- Research Article
- 10.1016/j.orl.2026.107431
Parallel Graver basis extraction for nonlinear integer optimization
- Jul 01, 2026
- Operations Research Letters
- Wenbo Liu + 2 more +2
Publications from 2021 to 2026
Showing 10 of 264 papers
Parallel Graver basis extraction for nonlinear integer optimization
Empirical and Machine Learning Forecasting for Offline Retail: Nonlinear Weather Effects and Heterogeneity
LungNoduleAgent: A Collaborative Multi-Agent System for Precision Diagnosis of Lung Nodules
Diagnosing lung cancer typically involves physicians identifying lung nodules in Computed tomography (CT) scans and generating diagnostic reports based on their morphological features and medical expertise. Although advancements have been made in using multimodal large language models for analyzing lung CT scans, challenges remain in accurately describing nodule morphology and incorporating medical expertise. These limitations affect the reliability and effectiveness of these models in clinical settings. Collaborative multi-agent systems offer a promising strategy for achieving a balance between generality and precision in medical applications, yet their potential in pathology has not been thoroughly explored. To bridge these gaps, we introduce LungNoduleAgent, an innovative collaborative multi-agent system specifically designed for analyzing lung CT scans. LungNoduleAgent streamlines the diagnostic process into sequential components, improving precision in describing nodules and grading malignancy through three primary modules. The first module, the Nodule Spotter, coordinates clinical detection models to accurately identify nodules. The second module, the Radiologist, integrates localized image description techniques to produce comprehensive CT reports. Finally, the Doctor Agent System performs malignancy reasoning by using images and CT reports, supported by a pathology knowledge base and a multi-agent system framework. Extensive testing on two private datasets and the public LIDC-IDRI dataset indicates that LungNoduleAgent surpasses mainstream vision-language models, agent systems, and advanced expert models such as GPT-4o, Claude 3.7 Sonnet, LLaMA-3.2 Vision, Qwen2.5-VL, Med-R1, MedGemma, MedAgent-Pro, MedAgents, MDAgent and LLaVA-Med. These results highlight the importance of region-level semantic alignment and multi-agent collaboration in diagnosing nodules. LungNoduleAgent stands out as a promising foundational tool for supporting clinical analyses of lung nodules.
Read moreSegmentation-guided multi-modal brain tumors survival prediction model using pseudo-labeling approach.
Improved Alzheimer’s disease diagnosis using multimodal sparse similarity feature selection and auxiliary data
A robust and stable phase field method for structural topology optimization
Training-Free Breast Ultrasound Image Segmentation With Retrieval-Based SAM2.
Early detection and treatment are crucial for improving the prognosis of breast cancer. While ultrasound imaging is widely utilized for screening, its interpretation is subjective and heavily dependent on clinician expertise. Although supervised models have shown great promise in medical image segmentation, they encounter challenges such as the need for large labeled datasets, extended training times, and limited generalization to external datasets. We propose TFSeg, a Training-Free automatic image segmentation framework based on Segment Anything Model 2 (SAM2). TFSeg eliminates the need for re-training new models and tuning hyper-parameters by generating image sequences through the retrieval of the top-k most similar images from the training set, using their mask prompts to guide SAM2 in achieving accurate and efficient segmentation. Our approach, validated on a breast ultrasound image dataset, achieved a Dice score of 82.66%, surpassing the performance of most supervised and training-free segmentation models. Notably, it achieved the highest precision (87.93%) among all the compared methods. By combining image retrieval with sequence generation, TFSeg leverages SAM2 to provide an efficient and effective solution for breast cancer ultrasound image segmentation and demonstrates potential for broader applications in medical image analysis. The Training-Free automatic image Segmentation framework addresses challenges associated with supervised models, making it a promising method for improving breast cancer diagnosis.
Read moreOver-the-Air Adversarial Attacks and Detection for Automatic Speaker Verification
Automatic Speaker Verification (ASV) systems are widely used for voice-based identity verification, but recent studies have shown that they are vulnerable to both over-the-line (OTL) and over-the-air (OTA) adversarial attacks. Although various detection methods have been proposed, their robustness against diverse OTA attack scenarios has not been systematically assessed. In this work, we present AdvSV 2.0, a large-scale, open-source dataset for adversarial attacks on ASV systems. AdvSV 2.0 contains 628k utterances (800 hours) spanning 8 ASV models, 4 attack methods, and 9 physical playback-recording device combinations, and includes both OTL and OTA adversarial examples. To better connect digital adversarial optimization with the physical OTA channel, we further propose an OTA attack generation method based on a Neural Replay Simulator (NRS), which simulates replay-channel distortions and improves OTA attack success rates by up to 33.4% after air transmission. To defend against these attacks, we propose CODA-OCC, a COntrastive Domain-Aligned One-Class Classifier. Built on a one-class classification paradigm, CODA-OCC is trained only on bona fide speech and does not rely on any white-box assumption about the ASV backend. Experimental results on AdvSV 2.0 show that CODA-OCC achieves an EER of 11.2% and an AUC of 0.95, outperforming the purification-based baseline by 8.6% absolute EER, and providing a robust foundation for studying OTA adversarial robustness in ASV.
Read moreBalancing Efficiency and Restoration: Lightweight Mamba-Based Model for CT Metal Artifact Reduction
In computed tomography imaging, metal implants frequently generate severe artifacts that compromise image quality and hinder diagnostic accuracy. There are three main challenges in the existing methods: the deterioration of organ and tissue structures, dependence on sinogram data, and an imbalance between resource use and restoration efficiency. Addressing these issues, we introduce MARMamba, which effectively eliminates artifacts caused by metals of different sizes while maintaining the integrity of the original anatomical structures of the image. Furthermore, this model only focuses on CT images affected by metal artifacts, thus negating the requirement for additional input data. The model is a streamlined UNet architecture, which incorporates multi-scale Mamba (MS-Mamba) as its core module. Within MS-Mamba, a flip mamba block captures comprehensive contextual information by analyzing images from multiple orientations. Subsequently, the average maximum feed-forward network integrates critical features with average features to suppress the artifacts. This combination allows MARMamba to reduce artifacts efficiently. The experimental results demonstrate that our model excels in reducing metal artifacts, offering distinct advantages over other models. It also strikes an optimal balance between computational demands, memory usage, and the number of parameters, highlighting its practical utility in the real world. The code of the presented model is available at: https://github.com/RICKand-MORTY/MARMamba.
Read moreOptimal and Robust Beamforming Design for Digital Semantic Communication System Under QoS Constraints