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A novel approach to the dynamic response analysis of Euler-Bernoulli beams resting on a Winkler soil model and subjected to impact loads

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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

On stability behaviors of 5d M-theory black objects

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Communications in Theoretical Physics 2024年第5期76卷 94-101页

作者： Adil Belhaj Abderrahim Bouhouch departement de Physique Equipe des Sciences de la matiere et du rayonnementESMaR Faculte des SciencesUniversite Mohammed V de RabatRabatMorocco

Using n=2 supergravity formalism,we investigate certain behaviors of five-dimensional black objects from the compactification of M-theory on a Calabi-Yau *** manifold has been constructed as the intersection of two homogeneous polynomials of degrees(ω+2,1)and(2,1)in a product of two weighted projective spaces given by WP^(4)(ω,1,1,1,1)×P^(1).First,we determine the allowed electric charge regions of the BPS and non BPS black holes obtained by wrapping M2-branes on appropriate two cycles in such a proposed Calabi-Yau *** that,we calculate the entropy of these solutions which takes a maximal value corresponding to ω=1 defining the ordinary projective space P^(4).For generic values of ω,we show that the non BPS states are ***,we conduct a similar study of five-dimensional black *** the allowed magnetic charge regions of the BPS and non BPS black stringy solutions derived from M5-branes on dual divisors,we calculate the tension taking a minimal value for P^(4).By determining the recombination factor,we show that the non-BPS black string states are stable in the allowed regions in the magnetic charge space.

关键词： M-theory Calabi-Yau manifolds black holes black strings stability behaviors

Exploring the effects of dietary inulin in rainbow trout fed a high‑starch,100%plant‑based diet

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Journal of Animal Science and Biotechnology 2024年第2期15卷 713-732页

作者： Raphaël defaix Jep Lokesh Laura Frohn Mickael Le Bechec Thierry Pigot Vincent Veron Anne Surget Sandra Biasutti Frederic Terrier Sandrine Skiba-Cassy Jerome Roy Stephane Panserat Karine Ricaud Universite de Pau et des Pays de L’Adour E2S UPPAINRAENUMEASaint‑Pee‑Sur‑NivelleFrance Universite de Pau et des Pays de L’Adour E2S UPPACNRSIMT Mines AlesIPREMPauFrance Universite de Pau et des Pays de L’Adour E2S UPPAIUT des Pays de l’AdourDepartement Genie BiologiqueMont de MarsanFrance.

Background High dietary carbohydrates can spare protein in rainbow trout(Oncorhynchus mykiss)but may affect growth and ***,a prebiotic,could have nutritional and metabolic effects,along with anti-inflammatory properties in teleosts,improving growth and *** tested this hypothesis in rainbow trout by feeding them a 100%plant-based diet,which is a viable alternative to fishmeal and fish oil in aquaculture *** a two-factor design,we examined the impact of inulin(2%)as well as the variation in the carbohydrates(CHO)/plant protein ratio on rainbow *** assessed the influence of these factors on zootechnical parameters,plasma metabolites,gut microbiota,production of short-chain fatty acids and lactic acid,as well as the expression of free-fatty acid receptor genes in the mid-intestine,intermediary liver metabolism,and immune markers in a 12-week feeding *** The use of 2%inulin did not significantly change the fish intestinal microbiota,but interestingly,the high CHO/protein ratio group showed a change in intestinal microbiota and in particular the beta diversity,with 21 bacterial genera affected,including Ralstonia,Bacillus,and 11 lactic-acid producing *** were higher levels of butyric,and valeric acid in groups fed with high CHO/protein diet but not with *** high CHO/protein group showed a decrease in the expression of pro-inflammatory cytokines(il1b,il8,and tnfa)in liver and a lower expression of the genes coding for tight-junction proteins in mid-intestine(tjp1a and tjp3).However,the 2%inulin did not modify the expression of plasma immune ***,inulin induced a negative effect on rainbow trout growth performance irrespective of the dietary *** With a 100%plant-based diet,inclusion of high levels of carbohydrates could be a promising way for fish nutrition in aquaculture through a protein sparing effect whereas the supplementation of 2%inulin does not appear to improve the use of CHO wh

关键词： Aquaculture Fish nutrition gut microbiota Immune markers Intermediary metabolism Inulin Prebiotic Rainbow trout Short-chain fatty acids

national Soil Organic Carbon Stocks Inventories under different Mangrove Forest Types in gabon

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Open Journal of Forestry 2024年第2期14卷 127-140页

作者： Rolf gaël Mabicka Obame neil-Yohan Musadji Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel nzigou Boucka Michel Mbina Mounguengui Claude geffroy dé partement de Phytotechnologie Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon dé partement des Sciences Fondamentales de l&#8217Ing&#233nieur Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut Agronomiques et Forestiè res Centre National des Recherches Scientifiques et Technologiques Libreville Gabon Research Centre on the durability and the Productivity of Industrial Plantations (CRdPI) Pointe Noire Republic of Congo Laboratoire Pluridisciplinaire des Sciences &#201cole Normale Sup&#233rieure Libreville Gabon Agence gabonaise d’ &#201tude et d&#8217Observation Spatiale Immeuble les Arcades Libreville Gabon dé partement de G&#233ologie Faculte des Sciences Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux de Poitiers (IC2MP) Universit&#233 de Poitiers Poitiers France

gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha−1. Among the different regions, SOC in northern zone was significantly (p p deeper layers contained higher SOC stocks (254.62 ± 128.09 MgC ha−1) than upper layers (55.42 ± 25.37 MgC ha−1). The study highlights that low deforestation rate have led to less CO2 (705.3 Mg CO2e ha−1 - 922.62 Mg CO2e ha−1) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha−1) than primary (20.33 ± 12.7 MgC ha−1), savanna and cropland (21.71 ± 15.10 MgC ha−1). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data.

关键词： Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans gabon

Multivariate Approach to Characterizing Soil Quality of gabonese’s Ferralitic Soils

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Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： neil-Yohan Musadji Rolf gaël Mabicka Obame Michel Mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude geffroy Laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France Laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Laboratoire Pluridisciplinaire des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre de Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and nemoro quality index (nQI), applied to two approaches of indicator selection: total data set (TdS) and minimum data set (MdS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of gabon. The TdS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/n ratio were retained in MdS, using principal component analysis (PCA). In the MdS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and nQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and nQI models, while 12.5% (nQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and nQI into the TdS and MdS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TdS and MdS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

Insight from Lithostructural and Aeromagnetic data from the Léo Square degree, Central-Western Burkina Faso

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Open Journal of geology 2024年第1期14卷 19-28页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya gounwendmanaghré Hubert Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta naba Unité de Formation et de Recherche en Sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso Ecole normale Supérieure (EnS)/Institut des Sciences et de Technologie (IST) Ouaga Burkina Faso Ecole Supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

This study, carried out in the Léo square degree (west-central Burkina Faso) in the Palaeoproterozoic domain of the Man/Léo ridge, aims to define the shapes and positions of granitic plutons and the organisation of deformation structures using aeromagnetic data. These data have shown that there are small sub-circular granitic bodies to the north of the granitic masses in this region, and a large sub-circular granitic body to the south, around which are other smaller granitic bodies. The lineament map shows that the deformation structures are organised along three main directions and largely form these sub-circular plutonic bodies. We suggest that the granitic plutons are coalescent, pending identification of the internal structures of these granites to further refine the geodynamic model.

关键词： Burkina Faso Lineaments Belts Rocks Leo’s Leaf granitoïd Airbornes Magnétics

Petrographic and geochemical Characteristics of the Pouni Palaeoproterozoic Formations north of the Léo Square degree (Burkina Faso, West Africa)

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Open Journal of geology 2024年第1期14卷 126-141页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya Hubert gounwendmanaghré Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta naba Unité de Formation et de Recherche en Sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso Ecole normale Supérieure (EnS) Institut des Sciences et de Technologie (IST) Ouaga Burkina Faso Ecole Supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/Leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTgs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones.

关键词： Burkina Faso dori Man/Léo Shield Petrography geochemistry Partial Melting geotectonic Context

Lateral ring compression test applied to a small caliber steel jacket:Identification of a constitutive model

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defence Technology（防务技术） 2024年第6期36卷 133-148页

作者： Yann Coget Yael demarty Christophe Czarnota Anthony Bracq Jean-Sebastien Brest Alexis Rusinek French-german Research Institute of Saint-Louis 5 Rue Du General Cassagnou68300 Saint-LouisFrance Laboratoire d'etude des Microstructures et de Mecanique des Materiaux(LEM3) CNRSUniversite de LorraineArts&Metiers ParisTechF-57000 MetzFrance

The evolution of threats and scenarios requires continuous performance improvements of ballistic protections for armed *** a modeling point of view,it is necessary to use sufficiently precise material behavior models to accurately describe the phenomena observed during the impact of a projectile on a protective *** this context,the goal of this paper is to characterize the behavior of a small caliber steel jacket by combining experimental and numerical *** experimental method is based on the lateral compression of ring specimens directly machined from the thin and small *** speeds and temperatures are considered in a quasi-static regime in order to reveal the strain rate and temperature dependencies of the tested *** Finite Element Updating Method(FEMU)is *** results are coupled with an inverse optimization method and a finite element numerical model in order to determine the parameters of a constitutive model representative of the jacket *** of the present model are verified against experimental results and a parametric study as well as a discussion on the identified material parameters are *** results indicate that the strain hardening parameter can be neglected and the behavior of the thin steel jacket can be described by a modeling without strain hardening sensitivity.

关键词： Full metal jacket ammunition Lateral ring compression Inverse identification numerical simulation

Fuzzy Henstock-Kurzweil Triple Integral on a Type 1 Quasi-Fuzzy Parallelepipedal domain

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Journal of Applied Mathematics and Physics 2024年第3期12卷 897-911页

作者： Kumwimba Seya didier Kasongo ntambwe dany Panga Lutanda grégoire Mayuke Katshongo Jean Paul Lunda ngoy Jean Pierre département de Mathématiques et Informatique Faculté des Sciences Université de Lubumbashi Lubumbashi Democratic Republic of the Congo

In this article, we propose by using the Hausdorff distance Simpson’s rule for the triple integral of a fuzzy-valued function and the error bound of this method, one of the variables of which is fuzzy. In addition, thin δ-fine partitions are introduced. The integration domain is a quasi-fuzzy parallelipiped. A numerical example is presented in order to show the application and the significance of the method.

关键词： Fuzzy-Valued Function Hausdorff distance Quasi-Fuzzy Parallelipiped Henstock Integral