Exploring spatial-frequency-sequential relationships for motor imagery classification with recurrent neural network

Abstract Background Conventional methods of motor imagery brain computer interfaces (MI-BCIs) suffer from the limited number of samples and simplified features, so as to produce poor performances with spatial-frequency features and shallow classifiers. Methods Alternatively, this paper applies a deep recurrent neural network (RNN) with a sliding window cropping strategy (SWCS) to signal classification of MI-BCIs. The spatial-frequency features are first extracted by the filter bank common spatial pattern (FB-CSP) algorithm, and such features are cropped by the SWCS into time slices. By extracting spatial-frequency-sequential relationships, the cropped time slices are then fed into RNN for classification. In order to overcome the memory distractions, the commonly used gated recurrent unit (GRU) and long-short term memory (LSTM) unit are applied to the RNN architecture, and experimental results are used to determine which unit is more suitable for processing EEG signals. Results Experimental results on common BCI benchmark datasets show that the spatial-frequency-sequential relationships outperform all other competing spatial-frequency methods. In particular, the proposed GRU-RNN architecture achieves the lowest misclassification rates on all BCI benchmark datasets. Conclusion By introducing spatial-frequency-sequential relationships with cropping time slice samples, the proposed method gives a novel way to construct and model high accuracy and robustness MI-BCIs based on limited trials of EEG signals

Strength and durability of self-compacting mortar with waste marble as sand substitution

The growing demand for infrastructure has led to an excessive use of natural resources. On the other hand, marble industry generates large quantities of wastes that could be recycled. In order to preserve natural resources, various methods can be used, including recycling waste into materials that can replace cement or aggregates. This paper investigates the effect of substituting various proportions by weight of natural sand (0 %, 15 %, 30 %, 75 % and 100 %) by marble waste fine particles (MW) on the behavior of a self-compacting mortar (SCM) in the fresh and hardened states. In addition, durability under sulfate attack was assessed. The results show that for an amount of substitution of natural sand by marble wastes not exceeding the proportion of 50 % by weight, a good workability and a flow time are obtained in the fresh state. An increase in compressive and flexural strength is obvious at 90 days of curing for 30 % and 50 % substitution of natural sand by marble waste. A decrease in the porosity at 30 % substitution, is observed. The durability against sulfate attacks was improved as the mortars with 0 % marble presented a decrease in strength, while those with 15 %, 30 % and 50 % marble substitution presented an increase in strength at 180 days of immersion. The specimens were examined by SEM and EDX to detect the possible presence of ettringite

Reconciling Component Based & Service Oriented Software Engineering: Application to e-Health System

Abstract-today, with the rise of the internet technology, software systems need to be dynamic, highly flexible and at the same time controllable and simple to maintain. To achieve this goal, recent studies have mixed the strength of Component Based Software Engineering (CBSE) and Service Oriented Software Engineering (SOSE). In the present paper, we show the importance of such collaboration through a critical e-Health case study: The Organ Transplant Management System (OTMS)

HACS: A Hybrid Framework for Continuous Flexible and Controlled Architecting

Systems like e-voting, e-banking or e-health must offer flexibility to continuously meet technical and legal changing requirements and must at the same time guarantee robustness to respect their security and sensitivity. Component Based Software Engineering (CBSE) and Service Oriented Software Engineering (SOSE) with their modular design represent the most suitable paradigms for those systems. They have strong complementary advantages, despite their similarities, their heterogeneity still hinders systems to benefit from both of them. In this paper, we propose a hybrid framework HACS (Hybrid Approach between Component and Service). HACS proposes to define sensitive systems as a hybrid architecture where the critical parts are controlled according to CBSE coupled to the flexibility and dynamism of SOSE. To address heterogeneity and make possible the substitution between hybrid components, HACS uses a common syntax with semantic annotations based on SAWSDL related to two ontologies; HACS ontology and domain ontology. We illustrate HACS all along the paper through an e-voting case study

A hybrid re-composition based on components and web services

International audienc

HACS: A Hybrid Framework for Continuous Flexible and Controlled Architecting

International audienc