1,424 research outputs found
Timing Signals and Radio Frequency Distribution Using Ethernet Networks for High Energy Physics Applications
Timing networks are used around the world in various applications from telecommunications systems to industrial processes, and from radio astronomy to high energy physics. Most timing networks are implemented using proprietary technologies at high operation and maintenance costs. This thesis presents a novel timing network capable of distributed timing with subnanosecond accuracy. The network, developed at CERN and codenamed âWhite- Rabbitâ, uses a non-dedicated Ethernet link to distribute timing and data packets without infringing the sub-nanosecond timing accuracy required for high energy physics applications. The first part of this thesis proposes a new digital circuit capable of measuring time differences between two digital clock signals with sub-picosecond time resolution. The proposed digital circuit measures and compensates for the phase variations between the transmitted and received network clocks required to achieve the sub-nanosecond timing accuracy. Circuit design, implementation and performance verification are reported. The second part of this thesis investigates and proposes a new method to distribute radio frequency (RF) signals over Ethernet networks. The main goal of existing distributed RF schemes, such as Radio-Over-Fibre or Digitised Radio-Over-Fibre, is to increase the bandwidth capacity taking advantage of the higher performance of digital optical links. These schemes tend to employ dedicated and costly technologies, deemed unnecessary for applications with lower bandwidth requirements. This work proposes the distribution of RF signals over the âWhite-Rabbitâ network, to convey phase and frequency information from a reference base node to a large numbers of remote nodes, thus achieving high performance and cost reduction of the timing network. Hence, this thesis reports the design and implementation of a new distributed RF system architecture; analysed and tested using a purpose-built simulation environment, with results used to optimise a new bespoke FPGA implementation. The performance is evaluated through phase-noise spectra, the Allan-Variance, and signalto- noise ratio measurements of the distributed signals
A connection method for a defeasible extension of
This paper proposes a connection method \`a la Bibel for an
exception-tolerant family of description logics (DLs). As for the language, we
assume the DL extended with two typicality operators: one on
(complex) concepts and one on role names. The language is a variant of
defeasible DLs, as broadly studied in the literature over the past decade, in
which most of these can be embedded. We revisit the definition of the matrix
representation of a knowledge base and establish the conditions for a given
axiom to be provable. We show that the calculus terminates and is sound and
complete w.r.t. a DL version of the preferential semantics widely adopted in
non-monotonic reasoning
Recommended from our members
The gathering firestorm in southern Amazonia.
Wildfires, exacerbated by extreme weather events and land use, threaten to change the Amazon from a net carbon sink to a net carbon source. Here, we develop and apply a coupled ecosystem-fire model to quantify how greenhouse gas-driven drying and warming would affect wildfires and associated CO2 emissions in the southern Brazilian Amazon. Regional climate projections suggest that Amazon fire regimes will intensify under both low- and high-emission scenarios. Our results indicate that projected climatic changes will double the area burned by wildfires, affecting up to 16% of the region's forests by 2050. Although these fires could emit as much as 17.0 Pg of CO2 equivalent to the atmosphere, avoiding new deforestation could cut total net fire emissions in half and help prevent fires from escaping into protected areas and indigenous lands. Aggressive efforts to eliminate ignition sources and suppress wildfires will be critical to conserve southern Amazon forests
A Case Report of a Sclerotic Fibroma of the Oral Mucosa
Sclerotic fibroma, also known as storiform collagenoma, is a rare benign tumor that grows on the skin, but it can also appear, less frequently, in the oral mucosa. It can present as part of Cowden syndrome manifestation, especially when multiple lesions are encountered, but it may also appear as a solitary, sporadic lesion in healthy individuals. We describe a patient, diagnosed with Cowden syndrome, who presented with a sclerotic fibroma in the oral mucosa, which is a very uncommon manifestation of Cowden syndrome.info:eu-repo/semantics/publishedVersio
Dermatological remedies in the traditional pharmacopoeia of Vulture-Alto Bradano, inland southern Italy
Dermatological remedies make up at least one-third of the traditional pharmacopoeia in southern Italy. The identification of folk remedies for the skin is important both for the preservation of traditional medical knowledge and in the search for novel antimicrobial agents in the treatment of skin and soft tissue infection (SSTI). Our goal is to document traditional remedies from botanical, animal, mineral and industrial sources for the topical treatment of skin ailments. In addition to SSTI remedies for humans, we also discuss certain ethnoveterinary applications.
Field research was conducted in ten communities in the Vulture-Alto Bradano area of the Basilicata province, southern Italy. We randomly sampled 112 interviewees, stratified by age and gender. After obtaining prior informed consent, we collected data through semi-structured interviews, participant-observation, and small focus groups techniques. Voucher specimens of all cited botanic species were deposited at FTG and HLUC herbaria located in the US and Italy.
We report the preparation and topical application of 116 remedies derived from 38 plant species. Remedies are used to treat laceration, burn wound, wart, inflammation, rash, dental abscess, furuncle, dermatitis, and other conditions. The pharmacopoeia also includes 49 animal remedies derived from sources such as pigs, slugs, and humans. Ethnoveterinary medicine, which incorporates both animal and plant derived remedies, is addressed. We also examine the recent decline in knowledge regarding the dermatological pharmacopoeia.
The traditional dermatological pharmacopoeia of Vulture-Alto Bradano is based on a dynamic folk medical construct of natural and spiritual illness and healing. Remedies are used to treat more than 45 skin and soft tissue conditions of both humans and animals. Of the total 165 remedies reported, 110 have never before been published in the mainland southern Italian ethnomedical literature
In vitro and in vivo characterization of PLLA-316L stainless steel electromechanical devices for bone tissue engineeringâA preliminary study
Bone injuries represent a major social and financial impairment, commonly requiring surgical intervention due to a limited healing capacity of the tissue, particularly regarding critical-sized defects and non-union fractures. Regenerative medicine with the application of bone implants has been developing in the past decades towards the manufacturing of appropriate devices. This work intended to evaluate medical 316L stainless steel (SS)-based devices covered by a polymer poly (L-lactic acid) (PLLA) coating for bone lesion mechanical and functional support. SS316L devices were subjected to a previously described silanization process, following a three-layer PLLA film coating. Devices were further characterized and evaluated towards their cytocompatibility and osteogenic potential using human dental pulp stem cells, and biocompatibility via subcutaneous implantation in a rat animal model. Results demonstrated PLLA-SS316L devices to present superior in vitro and in vivo outcomes and suggested the PLLA coating to provide osteo-inductive properties to the device. Overall, this work represents a preliminary study on PLLA-SS316L devicesâ potential towards bone tissue regenerative techniques, showing promising outcomes for bone lesion support.This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, FCT Ref. UID/CTM/50011/2019, financed by national funds through the FCT/MCTES and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. This work was also financed by Portugal 2020 through the European Regional Development Fund (ERDF), in the frame of Operational Competitiveness and Internationalization Programme (POCI), in the scope of the project âAdvanced BioMEMs for tissue engineering: Applications in hard tissue (BioMEMs)â, POCI-01-0145-FEDER-032095. Mariana Vieira Branquinho (SFRH/BD/146172/2019), Ana Catarina Sousa (SFRH/BD/146689/2019), and Rui DamĂĄsio Alvites (SFRH/BD/116118/2016), acknowledge FCT, for financial support
- âŠ