Geodesy and Geomatics Engineering Technical Reports

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A Marine recreational vessel reconnaissance system utilizing IKONOS imagery
A Marine recreational vessel reconnaissance system utilizing IKONOS imagery
This dissertation investigates the ability of IKONOS imagery to detect small recreational boats. To accomplish this, automatic target detection software called MRV Recon has been developed which makes use of a weighted Euclidean distance metric. To test the detection accuracy of MRV Recon, a dataset was created by gathering position and attribute data for 53 recreation vessel targets within Cadboro Bay, British Columbia, Canada. IKONOS imagery was collected in May 2003. The overall detection accuracy was 77 %. The targets were broken down into two categories: A) less than 6 m in length, and B) greater than 6 m long. The detection rate for the category B targets was 100%, while the detection rate for the category A targets was 61%. It is important to note that some category A targets were selected specifically to test the detection limits of MRV Recon. The smallest target detected was 2.2 m long and 1.1 m wide. The analysis also revealed that the ability to detect targets between 2.2 m and 6 m long was diminished if the target was a dark colour. It has been demonstrated that MRV Recon will provide the Canadian Coast Guard with a unique and effective tool for gathering crucial data on recreational vessels.
A case study of the production of an S-57 ENC with CARIS tools
A case study of the production of an S-57 ENC with CARIS tools
The advent of the Electronic Chart Displaying and Information System (ECDIS) and the availability of an accurate positioning system, such as the Differential Global Positioning System (DGPS), were the driving technologies for a new digital hydrographic product. The Electronic Navigational Chart (ENC) is a new hydrographic product, recognized by the international marine instances as the equivalent of the traditional paper chart. The production of ENCs is being supported by the use of Geographic Information System (GIS) tools to meet the requirements of the International Standard for the Exchange of Hydrographic Data, documented in the IHO special publication No 57 (S-57). The S-57 document makes the use of the object-oriented concept to model the real world into a computer-based format. The aim of this report is to study the production of an ENC with tools from Universal Systems Limited (USL), CARIS and OBMAN, to make recommendations and suggestions not only for software enhancement but also to contribute to the optimization procedures within an Hydrographic Office (HO) currently producing both paper and electronic charts. This report is structured in seven chapters. This first two define the problem of building an ENC within an HO and introduce an historical background to support the discussion between raster and vector charts. The Object-Oriented (O-O) concept in general and its meaning for the S-57 standard, in particular, is described in chapter 3. The use of “dedicated methods” in O-O is particularly important within the S-57 ENC because it allows an object to be displayed with different geometries depending on the scale chosen. The S-57 standard is explained in detail in chapter 4, while chapter 5 introduced the CARIS tools used. Chapter 5 also compares two different ENC viewers (ECVIEW and SeeMyENC!). The steps followed by the author to build an S-57 ENC are also contained in this chapter. An example is the need for an appropriate layering of the data whenever a CARIS file is built for both paper and electronic chart production. The author also suggests a quality control tool to check for inconsistences and distortions on the shapes of the feature objects after the filtering of the point data (S-57 standard).
A comparison of local and wide area GNSS differential corrections disseminated using the network transort of RTCM via internet protocol (NTRIP)
A comparison of local and wide area GNSS differential corrections disseminated using the network transort of RTCM via internet protocol (NTRIP)
Psuedorange corrections (PRCs) have long been used to improve the accuracy of GNSS solutions in real time. Today, they continue to be useful for sub-metre level requirements, such as when setting ground control for satellite imagery and for en route navigation on land, in the air and at sea. The transmission of these corrections has traditionally been facilitated using either radio or satellite communications. The Networked Transport of RTCM via Internet Protocol (NTRIP) specification takes advantage of the availability of Internet over digital mobile phones to disseminate PRCs. In this report, NTRIP has been used to transmit both localized wide area and local PRC corrections over the Internet to a client receiver where they have been applied. The accuracy of different solutions is compared. In addition, the convergence of different solutions is analyzed. This analysis will enable potential users to determine the position and height accuracy that they can expect to achieve under various scenarios as well as the observation times which they should employ. Results for horizontal positions showed errors at a 95% confidence level to be at the 2-metre level for uncorrected GNSS, 30 cm for GNSS augmented with local corrections generated at UNB and 1.0 m for corrections generated 430 km away. The Canadawide Differential GPS (CDGPS) wide area system produced errors of 60 cm. Results for heights were of a similar order. However, we found that height solutions were significantly more correlated with observation time than were horizontal positions. Our work showed that NTRIP could be used easily to both disseminate and use localized wide area and local differential corrections. We believe that as costs for digital mobile service becomes cheaper and more widely available, NTRIP will become commonly used. In addition, we recommend that the CDGPS service consider supporting NTRIP. Currently, CDGPS has a limited user-base because it is accessible only with the use of receivers containing NovAtel®-based chipsets. We believe that NTRIP can potentially bring CDGPS to a much wider object. Finally, by far, the best position and height accuracies achieved were with the use of local differential corrections. Even when the reference receiver was 430 km from the user receiver, resulting solutions were better in both accuracy and precision than uncorrected solutions. Canada and New Brunswick each operate an Active Control Network, consisting of many continuously operating GNSS receivers that are already connected to the Internet. We believe that with very little effort, this network can be extended, using NTRIP, to disseminate DGNSS corrections.
A digital data recorder and transfer device for the MARCONI 722B Satellite Navigation Receiver
A digital data recorder and transfer device for the MARCONI 722B Satellite Navigation Receiver
Dr. David Wells of the Department of Surveying Engineering uses a MARCONI 722B Satellite Navigation Receiver in his research. At present, data output from this device is recorded using a paper tape punch. The paper tape produced from the punch is then fed into the IBM 3032 at the U.N.B. Computing Center for calculations and analysis. Needless to say, this methods has proved to be somewhat awkward and cumbersome. The aim of this project is to provide a convenient alternative to the current system, using a micro-computer to collect data directly from the satellite receiver, and then transfer this data to the IBM 3032 through the VSPC online terminal system.
A geospatial web application (GEOWAPP) for supporting course laboratory practices in surveying engineering
A geospatial web application (GEOWAPP) for supporting course laboratory practices in surveying engineering
Although most of the university courses are somehow supported by a Learning management system (e.g Desire2Learn), field practices in survey engineering are not interactively supported by these systems. Also, the internet is available in almost every place today, and there are a wide range of internet services on the web. By combining these advantages with e-learning, survey practicums can be enhanced with a web-based application. The survey practicums are very specialized with precise traditional techniques used for checking measurements in the field. Thus, the combination of E-learning and practicums is not straight forward. In order to achieve this combination, there is a need to define a framework of survey exercises and a way of effectively delivering the information to the student making the process more efficient. Different outlines of surveying courses were studied in order to provide a set of exercises that can be supported by a GEOWAPP (Geospatial Web Application). This thesis proposes a combination of processing tools, created in Python, JavaScript and PHP, and Google Maps. The main objectives is to enhance the experiences that students have in the field as well as evaluating their techniques for surveying. Accuracy was chosen as the pillar of this application, which helps to gather information about students technique and computations, and to locate students’ mistakes easily. This specific application is intended for self-reviewing. A prototype of the application was developed, which contains five (5) operational tools. These tools were tested with artificial and real data; this testing gave a good insight of such an application requirements. User reviews were carried out showing that students embrace the idea of similar applications. Finally, GEOWAPP showed some learning enhancing characteristics. However, a test with a real course remains to be carried out to determine whether it is beneficial to students.
A land information network for New Brunswick
A land information network for New Brunswick
Concern about regional economic disparity and the need to make the best possible use of resources has spurred New Brunswick to place its land information management on a formal and systematic basis. Interest in utilizing land information in decision making processes is leading to the development of land information system in the province. A land information system may be defined as a combination of human and technical resources, together with a set of organizing procedures, which results in the collection, storage, retrieval, dissemination, and use of land information in a systematic fashion. Land information systems may be classified according to the nature of the information managed. This gives, for example: a) environmental information which is concerned with environmental zones of unique physical, biological, or chemical natures. b) infrastructure information which relates to man-made improvements to the land. c) cadastral information which focuses on rights, restraints, and responsibilities associated with the land. d) socio-economic information which is concerned with human and economic geography. There distinctions, however, are by no means clear cut. Most recently, attention has been focused on improving coordination between systems through a land information network. A network may be described as a confederation of land information systems. While a land information system may be regarded as an attempt to improve the effective flow of information within an organization, a land information network may be viewed as an attempt to improve the effective flow of information between organizations. A land information network requires information exchange standards and special co-ordination mechanisms. It also requires an understanding of the functions and needs of the land information community. A land information network is characterized by heterogeneity. It brings together people of different background, needs, and beliefs. It utilizes technology in widely disparate forms. A long term commitment by a multi-disciplinary team of land information managers is required if the individual heterogeneous elements are to be melded into a cohesive unified whole.
A least squares adjustment for long baseline interferometry
A least squares adjustment for long baseline interferometry
Long baseline interferometry software and data, developed by the Canadian L.B.I. group at York University has been combined with a least squares adjustment package. The options have been implemented to accept an input of both weighted parameters and functional parameter constraints. The results are then analysed statistically, including a chi-square goodness-of-fit test in residuals, a rejection criteria for residual outliers, and chi-square test on the variance factor. The package has been developed with closer regard to computer economy. Computer storage space has been reduced by 60% and processing time has been reduced by 96% compared with the previously used maximum likelihood adjustment routines. This increase in efficiency has resulted in an ability to input a larger number of observations and, accordingly, in an improvement in accuracy.
A long arc approach to GPS satellite orbit improvement
A long arc approach to GPS satellite orbit improvement
The object of this thesis was to design a model, implement software, and test the model and the software for improving the accuracy of the orbits of the satellites of the Navstar Global Positioning System (GPS) using double difference GPS phase observation. A dynamic long arc approach is used and satellite orbits are integrated continuously over multiple days. The model includes: The coordinate system transformation between the geocentric inertial coordinate system and the Earth-fixed coordinate system; the modelling of the forces acting on the GPS satellites; the integration methods for the solution of the equations of motion for the GPS satellites, and the partial derivatives of the satellite position vectors with respect to initial state vectors and dynamical parameters; the designation of unknown parameters which are solved for in data processing; the handling of biases in GPS observations; and the adjustment and computational algorithm. A software package associated with the above model has been developed for the Macintosh computer family. The software development is partially based on the GPS Differential Positioning Program (DIPOP) package of the Department of Surveying Engineering of the University of New Brunswick, and the new software package is called DIPOP-E (Enhanced version of DIPOP). The main-processor of DIPOOP-E differs the new version, although DIPOP-E inherits most of the features of the main-processor in DIPOP; the pre-processor has been modified only to accommodate new features in the main-processor, and to improve operational efficiency for processing large data sets. A new special utility tool has been developed for the cycle slip detection and correction. The tool uses window, menu, button, mouse, and graphic display features of the Macintosh computer, which greatly enhances the operational efficiency of the package. Other auxiliary programs have been developed to facilitate the use of the main-processor. The model and software development have been tested thoroughly with the Standard GPS Data Set of the International Association of Geodesy Special Study Group 1.104. All test show that the most accurate results were for the latitude components, followed by the baseline lengths, the longitude components, and finally height components. This [phenomenon is due to the sky distribution of the GPS satellites. The optimistic results of formal uncertainties show that there are some remaining systematic biases in the model. The daily repeatabilities show that the latitude component and baseline length determination were mostly better than 0.1 ppm. For the regional and continental stations, 0.05 ppm level repeatabilities were achieved for the lengths of baselines. The worse results for the short baselines (in terms of ppm) and for the height components may be due to the residual tropospheric effects as no observed meteorological data have been used in data processing.

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