the body.qxp

BIOMETRICS
THE BODY
THE BODY AS IDENTITY
Body averages
Biometrics makes use of the infinite variability of certain common characteristics
shared by everyone. If we did not all have two hands and ten fingers, we would not
have distinguishable fingerprints! And so before using what sets us apart, we have to
know what brings us together. What are the average proportions of the human body?
Measurement 1
Use a ruler to measure distance A (from your hip to the floor) and distance B
(from the top of your knee to the floor). With the help of a calculator divide A by
B. The average result is 1.86.
Measurement 2
Use a ruler to measure distance C (from your shoulder to the tip of your middle
finger) and distance D (from your shoulder to the tip of the elbow). With the help
of a calculator divide C by D. The average result is 1.65.
Measurement 3
The height of most people is 2.9 times the length of their thigh. To see how you
compare, measure distance E (from your knee to the rear of your buttocks).
Then divide your height by distance E.
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BIOMETRICS
THE BODY
THE BODY AS IDENTITY
Measuring the body
Taking measurements of the body has always fascinated scientists and artists
alike. Many have sought to define the "perfect man" or at least a man whose proportions are in harmony with his environment. Here are a few milestones in this
search for the ideal man, a search that is no longer the object of anthropometric
study today.
Ideal proportions
The ancient Roman architect and engineer Vitruvius asserted that a man with outspread arms and legs is simultaneously inscribed in a circle and a square -both perfect geometric figures- and that the navel is at the centre of the human body.
Centuries later, in 1489, Leonardo da Vinci corrected the Vitruvian theory after
having taking a great many measurements of the human body: the centre of the
human body is above the pubis if it is inscribed in a square and it is the navel if
it is inscribed in a circle. The organic is in agreement with the geometric: this is
the theory of divine proportion. The accuracy of da Vinci's illustration is still
recognized today.
Ideal average man
In 1848 the Belgian mathematician Adolphe Quételet presented his theory of the
ideal average man, each of whose physiological characteristics would be equal
to the average of those of the entire population. Every human being would thus
fall short of this ideal average man, like imperfect copies of this sculpture symbolising perfection.
Sculpture: warrior known as the "Borghese Gladiator," early 1st century BCE.
Modulor
Starting from the assumption that "nature is mathematical", the French architect Le Corbusier created Modulor en 1948. This tool for architect and engineer
was intended to define "an harmonic measure on a human scale that was applicable to architecture and mechanics". In his post-war output, Le Corbusier made
extensive use of the system to create harmonious proportions.
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BIOMETRICS
THE BODY
THE BODY AS IDENTITY
The size of the French
Human body measurements are of interest in science, to be sure, but also in a
variety of other fields, such as industrial design and the clothing industry, where
the body is of some importance.
Because the size of clothing designed in the past does not necessarily correspond
to customers today, the French Institute for Textile and Clothing (IFTH) undertook
in 2004 to conduct a survey to update French measurements for the 21st century.
Sizing the French
The IFTH has measured a representative sample of nearly 12,000 men, women,
girls, and boys from all over the country. Participants enter a very sophisticated
booth where they are scanned from head to foot in three dimensions. The IFTH
now has a precise idea of the morphology and body measurements of the French
population according to age, sex, occupation, social status and region. The
results in comparison with European and worldwide data are expected to be
released in 2006. The cost of the operation: 1.2 million euros.
Laser versus hand measures
The last sizing survey dates to the 1970s. The measurements were taken by
hand using a metre bar or a tape measure and lacked accuracy. Today, it takes
10 seconds to examine the morphology of a person under 2.10 m in height and
1.20 m in width.
Anatomical highlighters in the form of reflective markers are placed on key locations such as the wrist, neckline, knee, hip, waist, and shoulder. After a few
manual measures (height, weight, etc.), participants enter the "biometric booth"
in their underwear. Four lasers scan the person from top to bottom. A software
tool extracts 85 measurements for computer analysis. In addition to its accuracy, this technique offers the advantage of providing information on the shape
of certain parts of the body, such as the breasts.
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BIOMETRICS
THE BODY
THE BODY AS IDENTITY
Clothing, kitchen, and health
We already know from this new sizing survey that women are taller today (on
the average 3 to 4 cm) than in 1970 and that 10% of the population is obese.
Textile manufacturers will be able to adjust the size of their clothing as a result.
Other sectors are interested in the results of this survey. This is the case, for
example, of the Bobigny University Hospital that is using the data to determine
relations between morphology and such metabolic disorders as hypertension,
diabetes, and obesity.
Kitchen and car manufacturers will also be making use of these results for such
purposes as adjusting sink height or the distance from a car seat to the pedals.
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BIOMETRICS
THE BODY
THE BODY AS IDENTITY
Is it biometrisable?
Biometrics uses certain physical characteristics that must be both unique to the
person and permanent over time. This is the case for fingerprints, for instance, or
for the iris of the eye. Are there many other biometric identifiers? What makes a
physical characteristic a good biometric element? Have current biometric techniques exhausted all the possibilities?
Face
Teeth
Teeth constitute a record of the organism's life and much precious information
can be gleaned from their state: the damage, the wear, the dental care, and so
on. Unlike biological tissue and bone, teeth are not attacked by insects, bacteria,
immersion, or decay. This is why they are useful in the identification of dead
bodies.
Lips
Lip prints are known in forensics to be as unique to each individual as fingerprints. What's more, lip shapes differ greatly from one person to the next. They
could be used in biometrics once the problem of hygiene is resolved.
Ear
Some scientists maintain that no two ears are alike, even those of identical
twins. Eventually, it would be possible to identify a person on the basis of about
a hundred very precise measurements of the ear. Even though ears develop until
the age of 20 and begin growing again after 45, the proportions remain unchanged, so recognition would be possible at any age.
Facial heat
Faces emit heat and not only when we are blushing. In fact, facial heat patterns
are permanent and unique to the person. With an infrared camera, we can produce a thermal image of the face. This technique, which is still in its experimental phase, may some day be used in airports.
Nose
Noses come in a variety of shapes -upturned, hooked, or straight-but diversity
from one person to the next is not sufficient for noses to qualify as a discriminatory feature. In addition, noses grow and they can be altered by surgery or accident. Noses therefore are not good candidates for biometrics.
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BIOMETRICS
THE BODY
THE BODY AS IDENTITY
Body
Footprints
Footprints, like handprints, are formed at birth and, barring accidents, they
remain unchanged until death. They are unique to the individual and easy to
record. The only difficulty is that you have to take off your shoes to be recognized.
Odour
Every person exudes a distinctive odour. Dogs are perfectly capable of identifying people by their smell. This ability can be put to use by criminal investigators. But can smell be employed as a biometric identifier? A number of questions
would have to be resolved first. Is there any way to ensure that the odour sensor
is capturing the smell of one person only? What happens when an individual
uses perfume? Is body odour really unfalsifiable?
Gait
Because each person has a distinctive way of moving his or her arms, legs, and
hips when walking, gait recognition by camera is possible. But at what age does
a person's gait become stable? And what happens when someone limps or
wears heels? This technique is still in the experimental stage.
Skin
Apparently, the skin of each person absorbs light differently. It would therefore
be possible to identity people by a comparison between the light reflected by
their skin and the light illuminating it. But tanned skin, for example, can alter the
results. This technique is still in its early stages.
Blood
No two people have the same blood. More than 30 markers characterise a person's blood (blood type, A, B, AB or O, Rhesus group + or -, HLA typing, etc.) The
number of possible combinations is so great that, since Man appeared on Earth,
no human being has been exactly like another. So blood could be a good candidate
for biometry but will people be ready to be "bled" for purposes of identification?
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BIOMETRICS
THE BODY
THE BODY AS IDENTITY
Links
Laboratory of Applied Anthropology
http://www.biomedicale.univ-paris5.fr/LAA/ebanque.htm
System of databases in Anthropometry and Ergonomics that features some graphic representations of the human body with the main anatomical reference
points. Each body measurement (length, width, height, depth, perimeter) includes a definition, a description of the method used, and a diagram.
In English
SBH - societe de biometrie humaine
http://biom-hum.com
La Société de Biométrie Humaine, société scientifique de recherche et d'enseignement étudie tous les aspects de la discipline biométrique appliquée à
l'homme. L'étude métrique des êtres humains, leur croissance et l'analyse statistique des résultats sont notamment associées aux recherches sur l'anthropologie, la biométrie du sport, la génétique, la malnutrition, la morphologie, l'obésité, l'orthodontie, la paléoanthropologie, ou les techniques de mesures du
corps humain.
Public intéressé. En français
Campagne Nationale de Mensuration 2003-2004
http://www.ifth.org/mensuration/
En 30 ans, la société française a beaucoup changé : mode de vie, habitudes alimentaires, sédentarisation sont autant d’éléments qui influent sur la morphologie d’une population. Pour établir les nouvelles normes de taille de l’industrie textile une grande action de mesure de la population a eu lieu en 2003-2004 dont
ce site nous révèle toutes les étapes.
Tout public. En français
La Biométrie
http://www.securiteinfo.com/conseils/biometrie.shtml
Découvrez tous les éléments biométrisables chez l'être humain, des caractéristiques physiques telles que l'iris, le visage ou la main aux caractéristiques comportementales comme les frappes au clavier ou la reconnaissance vocale.
Tout public. En français
Le modulor
http://www.ac-poitiers.fr/voir.asp?p=arts_p/b@lise14/pageshtm/page_7.htm
Présentation du Modulor, principe de « mesure harmonique à l’échelle humaine
applicable universellement à l’architecture et à la mécanique » mis au point en
1950 par Le Corbusier, dans lequel le corps humain et ses mesures servent
d’étalon à l’élaboration de l’architecture et des objets du quotidien.
Public intéressé. En français.
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