Publications associées à Théorie des contraintes

Simulating intra-household interactions for in- and out-of-home activity scheduling

Michel Bierlaire, Timothy Michael Hillel, Negar Rezvany

Various interactions, time arrangements, and constraints exist for individuals scheduling their day as a member of a household, which affect their in-home as well as out-of-home activity schedule. However, the existing activity-based models are mostly base ...

Pergamon-Elsevier Science Ltd2023

Optimizing Sales Forecasting, Inventory, Pricing and Sourcing Decisions

Yara Kayyali El Alem

In this thesis we address various factors that contribute both theoretically and practically to mitigating supply demand mismatches. The thesis is composed of three chapters, where each chapter is an independent scientific paper. In the first paper, we dev ...

EPFL2023

Utilizing additive manufacturing and mass customization under capacity constraints

Ralf Seifert, Anna Timonina-Farkas, Rachel Agnès Laetitia Rosemonde Marie Lacroix

Additive manufacturing (AM), originally used for prototyping, is increasingly adopted for custom final part production across different industries. However, printing speed and production volume are two barriers for the adoption of AM for product customizat ...

2023

Towards ‘Fourth Paradigm’ Spectral Sensing

Marilyne Andersen, Forrest Simon Webler, Manuel Spitschan

Reconstruction algorithms are at the forefront of accessible and compact data collection. In this paper, we present a novel reconstruction algorithm, SpecRA, that adapts based on the relative rarity of a signal compared to previous observations. We leverag ...

2022

Clustering and Informative Path Planning for 3D Gas Distribution Mapping: Algorithms and Performance Evaluation

Alcherio Martinoli, Chiara Ercolani, Lixuan Tang, Ankita Arun Humne

Chemical gas dispersion can represent a severe threat to human and animal lives, as well as to the environment. Constructing a map of the distribution of gas in a fast and reliable manner is critical to ensure accurate monitoring of at-risk facilities and ...

2022

CAFS: Cost-Aware Features Selection Method for Multimodal Stress Monitoring on Wearable Devices

David Atienza Alonso, Maria del Carmen Sandi Perez, Adriana Arza Valdes, João Pedro de Matos Rodrigues, Niloofar Momeni

Objective: Today, stress monitoring on wearable devices is challenged by the tension between high-detection accuracy and battery lifetime driven by multimodal data acquisition and processing. Limited research has addressed the classification cost on multim ...

2022

Industry 4.0 Technologies and Customer-centricity for Digital Supply Chains

Rachel Agnès Laetitia Rosemonde Marie Lacroix

The last few years have experienced the emergence of Industry 4.0 (I4.0), ultra-customization, and the explosion of demand for ethical, fair trade, and sustainable consumption. Organizations have therefore started a digital transformation of their SCs and ...

EPFL2021

Form follows availability – Designing structures through reuse

Corentin Jean Dominique Fivet, Gennaro Senatore, Jan Friedrich Georg Brütting

This work proposes a new direction in structural design: the synthesis of structures through the reuse of elements. Reusing structural elements reduces the environmental impacts of building structures because it avoids sourcing new material, it reduces was ...

International Center for Numerical Methods in Engineering (CIMNE)2019

Impacts of Constraints and Constraint Handling Strategies for Multi-Objective Mechanical Design Problems

Jürg Alexander Schiffmann, Cyril Picard

Multi-objective optimization tools are becoming increasingly popu-lar in mechanical engineering and allow decision-makers to better understand the inevitable trade-offs. Mechanical design problems can however combine properties that make the use of optimiz ...

2018

Inventory dynamics in process industries: An empirical investigation

Ralf Seifert, Philipp Urs Moser, Olov Isaksson

Process industry firms have thrived in recent decades, but changes in the markets are currently putting both growth and profitability at risk. In this context, inventory management is increasingly viewed as an essential lever for creating a sustainable com ...

Elsevier2017

A test of inventory models with permissible delay in payment

Ralf Seifert, Olov Isaksson, Daniel Seifert

Contrary to the long-standing view in the finance literature that firms should maximise payment delays, research in operations management suggests that long payment delays can be suboptimal. In this study, we reconcile these two views by applying a seconda ...

2017

Supply Chain Disruption Risk Management : Modeling Risk Mitigation Strategies

Florian Christopher Matthias Lücker

It is well established that firms are exposed to the risk of supply chain disruptions. Many firms build risk mitigation strategies in order to increase the resilience of their supply chains. In this dissertation we present three essays that study operation ...

EPFL2016

Dynamic Product Portfolio Management with Life Cycle Considerations

Ralf Seifert, Jean-Sébastien Tancrez, Isik Bicer

We consider a portfolio of products in which each product probabilistically transitions through various life cycle stages. The evolution through these life cycle stages is impacted by both marketing support and product launch decisions, which are bound by ...

2016

Inventory Leanness and the Financial Performance of the Firm

Ralf Seifert, Olov Isaksson

This paper examines the financial consequences that inventory leanness has on firm performance. We conduct an econometric analysis using 4324 publicly traded US manufacturing companies for the period 1980-2008. Using an instrumental variable fixed effects ...

2014

Operational Decisions and Supply Chain Dynamics : An Empirical Investigation

Olov Isaksson

While traditional research in operations management has focused on mathematical models for improving the flow of physical goods and information, this dissertation takes a quantitative empirical approach. With three distinct research projects it revisits ce ...

EPFL2013

OLTP in Wonderland -- Where do cache misses come from in major OLTP components?

Anastasia Ailamaki, Pinar Tözün

For several decades, online transaction processing has been one of the main applications that drives innovations in the data management ecosystem, and in turn the database and computer architecture communities. Despite the novel approaches from industry an ...

ACM2013

Soft Cell Simulator: A tool to study Soft Multi-Cellular Robots

Dario Floreano, Andrea Maesani, Jürg Markus Germann, Manuel Stöckli

Modular or multi-cellular robots hold the promise to adapt their morphology to task and environment. However, research in modular robotics has traditionally been limited to mechanically non-adaptive systems due to hard building blocks and rigid connection ...

2013

Design optimization of a 2D blade by means of milling tool path

François Avellan, Cécile Münch-Alligné, Christian Vessaz, Christophe Tournier

In a conventional design and manufacturing process, turbine blades are modeled based on reverse engineering or on parametric modeling with Computer Fluids Dynamics (CFD) optimization. Then, only raises the question of the manufacturing of the blades. As th ...

2013

A new formulation of the two-dimensional cutting-stock problem with consideration of demand planning

Naoufel Cheikhrouhou, Omar Ayadi

This paper focuses on the two dimensional rectangular non-oriented guillotine cutting stock problem (TDRCSP) in which many pieces with different dimensions need to be cut with different quantities in order to satisfy customers' orders. In order to maximise ...

2012

Low-Power Circuits and Systems Design for Data Acquisition and Transmission in a Wireless Cortical Implant

Vahid Majidzadeh Bafar

Minimally invasive monitoring of the electrical activity of specific cortical areas using implantable microsystems offers the promise of diagnosing neurological diseases, as well as detecting and identifying neural activity patterns which are specific to a ...

EPFL2012