999 resultados para macchine relativistiche, user-mode linux, marionnet, virtualità, relativizzazione
Resumo:
Una macchina relativistica è una macchina il cui tempo scorre ad una velocità diversa da quella del tempo reale. Macchine di questo tipo possono essere utili ad esempio per simulare tempi di trasferimento dei dati più veloci, oppure per testare protocolli di sincronizzazione degli orologi. La possibilità di definire la velocità del tempo virtuale è stata aggiunta a User-Mode Linux. Grazie ad una modifica a Marionnet che include un'interfaccia grafica è stato reso semplice il processo di creazione di reti di macchine virtuali relativistiche.
Resumo:
The purpose of this document is to create a modest integration guide for embedding a Linux Operating System on ZedBoard development platform, based on Xilinx’s Zynq-7000 All Programmable System on Chip which contains a dual core ARM Cortex-A9 and a 7 Series FPGA Artix-7. The integration process has been structured in four chapters according to the logic generation of the different parts that compose the embedded system. With the intention of automating the generation process of a complete Linux distribution specific for ZedBoard platform, BuildRoot development platform it is used. Once the embedding process finished, it was decided to add to the system the required functionalities for adding support for IEEE1588 Standard for Precision Clock Synchronization Protocol for Networked Measurement and Control Systems, through a user space Linux program which implements the protocol. That PTP user space implementation program has been cross-compiled, executed on target and tested for evaluating the functionalities added. RESUMEN El propósito de este documento es crear una modesta guía de integración de un sistema operativo Linux para la plataforma de desarrollo ZedBoard, basada en un System on Chip del fabricante Xilinx llamado Zynq-7000. Este System on Chip está compuesto por un procesador de doble núcleo ARM Cortex-A9 y una FPGA de la Serie 7 equiparable a una Artix-7. El proceso de integración se ha estructurado en cuatro grandes capítulos que se rigen según el orden lógico de generación de las distintas partes por las que el sistema empotrado está compuesto. Con el ánimo de automatizar el proceso de creación de una distribución de Linux específica para la plataforma ZedBoard, se ha utilizado la plataforma de desarrollo BuildRoot. Una vez terminado el proceso de integración del sistema empotrado, se procedió a dar dotar al sistema de las funcionalidades necesarias para dar soporte al estándar de sincronización de relojes en redes de área local, PTP IEEE1588, a través de una implementación del mismo en un programa de lado de usuario el cual ha sido compilado, ejecutado y testeado para evaluar el correcto funcionamiento de las funcionalidades añadidas.
Resumo:
Anàlisi d'una PDA amb funcions de telefonia mòbil, en el nostre cas la HTC TyTN, valorant la seva usabilitat a l'hora de realitzar la seva configuració per a l'ús d'un servei, tant en un mode d'usuari normal com avançat. S'analitza també el sistema operatiu de què disposa (Windows Mobile 6.0 Professional).
Resumo:
At head of cover-title on t. II: Jäneckes bibliotheken, reihe B.
Resumo:
"Vorrede" signed: Joh. Gottfried Steinhäuser.
Resumo:
The development of the distributed information measurement and control system for optical spectral research of particle beam and plasma objects and the execution of laboratory works on Physics and Engineering Department of Petrozavodsk State University are described. At the hardware level the system is represented by a complex of the automated workplaces joined into computer network. The key element of the system is the communication server, which supports the multi-user mode and distributes resources among clients, monitors the system and provides secure access. Other system components are formed by equipment servers (CАМАC and GPIB servers, a server for the access to microcontrollers MCS-196 and others) and the client programs that carry out data acquisition, accumulation and processing and management of the course of the experiment as well. In this work the designed by the authors network interface is discussed. The interface provides the connection of measuring and executive devices to the distributed information measurement and control system via Ethernet. This interface allows controlling of experimental parameters by use of digital devices, monitoring of experiment parameters by polling of analog and digital sensors. The device firmware is written in assembler language and includes libraries for Ethernet-, IP-, TCP- и UDP-packets forming.
Resumo:
Fast spreading unknown viruses have caused major damage on computer systems upon their initial release. Current detection methods have lacked capabilities to detect unknown viruses quickly enough to avoid mass spreading and damage. This dissertation has presented a behavior based approach to detecting known and unknown viruses based on their attempt to replicate. Replication is the qualifying fundamental characteristic of a virus and is consistently present in all viruses making this approach applicable to viruses belonging to many classes and executing under several conditions. A form of replication called self-reference replication, (SR-replication), has been formalized as one main type of replication which specifically replicates by modifying or creating other files on a system to include the virus itself. This replication type was used to detect viruses attempting replication by referencing themselves which is a necessary step to successfully replicate files. The approach does not require a priori knowledge about known viruses. Detection was accomplished at runtime by monitoring currently executing processes attempting to replicate. Two implementation prototypes of the detection approach called SRRAT were created and tested on the Microsoft Windows operating systems focusing on the tracking of user mode Win32 API system calls and Kernel mode system services. The research results showed SR-replication capable of distinguishing between file infecting viruses and benign processes with little or no false positives and false negatives. ^
Resumo:
Fast spreading unknown viruses have caused major damage on computer systems upon their initial release. Current detection methods have lacked capabilities to detect unknown virus quickly enough to avoid mass spreading and damage. This dissertation has presented a behavior based approach to detecting known and unknown viruses based on their attempt to replicate. Replication is the qualifying fundamental characteristic of a virus and is consistently present in all viruses making this approach applicable to viruses belonging to many classes and executing under several conditions. A form of replication called self-reference replication, (SR-replication), has been formalized as one main type of replication which specifically replicates by modifying or creating other files on a system to include the virus itself. This replication type was used to detect viruses attempting replication by referencing themselves which is a necessary step to successfully replicate files. The approach does not require a priori knowledge about known viruses. Detection was accomplished at runtime by monitoring currently executing processes attempting to replicate. Two implementation prototypes of the detection approach called SRRAT were created and tested on the Microsoft Windows operating systems focusing on the tracking of user mode Win32 API system calls and Kernel mode system services. The research results showed SR-replication capable of distinguishing between file infecting viruses and benign processes with little or no false positives and false negatives.
Resumo:
With the current complexity of communication protocols, implementing its layers totally in the kernel of the operating system is too cumbersome, and it does not allow use of the capabilities only available in user space processes. However, building protocols as user space processes must not impair the responsiveness of the communication. Therefore, in this paper we present a layer of a communication protocol, which, due to its complexity, was implemented in a user space process. Lower layers of the protocol are, for responsiveness issues, implemented in the kernel. This protocol was developed to support large-scale power-line communication (PLC) with timing requirements.
Resumo:
Dans un contexte où le monde du travail s’internationalise et où l’innovation est fondamentale, les organisations d’aujourd’hui doivent structurer le travail en tenant compte des distances géographiques et du besoin de bien performer dans les tâches reliées aux différents projets. Toutefois, le recours à des projets innovants et l’accès à des moyens de communication ne sont pas des conditions suffisantes pour assurer une performance adéquate. Différents facteurs, comme les compétences adaptées au travail virtuel et le degré de virtualité qui sépare les gens, doivent être pris en compte pour favoriser l’atteinte d’une bonne performance. De plus, afin de sélectionner les candidats qui seront en mesure de bien performer dans ce contexte, le recours à des outils d’évaluation appropriés et disponibles dans plusieurs langues est essentiel. Cette thèse présente en premier lieu un processus de traduction, d’adaptation et de validation en français et en anglais d’un outil en allemand visant l’évaluation des compétences requises lorsque le travail est organisé en mode distribué. Un premier article présente les limites fréquemment observées dans les études qui effectuent de telles adaptations. Un deuxième article met ensuite en lumière l’importance relative d’un ensemble de compétences liées à deux types de performances individuelles appropriées au travail en projet virtuel. Les résultats montrent que la créativité, l’autonomie, l’intégrité, la loyauté et la minutie sont directement liées à la performance proactive. Il est cependant nécessaire de prendre en compte l’effet positif de la perception de collaboration et l’effet négatif du degré de virtualité pour comprendre comment les compétences que constituent la motivation à apprendre, l’autonomie, l’intégrité, la loyauté et la minutie agissent sur la performance adaptative. En somme, cette thèse propose d’abord un processus rigoureux permettant l’adaptation, la traduction et la validation d’outils dans plusieurs langues. Ce processus permet d’éviter les limites auxquelles se buteraient des méthodes plus simples dans un contexte international où il est primordial d’avoir une très grande confiance en l’équivalence des instruments. Cette thèse représente également un avancement intéressant en ce qui a trait à la compréhension des différents déterminants de la performance individuelle lorsque le travail est organisé en projets virtuels. Des recommandations sont présentées afin de favoriser la performance individuelle, et des pistes de recherches futures sont également amenées pour continuer à approfondir les connaissances sur le sujet.
Resumo:
There is increasing pressure to capture of video within Higher Education. Although much research has looked at how communication technologies enhance information transfer during playback of video, consideration of technical issues seems incongruous if we do not consider how presentation mode affects information assimilated by, and satisfaction of, learners with a range of individual differences, and from a range of different backgrounds. This paper considers whether a relationship exists between the media and presentation mode used in recorded content, and the level of information assimilation and satisfaction perceived by learners with a range of individual differences. Results aim to inform learning practitioners whether generic delivery is justified, or whether tailoring content delivery enhances the experience of specific learner groups.
Resumo:
This article presents and analyses some aspects of Georges Perec's composition as shown in his book Life: a user's manual (1978). Starting with the image of a ""book-library"", composed by some of Perec's literary 'models', and discussing the theory of intextertuality and rewriting, we propose to analyse some possible approximations between Perec and Flaubert, especially in the latter's Bouvard and Pecuchet (1881).
Resumo:
Tailoring specified vibration modes is a requirement for designing piezoelectric devices aimed at dynamic-type applications. A technique for designing the shape of specified vibration modes is the topology optimization method (TOM) which finds an optimum material distribution inside a design domain to obtain a structure that vibrates according to specified eigenfrequencies and eigenmodes. Nevertheless, when the TOM is applied to dynamic problems, the well-known grayscale or intermediate material problem arises which can invalidate the post-processing of the optimal result. Thus, a more natural way for solving dynamic problems using TOM is to allow intermediate material values. This idea leads to the functionally graded material (FGM) concept. In fact, FGMs are materials whose properties and microstructure continuously change along a specific direction. Therefore, in this paper, an approach is presented for tailoring user-defined vibration modes, by applying the TOM and FGM concepts to design functionally graded piezoelectric transducers (FGPT) and non-piezoelectric structures (functionally graded structures-FGS) in order to achieve maximum and/or minimum vibration amplitudes at certain points of the structure, by simultaneously finding the topology and material gradation function. The optimization problem is solved by using sequential linear programming. Two-dimensional results are presented to illustrate the method.
Resumo:
Passive techniques as an alternative to artificial cooling can bring important energy, environmental, financial, operational and qualitative benefits. However, regions such as the wet tropics can reach high levels of thermal stress in which passive means alone are unable to provide appropriate thermal comfort standards for some parts of the year. Despite a great accumulation of empirical information on the passive performance of houses for either free-running or conditioned modes, very little work has been done on the thermal performance of buildings that can operate with a mixed-running strategy in warm-humid climates. Buildings with such design features are able to balance the needs for comfort, privacy, and energy efficiency during different periods of the year. As free-running and conditioned modes are believed by many to be 'opposite' approaches, and have been presented as separate strategies, this paper demonstrates that not all parameters are directly opposite and a possible dual-mode integrated operation can be used for warm-humid locations for maximum comfort and minimum energy requirements. For this purpose, simulation runs using ESP-R (University of Strathclyde, ESRU, UK) were based on the climate data of Darwin (Australia) and on the ventilation styles of the house: free running and conditioned. Design features applicable to both, i.e. for a dual mode operation could be identified and the differences between conditioned and free running were demonstrated and proved not to be totally conflicting and therefore suitable for a dual mode operation. Different daily usage profiles (five use patterns were defined), and zoning of sleeping and living areas are presented. The dual mode use patterns compared to the base case house, for all the user possibilities, had improved performances of 17-52%, when compared to the free-running mode and 66-98% when compared to the conditioned mode. Simulation runs using other warm-humid climates (Miami, USA; Sao Luis, Brazil; Kuala Lumpur, Malaysia) were also conducted and compared to the results found for Darwin. (C) 2002 Elsevier Science Ltd. All rights reserved.