SpringBoard: game-agnostic tool for scenario editing with meta-programming support

Although we have recently seen an increase of good, free game engine editors, general purpose scenario (level) editors are still lagging behind in terms of functionalities and ease of use. Using them to create game scenarios can be difficult as they often expose general engine capabilities instead of limiting the toolset to fit game-specific requirements. They often require programming skills to use, which introduce additional user skill requirements, and configuring them for a specific game can be equally difficult. In this paper we have developed SpringBoard, an open source scenario editor for games using the SpringRTS engine. Extending it to support game and level requirements is achieved with multi-level meta-programming, while still providing a system that is integrated with the GUI editor and therefore intuitive to use. Our meta-programming system has support for trigger elements (events, functions and actions), custom (composite) data types, scoped data access, higher order functions and actions, and data synchronization mechanics. This novel approach allows us to have the full expressiveness of the underlying programming language, while exposing a user-friendly GUI that consists of terminology familiar to the domain expert.     

Orthotropic material orientation optimization method in composite laminates

This paper proposes a optimization method that is capable of simultaneous design of multiple layers in a composite laminate with respect to multiple objective functions. The optimization process obtains a continuous orientation of an orthotropic material for each layer of the laminate. Each layer by itself is a single design domain, which allows multiple domains to be stacked in various orientations. Multiple optimization objectives are considered resulting in layers that perform different functions. The layers are modeled within a three-dimensional structure and by discretizing the structure using three-dimensional elements, the interaction between individual layers can be modeled. This also allows the optimization method to obtain a three-dimensional orientation vector. In this study, the individual layers are assumed to be thin, limiting the orientation vector to the mid-plane of the layer. The optimization model is tested on a two-layer laminate in which one layer is optimized for thermal control by directing heat toward specified sections while shielding other sections and the second layer is optimized to reduce the total deformation of the laminate structure that results from the thermal load. The results of simultaneous optimization for both layers are shown for several different configurations of boundary conditions.     

A Crystalline Si3N4/Amorphous Si3N4 Composite

A composite consisting of elongated α-Si₃N₄ crystallites (5–50 (Am in diameter) embedded in an amorphous Si₃N₄ matrix was synthesized by chemical vapor deposition. The hardness and indentation fracture toughness of the amorphous matrix and of the composite have been evaluated at temperatures from ambient to 1200°C. It was found that the crystallites have relatively little influence on the hardness and indentation fracture toughness when the surrounding matrix is amorphous. However, a 1400°C heat treatment of the material results in a matrix consisting of small crystals (100 nm in diameter) surrounded by carbon-containing regions which appear to be amorphous in the TEM; TEM and EELS in nearby triple points revealed the presence of amorphous carbon. After heat treatment, the indentation fracture toughness at ambient and at 1200°C is increased due to extensive microcracking. The Vickers hardness at 1200°C also increased significantly as a result of the heat treatment. The relationship between the mechanical properties and the microstructure is discussed.     

Increasing the capacity of terminal for bulk cargo unloading

Work of the ports (terminals) with its optimal capacity assumes prompt accommodation of vessels with minimal waiting time in the port and with maximal use of berth facilities, i.e. bigger unloading capacity. The way, how capacity of the river terminals for bulk cargo unloading can be increased, without new capital costs by introducing the strategy in the work of the unloading devices, is presented. Hierarchical structure of the system is connected with phases of servicing and stochastic character of the input/output values is underlined. Simulation model of the terminal work with strategy is developed. This results in shorter time needed for vessel unloading and therefore bigger unloading capacity of the terminal. Some of obtained results are applied and verified on existing system.     

Review of possibilities and necessities for building lifetime commissioning

The article presents review of possibilities and necessities for a practical application of lifetime commissioning in building facilities. The implementation of life-long commissioning of buildings implies energy efficiency, ensures a rational use of energy and thereby decreases CO₂ emissions. Therefore, first the term “commissioning” is explained in the article. Commissioning necessities, which are induced by different operational faults, the new laws driven by idea for decreasing CO₂ emission, and benefits, are explained, too. Besides USA's and European laws for the energy performance of buildings, the Norwegian state of the art in this area is also presented. The difference in terms and methods for fault detection and diagnosis are elaborated in the article. Finally, examples of different commissioning tools are briefly introduced and compared. In order to make building sustainable and encourage energy savings, potential commissioning users are suggested.     

Modified self-propagating high-temperature synthesis of nanosized La0.7Ca0.3MnO3

A modified solid-state combustion route was developed for the preparation of nanocrystalline manganite La_0.7Ca_0.3MnO₃ in a single-step process, using metal nitrates and glucose/KNO₃ redox mixture. The obtained sample was found to crystallize within O′ type of orthorhombic perovskite structure (space group Pnma), without the presence of other structural phases or impurities. Nanoparticles are found to have particle size in the range 12–35 nm, and to be highly crystalline without the presence of amorphous surface layer. Magnetic measurements show that nanoparticles display bulk-like magnetic properties, with ferromagnetic phase transition at 125 K and the absence of superparamagnetic or spin-glass behavior.     

Fuzzy inference mechanism for recognition of contact states in intelligent robotic assembly

This paper presents a methodology for generating a fuzzy inference mechanism (FIM) for recognizing contact states within robotic part mating using active compliant motion. In the part mating process, significant uncertainties are inherently present. As a result it is pertinent that contact states recognition systems operating in such environment be able to make decisions on the contact state currently present in the process, based on data full of uncertainties and imprecision. In such conditions, implementation of fuzzy logic and interval inference brings significant robustness to the system. As a starting point for FIM generation, we use a quasi-static model of the mating force between objects. By applying Discrete Wavelet Transform to the signal generated using this model, we extract qualitative and representative features for classification into contact states. Thus, the obtained patterns are optimally classified using support vector machines (SVM). We exploit the equivalence of SVM and Takagi–Sugeno fuzzy rules based systems for generation of FIM for classification into contact states. In this way, crisp granulation of the feature space obtained using SVM is replaced by optimal fuzzy granulation and robustness of the recognition system is significantly increased. The information machine for contact states recognition that is designed using the given methodology simultaneously uses the advantages of creation of machine based on the process model and the advantages of application of FIM. Unlike the common methods, our approach for creating a knowledge base for the inference machine is neither heuristic, intuitive nor empirical. The proposed methodology was elaborated and experimentally tested using an example of a cylindrical peg in hole as a typical benchmark test.