Podcast
Questions and Answers
What is surveying as part of the science of Geomatics?
What is surveying as part of the science of Geomatics?
The science concerned with the measurement, representation, analysis, management, retrieval, and display of spatial information describing the Earth's physical features and the built environment.
What are the main jobs of a surveyor?
What are the main jobs of a surveyor?
A surveyor practices the science of measurement, assembles geographic information, and uses that information for planning and administration.
What historical records were found in Babylon related to surveying?
What historical records were found in Babylon related to surveying?
Clay tablets containing records of lands.
What technological advancements were motivated by military requirements during the World Wars?
What technological advancements were motivated by military requirements during the World Wars?
Signup and view all the answers
Which civilization established a school of surveying for town planning and map making?
Which civilization established a school of surveying for town planning and map making?
Signup and view all the answers
The pyramid of Giza is not aligned with the true meridian.
The pyramid of Giza is not aligned with the true meridian.
Signup and view all the answers
In surveying, the ________ phase involves selecting method, equipment, and final point locations.
In surveying, the ________ phase involves selecting method, equipment, and final point locations.
Signup and view all the answers
Name one type of surveying that takes into account the true shape of the earth.
Name one type of surveying that takes into account the true shape of the earth.
Signup and view all the answers
Which of the following is NOT a type of surveying mentioned?
Which of the following is NOT a type of surveying mentioned?
Signup and view all the answers
What is measurement?
What is measurement?
Signup and view all the answers
What does the term 'error' refer to in measurement?
What does the term 'error' refer to in measurement?
Signup and view all the answers
What is the correction in error calculation?
What is the correction in error calculation?
Signup and view all the answers
What are the sources of error in measurement? (Select all that apply)
What are the sources of error in measurement? (Select all that apply)
Signup and view all the answers
What is an example of a mistake or blunder?
What is an example of a mistake or blunder?
Signup and view all the answers
What characteristics define systematic or cumulative errors?
What characteristics define systematic or cumulative errors?
Signup and view all the answers
Which type of errors are produced by irregular causes out of the observer's control?
Which type of errors are produced by irregular causes out of the observer's control?
Signup and view all the answers
What is the degree of precision in measurement?
What is the degree of precision in measurement?
Signup and view all the answers
What is meant by accuracy in measurement?
What is meant by accuracy in measurement?
Signup and view all the answers
What is the mean?
What is the mean?
Signup and view all the answers
What is the median?
What is the median?
Signup and view all the answers
What is the mode?
What is the mode?
Signup and view all the answers
Study Notes
Geomatics
- The science of measuring, representing, analyzing, managing, retrieving, and displaying spatial information about the Earth and built environments.
- Includes surveying, geodesy, remote sensing, photogrammetry, cartography, geographic information systems, and global positioning systems.
Surveying
- The science and art of determining angular and linear measurements to establish the form, extent, and relative positions of points, lines, and areas on or near the Earth's surface.
Surveyor
- A qualified professional trained in the science of measurement, assembling and assessing geographic information, and using it for planning and land administration.
History of Surveying
- Babylon: Clay tablets containing records of lands.
- Egypt: The Great Pyramid of Giza is nearly a perfect square, with one side aligned with the true meridian.
- Ancient Greece: Eratosthenes calculated the circumference of the Earth.
- Rome (150 BC): Romans established a school of surveying to teach town planning, map-making, and road construction.
- 1400-1700: Significant developments in telescope design, standardization of measurement units, determination of longitude, and the writing of surveying instruments and reference books.
- 1900: World Wars I and II led to improvements in surveying equipment and operations.
Phases of Surveying
- Reconnaissance: Selecting survey methods, equipment, and final point locations.
- Fieldwork & Data Collection: Making measurements and recording data.
- Computing & Data Processing: Preparing calculations from recorded data to determine locations.
- Mapping or Data Representation: Plotting data to produce maps, charts, or other visual representations.
Uses of Surveys
- Establishing land boundaries.
- Fixing national and state boundaries.
- Charting coastlines, navigable streams, and lakes.
- Precisely locating reference points.
- Collecting data about Earth's magnetism.
Types of Surveying
- Plane Surveying: Assumes Earth's surface is flat, neglecting its spherical shape.
- Geodetic Surveying: Accounts for Earth's spheroidal shape.
Types of Surveys
- Control Survey: Establishes horizontal and vertical positions of reference points.
- Property Survey: Determines lot line lengths and directions, mapping them on the ground.
- Topographic Survey: Creates topographic maps showing terrain configuration and locations of natural and human-made features.
- Hydrographic Survey: Surveys bodies of water for navigation, water supply, or subaqueous construction.
- Mine Survey: Uses land, geologic, and topographic surveying principles to control, locate, and map underground and surface mining works.
- Route Survey: Surveys for transportation and communication routes like highways, railroads, canals, transmission lines, and pipelines.
- Construction Survey: Sets out plans for buildings and other structures during construction.
Errors & Statistics
- Error is the difference between the measured/calculated value and the true value.
- Correction is the negative of an error.
-
Sources of Error include natural, instrumental, and personal errors.
- Natural errors stem from variations in nature (e.g. magnetic declination, temperature changes, refraction).
- Instrumental errors arise from imperfections in instruments used (e.g. faults in construction or improper adjustments).
- Personal errors are caused by limitations in the observer's senses (e.g. sight, touch, hearing).
Types of Errors
-
Mistakes or Blunders are not errors, but gross mistakes.
- Common examples are reading the wrong graduation on a tape, omitting a whole length of tape, transposition of figures, misplacing a decimal point, incorrect recording of field notes, or sighting the wrong target.
-
Systematic or Cumulative Errors occur according to a deterministic system.
- Constant errors have the same magnitude and sign throughout the measuring process.
- Counteracting errors change sign but have constant magnitude.
- Common examples of systematic errors include equipment calibration issues, personal biases of the observer, and using incorrect units.
Random/Accidental Errors
- These errors are produced by irregular and uncontrollable causes.
- Vary randomly, without a deterministic system.
- Probability models must be used to analyze random errors.
Statistics: General Uses
- Statistics helps in decision-making by providing comparisons, explaining actions, justifying claims, predicting outcomes, and estimating unknown quantities.
- Statistics summarizes data for public use.
Precision vs. Accuracy
-
Precision refers to the consistency and refinement of measurement results.
- It measures the uniformity and reproducibility of the results.
-
Accuracy indicates how close a measurement is to the true value.
- It reflects the conformity with a standard.
Measures of Central Tendency
-
Mean: The sum of all values divided by the number of observations.
- It is the most probable value.
- It is influenced by all observations, particularly extreme values.
-
Median: The middle value when data is arranged in order.
- It is affected by the position of each item, but not by its value.
- It is a stable measure of central tendency.
-
Mode: The most frequently occurring value in a sample.
- It may not exist or be unique.
- It is not affected by extreme values.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the fascinating fields of geomatics and surveying in this quiz. Learn about the essential techniques and historical developments that have shaped these disciplines. Test your knowledge on key concepts, tools, and the role of surveyors in modern society.
