764 research outputs found

    Looking for an Accounting Identity : The Case of Romania during the 20th Century

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    This article aims to provide a longitudinal presentation of developments in Romanian accounting during the 20th century and to propose a neo-institutional explanation of this evolution. The historical research methodology employed here is complex. We use a constructive research philosophy, an inductive research approach, a mixture of research types (narrative, oral and interpretative histories), content analysis as our research method and four types of data collection (archives, secondary data, observations and interviews). The interpretative analysis is based on the neo-institutional theoretical framework. The study identifies a “homeAgrown”, normative influence in Romanian accounting practices during the first 50 years of the twentieth century, a coercive one, imposed until 1989, by a centralized communist system, and from 1989 to the present, a mixed isomorphism oriented around French, European and International accounting systems. Lacking a period of introspection, the authors feel that there is little hope that Romanian accounting will reA discover its unique culture, or will manage to build upon or improve its indigenous base in the current international contextAccounting ; Historical approach ; Neo-institutionalism ; XXth century ; Romania

    Looking for an Accounting Identity : The Case of Romania during the 20th Century

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    Cahier de recherche n° 2010-03 E2This article aims to provide a longitudinal presentation of developments in Romanian accounting during the 20th century and to propose a neo-institutional explanation of this evolution. The historical research methodology employed here is complex. We use a constructive research philosophy, an inductive research approach, a mixture of research types (narrative, oral and interpretative histories), content analysis as our research method and four types of data collection (archives, secondary data, observations and interviews). The interpretative analysis is based on the neo-institutional theoretical framework. The study identifies a “homeAgrown”, normative influence in Romanian accounting practices during the first 50 years of the twentieth century, a coercive one, imposed until 1989, by a centralized communist system, and from 1989 to the present, a mixed isomorphism oriented around French, European and International accounting systems. Lacking a period of introspection, the authors feel that there is little hope that Romanian accounting will reA discover its unique culture, or will manage to build upon or improve its indigenous base in the current international contex

    La crise économique et financière impacte-t-elle la mission d'audit légal et de certification des comptes ?

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    L'article vise à montrer comment le commissaire aux comptes (CAC) doit adapter sa mission à un contexte de crise économique et financière. En effet, le CAC doit mettre en œuvre des diligences spécifiques au contexte économique, puisque certains risques sont ainsi amplifiés, comme ceux tenant à la continuité d'exploitation et à la mauvaise estimation du résultat comptable. En outre, le rapport général du commissaire peut lui aussi être nuancé en raison de l'incertitude pesant sur certains éléments, ce qui peut induire des asymétries d'information. L'analyse théorique de la situation est complétée par une étude de cas portant sur une société située dans un secteur touché par la crise financière actuelle, à savoir la fabrication de matériels électriques de pointe.crise financière ; commissaires aux comptes ; mission générale ; France ; étude de cas ; financial crisis ; auditors ; France ; case study

    Acoustic Seabed Classification using Fractional Fourier Transform

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    In this paper we present a time-frequency approach for acoustic seabed classification. Work reported is based on sonar data collected by the Volume Search Sonar (VSS), one of the five sonar systems in the AN/AQS-20. The Volume Search Sonar is a beamformed multibeam sonar system with 27 fore and 27 aft beams, covering almost the entire water volume (from above horizontal, through vertical, back to above horizontal). The processing of a data set of measurement in shallow water is performed using the Fractional Fourier Transform algorithm in order to determine the impulse response of the sediment. The Fractional Fourier transform requires finding the optimum order of the transform that can be estimated based on the properties of the transmitted signal. Singular Value Decomposition and statistical properties of the Wigner and Choi-Williams distributions of the bottom impulse response are employed as features which are, in turn, used for classification. The Wigner distribution can be thought of as a signal energy distribution in joint time-frequency domain. Results of our study show that the proposed technique allows for accurate sediment classification of seafloor bottom data. Experimental results are shown and suggestions for future work are provided

    Time-Frequency Transform Techniques for Seabed and Buried Target Classification

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    An approach for processing sonar signals with the ultimate goal of ocean bottom sediment classification and underwater buried target classification is presented in this paper. Work reported for sediment classification is based on sonar data collected by one of the AN/AQS-20’s sonars. Synthetic data, simulating data acquired by parametric sonar, is employed for target classification. The technique is based on the Fractional Fourier Transform (FrFT), which is better suited for sonar applications because FrFT uses linear chirps as basis functions. In the first stage of the algorithm, FrFT requires finding the optimum order of the transform that can be estimated based on the properties of the transmitted signal. Then, the magnitude of the Fractional Fourier transform for optimal order applied to the backscattered signal is computed in order to approximate the magnitude of the bottom impulse response. Joint time-frequency representations of the signal offer the possibility to determine the timefrequency configuration of the signal as its characteristic features for classification purposes. The classification is based on singular value decomposition of the time-frequency distributions applied to the impulse response. A set of the largest singular values provides the discriminant features in a reduced dimensional space. Various discriminant functions are employed and the performance of the classifiers is evaluated. Of particular interest for underwater under-sediment classification applications are long targets such as cables of various diameters, which need to be identified as different from other strong reflectors or point targets. Synthetic test data are used to exemplify and evaluate the proposed technique for target classification. The synthetic data simulates the impulse response of cylindrical targets buried in the seafloor sediments. Results are presented that illustrate the processing procedure. An important characteristic of this method is that good classification accuracy of an unknown target is achieved having only the response of a known target in the free field. The algorithm shows an accurate way to classify buried objects under various scenarios, with high probability of correct classification

    Sonar Signal Enhancement Using Fractional Fourier Transform

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    In this paper we present an approach for signal enhancement of sonar signals. Work reported is based on sonar data collected by the Volume Search Sonar (VSS), as well as VSS synthetic data. The Volume Search Sonar is a beamformed multibeam sonar system with 27 fore and 27 aft beams, covering almost the entire water volume (from above horizontal, through vertical, back to above horizontal). The processing of a data set of measurement in shallow water is performed using the Fractional Fourier Transform algorithm. The proposed technique will allow efficient determination of seafloor bottom characteristics and bottom type using the reverberation signal. A study is carried out to compare the performance of the presented method with conventional methods. Results are shown and future work and recommendations are presented

    Global Carleman inequalities for parabolic systems and applications to controllability

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    This paper has been conceived as an overview on the controllability properties of some relevant (linear and nonlinear) parabolic systems. Specifically, we deal with the null controllability and the exact controllability to the trajectories. We try to explain the role played by the observability inequalities in this context and the need of global Carleman estimates. We also recall the main ideas used to overcome the difficulties motivated by nonlinearities. First, we considered the classical heat equation with Dirichlet conditions and distributed controls. Then we analyze recent extensions to other linear and semilinear parabolic systems and/or boundary controls. Finally, we review the controllability properties for the Stokes and Navier–Stokes equations that are known to date. In this context, we have paid special attention to obtaining the necessary Carleman estimates. Some open questions are mentioned throughout the paper. We hope that this unified presentation will be useful for those researchers interested in the field.Ministerio de Educación y Cienci

    A numerical framework for modelling tire mechanics accounting for composite materials, large strains and frictional contact

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    Presentation delivered by Alejandro Cornejo from CIMNE during the 17th International Conference on Computational Plasticity, Fundamentals and Applications (COMPLAS) taking place from 5 – 7 of September in Barcelona, Spain.The Fatigue4Light project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 10100684

    Fatigue behaviour of Glass-Fiber-Reinforced Polymers Numerical versus experimental characterisation

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    Presentation delivered by Bàrbara Alcayde from CIMNE during the 17th International Conference on Computational Plasticity, Fundamentals and Applications (COMPLAS) taking place from 5 – 7 of September in Barcelona, Spain.The Fatigue4Light project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 10100684

    Mapping the Spatial Distribution of a Disease-Transmitting Insect in the Presence of Surveillance Error and Missing Data

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    Maps of the distribution of epidemiological data often ignore surveillance error or possible correlations between missing information and outcomes. We analyse presence–absence data at the household level (12050 points) of a disease‐carrying insect in Mariano Melgar, Peru, collected as part of the Arequipan Ministry of Health\u27s efforts to control Chagas disease. We construct a Bayesian hierarchical model to locate regions that are vulnerable to under‐reporting due to surveillance error, accounting for variability in participation due to infestation status. The spatial correlation in the data allows us to identify relative inspector sensitivity and to elucidate the relationship between participation and infestation. We show that naive estimates of prevalence would be biased by surveillance error and missingness at random assumptions. We validate our results through simulations and observe how randomized inspector assignments may improve prevalence estimates. Our results suggests that bias due to imperfect observations and missingness at random can be assessed and corrected in prevalence estimates of spatially auto-correlated binary variables
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