Supporting decisions on conflicting land-uses: An integrated ecological-economic approach

An integrated ecological-economic decision-making approach is developed to help local stakeholders decide on land use in rural areas where the conflict between natural resource protection and economic development is pressing. It consists of four methodological steps. In the first step the political options and alternatives for action regarding changes in the land-use pattern are specified in order to derive politically relevant land-use strategies (scenarios). In the second step economic, ecological and social indicators are derived. The third step includes economic modelling (economic input-output model), environmental modelling (modelling of landscape water balance) and the qualitative and quantitative estimation of ecological and environmental effects. These efforts result in the production of a multi-indicator matrix. Finally, the fourth step deals with a combined monetary and multi-criteria evaluation resulting in a ranking of the land-use strategies. The discussion of the decision-making approach concentrates on the necessity of preliminary decisions and the possibility and necessity of stakeholders participation in the decisionmaking process. --evaluation,decision-making,multi-criteria analysis,land-use management,scenarios,benefit-cost analysis

Balancing experiments on a torque-controlled humanoid with hierarchical inverse dynamics

Recently several hierarchical inverse dynamics controllers based on cascades of quadratic programs have been proposed for application on torque controlled robots. They have important theoretical benefits but have never been implemented on a torque controlled robot where model inaccuracies and real-time computation requirements can be problematic. In this contribution we present an experimental evaluation of these algorithms in the context of balance control for a humanoid robot. The presented experiments demonstrate the applicability of the approach under real robot conditions (i.e. model uncertainty, estimation errors, etc). We propose a simplification of the optimization problem that allows us to decrease computation time enough to implement it in a fast torque control loop. We implement a momentum-based balance controller which shows robust performance in face of unknown disturbances, even when the robot is standing on only one foot. In a second experiment, a tracking task is evaluated to demonstrate the performance of the controller with more complicated hierarchies. Our results show that hierarchical inverse dynamics controllers can be used for feedback control of humanoid robots and that momentum-based balance control can be efficiently implemented on a real robot.Comment: appears in IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 201

Momentum Control with Hierarchical Inverse Dynamics on a Torque-Controlled Humanoid

Hierarchical inverse dynamics based on cascades of quadratic programs have been proposed for the control of legged robots. They have important benefits but to the best of our knowledge have never been implemented on a torque controlled humanoid where model inaccuracies, sensor noise and real-time computation requirements can be problematic. Using a reformulation of existing algorithms, we propose a simplification of the problem that allows to achieve real-time control. Momentum-based control is integrated in the task hierarchy and a LQR design approach is used to compute the desired associated closed-loop behavior and improve performance. Extensive experiments on various balancing and tracking tasks show very robust performance in the face of unknown disturbances, even when the humanoid is standing on one foot. Our results demonstrate that hierarchical inverse dynamics together with momentum control can be efficiently used for feedback control under real robot conditions.Comment: 21 pages, 11 figures, 4 tables in Autonomous Robots (2015

Gewinnabschöpfung unter der Flagge der positiven Generalprävention

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.Peer Reviewe

Limites del derecho penal para controlar los riesgos sociales (Una perspectiva crítica ante el derecho penal de peligro)

Limites del derecho penal para controlar los riesgos sociales (Una perspectiva crítica ante el derecho penal de peligro

Differential effects of habitat isolation and landscape composition on wasps, bees, and their enemies

Habitat loss and fragmentation are major threats to biodiversity and ecosystem functioning. Effects of these usually intercorrelated processes on biodiversity have rarely been separated at a landscape scale. We studied the independent effects of amount of woody habitat in the landscape and three levels of isolation from the next woody habitat (patch isolation) on trap nesting bees, wasps, and their enemies at 30 farmland sites in the Swiss plateau. Species richness of wasps was negatively affected by patch isolation and positively affected by the amount of woody habitat in the landscape. In contrast, species richness of bees was neither influenced by patch isolation nor by landscape composition. Isolation from woody habitats reduced species richness and abundance of natural enemies more strongly than of their hosts, so that parasitism rate was lowered by half in isolated sites compared to forest edges. Thus, population regulation of the hosts may be weakened by habitat fragmentation. We conclude that habitat amount at the landscape scale and local patch connectivity are simultaneously important for biodiversity conservatio

Spiders associated with the meadow and tree canopies of orchards respond differently to habitat fragmentation

The response of animal communities to habitat quality and fragmentation may vary depending on microhabitat associations of species. For example, sensitivity of species to woody habitat fragmentation should increase with their degree of association with woody plants. We investigated effects of local and landscape factors on spider communities in different microhabitats within Swiss apple orchards. We expected a stronger negative effect of woody habitat fragmentation on spiders inhabiting tree canopies compared to spiders living in the meadow. The 30 orchards that we sampled varied in woody habitat amount and isolation at landscape and patch scales. Local factors included management intensity and plant diversity. Spiders associated with meadow were affected by plant diversity, but not by fragmentation. In contrast, spiders associated with canopies responded to isolation from other woody habitats. Surprisingly, we found both positive and negative effects of habitat isolation on local abundance. This indicates that differences in dispersal and/or biotic interactions shape the specific response to habitat isolation. The relative importance of local and landscape factors was in accordance with the microhabitat of the spiders. Thus, considering microhabitat associations can be important for identifying processes that would be overlooked if sampling were pooled for the whole habita