Accurate information on the terrain, tree heights and densities, forest stand condition is of great importance for the forest use, management of forest and natural resources. A source of such information is aerial photography, including multispectral, and airborne laser scanning.
NIR aerial images help determine the vegetation condition. The fact is that infrared radiation is well reflected by green parts of plants, and the more intense the red color in such an image, the healthier the vegetation. In addition, such images can be used to determine the composition of deciduous forests, as each species reflects light in a certain range of red.
LiDARs are unique in their ability to obtain data on the ground surface under vegetation. It allows one to build accurate digital elevation models for any kind of terrains and then to map them. The second important characteristic of modern LiDARs is the ability to capture and record an unlimited number of reflections from each outgoing pulse and receive coordinated data on the vegetation of different heights, wires and power transmission towers, building roofs, and ground surface. Thus, based on the laser scanning data, it is possible to measure the vertical structure of the forest canopy and predict the bulk density. All this can be used to determine the volume of biomass and applied to simulate the spread of forest fires.
- Mapping of forested areas,
- Definition of forest species composition,
- Classification by age, forest stand height, biological productivity,
- Monitoring of the forest condition (susceptibility to diseases and pests), degradation.
Thematic maps of forest lands
- Maps of species composition,
- Maps of the forest's susceptibility to disease and pests,
- Maps of biomass volume and wood stock.
Monitoring and control
- Control of the compliance with the forest protection regulations,
- Identification of illegal logging,
- Detection of forest fire fronts and tracking of fire spread,
- Monitoring of forest land dynamics under the adverse natural conditions (in boggy areas, drainless basins).
3D object modelKommunarka, 2018
3D object model for change detactionKommunarka, 2019
3D object model – measurements on the facade
3D object model with cadastral form
Modern city is a complex multi-level structure consisting of many interoperable systems supporting the city functions. The digital information and communication technologies are implemented to manage cities, to enhance the quality, performance, and interactivity of urban services, and to reduce costs and resource consumption. The digital twins being integral to the Smart City conception are developed.
Since 2014 Sigma Metrix has been creating 3D city models – the CityGML-based digital twins. Using our software, it is possible to automatically create the accurate geometric models of all free-standing buildings in the territory and to texturize the wall and roof surfaces fully automatically.
The major difference of our models is that each building is represented by a separate geometric model (object) with the exact coordinate references and orientation in a local coordinate system. Each model can have any quantity of text attributes (address, designated purpose, number of storeys, ownership, easements, floor space, volume, etc.). The attributes can be read from external data warehouses or be set on site. Models can be removed from the scene, migrated and merged, and the operations can be carried out both in the customer's local network and Internet environment.
All geometric models are stored in a standardized spatial data format – CityGML, which was developed and accepted by the Open Geospatial Consortium (OGC). Today it is an open platform to develop information and analytical systems for municipal administration.
It is significant that all the models "stand" on the real terrain, which makes it possible to build a single integration platform for various geospatial systems and services. This is a vivid model of the set of urban objects, which shows them in the dynamics as well, for example, in the development using the interfaces with BIM models.
The applications of 3D object models
- Visualization of the existing landscape and comparison with the current/future renovation or reconstruction projects - to coordinate activities of several contractors, optimize the design and construction processes, and control the compliance with the project documentation.
- Design of infrastructure, travel routes to redirect the human and traffic flows and to minimize any inconvenience to the citizens.
- Automatic geometric change detection of the features (area, number of storeys, etc.) occurred after the previous survey - for cadastral accounting and taxation.
- 3D cadastre.
- Assessment of the energy consumption to regulate the heating intensity, duration of heating season depending on the thermal efficiency in different buildings, the need and cost of renovation of heating systems. The model combines information about the building volume, number of floors, building type, and other characteristics to forecast the heating energy demand.
- Operational models of utilities - visualization of the requirements for repair, potentially accident-prone joints and junctions, and conductivity values.
- Ecological modeling and predictive analysis – movement simulation of air masses and emissions, noise pollution maps.
- Visualization of cultural heritage objects with the attributes of property rights, assessment of cultural heritage sites and their tourist attractiveness.
- Simulation and forecasting of the crowd movements in highly crowded areas (squares, stadiums, shopping centers) to develop the evacuation procedures in emergency.
- Analysis of the traffic flows based on information about the number of lanes, the availability of traffic lights, the speed limitation on certain road segments, areas of constant traffic congestion, to prevent traffic jams.
- Examination of the 3G/4G network coverage, realistic visualization of the sketchy coverage zones, and highlighting of the areas, where the communication quality should be improved.
- Improving the access (human mobility), routing for disabled people. In contrast to conventional 2D maps, it is possible to display landscape, curbs, stairs, slope steepness, and to append information about the existence of elevators, staircases, special crossing ways, traffic lights with sound signals, special markings on the roads, etc.