Mar 17
As the temperature rises during the summer season, many households turn to more than just ice-cold drinks to keep them cool. Air conditioning was once regarded as a residential luxury, but has become something of a necessity throughout the United States. Not only will air conditioning cool a room to a bearable temperature during balmy, humid summer days, but also uses the same techniques as a refrigerator to provide ventilation and dehumidification for indoor air.
Brief Air Conditioning History
The concept of cooling spaces by using natural elements is one that can be traced to the times of ancient Egyptians, who circulated aqueduct water through the walls of various structures to produce a cooling effect. Even in those times, since water was scarce, wealthy residents were only able to enjoy this luxury. During hot weather, medieval Persians created wind towers to cool down buildings. It wasn’t until the early 1800s that a British scientist started to experiment with the compressing and liquefying of ammonia. He learned that liquefied ammonia could chill the air when it evaporated.
In 1842, an American doctor named John Gorrie created ice to cool the air of hospital patients and had dreams of using this technology to create a cooling machine for buildings. He tinkered with the plans of constructing an ice-making machine with the help of a financial backer. When his support was no longer available, he could no longer finance his experiments. When he passed away in 1855, the idea of air conditioning was also laid to rest for about 50 years.
After the attempts of Gorrie, industrial air conditioning was created in the early 1900s with the first modern electrical version of air conditioning. Throughout the years, a shift was seen in the use of air conditioning, as automobiles and households began to benefit from the invention. The Carrier Air Conditioning Company began to lead the way in bringing the concept to the public, and during the 1950s, it was a contagious residential dream.
The Pros and Cons
The benefit of enjoying a cooler atmosphere during heated weather is not the only advantage gained when turning on the air conditioner. A household, vehicle, and other building environment becomes cleaner and safer for breathing when air conditioning is able to prevent the growth and spread of harmful microorganisms. Individuals who suffer from allergies and asthma are especially thankful for the better atmosphere an air-conditioned room provides, as less dust and dander are present. In seriously hot weather, babies and the elderly also benefit from air conditioning as heat waves have been known to take the lives of those whose immune systems and health might not be the strongest.
One of the most controversial topics attached to the subject of air conditioning deals with some of the materials that are used to produce the cooling affect of these machines. Fluorocarbon refrigerants also contribute to global warming concerns, which serves as one of the main ways that air-conditioning impacts the state of the environmental world. Fluorocarbon refrigerants also add to the problems concerning ozone layer depletion.
While the temporary relief that air conditioning provides makes hot summer nights and heat waves a more bearable event, many question how much the world will pay in the long run after the environmental damage has settled. Today, scientists are working on making more environmental friendly products, but for now, individuals are reluctant to part with their instant cool during the thick of summer.
Derek Both
http://www.articlesbase.com/environment-articles/is-air-conditioning-doing-more-damage-than-good-108142.html
Feb 5
In order to stop night sweats naturally you should learn about the mechanics of sweating. There is no reason why you should suffer from night sweats ever again. Once you understand how sweating evolves, you will have the knowledge to make night sweats stop.
Your Body Uses The Following Methods To Keep Itself Cool:
* Radiation (radiant energy)
* Conduction (conductive heat transfer)
* Convection (conveyance of heat)
* Sweating (we are trying to avoid this)
Our body cools itself by four main methods. The first method is radiation. Radiation is like the heat that you feel while standing in front of an oven that is on.
The second method is conduction. Conduction is the heat that you feel if you touch the oven while it is on. The third method is called convection. Convection is heat that is picked-up by the air that passes by the oven while it is on.
Simply put, convection is heat that is conveyed to the air surrounding the hot object. The forth and final method of cooling is evaporation, better known as sweating.
Typically body cooling takes place in that very order. If the body will not cool itself via radiation, conduction, or convection, you will start to sweat.
The Temperature Pendulum
The objective here is to teach you how keep your body cool and keep from sweating at night. To fully understand how to manage night sweats you must understand each method of cooling your body in order to fully evaluate your options.
One thing you should make note of is that your body will normally maintain a relatively constant temperature throughout the night. The problem occurs when your body is not keeping a constant temperature during the day or night.
People that suffer from night sweats understand the concept of varying body temperature. Therefore you will look at the cooling cycle with that in mind.
A Balancing Act
The temperature balancing act starts when you get in bed at night. You feel the cool of the sheets and the comfort of the bed. This is a good example of conductive heat transfer. Whenever there is a difference in temperature between the object you are touching and your body, you will feel either a warming sensation or a cooling sensation.
Remember that heat travels from hot objects to cooler objects. So if you touch ice you feel cold because the heat is leaving your body and going into the ice.
If you touch something that is warmer than your body you feel warmer because heat is moving from the hot object into your body. That is conductive heat transfer.
Now what happens when you are next to an object long enough to equalize the temperatures? Let’s go back to the bed scenario. When you get in bed it feels cool. Right away your bed starts to absorb the heat your body is generating.
The problem arises when the material that is absorbing your body heat is no longer able to absorb more heat. At that point your body starts to look for other methods of cooling.
In Your Bed
Heat transference by radiation will be absorbed by your bed. Radiant energy will be absorbed by the bed material until you reach a point at which the bed can no longer absorb more radiant heat.
Conductive heat transference, which is the heat that is transferred when you touch something, will be absorbed into your bed as well. This heat will also accumulate until your bed can no longer absorb any more.
Convection, which is the transference of heat by conveying that heat, in this case to air, is only effective when you can generate air movement within that space. Heat will transfer from your body to the air around you and then move off, either by a buoyancy difference or by induced movement.
What this means is that when air gets warmer it tends to rise and be replaced by cooler air. If the air is induced to move, like standing in a breezeway or next to a fan, hot air will move off giving fresh cooler air an opportunity to absorb more heat.
Being that you are in a bed, covered with sheets, and the air surrounding you is trapped, the fresh air required for convection to work properly, is not there.
But if that was case wouldn’t everyone sweat in bed? The short answer is no.
Equilibrium
There is a point where you reach equilibrium between heat absorption of your bed and heat generation of your body. This is the point where your bed is able to absorb enough heat to keep you comfortable. This is your comfort zone.
Let’s say your body generates 200 units of heat every minute. Now equilibrium is where the bed is able to absorb 200 units of heat each minute. At that point you can sleep comfortably; you are in an equalized state.
Now let’s say your bed is absorbing 250 units of heat every minute, but you are only generating 200 units of heat each minute. In this situation you will have a cold bed. This is not equilibrium.
If your bed can only absorb 150 units of heat each minute and you are generating 200 units of heat, then you have a hot bed. This again is not equilibrium.
Those Hot Bodies
If you are suffering from night sweats, your body is generating heat at different levels during the night. Although you are able to get into bed and it feels nice and cool, that feeling fast evades you. For those of us that have night sweats, we are dealing with a body that generates heat at varying temperatures all night long.
As with the previous mentioned equalized bed scenario, when you first get into bed your body is generating 200 units of heat each minute. Your bed is absorbing 200 units of heat each minute. You are in equilibrium, all is well. But then your body temperature rises.
Now your body is generating more than 200 units of heat each minute and your bed can’t keep up. If you are generating 250 units of heat each minute and the bed can only absorb 200 units of heat, where will those extra 50 units of heat go? They will go nowhere. They start to accumulate and buildup between the sheets.
This buildup of extra heat starts a downhill roll right to sweating. Once the extra heat starts to accumulate, and your body starts to get warmer, the only method left for cooling your body is sweating.
Turning Off The Oven
So the question is how do you solve the problem of excessive heat that leads to sweating. In order to do this you must look at the three main methods of cooling and see what you can work with to keep your body cool.
Radiation is the first method used by your body to eliminate heat. Yet that heat is much like heat transferred by conduction. It is absorbed into the bed and will contribute to night sweats. This heat must be drawn out of your bed.
Conduction is the second method of cooling your body. The only way to utilize this is to make the bed much cooler. Conduction is the method that doctors are prescribing when they tell you to keep your room cooler.
Keeping your room cooler will help your bed absorb more radiant heat and conductive heat but relying on conduction can be cumbersome. The cost associated with hyper cooling a room and the effect extra coolness has on other members of the house are just two reasons to look else ware.
Remember the bed that absorbs 250 units of heat is a cold bed when you are only generating 200 units of heat.
The third method of keeping you body cool is to utilize convection. But convection requires air movement to be effective. So how do you move air when you are between the sheets?
There are several things you can do move the air between your sheets. One is to kick off the covers and let some cool air in. The other is to raise the sheets and allow some air to flow in. When you lower the sheets the hot air flows out, The other option is to use a fan made specifically for this situation.
Keeping Your Cool
With all the methods stated above you will find that moving air between your sheets and around your body is actually a simple, cost effective way to keep your body and your bed, cool.
A special fan that can generate a light breeze between your sheets will be more effective then lowering your thermostat by six to eight degrees. This type of cooling system will also benefit you in the following ways.
* Much lower cost of cooling then Air Conditioning.
* Variable speed under your pillow
* Can be directed at a single user
* Evacuates stagnant, humid air trapped between your sheets
* Keeps you and your bed at a constant temperature
A system like this will generate a light breeze that will travel between your sheets along your body and push the hot air out of your bed. It will also eliminate the heat that has been building-up within your bed.
Any conductive heat or radiant heat that has built-up in your bed will be eliminated with the breeze. Neither your body nor your bed will accumulate that extra that typically awakens you at night. .
The extra body heat that you generate during the night, will be quickly moved out from between your sheets. This simple breeze will keep your body from ever reaching the point at which it starts to sweat. This is the most effective method of dealing with night sweats when you look at it from a thermal dynamics point of view.
There are other methods of dealing with the effects of night sweats, like wicking pajamas and absorbent sheets, but those are not dealing with the problem at hand. They are only dealing with the aftermath of the problem. They are collecting sweat. What you want to do is keep from sweating all together.
Kurt Tompkins
http://www.articlesbase.com/health-articles/why-night-sweats-occur-and-how-to-stop-them-120604.html
Jan 29
Santa Fe homes have some of the nation’s most advanced cooling systems, thanks to the region’s hot, dry summers. Central Air Conditioning is common here, but homeowners and builders who want to reduce electricity costs and environmental impact have turned to other cooling methods to get the most bang for their buck. One of the most popular and efficient home cooling systems in the Santa Fe region is evaporative cooling, a combination of ancient techniques and the latest in air flow engineering. Homes in Santa Fe use a variety of different types of evaporative cooling methods to keep their home comfortable all summer, and reduce air dryness in the winter heating seasons.
Evaporative coolers employ the simple principle of air humidity to reduce overall home temperature. They are typically comprised of a metal or plastic box on the outside of the house, with vented sides for air intake, a centrifugal fan or “blower,” an electric motor with pulleys, and a water pump to wet the evaporative cooling pads. In cooling homes, they simply draw air through the vents, which pass through the damp pads and out into the rest of the home. Because they draw air from outside the building, evaporative coolers must be accompanied by vents to allow air to move from inside to outside. The venting system allows for 15 or more air changes per hour within a home, which dramatically reduces air age.
Common evaporative cooling methods include direct evaporative cooling, indirect evaporative cooling, and two stage evaporative cooling. Direct evaporative cooling is the same as described above, with an air intake sucking moistened air inside, pushing it through the building, and later venting it outside the building. Indirect systems work by the same process, except without air passing freely through the building. They contain the cooled air as it passed through the building in some type of heat exchanger, thus making the building cooler without increasing the humidity. Two-stage evaporative cooling pre-cools the air in a heat exchanger before sending it through the wet cooling pads. This results in less humidity throughout the building, because cooler air doesn’t hold as much moisture as untreated warm air.
Another advantage of evaporative coolers is their cheaper installation cost - they usually cost one quarter to an eighth as much as much as air conditioners to install, and require much less energy to operate. Many Santa Fe real estate buyers and sellers have saved a lot of money by learning the basics of evaporative cooling.
Jason Couillard
http://www.articlesbase.com/real-estate-articles/a-cheaper-way-to-cool-your-santa-fe-home-267853.html
Jan 28
Hey everyone. When I was looking to join the military, there was only the marines and army nearby, so I thought. I finally found out there is a air force recruiting station near us. With that said, the more I read about the air force compared to the army, the more I want to switch over. Is there any way I can switch over to the air force from the army before I go to meps the second time and ship off to basic? I leave March 8th. Thanks.
I just hear the living conditions are much better when you’re in the air force, and I’m a technology kind of guy.
Go straight to the air force recruiter and ask them, things have changed, a lot in the past few years and the past few months, I doubt anyone except a recruiter can give you a straight answer
Jan 28
I’m 27 years old, married for 3 years, no kids yet (but want one within the next year and a half), and am curious about joining a branch of the military. Mainly what sparks my interest in it is the confidence building and persona strengthening which joining the ranks can do for a person. I feel that strengthening as a person will help my relationships: marriage, social and parental (in the future), and I need some sort of conditioning as such. So I thought of the military.
I have already completed a 4 year college, so I am not in need of secondary education, unless it applied to flight school or something like that. I don’t know how it works with the Air Force or the Navy or Marines. I’m kind of naive and kiddish and I feel I need something to spark a reality for me, to help me become more responsible with adult realities in the world. Am I thinking the wrong thing here? Is the military out of my league? Does it required too many years’ commitment or would it interfere with my family plans in the near future?
Aim High
The Marines are not Mentally stable much less family friendly. From what i gather reading your post, I’d say You need to look in to the Air Force Reserves or Air National Guard maybe even Army National Guard. It all depends on what your hubby does for a living, rather you want to move, and what your degree is in.
Unless your hubby is a Ex-convict, who makes a living smuggling guns, drugs, or illegal aliens, has a drinking problem, and anger management issues. In that case you’d love the Marines.
