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This book constitutes the refereed proceedings of the 6th IFIP WG 5.5/SOCOLNET Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2015, held in Costa de Caparica, Portugal, in April 2015. The 54 revised full papers were carefully reviewed and selected from 119 submissions. The papers present selected results produced in engineering doctoral programs and focus on development and application of cloud-based engineering systems. Research results and ongoing work are presented, illustrated and discussed in the following areas: collaborative networks; cloud-based manufacturing; reconfigurable manufacturing; distributed computing and embedded systems; perception and signal processing; healthcare; smart monitoring systems; and renewable energy and energy-related management, decision support, simulation and power conversion.



Erratum to: Selection of Large-Scale 3D Point Cloud Data Using Gesture Recognition

Robin Burgess, António J. Falcão, Tiago Fernandes, Rita A. Ribeiro, Miguel Gomes, Alberto Krone-Martins, André Moitinho de Almeida



Towards Cloud-Based Engineering Systems

Cloud-based Engineering Systems offer new possibilities to leverage the emerging “network effect”, by relying on the access to large pools of computational resources that are available in the “cloud” to overcome the limitations of environments with scarce processing and information storage capability. The impact of this approach is already observed in most engineering domains. Motivating engineering doctoral students to look into the potential of this novel research area is essential for their education. With this aim, the doctoral conference DoCEIS’15 focused on technological innovation for Cloud-based Engineering Systems, challenging the contributors to analyze in which ways their technical and scientific work could contribute to or benefit from this paradigm. The results of this initiative are briefly analyzed in this chapter.

João Martins, Luis M. Camarinha-Matos, João Goes, Luis Gomes

Collaborative Networks


Dealing with the Alignment of Strategies Within the Collaborative Networked Partners

Over the last years, enterprises awareness towards establishing collaborative processes has significantly grown due to the benefits obtained when participating in a collaborative network (CN). This paper is a continuation of the work developed by Andres and Poler [1] in which a set of collaborative processes are identified. This paper particularly focuses on the

strategies alignment (SA) process

, highlighting its influence on the success of a CN. A preliminary framework is outlined to address the collaborative process of SA, consisting of a model, a method and a methodology. Highlighting the importance of the use of cloud-based systems to support small and medium enterprises (SMEs) to deal with the SA process. The implementation of the proposed framework allows identifying what are the strategies that are aligned and how its activation increases the network performance, resulting in more stable and sustainable collaborative relationships, and assuring the proper operation of the CNs.

Beatriz Andres, Raul Poler

The Need of Performance Indicators for Collaborative Business Ecosystems

During last decades there has been a trend to build collaboration platforms as enablers for groups of enterprises to jointly provide integrated services and products. As a result, the notion of business ecosystem is getting wider acceptance. However, a critical issue that is still open, despite some efforts in this area, is the identification of adequate performance indicators to measure and motivate sustainable collaboration. This work-in-progress addresses this concern, briefly presenting the state of the art of relevant contributing areas such as, collaborative networks, business ecosystems, enterprise performance indicators, social networks analysis, and supply chains. Complementarily, through an assessment of current gaps, the research challenges are identified and an approach for further development is proposed.

Paula Graça, Luis M. Camarinha-Matos

Negotiation Environment and Protocols for Collaborative Service Design

During the last decade, in manufacturing and service industries, collaboration among small and medium enterprises (SMEs) has focused on competencies and resources sharing as an approach to both create new competitive environments, as well as to achieve agility to rapidly respond to new market demands. Also, with the increasing level of customization of products and services required by customers, the notion of co-creation of products and business services leads to an increase of collaboration with customers and local suppliers. In this context, this paper presents an approach based on a negotiation support environment that structures the design of new business services under a collaborative perspective. The adopted protocol to facilitate interaction among the multi-users in the negotiation dialog is described.

Ana Inês Oliveira, Luis M. Camarinha-Matos

An Emotional Support System for Collaborative Networks

A particular challenge in the management of collaborative networks is the effective handling of the interactions among participants, especially in what concerns the management of “soft” issues that are not currently available in the execution processes of such networks. These issues can include inter- and intra-organizational abilities, problems in keeping team cohesion, leadership, among others. Moreover, one cannot forget that organizations are composed of people, and people have intrinsically associated emotions which are present in all interactions. In this sense, when not properly handled, some participant’s emotions might put in jeopardy the quality of the collaboration. On the other hand the collective emotional state of the collaborative network can also affect each participant’s emotions. As a contribution to keep the emotional equilibrium of the network, this paper presents the design of an emotional support system, including the identification and categorization of the most influencing positive and negative collective emotions and also the specification and prototyping of the sub-system services.

Filipa Ferrada, Luis M. Camarinha-Matos

Trust-Based Access Control in Storage Middleware Grids: A Reference Framework Proposal to Deploy in the Financial Sector

Fostered by the development of the Web, the financial sector has been able to develop a broad set of shared IT services. Despite the high levels of maturity that have been achieved there are still improvement opportunities concerning the sharing of services by financial institutions. This research addresses the sharing of data storage resources among different financial organizations to fulfil the needs for unplanned peaks of data storage, or to help shortening the time needed to start projects requiring allocation of storage space when this is not available in the organization. To answer to these requirements it was proposed a data grid infrastructure (SRM), centrally managed by a versatile storage resource manager middleware. Senior IT infrastructure managers of representative financial organizations have been questioned to assess the proposed solution. Security has been identified as a key concern that prevents the dissemination of this type of solutions. These solutions may be fostered by the adoption of a security mechanism that would consider the behaviour of the distinct organizations in the use of the shared resources. To meet this requirement the research proposes an algorithm for controlling the access to the storage resources based on trust, where the level of trust in the joint organizations will vary dynamically according to the fulfilment of the rules concerning the use of the shared storage by its users.

Francisco Nunes, Henrique O’Neill

Cloud-Based Manufacturing


Service Composition in the Cloud-Based Manufacturing Focused on the Industry 4.0

The emerging Industry 4.0 concept, also called fourth industrial revolution and understood as smart factory, is based on integration of both Internet of Things and Cyber-Physical Systems. In smart factory, these two concepts are converging to the Internet of Services, which uses the cloud-based manufacturing for creating, publishing, and sharing the services that represent manufacturing processes, and could be offered by virtual enterprises. Therefore, any dispersed partner can meets the market demands according to their skills, capacities, and availability. This paper presents a survey about service composition in a cloud-based manufacturing over the Industry 4.0. To achieve it, the concepts and characteristics about the service composition based on cloud-manufacturing over the Industry 4.0 are presented, and then the advanced researches about it are summarized. After it, the main research challenges over these issues are shown. Finally, discussions on service composition are reported to contribute for the future researches.

Marcos A. Pisching, Fabrício Junqueira, Diolino J. Santos Filho, Paulo E. Miyagi

Cloud-Based Framework for Practical Model-Checking of Industrial Automation Applications

In this paper we address practical aspects of applying the model-checking method for industrial automation systems verification. Several measures are proposed to cope with the high computational complexity of model-checking. To improve scalability of the method, cloud-based verification tools infrastructure is used. Besides, closed-loop plant controller modelling and synchronization of transitions in the SMV (input language for symbolic model checking) model aim at complexity reduction. The state explosion problem is additionally dealt with by using an abstraction of the model of the plant with net-condition event systems, which is then translated to SMV. In addition, bounded model-checking is applied, which helps to achieve results in cases when the state space is too high. The paper concludes with comparison of performance for different complexity reduction methods.

Sandeep Patil, Dmitrii Drozdov, Victor Dubinin, Valeriy Vyatkin

A Cloud-Based Infrastructure to Support Manufacturing Resources Composition

Current development in emerging technologies, such as the Internet of Things (IoT), service-oriented and high-performance computing combined with the increasing advancement of manufacturing technologies and information systems, triggered a new manufacturing model. Modern industrial automation domain is characterized by heterogeneous equipment encompassing distinct functions, network interfaces and I/O specifications and controlled by distinct software/hardware platforms. To cope with such specificity, manufacturing enterprises are demanding for new service-oriented models that aimoc to abstract physical systems in terms of their functionalities/capabilities. In this scenario, Cloud Manufacturing (CMfg) arises as a new networked, service-oriented, customer centric and demand driven paradigm where manufacturing resources and capabilities are virtualized as services available in the cloud to users.

Giovanni Di Orio, Diogo Barata, André Rocha, José Barata

Reconfigurable Manufacturing


Modeling of Mechanisms for Reconfigurable and Distributed Manufacturing Control System

This paper presents the modeling of fault diagnosis mechanisms extending a method to design reconfigurable and distributed manufacturing control system. The method combines different techniques: service-oriented architecture, holonic and multi-agent system, production flow schema and input-output place-transition Petri net. An application example demonstrates advantages of the proposal, such as at cloud-based engineering, reuse, implementation and reconfiguration flexibility.

Robson Marinho da Silva, Edson H. Watanabe, Maurício F. Blos, Fabrício Junqueira, Diolino J. Santos Filho, Paulo E. Miyagi

PRIME as a Generic Agent Based Framework to Support Pluggability and Reconfigurability Using Different Technologies

Presently the manufacturers are facing a challenging and important period. The markets are very different comparatively to the past, with constant changes and facing a big crisis. Hence, with these new characteristics is very important for the companies quick adaptations in order to take advantage of new business opportunities. However on the shop floor is not easy reconfigure the production lines to perform new tasks. The PRIME framework presents an agent based solution capable to rapidly reconfigure and readapt the production line using standard technology. In this paper is demonstrated the usability of this framework with three completely different technologies. With this flexibility, using PRIME it is possible perform plug and produce, reconfigurability and monitoring for all kind of technologies, not obligating the companies to reform all components in the line, avoiding external costs and stoppages.

André Dionísio Rocha, Diogo Barata, Giovanni Di Orio, Tiago Santos, José Barata

The Migration from Conventional Manufacturing Systems for Multi-Agent Paradigm: the First Step

The consumer market ever more calls for diversified products in small batches and the industry lacks production systems that meet the demands with efficiency and ability to adapt quickly. Integrated manufacturing systems implemented have their management for programmable logic controllers and electrical interconnections, control logic and satisfactory robustness, but they do not attend the needs of diversity and flexibility in production. The solutions to these needs refer the company to migrate to the use of new technologies of control, circuit and logic. But, for an industry migrates is a very big and expensive step. Then, there is an urgent need for methods that implement the interface between logic controllers and multi-agent systems in order to evolve an integrated manufacturing system taking advantage of all electrical circuitry, control logic and the logic controller that installs itself, taking advantage of the self-adapting characteristics that the multi-agent systems provide.

João Alvarez Peixoto, José Antonio Barata Oliveira, André Dionísio Rocha, Carlos Eduardo Pereira

Distributed Computing


Experimental Assessment of Cloud Software Dependability Using Fault Injection

In modern cloud software systems, the complexity arising from feature interaction, geographical distribution, security and configurability requirements increases the likelihood of faults. Additional influencing factors are the impact of different execution environments as well as human operation or configuration errors. Assuming that any non-trivial cloud software system contains faults,

robustness testing

is needed to ensure that such faults are discovered as early as possible, and that the overall service is resilient and fault tolerant. To this end,

fault injection

is a means for disrupting the software in ways that uncover bugs and test the fault tolerance mechanisms. In this paper, we discuss how to experimentally assess software dependability in two steps. First, a model of the software is constructed from different runtime observations and configuration information. Second, this model is used to orchestrate fault injection experiments with the running software system in order to quantify dependability attributes such as service availability. We propose the architecture of a fault injection service within the OpenStack project.

Lena Herscheid, Daniel Richter, Andreas Polze

Usability of Scientific Workflow in Dynamically Changing Environment

Scientific workflow management systems are mainly data-flow oriented, which face several challenges due to the huge amount of data and the required computational capacity which cannot be predicted before enactment. Other problems may arise due to the dynamic access of the data storages or other data sources and the distributed nature of the scientific workflow computational infrastructures (cloud, cluster, grid, HPC), which status may change even during running of a single workflow instance. Many of these failures could be avoided with workflow management systems that provide provenance based dynamism and adaptivity to the unforeseen scenarios arising during enactment. In our work we summarize and categorize the failures that can arise in cloud environment during enactment and show the possibility of prediction and avoidance of failures with dynamic and provenance support.

Anna Bánáti, Eszter Kail, Péter Kacsuk, Miklos Kozlovszky

Graph-Transformational Swarms with Stationary Members

The concept of graph-transformational swarms is a novel approach that offers a rule-based framework to model discrete swarm methods. This paper continues the research on graph-transformational swarms by focusing on a special type of members called stationary members. The stationary members are assigned to particular subgraphs of the considered environment graphs. Every stationary member is responsible for calculations and transformations at the assigned area, and the applicability of the member’s rules depends only on this area and not on the whole environment. A further advantage of stationary members is that it is easier to guarantee that they can act in parallel than for moving members. Cloud computing is an engineering topic where swarms with stationary members can be applied in an adequate way, namely, by modeling the nodes of the server network that forms the cloud as stationary members. We illustrate the proposed concept by means of a case study.

Larbi Abdenebaoui, Hans-Jörg Kreowski, Sabine Kuske

Embedded Systems


Analysis and Generation of Logical Signals for Discrete Events Behavioral Modeling

This paper presents a proposal for structuring logical signals for discrete events behavioral modeling. Graphical formalisms will be used to illustrate applicability of the proposed techniques. Input logical signals are generated based on the analysis of physical signals coming from the environment and other input logical signals. Their analysis is introduced in the flow of the input signal analysis, defined as pre-processing when using a modeling formalism. Their analysis is done in the first step of pre-processing, allowing to put these signals at the same level of the physical ones, enabling its use in the rest of the signals’ analysis, and also allowing the generation of events and conditions associated with these signals. Likewise, logical signals are also defined in the flow of post-processing, allowing the definition of output logical signals through analysis and composition of the output signals generated by the model execution. The output logical signals are analyzed in the last step of post-processing in order to allow the use of the signals affected by the events in its analysis. The usage of these signals allows improvements in terms of expressiveness and compactness of the resulted models, both directly due to its use as well as by the increase of the possibilities of analysis provided to the following parts of the development flow.

Rogério Campos-Rebelo, Anikó Costa, Luis Gomes

EmbedCloud – Design and Implementation Method of Distributed Embedded Systems

This paper presents a novel design and implementation methodology of the distributed embedded systems, called EmbedCloud. It defines structured implementation model for each module in the system. EmbedCloud forms the basis for the automatic code generation algorithm of the distributed embedded systems which accelerates and simplifies synthesis process of such systems. The EmbedCloud utilizes CloudBus protocol demonstrated in previous publications, which provides a process synchronization and control mechanism for a number of processing units distributed in a network. The CloudBus protocol allows to significant savings in the amount of transmitted data between end modules in the distributed embedded system, especially when compared with the other protocols used in the industry. To verify and evaluate the performance of the EmbedCloud, a concurrent process was described using Petri nets. Hardware tests and synthesis verification of the distributed embedded system was performed on the testing platform built with AVR, ATmega series microcontrollers. The tests confirmed the correctness of the developed source code and EmbedCloud method. Furthermore, resource requirements and reaction time analysis were performed.

Kazimierz Krzywicki, Marian Adamski, Grzegorz Andrzejewski

Cloud Based IOPT Petri Net Simulator to Test and Debug Embedded System Controllers

IOPT-Tools is a cloud based integrated development environment to the design of embedded system controllers and other digital systems, employing the IOPT Petri net modeling formalism. The tools include a graphical editor, a state-space based model-checking subsystem and automatic code generators to deploy the controllers on the target hardware platforms. This paper presents a new Simulator tool that offers the capability to execute embedded system controllers based on IOPT models in a Web browser. To allow the test and debug of embedded system controllers, the Simulator provides options to manipulate the value of input signals, step by step execution, and continuous execution with programmed step frequency and breakpoint definition. Simulation history is recorded, continuously storing information about the entire system state, to enable playback and history navigation. History data can later be exported in spreadsheet format for analysis with external tools and waveform drawing. The tool can be accessed from

Fernando Pereira, Luis Gomes

Perception and Signal Processing


Improved Denoising with Robust Fitting in the Wavelet Transform Domain

In this paper we present a new method for thresholding the coefficients in the wavelet transform domain based on the robust local polynomial regression technique. It is proven that the robust locally-weighted smoother excellently removes the outliers or extreme values by performing iterative reweighting. The proposed method combines the main advantages of multiresolution analysis and robust fitting. Simulation results show efficient denoising at low resolution levels. Besides, it provides simultaneously high density impulse noise removal in contrast to other adaptive shrinkage procedures. Performance has been determined by using quantitative measures, such as signal to noise ratio and root mean square error.

Adrienn Dineva, Annamária R. Várkonyi-Kóczy, József K. Tar

Selection of Large-Scale 3D Point Cloud Data Using Gesture Recognition

An essential task when visualizing and analyzing large-scale 3D point cloud data is the selection of subsets of that data. This presents two challenges, the need for a selection method that is independent of the size of the dataset and how to interact with a 3D space effectively in a digital world still rooted in 2D interaction and visualization. We present an interface for defining volumes to select 3D point cloud data that uses hand gesture control with a Leap Motion device. The use of volumes is scalable to very large datasets, and the use of the Leap Motion gives the user access to the third dimension, facilitating interaction with the point cloud data. We illustrate with a large astronomical data archive hosted on the cloud that is retrieved on as-needed basis.

Robin Burgess, António J. Falcão, Tiago Fernandes, Rita A. Ribeiro, Miguel Gomes, Alberto Krone-Martins, André Moitinho de Almeida

Context Classifier for Service Robots

In this paper a context classifier for service robots is presented. Independently of the application, service robots need to have the notion of their context in order to behave appropriately. A context classification architecture that can be integrated in service robots reliability calculation is proposed. Sensorial information is used as input. This information is then fused (using Fuzzy Sets) in order to create a knowledge base that is used as an input to the classifier. The classification technique used is Bayes Networks, as the object of classification is partially observable, stochastic and has a sequential activity. Although the results presented refer to indoor/outdoor classification, the architecture is scalable in order to be used in much wider and detailed context classification. A community of service robots, contributing with their own contextual experience to dynamically improve the classification architecture, can use cloud-based technologies.

Tiago Ferreira, Fábio Miranda, Pedro Sousa, José Barata, João Pimentão

Distributed RSS-Based Localization in Wireless Sensor Networks with Node Selection Mechanism

In this work, we address the target localization problem in large-scale cooperative wireless sensor networks (WSNs). Using the noisy range measurements, extracted from the received signal strength (RSS) information, we formulate the localization problem based on the maximum likelihood (ML) criterion. ML-based solutions are particularly important due to their asymptotically optimal performance, but the localization problem is highly non-convex. To overcome this difficulty, we propose a convex relaxation leading to second-order cone programming (SOCP), which can be efficiently solved by interior-point algorithms. Furthermore, we investigate the case where target nodes limit the number of cooperating nodes by selecting only those neighbors with the highest RSS measurements. This simple procedure may decrease the energy consumption of an algorithm in both communication and computation phase. Our simulation results show that the proposed approach outperforms the existing ones in terms of the estimation accuracy. Moreover, they show that the new approach does not suffer significant degradation in its performance when the number of cooperating nodes is reduced.

Slavisa Tomic, Marko Beko, Rui Dinis, Goran Dimic, Milan Tuba

Signal Processing in Medicine


Continuous Speech Classification Systems for Voice Pathologies Identification

Voice pathologies identification using speech processing methods can be used as a preliminary diagnostic. The aim of this study is to compare the performance of sustained vowel /a/ and continuous speech task in identification systems to diagnose voice pathologies. The system recognizes between three classes consisting of two different pathologies sets and healthy subjects. The signals are evaluated using MFCC (Mel Frequency Cepstral Coefficients) as speech signal features, applied to SVM (Support Vector Machines) and GMM (Gaussian Mixture Models) classifiers. For continuous speech, the GMM system reaches 74% accuracy rate while the SVM system obtains 72% accuracy rate. For the sustained vowel /a/, the accuracy achieved by the GMM and the SVM is 66% and 69% respectively, a lower result than with continuous speech.

Hugo Cordeiro, Carlos Meneses, José Fonseca

3D Human Scanning Solution for Medical Measurements

Today anthropometry can be performed with three-dimensional scanners. Our aim is to establish a low-cost, easy-to-use hardware and software solution, which is capable to do automatic, computer-based anthropometry and medical measurements for health care. We have designed and build a large, remote controlled turntable and a 3D scanner application, which can be used to digitalize 0.2-2,6 m tall real world objects into 3D models. With the turntable a 360° field of view can be reached even when using completely stationary, static sensors. Our software uses RGBD sensors for data acquisition, however it can be combined with other image sensors. With our solution prosthesis design can be more accurate and simplified, and we can provide for 3D modelers an efficient, real time method to scan and visualize human scale 3D objects. The scanned models can easily be used for rapid prototyping and 3D printing. The models can be exported into the most popular 3D modeling file formats for further analysis. Our solution decreases significantly the time, effort and cost of the clean up process of the 3D scanning. In this paper we provide information about our 3D scanning solution’s design, and implementation, and we also describe its accuracy. The realized hardware and software solution provides a cheap and sufficiently reliable method to gather real time 3D depth and RGB data from human size objects for 3D reconstruction.

Balázs Sütő, Zsolt Könnyű, Zsolt Tölgyesi, Tibor Skala, Imre Rudas, Miklos Kozlovszky

Semi-Automated Quantitative Validation Tool for Medical Image Processing Algorithm Development

Cancer research and diagnostics is an important frontier to apply the power of computers. Researchers use image processing techniques for a few years now, but diagnostics only start to explore its possibilities. Pathologists specialized in this area usually diagnose by visual inspection, typically through a microscope, or more recently on a computer screen. They examine at tissue specimen or a sample consisting of a population cells extracted from it. The latter area is the area of cytometry that researchers started to support by creating image processing algorithms. The validation of an image processing approach like that is an expensive task both financially and time-wise. This paper aims to show a semi-automatized method to simplify this task, by reducing the amount of human interaction necessary.

Viktor Zoltan Jonas, Miklos Kozlovszky, Bela Molnar

High Resolution Digital Tissue Image Processing using Texture Image Databases

Texture based image databases integrated with effective searching algorithms are useful solutions for many scientific and industrial purposes. Medical image processing of high resolution tissue images is one of the areas, where the cell/tissue classification can rely on such solutions. In this paper we are describing the design, development and usage of a specialized medical texture image database. Our primary aim with this texture database is to provide Digital Imaging and Communication in Medicine (DICOM) compatible texture image dataset for cell, gland and epithelium classification in histology. Our solution includes a Picture Archiving and Communication System (PACS) subsystem, which is mainly provide a communication interface (texture image searching and retrieval) and enables image processing algorithms to work more effectively on high resolution tissue slide images. In this paper we describe how our Local Binary Pattern (LBP) based algorithm benefits texture database usage when solving image processing problems in histology and histopathology.

Gábor Kiss, Orsolya Eszter Cseri, Ádám Altsach, István Imre Bándi, Levente Kovács, Miklos Kozlovszky

Smart Monitoring Systems


Georeferenced Dynamic Event Handling

A fast and efficient response to hazardous events can make the difference between life and death. Using this necessity as premise, surveillance systems are evolving, increasing the number of sensors used in event detection and developing new methods and algorithms for events handling. Nevertheless the timeliness and efficiency of response to events could be improved using new technologies, such as mobile devices with GPS capabilities, georeferenced location of events, and event classification. Having access to events and security agents’ locations could improve event’s handling in terms of responsiveness and appropriate distribution of work load per agent. Under the scope of a research project Advanced Surveillance System (DVA) a new approach to surveillance systems based in this geographic position of sensors, detected events and security agents was developed. DVA implements new algorithms for events’ assignment and processing. This paper describes DVA’s new approach to event handling.

Sérgio Onofre, João Paulo Pimentão, Pedro Sousa

Implementation of User-Oriented Smart Services into an Innovative DC Low Voltage Net

In this paper a concept of smart services implemented in an innovative DC net (direct current) is described. It shows how various components with different DC-energy-level-demands and user-based requirements can be connected interoperable. Thus smart services can be defined in that technical environment. The implemented system is able to remember the residents’ individual preferences to provide a comfortable living situation.

Manja Görner, Thomas Göschel, Stephan Kassel, Thomas Klein, Sabrina Sander

Light Memory Operation Based on a Double Pin SiC Device

Experimental optoelectronic characterization of a p-i’(a-SiC:H)-n/p-i(a-Si:H)-n heterostructure with low conductivity doped layers shows the feasibility of tailoring channel bandwidth and wavelength by optical bias through back and front side illumination. Front background enhances light-to-dark sensitivity of the long and medium wavelength range, and strongly quenches the others. Back violet background enhances the magnitude in short wavelength range and reduces the others. Experiments have three distinct programmed time slots: control, hibernation and data. Throughout the control time slot steady light wavelengths illuminate either or both sides of the device, followed by the hibernation without any background illumination. The third time slot allows a programmable sequence of different wavelengths with an impulse frequency of 6000H


to shine upon the sensor. Results show that the control time slot illumination has an influence on the data time slot which is used as a volatile memory with the set, reset logical functions.

V. Silva, M. Barata, M. A. Vieira, P. Louro, M. Vieira

Brain Inspired Health Monitoring Supported by the Cloud

The health status of a person can be assessed by specialized professionals with the help of medical devices. The assessment, in real-time, would be useful as most of the times a person is not in presence of health professionals. But own assessment lacks precision and reaction time that could be risky in critical conditions. The pervasiveness of Internet connections and ubiquity of smart devices makes it possible to overcome that limitation. By using sensing capabilities of portable/wearable devices in conjunction with medical knowledge and clinical history it is possible to monitor a person’s health status in real-time with reaction mechanisms. The objective is to keep track of collected evidence, and relate with existing knowledge for better assessment. This paper proposes a framework, inspired by the brain and physiology, capturing real-time health related information, at a person’s location, submitting that to the cloud for reasoning and decision and triggers advice or request medical assistance.

Fernando Luis-Ferreira, Sudeep Ghimire, Ricardo Jardim-Goncalves

Renewable Energy


Optimal Generation Scheduling of Wind-CSP Systems in Day-Ahead Electricity Markets

This paper presents a coordination approach to maximize the total profit of wind power systems coordinated with concentrated solar power systems, having molten-salt thermal energy storage. Both systems are effectively handled by mixed-integer linear programming in the approach, allowing enhancement on the operational during non-insolation periods. Transmission grid constraints and technical operating constraints on both systems are modeled to enable a true management support for the integration of renewable energy sources in day-ahead electricity markets. A representative case study based on real systems is considered to demonstrate the effectiveness of the proposed approach.

H. M. I. Pousinho, P. Freire, J. Esteves, V. M. F. Mendes, C. Pereira Cabrita, M. Collares-Pereira

Influence of Large Renewable Energy Integration on Insular Grid Code Compliance

Large-scale deployment of renewables in island energy systems attracts local attention of grid operators as a way of reducing fuel fossil consumption. Planning a grid based on renewable power plants poses serious challenges to the normal operation of a power system, namely on frequency and voltage stability. In past grid code compliance, wind turbines did not require services for supporting grid operation. To shift to large renewable energy integration, the island grid code should incorporate a new set of requirements in order to regulate the inclusion of these services, which is the aim of this paper. The paper also discusses additional requirements such as “virtual” wind inertia.

Eduardo M. G. Rodrigues, Radu Godina, Tiago D. P. Mendes, João C. O. Matias, João P. S. Catalão

Optimal Behavior of Demand Response Aggregators in Providing Balancing and Ancillary Services in Renewable-Based Power Systems

Due to the limited predictability and associated uncertainty of renewable energy resources, renewable-based electricity systems are confronted with instability problems. In such power systems, implementation of Demand Response (DR) programs not only can improve the system stability but also enhances market efficiency and system reliability. By implementing cloud-based engineering systems the utilization of DR will be increased and consequently DR will play a more crucial role in the future. Therefore, DR aggregators can efficiently take part in energy, balancing and ancillary services markets. In this paper, a model has been developed to optimize the behavior of a DR aggregator to simultaneously participate in the mentioned markets. To this end, the DR aggregator optimizes its offering/bidding strategies based on the contracts with its customers. In the proposed model, uncertainties of renewable energy resources and the prices of electricity markets are considered. Numerical studies show the effectiveness of the proposed model.

E. Heydarian-Forushani, M. E. H. Golshan, M. Shafie-khah, João P. S. Catalão

A Heuristic Approach for Economic Dispatch Problem in Insular Power Systems

Insular power systems are characterized by their isolated geographical location, which makes their interconnection with other power systems a challenging task. Moreover, these islands have important renewable resources that allow the reduction of generation costs and greenhouse gas emissions (GHE). To guaranty the quality, flexibility and robustness of the electrical framework, the representation of renewable power forecasting error by scenario generation or even the implementation of demand response tools have been adopted. In this paper, the failure events of a specific unit are considered according to its capacity. Then, using the forced outage rate, the probability of each failure event is computed. Results of energy not supplied and fuel consumption cost are determined by applying probabilistic concepts, while the final results are obtained by fitting and evaluating a nonlinear trend line carried out using the previous results, resulting in a proficient computational tool compared with classical ones.

G. J. Osório, J. M. Lujano-Rojas, João C. O. Matias, João P. S. Catalão

Energy: Management


Experimental Wireless Wattmeter for Home Energy Management Systems

This paper presents a novel prototype device for domestic load energy consumption monitoring. Zigbee-based wireless connectivity is included as a basic feature of the prototype. The proposed device allows individual tracking of major energy consumption loads. Real time energy data is acquired and transmitted through a RF link to a wireless terminal unit, which works as a data logger and as a human-machine interface. Both voltage and current measurements are implemented using Hall Effect principle based transducers, while C code is developed on two 16-bit RISC MCU. The experimental setup is described and tests are conducted in order to assess its performance.

Eduardo M. G. Rodrigues, T. Caramelo, Tiago D. P. Mendes, Radu Godina, João P. S. Catalão

Use of Web Based Meters to Improve Energy Efficiency and Power Quality in Buildings

During the work conducted, several buildings were analysed, in terms of energy efficiency and power quality. Two case studies are here presented: an educational building and a museum. Most of the studies were conducted recurring to traditional measurement equipment, forcing the person to travel to the site to install equipment and every time he wanted to collect data. But one of the case studies, the museum, comprised the development of an analyser (hardware and software) able to measure electric energy, temperature and humidity. This analyser has the capability to register values on a database available in the internet and issue warnings to the building manager. This allows real-time information, supporting some energy efficiency actions. The objective is to improve this model and expand its use for several buildings, providing savings in terms of time and other resources, taking advantage of cloud-based systems.

Licínio Moreira, Sérgio Leitão, Zita Vale, João Galvão

A Model-Based Approach for Resource Constrained Devices Energy Test and Simulation

The constant evolution in communication technologies, has improved during the last decades the interaction between systems/devices/things/etc. Internet-of-Things (IoT) has become the last trend pushing forward in this direction, connecting all ‘things’, creating a sensing world around all of us. Although, IoT technologies, solutions, systems have to be proven/tested before deployment in the real settings. These decentralized systems normally use low power devices with small processing and storage capabilities, with roles mainly of sensing and data transmission. Until now, tests and energy simulation focus on wireless communications, since it has been identified as the main energy consuming module. This paper presents the acquisition and simulation of energy consumption by a single device, focused on all hardware components and not only in the communication, due to the new adopted solutions that do not rely so much in the communication (e.g. subscription). In this sense, a methodology capable of retrieving real and simulated energy consumption results from/for a single device is presented, relying on a model based approach (software, hardware, energy and simulation models) and on a precise energy consumption assessment system. It is also presented a Resource Constrained Device Model, capable of representing the available hardware in a device, and a circuit to retrieve more accurate energy consumption readings.

Edgar M. Silva, Luis Gomes, João Rodrigues, Pedro Maló

Energy: Improvement


Analysis of Causes and Effects of Harmonic Distortion in Electric Power Systems and Solutions to Comply with International Standards Regarding Power Quality

In recent years, power quality has gained importance due to increasing pollution in the electric system as a consequence of the proliferation of non-linear loads connected to the grid. For this reason, research has been intensified on this issue to improve power quality; especially through simulation models development using software tools, which allow studying the possible causes and effects of disturbances on the electric system and testing solutions to mitigate these power quality events. This paper focuses on analyzing by simulation a possible cause, effect and solution of harmonic distortion, as an example of using cloud-based platforms in order to get the power quality requirements of the future Smart Grid.

Mercedes Ruiz-Cortés, María Isabel Milanés-Montero, Fermín Barrero-González, Enrique Romero-Cadaval

Risk Analysis and Behavior of Electricity Portfolio Aggregator

The scope of this paper is to adapt the standard mean-variance model of Henry Markowitz theory, creating a simulation tool to find the optimal configuration of the portfolio aggregator, calculate its profitability and risk. Currently, there is a deep discussion going on among the power system society about the structure and architecture of the future electric system. In this environment, policy makers and electric utilities find new approaches to access the electricity market; this configures new challenging positions in order to find innovative strategies and methodologies. Decentralized power generation is gaining relevance in liberalized markets, and small and medium size electricity consumers are also become producers (“prosumers”). In this scenario an electric aggregator is an entity that joins a group of electric clients, customers, producers, “prosumers” together as a single purchasing unit to negotiate the purchase and sale of electricity. The aggregator conducts research on electricity prices, contract terms and conditions in order to promote better energy prices for their clients and allows small and medium customers to benefit improved market prices.

Eduardo Eusébio, Jorge de Sousa, Mário Ventim Neves

Combined Operation of an Unified Power Quality Conditioner and a Superconducting Magnetic Energy Storage System for Power Quality Improvement

Superconducting Magnetic Energy Storage (SMES) is a class of promising superconducting devices, considering its possible applications in power systems. This paper describes a combination of a SMES with a Unified Power Quality Conditioner (UPQC) for power quality improvement in an electric grid. The SMES device is used to improve the UPQC performance by increasing the stored energy in the DC link. Several power quality faults including voltage sags and current harmonics are simulated and the system behavior is demonstrated. This hybrid system has the advantage of being able to overcome different kinds of power quality faults with higher performance than as a set of individual systems, thus increasing power quality in electric grids.

Nuno Amaro, Luís Casimiro, João Murta Pina, João Martins, José M. Ceballos

Energy: Decision Support


Offering Strategies of Wind Power Producers in a Day-Ahead Electricity Market

This paper presents a stochastic optimization-based approach applied to offer strategies of a wind power producer in a day-ahead electricity market. Further from facing the uncertainty on the wind power the market forces wind power producers to face the uncertainty of the market-clearing electricity price. Also, the producer faces penalties in case of being unable to fulfill the offer. An efficient mixed-integer linear program is presented to develop the offering strategies, having as a goal the maximization of profit. A case study with data from the Iberian Electricity Market is presented and results are discussed to show the effectiveness of the proposed approach.

R. Laia, H. M. I. Pousinho, R. Melício, V. M. F. Mendes, M. Collares-Pereira

New Multi-objective Decision Support Methodology to Solve Problems of Reconfiguration in the Electric Distribution Systems

The distribution systems (DS) reconfiguration problem is formulated in this paper as a multi-objective mixed-integer linear programming (MILP) multi-period problem, enforcing that the obtained topology is radial in order to exploit several advantages those configurations offer. The effects of distributed generation (DG) and energy storage systems (ESS) are also investigated. To address the multi-objective problem, an improved implementation of the ε-constraint method (AUGMECON-2) is used, providing an adequate representation of the Pareto set. The objective functions considered stand for the minimization of active power losses and the minimization of switching operations. The proposed methodology is tested using a real system based on the S. Miguel Island, Azores, Portugal. The potential uses of cloud-based engineering systems, both in terms of exploiting the enhanced decentralized computational opportunities they offer and of utilizing them in order to achieve communication and coordination between several entities that are engaged in DS, are thoroughly discussed.

Sérgio F. Santos, Nikolaos G. Paterakis, João P. S. Catalão

Cloud-Based Decision Support Ecosystem for Renewable Energy Providers

The increasing complexity of decision making environments requires new approaches that can improve the efficiency, the effectiveness and the quality of the decision making processes. Cloud-based Decision Support Ecosystems (DSE) create the premises for the next generation of DSS, by modeling dynamic system architectures and customizable decision layers that instantiate a new level of independence at end-user level. End-users are able to connect new data sources to the decision making processes without assistance from software developers, while maintain consistency, to build more relevant decision environments. The authors discuss key challenges associated with the DSE and present the design premises of a cloud-based DSE for renewable energy providers. The paper builds upon the PhD research carried out within the INDESEN Project, funded by Unitatea Executiva pentru Finantarea Invatamantului Superior, a Cercetării, Dezvoltării si Inovarii (UEFISCDI) through the Romanian Partnership Program.

Ioana Andreea Stănescu, Antoniu Ştefan, Florin Gheorghe Filip

Energy: Simulation


Development of a Simulink Model of a Saturated Cores Superconducting Fault Current Limiter

Superconducting fault current limiters are considered as emerging devices for the advent of modern power grids. Those limiters as well as other electric power grid applications have been developed in the last years in order to support the increased penetration of dispersed generation. The development of such limiters requires new design tools that allows to simulate those devices in electrical power grids with different voltage ratings and characteristics. This work presents a methodology to simulate the behaviour of saturated core type limiters based on its characteristic curves. A prototype is tested to obtain its characteristic and then the methodology is implemented in Simulink. The simulation carried out by the proposed methodology is compared with a real test.

Nuno Vilhena, Pedro Arsénio, João Murta-Pina, Anabela Gonçalves Pronto, Alfredo Álvarez

Simulation of a-Si PV System Linked to the Grid by DC Boost and Three-Level Inverter Under Cloud Scope

This paper is about a PV system linked to the electric grid through power converters under cloud scope. The PV system is modeled by the five parameters equivalent circuit and a MPPT procedure is integrated into the modeling. The modeling for the converters models the association of a DC-DC boost with a three-level inverter. PI controllers are used with PWM by sliding mode control associated with space vector modulation controlling the booster and the inverter. A case study addresses a simulation to assess the performance of a PV system linked to the electric grid. Conclusions regarding the integration of the PV system into the electric grid are presented.

L. Fialho, R. Melício, V. M. F. Mendes, M. Collares-Pereira

Modeling Reserve Ancillary Service as Virtual Energy Carrier in Multi-Energy Systems

Multi-energy systems (MES) are considered various energy carriers and energy players in an integrated energy model. Vast amount of decision making data is gathered in these systems that cannot be processed by conventional methods. Cloud-based computing is an opportunity to develop these kinds of integrated and efficient approaches. Developing mathematical models that can be compatible with cloud-based engineering systems will help decision makers to enhance the system agendas in short to long term studies. In this paper, the energy hub approach is developed to consider electric reserve ancillary service in MES. The reserve is modeled as a virtual energy output that can be injected into the upstream network. The reserve service is defined for electric energy converters and storages, comprehensively. Therefore, the energy hub mathematical model is developed and new elements are added to the input and output vectors and system conversion matrix. For energy converters, reserve is defined as the capability of the converter to increase its output service to its maximum operational limits. Moreover, for electric storages this capability is also restricted by storages’ state of charges. The numerical results demonstrate the importance of reserve considerations in MESs and allow assessing the proficiency of the proposed model.

M. Y. Damavandi, Mohsen Parsa Moghaddam, M.-R. Haghifam, M. Shafie-khah, João P. S. Catalão

Simulation of Offshore Wind System with Three-Level Converters: HVDC Power Transmission in Cloud Scope

This paper is on a simulation for offshore wind systems in deep water under cloud scope. The system is equipped with a permanent magnet synchronous generator and a full-power three-level converter, converting the electric energy at variable frequency in one at constant frequency. The control strategies for the three-level are based on proportional integral controllers. The electric energy is injected through a HVDC transmission submarine cable into the grid. The drive train is modeled by a three-mass model taking into account the resistant stiffness torque, structure and tower in the deep water due to the moving surface elevation. Conclusions are taken on the influence of the moving surface on the energy conversion.

M. Seixas, R. Melício, V. M. F. Mendes, M. Collares-Pereira, M. P. dos Santos

Energy: Power Conversion I


Disc Motor with Rotor Made of Aluminium or Polycrystalline High Temperature Superconductor

The discovery of the superconductivity and the understanding of electromagnetic properties of high temperature superconducting (HTS) materials allowed the optimization and development of several applications, such as electrical machines and drives. Electromechanical conversion devices based in HTS materials potentially allows for reduction in devices dimensions or performance improvement for the same active volume, when compared with their conventional ones.An axial disc motor with high temperature superconductor (HTS) material or conventional aluminium in the rotor and conventional armature has been designed and developed. This paper describes simulations and laboratory experiments performed at liquid nitrogen temperature (77 K) in order to analyze the motor’s behaviour and its electromechanical characteristics and to define an electric equivalent circuit that allows describing its operation. From the obtained results it was observed that the tested HTS behaves as a conventional hysteresis motor even though with a different nature. On the other hand, the motor with aluminium rotor behaves as a conventional induction motor. In asynchronous regime, the HTS motor exhibits a constant torque, higher than the conventional aluminium one.

David Inácio, João Murta Pina, Mário Ventim Neves, Alfredo Álvarez

Investigation of the Tesla Transformer as a Device for One-Wire Power and Signaling and as a Device for Power and Signaling Through the Ground

A new method for power and communications through single wire or the ground as a medium is investigated. The focus of the research is based on the proper construction and operation of a Tesla Transformer, so as to be able to transmit power and/or signals through one wire or the ground. The conclusions are based upon experimental data. There are successful results for single wire power supply with efficiency of about 20%. There is room for improvement of the circuits, so better efficiency is expected. The utilization of the soil as a medium for currents propagation didn’t give any useful results. Due to its complex properties, the ground transmission requires lower working frequency, hence bigger and more complicated coils, special drive circuit and good grounding.

Kaloyan Mihaylov, Rui Neves-Medeiros, Rumen Arnaudov, Stanimir Valtchev

Experimental Magnetic Field Mapping of a Polycrystalline Superconducting YBCO Disc for an Axial Flux Motor

The method of creating large and complex-shaped melt-textured YBCO bulks based in artificial welding seeds opens the door to the study of applications with polycrystalline superconductor samples. In order to evaluate the superconducting quality of the bulks, Hall probe mapping can be applied in order to measure trapped flux field profiles after magnetisation. This paper describes the magnetic field mapping of an axial flux motor with a polycrystalline high temperature superconductor (YBCO) disc rotor at liquid nitrogen temperature (77 K). An axial flux hall probe is used and magnetic field profiles have been obtained for different polar configurations of a three-phase stator winding which will be operated at 50Hz. After the magnetization of the HTS disc trapped flux is measured, and its magnitude depends on the polar configuration and magnitude of the applied field.

David Inácio, João Murta Pina, José Maria Ceballos, Mário Ventim Neves, Alfredo Álvarez

Energy: Power Conversion II


Analysis of a Multi-Ratio Switched Capacitor DC-DC Converter for a Supercapacitor Power Supply

An energy harvesting system can use a supercapacitor in order to store energy; however, a voltage regulator is required to obtain a constant output voltage as the supercapacitor discharges. A Switched-Capacitor DC-DC converter allows for complete integration in CMOS technology, but requires several topologies in order to obtain a high efficiency. This paper presents the complete analysis of these topologies in order to determine expressions that allow to design and determine the optimum input voltage ranges for each topology. These expressions are verified using electrical simulations.

Hugo Serra, Ricardo Madeira, Nuno Paulino

A Piezoelectric Device for Measurement and Power Harvesting Applications

With the fast growth of wireless communications between nodes/sensor units, devices installed in remote places require power energy supply solutions to assure their functionally and data communication capabilities. For these applications energy harvesting takes place as a good solution, to increase the availability of energy, in opposition to the conventional systems of energy supply. Regenerative energy sources like thermoelectric, magnetic, piezoelectric, and/or renewable sources such as photovoltaic, wind, among others, allowed the development of different powering solutions for sensor units. The purpose of this work is to characterize a piezoelectric device to measure and capture mechanical vibrations from equipments, structures and piping vibrations, as well as from other sources. The study is carried out taking into account the power supply capabilities of piezoelectric devices as a function of the amplitude and frequency of the vibration stimulus, as well as, the electrical characteristics of the load circuit.

M. Alves, J. M. Dias Pereira, J. M. Fonseca

Design of High Voltage Full-Bridge Inverter Using Marx Derived Switches

This paper presents a high–voltage (HV) inverter to generate bipolar voltages with variable duty-cycle and frequency for HV pulsed power or HV electrical network applications. Each one of the four HV inverter switches is built with a series stack of semiconductor devices, derived from the Marx generator concept, using small capacitors to equally share the voltage among the individual series stacked semiconductors. A sliding mode control is used to control the output voltage and a delay technique is used to reduce


at the HV inverter output and to balance the capacitor voltages. The design and structure of the HV inverter switches is described together with the delay technique. Steady-state and dynamic behavior is evaluated. Simulation results are presented (using MATLAB/Simulink software) and discussed.

Nelson Santos, J. Fernando Silva, Vasco Soares, Sónia F. Pinto, Duarte Sousa

Stable Integration of Power Electronics-Based DG Links to the Utility Grid with Interfacing Impedance Uncertainties

For the integration of distributed generation (DG) units to the utility grid, voltage source converter (VSC) is the key technology. In order to realize high quality power injection, different control techniques have been adopted. However, the converter-based DG interface is subject to inevitable uncertainties, which adversely influence the performance of the controller. The interfacing impedance seen by the VSC may considerably vary in real distribution networks. It can be observed that the stability of the DG interface is highly sensitive to the impacts of interfacing impedance changes so that the controller cannot inject appropriate currents. To deal with the instability problem, this paper proposes an enhanced fractional order active sliding mode control scheme for integration of DG units to the utility grid, which is much less sensitive to interfacing impedance variations. A fractional sliding surface which demonstrates the desired dynamics of the system is developed and then the controller is designed in two phases: sliding phase and reaching phase to keep the control loop stable. The proposed controller takes a role to provide high quality power injection and ensures precise current tracking and fast response despite uncertainties. Theoretical analyses and simulation results are verified to study the performance and feasibility of the proposed control scheme.

S. Kazem Hoseini, Edris Pouresmaeil, Jafar Adabi, João P. S. Catalão


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