【正文】 s Liaoning province, decades ago. The solider gave the old man a handmade saddle when they bid farewell. The story inspired Nasun to write Carved Saddle, a song that later became one of his most popular numbers. Now, every year, Nasun recruits young singers and dancers for the troupe. The troupe has also designed a new repertoire, which is mostly based on the daily lives of Mongolian people, especially the lives of nomadic families, and has bined contemporary musical elements with folk songs 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 2021 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 2021 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 trans action 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 2021 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 1617th 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 山西省高等教育自學考試畢業(yè)設計說明書 41 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 。s Poly Theater. Their show, titled Ulan Muqir on the Grassland, depicted the history and development of the art troupe. Being from the region allowed me to embrace the culture of Inner Mongolia and being a member of the troupe showed me where I belonged, Nasun, the art troupe39。s performers of the troupe still tour the region39。t have a formal stage. The audience just sat on the grass. Usually, the performances became a big party with local people joining in. For him, the rewarding part about touring isn39。80s. We sat on the back of pickup trucks for hours. The sky was blue, and we couldn39。s Shaanxi province pass through a stop on the ancient Silk Road, Gansu39。河南理工大學給我提供了再次學習的機會，在這里有良好的學習環(huán)境，一流的實驗設備，高水平的老師教會了我一身的本領，在這里我掌握了各門知識，掌握了各種技能。理解到團結(jié)協(xié)作互相幫助的重要。 在設計過程中許多同學給我提供了很多的幫助，在此表示我的謝意。 在設計過程中遇到了很多難以解決的問題，設計的順利完成和 李輝老師 的大力指導是分不開的， 李輝老師 對工作認真負責的態(tài)度和對學術(shù)科學嚴謹?shù)淖黠L，為我們樹立了榜樣， 老師 平時不僅給我們講解設計方面的知識，還給我們講些書本上沒有的新知識，給我們講如何作一名合格的設計工程師，如何去用積極的態(tài)度面對工作、面對生活、面對人生。 在對皮帶運輸機的 PLC控制 系統(tǒng)設計時，系統(tǒng)組成合理，但可能考慮不夠周全，有些控制電路如皮帶跑偏沒能考慮進去。實現(xiàn)了轉(zhuǎn)速傳感器直接檢測到皮帶運輸機的速度，通過信號傳輸線路傳輸?shù)?主令控制器中。 皮帶運輸系統(tǒng)中， PLC作為現(xiàn)場控制設備，能夠可靠、準確地完成控制操作，且可以通過與上級工控機通信，是現(xiàn)代工業(yè)控制中 比較先進的控制方案，應用前景十分廣泛。另外還必須利用軟件手段，進一步提高系統(tǒng)的安全可靠性。 (1)設備選擇 在選擇設備時，首先選擇較高抗干擾能力的產(chǎn)品，它包括電磁兼容性，尤其是抗外部干擾能力，如采用浮地技術(shù)、隔離性能好的山西省高等教育自學考試畢業(yè)設計說明書 33 PLC系統(tǒng)；其次應了解生產(chǎn)廠家給出的抗干擾指標，如共模抑制比、差模抑制比、耐壓能力、允許在多大電場強度和多高頻率的磁場強度環(huán)境中工作等。反轉(zhuǎn)設定： LD X002 ANIM1 AND M2 OUT Y002 CJ 檔位設定 當需要返回正轉(zhuǎn)狀態(tài)時，需要重新設定： LD X001 ANI M2 AND M1 OUT Y001 CJ P60 （ 2）復位 當需要復位時： LD X15 OUT Y00 PLC 控制系統(tǒng)的抗干擾設計策略 PLC控制系統(tǒng)的抗干擾是一個系統(tǒng)工程，要求制造單位設計生產(chǎn)出具有較強抗干擾能力的產(chǎn)品，且需要使用 部門在工程設計、安裝施工和運行維護中予以全面考慮，并結(jié)合具體情況進行綜合設計，才能保證系統(tǒng)的電磁兼容性和運行可靠性。 （ 2）自動控制，通過軟件控制，程序如下 LD X002 OUT M0 在正常停止情況時候，需要延遲一段時間，以便能把貨物順利卸載。 （ 1）手動時候：它是通過拉線來使設備立即停止的一種保護裝置。 LD M8002 ZCP D6 D8 D16 AND M12 CJ P90 AND M13 CJ P60 AND M14 CJ P90 當電壓或者電流超出安全范圍時，閃爍電路開始工作，閃爍后自動停止。首先進行電流安全檢測，程序如下；當電流測定值大于較大的設定值或者小于較小的設定值，調(diào)用閃爍電