A potential energy framework for assessment of grid vulnerability was presented.In the framework,the branch potential energy function model was constructed.Two indexes,current vulnerability and forecasting vulnerabili...A potential energy framework for assessment of grid vulnerability was presented.In the framework,the branch potential energy function model was constructed.Two indexes,current vulnerability and forecasting vulnerability,were calculated.The current vulnerability was used to identify the current vulnerable area through calculating the distance between the current transmitted power and initial transmitted power;and the forecast vulnerability under variation of power injection was used to predict the vulnerable area of next step and verify the current vulnerable area.Numerical simulation was performed under variant operating conditions with IEEE-30 bus system,which shows that almost area of 90% overlaps between current vulnerable area and forecasting vulnerable area,the overlapped area is termed as inherent vulnerable area of grid.When considering N-1 contingency,the assessment results of this method proposed agree with those of optimal power flow.When considering N-2 contingency,optimal power flow fails to obtain correct results,while the method based on energy framework gives reliable results.展开更多
This article assesses the current state of disaster risk reduction(DRR) in the Greater Horn of Africa(GHA),and focuses on interventions and policies to mitigate hydrometeorological risks. The research analyzes, as mai...This article assesses the current state of disaster risk reduction(DRR) in the Greater Horn of Africa(GHA),and focuses on interventions and policies to mitigate hydrometeorological risks. The research analyzes, as main case study, the program 'Regional Climate Prediction and Risk Reduction in the Greater Horn of Africa'funded by the Office of U.S. Foreign Disaster Assistance(USAID OFDA) in the early 2000 that targeted risk preparedness.The research method combines a desk review of relevant documents and research papers with surveys and interviews directed to key proponents of DRR across the GHA. Results highlight current strengths and weaknesses in the way DRR is implemented in the GHA. Significant improvements in the climate-forecasting capabilities in the GHA since the 2000 s are acknowledged, but the practice of DRR remains technology driven and impacts on the ground are limited. The key findings highlight the significant communication gaps that exist between the producers of climate information and their end users, the communities at risk. The article urges the establishment of bridges that connect climate experts, policymakers, and representatives of the local communities, and for the implementation of a feedback loop from forecast users to their producers, in order to strengthen risk resilience across the GHA.展开更多
基金Project(51007006) supported by the National Natural Science Foundation of ChinaProject(20090185120023) supported by the Ph.D Programs Foundation for New Teacher of Ministry of Education of China
文摘A potential energy framework for assessment of grid vulnerability was presented.In the framework,the branch potential energy function model was constructed.Two indexes,current vulnerability and forecasting vulnerability,were calculated.The current vulnerability was used to identify the current vulnerable area through calculating the distance between the current transmitted power and initial transmitted power;and the forecast vulnerability under variation of power injection was used to predict the vulnerable area of next step and verify the current vulnerable area.Numerical simulation was performed under variant operating conditions with IEEE-30 bus system,which shows that almost area of 90% overlaps between current vulnerable area and forecasting vulnerable area,the overlapped area is termed as inherent vulnerable area of grid.When considering N-1 contingency,the assessment results of this method proposed agree with those of optimal power flow.When considering N-2 contingency,optimal power flow fails to obtain correct results,while the method based on energy framework gives reliable results.
基金support of the Office of US Foreign Disaster AssistanceBureau for Democracy+7 种基金Conflict and Humanitarian AssistanceUS Agency for International Developmentthe IGAD Climate Prediction and Applications Centre (ICPAC in Nairobi)NOAA’s National Weather Servicethe University of Nairobithe University of Coloradothe Kenya Meteorological Department (KMD)One Acre Fund NGO
文摘This article assesses the current state of disaster risk reduction(DRR) in the Greater Horn of Africa(GHA),and focuses on interventions and policies to mitigate hydrometeorological risks. The research analyzes, as main case study, the program 'Regional Climate Prediction and Risk Reduction in the Greater Horn of Africa'funded by the Office of U.S. Foreign Disaster Assistance(USAID OFDA) in the early 2000 that targeted risk preparedness.The research method combines a desk review of relevant documents and research papers with surveys and interviews directed to key proponents of DRR across the GHA. Results highlight current strengths and weaknesses in the way DRR is implemented in the GHA. Significant improvements in the climate-forecasting capabilities in the GHA since the 2000 s are acknowledged, but the practice of DRR remains technology driven and impacts on the ground are limited. The key findings highlight the significant communication gaps that exist between the producers of climate information and their end users, the communities at risk. The article urges the establishment of bridges that connect climate experts, policymakers, and representatives of the local communities, and for the implementation of a feedback loop from forecast users to their producers, in order to strengthen risk resilience across the GHA.
