficial keratitis occurrence were similar in the four groups. Conclusion. All prostaglandin analogues equally and significantly reduce the IOP in patients with POAG. According to the results of the OSDI score, latanoprost seems to be the least tolerated among the four drugs

Facile and sustainable synthesis of nitrogen-doped polymer and carbon porous spheres

International audienceThe development of green, sustainable and simple synthesis pathways for the design of polymer and carbonaceous materials with well controlled features is of great importance for many fields of applications. Herein, we report a green synthesis method for polymer and carbon particles with well-defined shape and size. This approach involves the use of green precursors, water as solvent, no templates 10 under ambient temperature and pressure conditions, simultaneously. Green polymer resins (phloroglucinol-glyoxylic acid) and a catalyst/nitrogen source (triethylenediamine) are dissolved in water at room temperature resulting in polymer particles which by subsequent thermal treatment transforms in carbon particles. Mainly spherical carbon particles with controlled size from 500 nm to 10 µm were obtained by simply adjusting the experimental conditions, i.e., the synthesis time and the molar ratio between the precursors or solvent. In some conditions, flower-like morphology was obtained as well. The synthesis mechanism from polymer resin spheres 15 formation to their conversion into carbon sphere was determined by several techniques, i.e., 13 C NMR spectroscopy, SEM, XPS and TPD-MS (temperature programmed desorption coupled by mass spectrometer). 2

Eco-Friendly Synthesis of Nitrogen-Doped Mesoporous Carbon for Supercapacitor Application

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Numerical modelling of a hemp concrete wall

In a global warming context associated to the abuse of energy consumption, actual researches focus more and more on reducing energy costs in the building sector. This target could be achieved by using innovative building materials, such as hemp concrete, due to its positive impacts on thermal and environmental levels. The aim of this work is to carry out a numerical study of a hemp concrete wall subjected to several indoor and outdoor conditions of temperature and relative humidity using the program object oriented SPARK. The hygrothermal behaviour of the wall is investigated taking into account heat and moisture transfer within the wall as well as hysteresis phenomenon between the sorption and desorption curves and their temperature dependency

Experimental investigation and modeling attempt on the effects of ultraviolet aging on the fatigue behavior of an LDPE semi-crystalline polymer

The objective of this study was to investigate the effect of UV irradiation on the fatigue life of a bulk semi-crystalline polymer. Low-density polyethylene samples exposed to different UV irradiation doses were fatigue tested. Fatigue indicator based on dissipated energy per cycle was found to present the best correlation with the experimental fatigue results. A master curve unifying the experimental fatigue results for as-received and UV-aged materials was obtained when subtracting the dissipated energy threshold from the total dissipated energy. Finally, the evolution of the damage with cyclic loading was analyzed and preliminary modeling was attempted.This research was supported by the Qatar National Research Fund (NPRP grant No. 7-1562-2-571). We would like to acknowledge the fruitful discussions with Profs. Eddine Gherdaoui and Jean-Michel Gloaguen of the University of Lille

New developments in fracture of rubbers: Predictive tools and influence of thermal aging

In this work, the influence of thermal oxidative aging on the ultimate mechanical properties of rubbers is investigated. Two new approaches to predict failure properties are proposed. The first one is the stress limiter approach that uses a “damage” parameter allowing determination of the failure stress and strain of an aged material knowing both the mechanical properties and macromolecular network characteristics of an as-received material. The second one is an extension of the energy limiter approach that suggests capturing the drop of the stress at failure by replacing the strain energy density function of an as-received elastomeric material by a function expressed in terms of an energy limiter. The predictive capabilities of these two approaches are validated using experimental results for two elastomeric materials: an EPDM and a polychloroprene (CR), both of which exhibit a largely predominant post-crosslinking (over chain scissions) during aging. Comparison between the predictions and the experimental results in terms of failure stresses and strains under uniaxial tension showed a good agreement. Consequently, these two approaches are promising tools for designing elastomeric parts subjected to thermal oxidative aging