【正文】 t. Baumgartner still will free fall at a speed that would cause you and me to pass out, and no parachute is guaranteed to work higher than 25,000 feet (7,620 meters). cause there 。ll be traveling fast, so despite the distance, it will not be like 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。突然想到那件藍(lán)格子襯衫；那些被折成各種各樣形狀的信紙；那段從街角深巷伊始的友誼；還有那場還沒有開始就宣告了終結(jié)的邂逅計劃 …… 那些年那些天的非做不可，終于和青春一樣，都將在我們的人生中謝幕。 Have declared the end of the encounter that haven39。 Those were broken into various shapes of stationery。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心劑，或者說，是自以為是的精神寄托罷了。也曾經(jīng)好像已經(jīng)下定了決心去做某件事，但更多的時候是最后又打起了退堂鼓。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 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. 一個人的時候，自己的想法總是特別地清晰。 Originally, this world, can produce a chemical reaction to an event, in addition to resolutely, have to do, and time. 原來，這個世界上，對某個事件能產(chǎn)生化學(xué)反應(yīng)的，除了非做不可的堅決，還有，時間。t want to give vent to out your inner voice can be in the high school children of the feelings in a period, but was eventually infarction when graduation party in the throat, later again stood on the pitch he has sweat profusely, looked at his thrown a basketball hoops, suddenly found himself has already can39。t really grow up, it seems is not so important。 The end of our life, and can meet many things really do? 德州學(xué)院 機電工程系 2021屆 自動化專業(yè) 畢業(yè)論文（設(shè)計） 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?？傆X得自己自己似乎應(yīng)該去做點什么，或者寫點什么。 May be back in the past, to oneself the paranoid weird belief disillusionment, these days, my mind has been very messy, in my mind constantly. Always feel oneself should go to do something, or write something. Twenty years of life trajectory deeply shallow, suddenly feel something, do it. 一字開頭的年齡已經(jīng)到了尾聲。s actions. CSKA said they were surprised and disappointed by Toure39。s 21 win. Michel Platini, president of European football39。s Premier League match at Chelsea on Sunday. I am going to be at the match tomorrow and I have asked to meet Yaya Toure, he told BBC Sport. For me it39。s antiracism taskforce, is in London for the Football Association39。t charge you more than 35% of your pensation if you win the case. If you are thinking about signing up for a damagesbased agreement, you should make sure you39。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。在硬件測試階段， 金老師給予了很多實用的建議和實際的幫助，并細(xì)心地指導(dǎo)我怎樣一步步實現(xiàn) 預(yù)期的效果，最終讓論文得以順利完成，再次表示衷心的感謝！ 在圖書館查詢相關(guān)文獻資料時，圖書館的管理人員也給予了無私的幫助。由于該電源在結(jié)合了線性電源與開關(guān)電源各自優(yōu)點的基礎(chǔ)上還加入了單片機控制，不僅小巧、輕便、輸出特性良好而且還操作簡單，具有控制智能化等特點，因此，十分適用于各種科學(xué)實驗與小功率的電子設(shè)備中，相信會有很好的應(yīng)用前景。首先對系統(tǒng)的輸出電壓進行初始化，設(shè)定為 5V（常用電壓值），然后通過判斷按鍵是 +鍵或是 鍵對系統(tǒng)的輸出電壓進行相應(yīng)的調(diào)節(jié)，并保證輸出電壓不超出設(shè)定范圍，具體的調(diào)節(jié)過程如圖 所示 [46] 。系統(tǒng)輸出電壓在 3V—— 11V之間步進可調(diào)，步進值為 。測試數(shù)據(jù)如表 表 測試數(shù)據(jù) 設(shè)定值 (V) 輸出電壓 (V) 誤差 (V) 1 2 3 4 5 6 7 8 9 從表 中的數(shù)據(jù)可以看出第 1 組和第 9 組輸出電壓與設(shè)定值偏差比較大，設(shè)定值在3V—— 11V時輸出電壓偏差不大。 圖 穩(wěn)壓電路 穩(wěn)壓電路中電阻 R7 和 R8 組成取樣電路，對輸出電壓進行取樣，運放 TL082 構(gòu)成比較電路，對采樣電壓與數(shù)模轉(zhuǎn)換輸出的電壓進行比較以控制調(diào)整電路，三極管 Q1 和 Q2 構(gòu)成調(diào)整電路，調(diào)整電路通過改變?nèi)龢O管的管壓降來調(diào)整輸出電壓 。 數(shù)模轉(zhuǎn)換 DAC0832[3] DAC 模塊是整個系統(tǒng)的紐帶，連接著控制部分與穩(wěn)壓部分，電路如圖 所示 圖 數(shù)模轉(zhuǎn)換電路 德州學(xué)院 機電工程系 2021屆 自動化專業(yè) 畢業(yè)論文（設(shè)計） 該數(shù)模轉(zhuǎn)換電路采用的是 DAC0832 單極性輸出方式，輸出 Vo=B*Vref/256，其中 B 的值為 D0~D7 組成的 8位二進制，取值范圍為 0~255， Vref 是參考電壓，該電壓有電阻 R2和可變電阻 R3分壓所得，通過調(diào)節(jié)可變電阻可以改變參考電壓 Vref。 圖 三端穩(wěn)壓電路 德州學(xué)院 機電工程系 2021屆 自動化專業(yè) 畢業(yè)論文（設(shè)計） AT89C51 主控部分 單片機 AT89C51 是系統(tǒng)的控制核心，主要是通過控制數(shù)摸轉(zhuǎn)換來實現(xiàn)對穩(wěn)壓電源的調(diào)節(jié)，并且控制顯示電路，電路如圖 所示 [9]。在電容量不變時，要改變兩端電壓就必須改變兩端電荷，而電荷改變的速度，取決于充放電時間常數(shù)。電容是一個能儲存電荷的元件。 表 數(shù)碼管字型編碼表 顯示字符 字形 共 陽 極 共 陰 極 dp g f e d c b a 字型碼 dp g f e d c b a 字形碼 0 0 1 1 0 0 0 0 0 0 C0H 0 0 1 1 1 1 1 1 3FH 1 1 1 1 1 1 1 0 0 1 F9H 0 0 0