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Thursday, 5 September 2013

Noise Pollution?

What is Noise Pollution?

Sound is essential to our daily lives, but noise is not. Noise is generally used as an unwanted sound, or sound which produces unpleasant effects and discomfort on the ears.

Sound becomes unwanted when it either interferes with normal activities such as sleeping, conversation, or disrupts or diminishes one’s quality of life. Not all noise can be called noise pollution. If it does not happen reqularly, it may be termed as 'Nuisance'

Scientists also believe that its not only humans who are affected. For example, water animals are subjected to noise by submarines and big ships on the ocean, and chain-saw operations by timber companies also create extreme noise to animals in the forests.

Generally, noise is produced by household gadgets, big trucks, vehicles and motorbikes on the road, jet planes and helicopters hovering over cites, loud speakers etc.

NOISE POLLUTION:

Noise (or sound) is measured in the units of decibels and is denoted by the dB. Noise which is more than 115 dB is tolerant. The industrial limit of sound in the industries must be 75 dB according to the World Health Organization.

Noise is considered as environmental pollution, even though it is thought to have less damage on humans than water, air or land pollution. But people who are affected by severe noise pollution know that it is a massive issue that needs attention.

What are the sources of noise pollution?

Noise can come from many places. Let us see a few good sources:

Household sources:
Gadgets like food mixer, grinder, vacuum cleaner, washing machine and dryer, cooler, air conditioners, can be very noisy and injurious to health. Others include loud speakers of sound systems and TVs, ipods and ear phones. Another example may be your neighbor’s dog barking all night everyday at every shadow it sees, disturbing everyone else in the apartment.

Social events:
Places of worship, discos and gigs, parties and other social events also create a lot of noise for the people living in that area. In many market areas, people sell with loud speakers, others shout out offers and try to get customers to buy their goods. It is important to note that whey these events are not often, they can be called 'Nuisance' rather than noise pollution.

Commercial and industrial activities:
Printing presses, manufacturing industries, construction sites, contribute to noise pollutions in large cities. In many industries, it is a requirement that people always wear earplugs to minimize their exposure to heavy noise. People who work with lawn mowers, tractors and noisy equipment are also required to wear noise-proof gadgets.

Transportation:
Think of aero planes flying over houses close to busy airports like Heathrow (London) or Ohare (Chicago), over ground and underground trains, vehicles on road—these are constantly making a lot of noise and people always struggle to cope with them.

What can be called a 'Nuisance'?

Nuisance is usually used to describe an activity or condition that is harmful or annoying to others (e.g., indecent conduct, a rubbish heap or lot of birds making their nests in someones roof to the extent that they cause problems)

A few good examples of nuisance include:
Barking dogs
Building and construction site noise (please note however that noisy Work is permitted between 8am and 6pm Monday to Friday, and8am to 1pm on Saturdays)
DIY noise during anti-social hours
Burglar / car alarms
Noisy deliveries at unreasonable hours
Parties, Nightclubs and pubs
Loud music / television / computer games
Industrial processes (dry cleaners, factories etc)
Kitchen extract / air conditioning units
Places of worship
Open-air event and street performers.

A public nuisance is an unreasonable interference with the public's right to property. It includes conduct that interferes with public health, safety, peace or convenience. This is a term that is mostly used in law and court rooms.

Statutory Nuisance can also be used for instances including the adverse effects of artificial light, dust, odour and insects.

Generally, all the above can mean different things to different people. For example, if your neighbor is a lover of cats, and you are not, it will not be long before you have problems if the cats keep coming to your balcony. Another cat lover may find this exciting and will be very happy with that.

So you see, usually, the term 'Nuisance' is used in relation to the average or generally acceptable conditions of a place or group of people.

Effects of noise pollution

Generally, problems caused by noise pollution include stress related illnesses, speech interference, hearing loss, sleep disruption, and lost productivity. Most importantly, there are two major effects we can look at:

Hearing
The immediate and acute effect of noise pollution to a person, over a period of time, is impairment of hearing. Prolonged exposure to impulsive noise to a person will damage their eardrum, which may
result in a permanent hearing.

Effects on general health
Health effects of noise include anxiety and stress reaction and in extreme cases fright. The physiological manifestations are headaches, irritability and nervousness, feeling of fatigue and decreases work efficiency. For example, being pounded by the siren of fire fighters, police or ambulance in your city all night everyday leave people (especially elderly people) stresses and tired in the morning.

Its is worth noting that these effects may not sound troubling, but the truth is, with time, the consequences can be very worrying.

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Books

P - Productivity S - Speed R - Relevancy
Price: $20.00 USD. Approx. 22,870 words. Language: English. Published on August 23, 2013. Category: Essay.
How to Take Off Your Professional Career from an Average to Exceptional with the Hidden PSR in You. A Book By working CEO and Manager with Day to day and live Examples How to Fight with Global Recession. By Shekhar Gupta Surbhi Maheshwari

Published: Aug. 23, 2013
Words: 22,870 (approximate)
Language: English
ISBN: 9781301432448

Be an Aviator Not a Pilot

is a story of Pilots in Aviation who are unable to cope. This is not a book to teach you how to get into an Aviation School or even how to live like a Pilot. In fact, it describes how one can become a Successfull Aviator not just an Airplane Driver [ So called Pilot ] with very small changes in life. Also Why abroad trained Pilots are better Aviator and Why FAA, CASA, CAAP, CAA are better civil Aviation Authority then DGCA.
by
Shekhar Gupta
Ankisha Awasthi

Be An Aviator not A Pilot
Price: $1.99 USD. Approx. 4,750 words. Language: English. Published on July 24, 2013. Category: Fiction. As A Fact Out Of Every 1000 Pilots Only 1 Pilot Becomes An Airline Pilot, The Book Is All About Those 999 Pilots Only.

PilotsCareerGuide

Pilot’s Career Guide
Price: $20.00 USD. Approx. 25,040 words. Language: English. Published on July 13, 2013. Category: Nonfiction.
International Airline Pilot’s Career Guide Learn Step By Step How to Become an International Airlines Pilot By Shekhar Gupta And Niriha Khajanchi

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Cabin Crew Career Guide

Essay » Literature

Published: Aug. 26, 2013
Words: 2,160 (approximate)
Language: English
ISBN: 9781301001965

Introduction to Forest Preservation

FOREST PRESERVATION:

Environmental activists consider forests as one of the top 5 natural resources on earth. This is rightly so, and today, we shall look at how wonderful our forests have been to us, and why we should immediately stop its' destruction.

There is more to forests than just a massive collection of trees. It is a natural, complex ecosystem, made up of a wide variety of trees, that support a massive range of life forms.

Quiet apart from trees, forests also include the soils that support the trees, the water bodies that run through them and even the atmosphere (air) around them. Forests of the world are a natural wonder that humans have sadly taken for granted.

Forests come in many sizes and forms. For example, the piece of land with huge trees and many animals, birds and water bodies running through it in a part of Kenya can be called a forest. In the same way, the large belt of thick, evergreen trees running from Peru to Brazil (called the Amazon Rain Forest) is also a forest. A good example is the Amazon Rain Forest.

It is estimated that two-thirds of the world's forest is currently distributed among 10 countries:

Forests are hugely important for life on earth. This is because it serves as an ecosystem, and sustains life for millions of animals, birds and animals that live in the rivers and streams running through these forests. It also does a lot of good to the atmosphere in climate control, as well as supplying oxygen for human sustenance.

In the next pages, we shall look at the types and importance of forests, the problem of deforestation and its effects, as well as what we can do minimise the consequences.

Types of Forests

Tropical rainforests
Hugely dense, lush forest with canopies preventing sunlight from getting to the floor of the forest.
All year high temperatures and abundant rainfall.
Located near the equator.
A vital storehouses of biodiversity, sustaining millions of different animal, bird, algae and fish species.

Sub-tropical forests
Located at the south and north of the tropical forests.
Trees here are adapted to resist the summer drought.

Mediterranean forests
Located at the south of the temperate regions around the coasts of the Mediterranean, California, Chile and Western Australia.
The growing season is short and almost all trees are evergreen, but mixed hardwood and softwood.

Temperate forests
Located at Eastern North America, northeastern Asia, and western and eastern Europe.
Mix of deciduous and coniferous evergreen trees.
Usually, the broad-leaved hardwood trees shed leaves annually.
There are well-defined seasons with a distinct winter and sufficient rainfall.

Coniferous forests
Located in the cold, windy regions around the poles.
They come in both hardwoods and conifers.
The hardwoods are deciduous.
The conifers are evergreen and structurally adapted to withstand the long drought-like conditions of the long winters.

Montane forests
Known as cloud forests because they receive most of their precipitation from the mist or fog that comes up from the lowlands.
Usually found in high-elevation tropical, subtropical and temperate zones.
Plants and animals in these forests are adapted to withstanding the cold, wet conditions and intense sunlight.
Trees are mainly conifers.

Plantation forests
Has around 7% of global forest cover (140 million hectares).
Produces more sustainable timber and fibre than natural forests.
Plantations produce around 40% of industrial wood.
Plantation forests are on the increase.

The layers of a typical rain forest

Now, we shall look at the basic structure (layers) of a typical forest.

Let's take the Rainforest as an example... There are 4 major layers including:

The Emergent Layer (A):
This layer is very sunny because it is the very top and only the tallest trees reach this level. It is also known as the overstory.
Who lives here? Birds, butterflies, small monkeys, bats, snakes and bugs.

The Canopy Layer (B):
This is the thickest layer and much of the rain is stopped by the thick foliage. Most trees in the forest grow to this height. There are plants that grow in the canopy layer whose roots don't reach the ground. These are called air plants.
Who lives here? Birds, monkeys, frogs, and sloths, lizards, snakes and many insects.

The Understory (C):
This layer has many vines, dense vegetation but not much sunlight as it is all blocked by the canopy.
Who lives here? Birds, butterflies, frogs and snakes.

The Forest Floor (D):
This layer is dark, damp, full of many dead leaves, twigs and dead plants. It is usually clear of vegetation, with little or no winds and rains reaching there. The forest floor is dark due to the trees above stopping the sunlight from entering the forest. It is estimated that only 2% of the sunlight actually reaches the floor.
Who lives here? Jaguars in South America, gorillas,
leopards in Africa, tapirs, tigers and elephants in Asia.

What is the meaning of forestry?

We learned about the complex interaction of climate, soils and rocks, water, animals, (including insects and fungi) and plants as the defining elements of a natural forest.

Forestry is the study of this complex interaction, the management of the various components of the forest, the preservation of its natural balance (of forests and the life forms they support) as well as the care of it to ensure its wellbeing.

Good forestry programs also makes it possible for humans to get some economic value from it, without hurting the forests in anyway. This way of using the forest is known as Sustainable Forestry.

Sustainable Forestry
In sustainable forests, efforts are put into replacing almost all the resources we get from the forests, whiles extra care is taken to ensure that there is very little damage to wildlife and the natural environment.

Example: only old trees may be cut down, allowing younger trees to grow to ensure continuity and trees are planted to replace the ones cut down.

Unfortunately, environmental issues cannot be separated from politics and economics (people’s life) This is why effective sustainable forestry comes in two approaches. These are:

Forests and Forests related Industries
Here, the attention is on the natural resource itself and the timber companies that harness resources directly from the forests. In this approach, there are usually very strict rules and consequences with the way resources are extracted from that forest. It is usually enforced by laws, hefty fines and effective monitoring efforts.

This means items made from resources that come from forests will cost a lot in the shops, so consumers also need to be prepared.

Consumer behavior
Here, campaigns are developed to educate consumers (industries and individuals including you) on the value of forests resources and the dangers they face. Efforts are directed to make people become more environmentally friendly. Example, people are encouraged to recycle more, to use paper products from recycled pulp, and to encourage everyone to join the fight to save our forests.

Books by AeroSoft

Books

Published: Aug. 23, 2013
Words: 22,870 (approximate)
Language: English
ISBN: 9781301432448

PilotsCareerGuide

https://www.smashwords.com/books/view/336260

Cabin Crew Career Guide

Essay » Literature

Published: Aug. 26, 2013
Words: 2,160 (approximate)
Language: English
ISBN: 9781301001965

Triangle Congruence - ASA and AAS

We've just studied two postulates that will help us prove congruence between triangles. However, these postulates were quite reliant on the use of congruent sides. In this section, we will get introduced to two postulates that involve the angles of triangles much more than the SSS Postulate and the SAS Postulate did. Understanding these four postulates and being able to apply them in the correct situations will help us tremendously as we continue our study of geometry. Let's take a look at our next postulate.

ASA Postulate (Angle-Side-Angle)

If two angles and the included side of one triangle are congruent to the corresponding parts of another triangle, then the triangles are congruent.

In a sense, this is basically the opposite of the SAS Postulate. The SAS Postulate required congruence of two sides and the included angle, whereas the ASA Postulate requires two angles and the included side to be congruent. An illustration of this postulate is shown below.

Exercise 1

Solution:

Let's start off this problem by examining the information we have been given. Since segments PQ and RS are parallel, this tells us that we may need to use some of the angle postulates we've studied in the past. Now, let's look at the other piece of information we've been given. We know that ?PRQ is congruent to ?SQR. Let's further develop our plan of attack.

We have been given just one pair of congruent angles, so let's look for another pair that we can prove to be congruent. We can say ?PQR is congruent to ?SQR by the Alternate Interior Angles Postulate. Recall, we can only use this postulate when a transversal crosses a set of parallel lines. In this case, our transversal is segment RQ and our parallel lines have been given to us.

Now that we've established congruence between two pairs of angles, let's try to do something with the included side. The included side is segment RQ. By using the Reflexive Property to show that the segment is equal to itself, we now have two pairs of congruent angles, and common shared line between the angles. Our new illustration is shown below.

We conclude our proof by using the ASA Postulate to show that ?PQR??SRQ. Let's look at our two-column geometric proofthat shows the arguments we've made.

Aside from the ASA Postulate, there is also another congruence postulate that involves two pairs of congruent angles and one pair of congruent sides. Let's take a look at this postulate now.

AAS Postulate (Angle-Angle-Side)

If two angles and a non-included side of one triangle are congruent to the corresponding parts of another triangle, then the triangles are congruent.

In order to use this postulate, it is essential that the congruent sides not be included between the two pairs of congruent angles. If the side is included between the angles, we would actually need to use the ASA Postulate. The correct use of theAAS Postulate is shown below.

Let's use the AAS Postulate to prove the claim in our next exercise.

Exercise 2

Solution:

Before we begin our proof, let's see how the given information can help us. We have been given that ?NER??NVR, so that is one pair of angles that we do not need to show as congruent.

Now, we must decide on which other angles to show congruence for. We may be able to derive a key component of this proof from the second piece of information given. Since segment RN bisects ?ERV, we can show that two congruent angles are formed. By the definition of an angle bisector, we have that ?ERN??VRN.

The only component of the proof we have left to show is that the triangles have congruent sides. Luckily for us, the triangles are attached by segment RN. So, we use the Reflexive Property to show that RN is equal to itself. Let's look at our new figure.

Finally, by the AAS Postulate, we can say that ?ENR??VNR. Note that our side RN is not included. If it were included, we would use the ASA Postulate to prove that the triangles are congruent. The two-column proof for this exercise is shown below.

Best Teacher I Ever Had by David Owen

Mr. Whitson taught sixth-grade science. On the first day of class, he gave us a lecture about a creature called the cattywampus, an ill-adapted nocturnal animal that was wiped out during the Ice Age. He passed around a skull as he talked. We all took notes and later had a quiz.

When he returned my paper, I was shocked. There was a big red X through each of my answers. I had failed. There had to be some mistake! I had written down exactly what Mr. Whitson said. Then I realized that everyone in the class had failed. What had happened?

Very simple, Mr. Whitson explained. He had made up all the stuff about the cattywampus. There had never been any such animal. The information in our notes was, therefore, incorrect. Did we expect credit for incorrect answers?

Needless to say, we were outraged. What kind of test was this? And what kind of teacher?

We should have figured it out, Mr. Whitson said. After all, at the every moment he was passing around the cattywampus skull (in truth, a cat's), hadn't he been telling us that no trace of the animal remained? He had described its amazing night vision, the color of its fur and any number of other facts he couldn't have known. He had given the animal a ridiculous name, and we still hadn't been suspicious. The zeroes on our papers would be recorded in his grade book, he said. And they were.

Mr. Whitson said he hoped we would learn something from this experience. Teachers and textbooks are not infallable. In fact, no one is. He told us not to let our minds go to sleep, and to speak up if we ever thought he or the textbook was wrong.

Every class was an adventure with Mr. Whitson. I can still remember some science periods almost from beginning to end. On day he told us that his Volkswagon was a living organism. It took us two full days to put together a refutation he would accept. He didn't let us off the hook until we had proved not only that we knew what an organism was but also that we had the fortitude to stand up for the truth.

We carried our brand-new skepticism into all our classes. This caused problems for the other teachers, who weren't used to being challenged. Our history teacher would be lecturing about something, and then there would be clearings of the throat and someone would say "cattywampus.''

If I'm ever asked to propose a solution to the problems in our schools, it will be Mr. Whitson. I haven't made any great scientific discoveries, but Mr. Whitson's class gave me and my classmates something just as important: the courage to look people in the eye and tell them they are wrong. He also showed us that you can have fun doing it.

Not everyone sees the value in this. I once told an elementary school teacher about Mr. Whitson. The teacher was appalled. "He shouldn't have tricked you like that,'' he said. I looked that teacher right in the eye and told him that he was wrong.

Books by AeroSoft