1,274 research outputs found
Communicating Product Sustainability: Consumer Responses to Sustainability Labeling in a Retail Laboratory Environment
In effort to enhance sustainable development, manufacturers and retailers have collaborated to develop a standardized sustainability index based on supply chain life cycle information. However, it is unclear whether this index will help consumers make more sustainable purchases. Research conducted in a retail laboratory addresses consumer attitudes, purchase intentions, and product choices with and without a credible standardized sustainability index, and with or without provision of background sustainability information. Results from a pilot study and two mixed design experiments indicate that, on average, consumers focus more on brand equity than on sustainability levels when they make brand choices. While the disclosure of credible information for brands within a product category affects brand-level sustainability perceptions, there are limited effects on brand purchase intentions and choices. Results also reveal a consumer misconception that nationally recognized brands are more sustainable. Implications of results are offered for producers, retailers, and public policy makers
Sum-frequency generation from etchless lithium niobate empowered by dual quasi-bound states in the continuum
The miniaturization of nonlinear light sources is central to the integrated
photonic platform, driving a quest for high-efficiency frequency generation and
mixing at the nanoscale. In this quest, the high-quality () resonant
dielectric nanostructures hold great promise, as they enhance nonlinear effects
through the resonantly local electromagnetic fields overlapping the chosen
nonlinear materials. Here, we propose a method for the enhanced sum-frequency
generation (SFG) from etcheless lithium niobate (LiNbO) by utilizing the
dual quasi-bound states in the continuum (quasi-BICs) in a one-dimensional
resonant grating waveguide structure. Two high- guided mode resonances
corresponding to the dual quasi-BICs are respectively excited by two
near-infrared input beams, generating a strong visible SFG signal with a
remarkably high conversion efficiency of (which is five
orders of magnitude higher than that of LiNbO films of the same
thickness) and a small full-width at half-maximum less than 0.2 nm. The SFG
efficiency can be tuned via adjusting the grating geometry parameter or
choosing the input beam polarization combination. Furthermore, the generated
SFG signal can be maintained at a fixed wavelength without the appreciable loss
of efficiency by selectively exciting the angular-dependent quasi-BICs, even if
the wavelengths of input beams are tuned within a broad spectral range. Our
results provide a simple but robust paradigm of high-efficiency frequency
conversion on an easy-fabricated platform, which may find applications in
nonlinear light sources and quantum photonics
EDIS: Entity-Driven Image Search over Multimodal Web Content
Making image retrieval methods practical for real-world search applications
requires significant progress in dataset scales, entity comprehension, and
multimodal information fusion. In this work, we introduce
\textbf{E}ntity-\textbf{D}riven \textbf{I}mage \textbf{S}earch (EDIS), a
challenging dataset for cross-modal image search in the news domain. EDIS
consists of 1 million web images from actual search engine results and curated
datasets, with each image paired with a textual description. Unlike datasets
that assume a small set of single-modality candidates, EDIS reflects real-world
web image search scenarios by including a million multimodal image-text pairs
as candidates. EDIS encourages the development of retrieval models that
simultaneously address cross-modal information fusion and matching. To achieve
accurate ranking results, a model must: 1) understand named entities and events
from text queries, 2) ground entities onto images or text descriptions, and 3)
effectively fuse textual and visual representations. Our experimental results
show that EDIS challenges state-of-the-art methods with dense entities and a
large-scale candidate set. The ablation study also proves that fusing textual
features with visual features is critical in improving retrieval results
Efficient photon-pair generation empowered by dual quasi-bound states in the continuum
Here we demonstrate the efficient photon-pair generation via spontaneous
parametric down conversion from a semiconductor metasurface supporting dual
quasi-bound states in the continuum (quasi-BICs). In a simple metasurface
design composed of AlGaAs ellipse nano-cyclinders, the two high- quasi-BIC
resonances that coincide with the generated signal and idler frequencies
significantly boost the local electric field. This leads to a substantial
enhancement in the reverse classical nonlinear process of sum frequency
generation and subsequently the remarkable high generation rate of photon pairs
under the quantum-classical correspondence principle. Within a narrowband
wavelength regime around the quasi-BIC resonances, the rate of pair production
is enhanced up to Hz, two orders of magnitude larger than that in
the Mie resonant AlGaAs nanoantennas. Moreover, the photon pair emission is
mainly concentrated in the normal direction with respect to the metasurface,
and shows tunable rate with the factor by engineering the rotation angle of
nano-cylinders. The presented work enables nanoscale sources of high-quality
entangled photons which will find applications in advanced quantum imaging and
communications
Subject-centered multi-view feature fusion for neuroimaging retrieval and classification
Multi-View neuroimaging retrieval and classification play an important role in computer-aided-diagnosis of brain disorders, as multi-view features could provide more insights of the disease pathology and potentially lead to more accurate diagnosis than single-view features. The large inter-feature and inter-subject variations make the multi-view neuroimaging analysis a challenging task. Many multi-view or multi-modal feature fusion methods have been proposed to reduce the impact of inter-feature variations in neuroimaging data. However, there is not much in-depth work focusing on the inter-subject variations. In this study, we propose a subject-centered multi-view feature fusion method for neuroimaging retrieval and classification based on the propagation graph fusion (PGF) algorithm. Two main advantages of the proposed method are: 1) it evaluates the query online and adaptively reshapes the connections between subjects according to the query; 2) it measures the affinity of the query to the subjects using the subject-centered affinity matrices, which can be easily combined and efficiently solved. Evaluated using a public accessible neuroimaging database, our algorithm outperforms the state-of-the-art methods in retrieval and achieves comparable performance in classification
Rivulet: 3D Neuron Morphology Tracing with Iterative Back-Tracking
The digital reconstruction of single neurons from 3D confocal microscopic images is an important tool for understanding the neuron morphology and function. However the accurate automatic neuron reconstruction remains a challenging task due to the varying image quality and the complexity in the neuronal arborisation. Targeting the common challenges of neuron tracing, we propose a novel automatic 3D neuron reconstruction algorithm, named Rivulet, which is based on the multi-stencils fast-marching and iterative backtracking. The proposed Rivulet algorithm is capable of tracing discontinuous areas without being interrupted by densely distributed noises. By evaluating the proposed pipeline with the data provided by the Diadem challenge and the recent BigNeuron project, Rivulet is shown to be robust to challenging microscopic imagestacks. We discussed the algorithm design in technical details regarding the relationships between the proposed algorithm and the other state-of-the-art neuron tracing algorithms
Sulphur isotopes toward Sagittarius B2 extended envelope in the Galactic Center
The isotopic ratios are good tools for probing the stellar nucleosynthesis
and chemical evolution. We performed high-sensitivity mapping observations of
the J=7-6 rotational transitions of OCS, OC34S, O13CS, and OC33S toward the
Galactic Center giant molecular cloud, Sagittarius B2 (Sgr B2) with IRAM 30m
telescope. Positions with optically thin and uncontaminated lines are chosen to
determine the sulfur isotope ratios. A 32S/34S ratio of 17.1\pm0.9 was derived
with OCS and OC34S lines, while 34S/33S ratio of 6.8\pm1.9 was derived directly
from integrated intensity ratio of OC34S and OC33S. With independent and
accurate measurements of 32S/34S ratio, our results confirm the termination of
the decreasing trend of 32S/34S ratios toward the Galactic Center, suggesting a
drop in the production of massive stars at the Galactic centre.Comment: 20 pages, 7 figures, accepted by PAS
Reconstruction of 3D neuron morphology using Rivulet back-tracking
The 3D reconstruction of neuronal morphology is a powerful technique for investigating nervous systems. Due to the noises in optical microscopic images, the automated reconstruction of neuronal morphology has been a challenging problem. We propose a novel automatic neuron reconstruction algorithm, Rivulet, to target the challenges raised by the poor quality of the optical microscopic images. After the neuron images being de-noised with an anisotropic filter, the Rivulet algorithm combines multi-stencils fast-marching and iterative back-tracking from the geodesic farthest point on the segmented foreground. The neuron segments are dumped or merged according to a set of criteria at the end of each iteration. The proposed Rivulet tracing algorithm is evaluated with data provided from the BigNeuron Project. The experimental results demonstrate that Rivulet outperforms the compared state-of-the-art tracing methods when the images are of poor quality
The Frontier of Tungsten Oxide Nanostructures in Electronic Applications
Electrochromic (EC) glazing has garnered significant attention recently as a crucial solution for enhancing energy efficiency in future construction and automotive sectors. EC glazing could significantly reduce the energy usage of buildings compared to traditional blinds and glazing. Despite their commercial availability, several challenges remain, including issues with switching time, leakage of electrolytes, production costs, etc. Consequently, these areas demand more attention and further studies. Among inorganic-based EC materials, tungsten oxide nanostructures are essential due to its outstanding advantages such as low voltage demand, high coloration coefficient, large optical modulation range, and stability. This review will summarize the principal design and mechanism of EC device fabrication. It will highlight the current gaps in understanding the mechanism of EC theory, discuss the progress in material development for EC glazing, including various solutions for improving EC materials, and finally, introduce the latest advancements in photo-EC devices that integrate photovoltaic and EC technologies
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