Comparative analysis of the systems engineering method based on multi-agent

This paper consider a comparison of the systems engineering methods that incorporate the analysis of the businessprocesses of organizational-technical systems. The systems engineering method now proposed deals with the analysis of the man-machine distributed system data flow bottlenecks and reliability level in terms of the business processes execution time limits and takes into account the dynamics of the business processes. On the basis of comparative analysis fulfilled authors concluded the preeminence of their development method.В данной работе приводится сравнение методов разработки информационных систем, которые учитывают анализ процессов организационно-технических систем. Предлагаемый метод направлен на анализ узких мест и надежности человеко-машинной распределенной системы в условиях ограничений по срокам выполнения бизнес-процессов, учитывает динамику бизнес-процессов при разработке информационных систем. В результате проведенного сравнительного анализа сделан вывод о преимуществе метода, предлагаемого авторами

Simulation-based fitness landscape analysis and optimisation of complex problems

Widespread hard optimisation problems in economics and logistics are characterised by large dimensions, uncertainty and nonlinearity and require more powerful methods of stochastic optimisation that traditional ones. Simulation optimisation is a powerful tool for solving these problems. Moreover, fitness landscape analysis techniques provide an efficient approach to better selection of a suitable optimisation algorithm. The concept and techniques of fitness landscape analysis are described. A formalised scheme for simulation optimisation enhanced with fitness landscape analysis is given. Benchmark fitness landscape analysis is performed to find relations between efficiency of an optimisation algorithm and structural features of a fitness landscape. Case study in simulation optimisation of vehicle routing and scheduling is described. Various optimisation scenarios with application of the fitness landscape analysis are discussed and investigated

DAG-Based Attack and Defense Modeling: Don't Miss the Forest for the Attack Trees

This paper presents the current state of the art on attack and defense modeling approaches that are based on directed acyclic graphs (DAGs). DAGs allow for a hierarchical decomposition of complex scenarios into simple, easily understandable and quantifiable actions. Methods based on threat trees and Bayesian networks are two well-known approaches to security modeling. However there exist more than 30 DAG-based methodologies, each having different features and goals. The objective of this survey is to present a complete overview of graphical attack and defense modeling techniques based on DAGs. This consists of summarizing the existing methodologies, comparing their features and proposing a taxonomy of the described formalisms. This article also supports the selection of an adequate modeling technique depending on user requirements

Breast cancer diagnosis using an efficient CAD system based on multiple classifiers

Breast cancer is one of the major health issues across the world. In this study, a new computer-aided detection (CAD) system is introduced. First, the mammogram images were enhanced to increase the contrast. Second, the pectoral muscle was eliminated and the breast was suppressed from the mammogram. Afterward, some statistical features were extracted. Next, k-nearest neighbor (k-NN) and decision trees classifiers were used to classify the normal and abnormal lesions. Moreover, multiple classifier systems (MCS) was constructed as it usually improves the classification results. The MCS has two structures, cascaded and parallel structures. Finally, two wrapper feature selection (FS) approaches were applied to identify those features, which influence classification accuracy. The two data sets (1) the mammographic image analysis society digital mammogram database (MIAS) and (2) the digital mammography dream challenge were combined together to test the CAD system proposed. The highest accuracy achieved with the proposed CAD system before FS was 99.7% using the Adaboosting of the J48 decision tree classifiers. The highest accuracy after FS was 100%, which was achieved with k-NN classifier. Moreover, the area under the curve (AUC) of the receiver operating characteristic (ROC) curve was equal to 1.0. The results showed that the proposed CAD system was able to accurately classify normal and abnormal lesions in mammogram samples

Optimal Control of Hybrid Systems and Renewable Energies

This book is a collection of papers covering various aspects of the optimal control of power and energy production from renewable resources (wind, PV, biomass, hydrogen, etc.). In particular, attention is focused both on the optimal control of new technologies and on their integration in buildings, microgrids, and energy markets. The examples presented in this book are among the most promising technologies for satisfying an increasing share of thermal and electrical demands with renewable sources: from solar cooling plants to offshore wind generation; hybrid plants, combining traditional and renewable sources, are also considered, as well as traditional and innovative storage systems. Innovative solutions for transportation systems are also explored for both railway infrastructures and advanced light rail vehicles. The optimization and control of new solutions for the power network are addressed in detail: specifically, special attention is paid to microgrids as new paradigms for distribution networks, but also in other applications (e.g., shipboards). Finally, optimization and simulation models within SCADA and energy management systems are considered. This book is intended for engineers, researchers, and practitioners that work in the field of energy, smart grid, renewable resources, and their optimization and control

μGIM - Microgrid intelligent management system based on a multi-agent approach and the active participation of end-users

[ES] Los sistemas de potencia y energía están cambiando su paradigma tradicional, de sistemas centralizados a sistemas descentralizados. La aparición de redes inteligentes permite la integración de recursos energéticos descentralizados y promueve la gestión inclusiva que involucra a los usuarios finales, impulsada por la gestión del lado de la demanda, la energía transactiva y la respuesta a la demanda. Garantizar la escalabilidad y la estabilidad del servicio proporcionado por la red, en este nuevo paradigma de redes inteligentes, es más difícil porque no hay una única sala de operaciones centralizada donde se tomen todas las decisiones. Para implementar con éxito redes inteligentes, es necesario combinar esfuerzos entre la ingeniería eléctrica y la ingeniería informática. La ingeniería eléctrica debe garantizar el correcto funcionamiento físico de las redes inteligentes y de sus componentes, estableciendo las bases para un adecuado monitoreo, control, gestión, y métodos de operación. La ingeniería informática desempeña un papel importante al proporcionar los modelos y herramientas computacionales adecuados para administrar y operar la red inteligente y sus partes constituyentes, representando adecuadamente a todos los diferentes actores involucrados. Estos modelos deben considerar los objetivos individuales y comunes de los actores que proporcionan las bases para garantizar interacciones competitivas y cooperativas capaces de satisfacer a los actores individuales, así como cumplir con los requisitos comunes con respecto a la sostenibilidad técnica, ambiental y económica del Sistema. La naturaleza distribuida de las redes inteligentes permite, incentiva y beneficia enormemente la participación activa de los usuarios finales, desde actores grandes hasta actores más pequeños, como los consumidores residenciales. Uno de los principales problemas en la planificación y operación de redes eléctricas es la variación de la demanda de energía, que a menudo se duplica más que durante las horas pico en comparación con la demanda fuera de pico. Tradicionalmente, esta variación dio como resultado la construcción de plantas de generación de energía y grandes inversiones en líneas de red y subestaciones. El uso masivo de fuentes de energía renovables implica mayor volatilidad en lo relativo a la generación, lo que hace que sea más difícil equilibrar el consumo y la generación. La participación de los actores de la red inteligente, habilitada por la energía transactiva y la respuesta a la demanda, puede proporcionar flexibilidad en desde el punto de vista de la demanda, facilitando la operación del sistema y haciendo frente a la creciente participación de las energías renovables. En el ámbito de las redes inteligentes, es posible construir y operar redes más pequeñas, llamadas microrredes. Esas son redes geográficamente limitadas con gestión y operación local. Pueden verse como áreas geográficas restringidas para las cuales la red eléctrica generalmente opera físicamente conectada a la red principal, pero también puede operar en modo isla, lo que proporciona independencia de la red principal. Esta investigación de doctorado, realizada bajo el Programa de Doctorado en Ingeniería Informática de la Universidad de Salamanca, aborda el estudio y el análisis de la gestión de microrredes, considerando la participación activa de los usuarios finales y la gestión energética de lascarga eléctrica y los recursos energéticos de los usuarios finales. En este trabajo de investigación se ha analizado el uso de conceptos de ingeniería informática, particularmente del campo de la inteligencia artificial, para apoyar la gestión de las microrredes, proponiendo un sistema de gestión inteligente de microrredes (μGIM) basado en un enfoque de múltiples agentes y en la participación activa de usuarios. Esta solución se compone de tres sistemas que combinan hardware y software: el emulador de virtual a realidad (V2R), el enchufe inteligente de conciencia ambiental de Internet de las cosas (EnAPlug), y la computadora de placa única para energía basada en el agente (S4E) para permitir la gestión del lado de la demanda y la energía transactiva. Estos sistemas fueron concebidos, desarrollados y probados para permitir la validación de metodologías de gestión de microrredes, es decir, para la participación de los usuarios finales y para la optimización inteligente de los recursos. Este documento presenta todos los principales modelos y resultados obtenidos durante esta investigación de doctorado, con respecto a análisis de vanguardia, concepción de sistemas, desarrollo de sistemas, resultados de experimentación y descubrimientos principales. Los sistemas se han evaluado en escenarios reales, desde laboratorios hasta sitios piloto. En total, se han publicado veinte artículos científicos, de los cuales nueve se han hecho en revistas especializadas. Esta investigación de doctorado realizó contribuciones a dos proyectos H2020 (DOMINOES y DREAM-GO), dos proyectos ITEA (M2MGrids y SPEAR), tres proyectos portugueses (SIMOCE, NetEffiCity y AVIGAE) y un proyecto con financiación en cascada H2020 (Eco-Rural -IoT)

Simulation Models in eGovernment Using System Dynamics

Doktorgradsavhandling ved Universitetet i Agder, Institutt for infomasjons- og kommunikasjonsteknologi, 2017System Dynamics (SD) is a method to build simulation models using computers, to study the behaviour of systems, and apply what-if scenarios aiming at achieving optimal policy design. In this thesis, we are introducing an SD approach in modelling the eGovernment. The thesis is based on two topics or essays: eParticipation and eAccessibility as examples of eGovernment areas that SD models have not been used in before, to show how SD can be used in modelling and supporting decisions in the field of eGovernment, especially in new areas. Although this research is part of the eGovMon project1 where the use of SD method is indicated, via a literature review we shed light on the mathematical modelling methods commonly used in the eGovernment field, and a comparison between the suitable methods and SD is sketched showing the benefits of and our rationale behind choosing SD. eParticipation aims at linking ordinary people with politics and politicians by making the policymaking process understandable and easy to follow via Information and Communication Technologies. To apply this concept, we were interested in finding a topic of public interest that needs to be highlighted and promoted. Employment policies for Persons with Disabilities (PWD)2 including factors that prevent or promote them to move from welfare recipients to join the labour force in Norway, is such a topic. The employment rate for PWD in Norway is unchanged since 2000, and is not as high as the neighbouring countries, despite the repeated governmental promises. Under this topic, we have administered two questionnaires, one of them towards PWD and another towards potential employers. The PWD questionnaire covered PWD attitudes towards employment in Norway, including information about the factors enabling them to work, encouraging them to take available work opportunities, and preventing them from active job application. Corre-spondingly, the second questionnaire covered the attitudes of employers towards recruiting PWD in Norway, including factors encouraging employers to, and preventing them from recruiting PWD, as well as information related to employers’ awareness of facts about PWD employment. The results were incorporated in an SD model which focuses on enabling PWD to move from welfare to work. The model is intended to be used by policymakers, disability organisations, and individual citizens, and support more targeted discussions among them. Additionally, this model was encapsulated in an Interactive Learning Environment (ILE). To explore how the model could change how its users think and take decisions, the ILE was assessed by an expert opinion poll, and tested with users in two different experiments. 67% of the sample of our expert opinion poll thinks that the ILE achieves its intended goals. Furthermore, 71% of the candidates of both experiments have redefined certain knowledge as a result of using the ILE. eAccessibility of a website refers to the ability of all people to use this website irrespective of their disabilities or the client devices they use to access the Internet. It is an important aspect of websites in general and of public websites in particular. Access to public websites is crucial to assure equal opportunities for all citizens to participate in the society. The government exerts efforts to enhance accessibility, yet there is still room for improvement. Many ways could be proposed to enhance accessibility. However, the impact of selected actions is hard to predict due to diversification and contra-diction, in addition to the continuous change of the system over time. Under this topic, we have analysed questionnaires collected via a couple of surveys on eGovernment measurement methods, in addition to administering another questionnaire and a sample of webpages to classify the Norwegian municipal website accessi-bility failures according to their original causes. Moreover, we have conducted a set of personal interviews with representatives from municipalities. The findings including factors affecting the accessibility of the municipal websites were compiled into an SD model, which is intended to support policymakers’ and website managers’ decisions, and to enhance their mental models. This SD model was also encapsulated in an ILE, which was used in an experiment with users. Results show that 80% of the experiment candidates have redefined certain knowledge as a result of using this ILE

Modelling and performance evaluation of wireless and mobile communication systems in heterogeneous environments

It is widely expected that next generation wireless communication systems will be heterogeneous, integrating a wide variety of wireless access networks. Of particular interest recently is the integration of cellular networks (GSM, GPRS, UMTS, EDGE and LTE) and wireless local area networks (WLANs) to provide complementary features in terms of coverage, capacity and mobility support. These different networks will work together using vertical handover techniques and hence understanding how well these mechanisms perform is a significant issue. In this thesis, these networks are modelled to yield performance results such as mean queue lengths and blocking probabilities over a range of different conditions. The results are then analysed using network constraints to yield operational graphs based on handover probabilities to different networks. Firstly, individual networks with horizontal handover are analysed using performability techniques. The thesis moves on to look at vertical handovers between cellular networks using pure performance models. Then the integration of cellular networks and WLAN is considered. While analysing these results it became clear that the common models that were being used were subjected to handover hysteresis resulting from feedback loops in the model. A new analytical model was developed which addressed this issue but was shown to be problematic in developing state probabilities for more complicated scenarios. Guard channels analysis, which is normally used to give priority to handover traffic in mobile networks, was employed as a practical solution to the observed handover hysteresis. Overall, using different analytical techniques as well as simulation, the results of this work form an important part in the design and development of future mobile systems