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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 389-401页

作者： Adolfo Foriero Filippo Santucci de Magistris giovanni Fabbrocino département de génie civil et de génie des eaux Pavillon Adrien-PouliotUniversitéLavalQuébecCanada dipartimento di Bioscienze e Territorio Universitàdegli Studi del MoliseCampobassoItaly Construction Technologies Institute National Research CouncilITC-CNRL’AquilaItaly

This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact *** approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the *** development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are *** study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably *** particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification *** computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem.

关键词： beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor

Litho-Tectonic Architecture of the dialafara Area, Kédougou-Kéniéba Inlier, Integration of New Field data and geophysics

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Open Journal of geology 2024年第3期14卷 279-297页

作者： Mahamadou diallo Mamadou Yossi Ibrahim Méyès Coulibaly Youssouf Son Amako dolo département de géologie et Mines Ecole Nationale d’Ingénieurs Abderhamane Baba Touré (ENI-ABT) Bamako Mali Sagax Afrique S.A geophysical Surveys and Consulting Bamako Mali

The dialafara area is part of the highly endowed Kédougou-Kéniéba Inlier (KKI), West-Malian gold belt, which corresponds to a Paleoproterozoic window through the West African Craton (WAC). This study presents, first of all, an integration of geophysical data interpretation with litho-structural field reconnaissance and then proposes a new litho-structural map of the dialafara area. The dialafara area shows a variety of lithology characterized by volcanic and volcano-sedimentary units, metasediments and plutonic intrusion. These lithologies were affected by a complex superposition of structures of unequal importance defining three deformation phases (dd1 to dd3) under ductile to brittle regimes. These features permit to portray a new litho-structural map, which shows that the dialafara area presents a more complex lithological and structural context than the one presented in regional map of the KKI. This leads to the evidence that this area could be a potential site for exploration as it is situated between two world-class gold districts.

关键词： Kédougou-Kéniéba Inlier dialafara Mapping Aeromagnetic data Structure

Stable,intense supercontinuum light generation at 1 kHz by electric field assisted femtosecond laser filamentation in air

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Light(Science & Applications) 2024年第2期13卷 354-365页

作者： Yaoxiang Liu Fukang Yin Tie-Jun Wang Yuxin Leng Ruxin Li Zhizhan Xu See Leang Chin State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics and CAS Center for Excellence in Ultra-intense Laser ScienceChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina Centre d’Optique Photonique et Laser(COPL)and Département de physiquede génie physique et d’optiqueUniversitéLavalQuébecQuébecCanada

Supercontinuum(SC)light source has advanced ultrafast laser spectroscopy in condensed matter science,biology,physics,and *** to the frequently used photonic crystal fibers and bulk materials,femtosecond laser filamentation in gases is damage-immune for supercontinuum generation.A bottleneck problem is the strong jitters from filament induced self-heating at kHz repetition rate *** demonstrated stable kHz supercontinuum generation directly in air with multiple mJ level pulse *** was achieved by applying an external dC electric field to the air plasma *** pointing jitters of the 1 kHz air filament induced SC light were reduced by more than 2 *** stabilized high repetition rate laser filament offers the opportunity for stable intense SC generation and its applications in air.

关键词： intense repetition light

A neural branch-and-price for truck scheduling in cross-docks

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Science China Mathematics 2024年第6期67卷 1341-1358页

作者： Rahimeh Neamatian Monemi Shahin gelareh Nelson Maculan Wei-Kun Chen Sharkey Predictim globe Villeneuve d’Ascq59650France département R&T IUT de BéthuneUniversitéd’ArtoisBéthuneF-62000France Federal University of Rio de Janeiro COPPE-PESCRio de JaneiroRJ 21941-972Brazil School of Mathematics and Statistics Beijing Institute of TechnologyBeijing100081China

In this paper,we address the complex problem of dock-door assignment and truck scheduling within cross-docking *** is a problem that requires frequent resolution throughout the operational day,as disruptions often invalidate the optimal *** the problem's highly combinatorial nature,finding an optimal solution demands significant computational time and ***,the distribution of data across problem instances over a lengthy planning horizon remains consistently stable,with minimal concern regarding distribution *** factors collectively establish the problem as an ideal candidate for a learn-to-optimize solution *** propose a dantzig-Wolfe reformulation,solving it via both a conventional branch-and-price approach and a neural branch-and-price approach,the latter of which employs imitation ***,we introduce some classes of valid inequalities to enhance and refine the pricing problem through a branch-and-cut *** computational experiments demonstrate that this methodology is not only feasible but also presents a viable alternative to the traditional branch-and-price algorithms typically utilized for such challenges.

关键词： cross-docking MILP modeling dantzig-Wolfe decomposition graph convolutional network

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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri F.L.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

Lithostructural Control of the gold Mineralization of the douta Permit of African Star Resources (Kédougou-Kéniéba Inlier, Southeastern Senegal)

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International Journal of geosciences 2024年第4期15卷 303-333页

作者： Masse Ndour Papa Moussa Ndiaye Koffi Félix Ekra Alain Ndong Malick Faye Pierre Ndour African Star Resources Yoff Dakar S&#233n&#233gal dé partement de G&#233ologie Universit&#233 Cheikh Anta Diop Dakar S&#233n&#233gal

The douta permit of African Star Resources/Thor Explorations, located in the southeast of Senegal, in the Kédougou-Kéniéba Inlier (western part of the West African Craton), is dominated to the East by metasedimentary formations such as greywackes, shales, graphitic shales, quartzites, cherts, claystones and breccias characteristic of the dialé-daléma basin. To the West, the mafic formations of the Mako volcanic belt are the most common. Metasedimentary rocks are associated with metavolcanosedimentary terms found at the contact zones between the two (2) Birimian groups. These different geological formations are cut by mafic dolerite and gabbro sills and/or dykes, as well as quartz and microgranite veins. The douta gold project is crossed from North to South by the MTZ (Main Transcurrent Zone), generally oriented NE-SW and becoming N-S towards the North. The permit is characterized by several shear corridors. The rocks are affected by brittle, brittle-ductile to ductile deformations. The gold mineralization is hosted by a NE-trending shear corridor called the Makosa corridor (Makosa shear zone), therefore sub-parallel to the MTZ. It has a subvertical dip (75˚ to 85˚ to the NW). It is associated with a hydrothermal phase characterized by quartz-sericite-epidote-fine, disseminated pyrite and arsenopyrite ± albite ± chlorite paragenesis. These minerals testify to the existence of a low degree of metamorphism (greenschist facies, epizonal domain) in the area. However, metamorphism reaches amphibolite facies in some places, particularly in the vicinity of intrusive bodies, with the presence of hornblende (amphiboles) and plagioclase. The gold mineralization is mainly hosted by two (2) metasedimentary lithological units: meta-greywackes and shales.

关键词： douta Kédougou-Kéniéba Inlier Senegal Metasedimentary MTZ Control gold Mineralization Makosa Corridor

Numerical Simulation of Turbulent diffusion Flames of a Biogas Enriched with Hydrogen

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Fluid dynamics & Materials Processing 2024年第1期20卷 79-96页

作者： Naima Krarraz Amina Sabeur Khadidja Safer Ahmed Ouadha Laboratoire des Science et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des Carburants gazeux et de l’Environnement Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic fermentation of organic materials has the advantage of being an environmentally friendly ***,the relatively low calorific value of such gases makes their effective utilization in practical applications relatively *** present study considers the addition of hydrogen as a potential solution to mitigate this *** particular,the properties of turbulent diffusion jet flames and the related pollutant emissions are investigated numerically for different operating *** related numerical simulations are conducted by solving the RANS equations in the frame of the Reynolds Stress Model in combination with the flamelet *** effects are also taken into account and the combustion kinetics are described via the gRI-Mech 3.0 reaction *** considered hydrogen fuel enrichment spans the range from 0%to 50%in terms of *** varies between 1 and 10 *** results show that both hydrogen addition and pressure increase lead to an improvement in terms of mixing quality and have a significant effect on flame temperature and *** also reduce CO_(2) emissions but increase NOx *** NO is shown to be the predominant NO formation mechanism.

关键词： Biogas hydrogen diffusion flame turbulence NO formation route pressure

Causes of Infertility of Couples Residing in Libreville

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Advances in Reproductive Sciences 2024年第1期12卷 75-82页

作者： Opheelia Makoyo Komba Ulysse Minkobame Pamphile Assoumou Reteno Retno Elsy Ntsame Anouchka Mewi Jacques Albert Bang Ntamack Jean François Meye département de gynécologie obstétrique Université des sciences de la santé d’Owendo Libreville Gabon

Introduction: According to the World Health Organization, globally one in six people experience infertility in their lifetime. Infertility is considered as a major and global public health issue. In most cases, women bear the burden of infertility to protect the male ego. Although men and women are equally likely to have fertility problems. The aim of this study was to identify the causes of infertility of couples residing in Libreville. Patients and Methods: This was a retrospective descriptive study performed over 2 years, from 1st January 2021 to 31st december 2022. data was obtained from 162 couples attending the assisted reproduction department of the mother and child hospitals in Libreville. Statistical analysis was done using IBM SPSS Statistics version 22.0 software. Results: during the study period, 28.5% of couples could afford IVF treatment. The average for woman age was 39.1 ± 4.06 while the average age for male patients was 41.53 ± 7.08 years with minimum and maximum age of 34 et 66 years. More than half (58.6%) of female partners were employed in the public sector. Half of the male partners (50%) were employed in the private sector. The median duration of infertility was 6 years. Approximately 49.4% of couples were diagnosed with primary infertility. The most common causes of infertility in female patients were Fallopian tubes obstruction (53.2%), uterine factors (24.2%) and hormonal problems (19.6%). With regards to male factors infertility, testicular causes were predominant (53.6%). Oligoasthenoteratozoospermia were the major semen abnormalities (55.7%) found after semen evaluation. Both male and female partners were sub-fertile in 47.5% of cases. Unexplained infertility was found in 11% of couples. Conclusion: This study showed that the diagnostic of infertility faced by couples residing in Libreville should involve both male and female partner.

关键词： Epidemiology gabon Infertility

A digital twin model-based approach to cost optimization of residential community microgrids

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global Energy Interconnection 2024年第1期7卷 82-93页

作者： Mariem dellaly Sondes Skander-Mustapha Ilhem Slama-Belkhodja Université de Tunis El Manar Ecole Nationale d’Ingénieurs de TunisLR11ES15 Laboratoire de Systèmes Electriques1002TunisTunisie Université de Carthage Ecole Nationale d’Architecture et d’UrbanismeLaboratoire de Systèmes Electriques1002TunisTunisie

This paper presents a peer-to-peer community cost optimization approach based on a single-prosumer energy management *** objective is to optimize energy costs for prosumers in the community by enhancing the consumption *** study was conducted along two main *** first axis focuses on designing a digital twin for a residential community microgrid *** phase involves data collection,cleaning,exploration,and ***,it includes replicating the functionality of the real platform and validating the *** second axis involves the development of a novel approach that incorporates two distinct prosumer behaviors within the same community microgrid,while maintaining the concept of peer-to-peer energy *** without storage utilize their individual PV systems to fulfill their energy requirements and inject excess energy into a local ***,a single prosumer with a storage system actively engages in energy exchange to maximize the community’s *** is achieved by optimizing battery usage using a cost optimization *** proposed solution is validated using the developed digital twin.

关键词： Energy management system(EMS) Cost optimization digital twin Photovoltaic systems Microgrid

dynamics in the Prevalence of Insulin Resistance between 2005 and 2023 in Type 2 diabetics in South Kivu in the East of the democratic Republic of Congo: Cross-Sectional Studies

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Journal of diabetes Mellitus 2024年第1期14卷 28-40页

作者： dieudonné Masemo Bihehe Ahadi Birindwa Bwihangane Jean-Paulin Mukonkole Mbo Christian Tshongo Muhindo Michel Hermans Philippe Bianga Katchunga Hô pital général de référence de Panzi Faculté de Médecine Université Evangélique en Afrique Bukavu DR Congo département de Médecine interne Université de Kisangani Provine de la Tshopo DR Congo département de Médecine interne Université Catholique de Bukavu Bukavu DR Congo Service d’endocrinologie et de diabétologie Cliniques universitaires Saint-Luc Université Catholique de Louvain Bruxelles Belgique département de Médecine interne Cliniques Universitaires de Bukavu Université Officielle de Bukavu Bukavu DR Congo

Aim: Sub-Saharan Africa is undergoing an epidemiological transition responsible for a change in the metabolic profile in favour of insulin resistance. The aim of this study was to assess the dynamics of the prevalence of insulin resistance and associated risk factors in diabetic patients in the democratic Republic of Congo between 2005 and 2023. Method: We measured fasting blood glucose and insulin levels and looked for metabolic syndrome parameters (2009 criteria) in type 2 diabetes patients in 2005-2008 (n = 176) and in 2018-2023 (n = 303). The HOMA model was used to measure insulin sensitivity and islet β-cell secretory function. Results: Between 2005 and 2013, the trend was towards an increase in the prevalence of insulin resistance (from 13.1% to 50.8%;p Conclusion: This present study shows an increase in insulin resistance in Congolese urban areas and a persistence of atypical diabetes mellitus in Congolese rural areas, confirming the particularity of the pathophysiology of the disease in African areas currently influenced by the epidemiological transition. Further studies using an appropriate methodology are required.

关键词： Prevalence diabetes Mellitus Insulin Resistance Metabolic Syndrome South Kivu