【正文】 ly found himself has already can39。那些曾經(jīng)所謂的非做不可，只是青蔥年華里自己給自己注射的一支強(qiáng)心劑，或者說(shuō)，是自以為是的精神寄托罷了。ll be traveling fast, so despite the distance, it will not be like 水位檢測(cè)報(bào)警系統(tǒng) 23 diving into the deep end of a pool. It will be like he is diving into the shallow end. Skydiver preps for the big jump When he jumps, he is expected to reach the speed of sound 690 mph (1,110 kph) in less than 40 seconds. Like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him pletely. If he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. His team hopes it39。 Have declared the end of the encounter that haven39。s time, your ideas are always special to clear. Want, want, line is clear, as if nothing could shake his. Also once seemed to be determined to do something, but more often is he backed out at last. Dislike his cowardice, finally found that there are a lot of 水位檢測(cè)報(bào)警系統(tǒng) 22 love, there are a lot of miss, like shadow really have been doomed. Those who do, just green years oneself give oneself an arm injection, or is a selfrighteous spiritual. 一個(gè)人的時(shí)候，自己的想法總是特別地清晰。 The end of our life, and can meet many things really do? 而窮盡我們的一生，又能遇到多少事情是真正地非做不可？ During my childhood, think lucky money and new clothes are necessary for New Year, but as the advance of the age, will be more and more found that those things are optional。s 21 win. Michel Platini, president of European football39。t agree with the disciplinary action your employer has taken against you ? your employer dismisses you and you think that you have been dismissed unfairly. For more information about dismissal and unfair dismissal, see Dismissal. You can make a claim to an employment tribunal, even if you haven39。 = false。 } } private void btnClosePort_Click(object sender, EventArgs e) { if() { ()。 break。 } catch { (串口打開(kāi)失敗 )。 ()。 private void btnOpenPort_Click(object sender, EventArgs e) { port = new SerialPort()。 = 1。 namespace 水位檢測(cè)報(bào)警系統(tǒng)上位機(jī)控制 { public partial class Form1 : Form { SerialPort port。 using ?？傮w來(lái)說(shuō)，我覺(jué)得像課程設(shè)計(jì)這種類型的作業(yè)對(duì)我們的幫助還是很大的，它需要我們將學(xué)過(guò)的相關(guān)知識(shí)系統(tǒng)地聯(lián)系起來(lái)，從中暴露出自身的不足，以待改進(jìn)！ 本次的 項(xiàng)目 設(shè)計(jì)，培養(yǎng)了我 們 綜合應(yīng)用設(shè)計(jì) 項(xiàng)目 及其他 項(xiàng)目 的理論知識(shí)和理論聯(lián)系實(shí)際，應(yīng)用生產(chǎn)實(shí)際知識(shí)解決工程實(shí)際問(wèn)題的能力；在設(shè)計(jì)的過(guò)程中還培養(yǎng)出了我們的團(tuán)隊(duì) 精神，同學(xué)們共同協(xié)作，解決了許多個(gè)人無(wú)法解決的問(wèn)題；在今后的學(xué)習(xí)過(guò)程中我們會(huì)更加努力和團(tuán)結(jié)。 水位變化當(dāng)高水位發(fā)“ 0”時(shí)上位機(jī)接受到對(duì)應(yīng) ASCII 碼為 48，此時(shí)上位機(jī)顯示 “ 警戒！當(dāng)前水位為高水位！ ”。仿真圖如下所示： 圖 9 高水位仿真圖 低 水位狀態(tài) 水位減少到低水位時(shí)：低水位 警示 紅燈閃爍，蜂鳴器低頻率鳴叫 。 LED 的心臟是一個(gè)半導(dǎo)體的晶片，晶片的一端附著 LED燈株在一個(gè)支架上，一端是負(fù)極，另一端連接電源的正極，使整個(gè)晶片被環(huán)氧樹脂封裝起來(lái)。 圖 3 穩(wěn)壓電路圖 水位報(bào)警電路 電源電路 穩(wěn)壓電路 水位傳感器 水位顯示 單片機(jī)STC89C52 水位檢測(cè)報(bào)警系統(tǒng) 7 本電路的主要作用是使從傳感器輸入的電平能夠穩(wěn)定的輸入到單片機(jī)中，是由三極管 901兩個(gè)電阻、和一個(gè)無(wú)極性電容組成。 適用范圍廣、安裝形式多樣側(cè)裝、直裝、頂部和底部安裝、螺紋法蘭安裝達(dá)到多點(diǎn)液位報(bào)警效果。水位檢測(cè)報(bào)警系統(tǒng) 5 3 浮球開(kāi)關(guān)產(chǎn)品參考比重以水（ SG＝ 1）所以使用時(shí)在選用浮球時(shí)須考慮液位的比重 SG，一定大于浮球規(guī)格所標(biāo)示，否則，浮球開(kāi)關(guān)無(wú)法浮動(dòng)。 對(duì)于本設(shè)計(jì)單片機(jī)結(jié)構(gòu)簡(jiǎn)單實(shí)用性強(qiáng)，功能齊全，技術(shù)先進(jìn)，使實(shí)現(xiàn)這設(shè)計(jì)不難實(shí)現(xiàn)。為了獲得大批量的數(shù)據(jù)，得到可靠的分析資料，往往需要長(zhǎng)期、多網(wǎng)點(diǎn)的監(jiān)控記錄。本設(shè)計(jì)只是概念性設(shè)計(jì)了電路部分，并不涉及具體的數(shù)值設(shè)定，經(jīng)過(guò)了實(shí)際應(yīng)用檢測(cè)。 學(xué) 生（簽字）： 系 主 任（簽字）： 指導(dǎo)教師（簽字）： 院 長(zhǎng) （簽字）： 水位檢測(cè)報(bào)警系統(tǒng) 2 目 錄 1． 項(xiàng)目設(shè)計(jì)要求與任務(wù) .......................................................................... 3 2． 項(xiàng)目設(shè)計(jì)正文 ................................................................................... 3 課題背景及研究意義分析 ............................................................ 3 課題現(xiàn)狀 .................................................................................. 4 設(shè)計(jì)思路及方案 ........................................................................ 4 水位傳感方式的選擇 ......................................................... 4 水位傳感器的特點(diǎn)及應(yīng)用 .................................................. 5 系統(tǒng)的組成 ................................................................................ 6 系統(tǒng)工作原理 ................................................................... 6 穩(wěn)壓電路 ......................................................................... 6 水位顯示電路 ................................................................... 7 振蕩電路和復(fù)位 電路 ......................................................... 8 自動(dòng)報(bào)警電路 ................................................................... 8 3．水位檢測(cè)系統(tǒng)的整體電