58 research outputs found

    View recommendation for multi-camera demonstration-based training

    Get PDF
    While humans can effortlessly pick a view from multiple streams, automatically choosing the best view is a challenge. Choosing the best view from multi-camera streams poses a problem regarding which objective metrics should be considered. Existing works on view selection lack consensus about which metrics should be considered to select the best view. The literature on view selection describes diverse possible metrics. And strategies such as information-theoretic, instructional design, or aesthetics-motivated fail to incorporate all approaches. In this work, we postulate a strategy incorporating information-theoretic and instructional design-based objective metrics to select the best view from a set of views. Traditionally, information-theoretic measures have been used to find the goodness of a view, such as in 3D rendering. We adapted a similar measure known as the viewpoint entropy for real-world 2D images. Additionally, we incorporated similarity penalization to get a more accurate measure of the entropy of a view, which is one of the metrics for the best view selection. Since the choice of the best view is domain-dependent, we chose demonstration-based training scenarios as our use case. The limitation of our chosen scenarios is that they do not include collaborative training and solely feature a single trainer. To incorporate instructional design considerations, we included the trainer’s body pose, face, face when instructing, and hands visibility as metrics. To incorporate domain knowledge we included predetermined regions’ visibility as another metric. All of those metrics are taken into account to produce a parameterized view recommendation approach for demonstration-based training. An online study using recorded multi-camera video streams from a simulation environment was used to validate those metrics. Furthermore, the responses from the online study were used to optimize the view recommendation performance with a normalized discounted cumulative gain (NDCG) value of 0.912, which shows good performance with respect to matching user choices

    Personalising Vibrotactile Displays through Perceptual Sensitivity Adjustment

    Get PDF
    Haptic displays are commonly limited to transmitting a discrete set of tactile motives. In this paper, we explore the transmission of real-valued information through vibrotactile displays. We simulate spatial continuity with three perceptual models commonly used to create phantom sensations: the linear, logarithmic and power model. We show that these generic models lead to limited decoding precision, and propose a method for model personalization adjusting to idiosyncratic and spatial variations in perceptual sensitivity. We evaluate this approach using two haptic display layouts: circular, worn around the wrist and the upper arm, and straight, worn along the forearm. Results of a user study measuring continuous value decoding precision show that users were able to decode continuous values with relatively high accuracy (4.4% mean error), circular layouts performed particularly well, and personalisation through sensitivity adjustment increased decoding precision

    Linked data query wizard: A novel interface for accessing sparql endpoints

    Get PDF
    In an interconnected world, Linked Data is more important than ever before. However, it is still quite difficult to access this new wealth of semantic data directly without having in-depth knowledge about SPARQL and related semantic technologies. Also, most people are currently used to con-suming data as 2-dimensional tables. Linked Data is by defi-nition always a graph, and not that many people are used to handle data in graph structures. Therefore we present the Linked Data Query Wizard, a web-based tool for displaying, accessing, filtering, exploring, and navigating Linked Data stored in SPARQL endpoints. The main innovation of the interface is that it turns the graph structure of Linked Data into a tabular interface and provides easy-to-use interaction possibilities by using metaphors and techniques from current search engines and spreadsheet applications that regular web users are already familiar with

    A study on labeling network hostile behavior with Intelligent Interactive tools

    Get PDF
    Labeling a real network dataset is specially expensive in computersecurity, as an expert has to ponder several factors before assigningeach label. This paper describes an interactive intelligent systemto support the task of identifying hostile behaviors in network logs.The RiskID application uses visualizations to graphically encodefeatures of network connections and promote visual comparison. Inthe background, two algorithms are used to actively organize con-nections and predict potential labels: a recommendation algorithmand a semi-supervised learning strategy. These algorithms togetherwith interactive adaptions to the user interface constitute a behaviorrecommendation. A study is carried out to analyze how the algo-rithms for recommendation and prediction influence the workflowof labeling a dataset. The results of a study with 16 participantsindicate that the behaviour recommendation significantly improvesthe quality of labels. Analyzing interaction patterns, we identify amore intuitive workflow used when behaviour recommendation isavailable.Fil: Guerra Torres, Jorge Luis. Universidad Nacional de Cuyo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Veas, Eduardo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Catania, Carlos Adrian. Universidad Nacional de Cuyo; Argentina2019 IEEE Symposium on Visualization for Cyber SecurityVancouverCanadáInstitute of Electrical and Electronics Engineer

    Nuevas determinantes para comprender los alcances de la ruralidad: representaciones del cambio climático en la agricultura familiar campesina

    Get PDF
    Currently the rural territories represent a major challenge for decision makers and academics, specially concerning to the analysis and the planification strategies. Regarding to Chile, the lack of planification instruments, the economic system pressure and the sociodemographic configuration changes make a shared definition of rurality imperative. Rural areas in Chile, specifically those with an agricultural vocation, have undergone profound transformations in recent decades, generated mainly by the agro-export economic model and the consequent liberalization in the use of agricultural land, leading to both, environmental degradation and transformation of livelihoods. To this the environmental changes associated with climate change, are imposing the farmers to reanalyze the production systems and the territory linkage. This study contributes to the understanding of the interaction that take place in rural areas, analyzing them from the perspective of the evolution of agricultural practices associated with climate change scenarios. Data were collected through the application of semi-structured surveys to a group of farmers concerning their climate change understanding representations and the strategies that they aredeveloping to address it. The results give account of an incidence of environmental disturbance associated with the climate change, for example water scarcity or changes in temperature regimes over several parameters, such as the local agricultural practices, the relationships between actors and development strategies. In addition to farmers' perceptions have on climate change, the redefinition of the productive system would explain the changes transformations in their relationship with other actors and with their own territory.Los territorios rurales constituyen hoy en día, en términos de análisis y planificación, un gran desafío tanto para los tomadores de decisiones como académicos. En el caso de Chile, la falta de instrumentos de planificación, la presión de actividades económicas y las transformaciones de la configuración sociodemográfica hacen urgente una definición compartida de la ruralidad. Los espacios rurales en Chile, específicamente los de vocación agrícola, han experimentado durante las últimas décadas profundas transformaciones generadas principalmente por el modelo económico agroexportador y la consiguiente liberalización en el usufructo de los terrenos agrícolas, conllevando a su vez a un deterioro medioambiental y a una transformación de los medios de vida. A esto se adicionan los cambios ambientales asociados al cambio climático, imponiéndole a los agricultores repensar los sistemas de producción y las relaciones con el territorio. El objetivo de este artículo es contribuir en la comprensión de las interacciones que se dan a lugar en las áreasrurales, analizándolas desde la perspectiva de la evolución de las prácticas agrícolas frente a variables ambientales asociados al cambio climático. Los datos fueron recolectados a través de la aplicación de encuestas semiestructuradas a un grupo de productores sobre las representaciones que ellos tienen del cambio climático y las estrategias que desarrollan para enfrentarlo. Los resultados dan cuenta de una incidencia de forzantes ambientales asociados al cambio climático, como la escasez hídrica o cambios en los regímenes de temperaturas, sobre las prácticas agrícolas locales, las relaciones entre actores y las estrategias de desarrollo. La redefinición de los sistemas de producción da cuenta, además de las percepciones que los agricultores tienen del cambio climático, de las transformaciones en las formas de relacionarse con otros actores y con su propio territorio

    A Study on User-Controllable Social Exploratory Search

    Get PDF
    Information-seeking tasks with learning or investigative purposes are usually referred to as exploratory search. Exploratory search unfolds as a dynamic process where the user, amidst navigation, trial-and-error and on-the-fly selections, gathers and organizes information (resources). A range of innovative interfaces with increased user control have been developed to support exploratory search process. In this work we present our attempt to increase the power of exploratory search interfaces by using ideas of social search, i.e., leveraging information left by past users of information systems. Social search technologies are highly popular nowadays, especially for improving ranking. However, current approaches to social ranking do not allow users to decide to what extent social information should be taken into account for result ranking. This paper presents an interface that integrates social search functionality into an exploratory search system in a user-controlled way that is consistent with the nature of exploratory search. The interface incorporates control features that allow the user to (i) express information needs by selecting keywords and (ii) to express preferences for incorporating social wisdom based on tag matching and user similarity. The interface promotes search transparency through color-coded stacked bars and rich tooltips. In an online study investigating system accuracy and subjective aspects with a structural model we found that, when users actively interacted with all its control features, the hybrid system outperformed a baseline content-based-only tool and users were more satisfied

    Persistent Sepsis-Induced Hypotension without Hyperlactatemia: A Distinct Clinical and Physiological Profile within the Spectrum of Septic Shock

    Get PDF
    Introduction. A subgroup of septic shock patients will never develop hyperlactatemia despite being subjected to a massive circulatory stress. Maintenance of normal lactate levels during septic shock is of great clinical and physiological interest. Our aim was to describe the clinical, hemodynamic, perfusion, and microcirculatory profiles associated to the absence of hyperlactatemia during septic shock resuscitation. Methods. We conducted an observational study in septic shock patients undergoing resuscitation. Serial clinical, hemodynamic, and perfusion parameters were registered. A single sublingual microcirculatory assessment was performed in a subgroup. Patients evolving with versus without hyperlactatemia were compared. Results. 124 septic shock patients were included. Patients without hyperlactatemia exhibited lower severity scores and mortality. They also presented higher platelet counts and required less intensive treatment. Microcirculation was assessed in 45 patients. Patients without hyperlactatemia presented higher PPV and MFI values. Lactate was correlated to several microcirculatory parameters. No difference in systemic flow parameters was observed. Conclusion. Persistent sepsis-induced hypotension without hyperlactatemia is associated with less organ dysfunctions and a very low mortality risk. Patients without hyperlactatemia exhibit less coagulation and microcirculatory derangements despite comparable macrohemodynamics. Our study supports the notion that persistent sepsis-induced hypotension without hyperlactatemia exhibits a distinctive clinical and physiological profile

    Efecto del tamaño de tamiz en la caracterización de la macrofauna marina bentónica: Implicancias para su uso en líneas de base, caracterizaciones preliminares de sitios para la acuicultura y monitoreos ambientales en Chile

    Get PDF
    Las características ecológicas de la macrofauna bentónica, la convierten en un buen indicador para evaluar los efectos de perturbaciones antropogénicas (e.g., acuicultura, emisarios submarinos, etc.) sobre los ecosistemas marinos. La normativa chilena aplicable a monitoreos ambientales establece que su caracterización debe realizarse utilizando tamices de 1.000 µm de abertura. Con el objetivo de evaluar la pérdida de información en composición y abundancia de las especies al utilizar este tamiz respecto de uno de 500 µm, se realizaron muestreos submareales en invierno y verano del 2018 en 5 áreas del Golfo de Arauco, Chile central. El muestreo y análisis consistió en: (i) cernido en tamiz de 1.000 µm, reteniendo los organismos que traspasan este tamiz en uno de 500 µm, (ii) identificación de los organismos retenidos en ambos tamices hasta el nivel taxonómico más bajo posible y, (iii) comparación de la macrofauna entre tamices, períodos y áreas de muestreo, utilizando estadística univariada y multivariada. A partir de los análisis se encontraron diferencias significativas en la estructura comunitaria de la macrofauna entre tamices, áreas y periodos de muestreo. Los índices AMBI y W, utilizados como bio-indicadores comunitarios, también identifican diferencias significativas entre tamices. Los resultados señalan que, si bien el uso de un tamiz de 1.000 µm permite identificar diferencias espaciales y temporales en la macrofauna, con su uso se subestima el nivel de impacto detectado por los bio-indicadores comunitarios. Por tal razón, se recomienda utilizar un tamiz de 500 µm si el objetivo es evaluar impactos antropogénicos en el ambiente marino, especialmente en líneas de base, caracterizaciones preliminares de sitio para la acuicultura y programas de vigilancia ambiental. Toda la información, debiera, además, ser integrada mediante herramientas estadísticas multivariadas, capaces de incorporar en conjunto los antecedentes biológicos y ambientales recopilados en el área de estudio
    corecore