Search results for "Node"
showing 10 items of 1701 documents
Formal verification of a Cooperative Automatic Repeat reQuest MAC protocol
2012
Author's version of an article published in the journal: Computer Standards & Interfaces. Also available from the publisher at: http://dx.doi.org/10.1016/j.csi.2011.12.001 Cooperative communications, in which a relay node helps the source node to deliver its packets to the destination node, are able to obtain significant benefits in terms of transmission reliability, coverage extension and energy efficiency. A Cooperative Automatic Repeat reQuest (C-ARQ) MAC protocol has been recently proposed to exploit cooperative diversity at the MAC layer. in this paper, we validate the integrity and the validity of the C-ARQ protocol using formal methods. The protocol logic is modeled in SDL and implem…
Advanced Monitoring Systems Based on Battery-Less Asset Tracking Modules Energized through RF Wireless Power Transfer
2020
Asset tracking involving accurate location and transportation data is highly suited to wireless sensor networks (WSNs) featuring battery-less nodes that can be deployed in virtually any environment and require little or no maintenance. In response to the growing demand for advanced battery-less sensor tag solutions, this article presents a system for identifying and monitoring the speeds of assets in a WSN with battery-less tags that receive all their operating energy through radio frequency (RF) wireless power transfer (WPT) architecture, and a unique measurement approach to generate time-domain speed readouts. The assessment includes performance characteristics and key features of a syste…
Intestinal Involvement in Kawasaki Disease
2018
Objectives To describe a case of Kawasaki disease with intestinal involvement and to analyze other published reports to define clinical characteristics, diagnostic issues, and therapeutic approaches of gastrointestinal involvement in Kawasaki disease. Study design A computerized search without language restriction was conducted using PubMed and SCOPUS. An article was considered eligible for inclusion in the systematic review if it reported data on patient(s) with intestinal involvement in Kawasaki disease. Our case was also included in the analysis. Results Thirty-three articles reporting 48 cases of Kawasaki disease with intestinal involvement were considered. Fever, abdominal pain, and vo…
First occurrence of the needle-spined urchin Diadema setosum (Leske, 1778) (Echinodermata, Diadematidae) in the southern Mediterranean Sea
2022
The first occurrence of Diadema setosum in the southern Mediterranean waters is recorded from the shores of Libya and Egypt, through the input by citizens’ science. The expansion of this invasive sea urchin in the Mediterranean basin is briefly discussed.
Acute pancreatitis in children. An Italian multicentre study
2002
Abstract Aim . To evaluate the clinical, morphological and aetiological aspects of acute pancreatitis in children in Italy. Patients . The hospital records of 50 consecutive patients with acute pancreatitis observed in 5 Italian Pediatric Departments were reviewed. Results . A total of 25 males and 25 females (median age 10.5 years, range 2–17) were studied. Of these patients, 48 (96%) had abdominal pain. The pancreatitis was associated with biliary disease in 10 patients (20%); it was due to viral infection in 6 patients (12%), pancreatic duct abnormalities in 4 (8%), familial chronic pancreatitis in 3 (6%), trauma in 5 (10%) and other causes in 5 (10%); the pancreatitis was of unknown ori…
A backward sweep method for power flow solution in distribution networks
2010
Abstract A methodology for the analysis of radial or weakly meshed distribution systems supplying voltage dependent loads is here developed. The solution process is iterative and, at each step, loads are simulated by means of impedances. Therefore, at each iteration, it is necessary to solve a network made up only of impedances; for this kind of network, all the voltages and currents can be expressed as linear functions of a single unknown current (in radial systems) or of two unknown currents for each independent mesh (for meshed systems). The methodology has been called “backward” since the unique equation, in case of radial network, and the linear system of equations, in case of meshed n…
Effects and Benefits of Node Sharing Strategies in HPC Batch Systems
2019
Processor manufacturers today scale performance by increasing the number of cores on each CPU. Unfortunately, not all HPC applications can efficiently saturate all cores of a single node, even if they successfully scale to thousands of nodes. For these applications, sharing nodes with other applications can help to stress different resources on the nodes to more efficiently use them. Previous work has shown that the performance impact of node sharing is very application dependent but very little work has studied its effects within batch systems and for complex parallel application mixes. Administrators therefore typically fear the complexity of running a batch system supporting node sharing…
Anatomic Posterolateral Knee Reconstructions Require a Popliteofibular Ligament Reconstruction Through a Tibial Tunnel
2010
Background: No biomechanical study has been performed analyzing the merits of reconstructing the popliteofibular ligament (PFL) through a tibial tunnel with an anatomic reconstruction of the posterolateral knee. Hypothesis: There is no difference in an anatomic posterolateral knee reconstruction with or without a PFL reconstruction placed through a tibial tunnel in restoring knee motion to the intact, uninjured state, and the knee is not overconstrained with this reconstruction. Study Design: Controlled laboratory study. Methods: Eight paired knees were tested in the intact state and then sectioned to simulate a grade III posterolateral knee injury. The reconstruction for the first paired …
Heat-stable antigen is expressed by murine keratinocytes and delivers costimulatory signals in T-cell activation.
1995
Heat-stable antigen (HSA), expressed by various antigen-presenting cells (APC), has been described as a costimulatory molecule for CD4+ T cells. Recently, we observed that HSA also serves as an important costimulatory molecule on epidermal Langerhans cells (LC). During these studies, low levels of HSA staining were also detected on normal murine keratinocytes (KC). To investigate whether HSA also is involved in T-cell activation by KC, normal murine KC or the spontaneously transformed KC cell-line PAM 212 were treated with PDB or PMA to induce HSA-expression. FACS analyses showed induction of HSA expression on normal murine KC, as well as PAM 212 cells. In functional assays PDB or PMA-treat…
Optimized secure and reliable distributed data storage scheme and performance evaluation in unattended WSNs
2013
Unattended Wireless Sensor Networks (UWSNs), characterized by the absence of real-time communication between sensors and sinks, impose sensors to retain data till the next visit of a mobile sink to off-load their data. In such networks, if a sensor is compromised, data accumulated in the sensor are exposed to attackers. In addition, by holding the secret key of the compromised sensor, attackers can also learn post-compromise data accumulated by the sensor. Furthermore, once sensors stop working due to, for instance, node crash or battery depletion, all the accumulated data will be lost. In this paper, we propose a secure and reliable data distribution scheme that addresses these challenges.…