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Google is looking for people [18+] from across the globe to help the
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You
can participate in the User Experience Research study by either
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You will get paid depending on the type of study, but
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Related: Work from Home for Google - all you need is a bachelor's degree and a high-speed internet connection to telecommute.
By Subir Bhaumik BBC News, Calcutta |
Rebels in India's north-eastern state of Tripura are making pornographic films to raise money for their separatist campaign, officials say.
The information has come from surrendered guerrillas of the National Liberation Front of Tripura (NLFT), according to police.
They say the rebels are forcing captured tribal women, and some men, to take part in the films.
The films are then dubbed to be sold in India and neighbouring countries.
Remote areas
The former guerrillas of the NLFT have told police their leaders not only sexually abused scores of tribal girls recruited into the rebel army but also used them - and some male guerrillas - to produce scores of porn films, officials say.
"The films were found to be dubbed in Burmese, Bengali, Thai and Hindi, suggesting they were being marketed to many countries in the region," said Ghanshyam Murari Srivastava, Tripura's police chief.
He said police have recovered scores of pornographic DVDs featuring young women and men from various parts of the state, including remote areas such as Amarpur and Gandacherra.
Such pornographic DVDs have also been recovered from NLFT bases inside Bangladesh after they were raided by the Bangladesh army, the police chief said.
'Sleek product'
Discreet inquiries with video production houses in Tripura confirmed what the surrendered rebels are reported to have said.
"We do get orders to process raw porn shot in remote tribal areas from time to time," the owner of a video production company in the state's capital Agartala told the BBC.
He did not want to be named.
"We get a lot more money , much above our normal rates, to process these films and deliver a sleek final product.
"We know the insurgents are behind these films. When we process their raw stock, we can see boys standing around with automatic rifles and revolvers pulling in girls but we are supposed to cut all that out and just concentrate on the sex," the owner said.
"It is very good money and we don't think it is right to question the insurgents anyway," he said.
The latest pornographic video that has become sought after by young men in Tripura is Hamjagoi Tongthoklaima, or Our Experiences.
Like a feature film, it runs a full cast of "heroes" and "heroines".
Initially it appears to be a love film with boys and girls holding hands and walking past lakes and trees. But soon the video starts featuring close-up shots of the actors undressing and sex.
'Actress fled'
Surrendered NLFT rebels say their leaders have always abused tribal women , both in the villages and also those recruited into the rebel army.
A study by two researchers, Meenakshi Sen Bandopadhyay and Jayanta Bhattacharya, documented in detail sexual abuses perpetrated by the NLFT.
"The NLFT rebels did not allow a tribal girl in North Tripura to get married because they wanted to enjoy her by turns. Her parents were helpless because they lived in a tea garden in a remote area," the study says.
One surrendered NLFT guerrilla Mohan Reang said: "One tribal actress Anita Reang who played the heroine in some local films had to flee her village because a top NLFT leader wanted to whisk her away."
But while forcing tribal women to have sex with them at gunpoint or carrying them away to the rebel camps is not new, using them to produce pornography certainly is.
"This seems to have started a year or two back," says local journalist Manas Paul who began legal proceedings to bring this to the notice of the authorities.
"But it is now rampant, so many of these discs are circulating all over our state and possibly in other parts of northeast India as well," he said.
But in some other northeast Indian states like Manipur, the rebels punish those who produce pornography.
In the state of Manipur, some girls who acted in porn films were shot in the legs, as were the producers.
The man tells Al, one of his workers, that he will name the resaurant after the first thing Al sees when he goes out the door.
Al walks outside and the first thing he saw was a girl named Lucy and he saw her legs. He told the man, and so the restaurant was named Lucy's Legs. The man was so impressed that he said the next day Al could get a free drink.
The next day Al comes a bit early and a policeman walks by and notices Al waiting there. The policeman asks, "What are you doing?"
Al says, "I'm waiting for Lucy's legs to open so I can get a drink."
Paragliding (known in some countries as parapenting) is a recreational and competitive flying sport. A paraglider is a free-flying, foot-launched aircraft. The pilot sits in a harness suspended below a fabric wing, whose shape is formed by the pressure of air entering vents in the front of the wing.
It is closely related to hang gliding, but quite different from parasailing/parascending, which don't involve free flight. Paramotoring uses the same equipment, with the addition of a propeller mounted behind the pilot, making it a form of ultra-light aviation as opposed to free flight.
The paraglider wing (or ‘canopy’ or parafoil) is a self-inflating structure consisting of a row of cells, most of them open at the front and all of them closed at the back, joined together side by side. Moving through the air keeps them inflated as air enters in the front but can't get out the back. In cross-section, the cells form an aerofoil shape to produce lift, just like an airplane wing.
The pilot is supported underneath the wing from a web of lines (each with the strength to support the pilot). The lines are then attached to strap-like risers that are attached to the pilot's harness.
Controls held in the pilot’s hands, which pull down the trailing edge of the wing, are used to control speed and to turn.
The pilot is strapped into the bucket-seat harness, which usually holds a reserve parachute, and includes a ‘speed system’ which pulls down the leading edge for maximum flying speed. Modern recreational harnesses have a foam or air-bag back protector.
Paraglider wings typically have an area of 20–30 m² with a span of 8–12 m, and weigh 3–7 kg. Combined weight of wing, harness, reserve, instruments, etc is around 12–16 kg.
Glide ratio ranges from 6:1 for recreational paragliders to about 10:1 for modern competition paragliders (compared with an average of 15:1 for hang gliders and up to 60:1 for some sailplanes), and speed range is typically 20–65 km/h (stall speed – max speed): though safe flying range is smaller.
Modern paraglider wings are made of high-performance non-porous fabrics such as Porcher Marine & Gelvenor, with Dyneema/Spectra or Kevlar/Aramid lines.
For storage and carrying, the wing is folded into the harness seat, and the whole stored in a backpack (which is normally stowed in the harness in flight).
Tandem paragliders, designed to carry the pilot and one passenger, are larger but otherwise similar. They usually have higher trim speeds, are more resistant to collapses and have a slightly higher sink rate compared to solo paragliders.
Parachutes are generally used for descending purposes (i.e. jumping out of an aircraft) while paragliders are generally used for ascending. Paragliders are categorized as "ascending" parachutes by canopy manufacutures worldwide and involve "free flying" (without a tether) or an aircraft.
In unpowered flight, rising air is needed to keep a glider aloft. This rising air can come from two sources:
In mountainous environments, flying is mostly based around thermals, which can be used to stay aloft before heading for a landing field below the launch site. In hill environments, ridge lift is used for ridge soaring, and landing can be done either back at the launch site, or at a landing field at the bottom of the ridge. In either case, more experienced pilots can use thermals to go ‘cross country’.
In ridge soaring, pilots fly along the length of a ridge feature in the landscape, relying on the lift provided by the air which is forced up as it passes over the ridge.
Ridge soaring is highly dependent on a steady wind within a defined range (the suitable range depends on the performance of the wing and the skill of the pilot). Too little wind, and insufficient lift is available to stay airborne (pilots end up ‘scratching’ along the slope). With more wind, gliders can fly well above and forward of the ridge, but too much wind, and there is a risk of being ‘blown back’ over the ridge.
When ridge soaring, it is usually possible to either ‘top land’ or ‘slope land’ close to the launch site, which saves time returning from a landing site back to the launch site.
When the sun warms the ground, it will warm some features more than others (such as rock-faces or large buildings), and these set off thermals which rise through the air. Sometimes these may be a simple rising column of air; more often, they are blown sideways in the wind, and will break off from the source, with a new thermal forming later.
Once a pilot finds a thermal, he or she begins to fly in a circle, trying to center the circle on the strongest part of the thermal (the "core"), where the air is rising the fastest. Most pilots use a ‘vario’ (vario-altimeter), which indicates climb rate with beeps and/or a visual display, to help ‘core-in’ on a thermal.
Coring: The technique to "core" a thermal is simple: turn tighter as lift decreases, and turn less as lift increases. This ensures you are always flying around the core.
Often there is strong sink surrounding thermals, and there is often also strong turbulence resulting in wing collapses as a pilot tries to enter a strong thermal. Once inside a thermal, shear forces reduce somewhat and the lift tends to become smoother.
Good thermal flying is a skill which takes time to learn, but a good pilot can often "core" a thermal all the way to cloud base.
Once the skills of using thermals to gain altitude have been mastered, pilots can glide from one thermal to the next to go ‘cross-country’ (‘XC’). Having gained altitude in a thermal, a pilot glides down to the next available thermal. Potential thermals can be identified by land features which typically generate thermals, or by cumulus clouds which mark the top of a rising column of warm, humid air as it reaches the dew point and condenses to form a cloud. In many flying areas, cross-country pilots also need an intimate familiarity with air law, flying regulations, aviation maps indicating restricted airspace, etc.
As with all aircraft, launching and landing are done into wind (though in mountain flying, it is possible to launch in nil wind and glide out to the first thermal).
In low winds, the wing is inflated with a ‘forward launch’, where the pilot runs forward so that the air pressure generated by the forward movement inflates the wing. In higher winds, particularly ridge soaring, a ‘reverse launch’ is used, with the pilot facing the wing to bring it up into a flying position, then turning under the wing to launch.
In flatter countryside, pilots can also be launched with a tow. Once at full height, the pilot pulls a release cord and the towline falls away. This requires separate training, as flying on a winch has quite different characteristics from free flying. In many countries only towing from a stationary winch is permitted: ‘static’ towing, with a fixed length towline attached to a car, is far more dangerous.
Landing involves lining up for an approach into wind, and just before touching down, ‘flaring’ the wing to minimise forward speed. The angle of approach to the landing zone will depend on wind speed. Landing will typically be at a gentle forward run.
The pilot holds controls in each hand which pull down the trailing edge of the wing. Pulling down the trailing edge increases the angle of attack of the wing from its ‘trim’ (hands-off) position, which slows it down (like flaps on an aircraft wing). Turning is achieved by a combination of pulling down the control on one side, and ‘weight shift’ within the harness. Faster than ‘trim’ speed can be achieved by pushing out a ‘speedbar’ with the feet, which pulls down the leading edge to reduce the angle of attack.
On occasions when it is necessary to lose height more rapidly, the tips of the wing can be ‘folded in’, in what is known as ‘big ears’. This reduces the flying area of the wing, effectively reducing the glide ratio.
In more extreme conditions, other manoeuvres such as ‘b-line stalls’ and spiral dives can be used, but most pilots avoid getting themselves into situations where these are required.
In turbulent air, since the wing is not rigid, part or all of the wing can collapse. On modern recreational wings, such collapses will normally recover themselves without pilot intervention. For the rare case where it is not possible to recover from a collapse (or from other threatening situations such as a spin), most pilots carry a reserve parachute. Thankfully, most pilots never have cause to ‘throw’ their reserve. In case the collapse happens near ground, i.e. shortly after takeoff or just before landing, the collapse may not recover even with pilot intervention and there will not be enough time for throwing the reserve. In that case serious injury or even accidents resulting in death can occur. Collapses and other hazards are minimized by flying a suitable glider, and choosing appropriate locations and weather conditions, for the pilot's skill and experience.
Some pilots like to stretch themselves beyond recreational flying. For such pilots, there are multiple disciplines available:
Competitive flying is done on high performance wings which demand far more skill to fly than their recreational counterparts, but which are far more responsive and offer greater feedback to the pilot, as well as flying faster with better glide ratios.
See also: FAI World Paragliding Championships, 2005 World Championship, Paragliding World Cup, Red Bull Vertigo Aerobatics World Cup.
Most pilots use varios and radios when flying; some more advanced pilots also use GPS units.
Birds are highly sensitive to atmospheric pressure, and can tell when they are in rising or sinking air. People can sense the acceleration when they first hit a thermal, but cannot detect the difference between constant rising air and constant sinking air, so turn to technology to help.
A vario-altimeter indicates climb-rate (or sink-rate) with audio signals (beeps which increase in pitch and tempo as you accelerate upwards and a droning sound which gets deeper as your decent rate increases) and/or a visual display. It also shows altitude: either above takeoff, above sea level, or (at higher altitudes) ‘flight level’.
The main purpose of a vario is in helping a pilot find and stay in the ‘core’ of a thermal to maximise height gain, and conversely indicating when he or she is in sinking air, and needs to find rising air.
Pilots use radio for training purposes, and for communicating with other pilots in the air – particularly when travelling together on cross-country flights.
Radios used are PTT (push-to-talk) transceivers, normally operating in or around the FM VHF 2-metre band (144–148 MHz). Usually a microphone is incorporated in the helmet, and the PTT switch is either fixed to the outside of the helmet, or strapped to a finger.
GPS(global positioning system) is a necessary accessory when flying competitions, where it has to be demonstrated that way-points have been correctly passed.
It can also be interesting to view a GPS track of a flight when back on the ground, to analyse flying technique. Computer software is available which allows various different analyses of GPS tracks (e.g. CompeGPS).
Other uses include being able to determine drift due to the prevailing wind when flying at altitude, providing position information to allow restricted airspace to be avoided, and identifying one’s location for retrieval teams after landing-out in unfamiliar territory.
More recently, the use of GPS data, linked to a computer, has enabled pilots to share 3D tracks of their flights on Google Earth. This fascinating insight allows comparisons between competing pilots to be made in a detailed 'post-flight' analysis.
Paragliding is perhaps often viewed as a higher-risk sport than it actually is. Nonetheless, there is great potential for injury for the reckless or ill-prepared.
It is sometimes said that the factor which most affects safety is pilot attitude. A large proportion of accidents involve over-confident novices failing to heed advice, or pilots flying beyond their limits – often in a competitive context.
Most pilots will try to stay clear of:
Safety precautions include pre-flight checks, flying helmets, harnesses with back protection (foam or air-bag), a reserve parachute, and careful pre-launch observation of other pilots in the air to evaluate conditions.
For pilots who want to stretch themselves into more challenging conditions, advanced ‘SIV’ (simulation d’incidents de vol, or simulation of flying incidents) courses are available which teach pilots how to cope with hazardous situations which can arise in flight. Through tuition over radio (above a lake), pilots deliberately induce major collapses, stalls, spins, etc, in order to learn procedures for recovering from them. (As mentioned above, modern recreational wings will recover from minor collapses without intervention).
While fatalities do occur, most properly-trained, responsible pilots suffer nothing worse than possible minor injuries – particularly twisted ankles and back injuries – and an occasional pounding heart.
Most popular paragliding regions have a number of schools, generally registered with and/or organized by national associations. Certification systems vary widely between countries, though around 10 days instruction to basic certification is standard.
There are several key components to a paragliding pilot certification instruction program. Initial training for beginning pilots usually begins with some amount of ground school to discuss the basics, including elementary theories of flight as well as basic structure and operation of the paraglider.
Students then learn how to control the glider on the ground, practicing take-offs and controlling the wing 'overhead'. Low, gentle hills are next where students get their first short flights, flying at very low altitudes, to get used to the handling of the wing over varied terrain. Special winches can be used to tow the glider to low altitude in areas that have no hills readily available.
As their skills progress, students move on to steeper/higher hills (or higher winch tows), making longer flights, and learning to turn the glider, control the glider's speed, then moving on to 360° turns, spot landings, ‘big ears’ (used to increase the rate of descent for the paraglider), and other more advanced techniques. Training instruction are often provided to the student via radio, particularly during the first flights.
A third key component to a complete paragliding instructional program provides substantial background in the key areas of meteorology, aerology, aviation law, and general flight area etiquette.
To give prospective pilots a chance to determine if they would like to proceed with a full pilot training program, most schools offer tandem flights, in which an experienced instructor pilots the paraglider with the prospective pilot as a passenger.
The current (as of June 2006) world distance record was set by American David Butcher on 21 June 2002 who flew 513.4 km (276 miles) in 10½ hours from the town of Burlington, Kentucky, United States.
The height gain record was set by Leroy Westercamp of the Netherlands who on September 2006 flew 4,785m (15,698 ft) above takeoff in Pakistan.
Other records can be seen on the FAI site.
In 1954, the prescient Walter Neumark foresaw (in an article in Flight magazine) a time when a glider pilot would be “able to launch himself by running over the edge of a cliff or down a slope … whether on a rock-climbing holiday in Skye or ski-ing in the Alps”.
In 1961, the French engineer Pierre Lemoigne produced improved parachute designs which led to the Para-Commander (‘PC’), which had cut-outs at the rear and sides which enabled it to be towed into the air and steered – leading to parasailing/parascending.
Sometimes credited with the greatest development in parachutes since Leonardo da Vinci, the American Domina Jalbert invented in 1964 a rectangular parafoil which had sectioned cells in an aerofoil shape; an open leading edge and a closed trailing edge, inflated by passage through the air – the so-called ‘ram-air’ design.
Walter Neumark shortly afterwards wrote the wonderfully entitled Operating Procedures for Ascending Parachutes, and he and a group of enthusiasts with a passion for tow-launching ‘PCs’ and ram-air parachutes eventually broke away from the British Parachute Association to form the British Association of Parascending Clubs (BAPC) in 1973.
Meanwhile, David Barish was developing the ‘Sail Wing’ for recovery of NASA space capsules – “slope soaring was a way of testing out … the Sail Wing”. After tests on Hunter Mountain, New York in September 1965, he went on to promote ‘slope soaring’ as a summer activity for ski resorts (apparently without great success).
(NASA probably originated the term ‘paraglider’ in the early 1960’s, and ‘paragliding’ was first used in the early 1970’s to describe foot-launching of gliding parachutes).
These threads were pulled together in June 1978 by three friends Jean-Claude Bétemps, André Bohn and Gérard Bosson from Haute-Savoie, France. After inspiration from an article on ‘slope soaring’ in the Parachute Manual magazine by parachutist & publisher Dan Poynter, they calculated that on a suitable slope, a ‘square’ ram-air parachute could be inflated by running down the slope; Bétemps launched from Pointe du Pertuiset, Mieussy, and flew 100 m. Bohn followed him and glided down to the football pitch in the valley 1000 metres below. ‘Parapente’ (pente being French for slope) was born.
Through the 1980’s and since, it has been a story of constantly improving equipment and ever greater numbers of paragliding pilots. The first World Championship was held in Kössen, Austria in 1989.
Numbers of actively flying plots can only be a rough estimate, but France is reckoned to have the largest number, at around 25 000. Next most active flying countries are Germany, Austria, Switzerland, Japan, and Korea, at around 10 000 – 20 000, followed by Italy, the UK, and Spain with around 5 000 – 10 000. The USA has around 4 500. (All as of 2004).
Paragliding and hang gliding are closely related sports – foot-launched gliders with flexible wings, with options for tow launching and for powered flight – and there is sometimes confusion about the differences.
The main differences between them are:
Paragliders | Hang gliders | |
---|---|---|
Wing structure: | entirely flexible, with shape maintained purely by the pressure of air flowing into the wing in flight and the tension of the lines | supported on a rigid frame which determines its shape |
Pilot position: | sitting ‘supine’ in a seated harness | lying ‘prone’ in a cocoon-like harness suspended from the wing |
Speed range (stall speed – max speed): | slower – hence easier to launch and fly in light winds | faster – hence easier to launch and fly in stronger conditions |
Glide angle: | poorer glide performance makes long-distances more difficult | better glide performance enables longer-distance flying |
Landing-out: | smaller space needed to land, offering more landing options from cross-country flights. Also easier to carry back to the nearest road | longer approach & landing area required, limiting landing options |
Learning: | quicker to get ‘into the air’ with most skills learned in the air; flying tandem with an instructor is rarely necessary during instruction | basic control skills are learned in ground school, and in flights close to the ground prior to high flights; |
Convenience: | pack smaller (easier to transport and store); lighter (easier to carry); quicker to rig & de-rig | more awkward to transport & store; difficult to carry single-handed; longer to rig & de-rig |
Cost: | cheaper but less durable | more expensive but more durable |