FEM class notes

Dear all,

I found the FEM class notes in the below web address.

http://www.uni-kassel.de/~w_110800/publications/lectures/detlefkuhl_fem1.pdf

Regards

Niraj Kumar Jha

Gurgaon unveiled

Gurgaon, the so called metropolitan city, it comes under Haryana state. I am staying here since last 75 months and divulge the secret of this city. On the very first day, I noticed several skyscraper malls with slight parking space, traffic around all places, contaminated breathing air and no shelter to avoid the striking daylight. With the help of my friend somehow I reached my designated location. I would recommend all of you to get the travel routes from the two landmarks, Kapashera and Iffco chowk as it’s a bit cheaper to travel from the local auto easily available there than hiring a taxi or auto-rickshaw.

The most urban land is occupied by DLF along with HUDA and the rest is dedicated to the rural society. This is the only city that I suppose where you can naturally observe rural people driving cars like BMW, Mercedes etc. rashly .Almost all sectors are immensely occupied by buildings with improper drainage system. And when it rains, I would recommend you to start early in the morning if you are going for an important task because traffic due to logged water can spoil your whole planning. Middle class families prefer to stay in sectors rather than DLF or Ansal API. If anyone is planning to stay for more than a year it’s good to buy a bike to avoid parking problems.

A substantial section of youth can be noticed in Gym center and also in the shopping malls. Gym centers are equipped with advanced computerized weight loss machines affordable for affluent people only. I was saddened once investigated that no high-tech library is available in Gurgaon. Hardly any universities are there where outsiders can go for reading novels or magazines. Yes, IIT Delhi allows outsiders but it’s far away from my current address. I used to utilize Reliance store of the Ambience mall where you can sit with a coffee for long hours.

There are a few exclusive locations in Gurgaon where you can enjoy along with your friends and family members. Kingdom of dreams is one of the best entertainment places which bring live entertainment shows and theatre. It is often visited by many film stars too like Shahrukh Khan etc. Fun N Food village is an amusement park for people of all ages that includes a astounding water park and various thrilling rides. Nearby spots suitable for photography are Sultanpur bird sanctuary and Qutub Minar.

Newfangled Metro lines connect to Delhi and NCR regions making traveling very relaxing but the peaceful Metro journeys can only be granted during weekday’s unofficial times. Traveling through Kapashera bus route is a cumbersome task due to passenger volumes but still if you want to try, take bus number 729 to reach New Delhi.

There are many varieties of street foods available which you can enjoy specially after dusk. Momos, Noodles and Spring roll are a few of them. Dhana choga, Om Sweets, Chaupal, Barbeque nation and Mainland china are the famous restaurants available for spicy foodstuffs. The beer N wine shop is available ubiquitously. Carlsberg is the one which I enjoyed drinking throughout my stay here. Caffe Mocha close to the HUDA metro station is very nice spot to get an experience of varieties of Hukka.

Hindu temples are available in almost all the regions run by mostly UP & Bihari pandits but globally renowned temples are present in Delhi like the Aakshardham temple, Iskon temple and Lotus temple etc.

This city is very costly and pleasure life is guaranteed only when you have got plenty of money to spend on these. As per my experience I would recommend people who have spent their childhood in small industrial city, not to come here to try your luck as you’ll be disappointed due to environmental, social and economical factors. For people employed in MNCs located in Gurgaon, it’s better to stay somewhere in Delhi to avoid lackluster life.

Modeling of McPherson System

The McPherson strut suspension is a very popular mechanism for independent

front suspension of street cars and was invented by Earl McPherson in the 1940 . It was first introduced on the 1949 Ford Vedette, and also adopted in the 1951 Ford Consul, and then

become one of the dominating suspension systems because it’s compactness

and has a low cost.

Let's learn to model this system as an inverted slider mechanism.

This image represents the kinematics model of McPherson suspension system.

Let's assume

length of link 1 = a

length of link 2 = b

length of link 3 = c

length of link NB = d

Considering M = (0,0) we can find out the other co-ordinates

A= (b cosθ2, b sinθ2)

N= (a,0)

B= (a + d cosθ4, d sinθ4)

Coordinates of A in terms of link 3 (c) = (a + d cosθ4 -c sinθ4 ,d sinθ4-c cosθ4)

b cosθ2 = a + d cosθ4 -c sinθ4

b sinθ2 = d sinθ4-c cosθ4

These two equations can be solved easily.

Active Vibration Control

Yesterday while solving a problem of cramster.com,I successfully modeled a quarter car suspension which can control the vibration actively.Refer below diagram.

m1 = Sprung mass

k1 = spring constant of spring attached between sprung and unsprung mass

d1 = damping co-eff of damper attached between sprung and unsprung mass

q1 = displacement of sprung mass

m2 = Unsprung mass

k2 = spring constant of tire

d2 = damping co-eff of tire

q2 = displacement of unsprung mass

z = displacement of tire

Writing an equation of motion for sprung mass m1, we get

m1 * d^2/dt^2 *q1 + k1 ( q1 - q2) + d1 *d/dt ( q1 - q2) = u

Similarly writing an equation of motion for unsprung mass m2, we get

m2 * d^2/dt^2 *q2+ k1(- q1 + q2) + d1 *d/dt(- q1 + q2)+ k2 ( q2 -z) + d2 *d/dt ( q2 - z ) + u=0

These two equations can easily be solved using MATLAB.

The active control is generated here with non-negligible time lag by using a pneumatic actuator.An active suspension systems offer the possibility to vary the damper characteristics along with the road profile and thus far better than passive suspension.

The most beautiful words ever written, spoken, read...

It's no wonder it's called the Canticles of Canticles.

When I first saw her, I’d make up free verse and write them out. She is a beautiful, smart, intelligent girl.A couple of days ago,i found a lovely poem for my beloved from the book "The Song of Solomon".

"I slept, but my heart was awake.

Hark! my beloved is knocking.

'Open to me, my sister, my love,

my dove, my perfect one;

for my head is wet with dew,

my locks with the drops of the night.'

I had put off my garment,

how could I put it on?

I had bathed my feet,

how could I soil them?

My beloved put his hand to the latch,

and my heart was thrilled within me.

I arose to open to my beloved,

and my hands dripped with myrrh,

my fingers with liquid myrrh,

upon the handles of the bolt.

I opened to my beloved,

but my beloved had turned and gone.

My soul failed me when he spoke.

I sought him, but found him not;

I called him, but he gave no answer.

The watchmen found me,

as they went about in the city;

they beat me, they wounded me,

they took away my mantle,

those watchmen of the walls.

I adjure you, O daughters of Jerusalem,

if you find my beloved,

that you tell him

I am sick with love."