Topographic Maps Research Articles

Changes in the extent of a glacier based on topographic maps and satellite images - possibilities and limitations on the example of the de Ferpecle glacier

Changes in the extent of a glacier based on topographic maps and satellite images - possibilities and limitations on the example of the de Ferpecle glacier

An Algorithm for Generating Outdoor Floor Plans and 3D Models of Rural Houses Based on Backpack LiDAR.

As the Rural Revitalization Strategy continues to progress, there is an increasing demand for the digitization of rural houses, roads, and roadside trees. Given the characteristics of rural areas, such as narrow roads, high building density, and low-rise buildings, the precise and automated generation of outdoor floor plans and 3D models for rural areas is the core research issue of this paper. The specific research content is as follows: Using the point cloud data of the outer walls of rural houses collected by backpack LiDAR as the data source, this paper proposes an algorithm for drawing outdoor floor plans based on the topological relationship of sliced and rasterized wall point clouds. This algorithm aims to meet the needs of periodically updating large-scale rural house floor plans. By comparing the coordinates of house corner points measured with RTK, it is verified that the floor plans drawn by this algorithm can meet the accuracy requirements of 1:1000 topographic maps. Additionally, based on the generated outdoor floor plans, this paper proposes an algorithm for quickly generating outdoor 3D models of rural houses using the height information of wall point clouds. This algorithm can quickly generate outdoor 3D models of rural houses by longitudinally stretching the floor plans, meeting the requirements for 3D models in spatial analyses such as lighting and inundation. By measuring the distance from the wall point clouds to the 3D models and conducting statistical analysis, results show that the distances are concentrated between -0.1 m and 0.1 m. The 3D model generated by the method proposed in this paper can be used as one of the basic data for real 3D construction.

Comparison of spatial orientation using topographic map and orthophotomap in a virtual environment representing urban space

Comparison of spatial orientation using topographic map and orthophotomap in a virtual environment representing urban space

Using open and collaborative data to improve the Brazilian topographic mapping in protected areas

Using open and collaborative data to improve the Brazilian topographic mapping in protected areas

Topographic mapping from space dedicated to Dr. Karsten Jacobsen’s 80th birthday

Topographic mapping from space dedicated to Dr. Karsten Jacobsen’s 80th birthday

Statistical Characterization of Emitter Fabrication over Electrospray Array Thruster

A method for characterizing the variance in fabrication of emitters and extractors in a porous conical electrospray array thruster is presented. Coherence scanning interferometry is used to produce topographic maps of 543 of 576 sites within the array. The emitter and extractor geometries, features of size a few hundred micrometers, are modeled as a spherically capped cone recessed from a circular aperture. Regressing this model against the topographic maps yields a set of salient parameters that describe the geometry of a site, including the tip radius and height of the emitter and its offset from the extractor aperture. Statistics over the emitter geometries are computed, which represent manufacturing tolerances. It is found that key parameters like the emitter tip radius are highly variable (mean 25.8 μm and standard deviation 20.9 μm), highlighting the stochastic nature of the manufacturing process. Correlations between the tip radius and emitter height indicate that this variability arises from blunting of the emitters during fabrication, and the observation that emitters are shorter than nominal is explained by an increase in effective cutting diameter of the tools. Further analysis indicates that determining the mean emitter tip radius of the entire population within 5% error requires over 300 individual emitter measurements. These results indicate that accurately quantifying emitter variability at scale requires rigorous and extensive analysis, and the implications of this emitter variability for device performance and design are discussed.

Bathymetric Map Production of Therthar Depression Basin and Water Storage Volume Estimation

Water crisis, drought, and desertification are prominent environmental issues facing many countries and threaten their sustainable development. Therthar depression basin in Iraq was selected as a study area. A new approach was adapted in producing a bathymetric map by merging contours derived from both topographic maps and digital elevation models using ArcGIS applications. Water storage volumes were estimated from 2017 to the end of 2023 using the trapezoidal rule. The results demonstrate that the maximum water storage volume was 80% of the total storage capacity in 2019. In 2021, this percent began to decrease significantly as a result of climatic changes until reached a dead storage about 40% in 2023. Large surface area of Therthar depression leads to increased evaporation and infiltration rates. The water consumption exceeded the incoming water storage by 5.292 billion cubic meters (bcm) in May and 13.127 bcm in October, between 2017 and 2023. The comparison between the estimated and actual live storage volumes resulted a root mean square error of 0.534 m and a coefficient of determination (R2) equals 0.871. However, to award off flood risks in rainy years, the study proposes increasing Therthar depression design elevation to 67 m rather than 65 m in proportion to Therthar arranger gate level.

Tracing the fate of hay meadows with haylofts in Slovakia: A geographical perspective

Abstract The paper focuses on the historical distribution of haylofts in Slovakia, geographical conditions related to hay meadows with haylofts, and land cover changes of former hayloft localities. Moreover, the current state of preserved haylofts and the land use of their surrounding area were documented at a regional scale, during the field research. A map of the historical occurrence of haylofts was digitised based on the Czechoslovakian military topographic maps from 1952–1957 (1:25,000). Altogether, 9,742 haylofts were recorded. The haylofts were usually built in mountain and sub-mountain areas on places with low soil quality, mostly at higher elevations, on moderate or moderately steep slopes and in more distant and isolated areas. About half of former hayloft meadows now exist as meadows or pastures with different intensity of grassland management. Forest or shrubs already cover the other 38% of the sites. To a lesser extent, the areas have been converted into arable land or recreational areas. Only a few haylofts have survived to this day; for example, in Upper Liptov Region, it is only 1% of their former abundance in this area (48 haylofts). Apart from a few positive cases where they have been restored or preserved, those that have survived continue to decay.

Topographic Map of Jinpyo’s Thought and its Two Lines of Succession : Focusing on the Contents of Zhancha Jing

Topographic Map of Jinpyo’s Thought and its Two Lines of Succession : Focusing on the Contents of Zhancha Jing

Local organization of spatial and shape information in the primate prefrontal cortex.

The current understanding of sensory and motor cortical areas has been defined by the existence of topographical maps across the brain surface, however, higher cortical areas, such as the prefrontal cortex, seem to lack an equivalent organization, and only limited evidence of functional clustering of neurons with similar stimulus properties is evident in them. We thus sought to examine whether neurons that represent similar spatial and object information are clustered in the monkey prefrontal cortex and whether such an organization only emerges as a result of training. To this end, we analyzed neurophysiological recordings from male macaque monkeys before and after training in spatial and shape working memory tasks. Neurons with similar spatial or shape selectivity were more likely than chance to be encountered at short distances from each other. Some aspects of organization were present even in naïve animals, however other changes appeared after cognitive training. Our results reveal that prefrontal microstructure automatically supports orderly representations of spatial and object information.

Landscape changes in Czech large protected areas 1950–2020: Two different landscapes types on the same path

Landscape and its development is crucial for viability and management of protected areas, therefore, we focused on Czech large protected areas and analysed their land cover and landscape structure changes from the 1950s to recent times. Based on four milestones (1950, 1990, 2004 and 2020), data from topographic maps and aerial imagery were vectorized and use for following steps as analysing main trends of changes: an increase in forest in all areas and extensification of agriculture; the latter was expressed by permanent grassland growth in almost all areas and by arable land decrease. Urbanisation was reflected in the growth of built-up areas. However, these changes did not take place equally across all protected areas. Therefore, we distinguished two groups: 1) more stable (in terms of land cover change) and forested areas; 2) protected landscape areas which were also established for conservation of cultural landscape with open land cover categories, which showed larger changes. Moreover, landscape structure shows its simplification during the study period across almost all protected areas. Therefore, our results indicate that, in some protected areas, landscape stability and in some others landscape diversity are their values.

Partial reconstruction of sparse and incomplete point clouds applied to the generation of corneal topographic maps of healthy and diseased patients

The presence of unmeasured areas or areas with missing data in corneal topographies greatly affect the quality of digital corneal models. These are more frequent in posterior than in anterior corneal surface. This work seeks to complete and improve digital corneal models generated from incomplete point clouds obtained with commercial tomographic equipment, applying three interpolation/extrapolation techniques based on population data (Polynomial, Biharmonic Splines and Cubic Radial Base Functions). 43 personalized corneal models of patients with different grades of keratoconus were used to test each interpolation method. All interpolation results were compared using the Mean Average Percentage Error (MAPE) index, observing that it is possible to interpolate/extrapolate up to the radius 5.2 mm on the anterior face and up to 4.2 mm on the posterior face in general, but none of the methods stand out above the others for all the situations considered. Consequently, extrapolation method must be chosen carefully.

3D Map Application on Cave Geosites in Relationship of Cave Morphometry and Surface Geomorphology in Karst Areas at Ngalau Basurek Cave, Silokek Geopark

On 2 January 2018, the local government proposed Silokek, a region in the Sijunjung Regency, West Sumatra Province, Indonesia, as a geopark, based on district rule number 188.45/3/KPTS-BPT-2018. This arrangement was based on the idea that a geopark would provide tourist destinations with natural tourism and archaeological, environmental, historical, educational, and cultural components in addition to geology, making this place an indirect example of a complex tourist destination. The Ngalau Basurek Cave is a geosite in this area that is a well-liked tourist destination, although it does not yet have a useful and instructive cave morphometry map. Producing cave morphometric data using the compass and step mapping method and geomorphological analyses of Landsat 8 image data is suggested to identify patterns of relationships with surface karst morphological features. A northeast dip angle trend was visible in the fresh limestone of the Kuantan Formation, which formed cave features as a result of dissolution. The dolinas, uvalas, and cone–kart features, which are represented on topographic maps (DEM-SRTM), demonstrate comparable trends. Dip-angle and strike-line trends were used to obtain a complete relationship between cave morphometry and surface geomorphology in Silokek Geopark.

Improved motor imagery training for subject's self-modulation in EEG-based brain-computer interface.

For the electroencephalogram- (EEG-) based motor imagery (MI) brain-computer interface (BCI) system, more attention has been paid to the advanced machine learning algorithms rather than the effective MI training protocols over past two decades. However, it is crucial to assist the subjects in modulating their active brains to fulfill the endogenous MI tasks during the calibration process, which will facilitate signal processing using various machine learning algorithms. Therefore, we propose a trial-feedback paradigm to improve MI training and introduce a non-feedback paradigm for comparison. Each paradigm corresponds to one session. Two paradigms are applied to the calibration runs of corresponding sessions. And their effectiveness is verified in the subsequent testing runs of respective sessions. Different from the non-feedback paradigm, the trial-feedback paradigm presents a topographic map and its qualitative evaluation in real time after each MI training trial, so the subjects can timely realize whether the current trial successfully induces the event-related desynchronization/event-related synchronization (ERD/ERS) phenomenon, and then they can adjust their brain rhythm in the next MI trial. Moreover, after each calibration run of the trial-feedback session, a feature distribution is visualized and quantified to show the subjects' abilities to distinguish different MI tasks and promote their self-modulation in the next calibration run. Additionally, if the subjects feel distracted during the training processes of the non-feedback and trial-feedback sessions, they can execute the blinking movement which will be captured by the electrooculogram (EOG) signals, and the corresponding MI training trial will be abandoned. Ten healthy participants sequentially performed the non-feedback and trial-feedback sessions on the different days. The experiment results showed that the trial-feedback session had better spatial filter visualization, more beneficiaries, higher average off-line and on-line classification accuracies than the non-feedback session, suggesting the trial-feedback paradigm's usefulness in subject's self-modulation and good ability to perform MI tasks.

Специализированные топографические карты: становление, тенденции развития научного направления, технология создания

The prerequisites for dividing topographic maps and plans into basic and specialized ones are highlighted. The trends of specialized maps improvement as a scientific direction of topographic mapping influenced by accumulated experience of production work and scientific research were established. Increasing relevance and demand for making specialized maps of environment-forming objects with great natural and ecological potential is shown. The concept of 'type of specialized maps' is substantiated; it determined the structure and sequence of map-making technological stages. A technology for mapping environmental protection is proposed using the example of wetlands with unique biospheric functions. Its specific features at different stages of the process are revealed

Cascading consequences of structural interventions in a tropical wandering gravel‐bed river

AbstractRiverscapes are often modified and managed through ‘command and control’ structural engineering approaches. These structures not only alter flow and sediment transport patterns but also negatively affect riverscape biodiversity. These impacts are particularly acute for rivers that are characterised by high mobility and wide flow distribution during extreme events. We used hydrodynamic and geomorphological change assessment to appraise the impacts of existing flood structures and their potential for removal in a tropical wandering gravel‐bed river in the Philippines. Our approach informs a systematic decision‐making process to screen opportunities for channel reconnection. Two‐dimensional hydraulic modelling showed flood structures confine flood water within the active channel for more frequent flood events, but banks are overtopped during larger magnitude events (>50‐year recurrence interval). Incorporating modelling results, a multi‐criteria analysis was developed to appraise opportunities for river reconnection based on structure purpose, functionality, and local land‐use. We differentiate among four actions for each structure: removal, redesign, set back, or retention. One structure is recommended for removal because it cuts off an anabranch, reduces channel capacity, and increases main anabranch bed shear stress. Increased potential for bed and bank erosion due to the structure's presence had a cascading effect, resulting in further interventions downstream and on the opposite bank. We show how the use of system‐scale two‐dimensional hydraulic modelling alongside high‐resolution topographic mapping can support management of interventions to reconnect a river to its wider anabranch‐bar morphology. Such actions form part of proactive, adaptive, and nature‐based flood management plans with local and non‐local benefits.

Calibration and validation of a multi-beam LiDAR onboard China Chang’e lunar probe for landing obstacle avoidance

For automatic exploration of specific areas with high scientific value on the moon and other planets, high-precision obstacle detection and hazard avoidance capabilities are required. Three-dimensional (3D) LiDAR can obtain a high-resolution 3D point cloud, offering significant advantages in landing obstacle avoidance. During the landing of the Chang’e lander, a laser 3D imaging sensor (L3DIS) is used to measure and generate accurate topographic maps of the candidate landing area in real-time to help find a safe landing zone. The L3DIS employs 16 beamlets split from a Gaussian laser beam and 16 channels of linear-array avalanche photodiodes within the same optical path and scans the object with a two-axis galvanometer in a field of view of 29°×33°. The calibration of the systematic errors and the performance of obstacle detection on this sensor are conducted in this paper. First, the instrument components and main error sources of the sensor are introduced, and the systematic errors are calibrated based on planar targets, indicating that the sensor’s accuracy is greater than 4 cm, and the corresponding obstacle detection accuracy is better than 12 cm. Second, the ground validation of obstacle detection is demonstrated, and the obtained point cloud is compared with that obtained by a terrestrial laser scanner, indicating that the sensor has good performance. Finally, the performance of onboard measurement and obstacle detection is analyzed, showing that the sensor can identify obvious craters and rocks, i.e., nine major craters with a maximum and minimum depth of 1.36 m and 0.16 m, respectively, and major rocks with a maximum and minimum height of 0.1 m and 0.05 m, respectively, and main landing area with slop less than 10° except for the edges of craters and rocks.

AI-based derivation of atrial fibrillation phenotypes in the general and critical care populations

Atrial fibrillation (AF) is the most common heart arrhythmia worldwide and is linked to a higher risk of mortality and morbidity. To predict AF and AF-related complications, clinical risk scores are commonly employed, but their predictive accuracy is generally limited, given the inherent complexity and heterogeneity of patients with AF. By classifying different presentations of AF into coherent and manageable clinical phenotypes, the development of tailored prevention and treatment strategies can be facilitated. In this study, we propose an artificial intelligence (AI)-based methodology to derive meaningful clinical phenotypes of AF in the general and critical care populations. Our approach employs generative topographic mapping, a probabilistic machine learning method, to identify micro-clusters of patients with similar characteristics. It then identifies macro-cluster regions (clinical phenotypes) in the latent space using Ward's minimum variance method. We applied it to two large cohort databases (UK-Biobank and MIMIC-IV) representing general and critical care populations. The proposed methodology showed its ability to derive meaningful clinical phenotypes of AF. Because of its probabilistic foundations, it can enhance the robustness of patient stratification. It also produced interpretable visualisation of complex high-dimensional data, enhancing understanding of the derived phenotypes and their key characteristics. Using our methodology, we identified and characterised clinical phenotypes of AF across diverse patient populations. Our methodology is robust to noise, can uncover hidden patterns and subgroups, and can elucidate more specific patient profiles, contributing to more robust patient stratification, which could facilitate the tailoring of prevention and treatment programs specific to each phenotype. It can also be applied to other datasets to derive clinically meaningful phenotypes of other conditions. This study was funded by the DECIPHER project (LJMU QR-PSF) and the EU project TARGET (10113624).

Plants, fungi, and carabid beetles in temperate forests: both observed and dark diversity depend on habitat availability in space and time

ContextThe loss of ancient forests threatens many species. Effective nature conservation needs information on how forest availability in the surrounding landscape in space and time determines the diversity of multiple taxa.ObjectivesWe explored the relationship between forest availability at different spatiotemporal scales and the diversity of various groups: vascular plants (woody species, ground layer), epiphytes (bryophytes and lichens), fungi (ectomycorrhizal, arbuscular mycorrhizal, pathogenic, saprotrophic), and carabid beetles. Besides the observed diversity, we also estimated dark diversity, i.e. suitable but absent species. Dark diversity is theoretically a sensitive metric in detecting ecosystem conditions as it is typically relatively large and contains susceptible species.MethodsWe recorded the observed diversity by field sampling and soil DNA in 100 temperate ancient old-growth forest sites in southern Estonia; dark diversity was estimated for the same sites using species co-occurrence data. Forest availability estimates were obtained from four topographic maps (1900s-2010s) at the 0.5–5 km radius.ResultsThe biodiversity of forest specialists was higher at larger historical forest availability at the spatial scale of 2–5 km radius. The diversity of light-demanding forest ecotone taxa mainly had negative relationships with young forests on previous agricultural lands (at 0.5–2 km radius). Dark diversity models were often more strongly associated with forest availability than observed diversity models.ConclusionsDark diversity enhances our understanding of how current and historical forest availability affects local biodiversity. As young forests cannot provide suitable habitats for many forest-dwelling species, stable forest habitats must be preserved as source areas to enhance biodiversity.

Spatial Evaluation of Waste Disposal Site Selection Using GIS-Based Multi-Criteria Analysis: A Case Study of Dera Ghazi Khan District, Pakistan

The rapid population growth and rising per capita incomes have caused the city to generate massive amounts of municipal waste, indicating a serious environmental threat. Solid waste disposal has become a crucial problem for several municipalities. The selection of suitable waste disposal sites is a crucial problem in the urban areas of developing countries like Pakistan due to unsatisfactory urban planning and management to decrease human being’s health risks. Particularly, Dera Ghazi (D.G.) Khan district is facing the issue of identifying suitable sites for solid waste disposal. This research aims to select appropriate potential sites suitable for solid waste disposal purposes in the D.G. Khan. Primary datasets used for this study are Landsat-8 satellite imagery, digital elevation model (DEM) with 30-meter resolution for slope extraction. Other criteria included roads, railroads, and rivers digitized using the topographical map of the study area. The maps are prepared to incorporate overlay and suitability analysis using Geographic Information System (GIS), Remote Sensing techniques, and Analytical Hierarchy Process (AHP), a multi-criteria analysis. The final suitability map of study area is prepared using a GIS software suite and categorized as highly, moderately, least, and unsuitable regions, of which 3% is entirely unsuitable area, 70% less suitable, 26.16% moderately suitable, and 0.84% highly suitable area. The suggested disposal sites have been carefully selected to assist policymakers in determining the most sensitive areas and resolving waste management issues with the slightest contamination of water bodies and the environment.