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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Selektering och urvalsprocessen inom elitidrott, hur upplevs den i praktiken av elever/spelare : en kvalitativ studie inom fotboll och ishockey / Selection process in elite sports, how is it experienced in reality by students/players : a qualitative study in football and ice hockey

Dottemar, David, Ek Johansson, Johan January 2022 (has links)
Syfte och frågeställning Syftet med studien är att utforska hur elever/spelare resonerar kring sina upplevelser om urval och selekteringsprocessen inom NIU-gymnasium samt elitidrott (fotboll och ishockey) på manliga ungdomssidan från 16 år och uppåt. Syftet är vidare att belysa vilka egenskaper elever/spelare upplever är viktigast vid uttagningsprocessen. Frågeställningar: - Hur upplevs selektering och urvalsprocessen i praktiken av elever/spelare? - I vilken mån upplever elever/spelare att rekryteringsansvariga/skolan tar hänsyn till kriterierna varje NIU-gymnasium ska göra inför urval och selektering? Metod Studien har använt sig av en kvalitativ ansats. Detta då studien avsett att undersöka elever/spelares tankar och åsikter kring urval och selekteringsprocessen. En semistrukturerad intervjuguide har använts vid intervjuerna. Sex intervjuer genomfördes, tre personer verksamma inom fotbollen och tre personer verksamma inom ishockeyn. Deltagarna i studien var mellan 16–20 år gamla och har gått eller går på ett NIU gymnasium samt är aktiva inom sin idrott.  Resultat Vad gäller resultatet framkommer det att kontakter inom idrotten är av stor vikt för att ta sig vidare i selekteringsprocessen, även egenskaper som spelförståelse, drivkraft och inställning är viktigt. När det gäller metoder för uttagningsprocessen så nämns tryouter som en väldigt central del men även scouting förekommer. Flertalet av deltagarna upplever orättvisor vad gäller selekteringsprocessen och kopplar oftast det till kontakterna inom sporten. Sett till användandet av de fem NIU kriterierna är upplevelsen bland majoriteten att man oftast bara tar hänsyn till det första kriteriet, idrottsspecifika färdigheter och förutsättningar. De andra kriterierna hamnar oftast i skymundan och man hoppas kunna lösa dessa under resans gång. Slutsats Slutsatsen vi kan dra utifrån studien är att selekteringsprocessen är ett komplext område som väcker mycket diskussioner. Respondenternas upplevelser varierar angående om det sker en rättvis eller orättvis bedömning vid olika urval. Utifrån respondenternas upplevelser lyder slutsatsen att man tagit sig långt i arbetet med selekteringsprocessen, den kritik som dyker upp är att alla spelare bör få fler chanser och inte selekteras bort redan efter en uttagning. / Aim The purpose of the study was to investigate how students/players reason about their experiences of selection and the selection process within NIU high school and elite sports, football and icehockey on the male youth side from 16 years and up. The purpose was also to illustrate whatattributes that are most important in the selection process. The study is based on the following questions: - How is the selection and selection process experienced in practice by students/players?- In what way do students/players feel that the person in charge of recruitment/the school takes consideration to the criteria that each NIU high school must make before selection? Method The study has used a qualitative method. This is because the study is intended to examine students/players thoughts and opinions about the selection and selection process. A semistructured interviewguide has been used in the interviews. Six interviews were conducted, three people were active in football and three people were active in ice hockey. The participants in the study were between 16–20 years old and have attended or are attending a NIU high school and are active in their sport. Results  It appears that contacts in the sport are of great importance to move forward in the selection process, also attributs such as game understanding, drive and attitude are important. When it comes to methods for the selection process, tryouts are mentioned as a very central part, but scouting also occurs. Most of the participants experience injustices regarding to the selection process and usually link it to the contacts within the sport. In terms of the use of the five NIU criteria, the experience among the majority is that they usually only take consideration into the first criterion, sports-specific skills and conditions. The other criteria usually end up in the shadows and the persons who is responsible hopes to be able to solve these during the journey. Conclusion The selection process is a complex area that raises a lot of discussions. The respondents experiences vary regarding whether there is a fair or unfair assessment in different selections. Based on the respondents experiences, the conclusion is that they have come a long way in the work with the selection process, the criticism that arises is that all players should get more chances and not be selected away already after one selection.
242

Från dröm till verklighet : En kvantitativ studie kring en ishockeyspelares chanser att nå elitnivå / From dream to reality : A quantitative study of an ice hockey player's chances of reaching elite level

Bergman, Viktor January 2020 (has links)
Ice hockey is one of the most popular sports in Sweden. Despite its small population, Sweden is one of the most successful ice hockey nations in the world. But who gets the chance to play on the highest level? and what determines this? North American and German studies have shown that birth date, and wherea player grew up, can have an influence on player development. The purpose of the study was to increase the knowledge of the factors that influence selected 15-year-old ice hockey players' way to the elite level. This study had a qualitative approach and the data was collected from a large database. The study included 2303 players born in 1985, 1987, 1989, 1991 and 1994 whom either had played the Swedish tournament TV-pucken or have established themselves as elite hockey players. The result showed that playing for an elite club and growing up in a large region increased the chance for a player to play on elite level. A reverse RAE appeared in this study, players who was born in the third or fourth quarter of the year had increased chances to play at elite level. The conclusion is that this study contributes to adeeper understanding on selection, the reversed RAE and how the chances increase if you are born in the right place and play for the right club.
243

Birds of a Feather Flock Together: Does Similarity Between Sponsor and Sponsee Predict a Successful Sponsorship? : A Study Based on External Congruence and Women’s Sports

Crnoja, Antonio, Grandell, Jesper January 2023 (has links)
Sponsorship is an essential part of marketing communications within sports (Biscaia et al., 2014). Congruence, or the degree to which a sponsor and an event mesh, is one of the main factors influencing sponsorship memory accuracy (Evans, 2019). It is found that, within women’s sports, demand for research on how to maximize the efficiency of sponsorships exists.The research aims to find if sponsors and sponsees could look towards sponsorships with more external congruence to increase the value of the sponsorship to both the sponsor and sponsee. The study uses a survey to find correlations between the amount of external congruence and the degree to which sponsorship objectives are reached. The External Sponsorship Congruence Scale (ESCS), developed by Evans (2019), is used as a basis for measurement of external congruence. The key finding is that the perceived quality of a brand seems to correlate with having a sponsorship that is high in external congruence. Furthermore, both areas of brand awareness and brand image could possibly see some correlation to external congruence. However, those areas were not found to be statistically significant in this study. These findings are important to develop the concept of external congruence and find possible ways of measuring external congruence. For instance, it is found that the ESCS and its constructs seem to be useable in the field of women’s and niche sports. On a theoretical level, changes to the ESCS’s geographical congruence are proposed and a revised ESCS is presented. Moreover, managers within women’s and niche sports, as well as sponsors of those, can use the findings of this study to improve the chances of finding successful sponsorships.
244

Injury Prediction in Elite Ice Hockey using Machine Learning / Riskanalys och Prediktion av Skador i Elitishockey med Maskininlärning

Staberg, Pontus, Häglund, Emil, Claesson, Jakob January 2018 (has links)
Sport clubs are always searching for innovative ways to improve performance and obtain a competitive edge. Sports analytics today is focused primarily on evaluating metrics thought to be directly tied to performance. Injuries indirectly decrease performance and cost substantially in terms of wasted salaries. Existing sports injury research mainly focuses on correlating one specific feature at a time to the risk of injury. This paper provides a multidimensional approach to non-contact injury prediction in Swedish professional ice hockey by applying machine learning on historical data. Several features are correlated simultaneously to injury probability. The project’s aim is to create an injury predicting algorithm which ranks the different features based on how they affect the risk of injury. The paper also discusses the business potential and strategy of a start-up aiming to provide a solution for predicting injury risk through statistical analysis. / Idrottsklubbar letar ständigt efter innovativa sätt att förbättra prestation och erhålla konkurrensfördelar. Idag fokuserar data- analys inom idrott främst på att utvärdera mätvärden som tros vara direkt korrelerade med prestation. Skador sänker indirekt prestationen och kostar markant i bortslösade spelarlöner. Tidigare studier på skador inom idrotten fokuserar huvudsakligen på att korrelera ett mätvärde till en skada i taget. Den här rapporten ger ett multidimensionellt angreppssätt till att förutse skador inom svensk elitishockey genom att applicera maskininlärning på historisk data. Flera attribut korreleras samtidigt för att få fram en skadesannolikhet. Målet med den här rapporten är att skapa en algoritm för att förutse skador och även ranka olika attribut baserat på hur de påverkar skaderisken. I rapporten diskuteras även affärsmöjligheterna för en sådan lösning och hur en potentiell start-up ska positionera sig på marknaden.
245

Sveriges mest kommersiella liga och det traditionella supporterskapet / Sweden's most commercial league and the traditional supportership

Alexandra, Gustafsson, Emma, Franzén January 2023 (has links)
Syftet med studien var att undersöka hur supporterklubbarna till SHL-föreningarna ser på hanteringen av dem för att vidare koppla det till den kommersiella riktningen SHL-föreningarna innehar. För att svara på syftet har två frågeställningar uppkommit i form av 1) Hur upplever supporterklubbarna i SHL att deras respektive ishockeyföreningar behandlar dem? Och 2) Vilka likheter och skillnader finns det mellan olika SHL-föreningars hantering av supportrarna? Informationsinsamling skedde genom semistrukturerade intervjuer av respondenter aktiva inom supporterklubbar. Den analysmetod som vidare användes var tematisk analys och där uppkom tre huvudteman i form av 1) kommunikation, 2) generellt supporterskap och 3) supporterklubben och föreningens förhållande till varandra. I den genomförda analysen följdes de teoretiska ramverken McDonaldisering och hegemoni med kopplingar till den tidigare forskningen och informationsinhämtningen. Resultat som framkom under studien var att för att de mjuka värdena hos supportrarna skall uppnås behöver de känna sig hörda och respekterade vilket visar på vikten av en fungerande kommunikation mellan supporterklubben och SHL-föreningen. Vidare uppkom resultatet att de supporterklubbarna som har en god kommunikation och relation med SHL-föreningen har en ökad förståelse för de kommersiella besluten. / The purpose of the study was to investigate how the supporters' clubs of the SHL associations view the management of the supporters in order to further connect it to the commercial direction of the SHL-associations. To answer the purpose, two questions have arisen in the form of 1) How do the supporter clubs in the SHL feel that their respective ice hockey associations treat them? and 2) What similarities and differences are there between different SHL associations' handling of the supporters? Information collection took place through semi-structured interviews with respondents active in supporter clubs. The analysis method thematic analysis was used where three main themes in the form of 1) communication, 2) general supportership and 3) the relationship between the supporters' clubs and the association emerged. In the conducted analysis, the theoretical frameworks of McDonaldization and hegemony were followed with connections to the previous research and information gathering. Results that emerged during the study were that in order for the soft values of the supporters to be achieved, they need to feel heard and respected, which shows the importance of a functioning communication between the supporters' club and the SHL-associations. Furthermore, the result emerged that the supporter clubs that have a good communication and relationship with the SHL-associations have an increased understanding of the commercial decisions.
246

Analysis of Head Kinematics in Ice Hockey / Analys av huvudets kinematik i ishockey

Pogosian, David January 2022 (has links)
Ice hockey has been identified as a sport with a high risk for concussions due to it being highly physical. Improvements have been made over the years to improve the protective gear for the players effectively eliminating more severe traumatic brain injuries (TBIs) however mild concussions (mTBI) are still prevalent to this day. One way of predicting these injuries in the recent years is the usage of finite element (FE) analysis to recreate impacts to study the effects of said head kinematics and strain parameters using validated FE models of the brain. In this thesis, video analysis was done on five cases resulting in a concussion and five cases not resulting in concussion from both the Swedish Hockey League (SHL) and the National Hockey League (NHL) to extract the initial velocities and positioning. The average velocity for the injured player and attacking player was 5.12 m/s and 5.08 m/s respectively for the impacts resulting in a concussion. Additionally, the average velocity for the injured player and attacking player was 4.80 m/s and 5.51 respectively for the impacts not resulting in a concussion. The video analysis methodology was also validated using a dataset from a football game and resulted in an average error of 25.4%. The impacts were recreated using the extracted velocities and initial positions in LS-PrePost with the full body FE model THUMS v.4.02 representing a 50th percentile adult male fitted with a helmet previously developed by master thesis students at KTH. The simulations were ran using LS-DYNA. The head kinematics from the head’s center of gravity and brain strain measured called Maximum Principal Strain (MPS) were extracted. Using the MPS values, the 95th percentile was calculated to then determine the likelihood of concussion. The MPS95 ranged from 0.18 to 0.63 for the cases resulting in a likelihood of concussion of 7.48 to 100%. For the cases not resulting in a concussion, the MPS95 values ranged from 0.20 to 0.45 resulting in likelihood of concussion 11.1 to 80.5%. The head kinematics extracted reported similar outcome in terms of risk of suffering concussions. The varying results can be pointed to the drawbacks in the methodology such as the error of the video analysis and the positioning of FE models. / Ishockey har fastställts som en sport med höga risker för hjärnskakning på grund av dess fysiska natur. Med åren har förbättringar gjorts på skyddsutrustningen vilket har avlägsnat allvarligare hjärnskador (TBI) från sporten, men dessvärre förekommer mildare hjärnskakningar än idag. På senare år har användning av finita element (FE) metoder använts för att återskapa kollisionerna för att förutspå dessa skador. Detta görs genom att använda validerade FE modeller av hjärnan för att analysera kinematiken samt töjningarna. I detta arbete gjordes en videoanalys av fem fall som resulterade i hjärnskakning samt fem fall där kollisionen inte resulterade i en hjärnskakning från både den Svenska Hockey Ligan (SHL) och "National Hockey League" (NHL). Från videoanalysen togs de initiala hastigheterna samt positionerna fram. Den genomsnittliga hastigheten för den skadade spelaren respektive attackerande spelaren var 5.12 m/s och 5.02 m/s för fallen där hjärnskakning hade skett. För fallen där hjärnskakning inte hade skett var hastigheten för den skadade respektive attackerande spelaren var 4.80 m/s samt 5.51 m/s. Videoanalysmetoden validerades genom att utföra videoanalysis på en databas från en fotbollsmatch. Valideringen resulterade i ett genomsnittligt fel på 25.4%. Kollisionerna återskapades genom att använda de extraherade initiala hastigheterna och positionerna i LS-PrePost med FE helkroppsdockan THUMS v.4.02 som representerade en 50:e percentil vuxen man utrustad med en ishockeyhjälm som utvecklats av tidigare masterexamensstudenter på KTH. Simuleringarna gjordes genom LS-DYNA. Huvudkinematiken från huvudets tyngdpunkt samt de maximala principiella töjningarna (MPS) i hjärnan extraherades. Från de extraherade MPS värdena kunde den 95:e percentilen uträknas för att bestämma sannolikheten att hjärnskakning sker. För fallen där hjärnskakning skett, varierade MPS95 värdet mellan 0.18 till 0.63 vilket motsvarar en risk för hjärnskakning på 7.48% respektive 100%. För fallen där hjärnskakning inte hade skett varierade MPS95 värdet från 0.20 till 0.45 vilket motsvarar 11.1% respektive 80% risk för hjärnskakning. Den extraherade huvudkinematikens risk för hjärnskakning överensstämde för det mesta med MPS95 sannolikheterna. De varierande resultaten kan hänvisas till de brister i metoden som exempelvis felet i videoanalysen samt positioneringen av FE modeller.
247

FYSIOTERAPEUTERS UPPLEVELSER AV SPELARE OCH DESS BETEENDE VID SKADA OCH REHABILITERING INOM SVENSK ELITISHOCKEY : En kvalitativ undersökning inom en sport med hög skadefrekvens.

Nordlund, Lucas, Bouchaoui, Hakim January 2024 (has links)
SAMMANFATTNING  Bakgrund: Ishockey tillhör en av de idrotterna med högst skadefrekvens. Det finns olika faktorer ur ett biopsykosocialt perspektiv som har inverkan på spelares respons och beteende vid skada och rehabilitering. Fysioterapeuter har som uppgift att stötta patienter i rehabilitering och återgång till målaktivitet. Till författarnas vetskap finns det ingen forskning på fysioterapeuters upplevelse av spelares beteende under en rehabiliteringsprocess inom svensk elitishockey.  Syfte: Syftet med följande studie var att undersöka fysioterapeuters upplevelser kring spelares beteende i relation till rehabiliteringsprocessen vid skada inom svensk elitishockey.  Metod: En kvalitativ design med semistrukturerade intervjuer. Ett ändamålsenligt urval användes där sex fysioterapeuter inkluderades från Hockeyallsvenskan och Svenska Hockeyligan (SHL). En kvalitativ innehållsanalys genomfördes med induktiv ansats.  Resultat: Den tematiska analysen resulterade i fem kategorier och 20 subkategorier. Kategorier som framkom var personliga faktorer påverkar beteende, erfarenhet påverkar beteende, omgivningsfaktorer påverkar beteende, egna prioriteringar påverkar beteende samt kunskap om skada påverkar beslutsfattande.  Slutsats: Studien belyste hur samspelet mellan individ- och omgivningsfaktorer hos spelare påverkar beteende under rehabilitering. Identifiering av dessa faktorer visar att rehabilitering med fördel kan utgå från ett biopsykosocialt perspektiv. Spelares hantering av skada upplevdes variera beroende av olika copingstrategier samt hur skadan värderades. / ABSTRACT  Background: Ice hockey is one of the sports with the highest incidence of injuries. There are different factors seen from a biopsychosocial perspective which all influence the players response and behavior during an injury and rehabilitation. The task of physiotherapists is to support patients in their rehabilitation and return to their target activity. There is a limited knowledge of the experiences of physiotherapists regarding player behavior during a rehabilitation process in Swedish elite ice hockey.  Aim: The aim of this this study was to examine physiotherapists experiences of players behaviors in relations to a rehabilitation process after an injury in Swedish elite ice hockey.  Method: A qualitative design with semi structured interviews. An expedient selection was used with six physiotherapists who were included from Hockeyallsvenskan and Svenska Hockeyligan (SHL). The interviews were analyzed with qualitative content analysis with inductive approach.  Results: The thematic analysis resulted in five categories and 20 subcategories. The categories identified were personal factors affects behavior, experience affects behavior, environmental factors affect behavior, personal priorities affect behavior and knowledge about injury affects decision making.  Conclusion: The study illustrated how the interplay between individual- and environmental factors affected player behavior during rehabilitation. Identification of these factors shows that rehabilitation benefits from a biopsychosocial perspective. The experience was that players management of an injury variated depending on different coping strategies and how the injury was valued.
248

Misconduct! Uppför sig medierna olämpligt mot damhockeyn? : En studie om svenska mediers rapportering om Sveriges ishockeylandslag i OS / Misconduct! Does the media behave inappropriately against women’s hockey? : A study about Swedish media reports on Sweden’s hockey teams in the Olympics

Landin, Simon January 2018 (has links)
Ice hockey is a sport like many others that has been dominated by men throughout history. This shows both when it comes to sporting conditions and what gets exposure in media. This essay studies four Swedish newspapers reporting on the Swedish men’s and women’s hockey teams during the Olympics 1998 and 2018. With the help of a quantitative content analysis it analyzes to which degree the reporting is gender equal and what the difference between 1998 and 2018 is. The result of the essay is more equal now than it was 20 years ago. Women’s hockey gets more exposure in the media, female players are being quoted in the articles to a greater extent and the language in the articles about women’s hockey are more similar to the articles about men’s hockey in 2018. Even though there has been a progression, there is still a long way to go to full equality in the reporting on ice hockey. There was still more than twice as many articles about men’s hockey than women’s hockey in the four analyzed  newspapers in 2018 and men’s hockey is still the norm that women’s hockey is being compared to.
249

Effects on aerobic capacity and oxygen saturation and compliance of external nasal dilator strips in healthy young adult ice hockey players

Rydén, Isac, Gustavsson, Jim January 2024 (has links)
Background: Ice hockey is a fast-paced sport with a high possibility of acquiring dental damage and concussions which can be prevented by mouthguards (MG). Despite this, many athletes choose not to use MG due to drawbacks such as discomfort and restricted airways. Restricted airways provided by MG might be reduced by external nasal dilator strips (ENDS). ENDS could contribute to increased aerobic capacity, blood oxygen saturation and self-reported compliance of ENDS by elevating airflow through the nose. Therefore, ENDS could contribute to enhanced performance and recovery rate while reducing the discomfort of MG that could lead to an increased usage of MG among healthy young adult ice hockey players. Aim: The aim was to study aerobic capacity, and oxygen saturation using mouthguard with and without external nasal dilator strips during submaximal bicycle tests. A second aim was to study the compliance of external nasal dilator strips when using mouthguard in healthy young adult ice hockey players. Method: In this experimental study using a cross-over design 15 young adult ice hockey players were contacted to attend on two separate test occasions, with and without ENDS. Aerobic capacity was measured with a Ekblom-Bak submaximal bicycle test (VO2max) and a pulse oximeter was used to examine oxygen saturation (%SpO2). Post-testing, the participants stated self-reported compliance using ENDS based on the numeric rating scale (0-10, positive-negative attitude of usage). Data are presented as mean and standard deviation. Differences between groups were analyzed with the Wilcoxon- signed rank test based on median (Q1-Q3). Result: Nine participants, aged 18-19 completed both test occasions. This study found that ENDS provided no significant difference in estimated VO2max mean (±SD), with ENDS 63.3 (±5.5) and without ENDS 64.2 (±5.0), nor %SpO2 during standard load. A significant increase showed in %SpO2 for higher individual load by 3%, with ENDS 97.1 (±1.3) and without ENDS 94.1 (±4.5). The participants experienced the test as more strenuous with ENDS than without ENDS applied, without significant difference. Despite this, the participants had a positive attitude towards the usage of ENDS. Conclusion This study regarding healthy young adult ice hockey players showed that ENDS provided no significant difference in aerobic capacity. Oxygen saturation however resulted in a positive significant difference at the higher individual load. The majority of the participants in this study propose a positive compliance with ENDS. The results are interpreted with caution due to the small sample.
250

Accident Reconstruction in Ice Hockey: A Pipeline using Pose and Kinematics Estimation to Personalize Finite Element Human Body Models / Rekonstruktion av olyckor i ishockey: En pipeline som använder pose- och kinematikuppskattning för att anpassa finita element humanmodeller

Even, Azilis Emma Sulian January 2024 (has links)
Ice hockey is a sport whose athletes are at high risk for traumatic head injuries due to the violence of potential impacts with other athletes, ice, or glass during games. In order to develop the best protective strategies for the players, it is necessary to have a deep understanding of accident mechanisms during ice hockey games. Accident reconstructions using the finite element (FE) method are a way to perform a systematic analysis of impact cases, but require input data on the circumstances of the accidents. Thus, this project focused on finding a way to extract the position and velocity of the players involved from readily available videos of ice hockey accidents using motion tracking methods. This project included two parts: pose estimation and velocity estimation. The pose estimation aimed to align a human body model (HBM) with the players' poses and the key steps included estimating 2D joints from impact images, estimating the players' 3D poses, skeleton inferencing, and aligning the results with the baseline HBM via pelvic registration. The velocity estimation defined the initial conditions for simulating the collision and key steps included identifying the players' 2D joints across impact video frames, tracking of the players using a simplified pelvis projection on the rink plane, and estimating the players’ velocity using homography to identify their position on the ice hockey rink. Then, both parts were applied to accident cases from a video database of collisions that occurred during a hockey league season. The cases in which the pipeline was fully applied ultimately resulted in LS-DYNA positioning files for the Total Human Model for Safety (THUMS) model, and problematic cases were used to get an overview of the limits of the chosen methodology. Said limitations were mostly linked to the quality of the source videos, which is highly dependent on the source of the videos and possibly not controllable. Due to this, selection criteria are required, such as checking the blurriness and quality of the videos and the viewing angles to ensure as few occlusions as possible. Overall, this project resulted in a working semi-automatic pipeline for pose and velocity estimation in contact sports collisions, as well as a first set of personalized input information that should allow the reconstruction of ice hockey accidents using FE simulations. / Ishockey är en sport vars utövare löper stor risk att drabbas av traumatiska huvudskador på grund av de våldsamma potentiella kollisionerna med andra utövare, is eller glas under matcherna. För att kunna utveckla de bästa skyddsstrategierna för spelarna är det nödvändigt att ha en djup förståelse för olycksmekanismerna under ishockeymatcher. Olycksrekonstruktioner med hjälp av finita elementmetoden är ett sätt att utföra en systematisk analys av kollisionsfall, men kräver indata om omständigheterna kring olyckorna. Detta projekt fokuserade därför på att hitta ett sätt att extrahera de inblandade spelarnas position och hastighet från lättillgängliga videor av ishockeyolyckor med hjälp av rörelsespårningsmetoder. Projektet bestod av två delar: poseuppskattning och hastighetsuppskattning. Poseuppskattningen syftade till att anpassa en humanmodell till spelarnas poser och de viktigaste stegen omfattade uppskattning av 2D-leder från kollisionsbilder, uppskattning av spelarnas 3D-poser, skelettinferens och anpassning av resultaten till baslinjen HBM via bäckenregistrering. Hastighets-uppskattningen definierade de initiala villkoren för simulering av kollisionen och viktiga steg inkluderade identifiering av spelarnas 2D-led i videobilder av kollisionen, spårning av spelarna med hjälp av en förenklad bäckenprojektion på rinkplanet och uppskattning av spelarnas hastighet med hjälp av homografi för att identifiera deras position på ishockeyrinken. Därefter tillämpades båda delarna på olycksfall från en videodatabas med kollisioner som inträffade under en säsong i en hockeyliga. De fall där pipelinen tillämpades fullt ut resulterade slutligen i LS-DYNA-positioneringsfiler, och problematiska fall användes för att få en överblick över gränserna för den valda metoden. Begränsningarna var främst kopplade till kvaliteten på källvideorna, som är starkt beroende av källan till videorna och eventuellt inte kan kontrolleras. På grund av detta krävs urvalskriterier, t.ex. kontroll av videornas oskärpa och kvalitet samt betraktningsvinklar för att säkerställa så få ocklusioner som möjligt. Sammantaget resulterade detta projekt i en fungerande halvautomatisk pipeline för pose- och hastighetsuppskattning vid kollisioner i kontaktsporter, samt en första uppsättning personlig indatainformation som bör möjliggöra rekonstruktion av ishockeyolyckor med hjälp av simulering med finita element.

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