外文翻译

Introduction

Cement studies range from the individual analysis of each of the component phases,to research into highly complex systems with all their variables.Joint studies of Portland clinker components and their interaction with the gypsum(CaSO4×2H2O)added to regulate set-ting time,for instance,have found that:

?The C3A and C4AF in ordinary Portland cement compete for gypsum,but as it is more reactive,C3A consumes higher quantities of the addition more rap-idly.This,in conjunction with constraints on the amount of gypsum used to ensure that only the set-ting time is regulated,leads to the formation of less ettringite than might otherwise be expected[1].?Gypsum also accelerates the hydration rate of cal-cium silicates,which likewise compete for sulphate ions during hydration,given the significant amount of sulphates included in the CSH gel.The inclusion of2 to6%of gypsum has been found to accelerate alite hydration,and from2to4%,belite hydration[2].

A high gypsum content contributes to the forma-tion of large amounts of ettringite,however,which re-tards paste setting and hardening and prompts sub-stantial changes in volume as a result of micro-

structural expansion and cracking;a low gypsum con-tent,in turn,favours the formation of monosulpho-aluminate solid solutions before the end of the latent period of C3S hydration,thereby retarding the accel-eration period of this compound[1].

The study of mineral pozzolanic additions has also developed from the analysis of discrete sys-tems[3–5].In the case of silica fume,which is a highly pozzolanic addition,it has been found that:?After three days,at addition rates of5and10%,C3A hydration is retarded[6].

?Additions of5–10%accelerate alite hydration up to the age of28days[6,7].

?Lastly,including the addition also heightens the hydration rate of b C2S during the first28days[8].

The outcome of all the foregoing is to produce greater heat of hydration at early ages[9],an effect that grows more intense as the percentage of the addi-tion is raised from5to10%[10].The high BET spe-cific surface of silica fume has been identified as the cause of its over-stimulation of Portland cement hydration reactions[11].In addition,however,an in-direct stimulatory effect on such reactions has been attributed to the substance,due to the fixation of cal-Journal of Thermal Analysis and Calorimetry,Vol.87(2007)2,331–336

CALORIMETRY OF PORTLAND CEMENT WITH SILICA FUME AND GYPSUM ADDITIONS

V.Rahhal1*,O.Cabrera1,R.Talero2and A.Delgado2

1Civil Engineering Department,Faculty of Engineering,UNCPBA,Avda.del Valle5737,(B7400JWI)Olavarría,Argentina

2Eduardo Torroja Institute for Construction Science,CSIC,Serrano Galvache no4,28033Madrid,Spain

The use of active mineral additions is an important alternative in concrete design.Such use is not always appropriate,however,be-cause the heat released during hydration reactions may on occasion affect the quality of the resulting concrete and,ultimately,struc-tural durability.The effect of adding up to20%silica fume on two ordinary Portland cements with very different mineralogical com-positions is analyzed in the present paper.Excess gypsum was added in amounts such that its percentage by mass of SO3came to7.0%.

The chief techniques used in this study were heat conduction calorimetry and the Frattini test,supplemented with the determi-nation of setting times and X-ray diffraction.The results obtained showed that replacing up to20%of Portland cement with silica fume affected the rheology of the cement paste,measured in terms of water demand for normal consistency and setting times;the magnitude and direction of these effects depended on the mineralogical composition of the clinker.Hydration reactions were also observed be stimulated by silica fume,both directly and indirectly–the latter as a result of the early and very substantial pozzolanic activity of the addition and the former because of its morphology(tiny spheres)and large BET specific surface.This translated into such a significant rise in the amounts of total heat of hydration released per gram of Portland cement at early ages,that silica fume may be regarded in some cases to cause a synergistic calorific effect with the concomitant risk of hairline cracking.The addition of excess gypsum,in turn,while prompting and attenuation of the calorimetric pattern of the resulting pastes in all cases,caused the Portland cement to generate greater heat of hydration per gram,particularly in the case of Portland cement with a high C3A content.

Keywords:gypsum,heat of hydration,Portland cements,pozzolanicity,silica fume

*Author for correspondence:vrahhal@https://www.wendangku.net/doc/8013148809.html,.ar

cium hydroxide in the pozzolanic reaction from the earliest ages[12].On the one hand,the pozzolanic re-action has been confirmed to take place even in the first few days,chiefly on the grounds of the consump-tion of Ca2+ions in the liquid phase,but also of the uptake–in descending order–of OH–and K+ions [13–17].And on the other,the amount of heat re-leased per gram of Portland cement in pastes with sil-ica fume has been found to amply exceed the amount of heat released by the respective plain pastes[18]. Experimental

Objective

In light of these considerations on substances such as gypsum and silica fume;the objective or purpose of the present study is,to analyze their overall effect on the hydration of two Portland cements with widely varying compositions,with a view to limiting their use in high performance concrete.

Materials and methods

Two Portland cements with widely differing mineral-ogical compositions were chosen for this study.One, with a very high C3A content,called PC1,and the other,with a minimum C3A content(<1%)and a max-imum C3S content,called PC2;the other constituents were a very active pozzolanic mineral addition(silica fume,SF)and rich ground natural gypsum.Distilled water was used in the mortar in all cases.

The chemical composition,density and BET spe-cific surface of the Portland cements and the addition are given in Table1.The potential composition of the Portland cements found from their chemical composi-tion and the Bogue equations was as follows:51%C3S, 16%C2S,14%C3A and5%C4AF for PC1and 79%C3S,2%C2S,0%C3A and10%C4AF for PC2.

The different chemical and mineralogical com-positions of the two cements Portland are partly re-flected in the difference in their densities;their fine-ness,on the contrary,is comparable.SF contains: over90%SiO2,88.46%SiO

2

r–(reactive sil-ica)[19,20]and yet has a much lower density than quartz(2.70)and a very high specific surface.Its diffractogram,shown in Fig.1,reveals the presence of cristobalite(C);the diffuse pattern is indicative of the substance’s primarily vitreous nature[21].

The pastes for the study were made by mixing each Portland cement separately with SF,in percent-ages by mass of90/10and80/20,in the absence of gypsum or with sufficient amounts to bring the total SO3content to7.0%.Table2gives the setting times and water demand for500-g samples.These two physical parameters were determined as laid down in European standard EN196,part3[22].

It may be deduced from Table2that particle size and morphology had a significant effect on water de-mand.The SF spheres separated the Portland cement particles,making a greater surface area available for hydration.Moreover,given its density and specific surface,the silica fume comprised a larger number of particles than the Portland cement replaced,signifi-cantly increasing the water demand.

Pozzolanic activity was evaluated chemically by Frattini’s test[23],by comparing the amount of calcium hydroxide in an aqueous solution covering the hydrated sample at40oC for a given period of time(in this case,48h),with the solubility isotherm for calcium hy-droxide in an alkaline solution at the same temperature. The indication of pozzolanic activity was defined to a lower calcium hydroxide concentration in the sample solution than on the solubility isotherm,due to its up-take in the pozzolanic reaction(=+result)(Fig.2).

RAHHAL et al

.

Fig.1XRD pattern of the SF Table1Chemical composition of cementing materials

The heat release pattern was ascertained by heat

conduction calorimetry for pastes.Measurements

were taken at a temperature of 25oC.Data were re-

corded during the first 48h of hydration and the total

heat released was computed by integrating the area

under the rate of release-age curve.This methodology

is widely used to monitor hydration in pure Portland

cement [1]as well as for cements containing mineral

additions [24].To obtain equally workable pastes,the

water:cementitious material ratios used were 0.5for

pure Portland cements,0.625for mixes with 10%SF

and 0.75for mixes with 20%silica fume.

Results and discussion

Figure 2shows [OH –]and [CaO]determined at 48h.

Note that the pastes with SF showed pozzolanic activ-

ity at 48h (i.e.,6days before its first specified age,

8days [25]),in the case of PC1at (addition-cement)

replacement rates of 10%,and in PC2at rates of 15%

or higher.Some of these mixes failed to show pozzo-

lanicity at that age because the rate of the hydration

reaction was so high that it could not be countered or

compensated for by the fixation of the calcium hy-

droxide resulting from the pozzolanic reaction.

When gypsum was added to the samples,the

[CaO]increased due to its partial dissolution in water,

whereas [OH –]declined,partially because of the ef-

fect dilution of the Portland cement,although no

pozzolanic activity was detected in any of the samples

within the first 48h.

Figures 3and 4show the first 48-h calorimetric

curves for the samples containing PC1and PC2,re-

spectively.The first stage or induction period for

plain PC1,visible in Fig.3,shows a high rate of heat

release due to initial hydrolysis and the hydration of

the aluminous phase (primarily C 3A);the rate

dropped to 0.91W kg –1after 2h,accounting for the

first trough on the calorimetric curve.This was fol-lowed by the acceleration of hydration reac-tions –with the initial precipitation of the CSH gel,primarily from C 3S –,until the rate of heat release peaked for a second time at 2.97W kg –1at reaction time 11:12.During acceleration,PC1began to set (Table 2).Thereafter the rate of the hydration reac-tions declined through the 13th hour,overlapping in this stage with the aluminous phase transformation re-actions,which take place when the SO 3/Al 2O 3molar ratio falls to under 3(in this case,0.69).But the most prominent effect of the reaction was the enormous amount of heat released,which rose to 3.33W kg –1,forming the third peak on the calorimetric curve,17h and 24min into the reaction.Finally,the hydration re-actions slowed to and remained at a low rate.The test was considered completed after 48h,taking the reading at that time as the third trough on the calorimetric curve.Although when 10and 20%SF was added to the PC1the calorimetric phases or stages observed were es-sentially the same as for the plain PC1,certain differ-ences were noted.During the first stage,for instance (from t =0to the first trough),the effect of the SF parti-cles was to dilute the Portland cement,with rates of 0.83and 0.88W kg –1,respectively.At the same time,how-ever,the hydration reactions were enhanced in the frac-tion of the PC1with which they were mixed,given that the first trough appeared earlier than in plain PC1(1:36and 1:42h,respectively).This was followed by the ac-celeration of the hydration reactions –with the initial formation,in this case,of gels of chiefly C 3S and SF ori-gin and silanol groups of SF origin –with the second trough recorded at reaction times of 10:12and 7:54,re-spectively.That is to say,both minima appeared earlier than in plain PC1,and the interval between the first and second troughs was narrower with both 10and 20%re-placement rates.This confirmed that the hydration reac-tion was stimulated by the SF,an effect that was further corroborated by the higher rate of heat release values PORTLAND CEMENT WITH SILICA FUME AND GYPSUM

ADDITIONS

Fig.2Pozzolanicity (Frattini test)at 48h:

results

Fig.3Calorimetric curves for mixes with PC1

(3.92and 4.11W kg –1)found for the mixes than for

plain PC1.Subsequently,the low SO 3/Al 2O 3molar ra-

tios in the two cement mixes (0.68and 0.67,respec-

tively)prompted aluminous phase transformation.The

outcome was third peak reaction times of 14:24

and 11:34,respectively,for 10and 20%replacement,

both higher than for plain PC1.Moreover,the rate val-

ues at these third peaks were 4.77and 8.20W kg –1–

higher than for plain PC1–,again providing dual confir-

mation (troughs appearing in shorter times and higher

heat of hydration release values)of hydration stimula-

tion as a result of replacing PC1with SF.

In short,the first troughs on the heat release

curves for the samples containing PC1appeared ear-

lier and were attenuated for all mixes,and the second

and third peaks appeared earlier for all mixes and

their intensities were higher than in plain PC1.

When gypsum was added to the PC1,the calori-

metric curve was substantially attenuated and the

third peak disappeared;when gypsum was included in

the SF –PC1/SF mixes –,in turn,all the curves were

slightly retarded and the first trough and second peak

were slightly attenuated.As in the case of plain PC1,

the third peak disappeared altogether.

The first stage or induction period for plain PC2,

visible in Fig.4,is also characterized by a high rate of

heat release due to initial hydrolysis;after 1:37h,the

rate dropped to 0.64W kg –1,accounting for the first

trough on the calorimetric curve.This was followed

by the acceleration of hydration reactions –with ini-

tial precipitation,this time at a higher rate,of the CSH

gel,primarily from the C 3S –,up to a second heat re-

lease rate peak of 3.25W kg –1,reached at 7:39h (the

fact that this value was higher than for PC1confirmed

that PC2had a higher C 3S content).PC2also began to

set during acceleration (Table 2).The reactions

slowed thereafter and although hydration continued,

the rate remained low.The test was considered com-

pleted after 48h,taking the reading at that time as the

second trough on the calorimetric curve.In this case,there was no transformation of the aluminous phase,since the C 3A content in PC2was nil,virtually.Although when 10and 20%SF was added to the PC2the calorimetric phases or stages observed were essentially the same as for the plain PC2,certain dif-ferences were noted.During the first stage,for in-stance (from time=0to the first trough),the effect of the SF particles was to dilute the PC2,with rates of 0.27and 0.26W kg –1,respectively.Moreover,the hydration reactions were observed retarded,with the troughs appearing at reaction times of 2:27and 1:51,respectively.The hydration taking place between the first trough and the second peak lasted longer,with the second peak appearing at 9:24and 8:55,respec-tively,for 10and 20%replacement:i.e.,not only later than in the case of PC2,but with a longer interval be-tween the first trough and the second peak.The time lapsing between initial and end setting times was also longer and final setting was retarded in all these pastes.And yet,in this stage also,SF was observed to stimulate the hydration reactions in the fraction of the Portland cement with which it was mixed,with rates of release at the second peak equal to and greater than (2.92and 2.84W kg –1),respectively,the proportional

rate for PC2(2.92and 2.60W kg –1).For the same rea-

RAHHAL et al .

Table 2Times of setting and normal consistency Cements

Setting times (h:m)Normal consistency/%initial final PC1,without 7.0%SO 3PC1,with 7.0%SO 3PC1/SF 90/10,without 7.0%SO 3PC1/SF 90/10,with 7.0%SO 3PC1/SF 80/20,without 7.0%SO 3PC1/SF 80/20,with 7.0%SO 3

3:203:351:402:200:350:505:106:154:104:453:554:3531323635.74543.5PC2,without 7.0%SO 3PC2,with 7.0%SO 3PC2/SF 90/10,without 7.0%SO 3PC2/SF 90/10,with 7.0%SO 3PC2/SF 80/20,without 7.0%SO 3PC2/SF 80/20,with 7.0%SO 34:304:154:455:003:303:406:156:108:558:559:209:4528283635.44446.2Fig.4Calorimetric curves for mixes with PC2

son as in the case of plain PC2,the third stage(trans-formation of the aluminous phase)was absent.

In short,both the first trough and the second peak were retarded and attenuated in all the mixes, and although stimulation was observed,it was much less pronounced than for mixed cements containing PC1.This is an unequivocal sign that the higher C3A content in the latter is a determining factor in the en-hanced stimulation of the hydration reaction.

Adding gypsum to PC2significantly attenuated and retarded the first trough and second peak with re-spect to plain Portland cement.Similarly,adding gyp-sum to the mixes retarded the first trough and the sec-ond peak and widened the interval between the two.

The percentage of total heat of hydration re-leased per gram of Portland cement after48h is shown in Fig.5.It will be noted that both the nature of the additions and the composition of the cements af-fected mix behaviour,as did the presence or absence of gypsum up to an SO3content of7.0%.

Silica fume,at percentages of both10and20%, produced mixes that generated greater heat of hydration with PC1than with PC2.This behaviour can be ex-plained by the composition of the Portland cements used.The high C3A content in PC1naturally produced more heat of hydration at the early ages.After48h of hydration,SF indirectly prompted the respective frac-tion of the PC with which it was mixed to generate a larger amount of heat of hydration than the plain PC. (This involved direct stimulation of hydration via the in-ternal and external humidification of each particle from the time the mixing water was initially added and/or in-direct stimulation,due to the substantial pozzolanic ac-tivity of the silica fume in the early ages.)

When gypsum was added to the mix,the total heat after48h declined in all cases(calorimetric curves in Figs3and4).Nonetheless,more heat per gram of Port-land cement was released by the samples with gypsum.Conclusions

The conclusions that may be drawn from the experi-ments conducted with two types of Portland cement with very different mineralogical compositions,mixed with silica fume and gypsum,are as follows:?Silica fume,which exhibited pozzolanic activity at48h,stimulated the hydration reactions in the PC fractions with which it was mixed,both:

–directly:because of its size and shape(very small spheres,high specific surface),it demands greater amounts of mixing water,which would ultimately be the actual cause of this direct stimulation,and -indirectly:its chemical properties favour very sig-nificant pozzolanic activity at early stages.

This effect was so intense that in some cases it could be compared to a synergistic calorific effect.For this reason,when SF is added to cement to be used to make high performance bulk concrete,account must be taken of its direct and indirect effect on the generation of heat of hydration to minimize undesirable conse-quences,the risk of cracking,among others.?Whilst the addition of gypsum retarded and attenu-ated the hydration reactions in all cases(with a smaller amount of total heat after48h),it also gen-erated greater heat of hydration per gram of Port-land cement than when no gypsum was added.?The differences in the amount of heat produced per gram of Portland cement were more significant in mixes with Portland cement with a high C3A and low C3S content than in Portland cement with a low C3A and high C3S content.

Acknowledgements

We would like to thank the Fundación Rotaria and the Universidad Nacional de la Provincia de Buenos Aires,for finan-cial support,and the Instituto de C.C.‘Eduardo Torroja’-CSIC from Spain,as well,for providing the authors with necessary ce-menting materials and analytical and experimental techniques.

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Received:September19,2005

Accepted:March2,2006

OnlineFirst:June27,2006

DOI:10.1007/s10973-005-7324-1

RAHHAL et al.

外文翻译

Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the

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E---MARKETING (From:E--Marketing by Judy Strauss,Adel El--Ansary,Raymond Frost---3rd ed.1999 by Pearson Education pp .G4-G25.) As the growth of https://www.wendangku.net/doc/8013148809.html, shows, some marketing principles never change.Markets always welcome an innovative new product, even in a crowded field of competitors ,as long as it provides customer value.Also,Google`s success shows that customers trust good brands and that well-crafted marketing mix strategies can be effective in helping newcomers enter crowded markets. Nevertheless, organizations are scrambling to determine how they can use information technology profitably and to understand what technology means for their business strategies. Marketers want to know which of their time-ested concepts will be enhanced by the Internet, databases,wireless mobile devices, and other technologies. The rapid growth of the Internet and subsequent bursting of the dot-com bubble has marketers wondering,"What next?" This article attempts to answer these questions through careful and systematic examination of successful e-mar-keting strategies in light of proven traditional marketing practices. （Sales Promotion;E--Marketing；Internet；Strategic Planning ） 1.What is E--Marketing E--Marketing is the application of a broad range of information technologies for: Transforming marketing strategies to create more customer value through more effective segmentation ,and positioning strategies；More efficiently planning and executing the conception, distribution promotion,and pricing of goods,services,and ideas;andCreating exchanges that satisfy individual consumer and organizational customers` objectives. This definition sounds a lot like the definition of traditional marketing. Another way to view it is that e-marketing is the result of information technology applied to traditional marketing. E-marketing affects traditional marketing in two ways. First,it increases efficiency in traditional marketing strategies.The transformation results in new business models that add customer value and/or increase company profitability.

交通灯外文翻译 2

当今时代是一个自动化时代，交通灯控制等很多行业的设备都与计算机密切相关。因此，一个好的交通灯控制系统，将给道路拥挤，违章控制等方面给予技术革新。随着大规模集成电路及计算机技术的迅速发展，以及人工智能在控制技术方面的广泛运用，智能设备有了很大的发展，是现代科技发展的主流方向。本文介绍了一个智能交通的系统的设计。该智能交通灯控制系统可以实现的功能有：对某市区的四个主要交通路口进行控制：个路口有固定的工作周期，并且在道路拥挤时中控制中心能改变其周期：对路口违章的机动车能够即时拍照，并提取车牌号。在世界范围内，一个以微电子技术，计算机和通信技术为先导的，一信息技术和信息产业为中心的信息革命方兴未艾。而计算机技术怎样与实际应用更有效的结合并有效的发挥其作用是科学界最热门的话题，也是当今计算机应用中空前活跃的领域。本文主要从单片机的应用上来实现十字路口交通灯智能化的管理，用以控制过往车辆的正常运作。 研究交通的目的是为了优化运输，人流以及货流。由于道路使用者的不断增加，现有资源和基础设施有限，智能交通控制将成为一个非常重要的课题。但是，智能交通控制的应用还存在局限性。例如避免交通拥堵被认为是对环境和经济都有利的，但改善交通流也可能导致需求增加。交通仿真有几个不同的模型。在研究中，我们着重于微观模型，该模型能模仿单独车辆的行为，从而模仿动态的车辆组。 由于低效率的交通控制，汽车在城市交通中都经历过长时间的行进。采用先进的传感器和智能优化算法来优化交通灯控制系统，将会是非常有益的。优化交通灯开关，增加道路容量和流量，可以防止交通堵塞，交通信号灯控制是一个复杂的优化问题和几种智能算法的融合，如模糊逻辑，进化算法，和聚类算法已经在使用，试图解决这一问题，本文提出一种基于多代理聚类算法控制交通信号灯。 在我们的方法中，聚类算法与道路使用者的价值函数是用来确定每个交通灯的最优决策的，这项决定是基于所有道路使用者站在交通路口累积投票，通过估计每辆车的好处(或收益)来确定绿灯时间增益值与总时间是有差异的，它希望在它往返的时候等待，如果灯是红色，或者灯是绿色。等待，直到车辆到达目的地，通过有聚类算法的基础设施，最后经过监测车的监测。 我们对自己的聚类算法模型和其它使用绿灯模拟器的系统做了比较。绿灯模拟器是一个交通模拟器，监控交通流量统计，如平均等待时间，并测试不同的交通灯控制器。结果表明，在拥挤的交通条件下，聚类控制器性能优于其它所有测试的非自适应控制器，我们也测试理论上的平均等待时间，用以选择车辆通过市区的道路，并表明，道路使用者采用合作学习的方法可避免交通瓶颈。 本文安排如下：第2部分叙述如何建立交通模型，预测交通情况和控制交通。第3部分是就相关问题得出结论。第4部分说明了现在正在进一步研究的事实，并介绍了我们的新思想。

外文翻译

Journal of Industrial Textiles https://www.wendangku.net/doc/8013148809.html,/ Optimization of Parameters for the Production of Needlepunched Nonwoven Geotextiles Amit Rawal, Subhash Anand and Tahir Shah 2008 37: 341Journal of Industrial Textiles DOI: 10.1177/1528083707081594 The online version of this article can be found at: https://www.wendangku.net/doc/8013148809.html,/content/37/4/341 Published by: https://www.wendangku.net/doc/8013148809.html, can be found at:Journal of Industrial TextilesAdditional services and information for https://www.wendangku.net/doc/8013148809.html,/cgi/alertsEmail Alerts: https://www.wendangku.net/doc/8013148809.html,/subscriptionsSubscriptions: https://www.wendangku.net/doc/8013148809.html,/journalsReprints.navReprints: https://www.wendangku.net/doc/8013148809.html,/journalsPermissions.navPermissions: https://www.wendangku.net/doc/8013148809.html,/content/37/4/341.refs.htmlCitations: - Mar 28, 2008Version of Record >>

国际贸易英文文献

Strategic transformations in Danish and Swedish big business in an era of globalisation, 1973-2008 The Danish and Swedish context In the difficult inter-war period, a state-supported, protected home market orientation had helped stabilise both Denmark’s and Sweden’s economies, but after WorldWar II priorities changed. Gradually and in accordance with the international economic development, restrictions on foreign trade were removed, and Danish and Swedish industry was exposed to international competition. As a consequence, several home market oriented industries –such as the textile and the shoe industry –were more or less outperformed, while in Sweden the engineering industry soon became the dominant leader of Swedish industry, with companies such as V olvo, Ericsson, Electrolux, ASEA and SKF. In the Danish case, the SMEs continued to be dominant but in combination with expanding export oriented industrial manufacturers such as Lego, Danfoss, Carlsberg and the shipping conglomerates ok and A.P. moller-Marsk. In Sweden and Denmark stable economic growth continued into the 1970s, but due to the problems during the oil crises, the economies came into fundamental structural troubles for the first time since World War II. In the beginning this was counteracted by traditional Keynesian policy measures. However, because of large budget deficits, inflation and increasing wages, both the Danish economy from 1974 and the Swedish economy from 1976 encountered severe problems. Towards the late 1970s Denmark’s and Sweden’s economic policies were thus increasingly questioned. It was clear that Keynesian policy could not solve all economic problems. Expansive fiscal policies in terms of continued deficits on the state budget could not compensate for the loss of both national and international markets and step by step the Keynesian economic policy was abandoned. The increased budget deficit also made it difficult for the state to support employment and regional development. These kinds of heavy governmental activities were also hardly acceptable under the more market oriented policy that developed first in Great Britain and the USA, but in the 1980s also in Denmark and Sweden (Iversen & Andersen, 2008, pp. 313–315; Sjo¨ gren, 2008, pp. 46–54). These changes in political priorities were especially noticeable in the financial market. After being the most state regulated and coordinated sector of the economy since the 1950s, then between 1980 and 1985 the Danish and Swedish financial markets underwent an extensive deregulation resulting in increased competition. Lending from banks and other credit institutes was no longer regulated, and neither were interest rates. The bond market was also opened as the issuance of new bond loans was deregulated in Sweden in 1983. When the control of foreign capital flows was liberalised in the late 1980s the last extraordinary restriction was now gone. Together with the establishment of the new money market with options and derivates, this opened up to a much larger credit market and the possibility for companies to finance investments and increase business domestically as well as abroad (Larsson, 1998, pp. 205–207). Another important part of the regulatory changes in the early 1980s were new rules for the Copenhagen and Stockholm stock exchanges. Introduction on the stock exchange was made much

外文翻译中文版(完整版)

毕业论文外文文献翻译 毕业设计（论文）题目关于企业内部环境绩效审计的研究翻译题目最高审计机关的环境审计活动 学院会计学院 专业会计学 姓名张军芳 班级09020615 学号09027927 指导教师何瑞雄

最高审计机关的环境审计活动 1最高审计机关越来越多的活跃在环境审计领域。特别是1993-1996年期间，工作组已检测到环境审计活动坚定的数量增长。首先，越来越多的最高审计机关已经活跃在这个领域。其次是积极的最高审计机关，甚至变得更加活跃：他们分配较大部分的审计资源给这类工作，同时出版更多环保审计报告。表1显示了平均数字。然而，这里是机构间差异较大。例如，环境报告的数量变化，每个审计机关从1到36份报告不等。 1996-1999年期间，结果是不那么容易诠释。第一，活跃在环境审计领域的最高审计机关数量并没有太大变化。“活性基团”的组成没有保持相同的：一些最高审计机关进入，而其他最高审计机关离开了团队。环境审计花费的时间量略有增加。二，但是，审计报告数量略有下降，1996年和1999年之间。这些数字可能反映了从量到质的转变。这个信号解释了在过去三年从规律性审计到绩效审计的转变（1994-1996年，20％的规律性审计和44％绩效审计;1997-1999：16％规律性审计和绩效审计54％）。在一般情况下，绩效审计需要更多的资源。我们必须认识到审计的范围可能急剧变化。在将来，再将来开发一些其他方式去测算人们工作量而不是计算通过花费的时间和发表的报告会是很有趣的。 在2000年，有62个响应了最高审计机关并向工作组提供了更详细的关于他们自1997年以来公布的工作信息。在1997-1999年，这62个最高审计机关公布的560个环境审计报告。当然，这些报告反映了一个庞大的身躯，可用于其他机构的经验。环境审计报告的参考书目可在网站上的最高审计机关国际组织的工作组看到。这里这个信息是用来给最高审计机关的审计工作的内容更多一些洞察。 自1997年以来，少数环境审计是规律性审计（560篇报告中有87篇，占16％）。大多数审计绩效审计（560篇报告中有304篇，占54％），或组合的规律性和绩效审计（560篇报告中有169篇，占30％）。如前文所述，绩效审计是一个广泛的概念。在实践中，绩效审计往往集中于环保计划的实施（560篇报告中有264篇，占47％），符合国家环保法律，法规的，由政府部门，部委和/或其他机构的任务给访问（560篇报告中有212篇，占38％）。此外，审计经常被列入政府的环境管理系统（560篇报告中有156篇，占28％）。下面的元素得到了关注审计报告：影响或影响现有的国家环境计划非环保项目对环境的影响;环境政策;由政府遵守国际义务和承诺的10％至20％。许多绩效审计包括以上提到的要素之一。 1本文译自：S. Van Leeuwen.(2004).’’Developments in Environmental Auditing by Supreme Audit Institutions’’ Environmental Management Vol. 33, No. 2, pp. 163–1721

中国的对外贸易外文翻译及原文

外文翻译 原文 Foreign T rade o f China Material Source:W anfang Database Author:Hitomi Iizaka 1.Introduction On December11,2001,China officially joined the World T rade Organization(WTO)and be c a me its143rd member.China’s presence in the worl d economy will continue to grow and deepen.The foreign trade sector plays an important andmultifaceted role in China’s economic development.At the same time, China’s expanded role in the world economy is beneficial t o all its trading partners. Regions that trade with China benefit from cheaper and mor e varieties of imported consumer goods,raw materials and intermediate products.China is also a large and growing export market.While the entry of any major trading nation in the global trading system can create a process of adjustment,the o u t c o me is fundamentally a win-win situation.In this p aper we would like t o provide a survey of the various institutions,laws and characteristics of China’s trade.Among some of the findings, we can highlight thefollowing: ?In2001,total trade to gross domestic pr oduct(GDP)ratio in China is44% ?In2001,47%of Chinese trade is processed trade1 ?In2001,51%of Chinese trade is conduct ed by foreign firms in China2 ?In2001,36%of Chinese exports originate from Gu an gdon g province ?In2001,39%of China’s exports go through Hong Kong to be re-exported elsewhere 2.Evolution of China’s Trade Regime Equally remarkable are the changes in the commodity composition of China’s exports and imports.Table2a shows China’s annu al export volumes of primary goods and manufactured goods over time.In1980,primary goods accounted for 50.3%of China’s exports and manufactured goods accounted for49.7%.Although the share of primary good declines slightly during the first half of1980’s,it remains at50.6%in1985.Since then,exports of manufactured goods have grown at a much

营销-外文翻译

外文翻译 原文 Marketing Material Source：Marketing Management Author：Philip Kotler Marketing Channels To reach a target market, the marketer uses three kinds of marketing channels. Communication channels deliver messages to and receive messages from target buyers. They include newspapers, magazines, radio, television, mail, telephone, billboards, posters, fliers, CDs, audiotapes, and the Internet. Beyond these, communications are conveyed by facial expressions and clothing, the look of retail stores, and many other media. Marketers are increasingly adding dialogue channels (e-mail and toll-free numbers) to counterbalance the more normal monologue channels (such as ads). The marketer uses distribution channels to display or deliver the physical product or service to the buyer or user. There are physical distribution channels and service distribution channels, which include warehouses, transportation vehicles, and various trade channels such as distributors, wholesalers, and retailers. The marketer also uses selling channels to effect transactions with potential buyers. Selling channels include not only the distributors and retailers but also the banks and insurance companies that facilitate transactions. Marketers clearly face a design problem in choosing the best mix of communication, distribution, and selling channels for their offerings. Supply Chain Whereas marketing channels connect the marketer to the target buyers, the supply chain describes a longer channel stretching from raw materials to components to final products that are carried to final buyers. For example, the supply chain for women’s purses starts with hides, tanning operations, cutting operations, manufacturing, and the marketing channels that bring products to customers. This supply chain represents a value delivery system. Each company captures only a certain percentage of the total value generated by the supply chain. When a company acquires competitors or moves upstream or downstream, its aim is

智能交通灯控制系统_英文翻译

英文 Because of the rapid development of our economy resulting in the car number of large and medium-sized cities surged and the urban traffic, is facing serious test, leading to the traffic problem increasingly serious, its basically are behaved as follows: traffic accident frequency, to the human life safety enormous threat, Traffic congestion, resulting in serious travel time increases, energy consumption increase; Air pollution and noise pollution degree of deepening, etc. Daily traffic jams become people commonplace and had to endure. In this context, in combination with the actual situation of urban road traffic, develop truly suitable for our own characteristics of intelligent signal control system has become the main task. Preface In practical application at home and abroad, according to the actual traffic signal control application inspection, planar independent intersection signal control basic using set cycle, much time set cycle, half induction, whole sensor etc in several ways. The former two control mode is completely based on planar intersection always traffic flow data of statistical investigation, due to traffic flow the existence of variable sex and randomicity, the two methods have traffic efficiency is low, the scheme, the defects of aging and half inductive and all the inductive the two methods are in the former two ways based on increased vehicle detector and according to the information provided to adjust cycle is long and green letter of vehicle, it than random arrived adaptability bigger, can make vehicles in the parking cord before as few parking, achieve traffic flowing effect In modern industrial production,current,voltage,temperature, pressure, and flow rate, velocity, and switch quantity are common mainly controlled parameter. For example: in metallurgical industry, chemical production, power engineering, the papermaking industry, machinery and food processing and so on many domains, people need to transport the orderly control. By single chip microcomputer to control of traffic, not only has the convenient control, configuration simple and flexible wait for an advantage, but also can greatly improve the technical index by control quantity, thus greatly improve product quality and quantity. Therefore, the monolithic integrated circuit to the traffic light control problem is an industrial production we often encounter problems. In the course of industrial production, there are many industries have lots of traffic equipment, in the current system, most of the traffic control signal is accomplished by relays, but relays response time is long, sensitivity low, long-term after use, fault opportunity increases greatly, and adopts single-chip microcomputer control, the accuracy of far greater than relays, short response time, software reliability, not because working time reduced its performance sake, compared with, this solution has the high feasibility. About AT89C51 (1)function characteristics description: AT89C51 is a low power consumption, high performance CMOS8 bit micro-controller, has the 8K in system programmable Flash memory. Use high-density Atmel company the beltpassword nonvolatile storage technology and manufacturing, and industrial 80S51 product instructions and pin fully compatible. Chip Flash allow program memory in system programmable, also suitable for conventional programmer. In a single chip, have dexterous 8 bits CPU and in system programmable Flash, make AT89C51 for many embedded control application system provides the high flexible, super efficient solution. AT89C51 has the following standard function: 8k bytes Flash, 256 bytes RAM, 32-bit I/O mouth line, the watchdog timer, two data pointer, three 16 timer/counter, a 6 vector level 2 interrupt structure, full-duplex serial port, piece inside crystals timely clock circuit. In addition, AT89C51 can drop to 0Hz static logic operation, support two software can choose power saving mode. Idle mode, the CPU to stop working, allowing the RAM, timer/counter, serial ports, interruption continue to work. Power lost protection mode, RAM content being saved, has been frozen, microcontroller all work stop, until the next interruption or hardware reset so far. As shown in