Accelerating Cooperative Planning for Automated Vehicles with Learned Heuristics and Monte Carlo Tree Search

Efficient driving in urban traffic scenarios requires foresight. The observation of other traffic participants and the inference of their possible next actions depending on the own action is considered cooperative prediction and planning. Humans are well equipped with the capability to predict the actions of multiple interacting traffic participants and plan accordingly, without the need to directly communicate with others. Prior work has shown that it is possible to achieve effective cooperative planning without the need for explicit communication. However, the search space for cooperative plans is so large that most of the computational budget is spent on exploring the search space in unpromising regions that are far away from the solution. To accelerate the planning process, we combined learned heuristics with a cooperative planning method to guide the search towards regions with promising actions, yielding better solutions at lower computational costs

Stochastic Hydrodynamic Synchronization in Rotating Energy Landscapes

Hydrodynamic synchronization provides a general mechanism for the spontaneous emergence of coherent beating states in independently driven mesoscopic oscillators. A complete physical picture of those phenomena is of definite importance to the understanding of biological cooperative motions of cilia and flagella. Moreover, it can potentially suggest novel routes to exploit synchronization in technological applications of soft matter. We demonstrate that driving colloidal particles in rotating energy landscapes results in a strong tendency towards synchronization, favouring states where all beads rotate in phase. The resulting dynamics can be described in terms of activated jumps with transition rates that are strongly affected by hydrodynamics leading to an increased probability and lifetime of the synchronous states. Using holographic optical tweezers we quantitatively verify our predictions in a variety of spatial configurations of rotors.Comment: Copyright (2013) by the American Physical Societ

Towards GMO-free landscapes? Identifying driving factors for the establishment of cooperative GMO-free zones in Germany

Since the end of the quasi-moratorium on genetically modified organisms (GMO) in the European Union in 2004, the establishment of GMO-free zones has become an EU wide phenomenon. In contrast to other European countries, Germany follows the concept of cooperative GMO-free zones where neighbouring farmers contractually refrain from GMO cultivation. In this article, we address the question which underlying factors could account for the establishment of cooperative GMO-free zones in Germany. Drawing on the existing literature on spatial agglomeration of different farming systems and the establishment of GMO-free zones, we provide the first systematic study on driving factors for the regional formation of GMO-free zones in Germany. The empirical analysis is based on a unique data set at the federal states level for the years 2004 to 2007. We show that infestation rates with the European Corn Borer, imminent Bt maize cultivation in the near vicinity and the number of arriving tourists mainly account for the establishment of cooperative GMO-free zones. This finding is consistent with the view that it is more the overall rejection of agro-biotechnology by broad strata of the population, including stakeholders in tourism and environmental protection, than economic benefits at the farm level which make German regions establish GMO-free zones.Genetically modified organisms (GMO), GMO-free zone, econometric analysis, Germany, Agribusiness,

Introduction - Towards Inter-organisational Systems in Peace Processes?

(...) Three fundamental issues will help us to make sense of the nature of cooperation during peace processes: the emergence of cooperation, the dynamics and relationships driving cooperation, and the institutionalisation of cooperative behaviour. As part of the presentation of our general theoretical framework, we will reflect on the existing literature as well as explain our own posture towards each of these analytical items. We will then end with a short summary of each contribution. (...

Granular transport in a horizontally vibrated sawtooth channel

We present a new mode of transport of spherical particles in a horizontally vibrated channel with sawtooth shaped side walls. The underlying driving mechanism is based on an interplay of directional energy injection transformed by the sidewall collisions and density dependent interparticle collisions. Experiments and matching numerics show that the average particle velocity reaches a maximum at 60% of the maximal filling density. Introducing a spatial phase shift between the channel boundaries increases the transport velocity by an order of magnitude.Comment: 5 pages, 8 figure

Driving safety: enhancing communication between clients, constructors and designers

This paper, which stems from qualitative research undertaken by the CRC for Construction Innovation in the context of the development of a Guide to Best Practice for Safer Construction in the Australian construction industry, investigates the communication relationship between the client, designer and constructor, and identifies the conditions under which effective communication takes place. Previous research has made little headway with respect to putting into practice strategies that have the potential to improve communication between the client, designer and constructor. This paper seeks to address this ongoing problem. From analysis of client, designer and constructor interviews that form part of industry-selected case studies reflecting excellence in OHS, best-practice tools that have the potential to enhance multi-party communication between the client, designer and constructor are presented. This research also informs the development of workable implementation strategies

Conditions and possible mechanism of condensation of e-h pairs in bulk GaAs at room temperature

A mechanism of the condensation of e-h pairs in bulk GaAs at room temperature, which has been observed earlier, is proposed. The point is that the photon assisted pairing happens in a system of electrons and holes that occupy energy levels at the very bottoms of the bands. Due to a very high e-h density, the destruction of the pairs and loss of coherency does not occur because almost all energy levels inside a 30-60 meV band from the bottom of the conduction band prove to be occupied. As a result, a coherent ensemble of composite bosons (paired electrons and holes) with the minimum possible energy appears. The lifetime of this strongly non-equilibrium coherent e-h BCS-like state is as short as a few hundred of femtosecondsComment: 10 pages, 8 figure

Safely Optimizing Highway Traffic with Robust Model Predictive Control-based Cooperative Adaptive Cruise Control

Road traffic crashes have been the leading cause of death among young people. Most of these accidents occur when the driver becomes distracted due to fatigue or external factors. Vehicle platooning systems such as Cooperative Adaptive Cruise Control (CACC) are one of the results of the effort devoted to the development of technologies for decreasing the number of road crashes and fatalities. Previous studies have suggested such systems improve up to 273\% highway traffic throughput and fuel consumption in more than 15\% if the clearance between vehicles in this class of roads can be reduced to 2 meters. This paper proposes an approach that guarantees a minimum safety distance between vehicles taking into account the overall system delays and braking capacity of each vehicle. A $l\infty$-norm Robust Model Predictive Controller (RMPC) is developed to guarantee the minimum safety distance is not violated due to uncertainties on the lead vehicle behavior. A formulation for a lower bound clearance of vehicles inside a platoon is also proposed. Simulation results show the performance of the proposed approach compared to a nominal controller when the system is subject to both modeled and unmodeled disturbances.Comment: Submitted to Transactions on Intelligent Transportation System