The application field for Unmanned Aerial Vehicle (UAV) technology and its adoption rate have been increasingsteadily in the past years. Decreasing cost of commercial drones has enabled their use at a scale broader th...The application field for Unmanned Aerial Vehicle (UAV) technology and its adoption rate have been increasingsteadily in the past years. Decreasing cost of commercial drones has enabled their use at a scale broader thanever before. However, increasing the complexity of UAVs and decreasing the cost, both contribute to a lack ofimplemented securitymeasures and raise new security and safety concerns. For instance, the issue of implausible ortampered UAV sensor measurements is barely addressed in the current research literature and thus, requires moreattention from the research community. The goal of this survey is to extensively review state-of-the-art literatureregarding common sensor- and communication-based vulnerabilities, existing threats, and active or passive cyberattacksagainst UAVs, as well as shed light on the research gaps in the literature. In this work, we describe theUnmanned Aerial System (UAS) architecture to point out the origination sources for security and safety issues.Weevaluate the coverage and completeness of each related research work in a comprehensive comparison table as wellas classify the threats, vulnerabilities and cyber-attacks into sensor-based and communication-based categories.Additionally, for each individual cyber-attack, we describe existing countermeasures or detectionmechanisms andprovide a list of requirements to ensureUAV’s security and safety.We also address the problem of implausible sensormeasurements and introduce the idea of a plausibility check for sensor data. By doing so, we discover additionalmeasures to improve security and safety and report on a research niche that is not well represented in the currentresearch literature.展开更多
Among challenges implicit in the transition to the post-fossil fuel energetic model,the finite amount of resources available for the technological implementation of CO_(2) revalorizing processes arises as a central is...Among challenges implicit in the transition to the post-fossil fuel energetic model,the finite amount of resources available for the technological implementation of CO_(2) revalorizing processes arises as a central issue.The development of fully renewable catalytic systems with easier metal recovery strategies would promote the viability and sustainability of synthetic natural gas production circular routes.Taking Ni and NiFe catalysts supported over g-Al_(2)O_(3) oxide as reference materials,this work evaluates the potentiality of Ni and NiFe supported biochar catalysts for CO_(2) methanation.The development of competitive biochar catalysts was found dependent on the creation of basic sites on the catalyst surface.Displaying lower Turn Over Frequencies than Ni/Al catalyst,the absence of basic sites achieved over Ni/C catalyst was related to the depleted catalyst performances.For NiFe catalysts,analogous Ni_(5)Fe_(1) alloys were constituted over both alumina and biochar supports.The highest specific activity of the catalyst series,exhibited by the NiFe/C catalyst,was related to the development of surface basic sites along with weaker NiFe-C interactions,which resulted in increased Ni0:NiO surface populations under reaction conditions.In summary,the present work establishes biochar supports as a competitive material to consider within the future low-carbon energetic panorama.展开更多
In times of highest necessities for United Nations Sustainable Development Goals(SDGs)and acknowledging planetary boundaries,the need for understanding general global goals and regional to local strategic governing st...In times of highest necessities for United Nations Sustainable Development Goals(SDGs)and acknowledging planetary boundaries,the need for understanding general global goals and regional to local strategic governing structures has to be supported while combining assessment,monitoring,governance approaches,together with landscape planning,land use based approaches,land system and sustainability science.The initial research embeds an incrementally worked out theoretical framework followed by applied research parts.The case studies and field data in the German Lusatia Region and inner part Spree Forest Region inhabit intrinsic drivers of finding ways over bridging deficiencies of theoretical and applied adjusted objectives and in this small excerpt mainly about the scale and planning level,instrumental flexibility deficiencies while transmitting global transformation needs to the regional,local planning level and backward(counter-current principle).Innovative instrumental assessment structures were created with a new approach of spatially determining SDGs for accelerated Climate Smart Planning(CSP)and Integrated Drought and Water Management(IDWM).This research supports processes around acceleration and assessment of climate change-,crises-related and sustainable development options while enhancing interdisciplinary sustainability science for gaining more regional land resilience.展开更多
Tropical mountain ranges shape the structure of tree communities and promote highly diverse natural habitats.The“Bosque Protector Chong on-Colonche”(BPCC),an 86,000-ha mountain formation situated on the coast of Ecu...Tropical mountain ranges shape the structure of tree communities and promote highly diverse natural habitats.The“Bosque Protector Chong on-Colonche”(BPCC),an 86,000-ha mountain formation situated on the coast of Ecuador,is biogeographically important for the region by connecting floristic elements of the wet Choco and the dry Tumbesian forests.Our understanding of the factors that model tree and palm diversity and distribution in this mountain range are limited.We measured and identified all trees and palms(DBH≥10 cm)in 289 plots of0.2 ha,distributed throughout BPCC.We used generalized linear models to explain the relationship between forest diversity and structure and climatic variables(temperature,rain,aridity),and altitude.We then used cluster and non-metric multidimensional scale(NMDS)analyses to search for distinct forest communities within the BPCC.Variance partition(varpart)was used to determine which predictor variables best explained these distinct forest communities.A species indicator analysis identified the species most likely to define these distinct forest communities.Finally,we carried out a niche modeling approach to identify the potential distribution of these forest communities within BPCC.In total,we identified 220 tree and palm species in our survey.The average number of species per plot was 17.8±5.8,ranging from 3 to 40 species.Classification methods sorted the 289study plots into six different forest communities,three communities in the dry forest and three in the semi-humid Garúa forest.Precipitation and temperature,but not altitude or aridity,explained floristic composition.These results emphasize the high but little cataloged diversity in the lowland mountain rainforests of coastal Ecuador.展开更多
基金the FederalMinistry of Education and Research of Germany under Grant Numbers 16ES1131 and 16ES1128K.
文摘The application field for Unmanned Aerial Vehicle (UAV) technology and its adoption rate have been increasingsteadily in the past years. Decreasing cost of commercial drones has enabled their use at a scale broader thanever before. However, increasing the complexity of UAVs and decreasing the cost, both contribute to a lack ofimplemented securitymeasures and raise new security and safety concerns. For instance, the issue of implausible ortampered UAV sensor measurements is barely addressed in the current research literature and thus, requires moreattention from the research community. The goal of this survey is to extensively review state-of-the-art literatureregarding common sensor- and communication-based vulnerabilities, existing threats, and active or passive cyberattacksagainst UAVs, as well as shed light on the research gaps in the literature. In this work, we describe theUnmanned Aerial System (UAS) architecture to point out the origination sources for security and safety issues.Weevaluate the coverage and completeness of each related research work in a comprehensive comparison table as wellas classify the threats, vulnerabilities and cyber-attacks into sensor-based and communication-based categories.Additionally, for each individual cyber-attack, we describe existing countermeasures or detectionmechanisms andprovide a list of requirements to ensureUAV’s security and safety.We also address the problem of implausible sensormeasurements and introduce the idea of a plausibility check for sensor data. By doing so, we discover additionalmeasures to improve security and safety and report on a research niche that is not well represented in the currentresearch literature.
文摘Among challenges implicit in the transition to the post-fossil fuel energetic model,the finite amount of resources available for the technological implementation of CO_(2) revalorizing processes arises as a central issue.The development of fully renewable catalytic systems with easier metal recovery strategies would promote the viability and sustainability of synthetic natural gas production circular routes.Taking Ni and NiFe catalysts supported over g-Al_(2)O_(3) oxide as reference materials,this work evaluates the potentiality of Ni and NiFe supported biochar catalysts for CO_(2) methanation.The development of competitive biochar catalysts was found dependent on the creation of basic sites on the catalyst surface.Displaying lower Turn Over Frequencies than Ni/Al catalyst,the absence of basic sites achieved over Ni/C catalyst was related to the depleted catalyst performances.For NiFe catalysts,analogous Ni_(5)Fe_(1) alloys were constituted over both alumina and biochar supports.The highest specific activity of the catalyst series,exhibited by the NiFe/C catalyst,was related to the development of surface basic sites along with weaker NiFe-C interactions,which resulted in increased Ni0:NiO surface populations under reaction conditions.In summary,the present work establishes biochar supports as a competitive material to consider within the future low-carbon energetic panorama.
文摘In times of highest necessities for United Nations Sustainable Development Goals(SDGs)and acknowledging planetary boundaries,the need for understanding general global goals and regional to local strategic governing structures has to be supported while combining assessment,monitoring,governance approaches,together with landscape planning,land use based approaches,land system and sustainability science.The initial research embeds an incrementally worked out theoretical framework followed by applied research parts.The case studies and field data in the German Lusatia Region and inner part Spree Forest Region inhabit intrinsic drivers of finding ways over bridging deficiencies of theoretical and applied adjusted objectives and in this small excerpt mainly about the scale and planning level,instrumental flexibility deficiencies while transmitting global transformation needs to the regional,local planning level and backward(counter-current principle).Innovative instrumental assessment structures were created with a new approach of spatially determining SDGs for accelerated Climate Smart Planning(CSP)and Integrated Drought and Water Management(IDWM).This research supports processes around acceleration and assessment of climate change-,crises-related and sustainable development options while enhancing interdisciplinary sustainability science for gaining more regional land resilience.
文摘Tropical mountain ranges shape the structure of tree communities and promote highly diverse natural habitats.The“Bosque Protector Chong on-Colonche”(BPCC),an 86,000-ha mountain formation situated on the coast of Ecuador,is biogeographically important for the region by connecting floristic elements of the wet Choco and the dry Tumbesian forests.Our understanding of the factors that model tree and palm diversity and distribution in this mountain range are limited.We measured and identified all trees and palms(DBH≥10 cm)in 289 plots of0.2 ha,distributed throughout BPCC.We used generalized linear models to explain the relationship between forest diversity and structure and climatic variables(temperature,rain,aridity),and altitude.We then used cluster and non-metric multidimensional scale(NMDS)analyses to search for distinct forest communities within the BPCC.Variance partition(varpart)was used to determine which predictor variables best explained these distinct forest communities.A species indicator analysis identified the species most likely to define these distinct forest communities.Finally,we carried out a niche modeling approach to identify the potential distribution of these forest communities within BPCC.In total,we identified 220 tree and palm species in our survey.The average number of species per plot was 17.8±5.8,ranging from 3 to 40 species.Classification methods sorted the 289study plots into six different forest communities,three communities in the dry forest and three in the semi-humid Garúa forest.Precipitation and temperature,but not altitude or aridity,explained floristic composition.These results emphasize the high but little cataloged diversity in the lowland mountain rainforests of coastal Ecuador.
