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Prevalence of Giardia duodenalis among dogs seized by the Center for Control of Zoonoses (CCZ) of the city of Lages, Santa Catarina, Brazil
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作者 Rosileia Marinho Quadros Paulo Henrique Exterckotter Weiss +6 位作者 Geison Willian Ezequiel Renato Batista Tamanho Geanice Lepo Marcio Rodrigues da Silva Carlos Roberto Joao da Silva Junior Flavio Antonio Pacheco de Araujo Luiz Claudio Miletti 《Health》 2013年第1期119-124,共6页
The knowledge of the epidemiology of parasitic infections in stray and domestic animals, especially of its incidence and prevalence, is fundamental to adopting effective prophylactic measures. Stray dogs play an impor... The knowledge of the epidemiology of parasitic infections in stray and domestic animals, especially of its incidence and prevalence, is fundamental to adopting effective prophylactic measures. Stray dogs play an important role in environmental contamination favoring the transmission cycle of zoonotic agents. Among the parasitic infections that affect humans, Giardia duodenalis is the most common intestinal protozoa and was designated as a re-emerging infectious disease. This study aimed to determine the prevalence of G. duodenalis in dogs siezed by the Center for Control of Zoonoses (CCZ) of the city of Lages, Santa Catarina, Brazil using two diagnostic techniques. In 357 stool samples analysed, the prevalence of G. duodenalis cysts was 5.3% (19/357) and 4.8% (17/357) detected by floatation and sedimentation techniques, respecttively. No correspondence between gender and age was found among the methods used for analyzing the infected dogs in this study. Our data suggested that two diagnostic techniques should be used in a complementary way to ensure that false negatives are not neglected. 展开更多
关键词 Giardia Duodenalis DOGS ZOONOSES Brazil
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Assessing the Impact of Gold Mining on the Quality of Water Resources in the Commune of Meguet, Burkina Faso
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作者 Issoufou Ouedraogo Samuel Lankoande +3 位作者 Yacouba Konate Boukary Sawadogo Nicolas Kagambega Martin Lompo 《Journal of Water Resource and Protection》 CAS 2024年第4期281-292,共12页
Despite its often illegal nature, artisanal gold mining in Burkina Faso contributes to the economic and social development of the country. However, the rudimentary techniques used in gold panning have a significant im... Despite its often illegal nature, artisanal gold mining in Burkina Faso contributes to the economic and social development of the country. However, the rudimentary techniques used in gold panning have a significant impact on the environment due to inappropriate practices and the use of various chemical substances. This study aims to assess the impact of artisanal gold mining on the quality of water resources in a rural community at Méguet, Burkina Faso. To this end, surface and groundwater samples were collected and analyzed at the BUMIGEB laboratory. Field results show that the waters are slightly alkaline (6.97 < pH < 8.1), weakly mineralized and conductive (124 < EC < 543 μS/cm), with temperatures ranging from 24.6˚C to 31.6˚C. In addition, trace metals (TMEs) analyzed from surface and subsurface waters show very high levels, generally deviating from the levels recommended by WHO guidelines for Burkina Faso. Trace metals contamination of water resources in the commune of Méguet is mainly due to Fe (3.78 - 11.12 mg/kg), Hg (0.03 - 0.29 mg/kg), As (0.01- 6.31 mg/kg) and Pb (0.01 - 3.8 mg/kg). This study can serve as a basis for guiding national environmental policies to protect the water resources of the Méguet mine. 展开更多
关键词 Gold Panning Water Quality Trace Metal Méguet Burkina Faso
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Optimizing wind farm layout for enhanced electricity extraction using a new hybrid PSO-ANN method
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作者 Mariam El Jaadi Touria Haidi +2 位作者 Abdelaziz Belfqih Mounia Farah Atar Dialmy 《Global Energy Interconnection》 EI CSCD 2024年第3期254-269,共16页
With the growing need for renewable energy,wind farms are playing an important role in generating clean power from wind resources.The best wind turbine architecture in a wind farm has a major influence on the energy e... With the growing need for renewable energy,wind farms are playing an important role in generating clean power from wind resources.The best wind turbine architecture in a wind farm has a major influence on the energy extraction efficiency.This paper describes a unique strategy for optimizing wind turbine locations on a wind farm that combines the capabilities of particle swarm optimization(PSO)and artificial neural networks(ANNs).The PSO method was used to explore the solution space and develop preliminary turbine layouts,and the ANN model was used to fine-tune the placements based on the predicted energy generation.The proposed hybrid technique seeks to increase energy output while considering site-specific wind patterns and topographical limits.The efficacy and superiority of the hybrid PSO-ANN methodology are proved through comprehensive simulations and comparisons with existing approaches,giving exciting prospects for developing more efficient and sustainable wind farms.The integration of ANNs and PSO in our methodology is of paramount importance because it leverages the complementary strengths of both techniques.Furthermore,this novel methodology harnesses historical data through ANNs to identify optimal turbine positions that align with the wind speed and direction and enhance energy extraction efficiency.A notable increase in power generation is observed across various scenarios.The percentage increase in the power generation ranged from approximately 7.7%to 11.1%.Owing to its versatility and adaptability to site-specific conditions,the hybrid model offers promising prospects for advancing the field of wind farm layout optimization and contributing to a greener and more sustainable energy future. 展开更多
关键词 Layout optimization Turbine placement Wind energy Hybrid optimization Particle swarm optimization Artificial neural networks Renewable energy Energy efficiency
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Characteristics of Gold Mineralization at the Baguiomo Gold Panning Site, Koudougou Region, Burkina Faso, West Africa
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作者 Pascal Ouiya Aziz Fayçal Tarnagda Martial Eric Fozing 《Open Journal of Geology》 CAS 2024年第1期1-18,共18页
The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are ... The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are located in the Kwademen-Baguiomo shear zone. This mineralization, located only a few kilometers from the Kwademen gold deposit, is uncharacterized and, together with the latter, could constitute a gold potential capable of being economically exploitable. It is in this sense that this work is carried out with a view to characterizing the gold mineralization of the Baguiomo gold panning site. To carry out this work, we have made direct field measurements, combined with microstructures, and combined all this with data from geochemical rock analysis of the basalts that are the main host formations. Geochemical data show that tholeitic basalts formed from a mantle plume that was emplaced in an oceanic plateau context. Calc-alkaline basalts and andesites are comparable to Paleoproterozoic tholeitic basalts (PTH3), which are slightly enriched in light rare earths. Fertility tests show that these basalts concentrate between 3 and 6 ppb of gold at the time of accretion, which is sufficient for remobilization of this primary gold during the Eburnian orogeny to yield a deposit of around 4 - 5 Moz. Gold mineralization is associated with pyrite crystals when the latter are disseminated in the rock mass, whereas it is associated with hematite in quartz veins concordant with S1 shear deformation. It is mainly the pyrite crystals in the pressure shadows that contain the gold grains, whose development would be synchronous with micro-shear zone reactivation during the first phase of D1<sub>B</sub> deformation. The second phase of D2<sub>B</sub> deformation, which is a crenulation or fracture schistosity, does not significantly affect the shear deformation that controls mineralization. 展开更多
关键词 Kwademen-Baguiomo Shear Zone Gold Panning Site Gold Mineralization Eburnian Orogeny
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Structural Pattern Related to Gold Mineralization in the Essakane Area (Northern Burkina Faso, West African Craton)
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作者 Marc Desire Valea Benjamin Sawadogo +3 位作者 Kalidou Traoré Urbain Wenmenga Naba Seta Benjamin Allou 《Open Journal of Geology》 CAS 2024年第9期855-879,共25页
The finite deformation structures recorded in the Essakane area, located in the northeast corner of Burkina Faso, highlight three major compressive deformation phases, successively named D1, D2, and D3. The D1 event p... The finite deformation structures recorded in the Essakane area, located in the northeast corner of Burkina Faso, highlight three major compressive deformation phases, successively named D1, D2, and D3. The D1 event phase, trending NE-SW, is characterised by P1 folds and S1 axial plane schistosity. The D2 phase trending NW-SE is characterised by folds P2, schistosity (S2) and shear (C) planes. And the D3 phase trending NNE-SSW to N-S is characterised by P3 folds, crenulation microfolds and S3 spaced schistosity. It has also been noted that gold mineralizations are mainly hosted in quartz, carbonate, pyrite, and arsenopyrite veins. Structural interpretation indicates that these veins are organized into lenticular bodies that were formed during the first two deformation phases (D1 and D2). This suggests a strong structural control typical of orogenic gold concentrations. 展开更多
关键词 Burkina Faso Essakane Shear Zone Deformation Phases Orogenic Gold
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Dehydrated Natural Feed for Cats: Influence on Apparent Digestibility Coefficient, Feces Scores, and Serum Immune, Antioxidant, and Metabolic Biomarkers
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作者 Bruno Giorgio de Oliveira Cécere Guilherme Luiz Deolindo +8 位作者 Bianca F. Bissacotti Priscila Marquezin Copetti Maria Rosa Chitolina Schetinger Bruna Klein Matheus Delamea Baldissera Thiago Pereira Ribeiro Walter Hugo Cuelho Suarez Daniel Pigatto Monteiro Aleksandro Schafer Da Silva 《Food and Nutrition Sciences》 CAS 2024年第7期594-611,共18页
The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant res... The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant response in cats. The animals were divided into two groups of seven animals each. One group received DNF, and the other consumed commercial extruded dry feed (DCF). The experiment lasted 45 days and we measured daily consumption and collected blood and feces samples. The animals in the DNF group showed greater digestibility of fiber and mineral matter than DCF. Cats in the DNF group had a higher volume of feces. DNF cats had lower leukocyte and granulocyte counts and cholesterol levels. Serum enzymatic antioxidant responses and non-enzymatic were higher in DNF cats. Cats in the DNF group showed lower serum acute phase proteins in addition to a tendency toward a higher concentration of transferrin than in the DCF group. Fecal Escherichia coli and total coliform counts of cats fed DNF were higher than DCF. We conclude that the daily consumption of cats is adequate. This feed had greater digestibility of fiber and mineral matter, in addition to an improvement in antioxidant and immunological responses. 展开更多
关键词 Alternative Feed ANTIOXIDANT Companion Animals Health
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Petrographic and Geochemical Characters of Granites of the Banfora Belt, Burkina Faso (West Africa)
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作者 Abdoulaye Ouedraogo Seta Naba Hermann Ilboudo 《International Journal of Geosciences》 CAS 2024年第9期682-697,共16页
The Banfora’s birimian greenstones belt is located in the western part of Burkina Faso (west Africa). Recent petrographic and lithogeochemical studies have highlighted plutons intruding the metasedimentary and metavo... The Banfora’s birimian greenstones belt is located in the western part of Burkina Faso (west Africa). Recent petrographic and lithogeochemical studies have highlighted plutons intruding the metasedimentary and metavolcanic series. These plutonic rocks are composed of leucogranites belonging to the so-called Ferkessedougou’s or Ferké’s batholith, granites, granodiorites, monzodiorites and quartz monzonites. From the lithogeochemical studies, these plutonic rocks have a calc-alkaline and peraluminous character. The rare earth elements spectra of the Ferké’s leucogranites let distinguished two sub-facies. One of the sub-facies is composed of quartz monzonite to granite, while the other is granitic sensu stricto. However, all these plutonic rocks were emplaced in a geodynamic context of subduction followed by collision. 展开更多
关键词 Burkina Faso Banfora Greenstones Belt PLUTONS Geodynamic Context SUBDUCTION
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Petrographic and Geochemical Characteristics of the Pouni Palaeoproterozoic Formations North of the Léo Square Degree (Burkina Faso, West Africa)
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作者 Adama Ouédraogo Yaméogo Pascal Ouiya +4 位作者 Hubert Gounwendmanaghré Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba 《Open Journal of Geology》 CAS 2024年第1期126-141,共16页
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 Palaeoproterozo... 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. 展开更多
关键词 Burkina Faso Dori Man/Léo Shield PETROGRAPHY Geochemistry Partial Melting Geotectonic Context
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Insight from Lithostructural and Aeromagnetic Data from the Léo Square Degree, Central-Western Burkina Faso
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作者 Adama Ouédraogo Yaméogo Pascal Ouiya +4 位作者 Gounwendmanaghré Hubert Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba 《Open Journal of Geology》 CAS 2024年第1期19-28,共10页
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 organisa... 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. 展开更多
关键词 Burkina Faso LINEAMENTS Belts Rocks Leo’s Leaf Granitoïd Airbornes Magnétics
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Petrographic and Geochemical Characteristics of the Granitoids in the South of Godé (North of the Square Degree of Léo-Burkina Faso, West Africa)
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作者 Adama Ouédraogo Yaméogo Hubert Gounwendmanaghré Zongo +4 位作者 Pascal Ouiya Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba 《International Journal of Geosciences》 CAS 2024年第2期106-118,共13页
South of Godé, in the central-western region of Burkina Faso, granitoids of Paleoproterozoic age are similar to those of the Man/Leo shield. This study focused on the petrographic and geochemical characteristics ... South of Godé, in the central-western region of Burkina Faso, granitoids of Paleoproterozoic age are similar to those of the Man/Leo shield. This study focused on the petrographic and geochemical characteristics of these granitoids, with the following results: 1) The tonalite that outcrops in the south-west of the study area belongs to the TTG group or first generation granitoids. They are most often ribboned at outcrop and have a geochemical signature close to that of Archean TTGs. Tonalite has a metaluminous character and the REE spectrum indicates that it may be derived from partial melting of basic magmatic rocks. 2) Biotite granites have no outcrop structure. They are weakly metaluminous to peraluminous and potassic to highly potassic. Their rare earth spectra indicate that they may be derived from the partial melting of TTG granitoids. 3) Geotectonic diagrams show that the granitoids studied to the south of Godé were emplaced in an active tectonic context similar to that of present-day subduction zones. 展开更多
关键词 Burkina Faso Godé Man/Leo Shield PETROGRAPHY Geochemistry Partial Melting Geotectonic Setting
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Kinetics of Neutralization of Polymetallic Mining Discharges from the Perkoa Zinc Deposit in Central-Western Burkina Faso
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作者 Felix Isso Bado Nicolas Kagambega Adama Yameogo 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第6期218-230,共13页
Oxidized and acidic mining discharges(pH between 4 and 5)from the Perkoa zinc mine in Burkina Faso consisting of waste rock,crusher rejects and mining tailings were sampled and used for neutralization tests with calca... Oxidized and acidic mining discharges(pH between 4 and 5)from the Perkoa zinc mine in Burkina Faso consisting of waste rock,crusher rejects and mining tailings were sampled and used for neutralization tests with calcareous dolomite(for six months).The mining discharges and the calcareous dolomite were previously characterized.Columns of 60 cm length and 15 cm diameter were used for the tests.Then,2.62 kg of calcareous dolomite was deposited on the mining discharges in each column.Two liters of deionized water are added every 15 days to each column.Samples were taken at the outlet of the columns at time intervals and then analyzed to assess the evolution of pH,electrical conductivity and contents of PHEs(Potentially Harmful Elements)over time.Following the neutralization tests on solid mining discharges,neutralization tests were also carried out on acid leachates resulting from the oxidation of these same solid mining discharges with calcareous dolomite.The results show that calcareous dolomite is very effective for the neutralization of SR(Sterile Discharges)and the precipitation of PHEs contained therein.It is also effective in buffering acidic effluents from these sterile discharges.As for other mining discharges(crusher rejects and mining residues),although calcareous dolomite is not effective in neutralizing these oxidized and acidic solid discharges,it is however effective in precipitating PHEs such as arsenic and lead.Calcareous dolomite is also effective in buffering acid leachates from these oxidized and acidic mining discharges(crusher rejects and mining tailings). 展开更多
关键词 Mining discharges zinc mine AMD(Acid Mine Drainage) DOLOMITE NEUTRALIZATION Perkoa Burkina Faso
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Geochemical Mobility Associated to Gold and Base Metal Occurrences of Mangodara Sector, in Southern Burkina Faso, Banfora Greenstone Belts (West African Craton)
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作者 Bernadin Gnamou Hermann Ilboudo +1 位作者 Wilfried Antoine Bassou Toé Sâga Sawadogo 《Open Journal of Geology》 2023年第10期1024-1053,共30页
In the Mangodara area within the Banfora greenstone belts (Baoulé-Mossi domain of the West African Craton), our study focused on geochemical assessment of the mobility of major and trace elements. Gold and base m... In the Mangodara area within the Banfora greenstone belts (Baoulé-Mossi domain of the West African Craton), our study focused on geochemical assessment of the mobility of major and trace elements. Gold and base metal occurrences are hosted in highly metamorphic felsic (metarhyolite) and intermediate (metadacite and metaandesite) formations. Common mineral assemblages made up of staurolite - kyanite - pyrophyllite are interpreted to represent the metamorphosed equivalent of aluminous hydrothermal alteration. Associated felsic and intermediate volcanic rocks are enriched in Fe<sub>2</sub>O<sub>3</sub>, K<sub>2</sub>O (metaandesite, metarhyolite) and depleted in MgO, Al<sub>2</sub>O<sub>3</sub>, CaO, P<sub>2</sub>O<sub>5</sub>, Na<sub>2</sub>O (metarhyolite) and Fe<sub>2</sub>O<sub>3</sub>, MgO, CaO (metaandesite). Al<sub>2</sub>O<sub>3</sub> depletion in mineralized kyanite-staurotide bearing metarhyolites suggests corroded minerals. Mineralized metarhyolites show enrichment in Au, Ag, Ba, Bi, Cr, Cu, Eu, La, Mo, Ni, Pb, S, Sc, V and depletion in As Sb Co, Sn, Zn while mineralized metaandesites show enrichment in Au, Ag, As, Mo, S, Sb and depletion in Co, Sn, Zn, Bi, Cr, Cu, Eu, Ni, Pb, Sc. Ba, La, V are immobile in metaandesites. Finally, Ag, As, Sn appear as geochemical vectors for gold exploration in the study area since gold mineralization is characterized by Au + Ba + Cu + Eu + La + Mo + Ni + S association in metarhyolites and Au + S + Sb + As + Ag + Bi in metaandesites. 展开更多
关键词 Geochemical Mobility Aluminous Alteration METAMORPHISM GOLD Base Metal Banfora Greenstone Belts Mangodara
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Application of four machine-learning methods to predict short-horizon wind energy
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作者 Doha Bouabdallaoui Touria Haidi +2 位作者 Faissal Elmariami Mounir Derri El Mehdi Mellouli 《Global Energy Interconnection》 EI CSCD 2023年第6期726-737,共12页
Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind e... Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind energy grows,it can be crucial to provide forecasts that optimize its performance potential.Artificial intelligence(AI)methods have risen in prominence due to how well they can handle complicated systems while enhancing the accuracy of prediction.This study explored the area of AI to predict wind-energy production at a wind farm in Yalova,Turkey,using four different AI approaches:support vector machines(SVMs),decision trees,adaptive neuro-fuzzy inference systems(ANFIS)and artificial neural networks(ANNs).Wind speed and direction were considered as essential input parameters,with wind energy as the target parameter,and models are thoroughly evaluated using metrics such as the mean absolute percentage error(MAPE),coefficient of determination(R~2),and mean absolute error(MAE).The findings accentuate the superior performance of the SVM,which delivered the lowest MAPE(2.42%),the highest R~2(0.95),and the lowest MAE(71.21%)compared with actual values,while ANFIS was less effective in this context.The main aim of this comparative analysis was to rank the models to move to the next step in improving the least efficient methods by combining them with optimization algorithms,such as metaheuristic algorithms. 展开更多
关键词 Wind Energy Prediction Support Vector Machines Decision Trees Adaptive Neuro-Fuzzy Inference Systems Artificial Neural Networks
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Lamprophyre Rocks in the Nassara Gold Deposit, Southwest Burkina Faso: Characteristics and Implication for Mining Exploration
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作者 Pascal Ouiya Adama Ouédraogo Yaméogo +1 位作者 Sâga Sawadogo Séta Naba 《Open Journal of Geology》 2023年第12期1291-1311,共21页
The lamprophyres are late dykes that cut the formations hosting the gold mineralization in the Nassara deposit. They are geographically and spatially related to most orogenic gold deposits. It is with the aim of chara... The lamprophyres are late dykes that cut the formations hosting the gold mineralization in the Nassara deposit. They are geographically and spatially related to most orogenic gold deposits. It is with the aim of characterizing them and seeing their implications for exploration that this work is carried out. To achieve our objective, petrographic studies and chemical analyses of minerals (pyroxenes, amphiboles, feldspars, chromite) and geochemical analyses of total rock were carried out. These studies have enabled us to classify the Nassara lamprophyres as calc-alkaline lamprophyres of the spessartite type. The Cr, Co, Ni and Mg enrichment of these rocks would indicate a depleted mantle source, with LILE enrichment by fluids probably related to metasomatic activity. The various diagrams show that they are depleted in HREE and enriched in LREE. The high Nb/Ta ratios in our data indicate metasomatic activity probably linked to amphibole and rutile in the mantle prior to melting. The geodynamic context of spessartite-type lamprophyres indicates a signature linked to late-orogenic to post-collisional subduction. They are late-orogenic to post-collisional lamprophyres enriched in compatible elements (Cr, Ni, Co) and display a negative Ta-Nb-Ti (TNT) anomaly. The frequent association of these lamprophyre dykes with the deposits does not indicate the source of the gold for these deposits, but rather zones of crustal permeability capable of draining hydrothermal fluids at the time of emplacement. Good mapping of lamprophyre dykes, especially in shear zones, could therefore guide prospecting and identify potential zones of hydrothermal fluid circulation. 展开更多
关键词 Nassara Calc-Alkaline Lamprophyre Metasomatic Activity LILE HREE LREE
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Alteration Typology and Geochemical Signatures of the Napélépéra Gold-Bearing Granodiorite in South-West Burkina Faso (West Africa)
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作者 Théophile Ouédraogo Sâga Sawadogo +1 位作者 Hermann Ilboudo Séta Naba 《Open Journal of Geology》 2023年第10期1162-1175,共14页
The characterization of the relationships between mineralization and hydrothermal alteration is an essential element in understanding gold deposits. In south-west Burkina Faso, the Napélépéra mineralisa... The characterization of the relationships between mineralization and hydrothermal alteration is an essential element in understanding gold deposits. In south-west Burkina Faso, the Napélépéra mineralisation, the mobility of chemical elements and alteration-mineralization relationships were studied by means of selected core drilling and geochemical analyses using ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and ICP-AES (Inductively coupled plasma atomic emission spectroscopy). The mineralised granodiorite is grey porphyroid with quartz, plagioclase, biotite and amphibole. It is metaluminous and located in the tholeiitic series. The Na<sub>2</sub>O + CaO versus Fe<sub>2</sub>O<sub>3</sub> + MgO alteration diagram divides the samples according to alteration dominance. Chloritisation and carbonation are the main alterations. There is a relationship between gold mineralisation at Napélépéra and alteration, and the paragenesis of gold + pyrite ± carbonate ± silica ± sericite is the main characteristic. Carbonation is the result of fluid input in the shear corridor of the mineralised zone. The mass balance of comparative metals in the proximal and distal zones of the mineralisation shows the absence of metals, while As, Hg, Ag and Bi are strongly enriched from the distal zone to the mineralised zone. The oxides associated with the mineralisation are mainly NaO, SrO and CaO. 展开更多
关键词 Gold Mineralization ALTERATION Mass Balance Granodiorite
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Identification of Groundwater Potential Zones in Samendeni Watershed in Sedimentary and Semi-Arid Contexts of Burkina Faso, Using Analytic Hierarchy Process (AHP) Method and GIS
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作者 Sadraki Yabre Youssouf Koussoubé +2 位作者 Sauret Élie Serge Gaëtan Nicaise Yalo Stephen Silliman 《American Journal of Climate Change》 2023年第1期172-203,共32页
Demand for water increases in Samendeni regarding the undertaken agricultural projects while pressure on surface water from global warming/evapotranspiration also increases. Thus, the need to evaluate the groundwater ... Demand for water increases in Samendeni regarding the undertaken agricultural projects while pressure on surface water from global warming/evapotranspiration also increases. Thus, the need to evaluate the groundwater potential in the catchment is crucial as alternative supplier of water and resilience to climate hazards. The AHP was performed integrating ten influencing factors such as geomorphology, geology, soil, land use/land cover (lulc), slope, rainfall, drainage density, borehole rate & depth and piezometric level to generate groundwater potential zones (GWPZs) in Samendeni watershed (4420 km<sup>2</sup>). All the factors were processed and ranged into five (5) classes. Weight was assigned to each class of thematic layer. These thematic layers were then reclassified based on the normalized weight to be used in the calculation of groundwater potential zones (GWPZ). The final output, groundwater potential map, revealed a significant groundwater potential with very good (11%), good (31%), moderate (30%), poor (20%), and very poor (8%) of proportion. The interesting (very good, good) GWPZs in the study area are mostly in the central towards the east. The poor zones in term of groundwater potential are concentrated in the upper west region of the watershed. Besides the cross-validation with the relationship between different groundwater potential zones and the wells available in the study area, the overall accuracy was estimated to 88% provided from the result of the similarity analysis where 22 out of the 25 validation wells match with the expected yield classes of GWPZs. The statistics from that validation revealed the performance of AHP method to delineate groundwater potential zones at catchment level. 展开更多
关键词 Climate Change Resilience Groundwater Potential Water Management Conjunctive Use AHP GIS Samendeni Watershed
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Experimental Evaluating of the Physical, Mechanical and Durability Properties of Natural, Recycled and Both Combined Aggregates Based Concretes
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作者 Etienne Malbila Arba A.T. Ouedraogo +3 位作者 Nicolas Kagambega Gilbert G. Nana Sié Kam David Y. K. Toguyeni 《Materials Sciences and Applications》 2023年第3期117-141,共25页
This experimental study aims at the reuse of recycled aggregates (RA), resulting from the demolition of concrete, cement block and cement mortar, in the manufacture of common construction in Burkina Faso. The RA can r... This experimental study aims at the reuse of recycled aggregates (RA), resulting from the demolition of concrete, cement block and cement mortar, in the manufacture of common construction in Burkina Faso. The RA can readily replace natural aggregates in concrete. Then five formulations of natural and recycled aggregates based concrete for characteristic strength of 25 Mpa were prepared in addition to the natural aggregates base concrete named reference concrete (BN): two types of recycled aggregates concrete (BR), three types of recycles and natural combined aggregates base concrete (BC). The properties of natural and recycled aggregates were characterized and the physical, mechanical strength and durability properties were also evaluated for all concrete specimens. All the studied concrete formulation present a density between 2000 kg/m<sup>3</sup> ≤ ρ ≥ 2600 kg/m<sup>3</sup> and an average slump of 4.9 ± 0.1 cm. The obtained results indicate that the recycled aggregates are suitable for current concrete. Two out of the five combinations studied, such as the natural (BN) and combined aggregate (BC2) based concretes satisfy the mechanical characteristics (Rc<sub>28</sub> > 25 MPa) at 28 days of age and an average absorption coefficient of 2.93% and 3.98%. The recycled aggregate based concrete (BR1, BR2) and combined aggregate based concrete (BC1), gave respective average compressive strength of 21.55 MPa, 20.50 MPa and 20.30 MPa, i.e. a difference of 13.80% to 18.80% under the characteristic strength (25 MPa) aimed at 28 days of age. Thus, the recycled aggregates are in conformity with the normative prescriptions and their use for standard concrete gives adequate physical, mechanical and durability properties for the production of the C20/25 concrete series in the common civil engineering applications. 展开更多
关键词 Concrete Demolition Waste Aggregate Recycled Aggregate Strength Water Absorption
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基于DEM的平原区人工微地貌数字提取方法探讨 被引量:9
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作者 肖飞 杜耘 +2 位作者 Parrot J F 王学雷 严翼 《地理科学》 CSCD 北大核心 2011年第6期647-653,共7页
针对江汉平原区堤垸人工微地貌,综合局部地形分析、水流模拟分析以及GIS空间分析和地统计分析方法,利用SRTM DEM数据进行微地貌自动提取研究。根据人工微地貌特点,构建一种局部地形形态分析方法来对结构线位置进行标示,并提出一种流域... 针对江汉平原区堤垸人工微地貌,综合局部地形分析、水流模拟分析以及GIS空间分析和地统计分析方法,利用SRTM DEM数据进行微地貌自动提取研究。根据人工微地貌特点,构建一种局部地形形态分析方法来对结构线位置进行标示,并提出一种流域合并的方法来进行微地貌结构线提取;进而综合上述两种方法的计算结果,提出平原区人工微地貌的组合提取方法。研究结果表明该方法可较好实现平原区垸堤人工微地貌结构线提取。 展开更多
关键词 微地貌 结构线 GIS 流域 数字提取
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利用2004年北京雨滴谱资料分析降水强度和雷达反射率因子的关系 被引量:31
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作者 刘红燕 陈洪滨 +1 位作者 雷恒池 吴玉霞 《气象学报》 CAS CSCD 北大核心 2008年第1期125-129,共5页
在北京2004年的45次降水过程中,基于DISDROMETER仪器测量的雨滴谱资料计算每次降水的强度R和雷达反射率因子Z。结果表明,不同降水过程中,雷达反射率因子Z与降水强度R的幂指数关系中的指数b和系数a是不同的,这与不同降水过程的雨滴谱分... 在北京2004年的45次降水过程中,基于DISDROMETER仪器测量的雨滴谱资料计算每次降水的强度R和雷达反射率因子Z。结果表明,不同降水过程中,雷达反射率因子Z与降水强度R的幂指数关系中的指数b和系数a是不同的,这与不同降水过程的雨滴谱分布不同密切相关。综合分析这45次降水过程中的指数b和系数a,得到指数b和系数a呈正相关。接着,分别就指数b和系数a与平均降水强度、平均雷达反射率因子、平均特征直径和雨滴平均数密度之间关系做了详细的讨论。另外,基于这一年的降水雨滴谱资料,讨论了Z-R幂指数关系中指数b和系数a的月变化特征。分析结果表明,从4月到12月系数a和指数b呈现逐月递减的年变化特征。最后,文章就12个个例的特征直径Dm的特征进行了分析。结果显示,当特征直径Dm随时间保持不变时,降水强度R和雷达反射率因子Z之间存在线性相关的关系,即当特征直径Dm为常数时,Z-R关系的指数b为1。 展开更多
关键词 DISDROMETER雨滴谱仪 降水强度 雷达反射率因子 指数关系 特征直径
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Height-to-diameter ratios with temporal and dendro/morphometric variables for Brazilian pine in south Brazil 被引量:2
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作者 Andre Felipe Hess Myrcia Minatti +7 位作者 Emanuel Arnoni Costa Luis Paulo Baldissera Schorr Gabriel Teixeira da Rosa Isadora de Arruda Souza Geedre Adriano Borsoi Veraldo Liesenberg Thiago Floriani Stepka Roberta Abatti 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期191-202,共12页
Height-to-diameter ratios(HD)are an important measure of the stability,density and competition of forest stands.It refl ects the vertical growth of the trees,the vulnerability of the forest canopy structure and infl u... Height-to-diameter ratios(HD)are an important measure of the stability,density and competition of forest stands.It refl ects the vertical growth of the trees,the vulnerability of the forest canopy structure and infl uences volumetric production.HD ratios vary according to tree size,availability of resources for growth,stand density and species composition.Data were taken from 210 trees and a regression technique of generalized linear models for the HD ratio applicable for forest structure conservation was developed.The objective of this study was to model the HD ratios of dominant and co-dominant trees of Araucaria angustifolia according to morphometric,dendrometric,annual diameter increment,stand density,and age variables in three sites in southern Brazil.The results show that the HD ratio decreases with increasing age,crown area and basal area,and increases with stand density and annual diameter increment.Accuracy of the developed equations was demonstrated by the values of deviation,Bayesian and Akaike criteria.The results are of interest to forest managers since they make decisions about silvicultural operations.Growth continuity and forest production indicate that any intervention should be directed at younger trees of smaller sizes,and that one of the main management factors for stand stability and growth is the formation of the stand and its capture of light. 展开更多
关键词 Forest management Mixed forests CONSERVATION Araucaria angustifolia
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