Paulo Jorge de Figueiredo Martins

Distributed production planning and control agent-based system

A model of an Agent-based Production Planning and Control (PPC) system that can be dynamically adaptable to local and distributed utilization of production resources and materials is presented. The PPC system is based on the selection of resources to deal with one order of different quantities of one product each time. In this way, one scheduling solution is provided for that particular order. The production resources are selected and scheduled using a multi-agent system supported by an implementation of the Smith Contract Net, using Java Spaces technology. The multi-agent system is based on three main agents: Client, Resource, and Manager. These agents negotiate the final product, and the correspondent components, requested by the client. An order for each product (component) triggers a process of dynamic design of a production system to fulfil that particular order. This system exists until the end of the order.

Rapidly Progressive Encephalopathy: Initial Diagnosis of Creutzfeldt Jakob Disease in an Intensive Care Unit

Creutzfeldt-Jakob disease (CJD) is a rare, incurable and fatal condition that can only be confirmed through neuropathological investigation, such as brain biopsy or post-mortem study. However, a probable diagnosis can be made using clinical criteria. CJD manifests as rapidly progressive dementia with myoclonus and to a lesser extent visual impairment and cerebellar and pyramidal/extrapyramidal signs. We report the case of a previously independent adult male that met all the clinical criteria. Taken together, the investigation results suggested probable CJD. LEARNING POINTS Creutzfeldt-Jakob disease (CJD) is a rare cause of dementia. The rapidly progressive neurological signs and symptoms suggest the diagnosis. Mortality rates are very high even with surgical treatment in these complex patients.

Simulation and economic analysis of an AGV system as a mean of transport of warehouse waste in an automotive OEM

Companies with high quality production systems like the automotive industry OEMs (Original Equipment Manufacturer), need to control the containers in which the raw materials are delivered onto the production lines to make sure quality standards are not breached. They commonly have to change the containers from their suppliers to special clean vessels. Hence a new flow of residues is created by this repacking process, the problem arises with the need to minimize the impact that this flow has on the milk runs that supply the lines with raw materials and maintaining the cost of its operation as low as possible. Different AGV (Automated Guided Vehicles) system configurations were tested based on their financial and functionality feasibility to see if the use of AGVs is viable to perform this kind of activities. SIMIO simulation tool was used to assess the performance of each AGV configuration on the metrics of buffer size, total travelled distances, resource utilization and effect on the output of the plant for four different production levels (units/shift). A configuration was clearly better, for the highest production level scenario: it freed 12 m2 of buffer area; it reduced operators travelled distances by 88%; it was suitable for 120% of the current production levels; had a payback time of less than 2 years and a net present value of 232K€.

Formal grammars for product data management on distributed manufacturing systems

This work shows how formal grammars with attributes can be advantageously used to deal with two fundamental aspects of product data management - product diversity management and generation of specific product data based on clients’ specification – in the context of distributed manufacturing systems, while networks of geographically distant collaborative entities. This contribution will constitute a new component for an existing model, developed by the authors, for dynamic production planning and control which includes the interoperability with industrial equipment. The proposed approach is centered on attributed formal grammars, allowing the formalization of the data representation for each family of products and also of some of the inherent processing (e.g. generation of specific products’ bill-of-materials).