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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.
111

XSiena: The Content-Based Publish/Subscribe System

Jerzak, Zbigniew 28 September 2009 (has links)
Just as packet switched networks constituted a major breakthrough in our perception of the information exchange in computer networks so have the decoupling properties of publish/subscribe systems revolutionized the way we look at networking in the context of large scale distributed systems. The decoupling of the components of publish/subscribe systems in time, space and synchronization has created an appealing platform for the asynchronous information exchange among anonymous information producers and consumers. Moreover, the content-based nature of publish/subscribe systems provides a great degree of flexibility and expressiveness as far as construction of data flows is considered. However, a number of challenges and not yet addressed issued still exists in the area of the publish/subscribe systems. One active area of research is directed toward the problem of the efficient content delivery in the content-based publish/subscribe networks. Routing of the information based on the information itself, instead of the explicit source and destination addresses poses challenges as far as efficiency and processing times are concerned. Simultaneously, due to their decoupled nature, publish/subscribe systems introduce new challenges with respect to issues related to dependability and fail-awareness. This thesis seeks to advance the field of research in both directions. First it shows the design and implementation of routing algorithms based on the end-to-end systems design principle. Proposed routing algorithms obsolete the need to perform content-based routing within the publish/subscribe network, pushing this task to the edge of the system. Moreover, this thesis presents a fail-aware approach towards construction of the content-based publish/subscribe system along with its application to the creation of the soft state publish/subscribe system. A soft state publish/subscribe system exposes the self stabilizing behavior as far as transient timing, link and node failures are concerned. The result of this thesis is a family of the XSiena content-based publish/subscribe systems, implementing the proposed concepts and algorithms. The family of the XSiena content-based publish/subscribe systems has been a subject to rigorous evaluation, which confirms the claims made in this thesis.
112

The Effects of Caffeine Gum Administration on Reaction Time and Lower Body Pain During Cycling to Exhaustion

Jankowski-Wilkinson, Andrea Faye 02 September 2008 (has links)
No description available.
113

Framtidens trygghetslarm : Ett självständighetsfrämjande produkt-tjänstesystem / The future medical alert system : An independence promoting product service system

Bäcknäs, Annie, Laudon, Siri January 2018 (has links)
Genom en användarcentrerad produktutvecklingsprocess har ett framtidskoncept förtrygghetslarm utvecklats. Det framtagna trygghetslarmet ämnar stärka användarenssjälvständighet genom ett preventivt, istället för enbart reaktivt arbete.Det preventiva arbetet inleds genom att larmet introduceras i ett tidigare skede för att med hjälpav sensorer och Artificiell Intelligens förebygga åldersrelaterade sjukdomar. Genom tidigimplementering finns larmet också till hands redan innan olyckan inträffat.Syftet med projektet var att med ett tjänstedesign-perspektiv undersöka vad som skapar trygghetför användaren samt hur det stödjs i en produkt och tjänst. Under arbetet trädde en komplexbehovsbild fram som skiftade, inte bara mellan användare, utan även för den enskildeanvändaren över tid. Därför skapades ett modulbaserat produkt-tjänstesystem som innefattar treproduktvarianter som tillsammans tillgodoser de allra flesta användarnas behov.Ett tjänstebaserat trygghetslarm med möjlighet till uppgraderingar, byten och reparationerinnebär i längden en högre konkurrenskraft och en mer hållbar modell där användarens ochvårdbolagens behov bättre tillgodoses. En tjänst som bygger på en applikationsbaseradplattform kan anpassas för användaren och tillgängliggöra relevant information för att minskadet utanförskap som många användare upplever.Genom en iterativ process av interaktioner, insikter och konceptgenerering bidrogtjänstedesignperspektivet med en behovsbaserad analys. Produkt-tjänstesystemets utformningär baserat på insikter som erhölls under kontextuella intervjuer. Intervjuerna involverade olikaaktörer såsom vårdgivare, teknikbolag och forskare men främst dagens och den kommandegenerationens användare. Syftet var att skapa ett brett underlag som bidrar till en holistisk bildav användarens behov.Vid interaktioner framkom att larmet måste vara mobilt och kunna ange position. Mobilitetbidrar till ett tryggt aktivt liv utanför hemmet. Att hålla sig fysiskt och socialt aktiv menar WorldHealth Organisation, WHO, är grunden för ett självständigt och hälsosamt åldrande som är enförutsättning för att kunna möta utmaningarna med en åldrande befolkning.För att attrahera användare måste associationerna kring trygghetslarmet förskjutas frånhjälplöshet till självständighet, aktivitet och välbefinnande. Genom att tidigt introducera larmetsom ett hälsofrämjande verktyg kan det arbeta preventivt. Med hjälp av AI, rörelse- ochpulssensor kan exempelvis förmaksflimmer upptäckas och behandlas innan det leder till stroke.I kombination med inbyggd fallsensor kan larm skickas automatiskt vid behov. Integreradtelefoni skapar trygghet genom förbättrad kommunikation.Kombinationen av modulär produktutveckling, produkt-tjänstesystem och cirkulär ekonomierbjuder ett mer hållbart produktsystem som leder till starkare konkurrenskraft, bättreindividanpassning och längre hållbarhet. Det vore önskvärt om aktörer inom trygghetslarmuppdaterade sina affärsmodeller för att erbjuda nya ägarmodeller. Vårdbolag skulle ges störremöjlighet att erbjuda den senaste tekniken och skulle inte dras med föråldrad teknik på grundav tidigare gjorda investeringar, vilket skulle innebära en säkrare och tryggare vård. / Through a user-centered product development process, a future concept for medical alertsystems has been developed. The developed medical alert system aims to strengthen the user'sindependence through preventive, rather than reactive work.The preventive work is initiated by the early implementation of the alarm to prevent agerelateddiseases using sensors and Artificial Intelligence. By early implementation, the alarmis also available even before the accident occur.The purpose of the project was to investigate what creates safety for the user and how it issupported in a product and service with a service design perspective. During the work, acomplex image of the users needs emerged that changed, not only between users, but also forthe individual user over time. Therefore, a modular product service system was created thatincludes three product variants that together meet the needs of most users.A service-based medical alert system with the possibility of upgrades, replacements and repairsmeans long-term competitiveness and a more sustainable model that better meet the needs ofthe user and healthcare companies. A service based on an application-based platform can becustomized to the user and make relevant information available to reduce the exclusion thatmany users experience.Through an iterative process of interactions, insights and concept generation, the service designperspective contributed with a needs-based analysis. The design of the product service systemis based on insights obtained during contextual interviews. The interviews involved differentactors such as healthcare providers, technology companies and researchers, but mainly oftoday's and next-generation users. The purpose was to create a broad basis that contributes to aholistic view of the user´s need.Through interactions it was found that the alarm must be mobile and be able to share its position.Mobility contributes to a safe active life outside the home. Keeping physically and sociallyactive is according to the World Health Organization, WHO, the foundation for independentand healthy aging and is a prerequisite for meeting the challenges of an aging population.To attract users, the association to the medical alert system must be shifted from helplessnessto independence, activity and well-being. By introducing the alarm early as a health-promotingtool, it can work preventively. For example, by means of AI, motion and pulse sensors, atrialfibrillation can be detected and treated before it leads to stroke. In combination with the builtinfall sensor, alarms can be sent automatically when needed. Integrated telephony createssecurity through much improved communication.The combination of modular product development, product service systems and circulareconomy offers a more sustainable product system, that leads to greater competitiveness, betterindividualization and longer durability. It would be desirable for actors within medical alertsystems to update their business models to offer new ownership models. The healthcarecompanies would have a greater opportunity to offer the latest technology and would not bebound to outdated technology due to previously made investments, which would mean a saferand more secure elderly care.
114

ENHANCING ACTIVE WORK ZONE SAFETY WITH INTRUSION ALERT TECHNOLOGIES: EMPIRICAL EVIDENCE ON EFFECTIVENESS AND IMPLICATIONS

Hrishikesh Suresh Pokharkar (14221811) 15 December 2022 (has links)
<p>  </p> <p>Highway workers are required to work close to moving traffic during road construction and maintenance activities, which exposes them to the risk of being struck by a distracted driver or intruding vehicle. In addition, work zones disturb the usual traffic flow and patterns due to changes in the existing geometric layout of a roadway, and this is also problematic for the drivers as they must navigate a layout of signs, barrels, and lane changes while keeping the vehicle in control. Moreover, late-night tasks, reckless driving, inconsistent work zones, drunk driving, and increased vehicle miles traveled are some of the additional causes of work zone incidents in the United States. Nationwide, around 40,000 accidents occur each year in highway work zones due to vehicle intrusion into the work zone and have steadily increased during the past ten years. Most often, the driver and passenger of the vehicle are the victims of such accidents. The resulting fatalities, injuries, and property damage due to such incidents lead to significant expenses, prolonged travel delays, and potential damage to expensive products in transit.</p> <p>While traditional safety precautions (e.g., truck-mounted attenuators, rumble strips, speed monitoring displays) can help enhance work zone safety, the number of work zone intrusions calls for designing and implementing emerging intrusion alert technologies to warn drivers and workers when errant vehicles intrude into the work zone. Several state Departments of Transportation (DOTs) have begun examining the use of intrusion alert technologies to mitigate work zone intrusions. While previous studies examined the general effectiveness (e.g., sound levels, work zone coverage, deployment characteristics, etc.) of these technologies in both controlled and active construction and maintenance work zones, there are still significant research gaps in investigating how well these intrusion technologies alert the driver and workers, and no documented best practices are available for transportation agencies and DOTs interested in implementing them. In addition, these technologies have been through many improvements and modifications, and further research is imperative to ascertain their chances of acceptance by workers and contractors.</p> <p>To address these gaps, this thesis focuses on (a) empirically examining the effectiveness, implications, and practices of four commercially available intrusion technologies in enhancing work zone safety through various field tests and surveys, and (b) empirically investigating the effectiveness of these technologies considering drivers’ cognitive processing (perception -reaction time) and responses in case of work zone intrusion. The findings of this research study provide detailed information on the identification and testing procedures of technologies and offer guidelines and recommendations for adopting these technologies for practitioners and professionals in the highway construction sector. The proposed decision-making matrix and multi-criteria decision-making framework are based on the empirical data obtained from the various field experiments, literature review, and evaluation survey. This study also provides valuable insights into the overall effectiveness (i.e., by considering functional characteristics, associated drivers’ responses and reactions, and current implementation) of commercially available intrusion technologies to incorporate required modifications in designing and implementing these technologies to enhance work zone safety. The long-term outcome of this study is to significantly reduce the injuries and fatalities in highway maintenance work zones in Indiana and across the country.</p>
115

Directive Displays: Supporting Human-machine Coordination by Dynamically Varying Representation, Information, and Interjection Strength

Rayo, Michael F., Jr 03 September 2013 (has links)
No description available.
116

Thrombolytic therapy in acute myocardial infarction - the specific barriers related to `time' delays in the door to needle time at the Al Ain hospital

Pillay, Vathaniagee 31 March 2005 (has links)
This study addresses the specific barriers related to time delays in the treatment of patients who suffered acute myocardial infarction at the Al Ain Hospital accident and emergency unit in the United Arab Emirates. A comprehensive background of the UAE is given for the benefit of students who have limited access to the background and challenges facing medical and nursing personnel in providing thrombolythic therapy to patients who suffered from acute myocardial infarction. The study will contribute to the continuous quality management and improvement of overall nursing and medical care of the AMI patient who is eligible for thrombolysis. An extensive literature review addresses the clinical manifestations and treatment of the patient suffering from AMI as well as the adverse effects of time delays in treatment during the acute phase of the disease. The researcher selected a quantitative, non-experimental descriptive and retrospective study. Data was collected by a structured instrument to gather the desired responses from the files of 457 selected patients admitted to the Al Ain Hospital. This study emphasizes the need to improve patient care by all health care personnel in an accident and emergency unit to prevent the delays in treatment in life threatening conditions such as myocardial infarction ensuring optimal and prompt time to thrombolyse. The improvement of awareness and commitment by health care providers such as nurses, doctors and ambulance personnel, can be achieved through education and training, commitment and dedication, absolute cooperation, collaboration and constant update on performance. Regular audits are essential with regard to door-to-needle time and performance of all health care providers. This study ultimately show that time constrains in attending to patients presenting with myocardial infarction should be addressed in utmost urgency. / Health Studies / M. A. (Health Studies)
117

Réflexion sur l'abus en droit des sociétés dans l'espace Ohada : contribution du droit français / Reflection on the abuse in corporate law : contribution of French law

Aguemon, Khaled 07 September 2013 (has links)
Depuis des lustres, les sociétés commerciales n’ont cessé d’être l’accessoire juridique favori des entrepreneurs dans l’exercice de leur activité. La société commerciale est créée par deux ou plusieurs personnes qui conviennent, par un contrat, d’affecter à une activité des biens en numéraire ou en nature, dans le but de partager le bénéfice ou de profiter de l’économie qui pourra en résulter. Cette définition découle de l’article 4 de l’AUSCGIE qui constitue une transposition de l’article 1832 du Code civil. L’AUSCGIE rassemble toutes les normes juridiques qui ont pour objectif de gouverner la constitution, l’activité et la fin de la société. Une des prérogatives les plus importantes des associés est de prendre part à la vie sociale, ils peuvent participer à cette vie sociale en dirigeant la société ou de façon plus réservée, en votant dans les différentes assemblées. Toutefois ce droit, comme tout droit est susceptible d’abus ; l’abus étant un usage injustifié ou excessif de quelque chose ou d’un pouvoir par son titulaire. D’un point de vue impartial avec les autres associés, l’AUSCGIE a codifié dans ses dispositions des sanctions contre les abus commis à l’occasion de l’exercice du droit de vote. Toutefois, l’abus ne se révèle pas uniquement lors de l’exercice du droit de vote. De multiples abus se révèlent aussi dans la direction et la gestion d’une société. Là encore, l’AUSCGIE a prévu des dispositions et laissé le soin aux Etats-parties d’instaurer dans leur législation des lois pour sanctionner ces abus. Le concept d’abus nous pousse donc à étudier les sources de sanction de ce dernier dans l’espace Ohada. / For decades, corporations have ceased to be legal accessory favorite of contractors in the exercise of their activity. The corporation is created by two or more persons who agree, by contract, to assign an activity assets in cash or in kind, to share in the profit or advantage of the savings that may result. This definition follows from Article 4 of the AUSCGIE which is transposition of Article 1832 of the Civil Code. AUSCGIE gathers all the legal standards that are intended to govern the establishment, activity and the end of the company. One of the most important partners prerogatives is to take part in social life, they can participate in the social life by directing the company or more reserved, by voting in the various assemblies. However, this law, like any law is open to abuse; abuse is unjustified or excessive use of something or power by its owner. From an impartial point of view with the other partners AUSCGIE codified in his texts sanctions against abuses in connection with the exercise of voting rights. However, abuse is not revealed only when the right to vote. Many abuses also reveal the direction and management of a company. Again, AUSCGIE provided texts and left it to the States Parties to introduce in their legislation laws against such abuses. The concept of abuse leads us to study the sources of sanction it in OHADA space.
118

Adaptive Eyes

Wege, Claudia 10 April 2015 (has links) (PDF)
Technology pervades our daily living, and is increasingly integrated into the vehicle – directly affecting driving. On the one hand technology such as cell phones provoke driver distraction and inattention, whereas, on the other hand, Advanced Driver Assistance Systems (ADAS) support the driver in the driving task. The question is, can a driver successfully adapt to the ever growing technological advancements? Thus, this thesis aimed at improving safe driver behaviour by understanding the underlying psychological mechanisms that influence behavioural change. Previous research on ADAS and human attention was reviewed in the context of driver behavioural adaptation. Empirical data from multiple data sources such as driving performance data, visual behaviour data, video footage, and subjective data were analyzed to evaluate two ADAS (a brake-capacity forward collision warning system, B-FCW, and a Visual Distraction Alert System, VDA-System). Results from a field operational test (EuroFOT) showed that brake-capacity forward collision warnings lead to immediate attention allocation toward the roadway and drivers hit the brake, yet change their initial response later on by directing their eyes toward the warning source in the instrument cluster. A similar phenomenon of drivers changing initial behaviour was found in a driving simulator study assessing a Visual Distraction Alert System. Analysis showed that a Visual Distraction Alert System successfully assists drivers in redirecting attention to the relevant aspects of the driving task and significantly improves driving performance. The effects are discussed with regard to behavioural adaptation, calibration and system acceptance. Based on these findings a novel assessment for human-machine-interaction (HMI) of ADAS was introduced. Based on the contribution of this thesis and previous best-practices, a holistic safety management model on accident prevention strategies (before, during and after driving) was developed. The DO-IT BEST Feedback Model is a comprehensive feedback strategy including driver feedback at various time scales and therefore is expected to provide an added benefit for distraction and inattention prevention. The central contributions of this work are to advance research in the field of traffic psychology in the context of attention allocation strategies, and to improve the ability to design future safety systems with the human factor in focus. The thesis consists of the introduction of the conducted research, six publications in full text and a comprehensive conclusion of the publications. In brief this thesis intends to improve safe driver behaviour by understanding the underlying psychological mechanisms that influence behavioral change, thereby resulting in more attention allocation to the forward roadway, and improved vehicle control. / Technologie durchdringt unser tägliches Leben und ist zunehmend integriert in Fahrzeuge – das Resultat sind veränderte Anforderungen an Fahrzeugführer. Einerseits besteht die Gefahr, dass er durch die Bedienung innovativer Technologien (z.B. Mobiltelefone) unachtsam wird und visuell abgelenkt ist, andererseits kann die Nutzung von Fahrerassistenzsystemen die den Fahrer bei der Fahraufgabe unterstützten einen wertvollen Beitrag zur Fahrsicherheit bieten. Die steigende Aktualität beider Problematiken wirft die Frage auf: "Kann der Fahrer sich erfolgreich dem ständig wachsenden technologischen Fortschritt anpassen?" Das Ziel der vorliegenden Arbeit ist der Erkenntnisgewinn zur Verbesserung des Fahrverhaltens indem der Verhaltensänderungen zugrunde liegende psychologische Mechanismen untersucht werden. Eine Vielzahl an Literatur zu Fahrerassistenzsystemen und Aufmerksamkeitsverteilung wurde vor dem Hintergrund von Verhaltensanpassung der Fahrer recherchiert. Daten mehrerer empirischer Quellen, z. B. Fahrverhalten, Blickbewegungen, Videomitschnitte und subjektive Daten dienten zur Datenauswertung zweier Fahrerassistenzsysteme. Im Rahmen einer Feldstudie zeigte sich, dass Bremskapazitäts-Kollisionswarnungen zur sofortigen visuellen Aufmerksamkeitsverteilung zur Fahrbahn und zum Bremsen führen, Fahrer allerdings ihre Reaktion anpassen indem sie zur Warnanzeige im Kombinationsinstrument schauen. Ein anderes Phänomen der Verhaltensanpassung wurde in einer Fahrsimulatorstudie zur Untersuchung eines Ablenkungswarnsystems, das dabei hilft die Blicke von Autofahrern stets auf die Straße zu lenken, gefunden. Diese Ergebnisse weisen nach, dass solch ein System unterstützt achtsamer zu sein und sicherer zu fahren. Die vorliegenden Befunde wurden im Zusammenhang zu Vorbefunden zur Verhaltensanpassung zu Fahrerassistenzsystemen, Fahrerkalibrierung und Akzeptanz von Technik diskutiert. Basierend auf den gewonnenen Erkenntnissen wurde ein neues Vorgehen zur Untersuchung von Mensch- Maschine-Interaktion eingeführt. Aufbauend auf den Resultaten der vorliegenden Arbeit wurde ein ganzheitliches Modell zur Fahrsicherheit und -management, das DO-IT BEST Feedback Modell, entwickelt. Das Modell bezieht sich auf multitemporale Fahrer-Feedbackstrategien und soll somit einen entscheidenen Beitrag zur Verkehrssicherheit und dem Umgang mit Fahrerunaufmerksamkeit leisten. Die zentralen Beiträge dieser Arbeit sind die Gewinnung neuer Erkenntnisse in den Bereichen der Angewandten Psychologie und der Verkehrspsychologie in den Kontexten der Aufmerksamkeitsverteilung und der Verbesserung der Gestaltung von Fahrerassistenzsystemen fokusierend auf den Bediener. Die Dissertation besteht aus einem Einleitungsteil, drei empirischen Beiträgen sowie drei Buchkapiteln und einer abschliessenden Zusammenfassung.
119

Thrombolytic therapy in acute myocardial infarction - the specific barriers related to `time' delays in the door to needle time at the Al Ain hospital

Pillay, Vathaniagee 31 March 2005 (has links)
This study addresses the specific barriers related to time delays in the treatment of patients who suffered acute myocardial infarction at the Al Ain Hospital accident and emergency unit in the United Arab Emirates. A comprehensive background of the UAE is given for the benefit of students who have limited access to the background and challenges facing medical and nursing personnel in providing thrombolythic therapy to patients who suffered from acute myocardial infarction. The study will contribute to the continuous quality management and improvement of overall nursing and medical care of the AMI patient who is eligible for thrombolysis. An extensive literature review addresses the clinical manifestations and treatment of the patient suffering from AMI as well as the adverse effects of time delays in treatment during the acute phase of the disease. The researcher selected a quantitative, non-experimental descriptive and retrospective study. Data was collected by a structured instrument to gather the desired responses from the files of 457 selected patients admitted to the Al Ain Hospital. This study emphasizes the need to improve patient care by all health care personnel in an accident and emergency unit to prevent the delays in treatment in life threatening conditions such as myocardial infarction ensuring optimal and prompt time to thrombolyse. The improvement of awareness and commitment by health care providers such as nurses, doctors and ambulance personnel, can be achieved through education and training, commitment and dedication, absolute cooperation, collaboration and constant update on performance. Regular audits are essential with regard to door-to-needle time and performance of all health care providers. This study ultimately show that time constrains in attending to patients presenting with myocardial infarction should be addressed in utmost urgency. / Health Studies / M. A. (Health Studies)
120

Escapando de predadores: múltiplas abordagens para a compreensão das decisões econômicas de fuga / Escaping from predators: multiple approaches to understanding the economic escape decisions

Samia, Diogo Soares Menezes 17 August 2015 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-06-15T18:33:41Z No. of bitstreams: 2 Tese - Diogo Soares Menezes Samia - 2015.pdf: 4976311 bytes, checksum: 317908c75deb4de1770cd68c544a5190 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-28T11:59:17Z (GMT) No. of bitstreams: 2 Tese - Diogo Soares Menezes Samia - 2015.pdf: 4976311 bytes, checksum: 317908c75deb4de1770cd68c544a5190 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Made available in DSpace on 2016-06-28T11:59:17Z (GMT). No. of bitstreams: 2 Tese - Diogo Soares Menezes Samia - 2015.pdf: 4976311 bytes, checksum: 317908c75deb4de1770cd68c544a5190 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) Previous issue date: 2015-08-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Optimal escape theory states that animals should counterbalance the costs and benefits of flight when escaping from a potential predator. However, in apparent contradiction with this well-established optimality model, birds and mammals generally initiate escape soon after beginning to monitor an approaching threat; a phenomena codified as the “Flush Early and Avoid the Rush” (FEAR) hypothesis. Typically, the FEAR hypothesis is tested using correlational statistics and is supported when there is a strong relationship between the distance at which an individual first responds behaviorally to an approaching predator (alert distance; AD), and its flight initiation distance (the distance at which it flees the approaching predator; FID). However, such correlational statistics are both inadequate to analyze relationships constrained by an envelope (such as that in the AD-FID relationship) and are sensitive to outliers with high leverage, which can lead one to erroneous conclusions. To overcome these statistical concerns we develop the phi index (Φ), a distribution-free metric to evaluate the goodness of fit of a 1:1 relationship in a constraint envelope (the prediction of the FEAR hypothesis). Using both simulation and empirical data, we conclude that Φ is superior to traditional correlational analyses because it explicitly tests the FEAR prediction, is robust to outliers, and it controls for the disproportionate influence of observations from large predictor values (caused by the constrained envelope in AD-FID relationship). Importantly, by analyzing the empirical data we corroborate the strong effect that alertness has on flight as stated by the FEAR hypothesis. / A teoria do escape ótimo afirma que os animais devem contrabalançar os custos e benefícios da fuga quando vão escapar de um predador. No entanto, em aparente contradição com este bem-estabelecido modelo ótimo, aves e mamíferos geralmente empreendem fuga logo após inicio do monitoramento do predador em potencial; um fenômeno denominado “Flush Early and Avoid the Rush hypothesis” (a hipótese FEAR). A hipótese FEAR é geralmente testada usando estatísticas correlativas e seu suporte se dá por uma forte relação positiva entre a distância na qual um indivíduo responde comportamentalmente a um predador que se aproxima (distância de alerta; alert distance, AD) e a distância do início da fuga (flight initiation distance, FID). No entanto, o uso de estatísticas correlativas para testar a hipótese FEAR pode levar a conclusões errôneas, já que estatísticas correlativas são inadequadas para análise de relações em envelope (tais como a relação entre AD e FID) e são sensíveis a valores discrepantes (outliers) com elevado efeito de alavancagem. Por isso, nós desenvolvemos o índice fi (Φ), uma métrica não-paramétrica destinada a avaliar a qualidade do ajuste de uma relação 1:1 restrita por um envelope (tal como a observada na hipótese FEAR). Usando simulações numéricas e dados empíricos, nós concluímos que Φ é uma métrica superior às análises de correlação tradicionais porque testa explicitamente a predição da hipótese FEAR, é robusta a outiliers, e ainda controla pela influência disproporcional dos altos de AD (causado pela relação em envelope entre AD e FID). Como predito pela hipótese FEAR, a análise dos dados empíricos corroborou o forte efeito que a distância de alerta tem sobre a decisão de fuga das presas.

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