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The fusion of geomatic techniques with different accuracy and resolution has been used in recent years to applications of geometrical documentation for several archaeological sites. In this research article, the case of the Roman Baths of Amathus in Limassol, Cyprus was investigated.Aerial photogrammetry and Terrestrial Laser Scanning (TLS) techniques were used to produce the final product. The photogrammetric data were based on Post-Processed Kinematic (PPK) imagery while the TLS georeference was based on targets.The main research objective of this paper is to examine the reliability of PPK photogrammetric data without the use of Ground Control Points (GCPs) and how well they can be integrated with TLS data. Also, the two acquisition techniques were compared and indicated that 0.005 m Ground Sampling Distance (GSD) resolution aerial images and 0.0061/10 m resolution scans can be qualitatively fused.The research paper will present the entire methodology up to the generation of the final 3D photorealistic product. [ABSTRACT FROM AUTHOR]

Current advancements on photogrammetric software along with affordability and wide spreading of Unmanned Aerial Vehicles (UAV), allow for rapid, timely and accurate 3D modelling and mapping of small to medium sized areas. Although the importance and applications of large format aerial overlaps cameras and photographs in Digital Surface Model (DSM) production and LIDAR data is well documented in literature, this is not the case for UAV photography. Additionally, the main disadvantage of photogrammetry is the inability to map the dead ground (terrain), when we deal with areas that include vegetation. This paper assesses the use of nearinfrared imagery captured by small UAV platforms to automatically remove vegetation from Digital Surface Models (DSMs) and obtain a Digital Terrain Model (DTM). Two areas were tested, based on the availability of ground reference points, both under trees and among vegetation, as well as on terrain. In addition, RGB and near-infrared UAV photography was captured and processed using Structure from Motion (SfM) and Multi View Stereo (MVS) algorithms to generate DSMs and corresponding colour and NIR orthoimages with 0.2m and 0.25m as pixel size respectively for the two test sites. Moreover, orthophotos were used to eliminate the vegetation from the DSMs using NDVI index, thresholding and masking. Following that, different interpolation algorithms, according to the test sites, were applied to fill in the gaps and created DTMs. Finally, a statistic analysis was made using reference terrain points captured on field, both on dead ground and under vegetation to evaluate the accuracy of the whole process and assess the overall accuracy of the derived DTMs in contrast with the DSMs. [ABSTRACT FROM AUTHOR]

A fuzzy model was designed to characterize the quality of mandarin irrigation water. The model consisted of individual cascade submodels. This procedure simplifies the process, and on the other hand allows us to study the effect of individual variables in the final decision. Precisely, the effect of three irrigation water resources (Irrigators association water (IW), Reclaimed Water, and Transferred Water) were studied on the development of mandarin’s tree crop. The application of the model showed that the IW irrigation gives the best results. [ABSTRACT FROM PUBLISHER]

Photogrammetry is a valid alternative solution to linear variable differential transformer (LVDT) measurements in structural testing in laboratory conditions. Although the use of LVDTs boasts a high degree of accuracy, on the other hand it is limiting as it offers measurements between two points and it thus might be unable to capture localized deformations and strains over a bigger area of a structural specimen. In this aspect photogrammetry seems to offer certain advantages. Commercial solutions provide limited testing envelopes, while on the other hand, the wide range on new materials need more versatile techniques. Based on the need to develop an in-house photogrammetric toolbox to support several structural and material experiments in the department Advanced Pore Morphology (APM) aluminium foam specimens developed at Fraunhofer IFAM in Germany and cured at CUT, were tested under monotonic compressive load. Data acquisition, analysis and results, along with lessons learnt from the process are presented in this work. [ABSTRACT FROM AUTHOR]

We established a Mamdani fuzzy logic model to determine the effect of wastewater evapotranspiration on citrus cultivation. The model uses most influential variables of soil and leaves samples. Since the number of the input variables to the model is large, these variables were classified into five categories as follows: (i) soil macro-element concentration, (ii) soil essential elements concentration, (iii) soil electrochemical properties, (iv) leaves macro-elements concentration, and (v) leaves essential elements concentration. For simplification, the model was divided into seven submodels and one main model. The output of the main model considered the outputs of all submodels to the final decision. The model applied to a citrus orchard suggested the optimal wastewater irrigation rate at 125% of crop evapotranspiration. [ABSTRACT FROM PUBLISHER]

The very shallow marine basin of Puck Lagoon in the southern Baltic Sea, on the Northern coast of Poland, hosts valuable benthic habitats and cultural heritage sites. These include, among others, protected Zostera marina meadows, one of the Baltic's major medieval harbours, a ship graveyard, and likely other submerged features that are yet to be discovered. Prior to this project, no comprehensive high-resolution remote sensing data were available for this area. This article describes the first Digital Elevation Models (DEMs) derived from a combination of airborne bathymetric LiDAR, multibeam echosounder, airborne photogrammetry and satellite imagery. These datasets also include multibeam echosounder backscatter and LiDAR intensity, allowing determination of the character and properties of the seafloor. Combined, these datasets are a vital resource for assessing and understanding seafloor morphology, benthic habitats, cultural heritage, and submerged landscapes. Given the significance of Puck Lagoon's hydrographical, ecological, geological, and archaeological environs, the high-resolution bathymetry, acquired by our project, can provide the foundation for sustainable management and informed decision-making for this area of interest., (© 2024. The Author(s).)

The topic of underwater (UW) image colour correction and restoration has gained significant scientific interest in the last couple of decades. There are a vast number of disciplines, from marine biology to archaeology, that can and need to utilise the true information of the UW environment. Based on that, a significant number of scientists have contributed to the topic of UW image colour correction and restoration. In this paper, we try to make an unbiased and extensive review of some of the most significant contributions from the last 15 years. After considering the optical properties of water, as well as light propagation and haze that is caused by it, the focus is on the different methods that exist in the literature. The criteria for which most of them were designed, as well as the quality evaluation used to measure their effectiveness, are underlined.

This paper presents a combined subjective and objective evaluation of an application mixing interactive virtual reality (VR) experience with 360° storytelling. The hypothesis that the modern immersive archaeological VR application presenting cultural heritage from a submerged site would sustain high levels of presence, immersion, and general engagement was leveraged in the investigation of the user experience with both the subjective (questionnaires) and the objective (neurophysiological recording of the brain signals using electroencephalography (EEG)) evaluation methods. Participants rated the VR experience positively in the questionnaire scales for presence, immersion, and subjective judgement. High positive rating concerned also the psychological states linked to the experience (engagement, emotions, and the state of flow), and the experience was mostly free from difficulties linked to the accustomization to the VR technology (technology adoption to the head-mounted display and controllers, VR sickness). EEG results are in line with past studies examining brain responses to virtual experiences, while new results in the beta band suggest that EEG is a viable tool for future studies of presence and immersion in VR.

Underwater augmented reality is a very challenging task and amongst several issues, one of the most crucial aspects involves real-time tracking. Particles present in water combined with the uneven absorption of light decrease the visibility in the underwater environment. Dehazing methods are used in many areas to improve the quality of digital image data that is degraded by the influence of the environment. This paper describes the visibility conditions affecting underwater scenes and shows existing dehazing techniques that successfully improve the quality of underwater images. Four underwater dehazing methods are selected for evaluation of their capability of improving the success of square marker detection in underwater videos. Two reviewed methods represent approaches of image restoration: Multi-Scale Fusion, and Bright Channel Prior. Another two methods evaluated, the Automatic Color Enhancement and the Screened Poisson Equation, are methods of image enhancement. The evaluation uses diverse test data set to evaluate different environmental conditions. Results of the evaluation show an increased number of successful marker detections in videos pre-processed by dehazing algorithms and evaluate the performance of each compared method. The Screened Poisson method performs slightly better to other methods across various tested environments, while Bright Channel Prior and Automatic Color Enhancement shows similarly positive results., (Copyright © 2018 Žuži, Čejka, Bruno, Skarlatos and Liarokapis.)

A common practice in random noise measurements is to assume that the noise samples are normally distributed. Since the sound pressure level (Lp) is related with the sound energy by a non linear equation, the distribution of the two variables will be different. If one assumes that the probability density function (pdf) of Lp is normal, the pdf of noise energy is not and vice versa. A simple criterion based on statistical properties of sampled noise can be used for the determination of the kind of distribution of the measured noise. The case in which the noise energy emitted by the source, and the case in which the measured noise level is normally distributed are examined. For each case confidence intervals of the calculated equivalent level are calculated.

Noise pollution in most European and mainly Greek towns, is a major environmental problem. The annoyance caused by environmental noise is great and the use of a reliable descriptor of noise is important. This paper attempts to evaluate the noise fluctuations at an observation point by introducing a probabilistic model for the system environment-noise.The proposed model considers environmental noise as a stochastic signal neglecting the identity of noise sources as well as all other physical factors of the system. Regression methods were used to fit fluctuating noise levels to a trigonometric series. The use of "power spectrum" linearizes the problem and simplifies the method of regression in searching for the best model. A correcting term of L dn is proposed and the use of the model makes the calculation of the above mentioned term simple.