电液控制阀的外文翻译
电液控制阀
电液阀是机械运动的组成部分，其运动直接受电子电路的影响。对于液油压系统设计者来说，它已成为了一个流行的部分。电子阀门的主要类型是开关，比例，伺服阀和数字阀。根据1995年美国科学作家沙利文估计，电子IC与常规液压阀需求预计年均增长速度在5%左右。销售比例和伺服阀据估计会在3个主要应用领域增加，这3个领域分别是移动机械、机械工业、航天设备.一般而言，有液压阀的综合电子电路会增加机器的准确性和速度。运用电子系统也会有一些缺点。在一些应用中，由于热，部分效率会丧失。Vickers公司已经设计出了能代表未来电子系统的。它是专门的机器，其主要组成部分是比例阀、缸和数码控制。
1993在美国获专利的机械工程师jun是液油压系统设计者。他们工作时是否使用机器人或自行移动机器和对于它们已经开始使用电脑和廉价的电子元件，这会改善液压系统性能还可以省钱。
电子阀是机械的组成部分，其运动直接受电子线路影响。它已成为系统设计者设计的一个流行的部分了。液压控制是反过来受电子部分控制的。象扭矩马达或螺线管，通常是用电流通过一个有距离的比例阀来使它的线圈阀运动的电子阀的主要类型是开关、比例阀、伺服阀和数字阀. 该装置是固定在流体之间来提供动力和驱动源泉的，如扶轮摩托以及控制流体的压力、方向和曲率的。它能使机器控制驱动器组成部分的加速、速度、位置和力量的。
在 Bethlehem, Pa.Rexroth公司的产品开发部门的经理 Paul Stavrou说：“电子控制液压系统在20世纪40年代已经有了，但是直到80年代初期具有微型化,降低成本和高可靠性优点的它才蓬勃运用于工业。
主要生产电子阀的公司包括Rexroth，Vickers公司，总部设在Troy, Mich；Parker Hannifin Corp. of Cleveland, Ohio; and Eaton Corp. of Eden Prairie等等这些地方。每阀有截然不同的作用，取决于它的类型。
最简单的就是开关阀。它的开关转换是通过前后来回转换线圈来实现的。在"on"的位置上，线圈于阀位置的排成一条直线通道，它允许一定量流体流动通过装置。在“off”位置上，线圈隔开连通渠道。通过调节电子控制螺线管流通速度可以使同一个阀的开关有不同的速率。这类型的控制有时也叫做“bangbang控制”，因为高强度的阀会过度震荡产生噪音。
一般而言，比例阀会比较精确的按照流体的速度和压力来控制并对电子输入信号迅速做出反应。Stavrou说道：“电子控制已经给予比例阀精确度和信号反应时间，所以它适合应用于大多数工业。”
比例阀运行时,线圈运动是靠一个有距离的直接成正比的有电螺线管来实现的。比如说在Rexroth公司生产的一个比例阀中，电动放大器接收到的信号为9伏特,它转换成当前高达1.5安培的电流.电流到达了一个有可以往返移动活塞的电动螺线管，被发送到螺线形电导管的定量电流控制着活塞移动线圈阀移动一段距离。
随着时间的推移，流动量也改变。阀有变化地控制速度和驱动的力量。简单的说，一个比例阀可以改变流体的流动方向，也可以在一个驱动构件中控制输出部件的方向。
比例阀通常被用在工作时无感应反馈的中开放性系统。不过,他们有时也被纳入封闭性的系统中。封闭性系统就是在其中一个传感器,通常是有差别的可变线性变压器传送可以告知控制者在每一个反复运动中螺线管活塞的位置的信号的。传感器也可以发出衡量驱动构件输出的信号。
现在包含比例阀的封闭性系统，曾经是伺服阀的领域。伺服阀通常比比例阀制作的更精确，通常有两三个阶段。
通常第一阶段，在试验电路中螺线管或扭矩马达控制流体流动。（一些扭矩马达在不是试验电路中有足够的力量去直接控制阀。）第二阶段中，试验电路控制能调节流体流动到驱动构件的活塞阀的运动。
当使用扭矩发动机时, 电流被输送到其旋管使转子转动。转子与一个可在孔中来回转动的挡板连接。在实验电路中，这些孔是到达两个相分离渠道的通道。
另外，通向线圈相反端的渠道控制阀的第二阶段。在接到电流时,扭矩马达会调整flapper板的位置。不同压力情况下，流体会流向线圈相反的方向。然后线圈
会移动一段距离，这个距离与不同的压力和输送到发动机的电流有关。在线圈位置上的反馈通常是由一个线性的变数差别的变压器提供的。
比例阀和伺服阀通常是由放大器和滑向系统控制架的控制卡来控制的。当一些还在被传统的软件和硬件控制时，最先进的伺服阀已经与规划和电脑数值控制相联系了。安装阀的时间应该保持到最小值，而且机器空间是紧的，控制卡应直接固定到阀的位置。
应用及滥用
伺服阀比比例阀性能跟高, 但他们是更加昂贵的。根据美国Frost &
Sullivan公司的市场调查，与它的复杂性有关，每个伺服阀的价格大约在$1000
到 $2000之间。电子控制器价格可能会增加超过$500。然而，比例阀平均会是那
些花费的一半。
据Frost & Sullivan公司.1995年估计，美国对电子和常规水力阀的需求预计以
每年5%的年率增长。比例阀和伺服阀的销售量预计会在三个主要应用领域增加:
移动机械、工业机械, 和航空航天设备。
例如,在移动机械市场上,电动液压阀必须有多功能而且坚固。他们必须适合机器, 包括垃圾车, 铲车, 和挖掘机。阀经常在户外使用，这样会导致振动。
电动液压的阀门的一个好处是, 他们在操作重设备时能增加安全性。例如，大多数起重机,禁止了一些区域。这些区域是机器不能设法运载重的装载或它也许下落的区域。
然而在过去五年里, 为了使操作人员更好的操作机器以及限定危险的区域，起重机制造商开始对他们的常规液压系统增加传感器。根据Vickers公司的先进技术经理弗雷德菲利普所估计，如果起重机制作商最终决定使用微处理器控制, 安全系统将是更加有效的。他说："微处理器使设计一个系统成为可能。这个系统就是能够自动使起重机在被禁止的区域外部的系统。"
Vickers 公司把电动液压阀投入到新用途的使用中。例如在Burbank和Calif.的娱乐业, 他们把那个公司的电液比例阀运用在行动模拟器上。这个机器包括震动模仿运动譬如加速度、减速, 和自转。
电动液压阀也使用在转台式行动控制上。Eaton 流体分裂制作了一个电子速度控制系统来提高使用在建筑业搅拌混凝土的运输搅拌器的耐久性。由于电液阀为混合鼓自动速度控制提供独立发动机速度，因此机器的使用寿命被提高了。
引擎驱动鼓通过一个水力泵、马达, 和齿轮还原剂。当混凝土搅拌时，鼓每分钟转动在1 和17 转之间。在泵内，二个伺服阀控制流体流入一台流体伺服机。二条螺线管致力不同的流程方向，使每个阀都接收到从计算机控制器发出的信号并允许液压机液体转动的流动以使混合鼓以渴望的速度转动。计算机接收来自泵输出轴的一个霍尔效应传感器的鼓速度的连续的测量。
没有电子控制, 在机器内当速度增加和减少时，搅拌器也跟着加速和减速。发动机的转动速度的比例会影响搅拌器的耐久性, 主要取决于在它的使用期间混凝土鼓转动多少次。鼓的转动也会影响引擎消耗的燃料量。
使用电子速度控制系统, 机器操作员能使混合鼓的速度降低到1 转每分钟, 有效地打破搅拌器的和那引擎之间速度的连接。因而，混合鼓在工作的地方会更多的减少转动次数。在这个过程中节省下来的机器能量可以更好的利用到它工作的地方。
Eaton 声称电子系统会使搅拌器的使用寿命增加一年。而且这个公司的研究表明由于引擎产生较少马力，对于混凝土的每一次装载，电子系统会减少引擎0.8 加仑的燃料消耗量。
在众多优点中, 速度控制系统会自动地控制混凝土的混合速度。计算机系统也会存储以往每批混凝土的资料, 包括在混合期间鼓的转动数和自鼓转动开始消耗的时间多少。这些数据对于评估已完成的混凝土结构的完整性的房屋检查员是有价值。
是否要使用电液
通常,电子线路和流体阀的综合会增加机器的运转的速度和精确度。譬如执行一项特殊任务,在挖掘机里转动桶。电液会比传统无电的阀控制使用较少能量和有更好的精确度。传统方法包括直接给螺线管通电而使机械和自动控制连接，从而手工阀。
在许多应用中，机电系统可以代替电液系统。例如, ac 马达会给予退弹管道系统的机器工具轴以能量。在许多情况下，机电系统与电动液压相比较，它们不会漏油, 通常更加安静,较不昂贵，对时尚模式和数字控制的反应更加直接。
而且使用电动液压的系统也会有一些缺点。例如, 在某些应用中,由于热构件的效率会流失。另外, 对电子使用会使设计,应用和维护的液压机构的复杂性增加。例如,一位电液系统设计师必须使电子元件在苛刻的操作条件譬如到处温度和过份振动中，受到保护。
电动液压的系统经常用于控制移动机械的行动。这里, 液压构件的优点就是依照设计者的意愿，它们能用机器相对小的空间来移动高而且重的装载。
设计怎样去控制机器的行动经常取决于系统设计师是否了解应用和维护各个系统的细微差异。因为用户可能更了解传统液压系统的操作, 他们害怕无法改正电子问题，这是电液制造商面对的一个障碍。
所以，电液构件制作商决定设计容易使用和维护的产品。Eaton 公司的运输搅拌器有一个诊断的特点，它允许卡车司机精确定位和确定电子失误的原因。当有问题时, 代码会出现在小室的一个诊断盘区，司机可以跟踪代码查明故障以及根据提示作出处理。
对电液系统的采纳是用户关于构件的性能怎样与一种特殊应用匹配，这是很重要的。根据电液系统制作商所说, 随着时间的推移用户会发现有流体构件的连接电子的优点。但是, 一些用户对于由控制传统方法的转换持有怀疑态度。Vickers公司机械系统经理Paul Smith说：“我们的顾客应该肯定对液压系统增加复杂性的价值。他们会认识到产品会回报他们投资在它上面的额外金钱。回报来自更多地方,例如，减少在设施和维修方面的费用。" Smith说：“发展趋向是首先为用户实施一个开放的环形系统。然后, 当他们与它相适应时,再使他们转向更加复杂但更加准确的闭环系统。”
发展中的改善
Vickers公司的先进技术小组正致力于对电液系统的一系列改善。例如, 工程师正对用于特定产品和多用途产品的控制器进行改善。另外, 他们正设法提高能量利用率，减少噪声和挖掘电液系统的潜力。
进一步,这个公司设计了他们认为能代表未来的电液系统:一台专业的发动机。他的主要构件是比例阀、圆筒和一位数字式控制器。除了减少液压系统的构件数量以外, 这种专业的发动机还有其它的优点。例如,在设计一个液压系统时, 为了符
合应用要求，许多工作会进行优化。在这种专业的发动机里，为了一系列应用，获取到的它的工作情况会被编程到控制器里。因此, 系统设计师就节省了花费在调整控制系统的时间。没有一台专门的发动机，系统设计师设置的在电子控制器里的决定它效率工作情况的获取将会是错误的。
发动机里开发软件的应用也使记录运转控制的工作情况变得容易了。最具代表性的就是程序员用一台个人计算机就可以连接发动机的控制器。软件和它的帮助菜单随后被一步步用到审阅编程处理中, 省去了在操作指南中的查找。
Vickers公司的Phillips说：“系统设计师的一个目标就是选择能在运用中
带来良好结果的构件。”设计师必须记住逻辑上什么零件在一起运作得最好。同时, 他们设法使零件数量减到最少而仍然达到必需的效果。使系统变的更灵活，要想达到那样的目的才更容易。
Electrohydraulic valves take control
Copyright American Society of Mechanical Engineers Jun 1993 The electrohydraulic valve, a mechanical component whose movements are directly influenced by electronic circuits, has become a popular part for system designers of hydraulic fluid systems. The main types of electrohydraulic valves are on-off, proportional, servo, and digital valves. The demand for electronic and conventional hydraulic valves is expected to grow at an annual rate of 5% in the US through 1995, according to Frost & Sullivan. Sales of proportional and servo valves are expected to increase in the 3 primary areas of application: mobile machinery, industrial machinery, and aerospace equipment. Generally, the integration of electronic circuits with hydraulic valves increases the precision and speed of a machine's motion. There are also a few drawbacks associated with using electrohydraulic systems. In some applications, component efficiency is lost because of heat. Vickers Inc. has designed what it feels represents the electrohydraulic system of the future: an expert actuator whose primary components are a proportional valve, a cylinder, and a digital controller.
Designers of hydraulic fluid systems, whether they are working with robots or mobile earth movers, are beginning to use compact and inexpensive electronic components to both improve the performance of the hydraulic systems and save money.
The electrohydraulic valve, a mechanical component whose movements are directly influenced by electronic circuits, has become a popular part for system designers. This regulator of fluids is in turn regulated by an electric component, such as a solenoid or torque motor, that
typically moves the spool of the valve through a distance proportional to an electric current.
The main types of electrohydraulic valves are on-off, proportional, servo, and digital valves. The devices are mounted between the fluid supply source and a driven actuator, such as a rotary motor, and control a fluid's pressure, direction, and Bow rate. They enable the actuator to control the acceleration, velocity, position, and force of the driven machine component.
"Electronic controls for hydraulic systems have been around since
the 1940s, but it was not until the early '80s, with their miniaturization, lower costs, and improved reliability that they began to flourish in industry," said Paul Stavrou, manager of systems and product development at Rexroth Corp's. servo and proportional controls group in Bethlehem, Pa.
The leading producers of electrohydraulic valves include Rexroth; Vickers Inc., based in Troy, Mich.; Parker Hannifin Corp. of Cleveland, Ohio; and Eaton Corp. of Eden Prairie, Minn. Each valve has a distinctly different level of performance depending on its type (see table on page 56 ). (Table omitted)
The simplest is the on-off valve, which turns the valve on and off by shuttling a spool back and forth. In the "on" position, channels in a spool align with ports in the valve housing and allow the flow of a defined volume of fluid through the device. In the "off" position, the spool blocks off the port. The same valve may be turned on and off at varying rates b an electronically controlled solenoid to modulate the rate of flow. This style of regulation is sometimes called bang-bang
control because at high power the valves often vibrate excessively and are noisy.
The proportional valve is generally more precise in terms of the
rate and pressure of flow that it controls, and faster in its response to electronic input signals. "Electronic controls have given
proportional valves accuracy and signal-response times that are adequate in most industrial applications," Stavrou said.
When a proportional valve is operating, its spool moves through a distance directly proportional to the current received by a solenoid. In one of Rexroth's proportional valves, for example, an electric amplifier receives a signal of up to 9 volts, which it converts into a current of up to 1.5 amps. The current reaches an electric solenoid, which has a plunger that moves back and forth. The plunger moves the valve spool through a distance defined by the measure of current sent to the solenoid.
By changing the volume of flow over time, the valve variably
controls the speed and force of a driven unit. Similarly, a proportional valve that changes the direction of flow also controls the direction of output components on a driven unit.
Proportional valves are often used in an open-loop system that works without sensor feedback. However, they are sometimes integrated into closed-loop systems in which a sensor, usually a linear variable differential transformer, sends signals that tell the controller where the solenoid plunger is during each stroke. The sensor can also send signals that measure the output of the driven unit.
Closed-loop systems, which now incorporate proportional valves, were once the domain of servo valves. The servo devices are machined more precisely than proportional valves and usually have two or three stages.
Typically, in the first-stage a solenoid or torque motor controls
the flow of fluid in a pilot circuit. (Some torque motors are powerful enough to directly control valves without a pilot circuit.) In the second stage, the pilot circuit controls the movement of the valve spool, which itself regulates fluid flowing to the driven unit.
When a torque motor is used, an electrical current is sent to its coils to move an armature. The armature is connected to a flapper plate that moves back and forth between orifices. These orifices are entry ports to two separate channels within the pilot circuit.
Separately, the channels run to the opposite ends of a spool that controls the second stage of the valve. Upon receiving the electric current, the torque motor adjusts the position of the flapper plate. A difference in pressure emerges between the fluid flowing to opposite ends of the spool. Then the spool moves through a distance that is
related to the pressure difference and electric current sent to the motor. Feedback on the position of the spool is often provided by a
linear variable differential transformer.
Proportional and servo valves are usually controlled from amplifier and control cards that slide into system control racks. The most sophisticated servo valves are often linked to programmable and computer numerical controllers, while some are controlled by custom software and hardware. In applications where time spent installing the valve needs to be kept to a minimum and machine space is tight, control cards are mounted directly into the valve's housing.
USE AND ABUSE
Servo valves hare higher performance than proportional valves, but they are more expensive. The average servo valve costs between $1000 and $2000, depending on its complexity according to the research firm Frost & Sullivan Market Intelligence in New York. Electronic controllers can add more than $500 to the price. The average proportional valve, however, can cost half that much.
The demand for electronic and conventional hydraulic valves is expected to grow at an annual rate of 5 percent in the United States through 1995, according to Frost & Sullivan. Sales of proportional and servo valves are expected to increase in the three primary areas of application: mobile machinery, industrial machinery, and aerospace equipment.
In the mobile machinery market, for example, electrohydraulic valves must be versatile and rugged. They have to fit in a range of machines, including garbage trucks, forklifts, and excavators. The valves are
often used outdoors and in conditions that induce vibrations.
One benefit of electrohydraulic valves is that they can increase safety in operating heavy equipment. Most large cranes, for example, have forbidden zones into which the machine must not try to carry heavy loads or it may fall over.
Within the past five years, however, crane makers have begun adding sensors to their conventional hydraulic systems to keep the operator better informed of the outline and limits of the danger zone. If crane makers eventually decide to use microprocessor controls, the safety system will be even more effective, according to Fred Phillips, manager
of advanced technology at Vickers. "A microprocessor makes it possible to design a system that automatically keeps the crane outside the forbidden zone," he said.
Vickers' electrohydraulic valves are being put to novel uses. For example, Iwerks Entertainment in Burbank, Calif., uses the company's electrohydraulic proportional valves in a motion simulator used in the entertainment industry. This machine consists of a seat that shakes to simulate movements such as acceleration, deceleration, and rotation.
Electrohydraulic valves are also used in the control of rotary motion. The hydraulics division of Eaton makes an electronic speed-control system that improves the durability of transit mixers used in the construction industry to mix concrete. The lifetime of the machine is improved because electrohydraulic valves provide for the automatic control of speed of the mixing drum, independent of engine speed.
The engine drives the drum through a hydraulic pump, motor, and gear reducer. The drum rotates at between 1 and 17 rpm when concrete is mixing. Two servo valves control the flow of fluid into a hydraulic servo in the pump. Two solenoids dedicated to different flow directions and mounted to each valve take signals from a computer controller and allow the hydraulic fluid to flow at a rate and pressure that rotates the mixing drum at the desired speed. The computer receives continuous measurements of the drum's speed from a Hall-effect sensor mounted at the output shaft of the pump.
Without electronic controls, the mixer accelerates and decelerates as speed increases and decreases in the engine. Rotating in proportion to engine speed influences the mixer's durability, a characteristic that largely depends on how many times the concrete drum turns during a
lifetime. The drum's rotation also influences the amount of fuel the engine consumes.
With the electronic speed-control system, the machine operator can reduce the speed of the mixing drum to 1 rpm, effectively breaking the link between the speed of the mixing machine and that of the engine. The mixing drum, consequently, turns far fewer times on its way to a work site. Mechanical energy saved on the journey is put to better use at the work site.
Eaton claims the electronic system adds a year to the life of a transit mixer. Further, a study conducted by the company shows that the electronic system reduces the engine's fuel consumption by 0.8 gallon
for each load of concrete due to the engine generating less horsepower.
Among other benefits, the speed-control system automatically
controls the speed at which concrete is mixed. The system's computer also stores historical information on each batch of concrete, including the number of drum turns during mixing and the length of time that has elapsed since the procedure took place. These data are valuable to building inspectors, who evaluate the integrity of the finished concrete structure.
USING ELECTROHYDRAULICS OR NOT
Generally, the integration of electronic circuits with hydraulic valves increases the precision and speed of a machine's motion. A particular task, such as rotating the bucket on an excavator, can be performed using less energy and with greater precision than by
traditional nonelectronic methods of valve control. The traditional
methods include manual control of a valve through mechanical links and automatic control by directly energizing a solenoid.
Electromechanical systems can take the place of electrohydraulic systems in many applications, however. For example, ac motors often power machine-tool axes with ball-screw feed systems. Electromechanical systems in many cases are competitive with their electrohydraulic counterparts; they cannot leak oil, are often quieter, can be less expensive, and respond in a more linear fashion to analog and digital control.
There are also a few drawbacks associated with using
electrohydraulic systems. For example, in certain applications, component efficiency is lost because of heat. Additionally, the use of electronics may increase the complexity of designing, applying, and maintaining hydraulic systems. An electrohydraulic system designer, for example, may have to shield electronic components from harsh operating conditions, such as high and low temperatures and excessive vibration.
Electrohydraulic systems are often used to control the motion of mobile machinery. Here, the defining advantage of hydraulic systems, their ability to move high loads using a relatively small volume of the machine's space, weighs heavily in the designer's decision.
The decision of how to control machine motion often depends on whether the system designer is familiar with the nuances of applying and maintaining each system. Since the user is likely to be more familiar with the operation of traditional hydraulic systems, the fear of being unable to correct electronic problems is one obstacle faced by makers of electrohydraulic systems.
As a result, makers of electrohydraulic components are designing products that are easy to use and maintain. Eaton's transit mixer has a diagnostic feature that allows a truck driver to pinpoint the location and reason for an electronic failure. When there is a problem, a code appears on a diagnostic panel in the cab and the driver can track the code to a troubleshooting procedure in a manual.
Just as important to the acceptance of electrohydraulic systems is the user's knowledge of how the performance of a component matches a particular application. According to makers of electrohydraulic systems, over time users become more aware of the benefits of linking electronics with hydraulic components. Still, some users are skeptical of switching from traditional methods of control. "Our customers have to determine the value of adding sophistication to the hydraulic system," said Paul Smith, a manager of systems engineering at Vickers. "They have to see that the product will pay back the extra money they have invested in it. Payback may come, for example, from more parts per hour or reductions in installation and maintenance costs." The trend, Smith said, is for users to first implement an open-loop system. Then, when they become comfortable with it, they move to the more complex but more accurate closed-loop system.
DEVELOPING IMPROVEMENTS
The advanced technology group at Vickers is working on a number of improvements to electrohydraulic systems. For example, engineers are developing controllers that are dedicated to specific products and applications. Additionally, they are trying to improve energy efficiency and reduce noise and the potential for leakage in electrohydraulic systems.
世界贸易和国际贸易【外文翻译】
外文翻译 原文 World Trade and International Trade Material Source:https://www.360docs.net/doc/9311041354.html, Author: Ted Alax In today’s complex economic world, neither individuals nor nations are self-sufficient. Nations have utilized different economic resources; people have developed different skills. This is the foundation of world trade and economic activity. As a result of this trade and activity, international finance and banking have evolved. For example, the United States is a major consumer of coffee, yet it does not have the climate to grow any or its own. Consequently, the United States must import coffee from countries (such as Brazil, Colombia and Guatemala) that grow coffee efficiently. On the other hand, the United States has large industrial plants capable of producing a variety of goods, such as chemicals and airplanes, which can be sold to nations that need them. If nations traded item for item, such as one automobile for 10,000 bags of coffee, foreign trade would be extremely cumbersome and restrictive. So instead of batter, which is trade of goods without an exchange of money, the United State receives money in payment for what it sells. It pays for Brazilian coffee with dollars, which Brazil can then use to buy wool from Australia, which in turn can buy textiles Great Britain, which can then buy tobacco from the United State. Foreign trade, the exchange of goods between nations, takes place for many reasons. The first, as mentioned above is that no nation has all of the commodities that it needs. Raw materials are scattered around the world. Large deposits of copper are mined in Peru and Zaire, diamonds are mined in South Africa and petroleum is recovered in the Middle East. Countries that do not have these resources within their own boundaries must buy from countries that export them. Foreign trade also occurs because a country often does not have enough of a particular item to meet its needs. Although the United States is a major producer of sugar, it consumes more than it can produce internally and thus must import sugar.
农产品物流外文翻译
毕业论文外文翻译（一） 论文题目：国外发展农产品物流的成功经验及其对浙江的启示 外文题目：Logistics &the National Economy 出处：International Journal of Physical Distribution & LogisticsManagement 作者：MCB UP Ltd 原文： Logistics &the National Economy Introduce Logistics has always been a central and essential feature of all economic activity and yet paradoxically it is only in recent years that it has come to receive serious attention from either the business or academic world. One very obvious reason for this neglect is that, whilst the functions that comprise the logistics task are individually recognised, the concept of logistics as an integrative activity in business has only really developed within the last 20 years. What is logistics? It can be variously defined, but expressed at its simplest it is: The process of strategically managing the movement and storage of materials, parts, and finished inventory from suppliers, through the firm on to customers. Logistics is thus concerned with the management of the physical flow which begins with sources of supply and ends at the point of consumption. It is therefore clearly much wider in its reach than simply a concern with the movement of finished goods—a commonly held view of physical distribution. In the logistics scheme of things we are just as much concerned with plant and depot location, inventory levels, materials management and information systems as we are with transport. One of the features of the logistics concept which is its greatest attraction whilst simultaneously being the greatest drawback to its widespread adoption in industry so far is that it places the emphasis on integrating activities that traditionally have been located in different functions of the business. Thus in many
进出口贸易专业术语中英文对照
银行英语： 出口信贷 export credit 出口津贴 export subsidy 商品倾销 dumping 外汇倾销 exchange dumping 优惠关税 special preferences 保税仓库 bonded warehouse 贸易顺差 favorable balance of trade 贸易逆差 unfavorable balance of trade 进口配额制 import quotas 自由贸易区 free trade zone 对外贸易值 value of foreign trade 国际贸易值 value of international trade 普遍优惠制 generalized system of preferences-GSP 最惠国待遇 most-favored nation treatment-MFNT -------------------价格条件 ---------------------- 价格术语trade term (price term) 运费freight 单价 price 码头费wharfage 总值 total value 卸货费landing charges 金额 amount 关税customs duty 净价 net price 印花税stamp duty 含佣价price including commission 港口税portdues 回佣return commission 装运港portof shipment 折扣discount,allowance 卸货港port of discharge 批发价 wholesale price 目的港portof destination 零售价 retail price 进口许口证inportlicence 现货价格spot price 出口许口证exportlicence 期货价格forward price 现行价格（时价）current price prevailingprice 国际市场价格 world (International)Marketprice 离岸价（船上交货价）FOB-free on board 成本加运费价（离岸加运费价） C&F-cost and freight 到岸价（成本加运费、保险费价） CIF-cost,insurance and freight --------------------交货条件 ---------------------- 交货delivery 轮船steamship(缩写S.S) 装运、装船shipment 租船charter (the chartered shep) 交货时间 time of delivery
外文翻译--绿色壁垒对我国农产品贸易的影响及对策
绿色壁垒对我国农产品贸易的影响及对策 当前，在国际贸易中绿色贸易壁垒已成为最重要的贸易的贸易壁垒之一，农业作为一种弱势产业更容易受到影响。绿色贸易壁垒是我国农产品出口所面临的严峻挑战，也是我国农产品出口最大的障碍。由于农产品贸易在我国对外贸易中占有重要地位，因此如何突破绿色贸易壁垒对我国农产品出口限制，对推动我国农产品发展具有重要的现实意义。 本文首先从绿色贸易壁垒的相关理论出发，对绿色贸易壁垒的定义、产生的根本原因和表现的形式特点进行了综述，研究了国外绿色贸易壁垒对我国农产品出口的影响状况；同时本文还指出我国农产品出口遭遇绿色贸易壁垒的原因，在此基础上运用国际贸易知识对发达国家绿色贸易壁垒对我国的影响分析结合，政府、企业、行业对我国农产品跨越绿色贸易壁垒提出相关的对策和建议。 随着生活水平的提高, 人们越来越重视自身的生活质量问题, 近年来兴起的绿色消费概念正是其中一种现象。而绿色壁垒则是国际社会对环境与贸易关注的结果, 各个国家越来越多地在对外贸易中实施这种保护手段。随着国际市场绿色需求的不断增强, 以及环境保护的共识, 绿色贸易保护迅速兴起, 以环境保护为名的绿色壁垒成为国际经济贸易中重要的非关税保护措施之一。然而, 由于发展中国家与发达国家经济发展程度的不同, 导致各国在对待经济发展与环境保护问题上侧重点的不同, 发达国家在环境保护意识、政策、法规及技术等方面的领先, 而且, 目前各国的绿色贸易壁垒是根据各国自身的情况来设置的,还没有形成世界统一标准的制度, 各国绿色壁垒的限制程度难以预测。这就使目前的绿色壁垒有可能被发达国家利用为限制发展中国家产品进口的重要手段。绿色壁垒不仅对产品的品质提出很高的要求, 而且涉及到产品的产前、产中、产后各个阶段, 给发展中国家的对外贸易与经济发展带来了很严重的影响。 绿色贸易壁垒，是指在国际贸易领域，进口国以保护生态环境、自然资源、维护人类和动植物生命健康和安全为由而制定的一系列限制或禁止进口的贸易措施。由于发达国家所采取的这些措施复杂而严格，对发展中国家产品的出口构成绿色贸易壁垒。
出口货物报关单英文翻译
JG02 Unified Serial No. from Data Centre: Customs Export Declaration Form of the People’s Republic of China
Customs Declaration Form 报关单 An exporter has to apply to the customs for declaration of the commodity before the shipment. The customs officer will sign on the customs declaration form and release the goods if the goods are up to the requirement. 出口方必须在装运前对出口货物进行报关，如果货物符合要求，海关官员就签署报关单对货物进行放行。 The person who asks for declaration is required to be qualified, that is to say, he/she should have the certificate of customs declaration. The examination is held by the General Administration of Customs of 申请报关的人要求具备资质，就是说他或她应有报关证。考试由中华人民共和国海关部署举行。 The customs declaration form is in different colors, for example: the white one is made out for general trade and the pink one is used for processing trade. The contents of these documents are similar. We take the specification of an export customs declaration form for general trade as an example to show the method of making out the document. 报关单有不同颜色，如白色报关单按一般贸易缮制，粉红色报关单用于加工贸易。这些单据的内容相似。我们以一般贸易的出口货物报关单的内容为例介绍该单据的缮制方法。 The Main Contents and Notes of Customs Declaration Form： 报关单的主要内容及注释： 1. 预录入编号：No. of Pre-record It is given by the customs while the exporter is applying to customs. It is given by computers automatically. 出口方申请报关时由海关给的编号，是由计算机自动编制的。 2. 海关编号：No. of Customs It is given by the computer system automatically or given by the custom officer. 由计算机系统自动编制或由海关人员给出。 3. 出口口岸：Port of Export It refers to the name and code of the customs at final port of export. 指最后口岸的海关名称及代码。 说明：若出口货物在设有海关的发运地办理报关手续，出口口岸仍应填写出境口岸的名称。如在深圳办理报关手续，陆路运输至上海出境的货物，其出口口岸为上海。同时加注关区代码。 4. 备案号：record number for checking It refers the number of “Register Manual” or the number of “Certificate of Paid or Free Tax” 指《登记手册》编号或《征免税证明》编号。 5. 出口日期：Date of Export It refers to the date of shipment. It is the applied date of departure of the vessel. 指发运日期，也就是船申报出境的日期。 6. 申报日期：Date of Application It is the date that the exporter applies for declaration. 指出口方向海关申报出境的日期。 7. 经营单位：Executive company Fill in the company’s name who signs and executes the S/C in Chinese, (generally refers to the exporter), and the customs code of the company. 用中文填写签订和执行合同的公司(一般指出口人)名称及经营单位代码。 说明：如果总公司签订合同，由分公司执行，则填分公司名称。出口企业间相互代理，以代理方为经营单位。注意填写全称，注明经营单位代号，该代号是出口企业办理海关注册登记时，海关设置的编码，共10位数字。 8. 运输方式：Mode of Transportation It refers to the final departure mode of transportation , such as sea, road, railway and air, etc. 指货物出境的最后运输方式，如江海、公路、铁路及航空等。 9. 运输工具名称Name of Transportation Tool It refers to the name of departure tool of transportation (for example, sea for vessel and number of voyage, railway for the number of train and air for the number of flight). 指货物出境的运输工具名称(如江海填船名及航次，铁路填车次，航空填航班号)。
关于农产品出口竞争力研究的文献综述[文献综述]
题目：关于农产品出口竞争力研究的文献综述 众所周知，农产品出口对增加农民收入、优化农业结构和加快农业发展均有积极的意义。我国农产品出口额已经连续六年保持上升趋势，但我国的农产品出口在国家贸易结构和世界贸易结构中仍然处于弱势地位，最根本的原因在于我国农产品在国际市场上缺乏强有力的竞争力。我国农产品出口竞争力不强的原因何在，如何提高我国农产品的国际竞争力呢？ 加入WTO后，我国农产品在国际市场上的竞争力更加剧烈，因此如何提高农产品的出口竞争力将是个非常关键的问题。本文将对国内近年来有关于农产品出口竞争力研究成果进行回顾和梳理。文中对农产品出口竞争力的概念，影响因素从国内和国外两个方面进行梳理以及提高农产品出口竞争力的措施进行简单评价 一、有关竞争力的概念 一国外学者认为： 1．竞争力的内涵。 出口竞争力，就是出口产品在国外市场的国际竞争力。古典经济学认为，国际竞争力的强弱取决于一个国家或地域或地区生产要素：劳动力、资金与自然禀赋等方面具有的相对优势，从亚当·斯密创立比较优势论到大卫·李嘉图相对优势论，还有赫克歇尔一俄林自然禀赋理论都沿袭这一看法；经济历史学家强调经济体制在国际竞争中的重要作用，他们认为有利的制度形式是推动国家或地域经济发展的动力，从而也必然促进其国际竞争力的提高。 2．竞争力的理论基础。 长期以来，古典经济学家李嘉图的比较优势论是西方国际贸易理论的“基石”。李嘉图认为，国际贸易的基础并不限于生产技术上的绝对差异，只要各国之间存在着生产技术上的相对差异，就会出现生产成本和产品价格的相对差别，从而使各国在不同的产品上具有比较优势，是国际分工和国际贸易成为可能。他以各国劳动生产率的差异为基础进行分析，认为每个国家或地域都集中生产并出口其具有比较优势的产品，进口其具有比较劣势的产
跨境电商外文文献综述
跨境电商外文文献综述 (文档含英文原文和中文翻译) 译文: 本地化跨境电子商务的模型 摘要 通过对国际供应链的B2B电子商务交易量的快速增长和伊朗快速增加的跨境交易业务，跨境电商过程的有效管理对B2B电子商务系统十分重要。本文对局部模型的结构是基于B2B电子商务的基础设施三大层，消息层、业务流程层和内容层。由于伊朗的电子商务的要求，每一层的需要适当的标准和合适的方案的选择。当电子文件需要移动顺利向伊朗，建议文件的标准为文件内容支持纸质和电子文件阅读。验证提出的模型是通过案例研究方法呈现一到四阶段的情景。本文试图通过交换商业文件在贸易过程中这一局部模型，实现在全球电子贸易供应链更接近区域单一窗口建设的关键目标。 关键词：电子商务;跨境贸易;电子文档管理;国际供应链
1.简介 电子商务是关于在互联网或其他网络电子系统购买和销售产品或服务。术语B2B（企业对企业），描述了企业间的电子商务交易，如制造商和批发商，或批发商和零售商之间。本文的研究目标是上两个不同国家贸易商之间的通信。今天的世界贸易组织的主要目标之一是建立区域单一窗口，可以提高世界各地的贸易便利化。建立区域单一窗口需要跨境海关，可以有效地交换贸易文件。因此，首先，简化跨境贸易文件的关键在于朝着国家单一窗口移动。然后，区域单一窗口可以授权国家之间的通信。电子商务模型是基于三个主要逻辑层的研究。这三个层消息传输层，业务处理层和内容层。本文的局部模型是一种能够自动交换读取文件的过程。通过与东亚和中东国家的建立区域单一窗口可以在将来得到改善的更多的互操作性，从而建立伊朗国家单一窗口 在本文的第二部分讨论引进国际供应链中的跨境B2B模式所需的基本概念和标准。第三部分介绍在大的模型中引入的组件功能和范围。第四部分讨论了B2B交易层模型的定位，最后结束本文。 2.背景 在本节中，除了了解B2B电子商务在伊朗的情况，还有参考模型的背景等概念以及讨论B2B电子商务跨境模式的本土化。 2.1 B2B电子商务在伊朗 如今伊朗在贸易进程的变现是一个关键的贸易成功点。伊朗和许多其他国家接壤，它的进口和出口过程可以通过公路，铁路，海上和空中的方式来完成。因此，这个国家的中部和战略作用，使得它在亚洲和中东地区货物运输的主要贸易点。今天，在伊朗海关几乎所有的贸易过程通过纸质表格完成，由商务部提供的电子服务仅限于谁该国境内交易的商人。今天，伊朗海关几乎所有的贸易流程都是通过纸质表格来完成的，商务部给出的电子服务只限于该国的商人。介绍了模型试图简化在伊朗交易的跨境电子商务供应链交换电子文件的过程。这里提到的一些系统，由商务部在伊朗的电子服务被提及：进口订单管理系统。贸易统计制度。伊朗法典伊朗。这些电子系统的主要使用，以促进在伊朗贸易过程。这里提到的系统作为独立的贸易者可与建议本文模型在未来的作用。在亚洲的区域性单
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
测量中国的农产品出口的食品安全标准的影响【外文翻译】
外文翻译 原文 Measuring the Effect of Food Safety Standards on China’s Agricultural Exports Material Source: Review of World Economics Author:ChunlaiChen,Jun Yang, andChristopher Findlay 1 Introduction Since 2002, China’s agricultural trade has increas ed rapidly, reaching US$50.44 billion in 2005, and as expectedChina has dramatically increased imports of land-intensive agricultural products, particularly cereals (mainly wheat), vegetable oils and vegetable oilseeds (mainly palm oil and soybeans), and raw materials for textiles (mainly cotton and wool).China has also increased exports of labour-intensive agricultural products, particularly processed agricultural products, but at a slower pace. From 2002 to 2005, the annual growth rate of agricultural imports was 31.53 per cent while that of agricultural exports was 11.65 per cent. As a result, in 2004 and 2005 agricultural imports exceeded agricultural exports and China reported its ?rst two consecutive years of a de?cit in agricultural trade since the 1990s(Chen 2006). From 1992 to 2005, China’s comparative advantage revealed by the net export ratio (NER) in agriculture changed gradually. As shown in Figure 1,China’s revealed comparative advantage in the whole agricultural sector declined, especially after 2002, and since 2004 China’s agricultural sector as a whole has lost comparative advantage in international trade. Also since the 1990s, and especially since the early 2000s, China’s comparative advantage revealed by NER in labour-intensive agricultural products has been declining dramatically (Chen 2006). Figure 1: China’s Revealed Comparative Advantage Indices (NER) of Whole Agricultural Sector and Products by Factor Intensity of Production
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
绿色贸易壁垒与中国的农产品出口外文翻译(节选)
中文3100字，2000单词，1.1万英文字符 出处：Kuppusamy M, Gharleghi B. Green Barriers and China's Agricultural Product Export: Is There Any Relationship?[J]. Asian Social Science, 2014, 10(16):34-41. 原文 Green Barriers and China's Agricultural Product Export: Is There Any Relationship? Kuppusamy, Mudiarasan; Gharleghi, Behrooz Abstract As an agricultural country, the export of China's agricultural products are often suffered the restrictions from the green barriers. The positive green barriers can regulate the agricultural production in China, and promote the agricultural development and international trade; on the other hand, the negative green barriers would increase the cost of trade, trade friction, and prevent the development of international trade. So the research of influence of green barriers on China's agricultural products is very realistic. According to the influence of green barriers on China's agricultural exports, the corresponding countermeasures can be made to deal with the green barriers and improvement of China's competitiveness in the international competition. This study examines the causes, influences and methods of green barriers on China's agricultural products export based on the questionnaires of 200 staffs of agricultural trade companies in Xi'an of Shaanxi province in China. To address this issue, Partial Least Square method is applied and the empirical result shows that there is a positive and significant effect from causes, influences, and methods towards the China's agricultural products export. Keywords: green barriers, agricultural product, export, China 1. Introduction The green barrier is one of the most frequent measures in developed countries from the 1990's (Feng, 2007). As an agricultural country, the export of China's agricultural products are often suffered the restrictions from the green barriers. The positive green barriers can regulate the agricultural production in China, and promote the agricultural development and international trade; on the other hand, the negative green barriers would increase the cost of trading, even cause trade friction, and prevent the development of international trade. Green barriers are also called environmental barriers and green protectionism, which is a new trade barrier since 1990s. Buyers will impose green barriers on sellers' export when the buyers want to protect their own limited resources, human, animal, plant health and ecological environment in the modern international trade. Green barriers take place when importers have strict environmental protection laws and regulations to manage their own environment and technology standards. The green barriers are becoming not only the serious challenges faced by China's agricultural export products but also the biggest obstacle for China's agricultural exports (Yu, 2010). To deal with the green barriers, it is important to identify the causes of green barriers on China's agricultural products export, which are from both import and export countries. The limited agricultural technology of China is one significant cause. Due to the limited agricultural technology of China, the agricultural export products can't meet the high