{"id":8794,"date":"2005-12-22T21:35:25","date_gmt":"2005-12-22T14:35:25","guid":{"rendered":"http:\/\/vafs.gov.vn\/vn\/2005\/12\/ung-dung-anh-vien-tham-sieu-pho-hyperspectral-vao-viec-theo-doi-qua-trinh-sa-mac-hoa-nghien-cuu-thu-nghiem-tai-tabernas-tay-ban-nha\/"},"modified":"2019-09-24T15:40:25","modified_gmt":"2019-09-24T08:40:25","slug":"ung-dung-anh-vien-tham-sieu-pho-hyperspectral-vao-viec-theo-doi-qua-trinh-sa-mac-hoa-nghien-cuu-thu-nghiem-tai-tabernas-tay-ban-nha","status":"publish","type":"post","link":"https:\/\/vafs.gov.vn\/vn\/ung-dung-anh-vien-tham-sieu-pho-hyperspectral-vao-viec-theo-doi-qua-trinh-sa-mac-hoa-nghien-cuu-thu-nghiem-tai-tabernas-tay-ban-nha\/","title":{"rendered":"\u1ee9ng d\u1ee5ng \u1ea3nh vi\u1ec5n th\u00e1m si\u00eau Ph\u1ed5 (hyperspectral) v\u00e0o vi\u1ec7c theo d\u00f5i qu\u00e1 tr\u00ecnh sa m\u1ea1c ho\u00e1. Nghi\u00ean c\u1ee9u th\u1eed nghi\u1ec7m t\u1ea1i Tabernas, T\u00e2y Ban Nha"},"content":{"rendered":"

Ho\u00e0ng Vi\u1ec7t Anh[1]<\/a><\/p>\n

Vi\u1ec7n Khoa h\u1ecdc L\u00e2m nghi\u1ec7p Vi\u1ec7t nam<\/p>\n

1. Gi\u1edbi thi\u1ec7u<\/h1>\n

Trong ba th\u1eadp k\u1ef7 qua, c\u00f4ng ngh\u1ec7 vi\u1ec5n th\u00e1m \u0111\u00e3 c\u00f3 nh\u1eefng th\u00e0nh t\u1ef1u h\u1ebft s\u1ee9c to l\u1edbn trong l\u0129nh v\u1ef1c nghi\u00ean c\u1ee9u tr\u00e1i \u0111\u1ea5t v\u00e0 tr\u1edf th\u00e0nh m\u1ed9t c\u00f4ng c\u1ee5 quan tr\u1ecdng cho vi\u1ec7c \u0111\u00e1nh gi\u00e1 v\u00e0 qu\u1ea3n l\u00fd t\u00e0i nguy\u00ean thi\u00ean nhi\u00ean. Ng\u00e0nh vi\u1ec5n th\u00e1m \u0111\u00e3 m\u1edf ra kh\u1ea3 n\u0103ng cho nh\u1eefng nghi\u00ean c\u1ee9u v\u1ec1 m\u00f4i tr\u01b0\u1eddng \u1edf m\u1ee9c to\u00e0n c\u1ea7u, cung c\u1ea5p c\u00e1c d\u1eef li\u1ec7u ch\u00ednh x\u00e1c v\u00e0 k\u1ecbp th\u1eddi cho c\u00e1c nh\u00e0 qu\u1ea3n l\u00fd.<\/p>\n

T\u1ea1i Vi\u1ec7t nam, c\u00e1c lo\u1ea1i \u1ea3nh vi\u1ec5n th\u00e1m truy\u1ec1n th\u1ed1ng nh\u01b0 LandSat, SPOT v\u00e0 \u1ea3nh m\u00e1y bay \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng kh\u00e1 r\u1ed9ng r\u00e3i trong vi\u1ec7c x\u00e2y d\u1ef1ng b\u1ea3n \u0111\u1ed3 \u0111\u1ecba h\u00ecnh, \u0111\u1ecba ch\u1ea5t, hi\u1ec7n tr\u1ea1ng r\u1eebng.Tuy nhi\u00ean nh\u1eefng lo\u1ea1i \u1ea3nh n\u00e0y c\u00f3 nh\u01b0\u1ee3c \u0111i\u1ec3m l\u00e0 s\u1ed1 b\u0103ng t\u1ea7n \u00edt (LandSat 7 b\u0103ng, SPOT 5 b\u0103ng) n\u00ean l\u01b0\u1ee3ng th\u00f4ng tin mang l\u1ea1i c\u00f2n b\u1ecb h\u1ea1n ch\u1ebf. Hi\u1ec7n \u0111\u00e3 c\u00f3 m\u1ed9t lo\u1ea1i \u1ea3nh m\u1edbi, \u1ea3nh vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 (hyperspectral), c\u00f3 h\u01a1n 100 b\u0103ng t\u1ea7n. Do s\u1ed1 b\u0103ng t\u1ea7n nhi\u1ec1u h\u01a1n, \u1ea3nh vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 (VTSP) cho ph\u00e9p gi\u1ea3i \u0111o\u00e1n nh\u1eefng y\u1ebfu t\u1ed1 h\u1ebft s\u1ee9c chi ti\u1ebft m\u00e0 tr\u00ean \u1ea3nh vi\u1ec5n th\u00e1m truy\u1ec1n th\u1ed1ng kh\u00f4ng th\u1ec3 nh\u1eadn bi\u1ebft \u0111\u01b0\u1ee3c, v\u00ed d\u1ee5 c\u00e1c lo\u1ea1i \u0111\u1ea5t, c\u00e1c kho\u00e1ng b\u1eadt, c\u00e1c lo\u1ea1i th\u1ef1c v\u1eadt kh\u00e1c nhau<\/p>\n

B\u00e0i b\u00e1o n\u00e0y nh\u1eb1m m\u1ee5c \u0111\u00edch gi\u1edbi thi\u1ec7u \u1ea3nh vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5, c\u00e1c t\u00ednh \u0111\u1eb7c \u0111i\u1ec3m k\u1ef9 thu\u1eadt c\u1ee7a lo\u1ea1i \u1ea3nh n\u00e0y v\u00e0 m\u1ed9t s\u1ed1 \u1ee9ng d\u1ee5ngc\u1ee7a n\u00f3 trong l\u0129nh v\u1ef1c nghi\u00ean c\u1ee9u m\u00f4i tr\u01b0\u1eddng. B\u00e0i b\u00e1o \u0111\u01b0\u1ee3c chia l\u00e0m 2 ph\u1ea7n: i). gi\u1edbi thi\u1ec7u c\u00e1c kh\u00e1i ni\u1ec7m c\u01a1 b\u1ea3n v\u1ec1 VTSP v\u00e0 m\u1ed9t s\u1ed1 \u1ee9ng d\u1ee5ng c\u1ee7a n\u00f3; ii). tr\u00ecnh b\u1ea7y k\u1ebft qu\u1ea3 m\u1ed9t nghi\u00ean c\u1ee9u \u1ee9ng d\u1ee5ng VTSP cho theo d\u00f5i sa m\u1ea1c ho\u00e1 \u1edf T\u00e2y Ban Nha. C\u00f4ng tr\u00ecnh n\u00e0y \u0111\u01b0\u1ee3c tr\u00edch t\u1eeb lu\u1eadn \u00e1n Th\u1ea1c s\u1ef9 c\u1ee7a t\u00e1c gi\u1ea3, th\u1ef1c hi\u1ec7n t\u1ea1i Vi\u1ec7n NC Vi\u1ec5n Th\u00e1m H\u00e0 lan (ITC), 2001.<\/p>\n

2. C\u01a1 s\u1edf vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 v\u00e0 c\u00e1c \u1ee9ng d\u1ee5ng c\u1ee7a n\u00f3 trong qu\u1ea3n l\u00fd m\u00f4i tr\u01b0\u1eddng<\/h1>\n

\u1ea3nh vi\u1ec5n th\u00e1m b\u0103ng t\u1ea7n r\u1ed9ng truy\u1ec1n th\u1ed1ng (v\u00ed d\u1ee5: \u1ea3nh LandSat 7 b\u0103ng, \u1ea3nh SPOT 5 b\u0103ng) t\u1eeb l\u00e2u \u0111\u00e3 \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng th\u00e0nh c\u00f4ng cho vi\u1ec7c x\u00e2y d\u1ef1ng b\u1ea3n \u0111\u1ed3 hi\u1ec7n tr\u1ea1ng, v\u00e0 theo d\u00f5i c\u00e1c bi\u1ebfn \u0111\u1ed5i m\u00f4i tr\u01b0\u1eddng. Tuy nhi\u00ean c\u00e1c k\u1ef9 thu\u1eadt m\u1edbi \u0111\u00e3 ch\u1ec9 ra r\u1eb1ng, b\u00ean c\u1ea1nh nh\u1eefng \u01b0u \u0111i\u1ec3m nh\u01b0 d\u1ec5 s\u1eed d\u1ee5ng, \u0111\u01b0\u1ee3c n\u1eafn ch\u1ec9nh t\u1ed1t, \u0111\u01b0\u1ee3c nhi\u1ec1u ph\u1ea7n m\u1ec1m x\u1eed l\u00fd \u1ea3nh h\u1ed7 tr\u1ee3, \u1ea3nh vi\u1ec5n th\u00e1m b\u0103ng t\u1ea7n r\u1ed9ng c\u0169ng c\u00f3 nh\u1eefng h\u1ea1n ch\u1ebf nh\u1ea5t \u0111\u1ecbnh. Do s\u1ed1 b\u0103ng t\u1ea7n \u00edt v\u00e0 \u0111\u1ed9 r\u1ed9ng c\u1ee7a m\u1ed7i b\u0103ng t\u1ea7n l\u00e0 r\u1ea5t l\u1edbn, n\u00ean tr\u00ean \u1ea3nh vi\u1ec5n th\u00e1m truy\u1ec1n th\u1ed1ng, nhi\u1ec1u th\u00f4ng tin quan tr\u1ecdng b\u1ecb tr\u1ed9n l\u1eabn v\u1edbi nhau.<\/p>\n

Tr\u00ean \u1ea3nh vi\u1ec5n th\u00e1m, gi\u00e1 tr\u1ecb quang ph\u1ed5 ph\u00e1t x\u1ea1 R (radiation value) do sensor nh\u1eadn \u0111\u01b0\u1ee3c l\u00e0 m\u1ed9t h\u00e0m s\u1ed1 (f) gi\u1eefa v\u1ecb tr\u00ed (x), th\u1eddi gian (t), \u0111\u1ed9 d\u00e0i b\u01b0\u1edbc s\u00f3ng (\u03bb), v\u00e0 g\u00f3c ch\u1ee5p (\u03b8)<\/p>\n

R=f(x,t, \u03bb, \u03b8)<\/p>\n

Qua h\u00e0m s\u1ed1 n\u00e0y ta th\u1ea5y: \u0111\u1ec3 c\u00f3 th\u00eam th\u00f4ng tin t\u1eeb \u1ea3nh, hay n\u00f3i c\u00e1ch kh\u00e1c \u0111\u1ec3 t\u0103ng \u0111\u01b0\u1ee3c gi\u00e1 tr\u1ecb R, \u00edt nh\u1ea5t m\u1ed9t trong c\u00e1c bi\u1ebfn x,t, \u03bb, \u03b8 ph\u1ea3i c\u00f3 s\u1ef1 bi\u1ebfn \u0111\u1ed5i. N\u1ebfu ch\u00fa \u00fd t\u1edbi y\u1ebfu t\u1ed1 \u0111\u1ed9 d\u00e0i b\u01b0\u1edbc s\u00f3ng ta s\u1ebd th\u1ea5y t\u1ea1i m\u1ed7i b\u01b0\u1edbc s\u00f3ng c\u00e1cv\u1eadt th\u1ec3 s\u1ebd c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 ph\u1ea3n x\u1ea1 kh\u00e1c nhau. Nhi\u1ec1u \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 ph\u1ea3n x\u1ea1 \u0111\u1eb7c tr\u01b0ng (spectral signature) gi\u00fap ch\u00fang ta ph\u00e2n bi\u1ec7t \u0111\u01b0\u1ee3c ch\u00fang v\u1edbi nh\u1eefng \u0111\u1ed1i t\u01b0\u1ee3ng kh\u00e1c, v\u00e0 ph\u1ea7n l\u1edbn nh\u1eefng \u0111i\u1ec3m \u0111\u1eb7c tr\u01b0ng n\u00e0y n\u1eb1m \u1edf nh\u1eefng b\u01b0\u1edbc s\u00f3ng r\u1ea5t h\u1eb9p. \u0110\u1ec3 \u0111o\u00e1n \u0111\u1ecdc nh\u1eefng \u0111i\u1ec3m \u0111\u1eb7c tr\u01b0ng n\u00e0y, ch\u00fang ta c\u1ea7n nh\u1eefng \u1ea3nh c\u00f3 b\u01b0\u1edbc s\u00f3ng h\u1eb9p. Vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 ra \u0111\u1eddi nh\u1eb1m ph\u1ee5c v\u1ee5 cho m\u1ee5c \u0111\u00edch n\u00f3i tr\u00ean.<\/p>\n

VTSP[2]<\/a> l\u00e0 thu\u1eadt ng\u1eef d\u00f9ng \u0111\u1ec3 ch\u1ec9 c\u00e1c h\u1ec7 th\u1ed1ng thu nh\u1eadn \u1ea3nh \u1edf r\u1ea5t nhi\u1ec1u b\u0103ng t\u1ea7n h\u1eb9p v\u00e0 li\u00ean ti\u1ebfp nhau t\u1eeb gi\u1ea3i ph\u1ed5 nh\u00ecn th\u1ea5y, c\u1eadn h\u1ed3ng ngo\u1ea1i, h\u1ed3ng ngo\u1ea1i trung, t\u1edbi h\u1ed3ng ngo\u1ea1i nhi\u1ec7t. M\u1ed9t h\u1ec7 th\u1ed1ng VTSP \u0111i\u1ec3n h\u00ecnh th\u01b0\u1eddng thu nh\u1eadn tr\u00ean 200 band d\u1eef li\u1ec7u, qua \u0111\u00f3 cho ph\u00e9p x\u00e2y d\u1ef1ng m\u1ed9t quang ph\u1ed5 ph\u1ea3n x\u1ea1[HVA1]<\/a>li\u00ean ti\u1ebfp (countinous reflectance spectrum) cho t\u1eebng \u0111i\u1ec3m \u1ea3nh (pixel). VTSP cho ph\u00e9p ph\u00e2n bi\u1ec7t <\/a>[HVA2]<\/a>\u0111\u01b0\u1ee3c c\u00e1c y\u1ebfu t\u1ed1 m\u1eb7t \u0111\u1ea5t c\u00f3 quang ph\u1ed5 chu\u1ea9n \u0111o\u00e1n n\u1eb1m trong nh\u1eefng b\u01b0\u1edbc s\u00f3ng h\u1eb9p, m\u00e0 h\u1ec7 th\u1ed1ng \u1ea3nh \u0111a ph\u1ed5 truy\u1ec1n th\u1ed1ng ko ph\u00e1t hi\u1ec7n \u0111\u01b0\u1ee3c. H\u00ecnh 1 bi\u1ec3u th\u1ecb quang ph\u1ed5 ph\u1ea3n x\u1ea1 c\u1ee7a 1 s\u1ed1 kho\u00e1ng v\u1eadt trong kho\u1ea3ng 200 t\u1edbi 250-nm. Tr\u00ean \u1ea3nh si\u00eauph\u1ed5 HyMap ta c\u00f3 th\u1ec3 th\u1ea5y m\u1ed7i kho\u00e1ng ch\u1ea5t c\u00f3 m\u1ed9t \u0111\u01b0\u1eddng quang ph\u1ed5 kh\u00e1c bi\u1ec7t v\u1edbi c\u00e1c \u0111\u1ec9nh h\u1ea5p th\u1ee5 v\u00e0 ph\u1ea3n x\u1ea1 t\u1ea1i nh\u1eefng b\u01b0\u1edbc s\u00f3ng nh\u1ea5t \u0111\u1ecbnh. Trong khi \u0111\u00f3 band 7 \u1ea3nh Landsat TM \u1edf kho\u1ea3ng s\u00f3ng n\u00e0y ch\u1ec9 cho ta 1 \u0111i\u1ec3m d\u1eef li\u1ec7u duy nh\u1ea5t do \u0111\u00f3 kh\u00f4ng th\u1ec3 ph\u00e2n bi\u1ec7t \u0111\u01b0\u1ee3c c\u00e1c kho\u00e1ng v\u1eadt n\u00e0y.<\/p>\n

H\u00ecnh 1. Quang ph\u1ed5 ph\u1ea3n x\u1ea1 c\u1ee7a m\u1ed9t s\u1ed1 kho\u00e1ng v\u1eadt tr\u00ean \u1ea3nh HyMap<\/p>\n

Thi\u1ebft b\u1ecb VTSP \u0111\u1ea7u ti\u00ean l\u00e0 Fluorescence Line Image (FLI), v\u00e0 Airborne Imaging Spectrometer (AIS) do NASA ch\u1ebf t\u1ea1o n\u0103m 1981 v\u00e0 1983. Thi\u1ebft b\u1ecb n\u00e0y thu th\u1eadp 128 band d\u1eef li\u1ec7u trong kho\u1ea3ng 1200 \u0111\u1ebfn 2400 nm, \u0111\u1ed9 r\u1ed9ng c\u1ee7a m\u1ed7i b\u0103ng l\u00e0 9.3 nm. N\u0103m 1987 NASA \u0111\u00e3 c\u1ea3i ti\u1ebfn h\u1ec7 th\u1ed1ng AIS th\u00e0nh h\u1ec7 th\u1ed1ng Airborne Visible\/Infrared Imaging Spectrometer (AVIRIS). AVIRIS \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf v\u1edbi c\u00e1c ch\u1ee9c n\u0103ng n\u1eafn ch\u1ec9nh ti\u00ean ti\u1ebfn \u0111\u1ec3 ph\u1ee5c v\u1ee5 cho c\u00e1c nghi\u00ean c\u1ee9u \u0111a ng\u00e0nh. Hi\u1ec7n nay VTSP \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng trong m\u1ed9t s\u1ed1 nghi\u00ean c\u1ee9u v\u1ec1: kho\u00e1ng v\u1eadt b\u1ec1 m\u1eb7t, ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc, \u0111o \u0111\u1ed9 s\u00e2u, x\u00e1c \u0111\u1ecbnh x\u00f3i m\u00f2n \u0111\u1ea5t, x\u00e1c \u0111\u1ecbnh lo\u1ea1i th\u1ef1c v\u1eadt, h\u00e0m l\u01b0\u1ee3ng n\u01b0\u1edbc trong l\u00e1 …vv. Nhi\u1ec1u t\u1ed5 ch\u1ee9c vi\u1ec5n th\u00e1m v\u00e0 c\u00e1c c\u00f4ng ty t\u01b0 nh\u00e2n \u0111\u00e3 s\u1ea3n xu\u1ea5t nhi\u1ec1u lo\u1ea1i thi\u1ebft b\u1ecb VTSP kh\u00e1c nhau, danh s\u00e1ch v\u00e0 \u0111\u1eb7c t\u00ednh k\u1ef9 thu\u1eadt chi ti\u1ebft c\u1ee7a c\u00e1c h\u1ec7 th\u1ed1ng VTSP hi\u1ec7n h\u00e0nh c\u00f3 th\u1ec3 tham kh\u1ea3o Van de Meer, 1999<\/p>\n

3. \u1ee9ng d\u1ee5ng VTSP v\u00e0o vi\u1ec7c theo d\u00f5i qu\u00e1 tr\u00ecnh sa m\u1ea1c ho\u00e1<\/h1>\n

T\u00e2y Ban Nha l\u00e0 qu\u1ed1c gia duy nh\u1ea5t \u1edf ch\u00e2u \u00c2u ch\u1ecbu \u1ea3nh h\u01b0\u1edfng c\u1ee7a sa m\u1ea1c ho\u00e1 t\u1edbi h\u01a1n m\u1ed9t n\u1eeda di\u1ec7n t\u00edch \u0111\u1ea5t n\u00f4ng nghi\u1ec7p. \u0110i\u1ec1u ki\u1ec7n m\u00f4i tr\u01b0\u1eddng kh\u1eafc nghi\u1ec7t v\u1edbi 10 th\u00e1ng m\u00f9a kh\u00f4, m\u00f9a m\u01b0a ng\u1eafn v\u1edbi l\u0169 l\u1edbn, \u0111\u1ecba h\u00ecnh chia c\u1eaft m\u1ea1nh, v\u00e0 t\u1ea7ng \u0111\u1ea5t m\u1ecfng l\u00e0m cho qu\u00e1 tr\u00ecnh x\u00f3i m\u00f2n x\u1ea9y ra h\u1ebft s\u1ee9c m\u1ea1nh m\u1ebd. V\u00f9ng Tebernas thu\u1ed9c t\u1ec9nh Almeria l\u00e0 v\u00f9ng b\u1ecb sa m\u1ea1c ho\u00e1 nghi\u00eam tr\u1ecdng nh\u1ea5t mi\u1ec1n \u0110\u00f4ng Nam T\u00e2y Ban Nha. Vi\u1ec7c x\u00e1c \u0111\u1ecbnh v\u00e0 ki\u1ec3m so\u00e1t qu\u00e1 tr\u00ecnh n\u00e0y l\u00e0 h\u1ebft s\u1ee9c c\u1ea7n thi\u1ebft kh\u00f4ng nh\u1eefng cho T\u00e2y Ban Nha m\u00e0 cho c\u1ea3 nh\u1eefng qu\u1ed1c gia kh\u00e1c \u0111ang ph\u1ea3i \u0111\u1ed1i \u0111\u1ea7u v\u1edbi v\u1ea5n \u0111\u1ec1 sa m\u1ea1c ho\u00e1. Tuy nhi\u00ean c\u00e1c lo\u1ea1i \u1ea3nh vi\u1ec5n th\u00e1m truy\u1ec1n th\u1ed1ng nh\u01b0 LandSat, SPOT l\u1ea1i kh\u00f4ng \u0111\u1ee7 \u0111\u1ed9 ph\u00e2n gi\u1ea3i \u0111\u1ec3 \u0111o\u00e1n \u0111\u1ecdc c\u00e1c lo\u1ea1i hi\u1ec7n tr\u1ea1ng sa m\u1ea1c ho\u00e1 nh\u01b0, \u0111\u1ea5t x\u00f3i m\u00f3n tr\u01a1 s\u1ecfi \u0111\u00e1, \u0111\u1ea5t b\u1ecb nhi\u1ec5m m\u1eb7n …vv. M\u1ee5c ti\u00eau nghi\u00ean c\u1ee9u c\u1ee7a \u0111\u1ec1 t\u00e0i \u0111\u1eb7t ra l\u00e0 \u1ee9ng d\u1ee5ng k\u1ef9 thu\u1eadt VTSP \u0111\u1ec3 theo d\u00f5i qu\u00e1 tr\u00ecnh n\u00e0y.<\/p>\n

V\u00f9ng nghi\u00ean c\u1ee9u, d\u1eef li\u1ec7u v\u00e0 ph\u01b0\u01a1ng ph\u00e1p<\/i><\/h2>\n

Thung l\u0169ng Tabernas n\u1eb1m \u1edf ph\u00eda \u0110\u00f4ng nam T\u00e2y Ban Nha, v\u1edbi kh\u00ed h\u1eadu n\u00f3ng v\u00e0 kh\u00f4 \u0111i\u1ec3n h\u00ecnh c\u1ee7a v\u00f9ng \u0110\u1ecba Trung H\u1ea3i. L\u01b0\u1ee3ng m\u01b0a h\u00e0ng n\u0103m r\u1ea5t th\u1ea5p (220-mm\/n\u0103m), v\u00e0 c\u00e1c tr\u1eadn m\u01b0a th\u01b0\u1eddng t\u1eadp trung trong v\u00f2ng 30 ng\u00e0y c\u1ee7a th\u00e1ng 11 t\u1ea1o ra c\u00e1c tr\u1eadn l\u0169 l\u1edbn. Do m\u1eb7t \u0111\u1ea5t h\u1ea7u nh\u01b0 kh\u00f4ng c\u00f3 th\u1ef1c v\u1eadt che ph\u1ee7 n\u00ean qu\u00e1 tr\u00ecnh x\u00f3i m\u00f2n x\u1ea9y ra m\u1ea1nh. T\u1ea5t c\u1ea3 c\u00e1c \u0111i\u1ec1u ki\u1ec7n tr\u00ean c\u1ed9ng v\u1edbi kh\u00ed h\u1eadu kh\u00f4 n\u00f3ng v\u00e0 \u0111i\u1ec1u ki\u1ec7n \u0111\u1ecba ch\u1ea5t \u0111\u1eb7c bi\u1ec7t \u0111\u00e3 \u0111\u1ea9y nhanh qu\u00e1 tr\u00ecnh sa m\u1ea1c h\u00f3a v\u00e0 t\u1ea1o ra b\u1ed1n lo\u1ea1i \u0111\u1ea5t sau: \u0111\u1ea5t nhi\u1ec5m m\u1eb7n, \u0111\u1ea5t x\u00f3i m\u00f2n tr\u01a1 s\u1ecfi \u0111\u00e1, \u0111\u1ea5t c\u00f3 h\u00e0m l\u01b0\u1ee3ng calci cao, v\u00e0 \u0111\u1ea5t c\u00f3 h\u00e0m l\u01b0\u1ee3ng th\u1ea1ch cao cao.<\/p>\n

D\u1eef li\u1ec7u vi\u1ec5n th\u00e1m s\u1eed d\u1ee5ng cho nghi\u00ean c\u1ee9u n\u00e0y l\u00e0 \u1ea3nh HyMap ch\u1ee5p th\u00e1ng 7\/1999. \u1ea3nh HyMap thu th\u1eadp d\u1eef li\u1ec7u trong kho\u1ea3ng b\u01b0\u1edbc s\u00f3ng 400-2500-nm, chia l\u00e0m 128 band v\u1edbi \u0111\u1ed9 r\u1ed9ng c\u1ee7a m\u1ed7i band l\u00e0 16-nm. \u0110\u1ed9 ph\u00e2n gi\u1ea3i m\u1eb7t \u0111\u1ea5t (pixel size) l\u00e0 7\u00b47-m.<\/p>\n

Do \u1ea3nh VTSP c\u00f3 s\u1ed1 band d\u1eef li\u1ec7u r\u1ea5t l\u1edbn n\u00ean c\u00e1c ph\u01b0\u01a1ng ph\u00e1p ph\u00e2n lo\u1ea1i \u1ea3nh truy\u1ec1n th\u1ed1ng nh\u01b0 Nearest Neighbourhood ho\u1eb7c Maximumlikelyhood kh\u00f4ng ph\u00f9 h\u1ee3p v\u00ec s\u1ebd t\u1ed1n r\u1ea5t nhi\u1ec1u th\u1eddi gian t\u00ednh to\u00e1n. Ph\u01b0\u01a1ng ph\u00e1p \u00e1p d\u1ee5ng cho nghi\u00ean c\u1ee9u n\u00e0y l\u00e0 Linear Spectral Unmixing (LSU). \u0110\u00e2y l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p m\u1edbi \u0111ang \u0111\u01b0\u1ee3c th\u1eed nghi\u1ec7m trong l\u0129nh v\u1ef1c ph\u00e2n lo\u1ea1i \u1ea3nh vi\u1ec5n th\u00e1m. Nguy\u00ean l\u00fd c\u1ee7a ph\u01b0\u01a1ng ph\u00e1p n\u00e0y c\u00f3 th\u1ec3 m\u00f4 t\u1ea3 t\u00f3m t\u1eaft nh\u01b0 sau:<\/p>\n

-Ng\u01b0\u1eddi ta th\u1ea5y r\u1eb1ng trong di\u1ec7n t\u00edch c\u1ee7a 1 pixel th\u01b0\u1eddng c\u00f3 nhi\u1ec1u y\u1ebfu t\u1ed1 kh\u00e1c nhau: v\u00ed d\u1ee5 30% l\u00e0 n\u01b0\u1edbc, 30% l\u00e0 l\u00faa, 40% l\u00e0 \u0111\u1ea5t tr\u1ed1ng. M\u1ed7i y\u1ebfu t\u1ed1 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 1 endmember.<\/p>\n

-Quang ph\u1ed5 ph\u1ea3n x\u1ea1 c\u1ee7a m\u1ed7i m\u1ed9t pixel tr\u00ean \u1ea3nh l\u00e0 trung b\u00ecnh c\u1ed9ng quang ph\u1ed5 c\u1ee7a t\u1eebng endmember nh\u00e2n v\u1edbi tr\u1ecdng s\u1ed1 l\u00e0 % di\u1ec7n t\u00edch c\u1ee7a endmember \u0111\u00f3 (xem h\u00ecnh 2)<\/p>\n

-V\u00ec v\u1eady khi bi\u1ebft gi\u00e1 tr\u1ecb quang ph\u1ed5 c\u1ee7a 1 pixel v\u00e0 bi\u1ebft \u0111\u01b0\u1ee3c gi\u00e1 tr\u1ecb quang ph\u1ed5 c\u1ee7a c\u00e1c endmember, ta c\u00f3 th\u1ec3 t\u00ednh \u0111\u01b0\u1ee3c di\u1ec7n t\u00edch c\u1ee7a t\u1eebng endmember th\u00f4ng qua thu\u1eadt to\u00e1n h\u1ed3i quy.<\/p>\n

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H\u00ecnh 2. Linear Spectral Unmixing cho 1 pixel (ngu\u1ed3n: Boardman 1993)<\/p>\n

Trong nghi\u00ean c\u1ee9u n\u00e0y, quang ph\u1ed5 c\u1ee7a c\u00e1c endmember \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh b\u1eb1ng c\u00e1ch: i). \u0111o tr\u1ef1c ti\u1ebfp tr\u00ean th\u1ef1c \u0111\u1ecba; ii). sau \u0111\u00f3 ti\u1ebfn h\u00e0nh n\u1eafn ch\u1ec9nh (calibration) d\u1ef1a tr\u00ean d\u1eef li\u1ec7u \u1ea3nh.Ph\u1ea7n m\u1ec1m s\u1eed d\u1ee5ng cho ph\u00e2n lo\u1ea1i \u1ea3nh l\u00e0 Envi 3.0. K\u1ebft qu\u1ea3 ph\u00e2n lo\u1ea1i \u1ea3nh HyMap \u0111\u01b0\u1ee3c tr\u00ecnh b\u1ea7y \u1edf h\u00ecnh 3.<\/p>\n

H\u00ecnh 3. \u1ea3nh ph\u00e2n lo\u1ea1i c\u00e1c y\u1ebfu t\u1ed1 sa m\u1ea1c ho\u00e1.<\/p>\n

K\u1ebft qu\u1ea3 v\u00e0 th\u1ea3o lu\u1eadn<\/i><\/h2>\n

\u0110\u1ed9 ch\u00ednh x\u00e1c c\u1ee7a \u1ea3nh ph\u00e2n lo\u1ea1i \u0111\u01b0\u1ee3c ki\u1ec3m tra b\u1eb1ng 200 \u0111i\u1ec3m \u0111\u1ed1i ch\u1ee9ng tr\u00ean th\u1ef1c \u0111\u1ecba. K\u1ebft qu\u1ea3 cho th\u1ea5y Gypsifereous soil (\u0111\u1ea5t ch\u1ee9a th\u1ea1ch cao) \u0111\u1ea1t \u0111\u1ed9 ch\u00ednh x\u00e1c 93%, Saline soil (\u0111\u1ea5t nhi\u1ec5m m\u1eb7n): 75%, Calcareous soil (\u0111\u1ea5t ch\u1ee9a Calxi): 70%, Desert pavement (x\u00f3i m\u00f2n tr\u01a1 s\u1ecfi \u0111\u00e1) 60%, Shrub in hilland (c\u00e2y b\u1ee5i): 60%. \u0110\u1ed9 ch\u00ednh x\u00e1c chung \u0111\u1ea1t 71%.<\/p>\n

So v\u1edbi c\u00e1c ti\u00eau chu\u1ea9n ph\u00e2n lo\u1ea1i \u1ea3nh th\u00f4ng th\u01b0\u1eddng, th\u01b0\u1eddng l\u00e0 80%, \u0111\u1ed9 ch\u00ednh x\u00e1c n\u00e0y ch\u01b0a ph\u1ea3i l\u00e0 cao. Tuy nhi\u00ean c\u1ea7n ch\u00fa \u00fd r\u1eb1ng, 80% l\u00e0 ti\u00eau chu\u1ea9n \u0111\u1eb7t ra cho vi\u1ec7c ph\u00e2n lo\u1ea1i b\u1ea3n \u0111\u1ed3 hi\u1ec7n tr\u1ea1ng, v\u1edbi c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng kh\u00e1c nhau r\u1ea5t r\u00f5 r\u1ec7t, v\u00ed d\u1ee5 gi\u1eefa m\u1eb7t n\u01b0\u1edbc v\u00e0 \u0111\u01b0\u1eddng x\u00e1, gi\u1eefa \u0111\u1ea5t tr\u1ed1ng v\u00e0 \u0111\u1ea5t c\u00f3 r\u1eebng …vv -trong khi c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng trong nghi\u00ean c\u1ee9u n\u00e0y \u0111\u1ec1u l\u00e0 \u0111\u1ea5t tr\u1ed1ng, h\u1ea7u nh\u01b0 kh\u00f4ng th\u1ec3 ph\u00e2n bi\u1ec7t \u0111\u01b0\u1ee3c tr\u00ean \u1ea3nh h\u00e0ng kh\u00f4ng v\u00e0 \u1ea3nh LandSat. Nh\u00ecn t\u1eeb g\u00f3c \u0111\u1ed9 n\u00e0y th\u00ec \u0111\u1ed9 ch\u00ednh x\u00e1c 71% tr\u00ean \u1ea3nh Hyperspectral l\u00e0 cao v\u00e0 r\u1ea5t c\u00f3 \u00fd ngh\u0129a.<\/p>\n

Trong nh\u1eefng n\u0103m t\u1edbi, \u1ea3nh VTSP v\u1edbi c\u00e1c \u01b0u \u0111i\u1ec3m c\u1ee7a m\u00ecnh ch\u1eafc ch\u1eafn s\u1ebd tr\u1edf th\u00e0nh m\u1ed9t xu th\u1ebf m\u1edbi c\u1ee7a \u0111i\u1ec1u tra vi\u1ec5n th\u00e1m. T\u1ea1i Vi\u1ec7t nam, VTSPc\u00f3 th\u1ec3 \u1ee9ng d\u1ee5ng cho nh\u1eefng l\u0129nh v\u1ef1c sau: x\u00e2y d\u1ef1ng b\u1ea3n \u0111\u1ed3 m\u1eb7n ho\u00e1 v\u00f9ng ven bi\u1ec3n, sa m\u1ea1c ho\u00e1 v\u00f9ng ven bi\u1ec3n mi\u1ec1n Trung, ph\u00e2n lo\u1ea1i th\u1ea3m th\u1ef1c v\u1eadt, \u0111o \u0111\u1ed9 kh\u00f4 c\u1ee7a t\u00e1n r\u1eebng ph\u1ee5c v\u1ee5 d\u1ef1 b\u00e1o ch\u00e1y r\u1eebng, \u0111\u00e1nh gi\u00e1 ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc. Ch\u00fang ta c\u1ea7n x\u00fac ti\u1ebfn nghi\u00ean c\u1ee9u VTSP \u0111\u1ec3 b\u1eaft k\u1ecbp c\u00e1c ti\u1ebfn b\u1ed9 v\u1ec1 k\u1ef9 thu\u1eadt n\u00e0y khi \u1ea3nh vi\u1ec5n th\u00e1m Hyperspectral \u0111\u01b0\u1ee3c th\u01b0\u01a1ng m\u1ea1i ho\u00e1 v\u00e0o n\u0103m 2004-2005.<\/p>\n

Summary<\/b><\/p>\n

Hyperspectral sensing and its application for desertification monitoring \u2014 Case study in Tabernas, Spain<\/p>\n

Many studies showed that conventional Remote sensing image such as SPOT and Landsat can be use to map land use\/land cover as well as to predict salinity level, nutrient status of the soil. However, those conventional image with a few spectral bands may over smooth the reflectance characteristic of the surface. Hyperspectral remote sensing is a promising data source to over come this problem .A general introduction of hyperspectral remote sensing , its principle, characteristic, typical sensor, and application has been presented. Case study on desertification monitoring in Terbernas, Spain, showed that hyperspectral image can be used to map desertification feature with the accuracy of 71%.<\/p>\n

T\u00e0i li\u1ec7u tham kh\u1ea3o<\/h1>\n

1.Boardman J.W (1993). Automated spectral unmixing AVIRIS data using convex geometry concepts. Fourth JPL Airborn Geosience Workshop, JPL publication.<\/p>\n

2.Coleman, T.L. (1993). Spectral differntiation of surface soil and soil properties: Is it possible from space platfroms?. Soil science 155 (4) 283-293<\/p>\n

3.Rao. UR. (1993). Space and environment, 44th congress of the International Astronautical federation, 1993, Graz, Austria<\/p>\n

4.ENV 3.2 (1999). The Environment for Visualizing Images: User’s Guide. Colorado, Limited Liability Company.<\/p>\n

5.Van Der Meer (1999). Camera and Multispectral scanning system in Remote sensing as apply for geology. ITC lecture note, No RSD 10<\/p>\n

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[1]<\/a> Trung t\u00e2m nghi\u00ean c\u1ee9u Sinh th\u00e1i v\u00e0 M\u00f4i tr\u01b0\u1eddng r\u1eebng \u2014 Vi\u1ec7n Khoa h\u1ecdc l\u00e2m nghi\u1ec7p Vi\u1ec7t nam<\/p>\n<\/div>\n

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[2]<\/a> Hyperspectral sensing l\u00e0 m\u1ed9t k\u1ef9 thu\u1eadt t\u01b0\u01a1ng \u0111\u1ed1i m\u1edbi, do ch\u01b0a t\u00ecm th\u1ea5y thu\u1eadt ng\u1eef t\u01b0\u01a1ng \u0111\u01b0\u01a1ng trong c\u00e1c t\u00e0i li\u1ec7u v\u1ec1 vi\u1ec5n th\u00e1m \u1edf Vi\u1ec7t nam n\u00ean ch\u00fang t\u00f4i t\u1ea1m d\u1ecbch l\u00e0 vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 \u0111\u1ec3 c\u00f3 s\u1ef1 li\u00ean h\u1ec7 t\u01b0\u01a1ng \u0111\u1ed1i v\u1edbi thu\u1eadt ng\u1eef vi\u1ec5n th\u00e1m \u0111a ph\u1ed5 (multispectral)<\/p>\n<\/div>\n<\/div>\n

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Other word??<\/p>\n<\/div>\n<\/div>\n

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Gi\u1ea3i \u0111o\u00e1n<\/p>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

1. Gi\u1edbi thi\u1ec7u
\nTrong ba th\u1eadp k\u1ef7 qua, c\u00f4ng ngh\u1ec7 vi\u1ec5n th\u00e1m \u0111\u00e3 c\u00f3 nh\u1eefng th\u00e0nh t\u1ef1u h\u1ebft s\u1ee9c to l\u1edbn trong l\u0129nh v\u1ef1c nghi\u00ean c\u1ee9u tr\u00e1i \u0111\u1ea5t v\u00e0 tr\u1edf th\u00e0nh m\u1ed9t c\u00f4ng c\u1ee5 quan tr\u1ecdng cho vi\u1ec7c \u0111\u00e1nh gi\u00e1 v\u00e0 qu\u1ea3n l\u00fd t\u00e0i nguy\u00ean thi\u00ean nhi\u00ean. Ng\u00e0nh vi\u1ec5n th\u00e1m \u0111\u00e3 m\u1edf ra kh\u1ea3 n\u0103ng cho nh\u1eefng nghi\u00ean c\u1ee9u v\u1ec1 m\u00f4i tr\u01b0\u1eddng \u1edf m\u1ee9c to\u00e0n c\u1ea7u, cung c\u1ea5p c\u00e1c d\u1eef li\u1ec7u ch\u00ednh x\u00e1c v\u00e0 k\u1ecbp th\u1eddi cho c\u00e1c nh\u00e0 qu\u1ea3n l\u00fd.
\nT\u1ea1i Vi\u1ec7t nam, c\u00e1c lo\u1ea1i \u1ea3nh vi\u1ec5n th\u00e1m truy\u1ec1n th\u1ed1ng nh\u01b0 LandSat, SPOT v\u00e0 \u1ea3nh m\u00e1y bay \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng kh\u00e1 r\u1ed9ng r\u00e3i trong vi\u1ec7c x\u00e2y d\u1ef1ng b\u1ea3n \u0111\u1ed3 \u0111\u1ecba h\u00ecnh, \u0111\u1ecba ch\u1ea5t, hi\u1ec7n tr\u1ea1ng r\u1eebng. Tuy nhi\u00ean nh\u1eefng lo\u1ea1i \u1ea3nh n\u00e0y c\u00f3 nh\u01b0\u1ee3c \u0111i\u1ec3m l\u00e0 s\u1ed1 b\u0103ng t\u1ea7n \u00edt (LandSat 7 b\u0103ng, SPOT 5 b\u0103ng) n\u00ean l\u01b0\u1ee3ng th\u00f4ng tin mang l\u1ea1i c\u00f2n b\u1ecb h\u1ea1n ch\u1ebf. Hi\u1ec7n \u0111\u00e3 c\u00f3 m\u1ed9t lo\u1ea1i \u1ea3nh m\u1edbi, \u1ea3nh vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 (hyperspectral), c\u00f3 h\u01a1n 100 b\u0103ng t\u1ea7n. Do s\u1ed1 b\u0103ng t\u1ea7n nhi\u1ec1u h\u01a1n, \u1ea3nh vi\u1ec5n th\u00e1m si\u00eau ph\u1ed5 (VTSP) cho ph\u00e9p gi\u1ea3i \u0111o\u00e1n nh\u1eefng y\u1ebfu t\u1ed1 h\u1ebft s\u1ee9c chi ti\u1ebft m\u00e0 tr\u00ean \u1ea3nh vi\u1ec5n th\u00e1m truy\u1ec1n th\u1ed1ng kh\u00f4ng th\u1ec3 nh\u1eadn bi\u1ebft \u0111\u01b0\u1ee3c, v\u00ed d\u1ee5 c\u00e1c lo\u1ea1i \u0111\u1ea5t, c\u00e1c kho\u00e1ng b\u1eadt, c\u00e1c lo\u1ea1i th\u1ef1c v\u1eadt kh\u00e1c nhau<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[21],"tags":[],"_links":{"self":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8794"}],"collection":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/comments?post=8794"}],"version-history":[{"count":2,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8794\/revisions"}],"predecessor-version":[{"id":19180,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8794\/revisions\/19180"}],"wp:attachment":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/media?parent=8794"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/categories?post=8794"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/tags?post=8794"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}