94 research outputs found
ReSLLM: Large Language Models are Strong Resource Selectors for Federated Search
Federated search, which involves integrating results from multiple
independent search engines, will become increasingly pivotal in the context of
Retrieval-Augmented Generation pipelines empowering LLM-based applications such
as chatbots. These systems often distribute queries among various search
engines, ranging from specialized (e.g., PubMed) to general (e.g., Google),
based on the nature of user utterances. A critical aspect of federated search
is resource selection - the selection of appropriate resources prior to issuing
the query to ensure high-quality and rapid responses, and contain costs
associated with calling the external search engines. However, current SOTA
resource selection methodologies primarily rely on feature-based learning
approaches. These methods often involve the labour intensive and expensive
creation of training labels for each resource. In contrast, LLMs have exhibited
strong effectiveness as zero-shot methods across NLP and IR tasks. We
hypothesise that in the context of federated search LLMs can assess the
relevance of resources without the need for extensive predefined labels or
features. In this paper, we propose ReSLLM. Our ReSLLM method exploits LLMs to
drive the selection of resources in federated search in a zero-shot setting. In
addition, we devise an unsupervised fine tuning protocol, the Synthetic Label
Augmentation Tuning (SLAT), where the relevance of previously logged queries
and snippets from resources is predicted using an off-the-shelf LLM and then in
turn used to fine-tune ReSLLM with respect to resource selection. Our empirical
evaluation and analysis details the factors influencing the effectiveness of
LLMs in this context. The results showcase the merits of ReSLLM for resource
selection: not only competitive effectiveness in the zero-shot setting, but
also obtaining large when fine-tuned using SLAT-protocol
Selecting which Dense Retriever to use for Zero-Shot Search
We propose the new problem of choosing which dense retrieval model to use
when searching on a new collection for which no labels are available, i.e. in a
zero-shot setting. Many dense retrieval models are readily available. Each
model however is characterized by very differing search effectiveness -- not
just on the test portion of the datasets in which the dense representations
have been learned but, importantly, also across different datasets for which
data was not used to learn the dense representations. This is because dense
retrievers typically require training on a large amount of labeled data to
achieve satisfactory search effectiveness in a specific dataset or domain.
Moreover, effectiveness gains obtained by dense retrievers on datasets for
which they are able to observe labels during training, do not necessarily
generalise to datasets that have not been observed during training. This is
however a hard problem: through empirical experimentation we show that methods
inspired by recent work in unsupervised performance evaluation with the
presence of domain shift in the area of computer vision and machine learning
are not effective for choosing highly performing dense retrievers in our setup.
The availability of reliable methods for the selection of dense retrieval
models in zero-shot settings that do not require the collection of labels for
evaluation would allow to streamline the widespread adoption of dense
retrieval. This is therefore an important new problem we believe the
information retrieval community should consider. Implementation of methods,
along with raw result files and analysis scripts are made publicly available at
https://www.github.com/anonymized
Weight of Evidence Method and Its Applications and Development
AbstractThe development and applications about the weight of evidence technology in recent years are reviewed. This paper introduced the improved weight of evidence in remote sensing image processing and in different fields of application. Summary its constraints and existent problems. Look forward to the weight of evidence for the practical application
Zero-shot Generative Large Language Models for Systematic Review Screening Automation
Systematic reviews are crucial for evidence-based medicine as they
comprehensively analyse published research findings on specific questions.
Conducting such reviews is often resource- and time-intensive, especially in
the screening phase, where abstracts of publications are assessed for inclusion
in a review. This study investigates the effectiveness of using zero-shot large
language models~(LLMs) for automatic screening. We evaluate the effectiveness
of eight different LLMs and investigate a calibration technique that uses a
predefined recall threshold to determine whether a publication should be
included in a systematic review. Our comprehensive evaluation using five
standard test collections shows that instruction fine-tuning plays an important
role in screening, that calibration renders LLMs practical for achieving a
targeted recall, and that combining both with an ensemble of zero-shot models
saves significant screening time compared to state-of-the-art approaches.Comment: Accepted to ECIR2024 full paper (findings
Phase diagram of superconducting vortex ratchet motion in a superlattice with noncentrosymmetry
Ratchet motion of superconducting vortices, which is a directional flow of
vortices in superconductors, is highly useful for exploring quantum phenomena
and developing superconducting devices, such as superconducting diode and
microwave antenna. However, because of the challenges in the quantitative
characterization of the dynamic motion of vortices, a phase diagram of the
vortex ratchet motion is still missing, especially in the superconductors with
low dimensional structures. Here we establish a quantitative phase diagram of
the vortex ratchet motion in a highly anisotropic superlattice superconductor,
(SnS)1.17NbS2, using nonreciprocal magnetotransport. The (SnS)1.17NbS2, which
possesses a layered atomic structure and noncentrosymmetry, exhibits
nonreciprocal magnetotransport in a magnetic field perpendicular and parallel
to the plane, which is considered a manifest of ratchet motion of
superconducting vortices. We demonstrated that the ratchet motion is responsive
to current excitation, magnetic field and thermal perturbation. Furthermore, we
extrapolated a giant nonreciprocal coefficient ({\gamma}), which quantitatively
describes the magnitude of the vortex ratchet motion, and eventually
established phase diagrams of the ratchet motion of the vortices with a
quantitative description. Last, we propose that the ratchet motion originates
from the coexistence of pancake vortices (PVs) and Josephson vortices (JVs).
The phase diagrams are desirable for controlling the vortex motion in
superlattice superconductors and developing next-generation energy-efficient
superconducting devices
Submarine groundwater discharge in Dongshan Bay, China: A master regulator of nutrients in spring and potential national significance of small bays
Despite over 90% of China’s coastal bays have an area less than 500 km2, the geochemical effects of SGD on those ecosystems are ambiguous. Based on mapping and time-series observations of Ra isotopes and nutrients, a case study of small bays (<500 km2), we revealed that submarine groundwater discharge (SGD) predominately regulated the distribution of nutrients and fueled algal growth in Dongshan Bay, China. On the bay-wide scale, the SGD rate was estimated to be 0.048 ± 0.022 m day−1 and contributed over 95% of the nutrients. At the time-series site where the bay-wide highest Ra activities in the bottom water marked an SGD hotspot with an average rate an order of magnitude greater, the maximum chlorophyll concentration co-occurred, suggesting that SGD may support the algal bloom. The ever-most significant positive correlations between 228Ra and nutrients throughout the water column (P< 0.01, R2 > 0.90 except for soluble reactive phosphorus in the surface) suggested the predominance of SGD in controlling nutrient distribution in the bay. Extrapolated to a national scale, the SGD-carried dissolved inorganic nitrogen flux in small bays was twice as much as those in large bays (>2,000 km2). Thus, the SGD-carried nutrients in small bays merit immediate attention in environmental monitoring and management
Giant third-order nonlinear Hall effect in misfit layer compound (SnS)(NbS)
Nonlinear Hall effect (NLHE) holds immense significance in recognizing the
band geometry and its potential applications in current rectification. Recent
discoveries have expanded the study from second-order to third-order nonlinear
Hall effect (THE), which is governed by an intrinsic band geometric quantity
called the Berry Connection Polarizability (BCP) tensor. Here we demonstrate a
giant THE in a misfit layer compound, (SnS)(NbS). While the THE
is prohibited in individual NbS and SnS due to the constraints imposed by
the crystal symmetry and their band structures, a remarkable THE emerges when a
superlattice is formed by introducing a monolayer of SnS. The angular-dependent
THE and its scaling relationship indicate that the phenomenon could be
correlated to the band geometry modulation, concurrently with the symmetry
breaking. The resulting strength of THE is orders of magnitude higher compared
to recent studies. Our work illuminates the modulation of structural and
electronic geometries for novel quantum phenomena through interface
engineering
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