45 research outputs found
Inductive Relation Prediction from Relational Paths and Context with Hierarchical Transformers
Relation prediction on knowledge graphs (KGs) is a key research topic.
Dominant embedding-based methods mainly focus on the transductive setting and
lack the inductive ability to generalize to new entities for inference.
Existing methods for inductive reasoning mostly mine the connections between
entities, i.e., relational paths, without considering the nature of head and
tail entities contained in the relational context. This paper proposes a novel
method that captures both connections between entities and the intrinsic nature
of entities, by simultaneously aggregating RElational Paths and cOntext with a
unified hieRarchical Transformer framework, namely REPORT. REPORT relies solely
on relation semantics and can naturally generalize to the fully-inductive
setting, where KGs for training and inference have no common entities. In the
experiments, REPORT performs consistently better than all baselines on almost
all the eight version subsets of two fully-inductive datasets. Moreover. REPORT
is interpretable by providing each element's contribution to the prediction
results.Comment: Accepted by ICASSP 2023 (Oral
Not All Image Regions Matter: Masked Vector Quantization for Autoregressive Image Generation
Existing autoregressive models follow the two-stage generation paradigm that
first learns a codebook in the latent space for image reconstruction and then
completes the image generation autoregressively based on the learned codebook.
However, existing codebook learning simply models all local region information
of images without distinguishing their different perceptual importance, which
brings redundancy in the learned codebook that not only limits the next stage's
autoregressive model's ability to model important structure but also results in
high training cost and slow generation speed. In this study, we borrow the idea
of importance perception from classical image coding theory and propose a novel
two-stage framework, which consists of Masked Quantization VAE (MQ-VAE) and
Stackformer, to relieve the model from modeling redundancy. Specifically,
MQ-VAE incorporates an adaptive mask module for masking redundant region
features before quantization and an adaptive de-mask module for recovering the
original grid image feature map to faithfully reconstruct the original images
after quantization. Then, Stackformer learns to predict the combination of the
next code and its position in the feature map. Comprehensive experiments on
various image generation validate our effectiveness and efficiency. Code will
be released at https://github.com/CrossmodalGroup/MaskedVectorQuantization.Comment: accepted by CVPR 202
Image Captioning with Context-Aware Auxiliary Guidance
Image captioning is a challenging computer vision task, which aims to
generate a natural language description of an image. Most recent researches
follow the encoder-decoder framework which depends heavily on the previous
generated words for the current prediction. Such methods can not effectively
take advantage of the future predicted information to learn complete semantics.
In this paper, we propose Context-Aware Auxiliary Guidance (CAAG) mechanism
that can guide the captioning model to perceive global contexts. Upon the
captioning model, CAAG performs semantic attention that selectively
concentrates on useful information of the global predictions to reproduce the
current generation. To validate the adaptability of the method, we apply CAAG
to three popular captioners and our proposal achieves competitive performance
on the challenging Microsoft COCO image captioning benchmark, e.g. 132.2
CIDEr-D score on Karpathy split and 130.7 CIDEr-D (c40) score on official
online evaluation server
Random Entity Quantization for Parameter-Efficient Compositional Knowledge Graph Representation
Representation Learning on Knowledge Graphs (KGs) is essential for downstream
tasks. The dominant approach, KG Embedding (KGE), represents entities with
independent vectors and faces the scalability challenge. Recent studies propose
an alternative way for parameter efficiency, which represents entities by
composing entity-corresponding codewords matched from predefined small-scale
codebooks. We refer to the process of obtaining corresponding codewords of each
entity as entity quantization, for which previous works have designed
complicated strategies. Surprisingly, this paper shows that simple random
entity quantization can achieve similar results to current strategies. We
analyze this phenomenon and reveal that entity codes, the quantization outcomes
for expressing entities, have higher entropy at the code level and Jaccard
distance at the codeword level under random entity quantization. Therefore,
different entities become more easily distinguished, facilitating effective KG
representation. The above results show that current quantization strategies are
not critical for KG representation, and there is still room for improvement in
entity distinguishability beyond current strategies. The code to reproduce our
results is available at https://github.com/JiaangL/RandomQuantization.Comment: Accepted to EMNLP 202
Entity Structure Within and Throughout: Modeling Mention Dependencies for Document-Level Relation Extraction
Entities, as the essential elements in relation extraction tasks, exhibit
certain structure. In this work, we formulate such structure as distinctive
dependencies between mention pairs. We then propose SSAN, which incorporates
these structural dependencies within the standard self-attention mechanism and
throughout the overall encoding stage. Specifically, we design two alternative
transformation modules inside each self-attention building block to produce
attentive biases so as to adaptively regularize its attention flow. Our
experiments demonstrate the usefulness of the proposed entity structure and the
effectiveness of SSAN. It significantly outperforms competitive baselines,
achieving new state-of-the-art results on three popular document-level relation
extraction datasets. We further provide ablation and visualization to show how
the entity structure guides the model for better relation extraction. Our code
is publicly available.Comment: Accepted to AAAI 202
A Bi2Te3-Filled Nickel Foam Film with Exceptional Flexibility and Thermoelectric Performance
The past decades have witnessed surging demand for wearable electronics, for which thermoelectrics (TEs) are considered a promising self-charging technology, as they are capable of converting skin heat into electricity directly. Bi2Te3 is the most-used TE material at room temperature, due to a high zT of ~1. However, it is different to integrate Bi2Te3 for wearable TEs owing to its intrinsic rigidity. Bi2Te3 could be flexible when made thin enough, but this implies a small electrical and thermal load, thus severely restricting the power output. Herein, we developed a Bi2Te3/nickel foam (NiFoam) composite film through solvothermal deposition of Bi2Te3 nanoplates into porous NiFoam. Due to the mesh structure and ductility of Ni Foam, the film, with a thickness of 160 μm, exhibited a high figure of merit for flexibility, 0.016, connoting higher output. Moreover, the film also revealed a high tensile strength of 12.7 ± 0.04 MPa and a maximum elongation rate of 28.8%. In addition, due to the film’s high electrical conductivity and enhanced Seebeck coefficient, an outstanding power factor of 850 μW m−1 K−2 was achieved, which is among the highest ever reported. A module fabricated with five such n-type legs integrated electrically in series and thermally in parallel showed an output power of 22.8 nW at a temperature gap of 30 K. This work offered a cost-effective avenue for making highly flexible TE films for power supply of wearable electronics by intercalating TE nanoplates into porous and meshed-structure materials