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Identification of Hammerstein-Wiener model with discontinuous input nonlinearity

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Science China(Information Sciences) 2023年第12期66卷 33-47页

作者： A.BROURI F.Z.EL MANSOURI F.Z.CHAOUI C.ABDELAALI F.GIRI ENSAM Moulay Ismail University ENSAM University Mohammed V Normandie Universite

This paper deals with the identification of Hammerstein-Wiener models with an irregular function in the input block. These models comprise a set of linear segments. The linear time invariant(LTI) block may be parametric or nonparametric. The nonlinearity of the output can be any continuous function of arbitrary shape; it is not necessarily assumed to be invertible. Subsequently, sine inputs will be used to identify the system parameters. First, the output nonlinearity is determined by filtering the system output and varying the phase of a given reference sine signal; second, the parameters of the linear block can be determined for any frequency; and finally, the input nonlinearity can be obtained by changing the offset and amplitude of the input sine signal.

关键词： nonlinear systems nonlinear systems identification Hammerstein-Wiener models discontinuous nonlinearities hard nonlinearities

Liver trauma: What current management?

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Hepatobiliary & Pancreatic Diseases International 2018年第1期17卷 39-44页

作者： Mohamed Tarchouli Mohamed Elabsi Noureddine Njoumi Mohamed Essarghini Mahjoub Echarrab Mohamed Rachid Chkoff Department of Digestive Surgery Mohammed V Military Hospital Faculty of Medicine and Pharmacy Sidi Mohamed Ben Abdellah University Department of visceral Surgical Emergency Ibn Sina Hospital Faculty of Medicine and Pharmacy Mohammed V University Department of Digestive Surgery Mohammed V Military Hospital Faculty of Medicine and Pharmacy Mohammed V University

Background: The liver is the most commonly damaged organ in abdominal trauma. The management of liver trauma has experienced many changes over the last two decades. Currently there is a trend toward a non-operative treatment warranted by the successful pediatric experience and better results recorded in many trauma centers worldwide. This study aimed to evaluate outcomes of operative and non-operative management of liver trauma in our institution over the last five ***: The patients with a diagnosis of blunt or penetrating liver injuries, admitted and managed in our hospital from January 2012 to December 2016 were retrospectively studied. The patients were divided into 2 groups, operated and non-operated groups, according to the initial management considered appropriate at the time of patient admission. Clinical features and outcomes were ***: The study involved 83 patients, with a mean age of 33 years and a marked male predominance(85.5%). The most common type of lesions was blunt trauma and the main cause was road traffic accidents. Sixty-eight liver injuries(81.9%) were of low severity(grades Ⅰ,Ⅱ,Ⅲ), while 15(18.1%) were of high severity(grade Ⅳ or greater). Fifty-six patients(67.5%) had multiple injuries. Surgical treatment was performed in 26(31.3%) patients. Non-operative management was undertaken in 57 cases(68.7%). The morbidity and mortality rates were clearly lower in non-operative patients compared to those in the operated ***: Careful non-operative management is an adequate therapeutic strategy for the patients suffering from liver trauma with stable hemodynamics. Patients with complex hepatic trauma and especially those with other organ injuries continue to have significantly higher mortality.

关键词： Liver trauma Non-operative management Surgical treatment

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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas F.Sadreev Yong Li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.v.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Completed Tensor Product and Flatness

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Algebra Colloquium 2020年第3期27卷 599-606页

作者： Mohamed Tabaa Department of Mathematics Faculty of Sciences Mohammed v University in RabatMorocco

We give,in a more general case than the Noetherian case,an answer to the question posed by Shaul on the flatness of the completed tensor product.

关键词： preadic topology completed tensor product coherent ring flat module

Modelling and control of a grid-connected AC microgrid with the integration of an electric vehicle

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Clean Energy 2023年第4期7卷 707-720页

作者： Youssef Akarne Ahmed Essadki Tamou Nasser Hammadi Laghridat Higher National School of Arts and Crafts(ENSAM) Mohammed V UniversityRabatMorocco National High School for Computer Science and Systems Analysis(ENSIAS) Mohammed V UniversityRabatMorocco

The purpose of this paper is to propose an efficient model and a robust control that ensures good power quality for the AC microgrid(MG)connected to the utility grid with the integration of an electric vehicle(Ev).The MG consists of two renewable energy sources:a photovoltaic system(PvS)and a wind turbine system(WTS)based on a permanent magnet synchronous generator(PMSG),with the integration of an *** sources are used to supply active and reactive power to the AC bus and the utility *** power point tracking(MPPT)based on the perturb-and-observe(PO)method is used to increase the efficiency of the photovoltaic modules and improve overall *** MG system includes a 2-MW WTS,a 100-kW PvS and 12 kW provided by the *** validate the performance of the proposed system,a series of simulations were conducted using the MATLAB/Simulink?*** results demonstrate that the proposed system ensures high performance in terms of power quality,system stability,power tracking and safe integration of the Ev.

关键词： microgrid wind turbine system photovoltaic system electric vehicle grid-to-vehicle vehicle-to-grid control systems

Day-ahead seasonal solar radiation prediction,combining vMD and STACK algorithms

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Clean Energy 2023年第4期7卷 911-925页

作者： Saida El Bakali Ouadi Hamid Saad Gheouany ERERA National School of Arts and CraftsMohammed V UniversityRabatMorocco

This article proposes a method for accurately predicting solar irradiance over a 24-hour horizon to forecast photovoltaic energy generation in a positive-energy *** order to make this prediction,the input data are divided into seasons and preprocessed using the variational mode decomposition(seasonal-vMD)*** vMD method is used for extracting high-bandwidth features from the input data,decomposing them into a finite number of smooth modes and focusing on specific frequency ***,the accuracy of signal extraction using the vMD method can be improved by selecting particular parameters judiciously,which impacts the smoothing and frequency concentration of the extracted *** this regard,the salp swarm algorithm(SSA)is employed to identify the optimal vMD parameters that can be used to enhance extraction *** addition,the obtained residual between the observed solar irradiation data and their decomposed modes is treated to enhance the prediction process.A stacking algorithm(STACK)is used to predict the following 24-hour solar irradiance modes and the residual,which are finally summed to reconstruct the desired *** performances of the proposed prediction method are evaluated using two quantitative evaluation indices:the normalized root mean square percentage error(NRMSPE)and normalized mean absolute percentage error(NMAPE).The proposed model is trained on data collected for three years in Rabat(2019–22).The performance of the proposed model is evaluated by predicting the 24-hour solar irradiance for a different *** proposed approach seasonal-vMD-STACK is compared with two other methods in the case of using vMD-based STACK without season partition and STACK method ***,the proposed method has exhibited stability and proven good results with an NRMSPE of 3.87%and an NMAPE of 1.58%for cloudy days during the test *** results demonstrate that residual preprocessing,seasonal input data partition and appropriate selec

关键词： weather forecasting parametric optimization time series data preprocessing machine learning

Hybrid-integer algorithm for a multi-objective optimal home energy management system

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Clean Energy 2023年第2期7卷 375-388页

作者： Saad Gheouany Hamid Ouadi Saida El Bakali ERERA National School of Arts and CraftsMohammed V UniversityRabatMorocco

Most of the energy produced in the world is consumed by commercial and residential *** the growth in the global economy and world demographics,this energy demand has become increasingly *** has led to higher unit electricity prices,frequent stresses on the main electricity grid and carbon emissions due to inefficient energy *** paper presents an energy-consumption management system based on time-shifting of loads according to the dynamic day-ahead electricity *** simultaneously reduces the electricity bill and the peaks,while maintaining user comfort in terms of the operating waiting time of *** proposed optimization problem is formulated mathematically in terms of multi-objective integer non-linear programming,which involves constraints and consumer *** optimal scheduling,the management problem is solved using the hybridization of the particle swarm optimization algorithm and the branch-and-bound *** techniques are proposed to manage the trade-off between the conflicting *** first technique is the Pareto-optimal solutions classification using supervised learning *** second technique is called the lexicographic *** simulations were performed based on residential building energy consumption,time-of-use pricing(TOU)and critical peak pricing(CPP).The algorithms were implemented in *** results of the current work show that the proposed approach is effective and can reduce the electricity bill and the peak-to-average ratio(PAR)by 28% and 49.32%,respectively,for the TOU tariff rate,and 48.91% and 47.87% for the CPP tariff rate by taking into account the consumer’s comfort level.

关键词： home energy management system smart building coordination of home appliances metaheuristic algorithm day-ahead scheduling multi-objective binary non-linear constraint problem

Coordinated control by ADRC strategy for a wind farm based on SCIG considering low voltage ride-through capability

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Protection and Control of Modern Power Systems 2022年第1期7卷 82-99页

作者： Hammadi Laghridat Ahmed Essadki Tamou Nasser Higher National School of Arts and Crafts(ENSAM) Mohammed V UniversityRabatMorocco National High School for Computer Science and Systems Analysis(ENSIAS) Mohammed V UniversityRabatMorocco.

Wind farms are integrated with the power grid system to provide active and reactive *** in a wind farm,wind turbines(WTs)are highly coupled to their operating conditions,a central wind farm supervisory unit must take into account these conditions when producing power control references for each *** aim of this paper is to man-age and control the active and reactive power of wind farms based on squirrel cage induction generators and back-to-back *** proportional distribution algorithm is used for distributing wind farm power to individual *** addition,we consider the development of a local power management and control units for *** is in order to extract the maximum available power from the wind,and to provide the active and reactive power predetermined by the transmission system operator,or to satisfy the grid code requirements considering Low voltage Ride-through *** power dispatch strategy is to be used on all WTs using the distribution algorithm while ensuring the control loops using the proposed Active Disturbance Rejection Control *** results demonstrate that the proposed strategies are efficient and can guarantee the safe integration of wind farms into the grid while respecting grid code requirements and power system stability.

关键词： Wind farm Wind generator SCIG ADRC Supervision Control

On Crossed Product Algebras over Henselian valued Fields

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Algebra Colloquium 2020年第3期27卷 389-404页

作者： Driss Bennis Karim Mounirh Faculty of Sciences Research Center CeReMAR Mohammed V University in RabatRabatMorocco

Let D be a tame central division algebra over a Henselian valued field E,D be the residue division algebra of D,E be the residue field of E,and n be a positive *** prove that M_(n)(D)has a strictly maximal subfield which is Galois(resp.,abelian)over E if and only if M_(n)(D)has a strictly maximal subfield K which is Galois(resp.,abelian)and tame over E withГ_(K)■Г_(D),whereГ_(K)andГ_(D)are the value groups of K and D,*** partially generalizes the result proved by Hanke et *** 2016 for the case n=1.

关键词： (graded)Brauer group valued division algebras Henselization graded division algebras gauges