scholarly journals An Integrated Strategy for Autonomous Exploration of Spatial Processes in Unknown Environments

Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3663
Author(s):  
Valentina Karolj ◽  
Alberto Viseras ◽  
Luis Merino ◽  
Dmitriy Shutin
Keyword(s):  
A Priori ◽  
Real Life ◽  
Spatial Process ◽  
Spatial Processes ◽  
Simulated Environments ◽  
Robotic Exploration ◽  
Integrated Strategy ◽  
Holonomic Robot ◽  
Robotic Applications ◽  
Conflicting Goals

Exploration of spatial processes, such as radioactivity or temperature is a fundamental task in many robotic applications. In the literature, robotic exploration is mainly carried out for applications where the environment is a priori known. However, for most real life applications this assumption often does not hold, specifically for disaster scenarios. In this paper, we propose a novel integrated strategy that allows a robot to explore a spatial process of interest in an unknown environment. To this end, we build upon two major blocks. First, we propose the use of GP to model the spatial process of interest, and process entropy to drive the exploration. Second, we employ registration algorithms for robot mapping and localization, and frontier-based exploration to explore the environment. However, map and process exploration can be conflicting goals. Our integrated strategy fuses the two aforementioned blocks through a trade-off between process and map exploration. We carry out extensive evaluations of our algorithm in simulated environments with respect to different baselines and environment setups using simulated GP data as a process at hand. Additionally, we perform experimental verification with a mobile holonomic robot exploring a simulated process in an unknown labyrinth environment. Demonstrated results show that our integrated strategy outperforms both frontier-based and GP entropy-driven exploration strategies.

scholarly journals A Systematic Review and Qualitative Synthesis Resulting in a Typology of Elementary Classroom Movement Integration Interventions

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Spyridoula Vazou ◽  
Collin A. Webster ◽  
Gregory Stewart ◽  
Priscila Candal ◽  
Cate A. Egan ◽  
...  
Keyword(s):  
Physical Activity ◽  
Teacher Collaboration ◽  
A Priori ◽  
Real Life ◽  
Dose Intensity ◽  
Routine Practice ◽  
Qualitative Synthesis ◽  
Wide Range ◽  
Meta Analyses ◽  
Movement Integration

Abstract Background/Objective Movement integration (MI) involves infusing physical activity into normal classroom time. A wide range of MI interventions have succeeded in increasing children’s participation in physical activity. However, no previous research has attempted to unpack the various MI intervention approaches. Therefore, this study aimed to systematically review, qualitatively analyze, and develop a typology of MI interventions conducted in primary/elementary school settings. Subjects/Methods Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to identify published MI interventions. Irrelevant records were removed first by title, then by abstract, and finally by full texts of articles, resulting in 72 studies being retained for qualitative analysis. A deductive approach, using previous MI research as an a priori analytic framework, alongside inductive techniques were used to analyze the data. Results Four types of MI interventions were identified and labeled based on their design: student-driven, teacher-driven, researcher-teacher collaboration, and researcher-driven. Each type was further refined based on the MI strategies (movement breaks, active lessons, other: opening activity, transitions, reward, awareness), the level of intrapersonal and institutional support (training, resources), and the delivery (dose, intensity, type, fidelity). Nearly half of the interventions were researcher-driven, which may undermine the sustainability of MI as a routine practice by teachers in schools. An imbalance is evident on the MI strategies, with transitions, opening and awareness activities, and rewards being limitedly studied. Delivery should be further examined with a strong focus on reporting fidelity. Conclusions There are distinct approaches that are most often employed to promote the use of MI and these approaches may often lack a minimum standard for reporting MI intervention details. This typology may be useful to effectively translate the evidence into practice in real-life settings to better understand and study MI interventions.

scholarly journals Drone Deep Reinforcement Learning: A Review

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 999
Author(s):  
Ahmad Taher Azar ◽  
Anis Koubaa ◽  
Nada Ali Mohamed ◽  
Habiba A. Ibrahim ◽  
Zahra Fathy Ibrahim ◽  
...  
Keyword(s):  
Reinforcement Learning ◽  
State Of The Art ◽  
Real Life ◽  
Environment Monitoring ◽  
Simulated Environments ◽  
Infrastructure Inspection ◽  
Remote Sensing Mapping ◽  
And Control ◽  
The Military ◽  
Uav Navigation

Unmanned Aerial Vehicles (UAVs) are increasingly being used in many challenging and diversified applications. These applications belong to the civilian and the military fields. To name a few; infrastructure inspection, traffic patrolling, remote sensing, mapping, surveillance, rescuing humans and animals, environment monitoring, and Intelligence, Surveillance, Target Acquisition, and Reconnaissance (ISTAR) operations. However, the use of UAVs in these applications needs a substantial level of autonomy. In other words, UAVs should have the ability to accomplish planned missions in unexpected situations without requiring human intervention. To ensure this level of autonomy, many artificial intelligence algorithms were designed. These algorithms targeted the guidance, navigation, and control (GNC) of UAVs. In this paper, we described the state of the art of one subset of these algorithms: the deep reinforcement learning (DRL) techniques. We made a detailed description of them, and we deduced the current limitations in this area. We noted that most of these DRL methods were designed to ensure stable and smooth UAV navigation by training computer-simulated environments. We realized that further research efforts are needed to address the challenges that restrain their deployment in real-life scenarios.

scholarly journals Transformation of Uncertain Linear Systems with Real Eigenvalues into Cooperative Form: The Case of Constant and Time-Varying Bounded Parameters

Algorithms ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 85
Author(s):  
Andreas Rauh ◽  
Julia Kersten
Keyword(s):  
Linear Systems ◽  
Initial Conditions ◽  
A Priori ◽  
Real Life ◽  
Reachability Analysis ◽  
Interval Methods ◽  
Space Representation ◽  
Uncertain Parameters ◽  
Time Varying ◽  
Similarity Transformations

Continuous-time linear systems with uncertain parameters are widely used for modeling real-life processes. The uncertain parameters, contained in the system and input matrices, can be constant or time-varying. In the latter case, they may represent state dependencies of these matrices. Assuming bounded uncertainties, interval methods become applicable for a verified reachability analysis, for feasibility analysis of feedback controllers, or for the design of robust set-valued state estimators. The evaluation of these system models becomes computationally efficient after a transformation into a cooperative state-space representation, where the dynamics satisfy certain monotonicity properties with respect to the initial conditions. To obtain such representations, similarity transformations are required which are not trivial to find for sufficiently wide a-priori bounds of the uncertain parameters. This paper deals with the derivation and algorithmic comparison of two different transformation techniques for which their applicability to processes with constant and time-varying parameters has to be distinguished. An interval-based reachability analysis of the states of a simple electric step-down converter concludes this paper.

Kriterien der ethnischen Identität

1983 ◽  
Vol 7 (1) ◽  
pp. 21-42
Author(s):  
Harald Haarmann
Keyword(s):  
Ethnic Identity ◽  
A Priori ◽  
Real Life ◽  
Problem Area ◽  
Methodological Issues ◽  
Large Measure ◽  
Individual Features ◽  
The One ◽  
The Individual

SUMMARY Criteria for Ethnic Identity Despite numerous publications on theoretical and methodological issues regarding ethnic identity (ethnicity), many methodological problems relative to this topic remain insufficiently clarified. This article deals particularly with the problems involved in establishing and evaluating criteria of ethnic identity. The author assigns the complex of problems regarding ethnic identity significant status within a theory of the ecology of language. Specific points covered in methodological issues involving the formation of concepts and application of terminology involve: 1. problems of the weighting of distinctive features; 2. problems in the mutual boundary-marking between ethnic groups (i.e., problems of ethnic borders); 3. problems in the changeability of ethnic identity; 4. problems in the correlation of language and ethnicity; 5. problems of the polarity of subjective and objective features of ethnicity; 6. problems of multiple identities and the role of ethnic identity; 7. problems in the historical dimension of ethnic identity; 8. problems in the linking of groups within language communities of the same national identity. In international sociological and sociolinguistic research, unanimity of opinion exists only on the fact that ethnic identity cannot be characterized by a single feature but rather by a series of individual features (the accumulation of features). The priorities to be attached to the individual features are in large measure disputed. The author proceeds from the assumption that ethnic identities in real life are formed through a stronger or weaker dominance of individual features; they should be characterized accordingly. An unacceptable a priori evaluation or weighting of features is thus avoided. In the specific context of a long-term research program on the smaller language communities and ethnic languages of Europe, the author particularly examines the role of language in ethnicity. Contrary to most previous contributions to discussions of this problem area, the author distinguishes between the general linguistic affiliation as a characteristic of ethnic identity on the one hand (cf. the relationship in point 4) and the criterion of language-oriented group formations (cf. relationship in point 8). The problem area of the principle of language community is illustrated using the example of the Transcarpathian Gypsies in the Ukraine. RESUMO Kriterioj de la etna idento Malgraŭ multaj ĝisnunaj eldonajoj pri la etna idento (etneco), multaj metodaj pro-blemoj rilataj al tiu temaro restas nesufice klarigitaj. La jena artikolo aparte traktas la problemaron de la starigo kaj elvalorigo de kriterioj de la etna idento. La autoro al-jugas al la problemaro pri la etna idento gravan rangon interne de teorio pri la lingva ekologio. Apartaj punktoj, traktitaj en metodaraj demandoj, rilataj al la formado de konceptoj kaj la apliko de terminaro, estas: 1. problemaro pri la elvalorigo de karakteraj trajtoj; 2. problemaro de la reciproka limigo inter etnaj grupoj (t.e. problemoj pri etnaj limoj); 3. problemaro pri la šanĝebleco de la etna idento; 4. problemaro pri la rilato inter lingvo kaj etneco; 5. problemaro pri la polusigo de subjektivaj kaj objektivaj trajtoj de etneco; 6. problemaro de pluroblaj identoj kaj la rolo de etna idento; 7. problemaro ce la historia dimensio de la etna idento; 8. problemaro de la formiĝo de grupoj interne de lingvaj komunumoj de la sama nacia idento. En la internacia sociologia kaj socilingvistika esplorado, unuanimeco de opinio ekzistas nur pri la fakto, ke ne eblas karakterizi la etnan identon nur per unusola trajto, sed, male, per aro da opaj trajtoj (la kuniĝo de trajtoj). Oni grandparte disputas pri la prioritato, kiun oni aljuĝu al la opaj trajtoj. La autoro progresas ek de la asumo, ke la etnaj identoj en la vera vivo estas formitaj per, jen pli forta, jen pli malforta, rego de opaj trajtoj; oni karakterizu ilin lau tio. Tiel, oni evitas neakceptindan aprioran elvalorigon au elpezigon de trajtoj. En la aparta kunteksto de longdaura esplorprogramo pri la pli malgrandaj lingvaj komunumoj kaj etnaj lingvoj de Europo, la autoro aparte pristudas la rolon de la lingvo ce la etneco. Kontraue al la plejmultaj ĝisnunaj kontribuoj al diskutoj pri tiu problemaro, la autoro distingas inter la ĝenerala lingva aparteno kiel trajto de la etna idento unuflanke (komparu la rilton ce punkto 4) kaj la kriterion de la formigo de grupoj surbaze de lingvo (komparu la rilaton ce punkto 8). La problemaro de la prin-cipo de la lingva komunumo estas ilustrita per la ekzemplo de la transkarpataj ciganoj en Ukrajnio.

Modified Nernst-Plank-Poisson Model for IPMC With Back-Relaxation Effects

2019 ◽  
Author(s):  
Aiman Al-Allaq ◽  
Nebojsa Jaksic ◽  
Bahaa Ansaf ◽  
Jude DePalma ◽  
Trung Duong
Keyword(s):  
Controller Design ◽  
Real Life ◽  
Poisson Model ◽  
Great Accuracy ◽  
Metal Composite ◽  
New Model ◽  
Relaxation Effects ◽  
Wide Range ◽  
Polymer Metal ◽  
Robotic Applications

Abstract The ionic polymer–metal composite (IPMC) is a new practical engineering material that, it has a wide range of capabilities in both dry and liquid environments. IPMC is a new candidate for diaphragms in micropump devices, micro and Nano robotic applications. IPMCs are regarded as a capable actuator for transportable applications, however, the unique combination of electrochemical and mechanical properties that they possess, such as back-relaxation, restraint their use in real-life applications. There have a lot of attempts to understand and model the IPMCs properties and build a whole prototype that can be used, with certainty, in different robotic, control, and medical applications, yet, till now, it seems that the dehydration and back-relaxation are still not modeled properly. The Nernst-Plank-Poisson was chosen to be the base model for the IPMC behavior, we were able to create a new model that truly represent the back-relaxation effects that occur in IPMCs, we’ve called the new model as modified NPP model. The modification used captured data from our experimental work Our modified analytical NPP (Nernst-Plank-Poisson) model was the verified using MATLAB & Simulink, which showed that the model, and the controller design for it was able to first compensate the loss of position of the IPMC due to back-relaxation, and then track the desired position input signals with great accuracy. The model and designed controller can be utilized in verity of robotic applications.

scholarly journals Using Sociological Images to Develop the Sociological Imagination

2021 ◽  
pp. 0092055X2110545
Author(s):  
Georgiana Bostean ◽  
Lisa Leitz
Keyword(s):  
A Priori ◽  
Student Assessment ◽  
Real Life ◽  
Learning Goals ◽  
Visual Images ◽  
Online Course ◽  
Face To Face ◽  
Social Events ◽  
Regional University ◽  
Lower Division

We present a two-assignment series that developed students’ sociological imaginations and that could be done in a face-to-face or online course. The series used the Sociological Images blog and students’ own visual images (e.g., photographs) to meet course learning goals: (1) link sociological theories and concepts to social events/trends, (2) apply these ideas to real life by identifying sociologically relevant images in daily life, and (3) communicate sociological analysis in academic and popular written forms. The use of a blog encourages students to embrace public sociology. We present faculty and student assessment data (pretest from nonequivalent comparisons group) from six lower division sociology classes at a regional university (N = 157). Students entered with little a priori ability to examine images using a sociological lens, and students who completed the series successfully applied sociological concepts and theories to critically examine elements of their lives, achieving core sociology disciplinary learning goals.

scholarly journals Evolutionary Game for Confidentiality in IoT-enabled Smart Grids

2020 ◽  
Author(s):  
Svetlana Boudko ◽  
Peder Aursand ◽  
Habtamu Abie
Keyword(s):  
Game Theory ◽  
Evolutionary Game Theory ◽  
Smart Grids ◽  
A Priori ◽  
Evolutionary Game ◽  
Real Life ◽  
Advanced Metering Infrastructure ◽  
A Priori Analysis ◽  
Advanced Metering ◽  
Security Game

We applied evolutionary game theory to extend a resource constrained security game model for confidentiality attacks in an Advanced Metering Infrastructure (AMI), which is a component of IoT-enabled Smart Grids. The AMI is modelled as a tree structure where each node aggregates the information of its children before encrypting it and passing it on to its parent. As a part of the model, we developed a discretization scheme for solving the replicator equations. The aim of this work is to explore the space of possible behaviours of attackers and to develop a framework where the AMI nodes adaptively select the most profitable strategies. Using this model, we simulated the evolution of a population of attackers and defenders on various cases resembling the real life implementation of AMI. We discuss in depth how to enhance security in AMI using evolutionary game theory either by a priori analysis or as a tool to run dynamic and adaptive infrastructure defence.

scholarly journals Seismic Constrained Gravity Inversion: A Reliable Tool to Improve Geophysical Models Away from Seismic Information

Geosciences ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 467
Author(s):  
Daniele Sampietro ◽  
Martina Capponi
Keyword(s):  
High Resolution ◽  
Gravity Field ◽  
A Priori ◽  
Geophysical Methods ◽  
Real Life ◽  
Gravity Inversion ◽  
Seismic Surveys ◽  
Real Model ◽  
Gravity Fields ◽  
Priori Information

The exploitation of gravity fields in order to retrieve information about subsurface geological structures is sometimes considered a second rank method, in favour of other geophysical methods, such as seismic, able to provide a high resolution detailed picture of the main geological horizons. Within the current work we prove, through a realistic synthetic case study, that the gravity field, thanks to the availability of freely of charge high resolution global models and to the improvements in the gravity inversion methods, can represent a valid and cheap tool to complete and enhance geophysical modelling of the Earth’s crust. Three tests were carried out: In the first one a simple two-layer problem was considered, while in tests two and three we considered two more realistic scenarios in which the availability on the study area of constraints derived from 3D or 2D seismic surveys were simulated. In all the considered test cases, in which we try to simulate real-life scenarios, the gravity field, inverted by means of an advanced Bayesian technique, was able to obtain a final solution closer to the (simulated) real model than the assumed a priori information, typically halving the uncertainties in the geometries of the main geological horizons with respect to the initial model.

scholarly journals The context of experienced sensory discrepancies shapes multisensory integration and recalibration differently

2021 ◽  
Author(s):  
Hame Park ◽  
Christoph Kayser
Keyword(s):  
Multisensory Integration ◽  
A Priori ◽  
Real Life ◽  
Context Sensitivity ◽  
Multisensory Perception ◽  
Common Source ◽  
Sensory Level ◽  
Inference Models ◽  
Ventriloquism Aftereffect ◽  
Adaptive Nature

Whether two sensory cues interact during perceptual judgments depends on their immediate properties, but as suggested by Bayesian models, also on the observer's a priori belief that these originate from a common source. While in many experiments this a priori belief is considered fixed, in real life it must adapt to the momentary context or environment. To understand the adaptive nature of human multisensory perception we investigated the context-sensitivity of spatial judgements in a ventriloquism paradigm. We exposed observers to audio-visual stimuli whose discrepancy either varied over a wider (±46°) or a narrower range (±26°) and hypothesized that exposure to a wider range of discrepancies would facilitate multisensory binding by increasing participants a priori belief about a common source for a given discrepancy. Our data support this hypothesis by revealing an enhanced integration (ventriloquism) bias in the wider context, which was echoed in Bayesian causal inference models fit to participants' data, which assigned a stronger a priori integration tendency during the wider context. Interestingly, the immediate ventriloquism aftereffect, a multisensory response bias obtained following a multisensory test trial, was not affected by the contextual manipulation, although participants' confidence in their spatial judgments differed between contexts for both integration and recalibration trials. These results highlight the context-sensitivity of multisensory binding and suggest that the immediate ventriloquism aftereffect is not a purely sensory-level consequence of the multisensory integration process.

scholarly journals How I manage the toxicities of myeloma drugs

Blood ◽  
2017 ◽  
Vol 129 (17) ◽  
pp. 2359-2367 ◽  
Author(s):  
Michel Delforge ◽  
Heinz Ludwig
Keyword(s):  
Monoclonal Antibodies ◽  
Side Effects ◽  
Adverse Events ◽  
Day Treatment ◽  
A Priori ◽  
Proteasome Inhibitors ◽  
Real Life ◽  
Treatment Decision ◽  
Short Term Treatment ◽  
Treatment Regimens

AbstractThe treatment of multiple myeloma is considered a continuously evolving paradigm as a result of the growing availability of new and highly effective drugs, including first- and second-generation proteasome inhibitors, immunomodulatory agents, and monoclonal antibodies. Clinical trials advocate long-term rather than short-term treatment schedules with combinations of these new anti–myeloma drug classes. Although the overall toxicity profile of the recommended regimens can be considered favorable, their increasing complexity and prolonged use warrant a heightened vigilance for early and late side effects, a priori because real-life patients can be more frail or present with 1 or more comorbidities. The treatment decision process, at diagnosis and at relapse, therefore requires myeloma physicians to carefully balance efficacy and toxicity profiles for each individual patient. Early and/or unnecessary tapering or treatment discontinuation for drug-related adverse events may not only reduce patients’ quality of life, but also negatively impact their outcome. Accurate knowledge in recognizing and managing the potential side effects of present-day treatment regimens is therefore a cornerstone in myeloma care. Using 5 case vignettes, we discuss how to prevent and manage the most common nonhematological adverse events of anti–myeloma treatment regimens containing proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies.

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