Service level agreement framework for differentiated survivability in GMPLS-based IP-over-optical networks

In the next generation optical internet, GMPLS based IP-over-optical networks, ISPs will be required to support a wide variety of applications each having their own requirements. These requirements are contracted by means of the SLA. This paper describes a recovery framework that may be included in the SLA contract between ISP and customers in order to provide the required level of survivability. A key concern with such a recovery framework is how to present the different survivability alternatives including recovery techniques, failure scenario and layered integration into a transparent manner for customers. In this paper, two issues are investigated. First, the performance of the recovery framework when applying a proposed mapping procedure as an admission control mechanism in the edge router considering a smart-edge simple-core GMPLS-based IP/WDM network is considered. The second issue pertains to the performance of a pre-allocated restoration and its ability to provide protected connections under different failure scenarios

Using interdependency matrices to mitigate targeted attacks on interdependent networks: A case study involving a power grid and backbone telecommunications networks

Analysis of the interdependencies between interconnected critical infrastructures can help enhance the robustness of the individual infrastructures as well as the overall interconnected infrastructures. One of the most studied interdependent critical infrastructure network scenarios is a power grid connected to a backbone telecommunications network. In this interdependent infrastructure scenario, the robustness of the entire system is usually analyzed in the context of cascading failure models in the power grid. However, this paper focuses on targeted attacks, where an attack on a telecommunications network node directly affects a connected power grid node, and vice versa. Cascading failures are outside the scope of this paper because the objective is to enhance the robustness of the interconnections between the infrastructures. In order to mitigate the impacts of targeted attacks on the interdependent infrastructures, three interdependency matrices for connecting the infrastructures are specified and analyzed. The analysis identifies the interdependency matrix that best reduces the impacts of targeted attacks and the propagation of failures between the infrastructures. Additionally, the impacts of interconnecting a power grid to different telecommunications networks, each with different susceptibilities to targeted attacks, is evaluate

A novel content-based image retrieval system based on Bayesian logistic regression

In this work, a novel content-based image retrieval (CBIR) method is presented. It has been implemented and run on “Qatris IManager” [14], a system belonging to SICUBO S.L. (spin-off from University of Extremadura, Spain). The system offers some innovative visual content search tools for image retrieval from databases. It searches, manages and classifies images using four kinds of features: colour, texture, shape and user description. In a typical CBIR system, query results are a set of images sorted by feature similarities with respect to the query. However, images with high feature similarities to the query may be very different from the query in terms of semantics. This discrepancy between low-level features and high-level concepts is known as the semantic gap. The search method presented here, is a novel supervised image retrieval method, based in Bayesian Logistic Regression, which uses the information from the characteristics extracted from the images and from the user’s opinion who sets up the search. The procedure of search and learning is based on a statistical method of aggregation of preferences given by Arias-Nicolás et al. [1] and is useful in problems with both a large number of characteristics and few images. The method could be specially helpful for those professionals who have to make a decision based in images, such as doctors to determine the diagnosis of patients, meteorologists, traffic police to detect license plate, etc

Thermal and electrical stability assessment of AlGaN/GaN Metal-Oxide-Semiconductor High Electron Mobility Transistors (MOS-HEMT) with HfO2 gate dielectric.

AlGaN/GaN HEMTs and MOS-HEMTs using HfO2 as gate dielectric have been analyzed at room temperature, after STA and TC test, during off-state electrical step stress, HTRB and PBTI tests. Results showed that the leakage current in as-fabricated MOS-HEMTs decreased by 106 and the on/off ratio increased by over 104 than the HEMTs. Moreover, it was even higher after a STA test, up to 108, in the MOS-HEMTs, and the surface trapping effects were mitigated, especially if a KOH cleaning was used before HfO2 deposition. The MOS-HEMTs also showed higher electrical stability after off-state step electrical stress, HTRB and PBTI tests.pre-print732 K

Patch Plate Materials Compatibility Assessment

Lunar dust proved to be a greater problem during the Apollo missions than was originally anticipated. The highly angular, charged dust particles stuck to seals, radiators, and visors; clogged mechanisms; and abraded space suits. As reported by Apollo 12 astronaut Pete Conrad "We must have had more than a hundred hours suited work with the same equipment, and the wear was not as bad on the training suits as it is on these flight suits in just the eight hours we were out.". Dust clinging to surfaces was also transport-ed into habitable spaces leading to lung and eye irritation of the astronauts. The Apollo astronauts were on the Lunar surface less than 24 hours and experienced many dust related problems. With the Artemis program, we are planning longer stays on the surface, with more activities that have the potential to put the astronauts and equipment in contact with greater quantities of Lunar dust. The success of these missions will depend on our understanding of material interactions with Lunar dust and the development of ways to mitigate dust effects in cases where exposure to dust will lead to failure of components, unacceptable loss of power or thermal control, unacceptable loss of visibility, or health issues. Through the Lunar Surface In-novation Initiative (LSII), we are initiating a Patch Plate Materials Compatibility Assessment project. The overall goal of the three year project is to develop passive approaches to mitigate Lunar dust adhesion to surfaces for technologies that are currently at TRL levels 2-3 to bring them to TRL level 5 through ground-based assessment, culminating in a demonstration flight experiment on a Commercial Lunar Payload Services (CLPS) lander in 2022-2023. This paper discusses the detailed technical objectives and approach for this project. References: Gaier, J.R. "The Effects of Lunar Dust on EVA Systems During the Apollo Missions," NASA/TM-2005-213610/REV1, (2005), Apollo 12 Technical Crew Debriefing, December 1, 1969, pp. 10-54

State of the art in the determination of trace elements in seawater: a worldwide proficiency test

This manuscript presents the results of the International Measurement Evaluation Programme 40 (IMEP-40) study, a proficiency test (PT) which was organised to assess the worldwide performance of laboratories for the determination of trace elements in seawater. This PT supports the implementation of the European Union Water Framework Directive 2000/60/EC, which aims at achieving a long-term high level protection of the aquatic environment, covering lakes, ground water and coastal waters. Forty-six participants reported results. The test item was seawater containing the trace elements As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn. The trace elements in the test item were present in very low concentrations to mimic natural levels. The results of the participants were rated with z and zeta (zeta) scores in accordance with ISO 13528 and ISO 17043. The standard deviation for proficiency assessment, , was set at 25 % of the respective assigned values for the 12 measured elements based on previous experience with similar PTs. The low levels of the trace elements combined with the high salt concentration of the seawater made the measurements challenging. Many laboratories were unable to detect or quantify the elements and reported "lower than X" values. The percentage of satisfactory performances (expressed as z scores) ranged from 41 % (Cr, Fe) to 86 % (Mo). The PT study showed that the use of proper standard methods, like ISO 17294-2, and sensitive techniques, like inductively coupled plasma mass spectrometry (ICP-MS), contributed to performing well in this PT round

The Probability of Failure of an in Stages Constructed Embankment on Soft Soil

During construction of the first one of a twin dam in the Oosterschelde basin several instabilities occurred. Design of the construction plan of the dam was based on classical methods of analysis of stability and usually applied safety criteria. Back analysis of the failures consisted of a probabilistic analysis, indicating high overall probabilities of failure, and FEM analysis, indicating areas of large plastic deformation of the subsoil, caused by the steep setup of the sandfill in \u27the initial construction stage, resulting in too concentrated surcharge. Based on these results, it was decided to apply these methods of analysis from the beginning in the design of the construction plan for the second dam. This plan has successfully been carried out

Assessing availability and greenhouse gas emissions of lignocellulosic biomass feedstock supply – case study for a catchment in England

© 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.Feedstocks from lignocellulosic biomass (LCB) include crop residues and dedicated per¬ennial biomass crops. The latter are often considered superior in terms of climate change mitigation potential. Uncertainty remains over their availability as feedstocks for biomass provision and the net greenhouse gas emissions (GHG) during crop production. Our objective was to assess the optimal land allocation to wheat and Miscanthus in a specific case study located in England, to increase bio¬mass availability, improve the carbon balance (and reduce the consequent GHG emissions), and mini¬mally constrain grain production losses from wheat. Using soil and climate variables for a catchment in east England, biomass yields and direct nitrogen emissions were simulated with validated process-based models. A ‘Field to up-stream factory gate’ life-cycle assessment was conducted to estimate indirect management-related GHG emissions. Results show that feedstock supply from wheat straw can be supplemented beneficially with LCB from Miscanthus grown on selected low-quality soils. In our study, 8% of the less productive arable land area was dedicated to Miscanthus, increasing total LCB provision by about 150%, with a 52% reduction in GHG emission per ton LCB delivered and only a minor effect on wheat grain production (−3%). In conclusion, even without considering the likely carbon sequestration in impoverished soils, agriculture should embrace the opportunities to provide the bioeconomy with LCB from dedicated, perennial crops.Peer reviewe