L’ANALYSE DU CYCLE DE VIE (ACV) D’UN BATIMENT DURABLE PAR L’ETUDE DU SYSTEME D’ISOLATION THERMIQUE : CAS D’UN BATIMENT DE BUREAUX DANS LA VILLE DE BISKRA, ALGERIE

La présente étude traite du cas d’un bâtiment de bureaux, situé dans la ville de Biskra (Algérie), caractérisée par un climat chaud et sec. Elle utilise  la méthode de l’analyse du cycle de vie(ACV) qui se déroule selon un protocole normalisé (normes ISO 14000 et 14040), favorisant une meilleure compréhension de l’incidence environnementale. Cette dernière  constitue une stratégie d’une politique internationale de protection de l’environnement et d’économie d’énergie. Ce travail est particulièrement dédié à l’évaluation de l’empreinte environnementale associée aux divers  matériaux de construction et des assemblages entrant dans les systèmes de bâtiment tels que : murs extérieurs, cloisons intérieures, planchers intermédiaires et planchers terrasses, menuiserie, etc.  Il s’appuie sur les bases de données Eco-Invent et sur le logiciel nova-EQUER qui est chainé aux applications de la simulation thermique dynamique (STD) du bâtiment par les logiciels Pleiades et Comfie. L’objectif est de fournir une aide à la décision pour la conception du bâtiment public, et de minimiser  les impacts sur l’environnement sans réduire le niveau de confort de ce dernier. Aussi, il est question de mettre en évidence l’influence significative du système d’isolation thermique, comme un choix technique parmi d'autres (matériaux, systèmes constructifs, choix architectural, isolation,  système de ventilation, chauffage, climatisation etc.….) sur les consommations énergétiques dans un bâtiment situé dans les régions arides à climat chaud et sec

Developing neural networks to investigate relationships between lighting quality and lighting glare indices

The present work compares the ability of the two most used glare indices, the Daylight Glare Probability (DGP) and the International Commission on Illumination (CIE) Glare Index (CGI), using Multiple Correspondence Analysis (MCA) and Artificial Neural Networks (ANN). The research investigates the efficiency of indexes in predictive indoor lighting quality. This study was carried out by analyzing data from a survey administered to ninety students in real design classrooms in the city of Biskra, Algeria. The experiment was conducted using three different lighting indoor conditions: natural and artificial lighting and mixed lighting. The true prediction of the Daylight Glare Probability for the variable Comfortable was 60.60%, and for (CIE) Glare Index the prediction values were equal to 44.60% for the same variable

Passive envelope design optimization of residential buildings using NSGA-II in different Algerian climatic zones

peer reviewedThe most sustainable building operation is that presents a minimum primary energy consumption, which minimizes the environmental impact. Therefore, the objective of this paper is to optimize the passive envelope design of the multi-family apartment building in Algeria for reducing heating and cooling energy consumption. 12 representative cities are investigated and 20 design variables with their different combinations are simulated. A multi-objective non-dominated sorting genetic algorithm (NSGA-II) is coupled with EnergyPlus building energy simulation software to obtain the optimal solution according to the Pareto approach. Our optimization approach achieved energy saving ranging from around 21% to 51%.nearly Zero Energy Buildings in Algeri

Towards a new model of light quality assessment based on occupant satisfaction and lighting glare indices

This study looks at the effect of daylighting on human performance. It includes a focus on glare index combined with the actual feeling of users of the classroom as a way to assess indoor lighting quality. The main objective of this research is to understand the impact of daylighting from windows on the glare sensation and also to determine which glare index is the closest to human visual sensation under local daylighting conditions in Biskra, Algeria with highly luminous climate. The study used High Dynamic Range (HDR) photography, Evaglare and Aftab Alpha software to calculate the two glare metrics Daylight Glare, Index (DGI) and the Daylight Glare Probability (DGP). A survey was also used with 90 occupants under different lighting conditions (different configurations) in a design classroom. In order to link the mathematical model and the human assessment of glare, statistical regression analysis was used. We established a statistically compelling connection between daylighting and student performance

Investigating the transient conditions of “Sabat” space and its influence on pedestrian sensations during thermal walks. Algiers’ Casbah case study

Cities are already witnessing the impacts of climate change. Prolonged heat exposure have a direct effect on pedestrians’ thermoregulatory system, causing serious heat-related issues in the form of fatigue and thermal exhaustion. While the human body is capable of maintaining heat balance, excessive heat exposure combined with increasing heat loads can deteriorate the thermoregulatory process which leads to discomfort. Walkability is one of the significant challenges for climate change mitigation. Balancing the dichotomy of walking to mitigate climate change, and mitigating climate change to walk emphasizes the importance of promoting resilient walkability. In this context, the term “resilience” is used to highlight the need to design urban spaces able to adapt to increased urban heat, enabling pedestrians to tolerate and recover from discomfort conditions. This study investigates the potential of the “Sabat”, a traditional semi-outdoor space with lift-up design, and its distribution in generating transient thermal aeraulic conditions, and reducing fatigue sensation, hence, supporting a positive walking experience. Thermal walks have been conducted in Casbah of Algiers during temperate and hot weather conditions, in the context of uphill walking. Results revealed the alliesthesial effect of cool-shaded and ventilated Sabats to reduce fatigue sensation, which was confirmed by the significant correlation at lag-(-1) (r = 0.504, p < 0.001). Findings shed light on the importance of maintaining dynamic alliesthesia to create modulated restorative opportunities and offer starting point for hypothesizing broader trends for future implementation of Sabat design in modern cities

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Etude de l’impact de la morphologie urbaine sur le confort thermique et la marchabilité dans les espaces publics extérieurs Cas de la ville de Sidi Okba

La morphologie urbaine doit soigneusement considérer l’aspect climatique de régions chaudes et arides ainsi que l’aspect comportemental des habitants. Pour traiter ce sujet de façon plus précise la présente recherche étudie l'impact de la morphologie urbaine sur le confort thermique extérieur et la marchabilité en comparant différents espaces publics situés dans la ville chaude et aride de Sidi Okba. Cette étude est de caractère multidisciplinaire, un ensemble d'approches méthodologiques qualitatives, quantitatives et numériques ont été utilisées. La méthode quantitative fait intervenir des mesures météorologiques sur le terrain qui ont été réalisées afin d'évaluer l'intensité de l'îlot de chaleur urbain dans les différentes configurations urbaines. En termes de marchabilité , le comportement de marche a été évalué sur la base d'une observation directe avec l'utilisation de l'instrument d'Audit de marchabilité. Pour l'approche numérique, afin de couvrir une large gamme de paramètres urbains, un modèle de simulation ENVI-met 04 a été utilisé pour décrire la distribution spatiale de la température moyenne radiante sur l'ensemble des espaces étudiés, ainsi que pour définir la zone de confort et les limites d'acceptabilité de l'indice de confort PET dans la ville chaude et aride de Sidi Okba. Concernant l'approche qualitative, une enquête par questionnaire s’est déroulée simultanément avec la compagne de mesures dans les différents espaces étudiés, cette démarche vise à vérifier l’impression immédiate des personnes face aux conditions thermiques extérieures pendant l'activité de marche. En plus, la technique de dérive photographique a été réalisée dans les différents espaces publics, cette technique vise à qualifier l'espace public et à analyser le lien indissociable entre « sentir et se mouvoir ». Les résultats montrent qu’un tissu avec une morphologie urbaine caractérisée par une forte densité de bâtiments, une diversité des fonctions et un haut niveau de connectivité entre les réseaux routiers est le meilleur pour le confort thermique extérieur et l'activité de marche. En terme de confort thermique à un micro échelle, la forte densité du bâti permet d’engendrer une géométrie compacte, et offrant un environnement protégé contre les rayons solaires directs, ce qui permet de diminuer sensiblement les valeurs de la température moyenne radiant et de la température d'air, et par conséquent contribue au confort thermique humain lors de la pratique de l’activité de marche en période estivale. En terme de marchabilité, un tissu dense avec une forte présence de végétation affect positivement la perception des gens, car elle permet de créer des milieux de vie respectueuse de l’échelle humaine et d’encadrer harmonieusement l’espace public, ce qui produit une sensation confortable et encourage les piétons à continuer de marcher le long de l'espace public. Cette étude permet également de mettre l'accent sur les critères physiques qui se trouvent dans le rouge (les points faibles). Si on est dans l'optique d'une amélioration, cela permet d'agir concrètement sur quel type d’intervention urbaine on met en place chaque espace étudié

The Ksour of the SAHARA Desert as A Great Lesson of Sustainable Urban Design in Hot Desert Oases

Despite the severity of the SAHARA Desert from many aspects, the man was able to confront it, and to build great human&nbsp; settlements distributed in different areas as the REG of Mzab Valley, the ERG of Righ Valley, Hoggar Mountains ... And many others points to human life.These Settlements called SAHARAN Ksour, which become today a valuable architectural and urban heritage. This paper presents a thorough study on SAHARAN Ksour from an environmental point of view, so we focused on its adaptation with the different environmental elements, and speaks about the most important components of architectural and urban design as: The internalization concept. Half-covered street system. Twisted street design. And the use of the palm grove as a climatic component of urban and architectural design. And how to deal with environmental variables such as warm winds (Sirocco), sandy spring wind, high temperatureand the seriously low humidity, all these elements, components and relations are presented in this paper in manyexamples of Ksour situated in Algerian SAHARA. This paper is a lesson between environmental components and SAHARA desert urban heritage, which we aim to give prominence to the ability of the past SAHARAN human settlements to challenge the desert at the time where present ones can't challenge it, all this to find a formula for the future SAHARA desert sustainable architectural and urban design

A CFD Comsol model for simulating complex urban flow

International audienc