Measurement classification

Surveying is a science that studies how to determine the plane position and elevation of ground points, draw the terrain information of the earth's surface, and determine the shape and size of the earth. The contents include: general surveying, geodesy, geodesy, gravity surveying, topographic surveying, photogrammetry, engineering surveying and oceanography. ?

General measurement:

General surveying is the basic theory, technology and method to study small-scale surveying and mapping of the earth's surface. Taking the local surface of the earth as a plane without considering the influence of the curvature of the earth is the basis of surveying.

Geodesy:

It is a theoretical and technical subject to study and determine the shape, size, gravity field, global and local motion, geometric position and its changes of surface points. Its basic task is to establish a national geodetic control network, measure the shape, size and gravity field of the earth, and provide basic initial data for topographic mapping and various engineering surveys; It provides important information for space science, military science, crustal deformation research and earthquake prediction. According to different survey methods, geodesy can be divided into conventional geodesy, satellite geodesy and physical geodesy.

Marine surveying and mapping:

Marine surveying and mapping is the surveying and mapping of ocean and land waters, which belongs to the category of marine surveying and mapping.

Cartography:

It is a subject that studies the basic theory, design, compilation and reproduction technology, methods and applications of analog maps and digital maps. Its basic task is to compile various maps by using various survey results, and its contents generally include map projection, map compilation, map decoration and map printing.

Photogrammetry:

It is a subject that studies the use of electromagnetic wave sensors to obtain image data of targets, extract semantic and non-semantic information from them, and express them in the form of graphics, images and numbers. Its basic task is to process, measure and interpret photographic photos or remote sensing images to determine the shape, size and position of objects, and then make maps. According to the different ways of obtaining images and remote sensing distance, this subject is divided into ground photogrammetry, aerial photogrammetry and space remote sensing measurement.

Engineering survey:

Definition 1: Engineering survey is a subject that studies all kinds of survey work in the planning, design, construction and operation management stages of various projects.

Various projects include: industrial buildings, railways, highways, bridges, tunnels, water conservancy projects, underground projects, pipeline (power lines, oil pipelines) projects, mines and urban construction. General engineering construction is divided into three stages: planning and design, construction and operation management. Engineering survey is to study all kinds of survey work carried out in these three stages.

Definition 2: Engineering survey mainly studies the theories, methods and technologies of terrain and related information collection and processing, construction lofting, equipment installation, deformation monitoring, analysis and prediction, as well as the management and utilization of surveying and engineering related information in various stages of engineering, industrial and urban construction and resource development. It is the direct application of measurement in national economy and national defense construction.

Definition 3: Engineering Surveying is an applied discipline that studies the theory, method and technology of measuring and describing specific geometric entities in the earth space (including ground, underground, underwater and air) and realizing the layout of abstract geometric entities. Mainly in construction engineering, machinery and equipment.

Measuring instruments:

Research on the manufacture, improvement and innovation of measuring instruments.

Terrain:

It is a subject that studies the theory, method and technology of how to draw the related information such as features and landforms in local areas of the earth's surface into topographic maps. Topographic mapping can be divided into analog mapping and digital mapping according to different mapping methods.

Surveying is a science that studies the shape and size of the earth and determines the position of the ground (including air, underground and seabed). It is a science and technology that studies the collection, processing, management, updating and utilization of information related to geographical spatial distribution on the whole earth and various natural and man-made objects on its surface and outer space. Is to determine the location of space points and their attribute relationships.