Search results for " architect"
showing 10 items of 2719 documents
A Hierarchical Detection and Response System to Enhance Security Against Lethal Cyber-Attacks in UAV Networks
2018
International audience; Unmanned aerial vehicles (UAVs) networks have not yet received considerable research attention. Specifically, security issues are a major concern because such networks, which carry vital information, are prone to various attacks. In this paper, we design and implement a novel intrusion detection and response scheme, which operates at the UAV and ground station levels, to detect malicious anomalies that threaten the network. In this scheme, a set of detection and response techniques are proposed to monitor the UAV behaviors and categorize them into the appropriate list (normal, abnormal, suspect, and malicious) according to the detected cyber-attack. We focus on the m…
Utility-based resource allocations in multi-hop wireless networks
2011
It is well known that CSMA (Carrier Sense Multiple Access) protocols exhibit very poor performance in case of multi-hop transmissions, because of inter-link interference due to imperfect carrier sensing. Since ad-hoc networks based on multihop packet deliveries are becoming more and more common in different application and networking scenarios, different medium access control extensions are currently considered for improving the channel utilization efficiency. In this paper, we propose a simple approach based on preallocating temporal slots in which different sets of nodes are allowed to contend for the channel access, which can significantly improve CSMA performance with limited signaling …
Middleware with QoS Support to Control Intelligent Systems
2008
This paper presents the architecture of a middleware for control component-based distributed systems. The fundamental idea underlying this architecture is the use of a hierarchical communications structure called "logical namespace tree" and a structured set of control processes interconnected, called "logical sensors graph". This architecture is named frame sensor adapter control (FSA-Ctrl). The aim of FSA-Ctrl is to provide a simple interface to specify the control actions and ensure a communication with some specified QoS parameters restrictions. In this architecture both systems, communication and control, manages the QoS policies. The communication system is based on the data distribut…
An FPGA-Based Adaptive Fuzzy Coprocessor
2005
The architecture of a general purpose fuzzy logic coprocessor and its implementation on an FPGA based System on Chip is described. Thanks to its ability to support a fast dynamic reconfiguration of all its parameters, it is suitable for implementing adaptive fuzzy logic algorithms, or for the execution of different fuzzy algorithms in a time sharing fashion. The high throughput obtained using a pipelined structure and the efficient data organization allows significant increase of the computational capabilities strongly desired in applications with hard real-time constraints.
A distributed real-time data prediction and adaptive sensing approach for wireless sensor networks
2018
International audience; Many approaches have been proposed in the literature to reduce energy consumption in Wireless Sensor Networks (WSNs). Influenced by the fact that radio communication and sensing are considered to be the most energy consuming activities in such networks. Most of these approaches focused on either reducing the number of collected data using adaptive sampling techniques or on reducing the number of data transmitted over the network using prediction models. In this article, we propose a novel prediction-based data reduction method. furthermore, we combine it with an adaptive sampling rate technique, allowing us to significantly decrease energy consumption and extend the …
Optimization design process of a morphing winglet
2018
Aeronautic and aerospace engineering is recently moving in the direction of developing morphing wing devices, with the aim of making adaptable the aerodynamic shapes to different operational conditions. Those devices may be classified according to two different conceptual architectures: kinematic or compliant systems. Both of them embed within their body all the active components (actuators and sensors), necessary to their operations. In the first case, the geometry variation is achieved through an augmented classical mechanism, while in the second case the form modification is due to a special arrangement of the inner structure creating a distributed elastic hinges arrangement. Whatever is…
Three-dimensional analysis of tumour vascular corrosion casts using stereoimaging and micro-computed tomography
2009
Objective: In order to perform effective translational research for cancer therapy, we need to employ preclinical models which reflect the clinical situation. The purpose of this study was to quantitatively compare the vascular architecture of human colorectal cancer and experimental tumour models to determine the suitability of animal models for vascular studies and antivascular therapy.Methods: In this study we investigated the three-dimensional properties of colonic tumour vasculature in both human clinical tissues (normal mucosa control [n = 20], carcinoma [n = 20] and adenoma In = 61) and murine colorectal xenografts (LS147T [n = 6] and SW1222 [n = 6]). Scanning Electron Microscope Ste…
3D microvascular architecture of pre-cancerous lesions and invasive carcinomas of the colon.
2001
Despite the significance of tumour neoangiogenesis and the extensive knowledge on the molecular basis of blood vessel formation currently no quantitative data exist on the 3D microvascular architecture in human primary tumours and their precursor lesions. This prompted us to examine the 3D vascular network of normal colon mucosa, adenomas and invasive carcinomas by means of quantitative microvascular corrosion casting. Fresh hemicolectomy specimens from 20 patients undergoing cancer or polyposis coli surgery were used for corrosion casting, factor VIII and VEGF immunostaining. In addition, immunostaining was done on colorectal tissue from 33 patients with metastatic and non-metastatic carci…
Legibility of Text and Pictograms in Variable Message Signs: Can Single-Word Messages Outperform Pictograms?
2018
The current research shows the advantage of single-word messages in the particular case of variable message signs (VMSs) with a high aspect ratio.Early studies on traffic sign design proposed that pictorial information would advantage equivalent text messages in static signs.We used a driving simulator to present individually 36 VMSs, showing six words (e.g., "congestion") and six danger signs (e.g., congestion traffic sign). In Experiment 1, 18 drivers read aloud the text or orally identified the pictograms as soon as they could correctly do it. In Experiment 2, a different sample of 18 drivers gave a motor response, according to the meaning of the message. We analyzed the legibility dista…
Association between long-term exercise loading and lumbar spine trabecular bone score (TBS) in different exercise loading groups
2015
Objective: To examine whether different exercise loading is associated with lumbar vertebral texture as assessed with Trabecular Bone Score (TBS). Methods: Data from 88 Finnish female athletes and 19 habitually active women (reference group) were analyzed. Participants’mean age was 24.3 years(range 17-40 years).Athletes were divided into five specific exercise loading groups according to sport-specific training history: high-impact (triple jumpers and high jumpers), odd-impact (soccer players and squash players), high-magnitude (power lifters), repetitive impact (endurance runners), and repetitive non-impact (swimmers). TBS-values were determined from lumbar vertebral L1-L4 DXA images. Body…