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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
Detection and Tracking of Players in Sport Video
No full textPraćenje igrača u sportskom videu korisno je za analizu strategije i kretanja istih, te služi kao svojevrsni izazov znanstvenoj zajednici koji se odluče baviti njim. Uzeli smo pristup praćenja po detekciji zato što je intuitivan i učinkovit. Za algoritam praćenja odabrali smo DeepSORT, a za detektore YOLO v4 i njegovu manju varijantu, YOLO v4-tiny, koja je pogodnija za izvedbu u stvarnom vremenu.
Naučili smo mreže na podacima nogometnih utakmica i prate 3 klase: igrača, vratara i suca. Na našoj lokalnoj konfiguraciji, praćenje s prilagođenom YOLO v4 mrežom je prosječne brzine 5 okvira po sekundi, a MOTA i MOTP mjere na ispitnom videu su 62.9% i 32.3% respektivno. Modificirana YOLO v4-tiny varijanta izvršava se brzinom od 10 okvira po sekundi i na ispitnom je videu MOTA 46.5%, a MOTP 33.3%. Uzevši ubrzanje objekata u obzir prilikom računanja, uspjeli smo malo poboljšati rezultate DeepSORT-a. YOLO v4 mreža pokazuje robusnost na smetnje poput sakrivanja zbog svoje visoke preciznosti, dok tiny varijanta pruža bolje sučelje za pokretne sustave kod kojih je preciznost manje važna.Tracking players in sports videos is useful for motion and strategy analysis and is a challenge on its own. For this paper, we chose the tracking-by-detection approach as it is intuitive and effective. For tracking, we chose DeepSORT, one of the most prominent trackers today. For detection, we chose two detectors: YOLO v4, which is more complex and robust; and YOLO v4-tiny, which is better for detection in real-time.
We trained the networks to discern between 3 classes: player, goalkeeper, and referee. At 5 FPS on our local machine, tracking with our custom YOLO v4 network gets a MOTA score of 62.9% and a MOTP score of 32.3%. Our custom YOLOv4-tiny, while performing tracking at 10 FPS, gets a MOTA score of 46.5% and a MOTP of 33.3%. When taking object acceleration into consideration, we have managed to slightly improve DeepSORT results. Each of these networks is suitable for its intended purpose: YOLO v4 is shown to be noise-resistant due to its high precision and recall, whereas YOLO v4-tiny is fast and would be a viable application for mobile systems that are more forgiving of detection errors
Detection of Players in Football Game Video
No full textRad pokriva detekciju igrača na nogometnoj utakmici korištenjem algoritma oduzimanja pozadine. Objašnjeno je što je algoritam oduzimanja pozadine te kako se koristi. Nabrojali smo rekurzivne i nerekurzivne tehnike odvajanja pozadine od objekata u prvom planu. Spomenuti su i dodatni algoritmi koje je bilo moguće razmatrati u okviru rješavanja ovog problema te smo detaljno razmotrili one korištene u implementaciji: MOG2 i KNN. Rješenje je implementirano u programskom jeziku Python i komentiraju se korištene funkcije. Dokumentirana je izrada maske za detekciju objekata u prvom planu. Za naglašavanje i lakšu detekciju igrača na snimci koristili smo morfološke transformacije. Dobivene rezultate označili smo omeđujućim pravokutnicima. Napravili smo evaluaciju uspješnosti detekcije s pripadnim referentnim okvirima i izračunali smo preciznost i odziv.The subject of this thesis is football player detection using a background subtraction algorithm. The background subtraction algorithm is explained and how we used it in implementing the solution. The recursive and non-recursive techniques in background subtraction have been mentioned, as well as other algorithms which we could have used in the solution. The background subtractors MOG2 and KNN, which we used in the implementation are explained. The program was written in the Python programming language and the functions used in the implementation, both ours and imported, are mentioned and commented on. We have covered making the foreground mask from our initial image set. To make player detection easier and more successful, morphological transformations were used. Then, we marked our detections with predicted bounding boxes. After that, the detection was evaluated using respective ground-truth models for each detection and with this data the mean values of precision and recall were calculated
Diagnosis and Prevention injury of Hamstrings Muscles
No full textU sportu te sportsko rekreativnim aktivnostima najčešće zastupljene ozljede koje se javljaju kod sportaša su ozljede hamstringsa. Takva vrsta ozljeda nastaje uslijed mnogobrojnih čimbenika među kojima su najčešći brza promjena smjera kretanja, nagla zaustavljanja, sprintevi, udarci po lopti, a sve to događa se tijekom ekscentrične kontrakcije i stvaranja velike sile. Svrha ovog rada je prikazati samu anatomsku građa mišića te njegove zadaće, vrste ozljede, rehabilitacijske postupke te načine prevencije i dijagnostike. Mišićna skupina se sastoji od 3 mišića. M.biceps femoris, m.semintendinosus i m.semimembranosus od kojih svaki od navedenih mišića sudjeluje u lokomociji ljudskog tijela i izvođenju različitih pokreta nogu, a inervirani su n.ischiadicusom. Preventivni mehanizmi podrazumjevaju primjenu različitih programa vježbi izometrične, koncentrične i najčešće primjenjene ekscentrične kontrakcije, a jedna od najčešće izvođenijih takvih vježbi je Nordic hamstrings koja prema brojnim istraživanjima uz ostale vježbe smanjuje stopu ozljeda i povećava snagu mišića. Kako bi se postotak ovakvih vrsta ozljeda smanjio te kako nebi došlo do narušavanja sportskih performansi značajna je redovna primjena preventivnih programa vježbanja. Preventivni programi mogu se provoditi u uvodnom i glavnom dijelu treninga, ali i kao zaseban trening sportaša. Ukoliko dođe do ozljeda efikasnim provođenjem dijagnostičkih postupaka započinje proces rehabilitacije. Dijagnostika podrazumjeva analizu povijesti ozljeda, klinički pregled, palpaciju, usporedbu sa neozljeđenom nogom te različite vrste testova koje čine osnovu za početak provođenja rehabilitacijskih procesa. Danas, nerijetko korištena klinička dijagnoza podrazumjeva ultrazvuk i magnetsku rezonancu kao alat za definiranje ozljede i vrijeme potrebno za povratak u sport. Kvalitetna dijagnostika usmjerava proces rehabilitacije, ubrzava oporavak i priprema sportaša na povratak u svakodnevni trening ili sportsko natjecanje ovisno o mjeri sportaševe uključenosti u sport.In sports and recreational activities, the most prevalent injuries among athletes are hamstring injuries. This type of injury arises due to numerous factors, with the most common being rapid changes in direction, sudden stops, sprints, ball impacts, all of which occur during eccentric contractions and the generation of significant force. The purpose of this professional work is to present the anatomical structure of the muscle itself, its functions, types of injuries, rehabilitation procedures, as well as methods of prevention and diagnosis. The muscle group consists of three muscles: the m. biceps femoris, m. semitendinosus, and m. semimembranosus. Each of these muscles contributes to the locomotion of the human body and the execution of various leg movements, innervated by the n. ischiadicus. Preventive mechanisms involve the application of different exercise programs, including isometric, concentric, and most commonly used eccentric contractions. One of the frequently performed exercises is the Nordic hamstring exercise, which, according to numerous studies, along with other exercises, reduces the injury rate and increases muscle strength. In order to decrease the percentage of such injuries and to avoid compromising athletic performance, regular implementation of preventive exercise programs is crucial. These preventive programs can be incorporated into both the warm-up and the main part of training, as well as being conducted as separate training sessions for athletes. Efficient diagnostic procedures initiate the rehabilitation process in case of injuries. The diagnostic process involves analyzing injury history, clinical examination, palpation, comparison with the uninjured leg, and various types of tests that form the basis for commencing rehabilitation processes. Today, clinical diagnosis often includes the use of ultrasound and magnetic resonance imaging as tools for defining the injury and estimating the time required for return to sport. High-quality diagnostics guide the rehabilitation process, accelerate recovery, and prepare the athlete for re-entry into everyday training or competitive sports, depending on the extent of the athlete's involvement in the sport
Diagnosis and Prevention injury of Hamstrings Muscles
No full textU sportu te sportsko rekreativnim aktivnostima najčešće zastupljene ozljede koje se javljaju kod sportaša su ozljede hamstringsa. Takva vrsta ozljeda nastaje uslijed mnogobrojnih čimbenika među kojima su najčešći brza promjena smjera kretanja, nagla zaustavljanja, sprintevi, udarci po lopti, a sve to događa se tijekom ekscentrične kontrakcije i stvaranja velike sile. Svrha ovog rada je prikazati samu anatomsku građa mišića te njegove zadaće, vrste ozljede, rehabilitacijske postupke te načine prevencije i dijagnostike. Mišićna skupina se sastoji od 3 mišića. M.biceps femoris, m.semintendinosus i m.semimembranosus od kojih svaki od navedenih mišića sudjeluje u lokomociji ljudskog tijela i izvođenju različitih pokreta nogu, a inervirani su n.ischiadicusom. Preventivni mehanizmi podrazumjevaju primjenu različitih programa vježbi izometrične, koncentrične i najčešće primjenjene ekscentrične kontrakcije, a jedna od najčešće izvođenijih takvih vježbi je Nordic hamstrings koja prema brojnim istraživanjima uz ostale vježbe smanjuje stopu ozljeda i povećava snagu mišića. Kako bi se postotak ovakvih vrsta ozljeda smanjio te kako nebi došlo do narušavanja sportskih performansi značajna je redovna primjena preventivnih programa vježbanja. Preventivni programi mogu se provoditi u uvodnom i glavnom dijelu treninga, ali i kao zaseban trening sportaša. Ukoliko dođe do ozljeda efikasnim provođenjem dijagnostičkih postupaka započinje proces rehabilitacije. Dijagnostika podrazumjeva analizu povijesti ozljeda, klinički pregled, palpaciju, usporedbu sa neozljeđenom nogom te različite vrste testova koje čine osnovu za početak provođenja rehabilitacijskih procesa. Danas, nerijetko korištena klinička dijagnoza podrazumjeva ultrazvuk i magnetsku rezonancu kao alat za definiranje ozljede i vrijeme potrebno za povratak u sport. Kvalitetna dijagnostika usmjerava proces rehabilitacije, ubrzava oporavak i priprema sportaša na povratak u svakodnevni trening ili sportsko natjecanje ovisno o mjeri sportaševe uključenosti u sport.In sports and recreational activities, the most prevalent injuries among athletes are hamstring injuries. This type of injury arises due to numerous factors, with the most common being rapid changes in direction, sudden stops, sprints, ball impacts, all of which occur during eccentric contractions and the generation of significant force. The purpose of this professional work is to present the anatomical structure of the muscle itself, its functions, types of injuries, rehabilitation procedures, as well as methods of prevention and diagnosis. The muscle group consists of three muscles: the m. biceps femoris, m. semitendinosus, and m. semimembranosus. Each of these muscles contributes to the locomotion of the human body and the execution of various leg movements, innervated by the n. ischiadicus. Preventive mechanisms involve the application of different exercise programs, including isometric, concentric, and most commonly used eccentric contractions. One of the frequently performed exercises is the Nordic hamstring exercise, which, according to numerous studies, along with other exercises, reduces the injury rate and increases muscle strength. In order to decrease the percentage of such injuries and to avoid compromising athletic performance, regular implementation of preventive exercise programs is crucial. These preventive programs can be incorporated into both the warm-up and the main part of training, as well as being conducted as separate training sessions for athletes. Efficient diagnostic procedures initiate the rehabilitation process in case of injuries. The diagnostic process involves analyzing injury history, clinical examination, palpation, comparison with the uninjured leg, and various types of tests that form the basis for commencing rehabilitation processes. Today, clinical diagnosis often includes the use of ultrasound and magnetic resonance imaging as tools for defining the injury and estimating the time required for return to sport. High-quality diagnostics guide the rehabilitation process, accelerate recovery, and prepare the athlete for re-entry into everyday training or competitive sports, depending on the extent of the athlete's involvement in the sport
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
Diagnosis and Prevention injury of Hamstrings Muscles
No full textU sportu te sportsko rekreativnim aktivnostima najčešće zastupljene ozljede koje se javljaju kod sportaša su ozljede hamstringsa. Takva vrsta ozljeda nastaje uslijed mnogobrojnih čimbenika među kojima su najčešći brza promjena smjera kretanja, nagla zaustavljanja, sprintevi, udarci po lopti, a sve to događa se tijekom ekscentrične kontrakcije i stvaranja velike sile. Svrha ovog rada je prikazati samu anatomsku građa mišića te njegove zadaće, vrste ozljede, rehabilitacijske postupke te načine prevencije i dijagnostike. Mišićna skupina se sastoji od 3 mišića. M.biceps femoris, m.semintendinosus i m.semimembranosus od kojih svaki od navedenih mišića sudjeluje u lokomociji ljudskog tijela i izvođenju različitih pokreta nogu, a inervirani su n.ischiadicusom. Preventivni mehanizmi podrazumjevaju primjenu različitih programa vježbi izometrične, koncentrične i najčešće primjenjene ekscentrične kontrakcije, a jedna od najčešće izvođenijih takvih vježbi je Nordic hamstrings koja prema brojnim istraživanjima uz ostale vježbe smanjuje stopu ozljeda i povećava snagu mišića. Kako bi se postotak ovakvih vrsta ozljeda smanjio te kako nebi došlo do narušavanja sportskih performansi značajna je redovna primjena preventivnih programa vježbanja. Preventivni programi mogu se provoditi u uvodnom i glavnom dijelu treninga, ali i kao zaseban trening sportaša. Ukoliko dođe do ozljeda efikasnim provođenjem dijagnostičkih postupaka započinje proces rehabilitacije. Dijagnostika podrazumjeva analizu povijesti ozljeda, klinički pregled, palpaciju, usporedbu sa neozljeđenom nogom te različite vrste testova koje čine osnovu za početak provođenja rehabilitacijskih procesa. Danas, nerijetko korištena klinička dijagnoza podrazumjeva ultrazvuk i magnetsku rezonancu kao alat za definiranje ozljede i vrijeme potrebno za povratak u sport. Kvalitetna dijagnostika usmjerava proces rehabilitacije, ubrzava oporavak i priprema sportaša na povratak u svakodnevni trening ili sportsko natjecanje ovisno o mjeri sportaševe uključenosti u sport.In sports and recreational activities, the most prevalent injuries among athletes are hamstring injuries. This type of injury arises due to numerous factors, with the most common being rapid changes in direction, sudden stops, sprints, ball impacts, all of which occur during eccentric contractions and the generation of significant force. The purpose of this professional work is to present the anatomical structure of the muscle itself, its functions, types of injuries, rehabilitation procedures, as well as methods of prevention and diagnosis. The muscle group consists of three muscles: the m. biceps femoris, m. semitendinosus, and m. semimembranosus. Each of these muscles contributes to the locomotion of the human body and the execution of various leg movements, innervated by the n. ischiadicus. Preventive mechanisms involve the application of different exercise programs, including isometric, concentric, and most commonly used eccentric contractions. One of the frequently performed exercises is the Nordic hamstring exercise, which, according to numerous studies, along with other exercises, reduces the injury rate and increases muscle strength. In order to decrease the percentage of such injuries and to avoid compromising athletic performance, regular implementation of preventive exercise programs is crucial. These preventive programs can be incorporated into both the warm-up and the main part of training, as well as being conducted as separate training sessions for athletes. Efficient diagnostic procedures initiate the rehabilitation process in case of injuries. The diagnostic process involves analyzing injury history, clinical examination, palpation, comparison with the uninjured leg, and various types of tests that form the basis for commencing rehabilitation processes. Today, clinical diagnosis often includes the use of ultrasound and magnetic resonance imaging as tools for defining the injury and estimating the time required for return to sport. High-quality diagnostics guide the rehabilitation process, accelerate recovery, and prepare the athlete for re-entry into everyday training or competitive sports, depending on the extent of the athlete's involvement in the sport
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
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
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