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Microsystems & Nanoengineering 2018年第1期4卷 128-140页

作者： Yingxian Lu Frédéric Marty dimitri galayko Jean-Marc Laheurte Philippe Basset UniversitéParis-Est ESYCOM(EA2552)CNAMESIEE Paris and UPEMLVNoisyle-Grand 93162France Sorbonne Université LIP6 labCIAN groupJussieu campusParis 75005France UniversitéParis-Est ESYCOM(EA2552)CNAMESIEE Paris and UPEMLVMarne-la-Vallée 77420France

A MEMS electrostatic kinetic energy harvester(e-KEH)of about 1 cm2,working at ultralow frequency(1–20 Hz),without any supported additional mass on its mobile electrode,and working even without a vacuum environment is *** prototype is especially suitable for environments with abundant low frequency motions such as wearable *** proposed e-KEH consists of a capacitor with a finger-teeth interdigited comb *** greatly reduces the air damping effect,and thus the capacitance variation remains important regardless of the presence of *** the new design,the energy transduced per cycle of excitation is no less than 33 times higher than the classic design within 10–40 Hz/2 g_(peak),while is 85 times higher at 15 Hz/2 g_(peak).An enclosed miniature ball combined with non-linear stoppers enables the oscillation of the movable electrode through impact-based frequency up-conversion mechanism,which is also improved by the low air *** to this new design,a higher efficiency than the classic gap-closing comb structure is obtained,as a larger range of working frequency(1–180 Hz)in air.A maximum energy conversion of 450 nJ/cycle is obtained with a bias voltage of 45 V and an acceleration of 11 Hz,3 g_(peak).Working with a diode AC-DC rectifier,the proposed KEH is able to support up to 3 RFID communications within 16 s while operated at 11 Hz,3 g_(peak).

关键词： autonomous kinetic electrostatic

Simulation and Performance Analysis of Six Types of Sun Tracker Approaches:A Comparative Analysis for Solar Concentrating Technology Application at Burkina Faso

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Journal of Energy and Power Engineering 2024年第1期18卷 1-8页

作者： Stanislas Sanfo Serge dimitri Bazyomo Tizane Daho Abdoulaye Ouedraogo Laboratoire de Physique et de Chimie de l’Environnement(LPCE) Departement de PhysiqueUnitéde Formation et de Recherche en Sciences Exactes et AppliquéesUniversitéJoseph KI-ZERBOOuagadougouBP 7021Burkina Faso Laboratory of Thermal and Renewable Energies Department of Physics Unit of Training and Research on Exact and Applied SciencesUniversity Joseph KI-ZERBOOuagadougouBP 7021Burkina Faso Laboratoire Recherche Développement(LARED) Universitéde OuahigouyaBurkina Faso

Modelization equations of six approaches for tracking the sun are recalled and used to evaluate the constraints and performances to which they lead *** geographical study case is taken for the specific latitude of 12 North that is a good matching with the location of the country of Burkina *** decisive periods were locally established in order to consider the different travels of the sun on sky during one *** work presents some technical data which facilitates the choice of sun tracking approaches with concern of a concentrator limits such as its angle of acceptance,its motion control card interpolation model,or its minimum irradiation level for energy conversion effectiveness.

关键词： Solar radiation sun tracker Burkina Faso experimental data

Contribution of Satellite Observations in the Optical and Microphysical Characterization of Aerosols in Burkina Faso, West Africa

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Atmospheric and Climate Sciences 2024年第1期14卷 154-171页

作者： Nébon Bado Serge dimitri Bazyomo Germain Wende Pouiré Ouedraogo Bruno Korgo Mamadou Simina Dramé Florent P. Kieno Sié Kam Laboratoire d’Energies Thermiques Renouvelables (L.E.T.RE) Université Joseph KI ZERBO Ouaga Burkina Faso Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon-Fongang Université Cheikh Anta DIOP Dakar-Fann Sénégal Institute of Mathematics and Physical Sciences University of Abomey-Calavi Porto-Novo Benin

In this work, we proceed to an optical and microphysical analysis of the observations reversed by the MODIS, SeaWiFS, MISR and OMI sensors with the aim of proposing the best-adapted airborne sensor for better monitoring of aerosols in Burkina Faso. To this end, a comparison of AOD between satellite observations and in situ measurements at the Ouagadougou site reveals an underestimation of AERONET AOD except for OMI which overestimates them. Also, an inter-comparison done based on the linear regression line representation shows the correlation between the aerosol models incorporated in the airborne sensor inversion algorithms and the aerosol population probed. This can be seen through the correlation coefficients R which are 0.84, 0.64, 0.55 and 0.054 for MODIS, SeaWiFS, MISR and OMI respectively. Furthermore, an optical analysis of aerosols in Burkina Faso by the MODIS sensor from 2001 to 2016 indicates a large spatial and temporal variability of particles strongly dominated by desert dust. This is corroborated by the annual and seasonal cycles of the AOD at 550 nm and the Angström coefficient measured in the spectral range between 412 nm and 470 nm. A zoom on a few sites chosen according to the three climatic zones confirms the majority presence of mineral aerosols in Burkina Faso, whose maxima are observed in spring and summer.

关键词： AERONET Airborne Sensors Aerosol Optical and Microphysical Properties

Surgical Management of Lumbar Spinal Canal Stenosis with Instrumentation at the Yaounde Central Hospital: Comparison of Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion

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Open Journal of Modern Neurosurgery 2024年第3期14卷 179-189页

作者： Orlane Toto Ndome Nassourou Oumarou Haman dimitri Fogue Jean Bruno Ndoumou Ronaldo Fonju Anu Indira Baboke Vincent De Paul Djientcheu Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Neurosurgery Douala General Hospital Douala Cameroon Faculty of Medicine and Biomedical Sciences University of Yaounde 1 Yaounde Cameroon Department of Neurosurgery Yaounde General and Central Hospitals Yaounde Cameroon Cameroon Academy of Young Scientists Yaounde Cameroon

Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed comparing the clinical effectiveness of unilateral versus bilateral fixation in the surgical management of lumbar spinal canal stenosis. Objective: Evaluate the impact on quality of life and clinical efficacy of unilateral spondylodesis compared to bilateral spondylodesis in the surgical management of lumbar spinal canal stenosis at the Yaounde Central Hospital. Methods: This was a retrospective descriptive cross-sectional study for a period of 4 years, from June 2015 to June 2019. It involved all patients operated for lumbar canal stenosis and who underwent spondylodesis or spinal fusion at the neurosurgery department of the Yaounde Central Hospital. Results: A total of 68 participants were recruited during our study period. 32 (47%) of the study population were in the 50 - 60 age group, with a mean age of 56.98 years ranging from 41 to 75 years. Females, housewives and farmers were the most affected. In our study, 72% of patients had unilateral spondylodesis and 28% had bilateral fusion. Preoperatively, 71% of patients had insurmountable pain, refractory to medical treatment. At 3 months postoperatively, 73.7% of patients with bilateral setup had moderate pain compared to 69% of those with unilateral setup. At 6 months postoperatively, 79% of patients with bilateral fusion had mild pain compared to 82% of patients with unilateral setup. At 1 year postoperatively, all patients had mild pain. Preoperatively, 66.2% of patients were unable to walk and 19.1% of patients were bedridden according to the Oswestry score. At 3 months postoperatively, 10.2% of patients with unilateral setup were unable to walk compared to 10.5% of patients with bilateral fixation, while 67.3% of patients with unilateral fixation had moderate disability compared to 52.6% of patient

关键词： Lumbar Spinal Canal Stenosis Instrumentation Surgery Quality of Life

Equation of state for boron nitride along the principal Hugoniot to 16 Mbar

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Matter and Radiation at Extremes 2024年第5期9卷 77-86页

作者： Huan Zhang Yutong Yang Weimin Yang Zanyang Guan Xiaoxi Duan Mengsheng Yang Yonggang Liu Jingxiang Shen Katarzyna Batani Diluka Singappuli Ke Lan Yongsheng Li Wenyi Huo Hao Liu Yulong Li Dong Yang Sanwei Li Zhebin Wang Jiamin Yang Zongqing Zhao Weiyan Zhang Liang Sun Wei Kang dimitri Batani National Key Laboratory of Plasma Physics Laser Fusion Research CenterChina Academy of Engineering PhysicsMianyang 621900China HEDPS Center for Applied Physics and Technologyand College of PhysicsPeking UniversityBeijing 100871China HEDPS Center for Applied Physics and Technologyand School of EngineeringPeking UniversityBeijing 100871China Institute of Plasma Physics and Laser Microfusion Hery 2301-497 WarszawaPoland Universitéde Bordeaux CNRSCEACELIA(Centre Lasers Intenses et Applications)UMR 5107F-33405 TalenceFrance Institute of Applied Physics and Computational Mathematics Beijing 100094China

The thermodynamic properties of boron nitride under extreme pressures and temperatures are of great interest and importance for materials science and inertial confinement fusion physics,but they are poorly understood owing to the challenges of performing experiments and realizing ab initio ***,we report the first shock Hugoniot data on hexagonal boron nitride at pressures of 5–16 Mbar,using hohlraum-driven shock waves at the SGIII-p laser facility in *** density functional theory molecular dynamics calculations closely match experimental data,validating the equations of state for modeling the shock response of boron nitride and filling a crucial gap in the knowledge of boron nitride properties in the region of multi-Mbar pressures and eV *** results presented here provide fundamental insights into boron nitride under the extreme conditions relevant to inertial confinement fusion,hydrogen–boron fusion,and high-energy-density physics.

关键词： boron Hugoniot extreme

Multi-Scale Approach for Gold Targeting in Côte d’Ivoire Paleoproterozoic Rocks

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Open Journal of Geology 2024年第2期14卷 155-176页

作者： Martial Pohn Koffi Adingra Yao Augustin Koffi N’guessan Nestor Houssou Zié Ouattara Tokpa Kakeu Lionel-dimitri Boya Marc Ephrem Allialy Training and Research Unit in Earth Sciences and Mineral Resources Laboratory of Geology Mineral and Energy Resources University Felix HOUPHOU&#203T-BOIGNY Abidjan C&#244te d’Ivoire Training and Research Unit in Geological Sciences and Mining Department of Geology and Material Man University Man C&#244te d’Ivoire

The aim of this study is to contribute to better targeting of gold prospecting areas using geospatial information. To this end, 3 mining sites were selected for the study. They are: the Sénoufo belt (Barrick Gold mine), the Yaouré complex (Perseus Mining mine) and the South Fetêkro belt (Bonikro, Hiré and Agbaou mines). For this study, a multi-scale approach was carried out at regional, mine and microscopic levels. At the regional scale, a comparative analysis of 1:200,000 scale geological maps revealed that 3 main lithologies are regularly repeated on and around the various mining sites. These are: undifferentiated volcanics, metagranodiorites and metasiltites dominated by meta-arenites. Most of these lithologies are affected by undifferentiated faults generally oriented NE-SW, N-S, ENE-WSW and WNW-ESE. In addition, gold and manganese occurrences are present on all the sites studied. At the mine scale, radarsat-1 images processing indicate that the main mining sites are generally located near or at the intersection of lineaments-oriented NE-SW or N-S on the one hand and E-W or ENE-WSW or WNW-ESE or again NW-SE on the other. These mines are also located at the interface between zones of high and low lineament density. At the microscopic scale, petrographic studies of undifferentiated volcanic samples from the various sites indicate that they consist of andesites, meta-andesites and tuffs.

关键词： Gold Targeting Undifferentiated Volcanics Mineral Occurrences Lineaments Côte d’Ivoire

Multiagent Reinforcement Learning:Rollout and Policy Iteration

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 249-272页

作者： dimitri Bertsekas the Arizona State University(ASU) TempeAZ 85281 USAand also with Massachusetts Institute of Technology(MIT)CambridgeMA 02139

We discuss the solution of complex multistage decision problems using methods that are based on the idea of policy iteration(PI),i.e.,start from some base policy and generate an improved *** is the simplest method of this type,where just one improved policy is *** can view PI as repeated application of rollout,where the rollout policy at each iteration serves as the base policy for the next *** contrast with PI,rollout has a robustness property:it can be applied on-line and is suitable for on-line ***,rollout can use as base policy one of the policies produced by PI,thereby improving on that *** is the type of scheme underlying the prominently successful Alpha Zero chess *** this paper we focus on rollout and PI-like methods for problems where the control consists of multiple components each selected(conceptually)by a separate *** is the class of multiagent problems where the agents have a shared objective function,and a shared and perfect state *** on a problem reformulation that trades off control space complexity with state space complexity,we develop an approach,whereby at every stage,the agents sequentially(one-at-a-time)execute a local rollout algorithm that uses a base policy,together with some coordinating information from the other *** amount of total computation required at every stage grows linearly with the number of *** contrast,in the standard rollout algorithm,the amount of total computation grows exponentially with the number of *** the dramatic reduction in required computation,we show that our multiagent rollout algorithm has the fundamental cost improvement property of standard rollout:it guarantees an improved performance relative to the base *** also discuss autonomous multiagent rollout schemes that allow the agents to make decisions autonomously through the use of precomputed signaling information,which is sufficient to maintain the c

关键词： Dynamic programming multiagent problems neuro-dynamic programming policy iteration reinforcement learning rollout

Peripheral Facial Paralysis in People Living with Human Immunodeficiency Virus (HIV)

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第3期13卷 168-177页

作者： Lekassa Pierrette Andjock Nkouo Yves Christian Mouinga Abayi Alex Davy Assoumou Ada Prudence BiyeNgoghe Prudence Ngoma Manfoumbi Albert Brice Manfoumbi Manfoumbi Kévin dimitri Miloundja Jerome Nzouba Léon ENT and CFS Department Omar Bongo Ondimba Army Instruction Hospital Libreville Gabon Department of Surgery and Surgical Specialties University of Health Sciences Owendo Gabon ENT and CFS Department Yaound&#233 General Hospital Yaound&#233 Cameroon Ophthalmology Department Omar Bongo Ondimba Army Instruction Hospital Libreville Gabon Ophthalmology Department Owendo University Hospital Center Libreville Gabon Internal Medicine Department Omar Bongo Ondimba Army Instruction Hospital Libreville Gabon

Introduction: Peripheral facial palsy (PFP) is a frequent reason for ENT consultations. It is a common complication of human immunodeficiency virus (HIV) infection. The aim of this study was to describe the diagnostic and therapeutic aspects and to establish the correlation between PFP and HIV in our context. Patients and Method: This was a retrospective descriptive study conducted in the ENT and CFS department of the HIAOBO, covering the medical records of patients hospitalized for taking a PFP on HIV terrain from January 1, 2016 to December 31, 2020. Results: The study involved 17 patients, 10 men (59%) and 7 women (41%), a sex ratio of 1.4. The average age was 39 years with the extremes of 11 and 69 years. Shopkeepers reported 9 cases (53%). The reason for consultation was facial asymmetry in 11 cases (100%). The delay in consultation during the first week was 82.4%. Clinical signs were unilateral facial asymmetry, the opening of the palpebral fissure and lacrimation. All patients received medical treatment for PFP and HIV. Evolution was favorable, with complete recovery and no sequelae in 82.4% of cases. Surgery was performed in one case. Conclusion: PFPs are common in HIV infection. Diagnosis is clinical and management is multidisciplinary. Progression depends on the length of time taken to treat the disease.

关键词： Peripheral Facial Paralysis HIV HIAOBO

Feature-Based Aggregation and Deep Reinforcement Learning:A Survey and Some New Implementations

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 1-31页

作者： dimitri P.Bertsekas the Department of Electrical Engineering and Computer Science and the Laboratory for Information and Decision SystemsMassachusetts Institute of Technology

In this paper we discuss policy iteration methods for approximate solution of a finite-state discounted Markov decision problem, with a focus on feature-based aggregation methods and their connection with deep reinforcement learning schemes. We introduce features of the states of the original problem, and we formulate a smaller "aggregate" Markov decision problem, whose states relate to the features. We discuss properties and possible implementations of this type of aggregation, including a new approach to approximate policy iteration. In this approach the policy improvement operation combines feature-based aggregation with feature construction using deep neural networks or other calculations. We argue that the cost function of a policy may be approximated much more accurately by the nonlinear function of the features provided by aggregation, than by the linear function of the features provided by neural networkbased reinforcement learning, thereby potentially leading to more effective policy improvement.

关键词： Reinforcement learning dynamic programming Markovian decision problems aggregation feature-based architectures policy iteration deep neural networks rollout algorithms

Autoimmune pancreatitis and pancreatic cancer:Epidemiological aspects and immunological considerations

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World Journal of Gastroenterology 2021年第25期27卷 3825-3836页

作者： dimitri Poddighe Department of Medicine School of MedicineNazarbayev UniversityNur-Sultan 010000Kazakhstan Department of Pediatrics National Research Institute for Maternal and Child Health(NRCMCH)University Medical Center(UMC)Nur-Sultan 010000Kazakhstan

Ordinary chronic pancreatitis is a well-known risk factor for pancreatic cancer,whereas such an association with autoimmune pancreatitis(AIP)is widely *** to the rarity of the latter disorder,there are few specific clinical and epidemiological studies investigating the relation between AIP and pancreatic cancer,which do not seem to support ***,these studies are affected by several limitations and,therefore,a link between AIP(and,specifically,type 1 AIP)and pancreatic cancer cannot be ruled out definitively on this ***,several immunopathological aspects of type 1 AIP and,in general,immunoglobulin G4-related disease can create an immunological context that may impair the tumoral immunosurveillance and promote the pancreatic carcinogenesis and its *** detail,Th2 immunological dominance,type 2 macrophage polarization and basophil infiltration observed in type 1 AIP,may play a permissive role in creating a favorable immunological environment for pancreatic carcinogenesis,in addition to the immunosuppressive therapies that can be used in these patients.

关键词： Autoimmune pancreatitis Chronic pancreatitis Pancreatic cancer Immunoglobulin G4-related disease Epidemiology Immunology Basophils Macrophages Th2 cells Systemic lupus erythematosus