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BIML and BIPM Directors
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作為一名機(jī)械工程師，對(duì)于動(dòng)力學(xué)，首先浮現(xiàn)在我腦海的是它是應(yīng)用物理學(xué)的一個(gè)分支，特別是在經(jīng)典力學(xué)領(lǐng)域中關(guān)于力和扭矩及其對(duì)運(yùn)動(dòng)影響的研究方面。動(dòng)力學(xué)的研究分兩類：線性的（如力、質(zhì)量/慣性，位移，速度，加速度和動(dòng)量）和旋轉(zhuǎn)的（如轉(zhuǎn)矩、慣性矩/轉(zhuǎn)動(dòng)慣量、角位移、角速度、角加速度和角動(dòng)量)。通常，物體同時(shí)做線性和旋轉(zhuǎn)運(yùn)動(dòng)。
許多儀器在“動(dòng)態(tài)”法制計(jì)量學(xué)中被應(yīng)用，下面舉例說明：
●自動(dòng)稱重儀器，可以對(duì)運(yùn)動(dòng)物體進(jìn)行稱重； ●電能表，測(cè)量電子流； ●各種類型的測(cè)量水流量的儀器； ●測(cè)量其他各種液體流量和氣流量的儀器； ●計(jì)價(jià)器。
然而在英語中，“動(dòng)態(tài)”一詞不僅與運(yùn)動(dòng)有關(guān)，還與變化有關(guān)。
一個(gè)運(yùn)用在多種不同科學(xué)（如計(jì)量）和工程學(xué)科中的例子可以突顯這個(gè)連續(xù)性的和富有成效的“變化”，那就是太空旅行。1903年12月17日，萊特兄弟研制出第一架可控制的、具備持續(xù)自動(dòng)推進(jìn)功能的飛機(jī)。1957年10月4日，蘇聯(lián)將人造衛(wèi)星1號(hào)送入軌道，這是地球的第一顆人造衛(wèi)星。1969年7月20日，在美國(guó)的阿波羅11號(hào)任務(wù)中實(shí)現(xiàn)了第一次載人登月。1998年，國(guó)際空間站（ISS）的第一個(gè)組件，或可居住的人造衛(wèi)星，投入低地球軌道。2012年，美國(guó)國(guó)家航空航天局（NASA）的好奇號(hào)探測(cè)器成功登陸并對(duì)火星進(jìn)行探索。最近2014年11月，歐洲航天局的羅塞塔任務(wù)讓菲萊探測(cè)器著陸在彗星上。
計(jì)量領(lǐng)域發(fā)生了巨大的變化，有關(guān)某些國(guó)際標(biāo)準(zhǔn)單位的定義工作，諸如對(duì)于千克的新的定義已接近完成。為其他國(guó)際標(biāo)準(zhǔn)單位作出定義而改進(jìn)設(shè)備的研究持續(xù)獲得成功。
計(jì)量學(xué)如人類文明一樣古老，但它仍在持續(xù)變化；并且還能看到它在加速變化，它仍然是動(dòng)態(tài)的。參與到被我們稱之為“計(jì)量”的工作的時(shí)刻是非常令人著迷的。
Measurements in a dynamic world
As a mechanical engineer, the first thought that comes to my mind is that dynamics is a branch of applied physics, specifically the field of classical mechanics which is concerned with the study of forces and torques and their effect on motion. The study of dynamics falls under two categories: linear (quantities such as force, mass/inertia, displacement, velocity, acceleration and momentum) and rotational (quantities such as torque, moment of inertia/rotational inertia, angular displacement, angular velocity, angular acceleration and angular momentum). Very often, objects exhibit both linear and rotational motion. Numerous instruments are utilized in “dynamic” legal metrology; some examples are:
- automatic weighing instruments, which can weigh items while in motion,
- electricity meters, which measure of the flow of electrons,
- various types of instruments that measure the flow of water,
- the flow of various other liquids and gases, and
- taximeters.
In English, however, the word “dynamic” relates not only to motion but also to change. One example that highlights this continuous and productive change which encompasses many different sciences (including metrology) and engineering disciplines is space travel. On December 17, 1903 the Wright brothers made the first controlled, self-powered sustained flight. On October 4, 1957, the USSR placed in orbit the Sputnik 1, the first artificial satellite of Earth. On July 20, 1969, the first manned lunar landing was achieved by the United States’ Apollo 11 mission. In 1998 the first components of the International Space Station (ISS), or habitable artificial satellite, were put into low Earth orbit. In 2012, NASA’s Curiosity succeeded in landing on and exploring Mars. More recently in November 2014 the ESA’s Rosetta mission landed its Philae probe on a comet. In the metrology community we are now seeing significant changes related to the definition of certain SI units as work on the new definition of the kilogram nears completion. Research continues to be successful in refining values and equipment used in the definition and the mise en pratique of other SI units. While metrology, the science of measurement, is as old as human civilization it continues to constantly change; it continues to see forward acceleration and it continues to be dynamic. It is truly a fascinating time to be a part of this very dynamic work that we call “metrology”.
Measurements in a dynamic world
When we reflect on the rapid pace of change in the 21st century, we may say that “the only thing that is constant is change itself”. The needs for metrology, and how these needs are met, are no exceptions; it is a challenge to bring the benefits of a stable and accurate measurement system to a dynamic world. Many of the needs of society are met by new technologies, and it is essential that stable and accurate measurements are available to underpin them. The accurate knowledge of dynamic quantities is pivotal to progress in high technology whether it is the high-speed movements in a disk drive, the variations in supply and demand from renewable energy sources on electricity grids, or the drive for environmental improvement and fuel efficiency in the aerospace industry. Dynamic quantities also play an increasing role in established industries, such as the dynamic weighing of trains and trucks, and the monitoring of vibration and impact arising from the tyres and engines of cars. These applications of dynamic measurement bring particular challenges. Linking highly accurate long-term stable standards to dynamic in situ measurements in everyday applications is difficult and itself requires great innovation. Adapting our measurement capabilities to a dynamic world requires other steps too. The need to ‘future proof’ the International System of Units (the SI) is one of the key drivers for the redefinition planned for 2018. The changes will ensure the benefits of greater universality of the world’s measurement system, and open new opportunities for scientific and technological advances in the future. We all need dynamic people in dynamic organisations to address the challenges of measurement in a dynamic world. | 
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