{"id":2189,"date":"2024-02-21T09:59:20","date_gmt":"2024-02-21T01:59:20","guid":{"rendered":"https:\/\/usei.cn\/?p=2189"},"modified":"2024-03-11T16:36:37","modified_gmt":"2024-03-11T08:36:37","slug":"lstm-long-short-term-memory-%e9%95%bf%e7%9f%ad%e6%9c%9f%e8%ae%b0%e5%bf%86%e7%bd%91%e7%bb%9c","status":"publish","type":"post","link":"https:\/\/usei.cn\/index.php\/2024\/02\/21\/lstm-long-short-term-memory-%e9%95%bf%e7%9f%ad%e6%9c%9f%e8%ae%b0%e5%bf%86%e7%bd%91%e7%bb%9c\/","title":{"rendered":"LSTM (Long Short-Term Memory) \u957f\u77ed\u671f\u8bb0\u5fc6\u7f51\u7edc"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">1.\u7f51\u7edc\u795e\u7ecf\u5143\u7ed3\u6784<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-15.png\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-15-1024x395.png'><img class=\"lazyload lazyload-style-3\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"395\" data-original=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-15-1024x395.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2252\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/a><\/figure>\n\n\n\n<p>$$NDVI=\\frac{NIR\u8fd1\u7ea2\u5916-RED\u7ea2\u8272}{NIR\u8fd1\u7ea2\u5916+RED\u7ea2\u8272}$$<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9057\u5fd8\u95e8 (forget gate)\uff1a$f_t=\\sigma(W_f\\cdot[x_t,h_{t-1}]+b_f)$ \u8868\u793a\u5bf9\u4fe1\u606f\u7684<strong>\u8bb0\u5fc6\u7a0b\u5ea6<\/strong>\uff1b<\/li>\n\n\n\n<li>\u8f93\u5165\u95e8 (input gate)\uff1a$i_t=\\sigma(W_i\\cdot[x_t,h_{t-1}]+b_i)$ \uff0c\u8868\u793a\u5bf9\u4fe1\u606f\u7684<strong>\u8f93\u5165\u5f3a\u5ea6<\/strong>\uff1b<\/li>\n\n\n\n<li>\u72b6\u6001\u95e8 (cell gate)\uff1a$g_t=tanh(W_g\\cdot[x_t,h_{t-1}]+b_g)$ \uff0c\u8868\u793a\u5bf9\u8f93\u5165\u4fe1\u606f\u7684<strong>\u5904\u7406<\/strong>\uff1b<\/li>\n\n\n\n<li>\u8f93\u51fa\u95e8 (output gate)\uff1a$o_t=\\sigma(W_o\\cdot[x_t,h_{t-1}]+b_o)$ \uff0c\u8868\u793a\u5bf9\u4fe1\u606f\u7684<strong>\u8f93\u51fa\u5f3a\u5ea6<\/strong>\uff1b<\/li>\n<\/ul>\n\n\n\n<p>\u5176\u4e2d\uff0c$[x_t,h_{t-1}]$&nbsp;\u8868\u793a\u4e24\u5411\u91cf\u7684\u5e76\u5217 (concatenate) \u5411\u91cf\uff0c$ht_{t-1}$\u8868\u793a\u795e\u7ecf\u5143 t-1 \u65f6\u523b\u7684\u9690\u85cf\u72b6\u6001\uff0c$\\sigma$&nbsp;\u4e3a sigmoid \u51fd\u6570\u3002<\/p>\n\n\n\n<p>\u2003\u2003\u5728\u6b64\u57fa\u7840\u4e0a\u53ef\u66f4\u65b0\u795e\u7ecf\u5143&nbsp;\ufffd&nbsp;\u65f6\u523b\u7684\u7ec6\u80de\u72b6\u6001&nbsp;\ufffd\ufffd&nbsp;\u4e0e\u9690\u85cf\u72b6\u6001&nbsp;\u210e\ufffd&nbsp;\u5982\u4e0b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ufffd\ufffd=\ufffd\ufffd\u2299\ufffd\ufffd\u22121+\ufffd\ufffd\u2299\ufffd\ufffd\uff0c\u5373\u7ec6\u80de\u72b6\u6001&nbsp;=&nbsp;\u7ecf\u8fc7\u9057\u5fd8\u540e\u7684\u65e7\u7ec6\u80de\u72b6\u6001&nbsp;+&nbsp;\u795e\u7ecf\u5143\u5904\u7406\u540e\u7684\u65b0\u4fe1\u606f\uff1b<\/li>\n\n\n\n<li>\u210e\ufffd=\ufffd\ufffd\u2299tanh\u2061(\ufffd\ufffd)\uff0c\u5373\u9690\u85cf\u72b6\u6001&nbsp;=&nbsp;\u8f93\u51fa\u5f3a\u5ea6&nbsp;\u00d7&nbsp;tanh\u5904\u7406\u540e\u7684\u7ec6\u80de\u72b6\u6001\uff1b<\/li>\n<\/ul>\n\n\n\n<p>\u5176\u4e2d&nbsp;\u2299&nbsp;\u8868\u793a\u54c8\u8fbe\u739b\u79ef (Hadamard product)\uff0c\u5373\u5411\u91cf\u5bf9\u5e94\u5143\u7d20\u76f8\u4e58\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">2.\u591a\u5c42LSTM \u7f51\u7edc\u7ed3\u6784<br><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-16.png\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-16.png'><img class=\"lazyload lazyload-style-3\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"587\" height=\"367\" data-original=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-16.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2253\"  sizes=\"auto, (max-width: 587px) 100vw, 587px\" \/><\/div><\/a><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-17.png\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-17.png'><img class=\"lazyload lazyload-style-3\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"541\" height=\"143\" data-original=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/02\/image-17.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2254\"  sizes=\"auto, (max-width: 541px) 100vw, 541px\" \/><\/div><\/a><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">3.\u6784\u5efaLSTM \u7f51\u7edc<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/03\/1710141364558.png\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/usei.cn\/wp-content\/uploads\/2024\/03\/1710141364558.png'><img class=\"lazyload lazyload-style-3\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"735\" height=\"459\" data-original=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/03\/1710141364558.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2464\"  sizes=\"auto, (max-width: 735px) 100vw, 735px\" \/><\/div><\/a><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">\u58f0\u660e\u6570\u636e<\/h3>\n\n\n\n<h3 class=\"wp-block-heading\">\u58f0\u660e\u7f51\u7edc<\/h3>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><a href=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/03\/image-5.png\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/usei.cn\/wp-content\/uploads\/2024\/03\/image-5-1024x256.png'><img class=\"lazyload lazyload-style-3\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"256\" data-original=\"https:\/\/usei.cn\/wp-content\/uploads\/2024\/03\/image-5-1024x256.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2466\" style=\"width:840px;height:auto\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/a><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">LSTM\u6570\u636e\u683c\u5f0f\uff1a<\/h3>\n\n\n\n<p>num_layers: \u6211\u4eec\u6784\u5efa\u7684\u5faa\u73af\u7f51\u7edc\u6709\u5c42lstmnum_directions: \u5f53bidirectional=True\u65f6\uff0cnum_directions=2\uff1b\u5f53bidirectional=False\u65f6\uff0cnum_directions=1<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u8f93\u5165LSTM\u4e2d\u7684\u6570\u636e\u683c\u5f0f<\/h3>\n\n\n\n<p>\u8f93\u5165LSTM\u4e2d\u7684X\u6570\u636e\u683c\u5f0f\u5c3a\u5bf8\u4e3a(seq_len, batch, input_size)\uff0c\u6b64\u5916h0\u548cc0\u5c3a\u5bf8\u5982\u4e0b<br>h0(num_layers * num_directions, batch_size, hidden_size)<br>c0(num_layers * num_directions, batch_size, hidden_size)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">LSTM\u8f93\u51fa\u6570\u636e\u683c\u5f0f<\/h3>\n\n\n\n<p>LSTM\u8f93\u51fa\u7684\u6570\u636e\u683c\u5f0f\u5c3a\u5bf8\u4e3a(seq_len, batch, hidden_size * num_directions)\uff1b\u8f93\u51fa\u7684hn\u548ccn\u5c3a\u5bf8\u5982\u4e0bhn(num_layers * num_directions, batch_size, hidden_size)<br>cn(num_layers * num_directions, batch_size, hidden_size)<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#x: \u8fd9\u91cc\u6211\u4eec\u5c06x\u7684\u5c3a\u5bf8 (batch_size, seq_len, dims)\u4f9d\u6b21\u662f(3, 5, 4)\r\nx = t.randn(3, 5, 4) \r\nx\r\ntensor(&#91;&#91;&#91; 0.1478, -0.7733, -0.3462,  0.0320],\r\n         &#91;-0.0540,  0.4757, -1.2787,  0.6141],\r\n         &#91; 1.9581,  0.0015,  1.4387, -0.5895],\r\n         &#91;-1.0691, -1.7070,  1.0219, -0.7990],\r\n         &#91;-1.7735,  0.6824,  0.6067, -0.6630]],\r\n\r\n        &#91;&#91;-0.3223, -0.6943,  0.1120, -1.7799],\r\n         &#91;-1.0542,  0.2151, -2.2530,  0.2640],\r\n         &#91;-0.0599, -0.1996,  0.9793, -1.4952],\r\n         &#91;-0.2328,  0.2297, -1.4825,  0.0720],\r\n         &#91; 0.7112, -0.1165,  2.5641, -1.4247]],\r\n\r\n        &#91;&#91;-0.4157, -1.1617, -0.7442, -0.8369],\r\n         &#91; 0.5266,  2.3119,  0.6428,  0.3797],\r\n         &#91;-0.2951, -1.5711,  1.2832, -0.2773],\r\n         &#91; 0.4760,  0.2403,  0.2923,  2.2315],\r\n         &#91;-0.3348, -0.0976,  0.0388,  0.5948]]])\r\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>1.\u7f51\u7edc\u795e\u7ecf\u5143\u7ed3\u6784 $$NDVI=\\frac{NIR\u8fd1\u7ea2\u5916-RED\u7ea2\u8272}{NIR\u8fd1\u7ea2\u5916+RED\u7ea2\u8272}$$ \u5176\u4e2d [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7,90],"tags":[],"class_list":["post-2189","post","type-post","status-publish","format-standard","hentry","category-ai","category-90"],"_links":{"self":[{"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/posts\/2189","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/comments?post=2189"}],"version-history":[{"count":18,"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/posts\/2189\/revisions"}],"predecessor-version":[{"id":2472,"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/posts\/2189\/revisions\/2472"}],"wp:attachment":[{"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/media?parent=2189"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/categories?post=2189"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/usei.cn\/index.php\/wp-json\/wp\/v2\/tags?post=2189"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}