An integrated simulation–optimization study for consolidating production lines in a configure-to-order production environment
This study investigates production lines consolidation in a configure-to-order production environment using simulation and optimization strategies. The current production environment has three separate production lines that will be consolidated into two production lines. Two production line configurations are analyzed: product and process layouts. Product layout has a continuous smooth flow, small work-in-process (WIP), short total production time per unit of product, and reduced material handling requirements. On the contrary, process layout offers more flexibility, allows for higher utilization of machines, and requires higher grades of operators’ skills. A simulation-based comparison of the current and future systems is conducted considering lead time, throughput, utilization, and WIP. A mixed integer programming model that optimizes the transportation cost and waiting time is then formulated based on the selected process layout. Simulation results provide recommendations to improve the system level performance measures and support management decisions. The current transportation schedule is ineffective, and hence a real-time dashboard based on the optimization model is suggested. The dashboard will improve communication and transportation between the two production lines.
A simulation-based work order release mechanism for a flexible manufacturing system
A simulation model and real-time interface module for an operational FMS (flexible manufacturing system) facility were developed to evaluate work order release sequences on a real-time basis. Unlike most simulation studies, the evaluation is based on the transient behavior of the system and not steady-state performance. The time window in which a work order is predicted to be completed is considered in order to determine if a particular work order sequence meets due date requirements set forth by the MRP (materials requirement planning) system. In addition, results of the simulation can be used to schedule the building of fixtures and the loading of raw material. The model was successfully interfaced with the real-time control database so that initial conditions could be determined. This information is essential when looking at the transient behavior. Simulation results provide analysts with information to make improvements in the short-term schedule, resulting in better work order release decisions.<<ETX>>
The Open Mobile Alliance: Delivering Service Enablers for Next-Generation Applications
Apractical overview of OMA specifications and how they enable mobile multimedia services & much more ! The Open Mobile Alliance (OMA) is an industry forum, which develops open specifications to help in the creation of applications and services to be deployed over converged networks. The alliance is the leading industry forum for generating market-driven specifications for interoperable mobile service enablers that facilitate global user adoptions of mobile multimedia services. Members include traditional wireless industry segments, such as mobile operators mobile operators (e.g. AT&T, China Mobile, Orange, Sprint Nextel, T-Mobile, Telefonica, Vodafone), equipment and mobile systems manufacturers (e.g. Alcatel-Lucent, Ericsson, Motorola, Nokia, Philips, Samsung, Siemens, Sony-Ericsson), and Information Technology vendors (e.g. BEA Systems, IBM, Microsoft, Oracle Corporation, Sun Microsystems and NEC). Since its formation in 2002, the OMA has made significant progress in areas such as push-to-talk over cellular, device management, presence and group management, and messaging. The Open Mobile Alliance: Provides a comprehensive overview of the service enablers published by the OMA, tying together all the different piece parts developed by the individual working groups Offers a thorough introduction to the OMA Service Environments (OSE) and the specification process for enabling technologies. Discusses enablers for services such as gaming, IMS, Parlay, mobile broadcast and web services. Contains contributions from all stakeholders in the mobile application value chain. The Open Mobile Alliance Alliance is an invaluable resource for OMA members, product managers, network architects and planners, standards managers, standards engineers and IT professionals. Advanced Students and lecturers on mobile application development and standardization courses will also find this book of interest."The success of OMA is due to its individual members' contributions, and this book is testament to their hard work. The individual members' efforts and the authors of this book are to be congratulated on their magnificent achievements." Mark Cataldo, Senior Advisor, Orange SA, OMA Technical Plenary Chairman