1,720,988 research outputs found
Training con “hand.paddles” nel nuoto a crawl
No full textLe palette palmari sono da sempre utilizzate nel nuoto per aumentare la forza specifica della bracciata e, negli ultimi anni, come strumento per migliorare la tecnica. rimangono, però, molti dubbi sulla scelta delle dimensioni delle hand-paddles e sulla metodologia di allenamento adeguata. E’ noto, dall’esperienza da campo, che vi siano contraddittorie considerazioni sugli effetti indotti dal loro uso. E proprio a causa delle scarse conoscenze si lascia agli atleti la scelta del tipo di palette con le quali allenarsi, in una serie di produzioni molto diversificate. Questo si basa quasi esclusivamente su considerazioni e sensazioni personali. L’obiettivo di questo articolo è di approfondire alcuni aspetti di questo complicato problema e proporre metodologie di allenamento specifico
Techniques and considerations for monitoring swimmers’ passive drag
No full textDrag is the resistant force that opposes a swimmer displacing through water and significantly affects swimming performance. Drag experienced during active swimming is called active drag (D a ), and its direct determination is still controversial. By contrast, drag experienced while gliding in a stable streamlined body position is defined as passive drag (D p ), and its assessment is widely agreed upon. D p reduction preserves the high velocity gained with the push-off from the starting block or wall after starting and turning or improves the gliding phase of the breaststroke cycle. Hence, this paper reviewed studies on swimming that measured D p under different conditions of gliding. In the present research, accurate descriptions of the main methods used to directly or indirectly determine D p are provided and the main advantages, limitations and critical features of each method are discussed. Since D p differs in methods but not in reported values and is consistent regardless of the measuring method, the information provided in this paper might allow coaches and practitioners to identify the most suitable method for assessing and determining the drag of their swimmers
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
Le prestazioni dei costumi – valutazione con un software sperimentale
No full textTra le varie componenti che condizionano la performance natatoria, oltre alle variabili dipendenti dal nuotatore stesso, un fattore estremamente rilevante e che ha consentito negli ultimi anni l'abbattimento di parecchi record è rappresentato dal costume di gara. Abbandonati i tessuti ottenuti dalla lavorazione dei polimeri per decisioni FINA, i produttori hanno dovuto realizzare nuovi costumi. Dopo alcune considerazioni sulle componenti della performance natatoria, si è voluto sperimentare sul campo un nuovo software procedendo al confronto di alcuni nuovi costumi in nuotatori di alto livello
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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