RESQME and Stand-Alone Simulation on a Workstation

RC 16037 (#71232) The Research Queueing Package Modeling Environment (RESQME) provides a graphical environment for constructing and solving extended queueing network models ofmanufacturing systems, for plotting graphs of results and for viewdng animations of models. The modeling environment can be run entirely on a workstation or optionally can execute large simulations on a host system using cooperative processing. In this paper we give a brief introduction to RESQME and to the RESQ modeling elements. We demonstrate how to use the package by constructing a simple model of part of a manufacturing line and solve this model to produce charts of performance measures and an animation which shows how the jobs flow through the system. By having the simulation available for use on the workstation and cooperatively on the host, RESQME provides a unique tool for understanding the performance of manufacturing systems. A user can do most of the model debugging locally on the workstation and make short püot runs to get a feeling for the amount of resources necessary to make more realistic experiments on the • host. Then long runs which investigate large parts ofthe parameter space can be done cooperatively on the host. Whether the model is solved on the workstation or on the hosMhe graphics environment provides the same user interface to all of the underlying files. The processor where the model is solved is transparent to the user. In aU cases, the user has easy access to plots ofresults and to the animation ofthe model diagra

An Introduction to the RESearch Queueing Package for Modeling Computer Systems and Communication Networks

A queueing network is an important tool for modeling systems where performance is principally affected by contention for resources. Such systems include computer systems, communication networks and manufacturing lines. In order to effectively use queuing networks as performance models, appropriate software is necessary for definition ofthe networks to be solved, for solution ofthe networks and for examination of the performance measures obtained. The RESearch Queueing Package (RESQ) and the RESearch Queueing Package Modeling Environment (RESQME) form a system for constructing, solving and analyzing extended queueing network models. We refer to the class of RESQ networks as extended because of characteristics which allow effective representation of system detail. RESQ incorporates a high level language to concisely describe the structure of the model and to specify constraints on the solution. A main feature of the language is the capability to describe models in a hierarchical fashion, allowing an analyst to define submodels to be used analogously to use of macros in programming languages. RESQ also provides a variety of methods for estimating the accuracy of simulation results and for determining simulation run lengths. RESQME is a graphical interface for RESQ. In this introduction, we limit our examples to computer systems and communication networks. Acknowledgement: The authors wish to thank their co-developers of RESQME: Jim Kurose and Kurt Gordon. We also want to thank Ben Antanaitis, Howard Jachter, Jack Servier, Daniel Souday and Peter Welch for their many suggestions which helped improve the RESQME package and Anil Aggarwal, Al Blum, Gary Burkland, Rocky Chang, Janet Chen, Diana Coles, Prakash Deka, Paul Lnewner, and Geoff Parker for their work in implementing RESQME. We would also like to thank our users for their ideas and feedback that we tried to incorporate in RESQ and RESQME. We remain indebted to Charlie Sauer for his design, guidance, inspiration, and development ofthe RESQ languag

Higher Level Modeling in RESQME

RC 13554 (#60544) The RESearch Queueing Package Modeling Environment (RESQME) is a graphical workstation environment for iteratively constructing, running and analyzing models of resource contention systems. It is built on top of the RESearch Queueing Package (RESQ) which provides the functionality to evaluate extended queueing networks. In this paper we describe the high-level building component design for RESQME. The modeler is provided with tools to create his own icons and to associate them with submodels. He then uses ilicsc building blocks to construct his model. This capability extends the funtlaiiicnlal building blocks of RESQ and allows the user to create models with objccls directly related to his application domain

Rule-Based Run Control and Evaluation for Simulation

RC 19494 (84719) Modeling projects are often faced with a large parameter space that has to be explored in order to produce a set of performance measures representing the behavior of the systems under study. In this paper, we describe a software component that provides the analyst with the functionality to specify a design of experiments and execute a search algorithm over the resulting parameter space. The component invokes the associated simulation runs and compares the results to a goal to determine the solution. This component has been implemented as the run control mechanism in the RESearch Queueing Modeling Environment (RESQME). We demonstrate the use of this experimental run control and evaluation component for simple enumeration of the parameter space, interactive evaluation, as well as generalized rule-based control

Two-layer on-line parameter estimation for adaptive incremental backstepping flight control for a transport aircraft in uncertain conditions

Presence of uncertainties caused by unforeseen malfunctions of the actuator or changes in aircraft behavior could lead to aircraft loss of control during flight. The paper presents two-layer parameter estimation procedure augmenting Incremental Backstepping (IBKS) control algorithm designed for a large transport aircraft. IBKS uses angular accelerations and current control deflections to reduce the dependency on the aircraft model. However, it requires knowledge of the control effectiveness. The proposed identification technique is capable to detect possible problems such as a failure or presence of unknown actuator dynamics even in case of redundancy of control actuation. At the first layer, the system performs monitoring of possible failures. If a problem in one of the control direction is detected the algorithm initiates the second-layer identification determining the individual effectiveness of the each control surface involved in this control direction. Analysis revealed a high robustness of the IBKS to actuator failures. However, in severe conditions with a combination of multiple failures and presence of unmodelled actuator dynamics IBKS could lost stability. Meanwhile, proposed control derivative estimation procedure augmenting the IBKS control helps to sustain stability

Bit Bang 9: Entrepreneurship

This book is the 9th in the Bit Bang series of books produced as multidisciplinary teamwork exercises by doctoral students participating in the course Bit Bang 9: Entrepreneurship at Aalto University during the academic year 2016–2017. Working in teams, the students set out to answer questions related to entrepreneurship and to brainstorm radical scenarios of what the future could hold. This joint publication contains articles produced as teamwork assignments for the course

Transformations on hypergraph families

We present a new general theory of function-based hypergraph transformations on finite families of finite hypergraphs. A function-based hypergraph transformation formalises the action of structurally modifying hypergraphs from a family in a consistent manner. The mathematical form of the transformations facilitates their analysis and incorporation into larger mathematical structures, and concurs with the function-based nature of modelling in the physical world. Since quotients of hypergraphs afford their simplification and comparison, we also discuss the notion of a quotient hypergraph transformation induced by an equivalence relation on the vertex set of a hypergraph family. Finally, we demonstrate function-based hypergraph transformations with two fundamental classes of examples involving the addition or deletion of hyperedges or hypergraphs

Simulação aplicada a manufatura flexivel

Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro TecnologicoOs sistemas flexíveis de manufatura resultam do desejo de alcançar a produtividade da produção de massa com a agilidade da fabricação por encomenda. Em virtude do grau de automação, da flexibilidade, do número elevado de diferentes produtos fabricados em pequenos lotes, estes sistemas apresentam uma complexidade maior do que os tradicionais. A obtenção da eficiência produtiva destes sistemas envolve otimizar um grande número de variáveis decisórias e solucionar uma problemática variada que vai de problemas de longo prazo, como os de projeto, médio prazo, representado pelo planejamento, curto prazo, identificado pelos problemas de programação e, ainda, por problemas de curtíssimo prazo, relacionados com o controle em tempo-real do sistema. A complexidade destes sistemas fez da simulação senão a única ferramenta para sua análise, pelo menos, a mais importante. Com o barateamento dos custos de hardware e a crescente aceitação da simulação como técnica da solução de problemas, o número de recursos de software relacionados aos SFM cresceu muito além do que qualquer um seria capaz de acompanhar. O propósito deste trabalho é descrever estes sistemas, sua origem, vantagens e problemática, classificando e analisando os instrumentos de software disponíveis possibilitando, desta forma, decisões melhores e mais rápidas por parte de quem pretenda faser uso da simulação para estudá-los