As the economy takes off in Austria, voters remain torn between economic optimism and anti-immigration politics

With under two weeks left until the Austrian legislative election on 15 October, the centre-right People's Party (ÖVP), led by Sebastian Kurz, currently leads the opinion polls. Michael Burri writes that the refugee-centred campaign of Kurz has resonated with the public, allowing the ÖVP to counter the economic message emphasised by incumbent Chancellor Christian Kern. And while an improving economy may weakened anti-refugee politics since the peak of the refugee crisis in 2015, refugees still provide a powerful means through which to discuss national community and national destiny

Sampling-based Motion Planning for Active Multirotor System Identification

This paper reports on an algorithm for planning trajectories that allow a multirotor micro aerial vehicle (MAV) to quickly identify a set of unknown parameters. In many problems like self calibration or model parameter identification some states are only observable under a specific motion. These motions are often hard to find, especially for inexperienced users. Therefore, we consider system model identification in an active setting, where the vehicle autonomously decides what actions to take in order to quickly identify the model. Our algorithm approximates the belief dynamics of the system around a candidate trajectory using an extended Kalman filter (EKF). It uses sampling-based motion planning to explore the space of possible beliefs and find a maximally informative trajectory within a user-defined budget. We validate our method in simulation and on a real system showing the feasibility and repeatability of the proposed approach. Our planner creates trajectories which reduce model parameter convergence time and uncertainty by a factor of four.Comment: Published at ICRA 2017. Video available at https://www.youtube.com/watch?v=xtqrWbgep5

Visual-inertial self-calibration on informative motion segments

Environmental conditions and external effects, such as shocks, have a significant impact on the calibration parameters of visual-inertial sensor systems. Thus long-term operation of these systems cannot fully rely on factory calibration. Since the observability of certain parameters is highly dependent on the motion of the device, using short data segments at device initialization may yield poor results. When such systems are additionally subject to energy constraints, it is also infeasible to use full-batch approaches on a big dataset and careful selection of the data is of high importance. In this paper, we present a novel approach for resource efficient self-calibration of visual-inertial sensor systems. This is achieved by casting the calibration as a segment-based optimization problem that can be run on a small subset of informative segments. Consequently, the computational burden is limited as only a predefined number of segments is used. We also propose an efficient information-theoretic selection to identify such informative motion segments. In evaluations on a challenging dataset, we show our approach to significantly outperform state-of-the-art in terms of computational burden while maintaining a comparable accuracy

Build Your Own Visual-Inertial Drone: A Cost-Effective and Open-Source Autonomous Drone

This paper describes an approach to building a cost-effective and research grade visual-inertial odometry aided vertical taking-off and landing (VTOL) platform. We utilize an off-the-shelf visual-inertial sensor, an onboard computer, and a quadrotor platform that are factory-calibrated and mass-produced, thereby sharing similar hardware and sensor specifications (e.g., mass, dimensions, intrinsic and extrinsic of camera-IMU systems, and signal-to-noise ratio). We then perform a system calibration and identification enabling the use of our visual-inertial odometry, multi-sensor fusion, and model predictive control frameworks with the off-the-shelf products. This implies that we can partially avoid tedious parameter tuning procedures for building a full system. The complete system is extensively evaluated both indoors using a motion capture system and outdoors using a laser tracker while performing hover and step responses, and trajectory following tasks in the presence of external wind disturbances. We achieve root-mean-square (RMS) pose errors between a reference and actual trajectories of 0.036m, while performing hover. We also conduct relatively long distance flight (~180m) experiments on a farm site and achieve 0.82% drift error of the total distance flight. This paper conveys the insights we acquired about the platform and sensor module and returns to the community as open-source code with tutorial documentation.Comment: 21 pages, 10 figures, accepted to IEEE Robotics & Automation Magazin

A Primer on the Differential Calculus of 3D Orientations

The proper handling of 3D orientations is a central element in many optimization problems in engineering. Unfortunately many researchers and engineers struggle with the formulation of such problems and often fall back to suboptimal solutions. The existence of many different conventions further complicates this issue, especially when interfacing multiple differing implementations. This document discusses an alternative approach which makes use of a more abstract notion of 3D orientations. The relative orientation between two coordinate systems is primarily identified by the coordinate mapping it induces. This is combined with the standard exponential map in order to introduce representation-independent and minimal differentials, which are very convenient in optimization based methods

Serum protein electrophoresis : an underused but very useful test

Serum protein electrophoresis is used in clinical practice to identify patients with multiple myeloma and other serum protein disorders. It is an inexpensive and easy-to-perform screening procedure. Electrophoresis separates serum proteins based on their physical properties and identifies morphologic patterns in response to acute and chronic inflammation, various malignancies, liver or renal failure, and hereditary protein disorders. For gastroenterologists, the use of serum protein electrophoresis may be helpful in the diagnosis of both common diseases with unusual presentations and rare disorders with typical presentations. Therefore, it represents an ideal screening tool

Cichlids do not adjust reproductive skew to the availability of independent breeding options

Helpers in cooperatively breeding species forego all or part of their reproduction when remaining at home and assisting breeders to raise offspring. Different models of reproductive skew generate alternative predictions about the share of reproduction unrelated subordinates will get depending on the degree of ecological constraints. Concession models predict a larger share when independent breeding options are good, whereas restraint and tug-of-war models predict no effects on reproductive skew. We tested these predictions by determining the share of reproduction by unrelated male and female helpers in the Lake Tanganyika cichlid Neolamprologus pulcher depending on experimentally manipulated possibilities for helper dispersal and independent breeding and depending on helper size and sex. We created 32 breeding groups in the laboratory, consisting of two breeders and two helpers each, where only the helpers had access to a nearby dispersal compartment with (treatment) or without (control) breeding substrate, using a repeated measures design. We determined the paternity and maternity of 1185 offspring from 47 broods using five to nine DNA microsatellite loci and found that: (1) helpers participated in reproduction equally across the treatments, (2) large male helpers were significantly more likely to reproduce than small helpers, and (3) male helpers engaged in significantly more reproduction than female helpers. Interestingly, in four broods, extragroup helper males had fertilized part of the brood. No helper evictions from the group after helper reproduction were observed. Our results suggest that tug-of-war models based on competition over reproduction within groups describe best the reproductive skew observed in our study system. Female breeders produced larger clutches in the treatment compared to the control situation when the large helpers were males. This suggests that male breeder-male helper reproductive conflicts may be alleviated by females producing larger clutches with helpers aroun

Student Teachers’ Cognition about L2 Pronunciation Instruction: A Case Study

In view of the minimal attention pronunciation teacher preparation has received in second language (L2) teacher education, this study examined the cognition (i.e. beliefs, thoughts, attitudes and knowledge) development of 15 student teachers during a postgraduate subject on pronunciation pedagogy offered at an Australian tertiary institution. Findings revealed that, as a result of taking the subject, student teachers’ cognition shifted from teaching individual sounds (i.e. segmentals) to favouring a more balanced approach to pronunciation instruction. That is, teaching the melody of the English language (i.e. suprasegmentals) was seen as important as teaching segmentals. Non-native speakers’ self-perceived pronunciation improvement, an increase in their awareness of their spoken English, and native/non-native collaboration played critical roles in facilitating participants’ cognition growth. The findings also showed that cognition development is a complex process. The paper concludes with recommendations for preparing L2 teachers to teach English pronunciation in their classroom contexts

Conducting Qualitative Longitudinal Research on Learning to Teach English Pronunciation: Challenges, Pitfalls…Coffee, and Bubbles!

Inquiries into the impact of second language teacher education on the development of teachers\u27 practices, beliefs, and knowledge have increased substantially in the last few years. However, most studies tend to investigate the process of second language teacher learning over a relatively short period of time, and only limited literature addresses methodological considerations in longitudinal research, making the design of this type of study potentially challenging for researchers. The aim of this paper is to first describe an ongoing project which explores the process of teachers learning to teach English pronunciation over a period of six years. Following an overview of the study design, five major challenges that I have faced while conducting the research project are discussed: (1) design issues; (2) access to teacher-participants; (3) time-related issues; (4) data management; and (5) personal involvement. Included in the discussion are methodological insights I have gained while carrying out the research and several navigational strategies I have used to overcome the aforementioned challenges. The purpose of providing this personal account is to shed light on my own experiences with navigating methodological challenges as a means of empowering researchers in designing and carrying out longitudinal research