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General

posted 7 months 3 weeks ago

Most Popular Seminar Topics for Engineering Students

 

The below mentioned list may help students to select their seminars in most appropriate way.

 

1. Mobile train radio communication

2. Paper battery

3. Smart antenna for mobile communication

4. Smart note taker

5. Embedded web technology

6. Low energy efficiency wireless

7. Communication network design

8. Seminar on artificial passenger

9. Blue eyes technology

10. Touch screen technology

11. Traffic pulse technology

12. Pill camera

13. Night vision technology

14. Space mouse

15. Nano-technology

16. Global positioning system and its application

17. Tsunami warning system

18. Smart dust core architecture

19. Advanced technique for RTL

20. Debugging

21. Optical fiber communication

22. Digital image processing

23. Embedded system

24. Electronic watchdog

25. Telephone conversation recorder

26. Aeronautical Communications

27. Agent oriented programming

28. Air cars

29. Animatronics

30. Artificial Eye

31. Augmented reality

32. Automatic Teller Machine

33. Autonomic Computing

34. BIBS

35. Bi-cmos technology

36. Bimolecular Computers

37. BIOCHIPS

38. Bio-magnetism

39. Biometric technology

40. BLUE RAY

41. Bluetooth Based Smart Sensor Networks

42. Boiler Instrumentation

43. Brain-Computer Interface

44. Bluetooth technology

45. 3-G Vs Wi-Fi

46. Future generation wireless network

47. Bluetooth based smart sensor network.

48. White LED

49. Gesture recognition using accelerometer

50. Cellular digital data packet

51. Telecommunication Network PPT

52. Electrical Technical Seminar Topic on CAN-based Higher Layer Protocols and Profiles

53. Application of Swarm Robots

54. Embedded Systems B.tech Final Year Seminar Topic on Smart Phones technology

55. Future Satellite Communication B.tech Seminar Topic

56. 3D image technique and multimedia application

57. Storage area network

58. The making of quantum dots

59. The mp3 standard

60. The Vanadium Red ox Flow Battery System

61. Thermal infrared imaging technology

62. Turbo codes

63. Ultra wide band technology

64. Virtual Reality

65. Voice recognition based on artificial neural networks

66. Web based remote device monitoring

67. Organic electronics

68. Packet Cable Network

69. Packet Switching chips

70. Personal Area Network

71. Printable RFID circuits

72. Mesh Radio

73. Microelectronic Pills

74. Military Radars

75. Android

76. Control of environment parameter in a green house

77. 3D traditional and modeling

78. Home based wireless work monitoring system

79. Sun tracker

80. PC interfaced voice recognition system

81. Cyber security

 

 

 

 

82. Big data visualization

83. Interactive public display

84. Next generation mobile computing

85. Multicore memory coherence

86. Renewable Energy Source Biomass

87. Matter Energy

88. Fusion Technology

89. Electronic Ballast

90. Stepper Motor & its Application

91. Radial Feeder Protection

92. Solar Tower Technology

93. Electric Locomotive

94. Reactive Power Consumption in Transmission Line

95. Flexible A.C. Transmission

96. D.C. Arc Furnace

97. Performance Evaluation & EMI/EMC Testing of Energy Meter

98. Feeder Protective Relay

99. Hydrogen The Future Fuel

100. Quality of electrical power

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General

posted 10 months 3 weeks ago

 

We are using Satellites in different Sectors. Such as

Television
Telephones
Navigation
Business & Finance
Weather
Climate and Environmental Monitoring
Safety
Land Stewardship
Development
Space Science
 
Television And Satellites

A direct-broadcast satellite (DBS) is a type of artificial satellite which usually broadcasts satellite television signals for home reception.
 
The type of satellite television which uses direct-broadcast satellites is known as direct-broadcast satellite television (DBSTV) or direct-to-home television (DTHTV).The term "direct broadcast" is used to distinguish satellites which transmit radio or television signals directly to receivers in consumers' homes from other communications satellites which transmit signals to satellite ground stations, for example those which distribute cable television signals to cable head end facilities. Since home satellite television receivers use small dish antennas less than a meter in diameter, DBS satellites must have much higher downlink transmitter power than other communication satellites, which are received by larger dishes from 2 up to 50 meters diameter.
 
Telephone And Satellites
Satellites provide in-flight phone communications on airplanes, and are often the main conduit of voice communication for rural areas and areas where phone lines are damaged after a disaster. Satellites also provide the primary timing source for cell phones and pagers. In 1998, a satellite failure demonstrated this dependence; it temporarily silenced 80 percent of the pagers in the United States, National Public Radio was not able to distribute its broadcasts to affiliates and broadcasted only via its website, and on the CBS Evening News, the image of Dan Rather froze while the audio continued.
 
Navigation And Satellites
Satellite-based navigation systems like the Navstar Global Positioning Systems (known colloquially as GPS) enable anyone with a handheld receiver to determine her location to within a few meters. GPS locators are increasingly included in in-car direction services and allow car-share services like Zipcar to locate their cars. GPS-based systems are used by civilians and the military for navigation on land, sea, and air, and are crucial in situations like a ship making a difficult course in a harbor in bad weather or troops lost in unfamiliar territory, where other navigation tools may not exist. 
 
 
Business & Finance AND Satellites
 
Communications satellites have the ability to rapidly communicate between a number of widely dispersed locations. This is an important tool, allowing big manufacturing companies and department stores to perform inventory management, provide instant credit card authorization and automated teller banking services to even small towns, pay-at-the-pump gas at freeway gas stations, and video conferencing for international corporations.
 
Weather And Satellites
 
Satellites provide meteorologists with the ability to see weather on a global scale, allowing them to follow the effects of phenomena like volcanic eruptions and burning gas and oil fields, to the development of large systems like hurricanes and El Niño. 
 
Climate and Environmental Monitoring Using Satellites
 
Satellites are some of the best sources of data for climate change research. Satellites monitor ocean temperatures and prevailing currents; data acquired by satellite-borne radars were able to show sea levels have been rising by three mm a year over the last decade. Imaging satellites can measure the changing sizes of glaciers, which is difficult to do from the ground due to the remoteness and darkness of the polar regions. Satellites can determine long-term patterns of rainfall, vegetation cover, and emissions of greenhouse gases.
 
Safety And Satellites
Earth observation satellites can monitor ocean and wind currents as well as the extent of forest fires, oil spills, and airborne pollution; together this information helps organize emergency responders and environmental cleanup. Satellites can take the "search" out of "search and rescue" for people in distress in remote regions. Distress radio beacons directly linked to a search and rescue satellite can lead rescuers quickly and accurately to a land, sea, or air emergency location.
 
Land Stewardship And Satellites
 
 
Satellites can detect underground water and mineral sources; monitor the transfer of nutrients and contaminants from land into waterways; and measure land and water temperatures, the growth of algae in seas, and the erosion of topsoil from land. They can efficiently monitor large-scale infrastructure, for example fuel pipelines that need to be checked for leaks, which would require enormous hours of land- or air-based inspection. Imaging satellites produce high-resolution data of almost the entire landmass on earth; such data used to be a closely guarded military capability, but now, nearly anyone with an internet connection can find his house using Google Earth.
 
Development And Satellite
 
Satellites are increasingly important to the developing world. For a country like India, with populations separated by rough terrain and different languages, communications satellites provides remote populations access to education and to medical expertise that would otherwise not reach them. Earth observation satellites also allow developing countries to practice informed resource management and relief agencies to follow refugee population migrations.

Space Science And Satellites

Before the Space Age, astrophysicists were limited to studying the universe via ground-based telescopes, and so could only use information from the parts of the electromagnetic spectrum that penetrated the Earth's atmosphere. Many of the most interesting phenomena are best studied at frequencies that are best or only accessible from space—satellite telescopes have been critical to understanding phenomena like pulsars and black holes as well as measuring the age of the universe. The Hubble Space Telescope is arguably the most valuable astronomical tool ever built.

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General

posted 10 months 3 weeks ago

The James Webb Space Telescope (JWST), previously known as Next Generation Space Telescope (NGST), is a Flagship-class space observatory under construction and scheduled to launch in October 2018. The JWST will offer unprecedented resolution and sensitivity from long-wavelength (orange-red) visible light, through near-infrared to the mid-infrared (0.6 to 27 micrometers), and is a successor instrument to the Hubble Space Telescope and the Spitzer Space Telescope. While Hubble has a 2.4-meter (7.9 ft) mirror, the JWST features a larger and segmented 6.5-meter (21 ft) diameter primary mirror and will be located near the Earth–Sun L2 point. A large sunshield will keep its mirror and four science instruments below 50 K (−220 °C; −370 °F).
 
JWST's capabilities will enable a broad range of investigations across the fields of astronomy and cosmology.One particular goal involves observing some of the most distant events and objects in the Universe, such as the formation of the first galaxies. These types of targets are beyond the reach of current ground and space-based instruments. Another goal is understanding the formation of stars and planets. This will include direct imaging of exoplanets.
 
In gestation since 1996,the project represents an international collaboration of about 17 countries led by NASA, and with significant contributions from the European Space Agency and the Canadian Space Agency. It is named after James E. Webb, the second administrator of NASA, who played an integral role in the Apollo program.
 
The JWST has a history of major cost overruns and delays. The first realistic budget estimates were that the observatory would cost $1.6 billion and launch in 2011. NASA has now scheduled the telescope for a 2018 launch. In 2011, the United States House of Representatives voted to terminate funding, after about $3 billion had been spent and 75% of its hardware was in production.Funding was restored and capped at $8 billion.As of winter 2015–2016, the telescope remained on schedule for an October 2018 launch and within the 2011 revised budget.
 
 
 
The JWST originated in 1996 as the Next Generation Space Telescope (NGST). In 2002 it was renamed after NASA's second administrator (1961–1968) James E. Webb (1906–1992), noted for playing a key role in the Apollo program and establishing scientific research as a core NASA activity.The JWST is a project of the National Aeronautics and Space Administration, the United States space agency, with international collaboration from the European Space Agency and the Canadian Space Agency.
 
The telescope has an expected mass about half of Hubble Space Telescope's, but its primary mirror (a 6.5 meter diameter gold-coated beryllium reflector) will have a collecting area about five times as large (25 m2 vs. 4.5 m2). The JWST is oriented towards near-infrared astronomy, but can also see orange and red visible light, as well as the mid-infrared region, depending on the instrument. The design emphasizes the near to mid-infrared for three main reasons: high-redshift objects have their visible emissions shifted into the infrared, cold objects such as debris disks and planets emit most strongly in the infrared, and this band is difficult to study from the ground or by existing space telescopes such as Hubble.
 
The JWST will operate near the Earth-Sun L2 (Lagrange) point, approximately 1,500,000 km (930,000 mi) beyond the Earth. By way of comparison, Hubble orbits 340 miles (550 km) above the earth's surface, and the Moon is roughly 250,000 miles (400,000 km) from Earth. This distance makes post-launch repair or upgrade of the JWST hardware virtually impossible. Objects near this point can orbit the Sun in synchrony with the Earth, allowing the telescope to remain at a roughly constant distance and use a single sunshield to block heat and light from the Sun and Earth. This will keep the temperature of the spacecraft below 50 K (−220 °C; −370 °F), necessary for infrared observations.
 
Launch is scheduled for October 2018 on an Ariane 5 rocket. Its nominal mission time is five years, with a goal of ten years.The prime contractor is Northrop Grumman.
 
Objective of Making this Telescope
 
The JWST's primary scientific mission has four key goals: to search for light from the first stars and galaxies that formed in the Universe after the Big Bang, to study the formation and evolution of galaxies, to understand the formation of stars and planetary systems and to study planetary systems and the origins of life.These goals can be accomplished more effectively by observation in near-infrared light rather than light in the visible part of the spectrum. For this reason the JWST's instruments will not measure visible or ultraviolet light like the Hubble Telescope, but will have a much greater capacity to perform infrared astronomy. The JWST will be sensitive to a range of wavelengths from 0.6 (orange light) to 28 micrometers (deep infrared radiation at about 100 K (−170 °C; −280 °F)).
 
One of the early and more pressing goals of the JWST will be to gather enough information in order to answer which theory is correct out of the few theories that remain behind the phenomenon of the dimming light of star KIC 8462852.
 
Orbit
The JWST will be located near the second Lagrange point (L2) of the Earth-Sun system, which is 1,500,000 kilometers (930,000 mi) from Earth, directly opposite to the Sun. Normally an object circling the Sun farther out than Earth would take longer than one year to complete its orbit, but near the L2 point the combined gravitational pull of the Earth and the Sun allow a spacecraft to orbit the Sun in the same time it takes the Earth. The telescope will circle about the L2 point in a halo orbit, which will be inclined with respect to the ecliptic, have a radius of approximately 800,000 kilometers (500,000 mi), and take about half a year to complete.Since L2 is just an equilibrium point with no gravitational pull, a halo orbit is not an orbit in the usual sense: the spacecraft is actually in orbit around the Sun, and the halo orbit can be thought of as controlled drifting to remain in the vicinity of the L2 point.This requires some station-keeping: around 2–4 m/s per year from the total budget of 150 m/s.Two sets of thrusters comprise the observatory's propulsion system.
 
Infrared astronomy
JWST is the formal successor to the Hubble Space Telescope (HST), and since its primary emphasis is on infrared observation, it is also a successor to the Spitzer Space Telescope. JWST will far surpass both those telescopes, being able to see many more and much older stars and galaxies.Observing in the infrared is a key technique for achieving this, because it better penetrates obscuring dust and gas, allows observation of dim cooler objects, and because of cosmological redshift. Since water vapor and carbon dioxide in the Earth's atmosphere strongly absorbs most infrared, ground-based infrared astronomy is limited to narrow wavelength ranges where the atmosphere absorbs less strongly. Additionally, the atmosphere itself radiates in the infrared, often overwhelming light from the object being observed. This makes space the ideal place for infrared observation.
 
The distant universe: The more distant an object is, the younger it appears: its light has taken longer to reach human observers. Because the universe is expanding, as the light travels it becomes red-shifted, and these objects are therefore easier to see if viewed in the infrared.JWST's infrared capabilities are expected to let it see all the way to the very first galaxies forming just a few hundred million years after the Big Bang.
 
Dust penetration: Infrared radiation is better able to pass freely through regions of cosmic dust that scatter radiation in the visible spectrum. These two images of the Carina Nebula (right margin) were taken with the HST. The top image was photographed utilizing the visible spectrum whereas the bottom image was taken in the infrared using the HST's WFC3 upgrade. Many more stars can be counted in the infrared image than in the visible light image. Observations in infrared allow the study of objects and regions of space which would be obscured by gas and dust in the visible spectrum,such as the molecular clouds where stars are born, the circumstellar disks that give rise to planets, and the cores of active galaxies.
 
Cool objects: Relatively cool objects (temperatures less than several thousand degrees) emit their radiation primarily in the infrared, as described by Planck's law. As a result, most objects that are cooler than stars are better studied in the infrared. This includes the clouds of the interstellar medium, the "failed stars" called brown dwarfs, planets both in our own and other solar systems, comets and Kuiper belt objects.
 

Ground support and operations

The Space Telescope Science Institute (STScI), located in Baltimore, Maryland on the Homewood campus of Johns Hopkins University, has been selected as the Science and Operations Center (S&OC) for JWST. In this capacity, STScI will be responsible for the scientific operation of the telescope and delivery of data products to the astronomical community.Data will be transmitted from JWST to the ground via NASA's Deep Space Network, processed and calibrated at STScI, and then distributed online to astronomers worldwide. Similar to how Hubble is operated, anyone, anywhere in the world, will be allowed to submit proposals for observations. Each year several committees of astronomers will peer review the submitted proposals to select the programs to observe in the coming year. The authors of the chosen proposals will typically have one year of private access to the new observations, after which the data will become publicly available for download by anyone from the online archive at STScI.
 
Most of the data processing on the telescope is done by conventional single-board computers.The conversion of the analog science data to digital form is performed by the custom-built SIDECAR ASIC (System for Image Digitization, Enhancement, Control And Retrieval Application Specific Integrated Circuit). NASA stated that the SIDECAR ASIC will include all the functions of a 9 kg (20 lb) instrument box in a 3 cm package and consume only 11 milliwatts of power.Since this conversion must be done close to the detectors, on the cool side of the telescope, the low power use of this IC will be crucial for maintaining the low temperature required for optimal operation of the JWST.
 

 

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General

posted 10 months 3 weeks ago

The human eye belongs to a general group of eyes found in nature called "camera-type eyes." Just as a camera lens focuses light onto film, a structure in the eye called the cornea focuses light onto a light-sensitive membrane called the retina.

Structure of the eye

The cornea is a transparent structure found in the very front of the eye that helps to focus incoming light. Situated behind the pupil is a colorless, transparent structure called the crystalline lens. A clear fluid called the aqueous humor fills the space between the cornea and the iris.

"The cornea focuses most of the light, then it passes through the lens, which continues to focus the light," explained Dr. Mark Fromer, an ophthalmologist and retina specialist at Lenox Hill Hospital in New York City.

Behind the cornea is a colored, ring-shaped membrane called the iris. The iris has an adjustable circular opening called the pupil, which can expand or contract to control the amount of light entering the eye, Fromer said.
 
Ciliary muscles surround the lens. The muscles hold the lens in place but they also play an important role in vision. When the muscles relax, they pull on and flatten the lens, allowing the eye to see objects that are far away. To see closer objects clearly, the ciliary muscle must contract in order to thicken the lens.
 
The interior chamber of the eyeball is filled with a jelly-like tissue called the vitreous humor. After passing through the lens, light must travel through this humor before striking the sensitive layer of cells called the retina.
 
 
The retina
Fromer explained that the retina is the innermost of three tissue layers that make up the eye. The outermost layer, called the sclera, is what gives most of the eyeball its white color. The cornea is also a part of the outer layer.
The middle layer between the retina and sclera is called the choroid. The choroid contains blood vessels that supply the retina with nutrients and oxygen and remove its waste products. 
Embedded in the retina are millions of light sensitive cells, which come in two main varieties: rods and cones.
 
Rods are used for monochrome vision in poor light, while cones are used for color and for the detection of fine detail. Cones are packed into a part of the retina directly behind the retina called the fovea, which is responsible for sharp central vision.
 
When light strikes either the rods or the cones of the retina, it's converted into an electric signal that is relayed to the brain via the optic nerve. The brain then translates the electrical signals into the images a person sees, Fromer said.
 
Corneal Layers
 
 
Although appearing to be one clear membrane, the cornea is composed of five distinct layers of tissue, each with its own function.
Epithelium is the thin outermost layer of fast-growing and easily-regenerated cells.
Bowman’s layer consists of irregularly-arranged collagen fibers and protects the corneal stroma. It is 8 to 14 microns thick.
Stroma, the transparent middle and thickest layer of the cornea is made up of regularly-arranged collagen fibers and keratocytes (specialized cells that secrete the collagen and proteoglycans needed to maintain the clarity and curvature of the cornea)
Descemet’s membrane is a thin layer that serves as the modified basement membrane of the corneal endothelium.
Endothelium is a single layer of cells responsible for maintaining proper fluid balance between the aqueous and corneal stromal compartments keeping the cornea transparent.
 
 
 
Vision problems/diseases
The most common problems with vision are nearsightedness (myopia), farsightedness, (hyperopia), a defect in the eye caused by nonspherical curvature (astigmatism) and age-related farsightedness (presbyopia), according to the National Eye Institute.
Most people will develop presbyopia in their 40s or 50s, and start needing reading glasses, Fromer said. With age, the lens gets denser, making it harder for the ciliary muscles to bend the lens, he said. 
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General

posted 10 months 3 weeks ago

The world loves its cell phones  – so much so that there are more cell phones on this planet than people! While these technological devices can offer incredible service and ease in a hectic, modern world, they can also be a serious health hazard.
Cell phones emit radiofrequency energy, a form of non-ionizing radiation. Our bodies absorb this radiation and have a difficult time processing it – leading to numerous bodily complications. One study found that 10 years of cellphone use resulted in an average 290% increased risk of brain tumor development. Interestingly, the tumor development was found on the side of the head in which the cellphone was most used.
And while everyone’s soft tissues are especially (negatively) affected by cell phone use, due to developing organs, lower bone density of the skull, lower body weight, and a less effective blood brain barrier, children are very vulnerable to cell phone radiation.
It is easy to see why protecting yourself from cell phone radiation is more important than ever. Below are 10 tips for reducing exposure.
 
Protecting Against Radiation
 
1. Use the speakerphone on your cell phone when you can have a public conversation, or hook your cell phone up to an earphone or headphones to keep it as far from you as possible while still talking on it.
 
2. Keep your phone charged up. When the bars are low on your cell phone it is working harder to capture a signal from the radio towers, which means that the radiation it emits is even greater. Only make calls when your signal is strong. Consider texting when you can’t charge your phone.
 
3. Text instead of talk. This pings the cell phone towers for seconds rather than minutes and minimizes your radiation exposure.
 
 
4. Don’t talk while you drive. The constant movement means that your phone is also trying to make contact with cell phone towers over and over again, increasing its frequency, and therefore your radiation exposure. But you shouldn’t text while you drive either – so don’t do anything while driving!
 
5. Look for low–radiation emitting phones. There is a list of the 20 best phones for low-radiation emissions, here. The Samsung Galaxy Note is at the top of the list – sorry iPhone users!
 
6. Go old school. Use a landline. If you are under the age of 20, you might scoff at this suggestion, but landlines don’t expose you to radiation. Wait to talk to your BF at your grandmother’s house on her old wall phone. Your brain will thank you.
 
7. Don’t put the cell phone to your ear until a call connects. Dial on speaker phone and then if you must talk straight into the phone, only talk once your end-user picks up.
 
8. Minimize use. Talk less on your phone and you will be exposed to less radiation. I know this is difficult for some of us, but when you can have your conversations in person. I recently took a vacation for an entire week and couldn’t use my cell phone at all. After the first day I had technology withdrawal since I was so used to having a phone in my hand, but after that, it was remarkably peaceful not to have to respond to every little thing within minutes.
 
9. Keep your cell phone far away from you while sleeping or simply not using your cell phone. There is no reason for it to be close to you if you aren’t using it unless you’re expecting a call – especially if you keep it on sound, not vibrate.
 
10. Lastly, consider investing in some form of radiation protection. There are tons of products out there, such as Global Healing Center’s cell phone radiation protector. You can also protect yourself from radiation in your home by placing a large electromagnetic field protector in the area.
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General

posted 10 months 4 weeks ago
ISRO successfully launched a GSLV-MkII rocket on September 8, at 4.50 pm, from the second launchpad at its spaceport in Sriharikota. The rocket carried the INSAT-3DR satellite to a geostationary transfer orbit around Earth. The mission designation was F05.
 
Here’s all you need to know about why this launch was an important occasion for the Indian space programme.
 
The launch was ISRO’s fourth using an indigenous cryogenic engine
 
The first test-flight of the GSLV with a cryogenic upper, or third, stage happened in April 2001. It was a failure. After that, eight flights of the rocket have happened over the next 14 years years. Of these, five flew with a Russian cryogenic engine onboard while the other three used the indigenously developed ones. Three succeeded, four failed and one was a partial success. The first successful test-flight using the Russian engine happened in May 2003. The first successful test-flight using the indigenous engine happened in January 2014.
 
The launch was the first time an indigenous cryogenic engine was used on an operational flight
 
 
An operational flight means ISRO will not be testing any components, flight parameters or flight routes. The launch will solely be about the mission: delivering the payload.
 
ISRO planned to develop a cryogenic engine for use in its rockets in 1986. In the next three years, three different entities from around the world offered to help develop these engines as well as train personnel to work with them. ISRO accepted only the third offer, from a company called Glavkosmos in the erstwhile Soviet Union, because the first two (from the US and France) were unaffordable. However, a paranoid US government imposed sanctions on India and Russia after ISRO and the Russian company refused to call their deal off upon American insistence. The most important effect of this was the Boris Yeltsin government in Russia pressuring Glavkosmos to call off its partnership immediately.
 
As a result, ISRO had to find its own way in the dark. The silver lining was that the company had supplied the organisation with seven cryogenic engines and one mock-up for testing at some additional cost. The indigenous engines that came later were built at the Liquid Propulsion Systems Centre, headquartered in Thiruvananthapuram. And for all the trouble it has been to build and operate, the cryogenic engine allows the GSLV to lift upwards of 1,500 kg to the geostationary transfer orbit. The PSLV rocket cannot reach this orbit with anything heavier than 1,400 kg.
 
The INSAT-3DR satellite will follow up after the INSAT-3D

The INSAT-3DR satellite continues the mission of the INSAT-3D satellite, which was launched in 2013. Both of them belong to the larger class of meteorological satellites operated by ISRO, which includes the KALPANA-1 and the INSAT-3A. KALPANA-1, INSAT-3A and INSAT-3D are in the geostationary orbit. The F05 mission on September 8 will see the GSLV-MkII launch the INSAT-3DR into the geostationary transfer orbit. From there, the satellite will use its built-in propulsion systems to manoeuvre into its eventual geosynchronous orbit.

 
The launch mass of the satellite is 2,211 kg. Of this, 1,255 kg is in propellants.
 
The INSAT-3D satellite was an improvement from its two predecessors because it possessed an atmospheric sounding system. This allowed it to map vertical changes of humidity, temperature and ozone content in Earth’s atmosphere. The INSAT-3DR will be capable of making the same measurements – as well as better image night-time clouds, and better measure sea surface temperature. And like 3D, the 3DR will also include a search-and-rescue transponder, used to pinpoint the location of distressed vessels at sea.
 
The 3D will operate until 2021. The 3DR will last till around 2024. A second successor, INSAT-3DS, is expected to operate from 2022 to 2029. The 3B and 3C are not operational.
 
 
 
A successful launch will have ISRO engineers more confident about the GSLV-MkIII
 
The GSLV is of three kinds: Mk-I, Mk-II and Mk-III. All three have a solid-fuel first stage and a liquid-fuel second stage. The Mk-I uses cryogenic engines of Russian make for the third stage. The Mk-II uses four liquid-fuel strap-on boosters in addition to the first stage and the CE-7.5 indigenous cryogenic engine for the third. The Mk-III will use two solid-fuel boosters for the first stage and the CE-20 indigenous cryogenic engine for the third. The first developmental flight of the Mk-III is expected to happen in December 2016, when it will also carry the 3.2-ton GSAT 19 satellite. A flight in December 2014 had only two functional stages – the CE-20 engine to be used on it had been under development.
 
The F05 mission on September 8 assumes additional significance when the Mk-III test-flight is moved into its backdrop. The Mk-II can lift payloads weighing 2,500 kg to the geostationary transfer orbit. Anything heavier and ISRO has to enlist the services of the French company Arianespace and its Ariane rocket. Specifically, the Ariane 6 can lift 6.5 tonnes to the geostationary transfer orbit. Every time ISRO uses an Ariane 6, the cost is about $95 million. Given that an Mk-II launch costs about $35-40 million, an Mk-III launch that costs between $40 million and $95 million will be also be more economical for ISRO. This benefit is sweetened by the fact that the global satellite-launching industry is estimated to be worth over $300 billion. However, it must be noted that once the Mk-III is ready, its payload capacity of around 4,000 kg to the geostationary transfer orbit will place it in direct competition against SpaceX’s Falcon 9 rocket. Each Falcon 9 launch costs around $62 million.
 
But the more symbolic importance is this: once the Mk-III is ready, it will make ISRO self-sufficient in terms of launch capabilities.
 
It only bodes well that the last two flights of the Mk-II, using the CE-7.5 engines, have both been successful. And now that the F05 mission was also successful, ISRO engineers can proceed with confidence about the prospects of the CE-20 engine*. After all, once it is fully operational and the Mk-III has established itself as reliable after multiple successful flights through 2017, the rocket will eventually be used to carry Indian astronauts to space.
 
Cryogenic tribulations
 
 
The cryogenic engine is troublesome because of how it operates. One way to classify rocket fuel is as solid, liquid and gaseous. Solid fuels don’t flow but release more energy than liquid fuels. Liquid fuels do flow and release more energy than gaseous fuels. Gaseous fuels are harder to contain and don’t flow. But on the flipside, they also boast a star-performer. When hydrogen burns in the presence of oxygen, the resulting change in momentum per unit of fuel combusted is at least 30% higher than that delivered by most other practicable rocket fuels. And this is the chemical reaction that a cryogenic engine facilitates; the ‘cryogenic’ tag comes from the fact that hydrogen and oxygen are both cooled to cryogenic temperatures so that they become liquids and start flowing.
 
Easier said than done, as usual. The gases are liquefied by cooling them: hydrogen to -253.15º C and oxygen to -184.15º C. Because hydrogen’s density is so low, storing sufficient quantities of it requires extremely large containers. And the gases are transported in specially sealed tanks. Their loading onto the rocket is done with extra care, and go through pre-pressurisation and pressurisation phases to keep the liquids from vaporising. Normal pumps can’t move them to the engine’s combustion chamber – that requires specifically designed turbopumps. All containers have to be free of any moisture; the transport passages have to be maintained at low temperatures; special igniters have to be used to light them up; and the onboard computer has to prevent the reaction from going off too soon.

 

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General

posted 11 months 1 week ago
combination of two or more antenna to givr a better directivity in a desired direction are called array antenna they are broadly classified in four category 1.broadside array 2.endfire array 3.collinear(vertical and horizontal) 4.parastic antenna(yadi uda antenna) yagi antenna is also kwon as super directivity antenna as it is having more directivity than other antenna per unit area yagi antenna is named after its founder . defination for yagi antenna is simple dipole or corrugated dipole antenna having one driven element serving as a feed to other parastic elements(reflector and director). basic properties of yagi antenna is 1.it is called beam antenna if it contain array pf three elements(director, driven element,reflector) 2.it has an unidirectional beam with a moderate directivity,low weight, low in cost and simplicty in feed design. 3. we can obtain a bandwith of 2 percent by adjustin the distance 0.25 to 0.5 lambda. 4. it has a gain of 8 db or front to back ratio of 20 db. 5. it is also called super gain antenna as it has more gain from other antenna per unit area(super directivity) 6.more elements are used for more gain but upto a certain limit after which it starts giving narrow beamwidth yagi antenna are used in televisions How to find length of director,driven element and reflector if the operating frequency is given ,then calculate lambda driven element would have a length of lambda by two director length would be 5 percent less.. that is 95 percent of lambda by two reflector length would be 5 percent more than that of 105 percent more than driven element if the frequency is given in mhz and the length of reflector,driven elemnts and director is to be found then use the formula reflector length 500/f(mhz) driven element if 475/f (mhz) director element 455/f(mhz) directivity of endfire antenna is given by D= 4n(d/lambda) where small d represent spacing between two elements gain in general is given by 4.5 A/(lambda square) where a represents the area.
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