HOW TO CALCULATE SCALE FACTOR IN LAND SURVEYING!
HOW TO CALCULATE SCALE FACTOR IN LAND SURVEYING!
πSurveyor αα ္ေαာα္α Scale Factor αြα္αα္း αာေαးαိုα αျαား Juniors ေαြαα္း αိေα ျαα္းα‘αိုααွာ ျαα္αα္ αα္ျααိုα္αါαα္
π ေαွးα₯ီးα ြာ αααာေျαျαα္α‘αံုးαို αိαားααါαα္၊ αααာေျαျαα္ေααα α‘αိα့္α‘ျαα့္ ααီαာαဲ့ ေαာα္αα္းေαြ၊ α်ိ ုα့္αွα္းေαြαို αα္αΏαီး α ံαα္αွα္α်α္ ( Standard) α‘ေααဲαα်α္းαα½ွαα္αα္ေαα်α္ႏွာျαα္α‘ျαα့္ ( Mean Sea Level) or 'MSL' αိုαာ αααာ့ αα္ေααာαွာ ျαα ္ျαα ္
αααာ့ααိုαေα Distance ေαြ (Approximately) αူαီαါαα္ ( α‘ီေαြαာα‘α်α္းαဲα αα္αိုးα ြα္း α‘α်α္း αα αိုα္αြာေααဲ့ αααာ့α‘αြα္α‘α ားαဲα ႏွိ ုα္းα ာαα½ွα္ αေျαာαေαာα္αဲ့α‘αြα္ αααာααီးαို Near perfect Sphere αိုααဲ αူαါαα္)
πα‘ဲαီ αααာ့ MSL ေαြαို α ိα္αူးαα₯္α်α₯္း ( Imagery Line) αα ္αုαဲα αα္αိုα္αဲ့α‘αါ ααာαဲ့ Near Perfect Sphere ( α α္αံုး) αို GEOID αိုαေαααါαα္
πααα»ာ့ေျααံု 3D features ေαြαာ α‘αΎαα္းα်α္းα‘ားျαα့္ α‘ဲαီ Geoid Surface ( α α္αံုး)ေαααွာ αα္αွိေααα္αိုα αားαα္αိုαααါαα္
πα‘ဲαီ αα္ေαြααွာ α‘αံုး α်α္ႏွာျαα္ CURVE SURFACE αို
FLAT PLANE ျαα ္αဲ့ α ာαြα္ေααα ေျααံုα‘ျαα္α FLAT SURFACE α‘ေααဲα αα္ျααဲ့α‘αါ On-ground αိုα္းαားαဲ့ Points ( i.e Locations) ေαြαဲα ေျααံုα ာαြα္ေαα
α‘ျαα္ααွာ αိုးα ားျα ု αα္αားαဲ့ Points ( Locations) ေαြ α‘αα္းαα္ αြဲαြဲαွ ုျαα ္αြားαါαα္၊
πCurved surface ေααα Data αို Flat surface ေαα ( αα့္ေαာ္αဲ့ α ေαးα်ံ ုααΏαီး ) αα္αိုα္αဲ့α‘αါ/ αα ္αα္း Map Projection α် αိုα္αဲ့α‘αါ /αα ္αα္း α‘αံုးα်α္ႏွာျαα္ေααα αံုαိα္ေαြαို α‘ျαα္αα်α္ႏွာျαα္ေαααွာ----αုα္αွα္ααα္α‘αံုးေααα αံုαိα္ေαြαို ေαာα္α αုα္αွα္ျαα α္ αီးααိုα္αိုးααို ( Projector αီးαိုးααို Projection α်) αΎαα့္αဲ့α‘αါ αံုαိα္ေαြ αံုαြဲααႈ ( DISTORTION)ျαα ္ αြားαါαα္
πα‘ဲαီαို αံုαြဲααြားαဲ့α‘αါ (α‘αူးαျαα့္ α§αိαာααီးααီးαိုα္းαားαဲ့α‘αါ ) On-ground Data αို Map ေαααα္αဲ့α‘αါ ေααာαြဲ ( displacement) ျαα ္αြားαာေαြ
αိုα္းαာαဲ့ α§αိαာ α်α္αα½ွα္α်α္
αေαာα္ ျαα္αိႇαဲ့( Correction ) ααုα္αα½ွα္ αိုαို Displacement error α်ားαα္αါαα္
παိုαα္းαို ျαα္ေαာα္αါαα္၊
αααာ့ Geoid Surface / MSL αေαα½ွာα္αွာ αα ္αိုα္αြားαိုα္း α αααΌαα္α α‘αံုးαွိαါαα္ ( ျαα္αာေα‘ာα္ေျαာααα½ွα္ေαာ့ αြα္ေαာ္αိုααာ αα္αα္ျαα္ αြα္αႊα့္αြားαဲ့ αေαၤာαα ္α ီးαဲα αြα္αိုα္αိα္αို α‘ေαးαΎαα့္αွα္ေျαာα္းαဲα αΎαα့္ေααဲ့α‘αါ αα ္αိုα္αြားα‘αΏαီးαွာ αူααြα္αိုα္αိα္α ေα‘ာα္αို α αααΌျαဳα္αြားαα့္ αေαာαါαဲ၊
παααာေျαααီးα αံုးαα္းေααိုααါ)
πα‘ဲαါαို αα½ြα္ေαာ္αိုα Highway or Large Area Map α‘αြα္ αိုα္းαာαဲ့α‘αါ On-ground data αို Grid Map ေαααα္αဲ့α‘αါ Distance ေαြ α‘αီးα α္αံုးαူေα‘ာα္ ေαွးα₯ီးα ြာ αိုα္းαာ αြα္α်α္αΏαီး On-ground Distance αဲα Grid Map Distance α α်ိဳ ုးαို α‘ျαα္α‘αွα္ αွα္αα္α ြာ α်ိα္αα္ေαးαα့္ αူααα္αိုα္αာ α§αိαာα‘αြα္ Constant ( αိα္းေα)αα ္αု αိုα‘α္αာαါαΏαီ
πα‘ဲαီ Constant αာ ααα္ေαာ့ SCALE FACTOR αါαဲ၊
παေααေαα္αွာ α‘α်ားαα္αံαားαဲ့ UTM Map αိုα်ိ ုးေααα Point α αု α‘αြာα‘ေαးαဲα α‘ဲαီ the same points α αုαဲα ေျαျαα္ေααα α‘αြာα‘ေαး α αုαို αိႇαူ ( Adjust) αုα္αာαါαဲ
πေαွးα₯ီးα ြာ αိαိαိုα္းαာေααဲ့ α§αိαာ αဲα αα္αွားαဲ့ ေျαျαα္α‘αွα္α‘αား Land Marks α αုαို Google map / Update one-inch map αွာ αွာαားαါ--(α₯ααာ αα္းαီးαိုα္ α αိုα္αိုα်ိဳ ုး/ building corners αိုα်ိ ုး )
πGoogle ေαααွာαိုαα½ွα္ α‘ဲαီ Distance αို Ruler αဲααိုα္းαါ၊
✌36.03 m αိုαါα ိုα၊
πMap ေαααွာαိုαα½ွα္ αα္αိုα္αာ Point A , B ( e.g.) αဲα Coordinates ေαြαို Polar αဲα Calculator αွာαြα္αွာ( αိုαααုα္) ေαာ္ေααံαဲαα်αိုα္းαΏαီး αူαေျααံုα ေαးαဲαေျαာα္(multiply)αα္ ααါαα္၊
πMap ေααα distance ααΏαီးαဲ့α‘αါ ααα္ α‘ဲαီ Land marks α αုα‘αြာα‘ေαးαို Total staion αဲααိုα္းαΏαီးαွα္αားαါ၊ ✌36.00 m αိုαါα ိုα၊ ( T.S αဲα Prism constant αို T.S screen αα္α်α္αဲα On-ground Tape measure αြα္αိေαာα္αီေα‘ာα္ αိႇαားααါαα္)
πေαာα္αံုးα‘αα့္α‘ေααဲα α‘ဲαီ Grid Map ေααα Distance αို On-ground ေααα Measured Distance
αဲαα ားαα½ွα္ (divide) αα½ြα္ေαာ္αိုα αိုα်α္αဲ့ SCALE FACTOR αိုαာααါαΏαီ
π
Scale Factor= Map dist/Ground dist
πS.F.= 36.03/ 36
= 1.0008333
✌S.F = M.D/ G.D
πα‘αα္α αံုေααα္းαို α‘ႏွα ္
α် ုα္ေαာ္ αα½ြα္ေαာ္αိုααွာ ground distance distance αိαားαΏαီး
Map distance αို αိαိုαα½ွα္ α‘ဲαီ ground distance αို Scale factor αဲα ေျαာα္( multiply) ααွာျαα ္αΏαီး ၊
αိαားαဲ့ Map distance αα ္αုαို ground distance αα္ေαာα္αဲ αိα်α္αα½ွα္ေαာ့ α‘ဲαီ Map distance αို Scale factor αဲαα ား ( divide) ααါαα္၊
πα‘αα္ααα္ျαα်α္αာ α₯ααာαာျαα ္αΏαီး αα္ေαြα
On-ground αွာေαာ့ Test distance αာ ေα αααα αα္α ( ~ 300m)
T.S αα ္αါ ေαာα္းေαာα္းαα္ႏိုα္αဲ့ Distance α်ိ ုးαိုαα½ွα္ αα့္ေαာ္αα္ αα္αါαα္၊
πေα‘ာα္αံုးαွာ Scale Factor αြα္αα္း --Googling αုα္αားαဲ့ English version αိုαα္း Link ေαးαားαါαα္
παα½ြα္ေαာ္αα္း ေα့αာαဲαိုα
αိုα‘α္α်α္α်ားαွိαα½ွα္ ααာαွα္α်ားေαာα္ျαေαြးေႏြးေα α်α္αါαα္
ေαးα ားα်α္-Than Soe Aung
HOW TO CALCULATE SCALE FACTOR IN LAND SURVEYING!
http://www.gpslandsurveying.com/how-to-calculate-scale-factor/
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