Autonomous navigation of unmanned aerial vehicles (UAVs) in GPS‐denied environments is a challenging problem, especially for small‐scale UAVs characterized by a small payload and limited battery ...autonomy. A possible solution to the aforementioned problem is vision‐based simultaneous localization and mapping (SLAM), since cameras, due to their dimensions, low weight, availability, and large information bandwidth, circumvent all the constraints of UAVs. In this paper, we propose a stereo vision SLAM yielding very accurate localization and a dense map of the environment developed with the aim to compete in the European Robotics Challenges (EuRoC) targeting airborne inspection of industrial facilities with small‐scale UAVs. The proposed approach consists of a novel stereo odometry algorithm relying on feature tracking (SOFT), which currently ranks first among all stereo methods on the KITTI dataset. Relying on SOFT for pose estimation, we build a feature‐based pose graph SLAM solution, which we dub SOFT‐SLAM. SOFT‐SLAM has a completely separate odometry and mapping threads supporting large loop‐closing and global consistency. It also achieves a constant‐time execution rate of 20 Hz with deterministic results using only two threads of an onboard computer used in the challenge. The UAV running our SLAM algorithm obtained the highest localization score in the EuRoC Challenge 3, Stage IIa–Benchmarking, Task 2. Furthermore, we also present an exhaustive evaluation of SOFT‐SLAM on two popular public datasets, and we compare it to other state‐of‐the‐art approaches, namely ORB‐SLAM2 and LSD‐SLAM. The results show that SOFT‐SLAM obtains better localization accuracy on the majority of datasets sequences, while also having a lower runtime.
Out of place, out of time Marković, Ivan
Cultural geographies,
10/2019, Volume:
26, Issue:
4
Journal Article
Peer reviewed
Geography has in the last two decades showed an increasing interest in smoking and while mainly within the purview of health geographies, some have also utilised Foucauldian concepts of ...‘governmentality’ and Goffman’s notion of ‘stigma’ to study smoking’s spatial exclusion and purification of public spaces. More recently, cultural geographers have started to investigate the more embodied, sensory as well as affective elements of smoking. Notwithstanding recent developments, the temporalities of smoking have largely remained unaccounted for, while the more-than-human in smoking has received little sustained attention. This article aims to fill this gap and in doing so intervenes in this body of critical work by developing a framework that can account for the pharmacological and habitual affordances of smoking, without descending into the pathologisation of smoking bodies that has characterised a public health focus on the addictive qualities of nicotine. To develop this framework, the article brings theories of the more-than-human into dialogue with rhythmanalysis, in order to examine the messy human–nonhuman ties through which everyday rhythms of smoking are enacted, embodied and performed. By focusing on the spatio-temporal patterns of two nonhuman elements, nicotine and the cigarette, the aim is to dislodge the human body from the centre of analysis. This conceptual more-than-human rethinking of smoking offers a means to account for the agency and affects of nonhumans in relation to smoking, and addiction more broadly, without slipping back into deterministic, public health understandings of the body.
In this paper we propose a simultaneous localization and mapping (SLAM) back-end solution called the exactly sparse delayed state filter on Lie groups (LG-ESDSF). We derive LG-ESDSF and demonstrate ...that it retains all the good characteristics of the classic Euclidean ESDSF, the main advantage being the exact sparsity of the information matrix. The key advantage of LG-ESDSF in comparison with the classic ESDSF lies in the ability to respect the state space geometry by negotiating uncertainties and employing filtering equations directly on Lie groups. We also exploit the special structure of the information matrix in order to allow long-term operation while the robot is moving repeatedly through the same environment. To prove the effectiveness of the proposed SLAM solution, we conducted extensive experiments on two different publicly available datasets, namely the KITTI and EuRoC datasets, using two front-ends: one based on the stereo camera and the other on the 3D LIDAR. We compare LG-ESDSF with the general graph optimization framework (
g
2
o
) when coupled with the same front-ends. Similarly to
g
2
o
the proposed LG-ESDSF is front-end agnostic and the comparison demonstrates that our solution can match the accuracy of
g
2
o
, while maintaining faster computation times. Furthermore, the proposed back-end coupled with the stereo camera front-end forms a complete visual SLAM solution dubbed LG-SLAM. Finally, we evaluated LG-SLAM using the online KITTI protocol and at the time of writing it achieved the second best result among the stereo odometry solutions and the best result among the tested SLAM algorithms.
Despite human geography's sophisticated analyses and overwhelming focus on space, time in its various guises has certainly not been absent in the literature. The same cannot be said for historical ...geography, which is particularly interesting as its main concern is purportedly with space and place in and across other times. In response, this paper examines the ontology and epistemology of time in “modern” historical geography since the early 2000s and does so in discussion with recent developments in theory and philosophy of history, specifically the notion of ‘new presentism’. An idea which broadly posits that the past and the future do not exist as separate categories but are always projections of specific presents, they exist as the present's own immanent modes. This is achieved by adopting Robert Dodgshon's concept of the ‘specious present’ in order to (1) affirm, albeit on different epistemological grounds, the partiality, situatedness and contingency of historical geographies as well as the embodied and performative nature of archival labour; (2) offer an accessible conceptual tool in thinking about the role of time in the practice of future historical geography research; and finally (3) suggest that thinking historical geography as a practice in and through the ‘specious present’ makes questions of ethics, accountability, and politics of knowledge production both central and inevitable, as opposed to just being examples of “good practice” or worse still, being completely sidestepped by virtue of an imagined spatio-temporal distance between the bygone past and the present moment of research.
•Examines the ontology and epistemology of time in the subdiscipline of human geography.•Provides an explanation for the field's lack of engagement with time in its investigations.•Offers a onto-epistemic framework for incorporating the specious present in historical-geographical practice.
For all the economies in the global world the question of trade is becoming more important by the day. But the possibility to export on the global market meets many impediments in the form of ...non-tariff barriers, rather than tariff these days. CEFTA 2006 regional trade integration is not an exception with more than 100 NTBs introduced during its existence. Our research found that Serbia and Albania are CEFTA 2006 signatories with the most NTBs introduced in the observed period. CEFTA has a very efficient institutional mechanism, Subcommittee on Technical Barriers to Trade (TBT) and Non-Tariff Barriers (NTBs), for the removal of NTBs between signatories. We have researched three case studies of bilateral NTBs in Serbia’s intra-CEFTA 2006 which demonstrate that our trade partner uses policy oriented NTBs. The removal of NTBs at the global, as well as regional levels is crucial for the development of trade flows after the world economic crisis.
This paper explores the emergence of vaping (using e-cigarettes) as a nascent practice that is set to distinguish itself from smoking, yet one which is at the same time constrained by the same ...socio-cultural geographies of exclusion. Geographers have of late showed an interest in smoking but vaping has received little attention, and even beyond Geography, the burgeoning scholarship on the e-cigarette remains mostly within pharmacology and public health studies. This paper addresses these absences. The paper proposes an understanding of vaping as a skeuomorphic assemblage, which can help account for some of the discursive indeterminacy that stems from a design that, to a greater or lesser extent, mimics a practice that has been deemed a health, economic and moral hazard. Further, the example of vaping explored through the notion of skeuomorphism reveals that assemblages, and the bodies and technologies that constitute them are always social, political but above all historical. By drawing on an ethnographic study of vaping conducted in the UK, the paper examines how skeuomorphic assemblages gather between technology, body and the everyday physical and social environment. Bringing personal experience as a smoker to bear, it also considers the spatio-temporal, sensorial and embodied differences between smoking and vaping geographies.
Key Clinical Message
Alpha‐gal syndrome is an immunoglobulin E‐mediated hypersensitivity characterized by delayed allergic reactions to ingested products containing alpha‐gal carbohydrate. We present ...a patient with recurrent urticaria and suspected repaglinide hypersensitivity, who was eventually diagnosed with alpha‐gal syndrome, wanting to emphasize possible drug allergy misdiagnosis and required caution with the medication choice.
Alpha‐gal syndrome—Food or drug allergy: A case report .
•Human robot interaction is needed in modern warehouses.•Human intentions are estimated in industrial setup.•Experiments verified approach in augmented and virtual reality setups.
With the ...substantial growth of logistics businesses the need for larger warehouses and their automation arises, thus using robots as assistants to human workers is becoming a priority. In order to operate efficiently and safely, robot assistants or the supervising system should recognize human intentions in real-time. Theory of Mind (ToM) is an intuitive human conception of other humans’ mental state, i.e., beliefs and desires, and how they cause behavior. In this paper we propose a ToM based human intention estimation algorithm for flexible robotized warehouses. We observe human’s, i.e., worker’s motion and validate it with respect to the goal locations using generalized Voronoi diagram based path planning. These observations are then processed by the proposed hidden Markov model framework which estimates worker intentions in an online manner, capable of handling changing environments. To test the proposed intention estimation we ran experiments in a real-world laboratory warehouse with a worker wearing Microsoft Hololens augmented reality glasses. Furthermore, in order to demonstrate the scalability of the approach to larger warehouses, we propose to use virtual reality digital warehouse twins in order to realistically simulate worker behavior. We conducted intention estimation experiments in the larger warehouse digital twin with up to 24 running robots. We demonstrate that the proposed framework estimates warehouse worker intentions precisely and in the end we discuss the experimental results.
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