Search results for "block"
showing 10 items of 1177 documents
Influencia algorítmica e inmutabilidad de los Smart Contacts: ¿cómo impactan estas tecnologías en la asimetría contractual?
2022
En el presente trabajo nos proponenos analizar el impacto de dos tecnologías de la Cuarta Revolución Industrial en el Derecho de los Contratos, con un marcado enfoque en los sujetos vulnerables del contrato. La primera de ellas es la “inteligencia artificial” que tiene un rol preponderante al momento de la formación, celebración y análisis del contrato. Aquí nos preguntamos cómo impactan los algoritmos en la toma de decisiones, para lo cual, haremos un paso por las neurociencias. La segunda tecnología a abordar, es la denominada blockchain que se emplea en los Smart Contracts (contratos inteligentes). El eje del análisis radicará en una de sus más destacadas características: la inmutabilida…
An Efficient and Privacy-Preserving Blockchain-Based Authentication Scheme for Low Earth Orbit Satellite Assisted Internet of Things
2022
Recently, integrating satellite networks (e.g. Low-earth-orbit satellite constellation) into the Internet of Things (IoT) ecosystem has emerged as a potential paradigm to provide more reliable, ubiquitous and seamless network services. The LEO satellite networks serves as a key enabler to transform the connectivity across industries and geographical border. Despite the convenience brought from the LEO satellite networks, it arises security concerns, in which the essential one is to secure the communication between the IoT devices and the LEO satellite network. However, some challenges inheriting from the LEO satellite networks need to be considered : 1) the dynamic topology; 2) the resource…
Aggregation and remuneration in Demand-Response with a blockchain-based framework
2020
This paper describes the possibility to use the blockchain technology for load and generation aggregation in a new distributed Demand Response (DR) service and customers remuneration system. The blockchain technology and the use of smart contracts for DR allow the creation of a distributed system in which customers can communicate directly, in a transparent, secure and traceable way, with the grid operator to provide their flexibility. In this paper, the DR problem formulation takes into account several aspects, which are periodically executed. First, the blockchain records customers’ energy consumption or production, then, the smart contract starts calculating the baseline and the potentia…
Treatment with soluble activin type IIB-receptor improves bone mass and strength in a mouse model of Duchenne muscular dystrophy
2017
Background: Inhibition of activin/myostatin pathway has emerged as a novel approach to increase muscle mass and bone strength. Duchenne muscular dystrophy (DMD) is a neuromuscular disorder that leads to progressive muscle degeneration and also high incidence of fractures. The aim of our study was to test whether inhibition of activin receptor IIB ligands with or without exercise could improve bone strength in the mdx mouse model for DMD. Methods: Thirty-two mdx mice were divided to running and non-running groups and to receive either PBS control or soluble activin type IIB-receptor (ActRIIB-Fc) once weekly for 7 weeks. Results: Treatment of mdx mice with ActRIIB-Fc resulted in significantly…
Janus Nanostructures from ABC/B Triblock Terpolymer Blends
2019
Lamella-forming ABC triblock terpolymers are convenient building blocks for the synthesis of soft Janus nanoparticles (JNPs) by crosslinking the B domain that is &ldquo
Detection of Duplicated Regions in Tampered Digital Images by Bit-Plane Analysis
2009
In this paper we present a new method for searching duplicated areas in a digital image. The goal is to detect if an image has been tampered by a copy-move process. Our method works within a convenient domain. The image to be analyzed is decomposed in its bit-plane representation. Then, for each bitplane, block of bits are encoded with an ASCII code, and a sequence of strings is analyzed rather than the original bit-plane. The sequence is lexicographically sorted and similar groups of bits are extracted as candidate areas, and passed to the following plane to be processed. Output of the last planes indicates if, and where, the image has been altered.
Evolutionary approach to coverage testing of IEC 61499 function block applications
2015
The paper addresses the problem of coverage testing of industrial automation software represented in the IEC 61499 standard, one of the recent standards for distributed control system design. Contrary to model-based testing (MBT), the paper focuses on implementation coverage, not model coverage. An approach based on evolutionary algorithms is presented which generates coverage test suites for both basic and composite IEC 61499 function blocks. It employs two third-party tools, FBDK and EvoSuite. The evaluation of the approach was performed on a set of control applications for two lab-scale demonstration plants. Results show that the approach is applicable and shows good performance at least…
AES/FPGA Encryption Module Integration for Satellite Remote Sensing Systems: LST-SW case
2020
Satellite remote sensing embedded systems need to be secure to protect data transmission between satellites and the ground station for any threat can affects the hardware of satellite and interception of data, in addition to unauthorized access to satellite system. This research proposes an approach for a secure integration of FPGA Encryption module based on the iterative looping architecture for remote sensing algorithm and especially for the LST-SW algorithm. The target hardware used in this paper is Virtex-5 XC5VLX50T FPGA from Xilinx. Hardware Description Language was used to design the complete system. The analysis of the proposed designed shows that this implementation can achieved a …
Analysis on channel bonding/aggregation for multi-channel cognitive radio networks
2010
Channel bonding/aggregation techniques, which assemble several channels together as one channel, could be used in cognitive radio networks for the purpose of achieving better bandwidth utilization. In existing work on this topic, channel bonding/aggregation is focused on the cases when primary channels are time slotted or stationary as compared with secondary users' activities. In this paper, we analyze the performance of channel bonding/aggregation strategies when primary channels are not time slotted and the time scale of primary activities is at the same level as the secondary users', given that spectrum handover is not allowed. Continuous time Markov chain models are built in order to a…
Channel Occupancy-Based Dynamic Spectrum Leasing in Multichannel CRNs: Strategies and Performance Evaluation
2016
Spectrum leasing has been proposed as an effective approach for enabling more flexible spectrum utilization in CRNs. In CRNs, a primary network (PN) which consists of multiple primary users (PUs) can lease part of the licensed spectrum to secondary users (SUs) in exchange for operational benefits. The focus of this study is to investigate how and to what extent the PN allows spectrum leasing in CRNs, considering the QoS requirements of the PN and the secondary network (SN). Correspondingly, we propose two dynamic spectrum leasing strategies, which can improve the QoS performance of SUs while ensuring sufficient remuneration for PUs. In order to dynamically adjust the portion of leased bandw…