scholarly journals The pencil of the 4th and 3rd order surfaces obtained as a harmonic equivalent of the pencil of quadrics through a 4th order space curve of the 1st category

2012 ◽  
Vol 10 (2) ◽  
pp. 193-207 ◽  
Author(s):  
Gordana Djukanovic ◽  
Marija Obradovic
Keyword(s):  
Cross Sections ◽  
Spatial Model ◽  
Spatial Models ◽  
Space Curve ◽  
Parabolic Cylinder ◽  
Triaxial Ellipsoid ◽  
Architectural Practice ◽  
Ordered Space ◽  
Pass Through ◽  
Frontal Projection

This paper shows the process of inverting the 4th ordered space curve of the first category with a self-intersecting point (with two planes of symmetry) and determining its harmonic equivalent. There are harmonic equivalents for five groups of surfaces obtained through the 4th order space curve of the 1st category. Mapping was done through a system of circular cross-sections. Both classical and relativistic geometry interpretations are presented. We also designed spatial models - a spatial model of the pencil of quadrics and a spatial model of the pencil of equivalent quadrics. Besides the boundary surfaces, one surface of the 3rd order, which is an equivalent to a triaxial ellipsoid, passes through this pencil of surface of the 4th order. The center of inversion is located on the contour of the ellipsoid. The parabolic cylinder is mapped into its equivalent, by mapping the contour parabola of the cylinder, in the frontal projection, in relation to the center and the sphere of inversion into a contour curve of the 4th order surface. The generating lines of the parabolic cylinder, which are in a projecting position and pass through the antipode, are mapped into circles (also in a projecting position) whose diameters are from the center of inversion to the contour line. The application of the 4th order surfaces in architectural practice is also presented.

Introduction

2018 ◽  
Author(s):  
Justin Buchler
Keyword(s):  
Spatial Model ◽  
Spatial Models ◽  
Spatial Theory ◽  
Roll Call ◽  
Policy Space ◽  
Policy Decisions ◽  
Roll Call Voting ◽  
Legislative Session ◽  
History Of ◽  
Conventional Models

Spatial theory is divided between models of elections and models of roll call voting, neither of which alone can explain congressional polarization. This chapter discusses the history of spatial theory, why it is important to link the two strands of spatial models, and the value of reversing the order of conventional models. Conventional models place an election before policy decisions are made. This chapter proposes a unified spatial model of Congress in which the conventional order is reversed. First, there is a legislative session, then an election in which voters respond retrospectively, not to the locations candidates claim to hold, but to the bundles of roll call votes that incumbents cast to incrementally adopt their locations in the policy space. Such a model is best suited to explaining three puzzles: why do legislators adopt extreme positions, how do they win, and what role do parties play in the process?

scholarly journals The tourism space of Barlinek in the context of spatial models

Turyzm ◽  
2018 ◽  
Vol 28 (2) ◽  
pp. 31-40
Author(s):  
Bartłomiej Łuć
Keyword(s):  
Spatial Model ◽  
Swot Analysis ◽  
Spatial Models ◽  
Tourism Development ◽  
Field Studies ◽  
Tourism Attractions

This article describes the tourism space of Barlinek in the context of a spatial model. On the basis of field studies and analyses of tourism attractions and elements of tourism development, the author has compared and adapted the models developed by S. Liszewski (1995) and B. Włodarczyk (2011). Moreover the author has developed an extended SWOT analysis of Barlinek’s tourism space.

Learning Hyperparameters in Efficient Spatial Model by Robotic Sensors

2019 ◽  
Author(s):  
Jinho Jeong ◽  
Soo Jeon ◽  
Jongeun Choi
Keyword(s):  
Mobile Robots ◽  
Learning Strategies ◽  
Spatial Model ◽  
Markov Random Fields ◽  
Spatial Models ◽  
Future Research ◽  
Gaussian Markov Random Fields ◽  
New Class ◽  
Future Research Directions ◽  
Proximity Graph

Abstract Recently, a new class of spatial models over a continuum domain that builds on hidden Gaussian Markov Random Fields (GMRFs) was proposed for resource-constrained networked mobile robots dealing with non-stationary physical processes. The hidden GMRF was realized with respect to a proximity graph over a surveillance region. In this paper, we investigate learning strategies based on the maximum likelihood (ML) and the maximum a posteriori (MAP) estimators to find the locational generating points for the spatial model so that mobile robots can efficiently make the prediction. Some promising simulation results and future research directions are discussed.

Electron mobilities in alkanes through the liquid and critical regions

1977 ◽  
Vol 55 (11) ◽  
pp. 2264-2277 ◽  
Author(s):  
Jean-Pol Dodelet ◽  
Gordon R. Freeman
Keyword(s):  
Electric Field ◽  
Field Dependence ◽  
Cross Sections ◽  
Critical Phenomenon ◽  
Critical Density ◽  
Molecular Shape ◽  
Localized States ◽  
Liquid Density ◽  
Low Energies ◽  
Pass Through

Three properties of electrons in liquids are governed by scattering at low energies and show similar dependence upon liquid density and molecular shape. They are the mobility, the dependence of the mobility upon electric field strength, and the penetration range of low energy (<10 eV) electrons. The scattering cross sections of hydrocarbons in the liquid phase (near or below the normal boiling point) are smaller when the molecules are more sphere-like. The degree of sphericity of the molecules in the present series decreases in the order 2,2-dimethylpropane (DMPr) > 2,2-dimethylbutane (DMB) > cyclopentane (cP) > n-pentane (nP).Electron mobilities in DMPr and DMB measured as functions of the liquid density pass through maxima similar to those observed earlier in argon and xenon. The magnitudes of the maxima decrease in the order Xe > Ar > DMPr > DMB. The maxima occur at densities approximately double the critical density dc. There is a small maximum for electrons in cP, but none for those in nP.The mobilities in the supercritical gases are similar for the four compounds. The Arrhenius temperature coefficients are all 7–10 kcal/mol (0.3–0.4 eV/electron) for temperatures and densities near the critical values. This implies that electrons form localized states in the gases. The extent of localization in supercritical DMPr appears to be greater than that in the normal liquid. The localization is not the critical phenomenon predicted by Lekner.The mobility in liquid DMPr decreases at high electric field strengths. The magnitude of the field dependence changes with the liquid density and passes through a maximum similar to that of the mobility itself. The field dependence in liquid DMB is smaller than that in DMPr, but it also passes through a maximum at a density about double dc.Equations are given that describe the mobility in nP at all temperatures from the triple point through to the supercritical gas. The electrons reside mainly in localized states over the entire temperature range, but transport occurs mainly in extended states to which the electrons are thermally excited.The penetration range parameter bGP of secondary electrons in these liquids is normalized for comparison by multiplying by the liquid density d. The values of bGPd plotted against d form curves similar in shape to the μ against d curves, but the relative variations in bGPd are much smaller.

Size Effect of Ion Translocation through Nanopore by Molecular Dynamics

2014 ◽  
Vol 692 ◽  
pp. 420-423 ◽  
Author(s):  
Itsuo Hanasaki ◽  
Yoshihiro Kuzuya ◽  
Satoyuki Kawano
Keyword(s):  
Molecular Dynamics ◽  
Size Effect ◽  
Cross Sections ◽  
Finite Size ◽  
Effective Size ◽  
Finite Size Effect ◽  
Channel Diameter ◽  
Sequencing Technologies ◽  
Ion Translocation ◽  
Pass Through

While the flow rates (in unit of particles/s) of the ions in aqueous solution depend on the cross sections of the channels they pass through, the flux (in unit of particles/(m2s)) is usually independent of them. However, if the diameter of the channel becomes extremely small and comparable to the effective size of the ions, there can be the dependence of the flux on the channel diameter. The finite size effect of solute ions through such small channel is relevant to the physical process of other nanofluidic technologies such as the DNA translocation through nanopore for the sequencing technologies. In this study, we examine the flow of K+ and Cl- ions in water through nanopores made of graphene structure by molecular dynamics method. The results show that there is a transition of zero to nonzero flux when the pore diameter is around the effective size of the ions. Furthermore, there is a dependence of the flux on the nanopore diameter around this regime.

scholarly journals THE ULTRASTRUCTURE OF THE Z DISC IN SKELETAL MUSCLE

1962 ◽  
Vol 13 (2) ◽  
pp. 323-335 ◽  
Author(s):  
G. G. Knappeis ◽  
F. Carlsen
Keyword(s):  
Skeletal Muscle ◽  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Cross Sections ◽  
Electron Microscopic ◽  
Structural Arrangement ◽  
Special Regard ◽  
Pass Through

This electron microscopic study deals with the structure of the Z disc of frog's skeletal muscle, with special regard to the I filaments—whether they pass through the Z disc or terminate at it. In most longitudinal sections the I filaments terminate as rod-like projections on either side of the Z disc, one I filament on one side lying between two I filaments on the opposite side. This indicates that the I filaments are not continuous through the Z disc. The rod-like projections are often seen to consist of filaments (denoted as Z filaments) which meet at an angle. In cross-sections through the Z region the I filaments and Z filaments form tetragonal patterns. The I filaments are situated in the corners of the squares; the oblique Z filaments form the sides of squares. The tetragonal pattern formed by the Z filaments is rotated 45 degrees with respect to the tetragons formed by the I filaments on both sides of Z. This structural arrangement is interpreted to indicate that each I filament on one side of the Z disc faces the center of the space between four I filaments on the opposite side of Z and that the interconnection is formed by four Z filaments.

scholarly journals Modeling land use impacts on spatial distribution of floating plastic litter in surface water of Southeast Asian archipelago

2021 ◽  
Author(s):  
Andri Wibowo
Keyword(s):  
Land Use ◽  
Spatial Distribution ◽  
Surface Water ◽  
Population Density ◽  
Southeast Asia ◽  
Spatial Model ◽  
Spatial Models ◽  
Southeast Asian ◽  
Land Use Impacts

AbstractPlastics are present in many ecosystems including floating in surface water of remote archipelago and this can lead to the increase in plastic litter density. Whereas the spatial model of plastic litter density related to the population inhabits isolated archipelago is still limited. And what are the underlying factors driving the presence of plastic litter is also poorly understood. This study is trying to find the answers of those questions. The study was implemented in Thousand Island archipelago located in North of Java Island, one of populated islands in Southeast Asia. The studied surface water covers an area of 10000 Ha and consists of 10 islands with 3 islands are occupied by settlements and the remaining islands are occupied by vegetation. This study has recorded 3 types of floating macro-litter from water that consist of PET, HDPE, and LDPE litter. The plastic litter was observed concentrated in the east sides of archipelago where the populated islands were located. The spatial models show LDPE litter was distributed in the vast areas in comparison to PET and HDPE litter. Beside land use variables, the model has confirmed that the population density was the main underlying factors contribute to the plastic litter density in Thousand Island archipelago. The model can be applied to estimate PET (AIC = −0.53060) and HDPE (AIC = 18.28828) litter density. While LDPE litter density was influenced by population (AIC = 22.60201) rather than population density factors.

scholarly journals Spatial regression and geostatistics discourse with empirical application to precipitation data in Nigeria

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Oluyemi A. Okunlola ◽  
Mohannad Alobid ◽  
Olusanya E. Olubusoye ◽  
Kayode Ayinde ◽  
Adewale F. Lukman ◽  
...  
Keyword(s):  
Spatial Model ◽  
Spatial Regression ◽  
Spatial Models ◽  
Cold Spot ◽  
Precipitation Data ◽  
Error Structure ◽  
Robust Approach ◽  
Spatial Linear Model ◽  
Spatial Autoregressive ◽  
Definition Of

AbstractIn this study, we propose a robust approach to handling geo-referenced data and discuss its statistical analysis. The linear regression model has been found inappropriate in this type of study. This motivates us to redefine its error structure to incorporate the spatial components inherent in the data into the model. Therefore, four spatial models emanated from the re-definition of the error structure. We fitted the spatial and the non-spatial linear model to the precipitation data and compared their results. All the spatial models outperformed the non-spatial model. The Spatial Autoregressive with additional autoregressive error structure (SARAR) model is the most adequate among the spatial models. Furthermore, we identified the hot and cold spot locations of precipitation and their spatial distribution in the study area.

scholarly journals Floating Ice Transport Conditions at the Cross-Sections Between Pier Columns in Open Ice-Water Two-Phase Flow Canals

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1813
Author(s):  
Xiangpeng Mu ◽  
Juan Bao ◽  
Yunfei Chen
Keyword(s):  
Cross Sections ◽  
Empirical Equation ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Two Phase ◽  
Hydraulic Conditions ◽  
Ice Conditions ◽  
The Cross ◽  
Pass Through ◽  
Ice Water

Floating ice is easy to jam at the cross-sections contracted by bridge pier, gate pier, etc., in ice-water two-phase flow canals. To solve the problem, the critical hydraulic conditions of floating ice transport at the cross-sections between pier columns were explored in this study. Based on the generalized physical model of the cross-sections between pier columns of water transfer canals, the movement and transport characteristics of floating ice in front of the pier columns were studied under different hydraulic conditions and ice conditions, and the critical hydraulic conditions necessary for floating ice to pass through the cross-sections between pier columns were analyzed. Moreover, dimensional analysis and regression analysis were carried out in order to establish an empirical equation for calculating the critical water flow Fr (Froude number) for the floating ice to be transported through the cross-sections between pier columns, thus providing a basis for the ice jam risk assessment and hydraulic regulation of ice-water two-phase flow canals, as well as control of the emergent ice drainage of canals during freezing periods.

scholarly journals The Tritangent Circles of a Circular Quartic Curve

1932 ◽  
Vol 3 (1) ◽  
pp. 46-52
Author(s):  
H. W. Richmond
Keyword(s):  
Fixed Points ◽  
Space Curve ◽  
Cubic Surface ◽  
Quartic Curve ◽  
Family Of Curves ◽  
The Family ◽  
The Subject ◽  
Simple Notation ◽  
Pass Through

§1. In a recent paper with this title Prof. W. P. Milne has discussed the properties of the conics which pass through two fixed points of a plane quartic curve and touch the curve at three other points. In dealing with a numerous family of curves such as this it is very desirable to have a scheme of marks or labels to distinguish the different members of the family; Hesse's notation for the double tangents of a C4 illustrates this. By using another line of approach to the subject, by projecting the curve of intersection of a quadric and a cubic surface from a point at which (under exceptional circumstances) the surfaces touch, I find that a fairly simple notation for the 64 conics, in harmony with that for the bitangents, can be obtained. This paper, let it be said, from start to finish is no more than an adaptation of results known for the sextic space-curve referred to; it will be sufficient therefore to state results with short explanations.

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