Teodora Sanislav

Bio: Teodora Sanislav is an academic researcher from Technical University of Cluj-Napoca. The author has contributed to research in topics: Cyber-physical system & Dependability. The author has an hindex of 10, co-authored 30 publications receiving 553 citations.

Analysis of Three IoT-Based Wireless Sensors for Environmental Monitoring

Abstract: The recent changes in climate have increased the importance of environmental monitoring, making it a topical and highly active research area. This field is based on remote sensing and on wireless sensor networks for gathering data about the environment. Recent advancements, such as the vision of the Internet of Things (IoT), the cloud computing model, and cyber-physical systems, provide support for the transmission and management of huge amounts of data regarding the trends observed in environmental parameters. In this context, the current work presents three different IoT-based wireless sensors for environmental and ambient monitoring: one employing User Datagram Protocol (UDP)-based Wi-Fi communication, one communicating through Wi-Fi and Hypertext Transfer Protocol (HTTP), and a third one using Bluetooth Smart. All of the presented systems provide the possibility of recording data at remote locations and of visualizing them from every device with an Internet connection, enabling the monitoring of geographically large areas. The development details of these systems are described, along with the major differences and similarities between them. The feasibility of the three developed systems for implementing monitoring applications, taking into account their energy autonomy, ease of use, solution complexity, and Internet connectivity facility, was analyzed, and revealed that they make good candidates for IoT-based solutions.

Cyber-Physical Systems - Concept, Challenges and Research Areas

Abstract: Cyber-Physical Systems (CPSs) represent an emerging research area that has attracted the attention of many researchers. Starting from the definition of CPS, the paper discusses the need for these systems implementation in various application domains and the research challenges for defining an appropriate formalism that represent more than networking and information technology - the information and knowledge will be integrated into physical objects. As CPSs are expected to play a major role in the design and development of future engineering systems, a short state of the art regarding the main CPS research areas (generic architecture, design principles, modeling, dependability, and implementation) ends the paper.

A Cyber-Physical System for Environmental Monitoring

Abstract: This paper presents the development of a cyber-physical system that monitors the environmental conditions or the ambient conditions in indoor spaces at remote locations. The communication between the system’s components is performed using the existent wireless infrastructure based on the IEEE 802.11 b/g standards. The resulted solution provides the possibility of logging measurements from locations all over the world and of visualizing and analyzing the gathered data from any device connected to the Internet. This work encompasses the complete solution, a cyber-physical system, starting from the physical level, consisting of sensors and the communication protocol, and reaching data management and storage at the cyber level. The experimental results show that the proposed system represents a viable and straightforward solution for environmental and ambient monitoring applications.

Energy Harvesting Techniques for Internet of Things (IoT)

Abstract: The rapid growth of the Internet of Things (IoT) has accelerated strong interests in the development of low-power wireless sensors. Today, wireless sensors are integrated within IoT systems to gather information in a reliable and practical manner to monitor processes and control activities in areas such as transportation, energy, civil infrastructure, smart buildings, environment monitoring, healthcare, defense, manufacturing, and production. The long-term and self-sustainable operation of these IoT devices must be considered early on when they are designed and implemented. Traditionally, wireless sensors have often been powered by batteries, which, despite allowing low overall system costs, can negatively impact the lifespan and the performance of the entire network they are used in. Energy Harvesting (EH) technology is a promising environment-friendly solution that extends the lifetime of these sensors, and, in some cases completely replaces the use of battery power. In addition, energy harvesting offers economic and practical advantages through the optimal use of energy, and the provisioning of lower network maintenance costs. We review recent advances in energy harvesting techniques for IoT. We demonstrate two energy harvesting techniques using case studies. Finally, we discuss some future research challenges that must be addressed to enable the large-scale deployment of energy harvesting solutions for IoT environments.

About dependability in cyber-physical systems

Abstract: This paper presents definitions characterizing the concepts regarding cyber-physical systems and dependability. Cyber-physical systems incorporate computing, communication and storage capabilities with monitoring and/or control of entities in the physical world in a dependably, securely, efficiently and real-time way. The challenges of cyber-physical system research are concerning: real-time system abstractions; robustness, safety and security; QoS composition; and nor least dependability. Dependability is first introduced as a global concept that subsumes the usual attributes of reliability, availability, safety, integrity and maintainability. The paper aims to define research challenges to achieve the dependability in cyber-physical hydropower systems. The significant challenge of the dependability in cyber-physical hydropower systems is evaluation of the system behavior in terms of interdependencies between cyber and physical components of the system.

Design Techniques and Applications of Cyberphysical Systems: A Survey

Abstract: Cyberphysical systems (CPSs) are new class of engineered systems that offer close interaction between cyber and physical components. The field of CPS has been identified as a key area of research, and CPSs are expected to play a major role in the design and development of future systems. In this paper, we survey recent advancements made in the development and applications of CPSs. We classify the existing research work based on their characteristics and identify the future challenges. We also discuss the examples of prototypes of CPSs. The aim of this survey is to enable researchers and system designers to get insights into the working and applications of CPSs and motivate them to propose novel solutions for making wide-scale adoption of CPS a tangible reality.

Energy-Efficient Wireless Sensor Networks for Precision Agriculture: A Review.

Abstract: Wireless sensor networks (WSNs) can be used in agriculture to provide farmers with a large amount of information. Precision agriculture (PA) is a management strategy that employs information technology to improve quality and production. Utilizing wireless sensor technologies and management tools can lead to a highly effective, green agriculture. Based on PA management, the same routine to a crop regardless of site environments can be avoided. From several perspectives, field management can improve PA, including the provision of adequate nutrients for crops and the wastage of pesticides for the effective control of weeds, pests, and diseases. This review outlines the recent applications of WSNs in agriculture research as well as classifies and compares various wireless communication protocols, the taxonomy of energy-efficient and energy harvesting techniques for WSNs that can be used in agricultural monitoring systems, and comparison between early research works on agriculture-based WSNs. The challenges and limitations of WSNs in the agricultural domain are explored, and several power reduction and agricultural management techniques for long-term monitoring are highlighted. These approaches may also increase the number of opportunities for processing Internet of Things (IoT) data.

Monitoring of Large-Area IoT Sensors Using a LoRa Wireless Mesh Network System: Design and Evaluation

Abstract: Although many techniques exist to transfer data from the widely distributed sensors that make up the Internet of Things (IoT) (e.g., using 3G/4G networks or cables), these methods are associated with prohibitively high costs, making them impractical for real-life applications. Recently, several emerging wireless technologies have been proposed to provide long-range communication for IoT sensors. Among these, LoRa has been examined for long-range performance. Although LoRa shows good performance for long-range transmission in the countryside, its radio signals can be attenuated over distance, and buildings, trees, and other radio signal sources may interfere with the signals. Our observations show that in urban areas, LoRa requires dense deployment of LoRa gateways (GWs) to ensure that indoor LoRa devices can successfully transfer data back to remote GWs. Wireless mesh networking is a solution for increasing communication range and packet delivery ratio (PDR) without the need to install additional GWs. This paper presents a LoRa mesh networking system for large-area monitoring of IoT applications. We deployed 19 LoRa mesh networking devices over an $800\,\,\text {m} \times 600$ m area on our university campus and installed a GW that collected data at 1-min intervals. The proposed LoRa mesh networking system achieved an average 88.49% PDR, whereas the star-network topology used by LoRa achieved only 58.7% under the same settings. To the best of our knowledge, this is the first academic study discussing LoRa mesh networking in detail and evaluating its performance via real experiments.