scholarly journals Visualizing surface formation of semi-regular polyhedra of Archimedes

2020 ◽  
Vol 16 (4) ◽  
pp. 279-289
Author(s):  
Viktoryna A. Romanova
Keyword(s):  
Geometric Parameters ◽  
Common Method ◽  
Dihedral Angles ◽  
Functional Language ◽  
Surface Formation ◽  
Monitor Screen ◽  
Regular Polyhedra ◽  
Electronic Model ◽  
Kinematic Method ◽  
Special Programs

The most common method of forming semi-control polyhedra consists in cutting off angles and ribs of regular polyhedra by planes. The aim of the work - to consider the automated formation of a number of surfaces of semi-regular Archimedean polyhedra based on the dodecahedron. These include the truncated dodecahedron, the icosododecahedron, the romboicosododecahedron and the truncated icosododecahedron. The formation of surfaces is carried out by the kinematic method in AutoCAD using programs compiled in the AutoLISP language. Methods. The methodology for the formation of these polyhedra provides for truncation of the angles and edges of the dodecahedron. This requires the calculation of a number of geometric parameters of these polyhedra and dodecahedron, such as the value of the truncation of the dodecahedron edges, the size of the edges of truncated polyhedra, the centers of faces, dihedral angles, etc. In order to generate these surfaces, a frame is constructed because the frame lines are used as guides to form surfaces in a kinematic way. The electronic model of each polyhedron is constructed as a set of compartments of surfaces of all its faces, and each compartment is assigned to a certain layer of the drawing. The frame and electronic model of the polyhedra under study are formed by means of user programs composed in the functional language AutoLISP. The process of forming surfaces of selected polyhedra in the AutoCAD environment is provided by special programs that are also compiled in the AutoLISP language. Results. Software was created to demonstrate the process of formation of a number of Archimedes polyhedra on the monitor screen.

scholarly journals Vizualizing of semi-regular polyhedrons in AutoCAD environment

2019 ◽  
Vol 15 (6) ◽  
pp. 449-457
Author(s):  
Viktoryna A. Romanova
Keyword(s):  
Programming Language ◽  
Functional Programming ◽  
Dynamic Mode ◽  
Structural Shape ◽  
Monitor Screen ◽  
Research Software ◽  
Truncated Octahedron ◽  
Regular Polyhedra ◽  
Electronic Model ◽  
Kinematic Method

The paper examines the automated formation by the kinematic method of the surfaces of Archimedes' semi-regular polyhedra of three forms: truncated tetrahedron, truncated octahedron and truncated icosahedron. To solve this problem, AutoCAD and the built-in programming language AutoLISP were used. Each of these five semi-regular polyhedra of Archimedes has faces of two kinds. In this regard, the surface of a separate polyhedron is considered to consist of two structural forms. Each structural shape is formed in the AutoCAD environment from the compartments of the surfaces of the faces of the polyhedron of the same type, and each compartment is assigned to a specific layer of the drawing. The formation of constructive forms is provided by user-defined functions developed in the functional programming language AutoLISP. User-defined functions not only form images of surfaces, but also perform all the necessary calculations. The electronic model of each polyhedron is formed by the union of its structural forms. A block is formed from it. The surface formation of each polyhedron performs user-defined functions that provide “freezing” of drawing layers intended for surface compartments, insertion of a block with an electronic model of the polyhedron, and sequential “defrosting” of drawing layers. When there is a “thawing" of the layers of the drawing, the process of forming a polyhedron is shown on the monitor screen. As a result of research software that includes userdefined functions for the formation of an electronic model of selected polyhedrons and visualization of the process of formation of their surfaces in a dynamic mode was created.

Analysis of geometric parameters and packing considerations for triphenylboroxine derivatives, with tris(pentafluorophenyl)boroxine as an example

2012 ◽  
Vol 68 (5) ◽  
pp. o204-o208 ◽  
Author(s):  
Jan Tillmann ◽  
Hans-Wolfram Lerner ◽  
Tanja Sinke ◽  
Michael Bolte
Keyword(s):  
Dihedral Angle ◽  
Title Compound ◽  
Interplanar Spacing ◽  
Geometric Parameters ◽  
Dihedral Angles ◽  
Rotation Axes ◽  
Benzene Rings ◽  
Similarities And Differences

Molecules of the title compound [systematic name: 2,4,6-(pentafluorophenyl)-1,3,5,2,4,6-trioxatriborinane], C18B3F15O3, are located on crystallographic twofold rotation axes which run through the boroxine and one of the pentafluorophenyl rings. The boroxine ring (r.m.s. deviation = 0.027 Å) and the pentafluorophenyl rings (r.m.s. deviations = 0.004 and 0.001 Å) are essentially planar. The dihedral angles between the boroxine and the two symmetry-independent benzene rings are 8.64 (10) and 8.74 (12)°. The two benzene rings are mutually coparallel [dihedral angle = 0.80 (11)°]. The packing shows planes of molecules parallel to (\overline{2}01), with an interplanar spacing of 2.99 Å. Within these planes, all the molecules are oriented in the same direction, whereas in neighbouring planes the direction is inverted. Short B...F contacts of 3.040 (2) and 3.1624 (12) Å occur between planes. The geometric parameters of the boroxine ring in the title compound agree well with those of comparable boroxine structures, while the packing reveals some striking similarities and differences.

XII.—Isohedral and Isogonal Generalizations of the Regular Polyhedra

1933 ◽  
Vol 52 ◽  
pp. 251-263 ◽  
Author(s):  
D. M. Y. Sommerville
Keyword(s):  
Dihedral Angles ◽  
Regular Polyhedra

0.1. In Max Brückner's discussion of isohedral (gleichflächig) and isogonal (gleicheckig) polyhedra (Vielecke und Vielflache, pp. 140 ff.) two faces of a polyhedron are defined to be equal when they are either directly or inversely congruent, and the dihedral angles at corresponding edges are equal; two vertices are equal when the spherical polygons, which they form on unit spheres with centres at the vertices, are either directly or inversely congruent, and the lengths of corresponding edges are equal. With these definitions he shows that all possible isogonal polyhedra are obtained by truncating the corners and edges of the regular n-sided prism, the octahedron and hexahedron, and the icosahedron and dodecahedron, in a manner similar to that in which the semi-regular polyhedra are obtained from the regular polyhedra. The semi-regular or Archimedean bodies are indeed just special varieties of the more general isogonal polyhedra. The isohedral polyhedra are the polar reciprocals of the isogonal polyhedra, and are obtained from the regular double-pyramid and the regular polyhedra by the reciprocal constructions, “pointing” the faces and edges.

scholarly journals Formation surfaces of Monge by the kinematic method in AutoCAD environment

2019 ◽  
Vol 15 (2) ◽  
pp. 106-116
Author(s):  
Viktoryna A Romanova
Keyword(s):  
Tangent Plane ◽  
Sine Wave ◽  
Circular Cone ◽  
Dynamic Mode ◽  
Developable Surface ◽  
Monitor Screen ◽  
Straight Line ◽  
Kinematic Method ◽  
Conical Surfaces

Aims of research. Studying the possibility of forming Monge carved surfaces, defined by the method of their formation, creating an algorithm and program in the AutoLISP language to demonstrate the formation of surfaces in the AutoCAD environment in a dynamic mode. Methods. Monge carved surfaces are formed by a flat curve, located in the tangent plane to the fixed guide of the developable surface, when the plane and the curve roll along the guide surface without sliding. The described method of formation of these surfaces allows to perform their formation by the kinematic method in the AutoCAD environment using AutoLISP software. The article describes the construction of the Monge surfaces using cylindrical and conical surfaces as guides. A straight line and a sine wave are used as the forming lines. Results. An algorithm and a program in the AutoLISP language were created to form sets of compartments of several Monge surfaces and to visualize the formation of these surfaces in a dynamic mode by sequentially displaying the compartments on the monitor screen. The mini-film about formation of Monge surface by rolling a plane with a straight line along a circular cone is created. In the mini-film the drawings received by transformation of drawings of the AutoCAD environment are used.

Structural and Technology Support Quality Improvement of Gear Coupling

2013 ◽  
Vol 371 ◽  
pp. 3-7
Author(s):  
Aleksandr Mikhaylov ◽  
Roman Grubka ◽  
Aleksey Lahin ◽  
Alexander Nedashkovskiy ◽  
Ahmed Guitouni
Keyword(s):  
Mechanical Properties ◽  
Quality Improvement ◽  
Mechanical Treatment ◽  
Design Procedure ◽  
Treatment Method ◽  
Geometric Parameters ◽  
Technology Support ◽  
Kinematic Method ◽  
Thermo Mechanical Treatment

In this work the question of sharing use a thermo-mechanical treatment method and forming spatial tool based on a kinematic method researches gearings, is considered. Also, the method of thermo mechanical treatment a gear couplings teeth, with the receiving a spatial teeth geometry and ensuring required physical- mechanical properties of them, is presented. For implementation of this method, the scheme of the device and the special tool is developed, which allows to fair blanking of spatially modified teeth. The design procedure a teeth tool’s geometric parameters of the line addendum modification are offered.

scholarly journals Mechanisms for surface formation of accurate bimetallic casting at technological stages of its production

2020 ◽  
pp. 214-221
Author(s):  
Сергей Геннадьевич Жилин ◽  
Олег Николаевич Комаров ◽  
Нина Анатольевна Богданова
Keyword(s):  
High Accuracy ◽  
Steel Frame ◽  
Common Method ◽  
Elastic Response ◽  
Surface Formation ◽  
Plastic Materials

Решение задач, связанных с физической трансформаций материала, сопровождающей этапы получения биметаллических отливок повышенной точности, актуально и востребовано в машиностроении. Распространенный метод получения таких изделий - литье по выплавляемым моделям. Проблемными стадиями являются прессование воскообразного слоя удаляемой модели и формирование поверхности из пластических материалов на стальном каркасе. Упругий отклик, возникающий вследствие теплофизических процессов формоизменения, определяет необходимость устранения напряжения в материалах. Solving problems associated with the physical transformations of the material that accompanies the stages of obtaining bimetallic castings of high accuracy is relevant and in demand in engineering. A common method for producing such products is lost wax casting. The problematic stages are the pressing of the waxy layer of the removed model and the formation of the surface from plastic materials on a steel frame. The elastic response arising from thermophysical processes of shaping determines the need to eliminate stress in materials.

5-(4′-Methylbiphenyl-2-yl)-2-triphenylmethyl-2H-tetrazole

2007 ◽  
Vol 63 (11) ◽  
pp. o4410-o4410 ◽  
Author(s):  
Guo-Xi Wang ◽  
Heng-Yun Ye
Keyword(s):  
Benzene Ring ◽  
Dihedral Angle ◽  
Title Compound ◽  
Geometric Parameters ◽  
Tetrazole Ring ◽  
Dihedral Angles ◽  
Aromatic Rings ◽  
Compound C ◽  
Phenyl Rings

The title compound, C33H26N4, was synthesized in two steps from 2-phenylbenzonitrile. Geometric parameters are in the usual ranges. The tetrazole ring encloses dihedral angles of 45.76 (9), 71.44 (8) and 72.38 (6)° with the three phenyl rings of the triphenylmethyl group. The dihedral angle between the tetrazole ring and the benzene ring directly attached to it is 49.13 (8)° and the dihedral angle between the aromatic rings of the biphenyl group is 54.29 (8)°.

Lectin-Induced RBC Agglutination: Chemical vs. Cryofixation

1980 ◽  
Vol 38 ◽  
pp. 664-665
Author(s):  
Dean A. Handley ◽  
Lanping A. Sung ◽  
Shu Chien
Keyword(s):  
Lectin Binding ◽  
Freeze Substitution ◽  
Electrostatic Charge ◽  
Geometric Parameters ◽  
Comparative Approach ◽  
Chemical Fixation ◽  
Cell Surfaces ◽  
Minimal Cell ◽  
Membrane Stiffness ◽  
Cell Contour

RBC agglutination by lectins represents an interactive balance between the attractive (bridging) force due to lectin binding on cell surfaces and disaggregating forces, such as membrane stiffness and electrostatic charge repulsion (1). During agglutination, critical geometric parameters of cell contour and intercellular distance reflect the magnitude of these interactive forces and the size of the bridging macromolecule (2). Valid ultrastructural measurements of these geometric parameters from agglutinated RBC's require preservation with minimal cell distortion. As chemical fixation may adversely influence RBC geometric properties (3), we used chemical fixation and cryofixation (rapid freezing followed by freeze-substitution) as a comparative approach to examine these parameters from RBC agglutinated with Ulex I lectin.

Writing Funding Proposals for Speech-Language Staff Development Projects

1982 ◽  
Vol 13 (3) ◽  
pp. 163-171
Author(s):  
Carol A. Esterreicher ◽  
Ralph J. Haws
Keyword(s):  
Staff Development ◽  
Development Project ◽  
Project Manager ◽  
State Funding ◽  
Service Needs ◽  
School Environments ◽  
Speech Language Pathologists ◽  
Service Programs ◽  
Speech Language Pathologist ◽  
Special Programs

Speech-language pathologists providing services to handicapped children have pointed out that special education in-service programs in their public school environments frequently do not satisfy the need for updating specific diagnostic and therapy skills. It is the purpose of this article to alert speech-language pathologists to PL 94-142 regulations providing for personnel development, and to inform them of ways to seek state funding for projects to meet their specialized in-service needs. Although a brief project summary is included, primarily the article outlines a procedure whereby the project manager (a speech-language pathologist) and the project director (an administrator in charge of special programs in a Utah school district) collaborated successfully to propose a staff development project which was funded.

Assessing Functional Language in School-Aged Children Using Language Sample Analysis

2020 ◽  
Vol 5 (3) ◽  
pp. 622-636
Author(s):  
John Heilmann ◽  
Alexander Tucci ◽  
Elena Plante ◽  
Jon F. Miller
Keyword(s):  
Computer Hardware ◽  
School Age Children ◽  
Functional Language ◽  
School Age ◽  
Clinical Use ◽  
Sample Analysis ◽  
Validity And Reliability ◽  
Language Sample Analysis ◽  
Accuracy And Repeatability ◽  
Language Sample

Purpose The goal of this clinical focus article is to illustrate how speech-language pathologists can document the functional language of school-age children using language sample analysis (LSA). Advances in computer hardware and software are detailed making LSA more accessible for clinical use. Method This clinical focus article illustrates how documenting school-age student's communicative functioning is central to comprehensive assessment and how using LSA can meet multiple needs within this assessment. LSA can document students' meaningful participation in their daily life through assessment of their language used during everyday tasks. The many advances in computerized LSA are detailed with a primary focus on the Systematic Analysis of Language Transcripts (Miller & Iglesias, 2019). The LSA process is reviewed detailing the steps necessary for computers to calculate word, morpheme, utterance, and discourse features of functional language. Conclusion These advances in computer technology and software development have made LSA clinically feasible through standardized elicitation and transcription methods that improve accuracy and repeatability. In addition to improved accuracy, validity, and reliability of LSA, databases of typical speakers to document status and automated report writing more than justify the time required. Software now provides many innovations that make LSA simpler and more accessible for clinical use. Supplemental Material https://doi.org/10.23641/asha.12456719

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