【正文】 years ago. Along with a sixmember band, he performs fast songs and soft ones that he writes－ all while playing the horsehead fiddle.Although I learned the piano since childhood and grew up listening to various kinds of music, to me, the folk music of Inner Mongolia is the root, he says. Performing in remote villages is pleasant. I feel at home on the boundless grasslands, and the warm people there make me feel fulfilled. The first round of spring auction season in Beijing ended last week, but it failed to create much spring in the art market. Although two pieces of Chinese painting fetched more than 100 million yuan, the decline in trading volume and sa le rate showed a downturn this year. In the ―Grand View: Chinese Painting Highlight‖ session at China Guardian 2020 spring auctions, Pan Tianshou’s representative work Eagle, Rock and Flora hit a record auction price of 279 million yuan, while Li Keran’s masterwork Jinggang Mountain fetched million yuan, an unexpected high in recent years. However, the trading volume fells to billion yuan from billion yuan in the same period the year before. The Huangchen 2020 Spring Auctions, which recorded million yuan in total sales, experienced the same. The section number went down to 5 from 12 pared to last year. According to expert Shao Jianwu, the art market did not attract much excitement this year due to the booming stock market and the persistent problems of fery and fake deals. The two pieces of Chinese painting notched up high price this spring due to their own value not due to a revival in the market. The successful transaction of two works with a hammer price of more than 100 million yuan once again confirms that valuable and rare works of high quality always earn the longlasting high price. Chinese painting and calligraphy is still the pillar of the market. However, the overall sales rate has dropped slightly, which reflects the demand for the ordinary auction goods has weakened,‖ said the president of China Guardian’s Hu Yanyan. Besides, the entry of new buyers also makes certain changes to the direction of purchasing. In a word, the overall market trend is very unpredictable. Although China Guardian 2020 Spring Auctions has achieved remarkable results, it does not mean that the market has walked out of the predicament. We still have to wait for the big economic boom to invigorate the art market.‖ Even so, the hot pursuit of some special items appeared this spring. A special session of China Guardian Spring Auctions titled ―Fine Gilt—Bronze Buddhist Images‖ achieved a great deal with total sales volume of million yuan and 92 percent sale rate. The 5th Shamar Rinpoche Statue from 16 17th century of Tibet was sold for million yuan. The Beijing Chengxuan Auctions featured almost 2,800 items of coins and stamps in three sessions with good sale rate. The Huachen Auctions also set a special session of photographs under the condition of largescale decline of auction sessions. There was a palpable dull thud of disappointment that acpanied the return of the imperial entourage of Zhen Huan to her homeland. It followed a couple years of hushed excitement as Chinese fans were fed tidbits about their proud concubine who was supposed to conquer the high ground of the North American market. Zhen Huan is, of course, the title character of The Legend of Zhen Huan, a 2020 television series that swept China off its feet and later took other Asian countries by storm. Two years ago, it was reported that HBO, a premium cable service headquartered in the United States, was going to air it in North America after some modification. Now, a condensed version that provides English subtitles but no dubbing has finally been made available on Netflix for online streaming. This version, highly anticipated as a milestone in China39。s performers of the troupe still tour the region39。80s. We sat on the back of pickup trucks for hours. The sky was blue, and we couldn39。此 次畢業(yè)設(shè)計(jì)是我大學(xué)四年最難忘的一件事，也是給各位老師的一個(gè)匯報(bào)，在以后的路上，我會更加充滿信心向更深處學(xué)習(xí)。其次，本人要感謝自己的所有任課老師，感謝他們在大學(xué)四年里的關(guān)心和培養(yǎng)，并使本人掌握了高深的專業(yè)知識和熟練的專業(yè)技能。經(jīng)過這一次設(shè)計(jì)，體會頗多，感覺到平時(shí)的粗心大意，以及不完善的理論知識讓我錯過了一次就要成功的那種感覺，而是做了很多次的修改，但在制作電路的過程中感覺到了一種力量，那種力量可以讓我廢寢忘食的不斷改善調(diào)試電路，可以讓自己興奮的久久的為了電路而深思，可以讓自己在深夜寫著畢業(yè)設(shè)計(jì)說明書，回顧自己的畢業(yè)設(shè)計(jì)制作過程時(shí)，心中油然而生一陣感慨，有失落 ，有興奮，有喜悅，有苦惱，但我覺得它值得我這樣去做，因?yàn)樗粌H讓我有了一次對于電子技術(shù)的實(shí)踐機(jī)會，更讓我學(xué)會怎樣去面對制作過程中遇到的困難，怎么去解決困難，讓我學(xué)會了獨(dú)立思考，讓我隱隱約約記憶起以前學(xué)過的知識，原來不知道有何實(shí)用性的枯燥電路原理的知識，現(xiàn)在我在實(shí)際應(yīng)用卻覺得少了解了好多東西，心中無限后悔。 22 總結(jié) 本人設(shè)計(jì)的課題是紅外線防盜報(bào)警器，經(jīng)過幾 個(gè)月的思考和準(zhǔn)備，通過對課題的設(shè)計(jì)，大大提高了自己各方面的能力，例 如對書本基礎(chǔ)知識的掌握程度，對資料的查找方法，對自己知識面的擴(kuò)展都有相 對的提高，但在這其中，也有自己茫然和不知所措的一面，當(dāng)初決定做此課題時(shí) ，不知該從何下手，頭腦中也一片空白，后來經(jīng)過老師對課題的剖解，頭腦中才 逐漸有了輪廓。 要減少此類誤報(bào)，在安裝前要準(zhǔn)確設(shè)定安裝位置、安裝角度以及系統(tǒng)線路走向，避免安裝紅外探測器時(shí)面對空調(diào)、換氣扇，同時(shí)若在室外安裝應(yīng)該做好遮陽防護(hù)。 無論是損壞性故障還是漂移性故障都將使系統(tǒng)誤報(bào)警，要減少由此產(chǎn)生的誤報(bào)警必須提高產(chǎn)品的設(shè)計(jì)水平和工藝水平，在作系統(tǒng)設(shè)計(jì)的同時(shí)，還需作可行性設(shè)計(jì)，如冗余設(shè)計(jì)、三防設(shè)計(jì) (防潮、防鹽霧、防霉菌 )等。這類故障通常是由元器件的損壞或生產(chǎn)工藝不良 (如虛焊等 )造成。該系統(tǒng)所使用的都是一些新型實(shí)用的芯片，性能優(yōu)良價(jià)格便宜，軟件設(shè)計(jì)方面 也十分簡單，適用于開發(fā)實(shí)用型家庭防盜報(bào)警器，且系統(tǒng)適用于一般家庭的 220V 電壓，原理簡易，安裝和使用都非常方便。使 U1插座的 9各腳的電壓符合要求。斷開負(fù)載．用萬用表測量 78L05的 3腳應(yīng)有 +5v電壓。中斷子程序流程圖如圖 43 所示 NO YES 圖 43 中斷服務(wù)程序流程 保護(hù)現(xiàn)場 重設(shè)定時(shí)初值 1s 到了嗎？ 取反 恢復(fù)現(xiàn)場 中斷返回 19 系統(tǒng)的主程序 ORG 0000H AJMP MAIN ；轉(zhuǎn)向主程序 ORG 000BH ：定時(shí)器 TO 中斷入口 LJMP BJ ；轉(zhuǎn)向中斷服務(wù)程序 ORG 0030H MAIN： MOV SP， 50H ；設(shè)置堆棧棧底 MOV R1,0AH；設(shè)置循環(huán)計(jì)數(shù)器初值 MOV P3， 00H；設(shè)置 P3 口為正常狀態(tài) MOV P1,0ffH；使 VD1~VD6 發(fā)紅外光 MOV TMOD,01H；設(shè) T0 為定時(shí)方式 1 MOV TH0,3CH；設(shè)置定時(shí) 100ms 初值 MOV TL0,0B0H SETB EA 。 主程序的流程圖如 41所示 .程序開始后，系統(tǒng)初始化結(jié)束后判斷是否有人闖入，若有則報(bào)警，若無則回到上一級繼續(xù)判斷是否有人闖入。而 1 秒時(shí)間可以讓定時(shí)器重復(fù)定時(shí) 100ms 十次實(shí)現(xiàn)。軟件設(shè)計(jì)的好壞也直接決定了系統(tǒng)的運(yùn)行質(zhì)量，在編寫軟件之前，對系統(tǒng)的流程進(jìn)行設(shè)計(jì)是十分必要的，這樣可以保證在編寫軟件時(shí)思路清晰，不易出錯，修改也變得容易。 D2 為快速開關(guān)二極管。 圖 34 聲光報(bào)警部分電路圖 14 電源電路 電源開關(guān) SW1 送入 220V 經(jīng)過保險(xiǎn)絲后送入變壓器，保險(xiǎn)絲起保護(hù)電路的作用 [18]。如圖 34 所示。 12 圖 32 紅外線發(fā)射電 路圖 紅外線接收部分 紅外線接收電路主要由 D1~D6 六個(gè)紅外線接收二極管組成，主要功能是用來接收 D7~D12 發(fā)射的紅外線，正常情況下能夠成功接