scholarly journals TOADS: A Two-Dimensional Open-Ended Architectural Database System

2001 ◽  
Vol 10 (2) ◽  
pp. 175-192
Author(s):  
Samuel Madden ◽  
Thomas E. von Wiegand
Keyword(s):  
Virtual Environments ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Interior Space ◽  
Acquisition Device ◽  
Innovative Tool ◽  
Transparent Windows ◽  
Narrow Bands

The TOADS system is an innovative tool for building interior-space virtual environments (VEs) in two dimensions. Existing VE design tools typically operate in three dimensions, which makes it difficult to manipulate objects on the inherently two-dimensional computer screen. TOADS allows nearly the same functionality as those three-dimensional systems in an easy-to-use, two-dimensional environment. Users edit and enhance DXF floorplans with height and texture information. The software includes an inference engine that automatically identifies doors in the floorplan and generates openable polygons in the final environment. It also includes a sophisticated mechanism for embedding complex textures, such as transparent windows, at arbitrary heights in wall polygons. The entire interface is integrated with software that drives a custom texture-acquisition device. This device consists of a rack-mounted camera that captures narrow bands of textures and tiles them together to form long, continuous swaths of texture. This paper summarizes these tools and their function, and presents examples of environments that were generated with them.

Compressible magnetoconvection in three dimensions: planforms and nonlinear behaviour

1995 ◽  
Vol 305 ◽  
pp. 281-305 ◽  
Author(s):  
P. C. Matthews ◽  
M. R. E. Proctor ◽  
N. O. Weiss
Keyword(s):  
Magnetic Field ◽  
Shear Flow ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Nonlinear Behaviour ◽  
Two Dimensional ◽  
Horizontal Shear ◽  
Mean Flow ◽  
The Magnetic Field

Convection in a compressible fiuid with an imposed vertical magnetic field is studied numerically in a three-dimensional Cartesian geometry with periodic lateral boundary conditions. Attention is restricted to the mildly nonlinear regime, with parameters chosen first so that convection at onset is steady, and then so that it is oscillatory.Steady convection occurs in the form of two-dimensional rolls when the magnetic field is weak. These rolls can become unstable to a mean horizontal shear flow, which in two dimensions leads to a pulsating wave in which the direction of the mean flow reverses. In three dimensions a new pattern is found in which the alignment of the rolls and the shear flow alternates.If the magnetic field is sufficiently strong, squares or hexagons are stable at the onset of convection. Both the squares and the hexagons have an asymmetrical topology, with upflow in plumes and downflow in sheets. For the squares this involves a resonance between rolls aligned with the box and rolls aligned digonally to the box. The preference for three-dimensional flow when the field is strong is a consequence of the compressibility of the layer- for Boussinesq magnetoconvection rolls are always preferred over squares at onset.In the regime where convection is oscillatory, the preferred planform for moderate fields is found to be alternating rolls - standing waves in both horizontal directions which are out of phase. For stronger fields, both alternating rolls and two-dimensional travelling rolls are stable. As the amplitude of convection is increased, either by dcereasing the magnetic field strength or by increasing the temperature contrast, the regular planform structure seen at onset is soon destroyed by secondary instabilities.

[Ni(cyclam)(OCOR)2], a finite molecular complex: hydrogen-bonded supramolecular aggregation in one, two and three dimensions, and coordination polymers in one and two dimensions

2001 ◽  
Vol 58 (1) ◽  
pp. 78-93 ◽  
Author(s):  
Choudhury M. Zakaria ◽  
George Ferguson ◽  
Alan J. Lough ◽  
Christopher Glidewell
Keyword(s):  
Hydrogen Bonding ◽  
Coordination Polymer ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Compound I ◽  
Supramolecular Aggregation ◽  
Linear Coordination

In the complexes [Ni(cyclam)(OCOR)2] (cyclam = 1,4,8,11-tetraazacyclotetradecane), where (RCOO)− is 2-naphtho-ate [bis-(2-naphthoato)-1,4,8,11-tetraazacyclotetradecanenickel(II), (I), monoclinic P21/c, Z′ = 0.5], 3,5-dinitrobenzoate [bis-(3,5-dinitrobenzoato)-1,4,8,11-tetraazacyclotetradecanenickel(II), (II), triclinic P\bar 1, Z′ = 0.5], 4-nitrobenzoate [bis-(4-nitrobenzoato)-1,4,8,11-tetraazacyclotetradecanenickel(II), (III), monoclinic P21/n, Z′ = 0.5], 3-hydroxybenzoate [bis-(3-hydroxybenzoato)-1,4,8,11-tetraazacyclotetradecanenickel(II), (IV), monoclinic P21/c, Z′ = 0.5] and 4-aminobenzo-ate [bis-(4-aminobenzoato)-1,4,8,11-tetraazacyclotetradecanenickel(II), (V), monoclinic C2/c, Z′ = 0.5], the Ni lies on a centre of inversion with monodentate carboxylato ligands occupying trans sites. Compound (I) consists of isolated molecules. In (II) and (III), N—H...O hydrogen bonds link the complexes into chains. Compounds (IV) and (III) form two- and three-dimensional structures generated entirely by hard hydrogen bonds. The 5-hydroxyisophthalate(2−) anion forms a hydrated complex, [Ni(cyclam)(5-hydroxyisophthalate)(H2O)]·4H2O {[aqua-(5-hydroxyisophthalato)-1,4,8,11-tetraazacyclotetradecanenickel(II)] tetrahydrate, (VI), monoclinic Cc, Z′ = 1}, in which the monodentate carboxylato ligand and a water molecule occupy trans sites at Ni: extensive hydrogen bonding links the molecular aggregates into a three-dimensional framework. The terephthalate(2−) anion forms a hydrated linear coordination polymer {catena-poly[terephthalato-1,4,8,11-tetraazacyclotetradecanenickel(II)] monohydrate, (VII), monoclinic C2/c, Z′ = 0.5}. In 1,2,4,5-benzenecarboxylate tris[1,4,8,11-tetraazacyclotetradecanenickel(II)] diperchlorate hydrate (VIII), [Ni(cyclam)]3·[1,2,4,5-benzenetetracarboxylate(4−)]·[ClO4]2·-[H2O]3, there are two distinct Ni sites: [Ni(cyclam)]2+ and centrosymmetric [C10H2O8]4− units form a two-dimensional coordination polymer, whose sheets are linked by centrosymmetric [Ni(cyclam)(H2O)2]2+ cations.

Instability of pressure-driven gas–liquid two-layer channel flows in two and three dimensions

2018 ◽  
Vol 849 ◽  
pp. 1-34 ◽  
Author(s):  
Lennon Ó Náraigh ◽  
Peter D. M. Spelt
Keyword(s):  
Flow Pattern ◽  
Linear Theory ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Channel Flows ◽  
Three Dimensions ◽  
Nonlinear Behaviour ◽  
Two Dimensional ◽  
Vorticity Field ◽  
Flow Pattern Map

We study unstable waves in gas–liquid two-layer channel flows driven by a pressure gradient, under stable stratification, not assumed to be set in motion impulsively. The basis of the study is direct numerical simulation (DNS) of the two-phase Navier–Stokes equations in two and three dimensions for moderately large Reynolds numbers, accompanied by a theoretical description of the dynamics in the linear regime (Orr–Sommerfeld–Squire equations). The results are compared and contrasted across a range of density ratios $r=\unicode[STIX]{x1D70C}_{liquid}/\unicode[STIX]{x1D70C}_{gas}$. Linear theory indicates that the growth rate of small-amplitude interfacial disturbances generally decreases with increasing $r$; at the same time, the cutoff wavenumbers in both streamwise and spanwise directions increase, leading to an ever-increasing range of unstable wavenumbers, albeit with diminished growth rates. The analysis also demonstrates that the most dangerous mode is two-dimensional in all cases considered. The results of a comparison between the DNS and linear theory demonstrate a consistency between the two approaches: as such, the route to a three-dimensional flow pattern is direct in these cases, i.e. through the strong influence of the linear instability. We also characterize the nonlinear behaviour of the system, and we establish that the disturbance vorticity field in two-dimensional systems is consistent with a mechanism proposed previously by Hinch (J. Fluid Mech., vol. 144, 1984, p. 463) for weakly inertial flows. A flow-pattern map constructed from two-dimensional numerical simulations is used to describe the various flow regimes observed as a function of density ratio, Reynolds number and Weber number. Corresponding simulations in three dimensions confirm that the flow-pattern map can be used to infer the fate of the interface there also, and show strong three-dimensionality in cases that exhibit violent behaviour in two dimensions, or otherwise the development of behaviour that is nearly two-dimensional behaviour possibly with the formation of a capillary ridge. The three-dimensional vorticity field is also analysed, thereby demonstrating how streamwise vorticity arises from the growth of otherwise two-dimensional modes.

In Search of Dominance: The Case of the Missing Dimension

2005 ◽  
Vol 100 (2) ◽  
pp. 559-566 ◽  
Author(s):  
Arthur E. Stamps
Keyword(s):  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Dimensional Theory

Some previous researchers have found that affect can be described in terms of two dimensions (pleasure and arousal), while others have noted three dimensions are needed (pleasure, arousal, and dominance). The competing claims were tested by creating stimuli with factors previously demonstrated to elicit responses of arousal or dominance, asking respondents to rate the stimuli, and contrasting correlations between ratings and the stimulus factors. Under the two-dimensional theory, the planned contrasts should be zero, while under the three-dimensional theory, the planned contrasts should be nonzero. Results supported the three-dimensional model.

scholarly journals Contemporary Nepali Arts: Blurring the Boundaries among Art Genres

2020 ◽  
pp. 48-56
Author(s):  
Yam Prasad Sharma
Keyword(s):  
Visual Art ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Verbal Art ◽  
Music Drama ◽  
Real Objects ◽  
And Performance ◽  
Dimensional Surface

Some contemporary Nepali artworks have blurred the boundaries among different art genres like sculpture, painting, music, drama, photography and literature. In a single artwork, we can view the elements of two or more art forms. Three dimensional real objects are put on the two dimensional surface like canvas. Three dimensions are the special characteristics of sculpture whereas there are only two dimensions in painting. Three dimensions in the painting are illusions created by the use of light and shade, and gradation of colors. Artists use photographs and paintings simultaneously in the same work. They take references from photographs and present them in canvas. They also present their paintings, sculptures and photographs along with music, recitation of poems and performance. Some of their canvases present painting and poem side by side in the single space. Both visual art and verbal art coexist in the single canvas. The artists’ creative urge goes beyond all boundaries, codes and established rules of arts. They do not follow the conventional techniques of creating arts. They experiment with forms, techniques, contents and medium. A single artwork has its own way of creation which may not be applicable to other artworks created by the same artist. The artist does not follow these trends but his work may set the new trend for other artists.

Inertial-range transfer in two- and three-dimensional turbulence

1971 ◽  
Vol 47 (3) ◽  
pp. 525-535 ◽  
Author(s):  
Robert H. Kraichnan
Keyword(s):  
Turbulence Model ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Inertial Range ◽  
Three Dimensions ◽  
Wave Number ◽  
Two Dimensional ◽  
Dimensionless Constant ◽  
Model Transfer ◽  
Energy Spectrum Function

A simple dynamical argument suggests that the k−3 enstrophy-transfer range in two-dimensional turbulence should be corrected to the form \[ E(k) = C^{\prime} \beta^{\frac{21}{3}}k^{-3}[\ln (k/k_1)]^{-\frac{1}{3}}\quad (k \gg k_1), \] where E(k) is the usual energy-spectrum function, β is the rate of enstrophy transfer per unit mass, C′ is a dimensionless constant, and k1 marks the bottom of the range, where enstrophy is pumped in. Transfer in the energy and enstrophy inertial ranges is computed according to an almost-Markovian Galilean-in variant turbulence model. Transfer in the two-dimensional energy inertial range, \[ E(k) = C\epsilon^{\frac{2}{3}}k^{-\frac{5}{3}}, \] is found to be much less local than in three dimensions, with 60 % of the transfer coming from wave-number triads where the smallest wave-number is less than one-fifth the middle wave-number. The turbulence model yields the estimates C′ = 2·626, C = 6·69 (two dimensions), C = 1·40 (three dimensions).

scholarly journals Scar/WAVE3 contributes to motility and plasticity of lamellipodial dynamics but not invasion in three dimensions

2012 ◽  
Vol 448 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Heather J. Spence ◽  
Paul Timpson ◽  
Hao Ran Tang ◽  
Robert H. Insall ◽  
Laura M. Machesky
Keyword(s):  
Breast Cancer Cells ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Invasion Assay ◽  
Two Dimensional ◽  
Specific Expression ◽  
Camp Receptor ◽  
Syndrome Protein ◽  
Collagen Invasion

The Scar (suppressor of cAMP receptor)/WAVE [WASP (Wiskott–Aldrich syndrome protein) verprolin homologous] complex plays a major role in the motility of cells by activating the Arp2/3 complex, which initiates actin branching and drives protrusions. Mammals have three Scar/WAVE isoforms, which show some tissue-specific expression, but their functions have not been differentiated. In the present study we show that depletion of Scar/WAVE3 in the mammalian breast cancer cells MDA-MB-231 results in larger and less dynamic lamellipodia. Scar/WAVE3-depleted cells move more slowly but more persistently on a two-dimensional matrix and they typically only show one lamellipod. However, Scar/WAVE3 appears to have no role in driving invasiveness in a three-dimensional Matrigel™ invasion assay or a three-dimensional collagen invasion assay, suggesting that lamellipodial persistence as seen in two-dimensions is not crucial in three-dimensional environments.

Toward the Improvement of Education in Mechanics

2005 ◽  
Author(s):  
Hiroshi Tajima
Keyword(s):  
Engineering Education ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Kinematics And Dynamics ◽  
Recent Effort ◽  
Two Dimensional ◽  
The Creation ◽  
Direct Answer

Two catch phrases of my half year lectures of Mechanics, which are given at two Universities, are as follows: “Three dimensions from the beginning”, and “Various methods to derive the equations of motion”. We often do not have enough time to teach kinematics and dynamics from two-dimensional matters first and then proceed to three dimensions. In many cases three-dimensional subjects are considered to be something advanced, or something which two-dimensional methods can be applied to. As a result we often lose chances to teach three-dimensional matters. I think there are few universities that give clear and firm teaching of three dimensional kinematics and dynamics. Many teachers often escape from three-dimensional discussions saying two dimensions are fundamental. I feel that there are very few teachings and discussions in Japan on the methods for deriving the equations of motion. There are many teachers who tell the importance of the equations of motion, but there are few who can discuss various methods to derive them. Discussion and Recognition of various methods not only broaden the application ability but also give clearer understanding in mechanics itself that will connect to the creation of new methodology. My lecture is a direct answer to these points, and my five year experience gives me more confidence in the importance of them. My recent effort is to get more chances to teach it not only within the universities, but also outside of them, getting more sympathetic people. At present I feel that my lecture will surely give some certain effects to the engineering education in mechanics in Japan.

Essential Skills and Information: What Every Teacher and Every Student Should Know about Drawing

2000 ◽  
Author(s):  
Deborah A. Rockman
Keyword(s):  
Language Translation ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Basic Tool ◽  
Actual Form ◽  
Verbal Explanation ◽  
Suitable Tool ◽  
Dimensional Surface

Students often go through the motions of sighting without really understanding what they are doing and why it works. A little understanding of the principles of sighting goes a long way toward encouraging students to use the process to their advantage. . . . Why Use Sighting? . . . Many students have found that they are shining stars when it comes to copying photographs or working from other existing two-dimensional sources. They are often confounded when they discover that drawing from observation of three-dimensional forms does not yield the same strong results, the same degree of accuracy they are accustomed to. It is helpful for both the instructor and the student to understand why this occurs. Drawing or representing a three-dimensional form on a two-dimensional surface requires, in essence, a language translation. The language of two dimensions is different from the language of three dimensions. We must observe the three-dimensional form and translate it into a language that will be effective on a two-dimensional surface, such as a piece of drawing paper. When students draw from an existing two-dimensional source, the translation from 3-D to 2-D has already been made for them. But when they are referring to the actual form, they must make the translation themselves. The process of sighting provides the method for making this translation easily and effectively. A sighting stick is the basic tool for the process of sighting. I recommend using a IO" to I2" length of 1⁄8" dowel. Suitable alternatives include a slender knitting needle, a shish-kebab skewer, or a length of metal cut from a wire clothes hanger. Your sighting stick should be straight. I discourage the use of a drawing pencil as a sighting stick simply because the thickness of the pencil often obscures information when sighting. The more slender the tool, the less it interferes with observing the form or forms being drawn. However, in the absence of a more suitable tool, a pencil will suffice. In presenting sighting principles to a class, it is vital to go beyond a verbal explanation. For students to effectively understand the process, it is strongly recommended that teacher and students walk through the process together, exploring the various ways of applying sighting.

Ferrocene-1,1′-dicarboxylic acid as a building block in supramolecular chemistry: supramolecular structures in one, two and three dimensions

2002 ◽  
Vol 58 (5) ◽  
pp. 786-802 ◽  
Author(s):  
Choudhury M. Zakaria ◽  
George Ferguson ◽  
Alan J. Lough ◽  
Christopher Glidewell
Keyword(s):  
Hydrogen Bonds ◽  
Dicarboxylic Acid ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Supramolecular Structures ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Acid Molecule ◽  
One Dimensional ◽  
Partial Transfer

The supramolecular structures have been determined for nine adducts formed between organic diamines and ferrocene-1,1′-dicarboxylic acid. In the salt-like 1:1 adduct (1) formed with methylamine, the supramolecular structure is one-dimensional, whereas in the 1:1 adducts formed with 1,4-diazabicyclo[2.2.2]octane, (2), and 4,4′-bipyridyl, (4), and in the hydrated 2:1 adduct (3) formed with morpholine, the hard hydrogen bonds form one-dimensional structures, which are expanded to two dimensions by soft C—H...O hydrogen bonds. The hard hydrogen bonds generate two-dimensional structures in the 2:1 adduct (5) formed with octylamine, where the ferrocene component lies across a centre of inversion, in the 1:1 adduct (6) formed with piperidine and in the tetrahydrofuran-solvated 1:1 adduct (7) formed with di(cyclohexyl)amine. In the 2:3 adduct (8) formed by tris-(2-aminoethyl)amine, and in the 2:1 adduct (9) formed with 2-(4′-hydroxyphenyl)ethylamine (tyramine), where Z′ = 1.5 in space group P\bar{1}, the hard hydrogen bonds generate three-dimensional structures. No H transfer from O to N occurs in (4) and only partial transfer of H occurs in (2); in (1), (6) and (7), one H is transferred to N from each acid molecule, and in (3), (5), (8) and (9), two H are transferred from each acid molecule.

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