Search results for "Data mining"
showing 10 items of 907 documents
A semiparametric approach to estimate reference curves for biophysical properties of the skin
2006
Reference curves which take one covariable into account such as the age, are often required in medicine, but simple systematic and efficient statistical methods for constructing them are lacking. Classical methods are based on parametric fitting (polynomial curves). In this chapter, we describe a new methodology for the estimation of reference curves for data sets, based on nonparametric estimation of conditional quantiles. The derived method should be applicable to all clinical or more generally biological variables that are measured on a continuous quantitative scale. To avoid the curse of dimensionality when the covariate is multidimensional, a new semiparametric approach is proposed. Th…
Are Neural Networks Imitations of Mind?
2015
Artificial neural networks are often understood as a good way to imitate mind through the web structure of neurons in brain, but the very high complexity of human brain prevents to consider neural networks as good models for human mind;anyway neural networks are good devices for computation in parallel. The difference between feed-forward and feedback neural networks is introduced; the Hopfield network and the multi-layers Perceptron are discussed. In a very weak isomorphism (not similitude) between brain and neural networks, an artificial form of short term memory and of acknowledgement, in Elman neural networks, is proposed.
A probabilistic expert system for predicting the risk of Legionella in evaporative installations
2011
Research highlights? The bacterium Legionella usually lives in water sources such as cooling towers. ? We discuss a probabilistic expert system for predicting the risk of Legionella. ? The expert system has a master-slave architecture. ? The inference engine is implemented through Bayesian reasoning. ? Bayesian networks model and connect relationships for chemical and physical variables. Early detection in water evaporative installations is one of the keys to fighting against the bacterium Legionella, the main cause of Legionnaire's disease. This paper discusses the general structure, elements and operation of a probabilistic expert system capable of predicting the risk of Legionella in rea…
On the definition of generic multi-layered ontologies for urban applications
2000
Cooperation of information systems is essential for providing decision support for urban management applications. This involves sharing data across collections of the heterogeneous information systems that are used to manage large urban infrastructures. The objective of this work is to define a spatial ontology to describe key features of urban applications, providing a foundation for semantic reconciliation among heterogeneous spatial information sources. We propose a multi-layered ontologies definition framework consisting of ontology layers which are composed of a generic functional structure and one or more domain ontologies. The functional structure embodies general ontological concept…
2015
Abstract. The coupling of Earth system model components, which work on different grids, into an Earth System Model (ESM) provokes the necessity to transfer data from one grid to another. Additionally, each of these model components might require data import onto its specific grid. Usually, one of two approaches is used: Either all input data is preprocessed to the employed grid, or the imported data is interpolated on-line, i.e. during model integration to the required grid. For the former, each change in the model resolution requires the re-preprocessing of all data. The latter option implies that in each model integration computing time is required for the grid mapping. If all components …
CAD modelling of the human femur taking into account the structure of the bone
2021
The use of 3D models of the human bone system has great utility in the biomechanical study, due to the fact that these structures cannot be analyzed or tested in vivo. Within this paper, taking into consideration its real bone structure, the human femur CAD modelling is established. Firstly, a preliminary anatomical study is done, in order to highlight the fact that the thigh bone is a heterogeneous structure, consisting of several entities with different mechanical characteristics. The modelling starts from a homogenous 3D model of the femur, from which, every single separate entity is designed and finally they are assembled within a single product assembly. Therefore, the final result ens…
Classification and Automated Interpretation of Spinal Posture Data Using a Pathology-Independent Classifier and Explainable Artificial Intelligence (…
2021
Clinical classification models are mostly pathology-dependent and, thus, are only able to detect pathologies they have been trained for. Research is needed regarding pathology-independent classifiers and their interpretation. Hence, our aim is to develop a pathology-independent classifier that provides prediction probabilities and explanations of the classification decisions. Spinal posture data of healthy subjects and various pathologies (back pain, spinal fusion, osteoarthritis), as well as synthetic data, were used for modeling. A one-class support vector machine was used as a pathology-independent classifier. The outputs were transformed into a probability distribution according to Plat…
Optimal gossip algorithm for distributed consensus SVM training in wireless sensor networks
2009
In this paper, we consider the distributed training of a SVM using measurements collected by the nodes of aWireless Sensor Network in order to achieve global consensus with the minimum possible inter-node communications for data exchange. We derive a novel mathematical characterization for the optimal selection of partial information that neighboring sensors should exchange in order to achieve consensus in the network. We provide a selection function which ranks the training vectors in order of importance in the learning process. The amount of information exchange can vary, based on an appropriately chosen threshold value of this selection function, providing a desired trade-off between cla…
Multiscale analyses and characterizations of surface topographies
2018
International audience; This work studies multiscale analyses and characterizations of surface topographies from the engineering and scientific literature with an emphasis on production engineering research and design. It highlights methods that provide strong correlations between topographies and performance or topographies and processes, and methods that can confidently discriminate topographies that were processed or that perform differently. These methods have commonalities in geometric characterizations at certain scales, which are observable with statistics and measurements. It also develops a semantic and theoretical framework and proposes a new system for organizing and designating …
Usage of European census data for sustainable land management – German case study
2014
AbstractThis paper describes opportunities and results of the usage of high resolution census data for sustainable land management. Following European Union requirements many countries in Europe have counted their population and other indicators in 2011. To take full benefit of the very rich high resolution census data in Germany some country specific problems had to be solved. By applying a semi-automatic procedure the study describes in which way the official topographical and property information systems provided by the surveying authorities are used to determine the boundaries of small scale census units. Linking the census data to the corresponding geographical units enables public adm…