Les nouvelles applications sur Internet nécessitent des garanties de qualité de service (QoS) de la part du réseau. Nous nous intéressons à deux paramètres de QoS : le temps de réponse et la gigue de bout-en-bout. Nous proposons un ordonnancement, noté FP/DP, à base de priorités fixes (FP), départageant les paquets ex aequo selon leurs priorités dynamiques (DP). La priorité fixe d'un flux reflète son degré d'importance et sa priorité dynamique est un paramètre temporel. FP/FIFO et FP/EDF sont deux exemples d'ordonnancement FP/DP. Nous déterminons des bornes déterministes sur les paramètres de QoS considérés, en utilisant l'approche par trajectoire. En monoprocesseur, nous améliorons les résultats existants et prouvons que FP/EDF domine FP/FIFO sous certaines conditions. En distribué, nous apportons de nouveaux résultats et montrons que l'approche par trajectoire est beaucoup moins pessimiste que l'approche holistique. Nos résultats sont appliqués dans une architecture DiffServ/MPLS.

The main aim of this work was to rate the usage of selected logistic methods and introduction of the operating system Kanban to the production line in the project {\clqq}C214 Top Roll`` of the company Faurecia Automotive Czech Republic, s.r.o, Interior Systems. A minor aim then was to find out the knowledge level of the Kanban method. Methodics Hypotheses: 1.The logistic flows used in the Faurecia company already function sufficiently enough, the proof of which is the stabilised production. 2.Using the operating system Kanban for functioning production, logistics and the whole company Faurecia is rather advantageous. 3.Training all the employees is a vital part in the process of introducing the operating system Kamban. Methods: deducion, situation analysis - collection of information,interviews, survey, questioning brief, modeling Structure of the practical part is following: company profile, character of pruduction and setting of the main logistical flows, determination of zones and stock sectors, process implementation and using of Kanban in the production line "C214 Top Roll". The first hypothesis can be confirmed by the situational analysis which evaluates the processing and logistic method. The individual methods {\clqq}met`` or {\clqq}nearly met`` the demands and because all the methods together partake of the production and the production has provided very good results in the previous months, we can consider the production being stabilised. The second can also be affirmed. If the production on a particular assembly line is stabilised, it is possible to introduce the Kanban method. Why not to use it if a there is a great advantage of this method in simplicity and lower production supplies which result in decreasing the total costs? It is beneficial for all participating on the production and for the Faurecia company as a whole. Third hypothesis can be confirmed as well. There has been a survey based on short questionaires and the knowledge of working and using the Kanban has been found inadequate. The best form of providing all the important information will be a training as a part of the process of introducing and using the Kanban method. Both aims have been resulted in stating possible recommendations and improvement suggestions: - production is stabilized, Kanban is possible to apply on 1.9. 2008 - training is necessary, meeting of responsible persons, control, messing, measures, - training of current and new workers, - motivation, communication improve, - system of regural records about information and control of chief (material and production planning)

Orientador: Shusaburo Motoyama / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-05T03:22:31Z (GMT). No. of bitstreams: 1 Marques_LeandroBentoSena_M.pdf: 2511927 bytes, checksum: 046043b18faff2ea54b0ccb236d8ae9b (MD5) Previous issue date: 2005 / Resumo: Neste trabalho é apresentado um estudo do desempenho do enlace direto do sistema 1xEV-DO. O estudo enfatiza o impacto da adoção de modelos de tráfegos reais tais como HTTP, FTP e WAP e de diferentes escalonadores. Através de simulação são analisados: o atraso médio dos pacotes, a vazão e percentual de perda de cada tipo de tráfego em função da carga de tráfego. É adotado neste estudo o escalonamento FIFO, com prioridade, WFQ e DRR. Os resultados mostram que o sistema 1xEV-DO padronizado permite transmissões de dados a altas taxas de bits. É mostrado, também, que a introdução de outros escalonadores podem melhorar ainda mais o desempenho do sistema / Abstract: The forward link performance study of the 1xEV- DO system is presented in this work. The study emphasizes the impact of the adoption of the real traf c mode1s such as HTTP, FTP and WAP and several different schedulers. The average packet delay, the throughput and each traf c loss percentage are analyzed through simulation in function of traf c load. It is adopted in this study schedulers FIFO, with priority, WFQ and DRR. The results show that standardized 1xEV-DO system allows data transmission at high bits rates. It is also shown that the system performance can still enhanced by introducing others schedulers / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Scheduling is extremely important for modern real-time systems. It enables several programs to run in parallel and succeed with their tasks. Many systems today are real-time systems, which means that good scheduling is highly needed. This thesis aims to evaluate the real-time scheduling algorithm earliest deadline first, newly introduced into the Linux kernel, and compare it to the already existing real-time scheduling algorithms first in, first out and round robin in the context of firm tasks. By creating a test program that can create pthreads and set their scheduling characteristics, the performance of earliest deadline first can be evaluated and compared to the others. / Schemaläggning är extremt viktigt för dagens realtidssystem. Det tillåter att flera program körs parallellt samtidigt som deras processer inte misslyckas med sina uppgifter. Idag är många system realtidssystem, vilket innebär att det finns ett ytterst stort behov för en bra schemaläggningsalgoritm. Målet med det här examensarbetet är att utvärdera schema-läggningsalgoritmen earliest deadline first som nyligen introducerats i operativsystemet Linux. Målet är även att jämföra algoritmen med två andra schemaläggningsalgoritmer (first in, first out och round robin), vilka redan är väletablerade i Linux kärnan. Det här görs med avseende på processer klassificerade som firm. Genom att skapa ett program som kan skapa pthreads med önskvärda egenskaper kan prestandan av earliest deadline first algoritmen utvärderas, samt jämföras med de andra algoritmerna.

Diploma thesis deals with creating four laboratory tasks using simulation tool OMNeT++ and Inet Framework extension. Subject matter of these designed tasks is focused on routing protocols, providing quality of service, computer networking technologies used in local area networks and comparison of active networking devices. First task contains the comparison of behaviour and routing techniques between protocols RIPv2 and OSPFv2, including the effect of dividing OSPF network into smaller areas. Second task is focused on various techniques for controlling quality of service, namely FIFO queue, PQ and WFQ. Main goal is the comparison of results, that define quality of network services. Third task compares networking technologies, Ethernet and WLAN, parameters of transmission. Fourth task offers comparison of networking devices, hub, switch and router. This paper also contains required theory of network technologies and software tools used for executing simulations.

Dans ce travail, nous nous focalisons sur l’ajout de contraintes temporelles dans les Bases de Données de Capteurs Sans Fil (BDCSF). La cohérence temporelle d’une BDCSF doit être assurée en respectant les contraintes temporelles des transactions et la validité temporelle des données, pour que les données prélevées par les capteurs reflètent fidèlement l’état réel de l’environnement. Cependant, les retards de transmission et/ou de réception pendant la collecte des données peuvent conduire au non-respect de la validité temporelle des données. Une solution de type bases de données s'avère la plus adéquate. Il faudrait pour cela faire coïncider les aspects BD traditionnelles avec les capteurs et leur environnement. À cette fin, les capteurs déployés au sein d'un réseau sans fils sont considérés comme une table d'une base de données distribuée, à laquelle sont appliquées des transactions (interrogations, mises à jour, etc.). Les transactions sur une BD de capteurs nécessitent des modifications pour prendre en compte l'aspect continu des données et l'aspect temps réel. Les travaux réalisés dans cette thèse portent principalement sur trois contributions : (i) une étude comparative des propriétés temporelles entre une collecte périodique des données avec une base de données classique et une approche de traitement des requêtes avec une BDCSF, (ii) la proposition d’un modèle de traitement des requêtes temps réel, (iii) la mise en œuvre d’une BDCSF temps réel, basée sur les techniques décrites dans la deuxième contribution. / In this thesis, we are interested in adding real-time constraints in the Wireless Sensor Networks Database (WSNDB). Temporal consistency in WSNDB must be ensured by respecting the transaction deadlines and data temporal validity, so that sensor data reflect the current state of the environment. However, delays of transmission and/or reception in a data collection process can lead to not respect the data temporal validity. A database solution is most appropriate, which should coincide with the traditional database aspects with sensors and their environment. For this purpose, the sensor in WSN is considered as a table in a distributed database, which applied transactions (queries, updates, etc.). Transactions in a WSNDB require modifications to take into account of the continuous datastream and real-time aspects. Our contribution in this thesis focus on three parts: (i) a comparative study of temporal properties between a periodic data collection based on a remote database and query processing approach with WSNDB, (ii) the proposition of a real-time query processing model, (iii) the implementation of a real time WSNDB, based on the techniques described in the second contribution.