9,633 research outputs found

    A diagrammatic representation for entities and mereotopological relations in ontologies

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    In the graphical representation of ontologies, it is customary to use graph theory as the representational background. We claim here that the standard graph-based approach has a number of limitations. We focus here on a problem in the graph-based representation of ontologies in complex domains such as biomedical, engineering and manufacturing: lack of mereotopological representation. Based on such limitation, we proposed a diagrammatic way to represent an entity’s structure and various forms of mereotopological relationships between the entities

    Broad Histogram Method for Continuous Systems: the XY-Model

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    We propose a way of implementing the Broad Histogram Monte Carlo method to systems with continuous degrees of freedom, and we apply these ideas to investigate the three-dimensional XY-model with periodic boundary conditions. We have found an excellent agreement between our method and traditional Metropolis results for the energy, the magnetization, the specific heat and the magnetic susceptibility on a very large temperature range. For the calculation of these quantities in the temperature range 0.7<T<4.7 our method took less CPU time than the Metropolis simulations for 16 temperature points in that temperature range. Furthermore, it calculates the whole temperature range 1.2<T<4.7 using only 2.2 times more computer effort than the Histogram Monte Carlo method for the range 2.1<T<2.2. Our way of treatment is general, it can also be applied to other systems with continuous degrees of freedom.Comment: 23 pages, 10 Postscript figures, to be published in Int. J. Mod. Phys.

    Content validation and inter-rater reliability of a protocol for the precision assessment of boccia players

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    Purpose: To verify a protocol's content validation and reliability for assessing the precision in the throw of Paralympic boccia in two different steps. Methods: The study was divided into two steps: In step 1, the perception of 15 boccia coaches was evaluated using a questionnaire containing 6 questions about the pertinence of the protocol on a Likert scale (1 to 5). In step 2, reliability was evaluated by two researchers, applying the protocol with two targets (0.5 and 1.0, targets) to verify the short precision (SP), average precision (AP), long precision (LP), and total precision (TP) of 23 boccia athletes (BC1 = 5; BC2 = 7; BC3 = 1; BC4 = 10) in tournaments of the modality. The Content Validity Index (CVI) calculation was applied for the electronic questionnaire, the Intraclass Correlation Coefficient (ICC) for the agreement between evaluators, and the T-Test for the difference between means. p < .05 was adopted. Results: In the result of the CVI, reliability was noticed through the experts' evaluation (Question1 = 1.0; Q2 = 0.93; Q3 = 0.80; Q4 = 0.80; Q5 = 0.93; Q6 = 0.93). There was an agreement between the evaluators by the ICC in the 0.5 targets for SP (p < .01), AP (p < .01), LP (p < .01), and TP (p < .01), and in the 1.0 target for SP (p < .01), AP (p < .01), LP (p < .01), and TP (p < .01). No differences were found between the means in the t-test. Conclusion: It was demonstrated that the protocol meets the established reliability and content validity criteria, allowing its practical use to evaluate the precision in the boccia

    Mitigation of the negative effects of recycled aggregate water absorption in concrete technology

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    The widespread use of natural aggregates in construction activities, together with the global population increase, gave rise to a depletion of this natural resource and to progressive increase of its transport distances. On the other hand, the construction and demolition wastes (C&DW) resulting from the construction activities are often deposited in landfills and city outskirts, causing environmental and social problems, such as erosion, deforestation, water contamination and human conflicts. The reuse of C&DW in concrete preparation would be a good solution for both problems. Recycled aggregates show, however, high water absorption due to porosity. At saturation, water flows from the inside to the engaging cement paste matrix and at dryness the opposite process occurs. This water flow breaks the aggregate-cement paste bonds and increases the W/C ratio in the interfacial transition zone, this degrades the fresh and hardened concrete properties. In this work a staged mixing method based on the aggregate water absorption over time was developed. A staged mixing procedure was optimized to regulate the water flow and manufacture concrete, using recycled aggregates, with levels of workability, strength and shrinkage equivalent to those of conventional concrete. The physical, mechanical and geometrical properties of the aggregates were related to the properties of concrete in its fresh and hardened state. Three types of commercial recycled aggregates were evaluated. Two types of natural aggregates were also studied for comparison purposes. (C) 2016 Elsevier Ltd. All rights reserved.European Regional Development Fund, via Algarve Operational Program [REN 30307 Multi-valor

    International Open Innovation Strategies of Firms in European Peripheral Regions

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    The involvement of companies in different open innovation activities, through knowledge outputs and inputs, has become increasingly important for the success of companies. However, the existing literature on open innovation is scarce concerning the internationalization process of companies. The internationalization of companies is fundamental in the continuous search to increase the performance of companies externally. The objective of the present research is to explain the strategic processes in the internationalization of companies located in peripheral regions at the time of the COVID-19 pandemic from the perspective of dynamic capabilities. The sample used for this research is composed of seven Portuguese companies. The methodology of qualitative nature is exploratory and uses a case study approach. Regarding the foremost modes of operation in international markets and strategies, we find that (1) companies have partnerships with local distributors or appoint exclusive importers/distributors, and (2) companies prefer to place their products in the market through their brand, “co-branded” projects with retailers, or “private label” projects. Of the seven companies under study, six use a standardization strategy, and one opts for a configuration-coordination strategy. Our findings clarified the literature on export and internationalization strategies in a peripheral country, allowing a closer incept of the organizational and dynamic capabilities and an overview of the supporting tools these companies have to compete in the global market. Our study is original because few articles study the internationalization strategies of companies at the time of the COVID-19 pandemic and in peripheral regions of Europe.info:eu-repo/semantics/publishedVersio

    Systematic evaluation of software product line architectures

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    The architecture of a software product line is one of its most important artifacts as it represents an abstraction of the products that can be generated. It is crucial to evaluate the quality attributes of a product line architecture in order to: increase the productivity of the product line process and the quality of the products; provide a means to understand the potential behavior of the products and, consequently, decrease their time to market; and, improve the handling of the product line variability. The evaluation of product line architecture can serve as a basis to analyze the managerial and economical values of a product line for software managers and architects. Most of the current research on the evaluation of product line architecture does not take into account metrics directly obtained from UML models and their variabilities; the metrics used instead are difficult to be applied in general and to be used for quantitative analysis. This paper presents a Systematic Evaluation Method for UML-based Software Product Line Architecture, the SystEM-PLA. SystEM-PLA differs from current research as it provides stakeholders with a means to: (i) estimate and analyze potential products; (ii) use predefined basic UML-based metrics to compose quality attribute metrics; (iii) perform feasibility and trade-off analysis of a product line architecture with respect to its quality attributes; and, (iv) make the evaluation of product line architecture more flexible. An example using the SEI’s Arcade Game Maker (AGM) product line is presented as a proof of concept, illustrating SystEM-PLA activities. Metrics for complexity and extensibility quality attributes are defined and used to perform a trade-off analysis

    Modeling and simulating a textile production system

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    This paper presents a study for a production scheduling problem in a textile company, specifically in the weaving preparation area. Basically, the processing orders can be considered as sequential working steps trough three operations (charging - weaving - discharging), and the goal is to minimize time variation and to avoid delays. The machine utilization should be as higher as possible due to short delivering deadlines. The production unit has got 4 of these weaving machines functioning at the same time. Four dispatching rules were tested in order to find the best solution. The optimization procedure highlighted some interesting issues that are discussed in this paper
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