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In this paper, we propose designing transportation network topology and traffic distribution under fluctuating conditions using a bio-inspired algorithm. The algorithm is inspired by the adaptive behavior observed in an amoeba-like organism, plasmodial slime mold, more formally known as plasmodium of Physarum plycephalum. This organism forms a transportation network to distribute its protoplasm, the fluidic contents of its cell, throughout its large cell body. In this process, the diameter of the transportation tubes adapts to the flux of the protoplasm. The Physarum algorithm, which mimics this adaptive behavior, has been widely applied to complex problems, such as maze solving and designing the topology of railroad grids, under static conditions. However, in most situations, environmental conditions fluctuate; for example, in power grids, the consumption of electric power shows daily, weekly, and annual periodicity depending on the lifestyles or the business needs of the individual consumers. This paper studies the design of network topology and traffic distribution with oscillatory input and output traffic flows. The network topology proposed by the Physarum algorithm is controlled by a parameter of the adaptation process of the tubes. We observe various rich topologies such as complete mesh, partial mesh, Y-shaped, and V-shaped networks depending on this adaptation parameter and evaluate them on the basis of three performance functions: loss, cost, and vulnerability. Our results indicate that consideration of the oscillatory conditions and the phase-lags in the multiple outputs of the network is important: The building and/or maintenance cost of the network can be reduced by introducing the oscillating condition, and when the phase-lag among the outputs is large, the transportation loss can also be reduced. We use stability analysis to reveal how the system exhibits various topologies depending on the parameter. [ABSTRACT FROM AUTHOR]

Background: The current strategies for making electronic devices are generally time, water, material and energy consuming. Here, the direct writing of composite functional circuits through comprehensive use of GaIn10-based liquid metal inks and matching material is proposed and investigated, which is a rather easy going and cost effective electronics fabrication way compared with the conventional approaches. Methods: Owing to its excellent adhesion and electrical properties, the liquid metal ink was demonstrated as a generalist in directly making various basic electronic components such as planar resistor, inductor and capacitor or their combination and thus composing circuits with expected electrical functions. For a precise control of the geometric sizes of the writing, a mask with a designed pattern was employed and demonstrated. Mechanisms for justifying the chemical components of the inks and the magnitudes of the target electronic elements so as to compose various practical circuits were disclosed. Results: Fundamental tests on the electrical components including capacitor and inductor directly written on paper with working time up to 48 h and elevated temperature demonstrated their good stability and potential widespread adaptability especially when used in some high frequency circuits. As the first proof-of-concept experiment, a typical functional oscillating circuit including an integrated chip of 74HC04 with a supply voltage of 5 V, a capacitor of 10 nF and two resistors of 5 kΩ and 1 kΩ respectively was directly composed on paper through integrating specific electrical elements together, which presented an oscillation frequency of 8.8 kHz. Conclusions: The present method significantly extends the roles of the metal ink in recent works serving as only a single electrical conductor or interconnecting wires. It opens the way for directly writing out complex functional circuits or devices on different substrates. Such circuit composition strategy has generalized purpose and can be extended to more areas, even daily pervasive electronics. [ABSTRACT FROM AUTHOR]

As the complexity of automotive vehicles increases, so does the need for high calibre, multi-disciplined engineers. This paper provides a discussion into the type of control systems found in modern automotive vehicles and the skills required by the engineers working in this mechatronic system environment. [ABSTRACT FROM AUTHOR]

Despite a world-wide interest in mechatronics education, there is no clear and consistent understanding of what mechatronics is, nor how, and at what level, it should be taught. The key challenge for mechatronics course designers is seen as that of ensuring an appropriate balance between depth and breadth while providing opportunities to enable students to practise integration. The paper discusses this in relation to a number of mechatronic themes. Factors influencing the design, structure and content of a mechatronics programme are discussed and suggestions made as to the possible core content of such a programme. [ABSTRACT FROM AUTHOR]

Traditional dynamic modelling of multidisciplinary systems involves separate sets of analysis skills for each domain. Bond Graphs embrace commonality, providing a concise unified means of system representation and a systematic analysis method. This paper introduces Bond Graphs, benefits of acausal component models, and software for automated equation generation and simulation. [ABSTRACT FROM AUTHOR]

The paper describes the utility of a low cost, 1 m2 by 2 m forced ventilation, micro-climate test chamber, for the support of research and teaching in mechatronics. Initially developed for the evaluation of a new ventilation rate controller, the fully instrumented chamber now provides numerous learning opportunities and individual projects for both undergraduate and postgraduate research students. [ABSTRACT FROM AUTHOR]

In all branches of engineering, from the earliest times to the present and into the future, there exist only two fundamental approaches to solve problems that arise in the discovery of knowledge and its application to society's needs: a. Theoretical modeling. b. Experimental measurement In engineering, this is true regardless of the discipline (mechanical engineering, electrical engineering , chemical engineering, etc.) or the engineering function (design, manufacturing, etc.). While some problems are adequately treated by using only theory, or only experimentation, most require judiciously chosen mix of these techniques. This is the situation that is presented in this paper, where besides to realize the theoretical analysis of the problem are used experimental measurements to obtain information that allow us to determine the cause of failure in the threaded fasteners of an assembled joint. [ABSTRACT FROM AUTHOR]