Abstract

Obstructive sleep apnea syndrome (OSAS) consists in the occurrence of recurrent episodes of airflow limitation during sleep, with undesirable consequences for the health. The phenomenon is well known from a medical point of view (prognosis, diagnosis and treatment), but there is not a methodology or analysis tools for the quantification of the clinical response using Mandibular Advancement Devices (MAD). This paper shows how combining image processing, fluid dynamics and engineering design criteria, imported from other fields, allow to establish a simple analysis method clinically useful to decide the more convenient positioning of the MAD based on the pressure or mechanical movement of the jaw. This methodology is applied to a patient suffering OSAS which the objective to evaluate the changes provoked in the upper-airways due to an innovative mandibular device.

Abstract

This paper addresses web analytics from an images perspective, using big data technologies. Images are increasingly present on the web, and therefore any web analysis must consider them. The huge volume of available images requires the use of large computation infrastructures in order to generate this kind of analysis, as well as specific computer vision algorithms. Big data technologies are discussed that can be used for large-scale image processing. In addition, a novel distributed algorithm is proposed that can efficiently retrieve images from an online collection at low computational cost. This algorithm can be used in web analysis or future research requiring detailed image study, without requiring any special hardware.

Abstract

This study's focus is on modeling vehicle acceleration-deceleration behavior during freeway and ramp maneuvers in congested traffic. Presented are methodologies for collecting field data, analyzing freeway merging behavior data and developing and calibrating ramp vehicle accelerating models. Substantial data were collected using videotape and image processing techniques. The entrance ramps in the Tokyo Metropolitan Expressway were used for comprehensive traffic surveys. The paper presents a theoretical framework for modeling the ramp driver acceleration-deceleration behavior. The methodology uses the stimuli-response psychophysical concept as a fundamental rule and is formulated as a modified form of the car-following models. The findings could serve future highway geometric design criteria revision, and the mathematical framework of the developed model may be appropriate to study more driver behavioral aspects of congested freeways. Document type: Part of book or chapter of book

Abstract

This paper describes a system for pedestrian detection in infrared images implemented and tested on an experimental vehicle. A specific stabilization procedure is applied after image acquisition and before processing to cope with vehicle movements affecting the camera calibration. The localization of pedestrians is based on the search for warm symmetrical objects with specific size and aspect ratio. A set of filters is used to reduce false detections. The final validation process relies on the human shape’s morphological characteristics. Document type: Part of book or chapter of book

Abstract

The thermal infrared imager TIR onboard Hayabusa2 has been developed to investigate thermo-physical properties of C-type, near-Earth asteroid 162173 Ryugu. TIR is one of the remote science instruments on Hayabusa2 designed to understand the nature of a volatile-rich solar system small body, but it also has significant mission objectives to provide information on surface physical properties and conditions for sampling site selection as well as the assessment of safe landing operations. TIR is based on a two-dimensional uncooled micro-bolometer array inherited from the Longwave Infrared Camera LIR on Akatsuki (Fukuhara et al., 2011). TIR takes images of thermal infrared emission in 8 to 12 ?m with a field of view of \\(16 \\times 12^{\\circ}\\) and a spatial resolution of \\(0.05^{\\circ}\\) per pixel. TIR covers the temperature range from 150 to 460 K, including the well calibrated range from 230 to 420 K. Temperature accuracy is within 2 K or better for summed images, and the relative accuracy or noise equivalent temperature difference (NETD) at each of pixels is 0.4 K or lower for the well-calibrated temperature range. TIR takes a couple of images with shutter open and closed, the corresponding dark frame, and provides a true thermal image by dark frame subtraction. Data processing involves summation of multiple images, image processing including the StarPixel compression (Hihara et al., 2014), and transfer to the data recorder in the spacecraft digital electronics (DE). We report the scientific and mission objectives of TIR, the requirements and constraints for the instrument specifications, the designed instrumentation and the pre-flight and in-flight performances of TIR, as well as its observation plan during the Hayabusa2 mission. Document type: Part of book or chapter of book

Abstract

Proceeding of: Second Iberian Conference, IbPRIA 2005, Estoril, Portugal, June 7-9, 2005 Computer Vision can provide a great deal of assistance to Intelligent Vehicles. In this paper an Advanced Driver Assistance Systems for Vehicle Detection is presented. A geometric model of the vehicle is defined where its energy function includes information of the shape and symmetry of the vehicle and the shadow it produces. A genetic algorithm finds the optimum parameter values. As the algorithm receives information from a road detection module some geometric restrictions can be applied. A multi-resolution approach is used to speed up the algorithm and work in realtime. Examples of real images are shown to validate the algorithm. Publicado Document type: Part of book or chapter of book

Abstract

En este documento se describe una sistema de adquisición de variables de tráfico vehicular usando técnicas de visión por computador mediante una cámara ubicada en una vía de máximo tres carriles, se describen los procedimientos a seguir en la ubicación de la cámara y las configuraciones propias del algoritmo para que se presente una efectividad en la estimación superior al 95%. This document describes an acquisition system for vehicular traffic variables using computer vision techniques using a camera on a maximum three-lane road, describes the procedures to be followed in the location of the camera and settings specific to the algorithm that estimate effectiveness in the estimation of traffic variables greater than 95%.

Abstract

Image Processing (IP) applications have become popular with the advent of efficient algorithms and low-cost CMOS cameras with high resolution. However, IP applications are compute-intensive, consume a lot of energy and have long processing times. Image approximation has been proposed by recent works for an energy-efficient design of these applications. It also reduces the impact of long processing times. The challenge here is that the IP applications often work as a part of bigger closed-loop control systems, e.g. advanced driver assistance system (ADAS). The impact of image approximations that tolerate certain error on these image-based control (IBC) systems is very important. However, there is a lack of tool support to evaluate the performance of such closed-loop IBC systems when the IP is approximated. We propose a framework - for both software-in-the-loop (SiL) and hardware-in-the-loop (HiL) simulation - for performance evaluation of image approximation on a closed-loop automotive IBC system (IMACS). Both simulation setups model the 3D environment in 3ds Max, and simulate the system dynamics, camera position and environment in V-REP. Our SiL setup simulates the system software in C++ or Matlab. Here, V-REP runs as a server and the software as a client in synchronous mode. Our HiL simulation setup runs the system software in the NVIDIA Drive PX2 platform and communicates to V-REP using application programming interfaces (APIs) for synchronous execution. We show the effectiveness of our framework using a vision-based lateral control example.

Abstract

The purpose of this paper is to present a method to model earthing systems subjected to lightning strikes with a one-dimensional moment method. This paper was conducted because an accurate method to model earthing systems subjected to lightning strikes, was deemed necessary. To name a few examples of relevant situations: supply stations of railway systems, from which also critical signalling infrastructure is fed, earthing systems of cellular phone basestations, located in the vicinity of high-antenna towers, prone to lightning strikes, and gas and oil pipelines. There exist already methods to solve this problem, based on circuit theory, but the electromagnetic method of this work is based directly on Maxwell’s equations and therefore more accurate. The earthing electrodes and meshes are represented as wire scatterers. First, the method is outlined for scatterers in a single medium. Next, the method is extended to model to presence of the soil-air interface layer. An approximate technique, known as the modified image theory, is used to account for the vicinity of the soil. Finally, a second extension is given so that cables without metal sheets which are in the vicinity of the earthing systems, can be included in the model. Thereafter, it is described how the method can be used to calculate the effects of lightning strikes on earthing structures, and finally a validation of the method is presented. The method is validated by applying it to simple situations which can also analytically be calculated, and by applying it to earthing structures for which the transient voltage was measured or calculated with circuit methods. A good agreement is seen. However, the method is computationally very expensive. ispartof: COMPEL vol:28 issue:4 pages:989-1004 ispartof: location:Graz, AUSTRIA status: published