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Application of the Theory of Planned Behavior to Understand Traveler Behavior Affected by COVID-19: A Qualitative Study
With the pandemic still intact, understanding how COVID-19 affects traveler behaviors may be critical to the tourism industry. While much research has been conducted related to COVID-19’s impact on travel, little research has examined the underlying determinants of changes in behavior, and whether these changes will continue over time. This qualitative study was grounded in the Theory of Planned Behavior (TPB), Plog\u27s travel model, and the concept of constraint negotiation, to better understand the impact of COVID-19 on travel behavior through in-depth interviews. Preliminary results found that travelers\u27 attitudes, social norms, and perceived behavioral control were influenced by COVID-19, and the degree of influence may be related to their tendency toward being allocentric or psychocentric. Travelers\u27 ability to negotiate constraints was also found to be related to their attitudes, which extends the theory of TPB. This study also provides suggestions for tourism companies’ marketing strategies post-pandemic
Direct Growth of Copper Oxide Films on Ti Substrate for Nonenzymatic Glucose Sensors
Copper oxide (CuO) films directly grown on Ti substrate have been successfully prepared via a hydrothermal method and used to construct an amperometric nonenzymatic glucose sensor. XRD and SEM were used to characterize the samples. The electrochemical performances of the electrode for detection of glucose were investigated by cyclic voltammetry and chronoamperometry. The CuO films based glucose sensors exhibit enhanced electrocatalytic properties which show very high sensitivity (726.9 μA mM−1 cm−2), low detection limit (2 μM), and fast response (2 s). In addition, reproducibility and long-term stability have been observed. Low cost, convenience, and biocompatibility make the CuO films directly grown on Ti substrate electrodes a promising platform for amperometric nonenzymatic glucose sensor
Meshless deformable models for LV motion analysis
We propose a novel meshless deformable model for in vivo cardiac left ventricle (LV) 3D motion estimation. As a relatively new technology, tagged MRI (tMRI) provides a direct and noninvasive way to reveal local deformation of the myocardium, which creates a large amount of heart motion data which requiring quantitative analysis. In our study, we sample the heart motion sparsely at intersections of three sets of orthogonal tagging planes and then use a new meshless deformable model to recover the dense 3D motion of the myocardium temporally during the cardiac cycle. We compute external forces at tag intersections based on tracked local motion and redistribute the force to meshless particles throughout the myocardium. Internal constraint forces at particles are derived from local strain energy using a Moving Least Squares (MLS) method. The dense 3D motion field is then computed and updated using the Lagrange equation. The new model avoids the singularity problem of mesh-based models and is capable of tracking large deformation with high efficiency and accuracy. In particular, the model performs well even when the control points (tag intersections) are relatively sparse. We tested the performance of the meshless model on a numerical phantom, as well as in vivo heart data of healthy subjects and patients. The experimental results show that the meshless deformable model can fully recover the myocardium motion in 3D. 1
Determining anomalies in a semilinear elliptic equation by a minimal number of measurements
We are concerned with the inverse boundary problem of determining anomalies
associated with a semilinear elliptic equation of the form , where is a general nonlinear term that belongs to a
H\"older class. It is assumed that the inhomogeneity of is
contained in a bounded domain in the sense that outside , with . We establish novel unique
identifiability results in several general scenarios of practical interest.
These include determining the support of the inclusion (i.e. ) independent
of its content (i.e. in ) by a single boundary
measurement; and determining both and by boundary
measurements, where signifies the number of unknown
coefficients in . The mathematical argument is based on
microlocally characterising the singularities in the solution induced by
the geometric singularities of , and does not rely on any linearisation
technique
Multi-sensor Suboptimal Fusion Student's Filter
A multi-sensor fusion Student's filter is proposed for time-series
recursive estimation in the presence of heavy-tailed process and measurement
noises. Driven from an information-theoretic optimization, the approach extends
the single sensor Student's Kalman filter based on the suboptimal
arithmetic average (AA) fusion approach. To ensure computationally efficient,
closed-form density recursion, reasonable approximation has been used in
both local-sensor filtering and inter-sensor fusion calculation. The overall
framework accommodates any Gaussian-oriented fusion approach such as the
covariance intersection (CI). Simulation demonstrates the effectiveness of the
proposed multi-sensor AA fusion-based filter in dealing with outliers as
compared with the classic Gaussian estimator, and the advantage of the AA
fusion in comparison with the CI approach and the augmented measurement fusion.Comment: 8 pages, 8 figure
Empirical Pricing of Chinese Defaultable Corporate Bonds Based on the Incomplete Information Model
The default of Suntech Power made the year 2013 in China “the first year of default” of bond markets. People are also clearly aware of the default risk of corporate bonds and find that fair pricing for defaultable corporate bonds is very important. In this paper we first give the pricing model based on incomplete information, then empirically price the Chinese corporate bond “11 super JGBS” from Merton’s model, reduced-form model, and incomplete information model, respectively, and then compare the obtained prices with the real prices. Results show that all the three models can reflect the trend of bond prices, but the incomplete information model fits the real prices best. In addition, the default probability obtained from the incomplete information model can discriminate the credit quality of listed companies
Multi-level Gated Bayesian Recurrent Neural Network for State Estimation
The optimality of Bayesian filtering relies on the completeness of prior
models, while deep learning holds a distinct advantage in learning models from
offline data. Nevertheless, the current fusion of these two methodologies
remains largely ad hoc, lacking a theoretical foundation. This paper presents a
novel solution, namely a multi-level gated Bayesian recurrent neural network
specifically designed to state estimation under model mismatches. Firstly, we
transform the non-Markov state-space model into an equivalent first-order
Markov model with memory. It is a generalized transformation that overcomes the
limitations of the first-order Markov property and enables recursive filtering.
Secondly, by deriving a data-assisted joint state-memory-mismatch Bayesian
filtering, we design a Bayesian multi-level gated framework that includes a
memory update gate for capturing the temporal regularities in state evolution,
a state prediction gate with the evolution mismatch compensation, and a state
update gate with the observation mismatch compensation. The Gaussian
approximation implementation of the filtering process within the gated
framework is derived, taking into account the computational efficiency.
Finally, the corresponding internal neural network structures and end-to-end
training methods are designed. The Bayesian filtering theory enhances the
interpretability of the proposed gated network, enabling the effective
integration of offline data and prior models within functionally explicit gated
units. In comprehensive experiments, including simulations and real-world
datasets, the proposed gated network demonstrates superior estimation
performance compared to benchmark filters and state-of-the-art deep learning
filtering methods
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