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Detecting abuses in archaeological areas using k-mean clustering analysis and UAVs/drones data

Qubaa Abdalrahman, Al-Hamdani Saja

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

2021

Vol. 30, No. 1

182--194

Unmanned aerial vehicles (UAVs) or drones have made great progress in aerial surveys to research and discover heritage sites and archaeological areas, particularly after having developed their technical capabilities to carry various sensors onboard, whether they are conventional cameras, multispectral cameras, and thermal sensors. The objective of this research is to use the drone technology and k-mean clustering algorithm for the first time in Nineveh Governorate in Iraq to reveal the extent of civil excesses and random construction, as well as the looting and theft that occur in the archaeological areas. DJI Phantom 4 Pro drone was used, in addition to using the specialized Pix4D program to process drone images and make mosaics for them. Multiple flights were performed using a drone to survey multiple locations throughout the area and compare them with satellite images during different years. Drone’s data classification was implemented using a k-means clustering algorithm. The results of the data classification for three different time periods indicated that the percentage of archaeological lands decreased from 90.31% in 2004 to 25.29% in 2018. Where the work revealed the extent of the archaeological area’s great violations. The study also emphasized the importance of directing authorities of local antiquities to ensure the use of drone’s technology to obtain statistical and methodological reports periodically to assess archaeological damage and to avoid overtaking, stolen and looted of these sites.

Heat waves in Poland in the period 1951-2015: trends, patterns and driving factors

Wibig J.

Meteorology Hydrology and Water Management. Research and Operational Applications

2018

Vol. 6, Iss. 1

37--45

Heat waves were analysed on the basis of maximum daily temperature from 24 meteorological stations in Poland. Heat waves are defined as the longest continuous period during which Tmax (daily maximum air temperature) is equal to or higher than 30°C in at least three days, the mean Tmax during the whole heat wave is equal or higher than 30°C and Tmax does not drop below 25°C during the whole period of heat wave duration. Heat waves occur in Poland from April to September with their maximums in July and August. Four-day-long heat waves are most frequent but the longest one lasted 31 days. The most persistent heat waves were in 1994 and 2015. An increasing trend in heat wave frequency and intensity is observed in Poland, however the increase is statistically significant at only about 60% of analysed stations. Four synoptic patterns favouring heat waves have been distinguished. A strong high over the Azores accompanies all of them, as well as slightly higher than normal pressure over Central Europe – this causes calm and sunny weather over Poland. Strong blocking appears over the North Atlantic during heat wave events, proofing that the development of strong heat waves in Poland is related to large scale circulation and that they are not of local origin. The analysis of the impact of soil moisture in months leading up to the development of heat waves should be the next step in analysis.