Aspects of Aerial Laser Scanning when exploring unknown archaeological sites (Case study)

The current dramatic episodes of destruction of archaeological sites have again highlighted the problem of the safeguarding the threatened heritage and, if possible, recovering those damaged by all the armed conflicts of the past. The historical photogrammetry offers the possibility to recover a posteriori the geometrical and material properties of destroyed structures, reconstructing their 3D model to document, study and maintain their memory, until to support their real anastylosis. The presented work is about the 3D reconstruction of the civic tower of the little town of Sant’Alberto, near the city of Ravenna, Italy. The tower, as a symbol of resistance and pride of the town's population, was destroyed in December 1944 by German troops in retaliation, when they were forced to leave the area. A city committee has subsequently collected all the historical evidence concerning the tower, including a series of photographic images that can be used for the photogrammetric reconstruction; the images calibration and orientation have been solved using the geometric information derived by a terrestrial laser scanner survey realized in the area where the tower was originally located. Despite the scarcity and very poor quality of the available images, the conducted photogrammetric procedure has allowed a complete and qualitatively satisfying object reconstruction, also thanks to the use of geometric constraint tools offered by the chosen software. The integration between the obtained model of the old tower and the 3D TLS survey of the square made it possible to reconstruct the ancient situation of the area.

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THE FUSION OF EXTERNAL AND INTERNAL 3D PHOTOGRAMMETRIC MODELS AS A TOOL TO INVESTIGATE THE ANCIENT HUMAN/CAVE INTERACTION: THE LA SASSA CASE STUDY

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliii-b2-2020-1443-2020 ◽

2020 ◽

Vol XLIII-B2-2020 ◽

pp. 1443-1450

Author(s):

L. Alessandri ◽

V. Baiocchi ◽

S. Del Pizzo ◽

F. Di Ciaccio ◽

M. Onori ◽

...

Keyword(s):

Laser Scanning ◽

3D Models ◽

Second World War ◽

World War ◽

Double Frequency ◽

Aerial Laser Scanning ◽

Complex Morphology ◽

Internal Part ◽

Second World

Abstract. Caves have been used by humans and animals for several thousand years until present but, at these time scales, their structures can rapidly change due to erosion and concretion processes. For this reason, the availability of precise 3D models improves the data quality and quantity allowing the reconstruction of their ancient appearance, structure and origin. However, caves are usually characterised by lack of light, high percentage of relative humidity, narrow spaces and complex morphology. Thus, quite often the traditional topographic instruments cannot be employed. In the La Sassa cave (Sonnino, Italy) a huge deposit ranging from Pleistocene to the Second World War has been found and stratigraphic evidence suggested that the shape of the cave and its entrance might have been different. In this paper, the fusion of the internal and external 3D photogrammetric models of the La Sassa, made to support the archaeological excavations, is presented, A Nikon camera with a fisheye lens and a smartphone camera have been used to survey the internal part of the cave, while an aerial drone has been employed for the external area. The two models have been georeferenced and scaled using GCPs acquired by a double frequency GNSS (GPS and GLONASS) receiver. A low-resolution DTM derived from a previous aerial laser scanning survey and the 3D models have been elaborated in CloudCompare environment to highlight the complete morphology of the cave and its surroundings.

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Aerial Laser Scanning in Archeology

Geoinformatics FCE CTU ◽

10.14311/gi.6.14 ◽

2011 ◽

Vol 6 ◽

pp. 103-108

Author(s):

Martina Faltýnová ◽

Karel Pavelka

Keyword(s):

Public Service ◽

Laser Scanning ◽

Archaeological Sites ◽

Surface Model ◽

Archaeological Research ◽

Digital Surface Model ◽

Limited Size ◽

Aerial Laser Scanning ◽

Custom Made ◽

Data Source

Technology of aerial laser scanning is often well used for a DTM generation. The DTM (digital surface model) displayed in appropriate form, e.g. shaded surface, can be used as a data source for searching for archaeological sites. Aerial laser scanning data acquisition is unfortunately too expensive for non-commercial projects. It can be solution to use the ALS data acquired primarily for another reason by public service. This data has in general lower density, than expensive custom-made data, but can be borrowed for research purpose in a limited size. We tested the data from The Czech Office for Surveying, Mapping and Cadastre. The aim was to find, if it is possible to use data characterized by density of about 1 point/m2 for archaeological research. We used the DTM in form of shaded surface and inspect the data around few well known archaeological sites from different periods. It is also possible to use different outputs from the original DTM to better display terrain discontinuities, which could be caused by human activity.

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Low Temperature Fault Isolation Using Soft Defect Localization

ISTFA 2012: Conference Proceedings from the 38th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2012p0596 ◽

2012 ◽

Author(s):

Kristopher D. Staller

Keyword(s):

Low Temperatures ◽

Laser Scanning ◽

Low Cost ◽

Fault Isolation ◽

Laser Scanning Microscopy ◽

Cold Temperature ◽

Multiple Point ◽

Defect Localization ◽

Low Levels

Abstract Cold temperature failures are often difficult to resolve, especially those at extreme low levels (< -40°C). Momentary application of chill spray can confirm the failure mode, but is impractical during photoemission microscopy (PEM), laser scanning microscopy (LSM), and multiple point microprobing. This paper will examine relatively low-cost cold temperature systems that can hold samples at steady state extreme low temperatures and describe a case study where a cold temperature stage was combined with LSM soft defect localization (SDL) to rapidly identify the cause of a complex cold temperature failure mechanism.

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A LOOK INTO THE EARTH: EVALUATING THE USE OF MAGNETIC SURVEY IN AFRICAN ARCHAEOLOGY

Journal of African Archaeology ◽

10.3213/1612-1651-10018 ◽

2004 ◽

Vol 2 (1) ◽

pp. 49-63 ◽

Cited By ~ 6

Author(s):

Carlos Magnavita ◽

Norbert Schleifer

Keyword(s):

Geophysical Methods ◽

Field Research ◽

Archaeological Sites ◽

Magnetic Survey ◽

The Past ◽

Common Technique ◽

Sub Saharan ◽

Prehistoric Settlements ◽

Present Case Study

In the last decades, geophysical methods such as magnetic survey have become a common technique for prospecting archaeological sites. At sub-Saharan archaeological sites, however, magnetic survey and correlated techniques never came into broad use and there are no signs for an immediate change of this situation. This paper examines the magnetic survey undertaken on the Nigerian site of Zilum, a settlement of the Gajiganna Culture (ca 1800-400 BC) located in the Chad Basin and dated to ca 600-400 BC. By means of the present case study, we demonstrate the significance of this particular type of investigation in yielding complementary data for understanding the character of prehistoric settlements. In conclusion, we point out that geophysical methods should play a more important role in modern archaeological field research, as they furnish a class of documentation not achievable by traditional survey and excavation methods, thus creating new perspectives for interpreting the past of African societies.

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Detection of Asphalt Pavement Cracks using mobile 2D laser scanning system: A case study of UTM 30LX laser scanner

Journal of Physics Conference Series ◽

10.1088/1742-6596/1793/1/012038 ◽

2021 ◽

Vol 1793 (1) ◽

pp. 012038

Author(s):

Viet Quoc Tran ◽

Phuong Anh Thi To ◽

Thi Ngoc Huynh ◽

Anh Thu Thi Phan

Keyword(s):

Laser Scanning ◽

Asphalt Pavement ◽

Laser Scanner ◽

Scanning System ◽

System A ◽

Laser Scanning System

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Multitemporal–Multispectral UAS Surveys for Archaeological Research: The Case Study of San Vincenzo Al Volturno (Molise, Italy)

Remote Sensing ◽

10.3390/rs13142719 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2719

Author(s):

Nicodemo Abate ◽

Alessia Frisetti ◽

Federico Marazzi ◽

Nicola Masini ◽

Rosa Lasaponara

Keyword(s):

Middle Ages ◽

Principal Component ◽

Archaeological Site ◽

Archaeological Sites ◽

Medieval Art ◽

Archaeological Data ◽

History Of ◽

Close Range ◽

Low Altitude

Unmanned aerial vehicles are currently the most used solution for cultural heritage in the field of close range and low altitude acquisitions. This work shows data acquired by multitemporal and multispectral aerial surveys in the archaeological site of San Vincenzo al Volturno (Molise, Italy). The site is one of the most important medieval archaeological sites in the world. It is a monastic settlement that was particularly rich during the early Middle Ages, and is famous for its two full-frescoed crypts which represent a milestone in the history of medieval art. Thanks to the use of multispectral aerial photography at different times of the year, an area not accessible to archaeological excavation has been investigated. To avoid redundancy of information and reduce the number of data to be analysed, a method based on spectral and radiometric enhancement techniques combined with a selective principal component analysis was used for the identification of useful information. The combination of already published archaeological data and new remote sensing discoveries, has allowed to better define the situation of the abbey during the building phases of the 8th/9th century and 11th century, confirming and adding new data to the assumptions made by archaeologists.

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HEIGHT DETERMINATION TECHNIQUES FOR THE NEXT NATIONAL HEIGHT SYSTEM OF FINLAND - A CASE STUDY

Geodesy and Cartography ◽

10.3846/20296991.2015.1120387 ◽

2015 ◽

Vol 41 (4) ◽

pp. 145-155

Author(s):

Timo Saari ◽

Markku Poutanen ◽

Veikko Saaranen ◽

Harri Kaartinen ◽

Antero Kukko ◽

...

Keyword(s):

Laser Scanning ◽

Pilot Project ◽

Satellite System ◽

Reference Station ◽

Virtual Reference ◽

Precise Levelling ◽

Height Determination ◽

Weak Points ◽

Global Navigation Satellite

Precise levelling is known for its accuracy and reliability in height determination, but the process itself is slow, laborious and expensive. We have started a project to study methods for height determination that could decrease the creation time of national height systems without losing the accuracy and reliability that is needed for them. In the pilot project described here, we study some of the alternative techniques with a pilot field test where we compared them with the precise levelling. The purpose of the test is not to evaluate the mutual superiority or suitability of the techniques, but to establish the background for a larger test and to find strong and weak points of each technique. The techniques chosen for this study were precise levelling, Mobile Laser Scanning (MLS) and Global Navigation Satellite System (GNSS) levelling, which included static Global Positioning System (GPS) and Virtual Reference Station (VRS) measurements. This research highlighted the differences of the studied techniques and gave insights about the framework and procedure for the later experiments. The research will continue in a larger scale, where the suitability of the techniques regarding the height systems is to be determined.

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