A comparative study for multiple visual concepts detection in images and videos

Automatic indexing of images and videos is a highly relevant and important research area in multimedia information retrieval. The difficulty of this task is no longer something to prove. Most efforts of the research community have been focusing, in the past, on the detection of single concepts in images/videos, which is already a hard task. With the evolution of information retrieval systems, users’ needs become more abstract, and lead to a larger number of words composing the queries. It is important to think about indexing multimedia documents with more than just individual concepts, to help retrieval systems to answer such complex queries. Few studies addressed specifically the problem of detecting multiple concepts (multi-concept) in images and videos. Most of them concern the detection of concept pairs. These studies showed that such challenge is even greater than the one of single concept detection. In this work, we address the problem of multi-concept detection in images/videos by making a comparative and detailed study. Three types of approaches are considered: 1) building detectors for multi-concept, 2) fusing single concepts detectors and 3) exploiting detectors of a set of single concepts in a stacking scheme. We conducted our evaluations on PASCAL VOC’12 collection regarding the detection of pairs and triplets of concepts. We extended the evaluation process on TRECVid 2013 dataset for infrequent concept pairs’ detection. Our results show that the three types of approaches give globally comparable results for images, but they differ for specific kinds of pairs/triplets. In the case of videos, late fusion of detectors seems to be more effective and efficient when single concept detectors have good performances. Otherwise, directly building bi-concept detectors remains the best alternative, especially if a well-annotated dataset is available. The third approach did not bring additional gain or efficiency.     

A New Full‐Order Sliding Mode Observer Based Rotor Speed and Stator Resistance Estimation for Sensorless Vector Controlled Pmsm Drives

Sensorless control of a permanent magnetsynchronous motor (PMSM) at low speed remains a challenging task. In this paper, a sensorless vector control of PMSM using a new structure of a sliding mode observer (SMO) is proposed. To remove the mechanical sensors, a full‐order (FO‐SMO) is built to estimate the rotor position and speed of PMSM drives. The FO‐SMO, which replaces a sign function by a sigmoid function, can reduce the chattering phenomenon. In order to overcome time delay, we cancel the low pass filter. This sensorless speed control shows great sensitivity to stator resistance and system noise. To improve the robustness of sensorless vector control, a full‐order SMO technique has been used for stator resistance estimation. A novel stator resistance estimator is incorporated into the sensorless drive to compensate for the effects of stator resistance variation. The validity of the proposed FO‐SMO with a 1.1 kw low‐speed PMSM sensorless vector control is demonstrated by experiments. In this paper, experimental results for FO‐SMO, back‐EMF SMO and MRAS techniques were obtained with fixed point DSP‐based (TMS320F240).     

A novel approach for generic home emergency management and remote monitoring

This paper presents a novel home emergency management system (HEMS) for managing home emergency situations. The proposed solution is a generic and based on normalized technologies. First, we have identified a set of requirements that a robust HEMS should satisfy (interoperability, security, mobility, etc). Then, we have opted for an extended finite‐state machine to detect and manage emergency situations. We also adopted WebRTC to enable communication in an interoperable manner. For securing our HEMS, we have used HTTPS, password, contextual role–based access control, and we have finally installed all the public servers into a protected area. The result obtained from the test‐bed demonstrates that the proposed HEMS fills all the listed requirements. Furthermore, it gives very interesting results in terms of round‐trip delay time and scalability.     

Improving Arabic information retrieval using word embedding similarities

Term mismatch is a common limitation of traditional information retrieval (IR) models where relevance scores are estimated based on exact matching of documents and queries. Typically, good IR model should consider distinct but semantically similar words in the matching process. In this paper, we propose a method to incorporate word embedding (WE) semantic similarities into existing probabilistic IR models for Arabic in order to deal with term mismatch. Experiments are performed on the standard Arabic TREC collection using three neural word embedding models. The results show that extending the existing IR models improves significantly baseline bag-of-words models. Although the proposed extensions significantly outperform their baseline bag-of-words, the difference between the evaluated neural word embedding models is not statistically significant. Moreover, the overall comparison results show that our extensions significantly improve the Arabic WordNet based semantic indexing approach and three recent WE-based IR language models.     

Short Palm Tree Fibers Polyolefin Composites: Effect of Filler Content and Coupling Agent on Physical Properties

Short date palm tree lignocellulosic fibers have been used as a reinforcing phase in commodity thermoplastic matrices [poly(propylene) and low density polyethylene]. Compatibilization of the fibers was carried out with the use of maleic anhydride copolymers. The morphology, thermal and mechanical properties of the resulting composites were characterized using SEM, DSC and tensile tests. The reinforcing capability of the unmodified fibers was found to depend on the nature of the matrix and the main parameter governing the composite behavior was the degree of crystallinity of the matrix. Compatibilization was reported to enhance the mechanical performances for both sets of composites up to a critical amount of compatibilizer beyond which the degree of crystallinity of the matrix decreases.

     

Study of corrosion inhibition properties of Schinus molle essential oil on carbon steel in HCl

The inhibitory action of Schinus molle L. essential oil was investigated for the corrosion of carbon steel in 1 M hydrochloric acid solution using weight loss, polarization curves, and electrochemical impedance spectroscopy. The inhibition efficiency has increased with the increase of the inhibitor concentration, reaching a value of up to 70% at 2 g/L.     

Structure–Activity Relationship,Biological, and Pharmacological Characterization of the Proline Sulfonamide ACT‐462206: a Potent,Brain‐Penetrant Dual Orexin 1/Orexin 2 Receptor Antagonist

The orexin system consists of two G‐protein‐coupled receptors, the orexin 1 and orexin 2 receptors, widely expressed in diverse regions of the brain, and two peptide agonists, orexin A and orexin B, which are produced in a small assembly of neurons in the lateral hypothalamus. The orexin system plays an important role in the maintenance of wakefulness. Several compounds (almorexant, SB‐649868, suvorexant) have been in advanced clinical trials for treating primary insomnia. ACT‐462206 is a new, potent, and selective dual orexin receptor antagonist (DORA) that inhibits the stimulating effects of the orexin peptides at both the orexin 1 and 2 receptors. It decreases wakefulness and increases non‐rapid eye movement (non‐REM) and REM sleep while maintaining natural sleep architectures in rat and dog electroencephalography/electromyography (EEG/EMG) experiments. ACT‐462206 shows anxiolytic‐like properties in rats without affecting cognition and motor function. It is therefore a potential candidate for the treatment of insomnia.     

Preparation of dendrimer polyol/mesoporous silica nanocomposite for reversible CO2 adsorption: Effect of pore size and polyol content

This paper focuses on the synthesis of polyol/MCM-48 nanocomposite materials with different percentages of polyalcohol dendrimer H20. The obtained materials were used for CO₂ adsorption. CO₂-TPD analysis showed that the samples containing 1 and 3 wt% of H20 dendrimer have low CO₂ adsorption capacity due to the occupation of active sites, The sample prepared with 0.5 wt% of H20 dendrimer exhibited higher adsorption capacity and thermal stability. The affinity toward CO₂ was found to be mainly due to the presence of organic moiety within the MCM-48 pores.     

Experimental and numerical investigation of the sliding behaviour in a fretting contact between poly (methylmethacrylate) and a glass counterface

The fretting conditions in a contact between poly (methylmethacrylate) and a rigid counterface have been investigated using both experiments and finite elements computations. The computation of the microdisplacements in the contact area during a tangential loading allowed the determination of the critical displacement for transition from partial sliding to gross sliding conditions. These conditions were mapped in friction maps as a function of the contact loading parameters (i.e., normal load and displacement amplitude) and the friction coefficient. This analysis was performed assuming that the polymer behaved elastically and that the friction obeyed Coulomb's law. Experimental results were found to be in accordance with the numerical predictions, despite the fact that some plastic deformation of the polymer surface occurred during tangential loading.