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How complex is the structure of quantum geometry? In several approaches, the spacetime atoms are obtained by the SU(2) intertwiner called quantum tetrahedron. The complexity of this construction has a concrete consequence in recent efforts to simulate such models and toward experimental demonstrations of quantum gravity effects. There are, therefore, both a computational and an experimental complexity inherent to this class of models. In this paper, we study this complexity under the lens of stabilizer entropy (SE). We calculate the SE of the gauge-invariant basis states and its average in the SU(2) gauge invariant subspace. We find that the states of definite volume are singled out by the (near) maximal SE and give precise bounds to the verification protocols for experimental demonstrations on available quantum computers., Comment: 8 pages, 3 figures, 9 pages supplementary material

We employ the Stabilizer Renyi Entropy (SRE) to characterize a quantum phase transition that has so far eluded any standard description and can thus now be explained in terms of the interplay between its non-stabilizer properties and entanglement. The transition under consideration separates a region with a unique ground state from one with a degenerate ground state manifold spanned by states with finite and opposite (intensive) momenta. We show that SRE has a jump at the crossing points, while the entanglement entropy remains continuous. Moreover, by leveraging on a Clifford circuit mapping, we connect the observed jump in SRE to that occurring between standard and generalized $W$-states with finite momenta. This mapping allows us to quantify the SRE discontinuity analytically., Comment: 8 pages including supplementary material, 3 figures

We study the interplay between magic and entanglement in quantum many-body systems. We show that non-local magic, which is supported by the quantum correlations is lower bounded by the non-flatness of entanglement spectrum and upper bounded by the amount of entanglement in the system. We then argue that a smoothed version of non-local magic bounds the hardness of classical simulations for incompressible states. In conformal field theories, we conjecture that the non-local magic should scale linearly with entanglement entropy but sublinearly when an approximation of the state is allowed. We support the conjectures using both analytical arguments based on unitary distillation and numerical data from an Ising CFT. If the CFT has a holographic dual, then we prove that the non-local magic vanishes if and only if there is no gravitational back-reaction. Furthermore, we show that non-local magic is approximately equal to the rate of change of the minimal surface area in response to the change of cosmic brane tension in the bulk., Comment: 62 pages, 20 figures; title changed, Theorem 1 and 2 refined, references added

Magic states are the resource that allows quantum computers to attain an advantage over classical computers. This resource consists in the deviation from a property called stabilizerness which in turn implies that stabilizer circuits can be efficiently simulated on a classical computer. Without magic, no quantum computer can do anything that a classical computer cannot do. Given the importance of magic for quantum computation, it would be useful to have a method for measuring the amount of magic in a quantum state. In this work, we propose and experimentally demonstrate a protocol for measuring magic based on randomized measurements. Our experiments are carried out on two IBM Quantum Falcon processors. This protocol can provide a characterization of the effectiveness of a quantum hardware in producing states that cannot be effectively simulated on a classical computer. We show how from these measurements one can construct realistic noise models affecting the hardware.

The State plays an important role in society to the point of having for a long time the monopoly of the management of public affairs. The diversity of its field of intervention and the complexity of the management of public services bring in overtime other actors, including the private sector. In this context, several countries have opted for the policy of public-private partnerships in order to boost economic development. Public-Private Partnerships have been tested in both developed and developing countries for one purpose, which is better management of the public service through collaboration between the public sector and the private sector, this type of partnership is also the result of recommendations made by international organizations as the OECD and the World Bank. The objective of our article is to study and understand PPPs as a development phenomenon through a comparative study between the two PPP models in Morocco and France. In addition, we highlight the importance of the legal and institutional framework for PPPs which can be adapted according to the national context of each country in order to promote the development of these types of partnership.   Keywords:  Public Private Partnership, Private Sector, Public Sector, Comparative Study. JEL Classification: P51, P41. Paper type: Theoretical Research&nbsp, L’État joue un rôle prépondérant dans la société au point d’avoir pendant longtemps le monopole de la gestion de la chose publique. La diversité de son domaine d’intervention et la complexité de la gestion des services publics font intervenir avec le temps d’autres acteurs dont le secteur privé. Dans ce titre, plusieurs pays ont opté pour la politique des Partenariats public-privé afin de booster le développement économique et surmonter les contraintes des finances publiques dont souffrent la plupart de ces États. Les Partenariats Public-Privé ont été expérimentés aussi bien dans les pays développés que dans les pays en développe pour une seule fin qui est une meilleure gestion du service public à travers une collaboration entre le secteur public et le secteur privé, ce type de partenariat est également le résultat des recommandations faites par les organismes internationaux tels que l’OCDE et la Banque mondiale. L’objectif de notre article est d’étudier et comprendre les PPP comme phénomène de développement à travers une étude comparative entre les deux modèles de PPP au Maroc et en France. Nous mettons en évidence l’importance du cadre juridique et institutionnel des PPP qui peuvent être adaptés selon le contexte national de chaque pays afin de favoriser le développement de ces types de partenariat.   Mots-clés : Partenariat Public Privé, Secteur Privé, Secteur Public, Étude comparative. Classification JEL : P51, P41. Type de l’article : Article théorique. &nbsp

Observable scattering processes entail emission-absorption of soft photons. As these degrees of freedom go undetected, some information is lost. Whether some of this information can be recovered in the observation of the hard photons, depends of the actual pattern of the scrambling of information. We compute the information scrambling of photon scattering by the tripartite mutual information in terms of the 2-Renyi entropy, and find a finite amount of scrambling is present. The developed procedure thus sheds novel light on the black hole information loss paradox, showing that scrambling is a byproduct of decoherence achieved by the scattering system in its interaction with the environment, due to the emission-absorption of soft photons in fully unitary processes., Comment: 23 pages, 4 figures

Black holes are a recently observed theoretical prediction of General Relativity, characterized by event horizons, from which information cannot escape. Examined through the lenses of quantum mechanics, they can radiate at a definite temperature inverse to their mass and horizon radius. Hawking radiation, whose spectrum was calculated considering particles scattering off black holes, is connected to the paradox of the loss of information falling into them. Information can become non-fungible, due to scrambling. We demonstrate this feature not to be restricted to curved space-times: soft radiation scattering in a flat space-time does scramble information as well. To this end, we compute the scrambling of information through the tripartite mutual information in a scattering process off a black hole and compare it with the flat space-time analog. We show that the scrambling power of the gravitational field of a black hole is negligible with respect to the scrambling power of flat space-time., Comment: 90 pages

Traditionally, the production efficiency of a factory floor is evaluated using non-real time objective functions. These are based on scheduling punctuality criteria such as 'earliness (a measure of finishing operations ahead of schedule)' and 'tardiness (a measure of delay in executing certain operations)'. With process automation becoming more and more inevitable due to the emergence of Industry 4.0 / Industry 5.0, real-time objective functions are also gaining popularity. One such criterion is 'synchronization' or 'timing'. In this article, an IoT enabled real-time synchronization approach is presented in the context of Integrated Industrial Internet of Things (IIoT) from a service provider's perspective. A new business and operational model, termed as "Timing-As-A-Service (TAAS)", is introduced. In this model, the role of a service provider is to "supply" synchronization from the mobile networks to the IIoT domain., Comment: 7 pages

Quantum information scrambling is a unitary process that destroys local correlations and spreads information throughout the system, effectively hiding it in nonlocal degrees of freedom. In principle, unscrambling this information is possible with perfect knowledge of the unitary dynamics [B. Yoshida and A. Kitaev, arXiv:1710.03363.]. However, this Letter demonstrates that even without previous knowledge of the internal dynamics, information can be efficiently decoded from an unknown scrambler by monitoring the outgoing information of a local subsystem. Surprisingly, we show that scramblers with unknown internal dynamics, which are rapidly mixing but not fully chaotic, can be decoded using Clifford decoders. The essential properties of a scrambling unitary can be efficiently recovered, even if the process is exponentially complex. Specifically, we establish that a unitary operator composed of $t$ non-Clifford gates admits a Clifford decoder up to $t\le n$.

Background: Dry spells are serious obstacles to rainfed agriculture in Sahelian countries. Various water harvesting techniques are used by farmers to reduce the impact of climate variability, but are not sufficient in the case of a prolonged drought lasting 2–3 weeks. The farmers believe supplemental irrigation is a good way to adapt rainfed agriculture to dry spells. In this study, we evaluated the food contribution and profitability of supplemental irrigation of rainfed crops comparing various farm ponds that collect runoff water from the surrounding landscape. Methods: We analyzed the contribution of supplemental irrigation to food security and compared the profitability of different types of ponds constructed by farmers in northern Burkina Faso. Human cereal requirement was used as indicators to analyze the contribution of supplemental irrigation to food security. The criteria for analyzing the profitability of the selected ponds were gross margin (GM), net present value (NPV), internal rate of return (IRR) and payback period (PBP). Results: Our results show that the additional yield of corn obtained with supplemental irrigation makes it possible to meet the monthly cereal needs of at least 17 people and generates an additional GM of FCFA 178,483 (US$ 309.26) compared to no irrigation. The estimate of the NPV, from IRR and PBP showed that the profitability of supplemental irrigation in 15 agricultural seasons varies between the type of ponds constructed. Conclusions: Given the up-front cost and the farmers' lack of resources, the ponds require a subsidy or a credit policy to facilitate the adoption of supplemental irrigation in Sahelian countries. However, the irrigation strategies to optimize agricultural income remain a field of research to be explored.

In conditional automation, a response from the driver is expected when a take over request is issued due to unexpected events, emergencies, or reaching the operational design domain boundaries. Cooperation between the automated driving system and the driver can help to guarantee a safe and pleasant transfer if the driver is guided through a haptic guidance system that applies a slight counter-steering force to the steering wheel. We examine in this work the impact of haptic guidance systems on driving performance after a take over request was triggered to avoid sudden obstacles on the road. We studied different driver conditions that involved Non-Driving Related Tasks (NRDT). Results showed that haptic guidance systems increased road safety by reducing the lateral error, the distance and reaction time to a sudden obstacle and the number of collisions.

In this paper, we show how the restriction of the Quantum Geometric Tensor to manifolds of states that can be generated through local interactions provides a new tool to understand the consequences of locality in physics. After a review of a first result in this context, consisting in a geometric out-of-equilibrium extension of the quantum phase transitions, we argue the opportunity and the usefulness to exploit the Quantum Geometric Tensor to geometrize quantum chaos and complexity., Comment: Conference paper

In this paper, we show how the restriction of the Quantum Geometric Tensor to manifolds of states that can be generated through local interactions provides a new tool to understand the consequences of locality in physics. After a review of a first result in this context, consisting in a geometric out-of-equilibrium extension of the quantum phase transitions, we argue the opportunity and the usefulness to exploit the Quantum Geometric Tensor to geometrize quantum chaos and complexity., Comment: Conference paper

Purpose The construction industry represents most of every country’s finances and vital to continued economic growth and activities, especially in developing countries. The impact of the severe acute respiratory syndrome-2 disease (COVID19) on the government’s income resulted in the expectation of many public projects being cancelled or delayed providing little opportunity for the emergence of new public projects. This study collated a global qualitative perspective (survey interviews) on the lessons learned during the COVID-19 pandemic and the positive and negative impacts for future-proofing the construction sector. Design/methodology/approach In total, 76 respondents from five continents excluding South America responded to the online open-ended structured questionnaire. Data collected were analysed through artificial inteligence analytics tool – Zoho analytics. Findings The themes indicating the positive impact obtained from the interview were overhead cost reduction, remote working environment, focus on health and safety, improved productivity and sustainability goals while the themes signifying the negative impact were low business turnover, delays in construction payment and output, difficulties working from home and job losses. Supply chain management, construction project management improvement, concentration on health and safety and effective virtual working environment were collated as themes on lessons learned. Social implications The major findings of this study emphasise on the need to improve the occupational health and safety and onsite safety measures for future proofing of the construction industry. Originality/value The findings from the analyses made clear the imperativeness of the built environment research, with a focus on novel framework and strategies for future proofing the construction industry.

The purpose of this study is to investigate and analyze how organizational members experience the organizational culture of companies that claim to have diversity among employees. A qualitative research method was used in the study, where the empirical data was collected through semi-structured interviews. The interview questions are based on the study's chosen theory and a total of 10 interviews were conducted. The empirical data was analyzed with the chosen theory to be able to answer the research question. Broadly speaking, companies' organizational cultures are experienced as inclusive by employees. They feel that they need each other because they work together. However, there is a lack of trust between several employees, which may be due to too weak relationships. Not all employees agree on whether the companies have a diversity identity, but that it needs to be managed to a greater extent. Employees feel that there is potential in the development of diversity management, by including more people with other differences, especially among managers and recruiters. Employees feel recognized, where open communication plays an important role. Not all members of the organization agree on the companies' most important values, and many employees feel that they have no influence over them. Employees also emphasize the importance of individuals' impact on opportunities and convenience, which can affect their motivation., Syftet med denna studie är att undersöka och analysera hur organisationsmedlemmar upplever organisationskulturen på företag som påstår sig ha mångfald bland anställda. I denna studie genomfördes det en kvalitativ forskningsmetod där empirin samlades in genom semistrukturerade intervjuer. Intervjufrågorna grundar sig utifrån studiens valda teori och totalt genomfördes 10 intervjuer. Empirin analyserades med den valda teorin för att kunna besvara forskningsfrågan. I stora drag upplevs företagens organisationskulturer inkluderande av anställda. De upplever att de behöver varandra eftersom de samarbetar. Dock upplevs det en bristande tillit mellan flertalet anställda, vilket kan bero på för svaga relationer. Alla anställda är inte eniga om företagen har en mångfaldsidentitet, men att den behöver hanteras i större utsträckning. Anställda upplever att det finns potentialer i utvecklingen av mångfaldshantering, i form av inkludering av fler personer med andra skillnader, speciellt bland chefer och rekryterare. Anställda känner sig erkända, där öppen kommunikation spelar en viktig roll. Alla organisationsmedlemmar är även inte eniga om företagens viktigaste värderingar, och flertalet anställda upplever att de inte har något inflytande av de. Anställda framhäver även vikten av enskilda individers påverkan av möjligheter och bekvämlighet, vilket kan påverka deras motivation.

To validate the safety of automated vehicles (AV), scenario-based testing aims to systematically describe driving scenarios an AV might encounter. In this process, continuous inputs such as velocities result in an infinite number of possible variations of a scenario. Thus, metamodels are used to perform analyses or to select specific variations for examination. However, despite the safety criticality of AV testing, metamodels are usually seen as a part of an overall approach, and their predictions are not questioned. This paper analyzes the predictive performance of Gaussian processes (GP), deep Gaussian processes, extra-trees, and Bayesian neural networks (BNN), considering four scenarios with 5 to 20 inputs. Building on this, an iterative approach is introduced and evaluated, which allows to efficiently select test cases for common analysis tasks. The results show that regarding predictive performance, the appropriate selection of test cases is more important than the choice of metamodels. However, the choice of metamodels remains crucial: Their great flexibility allows BNNs to benefit from large amounts of data and to model even the most complex scenarios. In contrast, less flexible models like GPs convince with higher reliability. Hence, relevant test cases are best explored using scalable virtual test setups and flexible models. Subsequently, more realistic test setups and more reliable models can be used for targeted testing and validation., Comment: 10 pages, 14 figures, 1 table, associated dataset at https://github.com/wnklmx/DSIOD

The purpose of this study is to investigate and analyze how organizational members experience the organizational culture of companies that claim to have diversity among employees. A qualitative research method was used in the study, where the empirical data was collected through semi-structured interviews. The interview questions are based on the study's chosen theory and a total of 10 interviews were conducted. The empirical data was analyzed with the chosen theory to be able to answer the research question. Broadly speaking, companies' organizational cultures are experienced as inclusive by employees. They feel that they need each other because they work together. However, there is a lack of trust between several employees, which may be due to too weak relationships. Not all employees agree on whether the companies have a diversity identity, but that it needs to be managed to a greater extent. Employees feel that there is potential in the development of diversity management, by including more people with other differences, especially among managers and recruiters. Employees feel recognized, where open communication plays an important role. Not all members of the organization agree on the companies' most important values, and many employees feel that they have no influence over them. Employees also emphasize the importance of individuals' impact on opportunities and convenience, which can affect their motivation., Syftet med denna studie är att undersöka och analysera hur organisationsmedlemmar upplever organisationskulturen på företag som påstår sig ha mångfald bland anställda. I denna studie genomfördes det en kvalitativ forskningsmetod där empirin samlades in genom semistrukturerade intervjuer. Intervjufrågorna grundar sig utifrån studiens valda teori och totalt genomfördes 10 intervjuer. Empirin analyserades med den valda teorin för att kunna besvara forskningsfrågan. I stora drag upplevs företagens organisationskulturer inkluderande av anställda. De upplever att de behöver varandra eftersom de samarbetar. Dock upplevs det en bristande tillit mellan flertalet anställda, vilket kan bero på för svaga relationer. Alla anställda är inte eniga om företagen har en mångfaldsidentitet, men att den behöver hanteras i större utsträckning. Anställda upplever att det finns potentialer i utvecklingen av mångfaldshantering, i form av inkludering av fler personer med andra skillnader, speciellt bland chefer och rekryterare. Anställda känner sig erkända, där öppen kommunikation spelar en viktig roll. Alla organisationsmedlemmar är även inte eniga om företagens viktigaste värderingar, och flertalet anställda upplever att de inte har något inflytande av de. Anställda framhäver även vikten av enskilda individers påverkan av möjligheter och bekvämlighet, vilket kan påverka deras motivation.

Recent developments in advanced driving assistance systems (ADAS) that rely on some level of autonomy have led the automobile industry and research community to investigate the impact they might have on driving performance. However, most of the research performed so far is based on simulated environments. In this study, we investigated the behavior of drivers in a vehicle with automated driving system (ADS) capabilities in a real-life driving scenario. We analyzed their response to a take over request (TOR) at two different driving speeds while being engaged in non-driving-related tasks (NDRT). Results from the performed experiments showed that driver reaction time to a TOR, gaze behavior and self-reported trust in automation were affected by the type of NDRT being concurrently performed and driver reaction time and gaze behavior additionally depended on the driving or vehicle speed at the time of TOR., Comment: Submitted and accepted in the IEEE Intelligent Vehicle Symposium 2021 Conference (IV2021)

Cotula cinerea is a traditional Algerian medicinal plant that has many biological properties, such as analgesic, antiseptic and antibacterial activities. Essential oil of Cotula cinerea was subjected to chromatographical and spectroscopical studies to determine the chemical composition. The analysis highlighted that the oil contains trans thujone (51.86%), santalina triéne (10.6%), α-pinéne (2.02%), sabinene (6.17%), cineole <1.8> (5.34%), δ-terpinene (1.57%), camphor (2.63%), β-terpineol (1.39 %) and terpin-4-ol (1.73%) as the major constituents. The essential oil was tested for antibacterial activity. The oil exhibited substantial antibacterial activity against both the tested Gram negative and Gram positive bacteria. In search of better anticancer agent the essential oil of Cotula cinerea was also subjected for in-vitro cytotoxic activity on two cancerous human cell lines; colon (HCT116) and hepatic (HePG2) cancer cell lines. The results indicates that the essential oil of Cotula cinerea has a significant cytotoxic activity on the tested colon cancer cell lines with a 66.9% inhibition and a minimal inhibition (33.9%) on liver cancer cell line.

Concrete in sulphates environments often undergoes significant alterations that often have significant adverse results on its engineering properties. However, the choice of cement type is a very important factor for concrete exposed in aggressive environment. This research presents the effect of two types of cement on the mechanical and microstructure properties of ordinary concretes exposed in aggressive solution dosed with 5% of gypsum (Ca2SO4.2H2O). The tests studied in this experimental part were the compressive strength, flexural strength, thermogravimetry, mercury intrusion porosimetry and mass variations of the concrete. The results clearly show that the CEM I 42.5 is suitable for the formulation of concretes exposed to sulphate attack and their properties are better compared with the CEM II/A 42.5.

Concrete in sulphates environments often undergoes significant alterations that often have significant adverse results on its engineering properties. However, the choice of cement type is a very important factor for concrete exposed in aggressive environment. This research presents the effect of two types of cement on the mechanical and microstructure properties of ordinary concretes exposed in aggressive solution dosed with 5% of gypsum (Ca2SO4.2H2O). The tests studied in this experimental part were the compressive strength, flexural strength, thermogravimetry, mercury intrusion porosimetry and mass variations of the concrete. The results clearly show that the CEM I 42.5 is suitable for the formulation of concretes exposed to sulphate attack and their properties are better compared with the CEM II/A 42.5.

The manifold of ground states of a family of quantum Hamiltonians can be endowed with a quantum geometric tensor whose singularities signal quantum phase transitions and give a general way to define quantum phases. In this paper, we show that the same information-theoretic and geometrical approach can be used to describe the geometry of quantum states away from equilibrium. We construct the quantum geometric tensor $Q_{\mu\nu}$ for ensembles of states that evolve in time and study its phase diagram and equilibration properties. If the initial ensemble is the manifold of ground states, we show that the phase diagram is conserved, that the geometric tensor equilibrates after a quantum quench, and that its time behavior is governed by out-of-time-order commutators (OTOCs). We finally demonstrate our results in the exactly solvable Cluster-XY model.

Using a generalized translation operator, we obtain an analog of Younis' theorem [Theorem 5.2, Younis M.S. Fourier transforms of Dini–Lipschitz functions, Int. J. Math. Math. Sci., 1986] for the Jacobi transform for functions from the (ν,γ,p)-Jacobi–Lipschitz class in the space Lp(R+,Δ(α,β)(t)dt).

The manifold of ground states of a family of quantum Hamiltonians can be endowed with a quantum geometric tensor whose singularities signal quantum phase transitions and give a general way to define quantum phases. In this paper, we show that the same information-theoretic and geometrical approach can be used to describe the geometry of quantum states away from equilibrium. We construct the quantum geometric tensor $Q_{\mu\nu}$ for ensembles of states that evolve in time and study its phase diagram and equilibration properties. If the initial ensemble is the manifold of ground states, we show that the phase diagram is conserved, that the geometric tensor equilibrates after a quantum quench, and that its time behavior is governed by out-of-time-order commutators (OTOCs). We finally demonstrate our results in the exactly solvable Cluster-XY model.

Description du sujet. Dans les pays sahéliens, la répartition spatio-temporelle hautement variable des précipitations demeure une menace pour l'agriculture pluviale, malgré le grand nombre de techniques diffusées pour la conservation des eaux et des sols. Objectifs. Analyser plusieurs stratégies d'irrigation des cultures pluviales et évaluer l'impact probable des mesures économiques incitatives en vue de faciliter l'adoption de l'irrigation de complément à partir des petits bassins individuels de collecte des eaux de ruissellement face aux poches de sècheresse. Méthode. Les stratégies possibles d'irrigation de complément et les simulations des mesures économiques incitatives ont été analysées à partir d'un modèle bio-économique appliqué à une exploitation agricole type. Résultats. Les simulations montrent que l'irrigation de complément permet d'accroitre le revenu espéré des agriculteurs, comparativement à la situation sans irrigation. La culture du maïs, du sorgho et du mil sous l'irrigation de complément en année sèche augmente le revenu espéré de 26,49 % (133 030 francs CFA, équivalent à 202,80 euros) comparativement à la situation sans irrigation. Les simulations visant à promouvoir l'irrigation de complément à partir des petits bassins individuels sont axées sur quatre modalités de subventions et un système d'octroi de crédit aux ménages agricoles. Conclusions. Parmi les mesures incitatives, la subvention sous forme de travail contre nourriture pour mobiliser la main-d'oeuvre en vue de construire les bassins semble particulièrement adaptée pour la mise à l'échelle de la pratique de l'irrigation de complément à partir des petits bassins individuels.

Tlemcen is a city of art and history, which was built in Roman times. It was architecturally enriched over time with stylistic contributions of different dynasties. This city was ranked saved area in 2009 by executive decree. The geographical trace of this area affects only the Islamic medina Tagrart excluding the rest of the city. Therefore, we wondered about the real limits of this millenary city. For that, we traced its urban heritage by studying the stratification and characteristics of the urban fabric. This new geographical trace demonstrates the exclusion of many historic areas of the heritage classification., Tlemcen est une ville d’art et d’histoire qui a été édifiée á l’époque romaine. Elle s’est enrichie architecturalement á travers le temps avec les apports stylistiques des différentes dynasties. Cette ville a été classée secteur sauvegardé en 2009 par décret exécutif. Le tracé géographique de ce secteur ne touche que la médina islamique de Tagrart excluant le reste de la ville. De ce fait, nous nous sommes interrogés sur les véritables limites de cette cité millénaire. Pour cela, nous avons retracé son patrimoine urbain en étudiant la stratification et les caractéristiques des tissus urbains. Ce nouveau tracé géographique démontre l’exclusion de nombreuses zones historiques du classement patrimonial.

Description du sujet. Dans les pays sahéliens, la répartition spatio-temporelle hautement variable des précipitations demeure une menace pour l'agriculture pluviale, malgré le grand nombre de techniques diffusées pour la conservation des eaux et des sols. Objectifs. Analyser plusieurs stratégies d'irrigation des cultures pluviales et évaluer l'impact probable des mesures économiques incitatives en vue de faciliter l'adoption de l'irrigation de complément à partir des petits bassins individuels de collecte des eaux de ruissellement face aux poches de sècheresse. Méthode. Les stratégies possibles d'irrigation de complément et les simulations des mesures économiques incitatives ont été analysées à partir d'un modèle bio-économique appliqué à une exploitation agricole type. Résultats. Les simulations montrent que l'irrigation de complément permet d'accroitre le revenu espéré des agriculteurs, comparativement à la situation sans irrigation. La culture du maïs, du sorgho et du mil sous l'irrigation de complément en année sèche augmente le revenu espéré de 26,49 % (133 030 francs CFA, équivalent à 202,80 euros) comparativement à la situation sans irrigation. Les simulations visant à promouvoir l'irrigation de complément à partir des petits bassins individuels sont axées sur quatre modalités de subventions et un système d'octroi de crédit aux ménages agricoles. Conclusions. Parmi les mesures incitatives, la subvention sous forme de travail contre nourriture pour mobiliser la main-d'oeuvre en vue de construire les bassins semble particulièrement adaptée pour la mise à l'échelle de la pratique de l'irrigation de complément à partir des petits bassins individuels.

At the beginning of the drought in the Sahel in the 1970s and 1980s, rainfall decreased markedly, but runoff coefficients and in some cases, absolute runoff increased. This situation was due to the conversion of the land cover from natural vegetation with a low annual runoff coefficient, to cropland and bare soils, whose runoff coefficients are higher. Unless they are adapted, hydrological conceptual models, such as GR2M, are unable to reproduce this increase in runoff. Despite the varying environmental and climatic conditions of the West African Sahel, we show that it is possible to increase the performance of the GR2M model simulations by elaborating a time-varying soil water holding capacity and to incorporate this value in the annual maximum amount of water to be stored in reservoir A of the model. We looked for interactions between climate, rural society, and the environment. These interactions drive land-cover changes in the Sahel, which in turn drive the distribution of rainfall between infiltration, evaporation, and runoff and hence the water resources, which are vital in this region. We elaborated several time series of key indicators linked to these interactions. We then integrated these changes in the runoff conditions of the GR2M model through the maximum value of the reservoir capacity. We calculated annual values of water holding capacity using the annual values of four classes of land cover, natural vegetation, cultivated area, bare soil, and surface water. We then used the hydrological model with and without this time-varying soil value of A and compared the performances of the model under the two scenarios. Whatever the calibration period used, the Nash–Sutcliffe index was always greater in the case of the time-varying A time series.

Rain-fed farming is the primary livelihood of semi-arid west Africa. Changes in land cover have the potential to affect precipitation, the critical resource for production. Turbulent flux measurements from two eddy-covariance towers and additional observations from a dense network of small, wireless meteorological stations combine to relate land cover (savanna forest and agriculture) to evaporation in a small (3.5km2) catchment in Burkina Faso, west Africa. We observe larger sensible and latent heat fluxes over the savanna forest in the headwater area relative to the agricultural section of the watershed all year. Higher fluxes above the savanna forest are attributed to the greater number of exposed rocks and trees and the higher productivity of the forest compared to rain-fed, hand-farmed agricultural fields. Vegetation cover and soil moisture are found to be primary controls of the evaporative fraction. Satellite-derived vegetation index (NDVI) and soil moisture are determined to be good predictors of evaporative fraction, as indicators of the physical basis of evaporation. Our measurements provide an estimator that can be used to derive evaporative fraction when only NDVI is available. Such large-scale estimates of evaporative fraction from remotely sensed data are valuable where ground-based measurements are lacking, which is the case across the African continent and many other semi-arid areas. Evaporative fraction estimates can be combined, for example, with sensible heat from measurements of temperature variance, to provide an estimate of evaporation when only minimal meteorological measurements are available in remote regions of the world. These findings reinforce local cultural beliefs of the importance of forest fragments for climate regulation and may provide support to local decision makers and rural farmers in the maintenance of the forest areas., Water Resources

At the beginning of the drought in the Sahel in the 1970s and 1980s, rainfall decreased markedly, but runoff coefficients and in some cases, absolute runoff increased. This situation was due to the conversion of the land cover from natural vegetation with a low annual runoff coefficient, to cropland and bare soils, whose runoff coefficients are higher. Unless they are adapted, hydrological conceptual models, such as GR2M, are unable to reproduce this increase in runoff. Despite the varying environmental and climatic conditions of the West African Sahel, we show that it is possible to increase the performance of the GR2M model simulations by elaborating a time-varying soil water holding capacity and to incorporate this value in the annual maximum amount of water to be stored in reservoir A of the model. We looked for interactions between climate, rural society, and the environment. These interactions drive land-cover changes in the Sahel, which in turn drive the distribution of rainfall between infiltration, evaporation, and runoff and hence the water resources, which are vital in this region. We elaborated several time series of key indicators linked to these interactions. We then integrated these changes in the runoff conditions of the GR2M model through the maximum value of the reservoir capacity. We calculated annual values of water holding capacity using the annual values of four classes of land cover, natural vegetation, cultivated area, bare soil, and surface water. We then used the hydrological model with and without this time-varying soil value of A and compared the performances of the model under the two scenarios. Whatever the calibration period used, the Nash–Sutcliffe index was always greater in the case of the time-varying A time series.

Rain-fed farming is the primary livelihood of semi-arid west Africa. Changes in land cover have the potential to affect precipitation, the critical resource for production. Turbulent flux measurements from two eddy-covariance towers and additional observations from a dense network of small, wireless meteorological stations combine to relate land cover (savanna forest and agriculture) to evaporation in a small (3.5km2) catchment in Burkina Faso, west Africa. We observe larger sensible and latent heat fluxes over the savanna forest in the headwater area relative to the agricultural section of the watershed all year. Higher fluxes above the savanna forest are attributed to the greater number of exposed rocks and trees and the higher productivity of the forest compared to rain-fed, hand-farmed agricultural fields. Vegetation cover and soil moisture are found to be primary controls of the evaporative fraction. Satellite-derived vegetation index (NDVI) and soil moisture are determined to be good predictors of evaporative fraction, as indicators of the physical basis of evaporation. Our measurements provide an estimator that can be used to derive evaporative fraction when only NDVI is available. Such large-scale estimates of evaporative fraction from remotely sensed data are valuable where ground-based measurements are lacking, which is the case across the African continent and many other semi-arid areas. Evaporative fraction estimates can be combined, for example, with sensible heat from measurements of temperature variance, to provide an estimate of evaporation when only minimal meteorological measurements are available in remote regions of the world. These findings reinforce local cultural beliefs of the importance of forest fragments for climate regulation and may provide support to local decision makers and rural farmers in the maintenance of the forest areas., Water Resources

Haibat Sultan Mountain is a long range with elevation of about 860 m (a.s.l.); the PilaSpi Formation forms its carapace in Koya vicinity, with relief difference of about 300 m from Koisanjaq plain. The PilaSpi Formation consists of well thickly to massively bedded dolostone and dolomitic limestone with thickness of about 120 m in Koya vicinity. The main trend is NW - SE being a limb of Bustana anticline representing part of the southwestern limb, with dip amount that ranges from (15 - 30). On 11th of November 2015 a landslide had occurred after a heavy rainfall along Koya - Dukan main road. The type of the slide was plane sliding due to daylight slope, which was formed afterthe road cut. The length of the slide area: along the road is 90 m with height of 40 m forming almost a parallelogram shape; the thickness of the slid beds is about 2.5 m. The estimated volume of the slid mass is 9000 m3. The main cause of the landslide is the presence of daylight slope, high slope angle; more than the dip angle, presence of old crack surfaces which are filled by reddish brown clayey residual soil. After the he heavy rain fall, which lasted for 20 hours, the infiltrated rain water in the bedding planes in the well bedded, cracked, and jointed beds has increased the pore pressure and decreased the internal friction angle; therefore, the sliding has occurred. The root of the slid mass is below the base of the paved road; therefore, that part which is above the paved road has slid. The remaining part is highly cracked and partly accumulated in the base of the slid mass. Fortunately, the height of the slid mass is only 40 m and the relief difference between the crown area and the toe area is about 50 m; otherwise the slid mass would be larger than the present slid mass. From the field inspection, it is very clear that the involved area is very unstable and in critical equilibrium. The presence of daylight bedding above the crown area, clayey soil in the fractures and open joints and, Validerad; 2016; Nivå 1; 20160825 (nadhir)

Haibat Sultan Mountain is a long range with elevation of about 860 m (a.s.l.); the PilaSpi Formation forms its carapace in Koya vicinity, with relief difference of about 300 m from Koisanjaq plain. The PilaSpi Formation consists of well thickly to massively bedded dolostone and dolomitic limestone with thickness of about 120 m in Koya vicinity. The main trend is NW - SE being a limb of Bustana anticline representing part of the southwestern limb, with dip amount that ranges from (15 - 30). On 11th of November 2015 a landslide had occurred after a heavy rainfall along Koya - Dukan main road. The type of the slide was plane sliding due to daylight slope, which was formed afterthe road cut. The length of the slide area: along the road is 90 m with height of 40 m forming almost a parallelogram shape; the thickness of the slid beds is about 2.5 m. The estimated volume of the slid mass is 9000 m3. The main cause of the landslide is the presence of daylight slope, high slope angle; more than the dip angle, presence of old crack surfaces which are filled by reddish brown clayey residual soil. After the he heavy rain fall, which lasted for 20 hours, the infiltrated rain water in the bedding planes in the well bedded, cracked, and jointed beds has increased the pore pressure and decreased the internal friction angle; therefore, the sliding has occurred. The root of the slid mass is below the base of the paved road; therefore, that part which is above the paved road has slid. The remaining part is highly cracked and partly accumulated in the base of the slid mass. Fortunately, the height of the slid mass is only 40 m and the relief difference between the crown area and the toe area is about 50 m; otherwise the slid mass would be larger than the present slid mass. From the field inspection, it is very clear that the involved area is very unstable and in critical equilibrium. The presence of daylight bedding above the crown area, clayey soil in the fractures and open joints and, Validerad; 2016; Nivå 1; 20160825 (nadhir)

This study highlights the perception and the option value of climate information in the sahelian and sudano-sahelian agro-climatic zones of Burkina Faso. From the sampled farmers only 21.78% have access to climate information, while 93% of them need climate information to guide through their decision in planning agricultural activities. Option value shows the interest granted by farmers using climate information. About 64% of the farmers are willing to pay an average of Francs CFA 546.34 to obtain climate information. The willingness to pay is determined by the the farmers' ability to predict the climate, to use radio as a means of information, farmers' awareness of previous forecasts and early onset of rainy season. While farmers considered benefits from the use of climate information, it is clear that its contribution to farm income remains a field of research to explore. Thus it is necessary to experiment with individual farms and to evaluate the contribution of climate information to the value added in different crops and farmers' income.

We explore the constraints following from requiring the Area Law in the entanglement entropy in the context of loop quantum gravity. We find a unique solution to the single link wave-function in the large j limit, believed to be appropriate in the semi-classical limit. We then generalize our considerations to multi-link coherent states, and find that the area law is preserved very generically using our single link wave-function as a building block. Finally, we develop the framework that generates families of multi-link states that preserve the area law while avoiding macroscopic entanglement, the space-time analogue of "Schroedinger cat". We note that these states, defined on a given set of graphs, are the ground states of some local Hamiltonian that can be constructed explicitly. This can potentially shed light on the construction of the appropriate Hamiltonian constraints in the LQG framework., Comment: 6+5 pages, 2 figures, presentation improved, appendices added, revised version accepted for publication in Physical Review D

We explore the constraints following from requiring the Area Law in the entanglement entropy in the context of loop quantum gravity. We find a unique solution to the single link wave-function in the large j limit, believed to be appropriate in the semi-classical limit. We then generalize our considerations to multi-link coherent states, and find that the area law is preserved very generically using our single link wave-function as a building block. Finally, we develop the framework that generates families of multi-link states that preserve the area law while avoiding macroscopic entanglement, the space-time analogue of "Schroedinger cat". We note that these states, defined on a given set of graphs, are the ground states of some local Hamiltonian that can be constructed explicitly. This can potentially shed light on the construction of the appropriate Hamiltonian constraints in the LQG framework., Comment: 6+5 pages, 2 figures, presentation improved, appendices added, revised version accepted for publication in Physical Review D

This study was carried out in the Burkinabe Sahel aimed at studying contribution of the practice of supplemental irrigation (SI) via excavated rainwater harvesting basin (RWHB) for mitigating effect of rainfall variability on agricultural production and impact of these RWHB on the dynamics of the water table. This study was conducted during two growing seasons (2013 and 2014) and used a test plot cultivated in corn and fitted out with measuring instruments to analyze water transfer in the soil-plant-atmosphere system on the one hand and the atmosphere-RWHB-water table system on the other hand. Four treatments—one under rainfall regime (T0) and three under SI (T1, T2, and T3)—were used in the experimental design to assess the contribution of the RWHB in improving corn yield. These SI were applied during the mid-season of corn (flowering, pollination, and grain filling). Water flow beneath a partially waterproofed RWHB was assessed using HYDRUS- 2D/3D program. Results showed that water stored in the RWHB allowed applying up to three SI, and increased corn yield up to 24% and 26% respectively in 2013 and 2014. However, SI targeting flowering and grain filling were the best scenarios to mitigate effect of dry spell in rainfed agriculture. Water flow under RWHB during the simulation period showed that dynamic of the saturated front depended on the magnitude of the water depth in the RWHB and the hydrodynamic characteristics of the underlying layers. Deep drainage was observed around 25th day after sowing (DAS) in 2013 and 45th DAS in 2014 according to water profile. This caused the decrease of the infiltration rate in the RWHB that was associated with a significant rise of 4% of the water table level ten days later in 2014. Recharge rate was estimated at 0.5 mm∙d−1 during the mid-season and the late season of corn.

This research conducted in the Tougou watershed located in North of Burkina Faso aims at assessing the impact of soil degradation on the water transfer in the soil-plant-atmosphere continuum. Field measurements were performed through an experimental design made of plots measuring 1 m2 each and established on three sites of the watershed: three plots on an erosion crust (PZN), three plots on a desiccation crust supported herbaceous (PZD) and three plots on an area cultivated in sorghum (PZC). Each site was equipped with tensiometric and neutron tubes to measure pressure head and water content of the soil. Results showed that PZN was characterized by a low infiltration capacity enhancing runoff. The water stored during the rain periods is low and remains localized within the first 30 or even 40 cm top of soil, which promoted a quick evaporative recovery in days following the rainy event. PZD and PZC were characterized by a good hydraulic conductivity and a high infiltration speed. The infiltrated water was important and the drainage beyond the depth of 70 cm was observed during important rain events. The real daily average evapotranspiration varied between 3 and 4 mm on the all sites.

This study analyzes farmers' practices and willingness to adopt supplemental irrigation on rain fed crops in the Sahelian and Sudano - Sahelian areas of Burkina Faso. A survey of 629 farmers revealed a diversity of farming practices within and between two agro - climatic zones. Over 65% of farmers believe that supplemental irrigation is a good way to mitigate the adverse effects of dry spells on cr op yields. Determining factors of farmers' willingness to adopt supplemental irrigation were identified using a logistic model. Lack of information is the major obstacle to promoting this innovation. Farmers' training and information dissemination are the best ways to increase the acceptance of this promising technology.

This study aims to isolate the supplemental irrigation (SI) scenario from permeable rainwater harvesting basins (RWHBs) best suitable to mitigate the long dry spells (DSs) in Burkinabe Sahel (BS). The water flow in the soil was studied on corn crop during 2013 and 2014 depending on the available water in the monitored RWHB. The experimental design was a block Fisher with four treatments (one under rainfed regime and three under supplemental irrigation). Measurements of the soil water content revealed periods of corn water sufficiency in plots under SI. Average corn yields were respectively 4500 and 4600 kg ha-1 for 2013 and 2014 on plots under SI against 3700 and 3800 kg ha-1 for those in rainfed regime. The average contribution of the SI in increasing corn yield was respectively 24 and 26% in 2013 and 2014 for three supplemental irrigations (SIs), against 19 and 17% for two SIs. With these SIs, the water balance in the RWHB gave respectively at the end of 2013 and 2014, an available water of 60 and 81 mm. The suitable strategy of the SI to mitigate DSs effect in BS was applying two SIs with a dose at least 40 mm around the mid-season.

In Burkina Faso, agriculture is the main activity of rural households. It occupies more than two thirds of the workforce and contributes more than a third to gross domestic product. Mainly rainfed, it is a subsistence agriculture which is still little mechanized and therefore highly dependent on climate conditions. In recent decades, climate change has greatly weakened the traditional systems of production through flooding, uncertainty about the dates of the beginning and end of the rainy season and with longer and more recurrent dry spells. Supplemental irrigation consists in bringing water to crops in case of dry spells, by mobilizing water from a dam, a boulis, a well or any other water resource. For areas far away from these water resources, runoff harvesting basins which are built to collect water and irrigate crops in case of dry spells, contribute to the sustainable management of waters and lands. The practice is increasingly accepted in the farmer environment and the government plans to subsidize the construction of over 10,000 basins in 10 of the 13 administrative regions of the country. A literature review combined with producer surveys and experiments, conducted within the framework of a research-development project on supplemental irrigation and climate information, allowed to obtain a number of results. Supplemental irrigation as the only discriminating parameter between two agricultural plots enables improved yields of over 25%. The early start of the campaign may be wedged since the first rains from the second decade of May, by keeping animals in sheds and under the condition of a period not longer than twenty days, between the first rains able to fill the basin and the actual start of the rainy season. According to the agro-climatic zone and the level of sealing of the basin, water can be stored between 30 and 90 days after the last rains, allowing extending the campaign by gardening or relay cropping. By combining supplemental irrigation with techni

In this paper, using a Bessel generalized translation, we prove the estimates for the Bessel transform in the space $\mathrm{L}_p^2\left(\mathbb{R}_{+}\right)$on certain classes of functions.

In this paper, using a Bessel generalized translation, we prove the estimates for the Bessel transform in the space \(\mathrm{L}_p^2\left(\mathbb{R}_{+}\right)\) on certain classes of functions.

In this paper, using a Bessel generalized translation, we prove the estimates for the Bessel transform in the space \(\mathrm{L}_p^2\left(\mathbb{R}_{+}\right)\) on certain classes of functions.

This study analyzes farmers' practices and willingness to adopt supplemental irrigation on rain fed crops in the Sahelian and Sudano - Sahelian areas of Burkina Faso. A survey of 629 farmers revealed a diversity of farming practices within and between two agro - climatic zones. Over 65% of farmers believe that supplemental irrigation is a good way to mitigate the adverse effects of dry spells on cr op yields. Determining factors of farmers' willingness to adopt supplemental irrigation were identified using a logistic model. Lack of information is the major obstacle to promoting this innovation. Farmers' training and information dissemination are the best ways to increase the acceptance of this promising technology.

This study was carried out in the Burkinabe Sahel aimed at studying contribution of the practice of supplemental irrigation (SI) via excavated rainwater harvesting basin (RWHB) for mitigating effect of rainfall variability on agricultural production and impact of these RWHB on the dynamics of the water table. This study was conducted during two growing seasons (2013 and 2014) and used a test plot cultivated in corn and fitted out with measuring instruments to analyze water transfer in the soil-plant-atmosphere system on the one hand and the atmosphere-RWHB-water table system on the other hand. Four treatments—one under rainfall regime (T0) and three under SI (T1, T2, and T3)—were used in the experimental design to assess the contribution of the RWHB in improving corn yield. These SI were applied during the mid-season of corn (flowering, pollination, and grain filling). Water flow beneath a partially waterproofed RWHB was assessed using HYDRUS- 2D/3D program. Results showed that water stored in the RWHB allowed applying up to three SI, and increased corn yield up to 24% and 26% respectively in 2013 and 2014. However, SI targeting flowering and grain filling were the best scenarios to mitigate effect of dry spell in rainfed agriculture. Water flow under RWHB during the simulation period showed that dynamic of the saturated front depended on the magnitude of the water depth in the RWHB and the hydrodynamic characteristics of the underlying layers. Deep drainage was observed around 25th day after sowing (DAS) in 2013 and 45th DAS in 2014 according to water profile. This caused the decrease of the infiltration rate in the RWHB that was associated with a significant rise of 4% of the water table level ten days later in 2014. Recharge rate was estimated at 0.5 mm∙d−1 during the mid-season and the late season of corn.

This research conducted in the Tougou watershed located in North of Burkina Faso aims at assessing the impact of soil degradation on the water transfer in the soil-plant-atmosphere continuum. Field measurements were performed through an experimental design made of plots measuring 1 m2 each and established on three sites of the watershed: three plots on an erosion crust (PZN), three plots on a desiccation crust supported herbaceous (PZD) and three plots on an area cultivated in sorghum (PZC). Each site was equipped with tensiometric and neutron tubes to measure pressure head and water content of the soil. Results showed that PZN was characterized by a low infiltration capacity enhancing runoff. The water stored during the rain periods is low and remains localized within the first 30 or even 40 cm top of soil, which promoted a quick evaporative recovery in days following the rainy event. PZD and PZC were characterized by a good hydraulic conductivity and a high infiltration speed. The infiltrated water was important and the drainage beyond the depth of 70 cm was observed during important rain events. The real daily average evapotranspiration varied between 3 and 4 mm on the all sites.