THE STUDY OF THE “CETUS” UNMANNED AERIAL VEHICLE FOR TOPOGRAPHIC AERIAL SURVEYING

The work aims to analyze and study the possibilities of using “Cetus” unmanned aerial vehicle (UAV) for performing topographic aerial surveys. The authors developed and tested aircraft-type UAV for topographic aerial photography. The studies were conducted on a specialized landfill, at which there is an appropriate number of situational points whose coordinates are determined with high accuracy. These points were used as both reference and control points. The obtained UAV aerial survey materials were subjected to a phototriangulation process to determine the orientation elements and to analyze, first and foremost, the angular orientation elements. The surveying was carried out on a mountainous territory, where the spatial coordinates of 37 situational points were determined by the method of ground-based GPS survey with an average accuracy of up to 0.05 m. These points were used as reference and control points. Aerial photography was performed in such a way that the scale of the images was as uniform as possible. The design solutions implemented in the Cetus UAV provide all the possibilities to perform aerial surveys of territories in strict compliance with the projected flight parameters. UAV equipment provides the necessary real-time correction of the position of the aerial camera. At the same time the optimum straightness of routes, stability of scales and mutual overlapping of pictures is reached. Regarding the accuracy of obtaining the spatial coordinates of the points of terrain objects, using “Cetus” UAV surveys, plans can even be made on a scale of even 1: 1000. As a result of the creation of the UAV “Cetus”, it became possible to perform the topographic aerial survey of the territories and to create large-scale orthophotos that fully meet the instructions. As a result of testing the “Cetus” UAV, it can be used in production processes when drawing up topographic plans for a large-scale series: 1: 1000 – 1: 5000, which will significantly save the cost of performing topographic work.

The techniques and challenges of GPS surveying for vertical alignments in high-rise buildings

PurposeVertical alignment in high-rise building is a very important aspect. The architects are nowadays interested in improvising untypical complicated morphology in building designs which increase the difficulty in surveying for vertical alignments. Although the GNSS survey techniques are widely applied in constructions, there is a lack of data sources to explicitly expose their applicability in high-rise buildings and the challenges to be considered. This study has been oriented to find out the best suitable GPS survey technique for the vertical alignment in high-rise buildings and the practical challenges to be considered.Design/methodology/approachThe findings have been attained by analyzing the reliable data gained through experts' comments through structured questionnaire survey, case studies and experiments on different GPS survey techniques.FindingsThe findings express that the GPS techniques can be used for vertical alignments in high-rise buildings except for direct setting out for which only RTK GPS can be used. There are some practical challenges to be considered in such GPS applications.Research limitations/implicationsThe findings encourage the research community to further focus on the GNSS survey applications in the constructions of high-rise buildings.Practical implicationsThe research expresses applicability of easier and less time-consumed modern GNSS survey techniques instead of traditional survey methods for expediting building constructions.Social implicationsThe knowledge on such modern rapid survey techniques with accuracy, efficiency and reliability highly affects the process of infrastructure development.Originality/valueThe research presents a useful new knowledge on applying GNSS survey techniques for precise survey requirements in the construction industry and exposes the gateways for further researches and development.

A Study of Vegetation Geomorphology Relationship along the sections of Balasore and Kanthi Coastal Plains, India

Coastal geomorphology deals with the various landforms and different processes involved in the development of coast. In the alluvium coast, biology plays a significant role as a coastal process. The present study aims at the role of vegetation in the geomorphic system, with the main consideration of flora. The study has been conducted in an alluvium coast along the Bay of Bengal adjacent to the sections of Balasore and Kanthi coastal plain. The geomorphological map and Normalized Difference Vegetation Index (NDVI) have been generated with the help of Landsat 5 TM, Landsat 8 OLI & SOI Toposheet with the help of Arc GIS & Erdas Imagine software. The ground truthing of relationships between geomorphological units & vegetation types are established with the help of GPS survey and counting of species type. The selected nine environmental transects of Balasore and Kanthi coastal plains i.e. Dagara, Kankadapal, Talsari, Udaipur, Digha, Shankarpur, Tajpur, Mandarmani & Junput have been considered for assessing the role of vegetation in sediment accretion and sediment surface stability. The study shows that the surface stability is achieved with dense vegetation covers and their types in Mangrove Swamp, Salt marsh and sand dunes whereas; the erosional area of geomorphic units has less vegetation cover and insignificant species type. The perfect relationship are found in the shore transect of Balasore-Kanthi coastal interface area (New Digha to Bichitrapur). Finally, it is also observed that the above area is less disturbed by human activities in compare to others.

Facies architecture and time stratigraphic relationships of a confined trunk-tributary valley fill and unconfined fluvial system in the backwater of the Turonian Ferron-Notom Delta, Utah, U.S.A.

ABSTRACT This paper documents a tidally incised, mudstone-prone tributary valley fill linked to a trunk valley in the backwater limit of the Turonian Notom Delta of the Ferron Sandstone Member, Utah. High-resolution 3D photogrammetry models were used to correlate a 20-m-deep valley between 32 measured sections over a 1 km2 area. A GPS survey and GIS geostatistical tools were used to restore the morphology of the tributary valley. The restored valley floor is interpreted as a surface of tidal erosion, based on the overlying facies and surface morphology. Morphological similarities exist between this tributary valley and modern analogs observed in northern Australia, the Memramcook tributary in the Bay of Fundy, and Pleistocene sediments in the Gulf of Thailand. 40Ar/39Ar dating of sanidine crystals using multi-collector mass spectrometry allow for a re-evaluation of depositional rates and timing of 32 fluvial aggradation cycles (FACs) and 9 fluvial-aggradation cycle sets (FAC sets) in this sequence. The new dates show that the entire sequence was deposited in 15 ± 5 kyr, and show that Milankovitch cycles cannot account for the internal complexity of this fluvial stratigraphy, indicating likely autogenic control of the FAC sets. The lateral extent of FACs in floodplain deposits mapped in outcrop are correlated over tens to hundreds of meters, and scale to estimated channel widths reflecting the autogenic control. FAC sets can be correlated for up to 10 km along depositional strike, which suggest controls unrelated to the dynamics of individual channels and may show some elements of allogenic climate-driven processes.

SURVEY OF ARCHAEOLOGICAL SITES OF GORNY ALTAY USING UAV

The article describes a methodology for determining the boundaries of archaeological sites using GPS survey and unmanned aerial vehicles (UAVs) with subsequent registration in the cadastral record. The method of georeferencing and photogrammetric processing of orthophotomaps using a system of control points has been tested. The digital photogrammetric program Agisoft Metashape (company Agisoft LLC, St. Petersburg) was chosen for the research. By means the program an orthomosaic was obtained with georeferencing with the Local Coordinate System (LCS-04). The result of the work was the construction of topographic plans and the determination of the boundaries of archaeological sites in accordance with the "Methodology for determining the boundaries of the territories of archaeologi-cal heritage sites, recommended for use by the letter of the Ministry of Culture of the Russian Federa-tion No. 12-01- 39/05-AB dated 27.01.2012".

Present GPS velocity field along 1999 Izmit rupture zone: evidence for continuing afterslip 20 yr after the earthquake

SUMMARY In order to better assess earthquake hazards, it is vital to have a better understanding of the spatial and temporal characteristics of fault creep that occur on ruptured faults during the period following major earthquakes. Towards this end, we use new far-field GPS velocities from continuous stations (extending ∼50–70 km from the fault) and updated near-fault GPS survey observations, with high temporal and spatial density, to constrain active deformation along the Mw7.4, 1999 Izmit, Turkey Earthquake fault. We interpret and model deformation as resulting from post-seismic afterslip on the coseismic fault. In the broadest sense, our results demonstrate that logarithmically decaying post-seismic afterslip continues at a significant level 20 yr following 1999 Earthquake. Elastic models indicate substantially shallower apparent locking depths at present than prior to the 1999 Earthquake, consistent with continuing afterslip on the coseismic fault at depth. High-density, near-fault GPS observations indicate shallow creep on the upper 1–2 km of the coseismic fault, with variable rates, the highest and most clearly defined of which reach ∼12 mm yr−1 (10–15 mm yr−1, 95 per cent c.i.) near the epicentre between 2014–2016. This amounts to ∼half the long-term slip deficit rate.

Empirical Performance Analysis of Bus Speed and Delay at Intersections for Emerging Spot Improvement Programs

Many North American cities are increasingly interested in implementing small-scale localized spot treatments to surface routes as a simpler approach than top-down, disruptive route change, or redesign. This research seeks to support the identification of effective spot treatments at intersections using a systematic, data-driven approach. By analyzing key bus performance indicators in Toronto, this study developed insights into factors affecting peak-period bus speeds and delays at the segment and intersection levels for a wide variety of route and intersection configurations across eight high-frequency routes. Candidate treatments were then identified to improve bus performance. Data were sourced from the automatic vehicle location system, general transit feed specification, and a specialized ride check and GPS survey. Features of the approaches of 100 signalized intersections along the study routes were analyzed using K-means clustering, ordinary least squares regression, and regression trees, with target variables as their morning and evening peak operating speeds, segment-level delays, and signal delays. The results showed that long signal split is a significant contributor to higher operating speeds and lower delays, suggesting signal timing adjustments are an effective treatment. Clustering analysis suggested turning restrictions, particularly for right turns at intersections with near-side stops, could be effective, since turning volumes of similarly configured intersections were lower at locations with better transit performance. Regression analyses showed that queue jump lanes are an effective treatment if signal timing plans cannot be adjusted. The results from this study are intended to assist in informing transit authorities wishing to implement future spot improvement programs.