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Journal of Water Resource and Protection 2024年第1期16卷 83-101页

作者： Kouadio Michel yao Tanina Drissa Soro Tanoh Jean Jacques Koua Akaie Jean Fabrice Tchakray yao Emile Desmond konan Brou Dibi Laboratory of Sciences and Technologies of Environment University Jean Lorougnon Guede Daloa C&ocircte d’Ivoire

The main objective of this study is to determine the hydrogeochemical specificities of the groundwater of the Angovia mine operating permit, located in the yaouré mountains in the center-west of Côte d’Ivoire. To do so, descriptive and multivariate statistical analysis methods with the SOM (Self Organizing Maps) algorithm were applied to the physicochemical parameters of 17 boreholes using the calcite (ISC) and dolomite (ISD) saturation indices. The results obtained have shown that the groundwater in the Angovia mine operating permit area has an average temperature of 27.52°C (long rainy season) and 27.87°C (long dry season) and has an average pH of 7.09 ± 0.35 during the main rainy season and 7.32 ± 0.35 during the main dry season. They are mineralized with an average electrical conductivity of 505.98 ± 302.85 μS/cm during the long rainy season and with 450.33 ± 233.74 μS/cm as average during the long dry season. The main phenomena at the origin of groundwater mineralization are water residence time, oxidation-reduction and surface inflow. The study of the relative age of the water shows that the groundwater in the Angovia mine operating permit area is mainly undersaturated with respect to calcite and dolomite. They are therefore very old in the aquifer with a slow circulation speed during the long rainy season and the long dry season.

关键词： Hydrogeochemistry Mineralization Fissure Aquifers Operating Permits The Angovia Mine

Analysis of Students’ Preferences and Engagement with Mobile Games: A Study of Game Assets and Colour Impact

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Open Journal of Applied Sciences 2023年第12期13卷 2211-2222页

作者： Venance Saho Zoh Tiémoman Koné yao konan Informatique et Sciences du Numérique Université Virtuelle de C&#244te d’Ivoire Abidjan C&#244te d’Ivoire

Mobile games are gaining in popularity among students, although the factors driving engagement remain poorly understood. This study, conducted among 378 students studying for a Bachelor’s degree in Computer and Digital Sciences at the Université Virtuelle de Côte d’Ivoire, explores the influence of game assets and colours on player engagement. Using an online questionnaire, the study identified students’ gaming preferences and their perception of colours. The results show that the key elements most favoured by students are graphics, sound design, the game system, narrative, interactivity and accessibility. What’s more, colour plays a decisive role in their preferences and commitment to educational mobile games.

关键词： Engagement Game Assets Colour Mobile Games

Formation of an Original Database and Development of Innovative Deep Learning Algorithms for Detecting Face Impersonation in Online Exams

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Open Journal of Applied Sciences 2023年第12期13卷 2223-2232页

作者： konan yao Tiémoman Kone Venance Saho Zoh Department of Computer Science and Digital Science Virtual University of C&#244te d’Ivoire Abidjan C&#244te d’Ivoire

The issue related to the risk of identity impersonation, where one person can be replaced by another in online exam surveillance systems, poses challenges. This study focuses on the effectiveness of detecting attempts of identity impersonation through face substitution during online exams, with the aim of ensuring the integrity of assessments. The goal is to develop facial recognition algorithms capable of precisely detecting these impersonations, training them on a tailored database rather than biased generic data. An original database of student faces has been created. An algorithm leveraging advanced deep learning techniques such as depthwise separable convolution has been developed and evaluated on this database. We achieved very high levels of precision, reaching an accuracy rate of 98% in face detection and recognition.

关键词： Online Exams Face Recognition Convolutional Neural Networks Data Bias

Clinical Factors Influencing the Neurological Recovery of Patients Operated for a Cervical Myelopathy at the Teaching Hospital of Bouake

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Open Journal of Modern Neurosurgery 2023年第2期13卷 51-59页

作者： Derou Louis Dongo Soress yao konan Serge Teti Landry Keke Jean-Baptiste Fionko yao Bernard Tokpa André Broalet Espérance Haidara Aderehime Neurosurgery Department Bouaké Teaching Hospital Bouaké Ivory Coast Neurosurgery Department Yamoussoukro Saint Joseph Moscatti’s Hospital Yamoussoukro Ivory Coast

Introduction: Cervical myelopathy is the most common myelopathy among people over 50 of age. Cervicosteoarthritis is the main etiology. The purpose of this work was to identify clinical factors that may influence neurological recovery in patients undergoing surgery for cervical myelopathy in our work setting. Materials and Methods: We performed a retrospective analytical study on patients operated on for cervical myelopathy at the teaching hospital of Bouake. The logistic regression model was used to identify the factors influencing post-operative neurological recovery. Results: 50 patients’ records have been enrolled in this study. The mean age of our patients was 53 years with extremes ranging from 25 to 78 years and 39 of our patients (62%) were male. The mean modified pre-operative JOA score was 11.62 versus 12.94 after the surgery. Age, sex, the number of levels operated on and the duration of the evolution of the signs showed no significant link with neurological recovery. Preoperative mild myelopathy (P = 0.0491) and post-operative functional rehabilitation (P = 0.0459) were identified as factors favouring neurological recovery after cervical myelopathy surgery. Conclusion: The good conducts of functional rehabilitation sessions as well as a mild myelopathy were the factors favouring neurological recovery.

关键词： Spinal Spondylosis Medullary Compression Myelopathy

A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： yao yao Zhijiang DAI Mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band *** topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency ***,it can be applied to transmitters that are excited by broadband *** particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design *** saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 *** results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： Yang Yang Guanxin yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Numerical investigation of non-uniform temperature fields for proppant and fluid phases in supercritical CO_(2)fracturing

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Particuology 2024年第7期90卷 149-163页

作者： Boyu Liu Jun yao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266000China

The non-uniform temperature distribution in supercritical CO_(2)(Sc-CO_(2))fracturing influences the density,viscosity,and volume expansion or shrinkage rate of Sc-CO_(2),impacting proppant *** study presents a coupled computational fluid dynamics-discrete element method and heat transfer model to examine the effects of proppant bed shape and the heat transfers of proppant-wall,proppant-fluid,and fluid-wall on the fluid and proppant temperature *** Sc-CO_(2)volume expansion is assessed under various temperature conditions by evaluating the volume-averaged Sc-CO_(2)*** factors,including proppant size,shape,thermal conductivity,concentration,temperature difference,and injection velocity,are carefully analyzed to elucidate their *** findings elucidate the existence of four distinct zones in the fluid temperature *** zone exhibits different magnitudes of temperature change under diverse conditions and undergoes dynamic transformations with the development of the proppant *** fluid-wall heat transfer and the fluid temperatures in Zones C and D are significantly subject to the fluid injection velocity(governing the heating duration),the temperature difference between fluid and formation(impacting the magnitude of heat flux),and the proppant bed shape(controlling the effective heating area).Additionally,the proppant-wall and proppant-fluid heat transfers determine the temperatures of both the proppant bed and the fluid within Zone B,showing a strong correlation with proppant thermal conductivity,proppant size,injection velocity,and temperature *** proposed coupled model provides valuable insights into the temperature distributions and flow behaviors of temperature-dependent fracturing fluids and proppants.

关键词： CFD-DEM Heat transfer Compressible fluid CO_(2)sequestration Proppant transport

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： yao Pan Xiaofeng Sun Wei Zhao Xin Li yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power

Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

Epidemiological and Diagnostic Features of Non-Traumatic Gonalgia in Adults in Bouake (Ivory Coast): About 140 Patients

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Open Journal of Rheumatology and Autoimmune Diseases 2023年第4期13卷 78-87页

作者： Kouakou Ehaulier Soh Christian Louis Sougué Charles yao konan Joe Clauvis Traore Aissata Koffi Joseph Kan Enock Goua Jean Jacques Same Bebey Francine Goupille Phillipe Daboiko Jean Claude Felix Rheumatology Department University Hospital Center Bouaké Bouaké C&#244te d’Ivoire Internal Medicine Department University Hospital Center Sour&#244 Sanou Bobo Dioulasso Burkina Faso Rheumatology Department Laquintinie Hospital Douala Cameroon Rheumatology Department University Hospital Center Tours France

Background: Non traumatic gonalgia is the second most common reason for rheumatology consultations and accounted for 15.6% of rheumatological disorders in Abidjan. Objective: The aim of this work was to study the epidemiological and diagnostic features of non-traumatic gonalgia (NTG) in a black adult population from sub-Saharan Africa. Patients and Methods: This was a five-year retrospective descriptive study (January 2014 to December 2018) of black sub-Saharan African adult patients with non traumatic gonalgia seen in the rheumatology department of the Bouake University Hospital in Côte d’Ivoire. Results: Of 2198 patients seen for rheumatological conditions, 140 had non traumatic gonalgia (6.4%). The mean age of patients was 56.13 ± 13.3 years (extremes 20 and 87 years), and the sex ratio was 0.43 (42 men and 98 women). Gonalgia without swelling was observed in 33.6% of cases. Symptoms were predominantly progressive (97.1%), chronic (82.1%) and bilateral (50%). The causes of TNM were gonarthrosis (85%), septic arthritis (7.1%), reactive arthritis (2.9%), gout (2.9%), rheumatoid arthritis (1.4%) and chondrocalcinosis (0.7%). Gonarthrosis (119/140) was bilateral in 65 patients, bi- or tri-compartmental in 83, radiographic stage (Kellgren and Lawrence) III in 80 and IV in 15. A germ was isolated in two cases of septic arthritis (methicillin-sensitive Staphylococcus aureus and Streptococcus pneumoniae). Conclusion: GNT is common in rheumatology practice in Bouake, and mainly affects women in their fifties. It is most often a chronic bilateral gonalgia, with gonarthrosis as the main etiology.

关键词： Non-Traumatic Gonalgia Gonarthrosis Bouake