1,348 research outputs found
Haptography: capturing the feel of real objects to enable authentic haptic rendering (invited paper)
Haptic interfaces are designed to allow humans to touch virtual objects as though they were real. Unfortunately, virtual surface models currently require extensive hand tuning and do not feel authentic, which limits the usefulness and applicability of such systems. The proposed approach of haptography seeks to address this deficiency by basing models on haptic data recorded from real interactions between a human and a target object. The studio haptographer uses a fully instrumented stylus to tap, press, and stroke an item in a controlled environment while a computer system records positions, orientations, velocities, accelerations, and forces. The point-and-touch haptographer carries a simply instrumented stylus around during daily life, using it to capture interesting haptic properties of items in the real world. Recorded data is distilled into a haptograph, the haptic impression of the object or surface patch, including properties such as local shape, stiffness, friction, and texture. Finally, the feel of the probed object is recreated via a haptic interface by accounting for the device\u27s natural dynamics and focusing on the feedback of high-frequency accelerations
Lifetime
Time is my bully. Time marks the start of something, as well as the end. We are all carrying out the inexorable passing of time as it relates to our impending mortalities.
I do not fear death.
The awareness of my body’s impermanence employs me to feel that much more connected to the vessel containing that of which I am.
But what am I? Am I my body- or is it much deeper?
Through the work executed during my graduate research, I have attempted to quantify my existence through the archiving my time and body. This document ushers you through my perception, my relationship to nature, and how it manifests through discovering answers to what I believe it means to be human
Measuring and explaining efficiency of different countries responses to Covid-19 pandemic : a conditional robust nonparametric approach
In this paper, we propose the use of a conditional nonparametric robust estimator to evaluate countries responses to the outburst of COVID-19 pandemic. We collect data for 105 countries (comprehending the initial period of pandemic through the end of may/2021), with variables regarding the death toll, economic indicators, demographic characteristics and non-pharmaceutical interventions. We create a novel framework for estimating efficiency of countries responses in more general terms than simply evaluating healthcare system performance. We use two distinct well-known second-stage approaches: regressing the conditional efficiency scores on the environmental variables, in order to compute measures of managerial efficiency to rank responses; and regressing the ratio of conditional and unconditional scores on conditioning factors, seeking to explore the relationship between non-pharmaceutical interventions and the estimated efficiencies. Our results indicate which countries and regions stood out for presenting efficient/inefficient responses and point to a negative relationship between the variables median age, average stringency index and average retail and recreation visitors change and efficiency estimates.O objetivo deste trabalho é propor a aplicação de um estimador não paramétrico para avaliar a eficiência das respostas dos paÃses à eclosão da pandemia de COVID-19. São coletados dados de 105 paÃses (compreendendo o perÃodo inicial da pandemia até o final de maio de 2021), com variáveis que englobam o número de mortos, indicadores econômicos, caracterÃsticas demográficas e intervenções não farmacológicas. Ao longo do texto são apresentadas as premissas utilizadas, que constituem um arcabouço inovador para estimar eficiência das respostas em termos mais gerais do que a simples avaliação da atuação do sistema de saúde. São implementadas duas técnicas de estimação em dois estágios, amplamente utilizadas na literatura: regressão dos scores de eficiência estimados contra as variáveis ambientais, com o objetivo de mensurar a eficiência gerencial e ranquear as respostas dos paÃses; e uma regressão das razões dos scores condicionais e não condicionais contra os fatores condicionantes, buscando explorar a relação entre as medidas não farmacológicas e as estimativas de eficiência. Os resultados indicam quais paÃses e regiões se destacaram, apresentando respostas mais eficientes/ineficientes, bem como apontam para uma relação negativo que as variáveis idade mediana, Ãndice médio de restrição e alteração média no número de visitantes em lojas e locais recreativos tiveram nas estimativas de eficiência
An Examination of Missing Person Social Media Engagement Through Data Mining and Experimentation: An Application of the Crisis and Emergency Risk Communication Model
According to the Federal Bureau of Investigation (FBI), approximately 600,000 individuals are reported missing each year in the United States (2022). When missing person cases do not meet alert (e.g., AMBER) criteria, law enforcement often utilize social media to crowdsource information to ultimately return the missing home. Therefore, guided by the crisis and emergency risk communication model (CERC; Reynolds & Seeger, 2005) and its recently clarified propositions (Miller et al., 2021), the purpose of this dissertation was to (a) identify strategies law enforcement use to crowdsource missing person information and (b) experimentally test message characteristics that facilitate prosocial sharing of missing person posts on social media. In study one, a quantitative content analysis of 600 extracted missing person X (Twitter) posts identified that all CERC model message characteristics (i.e., timeliness, accuracy, source credibility, empathy, action-orientation, respect) were present in current law enforcement crowdsourcing posts. Additionally, a linear regression analysis indicated that timeliness, empathy, and respect predict message engagement (i.e., retweets, likes, replies) and were used to inform experimental messages in study two. In study two, participants (N = 377) who were 18 years or older and use X (Twitter) were randomly assigned one pilot tested experimental missing person message (i.e., timeliness, empathy, respect, or control). Parallel multiple mediation analyses indicated that timeliness is positively related to self-efficacy and uncertainty; empathy is positively related to self-efficacy, knowledge of risks and resources, and emotional turmoil; and respect is positively related to self-efficacy and uncertainty as well as negatively related to emotional turmoil. Additionally, self-efficacy, uncertainty, and emotional turmoil are positively related to behavioral intention whereas only self-efficacy and emotional turmoil can predict actual behavior. Finally, indirect relationships exist between timeliness and behavioral intention through self-efficacy and uncertainty; empathy and behavioral intention through self-efficacy and emotional turmoil; as well as respect and behavioral intention through self-efficacy, uncertainty, and emotional turmoil. This inquiry offers theoretical implications by being one of the first to experimentally investigate the recently clarified propositions of the CERC model. Practically, this work provides law enforcement with clear recommendations on crafting missing person messages on social media
Obesityand female infertility
De gevolgen van wereldwijd in toenemende mate voorkomend overgewicht (BMI 25‒29.9) en obesitas (BMI >30) zijn zeer zorgelijk voor de vrouwelijke voortplanting. Deze gevolgen maken het nodig dat net als in andere disciplines ook gynaecologen prioriteit geven aan deze chronische ziekte in klinische behandelingsprotocollen en wetenschappelijk onderzoek. Bij vrouwen met obesitas zijn de kansen op spontane conceptie lager en is er een verhoogd risico op miskramen, in tegenstelling tot vrouwen van normaal lichaamsgewicht. Hierdoor hebben meer vrouwen met obesitas een vruchtbaarheidsbehandeling nodig, terwijl deze patiënten tegelijkertijd meer gonadotrofines voor ovariële hyperstimulatie nodig hebben en minder zwangerschappen en levend geboren kinderen verkrijgen met de ingestelde behandelingen. Deze aan obesitas gerelateerde zwangerschapscomplicaties vormen een grote zorg vanwege de toename van perinatale sterfte en zelfs van moedersterfte in gevallen van ernstige (BMI 35‒39.9 kg/m2) en morbide (BMI >40 kg/m2) obesitas. Obesitas tijdens zwangerschap leidt bij nakomelingen tot een verhoogde kans op ziektes op de lange termijn vanwege het ongunstige intra-uterien milieu tijdens de foetale ontwikkeling. De studies in dit proefschrift werden uitgevoerd om de verschillende aspecten van obesitas en vrouwelijke onvruchtbaarheid te onderzoeken. Het belangrijkste aandachtspunt was de rol en de invloed van de verdeling van lichaamsvet, in het bijzonder intra-abdominaal vet (IAF) en subcutane abdominaal vet (SAF), bij vrouwen met obesitas en onvruchtbaarheid die een leefstijlprogramma ondergingen. Gezien de mogelijke gevolgen van obesitas bij vrouwen die een vruchtbaarheidsbehandeling ondergaan, is het aannemelijk dat obesitas een negatieve invloed heeft op de kosteneffectiviteit van vruchtbaarheidsbehandeling. In Hoofdstuk 2 wordt een model ontwikkeld om de kosten van vruchtbaarheidsbehandelingen (d.w.z. ovulatie-inductie, intra-uteriene inseminatie en in-vitrofertilisatie) en van zwangerschapscomplicaties afzonderlijk te berekenen voor ovulatoire en anovulatoire vrouwen, met respectievelijk normaal gewicht, overgewicht en obesitas. De berekende kosten per levend geboren kind bij vrouwen met obesitas waren vergeleken met vrouwen met een normaal gewicht respectievelijk € 6045 en € 3016 bij anovulatoire vrouwen, en € 10.355 en € 6096 bij ovulatoire vrouwen. Toekomstige prospectieve studies zullen moeten uitwijzen of leefstijlinterventies gericht op gewichtsverlies voorafgaand aan een vruchtbaarheidsbehandeling de kosteneffectiviteit van vruchtbaarheidsbehandelingen per levend geboren kind bij vrouwen met obesitas zullen verbeteren
Modeling Induced Master Motion in Force-Reflecting Teleoperation
Providing the user with high-fidelity force feedback has persistently challenged the field of telerobotics. Interaction forces measured at the remote site and displayed to the user cause unintended master device motion. This movement is interpreted as a command for the slave robot and can drive the closed-loop system unstable. This paper builds on a recently proposed approach for achieving stable, high-gain force reflection via cancellation of the master mechanism’s induced motion. Such a strategy hinges on obtaining a good model of the master’s response to force feedback. Herein, we present a thorough modeling approach based on successive isolation of system components, demonstrated on a one-degree-of-freedom testbed. A sixth-order mechanical model, including viscous and Coulomb friction as well as a new method for modeling hysteretic stiffness, describes the testbed’s high-frequency resonant modes. This modeling method’s ability to predict induced master motion should lead to significant improvements in force-reflecting teleoperation via the cancellation approac
Haptic Displayof Realistic Tool Contact via Dynamically Compensated Control of a Dedicated Actuator
High frequency contact accelerations convey important information that the vast majority of haptic interfaces cannot render. Building on prior work, we present an approach to haptic interface design that uses a dedicated linear voice coil actuator and a dynamic system model to allow the user to feel these signals. This approach was tested through use in a bilateral teleoperation experiment where a user explored three textured surfaces under three different acceleration control architectures: none, constant gain, and dynamic compensation. The controllers that use the dedicated actuator vastly outperform traditional position-position control at conveying realistic contact accelerations. Analysis of root mean square error, linear regression, and discrete Fourier transforms of the acceleration data also indicate a slight performance benefit for dynamic compensation over constant gain
Improving Telerobotic Touch Via High-Frequency Acceleration Matching
Humans rely on information-laden high-frequency accelerations in addition to quasi-static forces when interacting with objects via a handheld tool. Telerobotic systems have traditionally struggled to portray such contact transients due to closed-loop bandwidth and stability limitations, leaving remote objects feeling soft and undefined. This work seeks to maximize the user’s feel for the environment through the approach of acceleration matching; high-frequency fingertip accelerations are combined with standard low-frequency position feedback without requiring a secondary actuator on the master device. In this method, the natural dynamics of the master are identified offline using frequency-domain techniques, estimating the relationship between commanded motor current and handle acceleration while a user holds the device. During subsequent telerobotic interactions, a high-bandwidth sensor measures accelerations at the slave’s end effector, and the real-time controller re-creates these important signals at the master handle by inverting the identified model. The details of this approach are explored herein, and its ability to render hard and rough surfaces is demonstrated on a standard master-slave system. Combining high-frequency acceleration matching with position-error-based feedback of quasi-static forces creates a hybrid signal that closely corresponds to human sensing capabilities, instilling telerobotics with a more realistic sense of remote touch
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