refinement stage
KGQuest: Template-Driven QA Generation from Knowledge Graphs with LLM-Based Refinement
Nayab, Sania, Simoni, Marco, Rossolini, Giulio, Saracino, Andrea
The generation of questions and answers (QA) from knowledge graphs (KG) plays a crucial role in the development and testing of educational platforms, dissemination tools, and large language models (LLM). However, existing approaches often struggle with scalability, linguistic quality, and factual consistency. This paper presents a scalable and deterministic pipeline for generating natural language QA from KGs, with an additional refinement step using LLMs to further enhance linguistic quality. The approach first clusters KG triplets based on their relations, creating reusable templates through natural language rules derived from the entity types of objects and relations. A module then leverages LLMs to refine these templates, improving clarity and coherence while preserving factual accuracy. Finally, the instantiation of answer options is achieved through a selection strategy that introduces distractors from the KG. Our experiments demonstrate that this hybrid approach efficiently generates high-quality QA pairs, combining scalability with fluency and linguistic precision.
Coarse-to-fine Animal Pose and Shape Estimation: Supplementary Material
We compare our coarse-to-fine approach with the test-time optimization approach. The refinement stage of our approach relies on the output of the coarse estimation stage as an initial point. We test the sensitivity of our model to the first stage results by adding Gaussian noise to the SMAL and camera parameters estimated from the coarse estimation stage, respectively. We show more qualitative results in Figure 1. Table 2: Adding Gaussian noise to the estimated SMAL parameters (a) and camera parameter (b).
DreamGrasp: Zero-Shot 3D Multi-Object Reconstruction from Partial-View Images for Robotic Manipulation
Kim, Young Hun, Kim, Seungyeon, Lee, Yonghyeon, Park, Frank Chongwoo
Robot tasks such as target-driven manipulation and 3D spatial reasoning - like collision avoidance and path planning - require the ability to reconstruct the 3D geometry of objects and identify object instances from visual observations. While many existing methods rely on accurate depth [1, 2] or all-around-view RGB images [3, 4, 5], we address a more practical setting: reconstruction from only sparse, partial-view RGB images (e.g., as few as two). This direction is crucial for real-world deployment, where depth sensing often fails for transparent or reflective objects, and full 360 scene coverage is rarely available due to occlusions in cluttered environments or the limited workspace of a robot. Recent approaches address this challenge by employing supervised learning on datasets of partial observations paired with complete scenes [6, 7]. However, the performance of these supervised learning approaches is inherently constrained by the diversity of the datasets. This highlights the need for alternative approaches that can generalize more robustly beyond the constraints of curated 3D training data. We draw inspiration from recent findings that large-scale image generative models - when suitably fine-tuned with datasets of paired camera poses and images - can produce reasonable predictions of unseen parts of a scene (e.g., the backs of objects) given a partial-view image as input [8, 9, 10, 11, 12, 13, 14]. However, prior works demonstrate strong performance only on clean, front-view images of single, unoccluded objects, and often struggle in multi-object scenarios where objects heavily occlude one another - which are prevalent in robotic object manipulation tasks. Our key idea is to first reconstruct a coarse 3D geometry from partial-view images, and then segment multiple objects into individual instances - where we adopt the recent contrastive lifting algoarXiv:2507.05627v1
De-AntiFake: Rethinking the Protective Perturbations Against Voice Cloning Attacks
Fan, Wei, Chen, Kejiang, Liu, Chang, Zhang, Weiming, Yu, Nenghai
The rapid advancement of speech generation models has heightened privacy and security concerns related to voice cloning (VC). Recent studies have investigated disrupting unauthorized voice cloning by introducing adversarial perturbations. However, determined attackers can mitigate these protective perturbations and successfully execute VC. In this study, we conduct the first systematic evaluation of these protective perturbations against VC under realistic threat models that include perturbation purification. Our findings reveal that while existing purification methods can neutralize a considerable portion of the protective perturbations, they still lead to distortions in the feature space of VC models, which degrades the performance of VC. From this perspective, we propose a novel two-stage purification method: (1) Purify the perturbed speech; (2) Refine it using phoneme guidance to align it with the clean speech distribution. Experimental results demonstrate that our method outperforms state-of-the-art purification methods in disrupting VC defenses. Our study reveals the limitations of adversarial perturbation-based VC defenses and underscores the urgent need for more robust solutions to mitigate the security and privacy risks posed by VC. The code and audio samples are available at https://de-antifake.github.io.
FLoE: Fisher-Based Layer Selection for Efficient Sparse Adaptation of Low-Rank Experts
Wang, Xinyi, Gao, Lirong, Wang, Haobo, Zhang, Yiming, Zhao, Junbo
Parameter-Efficient Fine-Tuning (PEFT) methods have emerged as a widely adopted strategy for adapting pre-trained Large Language Models (LLMs) to downstream tasks, significantly reducing memory and computational costs. However, most existing PEFT techniques uniformly deploy LoRA adapters across all layers, disregarding the intrinsic heterogeneity of layer contributions and task-specific rank requirements. This uniform paradigm leads to redundant parameter allocation and suboptimal adaptation efficiency. To address these limitations, we propose FLoE, a novel PEFT framework that introduces two key innovations: (i) a Fisher information-guided importance scoring mechanism to dynamically identify task-critical transformer layers for MoE-based low-rank adaptation, enabling sparse adapter deployment; and (ii) a Bayesian optimization-driven rank allocator that automatically determines optimal LoRA ranks on specific datasets without exhaustive grid search. Extensive experiments across diverse LLMs and benchmarks reveal that FLoE achieves impressive efficiency-accuracy trade-offs, making FLoE particularly advantageous in resource-constrained environments that necessitate rapid adaptation.
Stage-Wise and Prior-Aware Neural Speech Phase Prediction
Liu, Fei, Ai, Yang, Du, Hui-Peng, Lu, Ye-Xin, Zheng, Rui-Chen, Ling, Zhen-Hua
This paper proposes a novel Stage-wise and Prior-aware Neural Speech Phase Prediction (SP-NSPP) model, which predicts the phase spectrum from input amplitude spectrum by two-stage neural networks. In the initial prior-construction stage, we preliminarily predict a rough prior phase spectrum from the amplitude spectrum. The subsequent refinement stage transforms the amplitude spectrum into a refined high-quality phase spectrum conditioned on the prior phase. Networks in both stages use ConvNeXt v2 blocks as the backbone and adopt adversarial training by innovatively introducing a phase spectrum discriminator (PSD). To further improve the continuity of the refined phase, we also incorporate a time-frequency integrated difference (TFID) loss in the refinement stage. Experimental results confirm that, compared to neural network-based no-prior phase prediction methods, the proposed SP-NSPP achieves higher phase prediction accuracy, thanks to introducing the coarse phase priors and diverse training criteria. Compared to iterative phase estimation algorithms, our proposed SP-NSPP does not require multiple rounds of staged iterations, resulting in higher generation efficiency.
Automatic Spatial Calibration of Near-Field MIMO Radar With Respect to Optical Sensors
Wirth, Vanessa, Bräunig, Johanna, Khouri, Danti, Gutsche, Florian, Vossiek, Martin, Weyrich, Tim, Stamminger, Marc
Despite an emerging interest in MIMO radar, the utilization of its complementary strengths in combination with optical sensors has so far been limited to far-field applications, due to the challenges that arise from mutual sensor calibration in the near field. In fact, most related approaches in the autonomous industry propose target-based calibration methods using corner reflectors that have proven to be unsuitable for the near field. In contrast, we propose a novel, joint calibration approach for optical RGB-D sensors and MIMO radars that is designed to operate in the radar's near-field range, within decimeters from the sensors. Our pipeline consists of a bespoke calibration target, allowing for automatic target detection and localization, followed by the spatial calibration of the two sensor coordinate systems through target registration. We validate our approach using two different depth sensing technologies from the optical domain. The experiments show the efficiency and accuracy of our calibration for various target displacements, as well as its robustness of our localization in terms of signal ambiguities.
TerrainMesh: Metric-Semantic Terrain Reconstruction from Aerial Images Using Joint 2D-3D Learning
Feng, Qiaojun, Atanasov, Nikolay
Abstract--This paper considers outdoor terrain mapping using RGB images obtained from an aerial vehicle. While feature-based localization and mapping techniques deliver real-time vehicle odometry and sparse keypoint depth reconstruction, a dense model of the environment geometry and semantics (vegetation, buildings, etc.) is usually recovered offline with significant computation and storage. This paper develops a joint 2D-3D learning approach to reconstruct a local metric-semantic mesh at each camera keyframe maintained by a visual odometry algorithm. Given the estimated camera trajectory, the local meshes can be assembled into a global environment model to capture the terrain topology and semantics during online operation. A local mesh is reconstructed using an initialization and refinement stage. In the initialization stage, we estimate the mesh vertex elevation by solving a least squares problem relating the vertex barycentric coordinates to the sparse keypoint depth measurements. In the refinement stage, we associate 2D image and semantic features with the 3D mesh vertices using camera projection and apply graph convolution to refine the mesh vertex spatial coordinates and semantic features based on joint 2D and 3D supervision. Quantitative and qualitative evaluation using real aerial images show the potential of our method to support environmental monitoring and surveillance applications. The color, elevation, and semantics of the mesh are visualized in the top-right, bottom-left and bottom-right plots. However, range sensors and, hence, dense robot systems to impact environmental monitoring, security depth information are not available during outdoor flight. This paper considers While specialized sensors and algorithms exist for real-time the problem of building a metric-semantic terrain model, dense stereo matching, they are restricted to a limited depth represented as a triangular mesh, of an outdoor environment range, much smaller than the distances commonly present using a sequence of overhead RGB images obtained onboard a in aerial images. Moreover, due to limited depth variation, UAV. Figure 1 shows an example input and mesh reconstruction. Recently, images, where the depth variation is small compared to the there has also been increasing interest in supplementing absolute depth values.
Novel OCT mosaicking pipeline with Feature- and Pixel-based registration
Wang, Jiacheng, Li, Hao, Hu, Dewei, Tao, Yuankai K., Oguz, Ipek
High-resolution Optical Coherence Tomography (OCT) images are crucial for ophthalmology studies but are limited by their relatively narrow field of view (FoV). Image mosaicking is a technique for aligning multiple overlapping images to obtain a larger FoV. Current mosaicking pipelines often struggle with substantial noise and considerable displacement between the input sub-fields. In this paper, we propose a versatile pipeline for stitching multi-view OCT/OCTA \textit{en face} projection images. Our method combines the strengths of learning-based feature matching and robust pixel-based registration to align multiple images effectively. Furthermore, we advance the application of a trained foundational model, Segment Anything Model (SAM), to validate mosaicking results in an unsupervised manner. The efficacy of our pipeline is validated using an in-house dataset and a large public dataset, where our method shows superior performance in terms of both accuracy and computational efficiency. We also made our evaluation tool for image mosaicking and the corresponding pipeline publicly available at \url{https://github.com/MedICL-VU/OCT-mosaicking}.
Automatic Truss Design with Reinforcement Learning
Du, Weihua, Zhao, Jinglun, Yu, Chao, Yao, Xingcheng, Song, Zimeng, Wu, Siyang, Luo, Ruifeng, Liu, Zhiyuan, Zhao, Xianzhong, Wu, Yi
Truss layout design, namely finding a lightweight truss layout satisfying all the physical constraints, is a fundamental problem in the building industry. Generating the optimal layout is a challenging combinatorial optimization problem, which can be extremely expensive to solve by exhaustive search. Directly applying end-to-end reinforcement learning (RL) methods to truss layout design is infeasible either, since only a tiny portion of the entire layout space is valid under the physical constraints, leading to particularly sparse rewards for RL training. In this paper, we develop AutoTruss, a two-stage framework to efficiently generate both lightweight and valid truss layouts. AutoTruss first adopts Monte Carlo tree search to discover a diverse collection of valid layouts. Then RL is applied to iteratively refine the valid solutions. We conduct experiments and ablation studies in popular truss layout design test cases in both 2D and 3D settings. AutoTruss outperforms the best-reported layouts by 25.1% in the most challenging 3D test cases, resulting in the first effective deep-RL-based approach in the truss layout design literature.