Scheduling Schemes Based on Searching the Aggregated Graph of Operations Planning Sequence

2015 ◽  
Vol 809-810 ◽  
pp. 1462-1467 ◽  
Author(s):  
Krzysztof Kalinowski ◽  
Iwona Paprocka
Keyword(s):  
State Space ◽  
Manufacturing Systems ◽  
Resource Constraints ◽  
Operations Planning ◽  
Complex Products ◽  
Parallel Processes ◽  
Production Order ◽  
Alternative Routes ◽  
Selection Of ◽  
General Method

The searching state space in scheduling of real manufacturing systems with discrete and multi-assortment production is discussed in this paper. The production load is represented by a directed and/or graph called “the aggregated graph of operations planning of the set of orders”. It determines the order of operations, according to which they will be inserted into a schedule. This order must always comply with all assumed precedence and resource constraints and also with given scheduling strategy of a production order. In the elaborated representation the complex products structures and alternative routes of their realization are also considered. The most important issues related to searching this space are discussed in this paper. These include: a general method for searching the graph, sequencing of parallel processes and operations using schedule generation schemes and selection of routes variants.

The Graph of Operations Planning Sequence of a Production Order for Scheduling with Mixed Planning Strategies and Alternatives

2015 ◽  
Vol 809-810 ◽  
pp. 1420-1425
Author(s):  
Krzysztof Kalinowski ◽  
Cezary Grabowik ◽  
Grzegorz Ćwikła ◽  
Witold Janik
Keyword(s):  
Manufacturing Systems ◽  
Hierarchical Structures ◽  
Graph Representation ◽  
Operations Planning ◽  
Single Structure ◽  
Production Order ◽  
Modelling Problem ◽  
Planning Strategies ◽  
Production Orders ◽  
Alternative Routes

The paper presents the most important issues related to the scheduling of production orders in real manufacturing systems. In the elaborated method an and/or type graph of operations planning sequence of a production order is proposed for modelling the production system load. In a single structure the graph takes into account alternative routes of a production order realisation and the precedence constraints in presence of complex, hierarchical structures of processes. Two modelling ways of that process using the "operation on the edge" or "operation on the node" notation are also presented. In the developed method scheduling strategies, which have a major impact on the order of placing operations in the schedule and handling of production lots are also considered. By a state space graph representation of scheduling problem, using graph theory, it can be possible to analyze the structure and complexity of both the modelling problem and the graph search techniques.

Quantitative Models for Complex Physical Systems

2014 ◽  
Vol 1061-1062 ◽  
pp. 1144-1147
Author(s):  
Jun Fu ◽  
Jin Zhao Wu ◽  
Ning Zhou ◽  
Hong Yan Tan
Keyword(s):  
Quantitative Analysis ◽  
State Space ◽  
Control Systems ◽  
Chemical Reaction ◽  
Metric Space ◽  
Manufacturing Systems ◽  
Quantitative Model ◽  
Hybrid Automata ◽  
Physical Systems ◽  
The Difference

We present a quantitative model, called metric hybrid automata, for quantifying the behaviors of complex physical systems, such as chemical reaction control systems, manufacturing systems etc. Due to the introduction of a metric, the state space of hybrid automata forms a metric space, in which the difference of states can be quantified. Furthermore, in order to reveal the distance of system behaviors, we construct the simulation distance and the bisimulation distance, which quantify the similarity of system behaviors. Our model provides the basis for quantitative analysis for those complex physical systems.

General Method for Optimizing Composite Patch Repairs

2015 ◽  
Vol 1120-1121 ◽  
pp. 670-674
Author(s):  
Abdelmadjid Ait Yala ◽  
Abderrahmanne Akkouche
Keyword(s):  
Mechanical Properties ◽  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Optimization Problem ◽  
Composite Patch ◽  
Matlab Program ◽  
Patch Repairs ◽  
Selection Of ◽  
General Method

The aim of this work is to define a general method for the optimization of composite patch repairing. Fracture mechanics theory shows that the stress intensity factor tends towards an asymptotic limit K∞.This limit is given by Rose’s formula and is a function of the thicknesses and mechanical properties of the cracked plate, the composite patch and the adhesive. The proposed approach consists in considering this limit as an objective function that needs to be minimized. In deed lowering this asymptote will reduce the values of the stress intensity factor hence optimize the repair. However to be effective this robust design must satisfy the stiffness ratio criteria. The resolution of this double objective optimization problem with Matlab program allowed us determine the appropriate geometric and mechanical properties that allow the optimum design; that is the selection of the adhesive, the patch and their respective thicknesses.

Intelligente Arbeitsvorbereitung in der Cloud/Smarter operations planning and scheduling in the cloud - Cloud application reduces setup and non-productive times by the use of virtual machine tools

2016 ◽  
Vol 106 (01-02) ◽  
pp. 77-82
Author(s):  
G. Rehage ◽  
F. Isenberg ◽  
R. Reisch ◽  
J. Weber ◽  
B. Jurke ◽  
...  
Keyword(s):  
Virtual Machine ◽  
Machine Tools ◽  
Distributed Simulation ◽  
Cloud Service ◽  
Planning And Scheduling ◽  
Operations Planning ◽  
Manufacturing Operations ◽  
Cloud Application ◽  
Cognitive Information ◽  
Selection Of

Auf dem Weg zu Industrie 4.0 wird die Arbeitsvorbereitung zunehmend von kognitiver Informationstechnik unterstützt. Der Beitrag präsentiert die bisherigen Ergebnisse des Forschungsprojekts „Intelligente Arbeitsvorbereitung auf Basis virtueller Werkzeugmaschinen“. Projektziel ist eine Cloud-Dienstleistungsplattform zur Reduzierung der Rüst- und Nebenzeiten durch eine intelligente Planung. Hierzu zählen unter anderem die Auswahl und Validierung alternativer Maschinen sowie die automatische Optimierung der Einrichtungsparameter durch verteilte Simulationen.   On the way to industry 4.0, the operations planning and scheduling will be aided by cognitive information systems. This contribution presents the previous findings of a research project called “Smart operations planning and scheduling on the basis of virtual machine tools” (translated from German). The aim of the project is the development of a cloud service for the smart planning of manufacturing operations; that will reduce the setup and non-productive times of machine tools. This is achieved by the automatic selection of alternative CNC machines, as well as the optimization of setup parameters via distributed simulation.

Basis für den industriellen 3D-Druck in Stahl/Basics for industrial 3D printing for steel - Contribution to additive manufacturing of complex products in multi-variant and functional skeleton construction

2017 ◽  
Vol 107 (06) ◽  
pp. 415-419
Author(s):  
M. Hillebrecht ◽  
V. Uhlenwinkel ◽  
A. von Hehl ◽  
H. Zapf ◽  
B. Schob
Keyword(s):  
Additive Manufacturing ◽  
Functional Integration ◽  
Complex Geometries ◽  
Layer By Layer ◽  
Laser Additive Manufacturing ◽  
Complex Products ◽  
Metal Parts ◽  
Laser Joining ◽  
Automation Technology ◽  
Selection Of

Mithilfe laserbasierter generativer Fertigungsverfahren (Laser Additive Manufacturing – LAM) ist es möglich, potentiell komplexe Bauteilgeometrien variantenreich herzustellen. Damit kann Gewicht eingespart werden und Funktionen sind integrierbar. In Kombination mit Automatisierungs- und innovativer Lasertechnik in der Schweiß- und Schneidapplikation lässt sich dieser Prozess wirtschaftlich nutzen. Durch pulverbettbasierte Lasergenerierverfahren können metallische Bauteile schichtweise aufgebaut werden, jedoch ist die Auswahl der Werkstoffe limitiert. Im Forschungsprojekt StaVari (Additive Fertigungsprozesse für komplexe Produkte in variantenreicher und hochfunktionaler Stahlbauweisen) vereinen sich die neuesten Erkenntnisse in Material-, Laser-, Füge- und Automatisierungstechnik, um modernen Anforderungen der Automobilbranche in der Massenfertigung sowie bei der Medizintechnik in der Kleinserie gerecht zu werden.   Laser Additive Manufacturing LAM has the potential to generate complex geometries. Through this weight reduction, functional integration and multi-variant production is possible. In combination with automation and innovative laser technology applicated in welding and cutting, this process can be used economically. With powderbed based laser additive manufacturing metal parts can be built up layer by layer. However selection of available metals is limited. In the project StaVari latest findings in material-, laser-, joining and automation technology are joint by qualified partners to meet modern automotive demands in mass production and medicine technology for small batch series.

scholarly journals An Exactly Solved Model for Mutation, Recombination and Selection

2003 ◽  
Vol 55 (1) ◽  
pp. 3-41 ◽  
Author(s):  
Michael Baake ◽  
Ellen Baake
Keyword(s):  
State Space ◽  
Continuous Time ◽  
Sufficient Criterion ◽  
Linkage Disequilibria ◽  
Additive Type ◽  
Mean Fitness ◽  
The Mean ◽  
Necessary And Sufficient ◽  
Independent Mutation ◽  
Selection Of

AbstractIt is well known that rather generalmutation-recombination models can be solved algorithmically (though not in closed form) by means of Haldane linearization. The price to be paid is that one has to work with a multiple tensor product of the state space one started from.Here, we present a relevant subclass of such models, in continuous time, with independent mutation events at the sites, and crossover events between them. It admits a closed solution of the corresponding differential equation on the basis of the original state space, and also closed expressions for the linkage disequilibria, derived by means of Möbius inversion. As an extra benefit, the approach can be extended to a model with selection of additive type across sites. We also derive a necessary and sufficient criterion for the mean fitness to be a Lyapunov function and determine the asymptotic behaviour of the solutions.

scholarly journals Should I Stay or Should I Go? Assessing Intermodal and Synchromodal Resilience from a Decentralized Perspective

2019 ◽  
Vol 11 (6) ◽  
pp. 1765 ◽  
Author(s):  
Tomas Ambra ◽  
An Caris ◽  
Cathy Macharis
Keyword(s):  
Transport Processes ◽  
Analytical Models ◽  
Negative Effects ◽  
Parallel Processes ◽  
Delivery Performance ◽  
Operational Level ◽  
New Thinking ◽  
Truck Transport ◽  
Selection Of

Synchromodal transport incorporates real-time events in a dynamic manner in order to facilitate the most suitable selection of modes, routes and handling points. Up until now, current assessments rely on analytical models. Most of these models average distances for barges and trains via route mapping platforms that provide realistic distances for road only. To reflect on real-world developments more accurately, new thinking and modelling approaches are necessary to bridge academic models with physical transport processes. This paper introduces a computational model which computes movements of agents in geographically referenced space. The model captures stochastic parallel processes for each mode, and simulates decentralized delivery performance of each order in terms of cost, time and emissions at an operational level. Furthermore, we study the routing of individual orders and their responsiveness to disruptions. Computational experiments are performed within a case study which concerns imports of retail goods by unimodal truck transport from France to Belgium. Our findings show that dynamic synchromodal solutions cope with disturbances better, but unnecessary deviations and pro-activeness can also lead to negative effects when compared to static intermodal solutions

Assessment and improvement of competitiveness of industrial complex

2020 ◽  
Vol 30 (5) ◽  
pp. 611-633
Author(s):  
Vadim Krivorotov ◽  
Alexey Kalina ◽  
Vasiliy Tretyakov ◽  
Sergey Yerypalov ◽  
Anna Oykher
Keyword(s):  
Resource Constraints ◽  
Electrical Equipment ◽  
Optimal Portfolio ◽  
Development Projects ◽  
Industrial Complex ◽  
Project Portfolio ◽  
Content Type ◽  
Methodical Approach ◽  
The Impact ◽  
Selection Of

Purpose The purpose of this study is to develop a model for the selection of optimal development projects for an industrial complex (IC), aimed at improving its competitiveness. Design/methodology/approach Selection of optimal projects for IC development is carried out within the framework of a methodical approach to assessing and forecasting the competitiveness of IC based on the phased implementation of the following steps: assessment of the current level of competitiveness of an IC; optimization of the project portfolio aimed at improving the IC competitiveness; forecasting the IC competitiveness. The methodology for assessing the IC competitiveness is based on a comparative analysis of its activities against those of its leading competitors and evaluates two integral characteristics, namely, the level of current competitiveness and the indicator of the competitive potential. The methodical approach to the selection of the optimal portfolio of projects for the development of competitiveness is based on a step-by-step optimization of the portfolio using a dynamic programming procedure, which takes into account the implementation conditions of the projects, resource constraints and the prioritization of these projects. The targeted benchmark for the optimization is an integral indicator of IC competitiveness, comprising various aspects of its activities. Findings Method for multi-factor evaluation of IC competitiveness and the impact of a set of factors driving competitive advantage; set of benchmarks of IC competitiveness; the model for the selection and step-by-step optimization of the portfolio of IC development projects, aimed at increasing competitiveness in the context of resource constraints. Practical implications Methodology described in this paper was used to assess the competitiveness and optimize the project portfolio of Uralelektrotyazhmash Group of Enterprises (UETM), one of the largest power engineering complexes in Russia. The assessment was carried out in comparison with the leading domestic and global manufacturers of electrical equipment, which form UETM’s primary competition in the marketplace. Originality/value The study establishes a method for the comprehensive assessment of IC competitiveness based on the comparison of IC activity indicators with those of leading competitors. The proposed method defines an integral competitiveness index to allow for the quantitative assessment of IC competitiveness, development of measures to improve IC competitiveness and producing a methodology to forecast the impact of such measures; the study proposes a methodical approach to selecting the optimal portfolio of projects for the development of IC based on the stepwise optimization of such a portfolio while taking into account the conditions of their implementation, resource constraints and the impact on the indicator of competitiveness. This approach allows the IC to prioritize the implementation of the development projects and maximize its competitiveness in the context of available resources.

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