Know About Electromagnetic Meta materials

Meta materials are the artificially engineered materials which have the properties that are not found in the nature. The structure of meta materials and not composition that define its properties. Electromagnetic meta materials are the type of meta materials which are designed to interact with and control electromagnetic waves. Electromagnetic waves can be any type of waves in the electromagnetic spectrum and they can have wavelengths of thousands of kilometers to trillionths of a meter.

When the electromagnetic waves enter the material, the electric and magnetic fields of the wave cause electrons within the material to move around. The materials are used to control and manipulate the light waves by means of exchange of electromagnetic energy with the atoms and molecules of a material and these are the basis for formation of electromagnetic devices.

The size and spacing of the atoms with in the material is dependent on the order of angstroms which means that visible light waves, which are hundreds of nanometers in size, or longer wavelength waves cannot even come close to resolving the atomic structure. One can't see the individual atoms because the light perceived is so much larger than the atomic scale although the materials are formed from the collection of the atoms. So it is possible to estimate the discrete atoms and molecules of a material as a continuous substance, and properties of these materials not only derived from the individual atoms and molecules but also derived from the interactions between them with in that material.

What is a Nanowire Battery and Know Its Uses

Electric vehicles are at present making use of Lithium ion batteries, but now a new type of battery called nanowire battery is developed. It consists of stainless steel anode covered in silicon nanowires. Silicon stores large amount of graphite and allows far greater energy density on the anode, thus reducing the mass of the battery.

This nanowire batteries stores 10 times more electricity than the traditional lithium ion batteries. This can be very useful for the auto manufacturers who produce electric cars. These could also be used in homes or offices to store electricity generated by rooftop solar panels. Electrical storage capacity of these batteries depends on how much lithium can be held in the battery's anode and this anode is typically made up of carbon. But silicon has a much higher capacity than carbon.

Working of these batteries is explained by silicon placed in the battery swells as it absorbs the positively charged lithium ions and it shrinks while using the battery because lithium is drawn out of the silicon. This expansion and shrinkage cycle causes the silicon to pulverize, degrading the performance of the battery. Cui's battery addresses this problem with nanotechnology. In this battery lithium is stored in a forest of tiny silicon nanowires, each with a diameter one thousandth the thickness of a sheet of paper. These wires can store a charge of about 2,000 milliamp hours per gram. Researchers in the past made electrodes from pure crystalline silicon nanowire and these wires had triple the storage capacity of graphite electrodes but they lasted up to only 20 cycles.

What is Algae Fuel and Its Derivatives

Algae fuel is derived from algae and it is an alternative source to the fuel derived from fossils. They do not reduce the carbon dioxide present in the atmosphere but they reduce the introduction of new CO2 by displacing fossil hydrocarbon fuels. Several companies and many government agencies are making efforts to reduce the capital and operating costs and make algae fuel production commercially viable. Following are the derivatives of the algae fuel:

Bio diesel:
Some species of algae can produce up to 60 percent of their dry weight in the form of oil. Micro algae are also capable of producing high amount of biomass and usable oil because they grow in aqueous suspension, where they have more efficient access to water, CO2 and dissolved nutrients. Further this oil is turned in to bio diesel which can be used in automobiles.

Biobutanol:
Biobutanol has an energy density 10 percent less than gasoline and greater than that of methanol or ethanol and in most of the gasoline engines Butanol can be used in place of gasoline with no modifications. This fuel can be derived from the algae by using inky solar powered bio refinery.

Methane:
Methane is a form of natural gas and it can be produced from algae through different methods which includes Gasification, pyrolysis and aerobic digestion.

Bio gasoline:
It is a type of gasoline produced from biomass such as algae, and it contains 6 to 12 carbon atoms per molecule. It can be used in internal combustion engines.

Jet Fuel:
The International Air Transport Association, supports research, development and deployment of algal fuels. The algae fuels are processed through various stages to make it suitable enough to run an airplane.

Algae fuels are becoming more popular as these will reduce the dependency on fossil fuels. Algae fuels are more eco friendly.

Different Types of Nano Particles Used in Biotechnology

Nano particles exist in different sizes, shapes, and materials, and with various chemical and surface properties. Here are the some of the basic properties and the uses of some nano particles in the field of biotechnology:

Fullereness:
This category includes Buckyballs and Carbon tubes, they are carbon based, lattice like, potentially porous molecules.

Liposomes:
These are lipid based liquid crystals and they have the capability of breaking down inside cells once their delivery function has been met. Because of this property they are extensively used in the pharmaceutical and cosmetic industries.

Quantum Dots:
These are nanosized semiconductors that, depending on their size, can emit light in all colors of the rainbow. These have been used in biotechnology for cell labelling and imaging, particularly in cancer imaging studies. These are sometimes also called as nanocrystals.

Dendrimers:
These are highly branched structures and they have multiple molecular hooks on their surfaces that can be used to attach cell-identification tags, fluorescent dyes, enzymes and other molecules and this is the one property which made them widely used in nanomedicine.

Liquid Crystals:
These are composed of organic liquid crystal materials that looks like naturally occurring bio molecules like proteins or lipids. These can target the specific areas of the body where tissues are inflamed or tumors are found.

Nanorods:
These are often made up of semiconducting materials and used in nanomedicine as imaging and contrast agents.

Super paramagnetic nanoparticles:
These molecules are attracted to a magnetic field and nanoparticles of iron oxide with diameters in the 5 to 100 nm range, have been used for selective magnetic bio separations. Super paramagnetic iron oxide nanoparticles (SPION) are applied for drug delivery and gene transfection.

Know About Biotechnology and Its Branches

Biotechnology is the field of applied biology that uses various micro organisms and living processes in engineering, medicine, technology and other to get the required results. Biotechnology is mainly applied in four different fields which includes health care, crop production, agriculture and non food uses of crops and other products.

Following are the important branches of biotechnology:
Bio informatics:
Bio informatics is the branch of biotechnology which uses computation methods to solve the biological problems and makes the rapid organization and analysis of biological data possible. It can also be referred as computational biology and it plays an important role in various areas such as functional genomics, structural genomics and forms a key component in the biotechnology and other pharmaceutical sectors.

Red Biotechnology:
This is the branch of biotechnology which has its applications in medical processes, some of the examples are designing the organisms to produce antibiotics and engineering of genetic cures through genetic manipulation.

White Biotechnology:
It is the biotechnology applied to industrial processes and it is also known as industrial biotechnology. It is the field in which the organisms are designed to produce useful chemical, using of enzymes to produce chemicals or to destroy hazardous chemicals. White biotechnology consumes less resources than traditional processes used to produce industrial goods.

Green Biotechnology:
Green biotechnology is applied to agricultural processes, and green biotechnology produces more environmental solutions than traditional methods. An example of green biotechnology is selection and domestication of plants via micro propagation.

Apart from the above said branches, there is also another branch which involves, investment and economic out put of all these types of applied bio technologies and is termed as bio economy.

All About Mobile Scanning Systems

Mobile scanning systems help to scan and register data from moving objects/platforms such as trains, cars, busses, boats, etc. Generally, mobile scanning systems are supplemented by attitude and position sensors (video, laser range, positioning, orientation, etc). IMU (Inertial Measurement Unit) and GPS (Global Positioning System) are some examples of these sensors.

Mobile scanning systems help to overcome many limitations of radial laser scanning. Mobile scanning systems can digitalize 3-D (three dimensional) models of real world terrain. In order to make this workout a combination of sensors is placed on a mobile platform which is in motion against the target terrain that needs to be digitized. These sensors result cause data fusion that constructs an accurate 3 D model of the target terrain.

The efficiency of a mobile scanning system can be measured in terms of the speed and quality (accuracy, resolution, etc) in construction of the 3D data. Recently released Riegl’s VMX-250 can collect 600,000 measurements per second.

Mobile scanning systems are generally used in mapping of waterways, railroads, highways, etc. It can also in mapping out open put mines, construction sites, etc.

Camcorders in Entertainment and Movies

A camcorder is a portable consumer electronics device for recording video and audio using a built-in recorder unit. The camcorder contains both a video camera and a video recorder in one unit, hence its compound name. This compares to previous technology where an acquisition and recording devices would be separate. The earliest camcorders, developed by companies such as JVC, Sony, and Kodak, used analog videotape. Since the 1990s recording onto digital tape has become the norm. Starting from early 2000s tape as storage media is being gradually replaced with tape-free solutions like optical disks, hard disk drives and solid-state memory. All tape-based camcorders have removable media in form of video cassettes. Solid-state camcorders can have either removable media in form of memory cards, or built-in memory, or both. HDD-based camcorders usually have non-removable media in form of a hard disk drive. Camcorders that do not use magnetic tape are often called tapeless camcorders. Camcorders that use two different types of media, like built-in HDD and memory card, are often called hybrid camcorders.

Entertainment and Movies
Camcorders are often used in the production of low-budget TV shows where the production crew does not have access to more expensive equipment. There are even examples of movies shot entirely on consumer camcorder equipment. In addition, many academic filmmaking programs have switched from 16mm film to digital video, due to the vastly reduced expense and ease of editing of the digital medium as well as the increasing scarcity of film stock and equipment. Some camcorder manufacturers cater to this market, particularly Canon and Panasonic, who both support “24p” video in some of their high-end models for easy film conversion.

Even high-budget cinema is done using camcorders in some cases; George Lucas used Sony CineAlta camcorders in two of his three Star Wars prequel movies. This process is referred to as digital film.

Causes and Limitations of Thrashing

In computer science, thrash is the term used to describe a degenerate situation on a computer where increasing resources are used to do a decreasing amount of work. Usually it refers to two or more processes accessing a shared resource repeatedly such that serious system performance degradation occurs because the system is spending a disproportionate amount of time just accessing the shared resource. Resource access time may generally be considered as wasted, since it does not contribute to the advancement of any process.

Cause of Thrashing
Thrashing results in several performance problems. Consider the following scenario, which is based on actual behavior of early paging systems.

The operating system monitors CPU utilization. If the CPU utilization is too low, we increase the degree of multiprogramming by introducing new processes to the system. A global page-replacement algorithm is used; it replaces pages without regard to the process that they belong. Now suppose that a process enters a new phase in its execution and needs more frames. It starts faulting and taking frames away from other processes. These processes need those pages, however, and so they also fault, taking frames away from other processes. These faulting processes must use the paging device to swap pages in and out. As they queue up for the paging device, the ready queue empties. As the processes wait for the paging device, CPU utilization decreases.

The CPU scheduler sees the decreasing CPU utilization and increases the degree of multiprogramming as a result. The new process tries to get started by taking frames from running processes, causing more page faults and a longer queue for the paging device. As a result CPU utilization drops even further, and CPU scheduler tries to increase the degree of multiprogramming even more. Thrashing has occurred, and system throughput plunges. The page fault rate increases tremendously. As a result, the effective memory-access time increases. No work is being done.

Limit the effect of Thrashing
The effect of thrashing can be limited by using a local replacement algorithm. With local replacement, if one process starts thrashing, it cannot steal frames from another process and cause the latter to thrash as well. However, the problem is not entirely solved. If the processes are thrashing they will be in the queue for the paging device. The average service time for a page fault will increase because of the longer average queue for the paging device. Thus, the effective access time will increase even for a process that is not thrashing.

To prevent thrashing we must provide a process with as many frames as it needs. But how do we know how many frames it “needs”?. There are several techniques. The working-set strategy is one such. This approach defines the locality model of process execution.

The Global Telecommunications System

The Global Telecommunications System (GTS) is a global network for the transmission of meteorological data from weather stations, satellites and numerical weather prediction centers.

The GTS consists of an integrated network of point-to-point circuits, and multi-point circuits, which interconnect meteorological telecommunication centers. The circuits of the GTS are composed of a combination of terrestrial and satellite telecommunication links. They comprise point-to-point circuits, point-to-multi-point circuits for data distribution, multi-point-to-point circuits for data collection, as well as two-way multi-point circuits. Meteorological Telecommunication Centers are responsible for receiving data and relaying it selectively on GTS circuits. The GTS is organized on a three level basis:

• The Main Telecommunication Network (MTN)
• The Regional Meteorological Telecommunication Networks (RMTNs)
• The National Meteorological Telecommunication Networks (NMTNs)

Satellite-based data collection and/or data distribution systems are integrated in the GTS as an essential element of the global, regional and national levels of the GTS. Data collection systems operated via geostationary or near-polar orbiting meteorological/environmental satellites, including the Argos System, are widely used for the collection of observational data from data collection platforms. Marine data are also collected through the International Maritime Mobile Service and Inmarsat satellites.

Related Links:
Unified communications
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Important Specifications when evaluating an LCD monitor

LCD monitor is a flat panel display, which uses liquid crystals. Although laptops have used LCD’s as their flat panel technology almost exclusively, LCD is also the most popular for flat panel desktop monitors. Toward the end of 2003, sales of LCD displays for desktops overtook CRTs for the first time.

Important Specifications
The following are the important factors to consider when evaluating an LCD monitor:

Resolution:
The horizontal and vertical size expressed in pixels (e.g., 1024×768). Unlike CRT monitors, LCD monitors have a native-supported resolution for best display effect.

Dot pitch:
Dot pitch is the distance between the centers of two adjacent pixels. The smaller the dot pitch size, the less granularity is present, resulting in a sharper image. Dot pitch may be the same both vertically and horizontally, or different.

Viewable size:
The size of an LCD panel measured on the diagonal and more specifically known as active display area.

Response time:
Response time is the minimum time necessary to change a pixel’s color or brightness. Response time is also divided into rise and fall time. For LCD Monitors, this is measured in BTB (black to black) or GTG (gray to gray). These different types of measurements make comparison difficult.

Refresh rate:
The number of times per second in which the monitor draws the data it is being given. A refresh rate that is too low can cause flickering and will be more noticeable on larger monitors. Many high-end LCD televisions now have a 120 Hz refresh rate current and former NTSC countries only. This allows for less distortion when movies filmed at 24 frames per second (fps) are viewed due to the elimination of telecine. The rate of 120 was chosen as the least common multiple of 24 fps (cinema) and 30 fps (TV).

Viewing angle, Brightness and Color support:
How many types of colors are supported? The amount of light emitted from the display

Contrast ratio:
Contrast ratio is the ratio of the intensity of the brightest bright to the darkest dark.

Aspect ratio:
The ratio of the width to the height Input ports (e.g., DVI, VGA, LVDS, or even S-Video and HDMI).