第一篇：3D打印機(jī)英文論文

TSINGHUA SCIENCE AND TECHNOLOGY

ISSN

1007-0214 04/38 pp24-28 Volume 14, Number S1, June 2009

Abstract: Rapid prototyping(RP)is a computerized fabrication technology that additively builds highly com-plex three-dimensional physical objects layer by layer using data generated by computer, for example CAD or digital graphic.Three-dimensional printing(3DP)is one of such technologies that employ ink-jet printing technology for processing powder materials.During fabrication, a printer head is used to print a liquid on to thin layers of powder following the object's profile as generated by the system computer.This work looks at redesigning 3DP machine, using piezoelectric demand-mode technology head in order to improve accuracy, surface finishing and color quality of constructed models.The layers created with aforesaid system are be-tween 25 to 150 μm(steps of 25 μm).Key words: prototyping;three-dimensional printing(3DP);piezoelectric head Perusing Piezoelectric Head Performance in a New

3-D Printing Design

RAHMATI Sadegh，?,**?

SHIRAZI Farid, BAGHAYERI Hesam

Mechanical Engineering Group, Faculty of Engineering, Azad Islamic University, Majlesi Branch, Iran;

? Mechanical Engineering Department, Khaje Nasir Toosi University, Tehran, Iran

Introduction

Solid freeform fabrication(SFF)technologies are manufacturing/prototyping technologies that are char-acterized by layer-by-layer addition of material to fab-ricate components.These techniques are also known as layered manufacturing and rapid prototyping.The layer-by-layer building approach allows significantly more complex parts to be built in one fabrication step than was previously possible thus simplifying process planning.SFF technology therefore can automate the process planning and fabrication of a part under computer con-

trol so that the only input needed is a solid model of [1,2]the part.Over the last decade, many different technologies for SFF have evolved.Broadly, the SFF techniques available currently can be classified as stereo lithogra-phy, solid fusion and solidification, laminated object

manufacturing, and powder-based techniques.The ste-reo lithography technique selectively solidifies a liquid photopolymer while solid fusion and solidification fuse/melt the material and deposit it layer-by-layer.The laminated object manufacturing technology cuts out laminates from sheets of part material and glues or fuses them together.In most methods of SFF, special

support structures are needed to support overhanging

[1,3]

features of the part.Received: 2008-11-09;revised: 2009-03-30 To whom correspondence should be addressed.E-** mail: s_farid_sh@yahoo.com;Tel: 98-912-1350938

The two main powder-based techniques that have

been commercialized are selective laser sintering and three-dimensional printing(3DP)printing.For powder-based methods, no support structures are typically re-quired to create complex shapes.Powder is selectively consolidated into a part and the remaining powder can be removed.In the SLS process, a thin layer of powder is deposited in a workspace container and the powder is then fused together using a laser beam that traces the shape of the desired cross-section.The process is re-peated by depositing layers of powder thus building the part layer-by-layer.In the 3DP process, a binder material selectively binds powder deposited in layers.RAHMATI Sadegh et al：Perusing Piezoelectric Head Performance in a New …

Ink-jet printing head(IJH)technology is used to print

the binder in the shape of the cross-section of the part on each layer of powder(Fig.1)[4,5]

.Fig.1 3-D Printing process

Two kinds of drop-on-demand heads can be used in IJH systems, piezoelectric and thermal heads

[6], and the thermal heads are used in current 3DP systems.Since thermal heads have some drawbacks, hence piezoelec-tric head has been employed for new generation of 3DP machines.In addition, piezoelectric technology can help to inject the live cells in to vital textures in order to create bones, members and dentures without any chemical or physical changes in cells.1 Ink-jet Head Technologies

1.1 Thermal heads In thermal systems there is a heating element as a thin-film resistor.When an electrical pulse is applied to the head, a high current passes through this resistor and the fluid in contact with it is vaporized, forming a vapor bubble over the resistor.This vapor bubble expands in

fluid reservoir and is ejected as a droplet through the nozzle(Fig.2)[6,7].Fig.2 Schematic of a thermal head

1.2 Piezoelectric heads In this type of system a volumetric change in the fluid reservoir is induced by the application of a voltage pulse to a piezoelectric material element that is cou-pled, directly or indirectly, to the fluid.This volumetric

change causes pressure/velocity transients to occur in

the fluid and these are directed so as to produce a drop

that issues from a nozzle(Fig.3)

[6,8]

.A result of simu-lated droplet ejection is shown in Fig.4.Fig.3 Schematic of a piezoelectric head

Fig.4 A result of simulated droplet ejection in piezo-

electric heads

[9]

When a voltage pulse is applied in the direction or-thogonal to the polarization direction of the piezoelec-tric element, it is deformed and the fluid in the channel reservoir is pressurized.When the pressure wave gen-erated in the channel is reflected between nozzle and common fluid chamber and resonated, the pressure ap-

plied to the nozzle change in time, and as a result drop-let is ejected

[9]

.1.3 Comparison between thermal and

piezoelectric technology

Thermal demand-mode ink-jet systems can achieve ex-tremely high fluid-dispensing performance at a very low cost.However, this performance/cost has been achieved by highly tailoring the fluid: thermal ink-jet systems are restricted to fluids that can be vaporized by the heater element(without igniting the fluid)and their performance/life can be degraded drastically if other fluids are used.In practice, thermal ink-jet systems are limited to use for aqueous fluids while the work of piezoelectric demand-mode ink-jet technology does not depend on thermal process and because of this reason, does not 26

create thermal stress on the fluids which is being jetted from the nozzles of head.Meantime, the diversity of fluids that can [6]be jetted by the piezoelectric heads grows vastly.In addition, some thermal ink-jet sys-tems in comparison with piezoelectric type produce more inconsistent droplets with satellite and misting, which causes dimensional error, rough surface [9]

finish-ing, and low color quality in constructed models.Control of the Ejection and Impact Phenomena As the ink-jet printed models structures strongly de-pend on the velocity, the initial size and the path of the droplet just before spreading, it is essential to control

these different characteristics as a function of the driv-ing parameters of the printing head

[10]

.To obtain this data, the mathematical equation was used based on two different voltages(5 and 12 V).This reveals that the increase of the amplitude(up to 12 V)leads to the formation of a satellite droplet, which catches up with the main one later.Moreover, this shows that the final volume increases with the amplitude of the pulse(Fig.5).Fig.5 Resonance frequency vs.droplet volume

The equation is given as[10]

V ? πr 2V /(2 f)d

(1)

where Vd is the volume of droplet, r is the radius of the nozzle, V is the velocity of droplet, and f is the reso-nance frequency.As can be inferred from Eq.(1), when Vd is increased, the necessary velocity of droplet in-creases rapidly.Also, the frequency of head movement to print the layers decreases contemporary.Consider-ing these conditions, accurate dimensional layers of model are possible to be made.The only downside to these attitudes is the rate of building layers because the

Tsinghua Science and Technology, June 2009, 14(S1): 24-28

frequency of working head has direct effect on the ve-locity of printing layers.Nozzles

Another important parameter to build accurate layers is the inner nozzle diameter.When a nozzle diameter is decreased, the droplet volume decreases, however, the viscous resistance in the nozzle is greatly increased, and the energy loss grows rapidly.Figure 6 shows the relationship between the nozzle diameter and the drop-let velocity.Fig.6 Nozzle diameter vs.droplet velocity at differ-ent

viscosity

In a situation where the binder viscosity is increas-ing, if nozzle throat area gets smaller, velocity drop is significant.In other words, increasing binder viscosity has predominant effect on velocity drop compared with increasing velocity by changing nozzle cross sectional area.The relation between inner nozzle diameters，droplet size, and droplet volume is shown in Table 1.Table 1 Relation between inner nozzle diameter, drop-

let size, and droplet volume[11]

Inner nozzle diameter

Droplet size Droplet volume

(μm)

(μm)(pL)35 20 50 55 90 70

180 Binder Properties

To adjust the fluid properties of the organic suspen-sions to be compatible with the type of printing head, viscosity and surface tension must be 5-20 mPa s and 35-40 mJ/N, respectively.This will provide the ratio of Re / we

1/ 2

to be in the adequate range(1-10)for

ejection of a consistent droplet.RAHMATI Sadegh et al：Perusing Piezoelectric Head Performance in a New … 27

Fig.7 Nozzle configuration of piezoelectric head

In fact successful drop ejection occurs when the ra-1/2R/Weetio has a value ranged between 1 and 10 with e,where Re is the Reynolds number(vrρ/η);We, the Weber number(V2rρ/σ);ρ, η, and σ are the ink density, viscosity, and surface tension, respec-tively;r, the radius of the R/We???r/?nozzle;and v the fluid veloc-ity.When this ratio is too small, viscous forces are

dominant which implies large pressure for ejection;in-versely, if this ratio is too large, a continuous column is ejected that can lead to the formation of satellite drops behind the main drop.As demonstrated previously, piezoelectric head tech-nology is capable of jetting the binder from the nozzle continuously and more efficiently.Moreover, this tech-nology assures that the binder drops after leaving the nozzle, would rest accurately at the interested position.Therefore, in general, piezoelectric technology is the most adapted of the ink-jet printing technologies to flu-id jetting or micro dispensing and in particular to rapid prototyping applications.Hence, a piezoelectric head with these specifications has characteristics as given in Table 2.[6][12] Table 2 Piezoelectric head characteristics Print method: Nozzle configuration:

Drop-on-demand ink-jet Monochrome: 48 nozzle(120dpi)Cyan, Magenta, yellow, light cyan, light magnet Bi-direction with logic seeking 238 CPS

3000 million dots/nozzle 110 mm/s(720×2880)dpi Color(48 nozzle×5)Print direction: Print speed: Print head life: Feed speed: Max resolution:

Figure 7 shows the nozzle configuration viewed from the back of the print head.The required energy to eject the binder droplet includes the energy to form the

droplet surface and the kinetic energy of the droplet.In addition, a considerable amount of energy is consumed for the flow of the binder in the nozzle.Fur-ther, even after droplet ejection, more energy is con-sumed until the residual oscillation of the binder is terminated.Conclusions

The advantages and disadvantages of piezoelectric and thermal heads were investigated.Based on the results, parameters such as accuracy, life time and diversity of materials, and piezoelectric heads were recognized as the most adapted to rapid prototyping applications.Based on the new design, piezoelectric demand-mode technology was employed to jet the binder from noz-zles.The printed layer samples with piezoelectric head are shown in Fig.8.Fig.8 A single layer printed by new 3-D printer

Parameters such as dimensional accuracy, surface finishing, and color quality of fabricated models of the new 3DP system demonstrate a significant improve-ment over the common 3DP models.Moreover, the ca-pability of layer dispending mechanism is improved by up to 3 times(minimum layer thickness is 25 μm), and the surface finishing of fabricated models is also im-proved.The fabricated models are colorful, with excellent accuracy and improved surface quality, compared with the fabricated models using current commercial 3-D printers.As a matter of fact, thin layer thickness has significant effect on surface texture quality of the model.Applying piezoelectric technology enables the binder to penetrate the required depth, resulting in layer thickness as thin as 25 μm and improving surface texture quality.This work is currently in progress and initial results have been promising.References

[1] Kumar A V, Dutta A, Fay J E.Electrophotographic printing of part and binder powder.Rapid Prototyping Journal, 2004, 10: 7-13.[2] Noorani R.Rapid Prototyping Principles and Application.New Jersey: John Wiley & Sons Inc., 2006.[3] Waterman P J.Rapid Prototyping.DE March, 1997.[4] Bak D.Rapid prototyping or rapid production? 3-D print-ing processes move industry towards the latter.Assembly Automation, 2007, 23(4): 340-345

[5] Jee H J, Sachs E.A visual simulation technique for 3-D printing.Advances in Engineering Software, 2000, 31(2): 97-106.[6] Piqué A, Chrisey D B.Direct-Write Technologies for Rapid Prototyping Applications.A Division of Harcourt, Inc., 2002.Tsinghua Science and Technology, June 2009, 14(S1): 24-28

[7] Sachs E, Vezzetti E.Numerical simulation of deposition

process for a new 3DP printhead design.Journal of Mate-rials Processing Technology, 2005, 161(2): 509-515.[8] Carrión A.Technology forecast on ink-jet head technology

application.Rapid Prototyping Journal, 1997, 3(3): 99-115.[9] Takeuchi Y, Takeuchi H, Komatsu K, Nishi S.Improve-ment of drive energy efficiency in a shear mode piezo-ink-

jet head.Hp Company Report, 2005.[10] Kar S, McWhorter S, Ford S M, et al.Piezoelectric me-chanical pump with nanoliter per minute pulse-free flow delivery for pressure pumping in Micro-channels.Analyst，1997, 123: 1435-1441.[11] Microdrop Technology Co., 2006, Brouchour.[12] Noguera R, Lejeune M, Chartier T.3-D fine scale ceramic

components formed by ink-jet prototyping process.Jour-nal of the European Ceramic Society, 2005, 25(12): 2055-2059.

第二篇：如何寫英文論文

如何寫英文論文

一、開頭段常用思路

1.介紹當(dāng)前背景、現(xiàn)象、形勢(shì)+說出自己的觀點(diǎn)

2.介紹雙方觀點(diǎn)+說出自己的觀點(diǎn)

3.提個(gè)問題+介紹雙方觀點(diǎn)+說出自己的觀點(diǎn)

4.介紹當(dāng)前背景、現(xiàn)象、形勢(shì)+介紹雙方觀點(diǎn)+說出自己的觀點(diǎn)

5.說個(gè)與題目相關(guān)的故事+說出自己的觀點(diǎn)

6.介紹當(dāng)前背景+介紹對(duì)方觀點(diǎn)+說出自己的觀點(diǎn)

7.連續(xù)發(fā)問式

8.說出名人名言或諺語+介紹當(dāng)前背景、現(xiàn)象、形勢(shì)+說出自己的觀點(diǎn)

9.以調(diào)查數(shù)據(jù)為佐證

10.以典型事實(shí)為佐證

二、理由常用思路

1.說出自己觀點(diǎn)的好處或贊成這種觀點(diǎn)的原因

2.批駁對(duì)方觀點(diǎn)的弱點(diǎn)

3.為自己觀點(diǎn)的不足做辯解

4.結(jié)合當(dāng)前的背景和現(xiàn)象

5.圍繞涉及不同對(duì)象

三、段落展開方法

1.列舉事實(shí)法

2.舉例子論證法

3.對(duì)比論證法

4.類比論證法

5.假設(shè)論證法

6.結(jié)合統(tǒng)計(jì)數(shù)據(jù)，名人名言和諺語，專家和權(quán)威的觀點(diǎn)

四．結(jié)尾段常用思路

1.重申觀點(diǎn)

2.重申觀點(diǎn)+改寫各理由段理由

3.靈活的結(jié)尾

4.重申觀點(diǎn)+靈活結(jié)尾

5.讓步+重申觀點(diǎn)

文章寫得連貫 關(guān)聯(lián)詞

并列和遞進(jìn)

And moreover further furthermore also likewise similarly tooin like manneragainin the same waybesidesin addition

轉(zhuǎn)折和讓步

But nevertheless otherwiseon the other handconverselyon the contraryhowever yet stillin spite ofall the sameeven soafter allalthougheven if

原因和結(jié)果

Because since as forbecause ofhenceconsequentlythussofor this reasonaccordinglythereforeas a resultit follows that

比較與對(duì)照

Similarlylikewiseequally importantin factat the same timeaccordinglyin the same waylikeon the contrary

different fromin contrastin comparisondespiteyetbuthoweverunlikenot only but alsoyears ago…today

the former…the latterthe first…whereas the secondwhereasneverthelessinsteadhere…therethis…thatthen…now

some…othersonce…now

提示陳述順序

Firstto begin withto start within the first placenextsecondthirdin the second placebesidesin additionwhat’s morefurthermoremoreoverto make matters worsefinally

Last but not least

舉例

For instancefor exampleto illustrateas an illustration

結(jié)論

In a wordin shortin briefto sum upin summary

in conclusionto conclude

表明時(shí)間順序

Thennowcurrentlyat presentsomewhat laterpresentlyThereuponthereaftereventuallyat the same timemeanwhile First secondin the mean timesoonnextfinallyat last 復(fù)述

Brieflythat is to sayin factindeedin other words 表明方位

To the rightin the distancestraight aheadon the left belowbetweenadjacent tounderbeyondaround close toopposite toon top ofoveracross from

above next to

第三篇：英文論文

淺談高中英語寫作中語域知識(shí)的習(xí)得

總論：新課程標(biāo)準(zhǔn)中＂語域＂的概念在中學(xué)階段英語教學(xué)中是個(gè)新鮮詞匯，第一次提到，并且明確列入評(píng)分標(biāo)準(zhǔn)之中。語域知識(shí)的習(xí)得是學(xué)生寫作能力發(fā)展過程中的一大難點(diǎn)，因此，了解其含義及要求，對(duì)于我們教師當(dāng)前如何有效指導(dǎo)學(xué)生的寫作就顯得尤為重要和迫切。比方說：photograph與photo均可指照片、圖片，但photograph是newspaper language，屬于正式體，一般常見于報(bào)刊雜志，而photo則是隨便體，使用較為自由，這主要是語域功能的差異造成的。

關(guān)鍵字：高中英語課程標(biāo)準(zhǔn)、語域、中學(xué)寫作、新要求

一、語域知識(shí)的習(xí)得是《英語課程標(biāo)準(zhǔn)》的新要求

普通高中《英語課程標(biāo)準(zhǔn)》（人民教育出版社2003年4月第一版，第55頁）所附的寫作評(píng)價(jià)標(biāo)準(zhǔn)中明確提到：對(duì)學(xué)生的作文主要從內(nèi)容要點(diǎn)、語言使用效果、結(jié)構(gòu)和連貫性、格式和語域以及與目標(biāo)讀者的交流五個(gè)方面進(jìn)行評(píng)價(jià)?？梢圆捎镁C合性評(píng)價(jià)，也可以采用分析性評(píng)價(jià)。通常采用分檔次按等級(jí)評(píng)分制。其中第五檔分類高分標(biāo)準(zhǔn)如下：

第五檔（新課程標(biāo)準(zhǔn)）

——很好地完成了試題規(guī)定的任務(wù)；

——按要求寫出了內(nèi)容要點(diǎn)；

——語言結(jié)構(gòu)和詞匯選用恰當(dāng)、豐富；語言錯(cuò)誤極少；

——有效采用不同的連接手段，層次清楚；

——格式和語域恰當(dāng)；——完全達(dá)到與目標(biāo)讀者交流的目的。

附：（原標(biāo)準(zhǔn)對(duì)比）第五檔（很好）：

——完全完成了試題規(guī)定的任務(wù)。

——覆蓋所有內(nèi)容要點(diǎn)。

——應(yīng)用了較多的語法結(jié)構(gòu)和詞匯。

——語法結(jié)構(gòu)或詞匯方面有些許錯(cuò)誤，但為盡力使用較復(fù)雜結(jié)構(gòu)或較高級(jí)詞匯所致；具備較強(qiáng)的語言運(yùn)用能力。

——有效地使用了語句間的連接成分，使全文結(jié)構(gòu)緊湊。

——完全達(dá)到了預(yù)期的寫作目的。

其中最后兩項(xiàng)和原來的高考評(píng)分標(biāo)準(zhǔn)有著很大的區(qū)別，其要求進(jìn)一步明確：①?gòu)?qiáng)調(diào)格式和語域恰當(dāng)；②強(qiáng)調(diào)達(dá)到與目標(biāo)讀者交流的目的。而這其中＂語域＂的概念在中學(xué)階段英語教學(xué)中是個(gè)新鮮詞匯，第一次提到，并且明確列入評(píng)分標(biāo)準(zhǔn)之中。因此，了解其含義及要求，對(duì)于我們教師當(dāng)前如何有效指導(dǎo)學(xué)生的寫作就顯得尤為重要和迫切。那么，什么是語域呢？

二、語域的涵義

語域（register）：［(linguistics)range of vocabulary, grammar etc used by writers

in professional contexts.］是指根據(jù)語言使用的社會(huì)情景定義的一種具有某種具

體用途的語言變體，如科技語體、藝術(shù)語體、政論語體、公文語體等等。簡(jiǎn)言之，指在專業(yè)領(lǐng)域中作者所使用的詞匯，可以理解為與題目相關(guān)領(lǐng)域的vocabulary。＂

各語域的詞匯具有明確的語域功能＂（王玨,1999）。比方說：photograph與photo

均可指照片、圖片，但photograph是newspaperlanguage，屬于正式體，一般

常見于報(bào)刊雜志，而photo則是隨便體，使用較為自由，這主要是語域功能的差

異造成的。一般情況，法律、科技、報(bào)道，講演詞，政論文等都比較正式，而小

說中文體、語域最復(fù)雜，要視情況而定，不可一概而論。

三、語域的區(qū)別

語法正確的句子并不一定是好的句子，這其中牽涉到語域的因素?？陬^交際

時(shí)，當(dāng)然不要使用正式語體；同樣，書面交流時(shí)，千萬避免隨意語體。國(guó)內(nèi)（20

世紀(jì)80年代中后期交際教學(xué)法）教學(xué)改革前指摘學(xué)生的英語口語過于書面化；

教學(xué)改革后的情況又如何呢？批改學(xué)生的作文時(shí)，教師都有一種感覺：學(xué)生的作

文大多用詞簡(jiǎn)單、結(jié)構(gòu)松散，從語體角度分析，正式程度都較低，呈口語化的傾

向（蔡基剛2001：302）。

但是，目前中學(xué)英語寫作教學(xué)的寫作培訓(xùn)時(shí)間很少，有限的時(shí)間又多放在應(yīng)

試講評(píng)上，缺乏對(duì)語域等全局層次的特征傳授。學(xué)術(shù)英語（English for Academic

Purposes,EAP）研究專家Hyland博士曾指出，學(xué)生的絕大多數(shù)語篇語域知識(shí)是

通過在寫作中表達(dá)自己的思想獲得的(1998: 243)。什么是冷漠體，正式體，商量

體，隨便體，親密體，正式體，半正式體，公共體，半非正式體，非正式體等只

有在語篇環(huán)境或講話者的口吻中才能體會(huì)出來。不同的語域語言變體彼此是有區(qū)

別的，如果用幾個(gè)簡(jiǎn)單的例子來說明一下就會(huì)看得很清楚。如＂湯姆病了，今天

沒去上學(xué)＂，如果說Tom didn't go to school, because he was ill.這就是一句公共語，而如果說Tom was ill,so he didn't go to school.這就是口語體，即非正式語體，如

果說：Being ill ,Tom didn't go to school或Tom didn't go to school because of illness.都是正式語體(當(dāng)然這句話的內(nèi)容用這種句式表達(dá)并不合適)。從中我們可以看到

用原因從句的表達(dá)方式是比較正常的，用so連接的句子顯得不怎么正式，用抽

象名詞和分詞短語的形式都顯得十分正式。

另外有些表示相同意思的不同表示形式也有語域方面的區(qū)別。如according to

和in accordance with,前者為公共語，而后者為正式用語，It is important 和It is of

importance相比，也是前者為公共語，而后者為正式體。甚至連冠詞的用法都可

以表示這種區(qū)別，The horse is a useful animal;A horse is a useful animal;Horses are

useful animals。第一種用定冠詞加單數(shù)名詞表示類屬的是正式用法，而用不定冠

詞加單數(shù)名詞表示類屬的則為公共語，最后一種，復(fù)數(shù)泛指的類屬表示法則為非

正式語體。

所以，我們?cè)趯W(xué)生英語寫作之初時(shí)，引導(dǎo)他們弄清所寫文章的語域情況是十

分重要的，因?yàn)檫@將決定我們?cè)趯懽鲿r(shí)如何選詞組句，可謂＂看菜吃飯，量體裁

衣＂。例如：我們?cè)趯懸黄斡洉r(shí)要用到下面一個(gè)句子：＂一小時(shí)后，我們終于

登上高達(dá)海拔1296公尺的衡山之巔祝融峰。＂可譯為：After an hour of climbing,we finally found ourselves at zhurong Peak, the very apex of Mt, Hengshan, towering

1,296m above the sea level.我們可以從after……climbing這種動(dòng)名詞用法看出比

較正式，它不是用短句表示(After we had climbed for an hour)，如用短句則顯得更

為常見的公共語體，另外，apex，頂峰，巔峰，與之同義的詞還有summit, top

等詞，但apex更為典雅，正式程度高于summit，更高于top.再有towering這一分詞的使用，也說明其正式性，不是用短句(it towers

1,296m above sea level)。那么，我們?cè)诜g這句時(shí)則用了比較正式的語言。但如

果我們是在記錄人們交談中聽到下面這樣一些簡(jiǎn)短而連續(xù)句子：＂我們爬了一個(gè)

鐘頭，終于到了祝融峰的山頂，它是衡山的最高峰，有1296公尺＂則譯為這樣

較合適：After we had climbed for an hour，we finally found ourselves at zhurongPeak.This is the very top of Mt, Hengshan and it towers 1,296 meters above sea level.這就是語域決定作用的初步體驗(yàn)。

四、語域使用應(yīng)遵循的要求

在語言是否達(dá)到與目標(biāo)讀者交流的目的的制約下，寫作中語域的使用應(yīng)遵循

以下要求：

（一）合乎規(guī)范

事物、現(xiàn)象之間的相似性、相關(guān)性和相通性是詞語跨域使用產(chǎn)生的基礎(chǔ)，事

物和現(xiàn)象之間的這些關(guān)系使人們可以通過比喻、借代、引申的手法進(jìn)行表達(dá)。

如：＂bug＂一詞譯成漢語＂臭蟲＂。其電腦術(shù)語義指＂系統(tǒng)、設(shè)備或程序中的一種錯(cuò)誤或故障＂。＂臭蟲＂獲其殊榮完全是因?yàn)樯_電腦科研人員晚上工作，遭人痛恨而得。這就要求人們?cè)谶x擇詞語時(shí)，注意使用詞語中最具普遍性的意義。

要多模仿原汁原味的精美句型、短文，使用比喻、借代、典故等不能生搬硬套，必須理解其文化背景，適應(yīng)交際的需要，符合詞語規(guī)范化的原則，才能避免

chinglish的。

即coherence（being(of ideas, thoughts, speech, reasoning, etc)connected

logically or consistently;easy to understand;clear.）連貫性，一致性?？梢岳斫鉃?/p>

觀念、思想、言論、推理等表達(dá)準(zhǔn)確、合乎邏輯；前后一致；讓人易懂。這就要

求寫作時(shí)明確試題規(guī)定的任務(wù)，準(zhǔn)確貼切地選擇詞語有效地表達(dá)事物的概念和人的思想情感。如不能準(zhǔn)確地理解詞語的詞義就去跨域使用，必將會(huì)出現(xiàn)詞不達(dá)義、張冠李戴的現(xiàn)象，達(dá)不到指稱事物和目標(biāo)讀者交際的目的。如要表達(dá)的是演講稿、發(fā)言稿，則語言必須符合口語習(xí)慣，隨意體較為受歡迎，如果過多地采用正式體則顯得教條、呆板，缺乏應(yīng)有的生機(jī)活力，語言也就沒有感染力。如：為了幫助學(xué)生認(rèn)識(shí)到因果關(guān)系表達(dá)的豐富性及其文體差別，減少過分依賴死記硬背常用范式的熟悉度，我們從原因表達(dá)用詞because等其它因果標(biāo)記（諸如as，since與for，以及復(fù)合介詞類（because of/as a result of等）、名詞類（cause/reason等）、介詞（with/through/by等）、動(dòng)詞類（cause/result in/contribute to等）的語料的掌握上，應(yīng)該提供給學(xué)生足夠的語境練習(xí)以強(qiáng)化域語知識(shí)的掌握。

例如：I am not able to watch TV, because I live in school.（逗號(hào)顯示非正式的特征）→I cannot watch TV because my dorm has no TV set.用since, for表共享原因可能更好，因?yàn)楸揪渲攸c(diǎn)說明我無法看到電視，進(jìn)而為以后闡釋自己對(duì)外界知識(shí)了解不多提供立論基礎(chǔ)；但作者提供的原因并不直接，他所認(rèn)為的共享知識(shí)-＂學(xué)校宿舍沒有電視＂并非一定共享。另外，be able to 指'能力'，實(shí)際上作者想表達(dá)'不可能'-cannot。

（三）避免濫用

即cohesion（tendency to stick together.）凝聚力。凝聚力，可以理解為圍繞一個(gè)中心展開討論，思路清晰，支持有力，不寫與題目無關(guān)的東西。為追求新奇、標(biāo)新立異或故作高深，有人不顧是否達(dá)到與目標(biāo)讀者交流的目的，把詞語跨域使用作為一種新穎、超常的言語方式大加運(yùn)用，必將適得其反。中國(guó)學(xué)生易受發(fā)展性因素和漢語負(fù)遷移的影響，過分依賴于漢語運(yùn)用的感覺且表現(xiàn)出明顯的口語化現(xiàn)象，偏離了原汁原味英語語篇運(yùn)用的常規(guī)。因此，作為學(xué)生在英語學(xué)習(xí)過程中，要多分析語言現(xiàn)象，注意詞匯句型的語域功能，多積累，多感知，多體會(huì)，方能為寫出好文章打下堅(jiān)實(shí)的基礎(chǔ)。

總之，只有充分理解語域的內(nèi)涵及其功能特點(diǎn)，才能把握好高中英語課程標(biāo)準(zhǔn)對(duì)中學(xué)寫作的新要求，才能寫出內(nèi)容充實(shí)、要點(diǎn)全面、語言豐富、文字優(yōu)美、行文連貫、過渡自然、表達(dá)地道、語域恰當(dāng)?shù)暮梦恼?，才能完全達(dá)到與目標(biāo)讀者交流的目的，也才能很好地完成試題規(guī)定的任務(wù)，取得理想的高分。

參考書目：

1.普通高中《英語課程標(biāo)準(zhǔn)》（人民教育出版社2003年4月第一版）

2.2003年高考英語試卷及答案(天津卷)掃描版評(píng)分標(biāo)準(zhǔn)（人民網(wǎng)）

3.《英語翻譯課程學(xué)習(xí)方法》凡夫著

4.《對(duì)于雅思考試寫作評(píng)分標(biāo)準(zhǔn)的解析》賴勁松著

第四篇：機(jī)三信息員論文

人人都是通風(fēng)員

將理念引深到班子建設(shè)，從決策中堵塞安全隱患漏洞。實(shí)現(xiàn)安全管理科學(xué)化，領(lǐng)導(dǎo)班子建設(shè)是核心。只有領(lǐng)導(dǎo)班子樹立以人為本，安全發(fā)展的科學(xué)發(fā)展觀，落實(shí)正確的政績(jī)觀和業(yè)績(jī)觀，進(jìn)一步加強(qiáng)對(duì)安全工作的領(lǐng)導(dǎo)，強(qiáng)化安全責(zé)任意識(shí)和安全工作敏感性，才能促進(jìn)企業(yè)安全發(fā)展。將“人人都是通風(fēng)員”理念引深到班子建設(shè)，就是要高度重視并能以這一理念統(tǒng)領(lǐng)安全工作。采取會(huì)議、座談、討論、溝通等多種形式來統(tǒng)一班子成員的思想，形成“安全是企業(yè)安全發(fā)展的前提與保障”的共識(shí)。從而在全礦的安全工作上做到了思想統(tǒng)一、步調(diào)一致，能夠不折不扣地把各個(gè)時(shí)期上級(jí)對(duì)安全工作的指示精神和要求落實(shí)到日常的安全工作當(dāng)中。就是要進(jìn)一步明確各級(jí)領(lǐng)導(dǎo)干部“人人都是通風(fēng)管理員”責(zé)任，站在更高的角度落實(shí)“人人都是通風(fēng)員”安全理念，做好安全管理工作。特別是安全管理的決策中，決不能拍腦門、拍胸脯，必須冷靜思考，多聽取周圍同志的意見，明確工作思路，做出英明的決策。各級(jí)領(lǐng)導(dǎo)班子要進(jìn)一步轉(zhuǎn)變作風(fēng)，狠抓落實(shí)，從根本上提高控制效能，加強(qiáng)和完善安全管理體系建設(shè)，嚴(yán)格落實(shí)安全生產(chǎn)責(zé)任制和各項(xiàng)安全生產(chǎn)管理制度。要經(jīng)常分析研究安全生產(chǎn)狀況，深入把握安全生產(chǎn)的規(guī)律和特點(diǎn)，抓緊解決安全生產(chǎn)中的矛盾和問題，針對(duì)性地制定和強(qiáng)化安全

生產(chǎn)的制度、措施，使生產(chǎn)過程中各種事故風(fēng)險(xiǎn)和傷害因素始終處于有效控制狀態(tài)。

將理念引深到安全培訓(xùn)，不斷提高員工安全素質(zhì)。實(shí)現(xiàn)安全管理科學(xué)化做好員工培訓(xùn)是基礎(chǔ)。安全生產(chǎn)作業(yè)過程中，人的不安全行為是誘發(fā)事故的主要原因，員工的安全意識(shí)和業(yè)務(wù)素質(zhì)成為避免事故的重要因素。將“人人都是通風(fēng)員”理念引深到安全培訓(xùn)，就是要通過多種形式，多種渠道搞好員工日常安全培訓(xùn)工作。采取實(shí)地走避災(zāi)路線、現(xiàn)場(chǎng)說法等各種便于職工接受的方法，深入推進(jìn)“人人都是通風(fēng)員”安全理念和安全應(yīng)知應(yīng)會(huì)知識(shí)的貫徹落實(shí)，把學(xué)習(xí)“一通三防”知識(shí)同員工的崗位特點(diǎn)相結(jié)合，把學(xué)習(xí)“一通三防”知識(shí)與“三違”人員的教育相結(jié)合，把學(xué)習(xí)“一通三防”知識(shí)與案例分析相結(jié)合，把學(xué)習(xí)“一通三防”知識(shí)與演示實(shí)驗(yàn)和井下學(xué)習(xí)相結(jié)合，確保培訓(xùn)效果，提高員工的實(shí)際操作能力和自保能力。隨著“人人都是通風(fēng)”安全理念的不斷深化，這一理念的內(nèi)涵將牢牢地扎根在每一位員工的心上，使員工現(xiàn)場(chǎng)的應(yīng)急思維實(shí)現(xiàn)本質(zhì)安全化，有效提高煤礦的安全管理層次，為企業(yè)穩(wěn)步、高效、健康、持久地向前發(fā)展，提供可靠的安全保證。

將理念引深到現(xiàn)場(chǎng)管理，從源頭控制事故的發(fā)生。實(shí)現(xiàn)安全管理科學(xué)化，現(xiàn)場(chǎng)是重點(diǎn)。安全工作的源頭在現(xiàn)場(chǎng)，安全工作的重點(diǎn)在現(xiàn)場(chǎng)?！叭巳硕际峭L(fēng)員”的引深也必須在

現(xiàn)場(chǎng)、在崗位。要以“想、看、干、管”為要決，真正做到干部指揮到位、隱患排查到位、環(huán)境監(jiān)控到位，實(shí)現(xiàn)從源頭控制事故、杜絕事故發(fā)生。安全工作有指標(biāo)不是高水平，安全目標(biāo)為零才是真水平。實(shí)現(xiàn)安全事故為零的目標(biāo)，就是要求各級(jí)領(lǐng)導(dǎo)干部要深入井下，盯住現(xiàn)場(chǎng)，盯班上崗，盯住不安全隱患，盯住不放心的人和事，消除人的不安全行為和物的不安全狀態(tài)，從現(xiàn)場(chǎng)這個(gè)生產(chǎn)源頭上保障安全生產(chǎn)。同時(shí)要狠抓質(zhì)量標(biāo)準(zhǔn)化管理，從基層、基礎(chǔ)抓起，從現(xiàn)場(chǎng)抓起，從崗位抓起，大力開展標(biāo)準(zhǔn)崗、精品崗創(chuàng)建活動(dòng)，將“人人都是通風(fēng)員”的“三懂三會(huì)三做到”崗位標(biāo)準(zhǔn)融入標(biāo)準(zhǔn)崗、精品崗建設(shè)中，在生產(chǎn)過程中每個(gè)環(huán)節(jié)、每道工序、每個(gè)崗位的現(xiàn)場(chǎng)管理上落實(shí)“人人都是通風(fēng)員”崗位標(biāo)準(zhǔn)，規(guī)范工作流程、作業(yè)流程和操作流程，規(guī)范崗位人員的現(xiàn)場(chǎng)操作行為。

引深“人人都是通風(fēng)員”理念保證一流礦井建設(shè)順利進(jìn)行的有效途徑，是建設(shè)企業(yè)文化的有效手段，是優(yōu)秀領(lǐng)導(dǎo)班子的具體體現(xiàn)，是本質(zhì)安全礦井建設(shè)的基礎(chǔ)，為創(chuàng)新管理模式提供了新思路，是爭(zhēng)創(chuàng)成功企業(yè)的先決條件。我們一定要遵循事物發(fā)展的規(guī)律，牢固樹立“安全責(zé)任重于泰山”思想，深刻把握和積極實(shí)踐理念，始終把安全管理擺在企業(yè)管理和生產(chǎn)全過程的首位。確保企業(yè)穩(wěn)步、健康、有序地向前發(fā)展，確保安全生產(chǎn)長(zhǎng)治久安。

人人都是通風(fēng)員

一條理念管百年

第五篇：英文論文演講稿

篇一：英語論文展示演講稿

1、hello everyone！today i will introduce you a paper, which is called “effects of corporate governance on capital structure: empirical evidence from pakistan “

2、i will use the following four parts to introduce

3、i got this paper from the emerald reprints the world’s leading publisher of management research and the type of the paper is research paper 納迪姆阿麥的sheke

4、then we can have a simple knowledge of the two authors:nadeem ahmed sheikh and 王宗軍 one is a doctoral degree candidate in the school of management, hua zhong university of science and technology, wuhan.the other is a professor in this college 5.about the paper’s outline firstly the aim of this empirical study is to investigate whether corporate governance attributes affect capital structure choices of pakistani firms then the design of the paper is multiple regression analysis

6、in order to have a good knowledge of the paper we can from the following three aspects to the attributes of the corporate governance are background also includes ：measures of corporate governance and their relation to capital structure

8、research design firstly 1.research methodology：it includes three aspects: data variables and methodology date: this study investigates the significant corporate governance attributes that may affect the capital structure of non-financial firms listed on the karachi stock exchange pakistan during 2004-2008.and the final sample set consists of 775 observations for 155 firms over a period of five years.this study employed panel data methodology(面板數(shù)據(jù)方式)because sample contained data across firms and over time

9、this table is the definition of variables.it includes three parts: 10.dependent variables consist of total debt ratio and long-term debt ratio.this is a basic formula.12、this table is the yearly mean value of shareholding pattern

13、here are some of regression analysis tables, through the multiple regression analysis the paper gives the conclusions

14、the results is as follows: capital structure is positively related to board size、outside directors and ownership concentration.that is to say: a large board serve as a means to obtain support from external environment;boards with more independent directors can take on more debt on favorable terms due to effective monitoring;block holders have more ability than dispersed shareholders to force management to take those actions that maximize the shareholder wealth.15、on the other hand, capital structure is negative related to managerial ownership、director remuneration、profitability and liquidity.16、in the end, i have a summary: the results of the paper indicate that corporate governance attributes, in part, explicate the financing behavior of pakistani firms and, the empirical results of this study provide support to corporate managers in establishing an optimal capital structure, and to regulatory authorities for enacting laws and developing institutional support to make corporate governance mechanisms work more effectively in the country.17、thats all, thank you for listen to me, if you are interested in this paper you can have a study after class thank you!篇二：英語論文演講稿

my paper is revenge tragedy in english renaissance——about 《hamlet》 ppt1:....ppt2:....ppt3:....ppt4:next, let`s analyse the relationship between the characters in the drama.this is a relationship diagram.hamlet ,the prince of denmark and also the protagonist(主角、主要人物、領(lǐng)導(dǎo)者）was about thirty years old at the start of the play.hamlet is the son of queen gertrude and the late king hamlet, and the nephew of the present king, claudius.hamlet is melancholy, bitter, and cynical, full of hatred for his uncle’s scheming and disgust for his mother’s sexuality.a reflective and thoughtful young man who has studied at the university of wittenberg, hamlet is often indecisive and hesitant, but at other times prone to rash and impulsive acts.哈姆雷特 prince hamlet —— 丹麥王子。為父王的鬼魂所困擾，要對(duì)殺父兇手復(fù)仇。經(jīng)歷了痛苦的掙扎之后他達(dá)成了目的，整個(gè)王宮也陷入了死亡的恐怖之中。他最后也中了致命的毒劍死去。

claudius, as the king of denmark, hamlet’s uncle and the villain（反派角色）of the play, was a calculating, ambitious politician,and was driven by his sexual appetites and his lust for power, but he occasionally showed signs of guilt and human feeling—his love for gertrude, for instance, seems sincere.克勞迪斯 claudius —— 丹麥現(xiàn)任國(guó)王。他是哈姆雷特的叔父，在哥哥死后繼任了王位。老國(guó)王的鬼魂告訴哈姆雷特，他正是謀殺自己的兇手。他罪有應(yīng)得，最后死在侄子復(fù)仇的毒劍下。

鬼魂 king hamlet(ghost)—— 哈姆雷特的父親死后化成的鬼魂。他被弟弟毒死時(shí)，哈姆雷特正在國(guó)外。

ophelia-polonius’s daughter, a beautiful young woman with whom hamlet has been in love.ophelia is a sweet and innocent young girl, who obeys her father and her brother, laertes.dependent on men to tell her how to behave, she gives in to polonius’s schemes（詭計(jì)）to spy（偵察）on hamlet.even in her lapse into（陷入）madness and death, she remains maiden, singing songs about flowers and finally drowning in the river。

歐菲莉 ophelia—— 波洛涅斯的女兒。她與哈姆雷特雙雙陷入愛河，但種種阻力警告王子，政治地位使他們無望結(jié)合。作為哈姆雷特瘋狂復(fù)仇計(jì)劃的一部分，她被他無情拋棄，加上父親的死讓她陷入精神錯(cuò)亂，最終失足落水溺斃。

ppt6: then let`s look at the character analysis of hamlet.hamlet pretended to be mad in order to revenge.he also use his intelligence to approve his uncle`s guilt.when hamlet confirmed that claudius was guilt, he decided to revenge without fear.then he also use stratagem to make himself avoid being killed.all of these approved that he was brave and smart.ppt7: he pursued ophelia and finally gave up because of the revenge.before he was fight with laertes, he said sorry to him.this indicates he was guilt and sorry for laertes because it was he that made laertes lose his father.these approved that he was a kind and sincere man.ppt8:.....ppt9: when we read the play, we can also easily feel the dilemma.just like the words “to be or not to be-that is the question” ppt10:.....ppt11:......篇三：如何寫好英文演講稿

淘寶專業(yè)編制 id:文章團(tuán)購(gòu)網(wǎng)

如何寫好英文演講稿

從很多方面來說，寫演講稿就像寫論文，但演講稿卻沒有像論文那般特別注重單詞的拼寫與標(biāo)點(diǎn)的錯(cuò)誤。寫演講稿的時(shí)候，不要用一些發(fā)音不順暢或是你不明白意思的單詞，因?yàn)闀?huì)導(dǎo)致你的演講不夠流暢。instructions 說明

1.assess how much time your speech should take.if you dont have a time limit, try to keep your speech brief yet informative.估算自己演講所需的時(shí)間。如果沒有演講上的時(shí)間限制，就盡量讓你的演講篇幅簡(jiǎn)短且內(nèi)容豐富。

2.think about your audience and let your perception of the audience shape the tone of your speech as you write it.站在聽眾的角度多想想，當(dāng)你撰寫演講稿時(shí)，你要讓觀眾也能在演講稿中切身體會(huì)你的演講魅力。

3.begin with an introduction that establishes who you are, what your purpose is, what youll be talking about and how long youre going to take.you may want to include a joke, anecdote or interesting fact to grab the audiences attention.先介紹自己，以表述演講目的、演講主題和演講時(shí)長(zhǎng)作為開端。在這段話中，你要說一個(gè)笑話、奇聞奇事或趣事來直接引起聽眾的注意。

4.organize your information into three to seven main points and prioritize them according to importance and effectiveness.用3-7條大綱組織演講內(nèi)容信息，并根據(jù)重要性和有效性分清要點(diǎn)主次。

5.delete points that arent crucial to your speech if you have too many for your time frame.假如時(shí)間不允許，你可以刪減一些演講中不重要的點(diǎn)。

6.start with your most important point, then go to your least important point and move slowly back toward the most important.for example, if you have five points with no.5 being the most important and no.1 being the least important, your presentation order would be 淘寶專業(yè)編制 id:文章團(tuán)購(gòu)網(wǎng)

5-1-2-3-4.從最重要的一點(diǎn)開始你的演講，之后到次重要點(diǎn)，然后再慢慢回到最重要點(diǎn)上。例如，你的演講稿中有5點(diǎn)要講，第5點(diǎn)是其中的重中之重，而第1點(diǎn)是次重要點(diǎn)，你的演講順序應(yīng)為：51234。7.add support to each point using statistics, facts, examples, anecdotes, quotations or other supporting material.借助圖表、事實(shí)、例子、奇聞?shì)W事、引文與其它材料作為演講點(diǎn)的支撐部分。

8.link your introduction, points and conclusions together with smooth transitions.引言、演講要點(diǎn)和結(jié)論連貫順承地串在一起。

9.write a conclusion that summarizes each of your points, restates your main purpose and leaves the audience with a lasting impression.用結(jié)論總結(jié)所有演講點(diǎn)，重申主題，讓觀眾留下最后的深刻印象。