Esta dissertação apresenta um novo método de segmentação de movimento baseado na obtenção dos contornos e em filtros morfológicos. A nova técnica apresenta vantagens em relação ao número de falsos positivos e falsos negativos em situações específicas quando comparada às técnicas tradicionais. / This work presents a novel motion segmentation technique based in contours and in morphological filters. It presents advantages in the number of false positives and false negatives in some situations when compared to the classic techniques.

The current study examined how repetitive exposure of an opponent’s stroke preferences on video affected the integration of contextual priors and kinematic information during anticipation in skilled boxers. We performed an experimental ingroup-design with a temporal-occlusion video-based anticipation task with repeated measures where 19 male skilled boxers (M = 22.95 age, SD = 4.26) classified as A boxers in Sweden participated in the study. The test represented three different stroke combinations divided into four tests and two exposure videos. Each test included 22 occluded clips divided into two blocks and each block contained six high-probability strokes, three moderate-probability strokes and two low- probability strokes. The participants were informed to answer which stroke they anticipated and how sure they were of their answer after each clip. Retrospective verbal reports were answered regarding what information the participants used to anticipate the strokes in the preceding test. The purpose of the exposure videos was to manipulate the participants’ to-be- anticipated action in favor of the opponent’s stroke preferences both when the opponent acted and did not act accordingly. The result indicated that participants learned kinematic information about the opponent by observing the opponent on video rather than learning about the opponent’s stroke preferences. Future research is needed to fully understand how contextual priors integrate with kinematic information in boxing. / Föreliggande studie undersökte hur repetitiv exponering av en motståndares slagpreferenser på video påverkade integrationen av kontextuell förhandsinformation och kinematisk information under antecipering hos skickliga boxare. Vi utförde en experimentell inomgruppsdesign med en videobaserad temporal-ocklusion anticiperingsuppgift med upprepade mätningar där 19 skickliga manliga boxare (M = 22.95 ålder, SD = 4.26) klassade som A-boxare i Sverige deltog i studien. Testet representerade tre olika slagkombinationer uppdelade i fyra tester och två exponerings videor. Varje test inkluderade 22 ockluderade klipp uppdelade i två block där varje block innehöll sex slag med hög sannolikhet, tre slag med måttlig sannolikhet och två slag med låg sannolikhet. Deltagarna informerades om att svara vilket slag de anteciperade och hur säkra de var på sitt svar efter varje klipp. Retrospektiva verbala rapporter besvarades angående vilken information deltagarna använde för att antecipera slagen i det föregående testen. Syftet med exponerings videorna var att manipulera deltagarnas antecipering till förmån för motståndarens slag preferenser både när motståndaren agerade och inte agerade därefter. Resultatet visade att deltagarna lärde sig kinematisk information om motståndaren genom att observera motståndaren på video snarare än att lära sig om motståndarens slag preferenser. Framtida forskning behövs för att öka förståelsen för hur kontextuell förhandsinformation integreras med kinematisk information i boxning.

Studiens syfte var att undersöka hur dirigenter för symfoniorkester och storband använder olika tecken i sin kommunikation samt att se om det fanns tydliga likheter och skillnader mellan de olika orkesterformerna. I studien har ett socialsemiotiskt och multimodalt perspektiv använts. Dirigenterna har analyserats utifrån bland annat vilka teckensystem de använder i sin kommunikation med musikerna. Videoobservation har använts som metod och materialet har tagits från siten www.youtube.com Urvalet har bestått i inspelningar av världskända professionella dirigenter som dirigerar professionella orkestrar, några av de bästa inom sitt fält. Resultatet påvisar att dirigenterna ofta använder många teckensystem simultant. Dirigenterna använder en del gemensamma tecken men även många personliga tecken för sin kommunikation. Det framkom vissa skillnader mellan genrerna men då resultaten även skiljde sig mellan dirigenterna inom samma genre krävs mer studier för att ge ett slutgiltigt resultat. Överlag behövs fler studier på dirigering inom storbandsorkester. / The aim of this study was to investigate how conductors representing two different orchestral traditions - the symphony orchestra and big band- use different signs for communication and to explore whether there are any clear differences and similarities between them. Throughout the analysis, a social semiotic and multimodal perspective was applied. The conductors have been analysed by which signs they use when communicating with the musicians. Video observation was used as a method and the material has been retrieved from www.youtube.com. The selection contains recordings of professional and world-famous conductors, working with world renowned orchestras. The result of the study seems to reveal that the conductors utilize and communicate with many sign systems simultaneously and that they use mutual signs as well as personal signs when communicating. There were differences between the two genres but also between conductors within the same genre so further studies are needed to establish a more thorough conclusion. Overall, there is a need for further and larger studies regarding big band orchestras.

Over a decade ago, beekeepers noticed that the bees were dying or disappearing without any prior health disorder. Colony Collapse Disorder (CCD) has been a major threat to bee colonies around the world which affects vital human crop pollination. Possible instigators of CCD include viral and fungal diseases, decreased genetic diversity, pesticides and a variety of other factors. The interaction among any of these potential facets may be resulting in immunity loss for honey bees and the increased likelihood of collapse. It is essential to rescue honey bees and improve the health of bee colony. Monitoring the traffic of bees helps to track the status of hive remotely. An Electronic beehive monitoring system extracts video, audio and temperature data without causing any interruption to the bee hives. This data could provide vital information on colony behavior and health. This research uses Artificial Intelligence and Computer Vision methodologies to develop and analyze technologies to monitor omnidirectional bee traffic of hives without disrupting the colony. Bee traffic means the number of bees moving in a given area in front of the hive over a given period of time. Forager traffic is the number of bees coming in and/or leaving the hive over a time. Forager traffic is a significant component in monitoring food availability and demand, colony age structure, impacts of pests and diseases, etc on hives. The goal of this research is to estimate and keep track of bee traffic by eliminating unnecessary information from video samples.

Cyclist underreporting of lower severity and single cyclist collisions to police results in the underestimation of the societal costs of lower severity and single cyclist collisions [1], [2]. Prevention strategies for these types of collisions are becoming a popular area of research, and video-based approaches have obvious potential for these cases, allowing for detailed analyses of underreported lower severity and single cyclist falls. Video-based studies have been used to investigate site-specific cyclist safety issues such as railway crossings [3 ]. They have also been used for near-collision or near-miss incidents and Surrogate Measures of Safety (SMoS), e.g., [4]. A recent Irish study has identified the most common collision configurations and factors with the inclusion of unreported cases [5]. Findings indicate that falls involving interactions with light rail tram tracks are common in Dublin; they were the most common infrastructural collision partner in this study and a contributing factor in 23% of single cyclist collisions (ibid.), supplementing international findings [6], [7]. Furthermore, along with increasing popularity of cycling, many new light rail systems are being implemented across Europe as part of a broader move towards sustainable transport [8]. Accordingly, further investigation is required to avoid potential conflicts. Therefore, this study aims to use video-based assessment to correlate fall risk with trajectories and crossing angles. [From: Introductiojn]

There is a major issue with concussion within contact sports and one of these sports is ice hockey. Concussions have a negative effect on health and repeated concussions, which often occur in ice hockey, can force players to retire early. Since it is such a major problem that can result in serious consequences, a better understanding within the field is needed. This report has focused on speeds right before a player was tackled as well as the players contact body parts. The information was collected by analyzing 10 video clips where a tackle took place that resulted in a concussion. The video clips were analyzed using the software SkillSpector, where 3D speeds were collected for both the attacking and the injured players. The contact body parts were also identified during the analysis. The results were compared to a reference group from an earlier bachelor degree project where tackles that did not result in a concussion were analyzed. The conclusion from this project is that the speeds for the players in the interest group were proven to have a significantly higher mean speed than the players from the earlier project. Furthermore, the results indicate that the tackled players speed can have a larger impact on the outcome of the tackle than the speed of the attacking player. From the results in this project it is shown that, of the tackles that could lead to a concussion, shoulder to jaw was the most common combination. / Det finns ett stort problem med hjärnskakningar inom kontaktsporter och en utav dessa sporter är ishockey. Hjärnskakningar påverkar hälsan negativt och vid upprepade hjärnskakningar, som ofta uppstår i ishockey, kan spelare tvingas förtidspensioneras. Eftersom att det är ett stort problem som kan ge allvarliga konsekvenser behövs en bättre förståelse inom ämnet. Denna rapport har fokuserat på att ta fram farter precis innan en tackling har skett samt spelarnas kontaktdelar (islagsdelar). Informationen har samlats in genom analysering av 10 stycken videoklipp där en tackling har resulterat i en hjärnskakning. Analysen av videoklippen genomfördes i mjukvaran SkillSpector där 3D farter har tagits fram för både den attackerande och skadade spelaren. Vid analyserna identifierades också islagsdelarna. Resultaten har jämförts med en referensgrupp från ett tidigare kandidatexamensarbete där tacklingar som inte resulterat i en hjärnskakning har analyserats. Slutsatsen från detta arbete är att farterna för spelarna i intressegruppen som drabbats av hjärnskakning hade en högre signifikant medelfart än motsvarande spelarna från det tidigare arbetet. Vidare indikerade resultaten att den tacklades fart är en faktor som kan ha en stor påverkan på utfallet av tacklingen. Från resultatet i detta arbete visas det att av tacklingar som kan leda till hjärnskakning är axel mot käke den vanligaste kombinationen.

Ice hockey is a contact sport with a high risk of brain injuries such as concussions. This is a serious health concern and there is a need of better understanding of the relationship between the kinematics of the head and concussions. The velocity and the direction of impact are factors that might affect the severity of the concussions. Therefore the understanding of concussions can be improved by extracting velocities from video analysis. In this thesis a prototype to extract 3D velocities from one single camera view was developed by using target tracking algorithms and homography. A validation of the method was done where the mean error was estimated to 21.7%. The prototype evaluated 60 cases of tackles where 30 resulted in concussions and the other 30 tackles did not result in concussions. No significant difference in the velocities between the two groups could be found. The mean velocity for the tackles that resulted in concussions were 6.55 m/s for the attacking player and 4.59 m/s for the injured player. The prototype was also compared with velocities extracted through SkillSpector from a previous bachelor thesis. There was a significant difference between the velocities compiled with SkillSpector and the developed prototype in this thesis. A validation of SkillSpector was also made, which showed that it had a mean error of 37.4%. / Ishockey är en kontaktsport med hög risk för hjärnskador, så som hjärnskakningar. Detta är ett stort hälsoproblem och det finns ett behov av större förståelse mellan huvudets kinematik och hjärnskakningar. Hastigheten och riktningen av kollisionerna är faktorer som kan påverka svårighetsgraden av hjärnskakningarna. Därför kan förståelsen av hjärnskakningar förbättras genom att extrahera hastigheter med videoanalys. I denna rapport utvecklades en prototyp för att ta fram 3D hastigheter från en kameravinkel genom att använda målsökningsalgoritmer och homografi. En validering av prototypen gjordes där medelfelet uppskattades till 21.7%. Prototypen utvärderade även 60 fall av tacklingar där 30 resulterade hjärnskakningar och där de andra 30 tacklingarna inte resulterade i hjärnskakningar. Ingen signifikant skillnad mellan de två grupperna kunde påvisas. Medelhastigheten för tacklingarna som resulterade i hjärnskakning var 6.55 m/s för den attackerande spelaren och 4.59 m/s för den skadade spelaren. Prototypen jämfördes också med hastigheter som tagits fram med SkillSpector i ett tidigare kandidatexamensarbete. Det var en signifikant skillnad mellan de hastigheter som togs fram med prototypen och de som tog fram med SkillSpector. En validering av SkillSpector gjordes också, som visade att medelfelet var 37.4%.

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Den svenska grundskolan har genomgått stora förändringar de senaste decennierna. Utvecklingen av läraryrket har gått från att innebära mycket ensamarbete mot att mer och mer innefatta möjlighet till samarbete med kollegor. Den som arbetar som lärare i den svenska skolan nu på 2020-talet har inte bara möjligheten att samarbeta med kollegor, utan förväntas också göra det. Det används många olika uttryck för att beskriva vad detta samarbete ska innehålla. Lärande samtal, lärande gemenskap och pedagogiskt samarbete är några exempel. Denna studie fokuserar på kollegialt lärande, vilket är ytterligare ett begrepp som används. Studien syftar till att utveckla en skolas kollegiala lärande och följa dess utveckling. Detta i ett projekt där personalen fått vara med och forma både mål, innehåll och upplägg. Studien är utformad för att ta reda på vad lärare reflekterar över i lärande samtal inom ramen för ett gemensamt utvecklingsarbete. Den organisation som skapats för projektet bygger på en struktur för den gemensamma arbetslagstiden och består av en serie aktionsrundor med vardera fyra steg. Stegen innehåller samplanering, genomförande av undervisning, videoobservationer med tillhörande lärande samtal, samt avslutande reflektionssamtal i grupp. Reflektionssamtalen filmades och bildar underlag för studiens analys. I analysen framkommer några teman för vad lärare samtalar om i kollegialt lärande som det skapats en tydlig struktur och organisation för. I resultatet blir det synligt vilken enorm betydelse kommunikation har för lärande. Det framkommer också exempel på vad brist på kommunikation kan leda till. Det blir synligt att lärare till viss del förlitar sig till ett samarbete utan kommunikation, så kallad tyst kommunikation. Resultatet visar också betydelsen av hur det kollegiala lärandet har organiserats i form av tid och strukturer för samtal. Kommunikation i allmänhet är inte tillräckligt för att skapa en lärande kultur på en skola. Det är betydelsefullt med ett klimat som gynnar reflektion, och då även kritisk reflektion. Det tar tid att förändra en skolas inre kultur och skapa nya gemensamma normer och värderingar kring både lärarnas och elevernas lärande vilket ger implikationer till skolledare att låta utvecklingsprocesser med kollegialt lärande få ta tid. Det kan också krävas en påtvingad struktur som hjälper arbetslag att komma igång och hålla fokus på utvecklingsområdet. Samtidigt väcker studien funderingar på vilken inverkan en struktur med givna frågeställningar har på ett lärande samtal. / The Swedish compulsory school has undergone major changes in recent decades. The development of the teaching profession has gone from involving a lot of solo work to an increased opportunity for collaboration with colleagues. Those who work as teachers in the Swedish school now in the 2020s not only have the opportunity to collaborate with colleagues, but also expected to do so. Many different expressions are used to describe what this collaboration should contain. Learning conversations, learning community and pedagogical collaboration are some examples. This study focuses on collegial learning, which is another concept used. The study aims to develop a school's collegial learning and follow its development. This is accomplished in a project where the teachers have been involved in constructing both goals, content and structure. The study is designed to find out what teachers reflect upon in learning conversations within a joint development work. The organization created for the project is based on a structure for the collective time of the team and consists of a series of action rounds with four steps each. The steps include co-planning, implementation of teaching, video observations with associated learning conversations, and concluding reflection conversations in groups. The reflection conversations were filmed to form the basis of the study's analysis. The analysis reveals some topics for what teachers talk about in collegial learning for which a distinct structure and organization has been created. The result shows the enormous importance of communication for learning. There are also examples what lack of communication can lead to. It becomes apparent that teachers to some extent rely on collaboration without communication, so-called silent communication. The results also show the importance of organization of collegial learning in terms of time and conversational structures. Communication in general is not enough to create a learning culture among teachers in school. It is important to have a climate that favors reflection, also including critical reflection. It takes time to change the internal culture of a school and create new collective norms and values regarding learning for both teachers and students. This implies that school leaders should allow development processes with collegial learning to take time. An enforced structure may also be required to help teams get started and stay focused in the development area. At the same time, the study raises questions about the impact a structure with given issues can have on learning conversation.

In this study, I took the quantitative research approach of film statistical stylistic analysis to examine the editing pattern evolution of 130 Hollywood movie trailers over the past 60 years from 1951 to 2015; the prior studies on the overall evolution of the Hollywood movies’ editing pattern are compared and discussed. The results suggest that although the movie trailers are much shorter than the whole movies, the average shot lengths of the trailers still display a declining trend over the past 60 years, and the variations in the shot lengths are also decreasing. Second, the motions within each framedo not change significantly over the years, while the correlation coefficients between the shot lengths and the motions within the shots are moving toward a more negative correlation relationship over time, suggesting that the trailers are subject to an editing evolution trend that the shorter the shot is, the more motions there are within it, and this also aligns with the overall movies’ editing pattern evolution trend. Last, the luminance of the trailers remains almost the same over time, which does not align with the overall movies’ editing pattern evolution of becoming darker and darker over decades. Together these findings suggest that the movie trailers’ editing rhythm evolution in general aligns with that of overall movies over time while the visual editing pattern evolution of color luminance does not. The study results will improve our understanding on how the Hollywood movie trailers’ editing pattern and style have evolved over time and pave the way for future advertising studies and cognitive psychology studies on the audience’s attention, immersion and emotional response to various editing patterns of movie trailers. / Media Studies & Production