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Instituto de Telecomunicações, Portugal

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12 Papers

Performance Analysis of PAM4 Signal Transmission in Inter-datacenter Multicore Fiber Links Impaired by Inter-Core Crosstalk

Topic: Optical Communications and Networking

Authors: Rafael Dias ¹ , João Rebola ^{1

;

2} and Adolfo Cartaxo ^{1

;

2}

Affiliations: ¹ Instituto Universitário de Lisboa (ISCTE-IUL), Lisboa, Portugal , ² Optical Communications and Photonics Group, Instituto de Telecomunicações, Lisboa, Portugal

Digital Object Identifier: 10.5220/0010321000940103

Proceedings of PHOTOPTICS 2021, ISBN: 978-989-758-492-3

Quick Abstract

In this work, we propose to use four-level pulse amplitude modulation (PAM4) and multicore fibers (MCFs) to support very high capacity inter-datacenter connections. The limitations imposed by inter-core crosstalk (ICXT) on the performance of 112 Gb/s up to 80 km-long optically amplified PAM4 inter-datacenter links with intensity-modulation and direct-detection (IM-DD) and full chromatic dispersion compensation in the optical domain are analyzed through numerical simulation. We show that those PAM4 inter-datacenter links achieve an outage probability (OP) of 10−4 with a maximum ICXT level of -13.9 dB for high skew-symbol rate products and require an ICXT level decrease of about 8.1 dB to achieve the same OP for low skew-symbol rate products. Due to using full dispersion compensation, the OP is not much affected by increasing the MCF length, from 10 km, where electrical noise significantly contributes to the performance degradation, to 80 km, where signal-amplified spontaneous emission beat noise is dominant. For an OP of 10−4, the maximum acceptable ICXT level shows only a 1.4 dB variation with the MCF length increase.

Multi-factor Authentication for Improved Efficiency in ECG: Based Login

Topics: Biomedical Devices for Computer Interaction; Biosignal Acquisition, Analysis and Processing; Processing of Multimodal Input; Physiology-Driven Computer Interaction

Authors: Pedro Neves ¹ , Luís Nunes ¹ and André Lourenço ²

Affiliations: ¹ Instituto Universitário de Lisboa (ISCTE) and Instituto de Telecomunicações, Portugal , ² Instituto Superior de Engenharia de Lisboa (ISEL) and Instituto de Telecomunicações, Portugal

Digital Object Identifier: 10.5220/0005936500670074

Proceedings of PhyCS 2016, ISBN: 978-989-758-197-7

Quick Abstract

Electrocardiogram (ECG) based biometrics have proven to be a reliable source of identification. ECG can now be measured off-the-person, requiring nothing more than dry electrodes or conductive fabrics to acquire a usable ECG signal. However, identification still has a relatively poor performance when using large user databases. In this paper we suggest using ECG authentication associated with a smartphone security token in order to improve performance and decrease the time required for the recognition. This paper reposts the implementation of this technique in a user authentication scenario for a Windows login using normal Bluetooth (BT) and Bluetooth Low Energy (BLE). This paper also uses Intel Edison’s mobility features to create a more versatile environment. Results proved our solution to be feasible and present improvements in authentication times when compared to a simple ECG identification.

Related Ontology Subjects/Areas/Topics (11)

Applications	Human-Computer Interaction	Physiology-Driven Computer Interaction
Biomedical Devices for Computer Interaction	Methodologies and Methods	Processing of Multimodal Input
Biosignal Acquisition, Analysis and Processing	Pattern Recognition	Software Engineering
Devices	Physiological Computing Systems

Design of Communication and Control for Swarms of Aquatic Surface Drones

Topics: Multi-Agent Systems; Evolutionary Computing; Cooperation and Coordination; Autonomous Systems; Collective Intelligence; Physical Agents; Robot and Multi-Robot Systems; Self Organizing Systems

Authors: Anders Lyhne Christensen ¹ , Sancho Oliveira ¹ , Octavian Postolache ² , Maria João de Oliveira ³ , Susana Sargento ⁴ , Pedro Santana ² , Luis Nunes ² , Fernando Velez ⁵ , Pedro Sebastião ² , Vasco Costa ¹ , Miguel Duarte ¹ , Jorge Gomes ⁶ , Tiago Rodrigues ¹ and Fernando Silva ⁶

Affiliations: ¹ Instituto de Telecomunicações, Instituto Universitário de Lisboa (ISCTE-IUL) and BioMachines Lab, Portugal , ² Instituto de Telecomunicações and Instituto Universitário de Lisboa (ISCTE-IUL), Portugal , ³ Instituto Universitário de Lisboa (ISCTE-IUL) and Vitruvius FabLab-IUL, Portugal , ⁴ Instituto de Telecomunicações and Universidade de Aveiro, Portugal , ⁵ Instituto de Telecomunicações and Universidade da Beira Interior, Portugal , ⁶ Instituto de Telecomunicações, BioMachines Lab, LabMAg and Faculdade de Ciencias da Universidade de Lisboa, Portugal

Digital Object Identifier: 10.5220/0005281705480555

Proceedings of ICAART 2015, ISBN: 978-989-758-074-1

Quick Abstract

The availability of relatively capable and inexpensive hardware components has made it feasible to consider large-scale systems of autonomous aquatic drones for maritime tasks. In this paper, we present the CORATAM and HANCAD projects, which focus on the fundamental challenges related to communication and control in swarms of aquatic drones. We argue for: (i) the adoption of a heterogeneous approach to communication in which a small subset of the drones have long-range communication capabilities while the majority carry only short-range communication hardware, and (ii) the use of decentralized control to facilitate inherent robustness and scalability. A heterogeneous communication system and decentralized control allow for the average drone to be kept relatively simple and therefore inexpensive. To assess the proposed methodology, we are currently building 25 prototype drones from off-the-shelf components. We present the current hardware designs and discuss the results of simulation-based experiments involving swarms of up to 1,000 aquatic drones that successfully patrolled a 20 km-long strip for 24 hours.

Related Ontology Subjects/Areas/Topics (19)

Agents	Distributed and Mobile Software Systems	Physical Agents
Artificial Intelligence	Enterprise Information Systems	Robot and Multi-Robot Systems
Artificial Intelligence and Decision Support Systems	Evolutionary Computing	Self Organizing Systems
Autonomous Systems	Knowledge Engineering and Ontology Development	Soft Computing
Collective Intelligence	Knowledge-Based Systems	Software Engineering
Computational Intelligence	Multi-Agent Systems	Symbolic Systems
Cooperation and Coordination

Human Activity Recognition and Prediction

Authors: David Jardim ¹ , Luis Nunes ² and Miguel Sales Dias ³

Affiliations: ¹ Microsoft Language and Development Center and Instituto Universitário de Lisboa (ISCTE-IUL), Portugal , ² Instituto Universitário de Lisboa (ISCTE-IUL) and IT - Instituto de Telecomunicações, Portugal , ³ Microsoft Language and Development Center, Instituto Universitário de Lisboa (ISCTE-IUL) and ISTAR-IUL, Portugal

Proceedings of DCPRAM 2015/ICPRAM

Quick Abstract

Human activity recognition (HAR) has become one of the most active research topics in image processing and pattern recognition. Detecting specific activities in a live feed or searching in video archives still relies almost completely on human resources. Detecting multiple activities in real-time video feeds is currently performed by assigning multiple analysts to simultaneously watch the same video stream. Manual analysis of video is labour intensive, fatiguing, and error prone. Solving the problem of recognizing human activities from video can lead to improvements in several applications fields like in surveillance systems, human computer interfaces, sports video analysis, digital shopping assistants, video retrieval, gaming and health-care. This area has grown dramatically in the past 10 years, and throughout our research we identified a potentially underexplored sub-area: Action Prediction. What if we could infer the future actions of people from visual input? We propose to expand the current vision-based activity analysis to a level where it is possible to predict the future actions executed by a subject. We are interested in interactions which can involve a single actor, two humans and/or simple objects. For example try to predict if “a person will cross the street” or “a person will try to steal a hand-bag from another” or were will a tenis-player target the next voley. Using a hierarchical approach we intend to represent high-level human activities that are composed of other simpler activities, which are usually called sub-events which may themselves be decomposable. We expect to develop a system capable of predicting the next action in a sequence initially using offline-learning and then with self-improvement/task specialization in mind, using online-learning.

A Data-driven Approach to Predict Hospital Length of Stay - A Portuguese Case Study

Topics: Applications of Expert Systems; Data Mining

Authors: Nuno Caetano ¹ , Raul M. S. Laureano ¹ and Paulo Cortez ²

Affiliations: ¹ Instituto Universitário de Lisboa (ISCTE-IUL), Portugal , ² University of Minho, Portugal

Digital Object Identifier: 10.5220/0004892204070414

Proceedings of ICEIS 2014, ISBN: 978-989-758-027-7

Quick Abstract

Data Mining (DM) aims at the extraction of useful knowledge from raw data. In the last decades, hospitals have collected large amounts of data through new methods of electronic data storage, thus increasing the potential value of DM in this domain area, in what is known as medical data mining. This work focuses on the case study of a Portuguese hospital, based on recent and large dataset that was collected from 2000 to 2013. A data-driven predictive model was obtained for the length of stay (LOS), using as inputs indicators commonly available at the hospitalization process. Based on a regression approach, several state-of-the-art DM models were compared. The best result was obtained by a Random Forest (RF), which presents a high quality coefﬁcient of determination value (0.81). Moreover, a sensitivity analysis approach was used to extract human understandable knowledge from the RF model, revealing top three inﬂuential input attributes: hospital episode type, the physical service where the patient is hospitalized and the associated medical specialty. Such predictive and explanatory knowledge is valuable for supporting decisions of hospital managers.

Related Ontology Subjects/Areas/Topics (9)

Applications of Expert Systems	Data Mining	Sensor Networks
Artificial Intelligence	Databases and Information Systems Integration	Signal Processing
Artificial Intelligence and Decision Support Systems	Enterprise Information Systems	Soft Computing

Impact of Multi-Rate and Multi-Format Crosstalk Signals on the Performance of 40 Gbit/s DQPSK Optical Receivers

Topics: Fiber Optics; Optical Communications and Networking

Authors: João L. Rebola ¹ , Luis G. C. Cancela ¹ and João J. O. Pires ²

Affiliations: ¹ Instituto de Telecomunicações and Instituto Universitário de Lisboa (ISCTE-IUL), Portugal , ² Instituto de Telecomunicações and Instituto Superior Técnico, Portugal

Digital Object Identifier: 10.5220/0004700900560062

Proceedings of PHOTOPTICS 2014, ISBN: 978-989-758-008-6

Quick Abstract

The coexistence of signals with different modulation formats and different bit rates in metropolitan optical networks is, nowadays, a reality. In-band crosstalk can be very detrimental to the performance of those networks. In this work, the impact of in-band crosstalk due to multi-format and multi-rate signals on the performance of 40 Gbit/s DQPSK optical receivers is evaluated. It is shown that the worst interferer is the 10 Gbit/s OOK signal, which is the most common modulation format in today’s optical networks.

Related Ontology Subjects/Areas/Topics (4)

Fiber Optics		Optics		Photonics, Optics and Laser Technology
Optical Communications and Networking

From 7 to 77 - I Teach You and You Teach Me!

Topics: Intelligent User Interfaces; AI and Creativity

Authors: Tiago Amaral and Isabel Machado Alexandre

Affiliation: Instituto de Telecomunicações & Instituto Universitário de Lisboa (ISCTE-IUL), Portugal

Digital Object Identifier: 10.5220/0004333605870591

Proceedings of ICAART 2013, ISBN: 978-989-8565-39-6

Quick Abstract

This paper presents a project that aims to devise an innovative interactive application, more precisely a serious game, covering the topic of financial education. The topic is quite relevant nowadays, not only in Europe but worldwide, and is also one of the major issues on most government’s agendas. The aim of this application is by using a storytelling framework devise a collaborative platform, where people from 7 to 77 acquire or enhance their financial skills. To do this, the application tackles several research fields such as interactive digital storytelling, collaboration human-computer interaction, autonomous agents, etc.

Related Ontology Subjects/Areas/Topics (6)

AI and Creativity		Enterprise Information Systems		Intelligent User Interfaces
Artificial Intelligence		Human-Computer Interaction		Soft Computing

Factors Influencing Information Sharing in Four SME Networks in Portugal - A Coordination Perspective

Topics: Communication, Collaboration and Information Sharing; Learning Organization & Organizational Learning

Authors: Esther Lage and Bráulio Alturas

Affiliation: Instituto Universitário de Lisboa (ISCTE-IUL), Portugal

Digital Object Identifier: 10.5220/0004135401780183

Proceedings of KMIS 2012/IC3K, ISBN: 978-989-8565-31-0

Quick Abstract

Sharing a minimum amount of information is a basic condition for working in cooperation. The aim of this study was to identify aspects that influence information sharing within inter-organizational networks through an exploratory and qualitative approach. The coordination’s representatives of four networks were interviewed: the Majority-Partner of a Purchase Network (RAVT), the Technical Consultant of an Innovation Network (COTEC), the General Secretary of a cluster representation network (CEFAMOL) and the President of a Network of Associations (UACS). Aspects related to the information sharing were identified, such as information quality, top management commitment, trust, network coordination’s role, reciprocity and age. Further researches can deepen these results by comparing them with network companies’ view.

Related Ontology Subjects/Areas/Topics (6)

Artificial Intelligence		Knowledge Management and Information Sharing		Learning Organization & Organizational Learning
Communication, Collaboration and Information Sharing		Knowledge-Based Systems		Symbolic Systems

HAND IN HAND - Maths and Storytelling together in an Educational Game

Topics: Intelligent User Interfaces; Multi-Agent Systems; Conversational Agents

Authors: Isabel Machado Alexandre ¹ , David Jardim ² and Pedro Faria Lopes ²

Affiliations: ¹ Instituto de Telecomunicações & Instituto Universitário de Lisboa (ISCTE-IUL), Portugal , ² Instituto Universitário de Lisboa (ISCTE-IUL) & ADETTI-IUL, Portugal

Digital Object Identifier: 10.5220/0003744303350338

Proceedings of ICAART 2012, ISBN: 978-989-8425-96-6

Quick Abstract

In this paper, we describe a novel approach to teaching early mathematical concepts to young children. The approach aims to merge storytelling and Maths. Evidence show that through dramatic games and role-playing activities young children (aging from 5-7 years old) learn to master new knowledge, to fit in a new school setting and to socially relate with their peers. So taking this evidence into account, it is possible to devise an innovative learning scenario that teaches early mathematical concepts by telling and creating stories. To explore this idea, we first started by developing an application that provides children from 5 to 7 years old to learn simple maths concepts by interacting and playing in a game. Then, we take this project a step forward and explore the introduction of storytelling by devising an engaging approach of presenting the maths concepts through the use of a story.

Related Ontology Subjects/Areas/Topics (13)

Agents	Enterprise Information Systems	Knowledge-Based Systems
Artificial Intelligence	Human-Computer Interaction	Multi-Agent Systems
Artificial Intelligence and Decision Support Systems	Intelligent User Interfaces	Software Engineering
Conversational Agents	Knowledge Engineering and Ontology Development	Symbolic Systems
Distributed and Mobile Software Systems

Information and Knowledge Sharing in Inter-organizational Relationships under the Process Approach

Topics: Communication, Collaboration and Information Sharing; Learning Organization & Organizational Learning

Authors: Esther Lage and Bráulio Alturas

Affiliation: Instituto Universitário de Lisboa (ISCTE-IUL), Portugal

Digital Object Identifier: 10.5220/0004139202730276

Proceedings of KMIS 2012/IC3K, ISBN: 978-989-8565-31-0

Quick Abstract

This papers aims to contribute to the understanding of inter-organizational information and knowledge sharing by analyzing how the phenomenon is presented in the literature under the process approach. As results, it was possible to identify how the authors have labeled and measured the phenomenon, the contexts in which it has been investigated and what antecedents have been identified. Aspects that demand further studies were also highlighted. For networks and organizations the study provides lessons regarding the information and knowledge characteristics, firm’s characteristics and channels used to share information and knowledge.

Related Ontology Subjects/Areas/Topics (6)

Artificial Intelligence		Knowledge Management and Information Sharing		Learning Organization & Organizational Learning
Communication, Collaboration and Information Sharing		Knowledge-Based Systems		Symbolic Systems