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1.
PREFACE The paper contains a brief overview of the professional activities of Professor Gottfried Konecny,Professor Emeritus at the Institute of Photogrammetry and GeoInformation,Leibniz University Hannover,Germany,and his influence on photogrammetry,remote sensing and geospatial infor-mation science during his time at the University of New Brunswick,Canada,and at the Leibniz University.His work can be divided into educational,scientific,application,organizational,and work in international societies.Additional activities comprised of giving courses in various languages,consultancy activities,and various other cooperations which took place in many South American countries,in Africa and Asia,for organizations such as the World Bank,United Nations,German Space Agency DLR,to name only a few.Activities in connection with international societies mainly took place during Prof.Konecny's engagement in the Council of the International Society for Photogrammetry(ISP),renamed the International Society for Photogrammetry and Remote Sensing(ISPRS),and the European Association of Remote Sensing Laboratories(EARSeL)Bureau.He was a key figure in bringing many countries and organizations to ISPRS as Ordinary and Sustaining Members.Professor Konecny has always been aware of the importance of international cooperation at various levels,also with sister societies such as the International Cartographic Association and the United Nations-Global Geospatial Information Management(UN-GGIM).His application activities span from the photogrammetry-oriented projects he was awarded in Canada,to remote sensing topics and geospatial sciences,combined with cartography during his Hannover period.His vision and endless effort are exemplary for a person who has always been devoted to the three geosciences mentioned above.Professor Konecny is the author of a number of books,journal papers and papers presented at international and national conferences.He has been a recognized keynote speaker at many conferences throughout the world due to his vast experience.This paper describes 75 years of a man who is an expert in fields which arose during his academic life.  相似文献   

2.
Abstract

A procedure for continental‐scale mapping of burned boreal forest at 10‐day intervals was developed for application to coarse resolution satellite imagery. The basis of the technique is a multiple logistic regression model parameterized using 1998 SPOT‐4 VEGETATION clear‐sky composites and training sites selected across Canada. Predictor features consisted of multi‐temporal change metrics based on reflectance and two vegetation indices, which were normalized to the trajectory of background vegetation to account for phenological variation. Spatial‐contextual tests applied to the logistic model output were developed to remove noise and increase the sensitivity of detection. The procedure was applied over Canada for the 1998‐2000 fire seasons and validated using fire surveys and burned area statistics from forest fire management agencies. The area of falsely mapped burns was found to be small (3.5% commission error over Canada), and most burns larger than 10 km2 were accurately detected and mapped (R2 = 0.90, P<0.005, n = 91 for burns in two provinces). Canada‐wide satellite burned area was similar, but consistently smaller by comparison to statistics compiled by the Canadian Interagency Forest Fire Centre (by 17% in 1998, 16% in 1999, and 3% in 2000).  相似文献   

3.
《测量评论》2013,45(12):352-357
Abstract

Preliminary Note.—The substance of this article was written in 1921 at the request of Lieut-Col. Wolff, who was then in charge of the Levelling Division of the Ordnance Survey and with whom the author collaborated in writing “The Second Geodetic Levelling of England and Wales, 1912–21” under the direction of Sir Charles Close. It was not intended for publication and was not again considered until 1928, when a discussion by correspondence was started by the Surveyor-General of Ceylon on the subject of hill circuits in levelling. In this discussion the survey authorities in Great Britain, Canada, India, and South Africa took part, but the main theme was the accumulation of error due to the large number of sightings necessary in hilly country and the question whether a common formula for such country and for flat country was justifiable. In his contribution Dr. van der Sterr made a brief allusion to the subject of the present paper and Dr. de Graaff Hunter went into details. His contribution and the following remarks therefore have some arguments in common.  相似文献   

4.
Agriculture plays a critical role within Canada’s economy and, as such, sustainability of this sector is of high importance. Targeting and monitoring programs designed to promote economic and environmental sustainability are a vital component within Canada’s agricultural policy. A hierarchy of land information, including up to date information on cropping practices, is needed to measure the impacts of programs on land use decision-making and to gauge the environmental and economic benefits of these investments. A multi-year, multi-site research activity was completed to develop a robust methodology to inventory crops across Canada’s large and diverse agricultural landscapes. To move towards operational implementation the methodology must deliver accurate crop inventories, with consistency and reliability. In order to meet these operational requirements and to mitigate risk associated with reliance on a single data source, the methodology integrated both optical and Synthetic Aperture Radar (SAR) imagery. The results clearly demonstrated that multi-temporal satellite data can successfully classify crops for a variety of cropping systems present across Canada. Overall accuracies of at least 85% were achieved, and most major crops were also classified to this level of accuracy. Although multi-temporal optical data would be the preferred data source for crop classification, a SAR-optical dataset (two Envisat ASAR images and one optical image) provided acceptable accuracies and will mitigate risk associated with operational implementation. The preferred dual-polarization mode would be VV–VH. Not only were these promising classification results repeated year after year, but the target accuracies were met consistently for multiple sites across Canada, all with varying cropping systems.  相似文献   

5.
In the Preface to his book, The Four Faces of Fourcade, Clare Storrar (1990) wrote: "It is di.cult to appreciate the breadth and depth of Henry Georges Fourcade's intelligence and creative power. He was an intellectual giant, a phenomenon, whose theoretical and practical achievements have never received proper recognition. These were all the more remarkable because he began his original work on photogrammetry when science in South Africa was in its infancy, and he laboured alone far from libraries and other research facilities. His only higher academic training was in land surveying. He was adept in each of four sciences at various stages in his life, but, mainly because of his natural reserve, his reputation was highly compartmentalised. To foresters he was 'the most brilliant forestry officer of his time' to surveyors, he was exceptionally learned in theory and skilled in practice. Photogrammetry was a new subject, unheard of, except by a handful of scientists. In botany, which he took up seriously at the age of fifty-five, his work was highly regarded by leading botanists in South Africa and in Europe. All stood in awe of his extraordinary talent and ability. Some were frightened of him. But few were able—in fact, not even the best brains were wholly qualified—to grasp fully the tremendous intellectual stature and potential of this protean man."
This paper briefly describes the historic achievements of Henry Georges Fourcade, with the emphasis on his land surveying and, in particular, his photogrammetric contributions to science. The centenary of one of these, his proposal of a stereoscopic method of photographic surveying, occurs in October 2001.  相似文献   

6.
 Two numerical techniques are used in recent regional high-frequency geoid computations in Canada: discrete numerical integration and fast Fourier transform. These two techniques have been tested for their numerical accuracy using a synthetic gravity field. The synthetic field was generated by artificially extending the EGM96 spherical harmonic coefficients to degree 2160, which is commensurate with the regular 5 geographical grid used in Canada. This field was used to generate self-consistent sets of synthetic gravity anomalies and synthetic geoid heights with different degree variance spectra, which were used as control on the numerical geoid computation techniques. Both the discrete integration and the fast Fourier transform were applied within a 6 spherical cap centered at each computation point. The effect of the gravity data outside the spherical cap was computed using the spheroidal Molodenskij approach. Comparisons of these geoid solutions with the synthetic geoid heights over western Canada indicate that the high-frequency geoid can be computed with an accuracy of approximately 1 cm using the modified Stokes technique, with discrete numerical integration giving a slightly, though not significantly, better result than fast Fourier transform. Received: 2 November 1999 / Accepted: 11 July 2000  相似文献   

7.
The concept of the Northern Marine Transportation Corridors (NMTC) initiative was developed under the Government of Canada World‐Class Tanker Safety System Initiative (WCTSS). The NMTC is an interdepartmental Arctic initiative within the Department of Fisheries and Oceans Canada (DFO), through the Canadian Coast Guard (CCG) and the Canadian Hydrographic Service (CHS), in collaboration with Transport Canada (TC). The NMTC initiative was developed to strengthen the safety of marine navigation in the Arctic, and to offer an efficient planning guide for present and future Arctic investments. Transportation corridors identified through this initiative will provide the Government of Canada the framework needed to better prioritize and deliver on its programs and services, including: nautical charts and products; aids to navigation; icebreaking services; and marine safety regulations. The corridors were generated and analyzed with a Geographic Information System (GIS) using two main data sources: the Automated Identification System (AIS) and CHS's nautical charts and publications. The geographic extent of the NMTC is defined as the Northern Canada Vessel Traffic Service Zone (NORDREG Zone) and the Mackenzie River. With close to 4 million km2 of water in the Arctic and 162,000 km of coastline, surveying the Arctic to modern standards represents an enormous challenge to CHS. By adopting a corridor‐based approach, CHS and other government programs can prioritize their efforts on 12% of the Canadian Arctic waters. CHS currently has 32% of the NMTC adequately surveyed, with an additional 3% surveyed to modern standards.  相似文献   

8.
《测量评论》2013,45(74):146-155
Abstract

Shortly after the inception of the Geodetic Survey of Canada in 1905, reconnaissance for primary triangulation was commenced in the Ottawa-Montreal area. About the same time, precise levelliilg operations were begun from a bench mark already established by the United States Coast and Geodetic Survey near the International border at Rouses Point in Quebec.  相似文献   

9.
Several hybrid neutral atmosphere delay models have been developed at the University of New Brunswick. In this paper we are presenting UNB3m_pack, a package with subroutines in FORTRAN and corresponding functions in MatLab which provides neutral atmospheric information estimated using the UNB3m model. The main goal of UNB3m is to provide reliable predicted neutral atmosphere delays for users of global navigation satellite systems (GNSS) and other transatmospheric radiometric techniques. Slant neutral atmosphere delays are the main output of the package, however, it can be used to estimate zenith delays, Niell mapping functions values, delay rates, mapping function rates, station pressure, temperature, relative humidity and the mean temperature of water vapor in the atmospheric column. The subroutines work using day of year, latitude, height and elevation angle as input values. The files of the package have a commented section at the beginning, explaining how the subroutines work and what the input and output parameters are. The subroutines are self-contained, i.e., they do not need any auxiliary files. The user has simply to add to his/her software one or more of the available files and call them in the appropriate way. The GPS Tool Box is a column dedicated to highlighting algorithms and source code utilized by GPS engineers and scientists. If you have an interesting program or software package you would like to share with our readers, please pass it along; e-mail it to us at gps-toolbox@ngs.noaa.gov. To comment on any of the source code discussed here, or to download source code, visit our website at . This column is edited by Stephen Hilla, National Geodetic Survey, NOAA, Silver Spring, Maryland, and Mike Craymer, Geodetic Survey Division, Natural Resources Canada, Ottawa, Ontario, Canada.  相似文献   

10.
A consistency test of airborne GPS using multiple monitor stations   总被引:2,自引:1,他引:2  
In October 1990, several airborne GPS tests were conducted in the Ottawa region by the Canada Centre for Surveying (CCS) and the Canada Centre for Remote Sensing (CCRS). Ashtech XII receivers were located at up to three monitor stations with baseline lengths to the aircraft ranging from 1–200 km. Approximately two hours of airborne data, collected at a 2 Hz rate, were available for each of the three test days. Post-processing of the differential data was done using the University of Calgary's SEMIKIN package which utilizes a Kalman filter algorithm to estimate both the remote receiver's position and velocity. Comparisons were made between the aircraft position and velocity determined from each of the monitor stations to assess the consistency of differential GPS when different reference stations are used. Results show that the degree of consistency is dependent upon the distance to the monitor stations. Agreement at the decimetre-level is achieved in position when the baseline lengths are within 100 km. Agreement in velocity is usually better than 1 cm s–1 (RMS).  相似文献   

11.
《测量评论》2013,45(49):116-129
Abstract

The Dominion of Canada, with an area approximating that of Europe, is the largest and most populous of the great self-governing Dominions of the British Empire. Through the British North America Act, 1st July 1867, the Union of Upper and Lower Canada, with Nova Scotia and New Brunswick, were united to form the Dominion, Upper and Lower Canada being designated as the provinces of Ontario and Quebec. An expansion was made possible on 19th November 1869 by the Deed of Surrender to the Crown of the Hudson's Bay Company's territorial, rights in the Northwest. On 12th May 1870 the Province of Manitoba was established, and on 15th July the Northwest Territories were transferred to the Dominion, and Manitoba was admitted into Confederation. Although the boundaries of Manitoba have since been enlarged and those of the Northwest Territories diminished through the creation in 1905 of the Provinces of Saskatchewan and Alberta, the control of the resources and public lands in the West remained under Dominion authority until the year 1930. By this brief statement we are enabled to understand the background of what has developed into the largest connected and systematic Public Lands Survey in any country, that of the Canadian Northwest; and this survey is unique in having been performed under one organization.  相似文献   

12.
Satellite surface soil moisture has become more widely available in the past five years, with several missions designed specifically for soil moisture measurement now available, including the Soil Moisture and Ocean Salinity (SMOS) mission and the Soil Moisture Active/Passive (SMAP) mission. With a wealth of data now available, the challenge is to understand the skill and limitations of the data so they can be used routinely to support monitoring applications and to better understand environmental change. This paper examined two satellite surface soil moisture data sets from the SMOS and Aquarius missions against in situ networks in largely agricultural regions of Canada. The data from both sensors was compared to ground measurements on both an absolute and relative basis. Overall, the root mean squared errors for SMOS were less than 0.10 m3 m−3 at most sites, and less where the in situ soil moisture was measured at multiple sites within the radiometer footprint (sites in Saskatchewan, Manitoba and Ontario). At many sites, SMOS overestimates soil moisture shortly after rainfall events compared to the in situ data; however this was not consistent for each site and each time period. SMOS was found to underestimate drying events compared to the in situ data, however this observation was not consistent from site to site. The Aquarius soil moisture data showed higher root mean squared errors in areas where there were more frequent wetting and drying cycles. Overall, both data sets, and SMOS in particular, showed a stable and consistent pattern of capturing surface soil moisture over time.  相似文献   

13.
14.
A recursive least squares algorithm is presented for short baseline GPS positioning using both carrier phase and code measurements. We take advantage of the structure of the problem to make the algorithm computationally efficient and use orthogonal transformations to ensure that the algorithm is numerically reliable. Details are given for computing position estimates and error covariance matrices with possible satellite rising and setting. Real data test results suggest our algorithm is effective.This research was supported by NSERC of Canada Grant RGPIN217191–99, FCAR of Quebec Grant 2001-NC-66487, and NSERCGEOIDE Network Project ENV#14 for Xiao-Wen Chang, and by NSERC of Canada Grant RGPIN9236–01 for Christopher C. Paige.An erratum to this article can be found at  相似文献   

15.
The use of a 35 mm or similar camera set up over a theodolite is described for surveying mountain and polar glaciers where conditions do not allow for extensive detailed surveying or the use of heavy phototheodolites. Though used initially by Spender and Wright in the 1930s on Mount Everest and in Greenland and Arctic Canada, but apparently not by others since then, it was again tried out by Wright in Iceland in 1992. Modern analytical techniques have shown that heights accurate to within 2 m can be obtained from these photographs at distances up to 5 km. In addition, five times as many points can be identified and intersected in the laboratory from the photographs as was possible using sketches in difficult field conditions. Some reasons are suggested for the lack of use of this technique by others. The potential of existing survey photographs taken in Arctic Canada for large scale surveys of high polar glaciers in 1938 is described, with the hope that glaciologists and photogrammetrists might undertake their analysis.  相似文献   

16.
A recursive least squares algorithm is presented for short baseline GPS positioning using both carrier phase and code measurements. We take advantage of the structure of the problem to make the algorithm computationally efficient and use orthogonal transformations to ensure that the algorithm is numerically reliable. Details are given for computing position estimates and error covariance matrices with possible satellite rising and setting. Real data test results suggest our algorithm is effective.This research was supported by NSERC of Canada Grant RGPIN217191–99, FCAR of Quebec Grant 2001-NC-66487, and NSERCGEOIDE Network Project ENV#14 for Xiao-Wen Chang, and by NSERC of Canada Grant RGPIN9236–01 for Christopher C. Paige.The online version of the original article can be found at  相似文献   

17.
1593年刻印的《乾坤万国全图天下人物事迹》地图载有亚伯尔耕、加拿大的名字,没有亚墨利加,显示明代知道新大陆的地名比利玛窦制作的《坤舆万国全图》早9年。1570年的奥特里斯的世界地图说明欧洲还没有到过美洲西部。普兰修斯1590年和1594年的地图完善了欧洲人还没有到过美洲的西部和亚洲地理,比对中文的《坤舆万国全图》的准确性,唯一可能是西方采纳了来自中国的信息。其中最大可能是荷兰航海者林斯豪滕和他相熟的中国通在印度果阿的交流,果阿是郑和当年必经之地。1590年后,西方地图有了飞跃的发展,其后西方海洋霸权中心从葡萄牙转移到荷兰和英国。奥特里斯1570年的世界地图,普兰修斯1590年与1594年的世界地图,3种地图逐步改善了西方对新大陆和中国的认识,但是没有欧洲人测量的文献根据,应该是中国的世界地理知识传入西方。《乾坤万国全图天下人物事迹》《郑和航海图》与《坤舆万国全图》代表3种不同用途的地图,均为中国创绘。《坤舆万国全图》的原图是明代内府藏的世界地图,约1430年成图,远早于利玛窦和李之藻时代。明代中国人是世界地理大发现者,是现代地图学的先驱,地图学起码是中国独立创建的,不是来自西方。  相似文献   

18.
PREFACE There are various publications on the 90th birthday of Gottfried Konecny.His involvement in the International Society for Photogrammetry and Remote Sensing(ISPRS)is particularly described by others.Here,his forward-oriented impulses in research and development at the former Institute for Photogrammetry and Engineering Survey of the(Technical)University of Hannover,today Institute for Photogrammetry and Geoinformation,Leibniz University Hannover,and some of his activities supporting developing and other countries by given short-term courses are highlighted.Gottfried Konecny was always one of the first in pushing new technologies.With the analytical plotter AP/C-3,he introduced analytical photogrammetry in Germany.Based on his experience with this not really operational version,he induced the company Zeiss to develop the first really operational analytical plotter Planicomp,which resulted in the end of analog photogrammetric devices and their limitations.At the invitation of Gilbert Hobrough,a mainly hardware-based image correlator was developed for the AP/C-3 in Hannover which anticipated many of today's applications.Gottfried Konecny initiated remote sensing in Germany.Based on his proposal with the Metric Camera Flight on Spacelab,the then highest resolution civil stereoscopic space images available were generated.Despite limited computer performance at his institute,a digital stereo plotter was developed,using hardware components from the cooperating Swedish company Context Vision,long before digital stereo workstations with increased and affordable computer capacity were possible.Also,in the area of GIS,he too,pushed development in collaboration with companies and administrations.Shortly before the end of his time as head of the institute,and more so after he became emeritus professor,he started a series of educational workshops,particularly in developing countries,but also other countries,to support the development of photogram-metry,remote sensing and GIS.He promoted the use of space imagery for mapping to improve the situation of poorly updated topographic maps.  相似文献   

19.
Wavelet evaluation of the Stokes and Vening Meinesz integrals   总被引:1,自引:0,他引:1  
The wavelet transform is a powerful tool in evaluating some singular geodetic integrals. Due to its localization properties in both the time (space) and frequency (scale) domains, and because the kernels of some geodetic integrals have singular points and decay smoothly and quickly away from the singularities, many wavelet transform coefficients of the kernels become zeros or negligible, and only a small number of wavelet transform coefficients are significant. It is thus possible to significantly compress the kernels of these integrals on a wavelet basis by neglecting the zero coefficients and the small coefficients below a certain threshold. Therefore, wavelets provide a convenient way of efficiently evaluating these integrals in terms of fast computation and savings of computer memory. A modified algorithm for the wavelet evaluation of Stokes' integral is presented. The same modified algorithm is applied to the evaluation of the Vening Meinesz integral, whose kernel has a stronger singularity than does Stokes' kernel. Numerical examples illustrate the efficiency and accuracy of the wavelet methods.Acknowledgments.The author express their sincere thanks to Dr. Salamonwicz for providing his PhD thesis. E-mail correspondence between the authors and Dr. Barthelmes and Dr. Benciolini contributed to the work. R. Benciolini and the other two anonymous reviewers are thanked for their constructive comments. Support for this research was provided by research grants to Dr. Sideris from the Natural Sciences and Engineering Reserch Council of Canada (NSERC) and the Geomatics for Informed Decisions (GEOIDE) Network of Centres of Excellence. The MATLAB Wavelet Toolbox package was used as the platform to develop the software in this project.  相似文献   

20.
The North American datum of 1983: Project methodology and execution   总被引:1,自引:0,他引:1  
A new adjustment of the geodetic control networks in North America has been completed, resulting in a new continental datum—the North American Datum of 1983 (NAD 83). The establishment ofNAD 83 was the result of an international project involving the National Geodetic Survey of the United States, the Geodetic Survey of Canada, and the Danish Geodetic Institute (responsible for surveying in Greenland). The geodetic data in Mexico and Central America were collected by the Inter American Geodetic Survey and validated by the Defense Mapping Agency Hydrographic/Topographic Center. The fundamental task ofNAD 83 was a simultaneous least squares adjustment involving 266,436 stations in the United States, Canada, Mexico, and Central America. The networks in Greenland, Hawaii, and the Caribbean islands were connected to the datum through Doppler satellite and Very Long Baseline Interferometry (VLBI) observations. The computations were performed with respect to the ellipsoid of the Geodetic Reference System of 1980. The ellipsoid is positioned in such a way as to be geocentric, and its axes are oriented by the Bureau International de l'Heure Terrestrial System of 1984. The mathematical model for theNAD readjustment was the height-controlled three-dimensional system. The least squares adjustment involved 1,785,772 observations and 928,735 unknowns. The formation and solution of the normal equations were carried out according to the Helmert block method. [Authors' note:This article is a condensation of the final report of the NAD 83 project. The full report (Schwarz,1989) contains a more complete discussion of all the topics.]  相似文献   

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