148 research outputs found
Planet Hunters. VIII. Characterization of 41 Long-Period Exoplanet Candidates from Kepler Archival Data
The census of exoplanets is incomplete for orbital distances larger than 1
AU. Here, we present 41 long-period planet candidates in 38 systems identified
by Planet Hunters based on Kepler archival data (Q0-Q17). Among them, 17
exhibit only one transit, 14 have two visible transits and 10 have more than
three visible transits. For planet candidates with only one visible transit, we
estimate their orbital periods based on transit duration and host star
properties. The majority of the planet candidates in this work (75%) have
orbital periods that correspond to distances of 1-3 AU from their host stars.
We conduct follow-up imaging and spectroscopic observations to validate and
characterize planet host stars. In total, we obtain adaptive optics images for
33 stars to search for possible blending sources. Six stars have stellar
companions within 4". We obtain high-resolution spectra for 6 stars to
determine their physical properties. Stellar properties for other stars are
obtained from the NASA Exoplanet Archive and the Kepler Stellar Catalog by
Huber et al. (2014). We validate 7 planet candidates that have planet
confidence over 0.997 (3-{\sigma} level). These validated planets include 3
single-transit planets (KIC-3558849b, KIC-5951458b, and KIC-8540376c), 3
planets with double transits (KIC-8540376b, KIC-9663113b, and KIC-10525077b),
and 1 planet with 4 transits (KIC-5437945b). This work provides assessment
regarding the existence of planets at wide separations and the associated false
positive rate for transiting observation (17%-33%). More than half of the
long-period planets with at least three transits in this paper exhibit transit
timing variations up to 41 hours, which suggest additional components that
dynamically interact with the transiting planet candidates. The nature of these
components can be determined by follow-up radial velocity and transit
observations.Comment: Published on ApJ, 815, 127 Notations of validated planets are changed
in accordance with naming convention of NASA Exoplanet Archiv
Dynamics of fluctuations in a fluid below the onset of Rayleigh-B\'enard convection
We present experimental data and their theoretical interpretation for the
decay rates of temperature fluctuations in a thin layer of a fluid heated from
below and confined between parallel horizontal plates. The measurements were
made with the mean temperature of the layer corresponding to the critical
isochore of sulfur hexafluoride above but near the critical point where
fluctuations are exceptionally strong. They cover a wide range of temperature
gradients below the onset of Rayleigh-B\'enard convection, and span wave
numbers on both sides of the critical value for this onset. The decay rates
were determined from experimental shadowgraph images of the fluctuations at
several camera exposure times. We present a theoretical expression for an
exposure-time-dependent structure factor which is needed for the data analysis.
As the onset of convection is approached, the data reveal the critical
slowing-down associated with the bifurcation. Theoretical predictions for the
decay rates as a function of the wave number and temperature gradient are
presented and compared with the experimental data. Quantitative agreement is
obtained if allowance is made for some uncertainty in the small spacing between
the plates, and when an empirical estimate is employed for the influence of
symmetric deviations from the Oberbeck-Boussinesq approximation which are to be
expected in a fluid with its density at the mean temperature located on the
critical isochore.Comment: 13 pages, 10 figures, 52 reference
Designing Hybrid Gifts
Hybrid gifting combines physical artefacts and experiences with digital interactivity to generate new kinds of gifts. Our review details how gifting is a complex social phenomenon and how digital gifting is less engaging than physical gifting for both givers and receivers. Employing a Research Through Design approach, we developed a portfolio of four hybrid gifting experiences: an augmented advent calendar; edible music tracks; personalised museum tours; and a narrated city walk. Our reflection addresses three concepts: hybrid wrapping where physical gifts become wrapped in digital media and vice versa; the importance of effortful interactions that are visible and pleasurable; and the need to consider social obligation, including opportunities for acknowledgement and reciprocation, dealing with embarrassment, and recognising the distinction between giving and sharing. Our concepts provide guidance to practitioners who wish to design future gifting experiences while helping HCI researchers engage with the concept of gifting in a nuanced way
The role of emotions on consumers’ satisfaction within the fitness context
Previous studies have suggested that consumption-related emotions are important to understand post-purchase
reactions. This study examines the relationship between fitness consumers’ emotions and overall satisfaction. After an
initial step of free-thought listing and content validity, followed by a pre-test, a survey was conducted among consumers
of five different fitness centers (n=786). The questionnaire included measures to assess positive and negative emotions,
as well as overall satisfaction with the fitness center. The results gathered through a structural equation model provide
evidence that negative emotion experienced by consumers impacts negatively overall satisfaction, while positive emotion
have a positive effect on overall satisfaction. These findings suggest managerial implications, such as the need to collect
consumers’ perceptions of both tangible and intangible aspects of the services, listen costumers’ opinions in a regular
basis, and provide regular training to staff members, in order to identify the triggers of positive emotions and contribute
to increased levels of overall satisfaction. Guidelines for future research within the fitness context are also suggested.Estudos precedentes sugerem
que as emoções relacionadas com o consumo são importantes para compreender as reações dos consumidores após a
compra. Este estudo analisa a relação entre as emoções dos consumidores de fitness e satisfação global. Depois de uma
etapa inicial de listagem de pensamento-livre e validade de conteúdo, seguido de um pré-teste, foi realizada uma pesquisa
entre os consumidores de cinco centros de fitness diferentes (n = 786). O questionário incluiu medidas para avaliar as
emoções positivas e negativas, bem como a satisfação global com o centro de fitness. Os resultados obtidos através de
um modelo de equações estruturais forneceram evidências de que as emoções negativas vivenciadas pelos consumidores
impactam negativamente a satisfação global, enquanto as emoções positivas têm um efeito positivo sobre a satisfação
global. Estes resultados sugerem implicações para os gestores, tais como a necessidade de recolher informação sobre a
perceção dos consumidores dos aspetos tangíveis e intangíveis dos serviços, ouvir regularmente as opiniões dos consumidores
e facultar formação regular aos colaboradores. Isto permitirá identificar os aspetos que desencadeiam emoções
positivas e contribuir para o aumento dos níveis de satisfação global. Orientações para futuras pesquisas no contexto de
fitness também são sugeridas.Sin financiación0.185 SJR (2015) Q3, 1090/1779 Medicine (miscellaneous); Q4, 177/229 Health (social science), 112/128 Sports scienceUE
Reframing gender and feminist knowledge construction in marketing and consumer research: missing feminisms and the case of men and masculinities
Gender has been theorised and studied in many ways and across different disciplines. Although a number of these theorisations have been recognised and adopted in marketing and consumer research, the significance of feminism in knowledge construction has largely remained what we would call ‘unfinished’. Based on a critical reframing of gender research in marketing and consumer research, in dialogue with feminist theory, this article offers theoretical and practical suggestions for how to reinvigorate these research efforts. The analysis highlights dominant theorisations of gender, relating to gender as variable, difference and role; as fundamental difference and structuring; and as cultural and identity constructions. This reframing emphasises various neglected or ‘missing feminisms’, including queer theory; critical race, intersectional and transnational feminisms; material-discursive feminism; and critical studies on men and masculinities. A more detailed discussion of the latter, as a relatively new, growing and politically contentious area, is further developed to highlight more specifically which feminist and gender theories are mainly in use in marketing and consumer research and which are little or not used. In the light of this, it is argued that marketing and related disciplines have thus far largely neglected several key contemporary gender and feminist theorisations, particularly those that centre on gender power relations. The potential impact of these theoretical frames on transdisciplinary studies in marketing and consumer research and research agenda(s) is discussed
Modeling Brain Resonance Phenomena Using a Neural Mass Model
Stimulation with rhythmic light flicker (photic driving) plays an important role in the diagnosis of schizophrenia, mood disorder, migraine, and epilepsy. In particular, the adjustment of spontaneous brain rhythms to the stimulus frequency (entrainment) is used to assess the functional flexibility of the brain. We aim to gain deeper understanding of the mechanisms underlying this technique and to predict the effects of stimulus frequency and intensity. For this purpose, a modified Jansen and Rit neural mass model (NMM) of a cortical circuit is used. This mean field model has been designed to strike a balance between mathematical simplicity and biological plausibility. We reproduced the entrainment phenomenon observed in EEG during a photic driving experiment. More generally, we demonstrate that such a single area model can already yield very complex dynamics, including chaos, for biologically plausible parameter ranges. We chart the entire parameter space by means of characteristic Lyapunov spectra and Kaplan-Yorke dimension as well as time series and power spectra. Rhythmic and chaotic brain states were found virtually next to each other, such that small parameter changes can give rise to switching from one to another. Strikingly, this characteristic pattern of unpredictability generated by the model was matched to the experimental data with reasonable accuracy. These findings confirm that the NMM is a useful model of brain dynamics during photic driving. In this context, it can be used to study the mechanisms of, for example, perception and epileptic seizure generation. In particular, it enabled us to make predictions regarding the stimulus amplitude in further experiments for improving the entrainment effect
Customer emotions in service failure and recovery encounters
Emotions play a significant role in the workplace, and considerable attention has been given to the study of employee emotions. Customers also play a central function in organizations, but much less is known about customer emotions. This chapter reviews the growing literature on customer emotions in employee–customer interfaces with a focus on service failure and recovery encounters, where emotions are heightened. It highlights emerging themes and key findings, addresses the measurement, modeling, and management of customer emotions, and identifies future research streams. Attention is given to emotional contagion, relationships between affective and cognitive processes, customer anger, customer rage, and individual differences
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