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KOAY ANNIE 091190404MARINA 091190502 SITI ATIKAH 091191308 NORSRI KURNIATI 091191028MOHD FARID 091190627

a form of energy exhibiting wave-like behavior as it travels through space.

It has both electric field and magnetic field components, which oscillate in phase perpendicular to each other and perpendicular to the direction of energy propagation.

Microwaves are electromagnetic waves with ranging from 1 millimeter to 1 meter equivalently with frequencies between 0.3 GHz and 300 GHz.

Microwaves are short waves of electromagnetic energy that travel at the speed of light.

Microwave signals propagate in straight lines. Microwaves are of a non-ionizing character. They do not have the

energy to cause chemical changes in substances as would happen in the case of radioactivity.

They are not refracted or reflected by ionized regions in the upper atmosphere.

The principle danger of microwaves is that body tissue can be affected in the same way that food is. Microwaves can cause burn tissue by heating up the water, fats, and sugars naturally found in human tissues. Fortunately, microwave radiation in kitchen appliances are very low.

Microwave radiation is the radiating wave movement in which microwave energy travels.

They are found between the radio waves and infrared waves in the electromagnetic spectrum.

They do not require a medium to travel through. They can pass through non-metal materials like plastic

and glass, meaning that objects made from these materials are 'microwave safe'.

But it get reflected off metal surfaces and causing sparks when one wave bounces into another.

A microwave oven will also produce sparks if turned on when nothing is inside the microwave, as the waves themselves will bounce off of each other.

Answer is No. Microwave radiation (at 2450 MHz) is non-ionizing, and in sufficient

intensity will simply cause the molecules in matter to vibrate, thereby causing friction, which produces the heat that cooks the food. Because of the lower frequencies and reduced energy, it does not have the same damaging and cumulative properties as ionizing radiation

Radioactive radiation is the frequency spectrum which in ionizing radiation. It is extraordinarily high in frequency. It is extremely powerful and penetrating.

Even at low levels, ionizing radiation can damage the cells of living tissue. These dangerous rays have enough energy and intensity to ionize the molecular structure of matter. Ionizing radiation can even cause genetic mutations.

As shown on the frequency spectrum diagram before, the ionizing range of frequencies includes X-rays, gamma rays, and cosmic rays.

Ionizing radiation is the sort of radiation we associate with radioactive substances like uranium, radium, and thermonuclear explosions.

Microwave oven are used microwave to cook food. Microwave are used to locate ships for navigation Data transmissions between stations on Earth and

between the Earth and satellites by microwave. Radar uses microwave radiation to detect the range,

speed, and other characteristics of remote objects. Radio astronomy uses microwaves determining the

distance to the Moon or mapping the invisible surface of Venus through cloud cover.

Microwave radio is used in broadcasting and telecommunication transmissions.

It use for reheating and heating frozen food it saves the cooking time Microwaves may not penetrate between thick pieces of food. Since the

microwaves are emitted from only one side of the oven which using a spinning plate to ensure that food cooks evenly.

Furthermore, the air in the microwave remains room temperature, so there is not form a crust. This is why microwaveable items come with a cardboard sleeve which reacts to the microwaves by becoming very hot, causing exterior heat on top of the pastry, thus forming a crust.

The microwaves do not escape out of the little holes in the oven is that microwaves have a wavelength of 12.4 cm. The conducting surface that has holes smaller than that will reflect the microwaves, rather than allowing them to pass through. Therefore, the food have potential exposure to radiation.

A microwave oven consists of a high voltage transformer, an electron tube called magnetron, a wave guide fan and a cooking chamber. The transformer passes electric energy to the magnetron and the magnetron converts this electric energy into microwave radiation.

These waves are passed into the enclosed oven cavity and get reflected by the walls of the oven. Therefore, they get absorbed in food or drink placed in the middle.

The waves have a positive and negative end which penetrate the food and agitate the water molecules contained in it. This is because water is polar molecules will rotate at same frequency with microwave.

Thus, all this agitation on the molecular level creates friction, which produces a large amount of heat and heats up the food.

As a result of the microwave absorption, the water molecules in the food begin to vibrate. This molecular movement produces heat and the resultant heat cooks the food. Foods that have higher concentrations of water molecules cook faster.

The thicker foods, the outer part is cooked by the microwaves and the inner part is cooked by conduction of heat from the heated outer part.

Microwave energy has proven to be an efficient and reliable form of heating for a wide range of industrial processes.

Not every industrial process can benefit from Microwave heating but when an application is found where Microwave energy can be utilized it will normally produce superior results. New applications for Industrial Microwave energy are being continually developed

rubber industry Microwave heating saves energy during

batch preheating of rubber before molding into parts such as gasket.

Heating by hot air, autoclaves, or salt baths is slow and difflcult because rubber conducts heat poorly But microwave energy rapidly heats the rubber within Its bulk, up to five tlmeS faster than hot air heating.

Rubber is continuously extruded, microwave heated and vulcanized, and formed into products such as weather stripping and seals for expansion joints.

FOOD PROCESS (TEMPERING) Tempering of frozen foods-raising the temperature

from 0 F, at which foods are solidly frozen, to 18 F to 20 F

This required in processing meat, such as hamburger, sausage, canned meat, and pet foods, contains significant amounts of ingredients that have been frozen and later tempered to permit further processing.

Tempering takes only 5 minutes, whereas older processes required 2 to 5 days.

It can be performed in-carton, without unpacking the meat, which simplifies processing and clean-up.

Tempering effectively replaces a batch process with a continuous one and provides a product of uniform temperature and texture, with excellent process control.

CERAMICS (CERAMIC FIRING) The final comosition of ceramic products depends

on the amount of time and the temperature at which they are fired.

High temperatures are required to achieve the desired strength and composition.

Laboratory investigations of microwave firing, which is faster than conventional firing, have produced ceramic compositions unattainable with furnace firing. It shows superior strength and purity.

These properties lead to a great potential for applications for products with high performance requirements, such as engine parts and rocket nozzles.

Known as Light Detection and Ranging or Laser Radar Laser + Receiver System = Lidar LiDAR measures distances It measures distances by sending pulses of laser light that

strike and reflect from the surfaces of the earth. LiDAR uses ultraviolet, visible, or infrared light to image

objects and can be used with a wide range of targets, including non-metallic objects, rocks, rain, chemical compounds, clouds and even single molecules.

LiDAR has been used extensively for atmospheric research and meteorology. Downward-looking LiDAR instruments fitted to aircraft and satellites are used for surveying and mapping.

A example is the NASA Experimental Advanced Research Lidar

The LiDAR system measures the time of pulse return. Laser radar depends on knowing the speed of light,

approximately 0.3 meters per nanosecond. Using that constant, we can calculate how far a returning light photon has traveled to and from an object:

Distance = (Speed of Light x Time of Flight) / 2 Laser generates an optical pulse. Pulse is reflected off an object and returns to the system

receiver. High-speed counter measures the time of flight from the start

pulse to the return pulse. Time of pulse return is converted to a distance by using the

formula above

when it operated on an airborne platform such as a fixed wing airplane or helicopter the system can map land cover, and structures (vegetation, buildings, etc.) with accuracies measured in centimeters.

Current systems acquire more than 100,000 pulses per second, enable them to cover more than 10,000 hectares in a day.

The advantage of LiDAR is that all measurements are made in three dimensions.

And even though the laser pulses cannot penetrate vegetation, some of the laser energy can often find a way through small gaps in the forest canopy to reach the ground.

Each outgoing laser pulse spreads out as it moves towards the ground, and will typically generate more than one “return” pulse – such as from the top of a tree canopy, and branches as well as the ground.

Day or NightNo.

Since LIDAR is an active sensor, LiDAR data can be acquired day or night as long as the atmosphere is clear.

Sunlight and Reflections/Angle of MeasurementSometimes.

A strong sunlight reflection off a highly reflective target may "saturate" a receiver, producing an invalid or less accurate reading. However, laser measurements are not usually affected by other reflections. Optech's scanning laser instruments scan laser pulses within a preferred range of angles. Instruments are designed to operate in daylight.

Dust and VaporYes.

Laser measurements can be weakened by interacting with dust and vapor particles, which scatter the laser beam and the signal returning from the target.

However, using return-pulse measurements can reduce this interference.

Target's Angle of ReposeNo.

Laser measurements can be made to targets at any angle.

No Background Noise 

     The laser is not affected by background noise.

Temperature No.

Laser measurements are based on the speed of light and are unaffected by temperature .

The four major components of LiDAR include:

Aircraft

GPS

Inertial Navigation System (INS)

Laser Scanner System

Rotor-wing (helicopters) and fixed-wing (airplanes) aircraft are used to collect LiDAR data. The laser scanner is precision mounted on the bottom of the aircraft--similar to arrangements used for frame mapping cameras. Typically, a minimum two-person crew (pilot and operator) is required.

LiDAR requires precise real-time positioning. A major part of the position solution is provided by using GPS technologies in a differential kinematic mode. This involves finding or establishing a well-surveyed GPS base station and co-initializing with the airborne GPS. The GPS provides the XYZ location of the aircraft--but this is just part of the position solution required

An inertial navigation system (INS) provides another critical part of the position solution. The INS records the pitch, roll and yaw of the aircraft (i.e., the angle that the body of the LiDAR sensor is pointing). Thus, the INS position and the GPS position give us the location of the sensor and the angle that is pointing.

The laser scanner system is the heart of the LiDAR system--it includes the laser source, the laser detector, the scanning mechanism, the electronics for timing the pulses and returns, and the computing power to process and record the data in real time.

The Laser Detector. The laser detector is co-mounted with the laser. Its job is to detect the laser light that

is reflected from the target back to the aircraft. Now, it may be helpful to point out that even though the laser may be sending out several thousand laser pulses per second, there is sufficient time to detect all of the reflected pulses before the next pulse is sent. In addition, the intensity value of each LiDAR return is often recorded. Intensity images can be very useful.

The Scanning Mechanism. The most common scanning mechanism is the oscillating mirror, however, there are

others including: rotating polygon scanners, fiber scanners, and Palmer scanners. Each has slightly different properties and resulting scanner patterns

Timing Electronics. Timing is everything in LiDAR. The laser is sending 4,000 to 100,000 light pulses per

second. Each pulse may reflect up to five return pulses--at the speed of light. Each return must be precisely timed in order to obtain an accurate range (using the formula D = r*t/2 ). This seemingly impossible task is accomplished with astounding accuracy.

Computing Power.

The computing resources to record and process LiDAR should not be taken for granted. LiDAR generates a lot of data in a very short time--staggering amounts of data for large areas. Data must be recorded, and often processed, in real-time (although significant portions of the processing is post-mission). Consider that each LiDAR return is numbered has its range calculated, then the look angle is determined, and the GPS and IMU data have to be incorporated. Finally, the LiDAR range and look angle information is converted to geographic X,Y, and Z coordinates.

LiDAR resource management applications fall into several categories:

1.Vegetation Mapping 2.Biology and conservation3.Automotive4.Military5.Archaeology6.Topographic Mapping

Vegetation Mapping used to measure the three-dimensional characteristics of plant canopies and can estimate the

vertical structure of vegetation communities

Characteristics such as tree height, canopy structure, and overall forest biomass and volume are

difficult to estimate from two-dimensional images and are time consuming and labor intensive

to generate using conventional field methods

LiDAR technology captures elevation information from the forest canopy as well as the ground

beneath and can be used to assess the complex three-dimensional patterns of canopy and forest-

stand structure such as tree density, stand height, basal area, leaf area index, and forest biomass

and volume

Knowledge about a community's vegetation composition, structure, and patterns is important

for a variety of natural-resource planning and monitoring activities, including assessing fuel

loads and fire risk, wildlife habitat, and impact from recreational activities, and monitoring

general forest trends and conditions

Biology and conservation

LIDAR has also found many applications in forestry. Canopy heights, biomass measurements, and leaf area

can all be studied using airborne LIDAR systems. Similarly, LIDAR is also used by many industries,

including Energy and Railroad, and the Department of Transportation as a faster way of surveying.

Topographic maps can also be generated readily from LIDAR, including for recreational use such as in the

production of orienteering maps.

In oceanography, LiDAR is used for estimation of phytoplankton fluorescence and generally biomass in the

surface layers of the ocean. Another application is airborne lidar bathymetry of sea areas too shallow

for hydrographic vessels.

In addition, the Save-the-Redwoods League is undertaking a project to map the tall redwoods on California's

northern coast. LIDAR allows research scientists to not only measure the height of previously unmapped trees

but to determine the biodiversity of the redwood forest. Stephen Sillett who is working with the League on the

North Coast LIDAR project claims this technology will be useful in directing future efforts to preserve and

protect ancient redwood trees.

Automotive

Automotive system designers develop sophisticated LIDAR systems to automatically control

vehicle speed and braking systems according to traffic conditions. Such systems can also

dynamically control distance from other vehicles and obstacles and even manage safety

features such as airbags. Advancements in this technology greatly improve driver comfort and

safety

Military

The military applications of lidar systems have included using them as range-finders to

determine the distance to a target, and for missile defense. The military usages of both lidar

systems and lasers have included range finding. As range finders, the U.S. Army has used lidar

systems on battlefields to determine the distance to a target, such as an enemy tank. In a range

finder application, a laser transmits a pulse while a receiver (often little more than a lens)

registers a pulse when back-scattered light is picked up by the receiver. A computer portion of

the system measures the time interval between the time when the laser pulse is emitted and the

reflected pulse is sensed. Because the speed of light is known, a measurement of the round-trip

distance between the laser pulse and the receiver indicates distance to target.

Archaeology

LIDAR has many applications in the field of archaeology including aiding in the planning of field

campaigns, mapping features beneath forest canopy, and providing an overview of broad,

continuous features that may be indistinguishable on the ground. LIDAR can also provide

archaeologists with the ability to create high-resolution digital elevation models (DEMs) of

archaeological sites that can reveal micro-topography that are otherwise hidden by vegetation.

LiDAR-derived products can be easily integrated into a Geographic Information System (GIS) for

analysis and interpretation. For example at Fort Beausejour - Fort Cumberland National Historic

Site, Canada, previously undiscovered archaeological features have been mapped that are related to

the siege of the Fort in 1755. Features that could not be distinguished on the ground or through

aerial photography were identified by overlaying hillshades of the DEM created with artificial

illumination from various angles. With LiDAR the ability to produce high-resolution datasets

quickly and relatively cheaply can be an advantage. Beyond efficiency, its ability to penetrate forest

canopy has led to the discovery of features that were not distinguishable through traditional geo-

spatial methods and are difficult to reach through field surveys.

Topographic Mapping LiDAR has become a widely used technique for generating high-resolution

topographic data such as digital elevation models (DEMs), digital terrain models

(DTMs), and digital surface models (DSMs), with vertical accuracies of 15 to 100

centimeters

Topographic information is critical for a wide variety of purposes, including

engineering projects (e.g., transportation, mining reclamations, urban planning),

hydrology and floodplain management, corridor mapping (e.g., for roads,

telecommunications), landside analysis, geological studies, and natural-resource

assessments

Elevation measurements from forest canopies, buildings, or other structures, along

with ground information, are all available in raw LiDAR data. Post-processing

techniques identify and remove non-ground features to produce accurate DEMs or

bare-earth DTMs. High accuracies result because of the horizontal posting or point

density of the LiDAR data, which can range from 1.5 to 9 meters