Search results for "automatic"
showing 10 items of 730 documents
An optimal energy efficient cooperative retransmission MAC scheme in wireless networks
2011
While the benefits of cooperative diversity have been well studied in the literature, cooperative MAC protocol design has also attracted much attention recently. In the single-relay Cooperative Automatic Repeat reQuest (C-ARQ) protocol, the best relay node is selected in a distributed manner by relays using different backoff time before packet retransmission. However, this relay selection scheme does not work efficiently in a dense network scenario, due to possible high collision probability among different contending relays. In this paper, we propose an optimized relay selection scheme to maximize system energy efficiency by reducing collision probability. The energy efficiency performance…
Invalid Syntax: NooJ Assisted Automatic Detection of Errors in Auxiliaries and Past Participles in Italian
2017
The work targets two areas of Italian morphosyntax: auxiliary selection (AS) and past participle agreement (PPA). In selecting such inflectional morphemes, learners of Italian commit frequent errors, even after a long period of constant study. We aim to enclose AS and PPA within the boundaries of NLP in order that a tool can be developed with a twofold purpose: first, it helps experts to build specific computer drills regarding AS and PPA; second, it assists self-taught learners in verifying whether their periphrastic sentences in Italian are well-turned. This area of Computer-Assisted Language Learning is currently poorly investigated. Further research might substantiate the importance of …
Hybrid 3D-ResNet Deep Learning Model for Automatic Segmentation of Thoracic Organs at Risk in CT Images
2020
In image radiation therapy, accurate segmentation of organs at risk (OARs) is a very essential task and has clinical applications in cancer treatment. The segmentation of organs close to lung, breast, or esophageal cancer is a routine and time-consuming process. The automatic segmentation of organs at risk would be an essential part of treatment planning for patients suffering radiotherapy. The position and shape variation, morphology inherent and low soft tissue contrast between neighboring organs across each patient’s scans is the challenging task for automatic segmentation of OARs in Computed Tomography (CT) images. The objective of this paper is to use automatic segmentation of the orga…
Implementation of a PLC Field Analyzer on a G3 Modem Platform
2021
Nowadays, power line communications (PLC) are a widely used technology in distribution grids, both for automatic meter reading and automation applications. PLC performances (in terms of capacity, coverage, robustness, and data transmission rate) can be significantly affected by electrical network topologies, connected loads and disturbances. Thus, utilities and modem manufacturers are increasing their interest in electrical network characterization. In this framework, a software tool is proposed in this paper to measure received signal and noise levels. As case study, it is implemented on a G3 PLC transceiver, widely used for smart metering purposes. In this way, a PLC channel characterizat…
Unsupervised clustering method for pattern recognition in IIF images
2017
Autoimmune diseases are a family of more than 80 chronic, and often disabling, illnesses that develop when underlying defects in the immune system lead the body to attack its own organs, tissues, and cells. Diagnosis of autoimmune pathologies is based on research and identification of antinuclear antibodies (ANA) through indirect immunofluorescence (IIF) method and is performed by analyzing patterns and fluorescence intensity. We propose here a method to automatically classify the centromere pattern based on the grouping of centromeres on the cells through a clustering K-means algorithm. The described method was tested on a public database (MIVIA). The results of the test showed an Accuracy…
Sensorless control of permanent magnet synchronous motors for wide speed range applications
2006
This paper deals with sensorless control of Interior Permanent Magnet Synchronous Motors (IPMS) based on the estimation of speed and rotor angular position. The above estimate is based on the injection of high frequency stator currents able to generate a signal similar to that generated by a resolver connected to the axis of the motor. A new digital algorithm has been designed to demodulate the above signal whose implementation can be carried out on the same DSP that processes the control algorithm. In this paper a new scheme of speed and angular position estimator is proposed and justified on the theoretic point of view. The experimental results here shown validate the effectiveness of the…
A Multi-Relay Cooperative Automatic Repeat Request Protocol in Wireless Networks
2010
This paper proposes a Multi-relay Cooperative Automatic Repeat ReQuest protocol (MC-ARQ) for IEEE 802.11 based wireless networks. The proposed distributed relay selection scheme not only selects the best relays but also solves the collision problem among multiple contending relays, by sorting the relays in the network according to their instantaneous channel quality with the destination node. No prior information or explicit signaling among relay nodes is required. Both analytical and simulation results show that significant benefits can be achieved with the MC-ARQ protocol, compared with both the recently proposed PRCSMA scheme and the original non-cooperative DCF scheme.
IMPROVING CNC MACHINE TOOLS ACCURACY USING MODELING AND COMPUTER SIMULATION TECHNIQUES
2007
Abstract The position was one of the first parameters that required the introduction of automatic control process. One of the most representative applications is represented by the feed drives of the computer numerically controlled (CNC) machine tools. Today, it is possible to use computer simulation techniques in analysing and synthesising position control systems. Thus, the behaviour of the CNC machine tools feed drives can be treated much more realistically. It is the purpose of this paper to show how simulation can be used to accurately represent, predict and improve the performance of a CNC machine tool feed servo drives.
Frequency Regulation of Hybrid Power System by Optimized Adaptive Fuzzy PID Controller
2020
In this study, an adaptive fuzzy PID (AFPID) regulator has been proposed for frequency control of hybrid power system. For controller parameter optimization, an upgraded Whale Optimization Algorithm (WOA) has been employed. In the proposed Upgraded WOA (UWOA) technique, a cosine function is incorporated in the original WOA for determining control parameter to manage the position of whales throughout optimization procedure. Furthermore, scaling factors are employed in original WOA to adjust the travel of whales in search procedure. Proposed UWOA technique is employed to design an AFPID controller for frequency regulation of a hybrid power system It is demonstrated that UWOA technique out per…
Application of a genetic algorithm in calibration of traffic microsimulation models
2017
This chapter describes the genetic algorithm-based calibration procedure for a microscopic traffic simulation model focusing on freeways and modern roundabouts. For both case studies, the genetic algorithm tool in MATLAB® was applied in order to reach the convergence between the outputs from Aimsun microscopic simulator and the observed data. The automatic interaction with Aimsun software was implemented through an original external Python script. Results showed that the genetic algorithm-based calibration procedure gave a better match to the observed data than simple manual calibration and the efficiency of the calibration efforts resulted significantly improved. At last, the calbrated mod…