 Hello friends, today we are going to discuss on topic principles of serving, myself, Bipin Patil, assistant professor, department of civil engineering, Walchern Institute of Technology, Solapur. So my dear friends, these are the learning outcomes for today's session. So at the end of this particular session, student will be able to first one, explain serving means what do you mean by serving, types of serving, basic types and principles of serving. So throughout this particular session, we will discuss regarding serving the types and principles. First one, what do you mean by serving? What is serving? My dear friends, serving is the art of measuring first one distances, angles and positions. It may be above the ground level, it may be below the ground level on or near the surface of earth. In short, serving is the art of measuring the distances, angles and positions on or near the surface of the earth. So for that, we require different instruments. So first one, dumpy level is there. Atto level is there. Then tilting level is present. Theodolite is present. Total station. Such a list of instruments are present to carry out this particular serving work. Uses of serving, why serving is essential. So few points I already listed here, one by one we will discuss. First one, serving is essential to measure the areas. Suppose land is present to measure the areas of this particular land, we require serving. Building is present to identify the area of this particular building, serving is essential. Second point, to prepare a different types of maps. So in that particular maps, we just considered topographical condition of earth. Topographical map we require and this map you have to prepare by using serving. Cadastral map is there. Engineering map is also present. Engineering maps to identify the boundary conditions, area, periphery of your building. Land area is there. Military map to prepare a small plan regarding any type of work we require serving work. So for that we are using military map. In military work also it is essential. Contour map, basically two types of contouring are favorite or we say very essential. Block contouring work, radial contouring work. So for that we require serving work. And last one that is very important, geological map. To prepare a geological condition of earth surface, we require serving work. The next one, different building works. Different government projects we require serving work. It is very useful for the purpose of designing the projects. So which types of projects are present? First one, dam is there. Construction of a dam, construction of a canal, construction of a veer, construction of a roads, railways, airports, serving is essential. Primary survey, preliminary survey work and after that this particular project you have to finish it. So for that we require serving work. Next one, it is used to making of a plans in connection with illegal documents. So first you just study the area, study the maps and after that you have to prepare a plan. And these particular plans you are using for government work. Then last one, any disputes are present in a property by two parties or third one party. So these particular disputes, you can easily solve by using serving. So certain plans may be used as a legal documents to rectify these particular disputes regarding properties and this particular serving plays most important role during these particular cases. Next one, these are nothing but the types of serving. First one, plan serving. Second one, ziotic serving. So few points already mentioned. Our surface is considered plain in x and y dimension, x and y direction. So we called as plan serving. And same thing if the earth surface is considered spherical and reolation. So for example ellipsoid is there so we called as ziotic serving is there. Z that is third dimension height reference to the mass spherical surface of the earth from mean sea level. And third dimension this height is referred similarly from mean sea level but from the surface of earth. Last one, corrections applied to the curvature is for long strips that is nothing but for high wave work. And here very precise survey work boundary conditions and costal networks are present. So in such cases we are using ziotic serving is there. Lace area is available for plan survey. More area is present so two, three hectares so we are using ziotic serving work. Next one these are nothing but the principles of serving. Basically two principles are present. First one to work from the hole to the part. And second one to locate a new station point by at least two measurements. It may be your linear it may be angular from fixed reference points. Let us we discuss first principle to work from hole to the part. Refer this particular figure. Land area is present. Your first task is irregular shape land is present. So you just first fix your control points. That is nothing but you just observe the whole area is first enclosed by main station that is nothing but A, B, C, D and so on. And these station points you just join by using one line the line we called as main survey lines. Sometimes we called as controlling station and controlling lines are there. Further the area is divided into number of parts by forming a well conditioned triangles. Now you just observe A, B. So the control lines are over main survey lines. These lines these are nothing but you just bifurcate the whole area into number of triangles. Now you just observe if I join B a line so one triangle is present second third four just like number of triangles are present. Now the main survey lines are measured very accurately by using standard chain engineering chain metric chain gunter chain or tapes. Then the sites of triangles are measured A to B, B to C, C to D. So A to B so and so distance is present B to C the distance is one so so at last okay periphery of this particular control stations you just measured it and then you just move towards your the remaining parts that is nothing but the triangles sites of this particular triangles. So what are the errors are present A to B small error is there B to C very small error is there. So when we are identifying the area from work to the work from the whole to the part so the less areas are present in your this particular picture. Similarly to work from the whole to the part first few errors are present in that how to overcome this it prevents accolation of our errors. If there is any error in the measurement of any side of a triangle then it will not affect the whole work and the error can always be detected and eliminated. Suppose instead of that it has started from to work from part to the whole so whatever the errors are present in this particular part same errors are carry forward in next line. So at last tremendous error is present to avoid that we are moving to work from whole to the part not to work from part to the whole similarly what are the changes are present when we start our work to work from the part to the whole if the reverse process from part to the whole is followed then the minor errors in a measurement will be magnified in the process of expansion and these errors will become absolutely uncontrollable means see a to b 0.1 meter error is there so b to c 0.2 meter c to d double 0.4 meter is there d to e 0.8 meter these errors are cumulatively increases and because of that at last the outputs are very worst. So to avoid that we are using to work from whole to the part not part to the whole. Second principle is present to locate new station by at least two measurements linear or angular from fixed reference point so a b is fixed one linear measurement c point we are going to establish here so a to b is fixed one a to c you just prepare 1 r or fix the dimension b to c by using linear measurement suppose the distance is 10 meter 10 meter so from a to c 10 meter we prepare 1 r b to c 10 meter we prepare 1 r and establish new station point. Second one one angular measurement and one linear measurement a b is fixed angular measurement so on so this particular angle is present 75 degrees there so from 75 degree we prepare one line and from b to c this is nothing but your new established point. So here you just prepare the distance linear measurement prepare this 10 meter distance and mark it here and establish third point similarly a to b to angular measurement theta theta theta 1 theta 1 so 45 degree 45 degree cross section intersection point it produce you the new established point so the cross mark interpolation between these two particular points easily you can identify third so the new station should always be fixed by at least two measurement from fixed reference points linear measurement refers to horizontal distance measured by either chain or tape and angular measurement is carried out by using prismatic compass or theodolite so easily you can establish third one point either angular or linear measurement so my dear friends now you just try to pause the video and try to give the answer of this particular question this is the answer of this particular question to prepare this particular video I refer these are the references for my video thank you