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The exponential growth of the photovoltaic system installations also requires an adequate maintenance and supervision system to ensure the continuity of service of the system. Conventional protection systems for electrical systems have shown their shortcomings for protecting photovoltaic systems. In this article, a statistical approach based on principal component analysis and its variants is used to detect and identify faults in a photovoltaic array. This involves analysing the variations of the data of the current–voltage and voltage–power characteristics. Subsequently, the calculation of the contributions is applied to the SPE index for the identification of faults. By employing the intermediate value theorem, six different operating states have been identified. The various results obtained first from the simulation model from the Simulink environment and then from a real system of 18 PV show that the kernel principal component analysis allows defect detection with a better precision.

Improving the efficiency of photovoltaic (PV) systems has gained priority in current research due to the large volumes of PV panels installed. Moreover, the remarkable efforts made to investigate d...

The word’s demand for renewable energy has be rinsing incrementally. One of the solutions for the energy crisis is photovoltaic. However, the design and development of better performing photovoltaic cells and modules requires accurate extraction of their intrinsic parameters. Metaheuristic algorithms have been reported to be the best methods for obtaining accurate values of these intrinsic parameters. However, local convergence goes against the recently devised heuristic methods and inhibits them from producing optimal result. This paper proposes a hybrid method that is based on the Newton Raphson method and a self-adaptive algorithm called the Drone Squadron Optimisation. The latter is an artifact technique inspired by the simulation of a drone squadron from a command centre. It is proposed that this hybrid method can help extract the best intrinsic parameters of photovoltaic cell and module. This study also provides insights and clarification on the reported approaches that have been recently proposed to formulate the objective function. Further, this study also computes and compares the ten best recently published heuristics algorithms in the domain of photovoltaic estimation. The study’s results obtain point to the difference between the two formulations and the accuracy of the best formulation. The results obtained from the six case studies covered in this study present the combined performance of the Newton Raphson method and Drone Squadron Optimisation to extract the accurate parameters of a photovoltaic module.

The model of nonlinear power generation function is developed to generate optimal operational policies for Songloulou inflow in Cameroon and test these policies in real time conditions. Our model is used to adjust operational regimes for the Songloulou reservoir under varying flows (turbined and deversed) using a dynamic program. A more interesting approach, proposed in this article, consists of combining both the principle of decomposition by resources (or quantities) and the technique of dynamic programming. Dynamic programming is an appropriating optimization algorithm that is used for complex non-linear inflow operational policies and strategies. In this case study, our optimization model is used and confirmed maximizing large scale of hydropower in a period of time step by the integration of several. The high non linearity of our study object is the first stage of difficulty which brought us to combined least squared and Time Varying Acceleration Coefficients Particle Swarm (TVACPSO) to obtain appropriate production function which generated optimal operational policies for the Songloulou hydropower in sub-Saharan region and after we tested it in the company policies operational at real time conditions. The model could be successfully applied to other hydropower dams in the region.

Souvent frappée par des crises sanitaires, l’Afrique est constamment confrontée aux difficultés d’accès aux médicaments résultant de la protection des droits de propriété intellectuelle (DPI). L’avènement de la pandémie de Covid-19 rappelle des débats devenus vifs ces trois dernières décennies, relativement au sort à réserver aux DPI couvrant les médicaments nécessaires à la prise en charge des populations. À cet effet, les organisations régionales africaines de propriété intellectuelle, dans le cadre de l’Union africaine, mais surtout de l’Organisation régionale africaine de la propriété intellectuelle (ARIPO) et de l’Organisation africaine de la propriété intellectuelle (OAPI) disposent de règles pertinentes destinées à régir l’utilisation des DPI. Entre incitation à la recherche innovante tout en ménageant des flexibilités qui atténuent la rigueur des DPI, et crainte de restreindre l’accès aux résultats de la recherche, le droit généré par ces organisations régionales fournit-il des réponses appropriées pour l’accès aux médicaments? Tantôt encouragé par les DPI existants, tantôt perturbé en raison d’enjeux spécifiques comme la question de la protection des médicaments traditionnels, l’accès aux médicaments est une préoccupation centrale pour les Organisations régionales africaines désireuses de jouer leur partition dans la recherche de l’équilibre entre droits privatifs des titulaires de DPI et intérêt général associé à l’accès aux médicaments.

To evaluate the performance of a photovoltaic panel, several parameters must be extracted from the photovoltaic. These parameters are very important for the evaluation, monitoring and optimization of photovoltaic. Among the methods developed to extract photovoltaic parameters from current-voltage (I-V) characteristic curve, metaheuristic algorithms are the most used nowadays. A new metaheuristic algorithm namely enhanced vibrating particles system algorithm is presented here to extract the best values of parameters of a photovoltaic cell. Five recent algorithms (grey wolf optimization (GWO), moth-flame optimization algorithm (MFOA), multi-verse optimizer (MVO), whale optimization algorithm (WAO), salp swarm-inspired algorithm (SSA)) are also implemented on the same computer. Enhanced vibrating particles system is inspired by the free vibration of the single degree of freedom systems with viscous damping. To extract the photovoltaic parameters using enhanced vibrating particles system algorithm, the problem can be set as an optimization problem with the objective to minimize the difference between measured and estimated current. Four case studies have been implemented here. The results and comparison with other methods exhibit high accuracy and validity of the proposed enhanced vibrating particles system algorithm to extract parameters of a photovoltaic cell and module.

Parameters extraction is instrumental to standard PV cells design. Reports indicates that heuristic algorithms are the most effective methods for accurately determinining the values of parameters. However, local concentration is against recent heuristic methods, and they are inhibited producing optimal results. This paper seeks to show that combining the heuristics algorithms with the Newton Raphson method can considerably increased the accuracy of results. An inspired artifact technique from the drone squadron simulation from control center is proposed for the extraction of the best constitutive parameters. This study equally provides clarifications on the approaches recently reported and proposed to build objective function. Furthermore, comparative evaluation of the current ten best heuristics algorithms that are published in the PV estimation domain is also undertaken. Moreover, this study investigates the convergence of algorithms when points of the number of current-voltage characteristics are varied. The results from this study highlight the differences between the two formulation, and it shows the best formulation accuracy. The results obtained from seven study cases that are considered in this present study, with the combined Newton Raphson performance method and Drone Squadron optimisation, were employed to extract precise PV module parameters.The study of the numbers of points reveals that the algorithm converges and is more precise when the numbers of points of the I-V characteristic are reduced. However, if these points are minimal, the algorithm will be hindered from returning optimal results., Solar energy modelisation, Parameters identifications, Photocells, Photovoltaic modules, Optimization of drone units, Heuritics algorithms.

La pandémie à Coronavirus 2019 (COVID-19) touche les pays d´Afrique sub-Saharienne depuis le mois de mars 2020. Au-delà des désastres sanitaire et économique causés, se pose un problème psycho-socio-culturel en rapport avec la gestion des corps de personnes décédées de cette maladie; ce problème est susceptible d´entraver la bonne marche de la stratégie de riposte. Au Cameroun par exemple, la gestion actuelle de ces dépouilles ne fait pas l´unanimité. En effet, les restrictions appliquées à l´inhumation, bien que récemment assouplies proscrivent entre autres tout transfert interurbain des dépouilles. A la lumière des considérations culturelles africaines de la personne décédée, des dissensions créées entre les familles et le corps médical, de la législation et des données scientifiques disponibles, cet article analyse les risques et les bénéfices de l´inhumation des dépouilles par les familles. Il propose ensuite des solutions qui concilient la dignité (en laissant les familles enterrer leurs morts dans les domiciles), et la sécurité (en assurant une conservation hermétique et la surveillance d´un officier de police judiciaire). L´application de ces solutions pourraient améliorer la confiance de la population envers le système de santé et contribuer positivement aux stratégies de prévention, d´identification et de prise en charge des cas de COVID-19.

La pandemie a Coronavirus 2019 (COVID-19) touche les pays d´Afrique sub-Saharienne depuis le mois de mars 2020 Au-dela des desastres sanitaire et economique causes, se pose un probleme psycho-socio-culturel en rapport avec la gestion des corps de personnes decedees de cette maladie;ce probleme est susceptible d´entraver la bonne marche de la strategie de riposte Au Cameroun par exemple, la gestion actuelle de ces depouilles ne fait pas l´unanimite En effet, les restrictions appliquees a l´inhumation, bien que recemment assouplies proscrivent entre autres tout transfert interurbain des depouilles A la lumiere des considerations culturelles africaines de la personne decedee, des dissensions creees entre les familles et le corps medical, de la legislation et des donnees scientifiques disponibles, cet article analyse les risques et les benefices de l´inhumation des depouilles par les familles Il propose ensuite des solutions qui concilient la dignite (en laissant les familles enterrer leurs morts dans les domiciles), et la securite (en assurant une conservation hermetique et la surveillance d´un officier de police judiciaire) L´application de ces solutions pourraient ameliorer la confiance de la population envers le systeme de sante et contribuer positivement aux strategies de prevention, d´identification et de prise en charge des cas de COVID-19

Obesity epidemic continues to spread and obesity rates are increasing in the world. In addition to public health effort to reduce obesity, there is a need to better understand the underlying biology to enable more effective treatment and the discovery of new pharmacological agents. Abhydrolase domain-containing protein 11 (ABHD11) is a serine hydrolase enzyme, localized in mitochondria, that can synthesize the endocannabinoid 2-arachidonoyl glycerol (2AG) in vitro. In vivo preclinical studies demonstrated that knock-out ABHD11 mice have a similar 2AG level as WT mice and exhibit a lean metabolic phenotype. Such mice resist to weight gain in Diet Induced Obesity studies (DIO) and display normal biochemical plasma parameters. Metabolic and transcriptomic analyses on serum and tissues of ABHD11 KO mice from DIO studies show a modulation in bile salts associated with reduced fat intestinal absorption. These data suggest that modulating ABHD11 signaling pathway could be of therapeutic value for the treatment of metabolic disorders.

To evaluate the performance of a photovoltaic panel, several parameters must be extracted from the photovoltaic. Among the methods developed to extract photovoltaic parameters from current-voltage (I-V) characteristic curve, metaheuristic algorithms are the most used nowadays. The aim of this paper is to present the inaccuracies occurred in the parameter’s identification of the photovoltaic cell using metaheuristic technics published in Energy Conversion and Management. The results presented by different authors do not meet the objective function. To prove it, an algorithm is proposed to check the accuracy of the proposed results; a simple tool, General Algebraic Modeling System is also proposed to extract the best values of parameters of a photovoltaic cell.

Les innovations en matière variétale et de biotechnologie végétale sont présentées comme un moyen efficace et approprié susceptible de favoriser l'amélioration de la production alimentaire et des conditions de travail et de vie des agriculteurs ainsi que celles des collectivités coutumières dans les pays membres de l'Organisation africaine de la propriété intellectuelle (OAPI). Sur le plan juridique, il se pose le problème de la protection juridique de ces innovations ou obtentions végétales. Le législateur OAPI de 1977 n'avait pas envisagé de protection pour les obtentions végétales. À la différence de certains États industrialisés qui organisaient un régime de protection sui generis ou par le système des brevets, il n'évoquait les variétés végétales et les procédés d'obtention des végétaux que pour les exclure du domaine brevetable. L'accord sur les aspects des droits de propriété intellectuelle qui touchent au commerce (ADPIC) de l'organisation mondiale du commerce (OMC) est venu modifier la donne en imposant que les obtentions végétales puissent être protégées par les brevets, par un système sui generis ou par une combinaison des deux moyens. Le législateur OAPI de 1999 a voulu intégrer ces nouvelles exigences internationales en révisant l'Accord de Bangui. Ce faisant, l'exclusion de la brevetabilité des variétés végétales a été maintenue. Il ne restait plus au législateur qu'une seule option, l'adoption d'un régime de protection sui generis. Son choix s'est matérialisé par l'adoption de l'annexe X de l'Accord de Bangui de 1999 consacrée à « la protection des obtentions végétales ». Cette annexe est calquée sur la version de 1991 de la Convention Internationale pour la protection des obtentions végétales, mise en place par les pays européens. Il s'agit là d'un choix discutable. En effet, l'annexe X introduit dans l'espace OAPI une législation désincarnée, parce que à la fois incomplète et inadaptée à l'environnement socio-économique des pays membres de l'OAPI., Innovations related to biotechnology and plant varieties are regarded as an efficient and suitable means to enhance the improvement of food production, lives and working conditions of farmers as well as those of local communities in the member States of the African Intellectual Property Organization (OAPI). From a legal point of view, the legal protection of those innovations on plant varieties is questionable. The legislator of the OAPI Law of 1977 had not considered any protection for plant varieties. Contrary to some industrialized countries where a sui generis system of protection or a protection by the patent system were organized, plant varieties and biological processes for the breeding of plants were mentioned only to be excluded from the patentable domain. The Trade Related Aspects of Intellectual Property Rights (TRIPs) Agreement of the World Trade Organisation (WTO) modified the situation by imposing that plant varieties shall be protected either by patents or by a sui generis system or through the combination of the two methods. The legislator of the OAPI Law of 1999 wanted to incorporate these new international requirements while amending the Bangui Agreement. At the same time,the plant varieties' exclusion from patentability was maintained. Hence, the legislator had no other option than adopting a sui generis regime of protection. He materialized this option by inserting in the Bangui Agreement of 1999, the Annex X related to the “Plant Variety Protection”. This appendix is drafted in light of the 1991's version of the International Convention for the Protection of New Varieties of Plants put in place by the European countries. This choice remains questionable. Indeed, the Annex X introduces in the OAPI zone a disembodied legislation, because it is incomplete and unsuited to the socioeconomic environment of the member States of the OAPI.