Path planning for active tensegrity structures

This paper presents a path planning method for actuated tensegrity structures with quasi-static motion. The valid configurations for such structures lay on an equilibrium manifold, which is implicitly defined by a set of kinematic and static constraints. The exploration of this manifold is difficult with standard methods due to the lack of a global parameterization. Thus, this paper proposes the use of techniques with roots in differential geometry to define an atlas, i.e., a set of coordinated local parameterizations of the equilibrium manifold. This atlas is exploited to define a rapidly-exploring random tree, which efficiently finds valid paths between configurations. However, these paths are typically long and jerky and, therefore, this paper also introduces a procedure to reduce their control effort. A variety of test cases are presented to empirically evaluate the proposed method. (C) 2015 Elsevier Ltd. All rights reserved.Peer ReviewedPostprint (author's final draft

Identification of Exogenous and Endogenous Factors Affecting Competitiveness: An Application to the Spanish Furniture Industry

In this paper we study what type of exogenous (related to the external structure) and endogenous (related to the firm) aspects affect industry´competitiveness. The framework is used to asses competitiveness of organizations in the Spanish furniture industry. In doing so, we deep in the theoretical concepts related: in one hand, the industrial sinergical concentration and, in the other hand, literature concerned to resources and capabilities. In this way, we apply a conceptual framework developed by the authors in order to identify the critical aspects that can influence competitiveness and, then, describe the results. The applicability of the model is analyzed in the Spanish furniture industry, specifically in the Valencian Community, where is mainly concentred. From the results obtained we are able to conclude that the method is effective in identifying both exogenous and endogenous aspects.

A Methodological Proposal to Evaluate the Sinergical Industry Concentration

This study deals with the firms’ competitiveness in traditional industries. We understand traditional industry as the one that has transmitted its knowledge generation after generation, and it also has some specific characteristics, such as not being a new industry because its activities have been carried out for many years, to have small and medium sized businesses with little or no presence of transnational firms or having little investment on technology and activities of research and development. The objective of this paper is to present a methodological process for the study and evaluation of the impact of the sinérgic geographical concentration of an industry in its competitiveness. The geographical concentration is a factor of great importance, facilitates the exchange and the cooperation among research centers, among the clients and the suppliers of the region, and it promotes research in the industry (Porter, 1998). On the other hand, the specific concentration of activities in a concrete zone attracts the specialized knowledge. The importance of the geographical concentration and the evidence of the existence of industrial clusters has been studied in an extensive manner through time; Saxenian (1996) analyzed the organization and the characteristics of the electronic firms of Sillicon Valley, Glasmeier (1991) the Swiss clocks, Faulkner and Anderson (1987) the film industry in Hollywood, Scott (1991) the electronic-aeroespacial industry in the south of California, and Abrupt (1982) studied the organization of firms in the north of Italy. Following Kaplan (1986), it turns out to be difficult to imagine that theories in the field of management can be verified, if the test is not carried out inside its context. These tests should serve not only to describe the existence or not of procedures, but also to deduce and to contrast how and why certain practices have to be carried out. If the intention of the researcher is to generate a theory, taking into account the theoretical framework and the key questions to answer are how they are created and how they influence the geographical concentration in the competitiveness of an industry, the most appropiate would be to carry out an explanatory type case study. Some cases will be studied according to Rouse and Daellenbach, (1999). The study of cases to be carried out follows the model proposed by Pérez (1998). The method that will be used in this study, interviews in depth, is classified as direct obtaining of data. The type of interview used is the so call interview of open answers (King, 1994). This technique combines the advantages of the use of closed questionnaires along the qualitative interviews. In the paper, we present an instrument to evaluate the impact of the geographical concentration.

Aridisols of Spain

6 Pags.- 2 Tabls.This paper reviews the distribution and classification of Spanish Aridisols and discusses some taxonomic problems and major management practices. Little literature is available about Spanish Aridisols. Most of the information contained in this Daper comes from soil maps and from the authors unpublished data. The discussion covers the update of Soil Taxonomy, the unsuitability of Newhall's method for some Spanish Mediterranean areas, and the taxonomic status of the gypsiferous soils. Many of the soils classified as Aridisols (S.S.S., 1975) are now distributed into several Orders because the EC criterion has been dropped at this hierarchic level. Recently, a new method for soil moisture regime calculation has been developed in Spain. This method improves the delineation of the aridic regions. Micromorphology provides a better knowledge of hypsiferous soils, and two kinds of gypsic horizons have been identified. Apart from marginal uses. the management of Spanish Aridisols is based on water supply and/or water saving and on taking advantage of early cropping. The following conclusions can be made: (i) the new model of soil moisture regime calculations can be applied to the presumed aridic areas of Spain and calibrated with soil moisture measurements in the field, (ii) the inclusion of gypsiferous soils into three Orders disagees with their distinct morphology and behavior, (iii) refinement in the gypsic horizon definition is needed to link microscopic features and field criteria, and (iv) both old and new management practices in Aridisols must be reported in detail for improvement, the adaptation of new technologies, and extension of management practices to new areas.Peer reviewe

The Importance of Local Aspects in Traditional Industries’ Competitiveness: an Overview of the State of the Art

The process of globalization of the economy has modified the productive activity, enlarging the level of rivalry among firms. If it wants to respond with success to this new situation, a high competitiveness level should be maintained. The word is to the order of the day, with an implicit meaning of progress and advance, although it is not easy to find a definition of it. Many authors have tried this theme in depth. As Pérez (2001) indicates, there are four factors that determine the success of a business: the region where it is located, the industry to which it belongs, the cluster, and its own resources. According to other authors, the succes or failure of a business will be determined by the resources, the capacities and the strategies applied. There are many authors that affirm that competitiveness is a very located process, based on aglomerations of firms organized around one or various related industries, that converge. (Porter, 1985, 1998, Grant, 1996b, Mintzberg 1999). Some other affirm that the strategy of the firms must be based on internal resources, having these the main importance upon the market (Grant, 1996b). According to Grant (1996b), it is more advisable for the businesses that they become competitive based on its endogenous factors. The capacity of reaction of a firm requires not only a deep knowledge of the environment, but it also depends on the function of management, and the degree in which the culture of the organization affects the profit of value and the obtention of benefits of the business. Although these two theories, the external one the internal one have been presented like different alternatives for the study of an industry, other authors consider them complementary (Henderson, 2000), since, while the first one focuses its attention on the structure of the industry, the second does it in the fact that the capabilities (abilities, investments, knowledge, etc.) developed by an organization are the ones that build an strong competitive advantage. The study has focused on the macroeconomic focus, distinguishing also the internal and external aspects of it. Some of the most accepted models by the scientific comunity are presented within the external focus. The analysis of the geographical variable as base of a sinergic action of the businesses and of the related agencies established in an specific surroundings, the cluster, has been considered as part and development of the competitive strategy Finally both theries have been opposed and a new theoretical model, based on the adaptation of the main two currents that currently exist, has been proposed.

The Regulation of Labor

We investigate the regulation of labor markets through employment laws, collective bargaining laws, and social security laws in 85 countries. We find that richer countries regulate labor less than poorer countries do, although they have more generous social security systems. The political power of the left is associated with more stringent labor regulations and more generous social security systems. Socialist and French legal origin countries have sharply higher levels of labor regulation than do common law countries, and the inclusion of legal origin wipes out the effect of the political power of the left. Heavier regulation of labor is associated with a larger unofficial economy, lower labor force participation, and higher unemployment, especially of the young. These results are difficult to reconcile with efficiency and political power theories of institutional choice, but are broadly consistent with legal theories, according to which countries have pervasive regulatory styles inherited from the transplantation of legal systems.

A Conceptual Framework for the Industrial District Analysis: from Knowledge to Resources

Traditional literature on Industrial Districts has remarked the social capital as a core key in the development process of a sustainable territorial competitive advantage. In that concept authors are allocated part of the externalities without being underpined by an integrating conceptual framework. Recent resource-base view and knowledge management theory, as well as intellectual capital approach, can all be use as a conceptual framework to allocate all the industrial district’s special features in a more comprehensive and connected arena. We establish a conceptual framework by integrating different approaches and adapt all of them to specific industrial district case. Moreover, we adapt the SECI knowledge management model to the cluster case as a useful way to understand the tacit knowledge dissemination that occurs in the industrial district.

Sistemas de información geográfica y algoritmos de optimización aplicados a problemas geoespaciales en la administración de tierras

[Resumen] La tierra es un factor estratégico de suma importancia en el desarrollo de una determinada región. La tierra ha de ser considerada como un bien capaz de generar crecimiento económico y de la que hay que intentar sacar el máximo provecho. Esta tesis aplica las nuevas tecnologías a procesos de la Administración de Tierras que hasta ahora o bien no se hacían, o bien se hacían de forma rudimentaria. Uno de estos procesos es la ordenación territorial que, por su propia naturaleza, involucra gran cantidad de elementos con información geográfica (parcelas, edificaciones, entorno, ...) con los que se realizan operaciones espaciales computacionalmente muy costosas. Para estas tareas se han desarrollado algoritmos de búsqueda heurística que hacen uso de técnicas de computación de altas prestaciones para reducir tiempos de ejecución. También se ha diseñado una arquitectura Web-SIG genérica pero fácilmente adaptable para la resolución de problemas concretos como pueden ser la dinamización de los mercado de tierras y la optimización de la gestión común de parcelas, dos aspectos importantes para el desarrollo rural. Las soluciones desarrolladas hacen uso de estándares y herramientas libres para favorecer la compatibilidad entre sistemas, abaratar costes, promover el e-Government y seguir las directivas de la Unión Europea en temas de información geoespacial.[Resumo] A terra é un factor estratéxico de suma importancia no desenvolvemento dunha determinada rexión. A terra ten que ser considerada como un ben capaz de xerar crecemento económico e da que se ten que sacar o máximo proveito. Nesta tese aplícanse as novas tecnoloxías a procesos da Administración de Terras que hasta agora ou ben non se facía, ou ben facíanse de forma rudimentaria. Un destes procesos é a ordenación territorial que, pola súa propia natureza, involucra gran cantidade de elementos con información xeográfica (parcelas, edificacións, entorno, ...) cos que realízanse operacións espaciais computacionalmente moi custosas. Para estas tarefas desenvolvéronse algoritmos de busca heurística que fan uso de técnicas de computación de altas prestacións para reducir tempos de execución. Tamén foi deseñada unha arquitecturaWeb-SIX xenérica pero doadamente adaptadable para a resolución de problemas concretos coma a dinamización dos mercados de terras e a optimización da xestión común de parcelas, dous aspectos importantes para o desenvolvemento rural. As solucións desenvolvidas fan uso de estándares e ferramentas libres para favorecer a compatibilidade entre sistemas, abaratar custos, promover o e-Government e seguir as directivas da Unión Europea en temas de información xeoespacial[Abstract] Land is a very important strategic factor for the rural development. Land must be considered as a good able to generate economic growth and thus try to take the most of it. This master thesis applies new technologies to Land Administration processes which until now had been done in a rudimentary way or even not done at all. One of these processes is the spatial planning that, by its very nature, involves high number of elements with geographic information (plots, buildings, environment, ...) and carry out computationally expensive spatial operations. Heuristic search algorithms have been developed for these issues and they use high performance computing techniques for reducing execution times. A generic architecture of an Web-GIS system has been also designed. It can be easily adapted to specific problems such as the invigoration of land markets and the optimization of common management of plots, two important issues for the rural development. The developed solutions use standards and license-free tools for encourage system compatibilities, reduce costs, support e-Government and follow the European Union directives in geospatial information issues

Uso de redes neuronales en el procesamiento de imágenes odontológicas

Tesis (Lic. en Física)--Universidad Nacional de Córdoba, Facultad de Matemática, Astronomía, Física y Computación, 2019.En este trabajo se aborda el problema de la detección de puntos característicos en imágenes médicas bidimensionales obtenidas mediante técnicas de rayos X, para lo cual se hizo uso de aprendizaje automático basado en redes neuronales artificiales. En particular, se abordó el problema de identificación de puntos característicos en imágenes cefalométricas de uso odontológico, no solo por su alto valor profesional, sino sobre todo porque este problema representa un gran desafío para el uso de inteligencia artificial en el reemplazo de expertos humanos. Se introdujo una arqui- tectura novedosa, no utilizada anteriormente en la literatura, la cual combina el uso de redes neuronales convolucionadas profundas con núcleos convolucionales de di- ferentes tamaños (capas inception) y la arquitectura de autoencoder para asociar a una imagen de entrada un mapa de probabilidades sobre la misma. Se utilizaron diferentes redes y se realizó un estudio comparativo, llegando a mostrar que estas redes introducidas tienen un excelente desempeño a la hora de identificar puntos característicos, superando las que se conocen en la bibliografía. En otras palabras, los modelos presentados en este trabajo mostraron una gran presición en detección de posiciones de landmarks, superando hasta en más de 7 puntos porcentuales los desempeños de los mejores modelos presentados en la literatura.In this work the problem of the detection of characteristic points in two-dimensional medical images obtained by X-ray techniques was addressed, for which automatic learning based on artificial neural networks is used. In particular, the problem of identifying characteristic points in odontologic cephalometric images was addres- sed, not only because of its high professional value, but above all because this pro- blem represents a great challenge for the use of artificial intelligence in the repla- cement of human experts. A novel architecture, not previously used in the literatu- re was introduced, which combines the use of deep convolutional neural networks with convolutional kernels of different sizes (inception layers) and the autoencoder architecture to associate an input image with a map of probabilities over it. Different networks were used and a comparative study was carried out, showing that these introduced networks have an excellent performance when identifying characteris- tic points, surpassing those that are known in the bibliography. In other words, the models presented in this work showed great precision in detecting landmarks posi- tions, surpassing the performance of the best models presented in the literature by more than 7 percentage points.Porta, Juan Ignacio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía, Física y Computación; Argentina

Path planning with pose SLAM

The probabilistic belief networks that result from standard feature-based simultaneous localization and map building (SLAM) approaches cannot be directly used to plan trajectories. The reason is that they produce a sparse graph of landmark estimates and their probabilistic relations, which is of little value to find collision free paths for navigation. In contrast, we argue in this paper that Pose SLAM graphs can be directly used as belief roadmaps (BRMs). The original BRM algorithm assumes a known model of the environment from which probabilistic sampling generates a roadmap. In our work, the roadmap is built on-line by the Pose SLAM algorithm. The result is a hybrid BRM-Pose SLAM method that devises optimal navigation strategies on-line by searching for the path with lowest accumulated uncertainty for the robot pose. The method is validated over synthetic data and standard SLAM datasets.Postprint (published version