众文网1.求论文英文翻译,急着用,谢谢各位帮忙啦
Principle of Laser RangingAbstract: Since the invention of laser, its amplitude, phase, frequency, polarization direction and propagation direction have achieved high degree of accuracy. This had created new possibilities for applications such as precise ranging. By analyzing the principles and methods of laser ranging, further understanding of laser characteristics and laser's application in ranging could be achieved. Keywords: distance measurement; ranging; laser; phase shift; infrared; pulse。
2.急求一篇焊接类外文文献与翻译啊
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing fusion, which is distinct from lower temperature metal-joining techniques such as brazing and soldering, which do not melt the base metal. In addition to melting the base metal, a filler material is often added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that can be as strong as the base material. Pressure may also be used in conjunction with heat, or by itself, to produce a weld.Some of the best known welding methods include:Shielded metal arc welding (SMAW) - also known as "stick welding", uses an electrode that has flux, the protectant for the puddle, around it. The electrode holder holds the electrode as it slowly melts away. Slag protects the weld puddle from atmospheric contamination.Gas tungsten arc welding (GTAW) - also known as TIG (tungsten, inert gas), uses a non-consumable tungstenelectrode to produce the weld. The weld area is protected from atmospheric contamination by an inert shielding gas such as Argon or Helium.Gas metal arc welding (GMAW) - commonly termed MIG (metal, inert gas), uses a wire feeding gun that feeds wire at an adjustable speed and flows an argon-based shielding gas or a mix of argon and carbon dioxide (CO2) over the weld puddle to protect it from atmospheric contamination.Flux-cored arc welding (FCAW) - almost identical to MIG welding except it uses a special tubular wire filled with flux; it can be used with or without shielding gas, depending on the filler.Submerged arc welding (SAW) - uses an automatically fed consumable electrode and a blanket of granular fusible flux. The molten weld and the arc zone are protected from atmospheric contamination by being "submerged" under the flux blanket.Electroslag welding (ESW) - a highly productive, single pass welding process for thicker materials between 1 inch (25 mm) and 12 inches (300 mm) in a vertical or close to vertical position.Many different energy sources can be used for welding, including a gas flame, an electric arc, a laser, an electron beam, friction, and ultrasound. While often an industrial process, welding may be performed in many different environments, including in open air, under water, and in outer space. Welding is a hazardous undertaking and precautions are required to avoid burns, electric shock, vision damage, inhalation of poisonous gases and fumes, and exposure to intense ultraviolet radiation.Until the end of the 19th century, the only welding process was forge welding, which blacksmiths had used for centuries to join iron and steel by heating and hammering. Arc welding and oxyfuel welding were among the first processes to develop late in the century, and electric resistance welding followed soon after. Welding technology advanced quickly during the early 20th century as World War I and World War II drove the demand for reliable and inexpensive joining methods. Following the wars, several modern welding techniques were developed, including manual methods like SMAW, now one of the most popular welding methods, as well as semi-automatic and automatic processes such as GMAW, SAW, FCAW and ESW. Developments continued with the invention of laser beam welding, electron beam welding, magnetic pulse welding (MPW), and friction stir welding in the latter half of the century. Today, the science continues to advance.Robot welding is commonplace in industrial settings, and researchers continue to develop new welding methods and gain greater understanding of weld quality.焊接是一种制造或雕刻过程联接材料，通常是金属或热塑性塑料，通过使融合，这是从较低温度金属接合技术如钎焊和焊接，这不熔化的基体金属不同。
除了熔化基础金属，填充材料通常加入到接头以形成熔融材料（熔融池），该冷却以形成一个接头，该接头可以是强如基材的池。压力也可结合使用热，或由本身，以产生一焊缝。
一些最好的公知的焊接方法包括：保护金属电弧焊（SMAW） - 也被称为“粘焊接”，使用具有焊剂，防护剂为水坑，它周围的电极。电极支架保持电极，它慢慢地融化。
渣保护不受大气污染熔池。气体钨电弧焊（GTAW） - 也被称为TIG（钨惰性气体），使用非自耗钨电极以产生焊缝。
焊缝区域由惰性保护气体如氩气或氦气免受大气污染。气体保护金属极电弧焊（GMAW） - 通常称为MIG（金属惰性气体），采用的是送丝枪送线以可调速度，并在流动的氩基保护气体或氩气和二氧化碳（CO 2）的混合熔池，以保护它免受大气污染。
药芯焊丝电弧焊（药芯焊丝） - 几乎等同于MIG焊接除了它使用一种特殊的管状焊丝充满通量；它可以用于具有或不具有保护气体，这取决于填料。埋弧。
3.急
On Hong Kong after the reunification of Hong Kong films in the direction of the ups and downs
Abstract:
Hailed as "Oriental Hollywood" in Hong Kong, Asia has created a film of a miracle. 11 handover, Hong Kong has quietly changed many aspects. Hong Kong and the film has undergone enormous changes. Hong Kong's economy is closely related with Hong Kong film, after the handover of Hong Kong's economic ups and downs continue to decline, so after the handover of Hong Kong films must change, must be gone from a stagnant, declining to changes in the transition process, this process is difficult. But after the transformation of Hong Kong films that will usher in a new spring.
Key words: Hong Kong film; regression; development of fusion
4.毕业论文摘要英文翻译
Since our reform and opening to the world, china has been make great strides forward and change greatly in all fields such as economy, culture and politics .when its comes to culture,the strides are showed on the rise of female's educational level and The ratio of female in universities and colleges.even the ratio reach up to 50%.we know that the graduated students is one of the main part of job hunters.The inequalities between the sexes were mirrored in social life ,especially in obtaining employment .
The inequalities between is obvious, most of company would like to choose male instead of female when meeting the same condition interviewee, and female often given lower salary compare with male when doing the same work in the same company according to sex determination. It is worthwhile to note that female are more likely restricted and aggression in gender inequality in obtaining employment.gender inequality effect female's development and future, neglect social integration, harm social cooperation of genders, which lead to consequence seriously such as the lack of coordination between male and female, sound development and the normal operation . the root cause of these problems include sexual discrimination, employing units exist prejudice and angular impression involved in different vocations and some personal reasons from students as professional choice and mental qualities.in order to resolve these problems, we need the public change those angular impressions, employing units
broad vision with development. Meanwhile, as students, who need build health personality and learn more useful knowledge.
The paper will analyze and discuss
the phenomenon of gender inequality of universities and college students in china ,and
conclude some effective Issues and Countermeasures
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