69 research outputs found
Segmentation-by-Detection: A Cascade Network for Volumetric Medical Image Segmentation
We propose an attention mechanism for 3D medical image segmentation. The
method, named segmentation-by-detection, is a cascade of a detection module
followed by a segmentation module. The detection module enables a region of
interest to come to attention and produces a set of object region candidates
which are further used as an attention model. Rather than dealing with the
entire volume, the segmentation module distills the information from the
potential region. This scheme is an efficient solution for volumetric data as
it reduces the influence of the surrounding noise which is especially important
for medical data with low signal-to-noise ratio. Experimental results on 3D
ultrasound data of the femoral head shows superiority of the proposed method
when compared with a standard fully convolutional network like the U-Net
End-to-end detection-segmentation network with ROI convolution
We propose an end-to-end neural network that improves the segmentation
accuracy of fully convolutional networks by incorporating a localization unit.
This network performs object localization first, which is then used as a cue to
guide the training of the segmentation network. We test the proposed method on
a segmentation task of small objects on a clinical dataset of ultrasound
images. We show that by jointly learning for detection and segmentation, the
proposed network is able to improve the segmentation accuracy compared to only
learning for segmentation. Code is publicly available at
https://github.com/vincentzhang/roi-fcn.Comment: ISBI 201
Near 6 GHz Sezawa Mode Surface Acoustic Wave Resonators using AlScN on SiC
Surface Acoustic Wave (SAW) devices featuring Aluminum Scandium Nitride
(AlScN) on a 4H-Silicon Carbide (SiC) substrate, offer a unique blend of high
sound velocity, low thermal resistance, substantial piezoelectric response,
simplified fabrication, as well as suitability for high-temperature and harsh
environment operation. This study presents high-frequency SAW resonators
employing AlScN thin films on SiC substrates, utilizing the second SAW mode
(referred to as the Sezawa mode). The resonators achieve remarkable
performance, boasting a K2 value of 5.5% and a maximum Q-factor (Qmax) of 1048
at 4.7 GHz, outperforming previous benchmarks. Additionally, a SAW resonator
with a 960 nm wavelength attains 5.9 GHz frequency with record K2 (4.0%) and
Qmax (887). Our study underscores the potential of the AlScN on SiC platform
for advanced radio-frequency applications.Comment: 19 pages, 5 figures in main text and 3 figures in supplementar
NQE: N-ary Query Embedding for Complex Query Answering over Hyper-relational Knowledge Graphs
Complex query answering (CQA) is an essential task for multi-hop and logical
reasoning on knowledge graphs (KGs). Currently, most approaches are limited to
queries among binary relational facts and pay less attention to n-ary facts
(n>=2) containing more than two entities, which are more prevalent in the real
world. Moreover, previous CQA methods can only make predictions for a few given
types of queries and cannot be flexibly extended to more complex logical
queries, which significantly limits their applications. To overcome these
challenges, in this work, we propose a novel N-ary Query Embedding (NQE) model
for CQA over hyper-relational knowledge graphs (HKGs), which include massive
n-ary facts. The NQE utilizes a dual-heterogeneous Transformer encoder and
fuzzy logic theory to satisfy all n-ary FOL queries, including existential
quantifiers, conjunction, disjunction, and negation. We also propose a parallel
processing algorithm that can train or predict arbitrary n-ary FOL queries in a
single batch, regardless of the kind of each query, with good flexibility and
extensibility. In addition, we generate a new CQA dataset WD50K-NFOL, including
diverse n-ary FOL queries over WD50K. Experimental results on WD50K-NFOL and
other standard CQA datasets show that NQE is the state-of-the-art CQA method
over HKGs with good generalization capability. Our code and dataset are
publicly available.Comment: Accepted by the 37th AAAI Conference on Artificial Intelligence
(AAAI-2023
ChatKBQA: A Generate-then-Retrieve Framework for Knowledge Base Question Answering with Fine-tuned Large Language Models
Knowledge Base Question Answering (KBQA) aims to derive answers to natural
language questions over large-scale knowledge bases (KBs), which are generally
divided into two research components: knowledge retrieval and semantic parsing.
However, three core challenges remain, including inefficient knowledge
retrieval, retrieval errors adversely affecting semantic parsing, and the
complexity of previous KBQA methods. In the era of large language models
(LLMs), we introduce ChatKBQA, a novel generate-then-retrieve KBQA framework
built on fine-tuning open-source LLMs such as Llama-2, ChatGLM2 and Baichuan2.
ChatKBQA proposes generating the logical form with fine-tuned LLMs first, then
retrieving and replacing entities and relations through an unsupervised
retrieval method, which improves both generation and retrieval more
straightforwardly. Experimental results reveal that ChatKBQA achieves new
state-of-the-art performance on standard KBQA datasets, WebQSP, and
ComplexWebQuestions (CWQ). This work also provides a new paradigm for combining
LLMs with knowledge graphs (KGs) for interpretable and knowledge-required
question answering. Our code is publicly available.Comment: Preprin
Text2NKG: Fine-Grained N-ary Relation Extraction for N-ary relational Knowledge Graph Construction
Beyond traditional binary relational facts, n-ary relational knowledge graphs
(NKGs) are comprised of n-ary relational facts containing more than two
entities, which are closer to real-world facts with broader applications.
However, the construction of NKGs still significantly relies on manual labor,
and n-ary relation extraction still remains at a course-grained level, which is
always in a single schema and fixed arity of entities. To address these
restrictions, we propose Text2NKG, a novel fine-grained n-ary relation
extraction framework for n-ary relational knowledge graph construction. We
introduce a span-tuple classification approach with hetero-ordered merging to
accomplish fine-grained n-ary relation extraction in different arity.
Furthermore, Text2NKG supports four typical NKG schemas: hyper-relational
schema, event-based schema, role-based schema, and hypergraph-based schema,
with high flexibility and practicality. Experimental results demonstrate that
Text2NKG outperforms the previous state-of-the-art model by nearly 20\% points
in the scores on the fine-grained n-ary relation extraction benchmark in
the hyper-relational schema. Our code and datasets are publicly available.Comment: Preprin
Two-stage robust planning method for distribution network energy storage based on load forecasting
A two-stage robust planning method for energy storage in distribution networks based on load prediction is proposed to address the uncertainty of active load in energy storage planning. First, considering the uncertainty of active load, a short-term load forecasting model combining the mutual information method and BiLSTM is established based on k-means++ clustering. Second, based on the results of load forecasting, a comprehensive norm-constrained uncertainty set is constructed, and a two-stage robust model for distribution network energy storage planning is established. The first stage aims to minimize the annual investment cost of the energy storage system, while the second stage aims to minimize the daily operating cost of the distribution network. At the same time, a second-order cone relaxation transformation model with non-convex constraints is introduced to ultimately achieve the optimal economy of the distribution network in energy storage planning. Finally, the effectiveness of the proposed method and model is validated on the IEEE 33-node distribution network model using the MATLAB platform
Non-linear associations of atherogenic index of plasma with prediabetes and type 2 diabetes mellitus among Chinese adults aged 45 years and above: a cross-sectional study from CHARLS
BackgroundDyslipidemia is strongly associated with the development of prediabetes and type 2 diabetes mellitus (T2DM). The atherogenic index of plasma (AIP), as a comprehensive index for assessing lipid metabolism, has received extensive attention from researchers in recent years. However, there are relatively few studies exploring the relationships between AIP and the risk of prediabetes and T2DM in the Chinese population. This study focuses on exploring the relationships of AIP with the risk of prediabetes and T2DM in the Chinese population.MethodsWe conducted an analysis of the public data from the China Health and Retirement Longitudinal Study (CHARLS), involving a total of 12,060 participants aged 45 years and above in China. The study explored the relationships of AIP with prediabetes and T2DM risk through multivariate logistic regression, subgroup analysis, smooth curve fitting, and threshold effect analysis.ResultsAfter adjusting for potential confounding factors, we observed positive associations between AIP and the risk of prediabetes [odds ratio (OR) = 1.75, 95% confidence interval (CI): 1.49–2.06] and T2DM (OR = 2.91, 95% CI: 2.38–3.57). Participants with higher AIP levels demonstrated a significantly elevated risk of prediabetes (OR = 1.52, 95% CI: 1.33–1.74) and T2DM (OR = 2.28, 95% CI: 1.92–2.71) compared to those with lower AIP levels. AIP showed consistent correlations with prediabetes and T2DM risk in different subgroups. The results showed the non-linear relationships between AIP and risk of prediabetes and T2DM, with inflection points at 0.29 and −0.04, respectively. When AIP > 0.29, there was a positive association between AIP and the risk of prediabetes (OR = 2.24, 95% CI: 1.67–3.00, p < 0.0001). Similarly, when AIP > −0.04, AIP was positively associated with the risk of T2DM (OR = 3.33, 95% CI: 2.67–4.16, p < 0.0001).ConclusionsThis study demonstrated non-linear positive associations of AIP with the risk of prediabetes and T2DM among participants ≥ 45 years of age in China
Association between complete blood count-derived inflammatory markers and the risk of frailty and mortality in middle-aged and older adults
ObjectiveThis study aimed to evaluate the association between six complete blood count (CBC)-derived inflammatory markers [neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammatory index (SII), systemic inflammatory response index (SIRI), and pan-immune inflammation value (PIV)] and the risk of frailty and mortality.MethodsData were obtained from the National Health and Nutrition Examination Survey (NHANES) 1999–2018. Mortality was identified using the National Death Index until December 31, 2019. Multiple logistic regression analysis was conducted to evaluate the association between six CBC-derived inflammatory markers and frailty. The Cox regression model assessed the association between six CBC-derived inflammatory markers and mortality in frail populations. Restricted cubic spline (RCS) was used to visualize the association of the six CBC-derived inflammatory markers with mortality risk. The predictive value of CBC-derived inflammatory markers for mortality was further assessed using a random survival forest (RSF) approach.ResultsThis study analyzed data from a total of 16,705 middle-aged and older participants. Among them, 6,503 participants were frail, with a mortality rate of 41.47%. Multiple logistic regression analysis showed that NLR, MLR, PLR, SII, SIRI, and PIV were positively associated with frailty risk. The Cox regression model revealed that participants in the highest quartile had a significantly increased risk of death compared to those in the lowest quartile: NLR (HR = 1.73, 95% CI:1.54, 1.94), MLR (HR = 1.71, 95% CI:1.51, 1.93), PLR (HR = 1.28, 95%CI: 1.15, 1.43), SII (HR = 1.50, 95%CI:1.34, 1.68), SIRI (HR = 1.88, CI 95%:1.67, 2.12), PIV (HR = 1.55, 95%CI:1.38, 1.73). Random survival forest (RSF) analyses demonstrated that MLR had the highest predictive value for mortality risk middle-aged and older adult frail participants.ConclusionThe results suggest that CBC-derived inflammatory markers are associated with a higher risk of frailty as well as mortality in the middle and old-aged population of the United States
Exploring the Potential of Integrated Optical Sensing and Communication (IOSAC) Systems with Si Waveguides for Future Networks
Advanced silicon photonic technologies enable integrated optical sensing and
communication (IOSAC) in real time for the emerging application requirements of
simultaneous sensing and communication for next-generation networks. Here, we
propose and demonstrate the IOSAC system on the silicon nitride (SiN) photonics
platform. The IOSAC devices based on microring resonators are capable of
monitoring the variation of analytes, transmitting the information to the
terminal along with the modulated optical signal in real-time, and replacing
bulk optics in high-precision and high-speed applications. By directly
integrating SiN ring resonators with optical communication networks,
simultaneous sensing and optical communication are demonstrated by an optical
signal transmission experimental system using especially filtering amplified
spontaneous emission spectra. The refractive index (RI) sensing ring with a
sensitivity of 172 nm/RIU, a figure of merit (FOM) of 1220, and a detection
limit (DL) of 8.2*10-6 RIU is demonstrated. Simultaneously, the 1.25 Gbps
optical on-off-keying (OOK) signal is transmitted at the concentration of
different NaCl solutions, which indicates the bit-error-ratio (BER) decreases
with the increase in concentration. The novel IOSAC technology shows the
potential to realize high-performance simultaneous biosensing and communication
in real time and further accelerate the development of IoT and 6G networks.Comment: 11pages, 5 figutre
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