scholarly journals Solving Monocular Visual Odometry Scale Factor with Adaptive Step Length Estimates for Pedestrians Using Handheld Devices

Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 953 ◽  
Author(s):  
Nicolas Antigny ◽  
Hideaki Uchiyama ◽  
Myriam Servières ◽  
Valérie Renaudin ◽  
Diego Thomas ◽  
...  
Keyword(s):  
Pose Estimation ◽  
Geographical Information Systems ◽  
Digital Terrain Model ◽  
Visual Odometry ◽  
Step Length ◽  
Geographical Information ◽  
Handheld Devices ◽  
Measurement Unit ◽  
Handheld Device ◽  
Adaptive Step

The urban environments represent challenging areas for handheld device pose estimation (i.e., 3D position and 3D orientation) in large displacements. It is even more challenging with low-cost sensors and computational resources that are available in pedestrian mobile devices (i.e., monocular camera and Inertial Measurement Unit). To address these challenges, we propose a continuous pose estimation based on monocular Visual Odometry. To solve the scale ambiguity and suppress the scale drift, an adaptive pedestrian step lengths estimation is used for the displacements on the horizontal plane. To complete the estimation, a handheld equipment height model, with respect to the Digital Terrain Model contained in Geographical Information Systems, is used for the displacement on the vertical axis. In addition, an accurate pose estimation based on the recognition of known objects is punctually used to correct the pose estimate and reset the monocular Visual Odometry. To validate the benefit of our framework, experimental data have been collected on a 0.7 km pedestrian path in an urban environment for various people. Thus, the proposed solution allows to achieve a positioning error of 1.6–7.5% of the walked distance, and confirms the benefit of the use of an adaptive step length compared to the use of a fixed-step length.

Automated hydrologic analysis of ungauged basins in Serbia using open source software

2014 ◽  
Vol 9 (4) ◽  
pp. 445-449
Author(s):  
N. Zlatanović ◽  
M. Stefanović ◽  
M. Milojević ◽  
J. Čotrić
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
Geographical Information Systems ◽  
Digital Terrain Model ◽  
Geographical Information ◽  
Ungauged Basins ◽  
Small Hydropower ◽  
Protection Measures ◽  
Hydropower Plants ◽  
Discharge Estimation

Drainage basins are for the most part ungauged or poorly gauged not only in Serbia but in most parts of the world, usually due to insufficient funds, but also the decommission of river gauges in upland catchments to focus on downstream areas which are more populated. Design discharges are needed for these rivers where no streamflow data are available, for various applications. Examples include river training works for flood protection measures or erosion control, design of culverts, water supply facilities, small hydropower plants, etc. This study deals with the application of freely available and open source software and datasets for automating rainfall–runoff analysis of ungauged basins, applying geographical information systems techniques and programming to methodologies currently in use in hydrological practice. The geomorphometric module was tested on more than 100 catchments throughout Serbia (using a digital terrain model) and compared to manually calculated values (using topographic maps). The discharge estimation module was tested on 21 catchments where data were available and compared to results obtained by frequency analysis of measured discharges. The geomorphometric module of the calculation system showed excellent results, saving a great deal of time that would otherwise have been spent on manual processing of geospatial data, while the discharge estimation module showed a need for improved hydrological models.

scholarly journals Pedestrian Dead Reckoning Navigation with the Help of A⁎-Based Routing Graphs in Large Unconstrained Spaces

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
F. Taia Alaoui ◽  
David Betaille ◽  
Valerie Renaudin
Keyword(s):  
Dead Reckoning ◽  
Step Length ◽  
Magnetic Sensors ◽  
Handheld Devices ◽  
Indoor Environments ◽  
Handheld Device ◽  
Proposed Model ◽  
Seamless Transition ◽  
Gyro Drift ◽  
Indoor And Outdoor

An A⁎-based routing graph is proposed to assist PDR indoor and outdoor navigation with handheld devices. Measurements are provided by inertial and magnetic sensors together with a GNSS receiver. The novelty of this work lies in providing a realistic motion support that mitigates the absence of obstacles and enables the calibration of the PDR model even in large spaces where GNSS signal is unavailable. This motion support is exploited for both predicting positions and updating them using a particle filter. The navigation network is used to correct for the gyro drift, to adjust the step length model and to assess heading misalignment between the pedestrian’s walking direction and the pointing direction of the handheld device. Several datasets have been tested and results show that the proposed model ensures a seamless transition between outdoor and indoor environments and improves the positioning accuracy. The drift is almost cancelled thanks to heading correction in contrast with a drift of 8% for the nonaided PDR approach. The mean error of filtered positions ranges from 3 to 5 m.

Assessment of land-use change in coastal areas through geographical information systems

2020 ◽  
Vol 13 (10) ◽  
Author(s):  
Verónica Lango-Reynoso ◽  
Karla Teresa González-Figueroa ◽  
Fabiola Lango-Reynoso ◽  
María del Refugio Castañeda-Chávez ◽  
Jesús Montoya-Mendoza
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Geographical Information Systems ◽  
Design Methodology ◽  
Scientific Information ◽  
Coastal Ecosystems ◽  
Coastal Areas ◽  
Geographical Information ◽  
Coastal Zones ◽  
Computer Based

Objective: This article describes and analyzes the main concepts of coastal ecosystems, these as a result of research concerning land-use change assessments in coastal areas. Design/Methodology/Approach: Scientific articles were searched using keywords in English and Spanish. Articles regarding land-use change assessment in coastal areas were selected, discarding those that although being on coastal zones and geographic and soil identification did not use Geographic Information System (GIS). Results: A GIS is a computer-based tool for evaluating the land-use change in coastal areas by quantifying variations. It is analyzed through GIS and its contributions; highlighting its importance and constant monitoring. Limitations of the study/Implications: This research analyzes national and international scientific information, published from 2007 to 2019, regarding the land-use change in coastal areas quantified with the digital GIS tool. Findings/Conclusions: GIS are useful tools in the identification and quantitative evaluation of changes in land-use in coastal ecosystems; which require constant evaluation due to their high dynamism.

A protocol for sampling pastures in hill country

2016 ◽  
Vol 78 ◽  
pp. 203-209 ◽  
Author(s):  
K.J. Hutchinson ◽  
D.R. Scobie ◽  
J. Beautrais ◽  
A.D. Mackay ◽  
G.M. Rennie ◽  
...  
Keyword(s):  
Random Sampling ◽  
Geographical Information Systems ◽  
Field Measurements ◽  
Decision Support Tool ◽  
Accurate Estimate ◽  
Ease Of Use ◽  
Geographical Information ◽  
Support Tool ◽  
Topographic Complexity ◽  
Hill Country

To develop a protocol to guide pasture sampling for estimation of paddock pasture mass in hill country, a range of pasture sampling strategies, including random sampling, transects and stratification based on slope and aspect, were evaluated using simulations in a Geographical Information Systems computer environment. The accuracy and efficiency of each strategy was tested by sampling data obtained from intensive field measurements across several farms, regions and seasons. The number of measurements required to obtain an accurate estimate was related to the overall pasture mass and the topographic complexity of a paddock, with more variable paddocks requiring more samples. Random sampling from average slopes provided the best balance between simplicity and reliability. A draft protocol was developed from the simulations, in the form of a decision support tool, where visual determination of the topographic complexity of the paddock, along with the required accuracy, were used to guide the number of measurements recommended. The protocol was field tested and evaluated by groups of users for efficacy and ease of use. This sampling protocol will offer farmers, consultants and researchers an efficient, reliable and simple way to determine pasture mass in New Zealand hill country settings. Keywords: hill country, feed budgeting, protocol pasture mass, slope

Geoinformation research and vegetation mapping (digest based on the proceedings of the InterCarto. InterGIS conference. 1994–2020)

2020 ◽  
pp. 78-98
Author(s):  
T. V. Kotova
Keyword(s):  
Forest Management ◽  
Environmental Sustainability ◽  
Geographical Information Systems ◽  
Biological Diversity ◽  
Far East ◽  
Vegetation Mapping ◽  
Geographical Information ◽  
Plant Resources ◽  
Ecological Functions ◽  
Geoinformation Technologies

Proceedings of the International conference (ИнтерКарто. ИнтерГИС, Russia) devoted to geographical information systems for sustainable development of territories have been published annually since 1994. The articles discuss theoretical and methodological aspects of geoinformation support for environmental, economic and social aspects of sustainable de­velop­ment, issues of geoinformatics, cartography, remote sensing of the Earth, problems of environmental sustainability and environmental impact assessment. Over a quarter of a century, the conference proceedings got more than 125 articles related to the use of geoinformation technologies to the study and mapping of vegetation. The review of proceedings gives the concrete examples how to solve problems of vegetation mapping using GIS, it is focused on publications providing some examples of GIS appli­cation to the vegetation studies. The review is organized into thematic sections according the field of application of Geoinformatics: 1.Vegetation, 2. Dynamics, state and ecological functions of vegetation, 3. Biodiversity and its assessment, 4. Plant resources, 5. Monitoring of vegetation. The Vegetation section contains publications on vegetation studies and mapping performed for some regions of Russia — the North of the Far East, the Republic of Sakha (Yaku­tia), the Tyva Republic, Central Siberia, and others. More than half of the articles are devoted to vegetation dynamics, state and ecological functions of vegetation at different hierarchical levels. Some papers present the results of the studies based on new types of information sources (photographs) and visualization methods (animation). The use of geoinformation technologies to study biological diversity was included in the agenda of five conference sessions and later reflected in more than ten publications. They cover the development and creation of GIS, the use of geoinformation technologies for the analysis, assessment and mapping of biodiversity, for its monitoring and conservation. Quite a large number of articles are devoted to the study of forest resources. GIS technologies were used to solve problems of forest management, cartometric analysis of forested areas, determination of taxation indicators, systematization of forest conditions, etc. Examples of geoinformation versatile research for medicinal plant resources are given to assess their quality, resources and productivity in the region, to identify growing areas, including ones to be protected. Most of the published materials concerning to vegetation monitoring mainly relate to forests and forest management.

PROBLEMATIC ISSUES OF THE GEOGRAPHIC INFORMATION SYSTEMS USE IN SOCIO-HYGIENIC MONITORING AND RISK-BASED SUPERVISION

2019 ◽  
pp. 31-36 ◽  
Author(s):  
Е.М. Studenikina ◽  
Yu.I. Stepkin ◽  
O.V. Klepikov ◽  
I.V. Kolnet ◽  
L.V. Popova
Keyword(s):  
Information Systems ◽  
Technology Implementation ◽  
Geographical Information Systems ◽  
Geographical Information ◽  
Electronic Library ◽  
Information Portal ◽  
Software Products ◽  
Stage Of Development ◽  
Software Product ◽  
Information Systems Use

The paper considers the problematic issues of the geographical information systems (GIS) use in the sociohygienic monitoring (SHM). We analyzed scientific and practical publications on this subject that are freely available on the largest Russian information portal of scientific electronic library eLIBRARY.RU during 2014- 2018, which allowed us to formulate the principles of organization and requirements for effective operation of geographic and information systems in the socio-hygienic monitoring. An analysis of the implementation of these principles at the present stage of development for the socio-hygienic monitoring system is presented, the results of which were used in formulating priority tasks in the area of geographic and information technology implementation into socio-hygienic monitoring and risk-based planning of control and supervisory measures: to determine the necessary level of detail and an information list depicted on electronic maps for the implementation of risk-based control planning; to provide organizational and regulatory and methodological support for the hierarchical principle of GIS within Rospotrebnadzor operating on a single software product of domestic developers for organizations and institutions; to work out the need to combine GIS with similar systems of other departments involved in the data collection of social and hygienic monitoring (Rosstat, Roshydromet, Rosprirodnadzor, Ministry of Health, etc.) to enable automated data export and import; to solve staffing issues to ensure customization and subsequent GIS operation; to provide budget funding for the purchase of licensed software products for GIS in SHM, preferably of Russian developers.

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