scholarly journals On the initial geometry of a vacuum cosmological spacetime

2020 ◽  
Vol 37 (8) ◽  
pp. 085017 ◽  
Author(s):  
John Lott
Keyword(s):  
Initial Geometry ◽  
Cosmological Spacetime

scholarly journals Roman Aqueduct Flow Estimation Using Geomatic Measurement

2021 ◽  
Vol 10 (6) ◽  
pp. 360
Author(s):  
Claudio Alimonti ◽  
Valerio Baiocchi ◽  
Giorgia Bonanotte ◽  
Gábor Molnár
Keyword(s):  
High Precision ◽  
Flow Rate ◽  
Point Of View ◽  
Flow Estimation ◽  
Final Goal ◽  
Alternative Methodology ◽  
Orthometric Heights ◽  
The City ◽  
Initial Geometry

The aqueducts built by the ancient Romans are among the most impressive evidence of their engineering skills. The water inside the aqueducts was transported for kilometers, exploiting only the slight but constant differences in altitude throughout the route. To keep the differences in height constant, the aqueducts could proceed underground or aboveground on well-known arched structures that supported lead, ceramic or stone pipes. In order to reconstruct the characteristics of these structures, it is necessary to carry out an accurate survey of the orthometric heights, and therefore the most suitable technology is geometric levelling. In this case, however, it is not applicable, and therefore here we propose an alternative methodology. The final goal of this work was to estimate the flow of some sectors of these aqueducts preserved in the area south of the city of Rome. This has two main purposes: The first is to reconstruct the flow rate of these aqueducts for historical studies; the second is to check how much the orthometric heights have changed over the centuries, in order to reconstruct the movements from a geophysical and geodynamic point of view. The latter analysis will be developed in a following phase of this research. For this purpose, a high-precision geomatic survey was carried out in the area under study, partly retracing a survey already carried out in 1917 whose purpose and methodologies are not known. The area has been affected by a gradual subsidence over centuries, including since 1917. The observed sections of the aqueducts showed average inclinations, slightly lower than the 2 per thousand that is reported in the literature for similar aqueducts. The measurements carried out allowed the flow rate of the two specific aqueducts to be estimated more accurately, both as they were originally and in the presence of deposits that have accumulated during the years of use of the aqueducts. The reconstruction of the initial geometry will later be used as a reference to estimate how much the geodynamic deformations of the area have deformed the aqueducts themselves.

Structural stability of CmTin microclusters and nanoparticles: Molecular–dynamics simulations

2005 ◽  
Vol 1 (4) ◽  
pp. 204-209
Author(s):  
O.B. Malcıoğlu ◽  
Ş. Erkoç
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Binary Systems ◽  
Minimum Energy ◽  
Potential Energy Function ◽  
Md Simulations ◽  
Atomic Interactions ◽  
Dynamics Simulations ◽  
Three Body ◽  
Initial Geometry

The minimum energy structures of CmTin microclusters and nanoparticles have been investigated theoretically by performing molecular–dynamics (MD) simulations. Selected crystalline and completely random initial geometries are considered. The potential energy function (PEF) used in the calculations includes two– and three–body atomic interactions for C-Ti binary systems. Molecular–dynamics simulations have been performed at 1 K and 300 K. It has been found that initial geometry has a very strong influence on relaxed geometry

Adaptive-Curvature Structures with Auxetic Materials

2018 ◽  
Vol 1149 ◽  
pp. 53-63
Author(s):  
Roberto Naboni ◽  
Stefano Sartori ◽  
Lorenzo Mirante
Keyword(s):  
Large Scale ◽  
Morphological Features ◽  
Geometrical Parameters ◽  
Computational Tools ◽  
Auxetic Materials ◽  
Initial Geometry ◽  
Tools And Methods

Advancements in computational tools are offering designers the possibility to change their relationship with materials and establishing new synergies between matter, form and behaviour. This work explores this paradigm by introducing the use of auxetic metamaterials, specifically engineered to obtain properties beyond those found in nature, to generate structures with adaptive curvature obtained from planar construction elements. It is discussed how through programming an initial geometry with the strategic negotiation of several geometrical parameters it is possible to control finely the structural and morphological features of a structure. The paper presents approach, tools and methods for designing auxetics for large scale applications, and use them to create heterogeneous active-bending structures.

scholarly journals The role of initial geometry in experimental models of wound closing

2018 ◽  
Vol 179 ◽  
pp. 221-226 ◽  
Author(s):  
Wang Jin ◽  
Kai-Yin Lo ◽  
Shih–En Chou ◽  
Scott W. McCue ◽  
Matthew J. Simpson
Keyword(s):  
Experimental Models ◽  
Initial Geometry

scholarly journals ARCHITECTURAL DESIGN METHODS OF RENOVATION OF INTERIORS OF HISTORICAL BUILDINGS

2020 ◽  
pp. 272-280
Author(s):  
E. Turikova ◽  
◽  
O. Nedoshytko ◽  
A. Akopova ◽  
◽  
...  
Keyword(s):  
Visual Field ◽  
Architectural Design ◽  
Human Factor ◽  
Structural Basis ◽  
Historical Buildings ◽  
Historical Building ◽  
Student Work ◽  
Interior Spaces ◽  
Light Color ◽  
Initial Geometry

In this article specific examples of historical interiors are identified and characterized, environment-forming factors determining the individuality of the historic interior and its renovation strategy are highlighted; shows the methods of renovation andreprofiling of historical interiors, their selection and testing in real environmental conditions.The historical buildings that make up the golden fund for the development of old cities often carry a bunch of contradictions: their interiors do not alwaysmeet today's requirements for the geometry of interior spaces, their hygiene, lighting, acoustics; the structural basis does not allow to increase the load; they are not designed for new functions, modes of operation, flows of people, etc.; the existing aesthetic system contradicts modern materials and stylistic priorities. Incorrect adaptation of historical interiors to a foreign function leads to irreplaceable cultural and artistic losses. Therefore, it is relevant to identify techniques for the renovation of historical interiors, architectural and design tools to ensure consistent interaction of the historical foundation and modern equipment.The study allowed to clarify the concept of “interior of a historic building”; to reveal the factors that determine the design approaches to the renovation of the interior: initial geometry, hue-color certainty and potential, artistic and stylistic integrity, scenographic potential, sanitary-hygienic and ergonomic, safety, human factor, compositional reality and potential. The identified factors made it possible to formulate the tasks and means of renovating aspecific historical interior. The methods of renovation are: the introduction of a contrasting accent; creation of alternative environmental and stylistic scenarios, points and perspectives of perception; use of environmentalinstallations from equipment; the formation of a single visual field of the interior and exterior through the use of font, elements of historical style.The article “Architectural and design techniques for renovating the interiors of historical buildings” clarifies the concept of “interior of a historical building”. The features of such interiors were identified and characterized, environment-forming factors determining the individuality of the historical interior and the strategy for its renovation, as well as design approaches to interior renovation: initial geometry, light-color certainty and potential, artistic and stylistic integrity, scenographic potential, sanitary-hygienic and ergonomic, were identified, security, human factor, compositional givenness and potential. The methods of renovation and reprofiling of historical interiors are shown, they are selected and tested in real environmental conditions. The identified factors made it possible to formulate the tasks and means of renovating aspecific historical interior. The methods of renovation are: the introduction of a contrasting accent; creation of alternative environmental and stylistic scenarios, points and perspectives of perception; use of environmental installations from equipment; the formation of a single visual field of the interior and exterior through the use of font, elements of historical style. The article is illustrated with graphic materials from the course student work (Art. Yulia Shtyrbu).

On the influence of initial geometry on the evolution of fluid filaments

2015 ◽  
Vol 27 (9) ◽  
pp. 092104 ◽  
Author(s):  
K. Mahady ◽  
S. Afkhami ◽  
L. Kondic
Keyword(s):  
Initial Geometry

Development of an Optimization Framework for Parameter Identification and Shape Optimization Problems in Engineering

2011 ◽  
Vol 1 (1) ◽  
pp. 57-79 ◽  
Author(s):  
A. Andrade-Campos
Keyword(s):  
Inverse Problems ◽  
Shape Optimization ◽  
Parameter Identification ◽  
Optimization Problems ◽  
Optimization Methods ◽  
Optimum Shape ◽  
Optimization Framework ◽  
Search Optimization ◽  
Initial Geometry

The use of optimization methods in engineering is increasing. Process and product optimization, inverse problems, shape optimization, and topology optimization are frequent problems both in industry and science communities. In this paper, an optimization framework for engineering inverse problems such as the parameter identification and the shape optimization problems is presented. It inherits the large experience gain in such problems by the SiDoLo code and adds the latest developments in direct search optimization algorithms. User subroutines in Sdl allow the program to be customized for particular applications. Several applications in parameter identification and shape optimization topics using Sdl Lab are presented. The use of commercial and non-commercial (in-house) Finite Element Method codes to evaluate the objective function can be achieved using the interfaces pre-developed in Sdl Lab. The shape optimization problem of the determination of the initial geometry of a blank on a deep drawing square cup problem is analysed and discussed. The main goal of this problem is to determine the optimum shape of the initial blank in order to save latter trimming operations and costs.

scholarly journals Multistable Morphing Mechanisms of Nonlinear Springs

2019 ◽  
Vol 11 (5) ◽  
Author(s):  
Chrysoula Aza ◽  
Alberto Pirrera ◽  
Mark Schenk
Keyword(s):  
Design Space ◽  
Large Deformations ◽  
Compliant Mechanisms ◽  
Helical Structures ◽  
Nonlinear Springs ◽  
Structural Assembly ◽  
Stiffness Characteristics ◽  
Nonlinear Components ◽  
Type Of Behavior ◽  
Initial Geometry

Compliant mechanisms find use in numerous applications in both microscale and macroscale devices. Most of the current compliant mechanisms base their behavior on beam flexures. Their range of motion is thus limited by the stresses developed upon deflection. Conversely, the proposed mechanism relies on elastically nonlinear components to achieve large deformations. These nonlinear elements are composite morphing double-helical structures that are able to extend and coil like springs, yet, with nonlinear stiffness characteristics. A mechanism consisting of such structures, assembled in a simple truss configuration, is explored. A variety of behaviors is unveiled that could be exploited to expand the design space of current compliant mechanisms. The type of behavior is found to depend on the initial geometry of the structural assembly, the lay-up, and other characteristics specific of the composite components.

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