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The other day I was reminiscing with one of my old friend about our earlier days and how did I get my teaching job (also the first and only job in my life). He thought my experience is worth retelling as a blog article to illustrate how luck, preparation, and initiative help in one’s career. Thus at the risk of blowing my own horn (自吹自大), here is my experience as a case study for young people starting out.
In an earlier blog article http://www.sciencenet.cn/m/user_content.aspx?id=11577 I reported my own experience of ph.d study at Harvard and my first publication. These events were intimately connected with how I got my first job. In the interest of continuity of reading and thought, I reproduce part of the article here before my main discourse. “. . . ..During 1959-1960 when I started at Harvard intending to do a thesis on control and system theory, Harvard had essentially no one in the subject area. I was lured to graduate study there by a pamphlet entitled Computer-Control Engineering issued by the Harvard computation laboratory under Howard Aiken (note: Howard Aiken was generally considered to be the Father of digital computers and built the Mark series of computers during 1944-1955. However, his views on computer control was largely misdirected. And by the late fifties he was nearing retirement no longer active in research even though he still had a great reputation.)
I quickly found out that there was really no competence on the subject of control at Harvard. One junior faculty in
the subject was leaving since he was denied tenure. Only one other lecturer, a recent graduate, was on a year-to year appointment to teach a course on feedback control. Thus, there was essentially no one to guide me. In desperation, I begin to read any papers I could find on control being published at the time. I came across a paper by R.E. Kalman and J. Bertram on dead beat control the problem of controlling a general order linear sampled data system from any initial condition to zero in n steps where n is the dimension of the system. Associated with the solution of the problem was a condition then known as the Kalman-Betram condition. After studying the problem on my own,
I came to realize that the KB condition really is a condition on linear independence in algebra. So, I wrote up the idea together with an application and submitted it as an extension to the Kalman paper.
Simultaneously, I wrote to Kalman asking for more of his work. At the time, Kalman was not yet famous (his famous Kalman filtering paper was still one year away from publication).
He was appreciative that someone, a graduate student, had studied and was interested in his work. He not only sent me several of his preprints, but also recommended my extension of his work for presentation and publication, at the first American Automatic Control Conference(AACC) in 1960, It is there I first met Kalman. During a conversation, he realized that I had thoroughly studied his work and was in fact one of the few people at that time appreciated his contribution (Note: At that time almost all the well known work on control were done in the so-called frequency domain utilizing Fourier and Laplace transform methods. Kalman’s approach using time domain and differential equation model for dynamic system was very unorthodox and viewed with suspicion by the establishment. But for a graduate student who has not been brain-washed by orthodoxy, new ideas were easier to absorb.) Kalman further invited me to co-author a paper with him considerably generalized the idea of linear independence in dynamic systems to the concept of “controllability” – a fundamental idea in control. The paper quickly became a classic of the field. I also benefited from getting an advanced prepublication copy of the book by R. Bellman – Adaptive control, a guided tour - from my classmate , Stuart Dreyfus who was working as a programmer for Bellman at that time. I learned a great deal before the general public from the book. These two things more than any other enabled me to finish my thesis, and in addition you can say my career in the field was launched. . . . .”
At the AACC I mentioned above, my paper was scheduled in the same session which Kalman chaired and which his famous and Draper prize winning filtering paper was first presented. As chairman and session organizer, he scheduled his paper last both as a courtesy to other speakers and as 压台戏. This was fortunate for me since otherwise the audience would have been totally distracted by the long debate Kalman had with several control experts after the presentation of his paper (which was poorly or not understood at the time). I was the third speaker after two conventional control papers and was introduced as an unknown graduate student not yet finished with his thesis. I spent a great deal of time preparing and rehearsing my presentation. Thus, my presentation was like a breath of fresh air from an unheard of junior student. Furthermore, I also anticipated and prepared for several of the questions the audience might have and was able to answer them succinctly and clearly. This impressed the audience which included many leading scholars in the audience (these facts were later on made known to me over the years but unknown to me at the time). Among them was Prof. Gordon Murphy, the chairman of the electrical engineering department of Northwestern University in Chicago. He was moved to make an appointment with the dean of my school and told the dean that he wants to hire this Harvard student whom he had just met and heard (he did follow up with a very good formal offer to me).
Simultaneously, this first attendance at a national meeting of the field opened my eyes to the important revolution taking place in my discipline. I decided to write a position paper to a couple of Harvard professors about the status of the subject of control systems and that Harvard should be cognizant of this development. These fortunate combinations of occurrence of events made Harvard to look at me differently as a routine graduate students and decided to offer me an assistant professorship at the same time with the lecturer who signed my thesis. However, I was very much taken with the prospect of working in the aerospace industry on the Apollo moon project with a salary much higher than academia offered. It was not an obvious choice that I should choose Harvard. For whatever reasons, right or wrong, my wife advised me that I should consider academia which turned out to be the correct decision for the rest of our lives by hindsight.
I detailed this sequence of events and decisions to illustrate how luck, preparation, initiative, advice, and being able to seize the opportunity when it comes play a role in one’s career and life. At least in America, you have a chance to rise by your own merit, do not have to depend on KwanXi, family origin, nationality, or trickery, engage in friendly competition, and still be true to yourself. Despite current ills, I am hopeful that China can achieve the same in due time.
我是如何获得我的终身职业的
前几天,我与一位老朋友谈到过去的往事,谈到我是如何得到教师工作的(也是我生命中第一份和唯一的一份工作)。他认为我的经历值得以博文的形式复述出来,阐释在一个人的职业生涯中,运气、准备和主动性的作用。因此,冒着自吹自擂的风险,在这里我向年轻人谈谈我个人的一些学习经验。
在我之前的一篇博文中(见http://www.sciencenet.cn/m/user_content.aspx?id=11577)我谈到了我在哈佛读博期间的一些经验和我的第一篇论文。这些事件都与我获得第一份工作密不可分。出于阅读和思考的连续性的考虑,在我谈本文的主要观点之前,先复述那篇博文的部分内容。
我是在1959年至1960年开始在哈佛学习的,目标是做一篇有关控制和系统理论的博士论文。哈佛其实基本上没有这个领域的专家。我之所以选择了哈佛做研究生是受了一本名叫《计算机控制工程》的小册子的诱惑,这本小册子正是由大名鼎鼎的Howard Aiken领导下的哈佛计算机实验室撰写的。(注:Howard Aiken通常被认为是电子计算机之父,1944至1955年之间他建造了Mark系列计算机。但是他关于计算机控制的观点基本上是错误的。到50年代后期的时候,他差不多快要退休了,不怎么搞研究了,但是仍然声名显赫。)我很快发现哈佛在控制领域做得并不出色,这个领域的一位年轻教授因为没有拿到终身职位,正准备离开哈佛,而另外一位是讲师,刚刚毕业不久,跟哈佛的合同是一年一签,教授一门反馈控制课程。所以基本上没人能指导我。绝望中,我开始拼命读当时发表的控制领域文献,碰巧看到一篇R. E. Kalman和J. Bertram合写的文章,是关于无差拍控制的问题(dead beat control – a problem of controlling a general nth order linear sampled data system from any initial condition to zero in n steps.)
与这个问题相关的是一种叫做“Kalman-Bertram Condition”的状态。我自己研究了这个问题以后,发现K-B状态其实是一个线性代数中的线性无关性状态。然后呢,我就把我的想法及其应用一起写下来,作为对Kalman论文的发展投稿了。与此同时,我写信给Kalman,请他提供更多的文献资料。当时Kalman还不是很有名,(他那著名的Kalman滤波的论文一年以后才发表)。他很高兴有人,而且是个研究生,仔细研究了他的工作,对他的工作怀有浓厚的兴趣。他不但寄给我一些正在撰写的论文的预印本,而且还把我对他工作的推进推荐给1960年召开的第一届美国自动控制大会(AAC),让我去做报告,发表论文。正是在这次大会上,我第一次见到了Kalman。谈话中,他发现我真的彻底地研究了他的工作,而且实际上是当时很少的几个真正认识到他的工作重要性的人之一。(注:当时几乎所有控制方面的著名工作都在应用了Fourier与Laplace变换方法的所谓频域领域。Kalman的方法则在动态系统上使用了时域和微分方程模型,这在当时是非常离经叛道的,主流观点对此质疑很多。但是因为我还是个研究生,还没被主流观点洗脑,所以更容易吸收这些新想法。)Kalman还邀请我和他合写了一篇文章,将动态系统中的线性无关性的想法大大拓展,提升为“可控制性”(controllability)——现在这已经是控制论中的一个基本概念了。这篇文章很快成为该领域的经典。此外,我的一个同学Stuart Dreyfus当时正在帮R. Bellman编程,我从他那里得到了Bellman撰写的Adaptive Control: A Guided Tour一书的预印本,因此能够在其他人之前从中学到很多东西。这两件事比其他任何因素都更能帮助我完成了博士论文,而且可以说我的事业由此起步。
在我上面提到的AAC大会上,我的论文收录在Kalman担任主席的会议中,而且他的那篇著名的获德雷珀奖滤波论文也是在该会议上首次公开露面。作为主席和会议组织者,出于对其他演讲者的礼貌及作为大会压轴戏的考虑,他将他的论文放在会议的最后。这对我来说是很幸运的,因为不这样的话,Kalman演讲后与其他几个控制论专家长时间的辩论将会搞得观众心烦意乱(他的这篇论文当时被理解得不深,或根本没被理解)。我是第三个演讲者,在我之前的两位演讲者论文主题是传统控制论,当时我还是一个还未完成毕业论文的不起眼的研究生。会议前我曾花了大量的时间准备并演练我的演讲。因此,我这个晚辈学生的演讲有点给人耳目一新的感觉。此外,我还预先准备了好几个问题应对听众的提问,从而能够对他们的问题给予简洁而清晰的回答。这给包括很多顶尖学者在内的听众们留下了深刻的印象。(我当时并不知道,很多年之后我才知晓。)美国西北大学电子工程系主任Gordon Murphy就是当时的听众之一。他被我在大会上的表现所打动,随后约见了哈佛的系主任,表示他想要聘请我这个他初次谋面的哈佛学生(他后来真的给了我一个非常正式的offer。)
同时,这是我生平第一次参加系统控制领域的国家会议,大大开拓了我的视野,看清了我所在领域内正在发生的重要的革命。我决定写一篇文章给哈佛的几个教授阐述控制系统学科的地位,我认为哈佛应该认识到这个发展。这一系列幸运事件使哈佛对我这个平凡的研究生另眼相看,而且决定给我提供一个助理教授职位,让我与签署我毕业论文的讲师一起工作。但是,当时进入航空航天领域阿波罗登月项目的工作前景使我十分心动,因为这一领域的工资要远远高于学术界。我是否应该选择哈佛很难抉择。出于一些说不清对错的原因,我妻子建议我应该考虑留在学术界,后来我们认识到这个选择其实是正确的。
当然,当一扇门为你开启之后,剩下的还要取决于你的付出。当你做出了职业选择之后,在接下来的五年中,你依然面临着着激烈的全球性竞争。(见一个美国教授的生活1、2 http://www.sciencenet.cn/m/user_content.aspx?id=239719,http://www.sciencenet.cn/m/user_content.aspx?id=1808和补充文章http://www.sciencenet.cn/m/user_content.aspx?id=33550))在哈佛,我和同事(签署我论文的讲师)一开始就清楚地知道这一点——我们中至多一个人能留下来。这是一场诚实、友好但残酷的竞争,我们现在仍然是很好的朋友。
我详细描述了这一系列事件和抉择是为了说明,运气、准备、主动性、建议,以及当机会来临时有能力抓住在一个人的职业和生活中扮演了怎样的作用。至少在美国,你有机会通过你自身的优点获得提升,进行友好的竞争,做真实的自己,而不需要依靠关系,家庭出身,国籍或者耍花招。尽管中国当前存在种种弊病,但我对中国及时达到这一点充满希望。 (科学网 陈丹/译 梅进/校)