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New satellite-based techniques open up new horizons to researchers and local communities. Concurrently, however, requirements and expectations with regard to satel-lite-based remote sensing products are increasingly higher. By relying on satellite-derived information, environmental observations can cover areas of a few to several metres resolution. Here we are dealing with free-of-charge and generally available sources of satellite-based information. The Piaśnica River mouth area was selected as an observation site representing a highly dynamic morphological transect. The paper compares products of cloud cover detection, supplied with data and available in the Copernicus database for a local area in the coastal zone of the Baltic Sea. The absolute difference did not exceed 5%, which confirms a high efficiency of the solutions offered. More than 96% of the clouded area determined for the Sentinel-2/MSI (Multispectral Instrument) was correctly identified when compared with supervised observations. The rate was lower (92%) for the Sentinel-3/OLCI (Ocean and Land Colour Instrument). It was eventually concluded that, at the local level, successful observations can be conducted using the cloud cover map supplied with the satellite data. At the same time, the analyses presented do not rule out further efforts to, e.g., increase the accuracy and speed of the analyses. [ABSTRACT FROM AUTHOR]

A very simple algorithm with which to assess cloudiness over the Baltic Sea has been developed. The algorithm involves analysis of cloud longwave emissivity, supplemented with available information on shortwave emissions. The simple classification method is based on the split-window technique and compares a signal recorded in the neighbouring spectral bands with results of cloud-free atmosphere modelling. The algorithm was tested using data from the SEVIRI (Spinning Enhanced Visible and InfraRed Imager) satellite radiometer, but the method can be easily implemented for other data sources. Compatibility with instant shipborne radiation measurements was obtained. The effectiveness of the comparison was determined from the Hanssen–Kuiper score. The CM SAF (Satellite Application Facility on Climate Monitoring) data comparison shows that the system correctly classified areas in 88%, the satellite map accuracy was 46% with a 54% overvaluation error. The accuracy of the detection system was 44%, and the underestimation error was 56%. The comparison of modelling results showed 71% of correctly classified areas, the accuracy of the satellite map was 35%, and the repricing error was 65%. The accuracy of the detection system was 36%, and the underestimation error was 64%. The concordance of satellite measurements (Cohen's kappa coefficient) was at a level of 98% and 99% between the satellite and model. Statistically, the analysis is based on the results of measurements for the Baltic Sea basin in 2015. The obtained data on the monthly cloudiness was compared with the operational, model and lidar data. A difference between the solution proposed and the approaches derived from prognostic models is demonstrated. The regional scale solution is shown to be a better representation of the true state of the atmosphere, compared to global-scale models. The results obtained show cloudiness assessments to differ depending on the model applied (CM SAF, UMPL – Unifed Model for Poland). The average annual cloudiness of the Baltic Sea is around 58.5%. It is a repeatable value by other solutions based on various methods and sources (MODIS – Moderate Resolution Imaging Spectroradiometer), including lidar ones (CALIPSO – Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation). In addition, a potential for applying the regional cloudiness assessment to estimate the top-down components of the radiation budget is illustrated. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of power consumption in the context of AR applications on the HoloLens 2. As an ablation study, the research systematically dissects various aspects, shedding light on both hardware and software components. The power consumption was examined in diverse scenarios, ranging from the device at idle to running AR applications of increasing complexity. Overall, the study provides insights into the power management aspects associated with Hololens 2 AR devices and applications, offering cues for optimizing energy efficiency and enhancing the user experience. The findings confirm that display-related factors, such as the screen brightness and content complexity, significantly impact power consumption. However, the results reveal that power usage does not scale linearly with the number of objects in an AR scene due to overhead factors and object occlusion. Furthermore, usage scenarios such as lighting conditions and large/minor user motions are analyzed. Moreover, the influence of different development platforms, Unity and Unreal, on power consumption is discussed, highlighting their respective contributions to energy usage. These findings might be useful for researchers, developers, and users of AR technology. [ABSTRACT FROM AUTHOR]

The search for clouds in satellite images is a challenging subject which still attracts a lot of attention due to the amount and quality of data, which is growing at a tremendous pace, the development of satellite techniques and methods, inexpensive equipment, and automation of satellite imaging processes. This paper presents a new approach to the assessment of cloudiness based on the use of the theory of moments with invariants. The values of moments with invariants, determined on the basis of the available cloudiness maps, create a new, valuable set of data, which are the geometrical parameters of the scene representing the cloud cover. In further research, the obtained data sets will be used in machine learning methods, deep machine learning methods, etc. The method is used for different conditions, including different angular positions of the Sun and time periods. The effectiveness of the method is checked on the basis of comparing the entropy results of the input maps after subtracting clouds masked by various methods. The obtained results additionally indicate the potential of the moments method as a support for the existing methods of estimating cloudiness over the sea surface. [ABSTRACT FROM AUTHOR]

A simple detection method was proposed to increase the efficiency of automatic classification of a satellite image cell (clear/cloudy). A method is described on the basis of the Advanced Very High Resolution Radiometer (AVHRR) data, with a focus on highly active and highly reflecting targets (i.e., the Baltic Sea). Radiation input conditions and the dynamic threshold were used to reduce geometric influences of any daily scene supplied by the NOAA-17 and NOAA-18 platforms. They were carried out from statistic and histogram sequences of albedo and temperature maps. The presented approach is intended to primarily serve the activation of a nonsupervised system for oceanographic analyses (mainly SST), based on an accurate cloud mask. [ABSTRACT FROM AUTHOR]

Abstract: The coefficients that characterize the simultaneous transports of mass, heat, solute and current through compact clays are experimentally and theoretically determined. The role of a characteristic length scale that can be derived from conductivity and permeability is illustrated for the electrokinetic coefficients. The macroscopic Soret coefficient in clays was found five times larger than in the free fluid, presumably because of extra couplings with electrical phenomena. To cite this article: M. Paszkuta et al., C. R. Geoscience 338 (2006). [Copyright &y& Elsevier]

This paper presents a theoretical study into the use of optical systems for quantum computation. The study results pertain to quantum sampling and quantum communication and provide a basis for further research and the development of a physical implementation. We propose an optical superstructure that can implement specific computation processes and algorithms. The superstructure is composed of nonlinear optical units, such as beta barium borate crystals. The units are positioned in series, powered by a pulse laser pump, and culminate in a beam splitter that generates the output state of a number of entangled photon pairs. Computation is achieved by entanglement propagation via beam splitters and adjustable phase shifters, which set related parameters. Demonstrating a two-component case, we show how a series of cosine-based components can be implemented. The obtained results open a broad front for future research. Future work should investigate the construction of a quantum optimizer using quantum sampling methods and also investigate high-precision temporal voltage measurement, which is a key procedure for the construction of high-fidelity devices. [ABSTRACT FROM AUTHOR]

This work is focused on the preliminary stage of the 3D drone tracking challenge, namely the precise detection of drones on images obtained from a synchronized multi-camera system. The YOLOv5 deep network with different input resolutions is trained and tested on the basis of real, multimodal data containing synchronized video sequences and precise motion capture data as a ground truth reference. The bounding boxes are determined based on the 3D position and orientation of an asymmetric cross attached to the top of the tracked object with known translation to the object's center. The arms of the cross are identified by the markers registered by motion capture acquisition. Besides the classical mean average precision (mAP), a measure more adequate in the evaluation of detection performance in 3D tracking is proposed, namely the average distance between the centroids of matched references and detected drones, including false positive and false negative ratios. Moreover, the videos generated in the AirSim simulation platform were taken into account in both the training and testing stages. [ABSTRACT FROM AUTHOR]

Recently developed system for assessment of radiation budget for the Baltic Sea has been presented and verified. The system utilizes data from various sources: satellite, model and in situ measurements. It has been developed within the SatBałtyk project (Satellite Monitoring of the Baltic Sea Environment - www.satbaltyk.eu) where the energy radiation budget is one of the key element. The SatBałtyk system generates daily maps of the all components of radiation budget on every day basis. We show the scheme of making daily maps, applied algorithms and empirical data collection within the system. An empirical verification of the system has been carried out based on empirical data collected on the oil rig placed on the Baltic Sea. This verification concerned all the components of the surface radiation budget. The average daily NET products are estimated with statistical error ca. 13 Wm-2. The biggest absolute statistical error is for LWd component and equals 14 Wm-2. The relative error in relation to the average annual values for whole Baltic is the biggest for SWu and reaches 25%. All estimated components have correlation coefficient above 0.91. [ABSTRACT FROM AUTHOR]

The paper describes a scalable, wearable multi-sensor system for motion capture based on inertial measurement units (IMUs). Such a unit is composed of accelerometer, gyroscope and magnetometer. The final quality of an obtained motion arises from all the individual parts of the described system. The proposed system is a sequence of the following stages: sensor data acquisition, sensor orientation estimation, system calibration, pose estimation and data visualisation. The construction of the system’s architecture with the dataflow programming paradigm makes it easy to add, remove and replace the data processing steps. The modular architecture of the system allows an effortless introduction of a new sensor orientation estimation algorithms. The original contribution of the paper is the design study of the individual components used in the motion capture system. The two key steps of the system design are explored in this paper: the evaluation of sensors and algorithms for the orientation estimation. The three chosen algorithms have been implemented and investigated as part of the experiment. Due to the fact that the selection of the sensor has a significant impact on the final result, the sensor evaluation process is also explained and tested. The experimental results confirmed that the choice of sensor and orientation estimation algorithm affect the quality of the final results. [ABSTRACT FROM AUTHOR]