H\u1ec7 \u0111\u1ebfm th\u01b0\u1eddng d\u00f9ng l\u00e0 h\u1ec7 \u0111\u1ebfm c\u01a1 s\u1ed1 10, n\u1ebfu 10x = y th\u00ec ta c\u00f3 log10y = x, th\u1ebf nh\u01b0ng trong l\u00ed thuy\u1ebft th\u00f4ng tin, c\u00e1c lo\u1ea1i m\u00e1y t\u00ednh l\u1edbn nh\u1ecf \u0111\u1ec1u d\u00f9ng c\u00e1c s\u1ed1 \u1edf h\u1ec7 \u0111\u1ebfm c\u01a1 s\u1ed1 hai. \u1edf Trung Qu\u1ed1c th\u1eddi c\u1ed5 \u0111\u1ea1i, ng\u01b0\u1eddi ta \u0111\u00e3 d\u00f9ng \u0111\u00e0i l\u1eeda (phong ho\u1ea3 \u0111\u00e0i) \u0111\u1ec3 l\u00e0m c\u00f4ng c\u1ee5 truy\u1ec1n tin. Khi \u0111\u1ed1t l\u1eeda \u1edf phong ho\u1ea3 \u0111\u00e0i l\u00e0 b\u00e1o hi\u1ec7u c\u00f3 k\u1ebb \u0111\u1ecbch x\u00e2m ph\u1ea1m. N\u1ebfu kh\u00f4ng c\u00f3 kh\u00f3i l\u1eeda l\u00e0 \u0111\u1ecbch ch\u01b0a \u0111\u1ebfn. \u0110\u00e0i l\u1eeda ch\u1ec9 truy\u1ec1n \u0111i hai lo\u1ea1i t\u00ecnh hu\u1ed1ng \u201cc\u00f3\u201d ho\u1eb7c \u201ckh\u00f4ng c\u00f3\u201d. \u0110\u00f3 l\u00e0 c\u00e1ch th\u00f4ng tin \u0111\u01a1n gi\u1ea3n ng\u01b0\u1eddi ta l\u1ea5y \u0111\u00f3 l\u00e0m \u0111\u01a1n v\u1ecb truy\u1ec1n tin v\u00e0 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 \u201c1 bit\u201d. N\u1ebfu d\u00f9ng ch\u1eef s\u1ed1 \u0111\u1ec3 m\u00f4 t\u1ea3 ta c\u00f3 th\u1ec3 vi\u1ebft 0 (l\u00e0 kh\u00f4ng c\u00f3 kh\u00f3i) v\u00e0 1 (c\u00f3 kh\u00f3i) l\u00e0 ch\u1ec9 hai t\u00ecnh hu\u1ed1ng th\u00f4ng tin, theo \u0111\u1ecbnh ngh\u0129a c\u00f4ng ngh\u1ec7 th\u00f4ng tin log22 = 1.<\/p>\n\n\n\n
Gi\u1ea3 thi\u1ebft \u0111\u00e0i kh\u00f3i c\u00f3 hai \u1ed1ng kh\u00f3i: \u1ed1ng A \u0111\u1ec3 ch\u1ec9 t\u00ecnh h\u00ecnh \u0111\u1ecbch: c\u00f3 k\u1ebb \u0111\u1ecbch x\u00e2m ph\u1ea1m (1) ho\u1eb7c k\u1ebb \u0111\u1ecbch ch\u01b0a x\u00e2m ph\u1ea1m (0); \u1ed1ng B \u0111\u1ec3 ch\u1ec9 t\u00ecnh h\u00ecnh ta: (1) c\u1ea7n t\u0103ng c\u01b0\u1eddng b\u1ed1 ph\u00f2ng, (0) ch\u01b0a c\u1ea7n t\u0103ng c\u01b0\u1eddng b\u1ed1 ph\u00f2ng. Theo \u0111\u00f3 ta c\u00f3 b\u1ed1n lo\u1ea1i t\u00ecnh hu\u1ed1ng:<\/p>\n\n\n\n
Nh\u01b0 v\u1eady ch\u00fang ta \u0111\u00e3 thu nh\u1eadn \u0111\u01b0\u1ee3c l\u01b0\u1ee3ng th\u00f4ng tin l\u1edbn h\u01a1n, h\u00e0m l\u01b0\u1ee3ng th\u00f4ng tin l\u00e0 log24 = 2 bit.<\/p>\n\n\n\n
Ch\u00fang ta c\u0169ng d\u1ec5 t\u01b0\u1edfng t\u01b0\u1ee3ng th\u1ea5y n\u1ebfu \u0111\u00e0i c\u00f3 ba \u1ed1ng kh\u00f3i th\u00ec ta c\u00f3 th\u1ec3 truy\u1ec1n \u0111i 8 t\u00ecnh hu\u1ed1ng th\u00f4ng tin (0, 0, 0); (0, 0, 1); (0, 1, 0); (0, 1, 1); (1, 0, 0); (1, 0, 1); (1, 1, 0); (1, 1, 1) v\u00e0 h\u00e0m l\u01b0\u1ee3ng th\u00f4ng tin l\u00e0 log28 = 3 bit.<\/p>\n\n\n\n
C\u00e1c t\u00ecnh hu\u1ed1ng th\u00f4ng tin ph\u1ee9c t\u1ea1p kh\u00e1c \u0111\u1ec1u c\u00f3 th\u1ec3 ch\u1ebf bi\u1ebfn t\u1eeb c\u00e1ch truy\u1ec1n tin \u0111\u01a1n gi\u1ea3n nh\u01b0 tr\u00ean. Ch\u00ednh v\u00ec vi\u1ec7c truy\u1ec1n tin ch\u1ee7 y\u1ebfu ch\u1ec9 c\u00f3 hai kh\u1ea3 n\u0103ng n\u00ean c\u00e1c m\u00e1y t\u00ednh thu nh\u1eadn th\u00f4ng tin tr\u00ean c\u00e1c s\u1ed1 theo h\u1ec7 \u0111\u1ebfm c\u01a1 s\u1ed1 hai v\u00e0 thu \u0111\u01b0\u1ee3c l\u01b0\u1ee3ng th\u00f4ng tin c\u01a1 s\u1edf l\u00e0 1. V\u00e0 n\u1ebfu khi thu nh\u1eadn th\u00f4ng tin y = 2x th\u00ec khi bi\u1ebfn \u0111\u1ed5i s\u1ebd d\u00f9ng log2 y = x m\u00e1y t\u00ednh s\u1ebd ph\u1ea3n \u00e1nh ch\u00ednh x\u00e1c l\u01b0\u1ee3ng th\u00f4ng tin th\u1ef1c.<\/p>\n\n\n\n
T\u1eeb kho\u00e1: L\u01b0\u1ee3ng th\u00f4ng tin.<\/p>\n\n\n\n
<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"
H\u1ec7 \u0111\u1ebfm th\u01b0\u1eddng d\u00f9ng l\u00e0 h\u1ec7 \u0111\u1ebfm c\u01a1 s\u1ed1 10, n\u1ebfu 10x = y th\u00ec ta c\u00f3 log10y = x, th\u1ebf nh\u01b0ng trong l\u00ed thuy\u1ebft th\u00f4ng tin, c\u00e1c lo\u1ea1i m\u00e1y t\u00ednh l\u1edbn nh\u1ecf \u0111\u1ec1u d\u00f9ng c\u00e1c s\u1ed1 \u1edf h\u1ec7 \u0111\u1ebfm c\u01a1 s\u1ed1 hai. \u1edf Trung Qu\u1ed1c th\u1eddi c\u1ed5 \u0111\u1ea1i, ng\u01b0\u1eddi ta \u0111\u00e3 d\u00f9ng \u0111\u00e0i l\u1eeda […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15,9],"tags":[],"class_list":["post-7535","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-toan-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7535","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=7535"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7535\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=7535"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=7535"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=7535"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}