What we know as satellite tv actually had its origins in the space race which began with the launching of the satellite Sputnik by the Russians in 1957. The first communication satellite was developed and launched by a consortium of business and government entities in 1963. It was known as Syncom II and achieved an orbit at 22,300 miles over the Atlantic. The first satellite communication was between a U.S. Navy ship in the harbor of Lagos, Nigeria and the U.S. Army located at the naval station at Lakehurst, New Jersey on July 26, 1963.
Telephone companies began using satellite communication for communicating as land based distribution methods became overloaded. Television began using satellites on March 1, 1978 when the Public Broadcasting Service (PBS) introduced Public Television Satellite Service. Broadcast networks adopted satellite communication as a distribution method from 1978 through 1984. As the use of satellites for communication and broadcast purposes increased, it became evident that everyone had the potential to receive satellite signals for free.
Direct to Home (DTH) satellite receivers were developed in the early 1980's. Rural areas thus gained the capacity to receive television programming that was not capable of being received by standard methods. With the development of television receive only (TVRO), broadcasters began to complain that reception of their signals were being either received illegally or pirated. The position of the Federal Communications Commission (FCC) was governed by its "open skies' policy. It was the FCC's position that users had as much right to receive satellite signals as broadcasters had the right to transmit them.
The broadcasters, in response to this government policy, began to use developed technologies which allowed them to scramble the signals they were broadcasting. Users, in turn, had to buy a decoder from a satellite program provider that packaged programs similar to the packages provided by cable systems. Ideas began to abound about the potential market for satellite television. The FCC, following the World Administrative Radio Conference of 1979, in 1980 established the plans and policy for a new service, direct broadcast satellite or DBS. This new service was to consist of a broadcast satellite in geostationary orbit, facilities for transmitting signals to the satellite and equipment needed by individuals to access the signals.
Early successful attempts to launch satellites for the mass consumer market were led by Japan and Hong Kong in 1986 and 1990, respectively. The first successful attempt by the United States was made by a group of major cable companies and was named Primestar. Next came Direct TV. Echostar Dish Network entered the market in the Spring of 1996 offering cheaper prices and forcing all of its competitors to do likewise.
See Also
Telephone companies began using satellite communication for communicating as land based distribution methods became overloaded. Television began using satellites on March 1, 1978 when the Public Broadcasting Service (PBS) introduced Public Television Satellite Service. Broadcast networks adopted satellite communication as a distribution method from 1978 through 1984. As the use of satellites for communication and broadcast purposes increased, it became evident that everyone had the potential to receive satellite signals for free.
Direct to Home (DTH) satellite receivers were developed in the early 1980's. Rural areas thus gained the capacity to receive television programming that was not capable of being received by standard methods. With the development of television receive only (TVRO), broadcasters began to complain that reception of their signals were being either received illegally or pirated. The position of the Federal Communications Commission (FCC) was governed by its "open skies' policy. It was the FCC's position that users had as much right to receive satellite signals as broadcasters had the right to transmit them.
The broadcasters, in response to this government policy, began to use developed technologies which allowed them to scramble the signals they were broadcasting. Users, in turn, had to buy a decoder from a satellite program provider that packaged programs similar to the packages provided by cable systems. Ideas began to abound about the potential market for satellite television. The FCC, following the World Administrative Radio Conference of 1979, in 1980 established the plans and policy for a new service, direct broadcast satellite or DBS. This new service was to consist of a broadcast satellite in geostationary orbit, facilities for transmitting signals to the satellite and equipment needed by individuals to access the signals.
Early successful attempts to launch satellites for the mass consumer market were led by Japan and Hong Kong in 1986 and 1990, respectively. The first successful attempt by the United States was made by a group of major cable companies and was named Primestar. Next came Direct TV. Echostar Dish Network entered the market in the Spring of 1996 offering cheaper prices and forcing all of its competitors to do likewise.
See Also
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Science
| Sunday, August 29, 2010
During the speach, Dr. Reg McDaniel talked about first seeing new stem cells in the peripheral blood of clients using glyconutrients many years ago and not recognizing these cells as stem cells. They were 10 times the size of white blood cells and they were given the name "Gee" cells for some time as that's what Dr. Reg said when he observed these new cells that no one could identify! Now we have the tools to identify these cells appropriately as stem cells which can be used as "master keys" to move to places in the body as the body calls for. About a year ago there was an article in JAMA regarding the stem cells implants of male cells into female bodies of women with leukemia who had received a stem cell transplant. When these women died, male marked cells were found as neurons in the brain.
Dr. Reg realized that this might offer an explanation in the many children with fetal alcohol syndrome that were doing so well with the glyconutrients and others who had advanced so far beyond their perceived genetic limitations. He told the story of several adopted aboriginal children in Canada who had fetal alcohol syndrome who have done remarkably well, improving from IQ's estimated to be around 50 to levels around 100. One girl who had difficulties with reading and numbers and was in remedial classes after 3 years with glyconutrients was able to read a Harry Potter book in a week and discuss what she had read.
When they measure the before and after stem cell counts in the blood, virtually none are detectable prior to glyconutrieints. Within a week of giving glyconutrients, there are 200-400 stem cells seen in a microliter of blood with about 5-10 thousand white blood cells. If one extrapolates to the whole body, it is possible that there are 1.7-3 trillion new stem cells throughout our body as we add in glyconutrients. We're at the beginning of understanding all of what is possible with stem cells. There is an article in the June Scientific American if you want to read more about stem cells.
A New STEM CELL SURVEY CD for the Health Care Professional will be available next week that contains evidence that glyconutrients increase Stem Cell activity in the human body (This is a presentation CD not an audio CD). This NEW Stem Cell CD by H. Reg McDaniel, M.D. documents how glyconutrients integrated into traditional therapy may benefit every disease that Stem Cells benefit and THAT IS EVERY DISEASE.
Note: Glyconutrients are not intended to heal, treat, or cure any disease
See Also
Dr. Reg realized that this might offer an explanation in the many children with fetal alcohol syndrome that were doing so well with the glyconutrients and others who had advanced so far beyond their perceived genetic limitations. He told the story of several adopted aboriginal children in Canada who had fetal alcohol syndrome who have done remarkably well, improving from IQ's estimated to be around 50 to levels around 100. One girl who had difficulties with reading and numbers and was in remedial classes after 3 years with glyconutrients was able to read a Harry Potter book in a week and discuss what she had read.
When they measure the before and after stem cell counts in the blood, virtually none are detectable prior to glyconutrieints. Within a week of giving glyconutrients, there are 200-400 stem cells seen in a microliter of blood with about 5-10 thousand white blood cells. If one extrapolates to the whole body, it is possible that there are 1.7-3 trillion new stem cells throughout our body as we add in glyconutrients. We're at the beginning of understanding all of what is possible with stem cells. There is an article in the June Scientific American if you want to read more about stem cells.
A New STEM CELL SURVEY CD for the Health Care Professional will be available next week that contains evidence that glyconutrients increase Stem Cell activity in the human body (This is a presentation CD not an audio CD). This NEW Stem Cell CD by H. Reg McDaniel, M.D. documents how glyconutrients integrated into traditional therapy may benefit every disease that Stem Cells benefit and THAT IS EVERY DISEASE.
Note: Glyconutrients are not intended to heal, treat, or cure any disease
See Also
Posted in:
Science
|
Telescopes are devices that are used to view the distant objects. They find its use in astronomy and physics. It enables you to view the distant objects by magnifying them. There are many types of telescopes and their prices vary according to the specifications. Many accessories are also available that can be used in conjunction with the telescopes. Small telescopes that are used as toys are also capable of viewing some objects around 50 meters away.
Some of the world's largest optical telescopes in operation
We say a telescope to be larger based on the aperture size. Based on this we can say that Keck and Keck II are the largest telescopes in operation with an aperture of 10 meters diameter. The Keck telescope is composed of 36 mirror segments. This is located at Mauna Kea, Hawaii. The next largest is Hobby-Eberly located at Mt. Fowlkes, Texas which has an aperture of 9.2 meters. You can get a list of the largest optical telescopes at http://astro.nineplanets.org/bigeyes.html.
Principle in which the telescope works
The principle in which the telescope works is very simple. There are two lenses that make up the task of viewing the objects that are at a distance. One of the lenses picks up the light from the object viewed and makes it available at a focus point. Another lens picks up the bright light from the focus point and spreads it out to your retina so that you can view. The lens that picks up the light from the object is called the objective lens or primary mirror. The lens that picks up the light from the focal point is called the eyepiece lens.Factors that affect the viewing of the object
The capability of the telescope to collect the light from the object that is viewed and the capability to enlarge the image are the factors that affect the efficiency of the telescope. The capability to collect light from the object depends on the diameter of the lens or mirror, which is otherwise called the aperture. The larger the aperture the more the light it can collect. Enlarging of an image depends on the combination of the lenses that are used. The eyepiece in the telescope performs the magnification.Some of the world's largest optical telescopes in operation
We say a telescope to be larger based on the aperture size. Based on this we can say that Keck and Keck II are the largest telescopes in operation with an aperture of 10 meters diameter. The Keck telescope is composed of 36 mirror segments. This is located at Mauna Kea, Hawaii. The next largest is Hobby-Eberly located at Mt. Fowlkes, Texas which has an aperture of 9.2 meters. You can get a list of the largest optical telescopes at http://astro.nineplanets.org/bigeyes.html.
Choosing your telescope
The choice of the telescope largely depends on what you want to observe. You can choose compound telescopes and refractor type of telescope for viewing through the urban skies. For the rural skies, you can use compound telescopes and reflectors. They are better than the refractors type of telescopes. Each type has its own advantages and disadvantages. Hence, many people have different telescope for different purposes.Posted in:
Science
| Saturday, August 28, 2010
Students often ask; "What exactly is science?" Professors explain by discussing theories, proofs, laws of physics, observations, duplication of results, etc.. Professors often pull rank on students when they argue a point with the professor on extending the professors definition of science. When this occurs the professor indicates to the student; "You obviously do not know what science is" they quickly tell the student.
Having had this scenario play over and over again, it would appear that those professors want to keep science for themselves. If they cannot answer a question or do not know the answer they will simply say; "that is not science" or "that is pseudo science" thus alleviating them the responsibility of answering the question. This is interesting indeed.
I have often thought; "science does not know what science is!" Science is not condemning another who caries a different perspective, science is not character assonating another in a primate political way to put forth their ideas or concepts over another. Since is not attacking someone's concept because it does not match with what another was taught, science is not publish or perish over real breakthroughs. Science is not who publishes first or whose name is attached. Science is not engineering. Science is not denying a theory until you can prove it is not possible. Science is not rhetoric, that is politics.
Although in observing all the above discussion about what science is not and it appears that in the "real" world of science one observing these behaviors might perceive it to be just that. But such social interaction which actually occurs in science is not science at all, unless you call it "social science" but most scientists claim that is not a real science and if so why don't they practice what they preach and dump the rhetoric? What all these scientists and professor's are doing is not science, it is disgusting.
I think I enjoy the comments on this subject by Bill Bryson, Matt Ridley, Stephen Wolfram and recently Michael Crieghton in his book "Fear." In any case all you scientists out there need to dump the BS and get busy propelling the human race and forwarding the progression of the species, you are not fooling me and many are simply getting quite tired of games. Think on that why don't you?
Having had this scenario play over and over again, it would appear that those professors want to keep science for themselves. If they cannot answer a question or do not know the answer they will simply say; "that is not science" or "that is pseudo science" thus alleviating them the responsibility of answering the question. This is interesting indeed.
I have often thought; "science does not know what science is!" Science is not condemning another who caries a different perspective, science is not character assonating another in a primate political way to put forth their ideas or concepts over another. Since is not attacking someone's concept because it does not match with what another was taught, science is not publish or perish over real breakthroughs. Science is not who publishes first or whose name is attached. Science is not engineering. Science is not denying a theory until you can prove it is not possible. Science is not rhetoric, that is politics.
Although in observing all the above discussion about what science is not and it appears that in the "real" world of science one observing these behaviors might perceive it to be just that. But such social interaction which actually occurs in science is not science at all, unless you call it "social science" but most scientists claim that is not a real science and if so why don't they practice what they preach and dump the rhetoric? What all these scientists and professor's are doing is not science, it is disgusting.
I think I enjoy the comments on this subject by Bill Bryson, Matt Ridley, Stephen Wolfram and recently Michael Crieghton in his book "Fear." In any case all you scientists out there need to dump the BS and get busy propelling the human race and forwarding the progression of the species, you are not fooling me and many are simply getting quite tired of games. Think on that why don't you?
Posted in:
Science
|
The reason for the apparently absurd question in the title is the remarkable research conducted at the University of Sheffield by neurology professor the late Dr. John Lorber.
When Sheffield's campus doctor was treating one of the mathematics students for a minor ailment, he noticed that the student's head was a little larger than normal. The doctor referred the student to professor Lorber for further examination.
The student in question was academically bright, had a reported IQ of 126 and was expected to graduate. When he was examined by CAT-scan, however, Lorber discovered that he had virtually no brain at all.
Instead of two hemispheres filling the cranial cavity, some 4.5 centimetres deep, the student had less than 1 millimetre of cerebral tissue covering the top of his spinal column. The student was suffering from hydrocephalus, the condition in which the cerebrospinal fluid, instead of circulating around the brain and entering the bloodstream, becomes dammed up inside.
Normally, the condition is fatal in the first months of childhood. Even where an individual survives he or she is usually seriously handicapped. Somehow, though, the Sheffield student had lived a perfectly normal life and went on to gain an honours degree in mathematics.
Professor Lorber (who was a member of the committee sitting to decide who should be awarded the Nobel Prize) identified several hundred people who have very small cerebral hemispheres but who appear to be normal intelligent individuals. Some of them he describes as having 'no detectable brain', yet they have scored up to 120 on IQ tests.
No-one knows how people with 'no detectable brain' are able to function at all, let alone to graduate in mathematics, but there are a couple theories. One idea is that there is such a high level of redundancy of function in the normal brain that what little remains is able to learn to deputise for the missing hemispheres.
Another, similar, suggestion is the old idea that we only use a small percentage of our brains anyway - perhaps as little as 10 per cent. The trouble with these ideas is that more recent research seems to contradict them. The functions of the brain have been mapped comprehensively and although there is some redundancy there is also a high degree of specialisation - the motor area and the visual cortex being highly specific for instance. Similarly, the idea that we 'only use 10 per cent of our brain' is a misunderstanding dating from research in the 1930s in which the functions of large areas of the cortex could not be determined and were dubbed 'silent', when in fact they are linked with important functions like speech and abstract thinking.
The other interesting thing about Lorber's findings is that they remind us of the mystery of memory. At first it was thought that memory would have some physical substrate in the brain, like the memory chips in a PC. But extensive investigation of the brain has turned up the surprising fact that memory is not located in any one area or in a specific substrate. As one eminent neurologist put it, 'memory is everywhere in the brain and nowhere.' But if the brain is not a mechanism for classifying and storing experiences and analysing them to enable us to live our lives then what on earth is the brain for? And where is the seat of human intelligence? Where is the mind?
Lorber's discovery is far from isolated. In researching my book 'Alternative Science' I found literally scores of such cases of scientific discoveries that are well-attested with strong direct laboratory evidence, and yet are ignored by conventional science. Many more such examples are also given on the Alternative Science Website.
When Sheffield's campus doctor was treating one of the mathematics students for a minor ailment, he noticed that the student's head was a little larger than normal. The doctor referred the student to professor Lorber for further examination.
The student in question was academically bright, had a reported IQ of 126 and was expected to graduate. When he was examined by CAT-scan, however, Lorber discovered that he had virtually no brain at all.
Instead of two hemispheres filling the cranial cavity, some 4.5 centimetres deep, the student had less than 1 millimetre of cerebral tissue covering the top of his spinal column. The student was suffering from hydrocephalus, the condition in which the cerebrospinal fluid, instead of circulating around the brain and entering the bloodstream, becomes dammed up inside.
Normally, the condition is fatal in the first months of childhood. Even where an individual survives he or she is usually seriously handicapped. Somehow, though, the Sheffield student had lived a perfectly normal life and went on to gain an honours degree in mathematics.
Professor Lorber (who was a member of the committee sitting to decide who should be awarded the Nobel Prize) identified several hundred people who have very small cerebral hemispheres but who appear to be normal intelligent individuals. Some of them he describes as having 'no detectable brain', yet they have scored up to 120 on IQ tests.
No-one knows how people with 'no detectable brain' are able to function at all, let alone to graduate in mathematics, but there are a couple theories. One idea is that there is such a high level of redundancy of function in the normal brain that what little remains is able to learn to deputise for the missing hemispheres.
Another, similar, suggestion is the old idea that we only use a small percentage of our brains anyway - perhaps as little as 10 per cent. The trouble with these ideas is that more recent research seems to contradict them. The functions of the brain have been mapped comprehensively and although there is some redundancy there is also a high degree of specialisation - the motor area and the visual cortex being highly specific for instance. Similarly, the idea that we 'only use 10 per cent of our brain' is a misunderstanding dating from research in the 1930s in which the functions of large areas of the cortex could not be determined and were dubbed 'silent', when in fact they are linked with important functions like speech and abstract thinking.
The other interesting thing about Lorber's findings is that they remind us of the mystery of memory. At first it was thought that memory would have some physical substrate in the brain, like the memory chips in a PC. But extensive investigation of the brain has turned up the surprising fact that memory is not located in any one area or in a specific substrate. As one eminent neurologist put it, 'memory is everywhere in the brain and nowhere.' But if the brain is not a mechanism for classifying and storing experiences and analysing them to enable us to live our lives then what on earth is the brain for? And where is the seat of human intelligence? Where is the mind?
Lorber's discovery is far from isolated. In researching my book 'Alternative Science' I found literally scores of such cases of scientific discoveries that are well-attested with strong direct laboratory evidence, and yet are ignored by conventional science. Many more such examples are also given on the Alternative Science Website.
Posted in:
Science
|
Tsunami is a Japanese term that describes a large seismically generated sea wave which is capable of considerable destruction in certain coastal areas, especially where underwater earthquakes occur.
In Japanese, "Tsunami" means "Harbor Wave" or "Wave In The Harbor" It is now internationally accepted as the term that defines a "Seismic Seawave."
In South America, the term "Maremoto" is frequently used to describe a Tsunami.
Tsunami is pronounced: (sue-NAM-ee)
Tsunami's have been incorrectly referred to as "tidal waves." A tidal wave is a non-technical term for a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth (high water is the crest of a tidal wave and low water is the trough).
Tsunami's are formed by a displacement of water. This can come from the slippage of the boundaries between two tectonic plates, volcanic eruption, under-water earthquake, or even landslides.
Out in the open ocean, Tsunami's might only be 1 meter in height, but as it reaches the shore in shallow water, it can rise to heights of 15-30 meters or more. Think about how a normal wave comes into a shore: the water moves away from the shore and then comes crashing back. This movement "heightens" the destruction power of a Tsunami.
Tsunami's can also reach speeds ranging from 400 to 500+ miles per hour? about the same speed as a jet airliner.
The enormous energy that a Tsunami can possess allows it to travel across entire oceans. They often proceed as an ordinary gravity wave? having a 15 to 60 minute intervals.
From a destruction perspective, Tsunami's have cost not hundreds of thousands, but millions of human lives over the recorded history of Earth.
Sources: U.S. Geological Survey & Pacific Tsunami Warning Center
In Japanese, "Tsunami" means "Harbor Wave" or "Wave In The Harbor" It is now internationally accepted as the term that defines a "Seismic Seawave."
In South America, the term "Maremoto" is frequently used to describe a Tsunami.
Tsunami is pronounced: (sue-NAM-ee)
Tsunami's have been incorrectly referred to as "tidal waves." A tidal wave is a non-technical term for a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth (high water is the crest of a tidal wave and low water is the trough).
Tsunami's are formed by a displacement of water. This can come from the slippage of the boundaries between two tectonic plates, volcanic eruption, under-water earthquake, or even landslides.
Out in the open ocean, Tsunami's might only be 1 meter in height, but as it reaches the shore in shallow water, it can rise to heights of 15-30 meters or more. Think about how a normal wave comes into a shore: the water moves away from the shore and then comes crashing back. This movement "heightens" the destruction power of a Tsunami.
Tsunami's can also reach speeds ranging from 400 to 500+ miles per hour? about the same speed as a jet airliner.
The enormous energy that a Tsunami can possess allows it to travel across entire oceans. They often proceed as an ordinary gravity wave? having a 15 to 60 minute intervals.
From a destruction perspective, Tsunami's have cost not hundreds of thousands, but millions of human lives over the recorded history of Earth.
Sources: U.S. Geological Survey & Pacific Tsunami Warning Center
Posted in:
Science
|
I have always been an advocate of recycling. Even though I am not always convinced of its financial viability, I am thoroughly convinced of its value as a means of increasing public awareness of the cost of our consumerism. In the 20+ years I have been in the organizing profession, I have never heard anyone complain that their problem in getting organized was that they didn't have enough "stuff."
It doesn't seem like getting rid of things should be such difficult issue, but in my own experience and in the lives of clients, it often is. I have spent countless hours listening to clients justify why they need to keep clothes they haven't worn in ten years, utensils they aren't sure how to use, appliances that need repair, artwork they don't even like -- and, of course, old magazines they're sure to read some day!
If you have enough room and if you're willing to pay the price in space and energy, it is possible to keep everything. But if you can't find what you need today because you're tripping over what you might need tomorrow, the price may be more than you should be willing to pay. Recycling is often a great solution.
It's amazing how many ways you can find to recycle the things you aren't using. Towels and bedding are desperately needed by homeless shelters. Pre-school programs can use calendars with pretty pictures. Local schools are often delighted to have used computer equipment. The Lions Club collects eyeglasses for people who cannot afford to purchase them. (How many pairs do you have in your dresser drawer?)
My mother had an enormous pile of overalls which my father no longer used, but she didn't know anyone who needed them. She just couldn't bring herself to toss them, so she put them in a box in the attic. One day she heard a woman on the radio say that she wanted to buy overalls because she used the bib tops to make jumpers which she sold to raise money for her favorite charity. She didn't even care if the overalls had holes in them, because she covered them up with decorations and trim. My mother was elated to find a home for the overalls -- and get a check for $10 besides! (One note of caution: Don't fall in a trap of looking for the perfect recipient -- organizations such as Goodwill Industries can use almost anything, and will give you a receipt for a tax deduction!)
It doesn't seem like getting rid of things should be such difficult issue, but in my own experience and in the lives of clients, it often is. I have spent countless hours listening to clients justify why they need to keep clothes they haven't worn in ten years, utensils they aren't sure how to use, appliances that need repair, artwork they don't even like -- and, of course, old magazines they're sure to read some day!
If you have enough room and if you're willing to pay the price in space and energy, it is possible to keep everything. But if you can't find what you need today because you're tripping over what you might need tomorrow, the price may be more than you should be willing to pay. Recycling is often a great solution.
It's amazing how many ways you can find to recycle the things you aren't using. Towels and bedding are desperately needed by homeless shelters. Pre-school programs can use calendars with pretty pictures. Local schools are often delighted to have used computer equipment. The Lions Club collects eyeglasses for people who cannot afford to purchase them. (How many pairs do you have in your dresser drawer?)
My mother had an enormous pile of overalls which my father no longer used, but she didn't know anyone who needed them. She just couldn't bring herself to toss them, so she put them in a box in the attic. One day she heard a woman on the radio say that she wanted to buy overalls because she used the bib tops to make jumpers which she sold to raise money for her favorite charity. She didn't even care if the overalls had holes in them, because she covered them up with decorations and trim. My mother was elated to find a home for the overalls -- and get a check for $10 besides! (One note of caution: Don't fall in a trap of looking for the perfect recipient -- organizations such as Goodwill Industries can use almost anything, and will give you a receipt for a tax deduction!)
Posted in:
Science
|
Many articles have been written about the negative effects of carbon dioxide. Sick Building Syndrome, loss of concentration due to high levels of carbon dioxide, asphyxiation in breweries or wine cellars, all these things spring to mind when we hear the magic phrase carbon dioxide. Yet, perhaps today when Venus passes across the face of the Sun, we should remember that our original atmosphere consisted of nitrogen and carbon dioxide. Free oxygen is something that is not really chemically possible. Yet we have it as a result of plant life busily photosynthesising and converting carbon dioxide into oxygen during daylight hours. This is the original use of solar energy!
Plants require carbon dioxide to grow and why not help them by increasing the level of carbon dioxide? Normally, this is something that is undesirable, since carbon dioxide is the original greenhouse gas, as our neighbouring planet Venus can testify. But in a controlled, genuine greenhouse environment, there is no real reason why the level of carbon dioxide should not be enhanced in some way.
Indeed, tests have shown that increasing the level of carbon dioxide in a greenhouse to 550 ppm will accelerate plant growth by 30 - 40 %. The natural level of carbon dioxide in the atmosphere is around 450 ppm, having increased from about 250 ppm in the last ice-age, so this slight increase may not appear significant at first sight. The point of the matter is that the level of carbon dioxide in the average greenhouse with the ventilation system closed will drop sharply due to uptake by the plants and will lie around 150 - 200 ppm if nothing is done about it. In summer the ventilation system will be open and the fresh air circulation will augment the level to a useful degree. But what about those long, cold, dark northern winters? Most commercial greenhouses will have lighting and heating systems to encourage plant growth, but you still cannot open the ventilation and allow the cold outside air into your heated greenhouse without losing all the early crops. The only real solution is to augment the natural level of carbon dioxide in some way. Where it is used, the general rule of thumb is to augment by about 1000 ppm when the sun is shining (or all the lights are on!) and keep the level around 400 ppm during times of darkness. This will require monitoring, since there are so many variable factors involved and a simple control unit using an infrared sensor will be able to keep the concentration of gas constant at all times.
Rate of consumption varies with crop, light intensity, temperature, stage of crop development and nutrient level. An average consumption level is estimated to be between 0.12 - 0.24 kg/hr/100 m2 of greenhouse floor area. The higher rate reflects the typical usage for sunny days and a fully-grown crop. This equates to roughly 150 litres of carbon dioxide per hour.
There are many processes that naturally and unavoidably produce carbon dioxide: Fermentation and combustion are two classic examples. In temperate zones it is necessary to heat a greenhouse (glasshouse is just another word for the same thing), and this heating will almost always involve the burning of fossil fuels, producing carbon dioxide. This leads to the natural urge to re-circulate the exhaust gas from the heating system into the greenhouse and so achieve a double advantage for the plants. This will require careful monitoring of the flue gas to ensure that there are at the most only traces of carbon monoxide being passed into the greenhouse. This is not only bad for the plants but also potentially lethal to the people working there! Such technology is available with gas monitors that will measure the carbon monoxide concentration continuously and have analogue outputs that can be used to regulate the burners or operate a trip to switch the unit off should problems occur. The combination of breweries with greenhouse systems is also serious business in some areas. Generally, these methods are to be approved and should really be worthy of government support. Not only are they producing crops, they are removing a pollutant that would otherwise be vented into the atmosphere.
Monitoring of the added carbon dioxide is essential, however, since high concnetrations of carbon dioxide can lead to dizziness or even unconciousness of the personnel. Some plants will require higher levels of nutrients to compensate for some of the changes that occur. Particularly tomatoes and violets are sensitive to increased levels of carbon dioxide, hence the need for constant monitoring of the ambient concentration.
Plants require carbon dioxide to grow and why not help them by increasing the level of carbon dioxide? Normally, this is something that is undesirable, since carbon dioxide is the original greenhouse gas, as our neighbouring planet Venus can testify. But in a controlled, genuine greenhouse environment, there is no real reason why the level of carbon dioxide should not be enhanced in some way.
Indeed, tests have shown that increasing the level of carbon dioxide in a greenhouse to 550 ppm will accelerate plant growth by 30 - 40 %. The natural level of carbon dioxide in the atmosphere is around 450 ppm, having increased from about 250 ppm in the last ice-age, so this slight increase may not appear significant at first sight. The point of the matter is that the level of carbon dioxide in the average greenhouse with the ventilation system closed will drop sharply due to uptake by the plants and will lie around 150 - 200 ppm if nothing is done about it. In summer the ventilation system will be open and the fresh air circulation will augment the level to a useful degree. But what about those long, cold, dark northern winters? Most commercial greenhouses will have lighting and heating systems to encourage plant growth, but you still cannot open the ventilation and allow the cold outside air into your heated greenhouse without losing all the early crops. The only real solution is to augment the natural level of carbon dioxide in some way. Where it is used, the general rule of thumb is to augment by about 1000 ppm when the sun is shining (or all the lights are on!) and keep the level around 400 ppm during times of darkness. This will require monitoring, since there are so many variable factors involved and a simple control unit using an infrared sensor will be able to keep the concentration of gas constant at all times.
Rate of consumption varies with crop, light intensity, temperature, stage of crop development and nutrient level. An average consumption level is estimated to be between 0.12 - 0.24 kg/hr/100 m2 of greenhouse floor area. The higher rate reflects the typical usage for sunny days and a fully-grown crop. This equates to roughly 150 litres of carbon dioxide per hour.
There are many processes that naturally and unavoidably produce carbon dioxide: Fermentation and combustion are two classic examples. In temperate zones it is necessary to heat a greenhouse (glasshouse is just another word for the same thing), and this heating will almost always involve the burning of fossil fuels, producing carbon dioxide. This leads to the natural urge to re-circulate the exhaust gas from the heating system into the greenhouse and so achieve a double advantage for the plants. This will require careful monitoring of the flue gas to ensure that there are at the most only traces of carbon monoxide being passed into the greenhouse. This is not only bad for the plants but also potentially lethal to the people working there! Such technology is available with gas monitors that will measure the carbon monoxide concentration continuously and have analogue outputs that can be used to regulate the burners or operate a trip to switch the unit off should problems occur. The combination of breweries with greenhouse systems is also serious business in some areas. Generally, these methods are to be approved and should really be worthy of government support. Not only are they producing crops, they are removing a pollutant that would otherwise be vented into the atmosphere.
Monitoring of the added carbon dioxide is essential, however, since high concnetrations of carbon dioxide can lead to dizziness or even unconciousness of the personnel. Some plants will require higher levels of nutrients to compensate for some of the changes that occur. Particularly tomatoes and violets are sensitive to increased levels of carbon dioxide, hence the need for constant monitoring of the ambient concentration.
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