Showing posts with label system. Show all posts
Showing posts with label system. Show all posts
Art Lessons from Humans (Painting)
Mrs. Ibreck (Lady Eden’s Girls School, 1989-1992)
Use linseed oil to thin
Use turpentine to clean
Lightly sketch out the desired image
Paint the highlights, then the colors, then the shadows
Repeat until image is aesthetically pleasing
Mr. Harris (Latin School, 1997-2001)
Start with a large bristle brush
Then use incrementally smaller bristle brushes
Switch to large soft brush
Then use incrementally smaller soft brushes
The face has cool undertones across the forehead and chin
And warm undertones across the cheekbones and nose tip
The human body tip-to-toe is the height of eight heads
The wingspan is equal to the height
The eyes are halfway between the top of head and bottom of chin
The nose is halfway between the center of eyes and bottom of chin
The mouth is halfway between the bottom of nose and bottom of chin
The head is egg-shaped
Samin Lama (Bhaktapur, Nepal, 2007-2008)
To prepare a thankga canvas:
Don’t breathe while the brush is on the canvas
(This also applies to soldering)
Time breaths with brushstrokes
Use no more paint than necessary
The image should shine clearly when back-lit
Ignore any distraction
Maintain posture
Sara Bright (UC Berkeley, 2007-2009)
[Mr. Harris'] bristle/soft brush strategy is not always best
Use the brush that best suits the attitude of the subject
Keep all your tools clean
Maintain a lightness
Squeak Carnwath (UC Berkeley, 2007-2009)
Paintballs are too violent and ugly to be called painting
To paint carelessly is to insult the entire history of painting
Mineral spirits are better than turpentine as a subtractive
And can be used as a non-retarding thinner
Unprimed canvases deteriorate after 10 years
Paint well-applied can disguise itself as any other medium
Katherine Sherwood (UC Berkeley, 2007-2009)
[Cannot yet be sufficiently summarized.]
Use linseed oil to thin
Use turpentine to clean
Lightly sketch out the desired image
Paint the highlights, then the colors, then the shadows
Repeat until image is aesthetically pleasing
Mr. Harris (Latin School, 1997-2001)
Start with a large bristle brush
Then use incrementally smaller bristle brushes
Switch to large soft brush
Then use incrementally smaller soft brushes
The face has cool undertones across the forehead and chin
And warm undertones across the cheekbones and nose tip
The human body tip-to-toe is the height of eight heads
The wingspan is equal to the height
The eyes are halfway between the top of head and bottom of chin
The nose is halfway between the center of eyes and bottom of chin
The mouth is halfway between the bottom of nose and bottom of chin
The head is egg-shaped
Samin Lama (Bhaktapur, Nepal, 2007-2008)
To prepare a thankga canvas:
Build a frame of four interlocked planks of wood wide enough to be rigid under pressure
Cut a canvas a hand-width narrower than the frame’s interior
Sew a finger-width hem around the canvas
Run twine through the hem, crosshatching over the corners of the frame
Use a leather needle to sew the canvas into the frame
Use a stitch four-fingers wide
Stretch the canvas tight and even into the frame, like a hide
Lap around until the canvas is stiff and springy
Bring a small pot of water and a hand-sized strip of animal skin glue to a boil over low heat
Do this outside, because it will stink
When the glue melts, add a fistful of clay
Stir over heat until it is smooth and spreadable, not too sticky
Add small amounts of clay and water as necessary
Lay the canvas on the ground with something clean but expendable, and rigid
We used plywood but cardboard works well
Take a rag and spread the warm primer evenly across the canvas
Take a smooth stone and rub the primer into the canvas
Apply firm pressure, using your whole arm
Flip the canvas over and repeat
Let dry between layers
Repeat until the surface is smooth and thin, like parchment
Cut a canvas a hand-width narrower than the frame’s interior
Sew a finger-width hem around the canvas
Run twine through the hem, crosshatching over the corners of the frame
Use a leather needle to sew the canvas into the frame
Use a stitch four-fingers wide
Stretch the canvas tight and even into the frame, like a hide
Lap around until the canvas is stiff and springy
Bring a small pot of water and a hand-sized strip of animal skin glue to a boil over low heat
Do this outside, because it will stink
When the glue melts, add a fistful of clay
Stir over heat until it is smooth and spreadable, not too sticky
Add small amounts of clay and water as necessary
Lay the canvas on the ground with something clean but expendable, and rigid
We used plywood but cardboard works well
Take a rag and spread the warm primer evenly across the canvas
Take a smooth stone and rub the primer into the canvas
Apply firm pressure, using your whole arm
Flip the canvas over and repeat
Let dry between layers
Repeat until the surface is smooth and thin, like parchment
Don’t breathe while the brush is on the canvas
(This also applies to soldering)
Time breaths with brushstrokes
Use no more paint than necessary
The image should shine clearly when back-lit
Ignore any distraction
Maintain posture
Sara Bright (UC Berkeley, 2007-2009)
[Mr. Harris'] bristle/soft brush strategy is not always best
Use the brush that best suits the attitude of the subject
Keep all your tools clean
Maintain a lightness
Squeak Carnwath (UC Berkeley, 2007-2009)
Paintballs are too violent and ugly to be called painting
To paint carelessly is to insult the entire history of painting
Mineral spirits are better than turpentine as a subtractive
And can be used as a non-retarding thinner
Unprimed canvases deteriorate after 10 years
Paint well-applied can disguise itself as any other medium
Katherine Sherwood (UC Berkeley, 2007-2009)
[Cannot yet be sufficiently summarized.]
Art Lessons from Humans (Photography)
My Father
Never have the subject directly centered
Use the right camera for the right job
Aperture is the dilation of the lens
Shutter speed is the length of time the lens is open, in tenths of a second
Focal point marks the distance from you to the subject
Ms. Ross (Latin School, 1997-2001)
Three ways to take a photo:
Fully com/posed
Right place, right time
Premeditated composition, waiting for the perfect moment
A tight aperture (high number) has a long depth of field (more is in focus)
A wide aperture (low number) has a short depth of field (less is in focus)
To prepare black & white film:
With your hands in a lightproof bag (even darkroom light will ruin undeveloped film)
Use a bottle opener to pry open the film canister
Slide the film onto the ridged spool of the developing tank
Encase the spool in the lightproof tank
Add chemicals and water as directed into the tank
Shaking carefully
Disposing of chemicals properly
Practiced, takes 5 minutes
Developed film is light-safe
To prepare color or slide film:
Is too difficult and not worth doing yourself, send them to a lab
To print on an enlarger:
Any errant light will ruin photo paper
Objects placed directly on paper will produce an image (Rayographs)
Place negative in holder, focus
Place photo paper on enlarger rack
Expose light (time is critical: longer exposure leads to a darker image)
Dodge and burn as necessary
Put photo paper in developer for around 30 seconds (time is critical, may vary)
Then stop bath for a minute (time not critical)
Then fix for four minutes (time is critical, may vary)
Then rinse for a minute (time not critical, image is now light-safe)
Then hang to dry (let dry fully)
Final prints should range from full black to full white
Digital photos are the wave of the future
Art Lessons from Humans (Drawing)
Mr. Bough (Latin School, 1997-2001)
“Draw what you see, not what you know”
“Look at the subject 90% of the time, the drawing 10%”
“Move your entire arm as you draw”
“Erasers are more dangerous than heroin”
"Draw one eyebrow hair at a time"
"Heads are egg-shaped"
Perspective / Vanishing point
Foreshortening
Golden Ratio
Nora Salzman (Latin School, 1997-2001)
Drawing pencils are unnecessary; any implement will do
Practice frequent, casual drawings
“Draw what you see, not what you know”
“Look at the subject 90% of the time, the drawing 10%”
“Move your entire arm as you draw”
“Erasers are more dangerous than heroin”
"Draw one eyebrow hair at a time"
"Heads are egg-shaped"
Perspective / Vanishing point
Foreshortening
Golden Ratio
Nora Salzman (Latin School, 1997-2001)
Drawing pencils are unnecessary; any implement will do
Practice frequent, casual drawings
Art Lessons from Robots
Mr. Springs (robot, built 2008)
Colors mix unpredictably
Linseed oil retards drying
Plain Ivory soap is good for getting paint out of things
Act on it quickly
Light is a noisy signal,
but slow to change in an empty room
A light sensor left in the dark will see random noise
And Nila alone in the dark,
Calculina (AI, built by Tom Lippincott 2010)
Acrylic paint dries in a matter of hours
Especially the cheap generic kind you bought
Nothing comes of putting down globs of primary colors
Never applied unmixed
And all rough materials must be selected and prepared
With time and care
(Well, most of this came from the visibly distraught
Squeak and Katherine during my formal critiques)
But the sound he made, like snoring, was sweet
And everyone liked the way his box body twitched from the servos
Nila (robot, built 2008)
Especially the cheap generic kind you bought
Nothing comes of putting down globs of primary colors
Straight out of the bottle
Onto a pre-stretched, pre-primed canvas
And hoping the robot mixes them well
Colors must be coaxed gently through hue and toneOnto a pre-stretched, pre-primed canvas
And hoping the robot mixes them well
Never applied unmixed
And all rough materials must be selected and prepared
With time and care
(Well, most of this came from the visibly distraught
Squeak and Katherine during my formal critiques)
But the sound he made, like snoring, was sweet
And everyone liked the way his box body twitched from the servos
Nila (robot, built 2008)
Colors mix unpredictably
Linseed oil retards drying
and spatters
and is hard to clean
Mineral spirits seep through layers and canvasand is hard to clean
Plain Ivory soap is good for getting paint out of things
Act on it quickly
Light is a noisy signal,
but slow to change in an empty room
A light sensor left in the dark will see random noise
And Nila alone in the dark,
jittering around the still-wet paint from the day,
and the days before, smearing the information together,
sort of seems to be dreaming
and the days before, smearing the information together,
sort of seems to be dreaming
Calculina (AI, built by Tom Lippincott 2010)
Random strokes coupled with a simple feedback mechanism will converge on a desirable result
UNIX Commands
change directory
cd \find_this_directory/sub_directory
/this_directory/sub_directory
list files
ls
list permissions
ls -l
change permissions
chmod -permission filename.ext
r, w, x (read, write, execute)
cd \find_this_directory/sub_directory
/this_directory/sub_directory
list files
ls
list permissions
ls -l
change permissions
chmod -permission filename.ext
r, w, x (read, write, execute)
The Four Laws of Thermodynamics
0. About thermal equilibrium
If two thermodynamic systems are separately in thermal equilibrium with a third, they are also in thermal equilibrium with each other.
1. About the conservation of energy
The change in the internal energy of a closed thermodynamic system is equal to the sum of the amount of heat energy supplied to or removed from the system and teh work done on or about the system. So, we can say (1) “Energy is neither created nor destroyed.”
2. About entropy
The total entropy of any isolated thermodynamic system always increases over time, approaching a maximum value or we can say, “In an isolated system, the entropy never decreases.” Another way to phrase this: Heat cannot spontaneously flow from a colder location to a hotter area— work is required to achieve this.
3. About the absolute zero of temperature
As a system asymptotically approaches absolute zero of temperature all processes virtually cease and the entropy of the system asymptotically approaches a minimum value; also stated as: “the entropy of all systems and of all states of a system is smallest at absolute zero” or equivalently, “it is impossible to reach the absolute zero of temperature by any finite number of processes.” Absolute zero, at which all activity would stop if it were possible to happen, is -273.15°C, or -459.67°F, or 0K.
If two thermodynamic systems are separately in thermal equilibrium with a third, they are also in thermal equilibrium with each other.
1. About the conservation of energy
The change in the internal energy of a closed thermodynamic system is equal to the sum of the amount of heat energy supplied to or removed from the system and teh work done on or about the system. So, we can say (1) “Energy is neither created nor destroyed.”
2. About entropy
The total entropy of any isolated thermodynamic system always increases over time, approaching a maximum value or we can say, “In an isolated system, the entropy never decreases.” Another way to phrase this: Heat cannot spontaneously flow from a colder location to a hotter area— work is required to achieve this.
3. About the absolute zero of temperature
As a system asymptotically approaches absolute zero of temperature all processes virtually cease and the entropy of the system asymptotically approaches a minimum value; also stated as: “the entropy of all systems and of all states of a system is smallest at absolute zero” or equivalently, “it is impossible to reach the absolute zero of temperature by any finite number of processes.” Absolute zero, at which all activity would stop if it were possible to happen, is -273.15°C, or -459.67°F, or 0K.
Lever
From French lever, “to raise”
A rigid object used with an appropriate fulcrum to realize a mechanical advantage.
Archemides said:
“Give me a place to stand, and I shall move the Earth with a lever.”
The ratio of the force applied to each end points of the lever is proportional to the ratio of the length of the lever arm measured between the fulcrum and the force’s application point at each end.
Class 1: The fulcrum is located between the applied force and the load
Class 2: The load is located between the fulcrum and the force
Class 3: The force is located between the fulcrum and the load
A rigid object used with an appropriate fulcrum to realize a mechanical advantage.
Archemides said:
“Give me a place to stand, and I shall move the Earth with a lever.”
The ratio of the force applied to each end points of the lever is proportional to the ratio of the length of the lever arm measured between the fulcrum and the force’s application point at each end.
M = Fd
where M is the moment, F is the force,
and d is the distance between the force and the fulcrum
F*LF = R*LR
where F is the force, LF is the distance between the application and the fulcrum
R is the resistance, and LR is the distance between the resistance and the fulcrum
Class 1: The fulcrum is located between the applied force and the load
Class 2: The load is located between the fulcrum and the force
Class 3: The force is located between the fulcrum and the load
Pulley
Reasons to use a pulley:
that may have a groove between two flanges along the edge
A rope, cable, belt, or chain usually runs over the wheel and inside the groove
if present.
Belt and pulley systems transmit mechanical power, torque, and speed across axes, and if the pulleys are of differing diameters, realize a mechanical advantage.
Rope and pulley systems transmit a linear motive force (in tension) to a load through one or more pulleys for the purpose of pulling the load.
A fixed pulley has a fixed axle
and is used to change the direction of the force on a rope
and has an MA = 1
A movable pulley has a free axle
and is used to multiply forces
and has an MA = 2
A block and tackle system uses a combination of fixed and movable
and has an MA > 2
- Change the direction of an applied force
- Transmit rotational motion
- Realize a mechanical advantage in either a linear or rotational system of motion
that may have a groove between two flanges along the edge
A rope, cable, belt, or chain usually runs over the wheel and inside the groove
if present.
Belt and pulley systems transmit mechanical power, torque, and speed across axes, and if the pulleys are of differing diameters, realize a mechanical advantage.
Rope and pulley systems transmit a linear motive force (in tension) to a load through one or more pulleys for the purpose of pulling the load.
A fixed pulley has a fixed axle
and is used to change the direction of the force on a rope
and has an MA = 1
A movable pulley has a free axle
and is used to multiply forces
and has an MA = 2
A block and tackle system uses a combination of fixed and movable
and has an MA > 2
Gear
Reasons to use a gear:
Gears are read left-to-right when counting ratios (left gear is bigger in a 2:1).
Gears are manufactured such that tooth count is more accurate than circumference in determining gear ratios.
To create large gear ratios, use a gear train.
Worm gears function as “one tooth” gears
and flip the axis of motion 90°.
A planetary gear system uses the same axis for both input and output gear
and is very rugged.
- Reverse the direction of rotation
- Change the speed of rotation
- Move rotational motion to a different axis
- Keep the rotation of two axes synchronized
Gears are read left-to-right when counting ratios (left gear is bigger in a 2:1).
Gears are manufactured such that tooth count is more accurate than circumference in determining gear ratios.
To create large gear ratios, use a gear train.
Worm gears function as “one tooth” gears
and flip the axis of motion 90°.
A planetary gear system uses the same axis for both input and output gear
and is very rugged.
The Four Known Fundamental Interactions
Electromagentism
Causes interaction between electrically charged particles
in areas called electromagnetic fields
And binds (negative) electrons to (positive) protons
which together form atoms
which together form molecules
which are categorized as elements
which together form chemicals
which together form everything we see
which together form molecules
which are categorized as elements
which together form chemicals
which together form everything we see
A changing electric field generates a magnetic field
and vice-versa
in a process called electromagnetic induction
in a process called electromagnetic induction
Strong Interaction
Causes the (netural) neutrons to bind to the (positive) protons and form the nucleus
and quarks to bind to gluons and form nucleons, etc
overriding electromagnetism
The strongest of the Interactions
overriding electromagnetism
The strongest of the Interactions
Weak Interaction
Causes radioactivity through beta decay
(the emission of electrons by neutrons or positrons by the protons in atomic nuclei)
And is due to the exchange of the heavy W and Z bosons
Gravitation
Causes dispersed matter to coalesce
And is due to the curvature of spacetime which governs the motion of inertial objects
Newton's simpler, still reliable theory states:
I deduced that the forces which keep the planets in their orbs must [be] reciprocally as the squares of their distances from the centers about which they revolve: and thereby compared the force requisite to keep the Moon in her Orb with the force of gravity at the surface of the Earth; and found them answer pretty nearly.
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