The advent of Internet of Things has propelled the agricultural domain through the integration of sensory devices, capable of monitoring and wirelessly propagating information to producers; thus, they employ Wireless Sensor Networks (WSNs). These WSNs allow real time monitoring, enabling intelligent decision-making to maximize yields and minimize cost. Designing and deploying a WSN is a challenging and multivariate task, dependent on the considered environment. For example, a need for network synchronization arises in such networks to correlate acquired measurements. This work focuses on the design and installation of a WSN that is capable of facilitating the sensing aspects of smart and precision agriculture applications. A system is designed and implemented to address specific design requirements that are brought about by the considered environment. A simple synchronization scheme is described to provide time-correlated measurements using the sink node’s clock as reference. The proposed system was installed on an olive grove to assess its effectiveness in providing a low-cost system, capable of acquiring synchronized measurements. The obtained results indicate the system’s overall effectiveness, revealing a small but expected difference in the acquired measurements’ time correlation, caused mostly by serial transmission delays, while yielding a plethora of relevant environmental conditions.

Virtual tours in museums are an ideal solution for those that are not able to visit a museum or those who want to have a small taste of what is presented in the museum before their visit. However, these tours often encounter severe problems while users interact with them. In order to check the status of virtual tours of museums, we present the implementation of an evaluation experiment that uses a combination of two multi-criteria decision making theories, namely the analytic hierarchy process (AHP) and the fuzzy technique for order of preference by similarity to ideal solution (TOPSIS). AHP has been used for the estimation of the weights of the heuristics and fuzzy TOPSIS has been used for the evaluation of virtual tours of museums. This paper presents the exact steps that have to be followed in order to implement such an experiment and run an example experiment for virtual tours of Italian museums.

Immersive technologies (Virtual, Augmented, and Mixed Reality) are widely used in cultural heritage for communication, enhancing the visiting experience, and improving learning and understanding. Immersive technologies have found their way into museums and other cultural spaces in various forms and shapes. This work aims to recognize the main forms of immersive technologies and applications in museums and other cultural spaces and provide information on the employed methods, technologies, equipment, and software solutions by conducting a systematic literature review aligned with the PRISMA guidelines. The analyzed literature was collected through a focused search in scientific databases (Scopus, ACM, and IEEE). The relevance to the subject was assessed based on the main technological focus (VR/AR/MR or XR) and the employed technologies. Methods and approaches for realizing their applications were studied and discussed. Thirteen articles were found to meet the selection criteria, of which two focus on VR, six are on AR, two are on Audio-AR, and three are on MR. The results showed that Augmented Reality solutions are preferred for on-site use; Mixed Reality applications started to emerge as Mixed Reality hardware technology became available and Virtual Reality despite being criticized for isolating visitors. The findings cover the existing gap in recent literature and can reveal a set of good practices and innovative ideas for future applications.

Structural health monitoring (SHM) in historical buildings can be achieved through systems that rely on Wireless Sensor Networks (WSNs). Such systems have the ability to acquire information fast and reliably, making them ideal for SHM applications. Historical buildings, having been exposed to the wear of time, are especially sensitive to any kind of intervention. As a result, keeping them as intact as possible is a critical factor for their integrity. In the current work, a low-cost WSN system and a synchronization algorithm are developed in order to be employed for SHM of historical buildings. The synchronization of WSN-based SHM systems is critical for the collection of accurate information describing the building’s condition. The effectiveness of the assumed hardware and the synchronization algorithm were evaluated with two experiments. The first took place under laboratory conditions and its results showcase the algorithm’s accuracy of synchronization. The second experiment was conducted in a real-world environment. For that purpose, the Ionian Campus Testbed was chosen since it comprises buildings that are more than 200 years old. These buildings are appropriate since they were built with thick stone walls which help determine the system’s effectiveness under such conditions. The results derived from the second experiment showcase the effects of the packet transmission collision avoidance mechanism utilized by the assumed hardware. Finally, an estimation of the average clock skew required for accurate information gathering is derived, based on the materials comprising a historical building.

With the rapid increase of vehicles in use worldwide, the need for efficient traffic monitoring systems has arisen. This work proposes a low-cost vehicular traffic monitoring system using IoT devices and fog computing. The system is based on a three-tiered architecture which is composed of (i) the mobile tracking system that records the positions of the vehicles using GPS technologies; (ii) the information gathering system which gathers all the data collected by the mobile tracking system; and (iii) the fog devices that process the data collected and extract the information needed. The system is tested in the town of Corfu during a period of increased tourism when the traffic is considered to be relatively dense. The mobile tracking system devices are placed on taxis and with the help of professional taxi drivers the accuracy of the data collected is evaluated. The system is able to record the movement of the vehicles accurately using its own independent data. The results can be remotely accessed by utilizing fog and cloud computing infrastructure established to process the data and upload it on a server. The system is used to give a better understanding of the speed variance in the center of the town during different dates and hours. In conclusion the system presented in this study can be utilized to monitor the traffic and provide vital information about its behavior in relation to time.

In recent years, cultural projects utilizing digital applications and immersive technologies (VR, AR, MR) have grown significantly, enhancing cultural heritage experiences. Research emphasizes the importance of usability, user experience, and accessibility, yet holistic approaches remain underexplored and many projects fail to reach their audience. This article aims to bridge this gap by presenting a complete workflow including systematic requirements analysis, design guidelines, and development solutions based on knowledge extracted from previous relevant projects. The article focuses on virtual museums covering key challenges including compatibility, accessibility, usability, navigation, interaction, computational performance and graphics quality, and provides a design schema for integrating virtual museums into such projects. Following this approach, a number of applications are presented. Their performance with respect to the aforementioned key challenges is evaluated. Users are invited to assess them, providing positive results. To assess the virtual museum’s ability to attract a broader audience beyond the usual target group, a group of underserved minorities are also invited to use and evaluate it, generating encouraging outcomes. Concluding, results show that the presented workflow succeeds in yielding high-quality applications for cultural heritage communication and attraction of wider audiences, and outlines directions for further improvements in digitized heritage applications.