Search results for "roller"
showing 10 items of 247 documents
Novel Wireless Sensor System for Dynamic Characterization of Borehole Heat Exchangers
2011
The design and field test of a novel sensor system based in autonomous wireless sensors to measure the temperature of the heat transfer fluid along a borehole heat exchanger (BHE) is presented. The system, by means of two specials valves, inserts and extracts miniaturized wireless sensors inside the pipes of the borehole, which are carried by the thermal fluid. Each sensor is embedded in a small sphere of just 25 mm diameter and 8 gr weight, containing a transceiver, a microcontroller, a temperature sensor and a power supply. A wireless data processing unit transmits to the sensors the acquisition configuration before the measurements, and also downloads the temperature data measured by the…
Experimental Assessment of the Backoff Behavior of Commercial IEEE 802.11b Network Cards
2007
It has been observed that different IEEE 802.11 commercial cards produced by different vendors experience different performance, either when accessing alone the channel, as well as when competing against each other. These differences persist also when thorough measurement methodologies (such as RF shielding, laptop rotation, etc) are applied, and alignment of the environmental factors (same laptop models, traffic generators, etc) is carried out. This paper provides an extensive experimental characterization of the backoff operation of six commercial NIC cards. It suggests a relevant methodological approach, namely a repeatable, well defined, set of experiments, for such a characterization. …
Advanced control system for optimal filtration in submerged anaerobic MBRs (SAnMBRs)
2013
The main aim of this study was to develop an advanced controller to optimise filtration in submerged anaerobic MBRs (SAnMBRs). The proposed controller was developed, calibrated and validated in a SAnMBR demonstration plant fitted with industrial-scale hollow-fibre membranes with variable influent flow and load. This 2-layer control system is designed for membranes operating sub-critically and features a lower layer (on/off and PID controllers) and an upper layer (knowledge-based controller). The upper layer consists of a MIMO (multiple-input-multiple-output) control structure that regulates the gas sparging for membrane scouring and the frequency of physical cleaning (ventilation and back f…
An MDE Approach for Rapid Prototyping and Implementation of Dynamic Reconfigurable Systems
2015
This article presents a co-design methodology based on RecoMARTE, an extension to the well-known UML MARTE profile, which is used for the specification and automatic generation of Dynamic and Partially Reconfigurable Systems-on-Chip (DRSoC). This endeavor is part of a larger framework in which Model-Driven Engineering (MDE) techniques are extensively used for modeling and via model transformations, generating executable models, which are exploited by implementation tools to create reconfigurable systems. More specifically, the methodological aspects presented in this article are concerned with expediting the conception and implementation of the hardware platform and the integration of corre…
Reflexiones sobre el control de gestión en una economía digital
2022
En este trabajo se contextualiza el rol del control de gestión retomando sus orígenes, evolución y perspectivas futuras, especialmente en el convulsionado contexto del cambio tecnológico y de una economía digital. Para ello se caracterizan y se ejemplifican las diferencias entre el controller financiero y el de gestión. Luego de repasar las responsabilidades y tareas del controller de gestión y la importancia de su formación especializada, se presentan las implicaciones de las nuevas tecnologías y la economía digital para el desarrollo de habilidades y competencias en los controllers de gestión. Con todo ello, se concluye mostrando la importancia del esfuerzo formativo y de consolidación de…
Magnetic Levitation – Modelling, Identification and Open Loop Verification
2020
<p>The paper describes a procedure using the first principle modelling and experimental identification of the Magnetic Levitation Model CE 152. It is a modified version of the paper [1]. The difference is that the identification and verification is done in open loop and constraints logic is added in the current paper. The author optimized and simplified dynamic model to a minimum to what is needed to characterize given system for the simulation and control design purposes. Only few open-loop experiments are needed to estimate the unknown parameters. Model quality is verified in open loop where the real and simulated data are compared. The model can serve as a simulation model for some…
Network-based H∞ output feedback control for uncertain stochastic systems
2013
This paper investigates the problem of network-based Floc, output feedback control for a class of stochastic nonlinear systems. A novel model is proposed to describe the systems taken into two sides of communication channels in the network environment, which is more general than one side of communication channel. The design procedure of observer-based controller is presented, which, guarantees the asymptotic stability in the mean square of the resulting closed-loop system with an H-infinity performance. Finally, a crane example is utilized to show the effectiveness and potential of the developed techniques. Refereed/Peer-reviewed
Design methods of multithreaded architectures for multicore microcontrollers
2011
The development of electronic technology today has allowed the implementation of complex architectures, which led to the emergence of multicore processors technology. Multicore architectures are built from superscalar and multithreaded processors. Integrating new technologies in embedded applications requires the development of multicore processors that can be integrated into a smaller area like a classic microcontroller. These processors must manage fewer resources and be able to manage multiple tasks simultaneously. In this paper we present a method of modeling, simulation and evaluation of two multithreaded architectures with limited resources, which could be integrated into embedded sys…
An Experimental Testbed and Methodology for Characterizing IEEE 802.11 Network Cards
2006
It has been observed that IEEE 802.11 commercial cards produced by different vendors show a different behavior in terms of perceived throughput or access delay. Performance differences are evident both when the cards contend alone to the channel, and when heterogeneous cards contend together. Since the performance misalignment does not disappear by averaging the environmental factors (such as propagation conditions, laptop models, traffic generators, etc), it is evident that the well known throughput-fairness property of the DCF protocol is not guaranteed in actual networks. In this paper we propose a methodological approach devised to experimentally characterize the IEEE 802.11 commercial …
Exploratory approach for network behavior clustering in LoRaWAN
2021
AbstractThe interest in the Internet of Things (IoT) is increasing both as for research and market perspectives. Worldwide, we are witnessing the deployment of several IoT networks for different applications, spanning from home automation to smart cities. The majority of these IoT deployments were quickly set up with the aim of providing connectivity without deeply engineering the infrastructure to optimize the network efficiency and scalability. The interest is now moving towards the analysis of the behavior of such systems in order to characterize and improve their functionality. In these IoT systems, many data related to device and human interactions are stored in databases, as well as I…