[科技不怕問]怎麼用聲納尋找失聯飛機?

[導讀]如果在水下進行搜索，聲納是最有效的探測手段之一。

網友「阿海」：

馬航飛機失去聯繫這麼久，連衛星都出來搜索了，還是沒有發現。大部分殘骸會沉入水中吧？看到搜救力量已經在利用聲納進行水下搜索，這種方式靠譜麼？

var flash_vid = 'j0014a0avhd', flash_title = '馬航客機失聯第七天', flash_pic = 'http://image.techweb.com.cn/upload/roll/2014/03/14/201403149474_628.jpg', flash_hits = '190', showVideoPic = false, flash_url = 'http://v.qq.com/page/j/h/d/j0014a0avhd.html', flash_type = '1';#sidebar{ float: right; width:343px; position: relative; height:556px; border-left:1px solid #4b4b4b; background:#383838; }.nowPlay { color:#fff; font-size:14px; padding:9px 16px 6px; font-weight: bold; background:#2F2F2F; }#Cnt-Main-Article-QQ .nowPlay p { margin-bottom: 0; color:#fff; }#video_box{ float: left; width: 640px; height:518px; overflow:hidden;} .video_list{ float: right; width: 342px;position:absolute; left: 0; top: 43px; }.video_list ul { background:#383838; *zoom:1; }.video_list li{ height: 102px; }.list_box{ padding: 10px 10px 18px 17px; height: 47px;}.list_box p{ color: #d3d3d3; font-size: 14px; margin-top: 4px;}.bt{ line-height: 24px;}.bt span{ float: left; color: #8a8a8a;}.bt em{ float: right;font-family:simsun}.live{ display: block;float: none;background: url(images/live.png) no-repeat right;padding-right: 37px;}.list_box_over{ padding: 11px 13px 13px 17px; }.v_img{ float: left; position: relative; margin-right: 10px; display: inline; }.v_img p{ position: absolute; bottom: 0px; left: 0px;background-color: rgba(0,0,0,.7);width: 98px;}.v_img p span{ background: url(images/v_Icon.png) no-repeat 0px 2px; text-align: center; margin-left: 8px; padding-left: 15px; color: #cfb28c;}.v_intr span{ color:#fff; font-size:12px; }#Cnt-Main-Article-QQ .v_intr p{ color: #666666; margin-top: 4px; line-height: 22px; font-size:12px; margin-bottom:0;}#scr{ width: 8px; background-color:#4b4b4b; position: absolute; height: 470px; right:0;top:0; }#scr span { display:block; width:8px; height:40px; background:#818181;position: absolute; }.listvideoNLayout { overflow-x: hidden; overflow-y: auto; scrollbar-arrow-color: #61605d; scrollbar-face-color: #818181;scrollbar-darkshadow-color: #1e1d1b;scrollbar-highlight-color: #818181;scrollbar-3dlight-color: #1e1d1b;scrollbar-shadow-color: #818181;scrollbar-track-color: #4b4b4b; }.listvideoNLayout::-webkit-scrollbar{width:8px}.listvideoNLayout::-webkit-scrollbar-button{display:none}.listvideoNLayout::-webkit-scrollbar-button:vertical:end:increment{display:block;height:8px;background-color:#383838}.listvideoNLayout::-webkit-scrollbar-track{height:200px;background-color:#383838;border-radius:3px}.listvideoNLayout::-webkit-scrollbar-track-piece:vertical:start{width:4px;background:#4B4B4B}.listvideoNLayout::-webkit-scrollbar-track-piece:vertical:end{width:4px;background:#4B4B4B}.listvideoNLayout::-webkit-scrollbar-thumb:vertical{background:#818181;cursor:pointer}#video_btn:hover { background-color:#fb9004; }.video_btn { position:absolute; left:641px; height:558px; width:15px; border-right:1px solid #262626; background-color:#383838; background-image: url(http://mat1.gtimg.com/news/dcimages/icon_botn_left.png); background-repeat:no-repeat; background-position:center; }.nowLive { background:#1c1c1c; } .nowLive .v_intr span { color:#FF7900; font-size:12px; }.video_btn:hover { background-image: url(http://mat1.gtimg.com/news/dcimages/icon_botn_left_cur.png); background-repeat:no-repeat; }.video_btn_right { background-image:url(http://mat1.gtimg.com/news/dcimages/icon_botn_right.png);}.video_btn_right:hover { background-image: url(http://mat1.gtimg.com/news/dcimages/icon_botn_right_cur.png); background-repeat:no-repeat;}.list_box_over_cur { background:#272727; }#sidebar { position:absolute; left:656px; }.relativeVideo { position:absolute; float: left; margin-bottom:35px}#ch { height:106px; }#Cnt-Main-Article-QQ { z-index:1; }.reltit h3 { float:left; width:auto; padding-right: 48px; }.reltit .v_close { position:static; padding-left:0; }#icon_v_close { position:static; float:left; margin-top: 9px; *margin-top: 7px; width: 19px; } .relativeVideo, .relInfo, .relVideo { z-index: 1; }#mod_player { float:left; position:static; }.convideo { float:left; width:640px; }.tjvideo { float:left; width:640px; border-top:1px solid #303030;font-size: 14px; padding-left:10px; }.tjvideo span { float:left; color:#FC8D00; font-weight:bold; line-height:38px; }#invideocon .tjvideo ul { float:right; width:360px; font-size:14px; line-height:38px; margin-bottom:0; } #invideocon .tjvideo ul a,#invideocon .tjvideo ul a:visited,#invideocon .tjvideo ul a:link,#invideocon .tjvideo ul a:active { color:#fff; border:none; }#invideocon .tjvideo ul a:hover { color:#FC8D00; }#showHotBox { float:left; width:439px; } 馬航客機失聯第七天

時長：0'32''

播放：190

來源：央視網

馬航客機失聯第七天收起 推薦視頻： 自動播放

正在播放

//推薦視頻手動更新//var hotVideoInfo = {txt: '騰訊視頻', url: 'http://v.qq.com'};try{ var hotVideoInfo = {txt:'', url: ''};}catch(e){ var hotVideoInfo = {txt: '騰訊視頻', url: 'http://v.qq.com'};}//最新推薦數據的方法var showTvData = {};qq.getScript('http://mat1.gtimg.com/www/js/tcomment/jquery-1.6.2.min.js', function(){ jQuery.noConflict(); //滾動上報 // 處理滾動條和綁定上報 jQuery('#mod_player').css("height",518) var _uin = UI.cookie("o_cookie") ? UI.cookie("o_cookie") : ''; var _reportISfirst = false; var _algfilever; var _algsubver; var _algver; var _reportARR = []; var dynaHadReport = {}; var _vidDatas = {}; var _automatic = true;//判斷是否播放 var autoplay = 1;//默認自動播放 //設置相關視頻的cookie //aboutVideo == 1 表示自動播放 == 0 表示不自動播放 var aboutVideoCookie = qq.cookie("aboutVideo_v"); if(aboutVideoCookie == null){ autoplay = ARTICLE_INFO.tpl.dev == 'tips' ? 0 : 1;//視頻是否自動播放 }else if(aboutVideoCookie == '0'){ autoplay = 0; jQuery('input[action-type=select_video]').attr("checked",false) }else{ autoplay = 1; } //判斷是否選中連續播放的按鈕 jQuery('input[action-type=select_video]').bind('click',function(){ var check = jQuery(this).is(':checked'); if(check){ var aboutDate = new Date();// aboutDate.setTime(aboutDate.getTime() + 7*24*60*60*1e3); qq.cookie('aboutVideo_v', '1', aboutDate, '', 'qq.com'); }else{ var aboutDate = new Date(); aboutDate.setTime(aboutDate.getTime() + 7*24*60*60*1e3); qq.cookie('aboutVideo_v','0',aboutDate,'','qq.com'); } registerZone2({bossZone: 'ZDBF', url: ''},1); }); var scrollPostData = function(){ var $lis = jQuery("#listvideoN li"); var $lisKey = $lis.eq(3); var fold = $lisKey.offset().top + $lisKey.height(); $lis.first().attr('_pageindex', 1); // 上報基礎信息 var request = {}; request.vid = flash_vid; request.pageindex = 1; request.ctype = 9; request.cmd = 1803; request.val2 = 9; request.int1 = (_algfilever || 0); request.int2 = (_algver || 0); request.int3 = (_algsubver || 0); request.t = (new Date()).getTime(); var creatIMG = function(request){ var img1 = document.createElement("img"); img1.src = 'http://rcgi.video.qq.com/web_report?cmd='+ request.cmd +'&vid='+ request.vid +'&host='+ARTICLE_INFO.site+'.qq.com&ctype='+request.ctype+'&int1='+request.int1+'&int2='+request.int2+'&int3='+request.int3+'&val2='+request.val2+'&str2='+request.pagevids+'&itype=0&_='+request.t+'&val=1&str1=0'; }; // 上報第一頁 request.pagevids = $lis.first().attr('vid')+ '+' + _vidDatas[1].join('+'); creatIMG(request); // 延遲加載 jQuery('[node-type=listvideoNLayout]').scroll(function(){ $lis.each(function(i, element) { var $li = jQuery(this); var liTop = $li.offset().top; if (fold >= liTop) { // 上報曝光的數據，5個為一組上報 var pageIndex = $li.attr('_pageindex'); if (!!pageIndex) { request.pageindex = pageIndex; request.pagevids = _vidDatas[pageIndex].join('+'); } // 上報過的分頁不再上報 if (!dynaHadReport[pageIndex] && pageIndex != 1) { request.cmd = 1803; creatIMG(request); dynaHadReport[pageIndex] = []; } } }); return false; }); }; /** * 統計上報 * @param {String} act 操作行為[show/click] * @param {Number} type 上報類型 * @param {String} str2 統計目標的數據 */ var _report = function(act,type,option,str2,str1) { var self = this, url, data, cmd, isLazy; if (!type) { return; } str2 = str2 || ''; str1 = str1 || '0'; if (act == 'show') { isLazy = false; if (option.vid) { cmd = '1803'; } else { cmd = '1801';//只有專輯有多類型，新舊版統計不一樣 } } else if (act == 'click') { isLazy = true; if (option.vid) { cmd = '1804'; } else { cmd = '1802';//只有專輯有多類型，新舊版統計不一樣 } } data = { cmd: (cmd || 1803), vid: option.vid, itype: 0, ctype: 9, str2: encodeURIComponent(str2), val2: type, idx: 0, int1: (_algfilever || 0), int2: (_algver || 0), int3: (_algsubver || 0), t: (new Date()).getTime() }; var img1 = document.createElement("img"); img1.src = 'http://rcgi.video.qq.com/web_report?cmd='+ data.cmd +'&vid='+ data.vid +'&host='+ARTICLE_INFO.site+'.qq.com&ctype='+data.ctype+'&int1='+data.int1+'&int2='+data.int2+'&int3='+data.int3+'&val2='+data.val2+'&str2='+data.str2+'&itype=0&_='+data.t+'&val=1&str1='+str1+''; }; //bosszone 統計 var tongji_1 = function (type,id){ var bossID = id || 1604; var expicNews; var userQQ = UI.cookie("o_cookie") ? UI.cookie("o_cookie") : ''; if(type == 'show'){ expicNews = 'EXrvideoList'; bossID = id || 1604; }else{ expicNews = 'rvideoList'; bossID = id || 1408; } var iurl = 'http://btrace.qq.com/collect?sIp=&iQQ=' + userQQ + '&sBiz=' + 'tvlist' + '&sOp='+ expicNews +'&iSta=&iTy=' + bossID + '&iFlow=&sUrl=' + escape(location.href) + '&iBak=&sBak=&ran=' + Math.random(); gImage_1 = new Image(1,1); gImage_1.src = iurl; } //獲取自定義屬性值 var dataProcess = function(actionData, name) { var d = actionData; var arr = d.split("&"); var data = {}; for (var i = 0; i < arr.length; i++) { var t = arr[i].split("="); var s1 = t[0], s2 = t[1]; data[s1] = s2; if (s1 == name) { return data[s1]; } } return data; }; ///相關視頻開始 //獲取高度 var _css = function (el, prop) { return parseInt(jQuery.css(el[0], prop)) || 0; }; var _height = function (el) { return el[0].offsetHeight + _css(el, 'marginTop') + _css(el, 'marginBottom'); }; //創建視頻 var t, videoInfo, videoPlayer, _vIn, _vOut, showVideoPic, _vedeoCurr = 0, isFirstVideo = false, isShowVideoList = false, isFirstTv = false, initShowVideo = null, isShowTvBox;//判斷是否是展開的模式 //autoplay = ARTICLE_INFO.tpl.dev == 'tips' ? 0 : 1;//視頻是否自動播放 var showVideo = function(){ //qq.getScript('http://imgcache.gtimg.cn/tencentvideo_v1/tvp/js/tvp.player_v2.js', function(){ var pram = dataProcess(jQuery('#listvideoN li').first().attr('action-data')); videoInfo = new tvp.VideoInfo(); videoInfo.setVid(pram.id); videoInfo.setTitle(pram.title); videoPlayer =new tvp.Player(); videoPlayer.create({ width:640, height:518, video:videoInfo, pic:flash_pic, modId:"mod_player", //mod_player是剛剛在頁面添加的div容器 autoplay:autoplay, flashWmode:'transparent' }); //渲染視頻播放列表 初始化滾動事件 var videos = []; var parm = {}; jQuery('#listvideoN li').each(function(i){ var data = dataProcess(jQuery(this).attr('action-data')); videos.push({vid:data.id,title:data.title}); _reportARR.push(data.id); }); var running = false; var ul = jQuery('#listvideoN'); var li = jQuery("li", ul); var itemLength = li.size(); var ulSize = liSize * itemLength; var scroll = 1;//滾動幾個 _vedeoCurr = 0;//從第幾個開始 var v = 4;//默認顯示幾個 ul.css({ margin: "0", padding: "0", position: "relative", "list-style-type": "none", "z-index": "1" }); var liSize = _height(li); jQuery('div[node-type=listvideoNLayout]').css({ position: "relative", height:511+'px', width:'342px' }); //自動播放滾動動畫 function go(to){ var T = to * liSize; if(to > 1){ var pos = jQuery("li", ul).eq(_vedeoCurr-1).position(); jQuery('[node-type=listvideoNLayout]').scrollTop(pos.top); } jQuery("li", ul).removeClass('list_box_over_cur'); jQuery("li", ul).eq(to).addClass('list_box_over_cur'); }; //視頻播放回調 videoPlayer.onplaying = function(vid){ //只上報一次數據 if(!_reportISfirst){ var vid_arr = _reportARR.slice(0,4); _reportISfirst = true; //bossZone 統計 tongji_1('show',1604); //滾動統計 if(jQuery('#listvideoN').children().length > 4){ //scrollPostData(); }else{ _report('show',9,{vid:flash_vid},vid_arr.join('+'),'0'); } }; var videotitleN = jQuery('#videotitleN'); var data = dataProcess(jQuery("#"+videoPlayer.getCurVideo().getVid()).attr('action-data')); //展開右側 if(!isFirstVideo && !autoplay){ jQuery('#invideocon').css({width:'1000px'}); jQuery('#relVideo').css({width:'1000px'}); jQuery('#video_btn').removeClass('video_btn_right'); jQuery('#video_btn').addClass('isShowTv'); isFirstVideo = true; } //動態更換title videotitleN.attr('href',data.url); videotitleN.html(data.title); var listvideoNList = jQuery('#listvideoN li'); listvideoNList.removeClass("list_box_over_cur nowLive"); //判斷用戶是否選中為自動播放狀態 jQuery("#"+videoPlayer.getCurVideo().getVid()).addClass("list_box_over_cur nowLive"); //判斷是否已經收起視頻 if(!isShowTvBox){ itShowVideo.showTv(); }else{ itShowVideo.hideTv(); } }; //下一集播放 videoPlayer.ongetnext = function(vid){ //展開右側 if(!isFirstVideo && autoplay){ jQuery('#invideocon').css({width:'1000px'}); jQuery('#relVideo').css({width:'1000px'}); jQuery('#video_btn').removeClass('video_btn_right'); jQuery('#video_btn').addClass('isShowTv'); isFirstVideo = true; //滾動統計 if(jQuery('#listvideoN').children().length > 4){ scrollPostData(); } } if(itemLength > 4){ _vedeoCurr++; go(_vedeoCurr); } var nextvid = ""; var nextTitle = ""; _flashplayer_continueToPlay = true; for(var i = 0;i < videos.length;i++){ if(videos[i].vid == vid && i < videos.length-1){ nextvid = videos[i+1].vid; nexttitle = videos[i+1].title; break; } }; //統計 _report('click',9,{vid:flash_vid},nextvid,'3'); //bossZone 統計 tongji_1('show',1912); videoInfo.clear(); videoInfo.setVid(nextvid); videoInfo.setTitle(nextTitle); //判斷用戶是否選中為自動播放狀態 return videoInfo; }; isFirstTv = true; //}, 'utf-8', true); return { hideTv:function(){ videoPlayer.pause(); }, showTv:function(){ videoPlayer.play() } } accessPlayer = 1; if(qq.G('focusHub')){ qq.G('focusHub').focus(); } }; //初始化視頻列表數據 var createVideoList = { init:function(){ jQuery.ajax({ url:'http://sns.video.qq.com/fcgi-bin/recommand?id='+ flash_vid +'&tablist=9&playright=2&size=24&uin='+_uin+'&otype=json', dataType:'jsonp', jsonp:'callback', scriptCharset : 'utf-8', success:function(json){ var page = 0; var pageIndex = 1; var html = []; var parm = {}; var data = json.tablist; var getVidData = []; if(flash_hits == 0){ html.push(createVideoList.str({id:flash_vid,title:flash_title,picurl:flash_pic,vv:'',playurl:flash_url,imgsrc:flash_pic,page:1})); }else{ html.push(createVideoList.str({id:flash_vid,title:flash_title,picurl:flash_pic,vv:'播放：'+flash_hits,playurl:flash_url,imgsrc:flash_pic,page:1})); } if(json && data){ if(data.length > 0){ var list = data[0].cover_info; _algfilever = data[0].algfilever; _algsubver = data[0].algsubver; _algver = data[0].algver; var liPage = 5; var j = 0; var pageIndex = 0; for(var i = 0;i < list.length;i++){ parm = { id:list[i].id, title:list[i].title, playurl:list[i].playurl, picurl:list[i].picurl, vv:'播放：'+list[i].vv || '', imgsrc:list[i].pic2url, act:'click' }; //分組數據 if(i%liPage === 0){ j++; pageIndex++; _vidDatas[j] = []; } parm.page = pageIndex; _vidDatas[j].push(list[i].id); html.push(createVideoList.str(parm)) } } } jQuery('#listvideoN').html(html.join('')); //判斷是否自動播放 var video = qq.G('relVideo'), txt = qq.G('relInfo'); if(flash_type == 1){ isShowTvBox = false; video.style.cssText = 'width:656px; height:588px; display:block'; txt.style.cssText = 'height:0'; qq.G("invideocon").style.cssText = 'width:656px;' qq.G('ch').style.height = '588px'; initShowVideo = new showVideo(); //isShowTvBox }else{ isShowTvBox = true; video.style.cssText = 'height:0;'; txt.style.cssText = 'height:105px; display:block'; initShowVideo = new showVideo(); } //點擊播放按鈕 qq.EA(qq.G('relInfo'), 'click', function(){ var video = qq.G('relVideo'), txt = qq.G('relInfo'); isShowTvBox = false; txt.style.display = 'none'; //qq.showOpacity(video, 200, 20); video.style.width = '656px'; video.style.display = 'block'; qq.G('ch').style.height = '588px'; jQuery('div[node-type=listvideoNLayout]').css({ position: "relative", height:'511px', width:'342px' }); //默認是否展示右側的數據 if(!isShowVideoList){ qq.G('invideocon').style.width = '1000px'; qq.G('relVideo').style.width = '1000px'; qq.G('video_btn').className = 'video_btn isShowTv'; } jQuery('#relVideo').animate({ height:588 },50); initShowVideo.showTv(); }); } }); }, str:function(data){ var html = ''+ ''+ '

'+ ''+ ''+ ''+data.title+''+ '

'+data.vv+'

'+ ''+ ''+ ''; return html; } }; createVideoList.init(); qq.EA(qq.G('v_colse'), 'click', function(){ isShowTvBox = true; if (!jQuery('#relVideo').is(":animated")) { qq.G('relVideo').style.height = '1px'; qq.G('relInfo').style.display = 'block'; qq.G('relInfo').style.height = '105px'; qq.G('ch').style.height = '105px'; qq.showOpacity(qq.G('relInfo'), 200, 50); qq.G('invideocon').style.width = '660px' initShowVideo.hideTv(); } }); qq.EA(qq.G('relInfo'), 'mouseover', function(){ qq.addClass(qq.G('relInfo'), 'relStatus'); }); qq.EA(qq.G('relInfo'), 'mouseout', function(){ qq.removeClass(qq.G('relInfo'), 'relStatus'); }); if(qq.G('moreTvBtn') && qq.G('moreTv')){ var mbtn = qq.G('moreTvBtn'), mList = qq.G('moreTv') qq.EA(qq.G('relVideo'), 'mousemove', function(){ mbtn.style.visibility = 'visible'; }); qq.EA(qq.G('relVideo'), 'mouseout', function(){ mbtn.style.visibility = 'hidden'; }); qq.EA(mbtn, 'mouseover', function(e){ clearTimeout(_vOut); if(!_vIn) { qq.animate(qq.G('moreTv').style, 'right', -339, 0, 50); mbtn.style.visibility = 'hidden'; _vIn = true, _vOut = null; } }); qq.EA(mList, 'mouseover', function(e){ clearTimeout(_vOut); }); qq.EA(mList, 'mouseout', function(e){ clearTimeout(_vOut); _vOut = setTimeout(function(){qq.animate(mList.style, 'right', 0, -339, 50); mbtn.style.visibility = 'hidden';}, 500); _vIn = false; }); qq.B.ie6 && qq.each(qq.GT(mList, 'li'), function(a, b){ a.onmouseover = function(){ this.className = 'hover'; } a.onmouseout = function(){ this.className = ''; } }); } //播放相關視頻 var listvideoN = jQuery('#listvideoN'); listvideoN.delegate('li','click',function(e){ e.stopPropagation(); e.preventDefault(); var self = jQuery(this); var act = self.attr('act'); if(!self.hasClass('nowLive')){ var data = dataProcess(self.attr('action-data')); var title = data.title || ''; var id = data.id; _vedeoCurr = self.index() == 0 ? 0 : self.index(); videoInfo.setVid(id); videoInfo.setTitle(title); videoPlayer.play(videoInfo); //判斷是否列表第一個不給上報 if(act == 'click'){ _report('click',9,{vid:flash_vid},id,'0'); //bossZone 統計 //tongji_1('click'); } //數據上報 registerZone2({bossZone:'rvideoList',url:''},1); } }); listvideoN.delegate('li','mouseenter',function(e){ jQuery(this).addClass('list_box_over_cur'); }); listvideoN.delegate('li','mouseleave',function(e){ jQuery(this).removeClass('list_box_over_cur'); }); jQuery('#video_btn').bind('click',function(e){ if(!jQuery(this).hasClass('isShowTv')){ //統計代碼 if(!_reportISfirst){ var vid_arr = _reportARR.slice(0,4); _reportISfirst = true; //bossZone 統計 tongji_1('show',1408); //滾動統計 if(jQuery('#listvideoN').children().length > 4){ scrollPostData(); }else{ _report('show',9,{vid:flash_vid},vid_arr.join('+'),'0'); } } jQuery('#invideocon').css({width: '1000px'}); // jQuery('#sidebar').show(); jQuery('#relVideo').css({width:'1000px'}); jQuery(this).removeClass('video_btn_right'); jQuery(this).addClass('isShowTv'); }else{ jQuery('#invideocon').css({width: '656px'}); //jQuery('#sidebar').hide(); jQuery('#relVideo').css({width:'1000px'}); jQuery(this).addClass('video_btn_right'); jQuery(this).removeClass('isShowTv'); } }); ///相關視頻結束//展示最新推薦(function(){ var Jsonp={ loadScript: function(url){ var script = document.createElement("script"); script.type = "text/javascript"; if(script.readyState){ script.onreadystatechange = function(){ if(this.readyState == "loaded" || this.readyState == "complete"){ this.onreadystatechange = null; document.body.removeChild(this); } }; }else { script.onload = function(){ document.body.removeChild(this); }; } script.setAttribute('src', url); document.body.appendChild(script); }, encodeParameters: function(arg,parameters){ var paras = []; for (parameter in parameters){ paras.push(escape(parameter) + "=" + escape(parameters[parameter])); } return paras.length > 0? (arg == -1 ? '?':'&')+paras.join('&'):''; }, request: function(url, param){ if(typeof url === 'string') var str = url.indexOf('?'); this.loadScript(url + this.encodeParameters(str,param) ); } }; //hotVideoInfo 語法容錯部分給默認值 if(typeof hotVideoInfo == 'undefined'){ hotVideoInfo = {}; } //請求數據 showTvData.getData = function(json){ var parm = {}; var doc = document; var showBox = doc.getElementById('hotRecommendedComent'); var showPrent = doc.getElementById('showHotBox'); if(json){ if(json.data && json.data.length > 0){ if(ARTICLE_INFO.site == 'sports'){ parm = { url:"http://v.qq.com/sports/", title:json.data[0].title || '' }; }else{ parm = { url:"http://v.qq.com/news/?vid="+json.data[0].vid || '', title:json.data[0].title || '' }; } } else if(hotVideoInfo && hotVideoInfo.txt){ parm = { url: hotVideoInfo.url, title: hotVideoInfo.txt } } showBox.innerHTML = parm.title; showBox.href = parm.url; setTimeout(function(){ showPrent.style.display = "block"; },1000) } }; //判斷頁面是哪個頻道 //體育頻道下面展示看體育的數據 if(ARTICLE_INFO.site == 'sports'){ if(hotVideoInfo && hotVideoInfo.txt){ showTvData.getData(hotVideoInfo); }else{ Jsonp.request('http://v.qq.com/c/kbs_headline.js', { "callback": "showTvData.getData", "t": new Date().getTime() }); } }else{ if(hotVideoInfo && hotVideoInfo.txt){ showTvData.getData(hotVideoInfo); }else{ Jsonp.request('http://v.qq.com/c/todayHot.js', { "callback": "showTvData.getData", "t": new Date().getTime() }); } } })()});

騰訊科技：

3月12日，中國海軍發言人梁陽稱，為了搜救失聯客機，海軍搜救力量將通過吊放式精測聲吶、成像聲吶、水下電視、水下機器人等，發揮艦艇夜航優勢，進行24小時不間斷搜索。

目前搜索的關鍵目標之一是失聯飛機的黑匣子，如果落入水中，黑匣子會發出一定頻率的信號，可以通過聲納來探測到。

啟動艦船的聲納搜索非常重要

聲納是各國海軍進行海底探測的主要技術，除聲音外其他的介質，如光線，雖然在水中有一定的穿透能力，但是在最清澈的海水中，目力所及也只能看到幾米到幾十米內的物體。電磁波在水中也衰減很快，而且波長越短，衰減越大，即使用大功率的低頻電磁波，也只能傳播幾十米。而聲波在水中傳播的衰減就小得多，在深海聲道中爆炸一個幾公斤的炸彈，在兩萬公裡外還可以收到信號。

聲納搜索這麼重要，那麼如何使用聲納進行搜索？

被動聲納搜索：

可以通過接收探測目標發出的信號來發現目標。

黑匣子上配有水下信標（ULB）的裝置，它在遇水後能夠被激活，可發出頻率為37.5KHz的水下聲音脈衝信號，能夠持續30天左右。黑匣子作為客機沉入海底後唯一還可能發出信號的部件，如果能憑藉聲音信號定位黑匣子，就可以大大縮小對客機殘骸的搜索麵積。

但由於黑匣子體積小，發射功率有限，船載聲納對其水聲信號的探測距離也不過幾公裡，因此對它的搜尋也需要像在水面上搜尋漂浮物一樣，出動配備聲納的艦艇進行拉網式搜索。

黑匣子的水聲信標發出的聲音頻率為37.5KHz，船艦聲納為了探測遠距離目標，工作頻率在10KHz以下（頻率越低在水下傳播的越遠），通過頻道匹配就能接收到目標的信息。

主動聲納搜索：

如果此次波音777客機黑匣子的水下信標在事故中損壞，那麼就要使用效率更低的主動聲納探測了。

艦船上安裝有側掃聲納，側掃聲納的工作頻率一般在100KHz以上，能對海底物體進行直接成像。艦船可以先利用側掃聲納發現海底疑似客機殘骸的物體，然後再派潛水員潛到海底確定疑似物是否是飛機殘骸。

但是測掃聲納工作時，航速不能太高，並且船隻兩側掃描範圍一般也只有數百米。如果事先不能將客機可能墜海的地點限定到一個較小的區域，面對茫茫大海，除了派出更多配備聲納的艦船進行長時間、大面積的搜尋外，沒有更好的辦法。（喬輝）