Homogeneously non-idling schedules of unit-time jobs on identical parallel machines

International audienceIn this paper, we study the basic homogeneous mm-machine scheduling problem where weakly dependent unit-time jobs have to be scheduled within the time windows between their release dates and due dates so that, for any subset of machines, the set of the time units at which at least one machine is busy, is in interval. We first introduce the notions of pyramidal structure, kk-hole, mm-matching, preschedule, kk-schedule and schedule for this problem. Then we provide a feasibility criteria for a preschedule. The key result of the paper is then to provide a structural necessary and sufficient condition for an instance of the problem to be feasible. We conclude by giving the directions of ongoing works and by bringing open questions related to different variants of the basic non-idling mm-machine scheduling problem

Resource Cost Aware Scheduling Problems

Managing the consumption of non-renewable and/or limited resources has become an important issue in many different settings. In this dissertation we explore the topic of resource cost aware scheduling. Unlike the purely scheduling problems, in the resource cost aware setting we are not only interested in a scheduling performance metric, but also the cost of the resources consumed to achieve a certain performance level. There are several ways in which the cost of non-renewal resources can be added into a scheduling problem. Throughout this dissertation we will focus in the case where the resource consumption cost is added, as part of the objective, to a scheduling performance metric such as weighted completion time and weighted tardiness among others. In our work we make several contributions to the problem of scheduling with non-renewable resources. For the specific setting in which only energy consumption is the important resource, our contributions are the following. We introduce a model that extends the previous energy cost models by allowing more general cost functions that can be job-dependent. We further generalize the problem by allowing arbitrary precedence constraints and release dates. We give approximation algorithms for minimizing an objective that is a combination of a scheduling metric, namely total weighted completion time and total weighted tardiness, and the total energy consumption cost. Our approximation algorithm is based on an interval-and-speed-indexed IP formulation. We solve the linear relaxation of this IP and we use this solution to compute a schedule. We show that these algorithms have small constant approximation ratios. Through experimental analysis we show that the empirical approximation ratios are much better than the theoretical ones and that in fact the solutions are close to optimal. We also show empirically that the algorithm can be used in additional settings not covered by the theoretical results, such as using flow time or an online setting, with good approximation and competitiveness ratios

Resource management for extreme scale high performance computing systems in the presence of failures

2018 Summer.Includes bibliographical references.High performance computing (HPC) systems, such as data centers and supercomputers, coordinate the execution of large-scale computation of applications over tens or hundreds of thousands of multicore processors. Unfortunately, as the size of HPC systems continues to grow towards exascale complexities, these systems experience an exponential growth in the number of failures occurring in the system. These failures reduce performance and increase energy use, reducing the efficiency and effectiveness of emerging extreme-scale HPC systems. Applications executing in parallel on individual multicore processors also suffer from decreased performance and increased energy use as a result of applications being forced to share resources, in particular, the contention from multiple application threads sharing the last-level cache causes performance degradation. These challenges make it increasingly important to characterize and optimize the performance and behavior of applications that execute in these systems. To address these challenges, in this dissertation we propose a framework for intelligently characterizing and managing extreme-scale HPC system resources. We devise various techniques to mitigate the negative effects of failures and resource contention in HPC systems. In particular, we develop new HPC resource management techniques for intelligently utilizing system resources through the (a) optimal scheduling of applications to HPC nodes and (b) the optimal configuration of fault resilience protocols. These resource management techniques employ information obtained from historical analysis as well as theoretical and machine learning methods for predictions. We use these data to characterize system performance, energy use, and application behavior when operating under the uncertainty of performance degradation from both system failures and resource contention. We investigate how to better characterize and model the negative effects from system failures as well as application co-location on large-scale HPC computing systems. Our analysis of application and system behavior also investigates: the interrelated effects of network usage of applications and fault resilience protocols; checkpoint interval selection and its sensitivity to system parameters for various checkpoint-based fault resilience protocols; and performance comparisons of various promising strategies for fault resilience in exascale-sized systems

LIPIcs, Volume 261, ICALP 2023, Complete Volume

LIPIcs, Volume 261, ICALP 2023, Complete Volum

Innovation for maintenance technology improvements

A group of 34 submitted entries (32 papers and 2 abstracts) from the 33rd meeting of the Mechanical Failures Prevention Group whose subject was maintenance technology improvement through innovation. Areas of special emphasis included maintenance concepts, maintenance analysis systems, improved maintenance processes, innovative maintenance diagnostics and maintenance indicators, and technology improvements for power plant applications

Federal Register

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii

Engenharia de sistemas baseada em modelos: um sistema para o tráfego & ambiente

Doutoramento em Gestão IndustrialThe contemporary world is crowded of large, interdisciplinary, complex systems made of other systems, personnel, hardware, software, information, processes, and facilities. The Systems Engineering (SE) field proposes an integrated holistic approach to tackle these socio-technical systems that is crucial to take proper account of their multifaceted nature and numerous interrelationships, providing the means to enable their successful realization. Model-Based Systems Engineering (MBSE) is an emerging paradigm in the SE field and can be described as the formalized application of modelling principles, methods, languages, and tools to the entire lifecycle of those systems, enhancing communications and knowledge capture, shared understanding, improved design precision and integrity, better development traceability, and reduced development risks. This thesis is devoted to the application of the novel MBSE paradigm to the Urban Traffic & Environment domain. The proposed system, the GUILTE (Guiding Urban Intelligent Traffic & Environment), deals with a present-day real challenging problem “at the agenda” of world leaders, national governors, local authorities, research agencies, academia, and general public. The main purposes of the system are to provide an integrated development framework for the municipalities, and to support the (short-time and real-time) operations of the urban traffic through Intelligent Transportation Systems, highlighting two fundamental aspects: the evaluation of the related environmental impacts (in particular, the air pollution and the noise), and the dissemination of information to the citizens, endorsing their involvement and participation. These objectives are related with the high-level complex challenge of developing sustainable urban transportation networks. The development process of the GUILTE system is supported by a new methodology, the LITHE (Agile Systems Modelling Engineering), which aims to lightening the complexity and burdensome of the existing methodologies by emphasizing agile principles such as continuous communication, feedback, stakeholders involvement, short iterations and rapid response. These principles are accomplished through a universal and intuitive SE process, the SIMILAR process model (which was redefined at the light of the modern international standards), a lean MBSE method, and a coherent System Model developed through the benchmark graphical modeling languages SysML and OPDs/OPL. The main contributions of the work are, in their essence, models and can be settled as: a revised process model for the SE field, an agile methodology for MBSE development environments, a graphical tool to support the proposed methodology, and a System Model for the GUILTE system. The comprehensive literature reviews provided for the main scientific field of this research (SE/MBSE) and for the application domain (Traffic & Environment) can also be seen as a relevant contribution.O mundo contemporâneo é caracterizado por sistemas de grande dimensão e de natureza marcadamente complexa, sócio-técnica e interdisciplinar. A Engenharia de Sistemas (ES) propõe uma abordagem holística e integrada para desenvolver tais sistemas, tendo em consideração a sua natureza multifacetada e as numerosas inter-relações que advêm de uma quantidade significativa de diferentes pontos de vista, competências, responsabilidades e interesses. A Engenharia de Sistemas Baseada em Modelos (ESBM) é um paradigma emergente na área da ES e pode ser descrito como a aplicação formal de princípios, métodos, linguagens e ferramentas de modelação ao ciclo de vida dos sistemas descritos. Espera-se que, na próxima década, a ESBM desempenhe um papel fundamental na prática da moderna Engenharia de Sistemas. Esta tese é dedicada à aplicação da ESBM a um desafio real que constitui uma preocupação do mundo actual, estando “na agenda” dos líderes mundiais, governantes nacionais, autoridades locais, agências de investigação, universidades e público em geral. O domínio de aplicação, o Tráfego & Ambiente, caracteriza-se por uma considerável complexidade e interdisciplinaridade, sendo representativo das áreas de interesse para a ES. Propõe-se um sistema (GUILTE) que visa dotar os municípios de um quadro de desenvolvimento integrado para adopção de Sistemas de Transporte Inteligentes e apoiar as suas operações de tráfego urbano, destacando dois aspectos fundamentais: a avaliação dos impactos ambientais associados (em especial, a poluição atmosférica e o ruído) e a divulgação de informação aos cidadãos, motivando o seu envolvimento e participação. Estes objectivos relacionam-se com o desafio mais abrangente de desenvolver redes de transporte urbano sustentáveis. O processo de desenvolvimento do sistema apoia-se numa nova metodologia (LITHE), mais ágil, que enfatiza os princípios de comunicação contínua, feedback, participação e envolvimento dos stakeholders, iterações curtas e resposta rápida. Estes princípios são concretizados através de um processo de ES universal e intuitivo (redefinido à luz dos padrões internacionais), de um método simples e de linguagens gráficas de modelação de referência (SysML e OPDs/OPL). As principais contribuições deste trabalho são, na sua essência, modelos: um modelo revisto para o processo da ES, uma metodologia ágil para ambientes de desenvolvimento baseados em modelos, uma ferramenta gráfica para suportar a metodologia proposta e o modelo de um sistema para as operações de tráfego & ambiente num contexto urbano. Contribui-se ainda com uma cuidada revisão bibliográfica para a principal área de investigação (ES/ESBM) e para o domínio de aplicação (Tráfego & Ambiente)

Best Environmental Management Practice for the Waste Management Sector

The way communities generate and manage their waste plays an absolutely key role in their ability to use resources efficiently. While making European economy more resource efficient and circular requires a large spectrum of actions, a huge potential for saving resources lays in improving waste management at local level in Europe. On the basis of an in-depth analysis of the actions implemented by frontrunner organisations in the waste management sector, this report describes a set of best practices with high potential for broad uptake. They are called Best Environmental Management Practices (BEMPs) and aim to help local authorities in charge of waste management and waste management companies move towards circular economy. The BEMPs, identified in close cooperation with a technical working group comprising experts from the sector, cover the waste management areas which determine the most the overall waste management performance: setting a waste management strategy, promoting waste prevention, establishing an efficient waste collection that supports re-use and recycling, and stimulating waste and product re-use. Certain areas of waste treatment are also covered. The BEMPs address mainly the management of municipal solid waste, but also of construction and demolition waste and healthcare waste. Additionally, the report provides a set of environmental performance indicators that organisations can use to assess their waste management performance and monitor progress as well as benchmarks of excellence that give an indication of the levels achieved by best performers. The report presents a wide range of information (environmental benefits, economics, case studies, references, etc.) for each of the best practices and aims to provide inspiration and guidance to organisations of the sector. In addition, the report will be the technical basis for the development of an EMAS (EU Eco-Management and Audit Scheme) Sectoral Reference Document on Best Environmental Management Practice for the Waste Management sector according to Article 46 of Regulation (EC) No 1221/2009 (EMAS Regulation).JRC.B.5-Circular Economy and Industrial Leadershi

Fragments of Sobriquet

As exposited and demonstrated through the work and studies of sociologists Pierre Bourdieu, and Gary Stevens, among others, architects have traditionally represented but a small and demographically homogenous portion of the population at large. What does this mean for design? For architecture? The thesis is a picaresque story of the experience of architecture and the education of architecture, through the lens of someone who believes themselves quite different from the typical homogeneity. Questions of difference, meaning, what design means to whom, and who has say in determining and arbitrating that answer, are all probed freely and experimentally. The thesis explores the idea of architecture as narrative, and attempts to place emphasis on its narrative effects, as opposed to its physical or social, or other effects. The thesis explores architecture’s ability to probe, to explore solutions, to explore problems, to explore possibilities, and to reveal what may be hidden. The thesis is about exploring the idea that architecture is the means by which we create narratives for our lives, for our spaces, for the world around us. Through it, we explore the notion of architecture itself as a sobriquet, a sobriquet of our societies and of our worlds. These explorations are then juxtaposed and layered upon the demographic homogeneity of architects and architecture, which allows us to question the very field in which we practice