Welcome Guest ( Log In | Register )

77 Pages « < 56 57 58 59 60 > » Bottom

Outline · [ Standard ] · Linear+

Engineering Simple Guide to Engineering, Read here first before posting new topic

views
     
p3nguin
post Mar 25 2014, 05:23 PM

Getting Started
**
Junior Member
291 posts

Joined: May 2009
From: The United States of America


I would say that SPM math is a pretty poor indicator of how good your math skills are, as it promotes rote memorization instead of understanding. Good unis will probably try to let you understand concepts. Like my first year in uni, it completely blew my mind on how mathematics really was.
Critical_Fallacy
post Mar 26 2014, 03:36 PM

∫nnộvisεr
Group Icon
VIP
3,713 posts

Joined: Nov 2011
From: Torino
QUOTE(CallMeBin @ Mar 25 2014, 03:13 PM)
If define by results, should at least get a B+ ? No idea actually

If that's the case,  rclxm9.gif . Nothing to be worried
A good understanding of Math is required to READ several highly theoretical engineering books. When it comes to design, engineers apply the principle and let the computer solve it. Now, let's do a little test and see to what extent you can understand it. Only a small portion of simple SPM/STPM Math is required. The rest is theoretical logic.

When engineers are to improve the design of a system, or to design a new system, a performance index must be chosen and measured. A system is considered an optimal system when the system parameters are adjusted so that the performance index reaches an extremum, commonly a minimum value. The purpose of design is to realize a system with practical components that will provide the desired time-domain operating performance, x(t), with minimal error. In many designs, we are also concerned with the expenditure of the control action/energy, u(t). For example, in electric vehicles and aircraft, the expenditure of battery energy and fuel and must be restricted to conserve the energy for long periods of travel.

Our goal is to find an optimal control u* that minimizes the following performance index (a.k.a. cost function):

user posted image

where t is the initial time, T is the terminating time, x = x(t) is the current performance state, and L(x,u) characterizes the cost objective.

The Principle of Optimality states, if a control u* is optimal from some initial state, then it must satisfy the following property: after any initial period, the control u* for the remaining period must also be optimal with regard to the state resulting from the control of the initial period.

Now let us consider the current time t and a future time t+Δt closed to t and the control during the interval [t, t+Δt]. Clearly, we can rewrite J(x,t) as

user posted image

Let J* denote the optimal (minimum) cost under optimal control action u*, then by applying the principle of optimality, we have

user posted image

In the above equation, the first term, ∫ L(x,u) dτ can be approximated as user posted image, and the second term, J*(x+Δx, t+Δt) can be approximated by its first-order Taylor expansion:

user posted image

where O(Δt²) denotes the remainder high-order terms (H.O.T.) in the Taylor expansion, which can be omitted if Δt → 0.

Therefore,

user posted image

Since J*(x,t) and (∂J*/∂t) Δt are independent of u(τ) @ interval [t, t+Δt], the above equation can be written as

user posted image

Rearranging the equation gives

user posted image

Letting Δt → 0, then user posted image. Therefore, we obtain the following Hamilton–Jacobi–Bellman equation:

user posted image

This post has been edited by Critical_Fallacy: Mar 26 2014, 03:37 PM
CallMeBin
post Mar 26 2014, 09:10 PM

Regular
******
Senior Member
1,222 posts

Joined: Jan 2011
QUOTE(Critical_Fallacy @ Mar 26 2014, 03:36 PM)
A good understanding of Math is required to READ several highly theoretical engineering books. When it comes to design, engineers apply the principle and let the computer solve it. Now, let's do a little test and see to what extent you can understand it. Only a small portion of simple SPM/STPM Math is required. The rest is theoretical logic.

When engineers are to improve the design of a system, or to design a new system, a performance index must be chosen and measured. A system is considered an optimal system when the system parameters are adjusted so that the performance index reaches an extremum, commonly a minimum value. The purpose of design is to realize a system with practical components that will provide the desired time-domain operating performance, x(t), with minimal error. In many designs, we are also concerned with the expenditure of the control action/energy, u(t). For example, in electric vehicles and aircraft, the expenditure of battery energy and fuel and must be restricted to conserve the energy for long periods of travel.

Our goal is to find an optimal control u* that minimizes the following performance index (a.k.a. cost function):

user posted image

where t is the initial time, T is the terminating time, x = x(t) is the current performance state, and L(x,u) characterizes the cost objective.

The Principle of Optimality states, if a control u* is optimal from some initial state, then it must satisfy the following property: after any initial period, the control u* for the remaining period must also be optimal with regard to the state resulting from the control of the initial period.

Now let us consider the current time t and a future time t+Δt closed to t and the control during the interval [t, t+Δt]. Clearly, we can rewrite J(x,t) as

user posted image

Let J* denote the optimal (minimum) cost under optimal control action u*, then by applying the principle of optimality, we have

user posted image

In the above equation, the first term, ∫ L(x,u) dτ can be approximated as user posted image, and the second term, J*(x+Δx, t+Δt) can be approximated by its first-order Taylor expansion:

user posted image

where O(Δt²) denotes the remainder high-order terms (H.O.T.) in the Taylor expansion, which can be omitted if Δt → 0.

Therefore,

user posted image

Since J*(x,t) and (∂J*/∂t) Δt are independent of u(τ) @ interval [t, t+Δt], the above equation can be written as

user posted image

Rearranging the equation gives

user posted image

Letting Δt → 0, then user posted image. Therefore, we obtain the following Hamilton–Jacobi–Bellman equation:

user posted image
*
Firstly, really thanks so much for your effort !!!!

All the symbols are making me confused .. but I still can understand some of it .. This derivation looks like Differential Equation in STPM

By the way, I was actually worrying about my friend. His Physics is really good, but his maths is just so-so. He has improved a lot in STPM compared to his SPM .. Hoping that he can cope with it if he is to choose Engineering

Critical_Fallacy
post Mar 27 2014, 02:05 PM

∫nnộvisεr
Group Icon
VIP
3,713 posts

Joined: Nov 2011
From: Torino
QUOTE(CallMeBin @ Mar 26 2014, 09:10 PM)
Firstly, really thanks so much for your effort !!!!

All the symbols are making me confused .. but I still can understand some of it .. This derivation looks like Differential Equation in STPM.
Just like the first time you were introduced to x, y, z in geometry and f(x), g(y), h(z) in functions. Once you get used to the math symbols, its not so terrible. Not all engineering books are written in such readable manner. Some authors assume the engineering students have adequate knowledge and backgrounds in Math and Calculus, and so they present only the Performance Index J(x,u), and the Hamilton–Jacobi–Bellman equation. And you'll have no idea how they are related to each other. Some students would argue weakly that,

user posted image

which is erroneous. Therefore, like I emphasized in previous post, a good understanding of Math is required to READ engineering books. And you must NOT refer to only one book but several, so that you can evaluate and select the authors that suit your taste. Are you into medical or engineering? sweat.gif
CallMeBin
post Mar 27 2014, 02:19 PM

Regular
******
Senior Member
1,222 posts

Joined: Jan 2011
QUOTE(Critical_Fallacy @ Mar 27 2014, 02:05 PM)
Just like the first time you were introduced to x, y, z in geometry and f(x), g(y), h(z) in functions. Once you get used to the math symbols, its not so terrible. Not all engineering books are written in such readable manner. Some authors assume the engineering students have adequate knowledge and backgrounds in Math and Calculus, and so they present only the Performance Index J(x,u), and the Hamilton–Jacobi–Bellman equation. And you'll have no idea how they are related to each other. Some students would argue weakly that,

user posted image

which is erroneous. Therefore, like I emphasized in previous post, a good understanding of Math is required to READ engineering books. And you must NOT refer to only one book but several, so that you can evaluate and select the authors that suit your taste. Are you into medical or engineering? sweat.gif
*
Really have to take time to comprehend the symbols ..

Yeah, one book is not enough, learned this in STPM

I'm not into both, but will prefer engineering as I'm good(not sure whether I like) in Maths and like Physics(discovered this when SPM is just around the corner)

Anyway, I've chosen my path though, I'm going for Liberal Arts biggrin.gif
bandit94822
post Mar 27 2014, 09:02 PM

Casual
***
Junior Member
342 posts

Joined: Oct 2009
QUOTE(CallMeBin @ Mar 25 2014, 01:26 PM)
Is it true that engineering requires STRONG mathematical skills ?
*
let see.... SPM maths u can do by understanding it... but engineering maths its kinda like history only this time with numbers and symbols.

Since most of the lecturer will only giv u the theory without letting u know what it is used for. Unless u are lucky and got the good ones....
Carl Johnson
post Apr 1 2014, 02:21 PM

Getting Started
**
Junior Member
232 posts

Joined: Mar 2010


hi ther, i am engineering student from mmu 3rd year....hehe
HillYap96
post Apr 1 2014, 02:49 PM

Getting Started
**
Junior Member
84 posts

Joined: Mar 2014
Can anyone assist me ? Which colleges have material engineering sad.gif ?
HillYap96
post Apr 1 2014, 05:10 PM

Getting Started
**
Junior Member
84 posts

Joined: Mar 2014
Engineering Diploma holders of the School are exempted from relevant papers in the BEM/IEM Examination, what does this mean?
quovadis123
post Apr 1 2014, 05:29 PM

Keys
*******
Senior Member
2,882 posts

Joined: Oct 2009
From: Land of Denial
QUOTE(HillYap96 @ Apr 1 2014, 05:10 PM)
Engineering Diploma holders of the School are exempted from relevant papers in the BEM/IEM Examination, what does this mean?
*
QUOTE
The IEM/BEM Graduate Examinations is for assessment of candidates for admission to Graduate membership of The
Institution of Engineers, Malaysia.

This Graduate Examination is organised by The Institution of Engineers, Malaysia and supported by the Board of Engineers, Malaysia.

The IEM/BEM Graduate Examinations is conducted solely to comply with the requirements for Graduate
membership of The Institution of Engineers, Malaysia and hence to registration as Graduate Engineers with the
Board of Engineers, Malaysia.

The objective of holding the IEM/BEM Graduate Examinations is to provide an opportunity for Malaysians to
achieve professional status through local professional examinations.


Meaning that, students do not need to take this examination from that school.
The reason maybe you will continue the study for degree, and the degree is accredited by BEM.
l4nc3k
post Apr 1 2014, 08:29 PM

Nerd
*****
Senior Member
968 posts

Joined: Aug 2012
From: Subang Jaya


QUOTE(bandit94822 @ Mar 27 2014, 09:02 PM)
let see.... SPM maths u can do by understanding it... but engineering maths its kinda like history only this time with numbers and symbols. 

Since most of the lecturer will only giv u the theory without letting u know what it is used for. Unless u are lucky and got the good ones....
*
partially agree with this.
Lecturer in general (especially those in Malaysia, no offense) suck vmad.gif

And regarding engineering maths.. I take it like a more advanced STPM maths. You can opt to fully understand, and do some practices in order to master engineering maths, or you can take the harder way - kind of 'memorize' the methods to do them.
Critical_Fallacy
post Apr 2 2014, 03:17 AM

∫nnộvisεr
Group Icon
VIP
3,713 posts

Joined: Nov 2011
From: Torino
QUOTE(l4nc3k @ Apr 1 2014, 08:29 PM)
And regarding engineering maths.. I take it like a more advanced STPM maths. You can opt to fully understand, and do some practices in order to master engineering maths, or you can take the harder way - kind of 'memorize' the methods to do them.
Physics and Engineering Maths (Calculus) are particularly required to model the system dynamics in Differential Equations. Because most high-order, nonlinear Partial DEs do not have closed-form solutions, the analysis are usually performed using advanced computational and numerical methods. happy.gif

user posted image
Carl Johnson
post Apr 2 2014, 09:05 AM

Getting Started
**
Junior Member
232 posts

Joined: Mar 2010


for the math skills thing u dun actually need it when in industrial...
HillYap96
post Apr 2 2014, 01:41 PM

Getting Started
**
Junior Member
84 posts

Joined: Mar 2014
what happens if i went for an engineering institution which is not accredited by BEM? eg.TARC
quovadis123
post Apr 2 2014, 02:27 PM

Keys
*******
Senior Member
2,882 posts

Joined: Oct 2009
From: Land of Denial
QUOTE(HillYap96 @ Apr 2 2014, 01:41 PM)
what happens if i went for an engineering institution which is not accredited by BEM? eg.TARC
*
EAC accreditation is to ensure that graduates of the accredited engineering programmes
satisfy the minimum academic requirements for registration as a graduate engineer with the
Board of Engineers Malaysia (BEM) and for admission to graduate membership of IEM.

<<what happens if i went for an engineering institution which is not accredited by BEM?>>
You not able to register professional engineer (Ir title) in BEM.
Your career will be limited to normal engineering. You don't have career advancement in engineering to Ir.
HillYap96
post Apr 2 2014, 02:32 PM

Getting Started
**
Junior Member
84 posts

Joined: Mar 2014
thx
Critical_Fallacy
post Apr 2 2014, 02:36 PM

∫nnộvisεr
Group Icon
VIP
3,713 posts

Joined: Nov 2011
From: Torino
QUOTE(Carl Johnson @ Apr 2 2014, 09:05 AM)
for the math skills thing u dun actually need it when in industrial...
It depends on the engineering industry and the kind of technical position one takes. Most design and analysis are implemented on a computer for processing speed. Sometimes, however, it is useful as well as a rule of thumb to be able to conduct the simple math computation manually with a few parameter variations to check the validity of the computer programs, or to verify the logic of the analytical results.

In machine we trust, maybe, but not each other as human error has been cited as a primary cause or contributing factor in disasters and accidents in industries as diverse as nuclear power (e.g., Three Mile Island accident), aviation (e.g. Eastern Air Lines Flight 401 crash), space exploration (e.g., Space Shuttle Challenger Disaster and Space Shuttle Columbia disaster), and medical malpractice. icon_rolleyes.gif
rainbowasian96
post Apr 2 2014, 04:41 PM

New Member
*
Newbie
2 posts

Joined: Apr 2014
hey i just finished my SPM and i've got fairly good results.. im keen on taking mechanical engineering. may i get suggestions on where i should further my studies and why? smile.gif
rayford
post Apr 3 2014, 04:10 PM

New Member
*
Newbie
2 posts

Joined: Apr 2014
QUOTE(Sky.Live @ Feb 2 2010, 12:56 PM)
Just graduated as Mechanical Engineering, thinking of finding a job while applying for Masters postgrad studies.

Do people usually speciallise their field during masters? izzit advisible to go for the acadamic or research route?
*
Hi,

Having a degree in engineering is really in demand. But experience is more important, if your looking for better future i would suggest find a stable job first, have the feel of doing the hands on engineering and educational advancement is for position level up and can be done after having enough skills on your kind of field.

For further advise lets talk - pm me nod.gif .




Sky.Live
post Apr 4 2014, 10:18 AM

Proctected Species
*******
Senior Member
4,390 posts

Joined: Oct 2004
From: Cheras, Malaysia



QUOTE(rayford @ Apr 3 2014, 04:10 PM)
Hi,

Having a degree in engineering is really in demand. But experience is more important, if your looking for better future i would suggest find a stable job first, have the feel of doing the hands on engineering and educational advancement is for position level up  and can be done after having enough skills on your kind of field.

For further advise lets talk - pm me nod.gif .
*
Did you just replied my post 4 years ago? Interesting to look back what I wrote 4 years back.

77 Pages « < 56 57 58 59 60 > » Top
 

Change to:
| Lo-Fi Version
0.0322sec    0.58    6 queries    GZIP Disabled
Time is now: 28th November 2025 - 07:08 AM