Oracles of Peace: Topic Modeling, Cultural Opportunity, and the Nobel Peace Prize, 1902–2012*

2016 ◽  
Vol 21 (1) ◽  
pp. 43-64 ◽  
Author(s):  
Ryan Light ◽  
Jeanine Cunningham
Keyword(s):  
Social Movement ◽  
Topic Modeling ◽  
Computational Techniques ◽  
Computational Technique ◽  
Illustrative Case ◽  
Nobel Peace Prize ◽  
Traditional Methods ◽  
Cultural Milieu ◽  
Methodological Advance ◽  
Cultural Structures

Social movement frames are dynamic, shifting and embedded within an already existent cultural milieu—a milieu that affects mobilization opportunities. In this article, we invoke the concept of the “cultural clearinghouse” to tackle how broader cultural structures translate to frames or influence frame resonance. Our illustrative case, the Nobel Peace Prize, along with our use of topic modeling, a computational technique that identifies commonalities between texts, offer an important methodological advance for social movement scholars interested in culture, frame formation and resonance, and dynamic approaches to social movement discourse. Our findings show how peace discourse—as represented by Peace Prize acceptance speeches—increasingly has become embedded within broader cultural emphases on globalization and neoliberalism, versus earlier Christian and global institutional schemas. We conclude by discussing the usefulness of our conceptual and methodological advance for movement scholars with special attention to the coupling of new computational techniques and more traditional methods.

scholarly journals On the relations between some well-known methods and the projective Riccati equations

Open Physics ◽  
2020 ◽  
Vol 18 (1) ◽  
pp. 613-618
Author(s):  
Şamil Akçağıl
Keyword(s):  
Partial Differential Equations ◽  
Differential Equations ◽  
Evolution Equations ◽  
Nonlinear Evolution ◽  
Riccati Equations ◽  
Nonlinear Evolution Equations ◽  
Alternative Methods ◽  
Computational Techniques ◽  
Partial Differential ◽  
Traditional Methods

AbstractSolving nonlinear evolution equations is an important issue in the mathematical and physical sciences. Therefore, traditional methods, such as the method of characteristics, are used to solve nonlinear partial differential equations. A general method for determining analytical solutions for partial differential equations has not been found among traditional methods. Due to the development of symbolic computational techniques many alternative methods, such as hyperbolic tangent function methods, have been introduced in the last 50 years. Although all of them were introduced as a new method, some of them are similar to each other. In this study, we examine the following four important methods intensively used in the literature: the tanh–coth method, the modified Kudryashov method, the F-expansion method and the generalized Riccati equation mapping method. The similarities of these methods attracted our attention, and we give a link between the methods and a system of projective Riccati equations. It is possible to derive new solution methods for nonlinear evolution equations by using this connection.

Semi-Elimination Methodology for Simulating High Flow Features in a Reservoir

2021 ◽  
Author(s):  
Yahan Yang ◽  
Ali Samii ◽  
Zhenlong Zhao ◽  
Guotong Ren
Keyword(s):  
High Flow ◽  
Small Cells ◽  
Computational Techniques ◽  
Computational Technique ◽  
System Of Equations ◽  
Time Step ◽  
Linear System Of Equations ◽  
Time Stepping ◽  
Model Complex ◽  
Upstream Weighting

Abstract Despite the rapid rise of computing power and advances in computational techniques in past decades, it is still challenging in reservoir simulation to model complex and detailed features that are represented by small cells with large permeability values, for example, fractures, multi-segment wells, etc. While those features may carry a large amount of flow and thus have a significant impact on the performance prediction, the combination of small volume and large permeability unfortunately leads to well-known time stepping and convergence difficulties during Newton iteration. We address this issue of high flow through small cells by developing a new semi-elimination computational technique. At the beginning of simulation, we construct a set of pressure basis which is a mapping from pressures at surrounding cells in the bulk of reservoir to pressures at those small cells. Next, we start the time-stepping scheme. For each time step or iteration within a time step, small cells are first employed to provide an accurate computation of flow rates and derivatives using upstream weighting and a flow partitioning scheme. Afterwards, small cells are eliminated and a linear system of equations is assembled and solved involving only bulk cells. This semi-elimination technique allows us to fundamentally avoid the drawbacks caused by including small cells in the global system of equations, while capturing their effect on the flow of hydrocarbon in the reservoir. One of the advantages of the proposed techniques over other existing methods is that it is fully implicit and preserves upstream weighting and compositions of the flow field even after small cells are eliminated, which enhances numerical stability and accuracy of simulation results. Application of this technique to several synthetic and field models demonstrates significant performance and accuracy improvement over standard approaches. This method thus offers a practical way to model complex and dynamic flow behaviors in important features without incurring penalties in speed and robustness of the simulation.

Structural Topic Modeling For Social Scientists: A Brief Case Study with Social Movement Studies Literature, 2005–2017

2019 ◽  
Vol 6 (4) ◽  
pp. 307-318 ◽  
Author(s):  
Nathan C. Lindstedt
Keyword(s):  
Social Movement ◽  
Topic Modeling ◽  
Research Process ◽  
Computer Assisted ◽  
Sociological Research ◽  
Social Scientists ◽  
Modeling Framework ◽  
Social Scientific ◽  
Structural Topic Modeling

Sociologists frequently make use of language as data in their research using methodologies including open-ended surveys, in-depth interviews, and content analyses. Unfortunately, the ability of researchers to analyze the growing amount of these data declines as the costs and time associated with the research process increases. Topic modeling is a computer-assisted technique that can help social scientists to address these data challenges. Despite the central role of language in sociological research, to date, the field has largely overlooked the promise of automated text analysis in favor of more familiar and more traditional methods. This article provides an overview of a topic modeling framework especially suited for social scientific research. By way of a case study using abstracts from social movement studies literature, a short tutorial from data preparation through data analysis is given for the method of structural topic modeling. This example demonstrates how text analytics can be applied to research in sociology and encourages academics to consider such methods not merely as novel tools, but as useful supplements that can work beside and enhance existing methodologies.

Using Transfer Matrices for Parametric System Forced Response

1987 ◽  
Vol 109 (4) ◽  
pp. 356-360 ◽  
Author(s):  
J. W. David ◽  
L. D. Mitchell ◽  
J. W. Daws
Keyword(s):  
Harmonic Balance ◽  
Forced Response ◽  
Computational Techniques ◽  
Computational Technique ◽  
Transfer Matrices ◽  
Frequency Branch ◽  
Balance Technique ◽  
Systems Analysts ◽  
The Many ◽  
Harmonic Balance Technique

For many years, engineers and scientists have sought to deal with the many phenomena exhibiting parametric characteristics. While many approximate techniques are available for the analysis of such systems, the harmonic balance technique can be used to accurately model the response of systems where the coefficient variation is large. Also, in analyzing complex physical systems, analysts have sought to develop efficient computational techniques that are sufficiently general for the analysis of arbitrary systems. In this paper, it is shown that combining the harmonic balance technique with transfer matrices produces an efficient computational technique for the analysis of parametric systems where the coefficient variations can be large. The technique is demonstrated by considering a single-degree-of-freedom system with time varying stiffness. The harmonic balance technique is used to frequency-branch the transfer matrices, thus allowing multifrequency response calculations to be done simultaneously. The results are compared with direct numerical integrations of the equations. Lastly, this technique is applied to a simple gear coupled rotor system to demonstrate the application of this technique to large order systems of more engineering relevance.

scholarly journals Trends in Contemporary Art Discourse: Using Topic Models to Analyze 25 years of Professional Art Criticism

2018 ◽  
Vol 12 (3) ◽  
pp. 303-324 ◽  
Author(s):  
Henk Roose ◽  
Willem Roose ◽  
Stijn Daenekindt
Keyword(s):  
Contemporary Art ◽  
Topic Modeling ◽  
Art Criticism ◽  
Computational Technique ◽  
Social Forms ◽  
The Social ◽  
Art Magazine ◽  
Heuristic Device ◽  
Art And Society ◽  
The Relationship

In this article, we use topic modeling to systematically explore topics discussed in contemporary art criticism. Analyzing 6965 articles published between 1991 and 2015 in Frieze, a leading art magazine, we find a plurality of topics characterizing professional discourse on contemporary art. Not surprisingly, media- or genre-specific topics such as film/cinema, photography, sculpture/installations, etc. emerge. Interestingly, extra-artistic topics also characterize contemporary art criticism: there is room for articles on new digital technology and on art and philosophy; there is also growing interest in the relationship between art and society. Our analysis shows that despite evolutions in the field of contemporary art – such as the ‘social turn’, in which contemporary art starts paying more attention to social forms and content – the prevalence of certain topics in contemporary art criticism has barely changed over the past 25 years. With this article, we demonstrate the unique value of topic modeling for cultural sociology: it is both a powerful computational technique to generate a bird’s-eye view of a huge text corpus and a heuristic device that locates key texts for further close reading.

Offset Surface Generation and Contouring in Computer-Aided Design

1987 ◽  
Vol 109 (1) ◽  
pp. 133-142 ◽  
Author(s):  
Y. J. Chen ◽  
B. Ravani
Keyword(s):  
Computer Aided Design ◽  
Numerical Control ◽  
Surface Generation ◽  
Computational Techniques ◽  
Computational Technique ◽  
Contour Lines ◽  
Computer Aided ◽  
Offset Surfaces ◽  
Aided Design ◽  
Offset Surface

Two computational techniques are presented for Computer-Aided Design (CAD) and Machining (CAM) of parametrically defined surfaces. One technique deals with construction of offset surfaces. An algorithm is presented that would allow detection and removal of the closed loop on the offset surface due to its self-intersection. The second computational technique presented deals with contouring of parametric surfaces. The technique presented allows for optimal generation of planar contour lines. The results are applied to Numerical Control (NC) machining of surfaces.

Fracture and mechanical behavior of vacuum-assisted microwave cured unidirectional carbon woven fabric reinforced epoxy composite

2020 ◽  
pp. 146442072096703
Author(s):  
Rajeev Kumar ◽  
Himanshu Pathak ◽  
Sunny Zafar
Keyword(s):  
Fracture Energy ◽  
Volume Fraction ◽  
Epoxy Composite ◽  
Mean Field ◽  
Woven Fabric ◽  
Computational Techniques ◽  
Computational Technique ◽  
Fiber Volume ◽  
High Fiber ◽  
Microwave Curing

Woven fabric reinforced epoxy composite shown inherent favorable characteristics for aerospace industry applications. This paper comprehensively investigated the mechanical and fracture behavior of unidirectional carbon woven fabric reinforced epoxy composite using experimental and computational techniques. The composites were fabricated with two, four, and six ply laminates with cross-ply and inclined ply (45/–45) orientations. Laminates were fabricated using Vacuum-Assisted Resin Infusion Microwave Curing technique with a high fiber volume fraction of 50% for each laminate. Experimental analyses were performed to predict the behavior of composites under tensile, shear, and impact loading environment. Further, the mean-field homogenization technique coupled with the finite element method was employed to predict orthotropic material properties, fracture energy, and fracture parameters ( KIC and GIC) of the composite. The results showed that fracture energy obtained by the computational technique was in good agreement with experimental results. The values of GIC increased with the number of plies both for cross and inclined plies orientation composites. KIC values were higher for cross plies laminates than the inclined plies laminates.

COMPUTATIONAL THEORY OF REFLECTION HIGH ENERGY ELECTRON DIFFRACTION

1997 ◽  
Vol 04 (03) ◽  
pp. 513-524 ◽  
Author(s):  
P. A. MAKSYM
Keyword(s):  
Electron Diffraction ◽  
High Energy ◽  
Energy Electron ◽  
Alternative Methods ◽  
Computational Techniques ◽  
Computational Technique ◽  
High Energy Electron ◽  
Crystal Surfaces ◽  
Computational Theory ◽  
The Individual

The theory of reflection high energy electron diffraction (RHEED) by crystal surfaces is reviewed, with special emphasis on computational techniques. Multiple scattering is accounted for by solving the Schrödinger equation exactly to obtain the amplitudes of the diffracted beams above the surface. The surface and substrate are divided into atomic layers and the RHEED intensities for the entire system are determined from the scattering properties of the individual layers. Alternative methods for implementing this approach are explained and compared. Recent applications to analysis of real RHEED data are used to illustrate the general theory and it is shown that it can provide very good agreement with experiment. The computational efficiency of RHEED calculations is examined carefully and key bottlenecks are identified. This leads to a new computational technique which is much faster than existing ones. Some problems connected with the implementation of this approach are examined in detail.

scholarly journals 5D Parameter Estimation of Near-Field Sources Using Hybrid Evolutionary Computational Techniques

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Fawad Zaman ◽  
Ijaz Mansoor Qureshi
Keyword(s):  
Genetic Algorithm ◽  
Interior Point ◽  
Fitness Function ◽  
Near Field ◽  
Pattern Search ◽  
Estimation Accuracy ◽  
Computational Techniques ◽  
Computational Technique ◽  
Interior Point Algorithm ◽  
Validity And Reliability

Hybrid evolutionary computational technique is developed to jointly estimate the amplitude, frequency, range, and 2D direction of arrival (elevation and azimuth angles) of near-field sources impinging on centrosymmetric cross array. Specifically, genetic algorithm is used as a global optimizer, whereas pattern search and interior point algorithms are employed as rapid local search optimizers. For this, a new multiobjective fitness function is constructed, which is the combination of mean square error and correlation between the normalized desired and estimated vectors. The performance of the proposed hybrid scheme is compared not only with the individual responses of genetic algorithm, interior point algorithm, and pattern search, but also with the existing traditional techniques. The proposed schemes produced fairly good results in terms of estimation accuracy, convergence rate, and robustness against noise. A large number of Monte-Carlo simulations are carried out to test out the validity and reliability of each scheme.

A Finite-Differences Derivative-Descent Approach for Estimating Form Error in Precision-Manufactured Parts

2005 ◽  
Vol 128 (1) ◽  
pp. 355-359 ◽  
Author(s):  
Abhijit Gosavi ◽  
Shantanu Phatakwala
Keyword(s):  
Objective Function ◽  
Computational Methods ◽  
Finite Differences ◽  
Analytical Methods ◽  
Critical Role ◽  
Computational Techniques ◽  
Computational Technique ◽  
Error Measurement ◽  
Form Error ◽  
Research Attention

Background: Form-error measurement is mandatory for the quality assurance of manufactured parts and plays a critical role in precision engineering. There is now a significant literature on analytical methods of form-error measurement, which either use mathematical properties of the relevant objective function or develop a surrogate for the objective function that is more suitable in optimization. On the other hand, computational or numerical methods, which only require the numeric values of the objective function, are less studied in the literature on form-error metrology. Method of Approach: In this paper, we develop a methodology based on the theory of finite-differences derivative descent, which is of a computational nature, for measuring form error in a wide spectrum of features, including straightness, flatness, circularity, sphericity, and cylindricity. For measuring form-error in cylindricity, we also develop a mathematical model that can be used suitably in any computational technique. A goal of this research is to critically evaluate the performance of two computational methods, namely finite-differences and Nelder-Mead, in form-error metrology. Results: Empirically, we find encouraging evidence with the finite-differences approach. Many of the data sets used in experimentation are from the literature. We show that the finite-differences approach outperforms the Nelder-Mead technique in sphericity and cylindricity. Conclusions: Our encouraging empirical evidence with computational methods (like finite differences) indicates that these methods may require closer research attention in the future as the need for more accurate methods increases. A general conclusion from our work is that when analytical methods are unavailable, computational techniques form an efficient route for solving these problems.

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