technology

What is Nanotechnology?

2007-09-12T02:25:00.000-07:00

A basic definition: Nanotechnology is the engineering of functional systems at the molecular scale. This covers both current work and concepts that are more advanced.In its original sense, 'nanotechnology' refers to the projected ability to construct items from the bottom up, using techniques and tools being developed today to make complete, high performance products.

The Meaning of Nanotechnology

2007-09-12T02:24:00.002-07:00

When K. Eric Drexler (right) popularized the word 'nanotechnology' in the 1980's, he was talking about building machines on the scale of molecules, a few nanometers wide—motors, robot arms, and even whole computers, far smaller than a cell. Drexler spent the next ten years describing and analyzing these incredible devices, and responding to accusations of science fiction. Meanwhile, mundane technology was developing the ability to build simple structures on a molecular scale. As nanotechnology became an accepted concept, the meaning of the word shifted to encompass the simpler kinds of nanometer-scale technology. The U.S. National Nanotechnology Initiative was created to fund this kind of nanotech: their definition includes anything smaller than 100 nanometers with novel properties.Much of the work being done today that carries the name 'nanotechnology' is not nanotechnology in the original meaning of the word. Nanotechnology, in its traditional sense, means building things from the bottom up, with atomic precision. This theoretical capability was envisioned as early as 1959 by the renowned physicist Richard Feynman.I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously. . . The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big. — Richard Feynman, Nobel Prize winner in physicsBased on Feynman's vision of miniature factories using nanomachines to build complex products, advanced nanotechnology (sometimes referred to as molecular manufacturing) will make use of positionally-controlled mechanochemistry guided by molecular machine systems. Formulating a roadmap for development of this kind of nanotechnology is now an objective of a broadly based technology roadmap project led by Battelle (the manager of several U.S. National Laboratories) and the Foresight Nanotech Institute.Shortly after this envisioned molecular machinery is created, it will result in a manufacturing revolution, probably causing severe disruption. It also has serious economic, social, environmental, and military implications.

Four Generations

2007-09-12T02:24:00.001-07:00

Mihail (Mike) Roco of the U.S. National Nanotechnology Initiative has described four generations of nanotechnology development (see chart below). The current era, as Roco depicts it, is that of passive nanostructures, materials designed to perform one task. The second phase, which we are just entering, introduces active nanostructures for multitasking; for example, actuators, drug delivery devices, and sensors. The third generation is expected to begin emerging around 2010 and will feature nanosystems with thousands of interacting components. A few years after that, the first integrated nanosystems, functioning (according to Roco) much like a mammalian cell with hierarchical systems within systems, are expected to be developed.

Dual-Use Technology

2007-09-12T02:23:00.000-07:00

Like electricity or computers before it, nanotech will offer greatly improved efficiency in almost every facet of life. But as a general-purpose technology, it will be dual-use, meaning it will have many commercial uses and it also will have many military uses—making far more powerful weapons and tools of surveillance. Thus it represents not only wonderful benefits for humanity, but also grave risks. A key understanding of nanotechnology is that it offers not just better products, but a vastly improved manufacturing process. A computer can make copies of data files—essentially as many copies as you want at little or no cost. It may be only a matter of time until the building of products becomes as cheap as the copying of files. That's the real meaning of nanotechnology, and why it is sometimes seen as "the next industrial revolution."My own judgment is that the nanotechnology revolution has the potential to change America on a scale equal to, if not greater than, the computer revolution. — U.S. Senator Ron Wyden (D-Ore.)The power of nanotechnology can be encapsulated in an apparently simple device called a personal nanofactory that may sit on your countertop or desktop. Packed with miniature chemical processors, computing, and robotics, it will produce a wide-range of items quickly, cleanly, and inexpensively, building products directly from blueprints.

Nanotech Facts

2007-09-12T02:22:00.000-07:00

Nanotech FactsUsing the scanning tunneling microscope (STM), electron formations can be viewed. At left, electrons are surrounded by 48 iron atoms, individually positioned with the same STM used to image them. The image was created and colorized at the IBM Almaden research laboratory in California.The transition of nanotechnology research into manufactured products is limited today, but some products moved relatively quickly to the marketplace and already are having significant impact. For example, a new form of carbon, —the nanotube—was discovered by Sumio Iijima in 1991. In 1995, it was recognized that carbon nanotubes were excellent sources of field-emitted electrons. By 2000, the “jumbotron lamp,” a nanotube-based light source that uses these field-emitted electrons to bombard a phosphor, was available as a commercial product. (Jumbotron lamps light many athletic stadiums today.) By contrast, the period of time between the modeling of the semiconducting property of germanium in 1931 and the first commercial product (the transistor radio) was 23 years. The discovery of another nanoscale carbon form, C60, the fullerene (also called the buckyball) brought the Nobel Prize in Chemistry in 1996 to Robert F. Curl Jr., Sir Harold W. Kroto, and Richard E. Smalley. It also started an avalanche of research into not only the novel characteristics of C60, but also other nanoscale materials.Nanoscale science was enabled by advances in microscopy, most notably the electron, scanning tunneling and atomic force microscopes, among others. The 1986 Nobel Prize for Physics honored three of the inventors of the electron and scanning tunnel microscopes, Ernst Ruska, Gerd Binnig and Heinrich Rohrer.

Database

2007-08-14T02:41:00.001-07:00

DATA:-Data is define as the representation of facts, concepts or instructions in a formalized manner suitable for communication , interpretation or processing by human or electronic machine . Data is represented with the help of characters LIKE alphabets(a-z,A-Z),digits(0-9)or special characters(+,-,/,<,>,etc).DATA FIELD OR ITEM:-A set of characters which are used together to represent a specific data elements are known as DATA FIELD OR ITEM.In the table the example of data field is ROLLNO, MARKSRECORD:-A record is a collection of fields or it is the row in a giventable that express a specific objects with their properties.INFORMATION:-The data that comes out after the processing on which the decision are take place is called INFORMATION.DATA PROCESSING:-The data processing is a process of converting a data into information on which the decisions can be taken. LIKE marks taken by a student on which he will be declare PASS or FAIL.DATABASE:-Database is collection of interrelated data i.e it is composed of collection of files that are linked in such a way that information from one file may be combine with information from other fileA database is also define as a collection of interrelated data stored together without harmful or unnecessary redundancy to serve multiple application.EXAMPLE:- A database of a given school may contain files or tables like about students, staff, funds etc.DATABASE has some following implicit properties1) A database represents some aspect of real world called miniworld. Changes to miniworld are reflected in database.2) A database is designed, built with data for specific purpose. It has an intended group of users.3) A database is a logically coherent collection of data with some inherent meaning.

routers

2007-08-14T02:40:00.000-07:00

Routers are those connectivity devices that connect two different networks means they are used two form more bigger network by connecting two networks if and only if that two different networks have SAME PROTOCOLUnlike bridges router when connect two n/w it never make a single n/w means two n/w are connected and their address space is also different means they exists as two n/w’s (different) which are able to communicate with each other.But bridge when connect two n/w it form a one bigger means they have common address space means they have SAME NETWORK ADDRESS.Router also performs ROUTING which means to finding out BEST path when there are multiple paths exists between two hosts.