FUNDAMENTALS OF SURVEYING (LECTURE)

HABITS OF ACCURACY, INDUSTRY AND RELIABILITY

IT WILL DEVELOP____________________.

PROBABLE ERROR

a quantity when added and subtracted from the most probable value, defines a range within which there is a 50% chance that the true value of the measured quantity lies inside (or outside) the limits thus set.

MAY 20, 1875

a treaty was signed, which created a permanent international bureau of weights and measures.

SYSTEMATIC ERRORS

also known as cumulative errors

INDUSTRIAL SURVEYS

also known as optical tooling

RELATIVE PRECISION

also known as relative error

GEODETIC SURVEYING

are surveys of wide extent which take into account the spheroidal shape of the earth.

CITY SURVEYS

areas in and near a city for the purpose of planning expansions or improvements, locating property lines, fixing reference monuments, determining the physical features and configuration of the land and preparing maps.

PERSONAL ERRORS

arise principally from limitations of the senses of sight, touch and hearing of the human observer which are likely to be erroneous or inaccurate.

THEORY OF PROBABILITY

assumes an infinite number of occurrences of all possible events.

MOST PROBABLE VALUE

basic assumption is that mpv of a group of repeated measurements made under similar conditions is the arithmetic mean or the average.

NATURAL ERRORS

beyond the control of man

ERRORS

can be minimized by careful work and by applying corrections.

MISTAKES

caused by a misunderstanding of the problem, inexperience, or indifference of the surveyor.

NATURAL ERRORS

caused by variations in the phenomena of nature such as changes in magnetic declination, temperature, humidity, wind, refraction, gravity, and curvature of the earth.

CADASTRAL SURVEYS

closed surveys which are undertakes in urban and rural locations for the purpose of determining and defining property lines and boundaries, corners and areas.

DIRECT MEASUREMENT

comparison of the measured quantity with a standard measuring unit or units employed for measuring a quantity of that kind.

MEASUREMENT

concentrated on angles, elevations, times, lines, areas and volumes

ERRORS

defined as the difference between the true value and the measured value of a quantity.

PRECISION

degree of refinement and consistency with which any physical measurement is made

RESIDUAL

difference between any measured value of a quantity and its most probable value.

INSTRUMENTAL ERRORS

due to imperfections in the instruments used

PERSONAL ERRORS

eliminated by employing appropriate checking of procedures in the taking and recording of measurements.

FORESTRY SURVEYS

executed in connection with forest management and mensuration and the production and conservation of forest lands.

ACCURACY

implies the closeness between related measurements and the expectations

MISTAKES

inaccuracies in measurements which occur because some aspect of a surveying operation is performed by the surveyor with carelessness, inattention, poor judgement and improper execution.

ACCURACY

indicates how close a given measurement is to the absolute or true value of the quantity measured.

METER

international unit of linear measure

ROUTE SURVEYS

involves the determination of alignment, grades, earthwork quantities, location of natural and artificial objects in connection with the planning, design, and construction of highways, railroads, pipelines, canals, transmission lines and other linear projects.

THEORY OF PROBABILITY

it does not in any way determine the magnitude of systematic errors which may also be present

RELATIVE PRECISION

it is expressed by a fraction having the magnitude of the error in the numerator and the magnitude of a measured quantity in the denominator

TOPOGRAPHIC SURVEYS

made for determining the shape of the ground, and the location and elevation of natural and artificial features upon it.

PHOTOGRAMMETRIC SURVEYS

makes use of photographs taken with specially designed cameras either from airplanes or ground stations.

ERRORS

may also be caused by the imperfections of the senses of the person undertaking the measurements or by natural causes.

ERRORS

may be caused by the type of equipment used or by the way in which the equipment is employed.

ACCIDENTAL ERRORS

minor importance than systematic errors since they are variable in sign and are of compensating nature.

MOST PROBABLE VALUE

mpv

ACCIDENTAL ERRORS

no absolute way of determining or eliminating them since the error for an observation of an quantity is not likely to be the same as for a second observation.

SYSTEMATIC ERRORS

occurs due to instrumental factors, natural causes, and human limitations of the observer.

PROBABILITY

the number of times something will probably occur over the range of possible occurrences

MEASUREMENT

the process of determining the extent, size or dimensions of a particular quantity in comparison to a given standard.

PLANE SURVEYING

the type of surveying in which the earth is considered to be flat surface and where distances and areas involved are of limited extent that the exact shape of the earth is disregarded.

INSTRUMENTAL ERRORS

the wear and tear of the instruments will likely be a cause for errors

CADASTRAL SURVEYS

these surveys are also made to fix the boundaries of municipalities, towns and provincial jurisdictions.

PLANE AND GEODETIC SURVEYING

two general classifications

SYSTEMATIC AND ACCIDENTAL ERRORS

types of errors

DIRECT AND INDIRECT MEASUREMENT

types of measurements

CCCFHIMPRT

types of surveys

INDUSTRIAL SURVEYS

use of surveying techniques in ship building, construction and assembly of aircraft, layout and installation of heavy and complex machinery and in other industries where very accurate dimensional layouts are required.

THEORY OF PROBABILITY

useful in indicating the precision of results only in so far as they are affected by an accident errors

RESIDUAL

v=x-x(or mpv)

METER

was proposed sometime in 1789 by french scientists.

INDIRECT MEASUREMENT

when it is not possible to apply a measuring instrument directly to a quantity to be measured.

SYSTEMATIC ERRORS

which will always have the same sign and magnitude as long as field conditions remain constant and unchanged.

SURVEYS

COVER A WIDE RANGE IN SCOPE AND COMPLEXITY.

MINE SURVEYS

performed to determine the position of all underground excavations and surface mine structures, to fix surface boundaries of mining claims, determine geological formations, to calculate excavated volumes, and establish lines and grades for other related mining work.

SURVEYING

planning and design are based on the results of surveys and construction is controlled by surveying

PRECISION

portrayed by the closeness to one another of a set of repeated measurement of a quantity.

ACCIDENTAL ERRORS

purely accidental in character

RELATIVE PRECISION

ratio of the error to the measured quantity is used to define the degree of refinement obtained.

RESIDUAL

referred to as the deviation

MOST PROBABLE VALUE

refers to a quantity (based on available data) which has more chances of being correct than has any other.

INSTRUMENTAL, NATURAL AND PERSONAL ERRORS

sources of errors

HYDROGRAPHIC SURVEYS

surveying streams, lakes, reservoirs, harbors, oceans and other bodies of water.

CONSTRUCTION SURVEYS

surveys which are undertaken at a construction site to provide data regarding grades, reference lines, dimensions, ground configuration, and the location and elevation of structures which are of concern to engineers, architects and builders.

SURVEYING

the art and science of determining angular and linear measurements to establish the form, extent and relative position of points, lines and areas on or near the surface of the earth or on other extraterrestrial bodies through applied mathematics and the use of specialized equipment and techniques.