Hierarchical production planning for discrete event manufacturing systems.

Ngo-Tai Fong.Thesis (Ph.D.)--Chinese University of Hong Kong, 1996.Includes bibliographical references (leaves 158-168).Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Manufacturing Systems: An Overview --- p.1Chapter 1.2 --- Previous Research --- p.3Chapter 1.3 --- Motivation --- p.5Chapter 1.4 --- Outline of the Thesis --- p.8Chapter 2 --- Preliminaries --- p.11Chapter 2.1 --- Problem Formulation: Deterministic Production Planning --- p.11Chapter 2.2 --- Markov Chain --- p.15Chapter 2.3 --- Problem Formulation: Stochastic Production Planning --- p.18Chapter 2.4 --- Some Lemmas --- p.24Chapter 3 --- Open-Loop Production Planning in Stochastic Flowshops --- p.26Chapter 3.1 --- Introduction --- p.26Chapter 3.2 --- Limiting Problem --- p.29Chapter 3.3 --- Weak-Lipschitz Continuity --- p.34Chapter 3.4 --- Constraint Domain Approximation --- p.41Chapter 3.5 --- Asymptotic Analysis: Initial States in Sε --- p.47Chapter 3.6 --- Asymptotic Analysis: Initial States in S \ Sε --- p.61Chapter 3.7 --- Concluding Remarks --- p.70Chapter 4 --- Feedback Production Planning in Deterministic Flowshops --- p.72Chapter 4.1 --- Introduction --- p.72Chapter 4.2 --- Assumptions --- p.75Chapter 4.3 --- Optimal Feedback Controls --- p.76Chapter 4.3.1 --- The Case c1 < c2+ --- p.78Chapter 4.3.2 --- The Case c1 ≥ c2+ --- p.83Chapter 4.4 --- Concluding Remarks --- p.88Chapter 5 --- Feedback Production Planning in Stochastic Flowshops --- p.90Chapter 5.1 --- Introduction --- p.90Chapter 5.2 --- Original and Limiting Problems --- p.91Chapter 5.3 --- Asymptotic Optimal Feedback Controls for pε --- p.97Chapter 5.3.1 --- The Case c1 < c2+ --- p.97Chapter 5.3.2 --- The Case c1 ≥ c2+ --- p.118Chapter 5.4 --- Concluding Remarks --- p.124Chapter 6 --- Computational Evaluation of Hierarchical Controls --- p.126Chapter 6.1 --- Introduction --- p.126Chapter 6.2 --- The Problem and Control Policies under Consideration --- p.128Chapter 6.2.1 --- The Problem --- p.128Chapter 6.2.2 --- Hierarchical Control (HC) --- p.131Chapter 6.2.3 --- Kanban Control (KC) --- p.133Chapter 6.2.4 --- Two-Boundary Control (TBC) --- p.137Chapter 6.2.5 --- "Similarities and Differences between HC, KC, and TBC" --- p.141Chapter 6.3 --- Computational Results --- p.142Chapter 6.4 --- Comparison of HC with Other Polices --- p.145Chapter 6.5 --- Concluding Remarks --- p.151Chapter 7 --- Conclusions and Future Research --- p.153Bibliography --- p.15

Overview on: sequencing in mixed model flowshop production line with static and dynamic context

In the present work a literature overview was given on solution techniques considering basic as well as more advanced and consequently more complex arrangements of mixed model flowshops. We first analyzed the occurrence of setup time/cost; existing solution techniques are mainly focused on permutation sequences. Thereafter we discussed objectives resulting in the introduction of variety of methods allowing resequencing of jobs within the line. The possibility of resequencing within the line ranges from 1) offline or intermittent buffers, 2) parallel stations, namely flexible, hybrid or compound flowshops, 3) merging and splitting of parallel lines, 4) re-entrant flowshops, to 5) change job attributes without physically interchanging the position. In continuation the differences in the consideration of static and dynamic demand was studied. Also intermittent setups are possible, depending on the horizon and including the possibility of resequencing, four problem cases were highlighted: static, semi dynamic, nearly dynamic and dynamic case. Finally a general overview was given on existing solution methods, including exact and approximation methods. The approximation methods are furthermore divided in two cases, know as heuristics and methaheuristic

A Keyword, Taxonomy and Cartographic Research Review of Sustainability Concepts for Production Scheduling in Manufacturing Systems

The concept of sustainability is defined as composed of three pillars: social, environmental, and economic. Social sustainability implies a commitment to equity in terms of several “interrelated and mutually supportive” principles of a “sustainable society”; this concept includes attitude change, the Earth’s vitality and diversity conservation, and a global alliance to achieve sustainability. The social and environmental aspects of sustainability are related in the way sustainability indicators are related to “quality of life” and “ecological sustainability”. The increasing interest in green and sustainable products and production has influenced research interests regarding sustainable scheduling problems in manufacturing systems. This study is aimed both at reducing pollutant emissions and increasing production efficiency: this topic is known as Green Scheduling. Existing literature research reviews on Green Scheduling Problems have pointed out both theoretical and practical aspects of this topic. The proposed work is a critical review of the scientific literature with a three-pronged approach based on keywords, taxonomy analysis, and research mapping. Specific research questions have been proposed to highlight the benefits and related objectives of this review: to discover the most widely used methodologies for solving SPGs in manufacturing and identify interesting development models, as well as the least studied domains and algorithms. The literature was analysed in order to define a map of the main research fields on SPG, highlight mainstream SPG research, propose an efficient view of emerging research areas, propose a taxonomy of SPG by collecting multiple keywords into semantic clusters, and analyse the literature according to a semantic knowledge approach. At the same time, GSP researchers are provided with an efficient view of emerging research areas, allowing them to avoid missing key research areas and focus on emerging ones

Multicriteria hybrid flow shop scheduling problem: literature review, analysis, and future research

This research focuses on the Hybrid Flow Shop production scheduling problem, which is one of the most difficult problems to solve. The literature points to several studies that focus the Hybrid Flow Shop scheduling problem with monocriteria functions. Despite of the fact that, many real world problems involve several objective functions, they can often compete and conflict, leading researchers to concentrate direct their efforts on the development of methods that take consider this variant into consideration. The goal of the study is to review and analyze the methods in order to solve the Hybrid Flow Shop production scheduling problem with multicriteria functions in the literature. The analyses were performed using several papers that have been published over the years, also the parallel machines types, the approach used to develop solution methods, the type of method develop, the objective function, the performance criterion adopted, and the additional constraints considered. The results of the reviewing and analysis of 46 papers showed opportunities for future researchon this topic, including the following: (i) use uniform and dedicated parallel machines, (ii) use exact and metaheuristics approaches, (iv) develop lower and uppers bounds, relations of dominance and different search strategiesto improve the computational time of the exact methods,  (v) develop  other types of metaheuristic, (vi) work with anticipatory setups, and (vii) add constraints faced by the production systems itself

A simheuristic algorithm for solving an integrated resource allocation and scheduling problem

Modern companies have to face challenging configuration issues in their manufacturing chains. One of these challenges is related to the integrated allocation and scheduling of resources such as machines, workers, energy, etc. These integrated optimization problems are difficult to solve, but they can be even more challenging when real-life uncertainty is considered. In this paper, we study an integrated allocation and scheduling optimization problem with stochastic processing times. A simheuristic algorithm is proposed in order to effectively solve this integrated and stochastic problem. Our approach relies on the hybridization of simulation with a metaheuristic to deal with the stochastic version of the allocation-scheduling problem. A series of numerical experiments contribute to illustrate the efficiency of our methodology as well as their potential applications in real-life enterprise settings

Classification of the Existing Knowledge Base of OR/MS Research and Practice (1990-2019) using a Proposed Classification Scheme

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordOperations Research/Management Science (OR/MS) has traditionally been defined as the discipline that applies advanced analytical methods to help make better and more informed decisions. The purpose of this paper is to present an analysis of the existing knowledge base of OR/MS research and practice using a proposed keywords-based approach. A conceptual structure is necessary in order to place in context the findings of our keyword analysis. Towards this we first present a classification scheme that relies on keywords that appeared in articles published in important OR/MS journals from 1990-2019 (over 82,000 articles). Our classification scheme applies a methodological approach towards keyword selection and its systematic classification, wherein approximately 1300 most frequently used keywords (in terms of cumulative percentage, these keywords and their derivations account for more than 45% of the approx. 290,000 keyword occurrences used by the authors to represent the content of their articles) were selected and organised in a classification scheme with seven top-level categories and multiple levels of sub-categories. The scheme identified the most commonly used keywords relating to OR/MS problems, modeling techniques and applications. Next, we use this proposed scheme to present an analysis of the last 30 years, in three distinct time periods, to show the changes in OR/MS literature. The contribution of the paper is thus twofold, (a) the development of a proposed discipline-based classification of keywords (like the ACM Computer Classification System and the AMS Mathematics Subject Classification), and (b) an analysis of OR/MS research and practice using the proposed classification

Commande optimale stochastique appliquée aux systèmes manufacturiers avec des sauts semi-Markoviens

Les travaux de ce mémoire sont constitués de deux parties principales. La première partie tente de formuler un nouveau modèle du problème de commande optimale stochastique de systèmes sur un horizon fini. Les systèmes considérés sont soumis à des phénomènes aléatoires dits sauts de perturbation qui sont modélisés par un processus semi-Markovien. Ces sauts de perturbation traduits par des taux de transition dépendent de l’état du système et du temps. Par conséquent, le problème de commande est formulé comme un problème d’optimisation dans un environnement stochastique. La deuxième partie vise à modéliser des systèmes de production flexible (SPF). Dans ce mémoire, ces SPF se composent de plusieurs machines en parallèles, ou en série, ou d’une station de travail (une machine représentative). Ces machines sont sujettes à des pannes et à des réparations aléatoires. L’objectif de la modélisation est de déterminer les taux de production u(t) de ces machines en satisfaisant les fluctuations de demande d(t) sur un horizon fini. Dans ce mémoire, nous avons : (a) proposé un nouveau modèle du problème d’optimisation dans un environnement stochastique sur un horizon fini pour deux cas; avec taux d’actualisation (ρ > 0) et sans taux d’actualisation (ρ = 0); (b) modélisé des SPF en déterminant une stratégie de commande plus réaliste incluant stratégie de production; (c) présenté des exemples numériques à l’aide d’une méthode de Kushner et Dupuis (2001)

Available-to-promise (ATP) systems: a classification and framework for analysis

Available-to-promise (ATP) systems deal with a number of managerial decisions related to order capture activities in a company, including order acceptance/rejection, due date setting, and resource scheduling. These different but interrelated decisions have often been studied in an isolated manner, and, to the best of our knowledge, no framework has been presented to integrate them into the broader perspective of order capture. This paper attempts to provide a general framework for ATP-related decisions. By doing so, we: (1) identify the different decision problems to be addressed; (2) present the different literature-based models supporting related decisions into a coherent framework; and (3) review the main contributions in the literature for each one of these. We first describe different approaches for order capture available in the literature, depending on two parameters related to the application context of ATP systems, namely the inclusion of explicit information about due dates in the decision model, and the level of integration among decisions. According to these parameters, up to six approaches for ATP-related decisions are identified. Secondly, we show the subsequent decision problems derived from the different approaches, and describe the main issues and key references involving each one of these decision problems. Finally, a number of conclusions and future research lines are discussed.Ministerio de Ciencia e Innovación DPI2007-6134

Cloud manufacturing – scheduling as a service for sheet metal manufacturing

Cloud manufacturing refers to a new concept of using centralized cloud computing for manufacturing information systems to support distributed and dynamic collaborative manufacturing environment. The core of cloud manufacturing is to provide service to geographically distributed manufacturers centralized services. This paper introduces a cloud based production scheduling system for sheet metal manufacturing and discusses the requirements of scheduling as a service. A genetic algorithm based scheduling application has been developed to serve distributed manufacturing lines in form of cloud manufacturing. The characteristics of the prototype system are described and performance estimates are tested.fi=vertaisarvioitu|en=peerReviewed