This paper presents analysis of a cost effective methodology using remotely sensed data analysed within a geographical systems (GIS) environment for mapping out </span><span style="font-family:Verdana;&q...This paper presents analysis of a cost effective methodology using remotely sensed data analysed within a geographical systems (GIS) environment for mapping out </span><span style="font-family:Verdana;">potential habitats of anthropod vectors responsible for trypanosomiasis in northern Nigeria. These geographical locations are areas with high population of livestock in Nigeria. </span></span><span style="font-family:Verdana;">Animal Trypanosomiasis </span><span style="font-family:Verdana;">is considered as </span><span style="font-family:Verdana;">an arthropod-borne viral disease which is </span><span style="font-family:Verdana;">endemic in about 37 countries of the sub-Saharan Africa and in particular northern Nigeria. </span><span style="font-family:Verdana;">This anthropod-borne viral disease </span><span style="font-family:Verdana;">remains a threat to both humans and livestock in many communities, and the outbreak of such diseases </span><span style="font-family:Verdana;">i</span><span style="font-family:Verdana;">s shown to relate to fluctuations in the changing climate</span><span style="font-family:Verdana;"> mostly experienced whenever there are changes in global precipitation</span><span style="font-family:Verdana;"> which </span><span style="font-family:Verdana;">also relates to changes in sea surface temperatures otherwise known as </span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">El Niňo Southern Oscillations</span><span style="font-family:Verdana;">”</span><span style="font-family:Verdana;"> (ENSO). Monthly </span><span style="font-family:Verdana;">Satellite imageries in the form of Normalised Difference Vegetation Index (NDVI) at 250</span><span style="font-family:""> </span><span style="font-family:Verdana;">meters spatial resolution obtained from NASA-MODIS/CMD w</span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> subjected to principal component analysis utilizing the standardized principal components within a GIS environment and supplemented with Digital Elevation Model (DEM) data in the analysis. Results from the maps showed </span><span style="font-family:Verdana;">that </span><span style="font-family:Verdana;">pockets of probable habitats of these anthropod vectors responsible for trypanosomiasis mostly located around forest islands characterized by dry woodland and savanna, and in some cases around gallery forests and few lowland and riverine areas. This study provides baseline information for policy makers in Nigeria and other stakeholders as a cost effective measure for mapping potential habitats for anthropod vectors responsible for trypanosomiasis in Northern Nigeria. Further studies are encouraged so as to clearly understand the magnitude and actual locations of the habitat of this vector and find ways of targeting their locations for minimizing or even eradicating these vectors.展开更多
In Bangladesh,20 gas fields out of 28 produced 709.11 billion cubic feet(Bcf)through 112 wells against a vast amount of demand in the financial year 2021e22.Therefore,more gas fields need to be explored in the most pr...In Bangladesh,20 gas fields out of 28 produced 709.11 billion cubic feet(Bcf)through 112 wells against a vast amount of demand in the financial year 2021e22.Therefore,more gas fields need to be explored in the most prospective offshore part of Bangladesh.In this study,we have attempted to estimate a prospecting natural gas reserve in the Eastern Fold Belt(Block 18)consisting of Teknaf,Coral Dip,and St Martin Island as well as to develop a production view for the future.Based on the prerequisite research data collected from Petrobangla,Monte Carlo simulations were used to estimate the reserve values as Gas Initially In Place(GIIP)and Recoverable Gas Initially In Place(RGIIP)by Petroleum Engineering(PE)Essential software(version 2017.4).The results show that the estimated GIIP and RGIIP are 6145.88 billion standard cubic feet(Bscf)and 4745.5 Bscf,respectively which are quite close to the previous study.The total estimated proven natural gas of the study is 2064.4 Bcf.展开更多
Vegetation indices （Ⅵ） are one of the standard science products available from the Moderate Resolution Imaging Spectroradiometer （MODIS）. Validation of MODIS-Ⅵ products was an important prerequisite to using the...Vegetation indices （Ⅵ） are one of the standard science products available from the Moderate Resolution Imaging Spectroradiometer （MODIS）. Validation of MODIS-Ⅵ products was an important prerequisite to using these variables for global modeling. In this study, validation of the MODIS-Ⅵ products including single-day MODIS, level 2 （gridded） daily MODIS surface reflectance （MOD09）, 16-day composited MODIS （MOD13） was performed utilizing multisensor data from MODIS, Thematic Mapper （TM）, and field radiometer, for a rice-planting region in southern China. The validation approach involved scaling up independent fine-grained datasets, including ground measurement and high spatial resolution imagery, to the coarser MODIS spatial resolutions. The 16-day composited MODIS reflectance and Ⅵ matched well with the ground measurement reflectance and Ⅵ. The Ⅵ of TM and MODIS were lower than the ground Ⅵ. The results demonstrated the accuracy, reliability, and utility of the MODIS-Ⅵ products for the study region.展开更多
This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene （TCE; 500 mg/L） in synthetic groundwater. The system consisted of three reactive barriers using iron ...This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene （TCE; 500 mg/L） in synthetic groundwater. The system consisted of three reactive barriers using iron fillings as an iron-based barrier in the first column, sugarcane bagasse mixed with anaerobic sludge as an anaerobic barrier in the second column, and a biofilm coated on oxygen carbon inducer releasing material as an aerobic barrier in the third column. In order to evaluate the extent of removal of TCE and its metabolites in the aquifer down gradient of the barrier system, a fourth column filled with sand was applied. Residence time of the system was investigated by a bromide tracer test. The results showed that residence time in the column system of the control set and experimental set were 23.62 and 29.99 days, respectively. The efficiency of the three series barrier system in removing TCE was approximately 84% in which the removal efficiency of TCE by the iron filling barrier, anaerobic barrier and aerobic barrier were 42%, 16% and 25%, respectively. cis-Dichloroethylene （cis-DCE）, vinyl chloride （VC）, ethylene and chloride ions were observed as metabolites following TCE degradation. The presence of chloride ions in the effluent from the column system indicated the degradation of TCE. However, cis-DCE and VC were not fully degraded by the proposed barrier system which suggested that another remediation technology after the barrier treatment such as air sparging and adsorption by activated carbon should be conducted.展开更多
This study investigated the relationship between topographic information and trends in rainfall in Aba urban, South Eastern Nigeria. GIS data were applied to generate topographical information on?runoff characteristic...This study investigated the relationship between topographic information and trends in rainfall in Aba urban, South Eastern Nigeria. GIS data were applied to generate topographical information on?runoff characteristics, the slope, the contour, the aspect and the digital elevation model. The Mann-Kendall Trend was applied to the rainfall data to show if a monotonic increase, decrease or stability trend exist for the rainfall data of Aba metropolis for the period 2000-2010. Results showed that virtually all parts of Aba were liable to floods expect Ogbor hill axis. The flood vulnerability map indicated that 71.65% of the study area was vulnerable to flood. Rainfall trend showed a decrease in six out of the ten year period. Since within this period, flood intensity had generally remained the same, we concluded that topography, poor drainage infrastructure and non-compliance with building, planning and environmental regulations rather than rainfall trend were the key cause of flood problem in the study area.展开更多
The prevalence of unwholesome land use practices and population pressure exacerbates soil loss which is worsening the problem of sedimentation of the Kubanni dam. This study was conducted at the Kubanni drainage basin...The prevalence of unwholesome land use practices and population pressure exacerbates soil loss which is worsening the problem of sedimentation of the Kubanni dam. This study was conducted at the Kubanni drainage basin covering a spatial area of 56.7 Km2 in Samaru, Zaria, Nigeria to estimate annual soil loss using the RUSLE model. Satellite images of Landsat OLI for December 2014, 2016, 2018, February, July and November 2022;soil data, rainfall data from 2010 to 2022, and DEM of 30-meter resolution were utilized for the study. All factors of the RUSLE model were calculated for the basin using assembled data. The erosivity (R-factor) was discovered to be 553.437 MJ∙mm∙ha−1∙h−1∙yr−1. The average erodibility (K-factor) value was 0.1 Mg∙h∙h∙ha−1∙MJ−1∙mm−1∙yr−1. The Slope Length and Steepness factor (LS-factor) in the basin ranged between 0% and 13.47%. The Crop Management Factor (C-factor) values were obtained from a rescaling of the NDVI values derived for the study area and ranged from 0.26 to 0.55. Support practice (P-factors) were computed from the prevalent tillage practice in the basin and ranged from 0.27 to 0.40. The soil loss amount for the Kubanni basin was found to be 28441.482 tons∙ha−1∙yr−1, while the annual soil loss for the entire Kubanni drainage basin was found to be 49780.257 tons∙yr−1. The study has demonstrated the viability of coupling RUSLE model and Remote Sensing and Geographic Information System (GIS) techniques for the estimation of soil loss in the Kubanni drainage basin.展开更多
Concrete creep,which is characterised by the gradual,time-dependent deformation under sustained loading,remains a critical factor for structural durability,safety and long-term performance.This review synthesises key ...Concrete creep,which is characterised by the gradual,time-dependent deformation under sustained loading,remains a critical factor for structural durability,safety and long-term performance.This review synthesises key advancements in creep research,tracing its evolution from early foundational experimental studies and empirical models such as Bažant’s B3 to contemporary materials innovations and emerging computational frameworks.Novel contributions and notable developments include the integration of Finite Element Analysis(FEA),Bayesian optimisation,and fractional calculus,which have significantly improved predictive accuracy under diverse and varying environmental conditions.The study characterised the pivotal role material innovation plays in this evolution and progression,with recent focus on the development of high-performance and sustainable concretes.These advanced materials include Ultra-High-Performance Concrete(UHPC),Recycled Aggregate Concrete(RAC),Ground Granulated Blast-Furnace Slag(GGBFS)modified concrete,Rice Husk Ash(RHA)composites,and nano-modified concretes,all aimed at enhancing creep resistance and sustainability.The study also examines the influence of temperature,humidity,and sustained stress on creep behaviour,highlighting the need for robust multiscale models.Emerging trends,such as artificial intelligence,mesoscopic modelling,and eco-efficient materials,are identified as transformative tools for future research and applications.By bridging historical insights with modern innovations,this work provides a strategic framework for the design of resilient,durable,and sustainable infrastructure systems in the face of evolving performance demands and environmental challenges.展开更多
文摘This paper presents analysis of a cost effective methodology using remotely sensed data analysed within a geographical systems (GIS) environment for mapping out </span><span style="font-family:Verdana;">potential habitats of anthropod vectors responsible for trypanosomiasis in northern Nigeria. These geographical locations are areas with high population of livestock in Nigeria. </span></span><span style="font-family:Verdana;">Animal Trypanosomiasis </span><span style="font-family:Verdana;">is considered as </span><span style="font-family:Verdana;">an arthropod-borne viral disease which is </span><span style="font-family:Verdana;">endemic in about 37 countries of the sub-Saharan Africa and in particular northern Nigeria. </span><span style="font-family:Verdana;">This anthropod-borne viral disease </span><span style="font-family:Verdana;">remains a threat to both humans and livestock in many communities, and the outbreak of such diseases </span><span style="font-family:Verdana;">i</span><span style="font-family:Verdana;">s shown to relate to fluctuations in the changing climate</span><span style="font-family:Verdana;"> mostly experienced whenever there are changes in global precipitation</span><span style="font-family:Verdana;"> which </span><span style="font-family:Verdana;">also relates to changes in sea surface temperatures otherwise known as </span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">El Niňo Southern Oscillations</span><span style="font-family:Verdana;">”</span><span style="font-family:Verdana;"> (ENSO). Monthly </span><span style="font-family:Verdana;">Satellite imageries in the form of Normalised Difference Vegetation Index (NDVI) at 250</span><span style="font-family:""> </span><span style="font-family:Verdana;">meters spatial resolution obtained from NASA-MODIS/CMD w</span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> subjected to principal component analysis utilizing the standardized principal components within a GIS environment and supplemented with Digital Elevation Model (DEM) data in the analysis. Results from the maps showed </span><span style="font-family:Verdana;">that </span><span style="font-family:Verdana;">pockets of probable habitats of these anthropod vectors responsible for trypanosomiasis mostly located around forest islands characterized by dry woodland and savanna, and in some cases around gallery forests and few lowland and riverine areas. This study provides baseline information for policy makers in Nigeria and other stakeholders as a cost effective measure for mapping potential habitats for anthropod vectors responsible for trypanosomiasis in Northern Nigeria. Further studies are encouraged so as to clearly understand the magnitude and actual locations of the habitat of this vector and find ways of targeting their locations for minimizing or even eradicating these vectors.
文摘In Bangladesh,20 gas fields out of 28 produced 709.11 billion cubic feet(Bcf)through 112 wells against a vast amount of demand in the financial year 2021e22.Therefore,more gas fields need to be explored in the most prospective offshore part of Bangladesh.In this study,we have attempted to estimate a prospecting natural gas reserve in the Eastern Fold Belt(Block 18)consisting of Teknaf,Coral Dip,and St Martin Island as well as to develop a production view for the future.Based on the prerequisite research data collected from Petrobangla,Monte Carlo simulations were used to estimate the reserve values as Gas Initially In Place(GIIP)and Recoverable Gas Initially In Place(RGIIP)by Petroleum Engineering(PE)Essential software(version 2017.4).The results show that the estimated GIIP and RGIIP are 6145.88 billion standard cubic feet(Bscf)and 4745.5 Bscf,respectively which are quite close to the previous study.The total estimated proven natural gas of the study is 2064.4 Bcf.
基金Project supported by the National Natural Science Foundation of China (No. 40171065)the National High Technology Research and Development Program (863 Program) of China (No. 2002AA243011)
文摘Vegetation indices （Ⅵ） are one of the standard science products available from the Moderate Resolution Imaging Spectroradiometer （MODIS）. Validation of MODIS-Ⅵ products was an important prerequisite to using these variables for global modeling. In this study, validation of the MODIS-Ⅵ products including single-day MODIS, level 2 （gridded） daily MODIS surface reflectance （MOD09）, 16-day composited MODIS （MOD13） was performed utilizing multisensor data from MODIS, Thematic Mapper （TM）, and field radiometer, for a rice-planting region in southern China. The validation approach involved scaling up independent fine-grained datasets, including ground measurement and high spatial resolution imagery, to the coarser MODIS spatial resolutions. The 16-day composited MODIS reflectance and Ⅵ matched well with the ground measurement reflectance and Ⅵ. The Ⅵ of TM and MODIS were lower than the ground Ⅵ. The results demonstrated the accuracy, reliability, and utility of the MODIS-Ⅵ products for the study region.
基金the travel funds from Rajamangala University of Technology-Isan-Kalasin Campus and the GraduateSchool,Khon Kaen University
文摘This study attempted to construct a three series barrier system to treat high concentrations of trichloroethylene （TCE; 500 mg/L） in synthetic groundwater. The system consisted of three reactive barriers using iron fillings as an iron-based barrier in the first column, sugarcane bagasse mixed with anaerobic sludge as an anaerobic barrier in the second column, and a biofilm coated on oxygen carbon inducer releasing material as an aerobic barrier in the third column. In order to evaluate the extent of removal of TCE and its metabolites in the aquifer down gradient of the barrier system, a fourth column filled with sand was applied. Residence time of the system was investigated by a bromide tracer test. The results showed that residence time in the column system of the control set and experimental set were 23.62 and 29.99 days, respectively. The efficiency of the three series barrier system in removing TCE was approximately 84% in which the removal efficiency of TCE by the iron filling barrier, anaerobic barrier and aerobic barrier were 42%, 16% and 25%, respectively. cis-Dichloroethylene （cis-DCE）, vinyl chloride （VC）, ethylene and chloride ions were observed as metabolites following TCE degradation. The presence of chloride ions in the effluent from the column system indicated the degradation of TCE. However, cis-DCE and VC were not fully degraded by the proposed barrier system which suggested that another remediation technology after the barrier treatment such as air sparging and adsorption by activated carbon should be conducted.
文摘This study investigated the relationship between topographic information and trends in rainfall in Aba urban, South Eastern Nigeria. GIS data were applied to generate topographical information on?runoff characteristics, the slope, the contour, the aspect and the digital elevation model. The Mann-Kendall Trend was applied to the rainfall data to show if a monotonic increase, decrease or stability trend exist for the rainfall data of Aba metropolis for the period 2000-2010. Results showed that virtually all parts of Aba were liable to floods expect Ogbor hill axis. The flood vulnerability map indicated that 71.65% of the study area was vulnerable to flood. Rainfall trend showed a decrease in six out of the ten year period. Since within this period, flood intensity had generally remained the same, we concluded that topography, poor drainage infrastructure and non-compliance with building, planning and environmental regulations rather than rainfall trend were the key cause of flood problem in the study area.
文摘The prevalence of unwholesome land use practices and population pressure exacerbates soil loss which is worsening the problem of sedimentation of the Kubanni dam. This study was conducted at the Kubanni drainage basin covering a spatial area of 56.7 Km2 in Samaru, Zaria, Nigeria to estimate annual soil loss using the RUSLE model. Satellite images of Landsat OLI for December 2014, 2016, 2018, February, July and November 2022;soil data, rainfall data from 2010 to 2022, and DEM of 30-meter resolution were utilized for the study. All factors of the RUSLE model were calculated for the basin using assembled data. The erosivity (R-factor) was discovered to be 553.437 MJ∙mm∙ha−1∙h−1∙yr−1. The average erodibility (K-factor) value was 0.1 Mg∙h∙h∙ha−1∙MJ−1∙mm−1∙yr−1. The Slope Length and Steepness factor (LS-factor) in the basin ranged between 0% and 13.47%. The Crop Management Factor (C-factor) values were obtained from a rescaling of the NDVI values derived for the study area and ranged from 0.26 to 0.55. Support practice (P-factors) were computed from the prevalent tillage practice in the basin and ranged from 0.27 to 0.40. The soil loss amount for the Kubanni basin was found to be 28441.482 tons∙ha−1∙yr−1, while the annual soil loss for the entire Kubanni drainage basin was found to be 49780.257 tons∙yr−1. The study has demonstrated the viability of coupling RUSLE model and Remote Sensing and Geographic Information System (GIS) techniques for the estimation of soil loss in the Kubanni drainage basin.
文摘Concrete creep,which is characterised by the gradual,time-dependent deformation under sustained loading,remains a critical factor for structural durability,safety and long-term performance.This review synthesises key advancements in creep research,tracing its evolution from early foundational experimental studies and empirical models such as Bažant’s B3 to contemporary materials innovations and emerging computational frameworks.Novel contributions and notable developments include the integration of Finite Element Analysis(FEA),Bayesian optimisation,and fractional calculus,which have significantly improved predictive accuracy under diverse and varying environmental conditions.The study characterised the pivotal role material innovation plays in this evolution and progression,with recent focus on the development of high-performance and sustainable concretes.These advanced materials include Ultra-High-Performance Concrete(UHPC),Recycled Aggregate Concrete(RAC),Ground Granulated Blast-Furnace Slag(GGBFS)modified concrete,Rice Husk Ash(RHA)composites,and nano-modified concretes,all aimed at enhancing creep resistance and sustainability.The study also examines the influence of temperature,humidity,and sustained stress on creep behaviour,highlighting the need for robust multiscale models.Emerging trends,such as artificial intelligence,mesoscopic modelling,and eco-efficient materials,are identified as transformative tools for future research and applications.By bridging historical insights with modern innovations,this work provides a strategic framework for the design of resilient,durable,and sustainable infrastructure systems in the face of evolving performance demands and environmental challenges.
