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Linear features (e.g., roads, rivers), outlines of areas (e.g., municipal boundaries, lake banks) or mov ing objects' trajectories (e.g., humans, vehicles) are represented on paper or digital maps with polyline geometries. Sampling, discretization and generalization processes result in polylines represented by a subset of vertices of the original line. The simplified version of a linear feature may violate some spatial relations (topological, direction or distance) that apply between the original line and some other objects in space, unless a model that considers the context of the neighbouring space is applied. The latter turns the line sim plification into a rather complicated and challenging-to-automate process. This paper introduces a method that supports a consistent line simplification without considering the context of the neighbouring space. The method applies well-known geo-processing tasks, such as polyline-to-raster and raster-topoly l ine conversions, and is compliant with the raster tiled maps as well as the discrete global grid systems. [ABSTRACT FROM AUTHOR]

The article focuses on management of law and regulations related to geospatial data related to geomatics community. Topics discussed include concern over preservation of intellectual property (IP) over collection of geospatial data; infringement of copyright issues of land surveyors; observation of lawsuit by Geophysical Service against Encana regarding seismic data collection; and significance of decision making in management of industrial standards.

The article offers news briefs related to geomatics field in Canada as of June 2016. Topics discussed include introduction of next generation the Altus APS3G Real Time Kinematic (RTK) receivers by satellite receivers maker Septentrio; production of sky-scanner LiDAR image collection by geomatic firm Siteco Informatica for unmanned aerial vehicles (UAVs); and observation of monumental structure at ancient city Petra that is analysed through satellite imagery.

The article announces the David Thompson National Geomatics Awards that includes the Innovation in Geomatics to Ryan Schuler of land surveyor firm Sub - Arctic Surveys; the Challenging Applications in Cadastral Surveying to Paul Dixon; and the Contribution to Society to Ryan Schuler.

The article discusses the boundary tribunal for aboriginal lands, the Specific Claims Tribunal proposed in 1947 by the Special Joint Committee of the Senate and House of Commons and ruling of the court in the case Godfrey v Ontario affirming a decision pursuant to Ontario Boundaries Act.

The article discusses geomatics, a branch of science related to earth's surface, environmental negligence and professional misconduct with a particular focus on two court cases of an engineer and land surveyor explaining the activities falling under misconduct and negligence.

The article focuses on government actions related to geomatics in Canada from 2011 to 2015.

An introduction is presented to a section on college and university programs on geomatics and geography in Canada.

The article offers world news briefs related to geomatics. The topics discussed include the release of the ADC WorldMap Digital Atlas v7.1 by the American Digital Cartography Inc., the Seventh international users conference organized by Trimble Navigation Ltd., and the release of the interactive map that details the history of Ebola outbreak worldwide.

Corporations, government agencies, educational organizations and associations with an interest in the activities of the Canadian Institute of Geomatics are eligible to become Sustaining Members of the Institute. [ABSTRACT FROM AUTHOR]

Monitoring aquatic vegetation is an important component of water resource management due to the ecological services provided by these habitats. Spectrally-rich hyperspectral imagery can be an efficient tool for mapping and classifying macrophyte communities. Identification of submerged vegetation in aquatic regions is complicated by variations in optical properties of water constituents, sun-water-sensor geometry, water depth and the spectral/structural complexity of the plants. Many studies have attempted to detect aquatic vegetation in coastal waters; however, few studies have targeted shallow, black-water rivers tainted with chromophoric dissolved organic matter (CDOM). This study investigates methods to analyze airborne hyperspectral imagery and detect and classify aquatic vegetation in a black-water riverine system. Images were normalized to account for reflectance from the water surface and varying water depth before being analyzed by the Maximum Likelihood (ML) and three other non-parametric classifiers: Artificial Neural Network (ANN), Support Vector Machine (SVM) and Spectral Angular Mapper (SAM). Quality assessment analysis indicated a general classification and detection accuracy improvement when non-parametric classifiers were applied on the normalized and depth invariant images. A maximum classification accuracy of about 69% was achieved when the ANN classifier was applied on the normalized images, and maximum detection accuracies of 93% and 92% were obtained when the SAM and the SVM classifiers were applied on depth invariant images, respectively. [ABSTRACT FROM AUTHOR]

The article presents the profiles of the nonprofit organization Canadian Institute of Geomatics sustaining members. Among the sustaining members of the association are Intergraph Canada Ltd., Department of Geomatics Engineering, CanadianGIS.com, Association of Canada Lands Surveyors, and the EcoInformatics International Inc.

This paper investigates the hierarchical structures of 29 selected European countries from the perspective of blocks and natural cities and makes an across-country comparison among the countries. Blocks are minimum cycles consisting of road segments in the road network of a whole country; natural cities are defined as the aggregations of small blocks. We test the size distributions of blocks and natural cities at the country level and find that both exhibit heavy-tailed distributions. The power law distribution of city sizes indicates the presence of the scaling property. Therefore, the cities in a country can be repeatedly grouped into a similar two-tier structure of head and tail via the head/tail division rule. The ascending tiers represent the small, medium, large and mega cities. Accordingly, a simple model is developed to evaluate and cross compare the degree of similarity and stability of the scaling properties and hierarchical structures of cities. Moreover, cities and blocks are the functional units of a country, and the correlation coefficient values between city sizes/number of blocks and economic factors (i.e., gross domestic product and population) are up to 0.87. We further conjecture that the compared results of hierarchies can serve as an indicator to assess a country's economic system. [ABSTRACT FROM AUTHOR]

We develop a new precise point positioning (PPP) model for combined GPS/Galileo single-frequency observations. Both un-differenced and between-satellite single-difference (BSSD) modes are considered. Although it improves the solution availability and accuracy, combining GPS and Galileo observables introduces additional biases that must be modelled. These include the GPS-to-Galileo time offset and the inter-system bias. Additionally, to take full advantage of the Galileo E1 signal, it is essential that its stochastic characteristics are rigorously modelled. In this paper, various sets of GPS and Galileo measurements collected at two stations with short separation were used to investigate the stochastic characteristics of Galileo E1 signal. As a by-product, the stochastic characteristics of the legacy GPS P1 code were obtained and then used to verify the developed stochastic model of the Galileo signal. It is shown that sub-decimeter level accuracy is possible through our single-frequency GPS/Galileo PPP model. As well, the addition of Galileo improves the PPP solution convergence by about 30% in comparison with the GPS-only solution. Furthermore, the performance of BSSD GPS/Galileo PPP model was found comparable to that of the un-differenced counterpart. [ABSTRACT FROM AUTHOR]

The understanding of the effects of error on Mobile Terrestrial LiDAR (MTL) point clouds has not increased with their popularity. In this study, comprehensive error analyses based on error propagation theory and global sensitivity study were carried out to quantitatively describe the effects of various error sources in a MTL system on the point cloud. Two scenarios were envisioned; the first using the uncertainties for measurement and calibration variables that are normally expected for MTL systems as they exist today, and the second using an ideal situation where measurement and calibration values have been well adjusted. It was found that the highest proportion of error in the point cloud can be attributed to the boresight and lever arm parameters for MTL systems calibrated using non-rigours methods. In particular, under a loosely controlled error condition, the LiDAR to INS Z lever arm and the LiDAR to INS roll angle contributed more error in the output point cloud than any other parameter, including the INS position. Under tightly controlled error conditions, the INS position became the dominant source of error in the point cloud. In addition, conditional variance analysis has shown that the majority of the error in a point cloud can be attributed to the individual variables. Errors caused by the interactions between the diverse variables are minimal and can be regarded as insignificant. [ABSTRACT FROM AUTHOR]

Strategic decision-making is often based on multiple decision criteria and on the decision-makers' preferences regarding relative criterion importance. We present version 2 of a map overlay and opacity tool (moot2), which supports the visual exploration of decision-making scenarios. The tool uses a basic function of geographic information systems (GIS): visual map overlay. In this approach, visual overlay serves as a representation of weighted linear combination in multi-criteria decision analysis (MCDA). Using the tool, we model a global human influence index for the extent of the province of Ontario, Canada. The index is a weighted overlay of six indicators that represent human influence on the land. The semi-transparent overlay of the six indicator layers occurs online in a web browser, making it accessible to distant collaborators in low-technology settings. The software architecture of moot2 includes the OpenLayers JavaScript library to display thematic Web Map Service (WMS) layers, such as the human influence indicators, on top of popular base map services, such as OpenStreetMap or Google Maps. The tool also uses jQuery, a JavaScript library that enables interactions between the user and the map environment. Layer opacity is manipulated by the jQuery Slider, permitting the user to generate on-the-fly weighting schemes for the combination of the human influence indicators. By removing the analytical engine (i.e., GIS), decision-makers can perform rapid MCDA without recalculating composite evaluation scores. The case study demonstrates how visual-spatial MCDA supports the refinement of decision-making parameters such as criterion weights. [ABSTRACT FROM AUTHOR]

Geodetic-grade dual-frequency GPO receivers are typically used for precise point positioning (PPP). Unfortunately, these receiver systems are expensive and may not provide a cost-effective solution in many instances. The use of low-cost single-frequency GPO receivers, on the other hand, are limited by the effect of ionospheric delay. A number of mitigation techniques have been proposed to account for the effect of ionospheric delay for single-frequency GPO users. Unfortunately, however, those mitigation techniques are not suitable for PPP. More recently, the U.S. Total Electron Content (USTEC) product has been developed by the National Oceanic and Atmospheric Administration (NOAA), which describes the ionospheric total electron content in high resolution over most of North America. This paper investigates the performance of USTEC and studies its effect on single-frequency PPP solution. A performance comparison with two widely-used ionospheric mitigation models is also presented. [ABSTRACT FROM AUTHOR]

Over the past decade, network RTK technology has become popular as an efficient method of precise, real-time positioning. Its relatively low-cost and single receiver ease-of-use has allowed it to mostly replace static relative GPO and single baseline RTK in urban areas where such networks are economically viable (e.g., cadastral and construction survey). The Ministry of Transportation of Ontario (MTO) and York University have investigated the performance of commercial network RTK services in Southern Ontario, where performance is defined by a set of developed metrics. It was found that the user horizontal solution had an overall precision of ~2.5 cm (95%), though there were cases of solution biases, drifts and gaps. A follow-up study is developing criteria and pathways for the certification of such commercial network RTK services, focusing on: reference station integration, reference station maintenance, and user solution monitoring. A set of recommendations for network certification is in preparation. [ABSTRACT FROM AUTHOR]

Information on the topics discussed at the XXVI International Cartographic Conference held in Dresden, Germany on August 25-30, 2013 is presented. Topics include the national mapping approaches in the context of geomatics democratization, the 2011 acquisition of the 1507 Waldseemüller World Map, and the proposed International Map Year in 2015. The conference featured several experts in the field of cartography including Éric Loubier, Fenella France and Fraser Taylor.

The article discusses geomatics and the law in Canada. It explores the relevance of big data on business innovation and the geospatial market. It presents several cases involving the use of field notes to resolve rectilinear boundary issues including a case in Ontario where a court granted a statutory order prohibiting the defendant from engaging in the practice of cadastral surveying because of he is not a land surveyor.

The article offers information on various topics related to geomatics in Canada. Topics include editor Jim Jones' 1963 acquisition of certificates of Surveyor's Commissions held by surveyor Charles Alexander Magrath, a report from Quebec Land Surveyors' Board of Directors of the Corp. which highlight the important role of its members, and an article by K. M. Baird of the National Research Council about the foot as a fundamental unit of length used by surveyors.

Information on the topics discussed at the 2013 Canadian Institute of Geomatics (CIG) annual conference and the 2013 International Conference on Earth Observation for Global Changes (EOGC) held in Toronto, Ontario on June 5-7. Topics include geospatial image analysis and processing, remote sensing and geographic information system for snow and ice, and land use and land cover changes.