scholarly journals A Comparative Study of Bio-Inspired Odour Source Localisation Strategies from the State-Action Perspective

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2231 ◽  
Author(s):  
João Macedo ◽  
Lino Marques ◽  
Ernesto Costa
Keyword(s):  
Real World ◽  
Evolutionary Robotics ◽  
Perceptual State ◽  
State Action ◽  
Odour Source ◽  
Candidate Solution ◽  
Real World Applications ◽  
Statistical Hypotheses ◽  
Odour Dispersion

Locating odour sources with robots is an interesting problem with many important real-world applications. In the past years, the robotics community has adapted several bio-inspired strategies to search for odour sources in a variety of environments. This work studies and compares some of the most common strategies from a behavioural perspective with the aim of knowing: (1) how different are the behaviours exhibited by the strategies for the same perceptual state; and (2) which are the most consensual actions for each perceptual state in each environment. The first step of this analysis consists of clustering the perceptual states, and building histograms of the actions taken for each cluster. In case of (1), a histogram is made for each strategy separately, whereas for (2), a single histogram containing the actions of all strategies is produced for each cluster of states. Finally, statistical hypotheses tests are used to find the statistically significant differences between the behaviours of the strategies in each state. The data used for performing this study was gathered from a purpose-built simulator which accurately simulates the real-world phenomena of odour dispersion and air flow, whilst being sufficiently fast to be employed in learning and evolutionary robotics experiments. This paper also proposes an xml-inspired structure for the generated datasets that are used to store the perceptual information of the robots over the course of the simulations. These datasets may be used in learning experiments to estimate the quality of a candidate solution or for measuring its novelty.

scholarly journals Unsupervised Quality Estimation for Neural Machine Translation

2020 ◽  
Vol 8 ◽  
pp. 539-555
Author(s):  
Marina Fomicheva ◽  
Shuo Sun ◽  
Lisa Yankovskaya ◽  
Frédéric Blain ◽  
Francisco Guzmán ◽  
...  
Keyword(s):  
Machine Translation ◽  
Real World ◽  
State Of The Art ◽  
Black Box ◽  
Test Time ◽  
Quality Estimation ◽  
Neural Machine Translation ◽  
Real World Applications ◽  
Unsupervised Approach

Quality Estimation (QE) is an important component in making Machine Translation (MT) useful in real-world applications, as it is aimed to inform the user on the quality of the MT output at test time. Existing approaches require large amounts of expert annotated data, computation, and time for training. As an alternative, we devise an unsupervised approach to QE where no training or access to additional resources besides the MT system itself is required. Different from most of the current work that treats the MT system as a black box, we explore useful information that can be extracted from the MT system as a by-product of translation. By utilizing methods for uncertainty quantification, we achieve very good correlation with human judgments of quality, rivaling state-of-the-art supervised QE models. To evaluate our approach we collect the first dataset that enables work on both black-box and glass-box approaches to QE.

scholarly journals Towards Fast Plume Source Estimation with a Mobile Robot

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7025
Author(s):  
Hugo Magalhães ◽  
Rui Baptista ◽  
João Macedo ◽  
Lino Marques
Keyword(s):  
Mobile Robot ◽  
Particle Filter ◽  
Computational Cost ◽  
Solution Space ◽  
Odour Source ◽  
Source Term Estimation ◽  
Gaussian Plume ◽  
Odour Dispersion ◽  
Instantaneous Concentration

The estimation of the parameters of an odour source is of high relevance for multiple applications, but it can be a slow and error prone process. This work proposes a fast particle filter-based method for source term estimation with a mobile robot. Two strategies are implemented in order to reduce the computational cost of the filter and increase its accuracy: firstly, the sampling process is adapted by the mobile robot in order to optimise the quality of the data provided to the estimation process; secondly, the filter is initialised only after collecting preliminary data that allow limiting the solution space and use a shorter number of particles than it would be normally necessary. The method assumes a Gaussian plume model for odour dispersion. This models average odour concentrations, but the particle filter was proved adequate to fit instantaneous concentration measurements to that model, while the environment was being sampled. The method was validated in an obstacle free controlled wind tunnel and the validation results show its ability to quickly converge to accurate estimates of the plume’s parameters after a reduced number of plume crossings.

scholarly journals Imperceptible–Visible Watermarking to Information Security Tasks in Color Imaging

Mathematics ◽  
2021 ◽  
Vol 9 (19) ◽  
pp. 2374
Author(s):  
Oswaldo Ulises Juarez-Sandoval ◽  
Francisco Javier Garcia-Ugalde ◽  
Manuel Cedillo-Hernandez ◽  
Jazmin Ramirez-Hernandez ◽  
Leobardo Hernandez-Gonzalez
Keyword(s):  
Real World ◽  
Copyright Protection ◽  
Color Image ◽  
Image Watermarking ◽  
Additional Information ◽  
Visible Watermarking ◽  
Real World Applications ◽  
Digital Reproduction ◽  
Two Stages

Digital image watermarking algorithms have been designed for intellectual property, copyright protection, medical data management, and other related fields; furthermore, in real-world applications such as official documents, banknotes, etc., they are used to deliver additional information about the documents’ authenticity. In this context, the imperceptible–visible watermarking (IVW) algorithm has been designed as a digital reproduction of the real-world watermarks. This paper presents a new improved IVW algorithm for copyright protection that can deliver additional information to the image content. The proposed algorithm is divided into two stages: in the embedding stage, a human visual system-based strategy is used to embed an owner logotype or a 2D quick response (QR) code as a watermark into a color image, maintaining a high watermark imperceptibility and low image-quality degradation. In the exhibition, a new histogram binarization function approach is introduced to exhibit any watermark with enough quality to be recognized or decoded by any application, which is focused on reading QR codes. The experimental results show that the proposed algorithm can embed one or more watermark patterns, maintaining the high imperceptibility and visual quality of the embedded and the exhibited watermark. The performance evaluation shows that the method overcomes several drawbacks reported in previous algorithms, including geometric and image processing attacks such as JPEG and JPEG2000.

PatchR

2015 ◽  
Vol 11 (1) ◽  
pp. 30-45
Author(s):  
Magnus Knuth ◽  
Harald Sack
Keyword(s):  
Missing Data ◽  
Real World ◽  
Linked Data ◽  
Real World Applications ◽  
Change Requests ◽  
Incorrect Data ◽  
The Web

Incorrect or outdated data is a common problem when working with Linked Data in real world applications. Linked Data is distributed over the web and under control of various dataset publishers. It is difficult for data publishers to ensure the quality and timeliness of the data all by themselves, though they might receive individual complaints by data users, who identified incorrect or missing data. Indeed, the authors see Linked Data consumers equally responsible for the quality of the datasets they use. PatchR provides a vocabulary to report incorrect data and to propose changes to correct them. Based on the PatchR ontology a framework is suggested that allows users to efficiently report and data publishers to handle change requests for their datasets.

ECAI-96 workshop on validation, verification and refinement of KBS: A short report

1997 ◽  
Vol 12 (01) ◽  
pp. 95-98 ◽  
Author(s):  
MARIE-CHRISTINE ROUSSET ◽  
SUSAN CRAW
Keyword(s):  
Software Engineering ◽  
Real World ◽  
Short Report ◽  
Knowledge Based Systems ◽  
Critical Factors ◽  
Knowledge Based ◽  
Real World Applications

Ensuring reliability and enhancing quality of Knowledge Based Systems (KBS) are critical factors for their successful deployment in real-world applications. This is a broad task involving both methodological and formal approaches for designing rigorous Validation, Verification and Testing (VVT) methods and tools. Some of these can be adapted from conventional software engineering, while others rely on specific aspects of KBS.

Q-Learning in Continuous State-Action Space with Noisy and Redundant Inputs by Using a Selective Desensitization Neural Network

2015 ◽  
Vol 19 (6) ◽  
pp. 825-832 ◽  
Author(s):  
Takaaki Kobayashi ◽  
◽  
Takeshi Shibuya ◽  
Masahiko Morita
Keyword(s):  
Neural Network ◽  
Real World ◽  
Value Function ◽  
Action Space ◽  
Sensor Noise ◽  
Q Learning ◽  
State Action ◽  
Continuous State ◽  
Real World Applications ◽  
Function Approximator

When applying reinforcement learning (RL) algorithms such as Q-learning to real-world applications, we must consider the influence of sensor noise. The simplest way to reduce such noise influence is to additionally use other types of sensors, but this may require more state space -- and probably increase redundancy. Conventional value-function approximators used to RL in continuous state-action space do not deal appropriately with such situations. The selective desensitization neural network (SDNN) has high generalization ability and robustness against noise and redundant input. We therefore propose an SDNN-based value-function approximator for Q-learning in continuous state-action space, and evaluate its performance in terms of robustness against redundant input and sensor noise. Results show that our proposal is strongly robust against noise and redundant input and enables the agent to take better actions by using additional inputs without degrading learning efficiency. These properties are eminently advantageous in real-world applications such as in robotic systems.

scholarly journals Information accuracy in legislative oversight: Theoretical implications and experimental evidence

2017 ◽  
Vol 29 (2) ◽  
pp. 226-254 ◽  
Author(s):  
Susumu Shikano ◽  
Michael F Stoffel ◽  
Markus Tepe
Keyword(s):  
Decision Making ◽  
Real World ◽  
Important Determinant ◽  
Random Noise ◽  
High Quality ◽  
Specific Cost ◽  
Legislative Oversight ◽  
Real World Applications ◽  
The Relationship

The relationship between legislatures and bureaucracies is typically modeled as a principal–agent game. Legislators can acquire information about the (non-)compliance of bureaucrats at some specific cost. Previous studies consider the information from oversight to be perfect, which contradicts most real-world applications. We therefore provide a model that includes random noise as part of the information. The quality of provided goods usually increases with information accuracy while simultaneously requiring less oversight. However, bureaucrats never provide high quality if information accuracy is below a specific threshold. We assess the empirical validity of our predictions in a lab experiment. Our data show that information accuracy is indeed an important determinant of both legislator and bureaucrat decision-making.

scholarly journals A Clampdown on Service Refusals by Bangkok Taxis

2019 ◽  
Vol 16 (1) ◽  
pp. 38-50
Author(s):  
Kridsda Nimmanunta ◽  
Thunyarat (Bam) Amornpetchkul
Keyword(s):  
Real World ◽  
Real Option ◽  
Social Issues ◽  
Well Being ◽  
Quality Of Services ◽  
Taxi Drivers ◽  
Economic Decisions ◽  
Real World Applications ◽  
Versatile Tool

One of Bangkok’s most perennial problems was the misbehaviour of taxi drivers. In only 4 months, from October 2015 to January 2016, the Department of Land Transport under the Ministry of Transport (MOT) of Thailand received almost 15,000 complaints regarding the quality of services provided by Bangkok’s taxi drivers. The number one complaint was passenger refusal. Anybody taking a taxi, particularly during rush hour, was likely to get frustrated with some taxi drivers, who got flagged down but refused to go to the requested destinations. Several attempts had been made by the MOT to resolve the issue of taxi drivers refusing passengers, including imposing fines and suspending taxi drivers, allowing fare raise to improve taxi drivers’ well-being, hoping to provide higher quality services and to abide by the laws and regulations. So far, the results had been unsatisfactory. This case aims to show the beauty and usefulness of real options in real-world applications by looking at one of Bangkok’s most perennial problems of taxi drivers refusing passengers. A real option is a powerful framework for business, finance and economic decisions. Not only that, but it is also a versatile tool for resolving social issues.

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