2008年秋冬学期研究生专业英语期末考试试卷参考答案 1.Translate the following words or phrases into Chinese ① Metric
度量 收敛 方差 随机 等价 动态方程 判据、评价标准 测量模型
偏微分方程
在概率意义上，依概率 ② Convergence③ Covariance④ Stochastic⑤ Equivalence⑥ Dynamic equation⑦ Criteria⑧ Measurement Model⑨ Partial derivative equation⑩ In the sense of probability
2.Explain the following symbols in English
① bmthe second order derivative ofb sub m, b
double prime sub m
②
③
④ ABA is equivalent toapproaches aB xiaxi yyx
xthe partial derivative ofwith respective to
a⑤ b
⑥ a‖b
⑦
⑧ 3
f
fintegral between limits b to a a is parallel to the cube root of set aAbXaaAX is contained in b d⑨ abcdedivided by
⑩ e plusminus c multiplied , allequals ,N,s.t aia as ifor any special , there is a respected N,
such that
ai
approaches
a
as i approaches
二、Translate the following paragraphs into Chinese Paragraph A[8 Points]
A subset
d(x,y)M
AX
is said to be bounded if there exists
x,yA
MR
such that
for all.The diameter of A is defined to be
supd(x,y)x,yA.A bounded metric space is one for which X itself is bounded.
Bounded intervals in R are bounded sets.A discrete metric space is bounded (take
译文：一个子集A
d(x,y)M
M1).
X
被称为是有界的，如果存在M
x,yA
R
使得对所有x,y
A
有
。A的半径被定义为supd(x,y)。有界度量空间是指X本
1）
身有界的空间。
在R上有界的区间是一个有界集。离散度量空间是有界的（取M
Paragraph B[8 Points]
In general, it is not required that the reference dynamic model be exactly the same as the truth dynamics or that the modeling parameter
α
be equivalent to the
true modeling vector.This notation is left in place to simplify the derivation of the Kalman filter formulation.A number of innovative approaches have been developed for adapting reference model parameters to improve fidelity(逼真度) with the unknown real-world system model and can be used to enhance filter operation.
译文：一般来说，并不需要参考动态模型与实际动态模型完全相同，或模型参数
a
与实际模型矢量相等。这个记号保留下来只是为了简化Kalman 滤波公式的推
导。大量的改进方法也已被开发出来用于调整参考模型的参数使其与未知的实际系统更接近，这些方法也能被用于增强滤波器运行效果。
Paragraph C[8 Points]
It is commonly held among designers of Kalman filters that the implementation of the
formulas listed above represents only a portion of the effort required to develop an accurate and robust Kalman filter application.Once the dynamics, measurements, and partial derivatives have been coded, the task remained is to tune the noise magnitudes represented in the proce noise covariance Q and the measurement noise covariance R.While the measurement noise can be based in realistic hardware performance specifications, the proce noise is often used as a tuning parameter to ensure that the filter operates correctly.
译文：在Kalman 滤波器的设计者中存在着这样一个共识：对上文所列出来的公式的实现只是用于建立一个精确且稳健的Kalman滤波器应用的一部分努力。一旦动态方程、测量方程和偏微分方程被编码，剩下的任务就是调节在过程噪声方差阵Q和测量噪声方差阵R中表示的噪声幅度值的大小。其中测量噪声的调整可可以立足于实际系统的硬件性能指标，过程噪声常常被用于调节一些参数，以保证滤波处理过程正确。
Paragraph D[8 Points]
Suppose now that
X1
is given as a fixed function of the random
X1
variablesy(t0),...,y(t).Then
is itself a random variable and its actual value is
known whenever the actual values ofy(t0),...,y(t)are known.In general, the actual value of
X1(t1)
will be different from the (unknown) actual value of
x1(t1).To arrive
at a rational way of determiningX1, it is natural to aign a penalty or lo for incorrect estimates.Clearly, the lo should be a (i) positive, (ii) nondecreasing function of the estimation error
x1(t1)X1(t1)
.
译文：现在设X1是随机变量y(t0),...,y(t)的确定函数，则X1本身就是一个随机变量，其实际取值只有在y(t0),...,y(t)确定后才能确定。一般地，X1(t1)的实际值将与（未知的）x1(t1)的实际值不同。为了寻找确定X1的一个合理的方法，自然会为不准确的估计赋予一个惩罚或损失。显然，损失应该是估计误差
x1(t1)X
(t1的)
（i）正定、(ii)非递减 函数。
Paragraph E[8 Points]
Definition:A lead/lag compensator is a rational function of the form
RC(s)
K(1s)1s
1
forK,,
R
with 0,1and
K,0
.It is a lead compensator when and a lag compensator when
K(1s)1s
1.
译文定义：一个超前/滞后补偿器是一个形如
RC(s)
，
K,,R
，0,1，K,
0
的有理函数。当偿器。
1时，它是一个超前补偿器；当1时，它是一个滞后补
三、Try to write an abstract for the following article in about 150 words[20 Points]
TCP/IP Communication for Real-Time and Embedded Systems
（Article deleted here）
Abstract
Using a thermal model of a house as an example, this article describes a method for communicating with other devices via TCP/IP.The method is based on using inexpensive TCP/IP-to-serial-conversion hardware.The real-time system is xPC Target™, a bootable kernel that enables real-time execution of Simulink® models on a separate PC.The target computer is an x86 proceor Intel®/AMD® standard PC that can use commercial off-the-shelf input/output interface cards.
The connectivity approach described here can be used with any real-time or embedded system that supports serial communication.四、Write an Email to a foreign profeor according to following requirements （In about 300 words）
Suppose that you are planning to study for a doctor degree in Sci.abroad, and you have got the email addre of a famous profeor in your intended studying major in an English speaking country.You have never had any contact with this profeor and this is the first time you write to him (her).Now please: Write to this profeor; Introduce yourself to him (her); Apply for a studying permiion, Convince the
profeor that you have a reliable financial support or it is worthy for him (her) to afford you a part time job to improve your financial situation if it is poible.
参考：
Dear profeor:
Thank you very much for your spending a few minutes reading this letter.The only aim that I write this letter is to apply for an opportunity to study for a doctor’s degree under your supervision.
I am a Chinese student.My name is Dongfang Jiang.Now I am studying for my master’s degree in major automation in Northwestern Polytechnical University located in Xi’an, a famous city in the heart section of PR.China.I would graduate in April next year.I am a hard-working student; the appended Resume can help you know more about me and my study.
My parents have promised to provide me fundamental financial support for my studying in your country.I also believe that I have the ability to improve my financial situation through taking part time work if it is poible.
As I want to get a deeper understand of the advanced development of this science direction (which is exactly what your research field), and hope to do some related research work some day, I hope, my wish can be realized.I am looking forward to your kind reply.
Your sincerely
Dongfang JiangNov.20, 2008
