Posts

41)India's Republic Day 2021: Exactly how this year's celebration will change

India Republic Day -- Highlights -For the first time since 1966, there will be no chief guest within the Republic Day Parade. -The parade will be shorter this current year, instead of ending at the Red-colored Fort, it will culminate with National Stadium. -The Mini stry of Information and Biotechnology will depict the 'Vocal intended for Local' initiative of the authorities. India is all set to commemorate its 72nd Republic Time to honour the enactment of the Constitution of China which came into effect on The month of january 26, 1950. Traditionally, the highlight of Republic Time is the iconic parade this showcases IndiaĆ¢€™s military prowess and cultural heritage. But this year, the commemoration is going to be slightly different on account of the outbreak and events in the past year. Here is how Republic Day 2021 will be different: What cha nges have been made for the parade as a result of Covid? For the first time since 1966, there will be no chief invitee in the Rep

Surveying

Image
Surveying or land surveying is the technique, profession, art, and science of determining the terrestrial or three-dimensional positions of points and the distances and angles between them. A land surveying professional is called a land surveyor . These points are usually on the surface of the Earth, and they are often used to establish maps and boundaries for ownership, locations, such as the designed positions of structural components for construction or the surface location of subsurface features, or other purposes required by government or civil law, such as property sales. Surveyors work with elements of geometry, trigonometry, regression analysis, physics, engineering, metrology, programming languages, and the law. They use equipment, such as total stations, robotic total stations, theodolites, GNSS receivers, retroreflectors, 3D scanners, radios, inclinometer, handheld tablets, digital levels, subsurface locators, drones, GIS, and surveying software. Surveying has been an el

Definition

Image
The International Federation of Surveyors defines the function of surveying as follows: A surveyor is a professional person with the academic qualifications and technical expertise to conduct one, or more, of the following activities; to determine, measure and represent land, three-dimensional objects, point-fields and trajectories; to assemble and interpret land and geographically related information, to use that information for the planning and efficient administration of the land, the sea and any structures thereon; and, to conduct research into the above practices and to develop them.

History

Image
Ancient history edit Surveying has occurred since humans built the first large structures. In ancient Egypt, a rope stretcher would use simple geometry to re-establish boundaries after the annual floods of the Nile River. The almost perfect squareness and north–south orientation of the Great Pyramid of Giza, built c. 2700 BC, affirm the Egyptians' command of surveying. The Groma instrument originated in Mesopotamia (early 1st millennium BC). The prehistoric monument at Stonehenge (c. 2500 BC) was set out by prehistoric surveyors using peg and rope geometry. The mathematician Liu Hui described ways of measuring distant objects in his work Haidao Suanjing or The Sea Island Mathematical Manual , published in 263 AD. The Romans recognized land surveying as a profession. They established the basic measurements under which the Roman Empire was divided, such as a tax register of conquered lands (300 AD). Roman surveyors were known as Gromatici . In medieval Europe, beating the bounds ma

Equipment

Image
Hardware edit The main surveying instruments in use around the world are the theodolite, measuring tape, total station, 3D scanners, GPS/GNSS, level and rod. Most instruments screw onto a tripod when in use. Tape measures are often used for measurement of smaller distances. 3D scanners and various forms of aerial imagery are also used. The theodolite is an instrument for the measurement of angles. It uses two separate circles , protractors or alidades to measure angles in the horizontal and the vertical plane. A telescope mounted on trunnions is aligned vertically with the target object. The whole upper section rotates for horizontal alignment. The vertical circle measures the angle that the telescope makes against the vertical, known as the zenith angle. The horizontal circle uses an upper and lower plate. When beginning the survey, the surveyor points the instrument in a known direction (bearing), and clamps the lower plate in place. The instrument can then rotate to measure the be

Techniques

Image
Surveyors determine the position of objects by measuring angles and distances. The factors that can affect the accuracy of their observations are also measured. They then use this data to create vectors, bearings, coordinates, elevations, areas, volumes, plans and maps. Measurements are often split into horizontal and vertical components to simplify calculation. GPS and astronomic measurements also need measurement of a time component. Distance measurement edit Before EDM (Electronic Distance Measurement) laser devices, distances were measured using a variety of means. These included chains with links of a known length such as a Gunter's chain, or measuring tapes made of steel or invar. To measure horizontal distances, these chains or tapes were pulled taut to reduce sagging and slack. The distance had to be adjusted for heat expansion. Attempts to hold the measuring instrument level would also be made. When measuring up a slope, the surveyor might have to "break" (break

Types

Image
Local organisations or regulatory bodies class specializations of surveying in different ways. Broad groups are: As-built survey : a survey that documents the location of recently constructed elements of a construction project. As-built surveys are done for record, completion evaluation and payment purposes. An as-built survey is also known as a 'works as executed survey'. As built surveys are often presented in red or redline and laid over existing plans for comparison with design information. Cadastral or boundary surveying : a survey that establishes or re-establishes boundaries of a parcel using a legal description. It involves the setting or restoration of monuments or markers at the corners or along the lines of the parcel. These take the form of iron rods, pipes, or concrete monuments in the ground, or nails set in concrete or asphalt. The ALTA/ACSM Land Title Survey is a standard proposed by the American Land Title Association and the American Congress on Surveying an