Geobide, ED50 da ETRS89 Canza Tsarin Tsarin Tsarin Mulki
Samun amfani don bi iyawa na Geobide Suite, za mu ga zaɓuɓɓuka don canzawa Tsarin Gida. Ban sha'awa ga wadanda suka dole ne canza tsakanin daban-daban Datum a cikin wannan hali za mu ga yadda za a yi shi tare da ED50 da ETRS89 tsarin shi ne kusan guda harka a Latin America tsakanin NAD27 da WGS84.
An canza bayanai?
Wannan ba batun Google Earth ba ne, inda za'a yi canje-canje, ana juye hotuna da yawa, wani abu da za a iya duba su a kan kari tsakanin daban-daban daukan; Koyaya, a ƙasashe da yawa, jihohi ko al'ummomin masu cin gashin kansu, cibiyoyin jama'a sun ba GoogleEarth hotunan su tare da daidaitaccen yanayin, tare da rashin amfanin GoogleEarth yana amfani da WGS84 a matsayin Datum na yau da kullun, don haka amfani da bayanai a cikin wani tsarin yana buƙatar sauyawa. Canjin ya dogara ne da farko akan ma'anar kansa amma kuma akan yankin da muka sami kanmu. Abin da ya sa keɓaɓɓun tsarin ba sa samar da sigogi na musamman na kowane yanki.
Bari mu dauki misali canji na ED50-30N (EPSG: 23030) zuwa ETRS89-30N (EPSG: 25830) don Navarra, da Spain. Ma'anar canzawa ta canzawa tana da matsayi daban-daban na daidaito dangane da yankin da ake amfani da shi. A saboda wannan dalili, akwai wasu ƙarin sigogi, waɗanda ba sa cikin ma'anar janar kuma waɗanne a cikin Navarra misali wasu ne amma a cikin Asturias suna iya samun wasu ƙimomin daban.
Idan muka kalli hoton da ke sama wanda aka ɗauke shi daga Geomap, zamu ga taswira mai ɗauke da layuka biyu (orthophoto da kunshi) sun haɗu da juna. Sakamakon ƙaddamar da Navarra Cadastre a cikin ED-50N a kan tashi wani Layer na GoogleMaps a cikin WGS84 da sakamakon sakamako wanda ya shafi sakamakon da aka bayyana a cikin sakin layi na baya.
A koyawa Geobide koyawa, daga wanda muke yin wannan labarin yanzu yana buga aƙalla hanyoyi 4 don gyara shi,. Tare da Geobide, yanzu yana yiwuwa a nuna juyawar datum don canji tsakanin Tsarin Tsarin Tsarin ta hanyoyi daban-daban guda huɗu:
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Tsarin Gyara na Generic:
Wannan zaɓin yana amfani da canji na canzawa ba tare da sigogi na sararin samaniya ba, kuma mafi kuskure ne. Ga Navarra misali, daga ED50 zuwa ETRS89 yana da kuskure na ~ 100-200m a x da y. (Tunawa cewa wannan ba ya shafi tsarin daidaitawa tare da daidaitattun ma'auni).
Quite kama shi ne yanayin da NAD27 da WGS84 tafiya da 202 mita arewa da kuma 6 mita gabas a Jamhuriyar yankin canje-canje kamar yadda ka canza latitud, ko da yake shi ne kawai gagarumin a latitud shi zo daga Ekwado yayin da da tsawon kawai zo daga karya ne wannan.
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Canzawa Amfani da Grid NTv2:
Wannan zabin yana amfani da grid tare da dabi'u don gyara fasalin ta hanyar linzamin linzamin kwamfuta. Wannan zabin ya fi dacewa da hanyar farko kuma an karɓa ta hanyar IGN. Tabbatacce, ba shakka, idan muna da grid don yankinmu.
Aikace-aikace na Tsarin Yanzu suna ba da layukan sadarwar biyu da IGN ya bayar don Spain, wanda ya shafi Yankin Peninsula da Tsibirin Balearic, kuma an buga su a 2003 da 2009. Mai amfani zai iya zaɓar grid ɗin da zai yi amfani da shi.
A Intanit zaka iya samun grid da yawa, har ma a duk duniya, amma ta girman ba a samun su ta atomatik a cikin saukar da aikace-aikacen Geobide.
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Hanyar Molodensky (hanyar 3-sigogi):
3 yana amfani da ƙimar dabi'u a asali tsakanin ellipsoids. Mai maye gurbin da aka tsara ta hanyar IGN don Spain.
Hanyar Bursa-Wolf (hanyar 7-sigogi)
Wannan canji yana amfani da dabi'u 7 don canzawa tsakanin ellipsoids. Siffofin da za a shigar sune: Offset (Dx, Dy, Dz), Juyawa (Rx, Ry, Rz) da Faɗakarwa Factor (μ)
A cikin aikace-aikace Tsarin 3 wizards an riga an saita su da shawarar ta hanyar IGN domin Arewa maso yamma, tsakiya da gabas ta yankin, daidai da haka.
Resultados
Yayin da kake ganin sakamakon bazai bambanta tsakanin hanyoyin 3 ba, amma a da farko. Abin da ya sa dole ne ka san idan sauyawa yana buƙatar kowane daga cikin waɗannan zaɓuɓɓukan ci gaba.
Daga cikin ED50-xxN (EPSG: 230xx) da kuma tsarin ETRS89-xxN (EPSG: 258xx) a yankin na Spain kanta ya kamata a yi amfani da matsayin Datums / ellipsoids ED50 da ETRS89 / WGS84 ba m.
Alal misali, idan Geomap ba wadannan m data sa, data daga Navarra a ED50-30N (EPSG: 23030) reprojected a kan gardama a kan data miƙa ta Google Maps (ellipsoid WGS84) zai koma. Don shige yadda ya kamata, shi wajibi ne don amfani da mafi daidai-canje da cewa an riga an bayyana.
Yana da kyau sosai a gare ni cewa Geobide na kokarin ƙaddamar da damar yin amfani da tsarinsa, amma har ma ya rubuta a cikin ɗan taƙaitaccen bayani akan wannan tambaya tun lokacin da zai iya rinjayar da yawa da kuma ingancin aikin, ban da kawai gane shi ba wani kokarin.
Ya zuwa yanzu, dukkanin wannan an haɗa ta atomatik cikin engine, amma kamar yadda abokan abokai na Gidanmu suka gaya mana, bukatun masu amfani sun haifar da shi a cikin aikace-aikace don mai amfani da kanta ya san shi har ma ya canza saita, ko saita wani don yankinka na aikinka.
Canji na ellipsoidal / geoidal Heights
A cikin sabon fasalin, an canza maɓallin lissafin mahimmanci / geoid mai banbanci domin mai amfani zai iya zaɓar tsarin geoid yanzu don amfani.
Fayil na PRJ Fayil
Kuma a karshe, wani canjin da ya yi daidai a cikin ku yunkurin yin hulɗa tare da tsarin OGC ko ayyuka na shirye-shiryen jama'a. Fayil PRJ da Gebot ya haifar suna a cikin sunan OGC WKT, wanda shine daidaitattun ƙididdigar da yawa daga kayan aikin CAD / GIS. Ba haka ba don aikace-aikacen ESRI, wanda PRJ, ko da yake suna ƙunshe da ma'anar ilmin lissafi kamar yadda ya dace, ƙayyadad da tsarin sarrafawa daban.
Alal misali:
A cikin abun ciki na fayil na PRJ na OGC, tsarin tsarin ETRS89-30N (EPSG: 25830) an bayyana tare da sunan code "ETRS89 / UTM zone 30N"; da aikace-aikace ESRI, maimakon haka, sun kira shi "ETRS_1989_UTM_Zone_30N". Idan a ArcGis mun haɗu da yadudduka tare da PRJs a cikin lambobi biyu ɗin wannan software za ta yi canji na sararin samaniya ko da a yayin da ma'anar ilmin lissafi na Coordinate Systems ya kasance daidai.
Kula da wannan m, Geobide ya ba da wani sabon zaɓi a cikin zaɓin tsarin bincike don haka mai amfani zai iya nuna idan yana so Tsarin Gudanarwa tare da PRJ a cikin style EPSG ko style ESRI.
