301 research outputs found
A Narrow Optical Pulse Emitter Based on LED: NOPELED
Light sources emitting short pulses are needed in many particle physics experiments using
optical sensors as they can replicate the light produced by the particles being detected and are also an
important calibration and test element. This work presents NOPELED, a light source based on LEDs
emitting short optical pulses with typical rise times of less than 3 ns and FullWidth at Half Maximum
lower than 7 ns. The emission wavelength depends on the model of LED used. Several LED models
have been characterized in the range from 405 to 532 nm, although NOPELED can work with LED
emitting wavelengths outside of that region. While the wavelength is fixed for a given LED model,
the intensity and the frequency of the optical pulse can be controlled. NOPELED, which also has
low cost and simple operation, can be operated remotely, making it appropriate for either different
physics experiments needing in-place light sources such as astrophysical neutrino detectors using
photo-multipliers or positron emission tomography devices using scintillation counters, or, beyond
physics, applications needing short pulses of light such as protein fluorescence or chemodetection of
heavy metals.Spanish Ministerio de Ciencia, Innovacion, Investigacion y Universidades (MCIU) PGC2018-096663-B-C41
PGC2018-096663-A-C42
PGC2018-096663-B-C43
PGC2018-096663-B-C44Center for Forestry Research & Experimentation (CIEF) PROMETEO/2020/019Generalitat Valenciana: Grisolia GRISOLIA/2018/119
Generalitat Valenciana: GenT CIDEGENT/2018/034
CIDEGENT/2020/04
Precise Network Time Monitoring: Picosecond-level packet timestamping for Fintech networks
Network visibility and monitoring are critical in modern networks due to the increased density, additional complexity, higher bandwidth, and lower latency requirements. Precise packet timestamping and synchronization are essential to temporally correlate captured information in different datacenter locations. This is key for visibility, event ordering and latency measurements in segments as telecom, power grids and electronic trading in finance, where order execution and reduced latency are critical for successful business outcomes. This contribution presents Precise Network Time Monitoring (PNTM), a novel mechanism for asynchronous Ethernet packet timestamping which adapts a Digital Dual Mixer Time Difference (DDMTD) implemented in an FPGA. Picosecond-precision packet timestamping is outlined for 1 Gigabit Ethernet. Furthermore, this approach is combined with the White Rabbit (WR) synchronization protocol, used as reference for the IEEE 1588-2019 High Accuracy Profile to provide unprecedented packet capturing correlation accuracy in distributed network scenarios thanks to its sub-nanosecond time transfer. The paper presents different application examples, describes the method of implementation, integration of WR with PNTM and subsequently describes experiments to demonstrate that PNTM is a suitable picosecond-level distributed packet timestamping solutionNational project AMIGA7
RTI2018-096228-B-C32Andalusian project SINPA
B-TIC-445-UGR1
Ethernet-based timing system for accelerator facilities: The IFMIF-DONES case
This article presents the design of a timing system for accelerator facilities, which relies on a general networking
approach based on standard Ethernet protocols that keeps all the devices synchronized to a common time
reference. The case of the IFMIF-DONES infrastructure is studied in detail, providing a framework for the
implementation of the timing system. The network time protocol (NTP) with software timestamping and the
precision time protocol (PTP) with hardware timestamping are used to synchronize devices with sub-millisecond
and sub-microsecond accuracy requirements, respectively. The design also considers the utilization of IEEE 1588
high accuracy default PTP profile (PTP-HA) to provide sub-nanosecond accuracy for the most demanding
components. Three different solutions for the design of the timing system are discussed in detail. The first solution
considers the deployment of one time-dedicated network for each synchronization protocol, while the
second one proposes the integration of the synchronization data of NTP and PTP into the networks of the facility.
The third solution relies on the single distribution of PTP-HA to all the systems. The final design aims to be fully
based on standard technologies and to be cost-efficient, seeking for interoperability and scalability, and minimizing
the impact on other systems in the facility. An experimental setup has been implemented to evaluate and
discuss the suitability of the solutions for the timing system by studying the synchronization accuracy obtained
with NTP, PTP and PTP-HA under different network conditions. It includes a timing evaluation platform that
tries to resemble the network architecture foreseen in the facility. The measured results revealed that PTP is the
most limiting protocol for the second solution. Using the default PTP configuration, it tolerates less than 20% of
maximum bandwidth utilization for symmetric bidirectional flows, and around 30% in the case of unidirectional
flows (server to client or client to server), with the current setup and using switches without enabled timing
support. This case study provides a better understanding of the trade-off between bandwidth utilization, synchronization
accuracy and cost in these kinds of facilities
Time-sensitive networking for interlock propagation in the IFMIF-DONES facility
In this study, we have proposed the use of time-sensitive networking (TSN) technologies for the distribution of
the interlock signals of the machine protection system of the future IFMIF-DONES particle accelerator, required
for implementing the protection mechanisms of the different systems in the facility. Such facilities usually rely on
different fieldbus technologies or direct wiring for their transmission, typically leading to complex network
infrastructures and interoperability problems. We provide insights of how TSN could simplify the deployment of
the interlock network by aggregating all the traffic under the same network infrastructure, whilst guaranteeing
the latency and timing constraints. Since TSN is built on top of Ethernet technology, it also benefits from other
network services and all its related developments, including redundancy and bandwidth improvements. The
main challenge to address is the transmission of the interlock signals with very low latency between devices
located in different points of the facility. We have characterized our initial TSN architecture prototype, evaluated
the latency and bandwidth obtained with this solution, identified applications to effectively shape the attainable
determinism, and found shortcomings and areas of future improvements.Amiga-7 Grant
RTI2018-096228-B-C32Programa Operativo FEDER/Junta de Andalucia SINPA Grant
SINPA B-TIC-445-UGR18EU DAIS Project
101007273-2Spanish Government
FPU20/01857,
FPU20/05842Misiones CDTI 2021 framework (DONES-EVO)
MIG-20211006European Union via the Euratom Research and Training Programme
10105220
Predictive Control Applied to a Solar Desalination Plant Connected to a Greenhouse with Daily Variation of Irrigation Water Demand
The water deficit in the Mediterranean area is a known matter severely affecting agriculture. One way to avoid the aquifersâ exploitation is to supply water to crops by using thermal desalination processes. Moreover, in order to guarantee long-term sustainability, the required thermal energy for the desalination process can be provided by solar energy. This paper shows simulations for a case study in which a solar multi-effect distillation plant produces water for irrigation purposes. Detailed models of the involved systems are the base of a predictive controller to operate the desalination plant and fulfil the water demanded by the crops
On the Detection Capabilities of Signature-Based Intrusion Detection Systems in the Context of Web Attacks
Signature-based Intrusion Detection Systems (SIDS) play a crucial role within the arsenal of security components of most organizations. They can find traces of known attacks in the network traffic or host events for which patterns or signatures have been pre-established. SIDS include standard packages of detection rulesets, but only those rules suited to the operational environment should be activated for optimal performance. However, some organizations might skip this tuning process and instead activate default off-the-shelf rulesets without understanding its implications and trade-offs. In this work, we help gain insight into the consequences of using predefined rulesets in the performance of SIDS. We experimentally explore the performance of three SIDS in the context of web attacks. In particular, we gauge the detection rate obtained with predefined subsets of rules for Snort, ModSecurity and Nemesida using seven attack datasets. We also determine the precision and rate of alert generated by each detector in a real-life case using a large trace from a public webserver. Results show that the maximum detection rate achieved by the SIDS under test is insufficient to protect systems effectively and is lower than expected for known attacks. Our results also indicate that the choice of predefined settings activated on each detector strongly influences its detection capability and false alarm rate. Snort and ModSecurity scored either a very poor detection rate (activating the less-sensitive predefined ruleset) or a very poor precision (activating the full ruleset). We also found that using various SIDS for a cooperative decision can improve the precision or the detection rate, but not both. Consequently, it is necessary to reflect upon the role of these open-source SIDS with default configurations as core elements for protection in the context of web attacks. Finally, we provide an efficient method for systematically determining which rules deactivate from a ruleset to significantly reduce the false alarm rate for a target operational environment. We tested our approach using Snortâs ruleset in our real-life trace, increasing the precision from 0.015 to 1 in less than 16 h of work. View Full-TextMinisterio de Ciencias e InnovaciĂłn (MICINN)/AEI 10.13039/501100011033: PID2020-115199RB-I00FEDER/Junta de AndalucĂa-ConsejerĂa de TransformaciĂłn EconĂłmica, Industria, Conocimiento y Universidades PYC20-RE-087-US
The Biology of Pichia membranifaciens Killer Toxins
The killer phenomenon is defined as the ability of some yeast to secrete toxins that are lethal to other sensitive yeasts and filamentous fungi. Since the discovery of strains of Saccharomyces cerevisiae capable of secreting killer toxins, much information has been gained regarding killer toxins and this fact has substantially contributed knowledge on fundamental aspects of cell biology and yeast genetics. The killer phenomenon has been studied in Pichia membranifaciens for several years, during which two toxins have been described. PMKT and PMKT2 are proteins of low molecular mass that bind to primary receptors located in the cell wall structure of sensitive yeast cells, linear (1â6)-ÎČ-D-glucans and mannoproteins for PMKT and PMKT2, respectively. Cwp2p also acts as a secondary receptor for PMKT. Killing of sensitive cells by PMKT is characterized by ionic movements across plasma membrane and an acidification of the intracellular pH triggering an activation of the High Osmolarity Glycerol (HOG) pathway. On the contrary, our investigations showed a mechanism of killing in which cells are arrested at an early S-phase by high concentrations of PMKT2. However, we concluded that induced mortality at low PMKT2 doses and also PMKT is indeed of an apoptotic nature. Killer yeasts and their toxins have found potential applications in several fields: in food and beverage production, as biocontrol agents, in yeast bio-typing, and as novel antimycotic agents. Accordingly, several applications have been found for P. membranifaciens killer toxins, ranging from pre- and post-harvest biocontrol of plant pathogens to applications during wine fermentation and ageing (inhibition of Botrytis cinerea, Brettanomyces bruxellensis, etc.)
CDIO Experiences in Biomedical Engineering: Preparing Spanish Students for the Future of Medicine and Medical Device Technology
Biomedical engineering is one of the more recent fields of engineering, aimed at the application of engineering principles, methods and design concepts to medicine and biology for healthcare purposes, mainly as a support for preventive, diagnostic or therapeutic tasks. Biomedical engineering professionals are expected to achieve, during their studies and professional practice, considerable knowledge of both health sciences and engineering. Studying biomedical engineering programmes, or combining pre-graduate studies in life sciences with graduate studies in engineering, or vice versa, are typical options for becoming qualified biomedical engineering professionals, although there are additional interesting alternatives, to be discussed.
According to our experience, the graduates and post-graduates from multidisciplinary engineering programmes, not just from biomedical engineering, but also from more traditional fields including industrial, mechanical and telecommunications engineering, can play varied and very relevant roles in the biomedical industry and in extremely complex biomedical device development projects. In spite of the different ways of becoming a professional of the biomedical engineering field, it is true that their impact as successful professionals can be importantly increased, by means of an adequate integration into their curricula of fundamental biomedical engineering design concepts, methodologies and good practices, applied to the development of biomedical devices.
In this study we present the complete development and comparative study of three courses, belonging to different plans of study taught at the Technical University of Madrid and benefiting from using a CDIO approach focused on the development of biomedical devices. The three courses are âDevelopment of Medical Devicesâ, âBioengineering Designâ and âBiomedical Engineeringâ, respectively belonging to the
âBachelorâs Degree in Biomedical Engineeringâ, to the âMasterâs Degree in Industrial Engineeringâ and to the âMasterâs Degree in Mechanical Engineeringâ. During the courses, groups of students live through the development process of different biomedical devices aimed at providing answers to relevant social needs. Depending on their background and European credits assigned to the different courses, students carry out more conceptual projects or are able to live through more complete CDIO experiences. Main benefits, lessons learned and future challenges, linked to these courses, are analyzed, taking account of the results from 2014-2015 academic year
IEEE 1588 High Accuracy Default Profile: Applications and Challenges
Highly accurate synchronization has become a major requirement because of the rise of
distributed applications, regulatory requests and position, navigation and timing backup needs. This fact
has led to the development of new technologies which fulfill the new requirements in terms of accuracy
and dependability. Nevertheless, some of these novel proposals have lacked determinism, robustness,
interoperability, deployability, scalability or management tools preventing them to be extensively used in real
industrial scenarios. Different segments require accurate timing information over a large number of nodes.
Due to the high availability and low price of global satellite-based time references, many critical distributed
facilities depend on them. However, the vulnerability to jamming or spoofing represents a well-known
threat and back-up systems need to be deployed to mitigate it. The recently approved draft standard IEEE
1588-2019 includes the High Accuracy Default Precision Time Protocol Profile which is intensively based on
the White Rabbit protocol. White Rabbit is an extension of current IEEE 1588-2008 network synchronization
protocol for sub-nanosecond synchronization. This approach has been validated and intensively used
during the last years. This paper revises the pre-standard protocol to expose the challenges that the High
Accuracy profile will find after its release and covers existing applications, promising deployments and
the technological roadmap, providing hints and an overview of features to be studied. The authors review
different issues that have prevented the industrial adoption of White Rabbit in the past and introduce the
latest developments that will facilitate the next IEEE 1588 High Accuracy extensive adoption.This work was supported in part by the AMIGA6 under Grant AYA2015-65973-C3-2-R, in part by the AMIGA7 under Grant
RTI2018-096228-B-C32, and in part by the Torres Quevedo under Grant PTQ2018-010198
Optimized framegrabber for the Cherenkov telescope array
Our contribution presents a high bandwidth platform that implements traffic aggregation and switching
capabilities for the Cherenkov telescope array (CTA) cameras. Our proposed system integrates two different
data flows: a unidirectional one from the cameras to an external server and a second one, fully configurable
dedicated to configuration and control traffic for the camera management. The former requires high bandwidth
mechanisms to be able to aggregate several 1 gigabit Ethernet links into one high speed 10 gigabit Ethernet port.
The latter is responsible for providing routing components to allow a control and management path for all the
elements of the cameras. Hence, a simple, efficient, and flexible routing mechanism has been implemented
avoiding complex circuitry that impacts in the system performance. As a consequence, an asymmetric network
topology allows high bandwidth communication and, at the same time, a flexible and cost-effective implementation.
In our contribution, we analyze the camera requirements and present the proposed architecture.
Moreover, we have designed several evaluation tests to demonstrate that our solution fulfills the CTA project
needs. Finally, we illustrate the general possibilities of the proposed solution for other data acquisition applications
and the most promising futures lines of research are discussed.This work
has been partially funded by the Horizon 2020 (H2020)
ASTERICS (Grant No. 653477) and AYA2015-65973-C3-2-R
AMIGA6
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