【正文】 of the region. Haimu, a 25yearold khoomei (a local variant of overtone singing) singer, joined the troupe three 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。80s. We sat on the back of pickup trucks for hours. The sky was blue, and we couldn39。其次，本人要感謝自己的所有任課老師，感謝他們?cè)诖髮W(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(shí)和熟練的專業(yè)技能。 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(duì)課題的設(shè)計(jì)，大大提高了自己各方面的能力，例 如對(duì)書本基礎(chǔ)知識(shí)的掌握程度，對(duì)資料的查找方法，對(duì)自己知識(shí)面的擴(kuò)展都有相 對(duì)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(duì)課題的剖解，頭腦中才 逐漸有了輪廓。 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。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(jiǎn)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(jiǎn)易，安裝和使用都非常方便。斷開負(fù)載．用萬用表測(cè)量 78L05的 3腳應(yīng)有 +5v電壓。 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(jí)繼續(xù)判斷是否有人闖入。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(duì)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(cuò)，修改也變得容易。 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]。 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收，如果有人闖入，中斷紅外線，將接受不到紅外線，此時(shí)判斷為應(yīng)當(dāng)報(bào)警，由單片機(jī)控制報(bào)警。 XTAL1:振蕩器反相放大器和內(nèi)部時(shí)鐘發(fā)生電路的輸入端 [14]。否則， ALE 將被微弱拉高?？撮T狗計(jì)時(shí)完成后， RST 腳輸出 96 個(gè)晶振周期的高電平。 在 flash 編程和校驗(yàn)時(shí)， P2 口也接收高 8 位地址字節(jié)和一些控制信號(hào)。作為輸入使用時(shí)，被外部拉低的引腳由于內(nèi)部電阻的原因，將輸出電流（ IIL）。作為輸出口，每位能驅(qū)動(dòng) 8 個(gè) TTL 邏輯電平。在單芯片上擁有靈巧的 8位 CPU 和在系統(tǒng)可編程 Flash，使得 AT89S52 為眾多嵌入式控制應(yīng)用系統(tǒng)提供高靈活、有效的解決方案。系統(tǒng)原理框圖如圖 21 所示。探測(cè)器（報(bào)警器）的種類很多，按所探測(cè)的物理量的不同，可分為微波、紅外、激光、 超聲波和振動(dòng)等方式；按電信號(hào)傳輸方式不同，又可分為無線傳輸和有線傳輸兩種方式 [8]。因此，越來越多的居民家庭對(duì)財(cái)產(chǎn)安全問題十分擔(dān)憂。主動(dòng)式紅外報(bào)警器是點(diǎn)型、線型探測(cè)裝置，除了用作單機(jī)的點(diǎn)警戒和線警戒外，為了在更大范圍有效地防范，也可以利用多機(jī)采取光墻或光網(wǎng)安裝方式組成警戒封鎖區(qū)或警戒封鎖網(wǎng)，乃至組成立體警戒區(qū)。紅外線報(bào)警器對(duì)溫度敏感，溫度越高的物體輻射出的紅外線越 強(qiáng)，當(dāng)感應(yīng)到環(huán)境中存在高出背景強(qiáng)度的輻射時(shí) ,就觸發(fā)報(bào)警。本論文通過對(duì)紅外線防盜報(bào)警器的基本原理和基本電路的概述入手，介紹了紅外線防盜報(bào)警器的發(fā)展背景和國(guó)內(nèi)的發(fā)展?fàn)顩r，并具體論述了在電源電路、紅外線發(fā)射和接受電路、單片機(jī)系統(tǒng)控制電路等。 personal and property safety. Because infrared is not exposed to light, has strong confidentiality and secrecy, therefore in security, alert security device has been widely used, through the infrared transmitting and receiving system for sensing whether someone is breaking into, if the detected someone brok