Mobile Agents for Mobile Tourists: A User Evaluation of Gulliver's Genie

How mobile computing applications and services may be best designed, implemented and deployed remains the subject of much research. One alternative approach to developing software for mobile users that is receiving increasing attention from the research community is that of one based on intelligent agents. Recent advances in mobile computing technology have made such an approach feasible. We present an overview of the design and implementation of an archetypical mobile computing application, namely that of an electronic tourist guide. This guide is unique in that it comprises a suite of intelligent agents that conform to the strong intentional stance. However, the focus of this paper is primarily concerned with the results of detailed user evaluations conducted on this system. Within the literature, comprehensive evaluations of mobile context-sensitive systems are sparse and therefore, this paper seeks, in part, to address this deficiency

Context Aware Computing for The Internet of Things: A Survey

As we are moving towards the Internet of Things (IoT), the number of sensors deployed around the world is growing at a rapid pace. Market research has shown a significant growth of sensor deployments over the past decade and has predicted a significant increment of the growth rate in the future. These sensors continuously generate enormous amounts of data. However, in order to add value to raw sensor data we need to understand it. Collection, modelling, reasoning, and distribution of context in relation to sensor data plays critical role in this challenge. Context-aware computing has proven to be successful in understanding sensor data. In this paper, we survey context awareness from an IoT perspective. We present the necessary background by introducing the IoT paradigm and context-aware fundamentals at the beginning. Then we provide an in-depth analysis of context life cycle. We evaluate a subset of projects (50) which represent the majority of research and commercial solutions proposed in the field of context-aware computing conducted over the last decade (2001-2011) based on our own taxonomy. Finally, based on our evaluation, we highlight the lessons to be learnt from the past and some possible directions for future research. The survey addresses a broad range of techniques, methods, models, functionalities, systems, applications, and middleware solutions related to context awareness and IoT. Our goal is not only to analyse, compare and consolidate past research work but also to appreciate their findings and discuss their applicability towards the IoT.Comment: IEEE Communications Surveys & Tutorials Journal, 201

Innovative energy-efficient wireless sensor network applications and MAC sub-layer protocols employing RTS-CTS with packet concatenation

of energy-efficiency as well as the number of available applications. As a consequence there are challenges that need to be tackled for the future generation of WSNs. The research work from this Ph.D. thesis has involved the actual development of innovative WSN applications contributing to different research projects. In the Smart-Clothing project contributions have been given in the development of a Wireless Body Area Network (WBAN) to monitor the foetal movements of a pregnant woman in the last four weeks of pregnancy. The creation of an automatic wireless measurement system for remotely monitoring concrete structures was an contribution for the INSYSM project. This was accomplished by using an IEEE 802.15.4 network enabling for remotely monitoring the temperature and humidity within civil engineering structures. In the framework of the PROENEGY-WSN project contributions have been given in the identification the spectrum opportunities for Radio Frequency (RF) energy harvesting through power density measurements from 350 MHz to 3 GHz. The design of the circuits to harvest RF energy and the requirements needed for creating a WBAN with electromagnetic energy harvesting and Cognitive Radio (CR) capabilities have also been addressed. A performance evaluation of the state-of-the art of the hardware WSN platforms has also been addressed. This is explained by the fact that, even by using optimized Medium Access Control (MAC) protocols, if the WSNs platforms do not allow for minimizing the energy consumption in the idle and sleeping states, energy efficiency and long network lifetime will not be achieved. The research also involved the development of new innovative mechanisms that tries and solves overhead, one of the fundamental reasons for the IEEE 802.15.4 standard MAC inefficiency. In particular, this Ph.D. thesis proposes an IEEE 802.15.4 MAC layer performance enhancement by employing RTS/CTS combined with packet concatenation. The results have shown that the use of the RTS/CTS mechanism improves channel efficiency by decreasing the deferral time before transmitting a data packet. In addition, the Sensor Block Acknowledgment MAC (SBACK-MAC) protocol has been proposed that allows the aggregation of several acknowledgment responses in one special Block Acknowledgment (BACK) Response packet. Two different solutions are considered. The first one considers the SBACK-MAC protocol in the presence of BACK Request (concatenation) while the second one considers the SBACK-MAC in the absence of BACK Request (piggyback). The proposed solutions address a distributed scenario with single-destination and single-rate frame aggregation. The throughput and delay performance is mathematically derived under both ideal conditions (a channel environment with no transmission errors) and non ideal conditions (a channel environment with transmission errors). An analytical model is proposed, capable of taking into account the retransmission delays and the maximum number of backoff stages. The simulation results successfully validate our analytical model. For more than 7 TX (aggregated packets) all the MAC sub-layer protocols employing RTS/CTS with packet concatenation allows for the optimization of channel use in WSNs, v8-48 % improvement in the maximum average throughput and minimum average delay, and decrease energy consumption

Hierarchical Swarm Robotics

Distributed computing is becoming more and more prevalent in engineering today. Swarm robotics is simply an extension of that, not only dividing the computing power, but also the physical capabilities. This project served as a proof of concept investigation into the feasibility and potential effectiveness of a hierarchical swarm topology (HST), which better mimics the organization of many societal structures. This goal was approached by designing a three-tier robotic swarm as well as a specialized abstract coverage algorithm designed to map an unknown area. Experiments were conducted by modifying various parameters of an HST including the number of tiers and robots per tier. Results supported the original hypothesis that by adding robots, overall runtime and individual workload is reduced

Tecnologias IoT para pastoreio e controlo de postura animal

The unwanted and adverse weeds that are constantly growing in vineyards, force wine producers to repeatedly remove them through the use of mechanical and chemical methods. These methods include machinery such as plows and brushcutters, and chemicals as herbicides to remove and prevent the growth of weeds both in the inter-row and under-vine areas. Nonetheless, such methods are considered very aggressive for vines, and, in the second case, harmful for the public health, since chemicals may remain in the environment and hence contaminate water lines. Moreover, such processes have to be repeated over the year, making it extremely expensive and toilsome. Using animals, usually ovines, is an ancient practice used around the world. Animals, grazing in vineyards, feed from the unwanted weeds and fertilize the soil, in an inexpensive, ecological and sustainable way. However, sheep may be dangerous to vines since they tend to feed on grapes and on the lower branches of the vines, which causes enormous production losses. To overcome that issue, sheep were traditionally used to weed vineyards only before the beginning of the growth cycle of grapevines, thus still requiring the use of mechanical and/or chemical methods during the remainder of the production cycle. To mitigate the problems above, a new technological solution was investigated under the scope of the SheepIT project and developed in the scope of this thesis. The system monitors sheep during grazing periods on vineyards and implements a posture control mechanism to instruct them to feed only from the undesired weeds. This mechanism is based on an IoT architecture, being designed to be compact and energy efficient, allowing it to be carried by sheep while attaining an autonomy of weeks. In this context, the thesis herein sustained states that it is possible to design an IoT-based system capable of monitoring and conditioning sheep’s posture, enabling a safe weeding process in vineyards. Moreover, we support such thesis in three main pillars that match the main contributions of this work and that are duly explored and validated, namely: the IoT architecture design and required communications, a posture control mechanism and the support for a low-cost and low-power localization mechanism. The system architecture is validated mainly in simulation context while the posture control mechanism is validated both in simulations and field experiments. Furthermore, we demonstrate the feasibility of the system and the contribution of this work towards the first commercial version of the system.O constante crescimento de ervas infestantes obriga os produtores a manter um processo contínuo de remoção das mesmas com recurso a mecanismos mecânicos e/ou químicos. Entre os mais populares, destacam-se o uso de arados e roçadores no primeiro grupo, e o uso de herbicidas no segundo grupo. No entanto, estes mecanismos são considerados agressivos para as videiras, assim como no segundo caso perigosos para a saúde pública, visto que os químicos podem permanecer no ambiente, contaminando frutos e linhas de água. Adicionalmente, estes processos são caros e exigem mão de obra que escasseia nos dias de hoje, agravado pela necessidade destes processos necessitarem de serem repetidos mais do que uma vez ao longo do ano. O uso de animais, particularmente ovelhas, para controlar o crescimento de infestantes é uma prática ancestral usada em todo o mundo. As ovelhas, enquanto pastam, controlam o crescimento das ervas infestantes, ao mesmo tempo que fertilizam o solo de forma gratuita, ecológica e sustentável. Não obstante, este método foi sendo abandonado visto que os animais também se alimentam da rama, rebentos e frutos da videira, provocando naturais estragos e prejuízos produtivos. Para mitigar este problema, uma nova solução baseada em tecnologias de Internet das Coisas é proposta no âmbito do projeto SheepIT, cuja espinha dorsal foi construída no âmbito desta tese. O sistema monitoriza as ovelhas enquanto estas pastoreiam nas vinhas, e implementam um mecanismo de controlo de postura que condiciona o seu comportamento de forma a que se alimentem apenas das ervas infestantes. O sistema foi incorporado numa infraestrutura de Internet das Coisas com comunicações sem fios de baixo consumo para recolha de dados e que permite semanas de autonomia, mantendo os dispositivos com um tamanho adequado aos animais. Neste contexto, a tese suportada neste trabalho defende que é possível projetar uma sistema baseado em tecnologias de Internet das Coisas, capaz de monitorizar e condicionar a postura de ovelhas, permitindo que estas pastem em vinhas sem comprometer as videiras e as uvas. A tese é suportada em três pilares fundamentais que se refletem nos principais contributos do trabalho, particularmente: a arquitetura do sistema e respetivo sistema de comunicações; o mecanismo de controlo de postura; e o suporte para implementação de um sistema de localização de baixo custo e baixo consumo energético. A arquitetura é validada em contexto de simulação, e o mecanismo de controlo de postura em contexto de simulação e de experiências em campo. É também demonstrado o funcionamento do sistema e o contributo deste trabalho para a conceção da primeira versão comercial do sistema.Programa Doutoral em Informátic

New Waves of IoT Technologies Research – Transcending Intelligence and Senses at the Edge to Create Multi Experience Environments

The next wave of Internet of Things (IoT) and Industrial Internet of Things (IIoT) brings new technological developments that incorporate radical advances in Artificial Intelligence (AI), edge computing processing, new sensing capabilities, more security protection and autonomous functions accelerating progress towards the ability for IoT systems to self-develop, self-maintain and self-optimise. The emergence of hyper autonomous IoT applications with enhanced sensing, distributed intelligence, edge processing and connectivity, combined with human augmentation, has the potential to power the transformation and optimisation of industrial sectors and to change the innovation landscape. This chapter is reviewing the most recent advances in the next wave of the IoT by looking not only at the technology enabling the IoT but also at the platforms and smart data aspects that will bring intelligence, sustainability, dependability, autonomy, and will support human-centric solutions.acceptedVersio

A mobile based control system for smart homes

A Smart Home Control System can provide a secure home, convenience, comfort, and interactivity of life in a particular home. The system can enable the automatic controlling of a house via a Smart Phone. These systems are becoming vital and widely used in homes to improve conditions of life. Most commercial home automation systems are expensive and their maintenance would require experts who understand the underlying implementation of the systems. This study developed a mobile-based home automation system prototype. The system was developed using the waterfall model methodology. To evaluate the developed system, the study used a simulation method. Ten trials were conducted to determine the performance of the implemented system. The mean time to failure was used to evaluate the system’ reliability. The system’s performance analysis revealed that the developed system performed better than the two other approaches; the Bluetooth and ZigBee. The developed system showed a 0 percent error, while the Bluetooth had 8 percent error and ZigBee 6 percent error. The reliability results showed the average lifespan of assets in the system before they could fail. Knowing the lifespan of an asset before it fails can help in reducing downtime of the system by planning or scheduling maintenance and develop an improved maintenance strategy.Thesis (MSc) -- Faculty of Science and Agriculture, 202

Effectiveness of OPC for systems integration in the process control information architecture

A Process is defined as the progression to some particular end or objective through a logical and orderly sequence of events. Various devices (e.g., actuators, limit switches, motors, sensors, etc.) play a significant role in making sure that the process attains its objective (e.g., maintaining the furnace temperature within an acceptable limit). To do these things effectively, manufacturers need to access data from the plant floor or devices and integrate those into their control applications, which maybe one of the off the shelf tools such as Supervisory Control and Data Acquisition (SCADA), Distributed Control System (DCS), or Programmable Logic Controllers (PLC). A number of vendors have devised their own Data Acquisition Networks or Process Control Architectures (e.g., PROFIBUS, DEVICENET, INTERBUS, ETHERNET I/P, etc.) that claim to be open to or interoperable with a number of third party devices or products that make process data available to the Process or Business Management level. In reality this is far from what it is claimed to be. Due to the problem of interoperability, a manufacturer is forced to be bound, either with the solutions provided by a single vendor or with the writing of a driver for each hardware device that is accessed by a process application. Today\u27s manufacturers are looking for advanced distributed object technologies that allow for seamless exchange of information across plant networks as a means of integrating the islands of automation that exist in their manufacturing operations. OLE for Process Control (OPC) works to significantly reduce the time, cost, and effort required in writing custom interfaces for hundreds of different intelligent devices and networks in use today. The objective of this thesis is to explore the OLE for Process Control (OPC) technology in depth by highlighting its need in industry and by using the OPC technology in an application in which data from a process controlled by Siemens Simatic S7 PLC are shared with a client application running in LabVTEW6i

A mobile based control system for smart homes

A Smart Home Control System can provide a secure home, convenience, comfort, and interactivity of life in a particular home. The system can enable the automatic controlling of a house via a Smart Phone. These systems are becoming vital and widely used in homes to improve conditions of life. Most commercial home automation systems are expensive and their maintenance would require experts who understand the underlying implementation of the systems. This study developed a mobile-based home automation system prototype. The system was developed using the waterfall model methodology. To evaluate the developed system, the study used a simulation method. Ten trials were conducted to determine the performance of the implemented system. The mean time to failure was used to evaluate the system’ reliability. The system’s performance analysis revealed that the developed system performed better than the two other approaches; the Bluetooth and ZigBee. The developed system showed a 0 percent error, while the Bluetooth had 8 percent error and ZigBee 6 percent error. The reliability results showed the average lifespan of assets in the system before they could fail. Knowing the lifespan of an asset before it fails can help in reducing downtime of the system by planning or scheduling maintenance and develop an improved maintenance strategy.Thesis (MSc) -- Faculty of Science and Agriculture, 202