9 pages, 725 KiB  
Article
Users’ Reaction Time for Improvement of Security and Access Control in Web Services
by Shamil Magomedov, Alexander Gusev, Dmitry Ilin and Evgeny Nikulchev
Appl. Sci. 2021, 11(6), 2561; https://doi.org/10.3390/app11062561 - 12 Mar 2021
Cited by 5 | Viewed by 2459
Abstract
This paper concerns the case of the development of a technology for increasing the efficiency of access control based on the user behavior monitoring built into a software system’s user interface. It is proposed to use the time of user reactions as individual [...] Read more.
This paper concerns the case of the development of a technology for increasing the efficiency of access control based on the user behavior monitoring built into a software system’s user interface. It is proposed to use the time of user reactions as individual indicators of psychological and psychophysical state. This paper presents the results and interpretation of user reactions collected during a mass web survey of students of the Russian Federation. The total number of users was equal to 22,357. To reveal the patterns in user reactions, both quantitative and qualitative approaches were applied. The analysis of the data demonstrated that the user could be characterized by their psychomotor reactions, collected during the answering of a set of questions. Those reactions reflected the personal skills of the interface interaction, the speed of reading, and the speed of answering. Thus, those observations can be used as a supplement to personal verification in information systems. The collection of the reaction times did not load the data volumes significantly nor transmit confidential information. Full article
(This article belongs to the Special Issue Big Data: Advanced Methods, Interdisciplinary Study and Applications)
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34 pages, 40942 KiB  
Article
Learn-CIAM: A Model-Driven Approach for the Development of Collaborative Learning Tools
by Yoel Arroyo, Ana I. Molina, Miguel A. Redondo and Jesús Gallardo
Appl. Sci. 2021, 11(6), 2554; https://doi.org/10.3390/app11062554 - 12 Mar 2021
Cited by 6 | Viewed by 2541
Abstract
This paper introduces Learn-CIAM, a new model-based methodological approach for the design of flows and for the semi-automatic generation of tools in order to support collaborative learning tasks. The main objective of this work is to help professors by establishing a series of [...] Read more.
This paper introduces Learn-CIAM, a new model-based methodological approach for the design of flows and for the semi-automatic generation of tools in order to support collaborative learning tasks. The main objective of this work is to help professors by establishing a series of steps for the specification of their learning courses and the obtaining of collaborative tools to support certain learning activities (in particular, for in-group editing, searching and modeling). This paper presents a complete methodological framework, how it is supported conceptually and technologically, and an application example. So to guarantee the validity of the proposal, we also present some validation processes with potential designers and users from different profiles such as Education and Computer Science. The results seem to demonstrate a positive reception and acceptance, concluding that its application would facilitate the design of learning courses and the generation of collaborative learning tools for professionals of both profiles. Full article
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25 pages, 1566 KiB  
Article
Experiments with Neural Networks in the Identification and Control of a Magnetic Levitation System Using a Low-Cost Platform
by Bruno E. Silva and Ramiro S. Barbosa
Appl. Sci. 2021, 11(6), 2535; https://doi.org/10.3390/app11062535 - 12 Mar 2021
Cited by 8 | Viewed by 3127
Abstract
In this article, we designed and implemented neural controllers to control a nonlinear and unstable magnetic levitation system composed of an electromagnet and a magnetic disk. The objective was to evaluate the implementation and performance of neural control algorithms in a low-cost hardware. [...] Read more.
In this article, we designed and implemented neural controllers to control a nonlinear and unstable magnetic levitation system composed of an electromagnet and a magnetic disk. The objective was to evaluate the implementation and performance of neural control algorithms in a low-cost hardware. In a first phase, we designed two classical controllers with the objective to provide the training data for the neural controllers. After, we identified several neural models of the levitation system using Nonlinear AutoRegressive eXogenous (NARX)-type neural networks that were used to emulate the forward dynamics of the system. Finally, we designed and implemented three neural control structures: the inverse controller, the internal model controller, and the model reference controller for the control of the levitation system. The neural controllers were tested on a low-cost Arduino control platform through MATLAB/Simulink. The experimental results proved the good performance of the neural controllers. Full article
(This article belongs to the Section Computing and Artificial Intelligence)
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20 pages, 26236 KiB  
Article
An Information Recommendation Technique Based on Influence and Activeness of Users in Social Networks
by Minsoo Lee and Soyeon Oh
Appl. Sci. 2021, 11(6), 2530; https://doi.org/10.3390/app11062530 - 12 Mar 2021
Cited by 6 | Viewed by 2561
Abstract
Over the past few years, the number of users of social network services has been exponentially increasing and it is now a natural source of data that can be used by recommendation systems to provide important services to humans by analyzing applicable data [...] Read more.
Over the past few years, the number of users of social network services has been exponentially increasing and it is now a natural source of data that can be used by recommendation systems to provide important services to humans by analyzing applicable data and providing personalized information to users. In this paper, we propose an information recommendation technique that enables smart recommendations based on two specific types of analysis on user behaviors, such as the user influence and user activity. The components to measure the user influence and user activity are identified. The accuracy of the information recommendation is verified using Yelp data and shows significantly promising results that could create smarter information recommendation systems. Full article
(This article belongs to the Special Issue Advanced Analysis Technologies for Social Media)
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20 pages, 550 KiB  
Article
Citizens’ Perception of Smart Cities: A Case Study
by Athanasios Georgiadis, Panayiotis Christodoulou and Zinon Zinonos
Appl. Sci. 2021, 11(6), 2517; https://doi.org/10.3390/app11062517 - 11 Mar 2021
Cited by 34 | Viewed by 8566
Abstract
The 21st century is considered to be “The Century of Cities”. By the end of this century, over 80% of the global population is expected to be living in urban areas. To become smart, a city should develop an approach of services that [...] Read more.
The 21st century is considered to be “The Century of Cities”. By the end of this century, over 80% of the global population is expected to be living in urban areas. To become smart, a city should develop an approach of services that will focus mainly on citizens to be the primary beneficiaries of the services offered by a Smart City. In this work, we present through a survey of 545 participants, the citizens’ perception about the smart city concept and reveal the Greek and Cypriot citizens’ level of knowledge regards to a Smart City’s actions, applications, and elements. The final results of this study revealed several interesting outcomes. Firstly, this study showed that Cypriot citizens seem to know better what a “Smart City” is compared to Greek citizens, secondly, the study revealed that a large number of participants do not believe that any efforts have been made in their city in order to become “smart” and finally, regards to the most important challenges for the development of a smart city, the survey disclose that the cooperation of the private and public sector is the biggest challenge that needs to be tackled so as citizens can move towards a “smarter” future. Full article
(This article belongs to the Special Issue New Trends in Social Computing and Its Applications)
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17 pages, 1781 KiB  
Article
gbt-HIPS: Explaining the Classifications of Gradient Boosted Tree Ensembles
by Julian Hatwell, Mohamed Medhat Gaber and R. Muhammad Atif Azad
Appl. Sci. 2021, 11(6), 2511; https://doi.org/10.3390/app11062511 - 11 Mar 2021
Cited by 8 | Viewed by 3613
Abstract
This research presents Gradient Boosted Tree High Importance Path Snippets (gbt-HIPS), a novel, heuristic method for explaining gradient boosted tree (GBT) classification models by extracting a single classification rule (CR) from the ensemble of decision trees that make up the GBT model. This [...] Read more.
This research presents Gradient Boosted Tree High Importance Path Snippets (gbt-HIPS), a novel, heuristic method for explaining gradient boosted tree (GBT) classification models by extracting a single classification rule (CR) from the ensemble of decision trees that make up the GBT model. This CR contains the most statistically important boundary values of the input space as antecedent terms. The CR represents a hyper-rectangle of the input space inside which the GBT model is, very reliably, classifying all instances with the same class label as the explanandum instance. In a benchmark test using nine data sets and five competing state-of-the-art methods, gbt-HIPS offered the best trade-off between coverage (0.16–0.75) and precision (0.85–0.98). Unlike competing methods, gbt-HIPS is also demonstrably guarded against under- and over-fitting. A further distinguishing feature of our method is that, unlike much prior work, our explanations also provide counterfactual detail in accordance with widely accepted recommendations for what makes a good explanation. Full article
(This article belongs to the Special Issue Explainable Artificial Intelligence (XAI))
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17 pages, 843 KiB  
Article
Experimental Analysis of Friend-And-Native Based Location Awareness for Accurate Collaborative Filtering
by Aaron Ling Chi Yi and Dae-Ki Kang
Appl. Sci. 2021, 11(6), 2510; https://doi.org/10.3390/app11062510 - 11 Mar 2021
Cited by 3 | Viewed by 2267
Abstract
Location-based recommender systems have gained a lot of attention in both commercial domains and research communities where there are various approaches that have shown great potential for further studies. However, there has been little attention in previous research on location-based recommender systems for [...] Read more.
Location-based recommender systems have gained a lot of attention in both commercial domains and research communities where there are various approaches that have shown great potential for further studies. However, there has been little attention in previous research on location-based recommender systems for generating recommendations considering the locations of target users. Such recommender systems sometimes recommend places that are far from the target user’s current location. In this paper, we explore the issues of generating location recommendations for users who are traveling overseas by taking into account the user’s social influence and also the native or local expert’s knowledge. Accordingly, we have proposed a collaborative filtering recommendation framework called the Friend-And-Native-Aware Approach for Collaborative Filtering (FANA-CF), to generate reasonable location recommendations for users. We have validated our approach by systematic and extensive experiments using real-world datasets collected from Foursquare TM. By comparing algorithms such as the collaborative filtering approach (item-based collaborative filtering and user-based collaborative filtering) and the personalized mean approach, we have shown that our proposed approach has slightly outperformed the conventional collaborative filtering approach and personalized mean approach. Full article
(This article belongs to the Special Issue Applied Artificial Intelligence (AI))
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22 pages, 2355 KiB  
Article
SENIOR: An Intelligent Web-Based Ecosystem to Predict High Blood Pressure Adverse Events Using Biomarkers and Environmental Data
by Sergio López Bernal, Javier Martínez Valverde, Alberto Huertas Celdrán and Gregorio Martínez Pérez
Appl. Sci. 2021, 11(6), 2506; https://doi.org/10.3390/app11062506 - 11 Mar 2021
Cited by 4 | Viewed by 2487
Abstract
Web platforms are gaining relevance in eHealth, where they ease the interaction between patients and clinician. However, some clinical fields, such as the cardiovascular one, still need more effort because cardiovascular diseases are the principal cause of death and medical resources expenditure worldwide. [...] Read more.
Web platforms are gaining relevance in eHealth, where they ease the interaction between patients and clinician. However, some clinical fields, such as the cardiovascular one, still need more effort because cardiovascular diseases are the principal cause of death and medical resources expenditure worldwide. The lack of daily control is the main reason hypertension is a current health problem, and medical web services could improve this situation. To face this challenge, this work proposes a novel intelligent web-based ecosystem, called SENIOR, capable of predicting adverse blood pressure events. The innovation of the SENIOR ecosystem relies on a wearable device measuring patient’s biomarkers such as blood pressure, a mobile application acquiring patient’s information, and a web platform consulting environmental services, processing data, and predicting blood pressure. The second contribution of this work is to consider novel environmental features based on the users’ location, such as climate and pollution data, to increase the knowledge about known variables affecting hypertension. Finally, our last contribution is a proof of concept with several machine learning algorithms predicting blood pressure values both in real-time and future temporal windows within one day has demonstrated the suitability of SENIOR. Full article
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18 pages, 1816 KiB  
Article
Improvement of Tourists Satisfaction According to Their Non-Verbal Preferences Using Computational Intelligence
by Claudia C. Tusell-Rey, Ricardo Tejeida-Padilla, Oscar Camacho-Nieto, Yenny Villuendas-Rey and Cornelio Yáñez-Márquez
Appl. Sci. 2021, 11(6), 2491; https://doi.org/10.3390/app11062491 - 11 Mar 2021
Cited by 5 | Viewed by 3722
Abstract
In the tourism industry it is common that the information obtained from customers can be varied, dispersed, and with high volumes of data. In this context, the automatic analysis of information has been proposed through electronic customer relationship management, which refers to marketing [...] Read more.
In the tourism industry it is common that the information obtained from customers can be varied, dispersed, and with high volumes of data. In this context, the automatic analysis of information has been proposed through electronic customer relationship management, which refers to marketing activities, tools and techniques, delivered with the use of electronic channels for the specific purpose of locating, building and improving long- term relationships with customers, to enhance their individual potential. In this paper, we refer to the analysis of information in three aspects: customer satisfaction, the study of customer behavior and the forecast of tourist demand. Specifically, we have created a novel dataset comprising the non-verbal preference assessment of tourists who are clients of the Sol Cayo Guillermo hotel belonging to the Melia hotel chain, in Jardines del Rey, Cuba. Then, by applying Computational Intelligence algorithms to this dataset, we achieve segment customers according to their non-verbal preferences, in order to increase their satisfaction, and therefore the client profitability. In order to achieve a good performance in the realization of this task, we have proposed two modifications of the Naïve Associative Classifier, whose results are compared with the most relevant computational algorithms of the state of the art. The experimentally obtained values of balanced accuracy and averaged F1 measure show that, by clearly improving the results of the state-of-the-art algorithms, our proposal is adequate to successfully use electronic customer relationship management in the tourist services provided by hotel chains. Full article
(This article belongs to the Special Issue Applications of Emerging Digital Technologies: Beyond AI & IoT)
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14 pages, 1539 KiB  
Article
Capsule Network Improved Multi-Head Attention for Word Sense Disambiguation
by Jinfeng Cheng, Weiqin Tong and Weian Yan
Appl. Sci. 2021, 11(6), 2488; https://doi.org/10.3390/app11062488 - 10 Mar 2021
Cited by 3 | Viewed by 2198
Abstract
Word sense disambiguation (WSD) is one of the core problems in natural language processing (NLP), which is to map an ambiguous word to its correct meaning in a specific context. There has been a lively interest in incorporating sense definition (gloss) into neural [...] Read more.
Word sense disambiguation (WSD) is one of the core problems in natural language processing (NLP), which is to map an ambiguous word to its correct meaning in a specific context. There has been a lively interest in incorporating sense definition (gloss) into neural networks in recent studies, which makes great contribution to improving the performance of WSD. However, disambiguating polysemes of rare senses is still hard. In this paper, while taking gloss into consideration, we further improve the performance of the WSD system from the perspective of semantic representation. We encode the context and sense glosses of the target polysemy independently using encoders with the same structure. To obtain a better presentation in each encoder, we leverage the capsule network to capture different important information contained in multi-head attention. We finally choose the gloss representation closest to the context representation of the target word as its correct sense. We do experiments on English all-words WSD task. Experimental results show that our method achieves good performance, especially having an inspiring effect on disambiguating words of rare senses. Full article
(This article belongs to the Section Computing and Artificial Intelligence)
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16 pages, 8210 KiB  
Article
A Speech Command Control-Based Recognition System for Dysarthric Patients Based on Deep Learning Technology
by Yu-Yi Lin, Wei-Zhong Zheng, Wei Chung Chu, Ji-Yan Han, Ying-Hsiu Hung, Guan-Min Ho, Chia-Yuan Chang and Ying-Hui Lai
Appl. Sci. 2021, 11(6), 2477; https://doi.org/10.3390/app11062477 - 10 Mar 2021
Cited by 29 | Viewed by 4619
Abstract
Voice control is an important way of controlling mobile devices; however, using it remains a challenge for dysarthric patients. Currently, there are many approaches, such as automatic speech recognition (ASR) systems, being used to help dysarthric patients control mobile devices. However, the large [...] Read more.
Voice control is an important way of controlling mobile devices; however, using it remains a challenge for dysarthric patients. Currently, there are many approaches, such as automatic speech recognition (ASR) systems, being used to help dysarthric patients control mobile devices. However, the large computation power requirement for the ASR system increases implementation costs. To alleviate this problem, this study proposed a convolution neural network (CNN) with a phonetic posteriorgram (PPG) speech feature system to recognize speech commands, called CNN–PPG; meanwhile, the CNN model with Mel-frequency cepstral coefficient (CNN–MFCC model) and ASR-based systems were used for comparison. The experiment results show that the CNN–PPG system provided 93.49% accuracy, better than the CNN–MFCC (65.67%) and ASR-based systems (89.59%). Additionally, the CNN–PPG used a smaller model size comprising only 54% parameter numbers compared with the ASR-based system; hence, the proposed system could reduce implementation costs for users. These findings suggest that the CNN–PPG system could augment a communication device to help dysarthric patients control the mobile device via speech commands in the future. Full article
(This article belongs to the Special Issue Machine Learning and Signal Processing for IOT Applications)
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14 pages, 9074 KiB  
Article
Genetic Optimization of a Manipulator: Comparison between Straight, Rounded, and Curved Mechanism Links
by Robert Pastor, Zdenko Bobovský, Daniel Huczala and Stefan Grushko
Appl. Sci. 2021, 11(6), 2471; https://doi.org/10.3390/app11062471 - 10 Mar 2021
Cited by 10 | Viewed by 2668
Abstract
There are several ubiquitous kinematic structures that are used in industrial robots, with the most prominent being a six-axis angular structure. However, researchers are experimenting with task-based mechanism synthesis that could provide higher efficiency with custom optimized manipulators. Many studies have focused on [...] Read more.
There are several ubiquitous kinematic structures that are used in industrial robots, with the most prominent being a six-axis angular structure. However, researchers are experimenting with task-based mechanism synthesis that could provide higher efficiency with custom optimized manipulators. Many studies have focused on finding the most efficient optimization algorithm for task-based robot manipulators. These manipulators, however, are usually optimized from simple modular joints and links, without exploring more elaborate modules. Here, we show that link modules defined by small numbers of parameters have better performance than more complicated ones. We compare four different manipulator link types, namely basic predefined links with fixed dimensions, straight links that can be optimized for different lengths, rounded links, and links with a curvature defined by a Hermite spline. Manipulators are then built from these modules using a genetic algorithm and are optimized for three different tasks. The results demonstrate that manipulators built from simple links not only converge faster, which is expected given the fewer optimized parameters, but also converge on lower cost values. Full article
(This article belongs to the Special Issue Intelligent Robotics)
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10 pages, 1721 KiB  
Article
Bayesian Model Infers Drug Repurposing Candidates for Treatment of COVID-19
by Michael A. Kiebish, Punit Shah, Rangaprasad Sarangarajan, Vivek K. Vishnudas, Stephane Gesta, Poornima K. Tekumalla, Chas Bountra, Elder Granger, Eric Schadt, Leonardo O. Rodrigues and Niven R. Narain
Appl. Sci. 2021, 11(6), 2466; https://doi.org/10.3390/app11062466 - 10 Mar 2021
Cited by 3 | Viewed by 3019
Abstract
The emergence of COVID-19 progressed into a global pandemic that has functionally put the world at a standstill and catapulted major healthcare systems into an overburdened state. The dire need for therapeutic strategies to mitigate and successfully treat COVID-19 is now a public [...] Read more.
The emergence of COVID-19 progressed into a global pandemic that has functionally put the world at a standstill and catapulted major healthcare systems into an overburdened state. The dire need for therapeutic strategies to mitigate and successfully treat COVID-19 is now a public health crisis with national security implications for many countries. The current study employed Bayesian networks to a longitudinal proteomic dataset generated from Caco-2 cells transfected with SARS-CoV-2 (isolated from patients returning from Wuhan to Frankfurt). Two different approaches were employed to assess the Bayesian models, a titer-center topology analysis and a drug signature enrichment analysis. Topology analysis identified a set of proteins directly linked to the SAR-CoV2 titer, including ACE2, a SARS-CoV-2 binding receptor, MAOB and CHECK1. Aligning with the topology analysis, MAOB and CHECK1 were also identified within the enriched drug-signatures. Taken together, the data output from this network has identified nodal host proteins that may be connected to 18 chemical compounds, some already marketed, which provides an immediate opportunity to rapidly triage these assets for safety and efficacy against COVID-19. Full article
(This article belongs to the Special Issue Applications of Artificial Intelligence in Pharmaceutics)
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