774 research outputs found
Design and implementation of a trust calculation method for network components
Today’s organizations rely on internal or cloud-infrastructures to manage their data and their products. Due to the increasing importance and complexity of these infrastructures, there is the need to implement a reliable way to monitor the trustworthiness of the devices that are part of it. It is important to establish trust within the nodes of a single or multiple security domains to enhance the security of an enterprise’s infrastructure.
This thesis aims to develop and evaluate a method to measure and calculate a trust score for each node and security domain of a network infrastructure. This method will be based on a centralized verifier that collects and verifies all the security and performance-based evidence from the nodes that compose the infrastructure. The evidence verification process is based on remote attestation through the use of a hardware root of trust. Moreover, this method allows the exchange of trust scores with other security domains: this enhances inter-domain communication trustworthiness.
The main advantages of this method compared to similar ones found in the literature are the possibility of an inter-domain trust exchange, the use of remote attestation, and its adaptability to work with different kinds of infrastructure. Furthermore, the tests confirmed that the method responds quickly in case of a vulnerable node
Land Use Change in two watersheds under agriculture use in the mountains of Rio de Janeiro State - Brazil: an approach to support the agriculture sustainable planning.
Mudanças de uso da terra em bacias hidrográficas.
bitstream/item/87953/1/DOC-139-Mudancas-Uso-Terra-BH.pd
A methodology to assess the impact of agricultural practices in the Water-Energy-Food Nexus.
By 2030, it is estimated that the world population will be 8.3 billion people, increasing the pression in energy, water, food, land use and mineral extraction, especially in the developing world. These estimates indicate the immediate need to adopt interventions that can minimize these impacts. There is a lot of talk about sustainability, but it is still rare to make the results of integrated evaluations available on various topics. When considering the integrated Nexus Food-Water-Energy (F-W-E) assessment, this fact is even more challenging. Considering the importance of the agricultural sector in Brazil and the existence of areas in different stages of degradation, it becomes strategic for interventions that can generate socio-economic and environmental benefits and positive impacts to the tripod F-W-E. Thus, the present proposal will be based on the Ribeirão das Lajes dam (RJ), a core area for the water supply of the second largest city in Brazil - Rio de Janeiro. A methodological approach able to generate an integrated assessment tool to evaluate the impact of agriculture practices in the Nexus F - W - E will be presented. We used secondary official dada as the main input for this tool. One of the reasons is to make it accessible for different stakeholders and decision makers. It can help to get better decisions regarding land use intervention - which may be technical or political
Corrections to AdS Black Hole Thermodynamics from Higher-Derivative Supergravity
We study four-derivative corrections to five-dimensional minimal gauged
supergravity. We evaluate the on-shell action of the AdS black hole
solution with two independent angular momenta and one electric charge at linear
order in the corrections. After imposing supersymmetry, we are able to recast
the action in terms of the supersymmetric chemical potentials and match the
result obtained from the dual superconformal index on the second sheet. To
achieve this, we exploit the freedom to implement field redefinitions to recast
the action in a much simpler form, as well as the fact that the two-derivative
solution is enough. We use the on-shell action to determine the corrections to
the black hole thermodynamics, including those to the entropy and the charges.
We then specialize to the supersymmetric and extremal case and find a simple
expression for the microcanonical entropy. In particular, for the case with one
independent angular momentum the corrections are entirely encoded in the dual
superconformal anomaly coefficients. We corroborate this result for the entropy
by constructing the corrected near-horizon solution and applying Wald's
formula.Comment: 52 pages; v2: new results on general angular momenta and Legendre
transform of the susy on-shell action added, clarifications added, typos
fixed, references adde
Boundary terms and conserved charges in higher-derivative gauged supergravity
We address some issues in higher-derivative gauged supergravity with
Chern-Simons terms, focusing on the five-dimensional case. We discuss the
variational problem with Dirichlet boundary conditions as well as holographic
renormalization in asymptotically locally AdS spacetimes, and derive the
corresponding boundary terms. We then employ Wald's formalism in order to
define conserved charges associated to local symmetries (diffeomorphisms and
U(1) gauge transformations), taking into account the effect of generic gauge
Chern-Simons terms. We prove that the first law of black hole mechanics and the
quantum statistical relation hold in this setup. Chern-Simons terms also lead
us to distinguish between Noether charges and Page (or Komar) charges which
satisfy the Gauss law. We make use of the latter to compute corrections to the
angular momentum and electric charge of the supersymmetric black hole in
AdS from its corrected near-horizon geometry. This also allows us to derive
the microcanonical form of the entropy as a function of the conserved charges
relying entirely on the near-horizon geometry. Finally, we comment on
four-derivative gauged supergravity in four dimensions, showing that field
redefinitions permit to simplify the action at linear order in the corrections,
so that the equations of motion are those of the two-derivative theory.Comment: 39 page
Decoupled Sampling-Based Motion Planning for Multiple Autonomous Marine Vehicles
There is increasing interest in the deployment and operation of multiple autonomous marine vehicles (AMVs) for a number of challenging scientific and commercial operational mission scenarios. Some of the missions, such as geotechnical surveying and 3D marine habitat mapping, require that a number of heterogeneous vehicles operate simultaneously in small areas, often in close proximity of each other. In these circumstances safety, reliability, and efficient multiple vehicle operation are key ingredients for mission success. Additionally, the deployment and operation of multiple AMVs at sea are extremely costly in terms of the logistics and human resources required for mission supervision, often during extended periods of time. These costs can be greatly minimized by automating the deployment and initial steering of a vehicle fleet to a predetermined configuration, in preparation for the ensuing mission, taking into account operational constraints. This is one of the core issues addressed in the scope of the Widely Scalable Mobile Underwater Sonar Technology project (WiMUST), an EU Horizon 2020 initiative for underwater robotics research. WiMUST uses a team of cooperative autonomous ma- rine robots, some of which towing streamers equipped with hydrophones, acting as intelligent sensing and communicat- ing nodes of a reconfigurable moving acoustic network. In WiMUST, the AMVs maintain a fixed geometric formation through cooperative navigation and motion control. Formation initialization requires that all the AMVs start from scattered positions in the water and maneuver so as to arrive at required target configuration points at the same time in a completely au- tomatic manner. This paper describes the decoupled prioritized vehicle motion planner developed in the scope of WiMUST that, together with an existing system for trajectory tracking, affords a fleet of vehicles the above capabilities, while ensuring inter- vehicle collision and streamer entanglement avoidance. Tests with a fleet of seven marine vehicles show the efficacy of the system planner developed.Peer reviewe
Potencial de uso de métricas de paisagem para relacionar a dinâmica de uso da terra com a qualidade da água: estudo de caso na região serrana do Estado do Rio de Janeiro.
A configuração de uma paisagem está relacionada à dinâmica do uso e cobertura da terra na qual ela se insere. Este fato afeta diretamente a sua estrutura e confere padrões espaciais aos fragmentos florestais, bem como aos usos predominantes da terra de uma determinada região. Essa configuração espacial reflete tanto nos processos naturais como a qualidade da água, quanto nos aspectos socioeconômicos associados. Por isso, faz-se necessário o entendimento dessa distribuição espacial; o que pode ser obtido a partir do cálculo de métricas de paisagem. No presente trabalho foram analisadas 16 métricas de paisagem em uma bacia de drenagem na região montanhosa do Rio de Janeiro, denominada Pito Aceso - afluente do Rio Grande, que por sua vez é afluente do Rio Paraíba do Sul. Posteriormente aos cálculos das métricas, foi realizada uma análise por componentes principais onde foi possível observar as métricas que se mostraram mais eficientes para evidenciar a estrutura da paisagem em análise. Como estudos da qualidade da água também foram realizados na bacia, a próxima etapa do trabalho será associar esses resultados aos resultados de qualidade da água, de forma a demonstrar a potencialidade do uso dessas análises para subsidiar o planejamento sustentável das paisagens bem como dos recursos hídricos
SHPIA 2.0: An Easily Scalable, Low-Cost, Multi-purpose Smart Home Platform for Intelligent Applications
Sensors, electronic devices, and smart systems have invaded the market and our daily lives. As a result, their utility in smart home contexts to improve the quality of life, especially for the elderly and people with special needs, is getting stronger and stronger. Therefore, many systems based on smart applications and intelligent devices have been developed, for example, to monitor people’s environmental contexts, help in daily-life activities, and analyze their health status. However, most existing solutions have drawbacks related to accessibility and usability. They tend to be expensive and lack generality and interoperability. These solutions are not easily scalable and are typically designed for specific constrained scenarios. This paper tackles such drawbacks by presenting SHPIA 2.0, an easily scalable, low-cost, multi-purpose smart home platform for intelligent applications. It leverages low-cost Bluetooth Low Energy (BLE) devices featuring both BLE connected and BLE broadcast modes, to transform common objects of daily life into smart objects. Moreover, SHPIA 2.0 allows the col- lection and automatic labeling of different data types to provide indoor monitoring and assistance. Specifically, SHPIA 2.0 is designed to be adaptable to different home-based application scenarios, including human activity recognition, coaching systems, and occupancy detection and counting. The SHPIA platform is open source and freely available to the scientific community, fostering collaboration and innovation
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