Dual exploration strategies using artificial spiking neural networks in a robotic learning task

2020 ◽  
pp. 105971232092474
Author(s):  
André Cyr ◽  
Julie Morand-Ferron ◽  
Frédéric Thériault
Keyword(s):  
Risk Taking ◽  
Spatial Information ◽  
Autonomous Robots ◽  
Visual Learning ◽  
Learning Task ◽  
Conditioning Procedure ◽  
Neural Architecture ◽  
The Common ◽  
Multiple Levels ◽  
Robotic Learning

Spatial information can be valuable, but new environments may be perceived as risky and thus often evoke fear responses and risk-averse exploration strategies such as thigmotaxis or wall-following behavior. Individual differences in risk-taking (boldness) and thigmotaxis have been reported in natural taxa, which may benefit their survival. In neurorobotic, the common approach is to reproduce cognitive phenomena with multiple levels of bio-inspiration into robotic scenarios. Since autonomous robots may benefit from these different behaviors in exploration tasks, this study aims at simulating two exploration strategies in a virtual robot controlled by a spiking neural network. The experimental context consists in a visual learning task solved through an operant conditioning procedure. Results suggest that the proposed neural architecture sustains both behaviors, switching from one to the other by external cues. This original bio-inspired model could be used as a first step toward further investigations of neurorobotic personality modulated by learning and complex exploration contexts.

scholarly journals Getting information on suspended sediments in a large river from acoustic backscatter

2018 ◽  
Vol 40 ◽  
pp. 04017
Author(s):  
Adrien Vergne ◽  
Céline Berni ◽  
Jérôme Le Coz
Keyword(s):  
Suspended Sediment Concentration ◽  
Spatial Information ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Large River ◽  
Acoustic Backscatter ◽  
Qualitative Information ◽  
Sediment Size ◽  
The Common

There has been a growing interest in the last decade in extracting information on Suspended Sediment Concentration (SSC) from acoustic backscatter in rivers. Quantitative techniques are not yet effective, but acoustic backscatter already provides qualitative information on suspended sediments. In particular, in the common case of a bi-modal sediment size distribution, corrected acoustic backscatter can be used to look for sand particles in suspension and provide spatial information on their distribution throughout a river crosssection. This paper presents a case-study where these techniques have been applied.

Severity of Ongoing Post-Concussive Symptoms as a Predictor of Cognitive Performance Following a Pediatric Mild Traumatic Brain Injury

2020 ◽  
pp. 1-11
Author(s):  
Veronik Sicard ◽  
Danielle C. Hergert ◽  
Sharvani Pabbathi Reddy ◽  
Cidney R. Robertson-Benta ◽  
Andrew B. Dodd ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Cognitive Performance ◽  
Mild Traumatic Brain Injury ◽  
Parental Education ◽  
Visual Learning ◽  
Learning Task ◽  
Risk Scores ◽  
Group Differences ◽  
Post Injury

Abstract Objective: This study aimed to examine the predictors of cognitive performance in patients with pediatric mild traumatic brain injury (pmTBI) and to determine whether group differences in cognitive performance on a computerized test battery could be observed between pmTBI patients and healthy controls (HC) in the sub-acute (SA) and the early chronic (EC) phases of injury. Method: 203 pmTBI patients recruited from emergency settings and 159 age- and sex-matched HC aged 8–18 rated their ongoing post-concussive symptoms (PCS) on the Post-Concussion Symptom Inventory and completed the Cogstate brief battery in the SA (1–11 days) phase of injury. A subset (156 pmTBI patients; 144 HC) completed testing in the EC (∼4 months) phase. Results: Within the SA phase, a group difference was only observed for the visual learning task (One-Card Learning), with pmTBI patients being less accurate relative to HC. Follow-up analyses indicated higher ongoing PCS and higher 5P clinical risk scores were significant predictors of lower One-Card Learning accuracy within SA phase, while premorbid variables (estimates of intellectual functioning, parental education, and presence of learning disabilities or attention-deficit/hyperactivity disorder) were not. Conclusions: The absence of group differences at EC phase is supportive of cognitive recovery by 4 months post-injury. While the severity of ongoing PCS and the 5P score were better overall predictors of cognitive performance on the Cogstate at SA relative to premorbid variables, the full regression model explained only 4.1% of the variance, highlighting the need for future work on predictors of cognitive outcomes.

scholarly journals The relationship between physiological arousal and multiple levels of temporal context in risky choice

2021 ◽  
Author(s):  
Hayley R. Brooks ◽  
Peter Sokol-Hessner
Keyword(s):  
Decision Making ◽  
Risk Taking ◽  
Context Effects ◽  
Temporal Structure ◽  
Physiological Arousal ◽  
Risky Choice ◽  
Context Dependency ◽  
Temporal Context ◽  
Multiple Levels ◽  
Task Level

Context-dependence is fundamental to risky monetary decision-making. A growing body of evidence suggests that temporal context, or recent events, alters risk-taking at a minimum of three timescales: immediate (e.g. trial-by-trial), neighborhood (e.g. a group of consecutive trials), and global (e.g. task-level). To examine context effects, we created a novel monetary choice set with intentional temporal structure in which option values shifted between multiple levels of value magnitude (“contexts”) several times over the course of the task. This structure allowed us to examine whether effects of each timescale were simultaneously present in risky choice behavior and the potential mechanistic role of arousal, an established correlate of risk-taking, in context-dependency. We found that risk-taking was sensitive to immediate, neighborhood, and global timescales, increasing following small (vs. large) outcome amounts, large positive (but not negative) shifts in context, and when cumulative earnings exceeded expectations. We quantified arousal with skin conductance responses, which were specifically related to the global timescale, increasing with cumulative earnings, suggesting that physiological arousal captures a task-level assessment of performance. We complimented this correlational analysis with a secondary reanalysis of risky monetary choices following the double-blind administration of propranolol and a placebo during a temporally unstructured choice task. We replicated our behavioral finding that risk-taking is context-sensitive at three timescales but found no change in temporal context-effects following propranolol administration. Our results demonstrate that risky decision-making is consistently dynamic at multiple timescales and that arousal is likely the consequence, rather than the cause, of temporal context in risky monetary decision-making.

scholarly journals Converting Molecular Meshes Into Smooth Interpolatory Spline Solid Models

2005 ◽  
Author(s):  
Joel Daniels ◽  
Elaine Cohen ◽  
David Johnson
Keyword(s):  
Continuous Model ◽  
Multiple Components ◽  
Spline Models ◽  
Solid Models ◽  
Spline Surfaces ◽  
Physical Form ◽  
Cad Cam ◽  
The Common ◽  
Rectangular Grids ◽  
Multiple Levels

The study and understanding of molecules, once the domain of blackboards and stick-and-ball models, has become more and more exclusively linked to the use of computer-aided visualizations. Our project seeks to return the physical facsimile to the biologists, allowing the use of tactile senses while interacting with and manipulating a physical model, thus aiding educational and research endeavors. To increase the effectiveness of such a tool, the model is constructed such that multiple levels of information are viewable within the single physical form, stressing the interaction between the assorted components within the molecule. We use the term 3-D physical visualizations to refer to the fabricated model, to avoid confusion with the common usage of model as a virtual representation on the computer. To effectively combine multiple components into a smooth manufacturable physical visualization, all components of the model must be in a homogeneous format. Our research sets forth a method for converting triangulated mesh data, as provided by the molecular modeling packages, into spline models. Spline models have the attractive qualities that they are smooth without triangular facets, can be combined using traditional boolean operations (and, or, not), and can be directly fabricated using modern CAD/CAM techniques. Our method divides the polyhedral representation into multiple rectangular grids, then fits interpolatory spline surfaces to the data in each region, while focusing on smoothly stitching the boundaries and corners of the spline surfaces in order to create a near G1 continuous model.

scholarly journals Financial Twilight Re-Appraisal: Ending the Judicially Created Quagmire of Fiduciary Duties to Creditors

2017 ◽  
Vol 78 (2) ◽  
Author(s):  
Anil Hargovan ◽  
Timothy M. Todd
Keyword(s):  
Risk Taking ◽  
Financial Distress ◽  
The United States ◽  
Corporate Law ◽  
Fiduciary Duty ◽  
Fiduciary Duties ◽  
Financial Interests ◽  
The Common ◽  
Corporate Rescue ◽  
Judicial Recognition

Directors owe fiduciary duties of care and loyalty to their corporations, and by extension to their shareholders. When a corporation approaches or enters insolvency, however, courts have recently found that the fiduciary duty calculus may change. Recognizing that creditors have financial interests similar to those of shareholders at or near insolvency, courts in several countries have extended fiduciary duty protection to creditors on equitable grounds. This trend has led to a state of flux and uncertainty in corporate law. Consequently, courts and commentators are battling to fully comprehend the controversial subject of director fiduciary duties to creditors in various jurisdictions. Due to this jurisprudential flux, unresolved issues include, for example, the core notion that the duty arises when the company enters into an “ill-defined sphere” known as the “zone” or “vicinity” of insolvency. The law is remarkably short of specific judicial guidance as to how directors who engage in commercial risk-taking with a view to corporate rescue should discharge their duties without harming the interests of creditors. Indeed, the debate continues even on the critical doctrinal question of whether such a duty is even needed.This Article uses corporate law in both the United States and Australia as emblematic of the real practical concerns inherent in the expansion of fiduciary duties. Consequently, the Article argues that the judicial recognition of directors’ fiduciary duties to creditors when at or near insolvency is objectionable, both from a policy and a doctrinal standpoint, and that any further attempt to develop the common law in this regard should be jettisoned in favor of reliance upon the existing, or modified, statutory regime aimed at creditor protection during times of financial distress. 

scholarly journals PMK—A Knowledge Processing Framework for Autonomous Robotics Perception and Manipulation

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1166 ◽  
Author(s):  
Mohammed Diab ◽  
Aliakbar Akbari ◽  
Muhayy Ud Din ◽  
Jan Rosell
Keyword(s):  
Information Exchange ◽  
Spatial Information ◽  
Autonomous Robots ◽  
Semantic Knowledge ◽  
Geometric Constraints ◽  
Service Robots ◽  
Autonomous Robotics ◽  
Knowledge Processing ◽  
Processing Framework ◽  
The Way

Autonomous indoor service robots are supposed to accomplish tasks, like serve a cup, which involve manipulation actions. Particularly, for complex manipulation tasks which are subject to geometric constraints, spatial information and a rich semantic knowledge about objects, types, and functionality are required, together with the way in which these objects can be manipulated. In this line, this paper presents an ontological-based reasoning framework called Perception and Manipulation Knowledge (PMK) that includes: (1) the modeling of the environment in a standardized way to provide common vocabularies for information exchange in human-robot or robot-robot collaboration, (2) a sensory module to perceive the objects in the environment and assert the ontological knowledge, (3) an evaluation-based analysis of the situation of the objects in the environment, in order to enhance the planning of manipulation tasks. The paper describes the concepts and the implementation of PMK, and presents an example demonstrating the range of information the framework can provide for autonomous robots.

TRADITIONAL VALUES IN THE ERA OF TECHNOLOGY AND INNOVATION

2019 ◽  
Vol 1 ◽  
pp. 320
Author(s):  
Urve Läänemets ◽  
Katrin Kalamees-Ruubel ◽  
Anu Sepp ◽  
Kristi Kiilu
Keyword(s):  
Learning Environments ◽  
Comparative Research ◽  
Music Teachers ◽  
Traditional Values ◽  
Technology And Innovation ◽  
International Trends ◽  
Personal Experiences ◽  
The Common ◽  
Multiple Levels ◽  
Cultural Cohesion

Several factors, such as international trends of globalisation, technological innovation, changing learning environments as well as internal developments in socio-cultural contexts and educational policy-making are constantly shaping values of people and causing difficulties with specification of their identity building. Our study is based on comparative research carried out in Estonia and Finland in 2015-2018 (N = 217) with future music teachers, who were asked to write essays where they highlighted and explained meaningful for them cultural landmarks in their countries. The method used was hermeneutical analysis, as this allows to focus on the text produced according to the question asked as an expression of the respondents’ personal experiences and accepted values. The information presented in texts was analyzed at multiple levels and different viewpoints. Parallel analyses by authors were carried out in order to guarantee the validity of the overall results. Finally, the results were grouped, which allowed to draw preliminary conclusions what the common cultural landmarks were and why they have been accepted  and recognised  as meaningful and valuable by future music teachers both in Estonia and Finland and what their potential could be developing cultural cohesion in society.  

scholarly journals Digital Heritage

2019 ◽  
pp. 565-591
Author(s):  
Xinyuan Wang ◽  
Rosa Lasaponara ◽  
Lei Luo ◽  
Fulong Chen ◽  
Hong Wan ◽  
...  
Keyword(s):  
Cultural Heritage ◽  
Spatial Information ◽  
Applied Theory ◽  
Practical Case ◽  
Human Beings ◽  
Digital Heritage ◽  
Human Understanding ◽  
Protection And Utilization ◽  
The Common ◽  
Spatial Information Technology

Abstract Natural and cultural heritage, the common wealth of human beings, are keys to human understanding of the evolution of our planet and social development. The protection and conservation of natural and cultural heritage is the common responsibility of all mankind. Spatial information technology provides a new applied theory and tool for the protection and utilization of natural and cultural heritage. This chapter is divided into four parts. The first part elaborates the connotation of digital heritage, the differences and connections between digital heritage and physical heritage, the technology of digital heritage formation and the research objectives and content of digital heritage. Parts 2 and 3 discuss the contents and methods of digital natural heritage and cultural heritage, respectively, and some practical case studies. In the fourth part, the future development trends of digital heritage research in protection and utilization are described, as well as six research directions that deserve attention.

scholarly journals Spatial tuning and brain state account for dorsal hippocampal CA1 activity in a non-spatial learning task

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Kevin Q Shan ◽  
Evgueniy V Lubenov ◽  
Maria Papadopoulou ◽  
Athanassios G Siapas
Keyword(s):  
Spatial Learning ◽  
Pyramidal Neurons ◽  
Spatial Information ◽  
Eyeblink Conditioning ◽  
Brain Area ◽  
Learning Task ◽  
Spatial Task ◽  
Place Cells ◽  
Brain State ◽  
Output Stages

The hippocampus is a brain area crucial for episodic memory in humans. In contrast, studies in rodents have highlighted its role in spatial learning, supported by the discovery of place cells. Efforts to reconcile these views have found neurons in the rodent hippocampus that respond to non-spatial events but have not unequivocally dissociated the spatial and non-spatial influences on these cells. To disentangle these influences, we trained freely moving rats in trace eyeblink conditioning, a hippocampally dependent task in which the animal learns to blink in response to a tone. We show that dorsal CA1 pyramidal neurons are all place cells, and do not respond to the tone when the animal is moving. When the animal is inactive, the apparent tone-evoked responses reflect an arousal-mediated resumption of place-specific firing. These results suggest that one of the main output stages of the hippocampus transmits only spatial information, even in this non-spatial task.

scholarly journals WALKING WALKing walking: Action Recognition from Action Echoes

2017 ◽  
Author(s):  
Qianli Ma ◽  
Lifeng Shen ◽  
Enhuan Chen ◽  
Shuai Tian ◽  
Jiabing Wang ◽  
...  
Keyword(s):  
Time Series ◽  
Spatial Information ◽  
Multivariate Time Series ◽  
Learning Task ◽  
Physical Structure ◽  
Data Sets ◽  
Benchmark Data ◽  
Echo State Networks ◽  
History Of ◽  
Label Distribution

Recognizing human actions represented by 3D trajectories of skeleton joints is a challenging machine learning task. In this paper, the 3D skeleton sequences are regarded as multivariate time series, and their dynamics and multiscale features are efficiently learned from action echo states. Specifically, first the skeleton data from the limbs and trunk are projected into five high dimensional nonlinear spaces, that are randomly generated by five dynamic, training-free recurrent networks, i.e., the reservoirs of echo state networks (ESNs). In this way, the history of the time series is represented as nonlinear echo states of actions. We then use a single multiscale convolutional layer to extract multiscale features from the echo states, and maintain multiscale temporal invariance by a max-over-time pooling layer. We propose two multi-step fusion strategies to integrate the spatial information over the five parts of the human physical structure. Finally, we learn the label distribution using softmax. With one training-free recurrent layer and only layer of convolution, our Convolutional Echo State Network (ConvESN) is a very efficient end-to-end model, and achieves state-of-the-art performance on four skeleton benchmark data sets.

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