Search results for "scheduling"

Robust Energy Scheduling in Vehicle-to-Grid Networks

2017

The uncertainties brought by intermittent renewable generation and uncoordinated charging behaviors of EVs pose great challenges to the reliable operation of power systems, which motivates us to explore the integration of robust optimization with energy scheduling in V2G networks. In this article, we first introduce V2G robust energy scheduling problems and review the stateof- the art contributions from the perspectives of renewable energy integration, ancillary service provision, and proactive demand-side participation in the electricity market. Second, for each category of V2G applications, the corresponding problem formulations, robust solution concepts, and design approaches are describ…

Joint routing and per-flow fairness in wireless multihop networks

2008

In wireless multihop networks communication between two end-nodes is carried out by hopping over multiple short wireless links. Traditional CSMA/CA based media access control does not work satisfactory in a multihop scenario, since an intended target of a communication may be subject to mutual interference imposed by concurrent transmissions from nodes which cannot directly sense each other, causing unfair throughput allocation. Although TDMA seems to be a more promising solution, careful transmission scheduling is needed in order to achieve error-free communication and fairness. In our previous work, a TDMA scheduling algorithm has been proposed that schedules the transmissions in a fair m…

Implementazione di funzioni aggiuntive per la rappresentazione e la gestione ottimizzata di risorse energetiche distribuite in un distretto energetic…

2013

Il presente Rapporto descrive le attività svolte dal personale del DEIM dell’Università degli Studi Palermo nell’ambito della prima fase delle attività di ricerca dal titolo: “Implementazione di funzioni aggiuntive per la rappresentazione e la gestione ottimizzata di risorse energetiche distribuite in un distretto energetico. Simulazione di scenari in ambiente integrato”, oggetto dell’Accordo di Collaborazione tra ENEA e DEIM sottoscritto in data 25 marzo 2013. Scopo del presente accordo di collaborazione è la definizione di funzioni aggiuntive per i vari componenti del distretto energetico già descritti e modellati in un apposito software nella scorsa annualità. Le simulazioni sono state s…

Evaluating a hierarchical approach to landscape-level harvest scheduling

2018

Forest planning at the landscape level has the potential to become a large intractable problem. In Finland, Metsähallitus (the state enterprise that manages federally owned land) creates strategic plans to determine the appropriate harvest level. While these plans are feasible, they are not implementable in practice as the harvests are scattered temporally and spatially. Requiring that harvests be organized both temporally and spatially for practical implementation can result in an intractable problem. Through a hierarchical approach, the problem can be organized into steps in which the intractable problem is broken down into smaller easily solvable parts. As an approximation technique, th…

Schedulability analysis of window-constrained execution time tasks for real-time control

2003

Feasibility tests for hard real-time systems provide information about the schedulability of a set of tasks. However, this information is a yes or no answer whether the task set achieves the test or not. From the system design point of view, it would be useful to have more information, for example, how much can one vary some task parameters, such as computation time, without jeopardizing the system feasibility. The aim of the work is to provide a method to determine how much a task can increase its computation time, maintaining the system feasibility under a dynamic priority scheduling. This extra time can be determined not only in all the task activations, but in n of a window of m task in…

Project duration evaluated using affine arithmetic

2016

A civil engineering work can be performed by organizing the available resources (manpower, equipment and materials) in many different ways. Each different configuration results in a realization time and a cost that a building company has to bear. To produce reliable duration forecasts and money savings, it is essential to take into account all the uncertainties involved in the project operations. Generally, since it is impractical to process numerous uncertain variables - also undefined from a statistical point of view -, traditional probabilistic methods involve application difficulties for complex environments such as construction sites. To properly handle this issue, the authors propose …

2014

This paper presents a mathematical model for robust production planning. The model helps fashion apparel suppliers in making decisions concerning allocation of production orders to different production plants characterized by different lead times and production costs, and in proper time scheduling and sequencing of these production orders. The model aims at optimizing these decisions concerning objectives of minimal production costs and minimal tardiness. It considers several factors such as the stochastic nature of customer demand, differences in production and transport costs and transport times between production plants in different regions. Finally, the model is applied to a case study.…

Scheduling Domestic Shiftable Loads in Smart Grids: A Learning Automata-Based Scheme

2017

In this paper, we consider the problem of scheduling shiftable loads, over multiple users, in smart grids. We approach the problem, which is becoming increasingly pertinent in our present energy-thirsty society, using a novel distributed game-theoretic framework. From a modeling perspective, the distributed scheduling problem is formulated as a game, and in particular, a so-called “Potential” game. This game has at least one pure strategy Nash Equilibrium (NE), and we demonstrate that the NE point is a global optimal point. The solution that we propose, which is the pioneering solution that incorporates the theory of Learning Automata (LA), permits the total supplied loads to approach the p…

Assessing agro-hydrological models to schedule irrigation for crops of Mediterranean Environment

2008

Two Simple Constructive algorithms for the Distributed Assembly Permutation Flowshop Scheduling Problem

2014

Nowadays, it is necessary to improve the management of complex supply chains which are often composed of multi-plant facilities. This paper proposes a Distributed Assembly Permutation Flowshop Scheduling Problem (DAPFSP). This problem is a generalization of the Distributed Permutation Flowshop Scheduling Problem (DPFSP) presented by Naderi and Ruiz (Comput Oper Res, 37(4):754–768, 2010). The first stage of the DAPFSP is composed of f identical production factories. Each center is a flowshop that produces jobs that have to be assembled into final products in a second assembly stage. The objective is to minimize the makespan. Two simple constructive algorithms are proposed to solve the proble…