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Particle behavior in systems of length less than the mean free path
Knudsen diffusion, named after Martin Knudsen, is a means of diffusion that occurs when the scale length of a system is comparable to or smaller than the
Knudsen_diffusion
Equation describing the flow of a fluid through a porous medium
(1980). Diffusion in Gases and Porous Media. New York: Plenum Press. Carrigy, N.; Pant, L. M.; Mitra, S. K.; Secanell, M. (2013). "Knudsen diffusivity
Darcy's_law
Dimensionless number relating to mean free path of a particle
The Knudsen number (Kn) is a dimensionless number defined as the ratio of the molecular mean free path length to a representative physical length scale
Knudsen_number
Danish physicist
Knudsen flow, Knudsen diffusion, Knudsen number, Knudsen layer and Knudsen gases. Also there is the Knudsen equation; two instruments, the Knudsen absolute
Martin_Knudsen
Transport of dissolved species from the highest to the lowest concentration region
equation, diffusion of thermal energy Itō diffusion, mathematisation of Brownian motion, continuous stochastic process. Knudsen diffusion of gas in long
Diffusion
Proportionality constant in some physical laws
gas; (dis) – dissolved. Atomic diffusion Effective diffusion coefficient Lattice diffusion coefficient Knudsen diffusion "CRC Press Online: CRC Handbook
Mass_diffusivity
Gas flow with a relatively large mean free molecular path
estimation, with the Knudsen number (Kn). If Kn > 10, the system is in free molecular flow, also known as Knudsen flow. Knudsen flow has been defined
Free_molecular_flow
Ratio of void volume and total volume of a porous material
adsorption analysis. Transport within mesopores is governed primarily by Knudsen diffusion. Macroporosity: Refers to pores with a diameter greater than 50 nm
Porosity
Measure of the ability of a porous material to allow fluids to pass through it
(about 0.01 to 0.1 μm at standard temperature and pressure). See also Knudsen diffusion and constrictivity. For example, measurement of permeability through
Permeability_(porous_media)
Topics referred to by the same term
diffusion Effusion of a gas through small holes Gaseous diffusion Itō diffusion Knudsen diffusion of particles from very small containers Osmosis, the movement
Diffusion_(disambiguation)
Synthetic membrane
membranes. Surface diffusion typically plays a larger role in the transport of molecules at lower temperatures. Knudsen diffusion also contributes to
Zeolite_membrane
Electrochemical process
increases as the measured surface area decreases whereas, molecular and Knudsen diffusion components remain constant. As a consequence, by controlling the carbon
CO_stripping
Parameter for diffusion and fluid flow in porous media
Constrictivity must be distinguished from the effects of Knudsen diffusion. Knudsen diffusion occurs when the particle interacts with the pore walls more
Constrictivity
Technology for splitting specific gases out of mixtures
25 to 40% oxygen per day. There are three main diffusion mechanisms. The first (b), Knudsen diffusion holds at very low pressures where lighter molecules
Membrane_gas_separation
Topics referred to by the same term
moving parts called a Knudsen pump. It is the currently accepted theory for the rotation of the Crookes radiometer. Diffusion in a temperature gradient
Thermal_diffusion
Experimental technique to study kinetics
response which is controlled only by Knudsen diffusion with a reactive gas response which is controlled by diffusion as well as adsorption and chemical
Temporal_analysis_of_products
doi:10.1016/j.ces.2003.08.004. Feres, R.; G.S. Yablonsky (2004). "Knudsen Diffusion and Random Billiards". Chemical Engineering Science. 59 (7): 1541–1556
Grigoriy_Yablonsky
Statistical mechanics framework
expressing deviations from local equilibrium as a perturbative series in Knudsen number Kn {\displaystyle {\text{Kn}}} , which is small if τ f ≪ τ ext {\displaystyle
Chapman–Enskog_theory
Vaporization of a liquid from its surface
boundary between the liquid state and the vapor state. Instead, there is a Knudsen layer, where the phase is undetermined. Because this layer is only a few
Evaporation
Effects of pore diffusion on Rate of heterogeneous chemical reaction
f {\displaystyle D_{eff}} is the effective diffusivity. Diffusion is usually in the Knudsen regime when average pore radius is less than 100 nm. For
Weisz–Prater_criterion
radiometer. Knudsen pump — a gas pump with no moving parts which functions via thermal transpiration. Thermophoresis (Soret effect) — diffusion of colloidal
Thermal_transpiration
tube Knapp's rule Knight shift Knudsen cell Knudsen diffusion Knudsen equation Knudsen flow Knudsen gas Knudsen layer Knudsen number Knut Ångström Kochen–Specker
Index_of_physics_articles_(K)
Term to describe newly enriched persons
She'll Be Invited Everywhere". Saturday Evening Post. Vol. 239. p. 35. Knudsen, Dean D. (1968). "Socialization to Elitism: A Study of Debutantes". The
Nouveau_riche
Process of a gas escaping through a small hole
moving, the more likely they are to pass through the effusion orifice. The Knudsen cell is used to measure the vapor pressures of a solid with very low vapor
Effusion
Low-Density Gases
can be classified as rarefied, the non-dimensional Knudsen number is usually calculated. The Knudsen number Kn {\displaystyle {\ce {\mathrm {Kn} }}} is
Rarefied_gas_dynamics
Block cipher
version of SHARK can be broken using an interpolation attack (Jakobsen and Knudsen, 1997). KHAZAD Square Vincent Rijmen, Joan Daemen, Bart Preneel, Anton
SHARK
Process by which heat is transferred within an object
Thermal conduction is the diffusion of thermal energy (heat) within one material or between materials in contact. The higher temperature object has molecules
Thermal_conduction
Infinitesimal volume of fluid within a fluid flow
length scales of the specific flow under consideration. This requires the Knudsen number to be small, as is also a pre-requisite for the continuum hypothesis
Fluid_parcel
Family of block ciphers
Confusion and diffusion Alex Biryukov, Christophe De Cannière, Gustaf Dellkrantz: Cryptanalysis of SAFER++. CRYPTO 2003: 195-211 Lars R. Knudsen: A Detailed
Secure and Fast Encryption Routine
Secure_and_Fast_Encryption_Routine
(where he published with J.P. Hirth in 1962 ‘’ Diffusional contribution to the total flow from a Knudsen cell’’) and then worked for the rest of his research
Walter_L._Winterbottom
Branch of physics
the Knudsen number, defined as the ratio of the molecular mean free path to the characteristic length scale, is evaluated. Problems with Knudsen numbers
Fluid_mechanics
Equation of statistical mechanics
treating the charge carriers in a material as a gas). See also convection–diffusion equation. The equation is a nonlinear integro-differential equation, and
Boltzmann_equation
Concentrating specific isotopes of a chemical element
of the heavy water. Often done with gases, but also with liquids, the diffusion method relies on the fact that in thermal equilibrium, two isotopes with
Isotope_separation
Hollow cavity found in the lungs
months but continue to develop until 3 years of age. To create a thinner diffusion barrier, the double-layer capillary network fuse into one network, each
Pulmonary_alveolus
American neuroscientist
cell.2024.07.041. PMID 39178853. Kim, S.; Wallace, M. L.; El-Rifai, M.; Knudsen, A. R.; Sabatini, B. L. (2022). "Co-packaging of opposing neurotransmitters
Bernardo_L._Sabatini
Figure in medieval Scandinavian romance
part 1, p. 1-60, 17. On the dating of the chronicle: Anders Leegaard Knudsen, Saxostudier og rigshistorie på Valdemar Atterdags tid, Kopenhagen 1994
Amleth
Block cipher
cryptography, KN-Cipher is a block cipher created by Kaisa Nyberg and Lars Knudsen in 1995. One of the first ciphers designed to be provably secure against
KN-Cipher
Electric potential difference between interior and exterior of a biological cell
proteins embedded in it. The membrane serves both as a capacitor and as a diffusion barrier to the movement of ions. Ion pumps actively push ions across the
Membrane_potential
Excess accumulation of fluid in the brain
Albanese A, Antonini A, Cossu G, Deuschl G, Eleopra R, Galati A, Hoffmann CF, Knudsen K, Landi A, Lanotte MM (November 2016). "Idiopathic delayed-onset edema
Cerebral_edema
Evolution of societies
'mentally digested' from those who influenced him. In short, as Hodgson and Knudsen point out, Veblen thinks: "the changing institutions in their turn make
Sociocultural_evolution
Block cipher
from the Data Encryption Standard (DES). Its design was presented by Lars Knudsen at the SAC conference in 1997, and submitted as a proposal to the AES contest
DEAL
Probabilistic problem-solving algorithm
rarefied gas dynamics, where the Boltzmann equation is solved for finite Knudsen number fluid flows using the direct simulation Monte Carlo method in combination
Monte_Carlo_method
Block cipher
secure against ordinary differential and linear cryptanalysis, in 1999 Lars Knudsen and Vincent Rijmen presented a differential chosen-ciphertext attack that
DFC_(cipher)
Overview of and topical guide to brain mapping
system. Cortical stimulation mapping Diffusion MRI (dMRI) – includes diffusion tensor imaging (DTI) and diffusion functional MRI (DfMRI). dMRI is a recent
Outline_of_brain_mapping
SMASH is a cryptographic hash function which was created by Lars R. Knudsen. SMASH comes in two versions: 256-bit and 512-bit. Each version was supposed
SMASH_(hash)
Block cipher
rejection when shortlisting candidates, is given in a paper (Rijmen & Knudsen 1999). It was found to be susceptible to an effective theoretical differential
LOKI97
How sound behaves in an enclosed space
the effects varying by frequency. Acoustic reflection, diffraction, and diffusion can combine to create audible phenomena such as room modes and standing
Room_acoustics
Suspension of fine solid particles or liquid droplets in a gas
occurs primarily in particles too large for consideration as aerosols. The Knudsen number of the particle define three different dynamical regimes that govern
Aerosol
594–605. doi:10.2307/3105275. JSTOR 3105275. S2CID 112733319. Gordon, xiii Knudsen, Toke. "Bridging the Gap Between Theory and Practice: Astronomical Instruments
Timeline of historic inventions
Timeline_of_historic_inventions
Manufacturing process
aircraft manufacturing. Other companies quickly followed. As William S. Knudsen (having worked at Ford, GM and the National Defense Advisory Commission)
Assembly_line
Block cipher invented by Joan Daemen and Vincent Rijmen
introduced together with a new form of cryptanalysis discovered by Lars Knudsen, called the "Square attack". The structure of Square is a substitution–permutation
Square_(cipher)
Marginal sea of the Atlantic Ocean
Archived from the original on 1 January 2016. Retrieved 2 January 2009. Knudsen, Daniel C.; Charles Greet; Michelle Metro-Roland; Anne Soper (2008). Landscape
North_Sea
Equations of motion for viscous fluids
internal layers in fluids appears for flow with high gradients. For large Knudsen number of the problem, the Boltzmann equation may be a suitable replacement
Navier–Stokes_equations
Type of fuel cell
the catalyst layer and improving the structure of the catalyst and gas diffusion layers (e.g. ), and (c) optimizing the design of the flow field and the
Direct_methanol_fuel_cell
Steel alloy resistant to corrosion
summarized on website of National Institutes of Health, retrieved 16 March 2020 Knudsen, L.E. and H. Burr, "Follow-up examination of Danish stainless steel welders
Stainless_steel
Interplay between observation, experiment, and theory in science
ISBN 978-0-691-04334-0. Translated to English by Karen Jelved, Andrew D. Jackson, and Ole Knudsen, (translators 1997). Peirce, C.S. – see Charles Sanders Peirce bibliography
Scientific_method
f {\displaystyle f} in the Boltzmann equation as a power series in the Knudsen number K n {\displaystyle \mathrm {Kn} } : f ( r , c , t ) = f ( 0 ) (
Burnett_equations
Atmospheric effect caused by the solar wind
4 May 2019. Nishimura, Y.; Gallardo-Lacourt, B.; Zou, Y.; Mishin, E.; Knudsen, D. J.; Donovan, E. F.; Angelopoulos, V.; Raybell, R. (16 April 2019).
Aurora
Algorithm that calculates all the round keys from the key
that are somewhat or completely different from the encryption functions. Knudsen and Mathiassen (2004) give some experimental evidence that indicate that
Key_schedule
Execution by multiple shooters on command
live or blank ammunition. This is believed to reinforce the sense of diffusion of responsibility among the firing squad members. It provides each member
Execution_by_firing_squad
Cryptographic algorithm
University of Denmark in 2007. PRESENT was designed by Andrey Bogdanov, Lars R. Knudsen, Gregor Leander, Christof Paar, Axel Poschmann, Matthew J. B. Robshaw,
PRESENT
Class of computational fluid dynamics methods
{\displaystyle K} is the Knudsen number, the Taylor-expanded LBE can be decomposed into different magnitudes of order for the Knudsen number in order to obtain
Lattice_Boltzmann_methods
Type of cryptanalytic attack
substitution–permutation networks. It was originally designed by Lars Knudsen as a dedicated attack against Square, so it is commonly known as the Square
Integral_cryptanalysis
2022. Zhavoronkov, Alex; Mamoshina, Polina; Vanhaelen, Quentin; Scheibye-Knudsen, Morten; Moskalev, Alexey; Aliper, Alex (2019). "Artificial intelligence
Applications of artificial intelligence
Applications_of_artificial_intelligence
Family of block ciphers
cryptanalysis became available, as well as some early analysis results by (Knudsen 1993a). This resulted in the design being changed to become LOKI91. LOKI
LOKI
Dutch mathematician
project was to describe rarefied flow up to and including intermediate Knudsen numbers (Kn~1) by a hyperbolic-relaxation system. This works well for subsonic
Bram_van_Leer
Form of cryptanalaysis
generalization of differential cryptanalysis, an attack against block ciphers. Lars Knudsen developed the technique in 1994. Whereas ordinary differential cryptanalysis
Truncated differential cryptanalysis
Truncated_differential_cryptanalysis
Large biological molecule that acts as a catalyst
Nelson Thornes Publishers. pp. 87–118. ISBN 978-0748760114. Faergeman NJ, Knudsen J (April 1997). "Role of long-chain fatty acyl-CoA esters in the regulation
Enzyme
{c_{p}\mu }{k}}} Ludwig Prandtl heat transfer (ratio of viscous diffusion rate over thermal diffusion rate) Pressure coefficient CP C p = p − p ∞ 1 2 ρ ∞ V ∞
Dimensionless numbers in fluid mechanics
Dimensionless_numbers_in_fluid_mechanics
Early unclassified symmetric-key block cipher
Heidelberg. pp. 1–22. doi:10.1007/978-3-540-28628-8_1. ISBN 9783540226680. Knudsen, Lars R.; Mathiassen, John Erik (2000-04-10). "A Chosen-Plaintext Linear
Data_Encryption_Standard
American geophysicist and administrator (1902–1973)
low-voltage arcs, particularly the oscillatory phenomena arising in the diffusion of electrons against low-voltage fields. He continued this line of work
Carl_Eckart
Block cipher
to Rijndael. Serpent was designed by Ross Anderson, Eli Biham, and Lars Knudsen. Like other AES submissions, Serpent has a block size of 128 bits and supports
Serpent_(cipher)
Concept in fluid dynamics
inaccurate. For such examples, this change is driven by an increasing Knudsen number, which implies increasing rarefaction, and gradual failure of the
No-slip_condition
Branch of dynamics concerned with studying the motion of air
accurate method of solving the problem than is continuum aerodynamics. The Knudsen number can be used to guide the choice between statistical mechanics and
Aerodynamics
Traditional maritime greeting
norske ordbok. 4. Aufl. Oslo 1994, ISBN 82-573-0312-7 s. v. ohoi. Trygve Knudsen, Alf Sommerfelt: Norsk riksmålsordbok. Bd. 3, Oslo 1947 s. v. ohoi Svenska
Ahoy
Method of a dimension reduction
Compact Multi-Linear Pooling" [1]. IEEE Access, Vol. 5. 2017. Ahle, Thomas; Knudsen, Jakob (2019-09-03). "Almost Optimal Tensor Sketch". ResearchGate. Retrieved
Count_sketch
Dialect spoken in the Great Lakes region
2020-09-30. Kashian, Jackie (October 2010). "TDF Ep 6 - Jimmy Dore and Matt Knudsen". Uncut. Archived from the original on 2022-11-27. Retrieved 2022-11-27
Inland Northern American English
Inland_Northern_American_English
United States legislation
Service Reform Act of 1978; Statement on signing S. 2640 into law". 1978. Knudsen, Steven; Jakus, Larry; Metz, Maida (1979). "The civil service reform act
Civil Service Reform Act of 1978
Civil_Service_Reform_Act_of_1978
Family of block ciphers
according to a variant of the wide-trail strategy. Cryptanalysis by Lars Knudsen and Håvard Raddum in April 2001 showed that "indirect mode" NOEKEON was
NOEKEON
Type of cryptanalytic attack
special case of the more general case of higher order derivates. Lars Knudsen, in the same year, was able to show how the concept of higher order derivatives
Higher-order differential cryptanalysis
Higher-order_differential_cryptanalysis
Migraine associated with an ischemic brain lesion
1161/01.STR.15.2.271. PMID 6230778. S2CID 18475833. Hedman, C.; Winther, K.; Knudsen, J. B. (1988). "Platelet function in classic migraine during attack-free
Migrainous_infarction
Cryptographic attack
Known-key distinguishing attacks were first introduced in 2007 by Lars Knudsen and Vincent Rijmen in a paper that proposed such an attack against 7 out
Known-key distinguishing attack
Known-key_distinguishing_attack
Assessment of Chernobyl's impact on Earth since 1986
Germany: Springer Science and Media. pp. 160–162. ISBN 978-0-7923-0601-6. Knudsen, L. B. (1991). "Legally-induced abortions in Denmark after Chernobyl".
Effects of the Chernobyl disaster
Effects_of_the_Chernobyl_disaster
Block cipher
cryptanalysis can break NUSH with less effort than a brute force attack. Lars Knudsen, Håvard Raddum (2001-03-07). "A first report on Whirlpool, NUSH, SC2000
NUSH
Block cipher
pp. 201–212. Archived from the original (PDF) on July 23, 2004. Lars Knudsen and Vincent Rijmen (August 1997). "Two Rights Sometimes Make a Wrong" (PDF/PostScript)
Akelarre_(cipher)
Microscopic solid or liquid matter suspended in the Earth's atmosphere
Mshamu, Salum; Deen, Jacqueline; Pell, Christopher; Seidlein, Lorenz von; Knudsen, Jakob; Bøjstrup, Thomas Chevalier (7 January 2025). "Acceptability of
Particulate_matter
Exploitation of impossible differences in block ciphers
probability 0) at some intermediate state of the cipher algorithm. Lars Knudsen appears to be the first to use a form of this attack, in the 1998 paper
Impossible differential cryptanalysis
Impossible_differential_cryptanalysis
Area of applied mathematics
reactions", Chemical Engineering Science, 66:5388–5399, 2011. E. Feliu, M. Knudsen and C. Wiuf., "Signaling cascades: Consequences of varying substrate and
Chemical reaction network theory
Chemical_reaction_network_theory
General form of cryptanalysis applicable primarily to block ciphers
ISBN 978-3-540-57340-1. S2CID 6188138. Archived from the original on 2005-04-05. Knudsen LR, Robshaw M (2011). "Differential Cryptanalysis: The Idea". The Block
Differential_cryptanalysis
How nuclear fuel behaves during a reactor accident
burnup was 65 GWd t−1) which was heated in a Knudsen cell has been repeated. Fuel was heated in the Knudsen cell both with and without preoxidation in oxygen
Behavior of nuclear fuel during a reactor accident
Behavior_of_nuclear_fuel_during_a_reactor_accident
NASA atmospheric mission to Venus (1978)
1126/science.205.4401.102. JSTOR 1748530. PMID 17778917. S2CID 25337442. Knudsen, W. C.; Spenner, K.; Whitten, R. C.; Spreiter, J. R.; Miller, K. L.; Novak
Pioneer_Venus_Multiprobe
Capacity of a material to conduct heat
environment to the cold one as the temperature difference is equalized by diffusion. This is quantified in terms of a heat flux q {\displaystyle q} , which
Thermal conductivity and resistivity
Thermal_conductivity_and_resistivity
Block cipher
doi:10.1007/BFb0028479. ISBN 978-3-540-63696-0. Retrieved 2018-10-10. Knudsen, Lars R.; Rijmen, Vincent; Rivest, Ronald L.; Robshaw, Matthew J. B. (1998-08-16)
RC2
Budugur Lakshminarayana Fluid dynamics and Heat Transfer by James George Knudsen, Donald La Verne Katz Turbomachinery: Design and Theory (Marcell Dekker)
Three-dimensional losses and correlation in turbomachinery
Three-dimensional_losses_and_correlation_in_turbomachinery
Class of membrane-less organelles within biological cells
and of the molecular forces brought into play by solution, osmosis, diffusion, cohesion, and crystallization." The primordial soup theory of the origin
Biomolecular_condensate
NASA orbiter mission to Venus (1978–1992)
developed at the Lockheed Palo Alto Research Laboratory (LPARL), with W. Knudsen as the principal investigator. This instrument weighed 2.8 kilograms and
Pioneer_Venus_Orbiter
Vast body of ice in Greenland, Northern Hemisphere
the original on 18 July 2023. Retrieved 2 October 2022. Strunk, Astrid; Knudsen, Mads Faurschou; Egholm, David L. E; Jansen, John D.; Levy, Laura B.; Jacobsen
Greenland_ice_sheet
Scientific analysis
Neutral red, a weak cationic dye penetrates cellular membranes by non-diffusion and accumulates intercellularly in lysosomes. Viable cells take up the
In_vitro_toxicology
Thin semiconductors
heating up the material at UHV pressures. The evaporation cells are either Knudsen cells or electron beam evaporation based, depending on the materials; electron
Transition metal dichalcogenide monolayers
Transition_metal_dichalcogenide_monolayers
2020-07-31. Retrieved 2012-06-29. Karen Jelved, Andrew D. Jackson, and Ole Knudsen, (1997) translators for Selected Scientific Works of Hans Christian Ørsted
History_of_scientific_method
KNUDSEN DIFFUSION
KNUDSEN DIFFUSION
KNUDSEN DIFFUSION
Girl/Female
Muslim
Gold
Boy/Male
Hindu
Boy/Male
Indian, Punjabi, Sikh
Victory of Supreme
Boy/Male
Tamil
Vishnudutt | விஷà¯à®¨à¯à®¤à¯à®¤à¯à®¤
Gift of Lord Vishnu
Boy/Male
Hindu
Scorcher of all
Girl/Female
Bengali, Gujarati, Hindu, Indian, Kannada, Malayalam, Marathi
The Start; One of the Name of Goddess Lakshmi; Facet
Boy/Male
Tamil
Bathing to God, Shower of milk, Water over An idol
Boy/Male
Hindu
The won who wins over desires
Boy/Male
Indian
Another name of God, Pile, Treasury
Boy/Male
Danish
Son of Niel.
KNUDSEN DIFFUSION
KNUDSEN DIFFUSION
KNUDSEN DIFFUSION
KNUDSEN DIFFUSION
KNUDSEN DIFFUSION
n.
The emission and diffusion of rays of light.
n.
The act of radiating, or the state of being radiated; emission and diffusion of rays of light; beamy brightness.
n.
One opposed to the diffusion of knowledge; an obscuriantist.
n.
The act of disseminating, or the state of being disseminated; diffusion for propagation and permanence; a scattering or spreading abroad, as of ideas, beliefs, etc.
n.
An association of underwriters and others in London, for the collection and diffusion of marine intelligence, the insurance, classification, registration, and certifying of vessels, and the transaction of business of various kinds connected with shipping.
n.
The spreading abroad, or extension, of anything; diffusion; dissemination; as, the propagation of sound; the propagation of the gospel.
a.
Prepared by diffusion through an animal membrane; as, dialyzed iron.
n.
The act of passing from place to place or person to person; free diffusion; transmission.
n.
The act of passing by osmosis through animal membranes, as in the distribution of poisons, gases, etc., through the body. Unlike absorption, diffusion may go on after death, that is, after the blood ceases to circulate.
n.
The act of diffusing, or the state of being diffused; a spreading; extension; dissemination; circulation; dispersion.
n.
The extent to which anything circulates or is circulated; the measure of diffusion; as, the circulation of a newspaper.
n.
The separation of different substances in solution, as crystalloids and colloids, by means of their unequal diffusion, especially through natural or artificial membranes.