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Industrial Customers are dispersed at various levels of the electrical network and fed together with other customers' categories in a distributed environment. Optimizing industrial processes in the presence of other customers' categories supplied by the same infrastructure is a challenging issue. Existing studies have analyzed the effect of different Industrial Demand Response Programs on the distribution network, which also supplies other customers' categories. They show the need for improving the distribution performance although multiple demand response programs have been suggested for this purpose. In this paper, a new approach is presented considering an optimal synchronized process among all consumers' categories. It shows that the balance between generation and demand is maintained, the customer satisfaction is guaranteed, the profit is maximized and the cost is minimized for all customers. Various time constraints set by different industry productions are considered in the optimization process. Fairness problems, multiple pricing schemes and formulation for the same are elaborated. The method is validated through a simulation on Matlab using K-Means Clustering and multi-objective particle swarm optimization (MOPSO) along with data prediction.

Prosthetic technology is rapidly advancing but there's a catch. Regardless the technology or the material used, a minimum cost is still high. One of the problems relates to the fact that the conventional socket fabrication process is still used. This method is based on subjective estimations of the involved specialists and feedbacks of the patients. This process consumes remarkable amount of time, manpower and materials. Research works are needed to design new efficient and low-cost alternative techniques for the socket design. This technique should definitely be based on CAD-CAM methods. Therefore, the first step toward this objective is to establish an accurate numeric model for evaluating and optimizing the design process. In this present work, we developed a new approach to simulate the stump soft tissue deformation and stump-socket interaction using Mass-Spring System (MSS) approach and a point-to-surface contact formulation. A novel Mass-Spring System with corrective spring (MSS-CS) model was developed and evaluated. A node-to-surface contact formulation was also integrated and evaluated. The MSS-CS model and contact formulation were evaluated with primitive geometrical object and a stump-socket model. Moreover, a finite element model of the stump-socket interaction was also developed using Abaqus to evaluate the proposed approach. Obtained results show that the proposed contact formulation has a very good precision level and the contact pressures on the interface between the elastic and rigid bodies are very close to the analytical solutions. The comparison with Abaqus showed a qualitative concordance for the contact pressure. However, quantitative deviation remains high [25-50]% at the peak contact pressure due to different contact formulations. In particular, our MSS-CS approach is more efficient than Abaqus simulation in term of computational time and cost. A novel approach was proposed to model soft tissue deformation and stump-socket interaction in an efficient and accurate manner. As perspectives, this present approach for a real-time simulation of the stump-socket interaction could be used in a real-time CAD-CAM platform to provide a cost-effective socket manufacturing process.

This paper shows that the Demand Response Program is not sufficient to solve the problem of high penetration level of Plug-in Electric Vehicles (PEVs), even when energy management systems are used in homes. In the presence of Time-varying electricity price, PEVs tend to charge during low price periods. The problem starts when the number of PEVs exceeds a certain threshold. A total load of all homes on a transformer may exceed its capacity and create high peak-demand during low-electricity price. To overcome this situation, we propose a novel Soft-Constrained Distributed Strategy. The novelty consists of defining a new distributed information exchange between Power Utility and end-users, new constraints are developed at home level taking into account the transformer and Distribution Network's technical limits, and a new optimization model is proposed to implement the strategy. A case study is conducted using data provided by Hydro-Quebec. Simulations and comparative results show the validity of our approach. The proposed strategy reduces the peak–demand, energy loss, depreciation cost, transformer's Loss Of Life, and voltage deviations. Lastly, our study shows that it is not necessary for the power utility (e.g. Hydro-Quebec) to upgrade all Distribution Transformers on the network and the infrastructure during the increasing penetration of PEVs.

Massive penetration of plug-in electric vehicles (EVs) may create challenges in the near future for the distribution network. Moreover, this may lead to an increase of the transformers’ aging rate and a reduction of the financial profits. In this paper, a novel approach is proposed, in which the operational margin of the transformer is optimized based on the transformer’s internal characteristics, its loss of life, and the variation of the ambient temperature. This operational power limit should not be exceeded to guarantee that the loss of life of the transformer is equal to or less than the one provided by the manufacturer. For validation purposes, a comparative study between the conventional method and the suggested one is presented. This paper is applied to a parking lot for charging EVs, which is supplied by a distribution transformer. In contrary to the conventional method, the one suggested in this paper can guarantee a predefined transformer loss of life. Simulation results show that the proposed method increases the transformer lifetime, reduces the loss of life, and reduces its depreciation cost by 63% in certain conditions. In addition, it increases the financial profit for the parking lot’s owner up to 10% during cold weather.

Open water evaporation is influenced by several meteorological parameters such as: irradiance, soil temperature, relative humidity, atmospheric pressure and wind speed. However, dealing with that matter, in a case of measurements scarcity, is a challenging task. To overcome this problem, the authors sought a less-dimensional method to estimate lake evaporation. This technique takes into account only three weather variables: temperature, relative Humidity and dew point. In fact, the approach is summarized as follows: 1- using Levenberg-Marquardt algorithm, a Nonlinear Regression model based on Magnus formula is trained and tested to estimate the dew point. 2- a simplified Penman formula provides an estimate for the lake evaporation rate. To test the approach effectiveness, the suggested method was applied on Qaraoun Lake - Lebanon. Upon testing, the regression model exhibited high accuracy with a goodness of fit value equal to 0.99. Afterwards, the evaporation rates were estimated using Penman formula. Unfortunately, evaporation measurements are not available on site to carry the testing procedures. Instead, outcomes were investigated and compared with the monthly evaporation average retrieved from the nearest region to the lake. Estimated rates were reasonably good with a correlation coefficient equal to 0.89 and mean absolute percentage error around 9.8%. At the final stage of this study, sensitivity analysis is performed to quantify the impact of temperature and relative humidity change on evaporation. Overall, the achieved results were reliable enough to carry out a further assessment of the economic impact of evaporation losses from Qaraoun reservoir on the hydropower generation and on the irrigation sector.

Biologists have uncovered some of the most basic mechanisms by which normal cells develop into cancerous tumors. These biological theories can be transformed into adequate mathematical models. For this reason, we attempt to study the evolution of cancer cells using the GWBP. The purpose of this paper is to study how the genetic algorithm (GA) can be used to follow the evolution of cancer and find optimal chemotherapeutic treatments.The development of GWBP give us the evolution of number of cancer cells for any patient if the death rate will defined experimentally, according to this value we can simulate the suitable chemotherapy treatments which cause the death of cancer, then determine the minimum dosage treatment injected using the GA optimization method. Analysis of these results gives us the objective function, who gives us a minimum in terms of number of cancer cells, with maximum in terms of cumulative treatment dosage.

A new single-phase power factor corrector (PFC) based on the Sheppard-Taylor topology is studied. Compared with conventional PFCs, this topology facilitates a better input current tracking, lower voltage stresses across the devices and larger output voltage range for the same operating area. The converter is integrated as a PFC at the DC-end of a single-phase diode bridge. Pulse-width-modulated (PWM) multi-loops control schemes are proposed and developed in order to ensure a unity power factor at the AC-source side and a regulated voltage at the DC-load side. The first control method uses the simple and robust hysteretic-based controller; the second employs a conventional PI regulator; and the third is based on the model nonlinearity compensation approach. The design of the last two control methods is based on the knowledge of a mathematical model that would accurately represent the converter. This model is developed in this paper using the state-space averaging technique, and then the small-signal transfer functions of the converter are derived for linear control design purpose. The performance of the different control strategies is evaluated through simulation experiments carried out on a numerical version of the converter. The implemented model of the converter is obtained by using the switching function technique. The control system is tested under both rated and disturbed operating conditions. The system performance is evaluated in terms of source current total harmonic distortion (THD), input power factor, DC voltage stabilization, and regulation following load variations.

International audience; We consider the problem of localising an unknown number of land mines usingconcentration information provided by a wireless sensor network. A number of vapoursensors/detectors, deployed in the region of interest, are able to detect the concentrationof the explosive vapours, emanating from buried land mines. The collected data iscommunicated to a fusion centre. Using a model for the transport of the explosive chemicalsin the air, we determine the unknown number of sources using a Principal ComponentAnalysis (PCA)-based technique. We also formulate the inverse problem of determiningthe positions and emission rates of the land mines using concentration measurementsprovided by the wireless sensor network. We present a solution for this problem basedon a probabilistic Bayesian technique using a Markov chain Monte Carlo sampling scheme,and we compare it to the least squares optimisation approach. Experiments conducted onsimulated data show the effectiveness of the proposed approach.

Capacitor banks are used to compensate the reactive power demand of large commercial and industrial loads. When used to switch capacitor banks mechanical breakers generate large current transients. These transients may cause serious system disturbances, premature wear of the breaker contacts and, possibly, shorten the life of the capacitors. While thyristor switches are not new and industry has successfully used them to obtain transient-free switching of capacitor banks, there are very few papers describing this application. This paper tries to fill the void and presents a comparative study of various three-phase configurations of semiconductor switches intended for low voltage (600 V and less) distribution systems. Simple theoretical analysis enables the calculation of the optimal switching times to minimize transients. These calculations take into account the system impedance and the initial capacitor voltages. >

Today the methods used by the medical team and occupational therapist are often qualitative. PLEIA software can be employed as a tool to evaluate the pointing user's capabilities. We proposed the new indexes to improve the classical evaluations methods that use the common factors as distance, time, errors and trajectory. The index command load shows the energy that the user employs to act on his technical aid. This energy could be not to be in direct relation with the efficiency, when the user realizes a task. PLEIA's capacities can be expanded as rehabilitation platform, telerehabilitation and experimentation platform for HCI systems with different haptic devices. The experiments are based on the real evaluation cases. In two cases, we evaluated the initial capabilities. The occupational therapist conclusions were: interface difficulties, some uncontrolled movements and the technical aid needs a best adaptation. The trajectories and indicators showed clearly this behavior. Claudia has a good interest with the exercises of PLEIA. The therapist detects that she has the same behavior as she rides her electric wheelchair. We start test PLEIA with the other modules in order to evaluate children with robots and wheelchair. In these modules, all indicators are included. We will compare evaluation tools.

Remote Laboratory Experimentation (RLE) is a technique used in modern engineering laboratories to help academic researchers and students perform laboratory experiments remotely through the internet. Due to the lack of well specified requirements for RLE, many RLE implementation models exist with different characteristics, using different technologies, and without a consistent set of services. In this work, the services provided by some recent RLE implementations models are identified, these services are analyzed, and specifications of a general improved model are concluded.

In this study, a two-stage DC-DC converter for high current applications is studied. The converter consists of two three-phase full-bridge inverters connected through three AC coupled inductors. A switching-functions-based model of the converter is first established, and then a control scheme is designed for both inverters in order to ensure a high power factor at the AC stage, and a regulated voltage at the DC load. The performance of the proposed control system is verified through numerical simulations. First, an ideal DC source is considered in order to test the performance of the control system, then a proton exchange membrane fuel cell is applied as the DC source in order to highlight the usefulness of this converter in such applications.

Power electronics building blocks (PEBBs)-based design methodology uses off the shelves components and improves scalability and modularity. These PEBB design's approaches need to be unified, approved and standardised. To reach these objectives, most of the research efforts are currently focusing on suggesting a universal control scheme. In fact, the control strategies presented up to date and their methods for generating signals to control power electronic switches are still customised and depend on the control algorithm or on the application. To overcome this issue, a universal strategy is suggested for a universal control protocol for PEBBs. It links the hardware layer to the application layer of the control function and it highly promotes interoperability. Additionally, the suggested interoperable method generates the appropriate control pulses for a wide range of application independently from the control algorithms.

This research work aims to optimize the operational procedure of cascade hydro plants in order to be efficiently used for power generation and irrigation. The challenge was to find the most realistic model based on the stochastic feature of water resources, on the power demand and on the irrigation profile. All these aspects are affected on the short and on the long run by a wide range of different conditions (hydrological, meteorological and hydraulic). During this project a bibliographic study was done in order to identify the technical issues that prevent the efficient use of hydro plants in developing countries. The system is numerically modelled taking into consideration all the variables and parameters involved in the optimal operation. The most appropriate approach is chosen in order to maximize the efficient use of water and to minimize economical losses, where different scenarios are simulated in order to validate the adopted suggestions., Ce travail de recherche vise à optimiser la procédure opérationnelle des centrales hydroélectriques en cascade afin de les utiliser efficacement pour la production d’électricité et l’irrigation. Le défi consistait à trouver le modèle le plus réaliste basé sur la caractéristique stochastique des ressources en eau, sur la demande en énergie et sur le profil d'irrigation. Tous ces aspects sont affectés à court et à long terme par un large éventail de conditions différentes (hydrologique, météorologique et hydraulique). Au cours de ce projet, une étude bibliographique a été réalisée afin d'identifier les problèmes techniques qui empêchent l'utilisation efficace des centrales hydroélectriques dans les pays en développement. Le système est modélisé numériquement en tenant compte de toutes les variables et paramètres impliqués dans le fonctionnement optimal. L'approche la plus appropriée est choisie afin de maximiser l'utilisation efficace de l'eau et de minimiser les pertes économiques, où différents scénarios sont simulés afin de valider les solutions adoptées.

Vehicular networks are the subject of active research in the field of networks as well as transport. The potential for vehicular networks to provide services such as traffic information in real time or accident makes this technology a very important research domain. These networks may support vehicle-to-vehicle communications (V2V), vehicle-to-infrastructure (V2I), or a combination of both. The IEEE 1609.4 is the specification of multichannel operations for IEEE802 .11p/WAVE vehicular networks (VANETs). It uses seven channels; one being a control channel (CCH) which is listened periodically by the vehicles and the other six channels are used as service channels (SCH). It also defines a time division between alternating CCH and SCH intervals. The purpose of this thesis is to evaluate the performance of VANETs in the case of vehicular communications without infrastructure, and at the lower layers of IEEE 802.11p standard. In the first part, we propose an opportunistic multichannel MAC allocation in an environment without infrastructure. This approach is consistent with the standard IEEE1609.4 -2010/WAVE for a multi-channel operation, and it is designed for data services applications (non-urgent), while ensuring the transmission of road safety messages and control packets. To maintain the quality of service of the two types of messages (urgent and non-urgent) by exploiting the channel capacity, two solutions are proposed. In the second part, when the vehicle selects its channel and controls its temporal alternation between CCH and SCH, it starts transmitting its packets, particularly on the CCH, which have an expiration time. We present an approach to minimize collisions between transmitters while avoiding contention at the beginning of CCH interval, especially in a context of high vehicular density. Although the mechanisms proposed above reduce the collision rate, it is not possible to completely remove these collisions. In the third part, we address the problem of collisions between broadcast packets on the CCH, especially when the load of transmitted messages exceeds the channel capacity. For this purpose, we propose a new analog network coding mechanism adapted to QPSK modulation for broadcast messages on the CCH. In this approach, known symbols are sent before sending the packets to estimate the channel parameters and an explicit solution is used to reverse the system of the superposition of two packets, Les réseaux véhiculaires font l’objet de recherches actives aussi bien dans le domaine des réseaux que dans celui des transports. Le potentiel des réseaux véhiculaires à fournir des services comme l’information sur le trafic en temps réel ou sur les accidents font de cette technologie un domaine de recherche très important. Ces réseaux peuvent comporter des communications véhicule-à-véhicule (V2V), véhicule-à-infrastructure (V2I), ou une combinaison des deux. La norme IEEE 1609.4 est la spécification multicanal pour l’IEEE802.11p/WAVE des réseaux véhiculaires (VANETs). Elle utilise sept canaux, l'un étant un canal de contrôle (CCH) qui est écouté par les équipements de façon périodique, et les six autres canaux sont utilisés comme canaux de service (SCH). Elle définit également une division du temps en alternance entre les intervalles CCH et les intervalles SCH. L’objet de cette thèse de doctorat est d’évaluer les performances des réseaux VANETs dans le cas des communications véhiculaires sans infrastructure, et au niveau des couches inférieures du standard 802.11p. Dans la première partie, nous proposons une approche MAC d’allocation multicanal opportuniste dans un contexte sans infrastructure. Cette approche est conforme à la norme IEEE1609.4 -2010 de l'architecture WAVE pour un fonctionnement multicanal, et elle est conçue pour des applications de services de données (non urgentes), tout en assurant la transmission des messages de sécurité routière et des paquets de contrôle. Pour maintenir la qualité de service des deux types de messages (urgents et non-urgents) en exploitant la capacité du canal, deux solutions sont proposées. Dans la deuxième partie, lorsque le véhicule sélectionne son canal et contrôle son alternance temporelle entre CCH et SCH, il commence à transmettre ses paquets, en particulier sur le canal CCH, lesquels ont une durée de péremption. Nous présentons une approche visant à minimiser les collisions des émetteurs tout en évitant la contention de début d’intervalle, en particulier dans un contexte de densité élevée de véhicules. Même si les mécanismes proposés ci-dessus diminuent le taux de collision, il n’est pas possible de les supprimer complètement. Dans la troisième partie, nous traitons le problème des collisions entre les paquets diffusés sur le CCH, en particulier quand la charge des messages transmis dépasse la capacité du canal. Pour cela, nous proposons un nouveau mécanisme de codage réseau analogique adapté à la modulation QPSK pour les messages diffusés sur le CCH. Dans cette approche des symboles connus sont envoyés avant d'envoyer les paquets pour estimer les paramètres du canal et une solution explicite est utilisée pour inverser le système de la superposition de deux paquets