bluuebunny/crossref_metadata_2025 huggingface dataset:
Abundant genetic diversity and maternal origins of modern horses
Authors: Lu Hongzhao , Bai Hao , Wang Ling , Zhang Tao
Published: July 2019

To clarify the origin and genetic diversity of modern horses, mitochondrial DNA (mtDNA) D-loop sequences were generated for 3965 horses from 12 geographical regions. From these sequences, we observed 439 haplotypes defined by 138 polymorphic nucleotide sites. All horses were genetically diverse (HD = 0.973 ± 0.001, π = 0.0243 ± 0.0005), which showed that maternal lineages of the domestic horse are worldwide highly diverse. In general, all 18 haplogroups were presented in the Asian horse. The majority of modern horse sequences belong to haplogroups L, Q, and A. At the same time, 194 archaeological samples from four geographical regions were obtained. Indeed, haplogroup distributions are overlapping in modern and ancient samples, indicating that most haplogroups were already present in ancient times at least in Europe and Asia. The network showed that breeds of Asian and Europe regions overlapped, suggesting that extensive gene flow had occurred between different horse breeds in Asian and European regions.
Genome-wide identification and expression analysis of the PTP family in Chinese cabbage (Brassica rapa subsp. pekinensis)
Authors: Liu Mingfeng , Ren Jie , Ye Xueling , Jiang Xin , Li Qingqing , Wang Lin , Liu Zhiyong
Published: July 2019

Protein tyrosine phosphatases (PTPs) are signaling enzymes that play an important role in plant growth and development. Bioinformatics was used to analyze the PTP gene family of Brassica rapa subsp. pekinensis. Forty-six BrPTP family members were identified. These families were divided into eight subfamilies according to the protein domain. The relationship between gene structure and evolution was determined by comparing gene structure with the evolutionary tree. The 46 BrPTP genes were unevenly distributed across the chromosomes, and two pairs were identified to be tandem repeats. The BrPTP domain contained eight important motifs. Motifs of the same subfamily were basically identical, whereas that of each subfamily differed. These common motifs in these subfamilies are essential for PTP protein function. Analysis of BrPTP by quantitative reverse-transcription PCR revealed tissue-specific differences in expression. Most of the BrPTP genes were expressed in the five tissues examined, but not all. Expression patterns under stress showed that most genes were involved in the stress response. Further study of the PTP gene family may reveal more of its functions in Chinese cabbage.
Offshore legal surveys — datums and charts
Authors: Jones Harold E. , Gray David H.
Published: July 2019

This review paper describes the role of the legal surveyor in the offshore and his increasing concern for survey accuracy and reliability. It sets out the interrelationships between legal and hydrographic surveys and their common concerns with datums.

In the 1970s, offshore survey regulations under the Canada Lands Surveys Act defined the Grid Area boundaries based on approved North American Datum of 1927 (NAD27) coordinates of the original well. However, with satellite survey techniques and NAD83, it is possible to define the limit in terms of the Datum. Thus, there has been a shift of emphasis from monumentation to survey accuracy and reliability.

Jurisdictional boundaries are often related to low water line on nautical charts. Such boundaries are dependent on the horizontal datum of the charts. Thus, it is important that charts be revised to NAD83 so that boundaries defined from them can be expressed in terms of NAD83 and shown on legal survey plans.
Nouveaux progrès dans le développement d’une station gyroscopique automatique
Authors: Jeudy L.M.A. , Jobin J. , Fournier D.
Published: July 2019

A description and tests of a North seeking automated gyroscopic station developed at the Metrology Laboratory of the Geodetic Sciences and Remote Sensing Department of Laval University are presented. The station is based on a Wild GAK-1 suspended gyrocompass. Automatization is realized by using an optoelectronic eyepiece replacing the original eyepiece. 512 CCD (Charged Coupled Device) photodiodes sense the gyroscope instantaneous positions 30 times per second for exactly one period (about 7 minutes). The equilibrium position is computed from these 12600 positions (12600=30x7x60). The calculation is made in real time. It is based on numerical integration and on a special filtering technique using moving averages. A correction for damping is applied. Azimuth is finally obtained after multiplication by and addition of calibrating constants. The above cycle is repeated every 10 minutes. A dedicated microcomputer stores the azimuths and computes a cumulated final azimuth at the end of each cycle. Such azimuth determinations show an accuracy of five arcseconds (5") after fifty minutes (50mn) of automated operation. A longer time of operation does not improve precision.
Calibration baselines in canada
Authors: Gillis D. , Nabe L.
Published: July 2019

The establishing, measuring and monitoring of Electronic Distance Measurement (EDM) cali¬bration baselines in Canada is a joint program of the Geodetic Survey of Canada and provincial, territorial and municipal surveying agencies. Since its establishment in 1971, the 2.3 km National Geodetic Baseline (NGBL) in Ottawa has been used as the reference baseline for other calibration baselines; two precise EDM instruments, the Mekometer ME3000 and the Geomensor CR204, have been used to transfer the length standard of the NGBL to baselines across Cana¬da. Thirty-six calibration baselines, established as part of the National Baseline Program, now exist. The Geodetic Survey strives to maintain the published values of interpier distances at the highest accuracy possible. To this end, extensive remeasurements are being planned. For longer distances which may be required to calibrate or check GPS instruments, a calibration network with lines up to 222 km is being established.
The real property report the early aftermath
Authors: Allred G.K. , Loeppky S.M. , Mattson N.R.
Published: July 2019

On September 1,1987, the Alberta Land Surveyors’ Association implemented a codified standard for the certification of building locations relative to property boundaries, i.e., building location certificates. Despite considerable discussion on the subject between members of the surveying profession and mortgage lenders, development officers and lawyers over the last several years, the implementation of this standard received instant attention from all participants in real estate transactions.

The reaction to the implementation of this standard for real estate surveys varied from outright hos¬tility on the part of some purchasers, who view the requirement for a surveyors’ certificate as an unneces¬sary and extra cost imposed by mortgage companies, to total acceptance of the standard as a bare mini¬mum by most solicitors, who fully comprehend the problems where the paper title does not agree with the physical attributes of the property on the ground.

Meetings were held with various interested groups to discuss the requirements of the Real Property Report with regard to determination of “marketability of title” and in particular “extent of title.”
Road network extraction from spot panchromatic data
Authors: O’Brien Douglas
Published: July 2019

The efficient revision of cartographic data bases using digital imagery implies some form of feature extraction. At present classification techniques can be used to extract certain area outlines, but the automatic detection of linear features such as roads is difficult. One possible method of extracting these features is through mathematical morphology.

Mathematical morphology is a form of image treatment that has been applied to remote sensing in recent years. It is possible to extract a binary representation of the road network in an image using this approach, and then treat the results to remove extraneous features.

The results demonstrate this process extracts, to a large extent, the information desired. Several caveats must be considered before viewing this as a practical solution. These include processing time, areas where it can be applied, and content of the results.
Information content of spot data for topographic mapping of the sherbrooke, quebec, test area
Authors: Thirlwall Stephen L.
Published: July 2019

SPOT HRV images were evaluated for their content of thematic information in relation to specific geographical features required for 1:50 000 scale topographic maps. Information was extracted by visual methods from multispectral and panchromatic image transparencies using the PROCOM-2 system.

Mapping experiments were carried out on the Sherbrooke, Quebec, test area by experienced interpreters who had limited background knowledge of the area.

Excellent feature detection and identification were achieved with SPOT images, especially for linear cultural features (e.g., road, railway). Limitations to mapping related mostly to very small area or point form features (e.g., building, tower, junkyard). Results improve when both multispectral and panchromatic images are used for interpretation. BULK corrected images are very suitable for quick and accurate visual mapping. Stereo-analysis is not essential, but provides a good supplement to mapping.

We conclude that SPOT images have a most encouraging potential for topographic mapping, particularly if supported by appropriate field verification.
Investigations of spot cartographic applications in the u.s. geological survey
Authors: Thormodsgard J.M. , Kelly G.G. , Spooner J.D.
Published: July 2019

The U.S. Geological Survey has a longstanding commitment to the advancement of the technology and applications of remotely sensed data from civilian satellite systems. In the past, research based on satellite data was primarily directed toward natural resource and land use applications rather than cartographic applications.

The availability of high-resolution, stereoscopic data from the sensors on the Système Probatoire d’Observation de la Terre (SPOT) satellite platform provides new opportunities for cartographic applications. The potential applications include production of satellite image and topographic maps, and generation of digital elevation data. Investigations into these applications of SPOT data were recently initiated by the U.S. Geological Survey.
Integration of the global positioning system with geodetic leveling surveys in ground subsidence studies
Authors: Chrzanowski Adam , Yong-qi Chen , Leeman Roger W. , Leal Julio , Maraven
Published: July 2019

Integration of GPS measurements with terrestrial geodetic leveling has been implemented by the authors in monitoring ground subsidence in oil fields in Venezuela in an area of about 50 km x 50 km. The subsidence rate reaches up to 20 cm/year. A mathematical model for combining the GPS surveys with dynamic leveling measurements has been developed by utilizing the well known University of New Brunswick generalized method of deformation analysis. The implementation of GPS was preceded by test surveys (5 survey campaigns) in Canada on a network with 0.7 km to 30 km baselines, using TI 4100, WM101, and Trimble 4000SX receivers, and on a portion of the monitoring network in Venezuela (2 survey campaigns) using WM101 receivers. The accuracy of the test surveys has been evaluated using MINQE technique and by comparing the subsidences determined with GPS and precise leveling. The results indicate that with C/A-code receivers and with the present geometry of the satellite distribution, the vertical component of the short and medium (up to 30 km) length of the GPS baselines can be determined with an accuracy ranging from 15 mm in a moderate climate to 30 mm in hot and humid conditions.
The role of the geoid in one-, two-, and three-dimensional network adjustments
Authors: Sideris Michael G.
Published: July 2019

The geoid and its horizontal derivatives, the deflections of the vertical, play an important role in the adjustment of geodetic networks. In the one-dimensional (1D) case, represented typically by networks of orthometric heights, the geoid provides the reference surface for the measurements. In the two-dimensional (2D) adjustment of horizontal control networks, the geoidal undulations N and deflections of the vertical ξ, η are needed for the reduction of the measured quantities onto the reference ellipsoid. In the three-dimensional (3D) adjustment, N and ξ, η are basically required to relate geodetic and astronomic quantities. The paper presents the major gravimetric methods currently used for predicting ξ, η and N, and briefly intercompares them in terms of accuracy, efficiency, and data required. The effects of N, ξ, η on various quantities used in the ID, 2D, and 3D network adjustments are described explicitly for each case and formulas are given for the errors introduced by either neglecting or using erroneous N, ξ, η in the computational procedures.
The use of strapdown technology in surveying
Authors: Schwarz K.P. , Knickmeyer E.H. , Martell H.
Published: July 2019

Inertial technology has been successfully used in surveying and geodesy for more than a decade. Although results in positioning and gravity vector determination have been excellent, the high cost of the stable platform systems, their bulkiness and their susceptibility to down times in a rough production environment, have somewhat limited the use of this new technology. In addition, a number of interesting applications could not be attempted because raw accelerations and angular velocities at a high data rate were not available. The Department of Surveying Engineering at the University of Calgary has therefore studied the use of strapdown technology for surveying applications and the paper summarizes results achieved during the last two years. They show that strapdown technology offers an economic, versatile and reliable way to solve surveying problems in a number of areas where platform systems could not be used or were not competitive. Four developments will be specifically highlighted. The testing of a Strap-down Inertial Survey System (SISS), the development of an inertial pipeline monitoring system, the testing of an integrated INS/GPS for airborne photogrammetry and line imaging, and studies leading to the development of an inertial system for industrial alignment surveys. In each case, the concept of the specific application will be outlined and a brief discussion of the results achieved to date will be given.
Assessment of observations using minimum norm quadratic unbiased estimation (minque)
Authors: Chen* Y.Q. , Chrzanowski Adam , Kavouras M.
Published: July 2019

Estimation of the variances and covariances of observations in geodetic and engineering surveys of high precision is of great importance for proper weighting of the observations in their subsequent processing and for better understanding of sources of errors and their modeling. The authors have adopted from modern statistics the Minimum Norm Quadratic Unbiased Estimation (MINQUE) method for the variance-covariance component estimation. The method has successfully been implemented in modeling the error propagation in geodetic leveling, in determination of error components and weighting of measurements with the Global Positioning System, and in an assessment of a triangulateration network observed with different EDM instruments.
Planning gps surveys - using appropriate precision indicators
Authors: Merminod1 B. , Grant2 D.B. , Rizos C.
Published: July 2019

In the planning of a GPS survey, one of the basic tasks is to answer these questions:

Which satellites should I observe? How long should I observe for? What time of day should I schedule observations?

To answer such questions it is necessary to have an objective measure of the precision attainable for position determination by GPS techniques. At present, the indicators of precision commonly available are based on notions of relative satellite geometry as borrowed from GPS navigation principles, and are only of limited use in GPS surveying. In particular, for short baselines, the reliable resolution of the carrier cycle ambiguities during the phase reduction stage is the key to precise relative GPS surveying. The authors have developed a number of precision indicators for GPS surveying which could be used to maximise the probability of resolving ambiguities. The computation of these proposed indicators will assist in satellite selection and estimating the appropriate observation session times and length for GPS surveying. The utility of these indicators has been supported by studies that have shown that not only is the internal precision of the coordinate results maximised, but the sensitivity to systematic errors is also to a large extent reduced. Strategies for the use of these indicators are suggested.
Designing a property fabric information system for canada lands
Authors: Campbell Gord , Egesborg Paul
Published: July 2019

The efficient access to and management of approximately 100 000 cadastral survey related records by the Federal Department of Energy, Mines and Resources, Legal Surveys Division, requires the application of GIS and Data Base Management technology. This paper discusses the design process, general specifications, functional requirements, and data model, of a Property Fabric Information System now in development in the Division. This system will be the GIS component of an Automated Canada Lands Information System that the Division will use to manage the majority of its administrative and technical data. The data conversion methodology that will be used to build the databases for this cadastral GIS application, is also outlined.
Problems with handling spatial data — the voronoi approach
Authors: Gold Christopher M.
Published: July 2019

Experience with the handling of spatial data on a computer led to the identification of a variety of “awkward” problems, including interpolation, error estimation and dynamic polygon building and editing. Many of the problems encountered could be classified as “spatial adjacency” issues. The Voronoi diagram of points and line segments in the Euclidean plane is shown to give a functional definition of spatial adjacency. The basic operations for incremental construction and maintenance of this Voronoi diagram and its dual are described, and a variety of applications are outlined.
Education and training in geomatics in canada
Authors: Groot Richard
Published: July 2019

Education and training in Geomatics must be demand-driven activities.

This paper examines the impact of computer and communications technology on government institutions and private-sector organizations involved in Geomatics as the background for changing and new jobs requiring specific education and training. This new demand needs to be matched to an effective response from education institutions. To assist in making this match the paper proposes a model describing the functions and jobs with their linkages in these organizations, and it proposes an education/training model for Geomatics.

The paper identifies a major need for ongoing Geomatics education for people now in the surveying and mapping workforce and suggests how this activity can be coordinated to make best use of scarce professional and facility resources in Canada.

Finally, the paper emphasizes the need to address, in academic curricula, explicitly and deliberately the institutional and management issues involved in implementing spatial information technology into existing organizations.
Extending freedom of information and privacy legislation to municipalities in ontario
Authors: Wilkinson Margaret Ann
Published: July 2019

In 1991, a new statute, the Municipal Freedom of Information and Protection of Privacy Act, 1989, came into effect in Ontario. It is modeled on the earlier Freedom of Information and Protection of Privacy Act, 1987 which continues to apply to public sector organizations at the provincial level. Rather than provide an overview of this area of legislation, this article concentrates on certain aspects of the legislation which may prove to be troublesome to members of the public using these statutes in the future. These potential difficulties in some cases lie in differences between this new statute which governs the conduct of municipal bodies and the original statute which applies to provincial organizations. Other problematic areas are common to both statutes.
ATMOSPHERIC REFRACTION AND TEMPERATURE GRADIENT
Authors: Angus-Leppan P.V.
Published: July 2019

The coefficient of refraction is far from constant. It varies chiefly because of changes in the vertical temperature gradient of the atmosphere. From measurements of vertical angles between points of known heights, observed angles of refraction can be deduced. By the use of simultaneous meteorological measurements, various methods of calculating refraction are developed. It is necessary to derive a formula representing temperature as a function of height and time of day. Calculated refraction compares accurately with observed, especially when solar radiation intensity measurements are used.
THE BRITISH COLUMBIA AIR PHOTO LIBRARY
Authors: Kinnear A. C.
Published: July 2019

Scientific bodies of the eighteenth and nineteenth centuries set up standards of length related to natural quantities such as the length of the seconds pendulum or of a meridional arc. Finding the determinations of these natural quantities to be inaccurate, they later redefined the standards by reference to fine ridings on metal bars. But these bars were found to undergo small secular changes, and scientists of the twentieth century have returned to natural quantities and have now (1960) defined a standard of length by reference to a wavelength of light that is believed to be constant and to be measurable in national laboratories.
RELIEF PORTRAYAL ON LOW-LEVEL PILOTAGE CHARTS
Authors: Laidlaw G. A.
Published: July 2019

One of the features of the Low-Level Pilotage Chart at the scale of 1:500,000 is the combination of shaded relief with contours and hypsometric tints. The purpose of the shading is to create a three-dimensional effect that will make relief features easily recognizable by the pilot. This paper describes the techniques used in production of the shaded relief at the Surveys and Mapping Branch of the Department of Mines and Technical Surveys.
REDUCTION OF ELECTRONIC LENGTH MEASUREMENTS
Authors: Saastamoinen J.
Published: July 2019

The following is a review of the method of correcting electronic length measurements for slope, height above sea level, and curvature of electric waves.
THE USE OF POLYNOMIALS IN THE THREE-DIMENSIONAL ADJUSTMENT OF TRIANGULATED STRIPS
Authors: Schut G. H.
Published: July 2019

The treatment of this subject in recent publications is discussed. The procedure described by M. Perks in the present issue of THE CANADIAN SURVEYOR is found to be the most accurate, but it is more complicated than it need be.

The procedure adopted at the National Research Council of Canada is then described. This makes use of a sequence of conformal transformations in two dimensions. It has the same accuracy as Perks’s procedure, but it is simpler in both formulation and use.
PROBLEMS IN CARTOGRAPHIC NOMENCLATURE
Authors: Delaney G. F.
Published: July 2019

The paper discusses the desirability of a more serious and systematic approach to map nomenclature on the part of cartographers. It points out that while local usage would seem to provide a ready-made list of names for some areas, overlapping or other problems usually lessen the value of local usage—Finally, the author gives a number of illustrations of the difficulties in map nomenclature caused by the existence of several languages in an area.
COMPUTER AND PROGRAMS FOR THE AP-C ANALYTICAL STEREOPLOTTER
Authors: Johnson E. C. , Kamm V. C.
Published: July 2019

Tbe AP/C control computer is a specially designed, high speed, serial, binary, general-purpose machine with approximately 2000 words of memory. Although the machine is basically a general-purpose computer, in includes special facilities for communicating with the operator of the AP/C Stereoplotter for inputs from the operator’s handwheels and footwheel, and for outputs to servomechanisms on the AP/C viewing unit and coordinatograph. A complete set of programs for inner, relative and absolute orientations and for plotting operations is provided. In addition, the computer may be used for general-purpose computing when not required for plotting. In speed and versatility it is superior to most medium-size commercial computers.
N. R. C. MONOCOMPARATOR
Authors: Smialowski A. J.
Published: July 2019

In view of the increasing importance of monocular measurements and the corresponding demand for a precise monocular comparator, an instrument with the novel idea of a multiple measuring mark was originated at the National Research Council of Canada.

The characteristic features of this instrument, called the N.R.C. Monocomparator, based on the multiple measuring mark system, are: built-in precision and dimensional stability, fast slewing motion, and very simple optical system.
PHOTOGRAMMETRY IN THE VINELAND LEGAL SURVEY
Authors: Brocklebank R. A.
Published: July 2019

This paper describes the aerial photography, photogrammetric procedures, computations and adjustments, and analysis of results of the experimental legal survey of the Vineland area. It was found that mean-square positional accuracy of the order of 10 microns could be achieved, and it was concluded that relatively high accuracy could be realized by photogrammetric methods in determining positions of pre-selected and targeted points such as property corners. Other facts emerging from the experiment indicate that research into the use of photogrammetry in legal surveying should be continued.
USE OF PHOTOGRAMMETRY ON A LEGAL RETRACEMENT SURVEY
Authors: Krebs H.
Published: July 2019

In 1961 and 1962 the Office of the Director of Titles of the Province of Ontario, in collaboration with Hunting Survey Corporation Limited, carried out a legal retracement survey by a combination of photogrammetry and ground survey methods as an experiment in the use of photogrammetry in legal surveying, the Director of Titles conducting the ground survey and Hunting doing the photography and photogrammetry. This paper describes the ground surveys and the comparisons of results, and concludes that a retracement survey covering a larger area than the one used in the test and being otherwise similar could utilize photogrammetry to considerable advantage.
A METHOD EMPLOYED BY THE CANADIAN ARMY FOR MAPPING ARCTIC AREAS WITH ELECTRONIC COMPUTER ASSISTANCE
Authors: O’Brien L. J.
Published: July 2019

Described in this article is a method employed by the Canadian Army for extension of horizontal control by computer-assisted photogrammetry. In particular, a description is given of the application of this method to the 1:250,000 scale mapping of Cornwallis Island located in the Arctic Archipelago and having an area of about 3,000 square miles. Initial data for the mapping consisted of position values for 18 ground survey points located around the perimeter of the island, airborne profile recordings covering the island at 9-mile intervals and air photography at 1:60,000 scale. Photogrammetric control was extended into each photo overlap by aerotriangulation in a Multiplex plotter concurrent with the plotting of topographic detail. Errors in the photogrammetric control coordinates were reduced to a minimum by an iterative transformation procedure employing an electronic computer. The topographic detail was then scaled to the adjusted control by photographic means.
THE FIRST LINE IN THE CARTOGRAPHY OF CANADA
Authors: Layng Theo E.
Published: July 2019

The true pattern of the discovery of Canada is still a matter of controversy. Who followed the Norsemen — the Portuguese or the English? From what direction was the approach made to Canadian waters — northeast, east, or southeast?

Against this uncertain background three of the earliest surviving maps to show any part of Canada are presented. Which one of them is most likely to have been drawn from the first primary sketches to be made of our coasts? The further question is involved whether the first line to be laid down on the map of Canada was on an east-west axis, or whether it trended north and south. When this question is solved there still remains the small matter of identifying the coasts of these maps with their modern counterparts.
SATELLITE PHOTOGRAPHY
Authors: Taggart C. I.
Published: July 2019

The first real-time satellite photography of the earth was taken on April 1, 1960, when TIROS I, an experimental meteorological satellite, was launched from Cape Canaveral and took photos of the Gulf of St. Lawrence on its first orbit. This paper describes the satellite and its TV camera, discusses the combined U.S.-Canadian research project TIREC associated with it, and lists some of the uses of the satellite photographs that have been obtained — ice reconnaissance; cloud identification and heighting; spotting forest fires; applications to water resources, flood control, and conservation programs; prediction of locust swarms; and satellite photogrammetry for meteorological uses. The paper concludes with a description of the APT (automatic transmission system) used in TIROS VIII to give the first direct reception of a space picture in Canada.
AN INTEGRATED SURVEY SYSTEM FOR BRITISH COLUMBIA
Authors: Andrews G. S.
Published: July 2019

This paper, organized in the manner of a survey traverse, outlines a program for integration of surveys in British Columbia that includes the following principles: step-by-step approach, taking advantage of any existing favourable factors; concentration of effort on essential work only; adequacy of control, both as to quality and to monumentation; flexibility of specifications, allowing for up-grading of accuracy and revision of coordinates; promotion of secondary points to primary control status; and compulsive legislation. Responsibility for the program would be shared by all levels of government, and by industry, business, and individual owners. The paper describes proposed legislation in British Columbia to give effect to survey integration; gives details of field preparation on the provincial level in two areas where integration is now in progress; cites one example of survey integration already existing; and lists some of the benefits to be expected from integration of surveys.
AN APPLICATION OF THE PRINCIPLES OF EXPERIMENTAL DESIGN
Authors: Vlcek J.
Published: July 2019

Some elementary principles of experimental design and analyses are presented. An example of an experiment in photogrammetry is included to illustrate the principles discussed.
Classical Concepts of Least Squares Adjustment
Authors: Konecny Gottfried
Published: July 2019

A review of the fundamental classical concepts of least squares adjustment, based on the development by Gauss is presented. The method of least squares leads to a most probable value of the adjusted quantity under the assumption that the arithmetic mean yields the most probable result and that the uncorrelated observations are normally distributed. It is shown further that the method of least squares leads to an adjusted value with a resulting smallest standard error for any symmetrical distribution. It is indicated that this is also true for correlated observations and that various statistical tests make least squares adjustment a powerful tool for statistical analysis.
Estimation of the Form of the Best Fitting Model
Authors: Vlcek J.
Published: July 2019

Fitting of linear models occupies a large portion of the adjustments of surveying data. In this paper, an attempt is made to present the main ideas of the statistical theory connected with the estimation of linear models, based on the method of least squares. A method of solution of normal equations is given, which lends itself to a simple geometric interpretation and has particular statistical advantages. Also, some possibilities for testing the adequacy of the fitted model are discussed.
The Subtense Bar — Its Use and Its Errors
Authors: Babbage G.
Published: July 2019

This article is intended primarily for the cadastral surveyor or engineer who knows little about the subtense bar but would like to know more. It describes briefly the device and the basic measuring procedure, discusses significant errors inherent in subtense measurement, and concludes with some suggested uses for the bar. Those errors involving the transit have been treated at some length — in fact, they form the gist of what follows — mainly because they are apposite to all semi-precise small angle determinations and may help observers to get the best from their second-reading theodolites.

In this electronic distance-measuring age, it may seem strange to some that a device as basically simple as the bar should warrant study. This attention is worth-while, however, because it allows accurate and rapid determination of short distances under certain conditions. Furthermore, at about $350, it is relatively cheap. Finally, it does not require two 50-pound batteries or a portable generator as inseparable companions.
Design and Application of Automatic Levels
Authors: Schellens Dieter F.
Published: July 2019

In this article, the author outlines the construction of automatic levels and assesses the accuracy of the various types of instruments. The ease of operation and the rapidity with which readings can be taken are pointed out. The author closes with a strong recommendation for the use of such levels in both geodetic and engineering surveying.
Compilation and Separation — A New Approach
Authors: O’Brien L. J.
Published: July 2019

This article describes a method used by the Canadian Army Survey Establishment for color-separating map detail at the manuscript compilation stage. A manuscript, consists of a control plot and a number of sheets of scribe-coat material, one for each color. Stereoplotting is carried out at two positions simultaneously, at the platen in front of the operator and under the pantograph. The scribe-coat material, situated on the pantograph table, is changed between the plotting of each color category of detail. Correct registration of the various categories is ensured by keying the scribe-coat sheets on studs and by the actual build up of detail as a single entity at the platen. The result of the plotting phase is a set of color plates in pencil that can be scribed immediately. Time is saved by the elimination of “touch-up” recopying by the plotter operator and by the reduction of camera processing required.
The Refractive Index in the Reduction of Tellurometer Data
Authors: Bretterbauer Kurt
Published: July 2019

Assuming that the difference in elevation between two points is known, the author develops a formula that will give, in his opinion, the most plausible value for the refractive index for the reduction of tellurometer distance between these points. The meteorological data, measured at both points, are also used in this development.
The Determination of Tree Heights from Parallax Measurements
Authors: Schut G. H. , Wijk M. C. Van
Published: July 2019

This paper discusses the various formulas in use for the computation of tree heights from parallax measurements in aerial photographs. The errors in the computed tree heights, caused by the various error sources, are derived for three different cameras and four flying heights. The results of experiments are given and conclusions are drawn on the choice of formula and camera format and the accuracy that can be obtained in practice.
Calibration of Measuring Devices
Authors: Henriksen Soren
Published: July 2019

The principles for calibrating measuring devices by using a calibrated grid and for calibrating a grid by using a calibrated device are well known. It is not as well known that both device and grid can be calibrated simultaneously (to within a scale factor) to any desired degree of accuracy. It is shown that such calibration is possible and the theory and procedure for doing it are given.
The Role of the Aerial Survey Industry in the Economy of Canada
Authors: Rowlands T. E.
Published: July 2019

Developments directly related to military activity during World War II have led to the formation of a Canadian aerial survey industry. Precise instruments for measuring the surface of the land and for probing beneath the surface are today being used to assess the natural wealth of the country. Although the industry is modest in size, it has a massive impact upon the economy and touches upon almost every aspect of the country’s development.
The Town of Hawkesbury Survey
Authors: Wildman W. N. , Bellach G.
Published: July 2019

This article concerns a survey required by a community where little, if any, original monumentation was placed and where much of the occupational evidence disagreed with plan dimensions. It outlines possible remedies, describes the action taken to effect a remedy, comments on the survey and concludes with the cost and the result.
An Interpolation Method for Strip Adjustment
Authors: Somogyi* J.
Published: July 2019

This paper describes a method of strip adjustment by means of linear three-dimensional transformations applied to the individual models. The first and the last model are transformed independently, using at least three ground-control points. The intermediate models are transformed in a manner that minimizes the jumps in scale, azimuth and tilt, and enforces the fit at intermediate ground-control points. Coordinate connections are made at the centers of gravity of the carryover points. The results of the adjustment of two short strips of 11 and 12 models are shown.
Statistical Properties of Least Squares Estimates
Authors: Sunter A. B.
Published: July 2019

The purpose of this paper is to show that the validity of the method of least squares does not depend on the normality of the observations and that the method gives estimates which are ‘best’ among a broad class of estimates. A proof is given for the Gauss-Markov theorem and statements of generalizations of the theorem. An extensive, but not exhaustive, bibliography of the literature is given with the object of making the theory more accessible to non-statisticians.
Storage and Retrieval of Data
Authors: Robinson S. C.
Published: July 2019

The most common method of recording surveying data is still the field notebook which, after its contents have been made use of or transferred to maps, is stored away. However, more efficient methods of recording and storing data must be considered when the volume of data reaches the point where it becomes economical to use modern methods of storage such as edge-punched cards, punched paper tape, magnetic tape and magnetic disc packs.

The author deals with the various methods of recording data and discusses the factors affecting the choice of a given system.
Aerodist in Geodetic Surveying in Canada
Authors: Tuttle A. C.
Published: July 2019

In 1962, the Topographical Survey Division of the Surveys and Mapping Branch, Department of Energy, Mines and Resources, acquired an aerodist survey system for use in the rapid extension of horizontal control for mapping in Canada. The following year, with the cooperation of the Geodetic Survey Division, the system was tested on a geodetic net in the Ottawa area for possible application in extending first-order horizontal control. Aerodist length measurements were made using the line-crossing technique. The results were most encouraging and in 1965, federal topographers and geodesists used aerodist trilateration to span Hudson Strait and northern Hudson Bay. In 1966, they established an extensive aerodist network in western Canada, connecting two previously established geodetic nets and observed test data on the continuous trilateration method for future analysis.

The paper describes the aerodist measurement procedure and the reduction of observed data, and discusses sources of error and the accuracy of aerodist measurements, based on analysis of work completed to date.

The paper also outlines future developments, including incorporation of a small electronic computer as part of the aerodist airborne unit, employment of electronic circuitry for obtaining meteorological data in the aircraft and a computer program to adjust continuous trilateration data. General factors affecting future applications and proposed future work are also included.
COSMOS — A FORTRAN Program for the Computation of Survey Material on the Spheroid
Authors: Perks Michael
Published: July 2019

A generalized description is given of the program COSMOS for the least squares adjustment of mixed survey data in terms of geographical coordinates. A comparison is made with GROOM, a program that COSMOS is designed to replace.

Some limitations of the program, the form of input and output and the operations performed in each phase are described. Brief mention is made of a similar program designed for the adjustment of plane survey data in terms of rectangular coordinates.
The Effect of Bodies of Water in Legal Surveying
Authors: Hadfield Colin D.
Published: July 2019

This paper was prepared to provide background material for the solution of problems involving flooded property and the difficulties of assessing conflicting evidence when positioning water boundaries. It was prepared specifically for the consideration of land surveyors in Ontario and was presented originally in Kenora, and later in North Bay, Windsor and Ottawa in 1967.
Torrens Land Titles System
Authors: Rozovsky Lorne Elkin
Published: July 2019

A proper land registration system, affording security of title at reasonable expense, is essential for the development of a dynamic and progressive economy. Such a system should indicate, quickly and cheaply, to interested persons what lands are being dealt with in any proposed transaction and what legal interests exist in those lands.

The present registry system in Nova Scotia does not provide this information readily. The remedy appears to lie in adopting a Torrens system of land titles similar to that which has already proven itself in the western provinces of Canada. The basic advantages of the Torrens system over the registry system are enumerated.
Reflections of a European on the Symposium on Land Registration and Data Banks
Authors: Rinner K.
Published: July 2019

Highlights from the history of surveying and mapping during medieval and modern times in Central Europe are cited to illustrate the ever increasing demand for better surveys and better maps for tax collection, land registration, civil engineering, military, scientific and other purposes.

In Austria, which has an area of 75,000 square kilometers and a population of 7,000,000 people, there is complete triangulation, from first to fourth order, and further densification to 500 meters is planned. Control and boundary points are durably marked and described by coordinates. A cadastral resurvey has been completed for some 540 of 5,000 communities.

Much of the work has been done by consulting engineers who are obliged to execute public orders during about 30 per cent of their working time. There are about 200 consultants and an equal number of state-employed survey engineers, with a ratio of three technicians per engineer.

From a summary of the main features of the new Austrian survey act, some recommendations are made for Canada. Specifically, there should be a network of control points based on a single datum; authorities should issue regulations governing the coordination of all surveys and the recording of all data; accuracy should be related to land value; administration and revision of surveys should be attended to by regional offices and, for large-scale maps and plans, a projection, which permits observed data to be directly related to map data should be chosen.

Several related problems, such as the development of a unified datum, are discussed.
A Data Bank for Use in the Social Sciences
Authors: Beaman Jay
Published: July 2019

A data bank system is important for urban studies. Some of the features that should be included in such a system are mentioned.

Urban areas have many social and engineering problems that require much study to understand and solve. A well-organized, flexible data bank system offers the means.

All data should be referred to geographic coordinates and, because of the quantity of data, an urban area should be partitioned into relatively small blocks. By use of coordinates, streets, boundaries, etc., can be defined as well as point data.

In addition to containing the necessary data, the system must be easy of access. The user must be able to obtain and process data by machine instructions that are easily learned. An example shows how data are called and manipulated to produce a type of map and to compute and tabulate certain statistics.

A flexible system is advocated. Limited logic can lead to restrictive studies and thinking. What is desirable at one time and place may not be suitable for another time or another place. Interdisciplinary thinking and the fact that experts disagree must be allowed for.
Data Banks and the Computer Analyst
Authors: Boyle A. R.
Published: July 2019

The computer analyst is the mainspring in the development of a data bank for automated cartography. To bring this development about, he must cooperate closely with the cartographer and the systems engineer.

The computer analyst must consider the bulk of the data and how these data are to be labelled. He must also reflect on how the data bank information is to be used and what manipulative processes it will be subjected to.

The analyst will set under way investigations by working groups of cartographers at various levels. These groups will deal in detail with cartographic policy and technical problems hitherto considered only in general terms. When the results of these investigations are known, the analyst will consult the systems engineer to ascertain whether the various specifications can be met. Problems likely to be discussed are the digitizing process, the form of displays necessary and the design of a versatile and accurate “pen’ for the drafting table. Finally, the analyst may have to consider the economics of the system so that he can advise the administrators who will be assessing the overall situation.
The Cadastre as the Basis of an Environmental Data System
Authors: Wallner H.
Published: July 2019

The function of the present cadastre, a program of cadastre reform and plans for a computer-based public information system in Sweden are presented. In the new cadastre register, approved by the Swedish government in 1968, a uniform notation system for both urban and rural “real estates” will replace the two systems now in use; parcels will continue to be described in a register and on maps; each parcel of land will be represented by one or more points defined by geodetic coordinates and other information, such as land surveyors’ decisions on boundaries, will be included. Digitization of all boundary and property information has started and is scheduled for completion in three to four years. Accuracy to one meter in urban areas and to 10 meters in rural areas is proposed.

For the computer-based information system, a large central computer online to display and printout units in regional offices is proposed. By merging computer fies, it will be possible to relate information from diverse registries. For example, in the population register a person will be identified by a census number as living on a real estate identified by a real estate number, which in turn is described by coordinates; hence each person can be associated with coordinates. Extension of this technique offers a flexible and economic solution to information retrieval for community planning, market analyses, transportation optimization and cultural, geographical and historical research.
Modern Surveying for Tomorrow’s Industry
Authors: Pegler Α. V.
Published: July 2019

Mining surveying techniques and equipment in North American mines have not kept pace with the development of modern production systems in the mines. In addition, there is a lack of properly-trained mining surveyors. Thirty-one per cent of the total survey personnel now employed in mines have been trained solely on the job, while there is not one graduate engineer in 61 per cent of the mining survey offices. Obviously, there is an urgent need in the mining industry for well-trained surveyors equipped with modern instruments, such as gyrotheodolites and lasers.