Introduction
Genetic algorithms (GAs) are a powerful tool for global search and optimisation tasks of high complexity in science, technology, industry medicine, safety, economy, communication etc. They are a particular class of evolutionary algorithms, based on the mechanics of natural selection (biological evolution). It was developed by John Holland The idea behind GA’s is Darwinian evolution The most basic concept is the strong tend to adapt and survive while the weak tend to die out. That is, optimization is based on evolution, “Genetic Inheritance” and the "Survival of the fittest" concept. These algorithms employ classical operations (selection, crossover, mutation).
Genetic algorithms (GAs) can be easily modified in order to account for specific features of the given computational problem. Particularly well suited for hard problems where little is known about the underlying search space
Genetic algorithms are best for searching for new solutions and making use of solutions that have worked well in the past. It works on large population of candidate solutions that are repeatedly subjected to selection pressure (survival of the fittest) and which undergo naturally occurring genetic operators in search of improved solutions.
GENETIC ALGORITHMS We use Genetic Algorithms in following situations
When an acceptable solution representation is available
When a good fitness function is available
When it is feasible to evaluate each potential solution
When a near-optimal, but not optimal solution is acceptable.
When the state-space is too large for other methods
Genetic Algorithms vs Traditional Algorithm Genetic algorithms are different in some fundamental ways from the traditional search techniques in the following ways.
GA’s work with a coding of parameter set, not the parameter themselves.
GA’s search from a population of points, not a single point.
Application of GA operators causes information from the previous generation to be carried over to the next.
GA’s use probabilistic rules, not deterministic rules.
BASIC COMPONENTS OF GENETIC ALGORITHMS
GAs are blind without the fitness function.The Fitness Function Drives the Population Toward Better Solutions and is the most important part of the algorithm. Most Important Parameters in GAs:
Population Size
The algorithm is started with a set of solutions (represented by chromosomes) called population.
Fittness Function
Determine the fitness of each member of the populationCrossover Method
Crossover selects genes from parent chromosomes and creates a new offspring
Mutation
This is to prevent fall all solutions in population into a local optimum of solved problem
Reproduction (SELECTION)
Determine which strings are "copied" or "selected" for the mating pool and how many times a string will be "selected" for the mating pool .
GENETIC PROGRAMMING
Manipulate strings of instructions rather than strings of data. Goal: Allow computers to develop their own software
(Survival of the fittest computer programs) Genetic Programming starts with an initial population of randomly generated computer programs composed of functions and terminals appropriate to the problem domain. The functions may be standard arithmetic operations, standard programming operations, standard mathematical functions, logical functions, or domain-specific functions.
ADVANTAGES OF GENETIC ALGORITHMS
The main advantages of genetic algorithms are,
A robust search technique
GAs will produce "close" to optimal results in a
"reasonable" amount of time
Suitable for parallel processing
Some problems are deceptive
Can use a noisy fitness function
Fairly simple to develop
Makes no assumptions about the problem space
APPLICATIONS OF GENETIC ALGORITHMS
The possible applications of genetic algorithms are immense. Any problem that has a large search domain could be suitable tackled by GAs. A popular growing field is genetic programming (GP). Genetic Programming particularly used in machine learning, scientific modeling, and artificial life. Scheduling:
Facility, Production, Job, and Transportation Scheduling.
Design:
Circuit board layout, Communication Network design,keyboard layout, Parametric design in aircraft.
Machine Learning:
Designing Neural Networks, Classifier Systems, Learning rules.
Robotics:
Trajectory Planning, Path planning.
Combinatorial Optimization:
TSP, Bin Packing, Set Covering, Graph Bisection, Routing.
Image Processing:
Pattern recognition.
Business:
Economic Forecasting; Evaluating credit risks.
Detecting stolen credit cards before customer reports it is stolen.
Medical:
Studying health risks for a population exposed to toxins. CONCLUSION
Genetic algorithms (GAs) are a powerful tool for global search and optimisation tasks of high complexity in science, technology, industry medicine, safety, economy, communication etc. They are a particular class of evolutionary algorithms, based on the mechanics of natural selection (biological evolution).
Genetic algorithms (GAs) can be easily modified in order to account for specific features of the given computational problem. Particularly well suited for hard problems where little is known about the underlying search space.
Genetic algorithms are best for searching for new solutions and making use of solutions that have worked well in the past. It works on large population of candidate solutions that are repeatedly subjected to selection pressure (survival of the fittest) and which undergo naturally occurring genetic operators in search of improved solutions.
Sunday, November 16, 2008
Saturday, November 1, 2008
Non - Drug Therapy for Hypertension
NON - DRUG THERAPY FOR HYPERTENSION
1) Weight reduction :- " Excess weight at any age is associated with
more hypertension, apart fom the risk of coronary heart disease".
a) Obesity may also be associated with diabetes.
b) There is an association between diabetes and high blood pressure.
c) Calorie restriction results in a fall in high blood pressure.
d) Whether it is diet restriction plus modified fasting, it should work
without endangering the health of the person.
e) The weight reduction must be slow and steady.
f) In medical term over weight is called obesity.
g) Over weight or obesity occurs in people where food intake
exceeds the energy requirements of the body for physical
activity and growth. As a result, there is accumulation of fat
which is stored in a dispose tissue (fat cells). This storage
may be localised in certain parts of the body.
h) It is proved that harmones from pituitary, thyroid and adernal
glands along with insulin and sex harmones have an important
role in regulating the fat metabolism.
i) In the adults, an increase in body weight may reflect an increase
in fat in a dispose tissue, an accumulation of fluid or both.
j) Weight gain excess of 1kg per day almost invariably implies
excess fluid retentation
k) Caution:- Every one should appreciate that any programme
which results in weight loss more than 0.3 kg per day undoubtedly
represents large amounts fluid loss rather than fat.
The weight reduction must be slow and steady.
A person is considered over weight if he exceeds the upper range of
ideal weight for his body frame. He is considered as obese if his weight
exceeds by 9 to 10 kgs his ideal weight.
m) Caution : - Obesity (Over weight) is the commonest predisposing cause
for the following problems
1) Diabetes Mellitus ( Excessive blood sugar )
2) Hypercholesterolaemia ( High blood cholesterol ).
3) Hypertension ( High blood pressure )
4 ) Ischaemic heart disease ( heart attacks ).
5) Osteoarthritis of weight bearing joints ( Hips, knees and ankles ).
6) Lumbar and Cervical Spondylosis.
7) Varicose veins ( Dilated, tortuous veins in legs).
8) Hernias, particularly incisional hernia, after operations.
9) Galler blader stones.
Diet and exercises are the only methods to attain ideal weight.
2) Avoid Rich food : - Chocolates, softies, ice creams, oily spice foods,
tinned & stored foods( animal fat foods).
Take more fibre and less saturated fat : - Increase in use of unsaturated
fats ( sun flower oil, corn oil) can induce lower blood pressures. Take
high - fibre foods like vegetables, fruits, bran, cereals etc.
3) Restriction of salt (sodium) intake to 1g per day. Avoid permanently
mangoe pickles and other pickles.
4) Stop Smoking permanently : - smoking immediately accelerates heart
rate and shoots up blood pressure which imposes extra burden on the
heart. Heavy smoking The Nicotin in tobacco increases the tendency
of the blood to clot in arteries.
5) Reduction in Alcohol intake : - Ethanol ( ethyl alcohol) in small amounts
10 - 20 ml maximum per day) may not be harmful.
6) Regular exercise keeps healthy : - Regular , rhythmic physical activities
in the form of brisk walking, or slow jogging, performed daily , will reduce
High blood pressure by dilating blood vessels and loss of salt and water
from the body through perspiration. But if the BP is very high in the
beginning, the exercises are deffered till BP is brought under control
and doctor should be consulted before starting exercises.
7) Meditation and Yoga : - In patients with High blood pressure some
chemical substances in the body produced in excess causing High
blood pressure. Their production will be reduced by meditation, thus
lowering the BP.
Writer................ Dr. A. Jayarajan MD.
Summary by .... R.Krishnakumar.
1) Weight reduction :- " Excess weight at any age is associated with
more hypertension, apart fom the risk of coronary heart disease".
a) Obesity may also be associated with diabetes.
b) There is an association between diabetes and high blood pressure.
c) Calorie restriction results in a fall in high blood pressure.
d) Whether it is diet restriction plus modified fasting, it should work
without endangering the health of the person.
e) The weight reduction must be slow and steady.
f) In medical term over weight is called obesity.
g) Over weight or obesity occurs in people where food intake
exceeds the energy requirements of the body for physical
activity and growth. As a result, there is accumulation of fat
which is stored in a dispose tissue (fat cells). This storage
may be localised in certain parts of the body.
h) It is proved that harmones from pituitary, thyroid and adernal
glands along with insulin and sex harmones have an important
role in regulating the fat metabolism.
i) In the adults, an increase in body weight may reflect an increase
in fat in a dispose tissue, an accumulation of fluid or both.
j) Weight gain excess of 1kg per day almost invariably implies
excess fluid retentation
k) Caution:- Every one should appreciate that any programme
which results in weight loss more than 0.3 kg per day undoubtedly
represents large amounts fluid loss rather than fat.
The weight reduction must be slow and steady.
A person is considered over weight if he exceeds the upper range of
ideal weight for his body frame. He is considered as obese if his weight
exceeds by 9 to 10 kgs his ideal weight.
m) Caution : - Obesity (Over weight) is the commonest predisposing cause
for the following problems
1) Diabetes Mellitus ( Excessive blood sugar )
2) Hypercholesterolaemia ( High blood cholesterol ).
3) Hypertension ( High blood pressure )
4 ) Ischaemic heart disease ( heart attacks ).
5) Osteoarthritis of weight bearing joints ( Hips, knees and ankles ).
6) Lumbar and Cervical Spondylosis.
7) Varicose veins ( Dilated, tortuous veins in legs).
8) Hernias, particularly incisional hernia, after operations.
9) Galler blader stones.
Diet and exercises are the only methods to attain ideal weight.
2) Avoid Rich food : - Chocolates, softies, ice creams, oily spice foods,
tinned & stored foods( animal fat foods).
Take more fibre and less saturated fat : - Increase in use of unsaturated
fats ( sun flower oil, corn oil) can induce lower blood pressures. Take
high - fibre foods like vegetables, fruits, bran, cereals etc.
3) Restriction of salt (sodium) intake to 1g per day. Avoid permanently
mangoe pickles and other pickles.
4) Stop Smoking permanently : - smoking immediately accelerates heart
rate and shoots up blood pressure which imposes extra burden on the
heart. Heavy smoking The Nicotin in tobacco increases the tendency
of the blood to clot in arteries.
5) Reduction in Alcohol intake : - Ethanol ( ethyl alcohol) in small amounts
10 - 20 ml maximum per day) may not be harmful.
6) Regular exercise keeps healthy : - Regular , rhythmic physical activities
in the form of brisk walking, or slow jogging, performed daily , will reduce
High blood pressure by dilating blood vessels and loss of salt and water
from the body through perspiration. But if the BP is very high in the
beginning, the exercises are deffered till BP is brought under control
and doctor should be consulted before starting exercises.
7) Meditation and Yoga : - In patients with High blood pressure some
chemical substances in the body produced in excess causing High
blood pressure. Their production will be reduced by meditation, thus
lowering the BP.
Writer................ Dr. A. Jayarajan MD.
Summary by .... R.Krishnakumar.
Over Weight Children Prone to Diabetes
OVER WEIGHT CHILDREN PRONE TO DIABETES
Childhood obesity is seen in 40% of children according
to several surveys.
Obesity leads to type - 2 diabetes, hypertension and
dyslipidemia ( excess of fat in blood ). Once those
complications develop they become permanent.They lead
to major health problems and needs continous care.
Medication becomes continous and life long.
childhood obesity is precipiating type - 2 diabetes
in the teenage group.
All of us are born with an average birth weight of
2.5kg to 3kg.
we increase in height as we grow and reach a standard
weight when we become adults, unless we fall into the
trap of obesity.
We double our birth weight at three months( that is we
reach 5kg - 6kg).We double the weight at one year(10-12kg).
The next doubling is when we are five years old ( 20-24kg).
The next doubling is at 15 years of age (40 - 50 kg).
After that there is a slow increase depending on the height
we reach.
We stabilise our weight between 60kgs and 80kg depending
on our height.
If we do not take care, we put on weight easily and this
leads to serious permanent health problem early in life.
It is very easy to put on weight but very difficult to
lose it. so it is wise not to put on weight.
Childhood obesity is seen in 40% of children according
to several surveys.
Obesity leads to type - 2 diabetes, hypertension and
dyslipidemia ( excess of fat in blood ). Once those
complications develop they become permanent.They lead
to major health problems and needs continous care.
Medication becomes continous and life long.
childhood obesity is precipiating type - 2 diabetes
in the teenage group.
All of us are born with an average birth weight of
2.5kg to 3kg.
we increase in height as we grow and reach a standard
weight when we become adults, unless we fall into the
trap of obesity.
We double our birth weight at three months( that is we
reach 5kg - 6kg).We double the weight at one year(10-12kg).
The next doubling is when we are five years old ( 20-24kg).
The next doubling is at 15 years of age (40 - 50 kg).
After that there is a slow increase depending on the height
we reach.
We stabilise our weight between 60kgs and 80kg depending
on our height.
If we do not take care, we put on weight easily and this
leads to serious permanent health problem early in life.
It is very easy to put on weight but very difficult to
lose it. so it is wise not to put on weight.
Fruits and Broccoli Fight Type 2 Diabetes
Fruits and broccoli could help
fight Type 2 diabetes
CONTRARY TO the belief that fruits
will enhance blood sugar levels and
aggravate problems associated with
diabetes, a team of scientists from
united kingdom has found that greater
intake of fruits and vegetables will
fact decrease the risk of Type 2
diabetes.
The UK research study showed that
higher plasma vitamin C level, and,
to a lesser extent, fruit vegetable
intake, were associated with a
decreased risk of Type 2 diabetes
that commonly affect adults.
Type 2 diabetes need not take insulin
injections as against those suffering
from Type 1 or insulin dependent
diabetes. More than 20,000 men and
women were studied as part of the
research. Since fruits and vegetables
are the main sources of vitamin C,
the study suggests that eating even
a small quantity of fruits and
vegetables may be beneficial and that
the protection against diabetes
increases progressively with the
quantity of fruit and vegetables
consumed.The Georgia university
researchers of USA tested extracts
24 common herbs and spices and found
that many contained high levels of
inflammation - inhibiting antioxidant
compounds known as polyphenols.Some
of thecommon herbs and spices may help
block the inflammation believed to
drive diabetes and other chronic
diseases.Broccoli contains a chemical
called sulforaphane which works wonders
with the circulatory system.
fight Type 2 diabetes
CONTRARY TO the belief that fruits
will enhance blood sugar levels and
aggravate problems associated with
diabetes, a team of scientists from
united kingdom has found that greater
intake of fruits and vegetables will
fact decrease the risk of Type 2
diabetes.
The UK research study showed that
higher plasma vitamin C level, and,
to a lesser extent, fruit vegetable
intake, were associated with a
decreased risk of Type 2 diabetes
that commonly affect adults.
Type 2 diabetes need not take insulin
injections as against those suffering
from Type 1 or insulin dependent
diabetes. More than 20,000 men and
women were studied as part of the
research. Since fruits and vegetables
are the main sources of vitamin C,
the study suggests that eating even
a small quantity of fruits and
vegetables may be beneficial and that
the protection against diabetes
increases progressively with the
quantity of fruit and vegetables
consumed.The Georgia university
researchers of USA tested extracts
24 common herbs and spices and found
that many contained high levels of
inflammation - inhibiting antioxidant
compounds known as polyphenols.Some
of thecommon herbs and spices may help
block the inflammation believed to
drive diabetes and other chronic
diseases.Broccoli contains a chemical
called sulforaphane which works wonders
with the circulatory system.
Fruits Can Make You Obese
FRUITS CAN MAKE YOU OBESE
A study has shown that fructose the
natural sugar found in fresh fruits
is also a cause for obesity.
Many fruits are very high in sugar
content and snacking on them all day
can lead to obesity eventually.
Especially in the abdominal area,
resulting in a pot belly.
FRUIT SUGAR TABLE
HIGH SUGAR LOW SUGAR
Apples, Berries
Cherries, Watermelon
Grapes, Melons
Mangoes, Tomatoes
Pears, Apricots
Pineapple, Grapefruit
Pomegranates, Guava
Bananas, Limes
Figs, Oranges
Prunes, Papayas
Dried Fruits Peaches
Fruits like apples,pears, oranges,
and others are not flattening but
heaps of natural sugar content,
which like all things - is good in
small amounts. The problem arises
if you eat 20 pieces of fruit.
The recommended serving is 1 -3
pieces per day. Other items to be
slowed down on are juices and jams
which are also high in fructose
content. According to Dr Dhiraj
palena, general physician and
nutrition consultant. " Fruit
juices contain as much, if not
more, carbohydrates and energy
than sweetened cold drinks.
It is when one adds table sugar
to fruits in salads or juices
that increases the level of sugar
in the dish, causing flattening
problems.Eating the skin of the
fruit which has important nutrients
can help negate sugar content.
Fructose(fruit sugar) is less harmful
than sucrose(table sugar).Fruit sugar
is better than table sugar. By eating
sucrose our bodies go out of sync with
the sugar processed in the body
extremely fast. Fructose is broken
down more slowly which allows the
body more time to react.
A study has shown that fructose the
natural sugar found in fresh fruits
is also a cause for obesity.
Many fruits are very high in sugar
content and snacking on them all day
can lead to obesity eventually.
Especially in the abdominal area,
resulting in a pot belly.
FRUIT SUGAR TABLE
HIGH SUGAR LOW SUGAR
Apples, Berries
Cherries, Watermelon
Grapes, Melons
Mangoes, Tomatoes
Pears, Apricots
Pineapple, Grapefruit
Pomegranates, Guava
Bananas, Limes
Figs, Oranges
Prunes, Papayas
Dried Fruits Peaches
Fruits like apples,pears, oranges,
and others are not flattening but
heaps of natural sugar content,
which like all things - is good in
small amounts. The problem arises
if you eat 20 pieces of fruit.
The recommended serving is 1 -3
pieces per day. Other items to be
slowed down on are juices and jams
which are also high in fructose
content. According to Dr Dhiraj
palena, general physician and
nutrition consultant. " Fruit
juices contain as much, if not
more, carbohydrates and energy
than sweetened cold drinks.
It is when one adds table sugar
to fruits in salads or juices
that increases the level of sugar
in the dish, causing flattening
problems.Eating the skin of the
fruit which has important nutrients
can help negate sugar content.
Fructose(fruit sugar) is less harmful
than sucrose(table sugar).Fruit sugar
is better than table sugar. By eating
sucrose our bodies go out of sync with
the sugar processed in the body
extremely fast. Fructose is broken
down more slowly which allows the
body more time to react.
Snoring and Sleep Apnoea
Snoring and sleep apnoea
Sleep apnoea is a sleeping disorder
that stops a person's breathing upto
hundreds of times each night.It occurs
when the airway collapses and air flow
to the lungs is blocked.Breathing pauses
can last from a few seconds to minutes,
depriving various organs like the brain
and heart of oxygen supply during sleep.
SYMPTOMS : - Though snoring is a primary
symptom of sleep apnoea,not all snorers
suffer from the disorder.
Snoring is the noise caused by air
passing through a partially obstructed
upper air way tract.
The common causes are deviated nasal
septum,growths in the nose,adenoids and
large tonsils,large soft palate and
elongated uvula, large tongue, tumours
and developmental abnormalities of the
lower jaw.
Snoring is three times more common in
obese people.
SNORING HARMFUL ? -> Severe snoring
will be a bigger problem- sleep opnoea.
Left untreated,it can destroy life.
ENT examination is carried.
The patient may have to undergo a PSG
(Polysomnography) test where various
parameters are checked while the patient
is asleep.
TREATMENT OPTIONS : - There are several
self-help methods like weight reduction,
regular exercise, and sleeping on your
side instead of your back.
Sleep apnoea is a sleeping disorder
that stops a person's breathing upto
hundreds of times each night.It occurs
when the airway collapses and air flow
to the lungs is blocked.Breathing pauses
can last from a few seconds to minutes,
depriving various organs like the brain
and heart of oxygen supply during sleep.
SYMPTOMS : - Though snoring is a primary
symptom of sleep apnoea,not all snorers
suffer from the disorder.
Snoring is the noise caused by air
passing through a partially obstructed
upper air way tract.
The common causes are deviated nasal
septum,growths in the nose,adenoids and
large tonsils,large soft palate and
elongated uvula, large tongue, tumours
and developmental abnormalities of the
lower jaw.
Snoring is three times more common in
obese people.
SNORING HARMFUL ? -> Severe snoring
will be a bigger problem- sleep opnoea.
Left untreated,it can destroy life.
ENT examination is carried.
The patient may have to undergo a PSG
(Polysomnography) test where various
parameters are checked while the patient
is asleep.
TREATMENT OPTIONS : - There are several
self-help methods like weight reduction,
regular exercise, and sleeping on your
side instead of your back.
HARMONIC FILTERATION
HARMONIC FILTERATION The increasing developments need increasing use of electricity While meeting this power demand, there causes a pollution in electrical system called Harmonics. Harmonic Analysis:- process of determining the magnitude, order and phase of the several harmonics present in a complex periodic wave. What Hazards created by Harmonics:- ----------------------------------- 1) Amplification of harmonic levels resulting from series and parallel resonance, reduction of efficiency of power generation, transmission and utilization. 2) Plant Mal-functioning. 3) Malfunctioning & Amp; failure of electronic equipments. 4) Over heating & failure of electrical motors. 5) Overloading,Overheating & failure of P.f correction capacitors. Resonance due to interaction of capacitor with harmonics. 6) Overloading & Overheating of distribution Transformers and neutral conductors. 7) Excessive measurement errors. 8) Spurious operation of Fuses, circuit Breakers & other protective Equipments. 9) Voltage glitches in computer systems resulting in losting data. Excessive flickers on VDU''''S. 10) Electromagnetic interface with TV,radio, communication & Telephone systems. 11) Damage & disruption to stand by generators & associated AVR control Equipment. 12) Interface with ripple control systems. For carrying out this analysis, the following methods are available which are all based on Fourier theorem:- 1) Analytical method - standard Fourier Analysis. 2) Graphical method - a) superposition method b) Twenty four ordinate method. To eliminate Harmonics the AIM EUROPE FILTER incorporates all of the following:- 1) Harmonic Mitigation 2) Reactive current control 3) load side transient suppression 4) Load side surge suppression. 5) Reduces the effect of supply sags & surges (flickers). How the AIM filter works:- ------------------------- 1) The AIM filter continously monitors the harmonic currents demanded by the load and generates an adaptive wave form which matches exactly the shape of the non linear portion of the load current. 2) AIM injects this adaptive current into the load point of connection only fundamental current is drawn from the source of the load. 3) Compensates from the 2nd to the 51st harmonic in a response t
OCEAN THERMAL ENERGY CONVERSION TECHNOLOGY
OCEAN THERMAL ENERGY CONVERSION TECHNOLOGYPresent a source of energy which is the son of the sun and ocean.
OTEC is an energy that converts solar radiation into usable energy.
Ocean thermal energy conversion or OTEC can produce a significant
amount of power because of the difference between the warm surface
of sea water and the deep cold ocean water.
The oceans cover a little more than 70 percent of earths surface.
This makes it the world''s largest solar energy collector and energy
storage sytem.
On an average day,60 million square kilometers of tropical seas absorb
an amount of solar radiational equal in heat content to about 250 billion
barrels of oil.
OTEC, Ocean Thermal Energy conversion is an energy technology that converts
solar radiation to electric power.
The oceans are thus a vast renewable resource, with potential to help us
produce billions of watts of electric power.
The cold seawater used in the OTEC process is also rich in nutrients and it
can be used to culture both marine organisms and plant life near the shore
or on land.
The idea behind OTEC is the use of all natural collectors,thesea,instead of
artificial collector.
Warm water is collected on the surface of the tropical ocean and pumped by
a warm water pump. The water is pumped through boiler, where some of the
water is used to heat the working fluid, usually propane or some similar
material.If it is cooler you can use a material with a lower boiling point
like ammonia.
The propane vapour expands through a turbine which is coupled to a generator
that generating electric power.
Cold water from the bottom is pumped through condensers,where the vapour
returns to the liquid state. The fluid is pumped back into the boiler.
There are two different kinds of OTEC power plants, the Land based and the
floating plant.
Land - based power plant : The land based pilot plant will consist of
a building. This building will contain the heat exchangers,turbines,
generators and controls.
It will connected to the ocean via several pipes, and an enormous fish
farm (100 football arenas) by other pipes.
Warm water is collected through a screened enclosure close to the shore.
A long pipe laid on the slope collects cold water. Power and fresh water
are generated in the building by the equipment.
Used water is first circulated into the marine culture pond (fish farm)
and then discharges by the third pipe into the ocean, downstream from the
warm inlet.
This is done so that the outflow does not reenter the plant, since re-use
of warm water would lower the available temperature difference.
Floating power plant : works in the same way as the land based the apparent
difference is that the floating plant is floating.
Closed - cycle, open -cycle and hybrid - cycle : - There are three types of
OTEC designs: open cycle,closed cycle, and hybrid cycle.
In an open cycle, seawater is the working fluid. Warm seawater is pumped into
flash evaporator where pressure as low as 0.03 bar cause the water to boil
at temperatures of 22 centigrades. This steam expands through a low pressure
turbine connected to a generator to create power.The steam then passes
through a condenser using cold seawater from the depths of the ocean to
condense the steam into desalinised water.
In a closed cycle, a low boiling point liquid such as ammonia or another
type of refrigerant is used as the working fluid in a Rankine cycle
(common steam cycle).
The heat from warm seawater flowing through an evaporator vaporises the
working fluid.
The vapour expands through a turbine, and then flows into a condenser
where cold seawater condenses it into a liquid.
OTEC is an energy that converts solar radiation into usable energy.
Ocean thermal energy conversion or OTEC can produce a significant
amount of power because of the difference between the warm surface
of sea water and the deep cold ocean water.
The oceans cover a little more than 70 percent of earths surface.
This makes it the world''s largest solar energy collector and energy
storage sytem.
On an average day,60 million square kilometers of tropical seas absorb
an amount of solar radiational equal in heat content to about 250 billion
barrels of oil.
OTEC, Ocean Thermal Energy conversion is an energy technology that converts
solar radiation to electric power.
The oceans are thus a vast renewable resource, with potential to help us
produce billions of watts of electric power.
The cold seawater used in the OTEC process is also rich in nutrients and it
can be used to culture both marine organisms and plant life near the shore
or on land.
The idea behind OTEC is the use of all natural collectors,thesea,instead of
artificial collector.
Warm water is collected on the surface of the tropical ocean and pumped by
a warm water pump. The water is pumped through boiler, where some of the
water is used to heat the working fluid, usually propane or some similar
material.If it is cooler you can use a material with a lower boiling point
like ammonia.
The propane vapour expands through a turbine which is coupled to a generator
that generating electric power.
Cold water from the bottom is pumped through condensers,where the vapour
returns to the liquid state. The fluid is pumped back into the boiler.
There are two different kinds of OTEC power plants, the Land based and the
floating plant.
Land - based power plant : The land based pilot plant will consist of
a building. This building will contain the heat exchangers,turbines,
generators and controls.
It will connected to the ocean via several pipes, and an enormous fish
farm (100 football arenas) by other pipes.
Warm water is collected through a screened enclosure close to the shore.
A long pipe laid on the slope collects cold water. Power and fresh water
are generated in the building by the equipment.
Used water is first circulated into the marine culture pond (fish farm)
and then discharges by the third pipe into the ocean, downstream from the
warm inlet.
This is done so that the outflow does not reenter the plant, since re-use
of warm water would lower the available temperature difference.
Floating power plant : works in the same way as the land based the apparent
difference is that the floating plant is floating.
Closed - cycle, open -cycle and hybrid - cycle : - There are three types of
OTEC designs: open cycle,closed cycle, and hybrid cycle.
In an open cycle, seawater is the working fluid. Warm seawater is pumped into
flash evaporator where pressure as low as 0.03 bar cause the water to boil
at temperatures of 22 centigrades. This steam expands through a low pressure
turbine connected to a generator to create power.The steam then passes
through a condenser using cold seawater from the depths of the ocean to
condense the steam into desalinised water.
In a closed cycle, a low boiling point liquid such as ammonia or another
type of refrigerant is used as the working fluid in a Rankine cycle
(common steam cycle).
The heat from warm seawater flowing through an evaporator vaporises the
working fluid.
The vapour expands through a turbine, and then flows into a condenser
where cold seawater condenses it into a liquid.
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