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1

SAR interferometry for landslide investigation and surface deformation monitoring: a case study of Souk Ahras area, north-east of Algeria

Gueraidia Nour El Houda, Fehdi Chemseddine, Gueraidia Saida

Geomatics, Landmanagement and Landscape

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2023

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no. 2

37--55

EN

Landslides – natural disasters be caused by various factors - are frequent in the region surrounding Souk Ahras. Comprehensive fieldwork, such as geotechnical drilling investigations and soil excavations, is conducted to monitor ground movements and assess the feasibility of geological locations. Synthetic Aperture Radar (SAR) and other active satellite remote sensors are utilized in Earth Observation-based systems to identify and track ground deformation and landslides in the study area. This research aims to illustrate how open-source processing software, SNAP, provided by the European Space Agency, can be combined with freely available datasets from Copernicus to accomplish this goal. In the North Eastern part of Algeria, which includes Souk Ahras, there is a high risk of landslides Through the use of InSAR technology, the research provided satisfactory results in identifying the morphology of landslides and generating a largescale interferometric map covering several regions in the East of Algeria, revealing the extent of distortion and spacing caused by the landslide phenomenon.

2

Comparative analysis of meteorological conditions on the shores of Szczecin Lagoon

Kasyk Lech, Pleskacz Krzysztof, Kapuściński Tomasz

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2022

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nr 70 (142)

83--93

EN

The definition of dynamic areas of searching for shipwrecks, and/or the movement of pollution across waters of Szczecin Lagoon first requires the knowledge and specification of hydro-meteorological conditions across the area. This article compares wind parameters from various sources of meteorological stations located close to Szczecin Lagoon. The wind speed and direction were obtained from Ueckermuende, I Brama Torowa (Urząd Morski Szczecin), and Kopice (wind meter of Szczecin Maritime Academy). Wind direction data analysis was based on directional statistics methods and tools.

3

Peptydomimetyki i foldamery aromatyczne w chemii biologicznej

Ledwoń Patrycja, Staśkiewicz Agnieszka, Jewgiński Michał, Latajka Rafał

Wiadomości Chemiczne

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2022

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[Z] 76, 5-6

349--363

EN

The interests of the research group working under the supervision of professor Rafał Latajka at the Department of Bioorganic Chemistry at the Wrocław University of Science and Technology are focused on several projects in the field of biological chemistry. Regardless of whether a given project concerns – the synthesis and activity of new enzyme inhibitors, peptides, peptidomimetics, or aromatic foldamers – the thread of correlation between the structure and activity of the studied systems always plays a pivotal role. In this article we are presenting current projects in our research group.

4

Szybki algorytm projekcji wstecznej oparty na współrzędnych barycentrycznych do zastosowań w aktywnych i pasywnych zobrazowaniach radarowych SAR

Radecki Krzysztof

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2022

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nr 4

575--578

PL

Algorytm projekcji wstecznej (ang. Back Projection Algorithm, BPA), stosowany w obrazujących z syntetyczną aperturą radarach, jest bardzo wymagającym rozwiązaniem pod względem złożoności obliczeniowej. Opisany w referacie algorytm projekcji wstecznej wykorzystujący współrzędne barycentryczne, dzięki innowacyjnej metodzie zawężania zakresu surowych danych radarowych potrzebnych do uzyskania zobrazowania, jest bardziej wydajny pod względem nakładu obliczeniowego w porównaniu do klasycznego algorytmu BPA i może być zastosowany w systemach radarowych pracujących w czasie rzeczywistym.

EN

Back projection (BP) algorithm is one of the most computationally demanding methods in Synthetic Aperture Radar (SAR) imaging technique. The huge computational complexity of this algorithm causes problems in real time radar systems. The article presents newly developed fast barycentic-based back projection algorithm which allows the classical well-known BP algorithm to be significantly accelerated. The described solution can be adapted to a real-time SAR systems.

5

Dual-band Textile AMC Antenna for WLAN/WBAN Applications on the Human Arm

Bouamra Wahida, Sfar Imen, Mersani Ameni, Osman Lotfi, Ribero Jean-Marc

International Journal of Electronics and Telecommunications

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2022

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Vol. 68, No. 2

209--216

EN

This article presents a low-profile and flexible dualband AMC Antenna operating at 2.45/ 5.8 GHz for wireless local area network (WLAN) on-body antenna applications using textile materials. A dual-band artificial magnetic conductor (AMC) structure with a dual hexagonal shape was used to reduce back radiation, therefore specific absorption rate (SAR), and improve the antenna performance parameters. To study the antenna/body interaction, a suitable comprehension and detailed studies of the wave propagation in the vicinity of the human arm in different meteorological conditions were carried out to demonstrate the effects of the skin condition on the antenna performance parameters. The simulation and measurement results indicate that electromagnetic communication on wet skin is viable. Acceptable SAR values were obtained, revealing that the body is well immune from the antenna electromagnetic radiation in functional wearable conditions. The proposed wearable AMC antenna provided engaging simulation and measurement results. It satisfies users' comfort and safety properties, making it a good candidate for WLAN/WBAN applications.

6

Characterization of Propagation Models at 5G Network and Effects of SAR on Human Brain

Al-Aamri Nawal, Nadir Zia, Bait-Suwailam Mohammed, Al-Lawati Hassan

International Journal of Electronics and Telecommunications

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2022

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Vol. 68, No. 2

343--349

EN

Nowadays, the world is turning into technology, fast internet and high signal quality. To ensure high signal quality, the network planners have to predict the pathloss and signal strength of the transmitted signal at specific distances in the design stage. The aim of this research is to provide a generalized pathloss model to suit the urban area in Muscat Governorate in the Sultanate of Oman. The research covers 5G network pathloss in the Muttrah Business District (MBD) area. It includes Close In (CI) model and Alpha Beta Gamma (ABG) model with 3.45GHz. The results of 5G models were compared with real experimental data in MBD by calculating Root Mean Square Error RMSE. Other cells at MBD area were used for reverification. To validate the modified pathloss models of 5G, they were applied at different cells in Alkhoud area. Furthermore, this paper also deals the effect of Specific Absorption Rate (SAR) on the human brain for ensuring safety due to close proximity to cell towers. The SAR values were calculated indirectly from the electric field strength of different antennas. Calculated results were compared with the international standards defined limits on the human brain.

7

Safety assessment of electromagnetic exposure for adult and child passengers standing on the subway platform

Li Jin, Lu Mai

Archives of Electrical Engineering

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2022

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Vol. 71, nr 3

755--773

EN

The objective of this work is to evaluate the safety of adult and child passengers exposed to a radio frequency (RF) source, i.e., a leaky coaxial cable (LCX) on the subway platform. An adult model, a child model, and an LCX model have been numerically designed in COMSOL Multiphysics software. The distributions of the induced electric field (E-field), specific absorption rate (SAR), magnetic field ( H-field) and the head temperature increase in adult and child passenger models were calculated at 900 MHz. The induced fields in the passengers were compared with that without screen doors. The results show that the E-field, SAR and H-field in the whole body of the child are 2.00 × 10 -2 V/m, 1.07 × 10 -7 W/kg, and 2.94 × 10 -4 A/m, respectively. The E-field, SAR and H-field in the central nervous system of the child are 1.00e × 10 -2 V/m, 2.44 × 10 -8 W/kg, and 2.41 × 10 -4 A/m, respectively. The maximum values of the E-field, SAR and H-field in the adult passenger are 1.49–2.34 times higher than those of the child. The E-field, SAR, and H-field in the passenger models without a screen door are larger than those with a screen door. The screen door has a partial shielding effect on the RF electromagnetic field. The values of the maximum temperature that increases in adult and child head tissue are 0.2114 and 0.2111℃ after waiting 6 minutes exposure, respectively. All calculated results are well below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) limits for general public exposure, indicating that RF electromagnetic exposure caused by the LCX on the subway platform is not a threat to passenger’s health.

8

Assessment and Mapping of Groundwater Quality for Irrigation and Drinking in a Semi-Arid Area in Algeria

Azlaoui Mohamed, Zeddouri Aziez, Haied Nadjib, Nezli Imed Eddine, Foufou Atif

Journal of Ecological Engineering

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2021

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Vol. 22, nr 8

19--32

EN

Groundwater is the main resource used to meet the people’s drinking water and irrigation needs of the Ain Oussera plain, because of the lack of surface-water resources. This paper intended to evaluate the suitability of groundwater for agriculture and drinking in the Ain Oussera plains. The data of the study were gathered and analyzed from twenty (20) groundwater samples collected to assess the plain groundwater quality, using the Water Quality Index (WQI) and GIS, carried out on physico-chemical parameters, including potential of hydrogen (pH), total dissolved solids (TDS) electrical conductivity (EC), potassium (K+), sodium (Na+), magnesium (Mg2+), and calcium (Ca2+) and major anions (Cl, HCO3, NO3, SO4), as well as, the water suitability test for agricultural purposes, using the sodium adsorption ratio. These parameters were inserted into the GIS platform to create a spatial distribution map for each parameter using the inverse interpolation technique (IDW). The results indicated that the concentrations are within the Algerian permissible limits. The water quality index (WQI), which evaluates the suitability of water for consumption, varies from 31 to 173 with an average value of 81. 70% of the samples from the Ain Oussera plain fall within the excellent and good quality categories. Its water is suitable for consumption (WQI < 100), while 30% is in the poor water category. From the calculation of SAR values, it was found that 90% of the groundwater samples are considered excellent and suitable for irrigation. According to the classification of the United States Salinity Laboratory USSL, the Ain Oussera water quality is classified as poor for irrigation purposes.

9

Ultrasonic specific absorption rate in nanoparticle-mediated moderate hyperthermia

Gambin Barbara, Kruglenko Eleonora

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 3

art. no. e137053

EN

Magnetic nanoparticle’s different applications in nanomedicine, due to their unique physical properties and biocompatibility, were intensively investigated. Recently, Fe₃O₄ nanoparticles, are confirmed to be the best sonosensitizers to enhance the performance of HIFU (high intensity focused ultrasound). They are also used as thermo-sensitizers in magnetic hyperthermia. A new idea of dual, magneto-ultrasound, coupled hyperthermia allows the ultrasound intensity to be reduced from the high to a moderate level. Our goal is to evaluate the enhancement of thermal effects of focused ultrasound of moderate intensity due to the presence of nanoparticles. We combine experimental results with numerical analysis. Experiments are performed on tissue-mimicking materials made of the 5% agar gel and gel samples containing Fe₃O₄ nanoparticles with φ = 100 nm with two fractions of 0.76 and 1.53% w/w. Thermocouples registered curves of temperature rising during heating by focused ultrasound transducer with acoustic powers of the range from 1 to 4 W. The theoretical model of ultrasound-thermal coupling is solved in COMSOL Multiphysics. We compared the changes between the specific absorption rates (SAR) coefficients determined from the experimental and numerical temperature rise curves depending on the nanoparticle fractions and applied acoustic powers.We confirmed that the significant role of nanoparticles in enhancing the thermal effect is qualitatively similarly estimated, based on experimental and numerical results. So that we demonstrated the usefulness of the FEM linear acoustic model in the planning of efficiency of nanoparticle-mediated moderate hyperthermia.

10

VTS simulator SAR module for rescue operation planning

Kotkowska Diana

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2020

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nr 62 (134)

151--160

EN

This article presents the capabilities of a SAR module during rescue operation planning and control. The Navi-Harbour SAR module was used during an exercise, which enabled an operator to plan and monitor the rescue operations of selected water areas. To present the basic capabilities of this module, we prepared a case for the SAR action for a man overboard in the Baltic Sea using actual available SAR resources in this area. For the basic assumptions of the scenario, a research plan was developed that included an assessment of the most probable position of a threatened unit, taking into account the weather conditions in this area.

11

Ship-iceberg detection & classification in sentinel-1 SAR images

Heiselberg H.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2020

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Vol. 14, no. 1

235--241

EN

The European Space Agency Sentinel-1 satellites provide good resolution all weather SAR images. We describe algorithms for detection and classification of ships, icebergs and other objects at sea. Sidelobes from strongly reflecting objects as large ships are suppressed for better determination of ship parameters. The resulting improved ship lengths and breadths are larger than the ground truth values known from Automatic Identification System (AIS) data due to the limited resolution in the processing of the SAR images as compared to previous analyses of Sentinel-2 optical images. The limited resolution in SAR imagery degrades spatial classification algorithms but it is found that the backscatter horizontal and vertical polarizations can be exploited to distinguish icebergs in the Arctic from large ships but not small boats or wakes.

12

Prediction of SAR of electromagnetic radiation due to virtual reality headsets in the human head

Poungsri Piyapat, Pechrkool Tanaporn, Pruksanubal Aphibal, Akkaraekthalin Prayoot

Przegląd Elektrotechniczny

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2020

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R. 96, nr 9

171--175

EN

Virtual reality (VR) headsets, 5G device, expose electromagnetic radiation to the human head led to concerns about the health effects. The purpose of this study is to predict the specific absorption rate (SAR) due to VR headsets in the human head. The study involves two biological models. Model A is a flat specific anthropomorphic mannequin (SAM). Model B is Model A inserted with a designed brain. The results are found that the SAR of model B is higher than that of model A, under the standard limits and not affected by temperature, short term memory, or memory load.

PL

Urządzenia wirtualnej rzeczywistości generują pola elektromagnetyczne. W artykule analizowano współczynnik SAR takich urządzeń dla dwóch modeli.

13

Monitoring of the Specific Absorption Rate in Terms of Electromagnetic Hazards

Michałowska Joanna, Wac-Włodarczyk Andrzej, Kozieł Joanna

Journal of Ecological Engineering

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2020

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Vol. 21, nr 1

224--230

EN

High-frequency electromagnetic field monitoring is extremely important for the environment. Recording and continuous observation of the levels of harmful factors and their evaluation should be examined by means of systematic and reliable measurements. The purpose of the present research stems from the need for verification and analysis whether modern phones are safe for users during telephone conversations. The analysis was carried out with the use of two ESM 120 and ESM 140 meters measuring the same devices simultaneously. The SAR (Specific Absorption Rate) describes the energy processes in the biological tissues exposed to electromagnetic fields (EMF). The maximum values recorded by the ESM 140 dosimeter are SAR = 0.5 mW/kg.

14

Zaawansowane techniki InSAR w monitorowaniu osuwisk

Perski Zbigniew

Przegląd Geologiczny

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2019

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Vol. 67, nr 5

351--359

EN

In recent years, there has been a rapid development of SAR acquisition techniques and all new satellite radar missions are equipped with SAR devices allowing beam steering. This paper presents results of experimental application of TerraSAR-X in ultra-high resolution SpotLight and Staring SpotLight modes for the area of the Just landslide in the Rożnow lake area. Another analyzed example was to use data of the medium resolution Sentinel-1 data acquired in the TOPS mode for the Huciska and Zapadle landslides in Szymbark. In this case, a network of 12 radar reflectors (corner reflectors) was installed to make the results independent of vegetation conditions on landslides. This study presents preliminary results of measurements and discusses the potential of applications and directions of further work.

15

Analysis of SAR coefficient in the base station antenna field

Ciosk Katarzyna

Przegląd Elektrotechniczny

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2019

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R. 95, nr 12

105--108

EN

The paper presents the analysis of the Specific Absorption Rate (SAR) coefficient for human body subjected to the electromagnetic field of the base station field. The biological model is prolate spheroid and the illumination is a uniform plane wave. The human body has been modeled using an isotropic lossy dielectric prolate spheroid. The calculations were done by semi-analytical method for different field parameters and body parameters. The aim of this study is to analyze the influence of different parameters on whole body SAR. The computations were made for gsm frequencies.

PL

W pracy przedstawiono analizę współczynnika SAR dla człowieka w polu dalekim stacji bazowych telefonii komórkowej. Przyjeto sferoidalny model ciała człowieka. Obliczenia przeprowadzono metodą opartą na analitycznym rozwiązaniu zagadnienia brzegowego dla różnych parametrów anten i parametrów ciała.

16

S-band and Ku-band SAR system development for UAV-based applications

Kaniewski Piotr, Komorniczak Wojciech, Leśnik Czesław, Cyrek Jacek, Susek Waldemar, Serafin Piotr, Łabowski Michał

Metrology and Measurement Systems

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2019

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Vol. 26, nr 1

53--64

EN

This paper describes a synthetic aperture radar system for tactical-level imagery intelligence installed on board an unmanned aerial vehicle. Selected results of its tests are provided. The system contains interchangeable S-band and Ku-band linear frequency-modulated, continuous wave radar sensors that were built within a frame of a research project named WATSAR, conducted by the Military University of Technology and WB Electronics S.A. One of several algorithms of radar image synthesis, implemented in the scope of the project, is described in this paper. The WATSAR system can create online and off-line radar images.

17

Aeronautical search and rescue - a modern challenge

Guba Marek

Journal of Mechanical and Transport Engineering

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2019

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Vol. 71, No 1

31--40

EN

The article presents elements of the aeronautical search and rescue (ASAR) system in Poland, its current state and operational challenges, which are caused mostly by its ASAR team-based structure. This makes addressing an aviation incident in Poland more challenging, especially when coupled with poor weather conditions or insufficient information available at the edges LZPR’s operational ranges. This analysis of ASAR comes as a response to recent aeronautical incidents, which showed inefficiencies of the system in Poland.

PL

W artykule przedstawiono elementy systemu ratownictwa lotniczego w Polsce, stan na dzień dzisiejszy oraz problemy związane z jego funkcjonowaniem, które wynikają z oparcia tego systemu na lotniczych zespołach poszukiwawczo-ratowniczych. W przypadku zdarzenia lotniczego na terytorium Rzeczypospolitej Polskiej może stanowić problem, gdy wystąpią nieodpowiednie warunki atmosferyczne lub działania w deficycie informacyjnym na granicy zasięgu LZPR. Próba zdiagnozowania stanu, w jakim znajduje się system ratownictwa lotniczego, jest konsekwencją zdarzeń lotniczych, które uwidoczniły niedomagania tego systemu i ukazały jego niedoskonałość.

18

The Evaluation of the Possibility to Use the Water from Quarry Lakes for Irrigation

Jawecki Bartosz, Kowalczyk Tomasz, Feng Ye

Journal of Ecological Engineering

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2019

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Vol. 20, nr 9

188--201

EN

The paper presents the evaluation of the possibility to use the water from five quarry lakes located in County Strzelin for the purposes of agricultural irrigation. The evaluation was based on the guidelines provided by FAO and in PN-84/C-04635. The average values of water quality indicators were as follows: electrical conductivity – 0.365 mS×cm-1; Sodium Adsorption Ratio – 0.75; Total Dissolved Solids – 233.9 mg×dm-3; water pH – 7.8; BOD5 – 1.6 mgO2×dm-3, while the average ion concentrations were: nitrates – 1.6 mgN-NO3×dm-3; sulphates – 188.5 mg SO4×dm-3; chlorides – 30.95 mg Cl×dm-3; sodium 22.6, mg Na×dm-3; manganese – 0.05 mg Mn×dm-3; and iron – 0.04 mg Fe×dm-3. The values of the analysed indicators were similar to the concentrations noted in natural lakes and unloaded water reservoirs. The water from the analysed quarry lakes met (with some minor limitations) the requirements that enable its use for agricultural irrigation, in particular sprinkler irrigation.

19

A Systematic Approach to Determining the Duty Cycle for Regenerative Comparator Used in WSN

Marathe Dipak S., Khot Uday P.

International Journal of Electronics and Telecommunications

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2019

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Vol. 65, No. 2

329--333

EN

A low power regenerative comparator is very useful in Successive Approximation Register (SAR) type Analog to Digital Converter (ADC) for a Wireless Sensor Node (WSN). A regenerative type comparator generates output pulses by comparing input with a reference input. This paper deals with control of a power with an adjustable duty cycle. The regenerative comparator with an adjustable duty cycle and a positive feedback of a latch will help in improving accuracy, speed and also in achieving the less power consumption. The optimum value of a duty cycle is determined with metastability timing constraints. The proposed low power regenerative comparator circuit is designed and simulated by using TSMC 180 nm CMOS technology. The comparator consumes power as low as 298.54 nW with a regenerative time 264 ps at 1 V power supply.

20

Selected decompression procedures for survivors who became saturated in a sunken wreck

Kłos R.

Zeszyty Naukowe Akademii Marynarki Wojennej

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2018

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R. 59 nr 2 (213)

17--34

EN

This article is one of the series dedicated to the DiveSMART Baltic project conducted to better coordination of international underwater rescue operations in the Baltic Sea. The project DiveSMART Baltic has received Flagship status. The article is the forth in the planned cycle of articles referring tasks realised in the Naval Academy in the framework of DiveSMART Baltic project. This article describes selected decompression procedures for victims who became saturated by air at maximum depth to H=30mH2O in the air pockets of the hull of a sunken wreck. This subject is associated with the work package four ‘Medical treatment’ of the DiveSMART Baltic project Identifies methods for different medical treatments in operational areas.

PL

Artykuł należy do serii dotyczącej projektu DiveSMART Baltic który jest związany z zapewnieniem lepszej koordynacji międzynarodowej akcji ratownictwa podwodnego w rejonie Morza Bałtyckiego. Projekt ten otrzymał status „projektu flagowego”. Artykuł jest czwartym z cyklu artykułów opisujących zadania realizowane przez Akademię Mary-narki Wojennej w ramach projektu DiveSMART Baltic. Scharakteryzowane są w nim wybrane procedury dekompresji poszkodowanych, którzy ulegli saturacji powietrznej na maksymalnej głębokości do H=30mH2O w powietrznych pułapkach wewnątrz zatopionego wraku. Tematyka dotyczy realizacji zadania czwartego pt. ‘Medical treatment’ of the DiveSMART project: Identifies methods for different medical treatments in operational areas.