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Improving Objectivity and Reliability of Observational Risk Assessment Tools by using Technical Instruments / Observationsmetoder för ergonomisk riskbedömning – ökad objektivitet och tillförlitlighet med hjälp av tekniska mätningarCharsmar-Etor, Cephas January 2023 (has links)
Ergonomic assessments to determine risks of work-related musculoskeletal disorders as well as to compare designs of work-tasks and workstations, are imperative for high sustainability and productivity in any given industry. Hence, assessment tools that can objectively and reliably capture postures, joint angles and muscle activities play very important role in properly determining risks relating to work and various tasks. The introduction of direct measurement instruments/tools has been helping and continue to help improve upon observational assessment methods to attain objectivity and reliability. This project aimed at contributing to future improvements of industrial risk assessment measures in ergonomics by identifying and testing direct measurement instruments/tools that can enhance observational risk assessment methods and introduce a new way of signal processing, hence, reducing assessment time while increasing objectivity and reliability. Several candidate instruments were identified and out of the identified, ten were selected as potential candidates. Two out of the ten, Wergonic and ErgoHandMeter were then selected and tested on common observation risk assessment factors that could be measured and answers provided directly or by analyses. The Wergonic instrument was modified to enhance its measuring capability from one fully and partially two factors to six factors. New algorithms were also employed to analyse measurements of the ErgoHandMeter in order to answer questions regarding repetitive movements. The two instruments tested, are able to measure and provide results for six commonly and one rarely assessed biomechanical risk factors. By combining selected potential candidates, many of the commonly targeted biomechanical risk factors in observational instruments can be measured by the selected direct measurement instruments. However, some factors especially force measurement remain a challenge for measuring by direct wearable sensor instruments.
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Technika a metodika nácviku Ikedovy katy s džó v aikidó / Technique and methodology of training of Ikeda's kata exercise with jo in aikidoVáclavík, Pavel January 2012 (has links)
Title: Technique and methodology of training of Ikeda's kata exercise with jo in aikido. Aim: The aim of this diploma thesis is to describe systematically and explain the exercise techniques of kata with jo of Ikeda Sensei on the basis of available resources and the author's personal experience. The author aims to extend the possible forms of study of these techniques through multimedia processing for both professionals and public interested in martial arts. Tasks: To gather the necessary theoretical and practical information and data needed for processing the theme To select and design tools for the elaboration of kata teaching methodology. Practical implementation: to divide kata analytically into sub-parts, to describe these parts and to take their photographic and video record. Create a video on DVD. To elaborate the textual and graphic part of the diploma thesis and to print the final version. Methods of work: The thesis is a theoretical-descriptive in nature and we use these methods for its implementation: Analysis and study of documents. Historical method. Compilation Comparative method. The method of photography and video. Keywords: aikido, Ikeda's kata exercise with jo, exercise positions with jo, jo, kata, postures in aikidó, movement
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Posture and Space in Virtual Characters : application to Ambient Interaction and Affective Interaction / Posture et Espace chez les Personnages Virtuels : application à l'Interaction Ambiante et AffectiveTan, Ning 31 January 2012 (has links)
La communication multimodale, qui est primordiale dans les relations interpersonnelles, reste encore très limitée dans les interfaces homme-machine actuelles. Parmi les différentes modalités qui ont été adoptées par les recherches en interaction homme-machine, la modalité posturale a été moins explorée que d’autres modalités comme la parole ou les expressions faciales. Les postures corporelles sont pourtant indispensables pour interpréter et situer l’interaction entre deux personnes, que ce soit en termes de contexte spatial ou de contexte social. Les briques de base que sont les dispositifs et les modalités d’interaction (par exemple la kinect ou les avatars) sont pourtant disponibles. Il manque cependant des modèles informatiques reliant ces médias et modalités aux fonctions de communication pertinentes dans les interactions interpersonnelles comme celles liées à l’espace ou aux émotions.L’objectif de cette thèse est de concevoir un premier modèle informatique permettant d’exploiter les postures dans les interactions homme-machine. Cela soulève plusieurs questions de recherche : comment représenter symboliquement des postures exprimées durant des interactions interpersonnelles ? Comment spécifier les comportements posturaux de personnages virtuels ? Quelles doivent être les caractéristiques d’un modèle d’interaction corporel permettant des interactions entre un personnage virtuel et un utilisateur dans différents contextes physiques ou sociaux ?L’approche proposée consiste dans un premier temps à prendre comme point de départ des corpus vidéo filmés dans différentes situations. Nous avons défini un schéma de codage pour annoter manuellement les informations posturales à différents niveaux d’abstraction et pour les différentes parties du corps. Ces représentations symboliques ont été exploitées pour effectuer des analyses des relations spatiales et temporelles entre les postures exprimées par deux interlocuteurs.Ces représentations symboliques de postures ont été utilisées dans un deuxième temps pour simuler des expressions corporelles de personnages virtuels. Nous nous sommes intéressés à un composant des émotions particulièrement pertinent pour les études sur les postures : les tendances à l’action. Des animations impliquant deux personnages virtuels ont été ainsi conçues puis évaluées perceptivement.Enfin, dans un troisième temps, les expressions corporelles d’un personnage virtuel ont été conçues dans une application mixte faisant intervenir un personnage virtuel et un utilisateur dans un cadre d’interaction ambiante. Les postures et gestes du personnage virtuel ont été utilisées pour aider l’utilisateur à localiser des objets du monde réel.Cette thèse ouvre des perspectives sur des études plus spécifiques de l’interaction corporelle nécessitant par exemple des annotations automatiques via des dispositifs de capture de mouvement ou la prise en compte des différences individuelles dans l’expression posturale. / Multimodal communication is key to smooth interactions between people. However, multimodality remains limited in current human-computer interfaces. For example, posture is less explored than other modalities, such as speech and facial expressions. The postural expressions of others have a huge impact on how we situate and interpret an interaction. Devices and interfaces for representing full-body interaction are available (e.g., Kinect and full-body avatars), but systems still lack computational models relating these modalities to spatial and emotional communicative functions.The goal of this thesis is to lay the foundation for computational models that enable better use of posture in human-computer interaction. This necessitates addressing several research questions: How can we symbolically represent postures used in interpersonal communication? How can these representations inform the design of virtual characters' postural expressions? What are the requirements of a model of postural interaction for application to interactive virtual characters? How can this model be applied in different spatial and social contexts?In our approach, we start with the manual annotation of video corpora featuring postural expressions. We define a coding scheme for the manual annotation of posture at several levels of abstraction and for different body parts. These representations were used for analyzing the spatial and temporal relations between postures displayed by two human interlocutors during spontaneous conversations.Next, representations were used to inform the design of postural expressions displayed by virtual characters. For studying postural expressions, we selected one promising, relevant component of emotions: the action tendency. Animations were designed featuring action tendencies in a female character. These animations were used as a social context in perception tests.Finally, postural expressions were designed for a virtual character used in an ambient interaction system. These postural and spatial behaviors were used to help users locate real objects in an intelligent room (iRoom). The impact of these bodily expressions on the user¡¯s performance, subjective perception and behavior was evaluated in a user studyFurther studies of bodily interaction are called for involving, for example, motion-capture techniques, integration with other spatial modalities such as gaze, and consideration of individual differences in bodily interaction.
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Ouvidos de Mercado: novas configurações da comunicação e de consumo digital na cena paulistana / Market Ears: new configurations of communication and digital consumption in the scene of São PauloBento, Igor da Costa 25 March 2010 (has links)
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Previous issue date: 2010-03-25 / The process of symbiosis between information networks and the urban areas gives rise to an informational dimension of ubiquitous access to cyberspace that promotes the emergence of a myriad of new social practices from the appropriation of these networks and a variety of connection devices (cell phones, palms, MP3 players, etc.). Nomadic listening is one of the social practices identified in the current urban scene. It can be seen as a semiotic modulation, also social, cognitive, corporal and it works on the coupling between mobile devices and the act of roaming through the city. This new form of consumption focuses on listening to digital music and mounting customized playlists as soundtracks for the day to day. From a conceptual framework that focuses on the intersection between media and consumption, this paper aims to map the nomadic listening in the urban scene and to understand how the music industry has incorporated this practice into their promotion and commercialization strategies. / O processo de simbiose entre as redes telemáticas e a malha urbana enseja uma dimensão informacional de acesso ubíquo ao ciberespaço, que propicia o surgimento de uma miríade de novas práticas sociais a partir da apropriação destas redes e dos mais variados dispositivos de conexão (celulares, palms, MP3 players, etc.). A escuta nômade é uma das práticas sociais identificadas na cena urbana atual. Ela pode ser entendida como uma modulação semiótica, social, cognitiva e corporal, e funciona no acoplamento entre aos dispositivos móveis e o vagar pela cidade. Esta nova forma de consumo privilegia a escuta de música digital e a montagem de playlists personalizadas como trilhas sonoras para o dia a dia. Partindo de uma estrutura conceitual que privilegia a interseção entre mídia e consumo, este trabalho pretende mapear a escuta nômade na cena urbana e compreender de que modo a indústria da música tem incorporado esta prática às suas estratégias de promoção e comercialização.
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Posture and Space in Virtual Characters : application to Ambient Interaction and Affective InteractionTan, Ning 31 January 2012 (has links) (PDF)
Multimodal communication is key to smooth interactions between people. However, multimodality remains limited in current human-computer interfaces. For example, posture is less explored than other modalities, such as speech and facial expressions. The postural expressions of others have a huge impact on how we situate and interpret an interaction. Devices and interfaces for representing full-body interaction are available (e.g., Kinect and full-body avatars), but systems still lack computational models relating these modalities to spatial and emotional communicative functions.The goal of this thesis is to lay the foundation for computational models that enable better use of posture in human-computer interaction. This necessitates addressing several research questions: How can we symbolically represent postures used in interpersonal communication? How can these representations inform the design of virtual characters' postural expressions? What are the requirements of a model of postural interaction for application to interactive virtual characters? How can this model be applied in different spatial and social contexts?In our approach, we start with the manual annotation of video corpora featuring postural expressions. We define a coding scheme for the manual annotation of posture at several levels of abstraction and for different body parts. These representations were used for analyzing the spatial and temporal relations between postures displayed by two human interlocutors during spontaneous conversations.Next, representations were used to inform the design of postural expressions displayed by virtual characters. For studying postural expressions, we selected one promising, relevant component of emotions: the action tendency. Animations were designed featuring action tendencies in a female character. These animations were used as a social context in perception tests.Finally, postural expressions were designed for a virtual character used in an ambient interaction system. These postural and spatial behaviors were used to help users locate real objects in an intelligent room (iRoom). The impact of these bodily expressions on the user¡¯s performance, subjective perception and behavior was evaluated in a user studyFurther studies of bodily interaction are called for involving, for example, motion-capture techniques, integration with other spatial modalities such as gaze, and consideration of individual differences in bodily interaction.
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Contribution à l'analyse et à l'interprétation du mouvement humain: application à la reconnaissance de posturesGirondel, Vincent 19 June 2006 (has links) (PDF)
Le travail de recherche présenté dans ce mémoire de thèse est dédié à l'analyse et à l'interprétation du mouvement humain avec application à la reconnaissance de postures. L'analyse et l'interprétation du mouvement humain en vision par ordinateur ont de nombreux domaines d'applications tels que la vidéosurveillance, les applications de réalité mixte et les interfaces homme-machine avancées. Nous proposons ici un système temps-réel permettant une analyse et une interprétation du mouvement humain.<br /><br />L'analyse du mouvement humain fait intervenir plusieurs processus de traitement d'images tels que la segmentation d'objets en mouvement, le suivi temporel, la détection de peau, les modèles de corps humain et la reconnaissance d'actions ou de postures. Nous proposons une méthode de suivi temporel en deux étapes permettant de suivre au cours du temps une ou plusieurs personnes même si elles s'occultent entre elles. Cette méthode est basée sur un calcul d'intersection de boîtes englobantes rectangulaires et sur un filtrage partiel de Kalman. Puis nous explicitons une méthode de détection de peau par une approche couleur afin de localiser leurs visages et leurs mains. Toutes ces étapes préliminaires donnent accès à de nombreuses informations bas-niveau. Dans une dernière partie, nous utilisons une partie de ces informations pour reconnaître les postures statiques de personnes parmi les quatre postures suivantes: debout, assis, accroupi et couché. De nombreux résultats illustrent les avantages et les limitations des méthodes proposées, ainsi que leur efficacité et robustesse.
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The Work Environment of Welding Operators at Volvo Group Trucks Operations : An Investigation to Reduce the Risk of Musculoskeletal Disorders Among WeldersJonsson Roos, Linda January 2018 (has links)
This master thesis report presents a 20 weeks long project within Industrial design engineering at Luleå University of Technology, performed at Volvo Group Trucks Operations in Umeå. Since the company from a previous study knew that the operators on segment two work in unfavorable work postures, a further investigation of the operators’ work environment was needed. Therefore, the subject of investigation in this project became the physical workload and more specifically, the factors related to the appearance of work related musculoskeletal disorders (MSDs). Segment two is positioned at the end of Volvos’ production line called finishline where the work is primarily done manual by two shift teams with approximately 14 operators in each one. The project objective was to map the current situation for the manual welding operators at segment two and identify potential ergonomic risks within their everyday work. The focus was placed on finding improvements that could decrease the operators’ risk for developing MSDs during work. The project aim was to develop improvements that direct, and over a longer time span, could ease and improve the operators work situation. By observing, filming, interviewing and hand out questionnaires, the current state for the operators could be mapped. Three interviews were held, 22 questionnaires were answered and almost 50 film sequences were made. The work on segment two are station based where the operators are allocated a specific time for each operation within the station. Usually, the operators rotate after ten truck cabs and then move to the next station. The work consists of screwing, welding, grinding, drilling and controlling. The situation analysis was done by investigating the questionnaire responses further, explore the body postural MSD risks with help of RULA and REBA and using the software AviX to let the operators self-estimate the strain in different muscle groups during work. According to the questionnaires, the operators are highly or partly strained physical and psychological where the experienced psychological strain variates more than the physical strain. Furthermore, most of the operators experienced the occurring work acceleration as positive and the manager and coworker relationship as good. Also, ten operators expressed that they had experienced pain in their body the last 12 months caused by their work and over 70 % of the operators wanted to have a greater opportunity to affect the number of work tasks. By relating this to the findings in the study made at Volvo in 2011, where the investigators identified knee-standing work together with some critical work postures that caused the operators an unfavorable strain in mainly the neck, the back and the arms, I assume that the work on segment two today is performed during similar circumstances and in a similar way. The concept development started with an ideation session together with the operators. Here, the analysis findings were discussed, and my own ideas and improvement suggestions were presented. From these discussions, three tests were arranged including a step construction to facilitate when entering and leaving the truck cab, new knee pads and a stretch program, developed by Volvos’ ergonomist. The findings from the two first tests showed how different the operators found the concepts where some operators appreciated both the step construction and the knee pads, and some didn’t. The stretch test on the other hand, were appreciated by all operators where over 50 % felt an improvement in their body. Also, an educational approach including an additional introduction, updated work instructions and a continuous dialogue about work environmental risks during the group meetings were proposed. The tests resulted in a concept development, a concept evaluation with help of previous established specifications of requirements and the ergonomist, together with an implementation strategy. The strategy proposes an implementation of stretch during the workday within the following months, a further investigation of the knee pads and the step construction, and an implementation of the complete educational approach within 5-10 years. Also, based on the results of this thesis, Volvo are recommended to establish guidelines for how to measure work environmental factors linked to physical and psychosocial work environment. Further, the company are recommended to prioritize their employees’ health, well-being and work environment by working systematically in a close cooperation with the workforce to not risk costs in terms of dissatisfaction, sick leaves and poor reputation.
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Supporting Real-Time, Automated Evaluation of Difficulty in Manual AssemblySanthi, B January 2017 (has links) (PDF)
Product designers address the costs of assembly during the design process. Design process can be more efficient if assembly issues could be addressed early in its design process. Doing this requires the ability to assess assemblability among others. Assemblability refers to the ease of assembling the final product from its parts. Assemblability evaluation is applied by product designers for quantitatively estimating the degree of difficulty of the assembly. This helps in identifying areas of improvement, so as to reduce process time and production costs. This work focuses on assessing assemblability in a manual assembly and its importance in the earlier phases of design.
Literature contains various methods for assessing assemblability (e.g. Boothroyd-Dewhurst method, the DFA house, Sturges DFA calculator and Sony DFA method). These methods are typically rule-based and their use requires insight and knowledge on the part of the designer. Further, the designer has to interpret and apply them differently in each specific and unique case. Literature also contains methods for ergonomic assessment of manual work and its link with assemblability. Both observation based ergonomic assessment such as RULA, REBA, VIDAR, LUBA and OWAS and instrumentation based ergonomic assessment using electro-goniometer and accelerometer are the techniques reviewed in this thesis for their suitability in assembly assessment. The most recent trend in the area is automation of the evaluation process. This thesis proposes an approach to automated assessment of assemblability using electromagnetic trackers.
In spite of advances in industrial automation, manual assembly tasks continue to be an important feature of many industrial operations. The method proposed in the thesis is for the assessment of assemblability of manual assembly that combines both time and postural analysis. The tool used for the static analysis is called Rapid Upper Limb Assessment (RULA); for dynamic analysis a new method of time analysis is proposed that is based on the ratio of time spent in fine and gross motions carried out in an assembly process. The difficulty of assembly of a series of manual assembly tasks are carried out in a laboratory setting. Then by correlating this assessment with the feedback on the difficulty of these assembly task obtained from the subjects who carried out these tasks.
The remaining work carried out as a part of this thesis is focussed on automating the process of carrying out the above assessment in an automated manner. Suitability of electromagnetic trackers as a means for automated capture of data necessary for executing the proposed assessment method is studied. Electromagnetic trackers have been used to capture postural data for various limbs of the assembly operators. Data from the limbs are then analysed to identify, to which limb movement signifies which sources of difficulty (i.e. reach, visibility, etc.) in assembly; for example reach difficulty is indicated by torso movement. Finally, the thesis proposes as a part of the future work in possible improvement of the assessment method. Also, its application using a virtual reality (VR) platform assesses in ascertaining ease or difficulties in assembly and many.
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Reconnaissance d'activités humaines à partir de séquences multi-caméras : application à la détection de chute de personne / Recognition of human activities based on multi-camera sequences : application to people fall detectionMousse, Ange Mikaël 10 December 2016 (has links)
La vision artificielle est un domaine de recherche en pleine évolution. Les nouvelles stratégies permettent d'avoir des réseaux de caméras intelligentes. Cela induit le développement de beaucoup d'applications de surveillance automatique via les caméras. Les travaux développés dans cette thèse concernent la mise en place d'un système de vidéosurveillance intelligente pour la détection de chutes en temps réel. La première partie de nos travaux consiste à pouvoir estimer de façon robuste la surface d'une personne à partir de deux (02) caméras ayant des vues complémentaires. Cette estimation est issue de la détection de chaque caméra. Dans l'optique d'avoir une détection robuste, nous avons fait recours à deux approches. La première approche consiste à combiner un algorithme de détection de mouvements basé sur la modélisation de l'arrière plan avec un algorithme de détection de contours. Une approche de fusion a été proposée pour rendre beaucoup plus efficiente le résultat de la détection. La seconde approche est basée sur les régions homogènes de l'image. Une première ségmentation est effectuée dans le but de déterminer les régions homogènes de l'image. Et pour finir, nous faisons la modélisation de l'arrière plan en se basant sur les régions. Une fois les pixels de premier plan obtenu, nous faisons une approximation par un polygone dans le but de réduire le nombre d'informations à manipuler. Pour l'estimation de cette surface nous avons proposé une stratégie de fusion dans le but d'agréger les détections des caméras. Cette stratégie conduit à déterminer l'intersection de la projection des divers polygones dans le plan de masse. La projection est basée sur les principes de l'homographie planaire. Une fois l'estimation obtenue, nous avons proposé une stratégie pour détecter les chutes de personnes. Notre approche permet aussi d'avoir une information précise sur les différentes postures de l'individu. Les divers algorithmes proposés ont été implémentés et testés sur des banques de données publiques dans le but de juger l'efficacité des approches proposées par rapport aux approches existantes dans l'état de l'art. Les résultats obtenus et qui ont été détaillés dans le présent manuscrit montrent l'apport de nos algorithmes. / Artificial vision is an involving field of research. The new strategies make it possible to have some autonomous networks of cameras. This leads to the development of many automatic surveillance applications using the cameras. The work developed in this thesis concerns the setting up of an intelligent video surveillance system for real-time people fall detection. The first part of our work consists of a robust estimation of the surface area of a person from two (02) cameras with complementary views. This estimation is based on the detection of each camera. In order to have a robust detection, we propose two approaches. The first approach consists in combining a motion detection algorithm based on the background modeling with an edge detection algorithm. A fusion approach has been proposed to make much more efficient the results of the detection. The second approach is based on the homogeneous regions of the image. A first segmentation is performed to find homogeneous regions of the image. And finally we model the background using obtained regions.
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Comportamento social e territorialidade alimentar na gar?a-azul, Egretta caerulea (L) = Feeding territoriality in the little blue heron, Egretta caerulea (L)Silva, Emmanuel Moralez da 28 March 2008 (has links)
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Previous issue date: 2008-03-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The use of habitat is an important part of a species biology. One resource of great importance for the survivor and reproduction of an individual is the food resource. Thus, the
social interactions an animal has during the feeding activities are of extremely importance within its behavioral aspects, which represents the part of an organism trough which it
interacts with the environment, adapting to changes and variations. Herons are known to form feeding aggregations of even more than thousands of individuals, in which social components of foraging have been identified and studied for several species. More profound studies of these aspects are yet to poor for the Little Blue Heron, Egretta caerulea. Therefore, the aim of this study was to describe the social behavior (display postures, vocalizations and co-specific
interactions) and the territoriality of the specie during the feeding period in an area of mud bank in the estuarine system of Canan?ia, south coast of S?o Paulo state, Brazil. The defense of a fixed and exclusive area, closest to the mangrove, trough expulsion was observed; some
thing that have not yet been registered with concrete data for the specie. Higher capture and success rates, and lower investment rates (steps/min and stabs/min) were registered for individuals foraging in areas corresponding to the defended territory. This could be one of possible reasons for the establishment of territories in the area. Four display postures were registered for the specie, two of then new in the literature, which are used in the interactions between individuals; one vocalization, that apparently is important in the social context of foraging for the specie and, possibly, has a function of advertising and proclaiming the dominance position of the territorial individual within the group. A territorial individual uses three behaviors, of the ones described: expulsion, vocalization and encounter (agonistic
encounter between individuals, without physical aggression). Of these, the expulsion is apparently used in the actual defense, actively; while the other two behaviors are used in a
more passive way, in the maintenance of the dominance position of the individual, helping it in the defense of its territory in a less direct manner. Therefore, with the results presented in here, new components of the social utilization of the feeding resource for the Little Blue Heron were identified, incorporating aspects of the territorial behavior for a future
understanding of its possible adaptive significance. And it also reinforces the importance of the social interactions of herons foraging in great aggregations, in areas ecologically important / A utiliza??o do habitat ? parte importante da biologia de uma esp?cie. Um dos recursos importantes para a sobreviv?ncia e reprodu??o de um indiv?duo ? o recurso alimentar. Desta forma, as intera??es sociais que um animal mant?m durante as atividades de forrageio s?o de suma import?ncia dentre seus aspectos comportamentais, os quais, por sua
vez, representam a parte de um organismo atrav?s da qual este interage com o ambiente, adaptando-se as varia??es e mudan?as no meio. Gar?as s?o conhecidas por formar agrega??es alimentares que podem conter at? milhares de indiv?duos, nas quais componentes sociais do forrageio t?m sido identificados e estudados para v?rias esp?cies. Estudos mais aprofundados destes aspectos ainda s?o escassos para a gar?a-azul, Egretta caerulea. Desta forma, o objetivo deste estudo foi descrever o comportamento social (posturas de exibi??o, vocaliza??es e intera??es co-espec?ficas) e a territorialidade da esp?cie durante o per?odo de forrageio em uma ?rea de baixio lodoso no sistema estuarino de Canan?ia, litoral sul do estado de S?o Paulo, Brasil. Observou-se a defesa de uma ?rea fixa e exclusiva, pr?xima ao manguezal, atrav?s da expuls?o; algo que ainda n?o tinha sido registrado com dados concretos para a esp?cie. Registraram-se taxas de captura e sucesso maiores para indiv?duos forrageando
na ?rea correspondente ao territ?rio defendido, assim como menores taxas de investimento no forrageio. Desta forma, esta pode ser uma das raz?es pelo estabelecimento de territ?rios pela esp?cie no local. Registraram-se quatro posturas de exibi??o para a esp?cie, das quais duas
s?o novas na literatura e s?o utilizadas nas intera??es entre indiv?duos. Registrou-se uma vocaliza??o, que aparentemente ? importante no contexto social do forrageio para a esp?cie e,
possivelmente, tem fun??o de advert?ncia e proclama??o da posi??o de domin?ncia ocupada pelo indiv?duo territorial dentro do grupo. Um indiv?duo territorial utiliza-se de tr?s
comportamentos, dos descritos: expuls?o, vocaliza??o e encontro (encontro agon?stico entre indiv?duos, sem agress?o f?sica). Destes, aparentemente a expuls?o ? utilizada na defesa ativa; enquanto que os outros dois comportamentos s?o utilizados de uma forma mais passiva, na manuten??o da posi??o de domin?ncia do indiv?duo, ajudando-o na defesa de seu territ?rio de uma forma menos direta. Assim, com os resultados apresentados neste trabalho, identificaram-se novos componentes do comportamento social da utiliza??o do recurso alimentar pela gar?a-azul, incorporando-se aspectos do comportamento territorial para um futuro entendimento de sua poss?vel signific?ncia adaptativa. Refor?a-se tamb?m a
import?ncia das intera??es sociais de gar?as que forrageiam em agregados contendo milhares de indiv?duos, em ?reas ecologicamente importantes
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