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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Intermittent Convex Integration for Partial Differential Equations describing Fluid Flows
No full textIntermittent Convex Integration is a technique for constructing weak solutions to non-linear partial differential equations. It originates from Buckmaster and Vicol's celebrated result about non-uniqueness of distributional solutions to the three-dimensional Navier-Stokes equation. Their construction uses highly concentrated functions as building blocks in a recursively defined infinite series. The recursive definition stems from the method De Lellis and Székelyhidi developed for the Euler equation which later led to the proof of Onsager's conjecture by Isett.
Using methods from but other building blocks, Modena and Székelyhidi proved the non-uniqueness of solutions to the transport equation with incompressible velocity fields with Sobolev regularity, relying on a much simpler construction than in the first instance of Intermittent Convex Integration mentioned above. In a similar manner Luo proved the existence of stationary solutions to the Navier-Stokes equation in dimension 4.
Another step in the development was the introduction of temporal intermittency by Cheskidov and Luo - earlier constructions were highly concentrated in the spatial variable but homogeneous in time. This innovation admitted results on the two-dimensional Navier-Stokes equation as well as the transport equation with almost Lipschitz velocity field and almost smooth density.
In a series of works which combine the iterative ansatz from the proof of Onsager's conjecture with methods and building blocks from Intermittent Convex Integration Novack et al. were able to prove an intermittent analog of the conjecture.
The contrary approach, in some sense, was taken by the author of this thesis and Székelyhidi by showing that in most results which use Intermittent Convex Integration, iterations are unnecessary and can be replaced by a simple perturbation argument and applying the Baire category theorem. This allows for stronger results since not only existence but also genericity (in the Baire category sense) of solutions can be concluded.
In this work all these developments are presented in an accessible and transparent manner; to this end we will not follow the historically correct order (which is outlined above) but the didactically optimal one: starting from the proof of Onsager's conjecture (which can be considered classical by now) we introduce 'concentrated Mikado flows' and show how they can be applied to the transport equation and the Navier-Stokes equation.
In the next step we present building blocks which are entirely localised in space and therefore feature optimal concentration properties, and showcase their use in the transport equation.
Then we introduce temporal intermittency as described in and show that it can be used in convex integration independently from spatial intermittency in order to give an elementary proof for non-uniqueness of solutions to the hypodissipative Navier-Stokes equation.
The final step is the introduction of the 'Baire category method' and its application to transport and Navier-Stokes equations.:Contents
Chapter I. Introduction
Chapter II. Turbulent Energy Cascade and Onsager’s Conjecture
1. Observations and Heuristics: Richardson and Kolmogorov
2. Onsager’s conjecture on dissipation of energy
3. Proof of Conservation of energy and why it fails for low regularity
4. A proof of Onsager’s Conjecture by Convex Integration
Chapter III. Intermittency in Turbulence and Intermittent Onsager Conjecture
5. Deviation from Homogeneity in Experiments and Modelling
6. Excursion into dyadic energy cascade models
7. Intermittent Energy Cascade and Onsager’s Conjecture
Chapter IV. Concentrated Mikado Flows and Applications
8. Technical Prerequisites
9. Transport equation with Sobolev fields
10. Navier Stokes equation in dimension four and higher
11. Convex Integration for the Intermittent Onsager Conjecture
Chapter V. Full Dimensional Concentration
12. Building blocks and methods
13. Transport equation with Sobolev fields
14. Three-dimensional Navier-Stokes equation
Chapter VI. Temporal Intermittency
15. Hypodissipative Navier-Stokes equations
16. Two-dimensional Navier-Stokes equation and sharp non-uniqueness
17. Transport with almost Lipschitz fields and almost smooth density
Chapter VII. Baire Category Method for Intermittent Convex Integration
18. Outline of the Baire category method
19. Genericity of three-dimensional Navier-Stokes solutions
20. Genericity of solutions to the transport equation with Sobolev fields
Bibliograph
Intermittent Convex Integration for Partial Differential Equations describing Fluid Flows
No full textIntermittent Convex Integration is a technique for constructing weak solutions to non-linear partial differential equations. It originates from Buckmaster and Vicol's celebrated result about non-uniqueness of distributional solutions to the three-dimensional Navier-Stokes equation. Their construction uses highly concentrated functions as building blocks in a recursively defined infinite series. The recursive definition stems from the method De Lellis and Székelyhidi developed for the Euler equation which later led to the proof of Onsager's conjecture by Isett.
Using methods from but other building blocks, Modena and Székelyhidi proved the non-uniqueness of solutions to the transport equation with incompressible velocity fields with Sobolev regularity, relying on a much simpler construction than in the first instance of Intermittent Convex Integration mentioned above. In a similar manner Luo proved the existence of stationary solutions to the Navier-Stokes equation in dimension 4.
Another step in the development was the introduction of temporal intermittency by Cheskidov and Luo - earlier constructions were highly concentrated in the spatial variable but homogeneous in time. This innovation admitted results on the two-dimensional Navier-Stokes equation as well as the transport equation with almost Lipschitz velocity field and almost smooth density.
In a series of works which combine the iterative ansatz from the proof of Onsager's conjecture with methods and building blocks from Intermittent Convex Integration Novack et al. were able to prove an intermittent analog of the conjecture.
The contrary approach, in some sense, was taken by the author of this thesis and Székelyhidi by showing that in most results which use Intermittent Convex Integration, iterations are unnecessary and can be replaced by a simple perturbation argument and applying the Baire category theorem. This allows for stronger results since not only existence but also genericity (in the Baire category sense) of solutions can be concluded.
In this work all these developments are presented in an accessible and transparent manner; to this end we will not follow the historically correct order (which is outlined above) but the didactically optimal one: starting from the proof of Onsager's conjecture (which can be considered classical by now) we introduce 'concentrated Mikado flows' and show how they can be applied to the transport equation and the Navier-Stokes equation.
In the next step we present building blocks which are entirely localised in space and therefore feature optimal concentration properties, and showcase their use in the transport equation.
Then we introduce temporal intermittency as described in and show that it can be used in convex integration independently from spatial intermittency in order to give an elementary proof for non-uniqueness of solutions to the hypodissipative Navier-Stokes equation.
The final step is the introduction of the 'Baire category method' and its application to transport and Navier-Stokes equations.:Contents
Chapter I. Introduction
Chapter II. Turbulent Energy Cascade and Onsager’s Conjecture
1. Observations and Heuristics: Richardson and Kolmogorov
2. Onsager’s conjecture on dissipation of energy
3. Proof of Conservation of energy and why it fails for low regularity
4. A proof of Onsager’s Conjecture by Convex Integration
Chapter III. Intermittency in Turbulence and Intermittent Onsager Conjecture
5. Deviation from Homogeneity in Experiments and Modelling
6. Excursion into dyadic energy cascade models
7. Intermittent Energy Cascade and Onsager’s Conjecture
Chapter IV. Concentrated Mikado Flows and Applications
8. Technical Prerequisites
9. Transport equation with Sobolev fields
10. Navier Stokes equation in dimension four and higher
11. Convex Integration for the Intermittent Onsager Conjecture
Chapter V. Full Dimensional Concentration
12. Building blocks and methods
13. Transport equation with Sobolev fields
14. Three-dimensional Navier-Stokes equation
Chapter VI. Temporal Intermittency
15. Hypodissipative Navier-Stokes equations
16. Two-dimensional Navier-Stokes equation and sharp non-uniqueness
17. Transport with almost Lipschitz fields and almost smooth density
Chapter VII. Baire Category Method for Intermittent Convex Integration
18. Outline of the Baire category method
19. Genericity of three-dimensional Navier-Stokes solutions
20. Genericity of solutions to the transport equation with Sobolev fields
Bibliograph
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Intermittent Convex Integration for Partial Differential Equations describing Fluid Flows
No full textIntermittent Convex Integration is a technique for constructing weak solutions to non-linear partial differential equations. It originates from Buckmaster and Vicol's celebrated result about non-uniqueness of distributional solutions to the three-dimensional Navier-Stokes equation. Their construction uses highly concentrated functions as building blocks in a recursively defined infinite series. The recursive definition stems from the method De Lellis and Székelyhidi developed for the Euler equation which later led to the proof of Onsager's conjecture by Isett.
Using methods from but other building blocks, Modena and Székelyhidi proved the non-uniqueness of solutions to the transport equation with incompressible velocity fields with Sobolev regularity, relying on a much simpler construction than in the first instance of Intermittent Convex Integration mentioned above. In a similar manner Luo proved the existence of stationary solutions to the Navier-Stokes equation in dimension 4.
Another step in the development was the introduction of temporal intermittency by Cheskidov and Luo - earlier constructions were highly concentrated in the spatial variable but homogeneous in time. This innovation admitted results on the two-dimensional Navier-Stokes equation as well as the transport equation with almost Lipschitz velocity field and almost smooth density.
In a series of works which combine the iterative ansatz from the proof of Onsager's conjecture with methods and building blocks from Intermittent Convex Integration Novack et al. were able to prove an intermittent analog of the conjecture.
The contrary approach, in some sense, was taken by the author of this thesis and Székelyhidi by showing that in most results which use Intermittent Convex Integration, iterations are unnecessary and can be replaced by a simple perturbation argument and applying the Baire category theorem. This allows for stronger results since not only existence but also genericity (in the Baire category sense) of solutions can be concluded.
In this work all these developments are presented in an accessible and transparent manner; to this end we will not follow the historically correct order (which is outlined above) but the didactically optimal one: starting from the proof of Onsager's conjecture (which can be considered classical by now) we introduce 'concentrated Mikado flows' and show how they can be applied to the transport equation and the Navier-Stokes equation.
In the next step we present building blocks which are entirely localised in space and therefore feature optimal concentration properties, and showcase their use in the transport equation.
Then we introduce temporal intermittency as described in and show that it can be used in convex integration independently from spatial intermittency in order to give an elementary proof for non-uniqueness of solutions to the hypodissipative Navier-Stokes equation.
The final step is the introduction of the 'Baire category method' and its application to transport and Navier-Stokes equations.:Contents
Chapter I. Introduction
Chapter II. Turbulent Energy Cascade and Onsager’s Conjecture
1. Observations and Heuristics: Richardson and Kolmogorov
2. Onsager’s conjecture on dissipation of energy
3. Proof of Conservation of energy and why it fails for low regularity
4. A proof of Onsager’s Conjecture by Convex Integration
Chapter III. Intermittency in Turbulence and Intermittent Onsager Conjecture
5. Deviation from Homogeneity in Experiments and Modelling
6. Excursion into dyadic energy cascade models
7. Intermittent Energy Cascade and Onsager’s Conjecture
Chapter IV. Concentrated Mikado Flows and Applications
8. Technical Prerequisites
9. Transport equation with Sobolev fields
10. Navier Stokes equation in dimension four and higher
11. Convex Integration for the Intermittent Onsager Conjecture
Chapter V. Full Dimensional Concentration
12. Building blocks and methods
13. Transport equation with Sobolev fields
14. Three-dimensional Navier-Stokes equation
Chapter VI. Temporal Intermittency
15. Hypodissipative Navier-Stokes equations
16. Two-dimensional Navier-Stokes equation and sharp non-uniqueness
17. Transport with almost Lipschitz fields and almost smooth density
Chapter VII. Baire Category Method for Intermittent Convex Integration
18. Outline of the Baire category method
19. Genericity of three-dimensional Navier-Stokes solutions
20. Genericity of solutions to the transport equation with Sobolev fields
Bibliograph
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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