前言：想要寫出一篇令人眼前一亮的文章嗎？我們特意為您整理了5篇樂觀英文范文，相信會為您的寫作帶來幫助，發(fā)現(xiàn)更多的寫作思路和靈感。

樂觀英文范文第1篇

春天來了的英語作文【1】

Bitterly cold winter may once come, but now it has gone.

As my bike has been stolen, I have to run from one teaching building to another every day.

The bell declares the end of the last lesson and the beginning of a new journey. Tired as I am, at the sight of the bench, I go straight to it. As soon as I get seated, a world of fresh green immediately catches my eyes. Grass sprouts burst through the soil right in the place of the withered grass and turn the dull grey into fresh green. As I look up, I find those tall trees have also put on new clothes. Green, here and there, everywhere!Spring has come, I realize suddenly.

A breeze stirs, sending over breaths of fragrance. I trace it,surprised to find several lovely small white flowers dotted on a tree. Andthere are even some singing birds! I am so delighted with all these tiny lives that my fatigue vanishes all of a sudden.

春天來了的英語作文【2】

The sky shows its purest blue. The sun generously gives out its heat and light, shining evenly on the grass, on the trees,on the roofs of houses, on the people passing by, also on me,quietly and tenderly. There come a couple of young people,strolling leisurely. A group of students are sitting in a circle on the grass and discussing something heatedly. Some are reading English but in low voices afraid of breaking the peace of the campus. Others are lying on the lawn, having a nap, or just enjoying the sunshine as I am.

I feel I am free, free of thinking anything. In such a pleasing environment, doing anything is a great pleasure. I am fully indulged in this tranquility. If only time could stop!

I turn on the radio to enjoy some light music. Much to my disappointment, however, almost all the programs are about the war in Iraq. It is hard to believe that under the same blue sky,some people are suffering from bleeding and death of war while others are enjoying a happy life.

The sun is hidden by the clouds. After a few seconds, it shines brightly again.

Peaceful life seems to have gone, but it will come back one day, I am sure.

春天來了的英語作文【3】

What’s my favourite season? Let me tell you.My favourite season is spring. Spring is a lovely season, I think. There is a garden behind my house. In spring, the trees become green and the flowers give off fragrance(芳香). There are many butterflies and bees over the flowers. The butterflies are dancing and the bees are singing. Sometimes it rains. It usually rains quietly. The rain moistens(滋潤) the trees and the flowers. I think they may say, “We’re very thirsty. The rain is very good. It can help us.” What a beautiful scene! Don’t you think so? And what about your favourite season,could you tell me?

樂觀英文范文第2篇

——怎樣做一名好學(xué)生

昨天，我觀看了教育影片《為了孩子的明天》看后，感觸特別深。

片中的劉剛，一位失足的16歲少年，開始只知道玩，他家住在市區(qū)，樓下盡是網(wǎng)吧、酒吧、歌舞廳，他每天只知道和他結(jié)交的那些不三不四的朋友去這些地方，連他父親病危了也不理睬，照完不誤，后來父親去世了，母親想讓愛子學(xué)好，就遷到郊外去住，可劉剛還是老樣子，網(wǎng)吧、酒吧、歌舞廳他天天都去，這還不夠，他竟在課堂上刁難老師，老師問他頭提及的圓錐和球體那個(gè)表面積大，而他卻反問老師，同體積的男生和女生那個(gè)表面積大？在被老師，被派出所找了幾次后，他的母親桂芬，橫下心來，辭去了工作，帶著劉剛?cè)チ送獾?，從此，劉剛不再進(jìn)網(wǎng)吧、酒吧、歌舞廳了，他知道家里沒錢，便利用課余時(shí)間給別人當(dāng)家教，他用掙得的錢為母親買了一塊蛋糕和一瓶紅酒。

片中的母親，開始以為只要讓孩子吃好、穿好、玩好，孩子就會認(rèn)真學(xué)習(xí)，所以什么事都寵著劉剛，再加上她工作很忙，沒有時(shí)間管理劉剛。后來他覺得劉剛越來越不聽話了，這才意識到這樣下去是不行的，于是他學(xué)習(xí)“孟母三遷”的精神，用環(huán)境改的方法去改變劉剛，鐵石心腸的劉剛終于被媽媽的愛所感動了，開始懂得學(xué)習(xí)，懂得替媽媽分擔(dān)家庭責(zé)任了。而她自己，卻因長時(shí)間患病做苦力活而死掉了，她臨終前告訴劉剛，箱子底下有他爸爸生前留下的一百萬元，一定要將這錢捐給希望工程……

樂觀英文范文第3篇

The film tells the story of Helen Keller in her birth nineteen months time, because of illness, lost valuable listening and vision, so she became a deaf, dumb, and blind severe disabled. She doesn't like normal person study, the life, but Helen Keller in teacher Anne's help, her overcome her sick. Learn to use hand "talk", and mastered English, French, German, Latin, Greece five kinds of words, In her 24 years old, she graduate with excellent results in the famous Harvard University, it completely changed keller life.

See the film, gave me great comprehend: a deaf and dumb people can have made so great achievement, how surprising. If Helen Keller had succumbed to unfortunate fate, then it will become a poor YuWei "parasites". But she didn't head to fate, she with amazing perseverance, indomitable spirit, carvered wonderful life path.

Helen is a disabled, but her mind is key just and free, longing for the future, she himwith a single indomitable heart, created a miracle in human history, and with lovingkindnehands holding the world of the disabled. She is our pride, our example. Helen's life, are tough, will give to us great encouragement, so that those who idling people very regret. Helen unyielding life, not only gives us a lot of enlightenment: we these healthy people, not away your youth, we should treasure this beautiful life, cherish the happineof life. Don't wait for lost regret it, then already too late.

From Helen Keller body, I realized profoundly: a person will achieve, is not the condition quality, but in any struggle and progressive spirit. Had a target, just have the power, for this goal, will certainly encounter all sorts of difficulties, but as long as we march forward courageously, we will overcome all the difficulties and achieving brilliant achievements.

看著海倫·凱勒的電影,我不斷飆升,我是海倫做出這么大的成就,這樣的韌性,是海倫震驚他的精神顛簸的感動。

這部電影講述了海倫·凱勒在她出生19個(gè)月的時(shí)候,因?yàn)樯?失去了寶貴的聽力和視力,所以她成了聾子,啞巴,盲目的嚴(yán)重殘疾。她不喜歡正常的人學(xué)習(xí),生活,但海倫·凱勒的老師安妮的幫助下,她克服她生病。學(xué)習(xí)使用的手“交談”,掌握了英語、法語、德語、拉丁、希臘五種文字,在她24歲,她以優(yōu)異成績畢業(yè)在著名的哈佛大學(xué),它完全改變了凱勒的生活。

看電影,給了我很大的理解:一個(gè)又聾又啞的人能取得這么大的成就,令人驚訝。如果海倫·凱勒屈服于不幸的命運(yùn),那么它將成為一個(gè)可憐YuWei)“寄生蟲”。但她沒有頭的命運(yùn),她以驚人的毅力,頑強(qiáng)的精神,走完了精彩的人生道路。

樂觀英文范文第4篇

Like an elephant drinking water a lot of fun. It with long nose sucked into the water first, and then put the nose into the mouth, the water will automatically flow into his mouth. But sometimes still had water on the outside of the mouth flow, the elephant is really silly!

The elephant is a social animal. A herd of elephants in there is always a respected leading elephant, he will lead the elephant population migration, and to protect elephants from other brutal attack, so a great responsibility, a difficult task.

The elephant is an ancient mammals. For millions of years before, it is with dinosaurs and other animals living on the earth, then the dinosaurs, but the elephant is stubbornly survive, means the elephant to adapt to the environment ability is stronger. Today, the human should endeavor to protect elephants, elephant, as a kind of animal species to survive a few million years is not a problem.

大象的樣子很奇特。它長著四條粗壯的腿，籃球似的頭上長著一條長鼻子和兩只扇形的大耳朵,于是，眼睛就顯得非常小了。龐大的身軀后面還有一根小尾巴，專門用來驅(qū)趕蒼蠅、蚊子的。它那副尖利的長牙也令對手聞風(fēng)喪膽。

大象喝水的樣子很好玩。它先用長鼻子吸進(jìn)水，然后把鼻子放進(jìn)嘴里，水就自動流進(jìn)嘴里了。但有時(shí)水還在往嘴巴外面流，大象可真傻呀!

樂觀英文范文第5篇

【關(guān)鍵詞】HB LED；前照燈；熱管理

一、前照燈應(yīng)用HB LED的優(yōu)勢

LED從上世紀(jì)50年代誕生到現(xiàn)在經(jīng)歷了過半個(gè)世紀(jì)的發(fā)展，適用于照明的高亮度白光LED于90年代中后期取得突破，十幾年來拓展HB LED的應(yīng)用一直都沒有停止過。HB LED應(yīng)用到汽車前照燈領(lǐng)域可獲得的以下特性：

1.超長的使用壽命和優(yōu)越的可靠性

HB LED的預(yù)期使用壽命約50000小時(shí)，遠(yuǎn)遠(yuǎn)超過現(xiàn)有鹵鎢燈、充氣燈甚至氙燈的使用壽命，此外無燈絲、無空腔、結(jié)構(gòu)堅(jiān)固，不易受顛簸振動而影響正常工作，可靠性高；

2.優(yōu)秀的電光轉(zhuǎn)換效率

此前（2011年底）HB LED光效記錄已經(jīng)達(dá)到了230Lm/W，是氙燈的近三倍，更是鹵鎢燈、普通充氣燈的十?dāng)?shù)倍以上。達(dá)到照度要求的情況下，降低功耗能有效降低發(fā)電機(jī)、蓄電池負(fù)荷及導(dǎo)線截面積，利于車輛向輕量化發(fā)展的需求；

3.極短的響應(yīng)時(shí)間

普通燈泡由于燈絲熱惰性，啟動時(shí)間約250mS，氙燈需要建立啟輝高壓，啟動時(shí)間則更長一些。LED的啟動時(shí)間只在nS級，這一優(yōu)勢在極端情況下能為前、后車提供更多的反應(yīng)車距；

二、汽車前照燈對光源的特別要求

1.前照燈的配光應(yīng)使近光具有足夠的照明和不產(chǎn)生眩目，遠(yuǎn)光具有良好的照明①。

前照燈包括遠(yuǎn)、近光燈，不論兩燈制還是四燈制車輛，都要求光束有良好的匯聚和特定的分布，通過透鏡、反光鏡進(jìn)行匯聚要求光源集中，以利于配光鏡對車前照明進(jìn)行配光，照度和配光同等重要。

2.前照燈應(yīng)具有良好的散熱性，防止光源熱堆積，前照燈即使在低溫凝凍的環(huán)境下仍能正常工作②。

汽車前照燈當(dāng)前形勢下仍然是汽車常規(guī)燈具中功率最大的，燈具高溫失控將是很危險(xiǎn)的火災(zāi)隱患。同時(shí)燈具高溫也給其自身也帶來工作穩(wěn)定性和使用壽命的影響。此外，燈具熱堆積將導(dǎo)致光源色溫改變，使雨霧環(huán)境下光線穿透性能和反射光強(qiáng)度等產(chǎn)生變化，將影響駕駛安全。

三、前照燈應(yīng)用HB LED必須解決的關(guān)鍵技術(shù)問題

根據(jù)前照燈對光源要求的以上分析，以及HB LED技術(shù)現(xiàn)狀，筆者認(rèn)為汽車前照燈應(yīng)用HB LED在技術(shù)上主要存在以下兩個(gè)關(guān)鍵問題。

1.開發(fā)小型大功率模塊的需求非常迫切

就率先應(yīng)用HB LED到前照燈的奧迪A8L W12車型而言，為達(dá)到照度要求，每側(cè)使用了76個(gè)LED光源。以近光燈為例，單側(cè)能耗達(dá)到了40W。且構(gòu)件之復(fù)雜、組合之精密遠(yuǎn)遠(yuǎn)超出普通前照燈總成的結(jié)構(gòu)和技術(shù)水平。

過多的LED數(shù)量給燈具設(shè)計(jì)提出了非常高的難度，要解決點(diǎn)光源分散、光束匯聚、水平配光、防眩目等結(jié)合難題。一種方案是將LED布置在反光鏡拋物面內(nèi)，以浪費(fèi)各個(gè)器件部分光通量來確保匯聚后的整體光照度，再對光束進(jìn)行配光。此方案導(dǎo)致成本高而節(jié)能優(yōu)勢削弱，成本浪費(fèi)大。另一種方案是LED單體聚光，分組承擔(dān)車前各區(qū)域的配光，例如對側(cè)方人行道分配的光照由某幾個(gè)LED實(shí)現(xiàn)。此方案的缺陷是個(gè)別LED失效將導(dǎo)致某配光分區(qū)不合格，嚴(yán)格意義上是整個(gè)前照燈不合格。當(dāng)前奧迪A8L W12前照燈采用此方案（遠(yuǎn)、近光共用8個(gè)HB LED），各LED在應(yīng)用時(shí)保留非常多的冗余量以策保險(xiǎn)。此時(shí)器件性能的浪費(fèi)也推高了制造成本。

因此，除了個(gè)別豪華車型撇除成本因素采用HB LED前照燈外，絕大多數(shù)廠家都在等待單顆功率更大的HB LED面世，以期應(yīng)用更少量的LED元件降低設(shè)計(jì)難度和制造成本。

2.大功率HB LED的熱管理難題

HB LED發(fā)光區(qū)別于燈絲發(fā)光和電弧發(fā)光，因?yàn)闆]有熾熱部分將熱量通過輻射耗散，工作時(shí)自身熱能堆積，只能夠通過傳導(dǎo)的形式向外耗散，需要散熱裝置和預(yù)留散熱路徑。另外前照燈在寒冷氣候中還要面臨積雪和凝凍狀況，傳統(tǒng)燈具有燈泡的輻射熱存在，一定程度上對抗了工作中積雪和凝凍。采用HB LED光源后，前照燈就有必要配備化霜裝置，否則無法實(shí)現(xiàn)全天侯照明。同時(shí)，要解決光源自身的散熱，且必須不受前照燈化霜熱量的影響，因此，可靠控制LED的關(guān)鍵是熱管理措施。

首先，結(jié)溫波動的控制。結(jié)溫波動直接影響LED的光效，汽車前照燈照度大小關(guān)系到低能見度環(huán)境的行車安全，且車輛行駛時(shí)，環(huán)境溫度、濕度等因素變化頻繁，燈具所處散熱環(huán)境復(fù)雜，要穩(wěn)定結(jié)溫必須散熱速度可控，且感溫和控制模塊必須靈敏度高、響應(yīng)快；

其次，結(jié)溫高低的控制。結(jié)溫過高是影響LED工作壽命的最重要因素，就目前成本而言，HB LED前照燈總成是普通前照燈總成的好幾倍。高造價(jià)要求控制模塊有足夠的可靠性，驅(qū)動電流必須結(jié)合散熱速度調(diào)節(jié)；

再次，結(jié)溫高低的選定。結(jié)溫影響到LED的色溫和顯色指數(shù)，高色溫時(shí)，人眼的敏感度高，但對車外人員易造成眩目，不符合交通安全法規(guī)要求；高色溫還帶來顯色指數(shù)的下降，加速駕駛員的視覺疲勞。作為制造廠家必須確保不同批次的LED都工作在適當(dāng)?shù)纳珳睾洼^好的顯色性。所以要求控制模塊具有結(jié)溫參數(shù)設(shè)定的功能。

當(dāng)前奧迪A8L W12車型的LED前照燈通過在燈組尾端安裝冷卻風(fēng)扇來解決散熱問題，結(jié)構(gòu)復(fù)雜和可靠性不足，且結(jié)溫高低和散熱工況波動控制不夠理想。

控制芯片方面，當(dāng)前安森美半導(dǎo)體開發(fā)了NCV78663，通過PWM控制平均電流，其高能效、高可靠性、集成控制、LED自檢及動態(tài)控制系統(tǒng)參數(shù)等功能被業(yè)界普遍認(rèn)可，至于大功率HB LED應(yīng)用于汽車前照燈要求對工作結(jié)溫和散熱參數(shù)的精確控制卻并沒有被納入，也就是說仍處于開環(huán)控制系統(tǒng)，一旦出現(xiàn)嚴(yán)苛的工作環(huán)境，熱失控的現(xiàn)象將馬上顯現(xiàn)。

四、總結(jié)

基于汽車前照燈的特別工況和特殊的性能要求，HB LED并沒有如大眾所想象的順利應(yīng)用到汽車前照燈技術(shù)中。但是HB LED的優(yōu)點(diǎn)是顯著的，未來汽車前照燈使用HB LED光源將是必然的趨勢。更高功率的單顆HB LED將簡化前照燈結(jié)構(gòu)，閉環(huán)熱管理的控制系統(tǒng)將充分發(fā)揮其高光效、長壽命的優(yōu)點(diǎn)，使系統(tǒng)更加可靠。彼時(shí)，才是全面普及LED前照燈的時(shí)代。

注釋：

①引用自《GB 4599-1994汽車前照燈配光性能》

②引用自《GB 25991-2010汽車用LED前照燈》2011年5月第一版

參考文獻(xiàn)

[1]GB 4599-1994E汽車前照燈配光性能.

[2]GB 4599-2007汽車用燈絲燈泡前照燈.

[3]GB 4785-2007汽車及掛車外部照明和光信號裝置的安裝規(guī)定.