The concept of community resilience in the contexts of climate change and disasters draws increasing attention and interest from practitioners and researchers in recent development discourse. This paper provides a cri...The concept of community resilience in the contexts of climate change and disasters draws increasing attention and interest from practitioners and researchers in recent development discourse. This paper provides a critical review of six selected frameworks of community resilience building operationalized in Bangladesh over the span of years. In other words, this study aims to contribute to the understanding of resilience through a systematic analysis of the dimensions and indicators of community resilience frameworks. The analysis shows that comprehensive and effective community resilience frameworks should incorporate the missing components linked to fundamental elements of good governance, economic growth, environmental sustainability, social transformation, and capacity development. The paper concludes by highlighting a few other areas of grave concern that need more appropriate attention, considering the severe threats posed by climate change and natural disasters in line with sustainable development goals. Finally, this study recommends further research regarding the effectiveness of these frameworks in different climatic and disaster contexts that can lead the concept into a new dimension of community resilience and sustainability.展开更多
In recent decades,intelligent transportation systems(ITS)have improved drivers’safety and have shared information(such as traffic congestion and accidents)in a very efficient way.However,the privacy of vehicles and t...In recent decades,intelligent transportation systems(ITS)have improved drivers’safety and have shared information(such as traffic congestion and accidents)in a very efficient way.However,the privacy of vehicles and the security of event information is a major concern.The problem of secure sharing of event information without compromising the trusted third party(TTP)and data storage is the main issue in ITS.Blockchain technologies can resolve this problem.A work has been published on blockchain-based protocol for secure sharing of events and authentication of vehicles.This protocol addresses the issue of the safe storing of event information.However,authentication of vehicles solely depends on the cloud server.As a result,their scheme utilizes the notion of partially decentralized architecture.This paper proposes a novel decentralized architecture for the vehicular ad-hoc network(VANET)without the cloud server.This work also presents a protocol for securing event information and vehicle authentication using the blockchain mechanism.In this protocol,the registered user accesses the event information securely from the interplanetary file system(IPFS).We incorporate the IPFS,along with blockchain,to store the information in a fully distributed manner.The proposed protocol is compared with the state-of-the-art.The comparison provides desirable security at a reasonable cost.The evaluation of the proposed smart contract in terms of cost(GAS)is also discussed.展开更多
Biochar has potentials for soil fertility improvement, climate change mitigation and environmental reclamation, and charred biomass can be deliberately incorporated into soil for long-term carbon stabilization and soi...Biochar has potentials for soil fertility improvement, climate change mitigation and environmental reclamation, and charred biomass can be deliberately incorporated into soil for long-term carbon stabilization and soil amendment. Many different methods have been used for biochar production ranging from laboratory to industrial scales. However, in countryside of developing countries, biomass is generally used for cooking but not charred. Biochar production techniques at farmer scale have remained poorly developed. We developed and tested biochar production kilns for farmers with a dimension of 50.8 cm × 38.1 cm (height × diameter), using three different setups for optimizing oxygen (02) limitation and syngas circulation: airtight with no syngas circulation (Model I), semi-airtight with external syngas circulation (Model II) and semi-airtight with internal syngas circulation (Model III). A comparative assessment of these biochar production kiln models was made considering biochar pyrolysis time, fuel to biomass ratio, biochar to feedstock ratio and thermogravimetric index (TGI). Among the models, the best quality biochar (TGI ---- 0.15) was obtained from Model I kiln taking the longest time for pyrolysis (12.5 h) and the highest amount of fuel wood (1.22 kg kg-1 biomass). Model III kiln produced comparatively good quality biochar (TGI = 0.11), but with less fuel wood requirement (0.33 kg kg-1 biomass) and shorter pyrolysis time (8.5 h). We also tested Model III kiln in a three times larger size under two situations (steel kiln and pit kiln). The biochar to feedstock ratio (0.38) and quality (TGI =0.14) increased slightly for the larger kilns. Quality of biochar was found to be mainly related to pyrolysis time. The costs for the biochar stove and pit kiln were US$ 65-77, while it was US$ 154 for the large size steel kiln. Model III kiln can potentially be used for both cooking and biochar production at farmer scale.展开更多
文摘The concept of community resilience in the contexts of climate change and disasters draws increasing attention and interest from practitioners and researchers in recent development discourse. This paper provides a critical review of six selected frameworks of community resilience building operationalized in Bangladesh over the span of years. In other words, this study aims to contribute to the understanding of resilience through a systematic analysis of the dimensions and indicators of community resilience frameworks. The analysis shows that comprehensive and effective community resilience frameworks should incorporate the missing components linked to fundamental elements of good governance, economic growth, environmental sustainability, social transformation, and capacity development. The paper concludes by highlighting a few other areas of grave concern that need more appropriate attention, considering the severe threats posed by climate change and natural disasters in line with sustainable development goals. Finally, this study recommends further research regarding the effectiveness of these frameworks in different climatic and disaster contexts that can lead the concept into a new dimension of community resilience and sustainability.
文摘In recent decades,intelligent transportation systems(ITS)have improved drivers’safety and have shared information(such as traffic congestion and accidents)in a very efficient way.However,the privacy of vehicles and the security of event information is a major concern.The problem of secure sharing of event information without compromising the trusted third party(TTP)and data storage is the main issue in ITS.Blockchain technologies can resolve this problem.A work has been published on blockchain-based protocol for secure sharing of events and authentication of vehicles.This protocol addresses the issue of the safe storing of event information.However,authentication of vehicles solely depends on the cloud server.As a result,their scheme utilizes the notion of partially decentralized architecture.This paper proposes a novel decentralized architecture for the vehicular ad-hoc network(VANET)without the cloud server.This work also presents a protocol for securing event information and vehicle authentication using the blockchain mechanism.In this protocol,the registered user accesses the event information securely from the interplanetary file system(IPFS).We incorporate the IPFS,along with blockchain,to store the information in a fully distributed manner.The proposed protocol is compared with the state-of-the-art.The comparison provides desirable security at a reasonable cost.The evaluation of the proposed smart contract in terms of cost(GAS)is also discussed.
基金supported by Patuakhali Science and Technology University (PSTU),Bangladesh
文摘Biochar has potentials for soil fertility improvement, climate change mitigation and environmental reclamation, and charred biomass can be deliberately incorporated into soil for long-term carbon stabilization and soil amendment. Many different methods have been used for biochar production ranging from laboratory to industrial scales. However, in countryside of developing countries, biomass is generally used for cooking but not charred. Biochar production techniques at farmer scale have remained poorly developed. We developed and tested biochar production kilns for farmers with a dimension of 50.8 cm × 38.1 cm (height × diameter), using three different setups for optimizing oxygen (02) limitation and syngas circulation: airtight with no syngas circulation (Model I), semi-airtight with external syngas circulation (Model II) and semi-airtight with internal syngas circulation (Model III). A comparative assessment of these biochar production kiln models was made considering biochar pyrolysis time, fuel to biomass ratio, biochar to feedstock ratio and thermogravimetric index (TGI). Among the models, the best quality biochar (TGI ---- 0.15) was obtained from Model I kiln taking the longest time for pyrolysis (12.5 h) and the highest amount of fuel wood (1.22 kg kg-1 biomass). Model III kiln produced comparatively good quality biochar (TGI = 0.11), but with less fuel wood requirement (0.33 kg kg-1 biomass) and shorter pyrolysis time (8.5 h). We also tested Model III kiln in a three times larger size under two situations (steel kiln and pit kiln). The biochar to feedstock ratio (0.38) and quality (TGI =0.14) increased slightly for the larger kilns. Quality of biochar was found to be mainly related to pyrolysis time. The costs for the biochar stove and pit kiln were US$ 65-77, while it was US$ 154 for the large size steel kiln. Model III kiln can potentially be used for both cooking and biochar production at farmer scale.