The Engineers of 21st Century

Areas and perimeters of different shapes

2010-05-28T09:37:00.000-07:00

Area of a Square

If l is the side-length of a square, the area of the square is l2 or l × l.

Example:

What is the area of a square having side-length 3.4?

The area is the square of the side-length, which is 3.4 × 3.4 = 11.56.

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Area of a Rectangle

The area of a rectangle is the product of its width and length.

Example:

What is the area of a rectangle having a length of 6 and a width of 2.2?

The area is the product of these two side-lengths, which is 6 × 2.2 = 13.2.

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Area of a Parallelogram

The area of a parallelogram is b × h, where b is the length of the base of the parallelogram, and h is the corresponding height. To picture this, consider the parallelogram below:

We can picture "cutting off" a triangle from one side and "pasting" it onto the other side to form a rectangle with side-lengths b and h. This rectangle has area b × h.

Example:

What is the area of a parallelogram having a base of 20 and a corresponding height of 7?

The area is the product of a base and its corresponding height, which is 20 × 7 = 140.

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Area of a Trapezoid

If a and b are the lengths of the two parallel bases of a trapezoid, and h is its height, the area of the trapezoid is

1/2 × h × (a + b) .

To picture this, consider two identical trapezoids, and "turn" one around and "paste" it to the other along one side as pictured below:

The figure formed is a parallelogram having an area of h × (a + b), which is twice the area of one of the trapezoids.

Example:

What is the area of a trapezoid having bases 12 and 8 and a height of 5?

Using the formula for the area of a trapezoid, we see that the area is

1/2 × 5 × (12 + 8) = 1/2 × 5 × 20 = 1/2 × 100 = 50.

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Area of a Triangle

Consider a triangle with base length b and height h.

The area of the triangle is 1/2 × b × h.

To picture this, we could take a second triangle identical to the first, then rotate it and "paste" it to the first triangle as pictured below:

The figure formed is a parallelogram with base length b and height h, and has area b × ×h.

This area is twice that of the triangle, so the triangle has area 1/2 × b × h.

Example:

What is the area of the triangle below having a base of length 5.2 and a height of 4.2?

The area of a triangle is half the product of its base and height, which is 1/2 ×5.2 × 4.2 = 2.6 × 4.2 = 10.92..

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Area of a Circle

The area of a circle is Pi × r2 or Pi × r × r, where r is the length of its radius. Pi is a number that is approximately 3.14159.

Example:

What is the area of a circle having a radius of 4.2 cm, to the nearest tenth of a square cm? Using an approximation of 3.14159 for Pi, and the fact that the area of a circle is Pi × r2, the area of this circle is Pi × 4.22 3.14159 × 4.22 =55.41…square cm, which is 55.4 square cm when rounded to the nearest tenth.

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Perimeter

The perimeter of a polygon is the sum of the lengths of all its sides.

Example:

What is the perimeter of a rectangle having side-lengths of 3.4 cm and 8.2 cm? Since a rectangle has 4 sides, and the opposite sides of a rectangle have the same length, a rectangle has 2 sides of length 3.4 cm, and 2 sides of length 8.2 cm. The sum of the lengths of all the sides of the rectangle is 3.4 + 3.4 + 8.2 + 8.2 = 23.2 cm.

Example:

What is the perimeter of a square having side-length 74 cm? Since a square has 4 sides of equal length, the perimeter of the square is 74 + 74 + 74 + 74 = 4 × 74 = 296.

Example:

What is the perimeter of a regular hexagon having side-length 2.5 m? A hexagon is a figure having 6 sides, and since this is a regular hexagon, each side has the same length, so the perimeter of the hexagon is 2.5 + 2.5 + 2.5 + 2.5 + 2.5 + 2.5 = 6 × 2.5 = 15m.

Example:

What is the perimeter of a trapezoid having side-lengths 10 cm, 7 cm, 6 cm, and 7 cm? The perimeter is the sum 10 + 7 + 6 + 7 = 30cm.

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Circumference of a Circle

The distance around a circle. It is equal to Pi ( ) times the diameter of the circle. Pi or is a number that is approximately 3.14159.

Example:

What is the circumference of a circle having a diameter of 7.9 cm, to the nearest tenth of a cm? Using an approximation of 3.14159 for , and the fact that the circumference of a circle is times the diameter of the circle, the circumference of the circle is Pi × 7.9 3.14159 × 7.9 = 24.81…cm, which equals 24.8 cm when rounded to the nearest tenth of a cm.

Cupola furnace

2010-01-10T09:44:00.000-08:00

Cupola Furnace

A Cupola or Cupola furnace is a melting device used in foundries that can be used to melt cast iron, ni-resist iron and some bronzes. The cupola can be made almost any practical size. The size of a cupola is expressed in diameters and can range from 18 inches to 13 feet^[1]. The overall shape is cylindrical and the equipment is arranged vertically, usually supported by four legs. The overall look is similar to a large smokestack.

A cupola furnace in operation at Wayne State University, in Detroit, Michigan

The bottom of the cylinder is fitted with doors which swing down and out to 'drop bottom'. The top where gases escape can be open or fitted with a cap to prevent rain from entering the cupola. To control emissions a cupola may be fitted with a cap that is designed to pull the gases into a device to cool the gasses and remove particulate matter.
The shell of the cupola, being usually made of steel, has refractory brick and refractory patching material lining it. The bottom is lining in a similar manner but often a clay and sand mixture may be used, as this lining is temporary. The bottom lining is compressed or 'rammed' against the bottom doors. Some cupolas are fitted with cooling jackets to keep the sides cool and with oxygen injection to make the coke fire burn hotter.

Microsoft AccessProfessional2007

2009-12-23T07:29:00.000-08:00

Microsoft Access Professional 2007

A complete Tutorial Guide

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DJVU Download

2009-12-23T07:10:00.000-08:00

DJVU Downlod

Note:Necessary for M/C Design by Norton

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Anti-Lock Brake System

2009-12-22T10:35:00.000-08:00

Anti-Lock Brake System

Anti Lock Brakes System

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Solutoin manual of Shigley 8th Edition

2009-12-20T19:59:00.000-08:00

Solutoin manual of Shigley 8th

Edition

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Machine Design by Robert L. Norton

2009-12-20T19:46:00.000-08:00

Machine Design by Robert L. Norton

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Shigley’s Mechanical Engineering Design

2009-12-20T17:41:00.001-08:00

Shigley’s Mechanical

Engineering Design

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Academic Ranking of World Universities in Engineering/Technology and Computer Sciences - 2009

2009-12-18T03:29:00.001-08:00

Academic Ranking of World Universities in Engineering/Technology and Computer Sciences - 2009

World Rank	Institution*	Country	Score on HiCi	Score on PUB	Score on TOP	Score on Fund	Total Score
1	Massachusetts Institute of Technology (MIT)		99	78	94	98	100
2	Stanford University		100	65	97	79	92.5
3	University of Illinois at Urbana-Champaign		63	73	89	91	85.8
4	University of California, Berkeley		77	71	90	70	83.6
5	Carnegie Mellon University		53	55	90	100	81.1
6	University of Michigan - Ann Arbor		61	69	90	77	81.0
7	The University of Texas at Austin		73	63	86	71	79.8
8	Georgia Institute of Technology		35	81	86	91	79.7
9	University of California, San Diego		68	58	90	75	78.9
10	Pennsylvania State University - University Park		69	68	84	70	78.8
11	University of Southern California		60	51	91	83	77.4
12	California Institute of Technology		73	53	97	57	75.9
13	University of California, Santa Barbara		80	48	100	50	75.6
14	University of Maryland, College Park		56	60	82	79	75.3
15	Swiss Federal Institute of Technology of Lausanne		55	62	87		73.8
15	University of Cambridge		55	63	86		73.8
17	Purdue University - West Lafayette		51	69	81	71	73.7
18	Cornell University		56	50	93	70	73.3
19	University of Toronto		61	65	84	51	71.2
20	Tohoku University		47	85	64		70.7
21	National University of Singapore		20	85	89		70.4
22	Northwestern University		66	52	93	48	70.2
22	The Ohio State University - Columbus		49	58	86	67	70.2
24	University of Florida		43	60	88	66	69.8
25	University of Wisconsin - Madison		49	56	83	67	69.1
26	Kyoto University		35	76	80		69.0
26	Princeton University		69	46	93	46	69.0
26	University of California, Los Angeles		45	55	94	60	69.0
26	University of Washington		53	52	88	61	69.0
30	The Imperial College of Science, Technology and Medicine		40	68	82		68.7
31	Texas A&M University - College Station		20	67	76	90	68.6
32	The University of Manchester		45	64	79		68.0
33	Tokyo Institute of Technology		40	73	74		67.9
34	North Carolina State University - Raleigh		51	55	79	65	67.8
35	University of Minnesota, Twin Cities		51	54	90	54	67.4
36	The Hong Kong University of Science and Technology		35	57	91		66.3
37	National Cheng Kung University		14	82	84		65.3
38	Harvard University		55	47	99	38	64.9
38	University of Pennsylvania		49	41	97	51	64.9
40	Technion-Israel Institute of Technology		35	58	85		64.4
41	Swiss Federal Institute of Technology Zurich		20	66	91		63.9
42	University of California, Irvine		49	44	89	52	63.6
43	Virginia Polytechnic Institute and State University		35	59	79	60	63.3
44	Tsinghua University		0	100	75		63.2
45	National Chiao Tung University		20	68	86		63.0
46	University of Oxford		40	50	83		62.8
47	University of California, Davis		40	54	87	50	62.7
48	Rutgers, The State University of New Jersey - New Brunswick		47	42	84		62.4
49	McGill University		37	53	81		61.9
50	University of Massachusetts Amherst		56	39	93	40	61.8
51-77	Arizona State University - Tempe		28	50	87	45
51-77	Catholic University of Leuven		20	56	85
51-77	Chalmers University of Technology		28	49	82
51-77	City University of Hong Kong		20	65	82
51-77	Columbia University		35	46	86
51-77	Duke University		42	38	89	48
51-77	Indian Institute of Science		28	51	79
51-77	Indian Institute of Technology Kharagpur		28	60	69
51-77	National Taiwan University		0	77	88
51-77	Osaka University		28	71	70
51-77	Pierre and Marie Curie University - Paris 6		20	52	88
51-77	Polytechnic University of Turin		35	52	80
51-77	Rensselaer Polytechnic Institute		35	45	85	46
51-77	Seoul National University		0	80	77
51-77	Shanghai Jiao Tong University		0	93	66
51-77	Technical University of Denmark		20	53	88
51-77	The Chinese University of Hong Kong		28	46	87
51-77	The University of Sheffield		28	53	81
51-77	University of British Columbia		20	59	84
51-77	University of Colorado at Boulder		40	44	95	48
51-77	University of Melbourne		28	45	88
51-77	University of New South Wales		20	54	86
51-77	University of Science and Technology of China		20	61	85
51-77	University of Sydney		28	51	88
51-77	University of Virginia		41	38	85	47
51-77	University of Waterloo		35	62	81	32
51-77	Zhejiang University		0	87	75
78-100	Catholic University of Louvain		20	39	92
78-100	Delft University of Technology		0	68	83
78-100	Korea Advanced Institute of Science and Technology		0	70	82
78-100	Lund University		24	41	91
78-100	Michigan State University		40	45	83	33
78-100	Nanyang Technological University		0	77	79
78-100	National Tsing Hua University		0	61	90
78-100	Pohang University of Science and Technology		20	49	85
78-100	Rice University		40	35	92	37
78-100	Technical University Munich		28	44	79
78-100	Tel Aviv University		26	43	87
78-100	The Hebrew University of Jerusalem		35	30	91
78-100	The University of Tokyo		0	79	74
78-100	University of Alberta		28	58	76	39
78-100	University of Bordeaux 1		35	37	83
78-100	University of Bristol		28	41	83
78-100	University of Delaware		28	40	92	40
78-100	University of Leeds		20	47	83
78-100	University of Southampton		28	51	75
78-100	University of Twente		20	43	92
78-100	University of Utah		28	41	91	42
78-100	Uppsala University		28	39	85
78-100	Utrecht University		35	30	90
* Institutions within the same rank range are listed alphabetically.

Wear of metals

2009-12-14T04:33:00.000-08:00

Phenomenon of wear in Metals

Wear of Metals

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Solar Thermal Systems

2009-11-24T23:03:00.000-08:00

Solar Thermal Systems

Parabolic troughs, like these used in Colorado, concentrate the sun's energy to great temperatures.There are two types of solar thermal systems: passive and active. A passive system requires no equipment, like when heat builds up inside your car when it's left parked in the sun. An active system requires some way to absorb and collect solar radiation and then store it.

Solar thermal power plants are active systems, and while there are a few types, there are a few basic similarities: Mirrors reflect and concentrate sunlight, and receivers collect that solar energy and convert it into heat energy. A generator can then be used to produce electricity from this heat energy.

The most common type of solar thermal power plants, including those plants in California's Mojave Desert, use a parabolic trough design to collect the sun's radiation. These collectors are known as linear concentrator systems, and the largest are able to generate 80 megawatts of electricity [source: U.S. Department of Energy]. They are shaped like a half-pipe you'd see used for snowboarding or skateboarding, and have linear, parabolic-shaped reflectors covered with more than 900,000 mirrors that are north-south aligned and able to pivot to follow the sun as it moves east to west during the day. Because of its shape, this type of plant can reach operating temperatures of about 750 degrees F (400 degrees C), concentrating the sun's rays at 30 to 100 times their normal intensity onto heat-transfer-fluid or water/steam filled pipes [source: Energy Information Administration]. The hot fluid is used to produce steam, and the steam then spins a turbine that powers a generator to make electricity.

While parabolic trough designs can run at full power as solar energy plants, they're more often used as a solar and fossil fuel hybrid, adding fossil fuel capability as backup.

Solar power tower systems are another type of solar thermal system. Power towers rely on thousands of heliostats, which are large, flat sun-tracking mirrors, to focus and concentrate the sun's radiation onto a single tower-mounted receiver. Like parabolic troughs, heat-transfer fluid or water/steam is heated in the receiver (power towers, though, are able to concentrate the sun's energy as much as 1,500 times), eventually converted to steam and used to produce electricity with a turbine and generator.

Power tower designs are still in development but could one day be realized as grid-connected power plants producing about 200 megawatts of electricity per tower.

A third system is the solar dish/engine. Compared to the parabolic trough and power towers, dish systems are small producers (about 3 to 25 kilowatts). There are two main components: the solar concentrator (the dish) and the power conversion unit (the engine/generator). The dish is pointed at and tracks the sun and collects solar energy; it's able to concentrate that energy by about 2,000 times. A thermal receiver, a series of tubes filled with a cooling fluid (such as hydrogen or helium), sits between the dish and the engine. It absorbs the concentrated solar energy from the dish, converts it to heat and sends that heat to the engine where it becomes electricity.

Introduction to Solar Thermal Systems

2009-11-24T23:02:00.000-08:00

Introduction to Solar Thermal Systems

Most of us don't think much about where our electricity comes from, only that it's available and plentiful. Electricity generated by burning fossil fuels such as coal, oil and natural gas, emits carbon dioxide, nitrogen oxides and sulfur oxides -- gases scientists believe contribute to climate change. Solar thermal (heat) energy is a carbon-free, renewable alternative to the power we generate with fossil fuels like coal and gas. This isn't a thing of the future, either. Between 1984 and 1991, the United States built nine such plants in California's Mojave Desert, and today they continue to provide a combined capacity of 354 megawatts annually, power used in 500,000 Californian homes [source: Hutchinson]. Reliable power, at that. In 2008 when six days of peak demand buckled the power grid and brought electricity outages in California, those solar thermal plants continued to produce at 110 percent capacity [source: Kanellos].

Wondering where the technology's been since then? In the 1990s when prices of natural gas dropped, so did interest in solar thermal power. Today, though, the technology is poised for a comeback. It's estimated by the U.S. National Renewable Energy Laboratories that solar thermal power could provide hundreds of gigawatts of electricity, equal to more than 10 percent of demand in the United States [source: LaMonica].

Shake the image of solar panels from your head -- that kind of demand is going to require power plants. There are two main ways of generating energy from the sun. Photovoltaic (PV) and concentrating solar thermal (CST), also known as concentrating solar power (CSP) technologies.

PV converts sunlight directly into electricity. These solar cells are usually found powering devices such as watches, sunglasses and backpacks, as well as providing power in remote areas.

Solar thermal technology is large-scale by comparison. One big difference from PV is that solar thermal power plants generate electricity indirectly. Heat from the sun's rays is collected and used to heat a fluid. The steam produced from the heated fluid powers a generator that produces electricity. It's similar to the way fossil fuel-burning power plants work except the steam is produced by the collected heat rather than from the combustion of fossil fuels.

This is Mechanical Engineering

2009-11-18T09:35:00.001-08:00

Mohr's Circle

2009-11-17T03:20:00.001-08:00

Mohr's Circle

Introduced by Otto Mohr in 1882, Mohr's Circle illustrates principal stresses and stress transformations via a graphical format,

The two principal stresses are shown in red, and the maximum shear stress is shown in orange. Recall that the normal stresses equal the principal stresses when the stress element is aligned with the principal directions, and the shear stress equals the maximum shear stress when the stress element is rotated 45° away from the principal directions.

As the stress element is rotated away from the principal (or maximum shear) directions, the normal and shear stress components will always lie on Mohr's Circle.

Mohr's Circle was the leading tool used to visualize relationships between normal and shear stresses, and to estimate the maximum stresses, before hand-held calculators became popular. Even today, Mohr's Circle is still widely used by engineers all over the world.

Derivation of Mohr's Circle:

To establish Mohr's Circle, we first recall the stress transformation formulas for plane stress at a given location,

Using a basic trigonometric relation (cos²2q + sin²2q = 1) to combine the two above equations we have,

This is the equation of a circle, plotted on a graph where the abscissa is the normal stress and the ordinate is the shear stress. This is easier to see if we interpret s_x and s_y as being the two principal stresses, and t_xy as being the maximum shear stress. Then we can define the average stress, s_avg, and a "radius" R (which is just equal to the maximum shear stress),

The circle equation above now takes on a more familiar form,

The circle is centered at the average stress value, and has a radius R equal to the maximum shear stress, as shown in the figure below,

Working of a Rotary Engine

2009-11-17T02:49:00.000-08:00

Working of a Rotary Engine

A rotary engine is an internal combustion engine, like the engine in your car,but it works in a completely different way than the conventional piston engine.In a piston engine, the same volume of space (the cylinder) alternately does four different jobs -- intake, compression, combustion and exhaust. A rotary engine does these same four jobs, but each one happens in its own part of the housing. It's kind of like having a dedicated cylinder for each of the four jobs, with the piston moving continually from one to the next.
The rotary engine (originally conceived and developed by Dr. Felix Wankel) is sometimes called a Wankel engine, or Wankel rotary engine.

Principles of a Rotary Engine

Like a piston engine, the rotary engine uses the pressure created when a combination of air and fuel is burned. In a piston engine, that pressure is contained in the cylinders and forces pistons to move back and forth. The connecting rods and crankshaft convert the reciprocating motion of the pistons into rotational motion that can be used to power a car.
In a rotary engine, the pressure of combustion is contained in a chamber formed by part of the housing and sealed in by one face of the triangular rotor, which is what the engine uses instead of pistons.

The rotor and housing of a rotary engine from a Mazda RX-7: These parts replace the pistons, cylinders, valves, connecting rods and camshafts found in piston engines.

The rotor follows a path that looks like something you'd create with a Spirograph. This path keeps each of the three peaks of the rotor in contact with the housing, creating three separate volumes of gas. As the rotor moves around the chamber, each of the three volumes of gas alternately expands and contracts. It is this expansion and contraction that draws air and fuel into the engine, compresses it and makes useful power as the gases expand, and then expels the exhaust.

We'll be taking a look inside a rotary engine to check out the parts, but first let's take a look at a new model car with an all-new rotary engine.

Mazda RX-8
Mazda has been a pioneer in developing production cars that use rotary engines. The RX-7, which went on sale in 1978, was probably the most successful rotary-engine-powered car. But it was preceded by a series of rotary-engine cars, trucks and even buses, starting with the 1967 Cosmo Sport. The last year the RX-7 was sold in the United States was 1995, but the rotary engine is set to make a comeback in the near future.

The Mazda RX-8 , a new car from Mazda, has a new, award winning rotary engine called the RENESIS. Named International Engine of the Year 2003, this naturally aspirated two-rotor engine will produce about 250 horsepower. For more information, visit Mazda's RX-8 Web site.

Disadvantages of the Two-stroke

2009-11-17T02:42:00.000-08:00

Disadvantages of the Two-stroke

You can now see that two-stroke engines have two important advantages over four-stroke engines: They are simpler and lighter, and they produce about twice as much power. So why do cars and trucks use four-stroke engines? There are four main reasons:

Two-stroke engines don't last nearly as long as four-stroke engines. The lack of a dedicated lubrication system means that the parts of a two-stroke engine wear a lot faster.
Two-stroke oil is expensive, and you need about 4 ounces of it per gallon of gas. You would burn about a gallon of oil every 1,000 miles if you used a two-stroke engine in a car.
Two-stroke engines do not use fuel efficiently, so you would get fewer miles per gallon.
Two-stroke engines produce a lot of pollution -- so much, in fact, that it is likely that you won't see them around too much longer. The pollution comes from two sources. The first is the combustion of the oil. The oil makes all two-stroke engines smoky to some extent, and a badly worn two-stroke engine can emit huge clouds of oily smoke. The second reason is less obvious but can be seen in the following figure:

Each time a new charge of air/fuel is loaded into the combustion chamber, part of it leaks out through the exhaust port. That's why you see a sheen of oil around any two-stroke boat motor. The leaking hydrocarbons from the fresh fuel combined with the leaking oil is a real mess for the environment.
These disadvantages mean that two-stroke engines are used only in applications where the motor is not used very often and a fantastic power-to-weight ratio is important.

Pipe Line Design Handbook

2009-11-17T02:34:00.000-08:00

Pipe Line Design Handbook

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Note:This link is not of book shown This image is added just for the effect.

Top 5 Scary Technologies of 2008

2009-11-16T08:13:00.000-08:00

1.Hubble Space Telescope:

Technology makes our lives better. You're enjoying your new high-definition television, and have your work and personal appointments organized on your computer. You pay your bills electronically and save time and money. That's fine and dandy, until someone takes out the electronic banking system and the machines take over the planet.

Sounds crazy? Perhaps. None of the technologies we included in our top 5 are likely to rain death and destruction on our little planet, though that doesn't prevent people from being unnerved by them. Read on to find out what weirdness may await in 2009 -- and beyond.

2.Hearing Voices at the Store:

This may not sound so scary, and once you know what's going on, it isn't. But it might be a little unsettling to be walking in a store and hearing voices asking you to buy things. If you look around, you won't see anyone speaking, and none of the other shoppers will seem alarmed -- no one else can hear it but you.

A company called Holosonics developed the Audio Spotlight system, which uses tiny speakers to focus sound into a very narrow beam. Ultrasonic frequencies are too high for the human ear to hear, but as the sound travels from the Audio Spotlight system's speakers, air distorts the sound and makes it audible. It's perfect for in-store advertising, but you'd have to be standing in the right place to hear it. You can learn more about it if you read, Can companies beam advertisements into my brain?

Perhaps hearing voices isn't frightening, but what about having your computer taken away? Keep reading to learn more.

3.Law Enforcement Takes Your Laptop:

If you travel with your laptop or BlackBerry, listen up. According to the 9th Circuit Court, it is perfectly legal for Federal Customs and Border Patrol agents to seize your technological devices when you enter the United States. You might not have anything illegal on your computer's hard drive, but even if you're just carrying your personal computer and you have all your kids' vacation pictures on there, there's no telling when -- or if -- you'll get your machine back.

The idea is that in the interest of national security, U.S. officials have the right to confiscate electronics to search them for evidence of a crime -- even without probable cause. If that sounds scary to you, you can read more in our article, Can the government take away my laptop?

Perhaps the government can use this decision to prevent an attack, but can anyone prevent an all-out cyber war? On the next page, we'll take a look.

4.Cyber War:

Imagine a war fought completely by computer. No, we're not talking about a scene out of the movie WarGames, we're talking an all-out attack on a nation's electronic infrastructure. What's that, you may ask? Those are the systems that control emergency response services, banks and other electronic commerce, the systems that run the electrical grid, water and fuel pipeline controls, communications networks, and oh, yeah: defense weaponry. A well-executed attack could cause serious disruption and open the populace up to physical threats.

Attacks like these have already been launched against some countries. Russians attacked Georgia with denial-of-service attacks. Hackers have taken on the Pentagon, and some suspect terrorist organizations of training their operatives to launch computer assaults. So how do you defend against a cyber attack? Educating people about computer viruses and Trojan horses will help, and using updated antivirus software is also important. You can find out more by reading Is cyber war coming?

Cyber attacks might actually be useful tools against machines who have learned to think for themselves and chosen to eliminate humanity. It's the stuff of science fiction, but why do some people believe this could happen?

5.The Technological Singularity:

Artificial intelligence (AI) has come a long way since computers first made the scene. Yet we're not at the edge of a dystopian society in which the machines run amok and humankind fights for its survival. At least, not yet.

Vernor Vinge, a math professor at San Diego State University, proposed what he calls the singularity -- a time at which computer networks may become self-aware through advanced AI, and interfaces between people and computers help humankind evolve. Biological advancements may become so sophisticated that doctors can even engineer human intelligence. There is a possibility, however, that AI might allow machines to take over the world. There's no guarantee that such a scenario will really happen, and technological limitations may prevent it. Still, the idea that machines might someday decide we're irrelevant and arrange for our destruction is more than a little creepy. You can read more when you take a look at What's the technological singularity?

In 2008 scientists completed a gigantic machine that they believe will help solve some of the secrets of the universe. Some critics of the project were so afraid of it that they filed a lawsuit to prevent it from being turned on. Why? Find out on the next page.

4 High-Tech Surprises From the USS New York

2009-11-16T03:26:00.001-08:00

The USS New York, commissioned this month in its namesake city, is the Navy's newest warship. It's a Landing Platform Dock ship, which means it brings Marines to wherever they are needed. The 700 marines on the ship travel ready for combat, and that means landing hovercraft (called Landing Craft Air Cushions), attack helicopters, tanks, amphibious vehicles and V-22 Ospreys come along for the ride. The aircraft launch from the ship and are maintained in hangars on and below the flight deck. The New York has the most famous hull in the world—the Navy integrated 7.5 tons of steel from the fallen World Trade Center towers into the bow. But that is not the only interesting detail of this new vessel's design. Here are four high-tech surprises the USS New York has in store for enemies

USS New York makes her way up the Hudson River.

1) Invisible Invasions:

The New York's eye-catching shape, with two smooth cone shapes jutting from the deck, attracted thousands of gawkers as it moored on the west side of Manhattan. However, this shape is meant to allow the ship to remain undetected by enemy radar. Every surface on the ship's outside decks is faceted at 10 degree angles to prevent radar waves from bouncing back and returning a clean signal. All these surfaces are also painted with radar-reflective material. The duel masts are enclosed in a composite material that allows antennas to transmissions to travel through. Radar, satellite and radio hardware are housed in globes of the material. "We saw what the ship looks like in an enemy ship's radar," says Bosun Mate First Class Alan Davenport. "This big ship looks like a sailboat in the water."

2) Stealth Crane:

The Navy's desire to move toward a hostile coastline without attracting attention depends on an attention to details. The best example of this is the knuckle boom crane that the crew use to hoist boats into and out of the water, or to move cargo to and from the ship. The 22,000-pound crane is housed inside a paneled structure made of the same radar-foiling material as the hull and masts. A door underneath the arm swings open to deploy the crane, and whatever is being lifted is set down into the "boat valley," a wide space between the two masts. From there the cargo can be conveyed into the ship; if it's a vehicle, it can drive down ramps to anywhere it needs to go, including to the lowest decks where the landing craft launch. This removes any need for other heavy-duty cranes on the ship.

3) Smart Layout:

Smart ways to move cargo and ground vehicles around the ship are just the start of a smarter layout. The passageways are wide, almost spacious in some places, to keep any equipment mounted in the hallway from jutting out too far and snagging quick-moving Marines or sailors as they pass by. The passageways—or as sailors say, "p-ways"—are designed in more straight lines and take into account who is using them. For example, the ladders between Marines' berths and their landing craft or flight deck are wider than any others on board, in deference to the Marines' large backpacks. The chow hall is larger, and nearly every panel has a touch screen. "This is a big upgrade," says Davenport, who has spent 16 years in the Navy and served on other LPD ships. "The best part about being on a new ship is that all the equipment inside is also new."

4) Decoys:

The ship travels with escorts but can still take pretty good care of herself with a 30-mm cannon, Sea Sparrow missiles and myriad mounts for .50-cal. machine guns. But the New York also has decoys. If an antiship missile is inbound, a protective system (shown above) fires slivers of metal, like aluminum foil, to spoof the warhead's tracking sensors. Another neat trick to trip up torpedoes: Drag a 700-foot length of steel cord with a beacon at the tip. This towed decoy, called a Nixie, makes the ship look twice as long as it is, which ruins a torpedo's aim because the sensors in the weapon's nose aim for the middle of the target vessel.

Top 500 Universities of The World

2009-11-07T10:50:00.000-08:00

World Rank Institution* Country Total Score

1 Harvard University USA 100.0

2 Stanford University USA 77.2

3 University Cambridge UK 76.2

4 University California - Berkeley USA 74.2

5 Massachusetts Inst Tech (MIT) USA 72.4

6 California Inst Tech USA 69.0

7 Princeton University USA 63.6

8 University Oxford UK 61.4

9 Columbia University USA 61.2

10 University Chicago USA 60.5

11 Yale University USA 58.6

12 Cornell University USA 55.5

13 University California - San Diego USA 53.8

14 Tokyo University Japan 51.9

15 University Pennsylvania USA 51.8

16 University California - Los Angeles USA 51.6

17 University California - San Francisco USA 50.8

18 University Wisconsin - Madison USA 50.0

19 University Michigan - Ann Arbor USA 49.3

20 University Washington - Seattle USA 49.1

21 Kyoto University Japan 48.3

22 Johns Hopkins University USA 47.5

23 Imperial Coll London UK 46.4

24 University Toronto Canada 44.6

25 University Coll London UK 44.3

25 University Illinois - Urbana Champaign USA 43.3

27 Swiss Fed Inst Tech - Zurich Switzerland 43.2

28 Washington University - St. Louis USA 43.1

29 Rockefeller University USA 40.2

30 Northwestern University USA 39.5

31 Duke University USA 38.9

32 New York University USA 38.7

33 University Minnesota - Twin Cities USA 38.3

34 University Colorado - Boulder USA 37.8

35 University California - Santa Barbara USA 37.0

36 University British Columbia Canada 36.3

36 University Texas Southwestern Med Center USA 36.3

38 Vanderbilt University USA 35.1

39 University Utrecht Netherlands 34.9

40 University Texas - Austin USA 34.8

41 University Paris 06 France 33.9

42 University California - Davis USA 33.6

43 Pennsylvania State University - University Park USA 33.5

44 Rutgers State University - New Brunswick USA 33.4

45 Tech University Munich Germany 33.3

46 Karolinska Inst Stockholm Sweden 33.0

47 University Edinburgh UK 32.9

48 University Paris 11 France 32.5

48 University Southern California USA 32.5

48 University Pittsburgh - Pittsburgh USA 32.5

51 University Munich Germany 32.4

52 University Rochester USA 32.0

53 Australian Natl University Australia 31.9

54 Osaka University Japan 31.5

55 University California - Irvine USA 31.4

56 University North Carolina - Chapel Hill USA 31.2

57 University Zurich Switzerland 31.1

57 University Maryland - Coll Park USA 31.1

59 University Copenhagen Denmark 31.0

60 University Bristol UK 30.6

61 McGill University Canada 30.4

62 Carnegie Mellon University USA 30.3

63 University Leiden Netherlands 29.8

64 University Heidelberg Germany 29.7

65 Case Western Reserve University USA 29.6

66 Moscow State University Russia 29.5

67 University Florida USA 29.3

68 University Oslo Norway 29.2

69 University Sheffield UK 28.8

69 Tohoku University Japan 28.8

71 Purdue University - West Lafayette USA 28.7

72 University Helsinki Finland 28.6

73 Ohio State University - Columbus USA 28.5

74 Uppsala University Sweden 28.4

75 Rice University USA 28.3

76 University Arizona USA 28.1

77 King's Coll London UK 28.0

78 University Manchester UK 27.9

79 University Goettingen Germany 27.4

80 Michigan State University USA 27.0

80 University Nottingham UK 27.0

82 Brown University USA 26.8

82 University Melbourne Australia 26.8

82 University Strasbourg 1 France 26.8

85 Ecole Normale Super Paris France 26.5

86 University Vienna Austria 26.3

86 Boston University USA 26.3

88 University Freiburg Germany 26.0

88 McMaster University Canada 26.0

90 Hebrew University Jerusalem Israel 25.9

91 University Basel Switzerland 25.8

92 Lund University Sweden 25.6

93 University Birmingham UK 25.5

93 University Roma - La Sapienza Italy 25.5

95 Humboldt University Berlin Germany 25.4

95 University Utah USA 25.4

97 Stockholm University Sweden 25.2

97 Nagoya University Japan 25.2

99 University Bonn Germany 25.1

99 Tufts University USA 25.1

101-152 Aarhus University Denmark \

101-152 Arizona State University - Tempe USA \

101-152 Baylor Coll Med USA \

101-152 Dartmouth Coll USA \

101-152 Emory University USA \

101-152 Georgia Inst Tech USA \

101-152 Hokkaido University Japan \

101-152 Indiana University - Bloomington USA \

101-152 Kyushu University Japan \

101-152 Natl University Singapore Singapore \

101-152 North Carolina State University - Raleigh USA \

101-152 Oregon State University USA \

101-152 State University New York - Stony Brook USA \

101-152 Tel Aviv University Israel \

101-152 Texas A&M University - Coll Station USA \

101-152 Tokyo Inst Tech Japan \

101-152 Tsukuba University Japan \

101-152 University Alberta Canada \

101-152 University Amsterdam Netherlands \

101-152 University Bern Switzerland \

101-152 University California - Riverside USA \

101-152 University California - Santa Cruz USA \

101-152 University Frankfurt Germany \

101-152 University Geneva Switzerland \

101-152 University Georgia USA \

101-152 University Ghent Belgium \

101-152 University Glasgow UK \

101-152 University Groningen Netherlands \

101-152 University Hamburg Germany \

101-152 University Hawaii - Manoa USA \

101-152 University Illinois - Chicago USA \

101-152 University Iowa USA \

101-152 University Kiel Germany \

101-152 University Leeds UK \

101-152 University Leuven Belgium \

101-152 University Libre Bruxelles Belgium \

101-152 University Liverpool UK \

101-152 University Louvain Belgium \

101-152 University Massachusetts - Amherst USA \

101-152 University Miami USA \

101-152 University Milan Italy \

101-152 University Muenster Germany \

101-152 University Paris 07 France \

101-152 University Pisa Italy \

101-152 University Queensland Australia \

101-152 University Sussex UK \

101-152 University Sydney Australia \

101-152 University Tennessee - Knoxville USA \

101-152 University Tuebingen Germany \

101-152 University Virginia USA \

101-152 University Wuerzburg Germany \

101-152 Weizmann Inst Sci Israel \

153-201 Cardiff University UK \

153-201 Coll France France \

153-201 Colorado State University USA \

153-201 Erasmus University Netherlands \

153-201 Florida State University USA \

153-201 Free University Amsterdam Netherlands \

153-201 Gothenburg University Sweden \

153-201 Iowa State University USA \

153-201 Mt Sinai Sch Med USA \

153-201 Natl Taiwan University China-tw \

153-201 Oregon Health & Sci University USA \

153-201 Queen's University Canada \

153-201 Rensselaer Polytechnic Inst USA \

153-201 Royal Inst Tech Sweden \

153-201 Seoul Natl University South Korea \

153-201 Swiss Fed Inst Tech - Lausanne Switzerland \

153-201 Tech University Denmark Denmark \

153-201 University Alabama - Birmingham USA \

153-201 University Autonoma Madrid Spain \

153-201 University Calgary Canada \

153-201 University Cincinnati - Cincinnati USA \

153-201 University Connecticut - Storrs USA \

153-201 University Delaware USA \

153-201 University Grenoble 1 France \

153-201 University Koeln Germany \

153-201 University Leicester UK \

153-201 University Leipzig Germany \

153-201 University Mainz Germany \

153-201 University Marburg Germany \

153-201 University Maryland - Baltimore USA \

153-201 University Montpellier 2 France \

153-201 University Montreal Canada \

153-201 University Nacl Autonoma Mexico Mexico \

153-201 University Nebraska - Lincoln USA \

153-201 University New South Wales Australia \

153-201 University Notre Dame USA \

153-201 University Padua Italy \

153-201 University Sao Paulo Brazil \

153-201 University Southampton UK \

153-201 University Texas Health Sci Center - Houston USA \

153-201 University Texas M.D. Anderson Cancer Center USA \

153-201 University Turin Italy \

153-201 University Wageningen Netherlands \

153-201 University Waterloo Canada \

153-201 University Western Australia Australia \

153-201 Virginia Commonwealth University USA \

153-201 Virginia Tech USA \

153-201 Washington State University - Pullman USA \

153-201 Yeshiva University USA \

202-301 Brandeis University USA \

202-301 Chalmers University Tech Sweden \

202-301 Chinese University Hong Kong China-hk \

202-301 Dalhousie University Canada \

202-301 Delft University Tech Netherlands \

202-301 Ecole Polytechnique France \

202-301 Free University Berlin Germany \

202-301 George Mason University USA \

202-301 George Washington University USA \

202-301 Georgetown University USA \

202-301 Hiroshima University Japan \

202-301 Hong Kong University Sci & Tech China-hk \

202-301 Indian Inst Sci India \

202-301 Innsbruck University Austria \

202-301 Kansas State University USA \

202-301 Keio University Japan \

202-301 Kobe University Japan \

202-301 London Sch Economics UK \

202-301 Louisiana State University - Baton Rouge USA \

202-301 Monash University Australia \

202-301 Okayama University Japan \

202-301 Peking University China \

202-301 Polytechnic Inst Milan Italy \

202-301 Queen Mary Coll UK \

202-301 State University New York - Albany USA \

202-301 State University New York - Buffalo USA \

202-301 Swedish University Agr Sci Sweden \

202-301 Syracuse University USA \

202-301 Tech University Aachen Germany \

202-301 Tech University Berlin Germany \

202-301 Technion Israel Inst Tech Israel \

202-301 Thomas Jefferson University USA \

202-301 Trinity Coll Dublin Ireland \

202-301 Tsing Hua University China \

202-301 Tulane University USA \

202-301 Umea University Sweden \

202-301 University Adelaide Australia \

202-301 University Alaska - Fairbanks USA \

202-301 University Antwerp Belgium \

202-301 University Auckland New Zealand \

202-301 University Barcelona Spain \

202-301 University Bochum Germany \

202-301 University Bologna Italy \

202-301 University Bordeaux 1 France \

202-301 University Buenos Aires Argentina \

202-301 University Cape Town South Africa \

202-301 University Colorado Health Sci Center USA \

202-301 University Dundee UK \

202-301 University Durham UK \

202-301 University East Anglia UK \

202-301 University Erlangen Nuernberg Germany \

202-301 University Florence Italy \

202-301 University Genoa Italy \

202-301 University Graz Austria \

202-301 University Guelph Canada \

202-301 University Halle - Wittenberg Germany \

202-301 University Hong Kong China-hk \

202-301 University Houston USA \

202-301 University Kansas - Lawrence USA \

202-301 University Karlsruhe Germany \

202-301 University Kentucky USA \

202-301 University Laval Canada \

202-301 University Liege Belgium \

202-301 University Lyon 1 France \

202-301 University Manchester Inst Sci & Tech UK \

202-301 University Manitoba Canada \

202-301 University Massachusetts - Worcester USA \

202-301 University Med & Dentistry New Jersey USA \

202-301 University Missouri - Columbia USA \

202-301 University Naples Federico II Italy \

202-301 University New Mexico - Albuquerque USA \

202-301 University Newcastle UK \

202-301 University Nijmegen Netherlands \

202-301 University Oregon USA \

202-301 University Otago New Zealand \

202-301 University Ottawa Canada \

202-301 University Paris 05 France \

202-301 University Reading UK \

202-301 University Regensburg Germany \

202-301 University Rhode Island USA \

202-301 University Saskatchewan Canada \

202-301 University South Carolina - Columbia USA \

202-301 University South Florida USA \

202-301 University Southern Denmark Denmark \

202-301 University St Andrews UK \

202-301 University Stuttgart Germany \

202-301 University Szeged Hungary \

202-301 University Texas Health Sci Center - San Antonio USA \

202-301 University Texas Med Branch - Galveston USA \

202-301 University Toulouse 3 France \

202-301 University Turku Finland \

202-301 University Twente Netherlands \

202-301 University Ulm Germany \

202-301 University Vermont USA \

202-301 University Warwick UK \

202-301 University Western Ontario Canada \

202-301 University York UK \

202-301 Wake Forest University USA \

202-301 Wayne State University USA \

202-301 Yonsei University South Korea \

302-403 Bar Ilan University Israel \

302-403 Ben Gurion University Israel \

302-403 Carleton University Canada \

302-403 Charles University Prague Czech \

302-403 Chiba University Japan \

302-403 City University Hong Kong China-hk \

302-403 City University New York - City Coll USA \

302-403 Clemson University USA \

302-403 Ecole Natl Super Mines - Paris France \

302-403 Ecole Normale Super Lyon France \

302-403 Ecole Super Phys & Chem Industry France \

302-403 Eindhoven University Tech Netherlands \

302-403 Fudan University China \

302-403 Gifu University Japan \

302-403 Gunma University Japan \

302-403 Hong Kong Polytechnic University China-hk \

302-403 Indiana University - Purdue University - Indianapolis USA \

302-403 Jagiellonian University Poland \

302-403 Kanazawa University Japan \

302-403 Korea Advanced Inst Sci & Tech South Korea \

302-403 Lehigh University USA \

302-403 Macquarie University Australia \

302-403 Med Coll Georgia USA \

302-403 Med Coll Wisconsin USA \

302-403 Med University South Carolina USA \

302-403 Michigan Tech University USA \

302-403 Nagasaki University Japan \

302-403 Nanjing University China \

302-403 Nanyang Tech University Singapore \

302-403 Natl Tsing Hua University China-tw \

302-403 Nihon University Japan \

302-403 Niigata University Japan \

302-403 Norwegian University Sci & Tech Norway \

302-403 Open University UK \

302-403 Pohang University Sci & Tech South Korea \

302-403 Queen's University Belfast UK \

302-403 Royal Veterinary & Agr University Denmark \

302-403 San Diego State University USA \

302-403 Simon Fraser University Canada \

302-403 Southern Methodist University USA \

302-403 St Petersburg State University Russia \

302-403 St. Louis University USA \

302-403 Sungkyunkwan University South Korea \

302-403 Tech University Braunschweig Germany \

302-403 Tech University Darmstadt Germany \

302-403 Tech University Dresden Germany \

302-403 Tech University Helsinki Finland \

302-403 Temple University USA \

302-403 Texas Tech University USA \

302-403 Tokyo Med & Dent University Japan \

302-403 Tokyo Metropolitan University Japan \

302-403 Tokyo University Agr & Tech Japan \

302-403 University Aberdeen UK \

302-403 University Athens Greece \

302-403 University Bath UK \

302-403 University Bayreuth Germany \

302-403 University Bergen Norway \

302-403 University Bielefeld Germany \

WHAT IS THE DIFFERENCE BETWEEN ACCURACY AND PRECISION?

2009-11-06T02:58:00.000-08:00

WHAT IS THE DIFFERENCE BETWEEN ACCURACY AND PRECISION?

Accuracy is defined as, "The ability of a measurement to match the actual value of the quantity being measured". If in reality it is 34.0 F outside and a temperature sensor reads 34.0 F, then than sensor is accurate.

Precision is defined as, "(1) The ability of a measurement to be consistently reproduced" and "(2) The number of significant digits to which a value has been reliably measured". If on several tests the temperature sensor matches the actual temperature while the actual temperature is held constant, then the temperature sensor is precise. By the second definition, the number 3.1415 is more precise than the number 3.14

An example of a sensor with BAD accuracy and BAD precision: Suppose a lab refrigerator holds a constant temperature of 38.0 F. A temperature sensor is tested 10 times in the refrigerator. The temperatures from the test yield the temperatures of: 39.4, 38.1, 39.3, 37.5, 38.3, 39.1, 37.1, 37.8, 38.8, 39.0. This distribution shows no tendency toward a particular value (lack of precision) and does not acceptably match the actual temperature (lack of accuracy).

An example of a sensor with GOOD accuracy and BAD precision: Suppose a lab refrigerator holds a constant temperature of 38.0 F. A temperature sensor is tested 10 times in the refrigerator. The temperatures from the test yield the temperatures of: 37.8, 38.3, 38.1, 38.0, 37.6, 38.2, 38.0, 38.0, 37.4, 38.3. This distribution shows no impressive tendency toward a particular value (lack of precision) but each value does come close to the actual temperature (high accuracy).

An example of a sensor with BAD accuracy and GOOD precision: Suppose a lab refrigerator holds a constant temperature of 38.0 F. A temperature sensor is tested 10 times in the refrigerator. The temperatures from the test yield the temperatures of : 39.2, 39.3, 39.1, 39.0, 39.1, 39.3, 39.2, 39.1, 39.2, 39.2. This distribution does show a tendency toward a particular value (high precision) but every measurement is well off from the actual temperature (low accuracy).

An example of a sensor with GOOD accuracy and GOOD precision: Suppose a lab refrigerator holds a constant temperature of 38.0 F. A temperature sensor is tested 10 times in the refrigerator. The temperatures from the test yield the temperatures of: 38.0, 38.0, 37.8, 38.1, 38.0, 37.9, 38.0, 38.2, 38.0, 37.9. This distribution does show a tendency toward a particular value (high precision) and is very near the actual temperature each time (high accuracy).

The goal of any meteorological instrument is to have high accuracy (sensor matching reality as close as possible) and to also have a high precision (being able to consistently replicate results and to measure with as many significant digits as appropriately possible). Meteorological instruments, including radar, need to be calibrated in order that they sustain high accuracy and high precision.

Kreysigs Advanced Mathematics 9th Ed

2009-11-03T07:39:00.000-08:00

   Part1
   Part2
   Part3
   Part4
   Part5
   Part6

Kreyszig Advanced Engineering Mathematics Instructor's Manual 9th Ed

2009-11-01T05:01:00.000-08:00

Instructors Manual for Advanced Engineering Mathematics 9th ED

How To Merge/ Join Files Using HJSplit

2009-11-01T02:50:00.000-08:00

How To Merge/ Join Files Using HJSplit

With HJSplit you can not only split files, but also join the split parts back together again. To start Joining you files, follow these simple steps.
After clicking on the ‘Join’ button in the main HJSplit screen, you will see the following screen:

Make sure the set of split parts (set of files ending in .001, .002, .003, etc.) to be joined all reside inside the same directory. Click on the button ‘Input file’, in the screen directly above, which will open the dialog shown directly below:

Note that only the first file in the set of split parts (the .001 file) is visible in this dialog. Note that it is important that all split parts are in the same folder. When the other files which belong to the set of split parts (.002, .003, .004, etc.) are in the same folder, HJSplit will automatically find them during joining.

After pressing Open, the name and path of the file you just selected will appear in the input file box, please see below:

Now press the Start button to merge all the files into one file.

If you think there are some other softwares that can do better job than these, let us know in the comments.

Must Read

2009-11-01T01:32:00.000-07:00

Needed Software

Now on My file will be in split format .You can download the HJSplit from my blog or from other site

you will need it to join the parts together.Tutorial is on board now.Any help will be provided on quest.!!!!!!!

HJSPLIT

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