Preprints  

Low-cost sensors could fill gaps in existing observation networks. To ensure data quality, the quality of the factory calibration of a given sensor has to be evaluated, if the sensor is used out-of-the box. Here, the factory calibration of a widely used low-cost rain gauge type has been tested, both in the lab (66) and in the field (20). Results of the study suggest, that the calibration of this particular type should at least be checked for every sensor, before put into duty.

Thanks to technological developments, collecting seismic signals is hugely increasing. Unfortunately, having more data is subject to limited human capability of handling such data in reasonable time. That's why, in this paper, we propose to “transfer” the human experience into an artificial intelligence based system able to automatically distinguish seismometers collected data as “good” or “bad” using spectral diagram images.

We present the implementation of a VLF/LF network for searching earthquake electromagnetic precursors. The proposed system will deliver a steady stream of real-time amplitude and phase-measurements and a daily recording VLF/LF data set. A first implementation of the system was done in Graz, Austria, the second one will be in Guyancourt, France, a third one in Réunion, France, and a fourth one in Moratuwa, Sri Lanka.

The AERO and VISTA spacecraft will use commercial magnetometers to measure space weather events near Earth’s aurora. The small size of AERO and VISTA necessitate the use of magnetometers with small size, weight, and power. The magnetometers selected exhibit good precision, but additional calibration is needed to achieve good accuracy. This work reports on a method for calibration by regression which has reduced the magnetic observed error by a factor of ~50, meeting mission requirements.

Meltwater runoff estimates from the Greenland Ice Sheet contain uncertainty. To collect a dataset suitable for validating surface mass balance estimates of runoff, we installed a weather station and river stage sensors along three proglacial rivers in a cold-bedded area of NW Greenland without firn, crevasse, or moulin influence. The first three years (2019–2021) of observations have given us a first look at the seasonal and annual weather and hydrological patterns of this understudied region.

This paper presents a design for a 3D printed, rechargeable electrode that measures Self-Potential (SP) in different types of laboratory experiments. It is small, cheap, robust and stable, and offers the same performance as custom-machined laboratory standards. The use of 3D printing technology makes the electrode more versatile and cost-effective than traditional laboratory standards. Examples of its use under both low and high pressure have been included, as well as 3D printable designs.

We propose a new type of power station unit with wireless data transmission capability, which was not supported by same type of instrument in the market. Based on that, a novel distributed geophysical data acquisition architecture is also proposed. The proposed instrument loads more stations than industry leading LAUL-428, while providing additional wireless data transmission and NB-IoT remote control.

In this paper, local binary pattern (LBP), sparse representation and mixed logistic regression model are introduced, and a sample labeling method based on neighborhood information and priority classifier discrimination is presented. Then, a hyperspectral remote sensing image classification method based on texture features and semi-supervised learning is implemented.

Lidar networks coordinate efforts of different groups, providing guidelines to homogenize retrievals from different instruments. We describe an ongoing effort to develop a lidar processing pipeline (LPP) collaboratively. It is a collection of tools developed in C/C++, python, and Linux script that handle all the steps of a typical lidar analysis. We show case studies for Sao Paulo and Amazon, from which we envision a roadmap to guide future development, accommodating the needs of our community.

The study investigates how low cost technology can be applied in data scarce catchments to improve water resource management. More specifically, we investigate how drone technology can be combined with low-cost RTK GNSS equipment and subsequently applied in a 3 D hydraulic model so as to generate more physically based rating curves.

Soil moisture monitoring is important for many applications, from improving weather prediction to support agriculture practices. Our capability to measure this variable is still, however, limited. In this study we show the tests conducted on a new soil moisture sensor at several locations. The results show that the new sensor is a valid and compact alternative to more conventional non-invasive soil moisture sensors that can open the path to a wide range of applications.

This study aims to figure out the ideal cryptographic technique for End-To-End Encryption security for educational purposes. For this purpose, various encryption methodologies are compared to various metrics including encryption time, decryption time, retrieval time and number of data size versus Encryption for the NPTEL cloud database and an enhanced role-based technique has been suggested.

Motivated by recent community interest in a satellite mission to the atmospheric LTI region between 100 km and 200 km altitude, the DIPCont project is concerned with vertical profiles of key LTI variables and their reconstruction from dual-spacecraft and single-spacecraft observations. Considering a novel non-isothermal scenario, the report presents a set of self-consistent parametric models, introduces the probabilistic DIPCont modeling framework, and discusses first results.

Magnetic field measurements in space can be contaminated by stray magnetic fields from their host satellite. We present an automated tool for measuring the magnetic field generated by potential satellite and instrument components to identify those that may degrade the measurements taken on-orbit. This tool is designed for use by the Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) Small Explorers mission and is currently being used for mission design activities.

This paper outlines the development of a color filter wheel, attached to a broadband CL detector, which allows us to recover spectroscopic information and generate composite color images. The embedded data from the pixels were used to generate 2D and 3D graphs providing multiple visual pathways for comparing relative intensities. The design can be adjusted to accommodate various chamber specifications and expand the capabilities of the broadband CL detectors housed at many institutions.

DMA-based algorithm developed by the authors allows us to solve the main tasks of cyclostratigraphy: periodograms were constructed with further identification of repetitive cycles for carrying out geological reconstructions and correlations of sediments of the same age over a large area.

Based on an analysis of the differences between DEM and point cloud data, including the corresponding acquisition methods, data structures and model construction methods, this paper proposes a 3D point set data model based on regular grid 2D data field for regional modeling. The feasibility of the model is tested through the upper and lower boundary modeling method.

The daily variation amplitude of geomagnetic component Z could represent the diurnal variation strength of geomagnetic field. The ionospheric conductivity, neutral wind in ionosphere and the complicated underground electrical structures make combined action to effect the feature of the Z daily variation amplitude in China. This paper will provide the background information or reference to researchers who study the geomagnetic diurnal variation or to analyse the anomaly.

This study proves how the experimental results coincide with theoretical factors of LE-PIXE in case of High Grade Metamorphic Rocks and calibration of Si (Li) detector in case of low Z elements for future research. The Experimental parameters behind the low Z elements and also the developments of the same LE-PIXE by alter the various parameters and the complementary techniques which will be required for low energy X-rays emitted from low Z.

Analysis of non-uniqueness model in resistivity imaging data is vital in inaugurating the consistency of models. Nevertheless, such analysis is moderately unusual in resistivity imaging data set. Electrical resistivity tomography (ERT) technique is being constantly used in many scientific areas including engineering, environmental and archaeological survey.

This study investigates how useful the PIXE technique is in the analysis of complex matrix composition in earth materials. Hence it gives an information on PIXE in relation to other nuclear techniques. Results obtained by PIXE must be compared with other complementary techniques to obtain an overall elemental analysis of the matrix composition of high-grade earth materials. Finally, the results are reviewed.

This paper presents a quasi-distributed thrust measurement system based on an optical frequency domain reflectometer (OFDR). This OFDR sensing system achieved a spatial resolution of 20 cm using a 500 m test fiber (the resolution of an OTDR sensing system is generally approximately 1 m), the maximum measurement pressure can reach 1.059 MPa and the maximum relative error is 8.9 %. This system has good engineering application prospects in the safety monitoring field.

This article describes the development of a mobile roadside survey procedure for obtaining corroboration data for the remote sensing of agricultural land use practices over county level areas where atmospheric conditions are unfavourable for satellite remote sensing, while improving on financial, temporal, and safety costs for in-field verification data acquisition.

This paper gives an outlook of the research aimed at development of an instrument for magnetic field survey. The developed instrument performs accurate measurements of the parameters of the Earth’s magnetic field. Such measurements are required for control of magnetic environment at observational points where the Earth’s magnetic field is continuously measured. The developed instrument is considered as a possible standard solution for assessment of artificial noise at various locations.

Nowadays ocean-bottom observatories, equipped with acceleration and pressure gauges (seismometers and tsunameters), became widespread. We suggest simple and reliable method for remote testing the calibration of the gauges installed at the ocean bottom. The method is extremely convenient for practice, since, besides measured quantities, it involves a sole physical constant – the gravity acceleration.

The CUGB-CS48DAS data acquisition system was designed for seismic purpose at first. However, we tried to integrate the acquisition circuit and after several hardware improvements and software updates, it can be used now for seismic exploration as well as electrical prospecting. It has good application effects in engineering geology, mineral geology and energy geology, and is suitable for exploration tasks in coalfields, petroleum, minerals, earthquake monitoring and urban construction, etc.

Observations of the stable isotopes of water vapor by high-resolution ground-based Fourier transform infrared spectroscopy (FTIR) provide information on study of the variation of the atmospheric water vapor at Hefei site. In this paper, the percentage of atmospheric H₂O(X_H2O) and HDO (X_HDO) have been retrieved based on a high-resolution ground-based FTIR at Hefei site, and also calculated the stable isotopes of water composition δD. The time series of X_H2O were compared with the Greenhouse gase.

Terrestrial photogrammetry is the approach by which measurements are derived from images. It is a rapidly growing method in glaciology, providing detailed records of glacier change. However, glacial photogrammetry toolboxes are limited currently. PyTrx (freely available online) has been developed here as a Python-alternative toolbox with wider capabilities for deriving velocities, areas, and line measurements. Examples are presented throughout using time-lapse imagery from glaciers in Svalbard.

Meteorological observational data obtained in highly complex terrain has to be treated differently than it is usually done within state of the art quality control procedures. The main motivation and goal is to preserve as much information as possible in order to enhance the accuracy of analysis and forecast model output. It is recommended to use the method in highly complex terrain. Sufficient data density and coherent structures within data is required.

- This study aimed to calibrate some of the existing models in the literature for estimating daily total global solar radiation parameter using available measuring records (maximum and minimum air temperatures) and three new models are developed based on maximum and minimum air temperatures and relative humidity.
- In this study, three new models that are based on the relative humidity and the difference between maximum and minimum air temperatures were suggested.

A new investigation technique for magnetic data by a 2D dipping dike has been presented. The main interpretive parameters are: the depth to the top, exact origin, and the width of dipping dike. The comparison of the results with drilling information reported in the literature demonstrated the prevalence of the suggested method and its potential for solving magnetic problem, for example in china field example the depth to the top of dike is 22.24 m and from drilling information range from 22–25.

Radar Signal processing is one of the area where there is a lot of scope for research. This area demands efficient algorithms for study of echoes derived from various atmospheric regions. Denoising techniques were used and spectral moments were calculated. Stacked doppler profile was plotted to observe the improvement in doppler detection. It has been observed that there is a considerable improvement in recognition of the doppler echoes.

An automatic process for the estimation of forest properties in high spatial resolution using National Land Survey's airborne laser scanning data is presented. Results were evaluated by compering against national MS-NFI forest data. The estimation accuracy was generally good, but deciduous forests in leaf-off conditions caused somewhat underestimation. The method can be used to support e.g. forest managing, construction planning, wood industry and other remote sensing applications and research.