1,720,988 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Tracking terns:Year-round movement ecology of sandwich terns in a changing marine environment
Full text linkSeabirds are excellent indicators of the health of the marine ecosystem. Studying and monitoring their distribution, abundance, diet and productivity can signal changes in prey availability, pollution, and non-natural mortality. Studying their foraging strategies and particularly (mechanisms in) habitat choice forms an important part of such studies. An important driver of the foraging strategy of seabirds is the way they transport prey to the colonies. Bulk-prey loaders store food during trips and regurgitate that to chicks on return. Single-prey loaders deliver individual prey items to their offspring. This latter strategy constrains the size of their foraging range. The aim of this thesis was to study movement of a single-prey loading seabird in relation to its environment and potential consequences of the interaction with anthropogenic developments at sea.Using modern tracking technology, this thesis presents a total of eleven chapters in which various studies on the foraging ecology and habitat selection of Sandwich Terns Thalasseus sandvicensis are described. These iconic seabirds of the North Sea are single-prey loading seabirds for unpredictable prey items in a heterogeneous foraging habitat close to the coast. This subject received less attention in contrast to long-ranging seabirds further offshore, yet, with the increasing expansion of anthropogenic activities in the coastal zone, it is of particular interest.The work in the thesis therefore not only describes movement and foraging behaviour, but also the effects of interaction between seabirds and anthropogenic developments at sea. To do so several novel methods needed to be developed to track terns and study prey items concurrently (Part I). Using these methods, it was possible to determine and predict habitat use of Sandwich Terns during the breeding season (Part II) as well as movement outside the breeding season (Part III). Finally, several aspects of the effect of anthropogenic activities within their foraging range on their movement ecology were studied (Part IV). The synthesis of the thesis summarizes all findings and discussed what tracking terns can learn us about the foraging ecology of seabirds, how the results can be used and future directions of tracking work on terns and seabirds in general
Tracking terns:Year-round movement ecology of sandwich terns in a changing marine environment
No full textSeabirds are excellent indicators of the health of the marine ecosystem. Studying and monitoring their distribution, abundance, diet and productivity can signal changes in prey availability, pollution, and non-natural mortality. Studying their foraging strategies and particularly (mechanisms in) habitat choice forms an important part of such studies. An important driver of the foraging strategy of seabirds is the way they transport prey to the colonies. Bulk-prey loaders store food during trips and regurgitate that to chicks on return. Single-prey loaders deliver individual prey items to their offspring. This latter strategy constrains the size of their foraging range. The aim of this thesis was to study movement of a single-prey loading seabird in relation to its environment and potential consequences of the interaction with anthropogenic developments at sea.Using modern tracking technology, this thesis presents a total of eleven chapters in which various studies on the foraging ecology and habitat selection of Sandwich Terns Thalasseus sandvicensis are described. These iconic seabirds of the North Sea are single-prey loading seabirds for unpredictable prey items in a heterogeneous foraging habitat close to the coast. This subject received less attention in contrast to long-ranging seabirds further offshore, yet, with the increasing expansion of anthropogenic activities in the coastal zone, it is of particular interest.The work in the thesis therefore not only describes movement and foraging behaviour, but also the effects of interaction between seabirds and anthropogenic developments at sea. To do so several novel methods needed to be developed to track terns and study prey items concurrently (Part I). Using these methods, it was possible to determine and predict habitat use of Sandwich Terns during the breeding season (Part II) as well as movement outside the breeding season (Part III). Finally, several aspects of the effect of anthropogenic activities within their foraging range on their movement ecology were studied (Part IV). The synthesis of the thesis summarizes all findings and discussed what tracking terns can learn us about the foraging ecology of seabirds, how the results can be used and future directions of tracking work on terns and seabirds in general
Local Birds in and around the Offshore Wind Park Egmond aan Zee (OWEZ) (T-0 & T-1)
No full textThe Dutch consortium "NoordzeeWind" operates the first offshore wind farm in Dutch North Sea waters. The park, consisting of 36 turbines on monopiles, is located NW of IJmuiden harbour, some 8 NM off the Dutch mainland coast. Named after the nearest town ashore, the park will be known as "Offshore Wind farm Egmond aan Zee" (OWEZ). A second offshore wind farm has also become operational, the Princess Amalia Windfarm (PAWF). This report deals with distribution patterns of local seabirds in an area of approximately 885 km2 around the OWEZ and PAWF park
Tracking terns:Year-round movement ecology of sandwich terns in a changing marine environment
Full text linkSeabirds are excellent indicators of the health of the marine ecosystem. Studying and monitoring their distribution, abundance, diet and productivity can signal changes in prey availability, pollution, and non-natural mortality. Studying their foraging strategies and particularly (mechanisms in) habitat choice forms an important part of such studies. An important driver of the foraging strategy of seabirds is the way they transport prey to the colonies. Bulk-prey loaders store food during trips and regurgitate that to chicks on return. Single-prey loaders deliver individual prey items to their offspring. This latter strategy constrains the size of their foraging range. The aim of this thesis was to study movement of a single-prey loading seabird in relation to its environment and potential consequences of the interaction with anthropogenic developments at sea.Using modern tracking technology, this thesis presents a total of eleven chapters in which various studies on the foraging ecology and habitat selection of Sandwich Terns Thalasseus sandvicensis are described. These iconic seabirds of the North Sea are single-prey loading seabirds for unpredictable prey items in a heterogeneous foraging habitat close to the coast. This subject received less attention in contrast to long-ranging seabirds further offshore, yet, with the increasing expansion of anthropogenic activities in the coastal zone, it is of particular interest.The work in the thesis therefore not only describes movement and foraging behaviour, but also the effects of interaction between seabirds and anthropogenic developments at sea. To do so several novel methods needed to be developed to track terns and study prey items concurrently (Part I). Using these methods, it was possible to determine and predict habitat use of Sandwich Terns during the breeding season (Part II) as well as movement outside the breeding season (Part III). Finally, several aspects of the effect of anthropogenic activities within their foraging range on their movement ecology were studied (Part IV). The synthesis of the thesis summarizes all findings and discussed what tracking terns can learn us about the foraging ecology of seabirds, how the results can be used and future directions of tracking work on terns and seabirds in general
Tracking terns:Year-round movement ecology of sandwich terns in a changing marine environment
Full text linkSeabirds are excellent indicators of the health of the marine ecosystem. Studying and monitoring their distribution, abundance, diet and productivity can signal changes in prey availability, pollution, and non-natural mortality. Studying their foraging strategies and particularly (mechanisms in) habitat choice forms an important part of such studies. An important driver of the foraging strategy of seabirds is the way they transport prey to the colonies. Bulk-prey loaders store food during trips and regurgitate that to chicks on return. Single-prey loaders deliver individual prey items to their offspring. This latter strategy constrains the size of their foraging range. The aim of this thesis was to study movement of a single-prey loading seabird in relation to its environment and potential consequences of the interaction with anthropogenic developments at sea.Using modern tracking technology, this thesis presents a total of eleven chapters in which various studies on the foraging ecology and habitat selection of Sandwich Terns Thalasseus sandvicensis are described. These iconic seabirds of the North Sea are single-prey loading seabirds for unpredictable prey items in a heterogeneous foraging habitat close to the coast. This subject received less attention in contrast to long-ranging seabirds further offshore, yet, with the increasing expansion of anthropogenic activities in the coastal zone, it is of particular interest.The work in the thesis therefore not only describes movement and foraging behaviour, but also the effects of interaction between seabirds and anthropogenic developments at sea. To do so several novel methods needed to be developed to track terns and study prey items concurrently (Part I). Using these methods, it was possible to determine and predict habitat use of Sandwich Terns during the breeding season (Part II) as well as movement outside the breeding season (Part III). Finally, several aspects of the effect of anthropogenic activities within their foraging range on their movement ecology were studied (Part IV). The synthesis of the thesis summarizes all findings and discussed what tracking terns can learn us about the foraging ecology of seabirds, how the results can be used and future directions of tracking work on terns and seabirds in general
Variations on the Author
Full text link“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
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
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