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In this paper, hybridization is proposed as an alternative approach to sustainable tourism development in Morocco’s southeastern cities. Hybridization refers to the integration of multiple elements, such as traditional and modern, to create a new synthesis that incorporates the aspects required from a modern building. The evolutionary approach adopted helps to balance between short-term requirements and long-term sustainability, while also preserving cultural heritage and promoting innovation. By implementing sustainable and culturally sensitive strategies, a positive future can be secured for architectural and urban systems like Ksours and Kasbahs.

A simple, yet complete framework is introduced with the aim or modelling gram breakage in sous and crusnabie granular materials. The evolution of grain breakage is measured using a specific parameter of the grain-size distribution. The evolution of this new breakage parameter is related to the applied mechanical work, which allows the predictions to be independent of the stress paths. The correlation function proposed is trilinear, and is capable of describing the initiation, development, and stabilization of breakage. The initial state, coupled with three additional parameters, is used to calibrate this function. The three parameters are related to a grain specific quantity representing the strength of the particles that form the granular medium. The theory of fractal fragmentation is adopted, and the final state is considered to be unique and described by a single parameter: the fractal dimension. When tested against experimental results, this model was able to correctly predict the crushable behavior of a sand. Key words: particle breakage, granular media, grain crushing, fractal, particle strength, grain size distribution. Un cadre mecanique a la fois simple et complet est introduit dans le but de modeliser la rupture des grains dans les sols et autres milieux granulaires broyables. L'evolution de la rupture des grains est mesuree en utilisant un parametre caracteristique de la distribution granulometrique. L'evolution de ce nouveau parametre de rupture est reliee au travail mecanique applique, ce qui rend les predictions independantes du chemin des contraintes. La fonction de correlation proposee est trilineaire, et donc capable de decrire l'initiation, le developpement et la stabilisation de la rupture. L'etat initialainsi que trois autres parametres servent a calibrer cette fonction. Les trois parametres sont relies a une quantite propre au grain, et qui represente la resistance des particules qui forment le milieu granulaire. La theorie de la fragmentation fractale est adoptee, et l'etat final est donc suppose comme etant unique, et decrit par un seul parametre : la dimension fractale. Lorsque le modele est teste et les resultats compares a des travaux experimentaux, il devient possible d'apprecier la capacite du modele a simuler le comportement d'un sable. Mots-cles: rupture des particules, milieu granulaire, broyage des grains, fractal, resistance des particules, distribution granulometrique., Introduction Granular materials are of particular interest for civil engineers and soil mechanics specialists. Over time, the integrity of these materials varies depending on the mechanical conditions, the nature of [...]

We are grateful for the interest in our paper (Konrad and Salami 2018). The discussers reviewed the conceptual model for particle breakage in granular materials, and proposed ways to improve [...]

The recently developed framework for modeling grain breakage in granular materials is shown to be valid for saturated/unsaturated conditions. The model describes the initiation, development, and stabilization of breakage using three parameters, all depending on the strength of a representative particle size. When water is introduced, the strength of the soil's particles is expected to weaken, which leads to increased breakage intensities. The model is able to predict the early onset of crushing and the increase in particle breakage rate, both considered characteristic behaviors of a crushable granular medium in wet conditions. Initially dry and saturated model lines limit the evolution of the model parameters in the intermediate saturation states. A mid-loading change in the saturation of the granular medium results in an increased rate of particle breakage. The experimental data available in the literature is analyzed in light of the proposed model, which allows a better understanding of the development of particle breakage under the influence of water. [ABSTRACT FROM AUTHOR]

This paper presents the development of a Class-D full-bridge zero-voltage switching (ZVS) inverter, applicable to wireless power transfer (WPT) systems, operating at 13.56 MHz switching frequency with dynamic dead-time control (DDTC). Resonant-coupled WPT systems are being designed at ultrahigh switching frequencies to reduce the size of the wireless link and the passive components. Maintaining ZVS while controlling the output power delivered to a fixed or variable load is one of the major challenges of designing inverters at multi-MHz switching frequencies. DDTC is the approach deployed in this paper to sustain soft switching of a Class-D full-bridge inverter over the full range of output power while regulating the input dc bus voltage. Simulation results are presented to show that dynamically controlling the dead-time during input dc bus voltage variations reduces switch-node voltage overshoot, prevents large current spikes in the switching devices, and reduces associated high switching loss. Practical results obtained show that DDTC reduces switch-node voltage overshoot, increases the inverter efficiency, and reduces the steady-state temperature of the inverter during output power regulation. [ABSTRACT FROM AUTHOR]

In soil mechanics, the material behaviour is significantly affected by grain crushing. This energy dissipating mechanism, along with the frictional rearrangement of grains, is responsible for the energy loss associated with plasticity. However, the micromechanical factors at the grain scale have not been studied by constitutive models which tend to focus on macroscopic parameters. In this study, the influence of the coordination number on the fragmentation of a single cylindrical grain specimen has been examined with a new device by which a series of multipoint crushing tests has been conducted. Experiments conducted with this device have shown the importance of the contacts number, position, type and force in the fragmentation of the individual grain. The results, analysed by imaging techniques, demonstrate that the existing models treating grain rupture are indeed incapable of reproducing the observed fragmentation. Two types of cracks were distinguished, each corresponding to a different crack mode, depending on the contact arrangement. The results of this study could be integrated into fragmentation models for predicting the occurrence of cracks, and the shape of the resulting fragments. [ABSTRACT FROM AUTHOR]

This study discusses the connection of wind farms (WFs) to power system through unified inter-phase power controller (UIPC) for enhanced transient stability of the power system. The power circuit of the UIPC is based on the conventional inter-phase power controller (IPC), which its phase-shifting transforms are substituted by two series converters and one shunt converter. During fault condition, the WF connected through UIPC acts as STATCOM with capability of the active and reactive power control at UIPC connecting point. Based on the UIPC model and low-voltage ride-through requirements of the new grid codes, a control system for active and reactive powers control is proposed for enhancement transient stability of power system. The proposed approach is validated in a four-machine two-area test system. Power systems computer aided design (PSCAD)/EMTDC simulation results demonstrate that the UIPC provides an effective solution for enhancement of transient stability of power system including WFs. [ABSTRACT FROM AUTHOR]