Drone-Mounted Lidar Survey of Maya Settlement and Landscape

2019 ◽  
Vol 30 (03) ◽  
pp. 630-636 ◽  
Author(s):  
Timothy M. Murtha ◽  
Eben N. Broadbent ◽  
Charles Golden ◽  
Andrew Scherer ◽  
Whittaker Schroder ◽  
...  
Keyword(s):  
Cost Effective ◽  
Ancient Maya ◽  
Maya Lowlands ◽  
Cultural Contexts ◽  
Future Studies ◽  
Piedras Negras ◽  
Digital Elevation ◽  
River Region ◽  
Surface Models ◽  
Aerial Vehicle

We conducted unmanned aerial vehicle lidar missions in the Maya Lowlands between June 2017 and June 2018 to develop appropriate methods, procedures, and standards for drone lidar surveys of ancient Maya settlements and landscapes. Three site locations were tested within upper Usumacinta River region using Phoenix Lidar Systems: Piedras Negras, Guatemala, was tested in 2017, and Budsilha and El Infiernito, both in Mexico, were tested in 2018. These sites represent a range of natural and cultural contexts, which make them ideal to evaluate the usefulness of the technology in the field. Results from standard digital elevation and surface models demonstrate the utility of deploying drone lidar in the Maya Lowlands and throughout Latin America. Drone survey can be used to target and efficiently document ancient landscapes and settlement. Such an approach is adaptive to fieldwork and is cost effective but still requires planning and thoughtful evaluation of samples. Future studies will test and evaluate the methods and techniques for filtering and processing these data.

scholarly journals Rockfall Risk Analysis Based on Precise Topography using UAV

2020 ◽  
Vol 20 (4) ◽  
pp. 63-73
Author(s):  
Jaehee Choi ◽  
Namgyun Kim ◽  
Bongjin Choe ◽  
Byonghee Jun
Keyword(s):  
Point Cloud Data ◽  
University Campus ◽  
Digital Map ◽  
Cloud Data ◽  
The Road ◽  
Mountainous Regions ◽  
Digital Elevation ◽  
Surface Models ◽  
Aerial Vehicle ◽  
Elevation Model

In this study, the risk of rockfall on incision slopes adjacent to roads was evaluated using the RocFall program. The study area was a slope adjacent to the road leading to a university campus in Samcheok-si, Gangwon-do, with an area of 774 m<sup>2</sup> and an average slope of approximately 43°. A rock shed was installed at the lower zone of the slope. A 3D model of the terrain was generated based on point cloud data gathered using a UAV (unmanned aerial vehicle). Fast and accurate orthoimages were captured by UAV and high-resolution digital surface models (DSMs) were produced; these data were used to assess the risk of rockfall. Compared to terrain extraction using a digital elevation model (DEM) generated from an existing digital map, terrain extraction using a UAV was more effective in deriving results close to the actual situation in the field, especially for the analysis of rockfall jump height and kinetic energy. The necessity of constructing 3D topographic data using UAVs to predict rockfall disasters in mountainous regions was confirmed.

scholarly journals Preserving the Activities of Daily Living Independence in Late Life

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 228-228
Author(s):  
Pao-feng Tsai ◽  
Thomas Jakobs ◽  
Reid Landes
Keyword(s):  
Training Program ◽  
Daily Living ◽  
Cost Effective ◽  
Computer Application ◽  
Maximum Effect ◽  
Activity Of Daily Living ◽  
Nursing Assistant ◽  
Future Studies ◽  
Certified Nursing Assistant

Abstract Levels of Assistance (LoA) is an effective caregiving intervention for maintaining activity of daily living (ADL) independence. It is a structured, almost prescriptive, approach to encourage completing ADLs as independently as an elder’s capabilities permit. With appropriate prompts and assistance during dressing, elders can overcome disability, express retained competencies, and experience success. Simultaneously, caregivers learn to view their functions as maintaining the quality of life of able elders, and they receive reinforcement from elders who are more confident and happier. This study is a continuation of a previous project that created and tested a computer application training program for LoA in nursing homes. We refined the app to include grooming LoA and tested on 10 certified nursing assistant (CNA)/resident dyads at a local nursing home. The pilot results showed, although we did not see consistent improvement in CNA’s dressing LoA, we achieved 10% to 30% improvement in grooming LoA. This indicates that the dressing assistance training is able to transfer to grooming LoA. With only an average of one-hour app training, this improvement is cost effective as compared to training provided by care professionals. Future studies should consider incorporating a culture change strategy to improve CNAs’ intention for assisting elders. In addition, the training program should be offered in the initial hire to achieve maximum effect.

The Chronology of Yaxuna

1998 ◽  
Vol 9 (1) ◽  
pp. 167-182 ◽  
Author(s):  
Charles Suhler ◽  
Traci Ardren ◽  
David Johnstone
Keyword(s):  
Cultural History ◽  
Cultural Development ◽  
The Political ◽  
Ancient Maya ◽  
Urban Center ◽  
Maya Lowlands ◽  
Terminal Classic ◽  
History Of ◽  
Late Formative ◽  
Middle Formative

AbstractResearch at the ancient Maya city of Yaxuna, located in the heart of the Yucatan Peninsula, has provided sufficient data to suggest a preliminary chronological framework for the cultural development of this large polity. Primary ceramic and stratigraphie data are presented to support a five-phase scheme of cultural history, encompassing the Middle Formative through Postclassic periods (500 b.c.–a.d. 1250). In addition to chronological significance, the political ramifications of a pan-lowland ceramic trade are addressed. Yaxuna experienced an early florescence in the Late Formative–Early Classic periods, when it was the largest urban center in the central peninsula. A second renaissance in the Terminal Classic period was the result of Yaxuna's role in an alliance between the Puuc and Coba, in opposition to growing Itza militancy. This paper proposes a chronological framework for the cultural development of one northern Maya region in order to facilitate an understanding of this area as part of the overall history of polity interaction and competition in the Maya lowlands.

scholarly journals Application of UAV-SfM photogrammetry and aerial lidar to a disastrous flood: repeated topographic measurement of a newly formed crevasse splay of the Kinu River, central Japan

2017 ◽  
Vol 17 (9) ◽  
pp. 1505-1519 ◽  
Author(s):  
Atsuto Izumida ◽  
Shoichiro Uchiyama ◽  
Toshihiko Sugai
Keyword(s):  
Lidar Data ◽  
High Definition ◽  
Central Japan ◽  
Aerial Photos ◽  
Data Resolution ◽  
Disastrous Flood ◽  
Surface Models ◽  
Elevation Changes ◽  
Aerial Vehicle ◽  
Crevasse Splay

Abstract. Geomorphic impacts of a disastrous crevasse splay that formed in September 2015 and its post-formation modifications were quantitatively documented by using repeated, high-definition digital surface models (DSMs) of an inhabited and cultivated floodplain of the Kinu River, central Japan. The DSMs were based on pre-flood (resolution: 2 m) and post-flood (resolution: 1 m) aerial light detection and ranging (lidar) data from January 2007 and September 2015, respectively, and on structure-from-motion (SfM) photogrammetry data (resolution: 3.84 cm) derived from aerial photos taken by an unmanned aerial vehicle (UAV) in December 2015. After elimination of systematic errors among the DSMs and down-sampling of the SfM-derived DSM, elevation changes on the order of 10−1 m – including not only topography but also growth of vegetation, vanishing of flood waters, and restoration and repair works – were detected. Comparison of the DSMs showed that the volume eroded by the flood was more than twice the deposited volume in the area within 300–500 m of the breached artificial levee, where the topography was significantly affected. The results suggest that DSMs based on a combination of UAV-SfM and lidar data can be used to quantify, rapidly and in rich detail, topographic changes on floodplains caused by floods.

Swamps, canals, and the locations of ancient Maya cities

Antiquity ◽  
1980 ◽  
Vol 54 (212) ◽  
pp. 206-214 ◽  
Author(s):  
R. E. W. Adams
Keyword(s):  
Radar Data ◽  
Classic Maya ◽  
Classic Period ◽  
Intensive Agriculture ◽  
Ancient Maya ◽  
Maya Lowlands ◽  
Rank Ordering ◽  
Topographic Information ◽  
Maya Civilization ◽  
Mapping Discovery

The recent radar mapping discovery of widely distributed patterns of intensive agriculture in the southern Maya lowlands provides new perspectives on classic Maya civilization. Swamps seem to have been drained, modified, and intensively cultivated in a large number of zones. The largest sites of Maya civilization are located on the edges of swamps. By combining radar data with topographic information, it is possible to suggest the reasons for the choice of urban locations. With the addition of patterns elicited from rank-ordering of Maya cities, it is also possible to suggest more accurate means of defining Classic period Maya polities.

Caves and Ancient Maya Ritual Use ofJute

2003 ◽  
Vol 14 (2) ◽  
pp. 207-219 ◽  
Author(s):  
Christina T. Halperin ◽  
Sergio Garza ◽  
Keith M. Prufer ◽  
James E. Bradya
Keyword(s):  
Religious Beliefs ◽  
Ancient Maya ◽  
Limited Data ◽  
Maya Lowlands ◽  
Freshwater Gastropods ◽  
Faunal Assemblages ◽  
Surface Sites ◽  
Ethnographic Data ◽  
Mother Earth ◽  
Ceremonial Architecture

AbstractA number of previous authors have suggested, based on limited data, thatPachychilusspp., freshwater gastropods often calledjute, may have played a role in ancient Maya ritual. Data collected by the authors demonstrate thatjuteshells consistently appear as part of faunal assemblages in ceremonial caves across the southern Maya Lowlands. At surface sites, jute are often associated with ceremonial architecture, particularly ballcourts. Previous ethnographic accounts are reviewed for clues to ancient Maya jute use. New ethnographic data suggest a role not previously considered by archaeologists. A Q‘eqchi’ Maya informant states that shells are gathered up after meals and deposited in caves as an offering in thanks to “Mother Earth” (Madre Tierra) who provided the mollusks. This practice suggests that the ancient shells may represent a secondary deposition rather than reflecting consumption occurring in the cave. The presence of jute shells may document ancient religious beliefs and ritual activities surrounding an important subsistence resource.

scholarly journals Terrain-Based Shadow Correction Method for Assessing Supraglacial Features on the Greenland Ice Sheet

2021 ◽  
Vol 2 ◽  
Author(s):  
Sasha. Z. Leidman ◽  
Åsa K. Rennermalm ◽  
Richard G. Lathrop ◽  
Matthew. G. Cooper
Keyword(s):  
Land Surface ◽  
Greenland Ice Sheet ◽  
Correction Method ◽  
Correction Coefficient ◽  
Digital Elevation ◽  
Aerial Vehicle ◽  
Sediment Cover ◽  
Elevation Model ◽  
Uav Images ◽  
Gis Software

The presence of shadows in remotely sensed images can reduce the accuracy of land surface classifications. Commonly used methods for removing shadows often use multi-spectral image analysis techniques that perform poorly for dark objects, complex geometric models, or shaded relief methods that do not account for shadows cast on adjacent terrain. Here we present a new method of removing topographic shadows using readily available GIS software. The method corrects for cast shadows, reduces the amount of over-correction, and can be performed on imagery of any spectral resolution. We demonstrate this method using imagery collected with an uncrewed aerial vehicle (UAV) over a supraglacial stream catchment in southwest Greenland. The structure-from-motion digital elevation model showed highly variable topography resulting in substantial shadowing and variable reflectance values for similar surface types. The distribution of bare ice, sediment, and water within the catchment was determined using a supervised classification scheme applied to the corrected and original UAV images. The correction resulted in an insignificant change in overall classification accuracy, however, visual inspection showed that the corrected classification more closely followed the expected distribution of classes indicating that shadow correction can aid in identification of glaciological features hidden within shadowed regions. Shadow correction also caused a substantial decrease in the areal coverage of dark sediment. Sediment cover was highly dependent on the degree of shadow correction (k coefficient), yet, for a correction coefficient optimized to maximize shadow brightness without over-exposing illuminated surfaces, terrain correction resulted in a 49% decrease in the area covered by sediment and a 29% increase in the area covered by water. Shadow correction therefore reduces the overestimation of the dark surface coverage due to shadowing and is a useful tool for investigating supraglacial processes and land cover change over a wide variety of complex terrain.

scholarly journals Lidar survey of ancient Maya settlement in the Puuc region of Yucatan, Mexico

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249314
Author(s):  
William M. Ringle ◽  
Tomás Gallareta Negrón ◽  
Rossana May Ciau ◽  
Kenneth E. Seligson ◽  
Juan C. Fernandez-Diaz ◽  
...  
Keyword(s):  
Landscape Archaeology ◽  
Formative Period ◽  
Ancient Maya ◽  
Late Classic ◽  
Maya Lowlands ◽  
Civic Architecture ◽  
Sensing Technology ◽  
Cultivable Land ◽  
Middle Formative ◽  
Storage Technologies

The application of lidar remote-sensing technology has revolutionized the practice of settlement and landscape archaeology, perhaps nowhere more so than in the Maya lowlands. This contribution presents a substantial lidar dataset from the Puuc region of Yucatan, Mexico, a cultural subregion of the ancient Maya and a distinct physiographic zone within the Yucatan peninsula. Despite the high density of known sites, no large site has been fully surveyed, and little is known about intersite demography. Lidar technology allows determination of settlement distribution for the first time, showing that population was elevated but nucleated, although without any evidence of defensive features. Population estimates suggest a region among the most densely settled within the Maya lowlands, though hinterland levels are modest. Lacking natural bodies of surface water, the ancient Puuc inhabitants relied upon various storage technologies, primarily chultuns (cisterns) and aguadas (natural or modified reservoirs for potable water). Both are visible in the lidar imagery, allowing calculation of aguada capacities by means of GIS software. The imagery also demonstrates an intensive and widespread stone working industry. Ovens visible in the imagery were probably used for the production of lime, used for construction purposes and perhaps also as a softening agent for maize. Quarries can also be discerned, including in some cases substantial portions of entire hills. With respect to agriculture, terrain classification permits identification of patches of prime cultivable land and calculation of their extents. Lidar imagery also provides the first unequivocal evidence for terracing in the Puuc, indeed in all northern Yucatan. Finally, several types of civic architecture and architectural complexes are visible, including four large acropolises probably dating to the Middle Formative period (700–450 B.C.). Later instances of civic architecture include numerous Early Puuc Civic Complexes, suggesting a common form of civic organization at the beginning of the Late Classic demographic surge, (A.D. 600–750).

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