Maria Leonilde Rocha Varela

Collaborative Dynamic Decision Making: A Case Study from B2B Supplier Selection

The problem of supplier selection can be easily modeled as a multiple-criteria decision making (MCDM) problem: businesses express their preferences with respect to suppliers, which can then be ranked and selected. This approach has two major pitfalls: first, it does not consider a dynamic scenario, in which suppliers and their ratings are constantly changing; second, it only addressed the problem from the point of view of a single business, and cannot be easily applied when considering more than one business. To overcome these problems, we introduce a method for supplier selection that builds upon the dynamic MCDM framework of [1] and, by means of a linear programming model, can be used in the case of multiple collaborating businesses planning their next batch of orders together.

Experimental Platform for Collaborative Inter and Intra Cellular Fuzzy Scheduling in an Ubiquitous Manufacturing System

The aim of manufacturing scheduling is the efficient allocation of machines and other resources to jobs, or operations within jobs, and the subsequent time phasing of these jobs on individual machines. Therefore, the scheduling of production processes of a distributed cellular manufacturing enterprise is one of the significant tasks to be performed to achieve competitive production, which means, e.g., to deliver products on time or to use resources efficiently and reduce production times. In this paper we propose a Web Platform for solving those kind of problems occurring either in intra or inter cellular manufacturing scenarios. Scheduling methods are local or remotely available through web services and can be easily and continuously incorporated in a distributed repository, which integrates XML-based components, belonging to a range of business partners, integrating a Virtual Enterprise, in the context of an Ubiquitous Manufacturing System. The scheduling data modeling and the data transferring processes are based on XML and related web technologies and decision-making is carried out through an interactive approach relying on fuzzy sets and user friendly interfaces for supporting cellular manufacturing scheduling.

The Tool Supporting Decision Making Process in Area of Job-Shop Scheduling

Today most manufacturing companies from machine building industry are operating in single unit or short-run production which is very complex in terms of decision making processes in production planning area. The difficulty in decision making in the area of scheduling is caused by the necessity of analysing multiple factors and evaluating various scheduling options due to numerous criteria. The article presents the author’s tool supporting decision making in the area of job-shop scheduling. The tool introduced in the article enables scheduling based on author’s priority rule allowing maximum usage of the most loaded resource (known as critical resource), which determines efficiency of the production system. The tool has been designed and verified as a part of PhD dissertation research.

An Ontology For A Model Of Manufacturing Scheduling Problems To Be Solved On The Web

In this paper we describe an ontology for a model of manufacturing scheduling problems to be solved on the web, through several different scheduling methods made available by a web scheduling decision support system. This approach aims enabling to share scheduling knowledge and methods, in a globally distributed context, in order to facilitate solving these problems, either in the industry or in the academic and research context. The proposed ontology is described in terms of basic objects, the scheduling problem attributes, in the form of problems characterization parameters; problem classes or types of scheduling problems and relations among problem classes; and problems instances. Finally, a sample of methods is presented for solving some well known problems arising in the scope of manufacturing scheduling through the web.

Technologies Integration for Distributed Manufacturing Scheduling in a Virtual Enterprise

Distributed scheduling problems are challenging tasks to researchers and practitioners that have been gaining increasing popularity over the years. This is partly attributed to the fact that multi-site production and networked manufacturing environments are increasing as a consequence of globalisation. In this paper a system for technologies integration for supporting distributed scheduling in a Virtual Enterprise, by combining a simulation-based approach, with the Hungarian algorithm, for solving job-shop scheduling problems is presented, in order to show how we can benefit from this combination of procedures for distributed manufacturing scheduling.

A Web-Based Decision Support System for Supply Chain Operations Management Towards an Integrated Framework

Operations management deals with the design and management of products, processes, services and supply chains. Supply chains integration and manufacturing operations management can benefit highly from the use of web-based technologies by ensuring a smooth connectivity and interoperability between software components, especially in a real-time basis by reinforcing the use of multi-agents combined with web service based technologies. The more the accurate and dynamic is the update of the information in a company, the more the enhancement of the manufacturing decision-making process will be over the whole company’s performance. Moreover, web-based technologies combined with multi-agents provide gains in agility and flexibility for building versatile supply chain management systems. Therefore, the purpose of this paper is to present and propose an integrated web-based framework to cover the main integration requirement from a system point of view, this within the main purpose of supporting the supply chain management and operation in supply chain environments. For this purpose, an automotive supply chain industry is considered to illustrate the applicability of this proposed framework.

Collaborative Network Platform for Multi-site Production

The Competition in the global economy is intensifying the implementation of web-based collaboration platforms to improve the personalized interaction between clients and producers. Agility in the order-production-delivery cycle is a key element for industrial enterprises as a means to meet the requirements of this paradigm. Agile/Virtual Enterprise based scenarios are characterized by large product variety dependent on product specific requirements of individual customers. Therefore, to enable an enriched network based tool for Virtual Enterprise specification and configuration, there is a need to define a collaborative environment for dynamically enable candidate business partners to integrate it. In this paper, we propose a web platform and describe its main functionalities for interactive multi-site production network integration.

Shortening changeover time — An industrial study

This paper presents the results of the use of the Single Minute Exchange of Die method to shorten changeover time on machines in a polish production company. This project has been developed for a manufacturing company, whose products are fiberboard, hardboard and softboard products manufactured by a highly specialized industry using only pure wood fibers. Long changeover times used to conduct to bad results in timely delivery of orders. Therefore, in this work each element of the changeover time was analyzed to understand if it could be eliminated, moved or simplified. Implemented solutions significantly reduce setup time and improve the Companys competitiveness.

Distributed Manufacturing Scheduling Based on a Dynamic Multi-criteria Decision Model

Distributed manufacturing scheduling is increasingly necessary in nowadays global manufacturing environments and assumes primal importance to ensure enhanced solutions for such globally distributed manufacturing scheduling problems. In this chapter an approach based on a dynamic multi-criteria decision model is proposed, which enables (re)scheduling strategies and trade-offs between different performance measures. In this dynamically changing environment, real-time changes may occur in production and there is a need for a global view and manufacturing (re)scheduling to improve the globally distributed manufacturing scenario. The approach main aim is to support scheduling decision making, namely through reliable and timely deliveries, as well as improved manufacturing management of available resources. An illustrative example, integrating a set of manufacturing cells is provided to clarify the approach.

Cycle Time Reduction in Deck Roller Assembly Production Unit with Value Stream Mapping Analysis

Cycle time reduction is of paramount importance in a manufacturing industry as the customer not only emphasizes on the quality of the product but also takes into consideration the timely delivery of the product. The proposed framework and the advanced methodology in this paper are capable of dealing with each stage of the considered manufacturing unit by maximizing the value of the product through reduction of cycle times and minimization of waste. The time required for all the processes in the manufacturing of the deck rollers is identified and are classified into value added (VA) and non-value added (NVA). Finally, the cycle times were reduced by applying the lean tools and principles on some managerial relevances. Also, Arena software was used to simulate the current and future value stream maps and the change in the cycle times, waiting times, machine utilization, etc. was determined.