毕业论文英文翻译
毕业论文(设计)外文文献翻译及原文
金融体制、融资约束与投资——来自OECD的实证分析R．SemenovDepartment of Economics，University of Nijmegen，Nijmegen（荷兰内梅亨大学，经济学院）这篇论文考查了OECD的11个国家中现金流量对企业投资的影响.我们发现不同国家之间投资对企业内部可获取资金的敏感性具有显著差异,并且银企之间具有明显的紧密关系的国家的敏感性比银企之间具有公平关系的国家的低.同时，我们发现融资约束与整体金融发展指标不存在关系.我们的结论与资本市场信息和激励问题对企业投资具有重要作用这种观点一致，并且紧密的银企关系会减少这些问题从而增加企业获取外部融资的渠道。
一、引言各个国家的企业在显著不同的金融体制下运行。
金融发展水平的差别(例如，相对GDP的信用额度和相对GDP的相应股票市场的资本化程度），在所有者和管理者关系、企业和债权人的模式中，企业控制的市场活动水平可以很好地被记录.在完美资本市场,对于具有正的净现值投资机会的企业将一直获得资金。
然而，经济理论表明市场摩擦，诸如信息不对称和激励问题会使获得外部资本更加昂贵，并且具有盈利投资机会的企业不一定能够获取所需资本.这表明融资要素，例如内部产生资金数量、新债务和权益的可得性，共同决定了企业的投资决策.现今已经有大量考查外部资金可得性对投资决策的影响的实证资料（可参考，例如Fazzari（1998）、 Hoshi(1991)、 Chapman（1996）、Samuel(1998））.大多数研究结果表明金融变量例如现金流量有助于解释企业的投资水平。
这项研究结果解释表明企业投资受限于外部资金的可得性。
很多模型强调运行正常的金融中介和金融市场有助于改善信息不对称和交易成本，减缓不对称问题,从而促使储蓄资金投着长期和高回报的项目,并且提高资源的有效配置（参看Levine（1997)的评论文章）。
因而我们预期用于更加发达的金融体制的国家的企业将更容易获得外部融资.几位学者已经指出建立企业和金融中介机构可进一步缓解金融市场摩擦。
自动化专业毕业论文外文文献翻译
目录Part 1 PID type fuzzy controller and parameters adaptive method (1)Part 2 Application of self adaptation fuzzy-PID control for main steam temperature control system in power station (7)Part 3 Neuro-fuzzy generalized predictive control of boiler steam temperature ..................................................................... (13)Part 4 为Part3译文：锅炉蒸汽温度模糊神经网络的广义预测控制21Part 1 PID type fuzzy controller and Parametersadaptive methodWu zhi QIAO, Masaharu MizumotoAbstract: The authors of this paper try to analyze the dynamic behavior of the product-sum crisp type fuzzy controller, revealing that this type of fuzzy controller behaves approximately like a PD controller that may yield steady-state error for the control system. By relating to the conventional PID control theory, we propose a new fuzzy controller structure, namely PID type fuzzy controller which retains the characteristics similar to the conventional PID controller. In order to improve further the performance of the fuzzy controller, we work out a method to tune the parameters of the PID type fuzzy controller on line, producing a parameter adaptive fuzzy controller. Simulation experiments are made to demonstrate the fine performance of these novel fuzzy controller structures.Keywords: Fuzzy controller; PID control; Adaptive control1. IntroductionAmong various inference methods used in the fuzzy controller found in literatures , the most widely used ones in practice are the Mamdani method proposed by Mamdani and his associates who adopted the Min-max compositional rule of inference based on an interpretation of a control rule as a conjunction of the antecedent and consequent, and the product-sum method proposed by Mizumoto who suggested to introduce the product and arithmetic mean aggregation operators to replace the logical AND (minimum) and OR (maximum) calculations in the Min-max compositional rule of inference.In the algorithm of a fuzzy controller, the fuzzy function calculation is also a complicated and time consuming task. Tagagi and Sugeno proposed a crisp type model in which the consequent parts of the fuzzy control rules are crisp functional representation or crisp real numbers in the simplified case instead of fuzzy sets . With this model of crisp real number output, the fuzzy set of the inference consequence willbe a discrete fuzzy set with a finite number of points, this can greatly simplify the fuzzy function algorithm.Both the Min-max method and the product-sum method are often applied with the crisp output model in a mixed manner. Especially the mixed product-sum crisp model has a fine performance and the simplest algorithm that is very easy to be implemented in hardware system and converted into a fuzzy neural network model. In this paper, we will take account of the product-sum crisp type fuzzy controller.2. PID type fuzzy controller structureAs illustrated in previous sections, the PD function approximately behaves like a parameter time-varying PD controller. Since the mathematical models of most industrial process systems are of type, obviously there would exist an steady-state error if they are controlled by this kind of fuzzy controller. This characteristic has been stated in the brief review of the PID controller in the previous section.If we want to eliminate the steady-state error of the control system, we can imagine to substitute the input (the change rate of error or the derivative of error) of the fuzzy controller with the integration of error. This will result the fuzzy controller behaving like a parameter time-varying PI controller, thus the steady-state error is expelled by the integration action. However, a PI type fuzzy controller will have a slow rise time if the P parameters are chosen small, and have a large overshoot if the P or I parameters are chosen large. So there may be the time when one wants to introduce not only the integration control but the derivative control to the fuzzy control system, because the derivative control can reduce the overshoot of the system's response so as to improve the control performance. Of course this can be realized by designing a fuzzy controller with three inputs, error, the change rate of error and the integration of error. However, these methods will be hard to implement in practice because of the difficulty in constructing fuzzy control rules. Usually fuzzy control rules are constructed by summarizing the manual control experience of an operator who has been controlling the industrial process skillfully and successfully. The operator intuitively regulates the executor to control the process by watching theerror and the change rate of the error between the system's output and the set-point value. It is not the practice for the operator to observe the integration of error. Moreover, adding one input variable will greatly increase the number of control rules, the constructing of fuzzy control rules are even more difficult task and it needs more computation efforts. Hence we may want to design a fuzzy controller that possesses the fine characteristics of the PID controller by using only the error and the change rate of error as its inputs.One way is to have an integrator serially connected to the output of the fuzzy controller as shown in Fig. 1. In Fig. 1,1K and 2K are scaling factors for e and ~ respectively, and fl is the integral constant. In the proceeding text, for convenience, we did not consider the scaling factors. Here in Fig. 2, when we look at the neighborhood of NODE point in the e - ~ plane, it follows from (1) that the control input to the plant can be approximated by(1)Hence the fuzzy controller becomes a parameter time-varying PI controller, itsequivalent proportional control and integral control components are BK2D and ilK1 P respectively. We call this fuzzy controller as the PI type fuzzy controller (PI fc). We can hope that in a PI type fuzzy control system, the steady-state error becomes zero.To verify the property of the PI type fuzzy controller, we carry out some simulation experiments. Before presenting the simulation, we give a description of the simulation model. In the fuzzy control system shown in Fig. 3, the plant model is a second-order and type system with the following transfer function:)1)(1()(21++=s T s T K s G (2) Where K = 16, 1T = 1, and 2T = 0.5. In our simulation experiments, we use thediscrete simulation method, the results would be slightly different from that of a continuous system, the sampling time of the system is set to be 0.1 s. For the fuzzy controller, the fuzzy subsets of e and d are defined as shown in Fig. 4. Their coresThe fuzzy control rules are represented as Table 1. Fig. 5 demonstrates the simulation result of step response of the fuzzy control system with a Pl fc. We can see that the steady-state error of the control system becomes zero, but when the integration factor fl is small, the system's response is slow, and when it is too large, there is a high overshoot and serious oscillation. Therefore, we may want to introduce the derivative control law into the fuzzy controller to overcome the overshoot and instability. We propose a controller structure that simply connects the PD type and the PI type fuzzy controller together in parallel. We have the equivalent structure of that by connecting a PI device with the basic fuzzy controller serially as shown in Fig.6. Where ~ is the weight on PD type fuzzy controller and fi is that on PI type fuzzy controller, the larger a/fi means more emphasis on the derivative control and less emphasis on the integration control, and vice versa. It follows from (7) that the output of the fuzzy controller is(3)3. The parameter adaptive methodThus the fuzzy controller behaves like a time-varying PID controller, its equivalent proportional control, integral control and derivative control components are respectively. We call this new controller structure a PID type fuzzy controller (PID fc). Figs. 7 and 8 are the simulation results of the system's step response of such control system. The influence of ~ and fl to the system performance is illustrated. When ~ > 0 and/3 = 0, meaning that the fuzzy controller behaves like PD fc, there exist a steady-state error. When ~ = 0 and fl > 0, meaning that the fuzzy controller behaves like a PI fc, the steady-state error of the system is eliminated but there is a large overshoot and serious oscillation.When ~ > 0 and 13 > 0 the fuzzy controller becomes a PID fc, the overshoot is substantially reduced. It is possible to get a comparatively good performance by carefully choosing the value of αandβ.4. ConclusionsWe have studied the input-output behavior of the product-sum crisp type fuzzy controller, revealing that this type of fuzzy controller behaves approximately like a parameter time-varying PD controller. Therefore, the analysis and designing of a fuzzy control system can take advantage of the conventional PID control theory. According to the coventional PID control theory, we have been able to propose some improvement methods for the crisp type fuzzy controller.It has been illustrated that the PD type fuzzy controller yields a steady-state error for the type system, the PI type fuzzy controller can eliminate the steady-state error. We proposed a controller structure, that combines the features of both PD type and PI type fuzzy controller, obtaining a PID type fuzzy controller which allows the control system to have a fast rise and a small overshoot as well as a short settling time.To improve further the performance of the proposed PID type fuzzy controller, the authors designed a parameter adaptive fuzzy controller. The PID type fuzzy controller can be decomposed into the equivalent proportional control, integral control and the derivative control components. The proposed parameter adaptive fuzzy controller decreases the equivalent integral control component of the fuzzy controller gradually with the system response process time, so as to increase the damping of the system when the system is about to settle down, meanwhile keeps the proportional control component unchanged so as to guarantee quick reaction against the system's error. With the parameter adaptive fuzzy controller, the oscillation of the system is strongly restrained and the settling time is shortened considerably.We have presented the simulation results to demonstrate the fine performance of the proposed PID type fuzzy controller and the parameter adaptive fuzzy controller structure.Part 2 Application of self adaptation fuzzy-PID control for main steam temperature control system inpower stationZHI-BIN LIAbstract: In light of the large delay, strong inertia, and uncertainty characteristics of main steam temperature process, a self adaptation fuzzy-PID serial control system is presented, which not only contains the anti-disturbance performance of serial control, but also combines the good dynamic performance of fuzzy control. The simulation results show that this control system has more quickly response, better precision and stronger anti-disturbance ability．Keywords：Main steam temperature；Self adaptation；Fuzzy control；Serial control1. IntroductionThe boiler superheaters of modem thermal power station run under the condition of high temperature and high pressure, and the superheater’s temperature is highest in the steam channels．so it has important effect to the running of the whole thermal power station．If the temperature is too high, it will be probably burnt out. If the temperature is too low ,the efficiency will be reduced So the main steam temperature mast be strictly controlled near the given value．Fig l shows the boiler main steam temperature system structure.Fig.1 boiler main steam temperature systemIt can be concluded from Fig l that a good main steam temperature controlsystem not only has adequately quickly response to flue disturbance and load fluctuation, but also has strong control ability to desuperheating water disturbance. The general control scheme is serial PID control or double loop control system with derivative. But when the work condition and external disturbance change large, the performance will become instable. This paper presents a self adaptation fuzzy-PID serial control system. which not only contains the anti-disturbance performance of serial control, but also combines the good dynamic character and quickly response of fuzzy control ．1. Design of Control SystemThe general regulation adopts serial PID control system with load feed forward ．which assures that the main steam temperature is near the given value 540℃in most condition ．If parameter of PID control changeless and the work condition and external disturbance change large, the performance will become in stable ．The fuzzy control is fit for controlling non-linear and uncertain process. The general fuzzy controller takes error E and error change ratio EC as input variables ．actually it is a non-linear PD controller, so it has the good dynamic performance ．But the steady error is still in existence. In linear system theory, integral can eliminate the steady error. So if fuzzy control is combined with PI control, not only contains the anti-disturbance performance of serial control, but also has the good dynamic performance and quickly response.In order to improve fuzzy control self adaptation ability, Prof ．Long Sheng-Zhao and Wang Pei-zhuang take the located in bringing forward a new idea which can modify the control regulation online ．This regulation is:]1,0[,)1(∈-+=αααEC E UThis control regulation depends on only one parameter α.Once αis fixed ．the weight of E and EC will be fixed and the self adaptation ability will be very small ．It was improved by Prof. Li Dong-hui and the new regulation is as follow;]1,0[,,,3,)1(2,)1(1,)1(0,)1({321033221100∈±=-+±=-+±=-+=-+=ααααααααααααE EC E E EC E E EC E E EC E UBecause it is very difficult to find a self of optimum parameter, a new method is presented by Prof ．Zhou Xian-Lan, the regulation is as follow:)0(),ex p(12>--=k ke αBut this algorithm still can not eliminate the steady error ．This paper combines this algorithm with PI control ，the performance is improved ．2. Simulation of Control System3.1 Dynamic character of controlled objectPapers should be limited to 6 pages Papers longer than 6 pages will be subject to extra fees based on their length ．Fig .2 main steam temperature control system structureFig 2 shows the main steam temperature control system structure ，)(),(21s W s W δδare main controller and auxiliary controller,)(),(21s W s W o o are characters of the leading and inertia sections,)(),(21s W s W H H are measure unit.3.2 Simulation of the general serial PID control systemThe simulation of the general serial PID control system is operated by MATLAB, the simulation modal is as Fig.3.Setp1 and Setp2 are the given value disturbance and superheating water disturb & rice .PID Controller1 and PID Controller2 are main controller and auxiliary controller ．The parameter value which comes from references is as follow ：667.37,074.0,33.31)(25)(111111122===++===D I p D I p p k k k s k sk k s W k s W δδFig.3. the general PID control system simulation modal3.3 Simulation of self adaptation fuzzy-PID control system SpacingThe simulation modal is as Fig 4.Auxiliary controller is:25)(22==p k s W δ.Main controller is Fuzzy-PI structure, and the PI controller is:074.0,33.31)(11111==+=I p I p k k s k k s W δFuzzy controller is realized by S-function, and the code is as fig.5.Fig.4. the fuzzy PID control system simulation modalFig 5 the S-function code of fuzzy control3.4 Comparison of the simulationGiven the same given value disturbance and the superheating water disturbance，we compare the response of fuzzy-PID control system with PID serial control system. The simulation results are as fig.6-7.From Fig6-7,we can conclude that the self adaptation fuzzy-PID control system has the more quickly response, smaller excess and stronger anti-disturbance．4. Conclusion(1)Because it combines the advantage of PID controller and fuzzy controller, theself adaptation fuzzy-PID control system has better performance than the general PID serial control system.(2)The parameter can self adjust according to the error E value. so this kind of controller can harmonize quickly response with system stability．Part 3 Neuro-fuzzy generalized predictive controlof boiler steam temperatureXiangjie LIU, Jizhen LIU, Ping GUANAbstract: Power plants are nonlinear and uncertain complex systems. Reliable control of superheated steam temperature is necessary to ensure high efficiency and high load-following capability in the operation of modern power plant. A nonlinear generalized predictive controller based on neuro-fuzzy network (NFGPC) is proposed in this paper. The proposed nonlinear controller is applied to control the superheated steam temperature of a 200MW power plant. From the experiments on the plant and the simulation of the plant, much better performance than the traditional controller is obtained.Keywords: Neuro-fuzzy networks; Generalized predictive control; Superheated steam temperature1. IntroductionContinuous process in power plant and power station are complex systems characterized by nonlinearity, uncertainty and load disturbance. The superheater is an important part of the steam generation process in the boiler-turbine system, where steam is superheated before entering the turbine that drives the generator. Controlling superheated steam temperature is not only technically challenging, but also economically important.From Fig.1,the steam generated from the boiler drum passes through the low-temperature superheater before it enters the radiant-type platen superheater. Water is sprayed onto the steam to control the superheated steam temperature in both the low and high temperature superheaters. Proper control of the superheated steam temperature is extremely important to ensure the overall efficiency and safety of the power plant. It is undesirable that the steam temperature is too high, as it can damage the superheater and the high pressure turbine, or too low, as it will lower the efficiency of the power plant. It is also important to reduce the temperaturefluctuations inside the superheater, as it helps to minimize mechanical stress that causes micro-cracks in the unit, in order to prolong the life of the unit and to reduce maintenance costs. As the GPC is derived by minimizing these fluctuations, it is amongst the controllers that are most suitable for achieving this goal.The multivariable multi-step adaptive regulator has been applied to control the superheated steam temperature in a 150 t/h boiler, and generalized predictive control was proposed to control the steam temperature. A nonlinear long-range predictive controller based on neural networks is developed into control the main steam temperature and pressure, and the reheated steam temperature at several operating levels. The control of the main steam pressure and temperature based on a nonlinear model that consists of nonlinear static constants and linear dynamics is presented in that.Fig.1 The boiler and superheater steam generation process Fuzzy logic is capable of incorporating human experiences via the fuzzy rules. Nevertheless, the design of fuzzy logic controllers is somehow time consuming, as the fuzzy rules are often obtained by trials and errors. In contrast, neural networks not only have the ability to approximate non-linear functions with arbitrary accuracy, they can also be trained from experimental data. The neuro-fuzzy networks developed recently have the advantages of model transparency of fuzzy logic and learning capability of neural networks. The NFN is have been used to develop self-tuning control, and is therefore a useful tool for developing nonlinear predictive control. Since NFN is can be considered as a network that consists of several local re-gions, each of which contains a local linear model, nonlinear predictive control based onNFN can be devised with the network incorporating all the local generalized predictive controllers (GPC) designed using the respective local linear models. Following this approach, the nonlinear generalized predictive controllers based on the NFN, or simply, the neuro-fuzzy generalized predictive controllers (NFG-PCs)are derived here. The proposed controller is then applied to control the superheated steam temperature of the 200MW power unit. Experimental data obtained from the plant are used to train the NFN model, and from which local GPC that form part of the NFGPC is then designed. The proposed controller is tested first on the simulation of the process, before applying it to control the power plant.2. Neuro-fuzzy network modellingConsider the following general single-input single-output nonlinear dynamic system:),1(),...,(),(),...,1([)(''+-----=uy n d t u d t u n t y t y f t y ∆+--/)()](),...,1('t e n t e t e e (1)where f[.]is a smooth nonlinear function such that a Taylor series expansion exists, e(t)is a zero mean white noise and Δis the differencing operator,''',,e u y n n n and d are respectively the known orders and time delay of the system. Let the local linear model of the nonlinear system (1) at the operating point )(t o be given by the following Controlled Auto-Regressive Integrated Moving Average (CARIMA) model:)()()()()()(111t e z C t u z B z t y z A d ----+∆= (2) Where )()(),()(1111----∆=z andC z B z A z A are polynomials in 1-z , the backward shift operator. Note that the coefficients of these polynomials are a function of the operating point )(t o .The nonlinear system (1) is partitioned into several operating regions, such that each region can be approximated by a local linear model. Since NFN is a class of associative memory networks with knowledge stored locally, they can be applied to model this class of nonlinear systems. A schematic diagram of the NFN is shown in Fig.2.B-spline functions are used as the membership functions in theNFN for the following reasons. First, B-spline functions can be readily specified by the order of the basis function and the number of inner knots. Second, they are defined on a bounded support, and the output of the basis function is always positive, i.e.,],[,0)(j k j j k x x λλμ-∉=and ],[,0)(j k j j k x x λλμ-∈>.Third, the basis functions form a partition of unity, i.e.,.][,1)(min,∑∈≡j mam j k x x x x μ(3)And fourth, the output of the basis functions can be obtained by a recurrence equation.Fig. 2 neuro-fuzzy network The membership functions of the fuzzy variables derived from the fuzzy rules can be obtained by the tensor product of the univariate basis functions. As an example, consider the NFN shown in Fig.2, which consists of the following fuzzy rules: IF operating condition i (1x is positive small, ... , and n x is negative large),THEN the output is given by the local CARIMA model i:...)()(ˆ...)1(ˆ)(ˆ01+-∆+-++-=d t u b n t y a t y a t yi i a i in i i i a )(...)()(c i in i b i in n t e c t e n d t u b c b -+++--∆+ (4)or )()()()()(ˆ)(111t e z C t u z B z t yz A i i i i d i i ----+∆= (5) Where )()(),(111---z andC z B z A i i i are polynomials in the backward shift operator 1-z , and d is the dead time of the plant,)(t u i is the control, and )(t e i is a zero mean independent random variable with a variance of 2δ. The multivariate basis function )(k i x a is obtained by the tensor products of the univariate basis functions,p i x A a nk k i k i ,...,2,1,)(1==∏=μ (6)where n is the dimension of the input vector x , and p , the total number of weights in the NFN, is given by,∏=+=nk i i k R p 1)( (7)Where i k and i R are the order of the basis function and the number of inner knots respectively. The properties of the univariate B-spline basis functions described previously also apply to the multivariate basis function, which is defined on the hyper-rectangles. The output of the NFN is,∑∑∑=====p i i i p i ip i i i a y aa yy 111ˆˆˆ (8) 3. Neuro-fuzzy modelling and predictive control of superheatedsteam temperatureLet θbe the superheated steam temperature, and θμ, the flow of spray water to the high temperature superheater. The response of θcan be approximated by a second order model:The linear models, however, only a local model for the selected operating point. Since load is the unique antecedent variable, it is used to select the division between the local regions in the NFN. Based on this approach, the load is divided into five regions as shown in Fig.3,using also the experience of the operators, who regard a load of 200MW as high,180MW as medium high,160MW as medium,140MW as medium low and 120MW as low. For a sampling interval of 30s , the estimated linear local models )(1-z A used in the NFN are shown in Table 1.Fig. 3 Membership function for local modelsTable 1 Local CARIMA models in neuro-fuzzy modelCascade control scheme is widely used to control the superheated steam temperature. Feed forward control, with the steam flow and the gas temperature as inputs, can be applied to provide a faster response to large variations in these two variables. In practice, the feed forward paths are activated only when there are significant changes in these variables. The control scheme also prevents the faster dynamics of the plant, i.e., the spray water valve and the water/steam mixing, from affecting the slower dynamics of the plant, i.e., the high temperature superheater. With the global nonlinear NFN model in Table 1, the proposed NFGPC scheme is shown in Fig.4.Fig. 4 NFGPC control of superheated steam temperature with feed-for-ward control.As a further illustration, the power plant is simulated using the NFN model given in Table 1,and is controlled respectively by the NFGPC, the conventional linear GPC controller, and the cascaded PI controller while the load changes from 160MW to 200MW.The conventional linear GPC controller is the local controller designed for the“medium”operating region. The results are shown in Fig.5,showing that, as expected, the best performance is obtained from the NFGPC as it is designed based on a more accurate process model. This is followed by the conventional linear GPC controller. The performance of the conventional cascade PI controller is the worst, indicating that it is unable to control satisfactory the superheated steam temperature under large load changes. This may be the reason for controlling the power plant manually when there are large load changes.Fig.5 comparison of the NFGPC, conventional linear GPC, and cascade PI controller.4. ConclusionsThe modeling and control of a 200 MW power plant using the neuro-fuzzy approach is presented in this paper. The NFN consists of five local CARIMA models.The out-put of the network is the interpolation of the local models using memberships given by the B-spline basis functions. The proposed NFGPC is similarly constructed, which is designed from the CARIMA models in the NFN. The NFGPC is most suitable for processes with smooth nonlinearity, such that its full operating range can be partitioned into several local linear operating regions. The proposed NFGPC therefore provides a useful alternative for controlling this class of nonlinear power plants, which are formerly difficult to be controlled using traditional methods.Part 4 为Part3译文：锅炉蒸汽温度模糊神经网络的广义预测控制Xiangjie LIU, Jizhen LIU, Ping GUAN摘要：发电厂是非线性和不确定性的复杂系统。
浙江大学本科毕业论文外文文献翻译
核准通过，归档资料。
未经允许，请勿外传!浙江大学本科毕业论文外文文献翻译The influence of political connections on the firm value of small and medium-sized enterprises in China政治关联在中国对中小型企业价值的影响1摘要中小型企业的价值受很多因素的影响,比如股东、现金流以及政治关联等.这篇文章调查的正是在中国政治关联对中小型企业价值的影响。
通过实验数据来分析政治关联对企业价值效益的影响.结果表明政府关联是关键的因素并且在中国对中小型企业的价值具有负面影响。
2重要内容翻译2。
1引言在商业界,有越来越多关于政治关联的影响的经济研究。
它们发现政治关联能够帮助企业确保有利的规章条件以及成功获得资源，比如能够最终提高企业价值或是提升绩效的银行贷款，这种政治关联的影响在不同的经济条件下呈现不同的效果。
在高腐败和法律制度薄弱的国家，政治关联对企业价值具有决定性因素1的作用.中国由高度集权的计划经济向市场经济转变，政府对市场具有较强的控制作用，而且有大量的上市企业具有政治关联。
中小型企业发展的很迅速，他们已经在全球经济环境中变得越来越重要。
从90年代起, 政治因素对中国的任何规模的企业来说都变得越来越重要,尤其是中小型企业的价值。
和其他的部门相比较，中小型企业只有较小的现金流，不稳定的现金流且高负债率.一方面，中小型企业改变更加灵活；另一方面,中小型企业在由于企业规模以及对银行来说没有可以抵押的资产，在筹资方面较为困难。
企业如何应对微观经济环境和政策去保证正常的企业活动，并且政治关联如何影响企业价值？这篇论文调查政治关联和企业价值之间的联系,并且试图去研究企业是否可以从政治关联中获利提升企业价值。
2.2定义这些中小型企业之所以叫中小型企业，是和管理规模有关。
对这些小企业来说，雇员很少，营业额较低,资金一般由较少的人提供,因此，通常由这些业主直接管理企业。
毕业论文外文翻译(中英文)
译文交通拥堵和城市交通系统的可持续发展摘要:城市化和机动化的快速增长,通常有助于城市交通系统的发展，是经济性，环境性和社会可持续性的体现,但其结果是交通量无情增加，导致交通拥挤。
道路拥挤定价已经提出了很多次，作为一个经济措施缓解城市交通拥挤，但还没有见过在实践中广泛使用，因为道路收费的一些潜在的影响仍然不明。
本文首先回顾可持续运输系统的概念,它应该满足集体经济发展,环境保护和社会正义的目标.然后,根据可持续交通系统的特点，使拥挤收费能够促进经济增长，环境保护和社会正义。
研究结果表明,交通拥堵收费是一个切实有效的方式，可以促进城市交通系统的可持续发展。
一、介绍城市交通是一个在世界各地的大城市迫切关注的话题。
随着中国的城市化和机动化的快速发展,交通拥堵已成为一个越来越严重的问题,造成较大的时间延迟,增加能源消耗和空气污染，减少了道路网络的可靠性．在许多城市,交通挤塞情况被看作是经济发展的障碍.我们可以使用多种方法来解决交通挤塞,包括新的基础设施建设，改善基础设施的维护和操作,并利用现有的基础设施,通过需求管理策略,包括定价机制,更有效地减少运输密度.交通拥堵收费在很久以前就已提出，作为一种有效的措施,来缓解的交通挤塞情况。
交通拥堵收费的原则与目标是通过对选择在高峰拥挤时段的设施的使用实施附加收费,以纾缓拥堵情况．转移非高峰期一些出行路线,远离拥挤的设施或高占用车辆，或完全阻止一些出行,交通拥堵收费计划将在节省时间和降低经营成本的基础上,改善空气中的质量，减少能源消耗和改善过境生产力。
此计划在世界很多国家和地方都有成功的应用。
继在2０世纪70年代初和8０年代中期挪威与新加坡实行收费环,在20０３年2月伦敦金融城推出了面积收费；直至现在,它都是已经开始实施拥挤收费的大都市圈中一个最知名的例子。
然而,交通拥堵收费由于理论和政治的原因未能在实践中广泛使用。
道路收费的一些潜在的影响尚不清楚,和城市发展的拥塞定价可持续性,需要进一步研究。
英语专业全英毕业论文(汉英公示语翻译)
本科毕业论文题目：On English Translation of ChinesePublic Signs 院（系）：外语系班级：英语级班姓名：学号：指导教师：教师职称：汉英公示语的翻译摘要公示语向来被称作“城市的脸孔"，是给所有到中国来的外国人士留下第一印象的中国名片。
然而，公示语翻译的错误比比皆是，这大大影响了公示语作用的发挥，削弱了我国的国际形象。
为了树立我国良好的国际形象，不断规范和完善城市公示语的翻译成为了一项亟待完成的工作。
基于以上原因，作者尝试从理论和实践的角度分析现今汉英公示语翻译中所存在的一些问题。
通过对大量标准以及问题公示语翻译的深入观察分析，作者对公示语的一般特征进行了总结并对公示语翻译中出现的问题进行了分类，从而在实践观察和对相关理论深入研究的基础上提出相应的翻译策略。
翻译并不仅仅是跨语言行为，它更是一种文化信息的传递。
公示语的翻译同样如此。
得体的公示语翻译不仅在语言上要无懈可击，在文化信息传递上也要雅俗共赏。
本文还对公示语的概念做出了解释，并根据目的需求与功能两种标准对公示语做了分类。
在介绍公示语的特征时，作者将其分为语言特征与功能特征，特征与分类不同，也决定了需要采取不同的翻译策略。
关键词：汉英翻译；公示语；问题；翻译策略On English Translation of Chinese PublicSignsAbstractPublic signs, which have alway s been referred to “face of city”, are the first impression of China for the people who come to China. However, the ubiquitous translation mistakes of public signs greatly undermine the international image of China. So,specificating and constantly perfecting the translation of public signs have become an urgent work in order to establish a good international image.The paper ventures an attempt to analyze the current problems existing in the C-E translation of public signs and to seek proper translational strategies both from the perspectives of theory and practice．By closely observing numerous samples of both standard and problematic translation of signs，the author manages to generalize the characteristics of public signs and to categorize the problems and mistakes in the current C-E translation of public signs．Then, proper translational strategies are proposed on the basis of in-depth study of relevant theories and keen observation of practice．Translation is not merely a cross-linguistic activity, but more of a transmission of cultural information．The translation of public signs is no exception．An appropriate translation of public sign should not only belinguistically correct, but also culturally acceptable．This paper expresses the meaning of the public signs and classify the signs according to the standards of objective demand and function. And the characteristics of the public signs are different studied from linguistic features and functional features,which determines to adopt different translation strategies.Key words: Chinese-English translation public sign problems translation strategyContents摘要 (I)Abstract (II)CHAPTER I Introduction (1)1.1 O bjective of the study (1)1.2 Significance of the study (1)1.3 Structure of the paper (2)CHAPTER II General Introduction to Public Signs (3)2.1 Definition of Public Signs (3)2.2 Functions of Public Signs (3)2.2.1 Directing function (4)2.2.2 Prompting function (4)2.2.3 Restricting function (4)2.2.4 Compelling function (5)CHAPTER III Analysis on Problems in C-E Translation of Public Signs (6)3.1 Linguistic translation problems (6)3.1.1 Spelling errors (6)3.1.2 Grammatical errors (6)3.1.3 Wrong dictions (7)3.2 Cultural translation problems (7)CHAPTER IV Strategies of C-E Public Signs Translation and Requirementfor Translator (9)4.1 Principles of C-E translation of Public Signs (9)4.1.1 Clearness (9)4.1.2 Conciseness (10)4.1.3 Simple words (10)4.2 Methods of C-E translation of Public S igns (11)4.2.1 Modification (11)4.2.2 Addition (11)4.2.3 Omission (12)4.2.4 Mutual transformation of affirmative and negativee xpressions (13)4.3 Requirement for the t ranslators (13)CHAPTER V Conclusion (15)Acknowledgements (16)Works Cited (17)CHAPTER I Introduction1.1Objective of the studyThe research objective of the study is to examine the translation problems in the Chinese-English public signs translation and further propose the translation strategies as well as principles suitable for specific groups.The studies begin with the careful and long period of observation of the problems existing in the public signs translation. On the basis of the classification of the translation errors proposed by Christiane Nord, the author aims at the most appropriate translation strategies for each type. With the examination of sufficient sources, the author finds that it is not difficult to eliminate the errors at linguistic level since the text of the public signs is less complex than documentary and other instrumental texts due to its conciseness and directness features (Ni 18).1.2 Significance of the studyPublic S igns affect people’s life in a tremendous way. When somebody smokes, it is the public sign that stops him. In fascinating and mysterious spots where we have never been to, it is the public sign that teaches us related knowledge. Foreign visitors from all walks of life，such as entrepreneurs，professors，students and tourists come to China for various purposes．But for most of them，they know little about Chinese．In this case，it is necessary to translate Chinese public signs into English for the convenience of these foreign visitors．In this case, a proper translation helps establish a good image of China and enhance the cultural communication.1.3 Structure of the paperThe paper is structured with five chapters：The first chapter is a general introduction to the thesis, including the objective of the study, the structure of the thesis and the significance of the study. The second chapter makes a general introduction to public sign, including the definition and functions of public sign. The third chapter focuses on the problems of C-E translation of public signs from linguistics and cultural perspectives. The fourth chapter deals with translation strategies of C-E public signs in connection with principles, methods and the standardization for the translators, including modification, addition, omission and mutual transformation of affirmative and negative expressions. And the fifth chapter draws a conclusion to the paper，in which the author appeals for translators and scholars to make contributions to the C-E translation of public signs．CHAPTER II General Introduction to Public Signs2.1 Definition of Public SignsPublic Signs，which are usually called“signs”，include public notices，advertisements，slogans and expressions on the public signs．Public signs refer to “signs” in English and are defined in different ways.Ac cording to Longman Dictionary of Contemporary English(1997)，a sign is a piece of paper, metal, or wood with words or a picture that gives information，warnings，or instructions.In that sense, public sign is the general terms for indicators，signs，traffic signs, posters, slogans, warning, short notices，short instructions，stickers，and are becoming the catch word and the buzzword．All in all, public signs are so widely used and played important roles in our daily life.2.2 Functions of Public SignsPublic signs are essential to the normal operation of the society and their influence is also visible in almost every aspect of our daily life．Sometimes，we have to admit that our lives cannot do without the proper guidance that public signs provide to us．However, what usually happens is that we are prone to be bewildered by various public signs and the enormous information they convey to us．Therefore, it would be necessary to classify the public signs in terms of their functions as well as the status of information that they deliver．2.2.1 Directing functionDirecting is the most basic function of public signs, t his type of public signs is used to give readers related information about what the institution is，what it deals with and what kind of service it can provide．For example:Take Away(外卖)，Gas Station(加油站),Emergency Exit(紧急出口),Business Hours(营业时间)，Pause(暂停)，Menu(菜单)，Airport Security(机场安检).From the examples above we may tell that the language and the tone of these public signs are generally neutral，reflecting no attitude towards receptors．Therefore，public signs of this kind are purely informative rather than vocative．2.2.2 Prompting functionPromoting signs are similar to the directive ones in their informative function. While the difference is the former ．carries the tone of warning，reminding the readers to pay some attention to certain things or activities．For example：Keep Clear(请保持清洁), Keep Silence(请保持安静),Wet Paint(油漆未干)，Fully Booked(客满)，Beware of Pickpockets(小心扒手)，Maximum Height(限高).2.2.3 Restricting functionPublic Signs with restricting function impose restriction or even prohibition on receptors.The language used in this kind of signs are simple and direct but are not in rude，tough or impolite way．We can list some of them as following：Pay In Cash(现金支付),Slow Out(减速慢行),Keep Silence(保持安静),30 Minutes Parking(限停30分钟),Seat By Number(对号入座), Stand In Line(排队等候).2.2.4 Compelling functionCompelling function is the strongest considerable mood.It is used to prohibit the readers to do something or must do something.The language used is usually forceful，with no possibility of making a compromise．The sign with this function which we mostly often see is“No Smoking禁止吸烟”，that is to say that smoking iscompletely forbidden．Imperative sentence is not enough to express this strong mood，usually, we use“No+…”form，for example，“No Food禁止携带食物”．More examples：Don’t Touch(禁止触摸),No Cameras(禁止拍照)，No Visitors(游客止步),No Trucks(卡车禁止通行),Dogs Not Allowed(禁止带狗入内).Translation of the public signs, translators not only need to grasp their function features since we use different mood to express different function,but also should keep their language features in mind during the translating.CHAPTER III Analysis on Problems in C-E Translation ofPublic Signs3.1 Linguistic translation problemsLinguistic translation errors are often due to deficiencies in the translator's source or target language competence (Nord 77).And in his book Pragmatics and English Language He Ziran explained that by making linguistic errors，the translators and interpreters fail to conform to the target language structures，instead they blindly translate the source text in their own language structures(157).Professor Wang Yinquan, classifies linguistic translation errors into: spelling mistakes, grammar mistakes and wrong diction (32).3.1.1 Spelling errorsSpelling errors are typical translation problems in bilingual public signs. The reasons for this type of errors attribute to the three factors: the incompetent language acquisition, the laziness of the translator when writing, the uncertainty of the correct spelling, among which the third type is most difficult to be identified. For example: 3.1.2 Grammatical errorsApart from spelling mistakes，many grammatical errors also occur in the translated signs．These errors appear in various forms，most of which result from the translator’s poor command of the English language or irresponsible working attitude．As a result，the translated public signs cannot be of any help to the target readers．Sometimes they may do damage the image of our city．For example: 室内停车场(Car Park)—It may be apparent to tell that the translator intends to use the word“park”as a noun to express the meaning of parking place for automobiles．However, as a noun the word actually means a public place wherepeople can entertain themselves with the landscape or public facilities in it．Therefore, it will be advisable to use the gerund form of the word “park”and translate it as“Indoor Parking”．3.1.3 Wrong dictionsWrong Dictions occur when t he translator doesn’t make right choices of words in the target culture that will lead to unsuccessful expression of the correct information to the target text receivers. In fact, many English words have more than one meaning. Sometimes one word used to describe the source culture may not be applicable in another situation and the diction is conditioned. The words chosen for each text might vary according to different semantic and syntactic features in different situations. For example:请勿采摘花朵--Please Don’t Pick Flowers. Here use“pick”to describe the gesture. In fact, there is a variety of expression in English corresponding with “摘”, of which one of the expressions is “pick”. But in the given circumstances, “pick”doesn’t equate with “摘”. “Pick”means to select among a variety of choices, but here the sender wants to persuade people not to pluck the flowers. The error is due to the confusion about the seemingly identical usage of one word.3.2 Cultural translation problemsAs we all know, people in different cultures may view the same thing in different ways and differ in the perspective of cognition．At the same time，they express the same idea in different way．As far as Chinese and English are concerned, culture differences are tremendous．Translation breaks down language barriers and thus realizes communication between cultures using different languages. In this sense, target readers approach to people of source culture whose beliefs, backgrounds, perception of the world are distinct from their own.For example:古装照相It is ancient to pack photo“古装照相”is a typical Chinese term. In English, people don’t have the correspondent term. According to the public signs translation convention, the signs which are composed of Chinese noun phrases are expected to have the same structure in English version, so the sentence is not correct in terms of the sentence structure. Also concerning the meaning of the sentence, it is wrongly translated that the foreigners can’t get the message which leads to the pragmatic failure of the assumed function. The correct version should be “Photos in ancient costume”.CHAPTER IV Strategies for C-E Public Signs Translation4.1 Principles of C-E translation of Public SignsAs we know, different functions need different language forms to convey and each language style possesses its special principles.Ni Chuanbin and Liu Zhi analyze the language principles of public signs in their essay“The Principles for C-E Translation of Public Signs and its Cases Study”，published in Shanghai Journal of Translators for Science and Technology(18)．Firstly, the signs are on a board，so the language on the signs should be in concise way due to the comparatively small space．Secondly, some public signs must draw the public’s attention at the first sight and the readers can catch its meaning very quickly and correctly, especially the traffic signs，such as“Abrupt Turn Left Ahead前方急转弯”，the applied words should be simple ones instead of rare ones．At last，the meaning of the signs should be clear and easy to read，the sign is set without ambiguity. So we can know the principles in details as following:4.1.1 ClearnessDue to the short time the target reader can spend on reading the signs the meaning of the signs should be clear and easy to be understood．As the target readers are the common people who have little knowledge related to the concerned topic，the signs should directly hit the point and there should exist no vagueness．“严禁客货混装Don’t put passengers and cargos together”. It is hazy and not clearness. So the sign“严禁客货混装”should be translated into“No passengers on Trucks”．The signs are set for the public and not every reader is professional，therefore when we translate signs，we should hit the point directly and clearly and should notjust talk around the bush.4.1.2 ConcisenessAccording to William Strunk，Jr．and E．B．White in 1979(Joan Pinkham)：“Vigorous writing is concise．A sentence should contain no unnecessary words，a paragraph no unnecessary sentences，for the same reason that a drawing should have no unnecessary lines and a machine no unnecessary parts．”It is also true of language of public signs．Usually, the readers for public signs just give a quick look at the board with signs on when they pass by．So the language on it need not be in a complete sentence，a phrase or just a word is enough，for example，“No Smoking禁止吸烟”，“Open正在营业”，we need not use sentences“Please do not smoke”an“We are on business”.4.1.3 Simple wordsPublic Signs are set for the public，target readers of this kind of materials are ordinary people，not only the native English speakers，but also other foreigners who know a little English and English is not his mother language，and target readers also include overseas Chinese who is not a English native speaker．If the English version is full of rare words and expression，it will cause a pragmatic failure of communication for public signs．There is always a small restaurant at the airport to provide fast food for the passengers，the English tablet should be“Snacks”instead of“Refection”，the later one is not often be used nowadays and we cannot find it in the dictionaries published in recent years．Take all another example，“景区环境卫生，需要您的维护”，should we translate it into“Environmental Sanitation of the Scenic Spot Needs Your Conserve”? The words“sanitation”and“environmental”are not familial words for the public，we had better use“Keep Clear”or“No Littering”．From the above，in order to make target readers catch the meaning at first glance，we should use the concise，clear, simple words and expressions in C-E translation of public signs．4.2 Strategies of C-E translation of Public Signs4.2.1 ModificationGenerally speaking, it is always the case that the reader in the culture of the target language may not share the cultural background of the source language．Therefore，when dealing with culture-loaded words and idioms，the translator sometimes has to make cultural modification so as to generate the same feedback from the target text reader with that of the source text reader, and as for the translation of public signs, it is no exception．For examples：西湖的虎跑泉—Tiger Running Spring, in this public sign,the translator obviously take the actual meaning of the sign for granted by translating the word“虎跑”as“tiger running”which means that a tiger runs for the spring．4.2.2 AdditionSome public signs，especially signs at scenic spots，tend to include dynasties，legends or other cultural elements，while most foreign visitors lack the background knowledge of China．If the public signs are translated literally, the English versions may confuse the target readers．Thus we should adopt the translation strategy of addition to supply necessary information on the basis of accurate comprehension of the original public signs．For example：谢绝游客入内Closed To Visitors禁止在墙上涂写No Scribbling On The Wall4.2.3 OmissionDue to different aesthetic standards and cultures，Chinese writing tends to include flowery words，four-word phrases or some culture elements which are special to the Chinese culture．However, English writing pursues clear and simple expressions．In How to Help Foreigners Know China，Duan Liancheng holds a view that with the development of tourism in recent years，large numbers of brochures pamphlets and pictorials have been published for foreign tourists．A common weakness of these materials is full of flowery words and cultural elements of China which may confuse the target readers (Duan 286). So the translator should omit some adjectives or cultural elements which may pose barriers to the target readers．Then the English version will be easily understood by them．For example：1.Source Text：慢速行驶Version A：You must drive slowly．Version B：Drive slowly2.Source Text：前方学校Version A：There is a school ahead．Version B：School Ahead4.2.4 Mutual transformation of affirmative and negative expressionsMutual transformation of affirmative and negative expressions is a common strategy in translating the text of one language to the other．It is especially useful for transcending the translational difficulties due to different ways or habits of expressing ideas in Chinese and English．In translating public signs，mutual transformation of affirmative and negativeexpressions is necessary as well．In western countries especially in English—speaking countries，people tend to avoid using negative expressions in public literatures as much as possible in case that unpleasant emotion or feeling would be aroused on the part of the receptor．However, because of the difference in cultural values,negative expressions are more frequently used in Chinese public signs．Therefore，according to the theory of cultural translation, we should adopt the translational method of“Domestication”．For example: “社会车辆禁止入内”，it is a kind of negative expression in Chinese language. While it should be translated into “Staff Only” in English, it is affirmative.4.3 Requirement for the translatorsThe C-E translation of public signs is by no means an easy job and it requires that a translator be serious and accountable in attitude, and proficient in both the source and the target languages at the same time．A good translator should always bear in mind the features and characteristics of public signs.Only if the translators acquire the expertise in the source and target languages as well as the source and target cultures can they produce qualified versions. In addition, as for the making process of signs, the local governments should choose reliable and efficient sign-making units by means of bidding to undertake the job.And the translation should be tested in the foreigners to ensure the acceptability.Then a supervision organization in charge of public signs should be established to make sure that some common English versions are accurate and unified.CHAPTER V ConclusionBased on the previous discussions and analyses, the major findings of this study can be summarized as follow:Firstly, the linguistic translation problems account for the reasons for spelling, grammatical and wrong dictions problems. Translators should improve their language acquisition in dealing with the problems.Secondly, as to cultural problems, the translators are advised to adopt communicative translation. To be more specific, the translation strategies are adaptation, restructuring, semi-literal translation, etc.Thirdly, the C-E translation involves the principles and the methods. The principles include three points of clearness, conciseness and simple words. The translation takes place in a given situation or in another sense, the methods of C-E translation of public signs should be divided into four: modification, addition, omission and mutual transformation of affirmative and negative expressions.Actually, the problems of the translation of public signs are far more complicated than the thesis．The problems that have been discussed and proposed with strategies to are just a tiny tip of the whole iceberg．With the development of the society, it is sure that more and more public signs will come out by taking various forms，and new problems in translating them will turn up．Therefore，the classification of public signs and mistranslation, as well as the strategies for the betterment of the current status of sign translation, although the author attempts to let them be, are not all-inclusive and universally accurate. It is a long and hard way for us to go.AcknowledgementsI would like to express my heartfelt thanks to those who offered me their sincere support and encouragement in the process of my thesis writing．First of all, I’d like to give my sincere thanks to my teacher, Kangbing. She has given me valuable instructions on my study. Whenever I need her help, she always enthusiastically offers me. During the process of the completion of the thesis, from the researches chosen to be analyzed to the final composition, her patient and helpful instructions have benefited me a great deal. Her strict requirements have enabled me to learn how to do research work, and her kind encouragement have been supporting me to the end.Second, my true thanks also go to all the teachers who guide me in the field of business English.Finally, my family and friends give me great encouragement and support during the composition of the thesis. I’d like to send them my heartfelt thanks too.Work CitedBaker, Mona. 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建筑学Modern-Architecture现代建筑大学毕业论文外文文献翻译及原文
建筑学Modern-Architecture现代建筑⼤学毕业论⽂外⽂⽂献翻译及原⽂毕业设计（论⽂）外⽂⽂献翻译⽂献、资料中⽂题⽬：现代建筑⽂献、资料英⽂题⽬：Modern Architecture⽂献、资料来源：⽂献、资料发表（出版）⽇期：院（部）：专业：班级：姓名：学号：指导教师：翻译⽇期： 2017.02.14建筑学毕业设计的外⽂⽂献及译⽂⽂献、资料题⽬：《Advanced Encryption Standard》⽂献、资料发表（出版）⽇期：2004.10.25外⽂⽂献：Modern ArchitectureModern architecture, not to be confused with 'contemporary architecture', is a term given to a number of building styles with similar characteristics, primarily the simplification of form and the elimination of ornament. While the style was conceived early in the 20th century and heavily promoted by a few architects, architectural educators and exhibits, very few Modern buildings were built in the first half of the century. For three decades after the Second World War, however, it became the dominant architectural style for institutional and corporate building.1. OriginsSome historians see the evolution of Modern architecture as a social matter, closely tied to the project of Modernity and hence to the Enlightenment, a result of social and political revolutions.Others see Modern architecture as primarily driven by technological and engineering developments, and it is true that the availability of new building materials such as iron, steel, concrete and glass drove the invention of new building techniques as part of the Industrial Revolution. In 1796, Shrewsbury mill owner Charles Bage first used his ‘fireproof’ design, which relied on cast iron and brick with flag stone floors. Such construction greatly strengthened the structure of mills, which enabled them to accommodate much bigger machines. Due to poor knowledge of iron's properties as a construction material, a number of early mills collapsed. It was not until the early 1830s that Eaton Hodgkinson introduced the section beam, leading to widespread use of iron construction, this kind of austere industrial architecture utterly transformed the landscape of northern Britain, leading to the description, "Dark satanic mills" of places like Manchester and parts of West Yorkshire. The Crystal Palace by Joseph Paxton at the Great Exhibition of 1851 was an early example of iron and glass construction; possibly the best example is the development of the tall steel skyscraper in Chicago around 1890 by William Le Baron Jenney and Louis Sullivan. Early structures to employ concrete as the chief means of architectural expression (rather than for purely utilitarian structure) include Frank Lloyd Wright's Unity Temple, built in 1906 near Chicago, and Rudolf Steiner's Second Goetheanum, built from1926 near Basel, Switzerland.Other historians regard Modernism as a matter of taste, a reaction against eclecticism and the lavish stylistic excesses of Victorian Era and Edwardian Art Nouveau.Whatever the cause, around 1900 a number of architects around the world began developing new architectural solutions to integrate traditional precedents (Gothic, for instance) with new technological possibilities. The work of Louis Sullivan and Frank Lloyd Wright in Chicago, Victor Horta in Brussels, Antoni Gaudi in Barcelona, Otto Wagner in Vienna and Charles Rennie Mackintosh in Glasgow, among many others, can be seen as a common struggle between old and new.2. Modernism as Dominant StyleBy the 1920s the most important figures in Modern architecture had established their reputations. The big three are commonly recognized as Le Corbusier in France, and Ludwig Mies van der Rohe and Walter Gropius in Germany. Mies van der Rohe and Gropius were both directors of the Bauhaus, one of a number of European schools and associations concerned with reconciling craft tradition and industrial technology.Frank Lloyd Wright's career parallels and influences the work of the European modernists, particularly via the Wasmuth Portfolio, but he refused to be categorized with them. Wright was a major influence on both Gropius and van der Rohe, however, as well as on the whole of organic architecture.In 1932 came the important MOMA exhibition, the International Exhibition of Modern Architecture, curated by Philip Johnson. Johnson and collaborator Henry-Russell Hitchcock drew together many distinct threads and trends, identified them as stylistically similar and having a common purpose, and consolidated them into the International Style.This was an important turning point. With World War II the important figures of the Bauhaus fled to the United States, to Chicago, to the Harvard Graduate School of Design, and to Black Mountain College. While Modern architectural design never became a dominant style in single-dwelling residential buildings, in institutional and commercial architecture Modernism became the pre-eminent, and in the schools (for leaders of the profession) the only acceptable, design solution from about 1932 to about 1984.Architects who worked in the international style wanted to break with architectural tradition and design simple, unornamented buildings. The most commonly used materials are glass for the facade, steel for exterior support, and concrete for the floors and interior supports; floor plans were functional and logical. The style became most evident in the design of skyscrapers. Perhaps its most famous manifestations include the United Nations headquarters (Le Corbusier, Oscar Niemeyer, Sir Howard Robertson), the Seagram Building (Ludwig Mies van der Rohe), and Lever House (Skidmore, Owings, and Merrill), all in New York. A prominent residential example is the Lovell House (Richard Neutra) in Los Angeles.Detractors of the international style claim that its stark, uncompromisingly rectangular geometry is dehumanising. Le Corbusier once described buildings as "machines for living", but people are not machines and it was suggested that they do not want to live in machines. Even Philip Johnson admitted he was "bored with the box." Since the early 1980s many architects have deliberately sought to move away from rectilinear designs, towards more eclectic styles. During the middle of the century, some architects began experimenting in organic forms that they felt were more human and accessible. Mid-century modernism, or organic modernism, was very popular, due to its democratic and playful nature. Alvar Aalto and Eero Saarinen were two of the most prolific architects and designers in this movement, which has influenced contemporary modernism.Although there is debate as to when and why the decline of the modern movement occurred, criticism of Modern architecture began in the 1960s on the grounds that it was universal, sterile, elitist and lacked meaning. Its approach had become ossified in a "style" that threatened to degenerate into a set of mannerisms. Siegfried Giedion in the 1961 introduction to his evolving text, Space, Time and Architecture (first written in 1941), could begin "At the moment a certain confusion exists in contemporary architecture, as in painting; a kind of pause, even a kind of exhaustion." At the Metropolitan Museum of Art, a 1961 symposium discussed the question "Modern Architecture: Death or Metamorphosis?" In New York, the coup d'état appeared to materialize in controversy around the Pan Am Building that loomed over Grand Central Station, taking advantage of the modernist real estate concept of "air rights",[1] In criticism by Ada Louise Huxtable and Douglas Haskell it was seen to "sever" the Park Avenue streetscape and "tarnish" the reputations of its consortium of architects: Walter Gropius, Pietro Belluschi and thebuilders Emery Roth & Sons. The rise of postmodernism was attributed to disenchantment with Modern architecture. By the 1980s, postmodern architecture appeared triumphant over modernism, including the temple of the Light of the World, a futuristic design for its time Guadalajara Jalisco La Luz del Mundo Sede International; however, postmodern aesthetics lacked traction and by the mid-1990s, a neo-modern (or hypermodern) architecture had once again established international pre-eminence. As part of this revival, much of the criticism of the modernists has been revisited, refuted, and re-evaluated; and a modernistic idiom once again dominates in institutional and commercial contemporary practice, but must now compete with the revival of traditional architectural design in commercial and institutional architecture; residential design continues to be dominated by a traditional aesthetic.中⽂译⽂：现代建筑现代建筑,不被混淆与'当代建筑' , 是⼀个词给了⼀些建筑风格有类似的特点, 主要的简化形式,消除装饰等. 虽然风格的设想早在20世纪,并⼤量造就了⼀些建筑师、建筑教育家和展品,很少有现代的建筑物,建于20世纪上半叶. 第⼆次⼤战后的三⼗年, 但最终却成为主导建筑风格的机构和公司建设.1起源⼀些历史学家认为进化的现代建筑作为⼀个社会问题, 息息相关的⼯程中的现代性,从⽽影响了启蒙运动,导致社会和政治⾰命.另⼀些⼈认为现代建筑主要是靠技术和⼯程学的发展, 那就是获得新的建筑材料,如钢铁, 混凝⼟和玻璃驱车发明新的建筑技术,它作为⼯业⾰命的⼀部分. 1796年, shrewsbury查尔斯bage⾸先⽤他的'⽕'的设计, 后者则依靠铸铁及砖与⽯材地板. 这些建设⼤⼤加强了结构,使它们能够容纳更⼤的机器. 由于作为建筑材料特性知识缺乏,⼀些早期建筑失败. 直到1830年初,伊顿Hodgkinson预计推出了型钢梁, 导致⼴泛使⽤钢架建设，⼯业结构完全改变了这种窘迫的⾯貌,英国北部领导的描述, "⿊暗魔⿁作坊"的地⽅如曼彻斯特和西约克郡. ⽔晶宫由约瑟夫paxton的重⼤展览, 1851年,是⼀个早期的例⼦,钢铁及玻璃施⼯; 可能是⼀个最好的例⼦,就是1890年由William乐男爵延长和路易沙利⽂在芝加哥附近发展的⾼层钢结构摩天楼. 早期结构采⽤混凝⼟作为⾏政⼿段的建筑表达(⽽⾮纯粹功利结构) ,包括建于1906年在芝加哥附近,劳埃德赖特的统⼀宫, 建于1926年瑞⼠巴塞尔附近的鲁道夫斯坦纳的第⼆哥特堂,.但⽆论原因为何, 约有1900多位建筑师,在世界各地开始制定新的建筑⽅法,将传统的先例(⽐如哥特式)与新的技术相结合的可能性.路易沙利⽂和赖特在芝加哥⼯作,维克多奥尔塔在布鲁塞尔,安东尼⾼迪在巴塞罗那, 奥托⽡格纳和查尔斯景mackintosh格拉斯哥在维也纳,其中之⼀可以看作是⼀个新与旧的共同⽃争.2现代主义风格由1920年代的最重要⼈物,在现代建筑⾥确⽴了⾃⼰的名声. 三个是公认的柯布西耶在法国, 密斯范德尔德罗和⽡尔特格罗⽪乌斯在德国. 密斯范德尔德罗和格罗⽪乌斯为董事的包豪斯, 其中欧洲有不少学校和有关团体学习调和⼯艺和传统⼯业技术.赖特的建筑⽣涯中,也影响了欧洲建筑的现代艺术,特别是通过⽡斯穆特组合但他拒绝被归类与他们. 赖特与格罗⽪乌斯和Van der德罗对整个有机体系有重⼤的影响.在1932年来到的重要moma展览,是现代建筑艺术的国际展览,艺术家菲利普约翰逊. 约翰逊和合作者亨利-罗素阁纠集许多鲜明的线索和趋势, 内容相似,有⼀个共同的⽬的,巩固了他们融⼊国际化风格这是⼀个重要的转折点. 在⼆战的时间包豪斯的代表⼈物逃到美国,芝加哥，到哈佛⼤学设计⿊⼭书院. 当现代建筑设计从未成为主导风格单⼀的住宅楼，在成为现代卓越的体制和商业建筑, 是学校(专业领导)的唯⼀可接受的, 设计解决⽅案,从约1932年⾄约1984年.那些从事国际风格的建筑师想要打破传统建筑和简单的没有装饰的建筑物。
会计学毕业论文中英文资料外文翻译文献
会计学中英文资料外文翻译外文原文Title:Future of SME finance（Background – the environment for SME finance has changedFuture economic recovery will depend on the possibility of Crafts, Trades and SMEs to exploit their potential for growth and employment creation.SMEs make a major contribution to growth and employment in the EU and are at the heart of the Lisbon Strategy, whose main objective is to turn Europe into the most competitive and dynamic knowledge-based economy in the world. However, the ability of SMEs to grow depends highly on their potential to invest in restructuring, innovation and qualification. All of these investments need capital and therefore access to finance.Against this background the consistently repeated complaint of SMEs about their problems regarding access to finance is a highly relevant constraint that endangers the economic recovery of Europe.Changes in the finance sector influence the behavior of credit institutes towards Crafts, Trades and SMEs. Recent and ongoing developments in the banking sector add to the concerns of SMEs and will further endanger their access to finance. The main changes in the banking sector which influence SME finance are:•Globalization and internationalization have increased the competition and the profit orientation in the sector;•worsening of the economic situations in some institutes (burst of the ITC bubble, insolvencies) strengthen the focus on profitability further;•Mergers and restructuring created larger structures and many local branches, which had direct and personalized contacts with small enterprises, were closed;•up-coming implementation of new capital adequacy rules (Basel II) will also change SME business of the credit sector and will increase its administrative costs;•Stricter interpretation of State-Aide Rules by the European Commission eliminates the support of banks by public guarantees; many of the effected banks arevery active in SME finance.All these changes result in a higher sensitivity for risks and profits in the finance sector.The changes in the finance sector affect the accessibility of SMEs to finance.Higher risk awareness in the credit sector, a stronger focus on profitability and the ongoing restructuring in the finance sector change the framework for SME finance and influence the accessibility of SMEs to finance. The most important changes are: •In order to make the higher risk awareness operational, the credit sector introduces new rating systems and instruments for credit scoring;•Risk assessment of SMEs by banks will force the enterprises to present more and better quality information on their businesses;•Banks will try to pass through their additional costs for implementing and running the new capital regulations (Basel II) to their business clients;•due to the increase of competition on interest rates, the bank sector demands more and higher fees for its services (administration of accounts, payments systems, etc.), which are not only additional costs for SMEs but also limit their liquidity;•Small enterprises will lose their personal relationship with decision-makers in local branches –the credit application process will become more formal and anonymous and will probably lose longer;•the credit sector will lose more and more its “public function” to provide access to finance for a wide range of economic actors, which it has in a number of countries, in order to support and facilitate economic growth; the profitability of lending becomes the main focus of private credit institutions.All of these developments will make access to finance for SMEs even more difficult and / or will increase the cost of external finance. Business start-ups and SMEs, which want to enter new markets, may especially suffer from shortages regarding finance. A European Code of Conduct between Banks and SMEs would have allowed at least more transparency in the relations between Banks and SMEs and UEAPME regrets that the bank sector was not able to agree on such a commitment.Towards an encompassing policy approach to improve the access of Crafts, Trades and SMEs to financeAll analyses show that credits and loans will stay the main source of finance forthe SME sector in Europe. Access to finance was always a main concern for SMEs, but the recent developments in the finance sector worsen the situation even more. Shortage of finance is already a relevant factor, which hinders economic recovery in Europe. Many SMEs are not able to finance their needs for investment.Therefore, UEAPME expects the new European Commission and the new European Parliament to strengthen their efforts to improve the framework conditions for SME finance. Europe’s Crafts, Trades and SMEs ask for an encompassing policy approach, which includes not only the conditions for SMEs’ access to lending, but will also strengthen their capacity for internal finance and their access to external risk capital.From UEAPME’s point of view such an encompassing approach should be based on three guiding principles:•Risk-sharing between private investors, financial institutes, SMEs and public sector;•Increase of transparency of SMEs towards their external investors and lenders;•improving the regulatory environment for SME finance.Based on these principles and against the background of the changing environment for SME finance, UEAPME proposes policy measures in the following areas:1. New Capital Requirement Directive: SME friendly implementation of Basel IIDue to intensive lobbying activities, UEAPME, together with other Business Associations in Europe, has achieved some improvements in favour of SMEs regarding the new Basel Agreement on regulatory capital (Basel II). The final agreement from the Basel Committee contains a much more realistic approach toward the real risk situation of SME lending for the finance market and will allow the necessary room for adaptations, which respect the different regional traditions and institutional structures.However, the new regulatory system will influence the relations between Banks and SMEs and it will depend very much on the way it will be implemented into European law, whether Basel II becomes burdensome for SMEs and if it will reduce access to finance for them.The new Capital Accord form the Basel Committee gives the financial marketauthorities and herewith the European Institutions, a lot of flexibility. In about 70 areas they have room to adapt the Accord to their specific needs when implementing it into EU law. Some of them will have important effects on the costs and the accessibility of finance for SMEs.UEAPME expects therefore from the new European Commission and the new European Parliament:•The implementation of the new Capital Requirement Directive will be costly for the Finance Sector (up to 30 Billion Euro till 2006) and its clients will have to pay for it. Therefore, the implementation – especially for smaller banks, which are often very active in SME finance –has to be carried out with as little administrative burdensome as possible (reporting obligations, statistics, etc.).•The European Regulators must recognize traditional instruments for collaterals (guarantees, etc.) as far as possible.•The European Commission and later the Member States should take over the recommendations from the European Parliament with regard to granularity, access to retail portfolio, maturity, partial use, adaptation of thresholds, etc., which will ease the burden on SME finance.2. SMEs need transparent rating proceduresDue to higher risk awareness of the finance sector and the needs of Basel II, many SMEs will be confronted for the first time with internal rating procedures or credit scoring systems by their banks. The bank will require more and better quality information from their clients and will assess them in a new way. Both up-coming developments are already causing increasing uncertainty amongst SMEs.In order to reduce this uncertainty and to allow SMEs to understand the principles of the new risk assessment, UEAPME demands transparent rating procedures –rating procedures may not become a “Black Box” for SMEs:•The bank should communicate the relevant criteria affecting the rating of SMEs.•The bank should inform SMEs about its assessment in order to allow SMEs to improve.The negotiations on a European Code of Conduct between Banks and SMEs , which would have included a self-commitment for transparent rating procedures by Banks, failed. Therefore, UEAPME expects from the new European Commission andthe new European Parliament support for:•binding rules in the framework of the new Capital Adequacy Directive, which ensure the transparency of rating procedures and credit scoring systems for SMEs;•Elaboration of national Codes of Conduct in order to improve the relations between Banks and SMEs and to support the adaptation of SMEs to the new financial environment.3. SMEs need an extension of credit guarantee systems with a special focus on Micro-LendingBusiness start-ups, the transfer of businesses and innovative fast growth SMEs also depended in the past very often on public support to get access to finance. Increasing risk awareness by banks and the stricter interpretation of State Aid Rules will further increase the need for public support.Already now, there are credit guarantee schemes in many countries on the limit of their capacity and too many investment projects cannot be realized by SMEs.Experiences show that Public money, spent for supporting credit guarantees systems, is a very efficient instrument and has a much higher multiplying effect than other instruments. One Euro form the European Investment Funds can stimulate 30 Euro investments in SMEs (for venture capital funds the relation is only 1:2).Therefore, UEAPME expects the new European Commission and the new European Parliament to support:•The extension of funds for national credit guarantees schemes in the framework of the new Multi-Annual Programmed for Enterprises;•The development of new instruments for securitizations of SME portfolios;•The recognition of existing and well functioning credit guarantees schemes as collateral;•More flexibility within the European Instruments, because of national differences in the situation of SME finance;•The development of credit guarantees schemes in the new Member States;•The development of an SBIC-like scheme in the Member States to close the equity gap (0.2 – 2.5 Mio Euro, according to the expert meeting on PACE on April 27 in Luxemburg).•the development of a financial support scheme to encourage the internalizations of SMEs (currently there is no scheme available at EU level:termination of JOP, fading out of JEV).4. SMEs need company and income taxation systems, which strengthen their capacity for self-financingMany EU Member States have company and income taxation systems with negative incentives to build-up capital within the company by re-investing their profits. This is especially true for companies, which have to pay income taxes. Already in the past tax-regimes was one of the reasons for the higher dependence of Europe’s SMEs on bank lending. In future, the result of rating will also depend on the amount of capital in the company; the high dependence on lending will influence the access to lending. This is a vicious cycle, which has to be broken.Even though company and income taxation falls under the competence of Member States, UEAPME asks the new European Commission and the new European Parliament to publicly support tax-reforms, which will strengthen the capacity of Crafts, Trades and SME for self-financing. Thereby, a special focus on non-corporate companies is needed.5. Risk Capital – equity financingExternal equity financing does not have a real tradition in the SME sector. On the one hand, small enterprises and family business in general have traditionally not been very open towards external equity financing and are not used to informing transparently about their business.On the other hand, many investors of venture capital and similar forms of equity finance are very reluctant regarding investing their funds in smaller companies, which is more costly than investing bigger amounts in larger companies. Furthermore it is much more difficult to set out of such investments in smaller companies.Even though equity financing will never become the main source of financing for SMEs, it is an important instrument for highly innovative start-ups and fast growing companies and it has therefore to be further developed. UEAPME sees three pillars for such an approach where policy support is needed:Availability of venture capital•The Member States should review their taxation systems in order to create incentives to invest private money in all forms of venture capital.•Guarantee instruments for equity financing should be further developed.Improve the conditions for investing venture capital into SMEs•The development of secondary markets for venture capital investments inSMEs should be supported.•Accounting Standards for SMEs should be revised in order to ease transparent exchange of information between investor and owner-manager.Owner-managers must become more aware about the need for transparency towards investors•SME owners will have to realise that in future access to external finance (venture capital or lending) will depend much more on a transparent and open exchange of information about the situation and the perspectives of their companies.•In order to fulfil the new needs for transparency, SMEs will have to use new information instruments (business plans, financial reporting, etc.) and new management instruments (risk-management, financial management, etc.).外文资料翻译题目：未来的中小企业融资背景：中小企业融资已经改变未来的经济复苏将取决于能否工艺品，贸易和中小企业利用其潜在的增长和创造就业。
毕业设计论文 电子秤 中英文 外文资料 文献 翻译
外文参考资料二：Abstract: In order to solve the weight problem often encountered in measuring the low-mass objects in the trade and daily life of the modern business, the design of a new pocket-sized electronic scales. This pocket-sized electronic scales Force Sensor gravity signals into electrical signals to measure, and measuring the results of the digital display. The pocket-sized electronic scales with a small size, light weight, easy to carry, intuitive display, measurement and high precision; complex structure, the cost disadvantages. This article focuses on the load cell works, error compensation, the main parameters of selection. And the technical and economic analysis.Keywords: pocket-sized electronic scales; weighing; sensor; error compensationCLC number: TH715. 1] sign code: A Article ID: 100 522 895 (2007) 022*******1 A needs analysisIn modern commerce and trade and everyday life, often encounter the problem of measuring the weight of the low-mass objects. Although the traditional steelyard can solve this problem, but inconvenient to carry, the efficiency is not high, the display is not intuitive and low measurement accuracy; mechanical spring balance can solve this problem, but the inertia inherent low frequency, high sensitivity, measurement accuracy is not high. With the progress and update of the micro-computer technology, integrated circuit technology, sensor technology, electronic scales rapiddevelopment, it has a responsive, high accuracy, fully functional, the display is intuitive, compact, easy to use and so on.For these reasons, in order to solve the low-mass objects weighing problem, if a small size, light weight, portable, digital display electronic scales, will be popular. Discussed below, that is, the scope of a weighing 5 kg compact electronic scales.2 DesignThe principle of the structure of the pocket-sized electronic scales shown in Figure 1. The main task is to design compact electronic scales weighing the choice of the force sensors. Dynamometer sensor types to achieve the weighing and digital display, the key is to want to force (gravity) signals into electrical signals to measure method is mainly divided into two categories: one is the direct method, namely the use of pressure magnetic sensor, piezoelectric sensor, Piezoresistive sensors directly to the force signal converted into electrical signals; the other is the indirect method, the elastic element as the sensor will pull, pressure changes in strain, displacement, or frequency, and then strain sensors, displacement sensors, or frequency sensor strain, displacement or frequency changes for power. Comprehensive comparison of a variety of sensors, use the indirect method of strain gauge force transducer.Pocket-sized electronic scale structural principle:Sensor → amplifier → CPU→ display → AöD converter3 sensor device design3.1 worksThe working principle of the strain gauge force transducer strain gauge pasted into force, force-sensitive elasticelement, the corresponding strain when the elastic element force deformation, the strain gauge into a resistance change, which led to the voltage measuring circuit changes by measuring the output voltage value, and then through the conversion can be obtained by the measurement of body weight. Since the pocket-sized electronic scales require small size, weighing in scope, precision and angle even consistency, sensor and display integration, it is selected parallel to the two holes cantilever beam strain gauge load-bearing sensor. Its characteristics are: high precision, ease of processing, simple and compact structure, strong resistance to partial load, high natural frequency.Strain gauge choice of a metal palisade metal mooring paste on the insulating substrate parked strain gages, mechanical strain resistance strain gauge feelings generally 10 - 10 - 2mm, the resistance rate of change of the attendant about 10 - 6 10 - 2 orders of magnitude, such a small change in resistance measured using the general resistance of the instrument is hard to measure out, you must use some form of measurement.Circuit into small changes in resistance rates to changes in voltage or current, in order to secondary instrument display. Bridge measurement circuit to meet this requirement. In the load cell, R 1, R 2, R 3, R 44 strain gauge resistor bridge measurement circuit shown in Figure 3. R m is the temperature compensation resistor, e is the excitation voltage, V is the output voltage.外文参考资料三：The load cell is a quality signal into a measurable electrical signal outputdevice. Must consider the actual working environment of the sensor which sensor Yin, this is essential for the correct selection of the load cell, and it is related to the sensor can work as well as its safety and service life, and the whole weighing the reliability and safety sex. On the basic concepts and methods of evaluation of the major technical indicators of the load cell, the new and old GB qualitative differences.The traditional concept, the load sensor weighing sensors, force sensors, collectively referred to using a single parameter to evaluate its measurement properties. Old GB will be completely different application objects and the use of environmental conditions "weighing" and "measured force" two sensors into one to consider, not given to distinguish between the test and evaluation methods. Old GB total of 21 indicators, were tested at room temperature; and non-linearity, hysteresis error, repeatability error, creep, the additional error of the zero temperature and the maximum error in the six indicators of the rated output additional temperature error, to determine said The level of accuracy of the weight sensor, respectively 0.02,0.03,0.05 said.Proportion to convert the output signal can be measured. Taking into account the different place of use of the acceleration due to gravity and air buoyancy on the conversion, the main performance indicators of the load cell linearity error, hysteresis error, repeatability error, creep, zero-temperature characteristics and temperature sensitivity characteristics. In a variety of weighing and measuring the quality of the system, usually the integrated error accuracy of the integrated control sensors, and integrated error band or scale error band (Figure 1) linked so that selection corresponds to a certain accuracy weighing weighing sensors. International Organization of Legal Metrology(OIML) requirements, sensor error with total weighing instrument error δ with Δ of 70% of the load cell linearity error, hysteresis error within the specified temperature range due to the effect of temperature on the sensitivity of the error the sum can not exceed the error band of δ. This allows the manufacturer of the components that make up the total measurement error adjustment to obtain the desired accuracy.The load cell conversion method is divided into photoelectric, hydraulic, electromagnetic force type, capacitive, magnetic poles change the form of vibratory gyroscope ceremony, resistance strain type, to the most extensive use of resistance strain.Electromagnetic force sensorIt uses a load-bearing stage load and the principle of electromagnetic force Equilibrium (Figure 5). Put the loading stage, the measured object at one end of the lever upward tilt; photoelectric detect the tilt signal, amplified into the coil, the electromagnetic force, so that the lever to return to equilibrium. Currents produce electromagnetic counterweight digital converter, you can determine the quality of the measured object. The electromagnetic force sensor accuracy, up to 1/2000 ~ 1/60000, but the weighing range is only tens of mg to 10 kg.Capacitive sensorsItcapacitor oscillator circuit of the oscillation frequency f and the plate spacing d is directly proportional relationship between the work (Figure 6). There are two plates, one fixed and the other one can move. Bearing load measured object, the leaf spring deflection, the distance between the twoplates changes, the oscillation frequency of the circuit also changes. The measured frequency change can be calculated to the quality of the load-bearing stage, the measured object. Capacitive sensor power consumption, low cost, accuracy of 1/200 to 1/500.Pole change the form of sensorFerromagneticcomponents in the measured object gravity under mechanical deformation, internal stress and cause changes in permeability, and also changes so that the induced voltage of the secondary coil wound on both sides of the ferromagnetic component (pole). Measure the voltage variation can be calculated added to the force on the pole, and then determine the quality of the measured object. Pole to change the form of sensor accuracy is not high, usually 1/100, applicable to the large tonnage weighing, weighing ranging from tens to tens of thousands of kilograms.Vibration sensorThe force of the elastic element, the natural vibration frequency of the force is proportional to the square root of. Measure the natural frequency changes, you can find the measured object role in the elastic component of the force, and then calculate the quality. The vibration sensor vibrating wire and tuning fork.The elastic component of the vibrating wire sensor string wire. When the load-bearing stage, plus the measured object, the intersection of the V-shaped string wire is pulled down, and left strings of tension increases, the right string tension decreases. The natural frequency of the two strings of different changes. Calculate the frequency difference between the two strings, you can find the quality of the measured object. The higher the accuracy of the vibrating wire sensor, up to 1/1000 ~ 1/10000, weighing 100 g to hundreds of kilograms, but the structure is complex anddifficult process, and high cost.The elastic component of the tuning fork sensor is a tuning fork. Fixed tuning fork end of the piezoelectric element, the natural frequency of oscillation of a tuning fork, it can be measured oscillation frequency. When the load-bearing stage and the measured object, the tuning fork direction of tensile force while the increase in natural frequency, increasing levels of applied force is proportional to the square root. Measure the changes of natural frequency can be calculated heavy loads imposed on the tuning fork on the force, and then calculate the quality of heavy objects. The tuning fork sensor power consumption, measurement accuracy up to 1/10000 to 1/200 000, weighing range of 500g ~ 10kg.外文参考文献中文翻译参考资料二：摘要: 为解决现代商业贸易和日常生活中经常遇到的测量小质量物体的重量问题, 介绍了一种新型的袖珍式电子秤的设计。
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外 文 资 料 译 文 半固态加工对灰铸铁的凝固组织和力学性能的影响
摘要 金属的半固态加工正在成为一种生产球状结构和高品质铸件的创新技术。本文是针对半固态加工（采用冷却板技术）对灰铸铁的微观结构和强度影响效果的研究。试验采用是碳当量为3.59%的亚共晶灰铸铁。结果表明，随着固相分数的增加微观结构变得更圆更好。增加初生固相分数能够增加过冷度并改变石墨形态。与普通灰铸铁相比，半固态加工成型的灰铸铁的抗拉强度相当的高。其拉伸强度和伸长率的都取决于固相分数。据发现，在半固态加工中，石墨形态（尺寸和类型）、初生固相集聚和切割石墨网络对以上两种性能都有很大的影响。据观察，总断裂强度取决于石墨形态以及组织的排列方式，而这又主要取决于固相分数。固相分数的增加可以增加硬度值，这是由于半固态加工使其组织均匀化。
关键词：半固态成形，灰铸铁，微观组织，力学性能，石墨形态，冷却盘 1 前言 灰铸铁含有片状石墨分散在含硅铁基体上。灰铸铁的性能取决于石墨片的大小，数量和分布以及基体结构[1-4]。在大多数情况下，工业合金凝固带有树枝晶。通过把这些合金的树枝状结构改变成球状结构，可以提高它们的力学性能。在半固态区剪应力的应用导致树枝晶分裂成小颗粒。连续降低温度和增加压力导致微粒先形成花状结构然后转化为球形结构[5,6]。 灰铸铁半固态成形使用冷却板的方法已在文献[7-9]有所报道，其中得到一个相邻相有清楚区分的改善的结构，这个结构的初始细球状粒子具有高等级的圆球度和相数。然而，以前的文献[7-9]没有任何包括关于石墨片的分布、基体结构和在初始固相分数的宽范围上对抗拉强度影响的讨论。为建立合理 实际的铸铁半固态成形过程，知道固相分数、铸造性、得到铸造性能之间的关系是非常重要的。 本报告的目的是研究通过采用冷却板技术的半固态加工造成灰铸铁微观结构的变化对其抗拉性能的影响。我们对不同的固相分数对结构和抗拉强度的影响进行了研究，以实现这一目标。并期望生产出在最优化条件下适合于工业应用的一个新材料。
2 实验工作 2.1 铸件 本实验中，试样尺寸如图1所示，其尺寸固定为宽25 mm、长155 mm、厚14 mm。砂型使用AFS的石英砂69 GFN、6%的钠基膨润土和1%的谷物制成。成型后将模型封好，在砂型表面喷涂磨砂层，然后在437 K干燥2.5 h。试验所用材料为是灰铸铁棒材。铸铁样品的化学成分如表1所示。试样重约900 g，用电阻炉熔化。炉料在氩气气氛加热到温度为1773 K，然后保温30分钟，让炉料以达到所需的温度。在1773 K时，将熔融炉料从炉中移动到可控浇注系统，这个系统由控制熔体温度的隔离箱和调整浇注速度的快速多变电机组成，如图2所示。在所需的温度，熔融炉料倒在一个倾向于水平面10˚且带有转速为600 r/m连续转动电机的冷却板上，并流入冷却板端部模具型腔。浇筑之前在冷却板表面上放置重量为总重量的0.4%的75FeSi孕育剂。通过插在隔离箱和砂型上的热电偶测量半固态浆料的温度。初生固相分数可使用Scheil方程由以上温度推出。其中奥氏体分布系数k由Goettsch和Dantzig模型确定。
图1 铸造试样设计（以mm为单位）。 表1 铸铁样品的化学成分（质量分数，%） 图2 浇注系统 2.2 显微组织观察和力学性能测定 矩形铸铁样品由条状铸样获得。在距离浇注底部35 mm的横截面进行了微观结构分析，SEM观察和硬度测量。对试样进行打磨和抛光，利用光学观察显微镜对其进行微观结构观察。并运用图像分析软件对试样初生奥氏体粒子的大小，颗粒度以及石墨长度进行了测量和分析。布氏硬度测试载荷750 KG。拉伸试样取自条带试样。拉伸试样按照ASTM，A339标准，长25 mm、直径6.5 mm，采用50 KN拉力试验机。每个条件测试两个拉伸试样。采用配备有能谱射线分析仪（EDS）的日立S-800型扫描电子显微镜对拉伸试样的断口形貌进行了分析。
3.结果及讨论 3.1 显微组织 图3 固相分数对半固态加工的灰铸铁结构的影响 图4 固相分数对平均初生奥氏体颗粒尺寸和初生奥氏体颗粒的圆球度的影响 当温度降到液相线下时，普通亚共晶灰铸铁的凝固是随着奥氏体枝晶从熔体中析出开始的。如图3和4所示，固相分数对半固态加工的灰铸铁结构的影响。很显然，普通灰铸铁有树枝状结构，另一方面，通过增加固相分数，半固态加工的灰铸铁变细更圆。现在和以前的[7-9]调查都很符合这点，初生奥氏体颗粒形状和大小受到因冷却板的使用而由此产生的高熔体冷却速度的影响。高的熔体冷却速度相对于潜热消散速率增加了有效原子核的数量。图4显示，随着增加固相分数，初生奥氏体颗粒平均尺寸［（最大直径+最小直径）/2］减小，这被认为是由于在较高的固相分数下增加凝固速度。
图5 固相分数对半固态加工灰铸铁的石墨大小与分布的影响 图6 平均石墨长度作为固相部分作用的表征 图5和6显示固相分数对半固态加工灰铸铁石墨大小与分布的影响。显然，增加固相分数降低了石墨的大小，并改变其分布。另一方面，对于低的固相分数（FS≤0.12），获得片状石墨（A型石墨）。进一步提高固相分数（从FS0.14至0.18），结果形成细石墨形态的（D型石墨）。这种石墨形态通过为碳提供短的扩散路径来干扰完全珠光体基体，因此，有助于铁素体的形成[1]。 当金属液冷却到液相以下，奥氏体沉淀析出，液体逐步富积碳一直达到共晶成分（4.3%）。一旦这种成分达到，剩余的液体转变成两种固体，在稳定反应的情况下成为石墨加奥氏体。一旦共晶凝固结束，无液态金属残留，固体将发生进一步反应[4]。在共晶转变温度和共析转变温度之间，高碳奥氏体排碳，其扩散形成片状石墨。这给奥氏体吸收所需共析转变的成分的机会。如图7所示，这一转变包含的奥氏体分解成珠光体或珠光体加铁素体。
图7 含不同固相分数铸铁的共晶区的SEM照片 图8 不同初生固相分数灰铸铁的凝固冷却曲线 如图7所示，图7显示了固相分数对半固态加工灰铸铁的共晶结构的影响。这是明确指出，通过增加固相分数，石墨形态由A型的粗片状改变成D型的细薄片状。共晶奥氏体分解为珠光体加铁素体。在固相分数为0.18的试样上生成高铁素体区，此时石墨片主要呈D型。图8显示了在各种固相分数比例下的灰铸铁凝固冷却曲线。结果表明，增加起始固相分数，过冷度增加，且在固体分数为0.20时达到最高值。迄今为止[4,12]的调查是都符合这点，小过冷度普通铸铁生成A型石墨，而D型石墨形成于过冷度高但不足以引起碳化物形成时。更高固相分数造成更高的冷却速度，而导致过冷度的可能增加。最后，我们可以说，冷却板对奥氏体基体和石墨有一个再次细化作用，否则结构将类似于带有树枝状晶体的初生奥氏体和粗石墨的普通铸铁。
3.2 力学性能 3.2.1 拉伸强度 图9 固相分数对半固态成形灰铸铁强度的影响。 如图9所示固相分数对半固态加工灰铸铁的拉伸强度和延伸率的影响。与普通灰铸铁比较由于优良的石墨形成（细石墨A型），对于低固相分数(FS≤0.12)来说，随着固相分数的增加，抗拉强度增加，伸长率也增加。进一步增加固相分数(FS =0.14-0.18)导致石墨形态成为更细的(D)型石墨，因此抗拉强度下降。最后，固相分数增加(FS>0.18)，由于初生固体颗粒团聚区导致抗拉强度增加。这些初生固体颗粒团聚区割裂了如图10所示的共晶石墨网络。
图10 SEM照片显示固相分数0.23(箭头表示的粒子群的位置)固体颗粒集聚：(a)微观结构粒子群; (b)所示(a)图中B点宽共晶区; (c)所示(a)中A点狭窄的的共晶区
以往的研究也定性的描述了石墨形态和基体的特征对力学性能的影响，其中的小石墨片和最大的奥氏体基体含量都被认为以提高了铸铁的强度。铸铁中裂纹的萌生和增殖受基体塑性变形能量吸收程度的影响。在带有细石墨和比普通灰铸铁更宽的石墨间基体链接的半固态加工灰铸铁(FS≤0.12)的情况下，塑性基体断裂的能量吸收得到增加。另一方面，对于固相分数介于0.14和0.18之间的半固态加工灰铸铁，它被认为是在带有介于石墨段和共晶铁素体之间很短的桥梁的细小石墨对在断裂处塑性基体的能量吸收量生产了缩减。 对这项研究中，采用冷却板技术的半固态加工给基体晶粒细化和石墨的析出优势，通过快速凝固和流动相关的树枝晶碎片之间的结合，树枝晶碎片变成了球状结构，从而提高铸铁产品的抗拉强度。石墨类型和基体结构可以通过采用半固态加工艺加以控制。尽管D型石墨片可以在固相分数0.12和0.18之间生产，却产生一个低抗拉强度，报告D型小片产生通过细化机械加工得到最大限度地减少表面点蚀的表面光洁度。由于这种良好的表面处理，灰铸铁玻璃模具被认为是其最重要的应用之一。
3.2.2 断面 图11 拉伸试验样品断口和EDS模式：(a)普通铸铁的断口;(b)半固态铸造(FS =0.05)的断口;(c)半固态铸造(FS=0.18)断口; (d和g) (a)所示的点A和B的 (EDS)谱； (e和h) (b)所示点A和B的(EDS)谱；(f和i) (c)中所示点A和B的(EDS)谱
图11-(i)显示，普通铸铁和两种固相分数半固态成形铸铁的断面的SEM照片和EDS谱。图11 (a)显示带有解理和准解理面的普通灰铸铁脆性断面特点。图11 (b)所示固相分数为0.05的半固态铸造的断口形貌。半固态加工生产细晶粒结构，根据当地伸展产生相对较长，沿着尖锐的峰形断裂面。图11 (c)所示固相分数为0.18的半固态铸造断口形貌。通过观察断口注意到，石墨相中相互关联的条件造成断裂内明显偏低基体贡献。图11 (D)-(i)显示从共晶石墨和基体照的一个典型谱，表明在共晶石墨一个明确的碳的峰值和在基体一个明确的铁峰值。断裂面的观察证实，总断裂强度主要取决于基体的影响程度，而基体的影响程度是根据固相分数值而改变。对于固相分数0.05的断口形态，细晶粒结构和宽石墨分部之间的桥梁，提高塑性基体在断裂处的能量吸收，并与普通的和固相分数0.18的半固体铸造相比其导致强度增加。在断裂面之间的河流花样和纤维流可以观察，表明在半固态加工灰铸铁中混合韧脆性断裂花样盛行。
3.2.3 硬度
图12 固相分数对贝氏硬度的影响 图13 贝氏硬度普通和半固态铸造 如图12硬度值作为固相分数的功能。增加固相分数硬度通常会增加。固体分数增加高于0.12灰铸铁会由于铁素体的形成与D型石墨形态而硬度开始降低。然而，与普通铸铁硬度比较这种高硬度值得益于一个带有球状基体相和细石墨片特征的微观组织。如图13所示硬度值与从中央到试样截面边缘的距离有关。与半固态铸造相比，普通铸造的情况下显示了一个比较大的变化。对于通过增加固相分数的半固态加工铁灰铸铁样品在截面不同位置