objet technique page 34

So two examples tend to show that the differentiation goes in the same sense as the condensation of multiple functions in the same structure, because the differentiations of structures within the system of reciprocal cuasaltities permits the elimination (by integrating them into functionality) of the secondary effects that were once obstacles. The specialization of every structure is a specialisation of a functional positive synthesis, liberated of the secondary effects unresearched that ameliorates the function:

The technical object progresses by an interior redistribution of compatable funtions and unities, by replacing the unpredictability or the antagonism of the primitive distribution. The specialization is not acheived function by function, rather synergie by synergie; it is the synergetic group of functions and not a singular function that constitutes a true sub assembly of a technical object.....

In this way and for this reason, while the technical object becomes concrete, a function coul be filled by several assoicated structures synergetically, wheras in the primitive technical object and abstracte each structure is tasked to answer to a difined function and genrally a limit. The essence of conretisation of the technical object is in the organisation of functional sub assemblies in the total function; by way of this prinicpal, we can understand in what sense operates the redistribution of of functions in the network of different structures, both within the abstract and concrete opbjects: every structure responds to several functions; but in the abstract technical object, it only responds to a single, positive and integrated function within the assembly; in the concreted technical object, all of the functions respond to the function thant answer to an assembly. The marginal consequences of the function, eliminated or attenuated by adjustments to the abstract technical object, these are stages to the evolution of the technical object.

Crookes Tube

Crookes tube

Historically, the first X-ray tube was invented by sir William Crookes. It was used to make a visible fluorescence on minerals. The Crookes tube is also called discharge tube or cold cathode tube.

It is a glass bulb with around a thousandth of sea-level atmospheric pressure of air (approximately 100 pascals or 1 torr). It contains an aluminum cathode with a curved shape to concentrate the electron flow on the anode, or "target".

A high tension (known in the US as voltage) is made between the electrodes; this induces an ionization of the residual air, and thus an electron flow or "discharge" from the cathode to the anode. When these electrons hit the target, they are slowed down, producing the X-rays (Bremsstrahlung and X-ray fluorescence of the target).

This tube can not produce X-rays continuously. It is no longer used on modern devices.

See also Crookes tube and glow discharge tube.

[edit] Coolidge tube

Coolidge side-window tube (scheme)

• K: filament
• A: anode
• W_in and W_out: water inlet and outlet of the cooling device (C)

The Crookes tube was improved by William Coolidge in 1913. The Coolidge tube, also called hot cathode tube, is the most widely used. It works with a very good quality vacuum (about 10^-4 Pa, or 10^-6 Torr).

In the Coolidge tube, the electrons are produced by thermionic effect from a tungsten filament heated by an electric current. The filament is the cathode of the tube. The high voltage potential is between the cathode and the anode, the electrons are thus accelerated, and then hit the anode.

There are two designs: end-window tubes and side-window tubes.

In the end-window tubes, the filament is around the anode, the electrons have a curved path.

What is special about side-window tubes is:

• An Electrostatic Lens to focus the beam onto a very small spot on the anode
• The anode is specially designed to dissipate the heat and wear resulting from this intense focused barrage of electrons:
  • Mechanically spun to increase the area heated by the beam.
  • Cooled by circulating coolant.
• The anode is precisely angled at 1-20 degrees off perpendicular to the electron current so as to allow escape of some of the X-ray photons which are emitted essentially perpendicular to the direction of the electron current.
• The anode is usually made out of tungsten or molybdenum.
• The tube has a window designed for escape of the generated X-ray photons.

The power of a Coolidge tube usually ranges from 1 to 4 kW.

Crookes Tube

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Crookes Tube Schematic (hot cathode variation)

The low voltage power supply (A) is connected to heat the cathode (C). The higher voltage power supply (B) energizes the phosphor-coated anode (P). The mask (M) is connected to the cathode potential and its image is seen on the phosphor as a non-glowing area. This tube may be built without supply A by using a cold cathode

The Crookes tube is an evacuated glass cone with 3 node elements (one anode and two cathodes). It is an invention of the 19th century scientist William Crookes and is an evolutionary development of the earlier Geissler tube.

Crookes Tube Schematic (hot cathode variation)

The low voltage power supply (A) is connected to heat the cathode (C). The higher voltage power supply (B) energizes the phosphor-coated anode (P). The mask (M) is connected to the cathode potential and its image is seen on the phosphor as a non-glowing area. This tube may be built without supply A by using a cold cathode

The Crookes tube was designed to explore phosphorescent effects observed in the Geissler tubes — at high vacuum any phosphorescent material within the low pressure envelope would glow, but only at one terminal. The excitation of the phosphor was attributed by Crookes to what he called cathode rays, and which are now interpreted to be particles rather than rays; these particles are electrons.

At the small end of a glass cone, an electrically heated wire, called the cathode, produces electrons. At the opposite end, a phosphor coated screen forming an anode is connected to the positive terminal of a voltage source of modest voltage (a few hundred volts), whose negative end is connected to the cathode. In between the cathode and the anode is placed a third element, a flat plate with some distinctive shape (the shadow mask), also connected to the cathode. When the appropriate voltages are applied to the various elements the screen will be seen to glow. A non-glowing image of the shadow mask will be imposed upon the screen.

The "music" of slot/pinball electro-mechanics

Daniel Vera, of Helsinki's Association Experimental Electronics, has a cool Flickr set and a number of YouTube vids (linked from Flickr) of rusty n' dusty components of pinball and slot machines being resuscitate and turned into clacking circuit-bent sequencers.

Rebecca Stern (MAKE and CRAFT author!) has a cool project sensing "squeeze" she writes -

I'm researching squeeze sensing as a mode of tactile interface. Here I will cover the process of developing a squeezeable sensor and the firmware/software concerns associated with interpreting the data from the sensor. This fulfills the "sensor project" for my class called Computational Principles in Media Arts taught in AME at ASU by Todd Ingalls and Hari Sundaram.

First off, how do we sense "squeeze?" People squeeze all kinds of things: lemons, steering wheels, loved ones, toothpaste and other toiletries, pimples, stress balls, hand exercisers. I would like to focus on the latter two, which provide a therapeutic activity for those with Repetitive Strain Injury (RSI). Using flex sensors arranged in a certain pattern on a spherical object, in this case a rubber dog toy, one can capture whenever the ball is squeezed.Sensing squeeze - Link.

Why I eyes ya

autopoeitic machines

Autopoietic machines undertake an incessant process of replacement of their components as they must continually compensate for the external perturbations to which they are exposed. (40)

Thus we will view autopoiesis from the perspective of the onto genesis and phlyogenesis proper to a mecanosphere superposed on the biosphere.(40
)

The phylogenetic evolution of machinism is expressed, at a primary level, by the fact that machines appear across "generations, " one suppressing the other as it becomes obsolete.

It is at the intersection of heterogeneous machini Universes, of different dimensions and with unfamiliar ontolol ical textures, radical innovations and once forgotten, the reactivated, ancestral machinic lines, that the movement i history singularises itself.

The man-machine alterity is thus inextricably linked to machine-machine alterity which operates in relations of cor plementarity or agonistic relations (between war machines) again in the relations of parts or apparatuses. (41)

The reproducibility of the machine is not a pure programmed repetition. The scansions of upture and indifferentiation, which uncouple a model from jany support, introduce their own share of both ontogenetic and phylogenetic difference.

The relations of technological machines between themselves, and the way their respective parts fit together, presuppose a formal serialisation and a certain perdition of their singularity - stronger than that of living machines - correlative to a distance between the machine manifested in energetico-spatio-temporal coordinates and the diagrammatic machine which develops in more deterritorialised coordinates.

The diagrammatic and its editions, example the key scenario.

I call this operation d alised smoothing and it applies as much to the normal the machine's constitutive materials as it does to thei and functional description.

Machinic Alterity and its forms
We have already encountered a certain number of registers of machinic alterity:

- the alterity of proximity between different machinE between different parts of the same machine;

- the alterity of an internal, material consistency;

- the alterity of formal, diagrammatic consistency; - the alterity of the evolutionary phylum;

- the agonistic alterity between machines of war, whose longation we could associate with the "auto-agonistic" ali of desiring machines which tend towards their own collar and abolition.

Another form of alterity which has only been appro very indirectly, is the alterity of scale, or fractal alterity, , (45)

Multivalence of Alterity
Example: the African legba: pile of sand of multipurpose and heterogenous purposes layered.