Search results for " processing"

The "Livio Scarsi" X-Ray Facility at University of Palermo for Device Testing

2015

In this work, we report on the characteristics of the Livio Scarsi X-ray facility at University of Palermo. The facility is able to produce low energy X rays, within the energy range of 0.1-60 keV, with fluence rates ranging from 105-108 photons/mm2 s. The laboratory is equipped with an innovative digital detection system, based on semiconductor detectors (Si and CdTe detectors), able to provide accurate and precise estimation of the fluence rate, the energy and the exposure of X rays, even at high counting rate conditions. Instrumentation for electrical characterization (DC-AC) of semiconductor devices, for both off-line and on-line (i.e. during the irradiation) measurements, is also avail…

2014

A 3D imaging technique using a high speed binocular stereovision system was developed in combination with corresponding image processing algorithms for accurate determination of the parameters of particles leaving the spinning disks of centrifugal fertilizer spreaders. Validation of the stereo-matching algorithm using a virtual 3D stereovision simulator indicated an error of less than 2 pixels for 90% of the particles. The setup was validated using the cylindrical spread pattern of an experimental spreader. A 2D correlation coefficient of 90% and a Relative Error of 27% was found between the experimental results and the (simulated) spread pattern obtained with the developed setup. In combin…

Digital techniques for high-rate high-resolution radiation measurements

2014

Digital pulse processing (DPP) techniques are increasingly used in the development of modern spectroscopic systems. DPP systems, based on direct digitizing and processing of detector signals (preamplifier output signals), ensure higher flexibility, stability, lower dead time, higher throughput and better energy resolution than traditional pulse processing systems. In this work, we present our progress in the development of DPP systems for high-rate high-resolution radiation measurements. An innovative digital system, able to perform multi-parameter analysis (input counting rate, pulse height, pulse shape, event arrival time, etc.) even at high photon counting rates is presented. Experimenta…

Three dimensional reconstruction of intracoronary ultrasound images: roadmapping with simultaneously digitised coronary angiograms

2002

Three dimensional reconstruction of intracoronary ultrasound images offers a better appreciation of the axial relationship of vessel features and permits volumetric assessment, both of which depend critically on the spatial accuracy of the technique. This in turn is dependent on precise longitudinal orientation of the transducer in the vessel. The authors have developed a system which utilises simultaneously digitised fluoroscopic tracking of the radio-opaque transducer to orient the corresponding 2D ICUS images. This system may offer improved spatial accuracy of the three dimensional reconstruction and a means of precise identification of the 2D ICUS image which corresponds with a selected…

Memetic Differential Evolution Frameworks in Filter Design for Defect Detection in Paper Production

2009

This chapter studies and analyzes Memetic Differential Evolution (MDE) Frameworks for designing digital filters, which aim at detecting paper defects produced during an industrial process. MDE Frameworks employ the Differential Evolution (DE) as an evolutionary framework and a list of local searchers adaptively coordinated by a control scheme. Here, three different variants of MDE are taken into account and their features and performance are compared. The binomial explorative features of the DE framework in contraposition to the exploitative features of the local searcher are analyzed in detail in light of the stagnation prevention problem, typical for the DE. Much emphasis in this chapter …

Kalman filtering applied to Profibus-DP systems. Multirate control systems with delayed signals

2008

In networked control systems several devices (controllers, sensors and actuators) share a common communication resource. This feature can introduce variable and even random delays when those devices try to transmit information through the shared medium. The limited bandwidth capabilities of the transmission medium also can restrict the freedom to set the sampling periods in the control loop. An attempt to reduce the significance of the signal delays and save to some bandwidth can be based on high values of sampling periods. Usually this solution has remarkable effects in the system performance because with higher sampling periods closed loop response capabilities are decreased. This paper p…

Multimedia applications in industrial networks: integration of image processing in profibus

2003

This paper analyzes the transmission of images through Profibus for applications concerned with the processing of images integrated in control systems, by means of a detailed study of two real cases with different bandwidth requirements. We analyze the special features of an artificial vision system making use of Profibus as a transport system, the scheduling of the traffic in order to guarantee the delivery of the images and the control traffic before their deadlines, the protocol used, and the compression techniques usable in this kind of system, which enable us to reduce the necessary bandwidth for the applications without degrading the operation of the image processing application. We p…

Optimizing the MAC Protocol in Localization Systems Based on IEEE 802.15.4 Networks

2017

Radio frequency signals are commonly used in the development of indoor localization systems. The infrastructure of these systems includes some beacons placed at known positions that exchange radio packets with users to be located. When the system is implemented using wireless sensor networks, the wireless transceivers integrated in the network motes are usually based on the IEEE 802.15.4 standard. But, the CSMA-CA, which is the basis for the medium access protocols in this category of communication systems, is not suitable when several users want to exchange bursts of radio packets with the same beacon to acquire the radio signal strength indicator (RSSI) values needed in the location proce…

Power Consumption Analysis of Operating Systems for Wireless Sensor Networks

2010

In this paper four wireless sensor network operating systems are compared in terms of power consumption. The analysis takes into account the most common operating systems-TinyOS v1.0, TinyOS v2.0, Mantis and Contiki-running on Tmote Sky and MICAz devices. With the objective of ensuring a fair evaluation, a benchmark composed of four applications has been developed, covering the most typical tasks that a Wireless Sensor Network performs. The results show the instant and average current consumption of the devices during the execution of these applications. The experimental measurements provide a good insight into the power mode in which the device components are running at every moment, and t…

Life cycle assessment of a solar thermal collector: sensitivity analysis, energy and environmental balances

2005

Abstract Starting from the results of a life cycle assessment of solar thermal collector for sanitary warm water, an energy balance between the employed energy during the collector life cycle and the energy saved thanks to the collector use has been investigated. A sensitivity analysis for estimating the effects of the chosen methods and data on the outcome of the study was carried out. Uncertainties due to the eco-profile of input materials and the initial assumptions have been analysed. Since the study is concerned with a renewable energy system, attention has been focused on the energy indexes and in particular the “global energy consumption”. Following the principles of Kyoto Protocol, …