Multi Domain Design: Integration and Reuse

Design of mechatronic systems is becoming increasingly complex. Companies must continuously reduce time-to-market while increasing the quality, diversity, and functionality of their products. As a result, more and more specialists from various domains are needed to develop such products. To reduce time-to-market, many companies look to reducing the time it takes to design a product. Many focus on the reuse of design objects, leading to libraries of templates and standard components to speed up their design process. However, these reusable design objects are developed and maintained in the specialists’ domains, resulting in communication and integration issues between these domains. This paper discusses these issues and proposes a combined approach for model reuse, design integration, and communication between the designers, design tools, and models involved. A case study at a multi-national company successfully demonstrated that the approach leads to a faster and more consistent design process

Consistency, integration, and reuse in multi-disciplinary design processes

Modern product development becomes an increasingly difficult and complex activity. Issues in such product development can best be managed during the design process. \ud An analysis of issues will show that guarding consistency, facilitating integration, and reusing design information, are good ways to manage the design process. \ud \ud The approach in this research resulted in the Architecture Modeling Framework, which integrates many modeling concepts and methods into a single framework. \ud This framework provides a common machine-readable Architecture Modeling Language that can describe both the system architecture and information flows in the design process. \ud Also described are automation mechanisms for this common language in various design tools and a diagram editor. \ud \ud The Architecture Models themselves define multiple views and mappings, from the function and system decomposition and requirements to the various aspects and domain. They can model the design process in terms of shared parameters, the interfaces between design aspects, and their relation to requirements and functionality, and define the required input/output parameters of design tasks and external models, and connect these to the architectural context

Análisis del caos en series temporales financieras vía el estudio de atractores

[spa] La tesis consiste en la proposición de una metodología para la búsqueda de caos vía el análisis de atractores, con el objetivo de determinar si diversas series financieras presentan comportamientos caóticos. El estudio se realiza mediante la aplicación de algoritmos que testan las propiedades del caos en series temporales. La teoría del caos permite atribuir reglas deterministas a fenómenos aparentemente aleatorios. Gracias al determinismo inherente a los sistemas caóticos es posible, dentro de un cierto rango, hacer predicciones sobre su comportamiento a corto plazo. Sin embargo, esta predictibilidad desaparece a medio y largo plazo, dado que una de las características principales de los sistemas caóticos es su sensibilidad a las condiciones iniciales, por la cual una pequeña modificación de estas condiciones produce importantes cambios en el sistema con el paso del tiempo. De lo anterior se deriva la importancia que tiene la búsqueda de caos en los mercados financieros, ya que el paso de una concepción de mercado aleatoria a una caótica justificaría el uso de técnicas de previsión a corto plazo. Un sistema caótico se caracteriza por tener órbitas densas, ser topológicamente transitivo y ser sensible a las condiciones iniciales. Las dos primeras características implican la presencia de un atractor, esto es, una zona del espacio hacia la que tienden las trayectorias del sistema. Por su parte, la sensibilidad a las condiciones iniciales hace que las trayectorias se muevan de un modo impredecible a medio y a largo plazo dentro del atractor, y que este pueda calificarse de caótico. Así, dado que un sistema se considera caótico si presenta un atractor caótico, en la tesis se estudia el sistema financiero desde una perspectiva caótica, y para ello se propone una metodología que pretende analizar la presencia de este tipo de atractor en series temporales, y que consiste en la aplicación de algoritmos que testan las características de los sistemas caóticos. Para detectar la presencia de órbitas densas el algoritmo propuesto se basa en el “test de diferencias cercanas”. La transitividad topológica se analiza a través de un algoritmo propio. Por último, el algoritmo usado para testar la sensibilidad a las condiciones iniciales se basa en el estudio de los valores propios de la matriz de cambio de estado.[eng] The purpose of this thesis is to contribute to the chaotic analysis of financial time series, providing a comprehensive methodology based on the characteristics of chaotic systems. Through the application of chaos theory, deterministic rules can be attributed to seemingly random phenomena. The determinism inherent in chaotic systems makes it possible to forecast the short-term behaviour of these systems within a certain range. However, over the longer term, this predictability disappears since one of the main characteristics of chaotic systems is their sensitivity to initial conditions. This sensitivity means that any small alteration to the system’s initial conditions causes significant changes over time. In this lies the importance of searching for chaos in financial markets, because a change from the conceptualisation of a random market to that of a chaotic one would justify the use of forecasting techniques in the short term. The mathematical definition of chaos provides the characteristics that can be used as prerequisites of chaotic behaviour. These are: sensitivity to initial conditions, the presence of dense orbits and topological transitivity. The latter two characteristics imply the presence of an attractor, an area in space towards which the trajectories of the system tend. Sensitivity to initial conditions causes these trajectories to move unpredictably within the attractor and this allows the system to be classified as chaotic. There are various instruments to test sensitivity to initial conditions and the existence of a dense orbit. In relation to the property of topological transitivity, a commonly accepted test for determining whether a system is topologically transitive has not yet been found. This failure constitutes a major limitation in the study of the chaotic dynamics of series of observations, as the lack of such a test prevents one of the properties of chaotic systems from being tested. In this thesis I therefore propose an algorithm to distinguish whether a system is topologically transitive from a series of observations of it, and this constitutes its major contribution

Modeling and Using Product Architectures in Inudstrial Mechatronic Product Development: Experiments and Observations

The goal of this work is to practically determine the role of product architecture models to support communication for improving development practices of complex mechatronic products. This paper contains descriptions, observations, and lessons learned from case studies in which the authors tested a language to represent product architectures during product development in a company, as well as the reasons leading to the use of the specific language/model. The tests include construction of architecture models, direct use of the architecture information, model generation from the architecture model, reuse of architecture model information, clarification of existing documentation, and transition towards model-based product development. The work points out desired characteristics of product architecture models as well as characteristics of the necessary implementation tools and framework