A comparative performance analysis based on artificial intelligence techniques applied to three-phase induction motor drives

In this work, we introduced a new robust hybrid control to an induction motor (IM), based on the theory of fuzzy logic and variable structure with sliding-mode control (SMC). As the variations of both control system parameters and operating conditions occur, the conventional control methods may not be satisfied further. Fuzzy tuning schemes are employed to improve control performance and to reduce chattering in the sliding mode. The combination of these two theories has given high performance and fast dynamic response with no overshoot. As it is very robust, it is insensitive to process parameters variation and external disturbances

Apprentissage dynamique du nombre d'états d'un modèle de markov caché à observations continues : Application au tri de formulaires

Dans le cadre de la reconnaissance automatique de types de formulaires avec champs manuscrits et sans aucun signe de référence, basée sur une description de la structure physique du formulaire, nous sommes amenés à représenter un formulaire par un modèle de Markov caché pseudo-2D (PHMM). Ce modèle est constitué d'un graphe de super-états. A chaque super-état on associe un modèle de Markov caché secondaire (HMM) dont les observations sont continues. Nous exposons pourquoi la méthode classique des k-moyennes est mal adaptée à notre problème, puis nous détaillons une nouvelle méthode générale qui prend mieux en compte la réalité physique des états, en les situant dans l'espace de représentation des caractéristiques, et en les construisant dynamiquement par agrégation progressive des séquences d'observations. Ce n'est qu'à la fin du processus d'agrégation que le nombre d'états du modèle stochastique initial est connu

Recipe adaptation and new recipe development for high temperature heat treatment of North American wood species

The thermal treatment of wood at high temperatures is an environment friendly and commercially viable alternative wood modification technology. In this process, wood is heated to temperatures above 200ºC. This modifies the structure of wood and improves its hardness, dimensional stability, and resistance to biological attacks compared to those of the untreated wood. Its color also becomes darker and more attractive. However, this treatment may cause a decrease in wood elasticity. Therefore, optimization of the treatment parameters is necessary for a quality product. In addition, the high temperature heat-treatment processes for wood were first developed in Europe, and the recipes used for the European species were not necessarily applicable to the North American species. Thus, adaptation of the technologies to the latter species was necessary. The industrialists in the Saguenay-Lac-St-Jean region of Quebec brought two heat treatment technologies (Bois Perdure from France and Thermowood from Finland) to Canada. The adaptation of the technology is a very costly procedure at industrial scale. The Research Group on the Thermotransformation of Wood (GRTB – Groupe de recherche sur la thermotransformation du bois) at the University of Quebec at Chicoutimi (UQAC) which works closely with these industries developed a method for adapting the existing recipes to the North American species as well as for developing new ones for other species. UQAC is the first North American university which has such a unique research structure to carry out this type of research. The recipe development starts in a laboratory scale furnace. The high temperature heat-treatment experiments are carried out in a thermogravimetric system under different conditions until a promising set of conditions is identified for the properties sought by the industry. Consequently, the trends are identified for a given species. To determine the properties, various characterization tests (bending, dimensional stability, screw withdrawal, etc.) are done. Then, the heat treatment trials in a prototype furnace are carried out to finalize the recipe. This is followed by trials in an industrial-scale furnace for validation of the results

Modelling of high temperature heat treatment of wood using thermowood technology

Heat treatment of wood at relatively high temperatures (in the range of 180–240°C) is an effective method to improve the dimensional stability and to increase the biological durability of wood. During the heat treatment process, the heat and mass transfer takes place between the solid and the drying medium, and the moisture evaporation occurs within the solid due to the capillarity action and diffusion. In this article, a coupling method is presented for high temperature heat treatment of wood based on ThermoWood technology. A three-dimensional mathematical model considering the simultaneous unsteady heat and moisture transfer between a gas phase and a solid phase during heat treatment has been developed. The conservation equations for the wood part are obtained using the diffusion equation with variable diffusion coefficients, and the 3-dimensional incompressible Reynolds-averaged NavierStokes equations have been solved for the flow field. The coupling between the two parts is achieved by expressing the continuity of the state variables and their respective fluxes through the interface. A detailed discussion of the computational model and the solution algorithm is given

High-Throughput Label-Free Isolation of Heterogeneous Circulating Tumor Cells and CTC Clusters from Non-Small-Cell Lung Cancer Patients.

(1) Background: Circulating tumor cell (CTC) clusters are emerging as clinically significant harbingers of metastases in solid organ cancers. Prior to engaging these CTC clusters in animal models of metastases, it is imperative for technology to identify them with high sensitivity. These clusters often present heterogeneous surface markers and current methods for isolation of clusters may fall short. (2) Methods: We applied an inertial microfluidic Labyrinth device for high-throughput, biomarker-independent, size-based isolation of CTCs/CTC clusters from patients with metastatic non-small-cell lung cancer (NSCLC). (3) Results: Using Labyrinth, CTCs (PanCK+/DAPI+/CD45-) were isolated from patients (n = 25). Heterogeneous CTC populations, including CTCs expressing epithelial (EpCAM), mesenchymal (Vimentin) or both markers were detected. CTCs were isolated from 100% of patients (417 +/- 1023 CTCs/mL). EpCAM- CTCs were significantly greater than EpCAM+ CTCs. Cell clusters of \u3e/=2 CTCs were observed in 96% of patients-of which, 75% were EpCAM-. CTCs revealed identical genetic aberrations as the primary tumor for RET, ROS1, and ALK genes using fluorescence in situ hybridization (FISH) analysis. (4) Conclusions: The Labyrinth device recovered heterogeneous CTCs in 100% and CTC clusters in 96% of patients with metastatic NSCLC. The majority of recovered CTCs/clusters were EpCAM-, suggesting that these would have been missed using traditional antibody-based capture methods

Coherent WDM transmission using quantum-dash mode-locked laser diodes as multi-wavelength source and local oscillator

Quantum-dash (QD) mode-locked laser diodes (MLLD) lend themselves as chip-scale frequency comb generators for highly scalable wavelength-division multiplexing (WDM) links in future data-center, campus-area, or metropolitan networks. Driven by a simple DC current, the devices generate flat broadband frequency combs, containing tens of equidistant optical tones with line spacings of tens of GHz. Here we show that QD-MLLDs can not only be used as multi-wavelength light sources at a WDM transmitter, but also as multi-wavelength local oscillators (LO) for parallel coherent reception. In our experiments, we demonstrate transmission of an aggregate data rate of 4.1 Tbit/s (23x45 GBd PDM-QPSK) over 75 km standard single-mode fiber (SSMF). To the best of our knowledge, this represents the first demonstration of a coherent WDM link that relies on QD-MLLD both at the transmitter and the receiver

Silicon-organic hybrid (SOH) devices and their use in comb-based communication systems

Advanced wavelength-division multiplex-ing (WDM) requires both efficient multi-wavelength light sources to generate optical carriers and highly scalable photonic-electronic interfaces to encode data on these carriers. In this paper, we give an overview on our recent progress regarding silicon-organic hy-brid (SOH) integration and comb-based WDM transmission

Identification and characterization of DGA2, an acyltransferase of the DGAT1 acyl-CoA:diacylglycerol acyltransferase family in the oleaginous yeast Yarrowia lipolytica. New insights into the storage lipid metabolism of oleaginous yeasts

Triacylglycerols (TAG) and steryl esters (SE) are the principal storage lipids in all eukaryotic cells. In yeasts, these storage lipids accumulate within special organelles known as lipid bodies (LB). In the lipid accumulation-oriented metabolism of the oleaginous yeast Yarrowia lipolytica, storage lipids are mostly found in the form of TAG, and only small amounts of SE accumulate. We report here the identification of a new DAG acyltransferase gene, DGA2, homologous to the ARE genes of Saccharomyces cerevisiae. This gene encodes a member of the type 1 acyl-CoA:diacylglycerol acyltransferase family (DGAT1), which has not previously been identified in yeasts, but is commonly found in mammals and plants. Unlike the Are proteins in S. cerevisiae, Dga2p makes a major contribution to TAG synthesis via an acyl-CoA-dependent mechanism and is not involved in SE synthesis. This enzyme appears to affect the size and morphology of LB, suggesting a direct role of storage lipid proteins in LB formation. We report that the Are1p of Y. lipolytica was essential for sterol esterification, as deletion of the encoding gene (ARE1) completely abolished SE synthesis. Unlike its homologs in yeasts, YlARE1 has no DAG acyltransferase activity. We also reconsider the role and function of all four acyltransferase enzymes involved in the final step of neutral lipid synthesis in this oleaginous yeast

Organisational culture and TQM implementation: investigating the mediating influences of multidimensional employee readiness for change

Despite the robust evidence for the direct relationship between organisational culture (OC) and total quality management (TQM), the mechanisms underlying this relationship are not fully explored and have received little empirical attention. This paper extends prior TQM research in a novel way by building and then empirically testing a theoretical model that includes the mediating role of employee readiness for change dimensions (ERFCs) in the OC-TQM relationship. The paper adds value through its contextual originality in being one of the first studies that are conducted in Algeria; which has special ties with the EU geographically, politically and economically. The empirical data for this study was drawn by distributing a questionnaire to 226 middle managers of Algerian firms. Our findings support the mediating roles of two dimensions of ERFC, namely: self-efficacy (ERFC1) and personal valence (ERFC4) in the OC-TQM relationship. This indicates that the improvement in TQM implementation is not a direct consequence of supportive organisational culture but rather of self-efficacy and personal valence transferring the impact of group and adhocracy culture to TQM. To this effect, these results go beyond previous research and contribute significantly in explaining the underlying psychological mechanisms in the OC-TQM relationships model