Sand barriers are the most widely used mechanical implements for wind-blown sand control and desertification prevention.However,there is no standard quantitative cost analysis of the sizes and materials required for s...Sand barriers are the most widely used mechanical implements for wind-blown sand control and desertification prevention.However,there is no standard quantitative cost analysis of the sizes and materials required for sand barriers.In this study,based on the original land grid division model for optimal resource utilization,we calculated the total side lengths of square and regular hexagonal sand barriers with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m in a desertified region of the Shapotou area on the southeastern edge of the Tengger Desert,China.Then,through literature review and social survey,we obtained the material cost and material utilization amount of sand barriers with different materials and sizes.Finally,we calculated the costs of square and regular hexagonal sand barriers comprised of wheat straw,corn stalk,Salix mongolica,poly lactic acid,magnesium cement,and high-density polyethylene,with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m.The results show that the material cost of regular hexagonal corn stalk sand barriers with the size of 3.0 m×3.0 m is the lowest,while the material cost of square magnesium cement sand barriers with the size of 1.0 m×1.0 m is the highest.When using the same material,the cost of regular hexagonal sand barriers is lower than that of square sand barriers with the same size.When using the same size,the cost of sand barriers with corn stalk material is lower than that of sand barriers with other materials.Based on the above analysis,we can conclude that the economic benefits of regular hexagonal sand barriers are greater than those of square sand barriers.This study provides a theoretical basis for accurately calculating the material cost of sand barriers,particularly for the estimated cost of mechanized sand barrier engineering projects.展开更多
Combined Economic and Emission Dispatch(CEED)task forms multi-objective optimization problems to be resolved to minimize emission and fuel costs.The disadvantage of the conventional method is its incapability to avoid...Combined Economic and Emission Dispatch(CEED)task forms multi-objective optimization problems to be resolved to minimize emission and fuel costs.The disadvantage of the conventional method is its incapability to avoid falling in local optimal,particularly when handling nonlinear and complex systems.Metaheuristics have recently received considerable attention due to their enhanced capacity to prevent local optimal solutions in addressing all the optimization problems as a black box.Therefore,this paper focuses on the design of an improved sand cat optimization algorithm based CEED(ISCOA-CEED)technique.The ISCOA-CEED technique majorly concen-trates on reducing fuel costs and the emission of generation units.Moreover,the presented ISCOA-CEED technique transforms the equality constraints of the CEED issue into inequality constraints.Besides,the improved sand cat optimization algorithm(ISCOA)is derived from the integration of tra-ditional SCOA with the Levy Flight(LF)concept.At last,the ISCOA-CEED technique is applied to solve a series of 6 and 11 generators in the CEED issue.The experimental validation of the ISCOA-CEED technique ensured the enhanced performance of the presented ISCOA-CEED technique over other recent approaches.展开更多
Drinking water is supplied through a centralized water supply system and may not be accessed by communities in rural areas of Malaysia.This study investigated the performance of a low-cost, self-prepared combined acti...Drinking water is supplied through a centralized water supply system and may not be accessed by communities in rural areas of Malaysia.This study investigated the performance of a low-cost, self-prepared combined activated carbon and sand filtration(CACSF) system for roofharvested rainwater and lake water for potable use. Activated carbon was self-prepared using locally sourced coconut shell and was activated using commonly available salt rather than a high-tech procedure that requires a chemical reagent. The filtration chamber was comprised of local,readily available sand. The experiments were conducted with varying antecedent dry intervals(ADIs) of up to 15 d and lake water with varying initial chemical oxygen demand(COD) concentration. The CACSF system managed to produce effluents complying with the drinking water standards for the parameters p H, dissolved oxygen(DO), biochemical oxygen demand(BOD5), COD, total suspended solids(TSS), and ammonia nitrogen(NH_3-N). The CACSF system successfully decreased the population of Escherichia coli(E. coli) in the influents to less than 30 CFU/m L. Samples with a higher population of E. coli(that is, greater than 30 CFU/m L) did not show 100% removal. The system also showed high potential as an alternative for treated drinking water for roof-harvested rainwater and class II lake water.展开更多
Water has always been an important and life-sustaining drink to humans and is essential to the survival of all known organisms. Over large parts of the world, humans have inadequate access to drinking water and use wa...Water has always been an important and life-sustaining drink to humans and is essential to the survival of all known organisms. Over large parts of the world, humans have inadequate access to drinking water and use water contaminated with disease vectors, pathogens or unacceptable levels of toxins or suspended solids. Drinking such water or using it in food preparation leads to widespread, acute and chronic illnesses and is a major cause of death and misery in many countries. The UN estimates that over 2.0 billion people have limited access to safe water and nearly 800 million people lack even the most basic supply of clean water. The main issue is the affordability of water purifying systems. Many people rely on boiling water or bottled water, which can be expensive. Therefore, technologies that are cost effective, sustainable, ease of operation/maintenance and the treatment processes with locally available materials are required. In this article, some unique low-cost sustainable technologies available/or in-use, i.e. natural filtration, riverbank filtration, biosand filtration, membrane filtration, solar water disinfection technique, biologically degradable materials such as moringa powder, scallop powder treatment, and biosand pitcher treatments have been discussed.展开更多
基金supported by the Research Program of Technology and Demonstration of Desert Margin Expansion Zone Stabilization for Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences(XDA23060201)。
文摘Sand barriers are the most widely used mechanical implements for wind-blown sand control and desertification prevention.However,there is no standard quantitative cost analysis of the sizes and materials required for sand barriers.In this study,based on the original land grid division model for optimal resource utilization,we calculated the total side lengths of square and regular hexagonal sand barriers with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m in a desertified region of the Shapotou area on the southeastern edge of the Tengger Desert,China.Then,through literature review and social survey,we obtained the material cost and material utilization amount of sand barriers with different materials and sizes.Finally,we calculated the costs of square and regular hexagonal sand barriers comprised of wheat straw,corn stalk,Salix mongolica,poly lactic acid,magnesium cement,and high-density polyethylene,with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m.The results show that the material cost of regular hexagonal corn stalk sand barriers with the size of 3.0 m×3.0 m is the lowest,while the material cost of square magnesium cement sand barriers with the size of 1.0 m×1.0 m is the highest.When using the same material,the cost of regular hexagonal sand barriers is lower than that of square sand barriers with the same size.When using the same size,the cost of sand barriers with corn stalk material is lower than that of sand barriers with other materials.Based on the above analysis,we can conclude that the economic benefits of regular hexagonal sand barriers are greater than those of square sand barriers.This study provides a theoretical basis for accurately calculating the material cost of sand barriers,particularly for the estimated cost of mechanized sand barrier engineering projects.
基金supported via funding from Prince Sattam bin Abdulaziz University project number(PSAU/2023/R/1444)The authors would like to thank the Deanship of Scientific Research at Umm Al-Qura University for supporting this work by Grant Code:22UQU4340237DSR65.
文摘Combined Economic and Emission Dispatch(CEED)task forms multi-objective optimization problems to be resolved to minimize emission and fuel costs.The disadvantage of the conventional method is its incapability to avoid falling in local optimal,particularly when handling nonlinear and complex systems.Metaheuristics have recently received considerable attention due to their enhanced capacity to prevent local optimal solutions in addressing all the optimization problems as a black box.Therefore,this paper focuses on the design of an improved sand cat optimization algorithm based CEED(ISCOA-CEED)technique.The ISCOA-CEED technique majorly concen-trates on reducing fuel costs and the emission of generation units.Moreover,the presented ISCOA-CEED technique transforms the equality constraints of the CEED issue into inequality constraints.Besides,the improved sand cat optimization algorithm(ISCOA)is derived from the integration of tra-ditional SCOA with the Levy Flight(LF)concept.At last,the ISCOA-CEED technique is applied to solve a series of 6 and 11 generators in the CEED issue.The experimental validation of the ISCOA-CEED technique ensured the enhanced performance of the presented ISCOA-CEED technique over other recent approaches.
基金supported by the Universiti Kebangsaan Malaysia Grant(Grant No.GUP-2014-077)
文摘Drinking water is supplied through a centralized water supply system and may not be accessed by communities in rural areas of Malaysia.This study investigated the performance of a low-cost, self-prepared combined activated carbon and sand filtration(CACSF) system for roofharvested rainwater and lake water for potable use. Activated carbon was self-prepared using locally sourced coconut shell and was activated using commonly available salt rather than a high-tech procedure that requires a chemical reagent. The filtration chamber was comprised of local,readily available sand. The experiments were conducted with varying antecedent dry intervals(ADIs) of up to 15 d and lake water with varying initial chemical oxygen demand(COD) concentration. The CACSF system managed to produce effluents complying with the drinking water standards for the parameters p H, dissolved oxygen(DO), biochemical oxygen demand(BOD5), COD, total suspended solids(TSS), and ammonia nitrogen(NH_3-N). The CACSF system successfully decreased the population of Escherichia coli(E. coli) in the influents to less than 30 CFU/m L. Samples with a higher population of E. coli(that is, greater than 30 CFU/m L) did not show 100% removal. The system also showed high potential as an alternative for treated drinking water for roof-harvested rainwater and class II lake water.
文摘Water has always been an important and life-sustaining drink to humans and is essential to the survival of all known organisms. Over large parts of the world, humans have inadequate access to drinking water and use water contaminated with disease vectors, pathogens or unacceptable levels of toxins or suspended solids. Drinking such water or using it in food preparation leads to widespread, acute and chronic illnesses and is a major cause of death and misery in many countries. The UN estimates that over 2.0 billion people have limited access to safe water and nearly 800 million people lack even the most basic supply of clean water. The main issue is the affordability of water purifying systems. Many people rely on boiling water or bottled water, which can be expensive. Therefore, technologies that are cost effective, sustainable, ease of operation/maintenance and the treatment processes with locally available materials are required. In this article, some unique low-cost sustainable technologies available/or in-use, i.e. natural filtration, riverbank filtration, biosand filtration, membrane filtration, solar water disinfection technique, biologically degradable materials such as moringa powder, scallop powder treatment, and biosand pitcher treatments have been discussed.