【正文】 效果。系統(tǒng)的最大的特點(diǎn)是操作簡(jiǎn)單，部署方便，并且較好的防止錯(cuò)誤操作發(fā)生，盡可能多的給用戶提示信息。 但本系統(tǒng)也存在設(shè)計(jì)上的不足，首先因?yàn)?初次設(shè)計(jì)制作完整的系統(tǒng)，在初期階段需求分析和考慮數(shù)據(jù)庫設(shè)計(jì)的時(shí)候都做的不全面，以至不能很好的保證數(shù)據(jù)的完整性，在長時(shí)間使用刪除一些數(shù)據(jù)后，會(huì)有一些臟數(shù)據(jù)留存，也可能有其他一些問題發(fā)生。另外，對(duì)教材科工作的了解不夠深入，會(huì)有些功能和操作方式還沒有考慮到。 [2] 求是科技 . [M]. 北京： 人民郵電出版社 ,2021。 [4] Jesse Liberty[美 ]. Programming [M] 瞿杰 趙立東 譯 . 北京： 電子工業(yè)出版社 ,2021。 [6] 郝剛 . 開發(fā)指南 [M]. 北京： 人民郵電出版社 ,2021。John Kauffman[美 ]. C篇 [M] 孟憲瑞 。 第 20 頁 共 33 頁 致 謝 本文是在趙攀老師的熱情關(guān)心和指導(dǎo)下完成的，他淵博的知識(shí)和嚴(yán)謹(jǐn)?shù)闹螌W(xué)作風(fēng)使我受益匪淺，對(duì)順利完成本課題起到了極大的作用。文中除了特別加以標(biāo)注地方外，不包含他人已經(jīng)發(fā)表或撰寫過的研究成果，也不包含為獲得成都信息工程學(xué)院或其他教學(xué)機(jī)構(gòu)的學(xué)位或證書而使用過的材料。 關(guān)于學(xué)位論文使用權(quán)和研 究成果知識(shí)產(chǎn)權(quán)的說明： 本人完全了解成都信息工程學(xué)院有關(guān)保管使用學(xué)位論文的規(guī)定，其中包括： （ 1）學(xué)校有權(quán)保管并向有關(guān)部門遞交學(xué)位論文的原件與復(fù)印件。 （ 3）學(xué)?？梢詫W(xué)術(shù)交流為目的復(fù)制、贈(zèng)送和交換學(xué)位論文。 （ 5）學(xué)?？梢怨紝W(xué)位論文的全部或部分內(nèi)容（保密學(xué)位論文在解密后遵守此規(guī)定）。 特此聲明！ 作者簽名： 年 月 日 第 22 頁 共 33 頁 Billy saw service with the infantry in Europe, and was taken prisoner by the Germans. After his honorable discharge from the Army in 1945, Billy again enrolled in the Ilium School of Optometry. During his senior year there, he became engaged to the daughter of the founder an d owner of the school, and then suffered a mild nervous collapse. He was treated in a veterans39。F has sixtyeight thousand employees in Ilium. That calls for a lot of lenses and a lot of frames. Frames are where the money istion of coalmines was far distant and there was no dread of scarcity. There were still extensive mines to be worked in the two Americas. The manufactories, appropriated to so many different uses, lootives, steamers, gas works, amp。 but the consumption had so increased during the last few years, that certain beds had been exhausted even to their smallest veins. Now deserted, these mines perforated the ground with their useless shafts and forsaken galleries. This was exactly the case with the pits of Aberfoyle. Ten years before, the last butty had raised the last ton of coal from this colliery. The underground working stock, traction engines, trucks which run on rails along the galleries, subterranean tramways, frames to support the shaft, pipes in short, all that constituted the machinery of a mine had been brought up from its depths. The exhausted mine was like the body of a huge fantasticallyshaped mastodon, from which all the ans of life have been taken, and only the skeleton remains. Nothing was left but long wooden ladders, down the Yarrow shaft the s, carpenters, outside and inside laborers, women, children, and old men, all were collected in the great yard of the Dochart pit, formerly heaped with coal from the mine. Many of these families had existed for generations in the mine of old Aberfoyle。 feet, and silence succeeded to the bustling life which had till then filled the Aberfoyle mines. One man alone remained by James Starr. This was the overman, Simon Ford. Near him stood a boy, about fifteen years of age, who for some years already had been employed down below. James Starr and Simon Ford knew and esteemed each other well. Goodby, Simon, said the engineer. Goodby, Mr. Starr, replied the overman, let me add, till we meet again! Bill became rich. He had two children, Barbara and Robert. In time, his daughter Barbara married another optometrist., and Billy set him up in business. Billy39。t resume practice. He had a housekeeper. His daughter came over almost every day. And then, without any warning, Billy went to New York City, and got on an allnight radio program devoted to talk. He told about having e unstuck in time. He said, too, that he had been kidnapped by a flying saucer in 1967. The saucer was from the pla Tralfamadore, h e said. He was taken to Tralfamadore, where he was displayed naked in a zoo, he said. He was mated there with a former Earthling movie star named Montana Wildhack. 第 24 頁 共 33 頁 Some night owls in Ilium heard Billy on the radio, and one of them called Billy39。s wedding. He hadn39。s friends. Their suction cups were on the ground, and their shafts, which were extremely flexible, usually pointed to the sky. At the top of each shaft was a little hand with a green eye in its palm. The creatures were friendly, and they could see in four dimensions. They pitied Earthlings for being able to see only three. They had many wonderful things to teach Earthlings, especially about time. Billy promised to tell what some of those wonderful things were in his next letter. Billy was working on his second letter when the first letter was published. The second letter started out like this: 39。When a Tralfamadorian sees a corpse, all he thinks is that the dead person is in a bad condition in that particular moment, but that the same person is just fine in plenty of other moments. Now, when I myself hear that somebody is dead, I simply shrug and say what the Tralfamadorians say about dead people, which is so it goes.39。s day off. There was an old typewriter in the rumpus room. It was a beast. It weighed as much as a storage battery. Billy couldn39。t noticed. He wasn39。s heart, at any rate, were glowing coals. What made them so hot was Billy39。Father? Daddy, where are you?39。t answer her, so she was nearly hysterical, expecting to find his corpse. And then she looked into the very last p lace there was to lookwhich was the rumpus room. 39。t you answer me when I called?39。I didn39。 said Billy. The orchestration of the moment was this: Barbara was only twentyone years old, but she thought her father was senile, even though he was only fortysixsenile because of damage to his brain in the airplane crash. She also thought that she was head of the family, since she had had to manage her mother39。s business interest