43 research outputs found

    Hybrid image representation methods for automatic image annotation: a survey

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    In most automatic image annotation systems, images are represented with low level features using either global methods or local methods. In global methods, the entire image is used as a unit. Local methods divide images into blocks where fixed-size sub-image blocks are adopted as sub-units; or into regions by using segmented regions as sub-units in images. In contrast to typical automatic image annotation methods that use either global or local features exclusively, several recent methods have considered incorporating the two kinds of information, and believe that the combination of the two levels of features is beneficial in annotating images. In this paper, we provide a survey on automatic image annotation techniques according to one aspect: feature extraction, and, in order to complement existing surveys in literature, we focus on the emerging image annotation methods: hybrid methods that combine both global and local features for image representation

    Efficient Implementation on Low-Cost SoC-FPGAs of TLSv1.2 Protocol with ECC_AES Support for Secure IoT Coordinators

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    Security management for IoT applications is a critical research field, especially when taking into account the performance variation over the very different IoT devices. In this paper, we present high-performance client/server coordinators on low-cost SoC-FPGA devices for secure IoT data collection. Security is ensured by using the Transport Layer Security (TLS) protocol based on the TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 cipher suite. The hardware architecture of the proposed coordinators is based on SW/HW co-design, implementing within the hardware accelerator core Elliptic Curve Scalar Multiplication (ECSM), which is the core operation of Elliptic Curve Cryptosystems (ECC). Meanwhile, the control of the overall TLS scheme is performed in software by an ARM Cortex-A9 microprocessor. In fact, the implementation of the ECC accelerator core around an ARM microprocessor allows not only the improvement of ECSM execution but also the performance enhancement of the overall cryptosystem. The integration of the ARM processor enables to exploit the possibility of embedded Linux features for high system flexibility. As a result, the proposed ECC accelerator requires limited area, with only 3395 LUTs on the Zynq device used to perform high-speed, 233-bit ECSMs in 413 ”s, with a 50 MHz clock. Moreover, the generation of a 384-bit TLS handshake secret key between client and server coordinators requires 67.5 ms on a low cost Zynq 7Z007S device

    Ontology-based semantic classification of satellite images: Case of major disasters

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    The International Charter 'Space and Major Disasters' is regularly activated during a catastrophic event and offers rescue teams comprehensive damage maps. Most of these maps are built by means of satellite image manual processing, which is often complex and demanding in terms of time and energy. Automatic processing supplies prompt treatment. Nevertheless, it usually presents a semantic gap handicap. The exploitation of ontologies to bridge the semantic gap has been widely recommended due to their quality of knowledge representation, expression, and discovery. In this work, we present an ontology-based semantic hierarchical classification method to undertake this problem. Ontology components are translated to image-based parameters and exploited to assist the classification process at two levels, and using 12 classes. The region of interest is selected from the first level and exhaustively analyzed and classified at the second level. The 2010 Haiti earthquake was selected as study area for this work. Experiments were performed using very high resolution multi-temporal QuickBird imagery and eCognition software

    Pour une meilleure efficacité énergétique dans un systÚme Smart Grid - Cloud

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    This thesis considers the energy efficiency of information and communication infrastructures in a smart grid - cloud system. It especially deals with communication networks and cloud data centers due to their high energy consumption, which confers them an important role in the network. The contributions of this thesis are implemented on the same framework integrating the smart grid, microgrid, cloud, data centers and users. Indeed, we have studied the interaction between the cloud data centers and the smart grid provider and we have proposed energy efficient power allocation solutions and an energy cost minimization scheme using two architectures: a smart grid-cloud architecture and a microgrid-cloud architecture. In addition, we paid close attention to execute user requests while ensuring a good quality of service in a fog-cloud architecture. In comparison with state-of-the-art works, the results of our contributions have shown that they respond to the identified challenges, particularly in terms of reducing carbon emissions and energy costs of cloud data centers.Dans cette thĂšse, nous Ă©tudions l’efficacitĂ© Ă©nergĂ©tique des infrastructures informatiques dans un systĂšme smart grid – cloud. Nous nous intĂ©ressons plus particuliĂšrement aux rĂ©seaux de communication et aux data centers du cloud. Nous nous focalisons sur ces derniers Ă  cause de leur grande consommation d’énergie et du rĂŽle vital qu’ils jouent dans un monde connectĂ© en pleine expansion, les positionnant, ainsi, comme des Ă©lĂ©ments importants dans un systĂšme smart grid - cloud. De ce fait, les travaux de cette thĂšse s’inscrivent dans le cadre d’un seul framework intĂ©grant le smart grid, le microgrid, le cloud, les data centers et les utilisateurs. Nous avons, en effet, Ă©tudiĂ© l’interaction entre les data centers du cloud et le fournisseur d’énergie du smart grid et nous avons proposĂ© des solutions d’allocation d’énergie et de minimisation du coĂ»t d’énergie en utilisant deux architectures : (1) une architecture smart grid-cloud et (2) une architecture microgrid-cloud. Par ailleurs, nous avons portĂ© une attention particuliĂšre Ă  l’exĂ©cution des requĂȘtes des utilisateurs tout en leur garantissant un niveau de qualitĂ© de service satisfaisant dans une architecture fog -cloud. En comparaison avec les travaux de l’état de l’art, les rĂ©sultats de nos contributions ont montrĂ© qu’ils rĂ©pondent aux enjeux identifiĂ©s, notamment en rĂ©duisant les Ă©missions de gaz Ă  effet de serre et le coĂ»t d’énergie des data centers

    For better energy efficiency in a Smart Grid – Cloud system

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    Dans cette thĂšse, nous Ă©tudions l’efficacitĂ© Ă©nergĂ©tique des infrastructures informatiques dans un systĂšme smart grid – cloud. Nous nous intĂ©ressons plus particuliĂšrement aux rĂ©seaux de communication et aux data centers du cloud. Nous nous focalisons sur ces derniers Ă  cause de leur grande consommation d’énergie et du rĂŽle vital qu’ils jouent dans un monde connectĂ© en pleine expansion, les positionnant, ainsi, comme des Ă©lĂ©ments importants dans un systĂšme smart grid - cloud. De ce fait, les travaux de cette thĂšse s’inscrivent dans le cadre d’un seul framework intĂ©grant le smart grid, le microgrid, le cloud, les data centers et les utilisateurs. Nous avons, en effet, Ă©tudiĂ© l’interaction entre les data centers du cloud et le fournisseur d’énergie du smart grid et nous avons proposĂ© des solutions d’allocation d’énergie et de minimisation du coĂ»t d’énergie en utilisant deux architectures : (1) une architecture smart grid-cloud et (2) une architecture microgrid-cloud. Par ailleurs, nous avons portĂ© une attention particuliĂšre Ă  l’exĂ©cution des requĂȘtes des utilisateurs tout en leur garantissant un niveau de qualitĂ© de service satisfaisant dans une architecture fog -cloud. En comparaison avec les travaux de l’état de l’art, les rĂ©sultats de nos contributions ont montrĂ© qu’ils rĂ©pondent aux enjeux identifiĂ©s, notamment en rĂ©duisant les Ă©missions de gaz Ă  effet de serre et le coĂ»t d’énergie des data centers.This thesis considers the energy efficiency of information and communication infrastructures in a smart grid - cloud system. It especially deals with communication networks and cloud data centers due to their high energy consumption, which confers them an important role in the network. The contributions of this thesis are implemented on the same framework integrating the smart grid, microgrid, cloud, data centers and users. Indeed, we have studied the interaction between the cloud data centers and the smart grid provider and we have proposed energy efficient power allocation solutions and an energy cost minimization scheme using two architectures: a smart grid-cloud architecture and a microgrid-cloud architecture. In addition, we paid close attention to execute user requests while ensuring a good quality of service in a fog-cloud architecture. In comparison with state-of-the-art works, the results of our contributions have shown that they respond to the identified challenges, particularly in terms of reducing carbon emissions and energy costs of cloud data centers

    Pour une meilleure efficacité énergétique dans un systÚme Smart Grid - Cloud

    No full text
    This thesis considers the energy efficiency of information and communication infrastructures in a smart grid - cloud system. It especially deals with communication networks and cloud data centers due to their high energy consumption, which confers them an important role in the network. The contributions of this thesis are implemented on the same framework integrating the smart grid, microgrid, cloud, data centers and users. Indeed, we have studied the interaction between the cloud data centers and the smart grid provider and we have proposed energy efficient power allocation solutions and an energy cost minimization scheme using two architectures: a smart grid-cloud architecture and a microgrid-cloud architecture. In addition, we paid close attention to execute user requests while ensuring a good quality of service in a fog-cloud architecture. In comparison with state-of-the-art works, the results of our contributions have shown that they respond to the identified challenges, particularly in terms of reducing carbon emissions and energy costs of cloud data centers.Dans cette thĂšse, nous Ă©tudions l’efficacitĂ© Ă©nergĂ©tique des infrastructures informatiques dans un systĂšme smart grid – cloud. Nous nous intĂ©ressons plus particuliĂšrement aux rĂ©seaux de communication et aux data centers du cloud. Nous nous focalisons sur ces derniers Ă  cause de leur grande consommation d’énergie et du rĂŽle vital qu’ils jouent dans un monde connectĂ© en pleine expansion, les positionnant, ainsi, comme des Ă©lĂ©ments importants dans un systĂšme smart grid - cloud. De ce fait, les travaux de cette thĂšse s’inscrivent dans le cadre d’un seul framework intĂ©grant le smart grid, le microgrid, le cloud, les data centers et les utilisateurs. Nous avons, en effet, Ă©tudiĂ© l’interaction entre les data centers du cloud et le fournisseur d’énergie du smart grid et nous avons proposĂ© des solutions d’allocation d’énergie et de minimisation du coĂ»t d’énergie en utilisant deux architectures : (1) une architecture smart grid-cloud et (2) une architecture microgrid-cloud. Par ailleurs, nous avons portĂ© une attention particuliĂšre Ă  l’exĂ©cution des requĂȘtes des utilisateurs tout en leur garantissant un niveau de qualitĂ© de service satisfaisant dans une architecture fog -cloud. En comparaison avec les travaux de l’état de l’art, les rĂ©sultats de nos contributions ont montrĂ© qu’ils rĂ©pondent aux enjeux identifiĂ©s, notamment en rĂ©duisant les Ă©missions de gaz Ă  effet de serre et le coĂ»t d’énergie des data centers

    Apport de l'imagerie satellitale multi-résolution pour l'étude de la dynamique urbaine (le cas d'une ville en zone de transition montagne-plaine)

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    La présente thÚse porte sur l'apport de l'imagerie satellitale multi-résolution à la compréhension de la dynamique urbaine en zone de transition montagne-plaine ; le complexe urbain de Blida est pris comme zone d'étude. Le processus de détection des changements a été réalisé en plusieurs étapes dont : l'extraction de l'emprise urbaine et des réseaux routiers ; l'analyse de l'espace urbain par fusion d'informations spectrale et texturale ; le suivi de la dynamisue urbaine et péri-urbaine par intégration d'images multidates.The present thesis relates to the contribution of the multi-resolution satellitale imagery to comprehension of urban dynamics in zone of transition mountain-plain ; the urban complex of Blida is taken as zone of study. The process of detection of the changes was carried out in several steps of which : the extraction of the urban morphology and the roads networks ; the analysis of the urban space by fusion of spectral and textural information ; the follow up of it urban and peri-urban dynamics by integration of temporal images.PARIS12-CRETEIL BU Multidisc. (940282102) / SudocSudocAlgeriaFranceDZF

    Warehousing and analysing textual data

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