Regis Petit's Website

Links/Contact

Contents of this page

1. Contact
2. About the Author
   1. Overall
   2. Training
   3. Publications
3. Additional articles
   1. Scientific approach and systemic modeling
   2. Digital optical disk (CD, DVD and BD)
   3. Consumer products and planned obsolescence
   4. Walking robot by Theo Jansen
   5. Hypnotic sculpture by Jennifer Townley
   6. Hypnotic sculpture by Anthony Howe
   7. Wind sculpture by Pierre Luu
   8. Luminous paintings by Bardula
   9. Motion illusions
4. Keyboard shortcuts
5. Site map
6. Design and Accessibility rules
7. Partner schools and organizations
8. Weblinks
   1. Weblinks that deal with Website Design and Checking
   2. Partner directories and websites

1. Contact

To contact the Author thanks to use this email : site@ERROR.com
Warning (anti-spam protocol) : in this email you have to replace the block capital letters by regispetit

2. About the Author

2.1. Overall

Régis Petit, former engineer in Computing at EDF (Electricity of France) is a specialist in Systemic modeling. In 2005, he created this scientific information site which is used by numerous schools and organizations, in particular within the framework of projects at the studies end.
Through his research for nearly twenty years and the rigor of the results obtained, the author is one of the world referents of Billiards physics as well as French referents of hydraulic ram.

The various models made by the author are as follows :

Billards physics : the author wrote in the "Pour la Science" magazine an article fully available on this Website and took part in the broadcasting programmes "Archimède" and C'est pas sorcier - Bille en tête : le billard (Youtube, 25:59). He wrote also the book "Billard - Théorie du jeu" [in English : "Billiards - Theory of the Game"] certified by the Federation of French Billiards.

Hydraulic ram : a thorough study under the three aspects Principle, Theory and Practice. He participates in the activities of the association HSF-Lyon (Hydraulic without Borders - antenna Lyon) for the project "HydroRam" studying the feasibility of an economic hydraulic ram built with commercial components.

Human Nervous System and Learning : a model of baby nervous system in accordance with the learning theory of the psychologist, biologist and epistemologist Jean Piaget.

Relativity : a pedagogical presentation of the basic formulas of Restricted Relativity and General Relativity. This topic also includes a detailed lexicon of terms used in Relativity.

Botany : a catalog of 300 European woody plants associated with an identification method mainly by leaves. This topic also includes a detailed lexicon of terms used in botany.

Music and Language : beyond the well-known aspects of musical sounds (scale, pitch, consonance, timbre, etc.), the author made a pedagogical presentation of some less known aspects of their relationship with human perception (psycho-acoustic) and spoken language. This topic also includes a detailed lexicon of terms used in music, acoustics and spoken language.

Ornithology : a catalog of 300 European birds associated with an identification method mainly by songs and cries.

Meteorology and Navigation : the observation of clouds and winds to predict the weather over 24 hours, completed by basic concepts in air and sea navigation.

Psychology and spirituality : an autobiographical essay "Une approche scientifique du silence" mainly based on the books of Gurdjieff, Arnaud Desjardins and Svami Prajnanpad.

2.2. Training

Régis Petit was born on February 24, 1958.
- Engineer in Mechanics ("Arts et Métiers" - E.N.S.A.M. - Paris)
- Engineer in Applied Mathematics (E.N.S.E.E.I.H.T. - Toulouse)
- P.H.D. in Computing, Artificial Intelligence and Robotics (I.N.P.T. - Toulouse)
- Independent researcher in systemic modeling. France.

2.3. Publications

1. Livre "Billard - Théorie du jeu", Chiron, 1997, 2004 (ISBN 978-2-7027-0999-3).
2. Livre "Bélier Hydraulique - Une machine insolite", autoédition, janvier 2008 (ISBN 978-2-9521300-1-1), completely integrated into the Internet topic "Hydraulic ram".
3. Article "La pratique du billard", Pour La Science N°246, Avril 1998.
4. Internet topic "Physics of Billards", 2005 (CopyrightFrance.com).
5. Internet topic "Hydraulic ram", 2007 (CopyrightFrance.com).
6. Internet topic "Human Nervous System and Learning", 2009 (CopyrightFrance.com).
7. Internet topic "Relativity", 2017 (CopyrightFrance.com).
8. Internet topic "Botany", 2019 (CopyrightFrance.com).
9. Internet topic "Music and Language", 2020 (CopyrightFrance.com).
10. Internet topic "Ornithology", 2020 (CopyrightFrance.com).
11. Internet topic "Meteorology and Navigation", 2021 (CopyrightFrance.com).
12. Livre "Une approche scientifique du silence", autoédition, janvier 2004 (ISBN 2-9521300-0-0).
13. Other articles : see below.

3. Additional articles

3.1. Scientific approach and systemic modeling

The scientific approach consists mainly of six steps :
    1. Observation and measurement of a phenomenon ;
    2. Systemic modeling and formulation of the simplest theory correctly accounting for all the observed facts ;
    3. Experimentation and validation of the theory ;
    4. Comparison with existing theories ;
    5. Communication of the results obtained to his peers for revalidations and possible criticisms ;
    6. Use of the theory to predict or reproduce the phenomenon.
Warning : Any criticism must be constructive to be admissible, that is to say be factual, without value judgment and without ironic or disrespectful remarks, in short, be worthy of the critic.

The systemic modeling is a stage of the scientific approach which consists in describing physical phenomena in the form of systems. The challenge is to find the right level of model : neither too simple to take into account all the physical observations, nor too complex to set the model parameters from these observations.
Systemic modeling also aims to divide systems into subsystems in an optimal way according to four main principles of systemes urban planning :

1. "Divide to conquer" or modularity principle. The goal is to cut the system into subsystems of optimal size and each having its autonomy of exploitation and use.
The temporary unavailability of a subsystem does not prevent the other subsystems from operating.

2. "Group to simplify" or subsidiarity principle. The goal is to pool what can be pooled and to treat each specificity as a differential with respect to the general case.
Complexity is isolated in easily manageable special case subsystems and does not put generic subsystems at risk.

3. "Distribute to better communicate" or reducing adhesions principle. The goal is to minimize the adhesions between subsystems and to compensate by a dynamic cooperation between them.
The data exchanged between subsystems are only created and modified in a single subsystem (notion of proprietary subsystem).
The information exchanges between subsystems are done via standardized interfaces.

4. "Start small but think big" or progressiveness principle. The goal is to provide for an evolution of the system in stages and starting from the existing one.

3.2. Digital optical disk (CD, DVD and BD)

Definition :
The Digital Optical Disk (DON) is a removable flat disk used to store digital data in the fields of computers, audio and video.
The best known disks are CD, DVD and BD :

• CD (Compact Disk) is used to store all types of digital data with reduced storage capacity (approximately 700 MB). Its reading system is an infrared laser whose wavelength is 780 nm, which does not allow reading DVD and BD.
• DVD (Digital Versatile Disk) can also store any type of digital data with a large storage capacity (4.7 GB on average). Its reading system is a shorter wave infrared laser (650 nm). The often-used term "Digital Video Disk" is a misnomer because the stored data may also be non-video.
• BD (Blu-ray Disk) can store high-definition video data (from 7 GB to 128 GB). Its reading system is a blue-violet laser with an even shorter wave (405 nm), which makes it possible to read video DVD and audio CD.

• Base layer in transparent plastic material (polycarbonate) ;
• Organic dye layer (only for ±R disks) ;
• Reflective metallic layer which reflects the laser beam towards the photosensor of the laser head ;
• Protective layer (anti-UV varnish) which protects the reflective layer ;
• Polymer layer supporting the printed information.

• Quality : choose a major brand disk rather than a generic disk.
• Origin : avoid buying at train stations or markets or fairs, as disks as discs can stay in damp or direct sunlight for days on end. Beware of batches of 50 or 100 DVD which are sold without a protective case.
• Wear by mechanical contact : no possible wear because the reading head is never in contact with the disk.
• Aging or corrosion : prefer ±R disks over others. The main factor that determines the lifetime of a disk is indeed the reflective layer which is generally gold or silver for ±R disks and aluminum for the others (therefore more fragile to corrosion).

• Handling : take the disk by placing one finger in the center and another on the edge. Do not touch the engraved part below and above (the fingers sweat being acidic). Do not put the disk anywhere. If the protective layer is scratched, the cracks allow air to pass through which oxidizes the reflective layer.
• Storage : place the disk upright in its case, the printed side upwards.
• Cleaning : use a dry soft cloth, wiping the disk from the center of the disk outwards and never in a circle.
• Burning : do not use an aging burner. Ensure that the disk is compatible with the burner. Burn at low speed (4x or 8x) neither too slow (1x) nor too fast (52x).

• Labeling : label only on the internal transparent band.
• Storage : store the disk preferably in a dry place, in the dark and at a constant temperature (between 4°C and 25°C). Keep the disk in its original sleeve or case, and in an upright position to avoid warping.
• Backup : make a copy every 5 years.

3.3. Consumer products and planned obsolescence

Current or durable consumer products offered on the markets do not always have the expected quality. The main causes are the following :

1. "Construction" defect of the product
Three types of fault exist :

• Design defect : the defect is often irremediable.
• Correct but flanged design : the consumer is not always aware of this. Example : a large number of motion detectors with PIR (Passive InfraRed) technology have chaotic operation when placed outdoors in the presence of wind, rain or humidity, outside the limits of the robustness of the electronic card or the operating ranges of the detection algorithm.
• Produce defect : the test campaigns before leaving the factory are not always sufficient and a large number of products on the market are defective on their first use.

• Product whose functioning is degraded after a certain use period (example : women's tights which generally do not last more than six uses, whereas historically nylon stockings were extremely robust and resistant) ;
• Product whose operation is blocked after a certain use period (example : some printers equipped with a smart chip, forcing the ink cartridges to be replaced before they are empty) ;
• Product of which one of the hardware components is weakened from the design stage (example : screen or computer battery) ;
• Product whose defective parts are almost inaccessible (example : bearings of front-loading washing machines) or cannot be removed (example : some smartphones and laptops whose battery or screen is fixed with industrial glue or screws not standard) ;
• Product whose spare parts or accessories are non-existent in the manufacturers' catalog (example : LED and transformer integrated in the luminaires) or taken out of the catalog (example : old coffee maker bowl) or incompatible with the product (examples : new battery, new consumable) ;
• Product whose maintenance or repair is expensive compared to the residual value of the product or the purchase price of a new product (economic obsolescence);
  
• Product whose software support is discontinued and does not allow updating or downloading applications (software obsolescence) ;
• Operational product but become outdated in the eyes of consumers (cultural or aesthetic or psychological obsolescence).

3.4. Walking robot by Theo Jansen

Theo Jansen is a Dutch sculptor who in 1991 created strange creatures including the walking robot (see Figures 1 and 2 above).

Working :
This walking robot is a mechanism with very light legs which can move on a horizontal plane under the wind action or on an inclined plane under the action of its own weight (see video cf [Jansen, Plaudens Vela]).
The only actuator in the robot is a central crankshaft making the connection between the legs and the robot body (see red while on Figure 2, and also [Exergia]).
For a robot with three pairs of legs, the crankshaft has three cranks offset successively by 120° to have a constant movement of the robot during the propulsion phase (see Figure 2).

Body description :
The robot body consists of a horizontal platform (length 2a) and vertical fixed supports (length l) carrying the crankshaft (eccentricity m). See Figure 3 above.
The double length (a) of the platform is calculated to ensure non-collision between the front legs and the rear legs.
The length (l) of the supports can be modified to ensure an overall horizontal movement of the robot. Increasing or decreasing the length (l) amounts to pivoting all the bars of each leg around each fixed point F.

Legs description :
Each leg consists of ten articulated bars (bars b to k) of which two form a rigid link (bars e and h)). See Figure 3 above.
The two legs of the same pair are identical and mirror each other on each side of the crankshaft.
The foot of each leg describes an ovoid curve whose lower part is almost flat and horizontal, thus allowing the foot to be in contact with the ground during the propulsive phase.
In the return phase, the foot lifts off the ground and the robot can step over small obstacles without lifting its body too much.
The table of Figure 3 gives the length of each bar according to different authors :

• Jansen (cf [Wikipedia, Jansen mechanism]) ;
• Jansen by multiplying by the scale factor 15/38 ;
• Giesbrecht according to its optimized method for which the bars are calculated by minimizing the quantity of energy used per unit of distance traveled (cf [Giesbrecht, Design and optimisation]).

3.5. Hypnotic sculpture by Jennifer Townley

Jennifer Townley is a Dutch artist who has created hypnotic mobile sculptures including "Asinas" in 2015 (see Figure 1 above, and video "Asinas" in [Art Juice]).
When viewed at a standstill from the front, it looks like a double helix like the usual representation of DNA.

Description (cf [Jennifer Townley]) :
"Asinas" is a mobile sculpture composed of two helixes that intertwine and slide into each other, producing a fluid and natural movement.
The sixty-five white wooden bricks that form the two helixes increase in size towards the middle of the sculpture, giving it a conical shape.
Each brick has the shape of a Z with 90 degree angles. The bricks of a helix are fixed on the rotation axis. The bricks of the other helix are connected to one another through small spacers (see Figure 2 above from [Amogh Jadhav]).
The two helixes slowly rotate in opposite directions and at slightly different speeds, gradually transforming the sculpture.

A demonstration of how this sculpture works helps to better understand this description (see video "Asinas Working Demonstration" in [Amogh Jadhav] and video "SolidWorks Mechanical Sculpture" in [tecnoloxia.org]).

Materials (cf [The Plus Paper]) :
The white bricks are made from painted wood. The frame is made of steel as well as all the parts connecting the gears to their axes, the bearings to the frame, etc.
Then there are all the other parts : an electric motor, heavy steel spur gears and sprockets, two belts and lots of bearings.

Sources :
Art Juice - Les sculptures mobiles et hypnotiques de Jennifer Townley.
L'Usine Nouvelle - Hypnotiques, ces sculptures cinétiques vous étonneront.
Jennifer Townley - Asinas.
Asinas - Jennifer Townley - 2015 - Kinetic art (Youtube 2:31).
Amogh Jadhav - Asinas.
Amogh Jadhav - Asinas Working Demonstration (Youtube 2:14).
tecnoloxia.org - As esculturas cinéticas de Jennifer Townley.
MadCadSkills : Jennifer Townley - SolidWorks Mechanical Sculpture (Youtube 3:43).
The Plus Paper - Asinas : Fluent Movement.

3.6. Hypnotic sculpture by Anthony Howe

Anthony Howe is an American sculptor who has created hypnotic mobile sculptures including "Di-Octo" in 2014 (see Figures 1, 2 and 3 above, and "Di-Octo" video in [Anthony Howe] and [KULTT]).
Di-Octo is a half-octopus, half-star, wind-driven and near-silent mobile sculpture.
The original Di-Octo, designed and made by Anthony Howe, has been industrialized in two identical copies by Show Canada Inc (Laval steelworks in Quebec) as follows (cf email of March 10, 2023 from David Boulay (Show Canada Inc) to Régis Petit) :

• Di-Octo II or Fern Pull I or Shidahiku or Shindahiku : first unit manufactured by Show Canada and installed in 2017 in Montreal (Canada), Sir George Williams campus of Concordia University, in front of the University's Pavillon Henry-F.-Hall, on boulevard De Maisonneuve at the corner of rue Mackay (cf [Anthony Howe, https://www. howeart.net/news][The DC Blike Blogger]).
  
• Di-Octo II or Fern Pull II : second unit manufactured by Show Canada and installed in 2018 in Washington DC (USA), on New Jersey Avenue, near Nationals Park in the Navy Yard district of southeast DC (cf [The DC Blike Blogger]).
  

• Octo or Octo II : version with 32 arms each carrying 10 domes, with drive finger type inter-arm connections, installed in 2013 in Greenville (cf [reddit]), State of South Carolina (USA), at the corner of the McBee Avenue and Falls Street.
• Octo I : version with 32 arms each carrying 10 domes, with drive finger type inter-arm connections, installed in 2016 in Dubai (cf [What's on][UAE]) at The Beach, the beach of "Jumeirah Beach Residence" (JBR).
• Octo III : horizontal ring version, with 32 arms each carrying 10 domes, with double cardan type inter-arm connections, installed in 2016 in Dubai (cf [What's on][UAE]) at the City Walk Mall on Al Safa St., in front of "Paul and Argo Tea Café".

3.7. Wind sculpture by Pierre Luu

Pierre Luu is a French sculptor who has created sculptures with unpredictable movements, driven by wind or water, including the "wind turbine with random motion" (see Figures above, and video "Mobile eolien art cinétique" in [Pierre Luu]).

Description :
Figure 1 above : general view (cf [Art et Eau]).
Figure 2 above : zoom on blades twist angle (video clip 0:12).
Figure 3 above : zoom on blades lenght (video clip 0:22).
The "wind turbine with random motion" is made up of 5 moving parts in unstable equilibrium (cf [Pierre Luu - Quelque chose ne tourne pas rond][Art et Eau - Quelque chose ne tourne pas rond]).
The balance is all the more unstable as there is no weather vane to orient the sculpture in the wind direction. The blue ball is aesthetic and symbolizes the Earth (cf my email of March 5, 2023 from Pierre Luu to Régis Petit).
The two blades are of different size with a secondary rotation nested within the primary rotation (cf [Pierre Luu - Eolide].
The mobile elements are fixed by ball bearings for all sculptures in project version (cf email of March 7, 2023 from Pierre Luu to Régis Petit). This combination allows fluid rotations and movements even in light winds (cf [Pierre Luu - Fragments mobile éolien).
The sculpture slowly comes to life and changes shape thanks to the wind action. The movement is maintained by inertia due to the balance of the masses (cf [Art et Eau - Quelque chose ne tourne pas rond]).
The sculpture unfolds in an enigmatic choreography and only finds temporary stability when the blades reach a certain speed (cf [Pierre Luu - Quelque chose ne tourne pas rond]).
The whole is designed in a search for balance between the masses, the gravity centers, the surfaces exposed to the wind and the relative angles of the surfaces (cf [Pierre Luu - Quelque chose ne tourne pas rond]).
Material : stainless steel and composite materials (cf [Art et Eau - Quelque chose ne tourne pas rond]).
Height : 3 m 50 (cf [Art et Eau - Quelque chose ne tourne pas rond]).

Sources :
Pierre Luu - Mobile eolien art cinétique (YouTube, 01:57).
Pierre Luu - Un art en mouvement - Sculptures éoliennes et mobiles.
Pierre Luu - Un art en mouvement - Quelque chose ne tourne pas rond.
Pierre Luu - Un art en mouvement - Fragments mobile éolien.
Pierre Luu - Un art en mouvement - Eolide.
Pierre Luu - Un art en mouvement - Solaris : sculpture éolienne et solaire autonome en énergie.
Art et Eau - Ellipse, quelque chose ne tourne pas rond.

3.8. Luminous paintings by Bardula

Bardula is a pseudonym created by a Belgian artist who currently lives and works in France.
Bardula creates luminous paintings including the hypnotic paintings "Blue Interferences" and "Blue ice" (see Figures 1 and 2 above).

Sources :
Light ZOOM Lumière.
Bardula.

3.9. Motion illusions

       

       

Here is a selection of the best motion illusions (see above Figure 1 cf [GomboDigital], Figures 2 to 5 cf [Sélection.ca] and Figure 6 cf [Akiyoshi Kitaoka]) :
1. Rotating vortex (Vectordivider image via Getty Images)
2. Rotating spirals (Vectordivider image via Getty Images)
3. Mesmerizing effect (Mark Grenier image via Shutterstock)
4. Scroll (Guten Tag Vector image via Shutterstock)
5. Glitter Grid (Mark image via Shutterstock)
6. "Expanding pupils" (Image from Akiyoshi Kitaoka)

Sources :
Sélection du Reader's Digest (Canada) - 24 illusions d'optique complètement étourdissantes.
GomboDigital - 5 illusions d'optique qui vont vous scotcher/.
Akiyoshi Kitaoka - Anomalous motion illusions 35.

4. Keyboard shortcuts

The following Access keys (figures from 0 to 9) can be used on this Website :

• 0 Help (and Links/Contact)
• 1 Home
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• 3 Music
• 4 Ornithology
• 5 Billiards
• 6 Hydraulic ram
• 7 HNS (Human Nervous System)
• 8 Relativity
• 9 Botany
• Search form control (only on the Home page)

These Access keys can be used via a combination of keyboard shortcuts. The list of these combinations sorted by Operating System then by Browser is as follows.
Warning : Shift is sometimes useless on some keyboards (including the QWERTY and QWERTZ keyboards).

• Windows :
  • Internet Explorer : Alt + Shift + Access key then Enter
  • Chrome / Mozilla / Firefox / Netscape / K-Meleon / Opera 15+ / Safari 1.2+ : Alt + Shift + Access key
  • Opera 7+ : Esc + Shift + Access key
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5. Site map

This Web site contains 63 html pages.
The pages translated in English are preceded by a star.

1. * Accueil  (Home)
2. * Billard  (Billiards)
   1. * Théorie du jeu  (Theory of the Game)
   2. * La pratique du billard  (The Art of Billiards Play)
   3. * Bibliographie  (Bibliography)
   4. C'est du billard, reportage ARTE
3. * Bélier hydraulique  (Hydraulic ram)
   1. Pages de Hervé de Baillenx
   2. Principe de fonctionnement
   3. Théorie
   4. Pratique
   5. Annexe
   6. Notations
   7. Glossaire
   8. * Bibliographie  (Bibliography)
   9. * Sommaire général  (Overall Table of contents)
4. * Système Nerveux Humain  (Human Nervous System)
   1. Introduction
   2. Piaget
   3. Description fonctionnelle
   4. Glossaire
   5. * Bibliographie  (Bibliography)
   6. * Sommaire général  (Overall Table of contents)
5. * Relativité  (Relativity)
6. Botanique
   1. Liste des plantes ligneuses dont le nom commun commence par la lettre A
   2. Liste des plantes ligneuses dont le nom commun commence par la lettre B
   3. Liste des plantes ligneuses dont le nom commun commence par la lettre C
   4. Liste des plantes ligneuses dont le nom commun commence par la lettre D, E ou F
   5. Liste des plantes ligneuses dont le nom commun commence par la lettre G
   6. Liste des plantes ligneuses dont le nom commun commence par la lettre H, I, J, K ou L
   7. Liste des plantes ligneuses dont le nom commun commence par la lettre M, N ou O
   8. Liste des plantes ligneuses dont le nom commun commence par la lettre P
   9. Liste des plantes ligneuses dont le nom commun commence par la lettre Q, R ou S
   10. Liste des plantes ligneuses dont le nom commun commence par la lettre T, U, V, W, X, Y ou Z
7. Musique
8. Ornithologie
   1. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre A
   2. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre B
   3. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre C
   4. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre D, E ou F
   5. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre G
   6. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre H, I, J, K ou L
   7. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre M, N ou O
   8. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre P
   9. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre Q, R ou S
   10. Catalogue des oiseaux d'Europe dont le nom commun commence par la lettre T, U, V, W, X, Y ou Z
9. Météorologie
10. * Liens/Contact  (Links/Contact)
11. * (Warning)

6. Design and Accessibility rules

At the time of last update of this page (see bottom of this page), all Web pages of this site have the following properties :
- they comply with W3C normes (HTML and CSS) ;
- they comply with Web Content Accessibility Guidelines (WCAG) 2.0 with Level AA conformance.

Design and Accessibility rules of this site :

1. Web design
   1. Structuration du site en pages : selon une arborescence hiérarchique limitée à une profondeur de trois (règle des "trois clics").
   2. Version bilingue : version français/anglais de (presque) chaque page.
   3. Homogénéité des pages : même présentation et mêmes couleurs.
   4. Liens entre pages du site : depuis chaque page, accès a minima aux pages "Accueil", "Liens/Contact", ainsi qu'aux pages de type père, oncles, frères et fils.
   5. Page d'accueil : présentation simple, sur un seul écran, avec moteur de recherche interne.
2. Web ergonomy (presentation and browsing)
   1. Page : présentation structurée verticalement selon Barre de menu puis Contenu puis Pied de page, et tenant horizontalement dans l'écran.
   2. Barre de menu : avec bouton "English/Français" de type bascule.
   3. Contenu d'une page : structuration linéaire selon titre (rappel de la page père), chapitre (nom de la page courante), sommaire local (uniquement si page longue), paragraphe, sous-paragraphe, sous-sous-paragraphe...
   4. Pied de page : avec mention du copyright, année de création, nom de l'auteur et date de dernière mise à jour de la page.
   5. Liens : (presque) tous commençant par une lettre majuscule, et de couleur différente selon le type de lien (non visité, visité, survolé, activé).
   6. Liens vers fichier téléchargeable : avec indication du type de fichier (.gif, .jpeg...) et de sa taille (en Ko ou Mo).
   7. Liens extra-page : avec texte court, explicite quant à la page destination.
   8. Liens intra-page : uniquement dans les pages longues.
   9. Liens "Précédent/Suivant" : uniquement entre chapitres, entre paragraphes et entre sous-paragraphes.
   10. Images porteuses d'information : avec texte alternatif (attribut "alt"), court et explicite quant à la fonction et à l'aspect.
   11. Plan de page : existe.
   12. Paragraphes : justifiés (à gauche et à droite) et indentés en première ligne.
   13. Typographie : aucun soulignement, ni texte en majuscule, et avec style "italique" uniquement dans des cas précis.
3. Accessibility to sensory handicapped
   1. Changements de langue : indiqué systématiquement (attribut "lang" dans chaque objet de type tableau, liste, bloc (balise "span"), etc.).
   2. Objets multimédias (animation, vidéo, son) : ni clignotement, défilement ou mise à jour automatique d'information, ni image animée ou à zone réactive cliquable, ni fenêtre pop-up, ni son, ni listes déroulantes, ni boîtes de dialogue. Les boutons de désactivation des animations et du son sont en effet impossibles à trouver rapidement par un non-voyant.
   3. Couleurs (utilisation) : rien ne repose uniquement sur la couleur (indication d'une action, sollicitation d'une réponse, distinction d'un élément visuel).
   4. Couleurs (standardisation) : prises parmi les 16 couleurs de base du standard HTML 4.01 (voir tableau ci-dessous, avec Nom HTML, Nom français et Code hexadécimal selon la notation #RRVVBB).
   5. Couleurs (contraste) : contraste particulièrement adapté aux daltoniens déficients en vert (soit 80 % des daltoniens, ces derniers représentant 8 % des hommes et 0,5 % des femmes), selon les règles suivantes (voir tableau ci-dessous) :
         - Arrière-plan : sans motifs ni texte (donc fond uni) ; couleur "white" pour le fond de page ; couleurs "aqua", "silver" et "white" pour les fonds de menu ; couleurs "yelow" et "red" pour les fonds de lien (respectivement survolé et activé) situés en arrière-plan par rapport au texte de lien.
         - Premier plan : couleur "black" pour le texte de page ; couleur "blue" et "purple" pour les textes de lien (respectivement non visité et visité) ; couleur "yellow" et "red" pour les fonds de lien situés en premier plan par rapport au fond de page ou de menu.
   6. Police de caractères : sans empattements, ni embellissements, ni enluminures (police sans sérif).
   7. Images : suivies si nécessaire d'un équivalent textuel expliquant le contenu de l'image.
   8. Titres : balises "h1", "h2", "h3"... logiquement enchaînées et en cohérence avec la présentation des pages en titre, chapitre, paragraphe...
   9. Tableaux : avec résumé indiquant la fonction menu/données et le nombre de colonnes (attribut "summary"), avec en-têtes de colonnes (attribut "th"), avec si nécessaire correspondance entre cellule et colonne (attributs "id" et "headers").
   10. Listes : avec numérotation systématique.
   11. Formules mathématiques : écriture littérale, y compris les fonctions mathématiques (exemple : sin[x]).
   12. Raccourcis clavier : chiffres de 0 à 9 (dont les touches couramment utilisées : 0 Aide ; 1 Accueil).

   The following table gives the contrast between each foreground color (in lines) and each background color (in rows) for the 16 basic color from HTML 4.01
   This website uses only 24 contrasts indicated by the text "OUI", especially suited to green colorblind deficient.

   Nom HTML

   black

   navy

   blue

   green

   teal

   lime

   AQUA

   maroon

   purple

   olive

   GRAY

   SILVER

   RED

   fuchsia

   YELLOW

   WHITE

   Nom français

   noir

   bleu foncé

   bleu

   vert

   bleu vert

   vert brillant

   cyan

   marron

   violet

   vert olive

   gris foncé

   gris clair

   rouge

   rose

   jaune

   blanc

   Code hexa

   000000

   000080

   0000FF

   008000

   008080

   00FF00

   00FFFF

   800000

   800080

   808000

   808080

   C0C0C0

   FF0000

   FF00FF

   FFFF00

   FFFFFF

   BLACK

   non

   non

   non

   non

   non

   non

   OUI01

   non

   non

   non

   OUI02

   OUI03

   non

   non

   non

   OUI04

   navy

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   BLUE

   non

   non

   non

   non

   non

   non

   OUI05

   non

   non

   non

   OUI06

   OUI07

   OUI08

   non

   OUI09

   OUI10

   green

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   teal

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   lime

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   aqua

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   maroon

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   PURPLE

   non

   non

   non

   non

   non

   non

   OUI11

   non

   non

   non

   OUI12

   OUI13

   OUI14

   non

   OUI15

   OUI16

   olive

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   gray

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   silver

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   RED

   non

   non

   non

   non

   non

   non

   OUI17

   non

   non

   non

   OUI18

   OUI19

   non

   non

   non

   OUI20

   fuchsia

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   YELLOW

   non

   non

   non

   non

   non

   non

   OUI21

   non

   non

   non

   OUI22

   OUI23

   non

   non

   non

   OUI24

   white

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   non

   
   
4. Html code
   1. Balises "!DOCTYPE", "html" et "head" : efficaces et en nombre restreint (pour les moteurs de recherche type Google).
   2. Feuille de style (.css, 3 Ko) : feuille externe unique avec attributs de taille redéfinis en relatif ("em" ou pourcentages) plutôt qu'en absolu (pixels).
   3. Balise "body" : avec attribut "bgcolor" en doublon de la feuille de style (pour compatibilité avec versions de code html inférieures à 3.2).
   4. Cadres (ou "frame") : aucun.
   5. Fenêtres secondaires : aucune.
   6. Liens javascript : aucun (hormis éventuel cassage du nom de domaine).
   7. Paragraphes : tous explicites (avec balise "p") afin de pouvoir jouer dessus avec la feuille de style.
   8. Mathematical symbols : coded in html when the code exists (examples : ≤ ∞ Δ ◊).
   9. Fichiers : nommage représentatif des deux premiers niveaux de la structure du site, sans blanc, ni caractère accentué (car problème sur serveurs Unix). Majuscules évitées au maximum.
   10. Temps d'accès aux pages : très court, avec quelques pages "pesant" au plus 100 Ko.

7. Partner schools and organizations

The following schools or organizations used this website :
Caption :
CPGE : Classes Préparatoires aux Grandes Ecoles
PFE : Projet de Fin d'Etude
TIPE : Travaux d'Initiative Personnelle Encadrée
TPE : Travaux Pratiques Encadrés

About the topic "Physics of Billiards" :

1. Bourg-en-Bresse, Lycée Lalande, TIPE : Le billard, Mickaël Jacques, CPGE 2ème année, PC, 2012.
2. Caen, Lycée Victor Hugo, TIPE : Le billard, Wilfried Lerot, CPGE 2ème année, PSI, 2008.
3. Dijon, Lycée Carnot, TIPE : Le bowling, Pierre Goguelat, CPGE 2ème année, MP, 2011.
4. La Flèche, Lycée Prytanée, TIPE : La physique du billard, Matthieu Dolliou, CPGE 2ème année, MP*, 2014.
5. Lille, Lycée Faidherbe, TIPE : Le billard, Vincent Bolle, CPGE 1ère année, MPSI, 2008.
6. Lille, Lycée Faidherbe, TIPE : Le billard, Sylvain Capelle, CPGE 2ème année, PC, 2011.
7. Lille, Lycée Faidherbe, TIPE : Le billard, Maxime Duprez et Romain George, CPGE 2ème année, PSI, 2014.
8. Lyon, ECAM, TIPE : Le billard, Jérémy Crétin et Jérémy Quentin, CPGE 2ème année intégrée, PT, 2012.
9. Lyon, Lycée Aux Lazaristes, TIPE : Le billard, Florian Carra, CPGE 2ème année, MP, 2011.
10. Nancy, Lycée Henri-Poincaré, TIPE : La physique du billard, Julien Vukasin, CPGE 2ème année, MP, 2011.
11. Neuilly-sur-Seine, Lycée Pasteur, TIPE : La physique du billard, Swann Bareilhe, CPGE 2ème année, MP, 2012.
12. Nice, Lycée Masséna, TIPE : Le billard, Siméon Nenoff, Frédéric Bieber et Adrien Génin, CPGE 2ème année, MP et PC, 2008.
13. Paris, Lycée Saint-Louis, TIPE : La dynamique du billard, Laura Sobra, CPGE 2ème année, PC, 2011.
14. Perpignan, Lycée Arago, TIPE : Le billard, Baudoin Espieux, CPGE 2ème année, PSI, 2013.
15. Reims, Lycée Roosevelt, TIPE : Le billard, Chloé Deflandre, Ellyn Dubecq, CPGE 1ère année, MPSI, 2016.
16. Saint-Etienne, Lycée Fauriel, TIPE : La mécanique du billard, Victor Soriano, CPGE 2ème année, MP, 2011.
17. Valbonne, Lycée International, TIPE : Le billard, Caroline Boyer, CPGE 2ème année, MP, 2012.

About the topic "Hydraulic ram" :

1. Besançon, Lycée Victor Hugo, TIPE : Le bélier hydraulique, Anthony Doubey, CPGE 2ème année, PSI, 2015.
2. Brest, ENSTA ParisTech, Projet de pompe hydraulique autonome basé sur un multiplicateur de pression, Vincent Macaigne, 2014.
3. Burundi, Faculté des sciences appliquées, Département de Génie Electromécanique, PFE : Possibilité technique et énergétique du pompage pour l'irrigation d'une région agricole du Nord du Burundi, Claude Nkonji, 2009.
4. Clermont-Ferrand, Lycée Blaise Pascal, TIPE : Le bélier hydraulique, Baptiste Durand, CPGE 2ème année, PSI, 2014.
5. Cluny, Lycée La Prat's, TIPE : Le bélier hydraulique, Geoffroy de Saint-André, CPGE 2ème année, PT, 2011.
6. Grenoble, INP-ENSE3, Maquette transparente de bélier hydraulique (YouTube, 03:19) ; Bélier hydraulique : Maquette transparente (YouTube, 06:43) Cyril Benistand, Matthieu Villevieille, Robin Vallée, Thomas Fayer, Pierre Coutouly et Alexandre Wettstein, Atelier d'ingénierie, 2015.
7. Grenoble, INP-ENSE3, Modélisation de bélier hydraulique, Jean-Côme Biscay, Kenza Taoussi, Erwan Tardy, Raphaël D'Oliveira, Laurent Dumas, El Bachir Chakir et Pierre Boucher, Atelier d'ingénierie, 2015.
8. Grenoble, INP-ENSE3, Projet de bélier hydraulique en haute montagne ; Alex Croutz et Jérémie Serfass, 2ème année, Filière Hydraulique, Ouvrages et Environnement, Option Génie Hydraulique et Ouvrages, 2016.
9. Longwy, IUT Longwy, Université Henri Poincaré Nancy1, Projet tutoré : le bélier hydraulique, Quentin Ducassou, Julien Breemersch, Clément Malliard, 2ème année, GTE, 2009.
10. Lyon, ECAM, TIPE : Le bélier hydraulique, Johanna Ankri, Justine Abou Chacra, CPGE 2ème année intégrée, PT, 2015.
11. Lyon, INSA, PFE : HydroRam (.pptx, 2.5 Mo), Quentin Letellier, 2012.
12. Lyon, Lycée du Parc, TIPE : Du coup de bélier dévastateur au bélier hydraulique salvateur, Florent Joyet, CPGE 1ère et 2ème années, MPSI et PSI, 2007 & 2008.
13. Lyon, Lycée La Martinière-Monplaisir, TIPE : Le bélier hydraulique, Tristan Jardel et Ilham Hamdame, CPGE 1ère année, MPSI, 2008.
14. Margency, Lycée Notre-Dame de Bury, TPE : Le bélier hydraulique, Nadir Bouchene, Marie Magana, Victor Gillibert, 1ère S, 2010.
15. Montpellier, Ecole d'ingénieur SupAgro, Institut des Régions Chaudes, Le bélier hydraulique : mémoire de fin d'études d'ingénieur en agronomie tropicale spécialisé en gestion sociale de l'eau, Adrien Busson, 2010.
16. Nantes, Lycée Clémenceau, TIPE : Le bélier hydraulique, David Rousseleau, Jonathan Coueraud et Jules Douet, CPGE 1ère année, MPSI, 2008.
17. Nantes, Lycée Eugène Livet, TIPE : Le bélier hydraulique, Romain Leluc et Gwenhael Darcy, CPGE 1ère et 2ème années, PTSI et PT, 2008 & 2009.
18. Nice, Lycée Masséna, TIPE : Le bélier hydraulique, Martin Roux, CPGE 2ème année, PC, 2019.
19. Nogent-sur-Oise, Lycée Marie-Curie, Projet : Le bélier hydraulique, Louison Richet, Terminale STI2D, 2013.
20. Paris, AgroParisTech, PFE : Le bélier hydraulique (projet de valorisation patrimoniale sur le canal de Gignac), Pauline Poutrain, Maelle Delabre, Félicie Aulanier, Christophe Abraham, Paul-Emile Noirot-Cosson, 3ème année, Ingénierie de l'Environnement, 2012.
21. Paris, Institut de France, Panneaux descriptifs du fonctionnement d'un bélier hydraulique, dans le cadre du Printemps de l'Industrie (Pavillon de Manse, mars 2009) et des Journées de la Rose (Abbaye royale de Chaalis et musée Jacquemart-André - Chaalis, juin 2009), J.M. Vasseur, Service culturel et pédagogique.
22. Paris, Lycée Claude Bernard, TIPE : Principe du bélier hydraulique, Baptiste Mathae, CPGE 2ème année, PSI, 2015 : Le bélier en action (.jpg, 100 Ko), Constitution (.jpg, 100 Ko).
23. Paris, Lycée Saint-Louis, TIPE : Le bélier hydraulique, Mickael Roucou, CPGE 2ème année, PSI, 2011.
24. Paris, Lycée Stanislas, TIPE : Le bélier hydraulique, Matthieu Ansart, CPGE 2ème année, PC, 2015.
25. Pau, Université de Pau et des Pays de l'Adour, Projet : Etude et Conception d'un bélier hydraulique, David Béritault et Luc Champault, Master Ingénierie des Systèmes Industriels (ISI), 2007.
26. Rouen, Lycée Corneille, TIPE : Le bélier hydraulique, L. Duflot, CPGE 2ème année, PSI, 2011.
27. Tananarive (Madagascar), Université d'Antananarivo, ESPA, Contribution à l'étude et réalisation d'un bélier hydraulique : mémoire de fin d'étude d'ingénieur grade Master 2 en Génie Mécanique et Industriel (.pdf, 2.6 Mo), Jean Harson Rakotonoely, 2019.
    A noter que ce mémoire reprend quasi-intégralement le texte et les équations des pages Web du Sujet Internet "Bélier hydraulique", comme suit :
    - Chapitre Principe : recopie intégrale des Phases de fonctionnement (sans mention de la source) : pages 10 à 11 du mémoire.
    - Chapitre Théorie : recopie quasi-intégrale de tout le chapitre (sans mention de la source) : pages 12 à 38 du mémoire.
    - Chapitre Pratique : recopie adaptée des paragraphes "Calcul d'un bélier" et "Bélier prototype à construire soi-même" : pages 42 à 47, et 54 à 55 du mémoire.
28. Toulouse, Lycée Déodat de Séverac, TIPE : Le bélier hydraulique, Pauline Vie, Marc Chauchat, Gautier Combelles, CPGE 2ème année, PSI, 2015.
29. Valbonne, Lycée International, TIPE : Le bélier hydraulique, Raphael Chattot, CPGE 2ème année, PSI, 2011.
30. Valbonne, Lycée International, TIPE : Le bélier hydraulique, Samuel Franch, CPGE 2ème année, PC, 2021.

About the topic "Ornithology" :

1. Vanves, Editions du Chêne, Les chants des oiseaux, Projet de planche pour le livre "Les Miscellanées des sciences naturelles", Editions du Chêne 2023, Suzanne Labourie, Equipe éditoriale.

8. Weblinks

8.1. Weblinks that deal with Website Design and Checking

8.2. Partner directories and websites

el annuaire
Ce site est listé dans la catégorie Sciences et technologie

Copyright © 2005 Régis Petit.               Last page update : March 20, 2023.