Vulnerability Assessment of Damaged Classical Multidrum Columns

2016 ◽  
pp. 235-253
Author(s):  
Michalis Fragiadakis ◽  
Ioannis Stefanou ◽  
Ioannis N. Psycharis
Keyword(s):  
Seismic Risk ◽  
Limit State ◽  
Three Dimensional ◽  
The Other ◽  
Performance Criteria ◽  
Structural Element ◽  
Strong Earthquakes ◽  
Three Dimensional Models ◽  
Conditional Limit ◽  
Decision Making Tool

Multi-drum columns are articulated structures, made of several discrete bulgy stone blocks (drums) placed one on top of the other without mortar. The multi-drum column is a typical structural element of temples of the Classical, Hellenistic and earlier Roman period. Despite the lack of any lateral load resisting mechanism, these columns have survived several strong earthquakes over the centuries. The Chapter focuses on the effect of past drum dislocations on the vulnerability of classical columns and presents a performance-based framework for their seismic risk assessment. The vulnerability is numerically calculated through response estimations using detailed three-dimensional models based on the Discrete Element Method. Conditional limit-state probabilities are calculated and appropriate performance criteria are suggested. The proposed methodology is able to pinpoint cases where past damage affects the vulnerability of such structures and can serve as a valuable decision-making tool.

Sight distance red zones on combined horizontal and sag vertical curves

1998 ◽  
Vol 25 (4) ◽  
pp. 621-630 ◽  
Author(s):  
Yasser Hassan ◽  
Said M Easa
Keyword(s):  
Quantitative Analysis ◽  
Three Dimensional ◽  
The Other ◽  
Two Dimensional ◽  
Horizontal Curve ◽  
Sight Distance ◽  
Stopping Sight Distance ◽  
Three Dimensional Models ◽  
Highway Alignment ◽  
Current Standards

Coordination of highway horizontal and vertical alignments is based on subjective guidelines in current standards. This paper presents a quantitative analysis of coordinating horizontal and sag vertical curves that are designed using two-dimensional standards. The locations where a horizontal curve should not be positioned relative to a sag vertical curve (called red zones) are identified. In the red zone, the available sight distance (computed using three-dimensional models) is less than the required sight distance. Two types of red zones, based on stopping sight distance (SSD) and preview sight distance (PVSD), are examined. The SSD red zone corresponds to the locations where an overlap between a horizontal curve and a sag vertical curve should be avoided because the three-dimensional sight distance will be less than the required SSD. The PVSD red zone corresponds to the locations where a horizontal curve should not start because drivers will not be able to perceive it and safely react to it. The SSD red zones exist for practical highway alignment parameters, and therefore designers should check the alignments for potential SSD red zones. The range of SSD red zones was found to depend on the different alignment parameters, especially the superelevation rate. On the other hand, the results showed that the PVSD red zones exist only for large values of the required PVSD, and therefore this type of red zones is not critical. This paper should be of particular interest to the highway designers and professionals concerned with highway safety.Key words: sight distance, red zone, combined alignment.

Study of the Effect of Boundary Conditions on Residual Stresses in Welding Using Element Birth and Element Movement Techniques

2003 ◽  
Vol 125 (4) ◽  
pp. 432-439 ◽  
Author(s):  
Ihab F. Z. Fanous ◽  
Maher Y. A. Younan ◽  
Abdalla S. Wifi
Keyword(s):  
Residual Stresses ◽  
Boundary Conditions ◽  
Three Dimensional ◽  
Welding Process ◽  
Computation Time ◽  
The Other ◽  
Two Dimensional ◽  
The Media ◽  
Three Dimensional Models ◽  
Element Movement

The structure in which the welding process is performed highly affects the residual stresses generated in the welding. This effect is simulated by choosing the appropriate boundary conditions in modeling the welding process. The major parameters of the boundary conditions are the method by which the base metal is being fixed and the amount of heat being applied through the torch. Other parameters may include the coefficients of thermal heat loss from the plate which may simulate the media in which the welding is taking place. In modeling the welding process, two-dimensional forms of approximation were developed in analyzing most of the models of such problem. Three-dimensional models analyzing the welding process were developed in limited applications due to its high computation time and cost. With the development of new finite element tools, namely the element movement technique developed by the authors, full three-dimensional analysis of the welding process is becoming in hand. In the present work, three different boundary conditions shall be modeled comparing their effect on the welding. These boundary conditions shall be applied to two models of the welding process: one using the element birth technique and the other using the element movement technique showing the similarity in their responses verifying the effectiveness of the latter being accomplished in a shorter time.

Reconstruction tridimensionnelle du chondriome de Ginkgo en culture tissulaire; étude au moyen de coupes épaisses et de coupes fines sériées

1979 ◽  
Vol 57 (4) ◽  
pp. 332-340 ◽  
Author(s):  
René Rohr
Keyword(s):  
Electron Microscope ◽  
Cultured Cells ◽  
Three Dimensional ◽  
The Other ◽  
Important Place ◽  
Thin Sections ◽  
Dimensional Models ◽  
Complete Cell ◽  
Three Dimensional Models

The observation of thick sections and serial thin sections with the electron microscope demonstrates a reticular organization of mitochondria in cultured cells from Ginkgo. Thick sections show that most of the mitochondria fuse either in loose networks made up of elongated elements or in dense clusters composed of globular units. Serial thin sections enable us to prove the true reticular nature of the mitochondrial organization; most of the mitochondrial profiles are part of highly fused and branched networks. These mitochondrial reticula (about two to three per cell) occupy an important place within the cell. Some mitochondria remain isolated or they fuse slightly. Two three-dimensional models have been built: the first one constructed with cardboard sheets is used to display the organization of a reticulum; the other of Plexiglas clearly indicates the relative positions and the form of mitochondria in a complete cell. The mitochondria, plastids, and vacuoles of this cell are also measured and enumerated.

scholarly journals (5RS)-5-(4-Methoxyphenyl)-2-(methylsulfanyl)benzo[g]pyrimido[4,5-b]quinoline-4,6,11(3H,5H,12H)-trione, withZ′ = 3, forms a three-dimensional hydrogen-bonded framework containing five types of hydrogen bond

2013 ◽  
Vol 70 (1) ◽  
pp. 50-54 ◽  
Author(s):  
Yelder A. Castillo ◽  
Luis F. Zapata ◽  
Jorge Trilleras ◽  
Justo Cobo ◽  
Christopher Glidewell
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
The Other ◽  
Framework Structure ◽  
Structural Element ◽  
Molecular Conformations ◽  
The Third ◽  
Compound C ◽  
Independent Molecules

The title compound, C23H17N3O4S, crystallizes withZ′ = 3 in the space groupP\overline{1}. Two of the three independent molecules are broadly similar in terms of both their molecular conformations and their participation in hydrogen bonds, but the third molecule differs from the other two in both of these respects. The molecules are linked by a combination of N—H...O, N—H...N, C—H...O, C—H...N and C—H...π(arene) hydrogen bonds to form a continuous three-dimensional framework structure within which a centrosymmetric six-molecule aggregate can be identified as a key structural element.

Valenciennes and Banqueting Hall: Theatre Research in Three and Four Dimensions

1981 ◽  
Vol 22 (2) ◽  
pp. 161-170
Author(s):  
Robert K. Sarlós
Keyword(s):  
Three Dimensional ◽  
The Other ◽  
Four Dimensions ◽  
Personal Involvement ◽  
Other Hand ◽  
Hand Performance ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
And Performance

In a recent essay I argued for broader acceptance of two methods for understanding “past styles of performance”—the building of three dimensional models and the staging of four dimensional performance reconstructions. These alternatives to the traditional narrative essay make greater use of theatrical imagination, and aim at raising new kinds of questions rather than answering the old kind. However, lack of appropriate apparatus has prevented widespread use of these forms. Since performances are by nature “short-lived phenomena” and can be recorded but fragmentarily, unique methods are required for their study. Theoretical reconstructions cannot approximate the physical and psychological ambience of a respectable performance essay. On the other hand, performance reconstructions do not allow for scholarly caveat during presentation, or for lacunae where knowledge is lacking. Therefore I see the promise of a rich harvest in two-way stimulation between theoretical and performance essays. A pair of reports, based on personal involvement in the types of projects I advocate, follows.

The Simulation of Rolling Process of Bar

2014 ◽  
Vol 898 ◽  
pp. 245-248
Author(s):  
Jin Hong Ma ◽  
Bin Tao ◽  
Xiao Han Yao
Keyword(s):  
Finite Element Analysis ◽  
Three Dimensional ◽  
Rolling Process ◽  
The Other ◽  
Stress And Strain ◽  
Roll Force ◽  
Analysis Software ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Three Dimensional Models

The three-dimensional models of rolling are established with Pro/E. Based on the finite element analysis software ANSYS/LS-DYNA, the procedure of bar tandem rolling is simulated. The nephograms of stress and strain of bar deformed area and the curve of roll force during rolling are obtained. Compared the result with the other result which comes from optimization, the precision of calculation will be verified.

Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

1990 ◽  
Vol 48 (1) ◽  
pp. 258-259
Author(s):  
J.L. Carrascosa ◽  
G. Abella ◽  
S. Marco ◽  
M. Muyal ◽  
J.M. Carazo
Keyword(s):  
Three Dimensional ◽  
The Other ◽  
Two Dimensional ◽  
Series Method ◽  
Three Dimensional Reconstruction ◽  
Structural Components ◽  
E Coli ◽  
Dimensional Reconstruction ◽  
Morphogenetic Factors ◽  
Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models

Validation of a Belt Model for Prediction of Hub Forces from a Rolling Tire4

2009 ◽  
Vol 37 (2) ◽  
pp. 62-102 ◽  
Author(s):  
C. Lecomte ◽  
W. R. Graham ◽  
D. J. O’Boy
Keyword(s):  
Internal Pressure ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Prediction Method ◽  
Analytical Models ◽  
Beam Model ◽  
Impedance Boundary ◽  
Bending Waves ◽  
Tire Rotation ◽  
Three Dimensional Models

Abstract An integrated model is under development which will be able to predict the interior noise due to the vibrations of a rolling tire structurally transmitted to the hub of a vehicle. Here, the tire belt model used as part of this prediction method is first briefly presented and discussed, and it is then compared to other models available in the literature. This component will be linked to the tread blocks through normal and tangential forces and to the sidewalls through impedance boundary conditions. The tire belt is modeled as an orthotropic cylindrical ring of negligible thickness with rotational effects, internal pressure, and prestresses included. The associated equations of motion are derived by a variational approach and are investigated for both unforced and forced motions. The model supports extensional and bending waves, which are believed to be the important features to correctly predict the hub forces in the midfrequency (50–500 Hz) range of interest. The predicted waves and forced responses of a benchmark structure are compared to the predictions of several alternative analytical models: two three dimensional models that can support multiple isotropic layers, one of these models include curvature and the other one is flat; a one-dimensional beam model which does not consider axial variations; and several shell models. Finally, the effects of internal pressure, prestress, curvature, and tire rotation on free waves are discussed.

An Efficient Multiple Description Coding for Multi-View Video Based on the Correlation of Spatial Polyphase Transformed Subsequences

2019 ◽  
Vol 63 (5) ◽  
pp. 50401-1-50401-7 ◽  
Author(s):  
Jing Chen ◽  
Jie Liao ◽  
Huanqiang Zeng ◽  
Canhui Cai ◽  
Kai-Kuang Ma
Keyword(s):  
Video Transmission ◽  
Video Sequence ◽  
Three Dimensional ◽  
The Other ◽  
Multiple Description Coding ◽  
Multiple Description ◽  
Prediction Mode ◽  
Gradient Based ◽  
Directional Interpolation ◽  
Description Coding

Abstract For a robust three-dimensional video transmission through error prone channels, an efficient multiple description coding for multi-view video based on the correlation of spatial polyphase transformed subsequences (CSPT_MDC_MVC) is proposed in this article. The input multi-view video sequence is first separated into four subsequences by spatial polyphase transform and then grouped into two descriptions. With the correlation of macroblocks in corresponding subsequence positions, these subsequences should not be coded in completely the same way. In each description, one subsequence is directly coded by the Joint Multi-view Video Coding (JMVC) encoder and the other subsequence is classified into four sets. According to the classification, the indirectly coding subsequence selectively employed the prediction mode and the prediction vector of the counter directly coding subsequence, which reduces the bitrate consumption and the coding complexity of multiple description coding for multi-view video. On the decoder side, the gradient-based directional interpolation is employed to improve the side reconstructed quality. The effectiveness and robustness of the proposed algorithm is verified by experiments in the JMVC coding platform.

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