Natural gas hydrates(NGH)stored in submarine deposits are a promising energy resource,Yet,the deterioration in sediment strength can trigger geological disasters due to drilling-induced hydrate dissociation.Hence,an i...Natural gas hydrates(NGH)stored in submarine deposits are a promising energy resource,Yet,the deterioration in sediment strength can trigger geological disasters due to drilling-induced hydrate dissociation.Hence,an in-depth investigation on geo physical-mechanical performance of gas hydrate-bearing sediments(GHBS)is crucial for recovery hydrates safely and efficiently.This paper provides a comprehensive assessment of the research progress on formation conditions,intrinsic properties,and mechanical responses of GHBS.The key findings have been presented:gas composition,inhibitors and promoters alter hydrate formation by modifying the thermodynamic equilibrium of temperature and pressure.Also,we identified the key determinants of porosity of GHBS and revealed the correlation between permeability,hydrate saturation,and hydrate morphology.Moreover,we highlighted the differences in mechanical behavior between hydrate-free sediments and GHBS along with their underlying mechanisms.Furthermore,we examined the methods for GHBS preparation as well as the employed test apparatuses,providing critical insights into the limitations and recommendations.By synthe-sizing data from existing literature,we conducted a comprehensive analysis of the dependence of mechanical parameters of GHBS on factors such as hydrate saturation,effective confining stress,and temperature,and dis-cussed the mechanical responses subjected to various hydrate dissociation methods.Finally,we offer a perspective for future research to focus on the micro-scale aspects,heterogeneous distribution,and long-term stability of GHBS.The discerned patterns and mechanical mechanisms are expected to guide the improvement of predictive model for geo physical-mechanical behavior of GHBS and establish a reference for developing effective strategies for recovery hydrates.展开更多
A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of li...A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of ligands might impact H_(3)BO_(3) extraction,boron isotope separation,and solvent loss,which has not been thoroughly investigated.This study initially evaluated the influence of ligand's type,pKa,and substituents on H_(3)BO_(3) extraction efficiency,as well as the impact of the B_((4))-O structure(boron is bound to four oxygen atoms)in the organic phase on isotope separation efficiency.Subsequently,by synthesizing the highly hydrophobic 2-hydroxydodecanoic acid(HYA),the extraction performance and mechanism of the TOA/HYA system were investigated.The findings highlight the superior extraction efficiency when employing di-phenolic hydroxyl,phenolic hydroxyl + carbinol hydroxyl,and alcoholic hydroxyl + carboxyl ligands compared to phenolic hydroxyl + carboxyl,phenolic hydroxyl + ethanol hydroxyl,diol hydroxyl,and dicarboxylic ligands.The organic phase anion complex,exclusively comprising the B_((4))-O structure,enhances isotope separation effectiveness.The TOA/HYA system achieves an 80%single-stage extraction efficiency for H_(3)BO_(3).H_(3)BO_(3) and HYA are extracted into the organic phase at a ratio of 1:2,with the anion complex solely containing the B_((4))-O structure.This study paves the way for the construction of novel boric acid extraction and boron isotope separation systems.展开更多
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ...Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future.展开更多
Purpose The interaction between sleep and recovery is a fundamental issue for ultra-marathoners,especially after an ultra-trail,but literatures on this matter remains are scarce.The main objectives were(1)to describe ...Purpose The interaction between sleep and recovery is a fundamental issue for ultra-marathoners,especially after an ultra-trail,but literatures on this matter remains are scarce.The main objectives were(1)to describe sleep parameters during the nights following an ultra-endurance event in amateur trail runners,(2)to evaluate the recovery kinetics,and(3)to assess the relationship between sleep parameters and recovery.Methods Nineteen race finishers were tested daily,from 10 days before to 10 days after the Ultra-Trail du Mont-Blanc^(®)(UTMB^(®)).Hooper Index(HI)was used to assess recovery and sleep parameters(total sleep time,TST and wake after sleep onset,WASO)were monitored using a wrist-worn actigraph.Results HI was higher than baseline until day 5 after the race(P<0.05)and younger athletes had a lower HI than older ones during the recovery period(P<0.001).TST was not modified by the race,but there was a WASO peak on the second night after.Positive correlations were found between WASO and muscle soreness(P<0.001)and between TST and HI(P<0.05).Conclusions In conclusion,participants needed 6 days for recovery after UTMB^(®)and younger runners seemed to recover faster than older ones.Post-race sleep quantity did not increase,but the second night was more fragmented,most likely due to muscle soreness.Correlations between sleep and recovery parameters highlighted the key role of sleep for recovery.展开更多
This work aimed at characterizing the Weissella cibaria strains isolated from Campos das Vertentes,Minas Gerais,Brazil and their antimicrobial potential.Thus,three strains of W.cibaria(W21,W25 and W42)were previously ...This work aimed at characterizing the Weissella cibaria strains isolated from Campos das Vertentes,Minas Gerais,Brazil and their antimicrobial potential.Thus,three strains of W.cibaria(W21,W25 and W42)were previously selected,and the genomes of W21 and W42 were sequenced,while that of strain W25 was already sequenced and reported.Afterwhich,we investigated the presence of genes coding for potential secondary metabolites in the genomes of the strains using the AntiSmash webtool,and located a common region coding for a putative bacteriocin identified as Bacteriocin_IIc.Then,we assessed in vitro this antimicrobial activity using the supernatant of these strains.According to the data,the strain W21,which has one transport-related gene missing from the bacteriocin operon compared to W25 and W42,likewise showed no differences in the in vitro antimicrobial test when comparing the outcomes of the three treatments(supernatant without treatment,neutralized and treated with proteinase K).Also,we compared the nucleotides and amino acids of this putative bacteriocin in the NCBI platform and there was no similarity with other so far described bacteriocin from the genus Weissella.In conclusion,two of the three Weissella strains tested in this work have the potential to produce a new bacteriocin not yet described which needs to be deeply characterized and proposed for food protection as alternatives to chemicals in foods.展开更多
Nanosized Ba_(1-x)Bi_(x)Fe_(1-x)Cu_(x)O_(3)(12–50 nm)with x values of 0,0.01,0.05,and 0.1 system was prepared using the Pechini method.Structural,morphological,surface and optical characterizations were performed for...Nanosized Ba_(1-x)Bi_(x)Fe_(1-x)Cu_(x)O_(3)(12–50 nm)with x values of 0,0.01,0.05,and 0.1 system was prepared using the Pechini method.Structural,morphological,surface and optical characterizations were performed for the prepared samples.Cubic phase was the predominant phase for the undoped BaFeO_(3)and Bi and Cu co-doped BaFeO_(3)samples.Minor phases of monoclinic Ba_(2)Fe_(2)O_(5),orthorhombic BaFe_(2)O_(4)and orthorhombic BaCO_(3)were identified for all the prepared samples.Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)sample has the lowest band gap(2.43 e V).98.1%paracetamol removal was achieved with 0.75 g/L of Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)at pH9 after 120 min.The paracetamol degradation follows the pseudo first-order kinetics.HO·is the main oxidative species responsible for the paracetamol degradation.Gas chromatography–mass spectrometry(GC–MS)analysis was performed at the end of the photocatalytic degradation experiment under optimum operating condition using Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)to explain the reaction mechanism and identify the intermediate by-products which is confirmed by ultraviolet/visible(UV/Vis)spectroscopy study at different reaction times.展开更多
This research focuses on the home health care optimization problem that involves staff routing and scheduling problems.The considered problem is an extension of multiple travelling salesman problem.It consists of find...This research focuses on the home health care optimization problem that involves staff routing and scheduling problems.The considered problem is an extension of multiple travelling salesman problem.It consists of finding the shortest path for a set of caregivers visiting a set of patients at their homes in order to perform various tasks during a given horizon.Thus,a mixed-integer linear programming model is proposed to minimize the overall service time performed by all caregivers while respecting the workload balancing constraint.Nevertheless,when the time horizon become large,practical-sized instances become very difficult to solve in a reasonable computational time.Therefore,a new Learning Genetic Algorithm for mTSP(LGA-mTSP)is proposed to solve the problem.LGA-mTSP is composed of a new genetic algorithm for mTSP,combined with a learning approach,called learning curves.Learning refers to that caregivers’productivity increases as they gain more experience.Learning curves approach is considered as a way to save time and costs.Simulation results show the efficiency of the proposed approach and the impact of learning curve strategy to reduce service times.展开更多
The outbreak of COVID-19 affected global nations and is posing serious challenges to healthcare systems across the globe.Radiologists use X-Rays or Computed Tomography(CT)images to confirm the presence of COVID-19.So,...The outbreak of COVID-19 affected global nations and is posing serious challenges to healthcare systems across the globe.Radiologists use X-Rays or Computed Tomography(CT)images to confirm the presence of COVID-19.So,image processing techniques play an important role in diagnostic procedures and it helps the healthcare professionals during critical times.The current research work introduces Multi-objective Black Widow Optimization(MBWO)-based Convolutional Neural Network i.e.,MBWOCNN technique for diagnosis and classification of COVID-19.MBWOCNN model involves four steps such as preprocessing,feature extraction,parameter tuning,and classification.In the beginning,the input images undergo preprocessing followed by CNN-based feature extraction.Then,Multi-objective Black Widow Optimization(MBWO)technique is applied to fine tune the hyperparameters of CNN.Finally,Extreme Learning Machine with autoencoder(ELM-AE)is applied as a classifier to confirm the presence of COVID-19 and classify the disease under different class labels.The proposed MBWO-CNN model was validated experimentally and the results obtained were compared with the results achieved by existing techniques.The experimental results ensured the superior results of the ELM-AE model by attaining maximum classification performance with the accuracy of 96.43%.The effectiveness of the technique is proved through promising results and the model can be applied in diagnosis and classification of COVID-19.展开更多
Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable con...Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable construction materials incorporating recycled wastes.In this scope,this work uses an experimental approach aiming at understanding the effect of incorporating Expanded Polystyrene(EPS)beads in concrete and proposing thermally improved concrete mixtures for the production of hollow blocks in Lebanese constructions by substituting fine aggregates with recycled products such as EPS in order to promote their insulating properties.Three different diameters of EPS beads(2 mm~3 mm,3 mm~4 mm and 4 mm~5 mm)are studied with different volumetric ratios(20%,40%,60%and 80%)in order to investigate the effect of EPS on the thermal properties of concrete.The results showed that the only the percentage of incorporated EPS beads impacted the thermal performance of the concrete mixtures while the EPS diameters have a negligible effect on the thermal properties of the concrete samples.展开更多
Innovative building materials are being used in building envelopes for reducing their heating and cooling needs.This paper aims to assess the thermal impact of using lightweight concrete in Lebanese building construct...Innovative building materials are being used in building envelopes for reducing their heating and cooling needs.This paper aims to assess the thermal impact of using lightweight concrete in Lebanese building constructions by pouring an 8 cm thickness of lightweight concrete on the roof and the slab and replacing traditional hollow concrete block by lightweight concrete blocks.Thermal properties of two different samples were experimentally determined:the first one(558 kg/m^(3))used for the roof and the slab and the second one(1074 kg/m^(3))used for the walls.Then numerical simulations were carried out for a Lebanese traditional detached house using the characteristics of these two samples.The thermally improved Light Weight Concrete building(LWC)was compared to a traditional Lebanese house base case(BC)using a dynamic building energy simulation tool in the four different Lebanese climate zones:coastal,mid-mountain,mountain,and inland zones.The results highlight the effectiveness of integrating LWC to building envelopes by reducing energy consumption and improving thermal comfort in both winter and summer climate conditions and in the different Lebanese climatic zones.The paper demonstrates that the use of LWC in the vertical walls replacing the traditional hollow blocks can reduce the heating needs by up to 9%and by up to 13%for cooling needs.On the other hand,adding a LWC roof screed has a very high impact on cooling and heating energy consumption,which can reach up to 74%in cooling energy savings and up to 24%in heating energy savings.展开更多
基金supported by the National Natural Science Foundation of China(No.52108401)the China Scholarship Council(202208070060).
文摘Natural gas hydrates(NGH)stored in submarine deposits are a promising energy resource,Yet,the deterioration in sediment strength can trigger geological disasters due to drilling-induced hydrate dissociation.Hence,an in-depth investigation on geo physical-mechanical performance of gas hydrate-bearing sediments(GHBS)is crucial for recovery hydrates safely and efficiently.This paper provides a comprehensive assessment of the research progress on formation conditions,intrinsic properties,and mechanical responses of GHBS.The key findings have been presented:gas composition,inhibitors and promoters alter hydrate formation by modifying the thermodynamic equilibrium of temperature and pressure.Also,we identified the key determinants of porosity of GHBS and revealed the correlation between permeability,hydrate saturation,and hydrate morphology.Moreover,we highlighted the differences in mechanical behavior between hydrate-free sediments and GHBS along with their underlying mechanisms.Furthermore,we examined the methods for GHBS preparation as well as the employed test apparatuses,providing critical insights into the limitations and recommendations.By synthe-sizing data from existing literature,we conducted a comprehensive analysis of the dependence of mechanical parameters of GHBS on factors such as hydrate saturation,effective confining stress,and temperature,and dis-cussed the mechanical responses subjected to various hydrate dissociation methods.Finally,we offer a perspective for future research to focus on the micro-scale aspects,heterogeneous distribution,and long-term stability of GHBS.The discerned patterns and mechanical mechanisms are expected to guide the improvement of predictive model for geo physical-mechanical behavior of GHBS and establish a reference for developing effective strategies for recovery hydrates.
基金supported by the National Natural Science Foundation of China(22278407,21922814,22138012,22178349)CAS Project for Young Scientists in Basic Research(YSBR-038)+1 种基金National Key Research and Development Program of China(2021YFC2901500,2022YFC2105302)Shandong Energy Institute(SEI U202306).
文摘A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of ligands might impact H_(3)BO_(3) extraction,boron isotope separation,and solvent loss,which has not been thoroughly investigated.This study initially evaluated the influence of ligand's type,pKa,and substituents on H_(3)BO_(3) extraction efficiency,as well as the impact of the B_((4))-O structure(boron is bound to four oxygen atoms)in the organic phase on isotope separation efficiency.Subsequently,by synthesizing the highly hydrophobic 2-hydroxydodecanoic acid(HYA),the extraction performance and mechanism of the TOA/HYA system were investigated.The findings highlight the superior extraction efficiency when employing di-phenolic hydroxyl,phenolic hydroxyl + carbinol hydroxyl,and alcoholic hydroxyl + carboxyl ligands compared to phenolic hydroxyl + carboxyl,phenolic hydroxyl + ethanol hydroxyl,diol hydroxyl,and dicarboxylic ligands.The organic phase anion complex,exclusively comprising the B_((4))-O structure,enhances isotope separation effectiveness.The TOA/HYA system achieves an 80%single-stage extraction efficiency for H_(3)BO_(3).H_(3)BO_(3) and HYA are extracted into the organic phase at a ratio of 1:2,with the anion complex solely containing the B_((4))-O structure.This study paves the way for the construction of novel boric acid extraction and boron isotope separation systems.
基金funded by the Czech University of Life Sciences Prague(Internal Grant Agency:A_03_22-43110/1312/3101)the Czech Science(GACR 21-27454S)。
文摘Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future.
基金We thank the organization of the Ultra Trail du Mont Blanc^(®) and the Ultra Sports Science foundation for making this study feasible.
文摘Purpose The interaction between sleep and recovery is a fundamental issue for ultra-marathoners,especially after an ultra-trail,but literatures on this matter remains are scarce.The main objectives were(1)to describe sleep parameters during the nights following an ultra-endurance event in amateur trail runners,(2)to evaluate the recovery kinetics,and(3)to assess the relationship between sleep parameters and recovery.Methods Nineteen race finishers were tested daily,from 10 days before to 10 days after the Ultra-Trail du Mont-Blanc^(®)(UTMB^(®)).Hooper Index(HI)was used to assess recovery and sleep parameters(total sleep time,TST and wake after sleep onset,WASO)were monitored using a wrist-worn actigraph.Results HI was higher than baseline until day 5 after the race(P<0.05)and younger athletes had a lower HI than older ones during the recovery period(P<0.001).TST was not modified by the race,but there was a WASO peak on the second night after.Positive correlations were found between WASO and muscle soreness(P<0.001)and between TST and HI(P<0.05).Conclusions In conclusion,participants needed 6 days for recovery after UTMB^(®)and younger runners seemed to recover faster than older ones.Post-race sleep quantity did not increase,but the second night was more fragmented,most likely due to muscle soreness.Correlations between sleep and recovery parameters highlighted the key role of sleep for recovery.
文摘This work aimed at characterizing the Weissella cibaria strains isolated from Campos das Vertentes,Minas Gerais,Brazil and their antimicrobial potential.Thus,three strains of W.cibaria(W21,W25 and W42)were previously selected,and the genomes of W21 and W42 were sequenced,while that of strain W25 was already sequenced and reported.Afterwhich,we investigated the presence of genes coding for potential secondary metabolites in the genomes of the strains using the AntiSmash webtool,and located a common region coding for a putative bacteriocin identified as Bacteriocin_IIc.Then,we assessed in vitro this antimicrobial activity using the supernatant of these strains.According to the data,the strain W21,which has one transport-related gene missing from the bacteriocin operon compared to W25 and W42,likewise showed no differences in the in vitro antimicrobial test when comparing the outcomes of the three treatments(supernatant without treatment,neutralized and treated with proteinase K).Also,we compared the nucleotides and amino acids of this putative bacteriocin in the NCBI platform and there was no similarity with other so far described bacteriocin from the genus Weissella.In conclusion,two of the three Weissella strains tested in this work have the potential to produce a new bacteriocin not yet described which needs to be deeply characterized and proposed for food protection as alternatives to chemicals in foods.
文摘Nanosized Ba_(1-x)Bi_(x)Fe_(1-x)Cu_(x)O_(3)(12–50 nm)with x values of 0,0.01,0.05,and 0.1 system was prepared using the Pechini method.Structural,morphological,surface and optical characterizations were performed for the prepared samples.Cubic phase was the predominant phase for the undoped BaFeO_(3)and Bi and Cu co-doped BaFeO_(3)samples.Minor phases of monoclinic Ba_(2)Fe_(2)O_(5),orthorhombic BaFe_(2)O_(4)and orthorhombic BaCO_(3)were identified for all the prepared samples.Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)sample has the lowest band gap(2.43 e V).98.1%paracetamol removal was achieved with 0.75 g/L of Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)at pH9 after 120 min.The paracetamol degradation follows the pseudo first-order kinetics.HO·is the main oxidative species responsible for the paracetamol degradation.Gas chromatography–mass spectrometry(GC–MS)analysis was performed at the end of the photocatalytic degradation experiment under optimum operating condition using Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)to explain the reaction mechanism and identify the intermediate by-products which is confirmed by ultraviolet/visible(UV/Vis)spectroscopy study at different reaction times.
文摘This research focuses on the home health care optimization problem that involves staff routing and scheduling problems.The considered problem is an extension of multiple travelling salesman problem.It consists of finding the shortest path for a set of caregivers visiting a set of patients at their homes in order to perform various tasks during a given horizon.Thus,a mixed-integer linear programming model is proposed to minimize the overall service time performed by all caregivers while respecting the workload balancing constraint.Nevertheless,when the time horizon become large,practical-sized instances become very difficult to solve in a reasonable computational time.Therefore,a new Learning Genetic Algorithm for mTSP(LGA-mTSP)is proposed to solve the problem.LGA-mTSP is composed of a new genetic algorithm for mTSP,combined with a learning approach,called learning curves.Learning refers to that caregivers’productivity increases as they gain more experience.Learning curves approach is considered as a way to save time and costs.Simulation results show the efficiency of the proposed approach and the impact of learning curve strategy to reduce service times.
文摘The outbreak of COVID-19 affected global nations and is posing serious challenges to healthcare systems across the globe.Radiologists use X-Rays or Computed Tomography(CT)images to confirm the presence of COVID-19.So,image processing techniques play an important role in diagnostic procedures and it helps the healthcare professionals during critical times.The current research work introduces Multi-objective Black Widow Optimization(MBWO)-based Convolutional Neural Network i.e.,MBWOCNN technique for diagnosis and classification of COVID-19.MBWOCNN model involves four steps such as preprocessing,feature extraction,parameter tuning,and classification.In the beginning,the input images undergo preprocessing followed by CNN-based feature extraction.Then,Multi-objective Black Widow Optimization(MBWO)technique is applied to fine tune the hyperparameters of CNN.Finally,Extreme Learning Machine with autoencoder(ELM-AE)is applied as a classifier to confirm the presence of COVID-19 and classify the disease under different class labels.The proposed MBWO-CNN model was validated experimentally and the results obtained were compared with the results achieved by existing techniques.The experimental results ensured the superior results of the ELM-AE model by attaining maximum classification performance with the accuracy of 96.43%.The effectiveness of the technique is proved through promising results and the model can be applied in diagnosis and classification of COVID-19.
文摘Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable construction materials incorporating recycled wastes.In this scope,this work uses an experimental approach aiming at understanding the effect of incorporating Expanded Polystyrene(EPS)beads in concrete and proposing thermally improved concrete mixtures for the production of hollow blocks in Lebanese constructions by substituting fine aggregates with recycled products such as EPS in order to promote their insulating properties.Three different diameters of EPS beads(2 mm~3 mm,3 mm~4 mm and 4 mm~5 mm)are studied with different volumetric ratios(20%,40%,60%and 80%)in order to investigate the effect of EPS on the thermal properties of concrete.The results showed that the only the percentage of incorporated EPS beads impacted the thermal performance of the concrete mixtures while the EPS diameters have a negligible effect on the thermal properties of the concrete samples.
文摘Innovative building materials are being used in building envelopes for reducing their heating and cooling needs.This paper aims to assess the thermal impact of using lightweight concrete in Lebanese building constructions by pouring an 8 cm thickness of lightweight concrete on the roof and the slab and replacing traditional hollow concrete block by lightweight concrete blocks.Thermal properties of two different samples were experimentally determined:the first one(558 kg/m^(3))used for the roof and the slab and the second one(1074 kg/m^(3))used for the walls.Then numerical simulations were carried out for a Lebanese traditional detached house using the characteristics of these two samples.The thermally improved Light Weight Concrete building(LWC)was compared to a traditional Lebanese house base case(BC)using a dynamic building energy simulation tool in the four different Lebanese climate zones:coastal,mid-mountain,mountain,and inland zones.The results highlight the effectiveness of integrating LWC to building envelopes by reducing energy consumption and improving thermal comfort in both winter and summer climate conditions and in the different Lebanese climatic zones.The paper demonstrates that the use of LWC in the vertical walls replacing the traditional hollow blocks can reduce the heating needs by up to 9%and by up to 13%for cooling needs.On the other hand,adding a LWC roof screed has a very high impact on cooling and heating energy consumption,which can reach up to 74%in cooling energy savings and up to 24%in heating energy savings.
