18,223 research outputs found
The ultimate tactics of self-referential systems
Mathematics is usually regarded as a kind of language. The essential behavior
of physical phenomena can be expressed by mathematical laws, providing
descriptions and predictions. In the present essay I argue that, although
mathematics can be seen, in a first approach, as a language, it goes beyond
this concept. I conjecture that mathematics presents two extreme features,
denoted here by {\sl irreducibility} and {\sl insaturation}, representing
delimiters for self-referentiality. These features are then related to physical
laws by realizing that nature is a self-referential system obeying bounds
similar to those respected by mathematics. Self-referential systems can only be
autonomous entities by a kind of metabolism that provides and sustains such an
autonomy. A rational mind, able of consciousness, is a manifestation of the
self-referentiality of the Universe. Hence mathematics is here proposed to go
beyond language by actually representing the most fundamental existence
condition for self-referentiality. This idea is synthesized in the form of a
principle, namely, that {\sl mathematics is the ultimate tactics of
self-referential systems to mimic themselves}. That is, well beyond an
effective language to express the physical world, mathematics uncovers a deep
manifestation of the autonomous nature of the Universe, wherein the human brain
is but an instance.Comment: 9 pages. This essay received the 4th. Prize in the 2015 FQXi essay
contest: "Trick or Truth: the Mysterious Connection Between Physics and
Mathematics
Marx, the labour theory of value and the transformation problem
This article reconsiders what Marx says about the transformation problem in Chapter IX of Capital Volume III, in the light of Marx's claim, made in Capital Volume I, that the value of a commodity is determined by the socially necessary labour time that goes into its production. The article criticises the traditional way of thinking about the transformation problem, according to which what Marx is doing in Chapter IX is considering the transformation of values into prices ('prices of production'). I argue that Marx's prices of production may be thought of as modified values. The discussion in Chapter IX is usually seen as a supplement to the labour theory of value. On this view its purpose is to explain how and why the prices of commodities sometimes deviate from their values. Against this view, the paper argues that Marx's remarks in Chapter IX can be seen as an elaboration on or development of the labour theory of value. It is a refinement of the account offered in Capital Volume I, which takes into consideration what Marx had in mind there when he introduced the notion of socially necessary as opposed to actual labour-time. The paper draws attention to the importance of Marx's distinction between the individual value of a commodity (determined by actual labour-time) and its social value (determined by socially necessary labour-time). It also draws attention to the methodological difficulties that are generated by any attempt to read Marx in this way
Quantum Fluctuations Driven Orientational Disordering: A Finite-Size Scaling Study
The orientational ordering transition is investigated in the quantum
generalization of the anisotropic-planar-rotor model in the low temperature
regime. The phase diagram of the model is first analyzed within the mean-field
approximation. This predicts at a phase transition from the ordered to
the disordered state when the strength of quantum fluctuations, characterized
by the rotational constant , exceeds a critical value . As a function of temperature, mean-field theory predicts a range of
values of where the system develops long-range order upon cooling, but
enters again into a disordered state at sufficiently low temperatures
(reentrance). The model is further studied by means of path integral Monte
Carlo simulations in combination with finite-size scaling techniques,
concentrating on the region of parameter space where reentrance is predicted to
occur. The phase diagram determined from the simulations does not seem to
exhibit reentrant behavior; at intermediate temperatures a pronounced increase
of short-range order is observed rather than a genuine long-range order.Comment: 27 pages, 8 figures, RevTe
ΠΠ±Π½Π°ΡΡΠΆΠ΅Π½ΠΈΠ΅ ΡΠ°ΡΡΠΈΡΠ½ΡΡ ΡΠ°Π·ΡΡΠ΄ΠΎΠ² ΠΈΠΌΠΏΡΠ»ΡΡΠ½ΡΠΌ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ
ΠΡΠΏΡΡΠΊΠ½Π°Ρ ΠΊΠ²Π°Π»ΠΈΡΠΈΠΊΠ°ΡΠΈΠΎΠ½Π½Π°Ρ ΡΠ°Π±ΠΎΡΠ° ΡΠΎΠ΄Π΅ΡΠΆΠΈΡ 124 Ρ., 68 ΡΠΈΡ., 13 ΡΠ°Π±Π»., 22 ΠΈΡΡΠΎΡΠ½ΠΈΠΊΠ°, 1 ΠΏΡΠΈΠ».
ΠΠ»ΡΡΠ΅Π²ΡΠ΅ ΡΠ»ΠΎΠ²Π°: ΠΈΠΌΠΏΡΠ»ΡΡΠ½ΡΠΉ ΠΌΠ΅ΡΠΎΠ΄, ΡΠ°ΡΡΠΈΡΠ½ΡΠΉ ΡΠ°Π·ΡΡΠ΄, ΠΎΠ±Π½Π°ΡΡΠΆΠ΅Π½ΠΈΠ΅, Π΄Π΅ΡΠ΅ΠΊΡ, Π½Π°ΡΠ³Π»Π΅ΡΠΎΠΆΠΈΠ²Π°Π½ΠΈΠ΅.
ΠΠ±ΡΠ΅ΠΊΡΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ: ΡΠ΅ΠΊΡΠΈΠΈ ΠΊΠΎΠ½Π΄Π΅Π½ΡΠ°ΡΠΎΡΠ° (90 ΠΏΠ€, 0,12 ΠΌΠΊΠ€, 700 ΠΏΠ€, 1100 ΠΏΠ€, 1500 ΠΏΠ€), ΠΏΡΠΎΠΏΠΈΡΡΠ²Π°ΡΡΠΈΠΉ ΡΠΎΡΡΠ°Π² (ΠΊΠ°ΡΡΠΎΡΠΎΠ²ΠΎΠ΅ ΠΌΠ°ΡΠ»ΠΎ).
Π¦Π΅Π»Ρ ΡΠ°Π±ΠΎΡΡ: ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄Π° Π΄Π»Ρ ΠΎΠ±Π½Π°ΡΡΠΆΠ΅Π½ΠΈΡ ΡΠ°ΡΡΠΈΡΠ½ΡΡ
ΡΠ°Π·ΡΡΠ΄ΠΎΠ² ΠΏΡΠΈ ΠΏΠΎΠΌΠΎΡΠΈ ΠΏΠΎΠ΄Π°Π²Π°Π΅ΠΌΠΎΠ³ΠΎ ΠΈΠΌΠΏΡΠ»ΡΡΠ½ΠΎΠ³ΠΎ Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΡ Π½Π° ΠΈΡΠΏΡΡΡΠ΅ΠΌΡΠΉ ΠΎΠ±ΡΠ΅ΠΊΡ.
ΠΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ ΠΈΡΠΏΡΡΠ°Π½ΠΈΡ ΠΏΠΎ ΠΎΠ±Π½Π°ΡΡΠΆΠ΅Π½ΠΈΡ ΡΠ°ΡΡΠΈΡΠ½ΡΡ
ΡΠ°Π·ΡΡΠ΄ΠΎΠ² ΠΏΡΡΠ΅ΠΌ ΠΏΠΎΠ΄Π°ΡΠΈ ΠΈΠΌΠΏΡΠ»ΡΡΠ° Ρ ΠΊΡΡΡΡΠΌ ΡΡΠΎΠ½ΡΠΎΠΌ Π½Π° ΠΈΡΠΏΡΡΡΠ΅ΠΌΡΠΉ ΠΎΠ±ΡΠ΅ΠΊΡ, Π² ΠΊΠΎΡΠΎΡΠΎΠΌ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎ ΠΏΠΎΡΠ²Π»Π΅Π½ΠΈΠ΅ ΡΠ°ΡΡΠΈΡΠ½ΡΡ
ΡΠ°Π·ΡΡΠ΄ΠΎΠ² (ΡΠ΅ΠΊΡΠΈΡ ΠΈΠΌΠΏΡΠ»ΡΡΠ½ΠΎΠ³ΠΎ ΠΊΠΎΠ½Π΄Π΅Π½ΡΠ°ΡΠΎΡΠ°). Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ ΠΏΠΎΡΠ²Π»Π΅Π½ΠΈΠ΅ ΡΠ°ΡΡΠΈΡΠ½ΡΡ
ΡΠ°Π·ΡΡΠ΄ΠΎΠ² ΠΈΠ·ΠΌΠ΅Π½ΡΠ΅Ρ ΡΠΎΡΠΌΡ ΡΠΎΠΊΠ° ΡΠ΅ΡΠ΅Π· ΠΈΡΠΏΡΡΡΠ΅ΠΌΡΠΉ ΠΎΠ±ΡΠ΅ΠΊΡ ΠΏΡΡΠ΅ΠΌ ΠΏΠΎΠ΄Π°ΡΠΈ Π½Π° ΠΎΠ±ΡΠ΅ΠΊΡ Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΡ Ρ ΠΊΡΡΡΡΠΌ ΡΡΠΎΠ½ΡΠΎΠΌ. Π Π°Π·Π»ΠΈΡΠ½Π°Ρ Π΅ΠΌΠΊΠΎIn the production, transportation and processing of biological resources different electrical equipment is used, the integral part of which are DC machines. Energy efficiency and reliability of the production depends on the drives. The breakdown even of one engine may stop the production process and consequently entail losses. One reason for the failure of the DC motors is insulation damage due to exposure to partial discharge, however, a partial discharge detection technique has not been developed yet. For early warning of failure of DC machines and reducing the cost of unplanned stoppage on the replacement of a failed motor it is proposed to detect partial discharge sat an early stage. There are many developments related to the detection of partial discharges. The majority of methods re
Patterning and process parameter effects in 3D suspension near-field electrospinning of nanoarrays
The extracellular matrix (ECM) contains nanofibrous proteins and proteoglycans. Nanofabrication methods have received growing interest in recent years as a means of recapitulating these elements within the ECM. Near-field electrospinning (NFES) is a versatile fibre deposition method, capable of layer-by-layer nano-fabrication. The maximum layer height is generally limited in layer-by-layer NFES as a consequence of electrostatic effects of the polymer at the surface, due to residual charge and polymer dielectric properties. This restricts the total volume achievable by layer-by-layer techniques. Surpassing this restriction presents a complex challenge, leading to research innovations aimed at increasing patterning precision, and achieving a translation from 2D to 3D additive nanofabrication. Here we investigated a means of achieving this translation through the use of 3D electrode substrates. This was addressed by in-house developed technology in which selective laser melt manufactured standing pillar electrodes were combined with a direct suspension near-field electrospinning (SNFES) technique, which implements an automated platform to manoeuvre the pillar electrodes around the emitter in order to suspend fibres in the free space between the electrode support structures. In this study SNFES was used in multiple operation modes, investigating the effects of varying process parameters, as well as pattern variations on the suspended nanoarrays. Image analysis of the nanoarrays allowed for the assessment of fibre directionality, isotropy, and diameter; identifying optimal settings to generate fibres for tissue engineering applications
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