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A New Multi-resource cumulatives Constraint with Negative Heights [chapter]

Nicolas Beldiceanu, Mats Carlsson
2002 Lecture Notes in Computer Science  
This paper presents a new s cumulative constraint which generalizes the original cumulative constraint in different ways.  ...  This paper presents a new s cumulative constraint which generalizes the original cumulative constraint in different ways.  ...  cumulated consumption of the tasks with a negative height.  ... 
doi:10.1007/3-540-46135-3_5 fatcat:ald4jhngkjaybgavma54g3au4m

A Continuous Multi-resources cumulative Constraint with Positive-Negative Resource Consumption-Production [chapter]

Nicolas Beldiceanu, Emmanuel Poder
2007 Lecture Notes in Computer Science  
This article first introduces an extension of the classical cumulative constraint: each task is no more a rectangle but rather a sequence of contiguous trapezoid sub-tasks with variable duration and heights  ...  The resource function is no more constant but is a positive or negative piecewise linear function of time.  ...  For this new task model, we came up with a polynomial algorithm to compute, for each resource, its minimum and maximum cumulated resource's profiles.  ... 
doi:10.1007/978-3-540-72397-4_16 fatcat:ji75buvfrfgqrovdguuighfteu

New filtering for the cumulative constraint in the context of non-overlapping rectangles

Nicolas Beldiceanu, Mats Carlsson, Sophie Demassey, Emmanuel Poder
2010 Annals of Operations Research  
This paper describes new filtering methods for the cumulative constraint.  ...  The second method introduces balancing knapsack constraints which relate the total height of the tasks that end at a specific timepoint with the total height of the tasks that start at the same time-point  ...  Section 4 presents a new knapsack model of the cumulative constraint which considers the available slack.  ... 
doi:10.1007/s10479-010-0731-0 fatcat:w3yyeb2euve2lc3fimg2w7rulu

Complex Constraint Abstraction: Global Constraint Visualisation [chapter]

Helmut Simonis, Abder Aggoun, Nicolas Beldiceanu, Eric Bourreau
2000 Lecture Notes in Computer Science  
Each concept captures the use of a constraint for a particular type of problem, which can be visualized in a specific way.  ...  The tools follow a general classification scheme for the use of global constraints in global constraint concepts.  ...  The disjunctive resource case is a special case of the cumulative resource with a resource limit of 1, where each task has a resource usage of 1.  ... 
doi:10.1007/10722311_13 fatcat:3pkmu7tw5bbufccr22m2mdba6u

Synchronized sweep algorithms for scalable scheduling constraints

Arnaud Letort, Mats Carlsson, Nicolas Beldiceanu
2014 Constraints  
The filtering mode achieves a significant speed-up over the decomposition into independent cumulative and precedence constraints, while the greedy mode can handle up to 1 million tasks with 64 resources  ...  This paper introduces a family of synchronized sweep based filtering algorithms for handling scheduling problems involving resource and precedence constraints.  ...  cumulative with precedences constraints.  ... 
doi:10.1007/s10601-014-9172-8 fatcat:e5hztewesvcjroj3ejvrdywbfm

A Scalable Sweep Algorithm for the cumulative Constraint [chapter]

Arnaud Letort, Nicolas Beldiceanu, Mats Carlsson
2012 Lecture Notes in Computer Science  
This paper presents a sweep based algorithm for the cumulative constraint, which can operate in filtering mode as well as in greedy assignment mode.  ...  It handles up to 1 million tasks in one single cumulative constraint in both Choco and SICStus. Partially founded by the SelfXL project (contract ANR-08-SEGI-017).  ...  Demassey for providing the fastbp constraint.  ... 
doi:10.1007/978-3-642-33558-7_33 fatcat:h3h6ymv34zbkhovku3fvjagzna

A Resource Cost Aware Cumulative [chapter]

Helmut Simonis, Tarik Hadzic
2011 Lecture Notes in Computer Science  
We motivate and introduce an extension of the well-known cumulative constraint which deals with time and volume dependent cost of resources.  ...  The CumulativeCost Constraint We start by formally defining our new constraint. It is an extension of the classical cumulative constraint [1] Cumulative(  ...  new features, like negative resource height, or non-rectangular task shapes [3, 5] .  ... 
doi:10.1007/978-3-642-19486-3_5 fatcat:qlmfagx335d3jprfd7g6szbp6m

Energy-Delay-Distortion Problem [article]

Rahul Vaze, Shreyas Chaudhari, Akshat Choube, Nitin Aggarwal
2017 arXiv   pre-print
With limited energy, the source cannot potentially transmit all bits of all packets. In addition, there is a delay cost associated with each packet.  ...  The discretized problem is a special case of a multi-partitioning problem, where each packet's utility is super-modular and the proposed greedy solution is shown to incur cost that is at most 2-times of  ...  We define a resource block as a rectangle of height (energy) e and width (slot time ). For slot j, the number of resource blocks is defined as R j .  ... 
arXiv:1711.05032v1 fatcat:to56bsdgz5gotlq6x5jukczwwy

Multi-product pricing via robust optimisation

Aurélie Thiele
2008 Journal of Revenue and Pricing Management  
We propose an approach to model demand uncertainty in pricing problems with capacitated resources that builds upon: (i) range forecasts for various product lines and (ii) bounds on the amount of the resources  ...  that can be used by the random part of the cumulative demand.  ...  We make the following contributions to the literature: K We present tractable robust counterparts to the deterministic pricing problems, with no new constraints (besides non-negativity) and 2m new decision  ... 
doi:10.1057/rpm.2008.41 fatcat:regeertdfvaupekpknxpo7mfd4

Global Constraints as Graph Properties on a Structured Network of Elementary Constraints of the Same Type [chapter]

Nicolas Beldiceanu
2000 Lecture Notes in Computer Science  
This classification is based on four basic ingredients from which one can generate almost all existing global constraints and come up with new interesting constraints.  ...  This report introduces a classification scheme for the global constraints.  ...  Cumulative scheduling constraint or scheduling under resource constraints: the cumulative constraint enforces that at each point in time, the cumulated height of the set of tasks that overlap that point  ... 
doi:10.1007/3-540-45349-0_6 fatcat:e4hjmg5t2vh2vfmxceutxkxvde

Inter- and Intraspecific Patterns in Resprouting of Trees in Undisturbed Natural Forests along an Elevational Gradient in Central Japan

Kiyoshi Umeki, Mitsuru Kawasaki, Nobuhiko Shigyo, Toshihide Hirao
2018 Forests  
We found that resprout production and parent stem growth were negatively correlated; resprouting resulted in multi-stemmed adult forms, and species with multi-stemmed forms tended to be less dominant in  ...  First, we formulated interspecific relationships among resprout production, parent stem growth, multi-stemmedness, and dominance in forest communities using a structural equation model (SEM).  ...  Because resprout production had a positive effect on multi-stemmedness, the former also had a negative effect on species' dominance through two pathways, each with a positive or negative effect.  ... 
doi:10.3390/f9110672 fatcat:j3fb2mtnejcmxcduc5b43tyjl4

Iterative construction of low-altitude UAV air route network in urban areas: Case planning and assessment

Chenchen Xu, Xiaohan Liao, Huping Ye, Huanyin Yue
2020 Journal of Geographical Sciences  
With the rapid increase of Unmanned Aircraft Vehicle (UAV) numbers, the contradiction between extensive flight demands and limited low-altitude airspace resources has become increasingly prominent.  ...  Firstly, a path-planning environment consisting of favorable spaces, obstacle spaces, and mobile communication spaces for UAV flights was pre-constructed.  ...  In the case of communication, it is a positive constraint from its positive influence; however, it can be a negative constraint when considering its weak-signal area (Xu et al., 2020) .  ... 
doi:10.1007/s11442-020-1798-4 fatcat:lc7ah2mcgjcmdpfvlil4q7dhgq

Unconventional Gas Production from Hydraulically Fractured Well-An Application of Direct Search Based Optimization Algorithm

2019 International journal of recent technology and engineering  
Application of this model to a hypothetical tight and ultra-tight unconventional gas formations indicates a significant gas production at lower treatment cost; whereas the resources do not flow without  ...  A simulation (with industrial simulators) was conducted to investigate and analyse fracture propagation behavior, under varying parameters with respect to the fracture design process, for tight gas reservoirs  ...  A negative step-length is used, if the positive step-length moves the vertex away from the unsatisfied design constraint bound(s).  ... 
doi:10.35940/ijrte.b1334.0982s1119 fatcat:st6d6cc6t5h2jgklqydezqktli

Capital- and resource-constrained project scheduling with net present value optimization

Pieter Leyman, Mario Vanhoucke
2017 European Journal of Operational Research  
Both problems include capital constraints, which force the project to always have a positive cash balance.  ...  In this paper, we study the capital-constrained project scheduling problem with discounted cash flows (CCPSPDC) and the capital-and resource-constrained project scheduling problem with discounted cash  ...  Acknowledgements We acknowledge the support provided by the "Bijzonder Onderzoeksfonds" (BOF) and by the National Bank of Belgium (NBB) for the project with contract number BOF12GOA021.  ... 
doi:10.1016/j.ejor.2016.07.019 fatcat:tzqa2nfe6ncijgtxfynxpr6xoa

MEN: Multi-Attribute Feature Selection for Face Recognition

P. Ramaraj, M. Prabakaran
2014 International Journal of Computer Applications  
The authentication mechanism is still required with more features to be used and has to be done in a short time.  ...  To overcome the problem of false positive results, we propose MEN-Mouth, Eye and Nose features based multi attribute feature selection method for face recognition.  ...  We propose a new face recognition algorithm which uses multi attribute based facial features with eccentric measures to recognize the faces.  ... 
doi:10.5120/16178-4469 fatcat:3ppv2wuwzngqdalxbrjrgpiqiq
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