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Friday, December 30, 2011

Google Surprises

Google is the most used search engine around the world. It gained its popularity due to its new clatter free approach to searching the internet and its unique result sorting algorithms. While doing the best at what it does, the search engine also has some lesser known "easter eggs". Listed below are some of them.
1. Tilt
Type the word "Tilt" or "Askew" in the search box to find google to show its meaning quite literally.
tilt

askew
2.Let it snow
Introduced as a seasonal special, typing in Let it snow" will cause snow fakes to come down and create frost on the browser window. The search button turns to a 'Defrost' button while also allowing you to wipe your screen by dragging the mouse pointer around.
Let it snow
3.Once in a blue moon
Google Calculator is very useful tool to many people. Finding the value of physical constants, or unit conversions have become so much easier with Google's inbuilt calculator. But what if you want to know the answer to a somewhat childish question, like "What is the loneliest number?" or want to physically quantify the frequency indicated by the phrase "Once in a blue moon", Simply type it in Google!
loneliest Number

Conversion of Once in a blue moon to Hertz
4.Recursion
Type in the word recursion in the Google search box and you will find under "Did you mean" the exact same word link. Clicking this apparently corrected word link will bring you back to the same results with the same "Did you mean" link, thus making you 'feel' the meaning of recursion..
Recursion

5. Google Gravity
Although not an original Google creation this is also worth checking out. Type Google gravity and hit the "I am feeling lucky" button, or Click on the first link out of the search results. This will take you to a Google page where the effect of gravity is very apparent. It also allows you to search using this interface and the search results will also obey the laws of gravity!
Google Gravity


Wednesday, December 28, 2011

New year in Hospital

I spent the fist few days of this year-2011 in hospital. Due to severe headache and fever I was hospitalized because the doctors suspected it was Sinusitis, right at the beginning of the new year. Later however the doctors found that it was the flu. To make things worse, I was supposed to sit for my end semester examinations two weeks later. I was discharged after one week.
This time around I got the feeling that I may have to end up in hospital just like before when I was hit with high fever and a headache yesterday. I didn't wan't it to end up like last time, so I went to the doctors immediately and got some antibiotics. I feel better today and I am recovering. I just hate to get hospitalized...

Monday, December 26, 2011

Places to visit in the Jaffna Peninsula

Jaffna is one of the uniquely picturesque places in Sri Lanka. Situated in the northern part of the island it also a geologically unique landmass of the country. The rocks present in Jaffna are mainly sedimentary rocks like limestone. There are no igneous rocks to be found anywhere.
There are several places worth visiting in the Jaffna Peninsula. The Jaffna Library, the Nallur Kovil are attractions that are situated close to the town while Places like Naagadeepa, Casurina Beach are about an hours drive away. These places are situated in the islands that are part of the Jaffna Peninsula. While some of the islands are connected by roads across the shallow oceans and lagoons, Some islands such as Naagadeepa are separated from the land and a boat service is available to travel to these parts.
Point pedro, The nothern extremum point of the island of Sri Lanka is also situated in the Jaffna peninsula.
While having several places of historic interest, the landscape of the Jaffna peninsula alone comprising of the vast lagoons, islands and coastal vegetation a treat to the senses.
entrance to Casurina Beach
Casurina Beach

Point Pedro

Jaffna Town

Friday, December 9, 2011

A new place to hang around in Colombo

An old dutch hospital was converted into a shopping precinct and opened to the public on the 2nd of December 2011. It is a calm and quiet place and an excellent place to relax while having a cup of tea or coffee. It is situated right opposite the World Trade Centre.
The renovation of the old dutch hospital was done while making sure that the original architecture remains unchanged. This gives the "shopping precinct" an antique and an aesthetically pleasing look. The shopping precinct includes a few coffee shops, restaurants clothing and accessory outlets and textile and handicraft stalls.


more information : http://www.news.lk/news/sri-lanka/912-old-dutch-hospital-converted-into-a-shopping-precinct-in-colombo

Thursday, December 8, 2011

Majestic Superior 3D movie theatre

As soon as I got to know about the first ever 3D movie theatre to open in Sri Lanka, I rushed over to watch "The Three Musketeers " in 3D. Although the movie had a quite simple plot, it was very enjoyable in 3D.  I didn't wan't to book the tickets online, but thought later that it would have been a better option because within minutes after the tickets were issued the theatre was full. Luckily being in the front of the queue I managed to get seats where I wanted.
The Superior 3D movie theatre is one of the four theatres that make up the newly constructed Majestic Cineplex. While the old theatre is also part of this Cineplex it has been named "Platinum". The other three, "Ultra", "Gold" and "Superior 3D" are situated on the 5th floor.



The tickets for the Superior 3D are priced at Rs600. The seats are comfortable and it is a medium sized theatre. This fresh new addition will be a boost to Sri Lanka's entertainment industry and is great news for moviegoers.

First ever 3D movie theatre in Sri Lanka-Majestic Superior 3D

I've been waiting to watch a 3D movie in Sri Lanka and now it's possible with the new Majestic Superior 3D movie theatre. The superior 3D theatre is one of four theatres that make up the Majestic Cineplex. The old theatre has been named Platinum and the names of the other two are, Ultra and Gold. This cineplex was opened to the public on the 2nd of December 2011.
image from -dailymirror
For further information : http://www.dailymirror.lk/entertainment/151-entertainment-main/15244-majestic-cineplex-opens.html


Tuesday, December 6, 2011

Super 8 and Crysis

I'm not sure whether I'm the only one who noticed it, but I found a lot of similarities between the movie "Super 8" and the video game "Crysis". The scenes nearing the end of the movie especially ones in the alien's lair reminded me of the games Crysis and Crysis Warhead. Even the story is somewhat similar to that of Crysis in which an alien is discovered, although the alien is not very friendly and nice to kids like in Super 8 ;) It's as if the creators of the movie were inspired by the events and the scenes in the games. It is a fairly good movie however...
Super 8 -image from Wikipedia-

The unseen side of Graphite mining

Graphite is a major export of Sri Lanka and is mined at two places in the country namely, Kahatagaha and Bogala. Sri Lanka is the only country in the world where crystalline graphite or lump(vein) graphite is mined underground. The graphite such mined is also of very high quality and is very pure-99%pure C.

Graphite -image from Wikipedia


In a very brief report I wrote about the graphite mining practices in Sri Lanka, based on an investigation carried out at the Graphite mine in Kahataga, I concluded that no overall damage to the environment was done. This was because graphite being a natural product and is essentially pure carbon which is not a toxic substance, it cannot do any harm to the environment. However further research and more thought put into the matter shows that I couldn't have been more further from the truth. Graphite mining, just like any other mining has a considerable impact on the environment and can lead to catastrophic result if preventive measures are not implemented.

Mining graphite involves the use of explosives to crack open the rock joints and to expose the graphite. The amount of explosives used in this process is often more than what actually is required and therefore ends up creating damage to unintended areas as well. this process also result in the release of dust and very fine particles of Carbon into the atmosphere causing air pollution. This can lead to the deterioration of   the health of workers and people living in the vicinity.

Mining graphite is followed by the processing at the site itself. This processing of Graphite also has a negative impact on the environment of its own. In addition to releasing a larger amount of fine graphite particles into the atmosphere the graphite powder spillages can cause soil contamination and cause harmful effects to flora and fauna.

The underground mining process has a separate set of impacts. The emptying of fissures in the rock and the separation of rock joints can cause water to seep through them and eventually lead to landslides that can destroy the whole area. Furthermore the structure of the dug mine can result in the alteration of water tables causing a heap of environmental impacts. Disturbing the natural water cycle and introducing contaminants can cause damage to both nature and humans. 

To avoid or minimize these harmful impacts, the mining will have to be done after thorough planning with thought given to the environment as well as economic benefits. After mining the land will have to restored to its previous state to bring back the balance. Care should be taken regarding the the chemicals and explosives used in the process and also the wastes generated and discharged. By adopting these practices and through implantation of concepts like cleaner production Graphite mining can be made more environmentally friendly.

Sunday, October 23, 2011

Volcanic Glass

There are three types of rocks on earth. They are IgneousSedimentary and Metamorphic rocks. Igneous rocks are formed by the solidification of magma and are further divided into two types, Namely, Plutonic rocks(Intrusive igneous rocks) and Volcanic rocks(Extrusive igneous rocks). Plutonic rocks are the rocks that are solidified inside the earth and are usually crystalline in nature due to the slow cooling process Thus they have a coarse grained crystal structure. Volcanic rocks however solidify muck quicker and therefore often show a very fine grained crystal structure. If the cooling and solidification of the volcanic rocks happen even faster it leaves no time for crystal formation. This makes the volcanic rocks amorphous and therefore have properties of a supercooled liquid. That is, These rocks have a glassy texture and are brittle like glass. They also exhibit a conchoidal fracture just like glass. One such rock is Obsidian. Obisidian looks almost artificial and has a remarkable appearance. They are sometimes used to fashion precision cutting tools such as surgical knives. Obsidian has such an appearance that it is hard to believe that it actually is a rock and that it is formed naturally.. It looks artificial. It is a remarkable product of Earth's natural geology. Here's a picture of Obsidian.

Sunday, October 16, 2011

Hard to believe..

Here's an interesting problem. Suppose you take an extremely long ribbon and wrap it tightly around the Earth-along the equator, the distance being about 40000km. Imagine that the earth is smooth and that there no space whatsoever beneath the ribbon. Now suppose you lengthen the ribbon by 1meter. This would cause the ribbon to slack and will leave a gap from the surface of the earth to the ribbon. (look at the diagram)
How big is this gap? (Indicated by the arrow on the diagram)
Any guesses?
Well its roughly 16 centimeters. This is an interesting result many people find hard to believe. But a simple calculation will show you that it's true.
Here's the math,

For the initial case ,
c=pi*d
where
c- circumference of the earth and thus the initial length of the ribbon.
d- diameter of the earth
c1=c+1
c1-new length of the ribbon(after lengthening by 1 meter)
c1=pi*(d+2*x)
x- gap between earth and the ribbon(indicated by the arrow)
therefore,
pi*d+1=pi*d+2*pi*x
x=1/2*pi=0.159m
which is approximately equal to 16 centimeters.


Environmental Engineering

Environmental Engineering was formerly known as Sanitation Engineering and was a subdivision of Civil Engineering. As many new engineering fields, it developed into main engineering stream as its demand and complexity increased. Today it is an vital and interdisciplinary field incorporating many areas such as, Chemistry, Fluid mechanics, Hydrology, Geology and Ecology. Environmental Engineering is mainly concerned with improving public health while protecting nature.
While traditional Engineering focuses on merely utilizing resources and improving living conditions of humans, environmental engineering incorporates the conservation of nature and promoting the well being of humans and other living species in the environment as well. This approach brings out sustainability and overall development.
The key areas of environmental engineering could be identified as,
1. Providing palatable and safe public water supplies in adequate amounts.
2. Control and implement procedures to minimize water soil atmospheric and noise pollution.
3. Recycling waste where possible and proper treatment and disposal of solid and liquid wastes.
4. Implementing procedures to minimize the overall footprint.
5. Incorporating cleaner production mechanisms to protect the environment and to increase sustainability and efficiency of industries.
Environmental engineering is still an emerging field in developing countries and needs to be given immediate consideration because the efficient use and management of the earth's resources will aid development and help to sustain it.

Thursday, September 22, 2011

"With great power comes great responsibility"

Says Uncle Ben to Peter Parker in "Spider Man", and is one of the most frequently quoted and well remembered sayings from a comic book. The message it conveys is very simple-(that responsibility is directly proportional to power, being strictly scientific...  :D :D) No, but the message is very easily understood and does not require paraphrasing. But take a look around the society. Most of the cases you see will not hang together with the above quote. In fact it will be pretty much the opposite- "With great power comes even greater corruption".
From the small positions right up to the highest reigns of power, the positions of power are often occupied by selfish individuals whose only responsibility seems to be filling their own pockets. These people do not understand their responsibilities or the reason they are put into that position. They just keep wasting valuable time and resources while at times not even being aware of the duties and obligations that they are expected to fulfill. That being stated, it is necessary to note that not all individuals in positions of power are like that. Although very rare, few good souls do exist. There are people who fulfill their responsibilities properly and do justice to the position they hold. But the majority outweighs the minority.
It is a well known fact that government institutions are filled with corruption. Even the Police which is supposed to maintain and promote civil order, does not function lawfully. Also the quality of service provided by the government institutions including the Police is of very poor quality. For example the police has become a body that acknowledges crime instead of being the one that prevents it. Nowadays pizza is delivered to a home faster than the Police arriving at a crime scene. Examples like the above are often found in today's society. The main reason for this is, people in positions of power failing to realize what is expected from them or simply because they ignore their responsibilities. To change this situation the entire system needs to be changed and revolutionized, and that is not going to be easy...
(image from : wikipedia.org)

Monday, August 15, 2011

XRF

This post is about X Ray Fluorescence Spectroscopy. If the Name sounds too complicating or sounds uninteresting feel free to ignore this post. Stephen Hawking says in the preface to his book-"The Universe in a Nutshell", that his publisher advised him saying that the inclusion of an equation or technical details will cut down his readership by half. So he didn't do it. But I'm going to write about X Ray Fluorescence Spectroscopy in this blog, and I don't care about the readership. Besides, at the moment I'm writing this post, I don't have any readers! I 'm writing this as a way of remembering what I learned in preparing a presentation on XRF under the module Analytical Methods.
Back to the topic. When high energy electromagnetic radiation-usually in the form of X Rays, strikes a material, The atoms in the material may get ionized. If the energy is sufficient, an atom can lose an electron from one of its lower orbitals. This causes an instability in the atom and therefore an electron from a higher orbital fills in the gap created by the dismissed electron. This causes a release of energy again in the form of X rays but with lower energy than the primary, incident X rays. These secondary X rays are called Fluorescent X rays, and the phenomenon is named Fluorescence.
This released energy corresponds to the energy difference between the orbitals involved and is unique to the atoms of a particular element. This makes it possible, to identify the elements present in a sample by analyzing its fluorescent X rays. In fact, analyzing here means measuring the energy of the emitted radiation. This method of analysis is called X Ray Fluorescence Spectroscopy.
The XRF Spectrometer consists of the primary X ray Source, the sample, the detector and the computer. XRF Spectrometers are further classified into two types;
1. Energy Dispersive Spectrometers(EDS/EDX)
2. Wavelength Dispersive Spectrometers(WDS/WDX)
In the energy Dispersive type the fluorescent X rays are directly measured and is the faster and cheaper method. The Wavelength dispersive type uses an analyzer crystal to separate the different wavelengths before they are focused into the detector. This method the more sensitive method.
A variety of elements can be identified using XRF Spectroscopy and it is commonly used in Geo Chemical investigations and mineral analysis. Recent developments to this technique and emergence of handheld XRF Spectrometers has brought about its application in fields like forensics and archaeology as well. XRF Spectroscopy was recently used to analyze the painting techniques used by Leonardo Da Vinci in creating his world famous masterpiece-"Mona Lisa".

Thursday, June 2, 2011

The Onion Earth

I knew the internal structure of the Earth and its layers- crust, mantle, outer core, and inner core since I was 9 years old. I also knew about plate tectonics and how continents change over time. But few days ago when I was thinking about the plate movements and volcanoes I came across a contradiction... If the crust lies on top of the mantle and if the upper part of the mantle is solid, how do the plates move about? where does the lava come from?
After reading about it I saw that I had not known the existence of a layer within the mantle until then..-The "Asthenosphere". Upon further reading I found that there are so many layers of the earth in addition to the above mentioned primary layers.. like an Onion.
So the Earths tectonic plates comprise of the crust and the uppermost, solid part of the mantle. This is called the "Lithosphere" below the lithosphere lies the asthenosphere which is also part of the mantle. The asthenosphere is of higher temperature and partly molten. It on this layer that the lithospheric plates lie and slowly move giving rise to the continental drift. Beneath the mantle lies the usual liquid outer core and the inner core.
Image taken from Wikipedia

 The onion like structure of the earth even extends beyond the surface of the earth into the atmosphere. The layers of the atmosphere starting from the bottommost layer are, Troposphere, Stratosphere, Mesosphere, Thermosphere and Exosphere.

Monday, May 30, 2011

Remembering Pi..

3.14159265358979..... Pi is arguably the most famous constant in mathematics. First introduced in primary school geometry, it continuously appears even in the most advanced areas of mathematics and physics. The digits of Pi are still being calculated and no pattern has been found in the occurrence of the digits.
In the past memorizing the digits of Pi has been an obsession, although today memorizing Pi would be of no use because any pocket calculator would give its value up to the 8th decimal place..Nevertheless I feel it is good to remember this important constant to at least its 6th decimal place (because we are capable of  memorizing several 10digit phone numbers! ). However, the purpose of this post is to give a an easy way of remembering the digits of Pi, which I found in a book that I read. It would be useful for those who don't want to memorize numbers..Use the sentence "How I wish I could recollect Pi" in which the number of letters in each word equals a digit, to remember Pi up to 6 decimal places. To remember up to 10 decimal places, use, "How I wish I could recollect Pi easily using one trick ". I found the above sentences in the book "Strength in Numbers" by Sherman K. Stein.

Friday, May 27, 2011

Asperger's Syndrome

 I recently read an article about Asperger's syndrome in the Sunday Times and was surprised to find that among the ones who suffered from it were people like Isaac Newton, Albert Einstein, Abraham Lincoln, Beethoven, Marilyn Monroe, Virginia Woolf and even Elvis Presley! Among the notable people affected by this syndrome in the present are Tom Hanks, Robin Williams and Bill Gates. Clearly this is a very interesting.. It seems that Aspergers Syndrome somehow helps a person to achieve brilliance in his/her field.

The article went on to say that Asperger's Syndrome is not a disease, but a "set of behavioural traits". It had also listed some of the traits that can be identified in children as follows,
  • Reluctance to look at the face of the other person when having a conversation.
  • Not discussing what happens in school with the parents.
  • Abhorrence of a change in routine – if it happens, throwing huge tantrums.
  • In-depth study and focus on a subject he likes and speaking avidly on it.
  • Cannot comprehend jokes. If someone jokes with him he will misunderstand it and think ill of the other person and walk off.
  • Acting and talking in a mature manner, not in keeping with his age.
  • Preference for the company of older people than his peers.
  • Unresponsive to others’ feelings.
  • Living in a world of his own.
  • Preference for solitude.
  • Having unusual ideas and views which result in others teasing him. As others don’t agree with his views, huge friction occurs. He will also try to impose his will on others, against the wishes of the majority and fight tooth and nail which will cause rows both in the classroom and the playground.
  • He will lose his temper frequently and be unable to control it along with being intolerant of others’ view.
  • He will be very selective of the food he eats or the clothes he wears, rejecting all else except his preferences.
  • He will be fearful of unusual things.
  • Intolerant of delay, he will want everything done immediately.
  • He has only a chosen few he calls friends.
 -Extracted from The Sunday Times Mediscene May 15 2011-

In my opinion, many of us have at least some of these traits..It is a part of what makes us unique as individuals. Try imagining a person without any of these traits. It would be a person with no specific ideas or preferences, with no ability to focus his attention on something and with low self esteem... So it seems that it is better to have Asperger's syndrome rather than being a workaday person without it  ;)

Monday, April 4, 2011

The "Face" on Mars

In 1976 when the spacecraft Viking1 was orbiting the planet Mars taking photographs of its surface, one photograph caught the attention of many. It showed a formation on the surface of the planet looking strikingly like a human face.
                              (Image from:Wikipedia, the free encyclopedia)
Astronomers at NASA immediately wrote it off saying it was an illusion created by lighting, however upon further examination it was found that the actual 3 dimensional structure itself resembles a human face; i.e its not merely an illusion.

This "face" created a lot of excitement during that time and theories that include extra terrestrial intelligence or lost alien civilizations were put forward to explain it.

Although a slight air of mystery still surrounds this face of mars, It is now widely accepted that the "face" is a natural formation. It seems very rare and highly improbable but, such natural formations have occurred on earth too.  The old man of the mountain, the Badlands Guardian are two such examples.

In my opinion the face of Mars has something to do with our perception too. We see a face because we expect to see a face, and because our brains are very good at identifying faces. Many ancient cultures have seen a face, a rabbit, or something else on the moon. Our ancestors saw so many images and patterns among the stars. Our minds always look for patterns in things and succeed in finding them. It has been proven mathematically that any large collection of objects has patterns concealed in it, therefore it follows that we can identify patterns in practically anything. It is because of this that we associate a face or something else with natural formations and heavenly objects.

"It is likely that our very existence as a species owes much to this ability to delineate patterns. Evolution may have made us a little too adept at spotting them. Our propensity to see patterns where none exists at all is witnessed by ancient Man's enthusiastic identification of ploughs and hunters, crabs and scales tracing out patterns of stars we call the constellations, or by modern Man's enthusiasm for Martian Canals." 
- The World Within the World-John D. Barrow (Oxford,1990)   

Sri Lanka's loss at the CWC Final

Thousands of hopes were shattered when Sri Lanka lost the final match of the ICC Cricket world Cup for the second consecutive time. However more than the loss, it was the poor quality of cricket played, and the lack of enthusiasm shown by some of the players in the team that disturbed many viewers.

To begin with, the changes and replacements made in the playing squad just for the final match were surprising..Why make drastic changes to a team that has already performed very well? also, leaving out the bowler with the best record for the team in the tournament, and bringing in cricketers who haven't played a single match in tournament to play the final was puzzling.

Changes and replacements kept aside, the performance in the field was also of very poor standards. Dropping important catches and misfieldings were increasingly common. There was a sharp contrast between the Indian and the Sri Lankan teams in terms of fielding.. While the Indians were diving across the ground to save runs, Some of our fielders just lazily bent over while the ball went passing them.

However only some of the players lacked the enthusiasm. Some others showed great commitment and sportsmanship specially when batting. This was a match we could have won. This is why the ardent fans of Sri Lanka Cricket are upset... Anyway what's done is done and hopefully our cricketers will learn from the mistakes made this time and gear up for winning the next world cup.

Sunday, March 27, 2011

Sky Observation at the Arthur C. Clarke Institute

After the first semester examination in our University, We were supposed to study 3 non technical modules-two of  which were compulsory and one of our own choice. The module I chose was Astronomy. The reasons for my choice were the interest I had in Astronomy, The interesting course contents and most importantly, The observation sessions.

We had two observation sessions at the Arthur C. Clarke Institute. One in the night for the observation of the Moon and the Planets and one session in the morning for observation of the Sun.
The telescope at the Arthur C. Clarke Institute, is the largest telescope in Sri Lanka. It is a Cassegrain Reflector type telescope and has a primary mirror of diameter 45cm. It uses an Equatorial Mount and is moved using computer controlled servo motors. It uses CCD cameras as the main imaging device.







It was unfortunate that the on the night we had our moon observation, the sky was very cloudy and not a single star could be seen. Also it was lightning. Because of this we couldn't use the Cassegrain reflector that night. Instead we used a much smaller reflector to look at the moon. The image of the moon was not clear due to the obstructing clouds.

The following day was better. We viewed the sun through the filtered Cassegrain telescope and saw two Sunspots. We also saw the Chromosphere of the Sun through an H-alpha filter.



The two sessions at the institute were very interesting and educational. It was a truly memorable experience.

Sunday, March 13, 2011

Engineering with Responsibility

The crisis the Earth faces today is not a secret, almost everyone knows about it but very few take it seriously. Chances are that someone reading this post might also disregard this by saying "just another global warming message....".

However, the problems we face today are not limited to global warming... Pollution is at an all time high, Several species have become extinct or are in the brink of extinction, Natural disasters are becoming increasingly common, the list goes on... Clearly there is something wrong, and we humans are responsible.

Our actions, especially engineering ones have disturbed the "balance" in nature causing ecosystems to fall apart and create catastrophe in the process. All disasters we face today are either caused by us, or its destructive effects are magnified by our actions. For example, Sea erosions and tsunamis hit us harder because we excavate and remove all the natural coral reefs in the coastal area which would otherwise serve as a very effective natural wave breaker. Also filling of marsh land increases the likelihood and severity of floods.

But some people justify these actions by saying that it is necessary for development and improvement of our lifestyle... or these are minor side effects of engineering a better world. All these claims are false. How can we say we are developed when we face natural disasters almost everyday? Engineering that does not go hand in hand with nature is not engineering but "Reckless building".

Engineering encompasses the ideas of creating with care and concern for the surroundings, managing resources efficiently, and ensuring sustainability. Engineering which neglects the above aspects cannot simply be called Engineering. Fortunately, as of recently more attention has been given to this area resulting in looking for ways to protect nature and the environment. Emergence of new fields of Engineering such as Environmental Engineering and Earth Resources Engineering is a promising trend.

It is very important that we take the task of protecting our earth very seriously. Engineers need to work with responsibility. The only way of improving ourselves is by protecting nature and using its resources carefully and efficiently.

What we should understand is that all the resources on earth are limited. Therefore we must use them with extreme care. After all, Earth is all we have got, We don't have another planet to go to...
see what I mean: http://www.oneearth.org/