Search results for "git"
showing 10 items of 7116 documents
Optimization of a Time-to-Digital Converter and a coincidence map algorithm for TOF-PET applications
2015
This contribution describes the optimization of a multichannel high resolution Time-to-Digital Converter (TDC) in a Field-Programmable Gate Array (FPGA) initially capable of obtaining time resolutions below 100ps for multiple channels. Due to its fast propagation capability it has taken advantage of the FPGA internal carry logic for accurate time measurements. Furthermore, the implementation of the TDC has been performed in different clock regions and tested with different frequencies as well, achieving improvements of up to 50% for a pair of channels. Moreover, since the TDC is potentially going to be used in a trigger system for Positron Emission Tomography (PET), the algorithm for coinci…
Trusted Computing and DRM
2015
Trusted Computing is a special branch of computer security. One branch of computer security involves protection of systems against external attacks. In that branch we include all methods that are used by system owners against external attackers, for example Firewalls, IDS, IPS etc. In all those cases the system owner installs software that uses its own means to determine if a remote user is malicious and terminates the attack. (Such means can be very simple such as detecting signatures of attacks or very complex such as machine learning and detecting anomalies in the usage pattern of the remote user). Another branch of attacks requires protection by the system owner against internal users. …
Taking Online Search Queries as an Indicator of the Public Agenda
2016
Recently, several studies suggested that the amount of online search queries can be used as an indicator of the public agenda. Based on former research by the authors, this article discusses the role of public uncertainty as another factor influencing search queries. Therefore, the influence of media coverage on Wikipedia searches concerning two issues is compared: one issue with uncertainty (the Enterohaemorrhagic Escherichia coli [EHEC] epidemic), and one without uncertainty (unemployment). Analyses show much stronger correlations in the case of EHEC, which suggests that online search behavior may especially be used as an indicator of the public agenda in case public uncertainty exists.
Digital selection of composite resin shade using cross polarized photography and a standardized white balance gray reference card
2021
Purpose The aim of the present case report was to describe, through a clinical case, a step-by-step technique, for the digital selection of composite resin shades using cross polarization and white balance employing a standardized reference card. Case Description After intraoral impression, a digital diagnostic wax up was developed. A 3D printed cast was used to fabricate a lingual polyvinyl siloxane matrix. First a cross-polarized image of the contralateral central incisor was taken in RAW format, using a gray reference card. The digital image was manipulated using this card as a reference, to obtain reliable color values. The obtained color values, from the contralateral central incisor, …
<title>Fast motion estimation based on spatio-temporal Gabor filters: parallel implementation on multi-DSP</title>
2000
The aim of our work is to implement a system of motion estimation in image sequences processing on DSP's: fast motion estimation based on Gabor spatio-temporal filters. Our approach consists to calculate optical flow using an energy-based method, named combined filtering which associates the energetic responses of Gabor spatio- temporal filters organized in triads. For this purpose, we applicate a technique developed by the Laboratory LIS in France, inspired from the architecture of Heeger. To reduce the computation time, we present also a parallel implementation of the algorithm on a multi-DSP architecture using SynDEx tool which is a programming environment to generate optimized distribut…
A reconfigurable architecture for autonomous visual-navigation
2003
This paper describes the design of a reconfigurable architecture for implementing image processing algorithms. This architecture is a pipeline of small identical processing elements that contain a programmable logic device (FPGA) and double port memories. This processing system has been adapted to accelerate the computation of differential algorithms. The log-polar vision selectively reduces the amount of data to be processed and simplifies several vision algorithms, making possible their implementation using few hard-ware resources. The reconfigurable architecture design has been devoted to implementation, and has been employed in an autonomous platform, which has power consumption, size a…
Repair Mechanisms for Broadcast Transmissions in Hybrid Cellular &#x00026; DVB-H Systems
2006
This paper proposes a framework for investigating potential infrastructure cost savings in hybrid cellular and DVB- H systems by performing efficient error repair of broadcast transmissions. The main idea is to reuse as much as possible the existing network infrastructure to provide mobile TV services. The cellular system is not only employed to collect information, but also to send repair data to the users whose conditions are temporarily affected by noise, interference and fading. To enable an easy and efficient implementation of the repair mechanisms we adopt the use of application layer - forward error correction (AL-FEC) with digital fountain coding.
Application Layer FEC for Mobile TV Delivery in IP Datacast Over DVB-H Systems
2009
In this paper we investigate the potential gain that can be obtained in DVB-H using application layer forward error correction (AL-FEC) to perform a multi-burst protection of the transmission for improving the reception of streaming services for mobile terminals. Compared to the conventional approach with link layer multi protocol encapsulation FEC (MPE-FEC), this technique allows to increase the robustness of the DVB-H transmission not only as a function of the capacity devoted for error repair (FEC overhead), but also as a function of the number of bursts jointly encoded. The main drawback of this approach is an increase of the network latency, that can be translated into a larger service…
Impact of Storage Acquisition Intervals on the Cost-Efficiency of the Private vs. Public Storage
2012
The volume of worldwide digital content has increased nine-fold within the last five years, and this immense growth is predicted to continue in foreseeable future reaching 8ZB already by 2015. Traditionally, in order to cope with the growing demand for storage capacity, organizations proactively built and managed their private storage facilities. Recently, with the proliferation of public cloud infrastructure offerings, many organizations, instead, welcomed the alternative of outsourcing their storage needs to the providers of public cloud storage services. The comparative cost-efficiency of these two alternatives depends on a number of factors, among which are e.g. the prices of the public…
Features extraction on complex images
2005
The accessibility of inexpensive and powerful computers has allowed true digital holography to be used for industrial inspection using microscopy. This technique allows the capture of a complex image (i.e., one containing magnitude and phase), and the reconstruction of the phase and magnitude information. Digital holograms give a new dimension to texture analysis, since the topology information can be used as an additional way to extract features. This new technique can be used to extend previous work on the image segmentation of patterned wafers for defect detection. The paper presents a comparison between the features obtained using Gabor filtering on complex images under illumination and…