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Garbage In，Garbage Out
There are many ways of obtaining an understanding of
people's behaviour. One of these
is to study the objects discarded by a community}objects used in
daily lives. The
study of the refuse of a society is the basis for the science of
archaeology in which
the lives and behaviour of past societies are minutely examined.
.Some recent studies
have indicated the degree to which rubbish is socially defined.
For several years the University of Arizona,, USA has been
running a Garbage! Project,
in which garbage is collected, sorted out and noted. It began in
1973with an
arrangement whereby the City of Tucson collected for analysis
garbage from randomly
selected households in designated census collection districts. Since
then the
researchers have studied other cities both in the USA and Mexico,
refining their
techniques and procedures in response to the challenges of
validating and
understanding the often unexpected results they have obtained.
Garbage is sorted
according to an extremely detailed schedule, a range of data for
each item is recorded
on a standardised coding form, and the researchers cross-tabulate
their findings
with information from census and other social surveys.
This Project arose out of courses designed to teach
students at the University the
principles of archaeological methodology and to sensitise them to
the complex and
frequently surprising links between cultural assumptions and
physical realities.
Often a considerable discrepancy exists between what people say they
do -or even
think they do -and what they actually do. In one Garbage Project
study none of the
Hispanic (Spanish-speaking)women in the sample admitted to using as
much as a single
serving of commercially-prepared baby food, clearly reflecting
cultural
expectations about proper mothering. Yet garbage from the Hispanic
households with
infants contained just as many baby food containers as garbage from
non-Hispanic
households with infants.
The Project leaders then decided to look not only at what
was thrown away, but what
happened to it after that. In many counties waste is disposed of in
landfills, the
rubbish is compacted and buried in the ground. So in 1987,the
Project expanded its
activities to include the excavation of landaus across the United
States Y-and Canada.
Surprisingly, no-one had ever attempted such excavations before.
The researchers discovered that far from being sites of
chemical and
biologicalactivity,theinteriorsofwastelandfillsareratherinactive,with
the
possible exception of those established in swamps. Newspapers buried
20or more years
previously usually remained perfectly legible, and a remarkable
amount of food
wastes of similar age also remained intact.
While discarded household products such as paints,
pesticides, cleaners and
cosmetics result in a fair amount of hazardous substances being
contained in
fear, provided that a landfills properly sited and constructed.
Garbage projected
researchers have found that the leadut6donotmigratefar,and tend to
get absorbed by
the other materials in the immediate surrounds.'
The composition of landfills is also strikingly different
from what is
commonly believed. In a 1990 US survey people were asked whether
particular
items were a major cause of garbage problems. Disposable nappies
(baby
diapers) were identified as a major cause by41per cent of the survey
respondents, plastic bottles a by 29 per cent, all forms of paper by
six
per cent, and construction debris by zero per cent. Yet Garbage
Project
data shows that disposable nappies make up less than two per cent of
the
volume of landfills and plastic bottles less than one per cent. On
the other
hand, over 40 per cent of the volume of landfills is composed of
paper and
around 12 per cent is construction debris.
Packaging -- the paper and plastic wrapping around goods
bought -- has
also been seen as a serious cause of pollution. But while some
packaging
is excessive, the Garbage Project researchers note that most
manufacturers use as little as possible, because less is cheaper.
They
also point out that modem product packaging frequently functions
reduce
the overall size of the solid-waste stream.
This apparent paradox is illustrated by the results of a
comparison
of garbage from a large and socially diverse sample of homeholds in
Mexico City with a similarly large and diverse sample m three United
States cities. Even after correcting for differences in family size,
US households generated far less garbage than the Mexican ones.
Became
they are much more dependent on processed and packaged foods than
Mexican households, US homeholds produce much less food debris.(And
most of the leaves, husks, etc. that the US processor has removed
from
the food can be used in the manufacture of other products, rather
than
entering the waste steam as is the likely fate with fresh produce
purchased by households.)
One criticism made of Western societies is that the people
are wasteful
and throw things away while they are still useable. This, however,
does
not seem to be true. Garbage Project data showed that furniture and
consumer appliances were entering the solid waste stream at a rate
very
much less than would be expected from production and service-life
figures. So the researchers set up a study to track the fate of such
item and thus gained an insight into the huge informal and
commercial
trade in used goods that rarely turns up in official calculations
and
statistics.
The Garbage Project's work shows how many misconceptions
exist about
garbage. The researchers are therefore critical of attempts to
promote
one type of waste management, such as source reduction or recycling,
over others, such as incineration or landfilling. Each has its
advantages and disadvantages, and what may be appropriate for one
locality may not be appropriate for another.
Glossary: Leachate: water carrying impurities which has filtered
through the soil
The Garbage Project
started in 1973
first studied garbage in the city of (29) since then has studied
it in other cities in USA and (30)
method: garbage collected and sorted, the information noted on
(31)
finding compared with (32) and other social surveys.
reason for Project show students the (33) of archaeological (34)
from 1987 Garbage Project studied (35)in USA and CANADA.
Keys:29 Tucson 30 Mexico 31 standardised coding form 32 census
33 principles 34 methodology 35 landfills
MISCONCEPTIONS COUNTERARGUMENTS
II: Household items, like A:40% of landfills is
paper
disposable nappies ,are a F: disposable nappies make
up
major cause of garbage less than 2% of landfills
problems.
Counter arguments for Misconception II: A& F
MISCONCEPTIONS COUNTERARGUMENTS
III: packaging is wasteful, and D: processing and packaging
cause excess garbage. cuts down on other
garbage
K:
manufacture cut their costs by
using as
little packaging as
possible
Counter arguments for Misconception II: D& K
MISCONCEPTIONS COUNTERARGUMENTS
I: landfills are dangerous B perishable items are
often
because they are full of germs almost uncharged, even
and chemicals after long periods
of time
H chemicals
do not spread far
in
landfills
Example
Counter argument for Misconception I: B&H
MISCONCEPTIONS COUNTERARGUMENTS
IV: Western societies waste J there are many businesses
many useable items. that collect and resell
things
people no
longer want
L household
goods constituted a smaller than excepted part of solid waste
Counter
argument for Misconception I: J&L
GLASS
CAPTURING THE DANCE OF LIGHT
Glass, in one form or another, has long been in noble service
to humans. As one of the most
widely manufactured materials, and certainly the most versatile. it
can be as imposing as a
telescope mirror the width of a tennis court or as small and simple
as a marble rolling across dirt.
The uses of this adaptable material have been broadened dramatically
by new technologies: glass
fibre optics - more than eight million miles -- carrying telephone
and television signals across
nations; glass ceramics serving as the nose cones of missile and as
crowns for teeth; tiny glass
beads taking radiation doses inside the body to specific organs;
even a new type of glass fashioned
of nuclear waste in order to dispose of that unwanted material.
On the horizon are optical computer. These could store
programs and process information by
means of light -- pulses from tiny lasers -- rather than electrons.
And the pulses would travel over
glass fibres, not copper wire. These machines could function
hundreds of times faster than today's
electronic computers and hold vastly more information. Today fibre
optics arc used to obtain a
clearer image of smaller and smaller objects than ever before - even
bacterial viruses. A new
generation of optical instruments is emerging that can provide
detailed imaging of the inner
workings of cells. It is the surge in fibre optic use and in liquid
crystal displays that has set the U.S.
glass industry (a 16 billion dollar business employing some 150,000
workers) to building new
plants to meet demand.
But it is not only in technology and commerce that glass
has widened its horizons. The use of
glass as art, a tradition going back at least to Roman times, is
also booming. Nearly everywhere, it
seems, men and women are blowing glass and creating works of art..
"I didn't sell a piece of glass
until 1975," Dale Chihuly said, smiling, for in the 18 years
since the end of the dry spell, He has
become one of the most financially successful artists of the 20th
century. He now has a new
commission -- a glass sculpture for the headquarters building of a
pizza company - for which his
fee is half a million dollars.
But not all the glass technology that touches our lives is
ultra-modern. Consider the simple light
bulb; at the turn of the century most light bulbs were hand blown,
and the cost of one was
equivalent to half a day's pay for the average worker. In effect.
the invention of the ribbon
machine by corning in the 1920s lighted a nation. The price of a
bulb plunged. Small wonder that
the machine has been called one of the great mechanical achievements
of all time. Yet it is very
simple: a narrow ribbon of molten glass travels over a moving belt
of steel in which there are
holes. The glass sags through the holes and into waiting moulds.
Puffs of compressed air then
shape the glass. In this way, the envelope of a lights bulb is made
by a single machine at the rate
of 66,000 an hour, as compared with 1,200 a day produced by a team
of four glassblowers.
The secret of the versatility of glass lies in its interior
structure. Although it is rigid, and thus like a
solid, the atoms are arranged in a random disordered fashion,
characteristic of a liquid. In the
melting process, the atoms in the raw materials are disturbed from
their normal position in the
molecular structure; before they can find their way back to
crystalline arrangements the glass
cools. This looseness in molecular Structure gives the material what
engineers call tremendous
"formability" which allows technicians to tailor glass to
whatever they need.
Today, scientists continue to experiment with new glass
mixtures and building designers test their
imaginations with applications of special types of glass. A London
architect, Mike Davies, sees
even more dramatic buildings using molecular chemistry of
"Glass is the great building material
of the future. the "dynamic skin "he said"Think of
glass that has been treated to react to electric
currents going through it. glass that will change from dear to
opaque at the push of a button, that
gives you instant curtains-Think of how the tall buildings in New
York could perform a symphony
of colours as the glass in them is made to change colours
instantly-'Glass as instant curtains is
available now, but the cost is exorbitant. As for the glass changing
colours instantly, that may
come true-Mike Davies'S vision may 'indeed be on the way to
fulfillment.
List of headings Answer
iii: What makes glass so adaptable X Everyday uses
of glass
Paragraph B viii
Exciting innovations in fibre
optics
Paragraph C i
Growth in the market for glass
crafts
Paragraph D ix
A former glass technology
Paragraph E iii
What makes glass so adaptable
Paragraph F vi
Architectural experiments with
glass
A if the uses exist today 9
dental fittings
B if the uses will exist in the future 10 optical
computers
C if the uses are not mentioned by the writer 11 sculptures
12 fashions
13 curtains
key:9A 10 B 11 A 12 C 13 A
Why some women cross the finish line ahead of men
A\ Women who apply for jobs in middle or senior management have a
higher success
rate than men. according to an employment survey, But of course far
fewer of them
apply for these positions. The study by recruitment consultants NB
Selection. shows
that while one in six men who appear on interview shortlists get
jobs. the figure
rises to one in four women.
B\ The study concentrated on applications for management
positions in the
$45,000 to $110,000 salary range and found that women are more
successful than men
in both the private and public sectors. Dr Elisabeth Marx from
London-based NB
Selection described the findings as encouraging for women. In that
they send a
positive message to them to apply for interesting management
positions But the
added. `We should not lose sight of the fact that significantly
fewer women apply
for senior positions in comparison with men.
C\ Reasons for higher success rates among women are difficult so
isolate. One
explanation suggested is that if a woman candidate manages to get on
a shortlist,
then she has probably already proved herself to be an exceptional
candidate
. Dr Marx said that when women apply for positions they tend to be
better qualified
than their male counterparts but are more selective and conservative
in their job
search. Women tend to research thoroughly before applying for
positions or attending
interviews. Men, on the other hand. seem to rely on their ability to
sell themselves
and to convince employers that any shortcomings they have will not
prevent them from
doing a good job.
D\ Managerial and executive progress made by women is confirmed by
the annual survey
of boards of directors carried out by Korn／Ferry／Carre /Orban
International. This
year the survey shows a doubling of the number of women serving as
non-executive
directors compared with the previous year, However, progress remains
painfully slow
and there were still only 18 posts filled by women out of a total of
354 non-executive
positions surveyed. Hilary Sears. a partner with Korn／Ferry. said,
`Women have
raised the level of grades we are employed in but we have still not
broken through
barriers to the top.
In Europe a recent feature of corporate life in the recession has
been the de-layering
of management structures. Sears said that this has halted progress
for women in as
much as de-layering has taken place either where women are working
or in layers they
aspire to. Sears also noted a positive trend from the recession,
which has been the
growing number of women who have started up on their own.
F\ ]In business as a whole, there are a number of factors
encouraging the prospect
of greater equality in the workforce. Demographic trends suggest
that the number
of women going into employment is steadily increasing. In addition a
far greater
number of women are now passing through higher education. making
them better
qualified to move into management positions.
D\ Managerial and executive progress made by women is confirmed by
the annual survey
of boards of directors carried out by Korn／Ferry／Carre /Orban
International. This
year the survey shows a doubling of the number of women serving as
non-executive
directors compared with the previous year, However, progress remains
painfully slow
and there were still only 18 posts filled by women out of a total of
354 non-executive
positions surveyed. Hilary Sears. a partner with Korn／Ferry. said,
`Women have
raised the level of grades we are employed in but we have still not
broken through
barriers to the top.
In Europe a recent feature of corporate life in the recession has
been the de-layering
of management structures. Sears said that this has halted progress
for women in as
much as de-layering has taken place either where women are working
or in layers they
aspire to. Sears also noted a positive trend from the recession,
which has been the
growing number of women who have started up on their own.
F\ ]In business as a whole, there are a number of factors
encouraging the prospect
of greater equality in the workforce. Demographic trends suggest
that the number
of women going into employment is steadily increasing. In addition a
far greater
number of women are now passing through higher education. making
them better
qualified to move into management positions.
G\ Organisations such as the European Women's Management
Development Network provide
a range of opportunities for women to enhance their skills and
contacts. Through
a series of both pan-European and national workshops and conferences
the barriers
to women in employment are being broken down. However, Ariane Bertho
in Antal,
director of the International Institute for Organisational Change of
Archamps in
France, said that there is only anecdotal evidence of changes in
recruitment patterns.
And she said, `It's still so hard for women to even get on to
shortlists-there are
so many hurdles and barriers. Antal agreed that there have been some
positive signs
but said `Until there is a belief among employers, until they value
the difference,
nothing will change.
EXAMPLE
Answer
The salary range studied in the
B
NB Seliction survey.
14 The drawbacks of current company
E
restructuring patterns
15 Associations that provide support for
G
professional women
16 The success rate of female job applicants
A
for management positions.
17 Male and female approaches to job applications
C
18 Reasons why more women are being
F
employed in the business sector
19 The improvement in female numbers
D
on company management structures
Population viability analysis
Part A
To make political decisions about the extent and type of
forestry in a region it
is important to understand the consequences of those decisions. One
tool for
assessing the impact of forestry on the ecosystem is population
viability analysis
(PVA). This is a tool for predicting the probability that a species
will become
extinct in a particular region over a specific period. It has been
successfully
used in the United States to provide input into resource
exploitation decisions
and assist wildlife managers and there is now enormous potential for
using
population viability to assist wildlife management in Australia's
forests.
A species becomes extinct when the last individual dies.
This observation is a useful
starting point for any discussion of extinction as it highlights the
role of luck
and chance in the extinction process. To make a prediction about
extinction we need
to understand the processes that can contribute to it and these fall
into four broad
categories which are discussed below.
Part B
A Early attempts to predict population viability were based on
demographic
uncertainty. Whether an individual survives from one year to the
next will largely
be a matter of chance. Some pairs may produce several young in a
single year while
others may produce none in that same year. Small populations will
fluctuate
enormously because of the random nature of birth and death and these
chance
fluctuations can cause species extinctions uncertainty of ability to
reproduce into
account, extinction is unlikely if the number of individuals in a
population is
above about 50 and the population is growing.
B Small populations cannot avoid a certain amount of inbreeding.
This is particularly
true if there is a very small number of one sex. For example, if
there are only 20
individuals of a species and only one is a male, all future
individuals in the species
must be descended from that one male. For most animal species such
individuals are
less likely to survive and reproduce. Inbreeding increases the
chance of extinction.
C Variation within a species is the raw material upon which natural
selection
acts. Without genetic variability a species lacks the capacity to
evolve and can
not adapt to changes in its environment or to new predators and new
diseases. The
loss of genetic diversity associated with reductions in population
size will
contribute to the likelihood of extinction.
D Recent research has shown that other factors need to be
considered. Australia's
environment fluctuates enormously from year to year. These
fluctuations add yet
another degree of uncertainty to the survival of many species.
Catastrophes such
as fire, flood. drought or epidemic may reduce population sizes to a
small fraction
of their average level. When allowance is made for these two
additional elements
of uncertainty the population size necessary to be confident of
persistence for a
few hundred years may increase to several thousand.
Example
Answer
28 Scientists are interested in the effect
YES
of forestry on native animals.
29 PVA has been used in Australia for many years
NO
30 a species is said to be extinct when only
NO
individual exists
31 Extinction is a naturally occurring phenomenon
NOT GIVEN
Processes
32 Paragraph A
vi
The haphazard nature of
reproduction
33 Paragraph B
iii An imbalance of the sexes
34 Paragraph C
i
Loss of ability to adapt
35 Paragraph D
ii Natural disasters
Environment Effects of Offshore Drilling and Production
A main public concern about petroleum exploration and production
seems to be that a blow-out
will cause a major oil spill.
Oil often exists in the subsurface at great pressure and, in the
early days, when
wells were drilled with only air or water in the hole, the oil could
rush into
and up the hole and "blow out"at the surface. For reasons
of economy and safety,
the early oilmen soon put a stop to that practice. Rotary drilling
technology
developed rapidly, including special drilling fluids with additives
to control
their density and consistency, and counterbalance the pressure of
inflowing oil
or gas. Modern drilling rigs are also fitted with blow-out
prevention controls_
complex systems of metal clamps and shutters which can be used to
seal the hole
if unexpected high pressures are encountered.
There can be no denying that major blow-outs still occur, and
cause loss of life
, as well as severe ecological trauma and economic loss.
Fortunately, the available
technology and proper precautions make them very rare events. Since
offshore
drilling commenced in Australia in 1965, there has not been a single
oil blow-out.
Six gas blow-outs occurred during that time-five in Bass Strait and
one in t
he Timor Sea. The Bass Strait blow-outs were all controlled
relatively quickly;
the Petrel well in the Timor Sea flowed gas for 15 months. Only
one well involve
d any spillage of oil, and the amount was negligible. It is a
comment on improving
technology and safety procedures that four of the incidents occurred
in the 960s,
one in 1971 and the last in 1984.
The statistics on oil spills from offshore exploration and
production in Australian
Commonwealth waters are shown in the table below. The total
spillage, over 26 years,
is roughly equivalent in size to a large backyard swimming pool. The
main spills
have actually occurred in the loading of fuel onto production
platforms: they had
nothing to do with the oilwell itself.
In addition to the oil spill issue, there are concerns about
other discharges form
the drilling and production facilities: sanitary and kitchen wastes,
drilling fluid,
cuttings and produced water.
Putrescible sanitary and kitchen wastes are discharged into the
ocean but must
be processed in accordance with regulations set by the Federal
government. This
material is diluted rapidly and contributes to the local food chain,
without any
risk of nutrient oversupply. All solid waste material must be
brought ashore.
The cuttings are sieved out of the drilling fluid and usually
discharged into the
ocean. In shallower waters they form a low mound near the rig; in
deeper water a
wider-spread layer forms, generally within one kilometre of the
drillsite, although
this depends on a number of factors. Some benthic (bottom-dwelling)
organisms
may be smothered, but this effect is local and variable, generally
limited to within
about 10O metres of the discharge point. Better-adapted organisms
soon replace
them and storm-driven wave activity frequently sweeps away the
material.
Drilling fluid is also discharged directly into the ocean. Most of
the common
constituents of water-based fluids used m Australia have low-to-nil
toxicity to
marine orzamsn1s.Some additives are toxic but are used m small
concentrations
and infrequently. The small amounts of heavy metals present are not
absorbed into
the bodies of marine organisms, and therefore it is unlikely that
they would pose
problem for animals higher up the food chain. Field studi6have shown
that dilution
is normally very rapid, ranging to 1,000-fold within 3 metres of the
discharge point.
At Rivoli-1 well in Exmouth Gulf, the input was chemically
undetectable 560 metres
away.
Oil-based drilling fluids have a more toxic component, and discharge
to the
marine environment is more significant. However, they are used only
rarely in
Australia, and the impact remains relatively local. At Woodside's
North Rankin
A Platform offshore Western Australia, the only facility currently
using oil-based
fluids, the discharge is diluted 2,000-fold within 1 kilometre
downcurrent,
and undetectable beyond 20O metres either side.
In the event of a discovery, the presence of a permanent
production facility and
the discharge of "produced water" are additional concerns.
Produced water is the
water associated with the oil or gas deposit, and typically contains
some petroleum,
dissolved organic matter and trace elements. Most produced water is
effectively
non-toxic but, even when relatively toxic, is quickly diluted to
background levels.
The impact occurs mainly within about 2O metres of the discharge
point, but is
observable in some instance for about 1 kilometre downcurrent.
Government
regulations limit the oil content allowed to be discharged, and the
produced water
is treated on the platforms to meet those specifications. The
discharge points are
carefully selected to maximize dispersion and dilution, and avoid
any parUC1liariy
sensitive local environments.
Ultimately the best test of the real environmental effect of
drilling and producing
operations may be the response of the environment to the fixed
production
platforms. In many areas the platforms quickly become artificial
reefs, with the
underwater supports of the platforms providing a range of habitats,
from sea-bottom
to surface, and quickly colonised by a wide range of marine plants
and animals.
Glossary: Cuttings: small pikes of rock broken off as the drill
cuts through the rock
Putrescible: able to decompose, rot, break down
SK-1 if the
statement refers to sanitary and kitchen wastes which decay
C if the statement
refers to cuttings
DW if the statement
refers to drilling fluid-water-based
DO if the statement
refers to drilling fluid-oil-based
PW if the statement
refers to produced water
21 The waste must not be discharged into the ocean
SK-2
22 The waste may curtain heavy metals and toxic additives
DW
23 This waste can be used as a food source by marine organisms
SK-1
Keeping Cut Flowers
While everybody enjoys fresh cut flowers around their house, few
people know how
to keep them for as long as possible. This may be done by keeping in
mind a few simple
facts.
An important thing to remember about cut flowers is that they are
sensitive to
temperature. For example, studies have shown that cut carnations
retain their
freshness eight times longer when kept at 12℃ than when kept at
26℃. Keeping
freshly harvested flowers at the right temperatures is probably the
most important
aspect of flower care.
Flowers are not intended by nature to live very long. Their
biological purpose is
simply to attract birds or insects, such as bees, for pollination.
After that, they
quickly wither and die. The process by which flowers consume oxygen
and emit carbon
dioxide, called respiration,generates the energy the flower needs to
give the flower
its shape and colour. The making of seeds also depends on this
energy. While all
living things respire, flowers have a high level of respiration. A
result of all
this respiration is heat, and for flowers, the level of he at
relative to the mass
of the flower is very high. Respiration also brings about the
eventual death of the
flower, thus the greater the level of respiration, the sooner the
flower dies.
How, then to control the rate at which flowers die? By controlling
respiration.
How is respiration controlled? By controlling temperature. We know
that respiration
produces heat, but the reverse is also true. Thus by maintaining low
temperatures,
respiration is minimised and the cut flower will age more slowly.
(Tropic
al flowers are an exception to this rule; they prefer warmer
temperatures.)
Cooler temperatures also have the benefit of preserving the water
content of the
flower, which helps to slow down ageing as well. This brings us to
another important
aspect of cut flower care: humidity. The average air-conditioned
room has a relative
humidity of 65%, which contributes to greater water loss in the
flower. Flowers are
less likely to dry out if humidity levels are 90_95%, but this may
be unrealistic
unless you live in the tropics or subtropics.
Yet another vital factor in keeping cut flowers is the quality of
the water in which
they are placed. Flowers find it difficult to `drink' water that is
dirty or otherwise
contaminated. Even when water looks and smells clean, it almost
certainly contains
bacteria and fungi that can endanger the flowers. To rid the water
of these unwanted
germs, household chlorine bleach can be used in small quantities. It
is recommended
that 15 drops of chlorine bleach (at 4% solution )be added to each
litre of water.
The water and solution should also be replaced each day.
When going to buy cut flowers, look for ones that have not been
kept (by the flower
shop) in direct sunlight or strong wind. If the flowers are not
freshly harvested,
ask whether they have been stored in a refrigerated coolroom.
1 The author of Keeping Cut Flowers believes flower care is
dependent on
three main factors. one of them is temperature. What are the other
TWO?
2 A DIFFERENCE OF 140C can extend the life of carnations by up to ()
times.
3 () and () are two aspects of a flower's appearance that depend on
respiration.
KEY:1 humidity AND water quality(either order) 2 8/eight 3 shape
AND colour(either order)
key:5 controlling temperature//maintaining low
temperatures//cooler temperatures
6 water content 7 age(more)slowly 8 tropical
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