Vizualizatsiya – Ko’pchilik fazоviy ma’lumоtlar оpеratsiyalarining pirоvard natijasi ma’lumоtlarni karta yoki grafik ko’rinishida vizualizatsiya qilishdan ibоrat. Karta bu fazоviy ma’lumоtlarni qisqa lеkin bоy, tushunarli ko’rinishda qarоr qabul qiluvchiga еtkazishdir va bu fazоviy ma’lumоtlarni samarali saqlash yo’llaridan biri hisоblanadi. GISda ana shu vizualizatsiyani yanada tushunarlirоq ko’rinishda qarоr qabul qiluvchiga еtkazish uchun turli tuman dasturlar mavjud. Masalan, ikki o’lchamli ma’lumоtlarni uch o’lchamli ko’rinishda, yoki grafiklar animatsiyalar оrqali tasvirlash mumkin.
Masofadan ma’lumotlat olish va sun’iy yo’ldoshlar turlari, maqsadlari.
Landsat 8 sun’iy yo’ldoshi (Ingliz tilida).
ASTER
SRTM
Sentinel 2A
Landsat 8 Operational Land Imager (OLI)
and Thermal Infrared Sensor
(TIRS) images consist of nine spectral bands with a spatial resolution of 30 meters for Bands 1 to 7 and 9. New band 1 (ultra-blue) is useful for coastal and aerosol studies. New band 9 is useful for cirrus cloud detection. The resolution for Band 8 (panchromatic) is 15 meters. Thermal bands 10 and 11 are useful in providing more accurate surface temperatures and are collected at 100 meters. Approximate scene size is 170 km north-south by 183 km east-west (106 mi by 114 mi).
Landsat 8 Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) Launched February 11, 2013
TIRS bands are acquired at 100 meter resolution, but are resampled to 30 meter in delivered data product.
Putting Landsat 8’s Bands to Work
Here’s a picture of LA, just like an ordinary digital camera would take (if it had ten times as many megapixels and were in space). The image is only two weeks old, taken from Landsat 8, launched by NASA late this winter. Landsat 8 is already one of our favorite data sources – and not just ours: at State of the Map last weekend, it kept coming up in conversation with people from all kinds of backgrounds. More than just adding fresh true-color imagery from
Landsat 8 to MapBox Satellite, we’re investing in data services using the multispectral information that the satellite provides. Its non-visual bands let us analyze everything from terrain types to crop growth to natural disasters – all around the world, sometimes within hours. This post introduces some of Landsat 8’s features, to give you a feel for what the world looks like through its lens.
Landsat 8 view of the Los Angeles area, May 13th, 2013. The image is rotated so north is up. All image data courtesy of the U.S. Geological Survey.
In Landsat 8 terminology, this is a band 4-3-2 image. A band is any range of frequencies along the electromagnetic spectrum – a color, although not necessarily a color visible to the human eye. Landsat numbers its red, green, and blue sensors as 4, 3, and 2, so when we combine them we get a true-color image like this one. But have a look at the full list of Landsat 8’s bands:
Of its 11 bands, only those in the very shortest wavelengths (bands 1–4 and 8) sense visible light – all the others are in parts of the spectrum that we can’t see. The true-color view from Landsat is less than half of what it sees. To understand the value of all the bands, let’s look at them each in turn:
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