From the monthly archives:

August 2009

Hybrid vehicles

by Amartya Ghosh on August 14, 2009

Due to galloping technological development and it’s impact on day to day life of people, it’s effect on the various genres of society has become invincible and so is effect on automotive industry and people directly attached to this massive industry, manufacturers, customers, transport departments etc. Thus day to day increase in no. of vehicles on road is creating two major problems

  • creating pollution endangering people’s life
  • reducing natural resources of earth

To tackle these problems, modern day car makers have come up with the new revolutionary concept named Hybrid, which more no.of car makers are applying day be day. But many people fail to find a reply to the basic question, why a Hybrid, what does it actually mean, is it a kind of vehicle using mixed and impure fuels? Is it actually beneficial? These questions even came to me at one point of time and believe me searching the Internet or inquiring I got nothing but more confused. So I thought of coming up with this brief and simple description of a hybrid vehicle, it’s use, boons and banes.

Any vehicle that combines two or more sources of power that can directly or indirectly provide propulsion power is a hybrid. Most hybrid cars on the road right now are gasoline-electric hybrids, although French car maker PSA Peugeot Citroen has two diesel-electric hybrid cars in the works. In this article my topic of discussion would be limited to gasoline-electric hybrid car which is a cross between a gasoline-powered car and an electric car.

A gas-powered car has a fuel tank, which supplies gasoline to the engine. The engine then turns a transmission, which turn the wheels. Whereas an electric car has a set of batteries that provides electricity to an electric motor. The motor turns a transmission, and the transmission turn the wheels. Performance wise when a gasoline engine can produce         100hp@5000-6000rpm, an electric engine can produce 100Kw(135hp)@15000rpm. Also an electric vehicle transmission has no need of a single gear with such high available motor rpm. But on the other hand consumption in electric vehicles is much higher and refueling is not convenient. So considering the factors that gasoline engine gives us better mileage and economy, but is prone to pollution, and electric vehicle very much anti polluting but less economic, scientists thought of conglomerating the boons of the two into one vehicle to get the best out of it.

Components of a Hybrid car:

  • Gasoline engine: Smaller but more fuel efficient and anti emmisive
  • Fuel tank:              Energy storage device (energy density of gasoline is much higher than batteries)
  • Electric motor:  It acts as a motor as well a generator. It can draw energy from batteries and also return it.
  • Generator:           Produces electric power
  • Batteries:              Energy storage device for electric motor (both to and fro)
  • Transmission :  Same as gasoline engine

Types of hybrid cars:

  1. Parallel hybrid
  2. Series hybrid

1.Parallel hybrid: There is a fuel tank that supplies gasoline to the engine and a battery that supplies power to the motor. Both engine and motor can turn the transmission which as a result turns the wheel.

2.Series hybrid: Here a gasoline engine turns a generator, and the generator can either charge the batteries or power an electric motor that drives the transmission. Thus, the gasoline engine never directly powers the vehicle.

Performance :

In a hybrid car the gasoline engine is much smaller in size and thus more efficient due to less no.of cylinders, less weight , operation neat to maximum load,less fuel consumption,smaller piston strokes. Thus a hybrid car engine with the smaller engine and with the aid of motor can perform as a car with some v6, v8 engine. Genuinely the hybrid car uses the full power range available and uses the peak power too which is hardly found in gasoline engines because of car dangerous vibration and ample heat generation may take place.

Improving fuel economy:

Modern day hybrid cars are even developing in providing a much better fuel economy which is indeed increasing its demand allover.

  • Restoration of energy: Unlike normal vehicle, hybrid vehicles capture the kinetic energy of a moving vehicle during braking and store it in batteries for later usage. It does this by Regenerative braking procedure, i.e. while braking the motor acts as generator and charge the batteries.
  • Engine shut-off: A hybrid vehicle can easily shut off the gasoline service because it has alternative power source through motor and batteries.
  • Other techniques common to normal cars like reducing aerodynamic drag, using light weight metal bodies etc.

Good examples of hybrid cars are Honda Accord hybrid, Honda Civic hybrid, Toyota Prius, Honda Insight. Indian UV giant Mahindra & Mahindra Ltd is also coming up with their hybrid in some time, already launched in Delhi auto expo, 2008.

Benefits of Hybrid car:

  • Reduce tailpipe emission
  • Improve mileage

N.B:  Mahindra Scorpio, Bolero micro-hybrid:

A micro hybrid is not a full hybrid – but in India, it is a pathbreaking technology. A full hybrid switches between petrol engine and an electric motor while driving. A micro hybrid engine, on the other hand, switches off the engine when the vehicle is in neutral gear and restarts it seamlessly when the the vehicle is shifted out of neutral gear.

In heavy traffic in a city, the micro hybrid technology can save a substantial amount of fuel for the Scorpio and Bolero which used the FuelSmart technology. The Micro Hybrid Fuel Smart enabled Scorpio and Bolero shuts down the engine when the vehicle is stationary while in neutral gear or idle after waiting ten seconds. When the vehicle has to move, just depressing the clutch pedal again, the engine restarts seamlessly.

It’s a unique feature in an Indian road vehicle since people are hardly concerned about switching off the engine in traffic signals and jams to reduce pollution. It’s an eye opener to various manufacturers too.

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The Jews of Calcutta

by Dr. Anjan K Das on August 12, 2009

The Maghen David Synagogue

The Maghen David Synagogue

The Ezra Hospital was tucked away along the Colootola road adjacent to the Calcutta University complex. It was of little concern to us as students, as it housed the ENT Department and the Chest Department which consumed very little of our time during those days. However it housed the Students’ Ward as well and here students used to repair occasionally to while away their blues after a rotten examination or a dead love affair. No consultant ever ever dreamt of coming to see you and only the nurses used to check your temperature twice a day. There was ample time for smoking and adda and when you had tired of the pleasures of a sort of solitude, you requested the House Physician to discharge you so that you could go back to the hostel. When we became Interns and House Surgeons, the Ezra Block was known for its quietness and lack of the usual hustle and bustle that was the usual scene in all other wards of the Medical College. , The patients either had had a mastoidectomy or a tonsillectomy and did not need much looking after, or were long term inhabitants of the TB ward. The nurses there thus had lots of leisure to entertain the housemen and many a love affair blossomed in those hallowed premises.

The Ezra Ward was however of historical importance. It was opened in 1887, though one source claims that patients were not admitted in it till the following year. It was the gift of a Jewish lady
Mrs. Mozelle E. D. J. Ezra in memory of her husband who was the king of real estate in the Calcutta of the mid nineteenth century. There used to be a Jewish ward in those days, reserved for Jews, I have seen it in use only once in my days at the College when a young Jewish girl, probably one of the last in Calcutta was admitted for appendicectomy. Her name was perhaps Rebecca. I am not sure about her name, but I clearly do remember that she was extremely pretty. She told me that she was leaving for Canada in a few months time.

The other Jew that all Calcutta knows is of course, David Nahoum, who still runs the Confectionery shop that his grandfather founded in 1874. It is the place where we used to get our birthday cakes and we went there for our children’s cakes as well. The decor and its ambiance has remained the same ever since I can remember, though it has been quite awhile since I was last there. Gama’s where my mother always bought her bread when in New Market, closed down some years ago, probably the last of the family passed away and his heirs were all in Israel.

That has been the story of Calcutta Jews after independence, a flight to Israel or to the West. They however left behind a history dating back to 1790, when Shalom Aaron Copen came to Calcutta from Baghdad and set of the trend of Bagdadi Jews (Iraqi Jews ) settling in Calcutta. They were consummate businessmen and great traders and many of them began to trade in Murshidabad silks and Dacca muslin to the markets of what is now known as the Middle East.

Later members of the community were not above participating in the opium trade to China and in fact any trade that turned in an honest profit. When the opium trade came to a halt following an outcry in England against the rank hypocrisy of a British East Indian Company forcing opium down the throats of an unwilling Chinese population, many of them turned to Real Estate and took over much of the real estate business in the European heart of Calcutta. The community reached its peak in the early twentieth century as they built synagogues, including the Beth El. This was considered to be the most imposing synagogue in the East when it was built in the 1850s and the Maghen David which was built in the Italian style with the pillars being shipped in, it is alleged , from Paris. (see pic, borrowed from Flickr).

The population was always low, not more than 3000 at its peak but it was by all accounts a lively community which formed an important part of the mosaic of Calcutta. Now it is said that less than 10 survive in Calcutta so that the quorum for prayers at the Synagogue is never obtained.
It is sad to think that such a vigorous community does not exist in Calcutta nay more, but when native sons are leaving in droves, what can hold them back in a city of uncertain future?

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