arXiv subjects

Xiong Yang

Publications and source records attributed to Xiong Yang.

17 recordsLinked to original sources

arXiv2026

Beyond Placement and Articulation: Usage-Driven Code Scenes for Embodied Interaction

Indoor scene synthesis provides essential environments for embodied AI, robotic manipulation, and simulation-based policy learning. Recent code-based scene generation methods produce editable and extensible environments, yet they remain focused on visual construction and object-level articulation, leaving the functional usage of scenes largely unmodeled. To address this problem, we present RoomWright, an agentic usage-driven framework for generating 3D scenes represented entirely as code for embodied interaction. RoomWright performs usage-driven object reasoning, which treats each anchor as a task centre and admits task-required objects and their affordances. A code agent further enables multi-part interaction by compiling each interaction into a trigger, condition, effect rule that updates structured object states, capturing causal dependencies across objects. Moreover, since manipuland orientation is ambiguous and hard to recover from pixels, RoomWright alleviates this via annotation-informed usage-guided orientation. Extensive experiments demonstrate the effectiveness of our method. The resulting scenes are executable, editable, and simulation-ready, providing interactive environments for embodied AI and policy learning.

cs.RO↗

arXiv2025

A modified RIME algorithm with covariance learning and diversity enhancement for numerical optimization

Metaheuristics are widely applied for their ability to provide more efficient solutions. The RIME algorithm is a recently proposed physical-based metaheuristic algorithm with certain advantages. However, it suffers from rapid loss of population diversity during optimization and is prone to fall into local optima, leading to unbalanced exploitation and exploration. To address the shortcomings of RIME, this paper proposes a modified RIME with covariance learning and diversity enhancement (MRIME-CD). The algorithm applies three strategies to improve the optimization capability. First, a covariance learning strategy is introduced in the soft-rime search stage to increase the population diversity and balance the over-exploitation ability of RIME through the bootstrapping effect of dominant populations. Second, in order to moderate the tendency of RIME population to approach the optimal individual in the early search stage, an average bootstrapping strategy is introduced into the hard-rime puncture mechanism, which guides the population search through the weighted position of the dominant populations, thus enhancing the global search ability of RIME in the early stage. Finally, a new stagnation indicator is proposed, and a stochastic covariance learning strategy is used to update the stagnant individuals in the population when the algorithm gets stagnant, thus enhancing the ability to jump out of the local optimal solution. The proposed MRIME-CD algorithm is subjected to a series of validations on the CEC2017 test set, the CEC2022 test set, and the experimental results are analyzed using the Friedman test, the Wilcoxon rank sum test, and the Kruskal Wallis test. The results show that MRIME-CD can effectively improve the performance of basic RIME and has obvious superiorities in terms of solution accuracy, convergence speed and stability.

cs.NE↗

arXiv2025

An improved educational competition optimizer with multi-covariance learning operators for global optimization problems

The educational competition optimizer is a recently introduced metaheuristic algorithm inspired by human behavior, originating from the dynamics of educational competition within society. Nonetheless, ECO faces constraints due to an imbalance between exploitation and exploration, rendering it susceptible to local optima and demonstrating restricted effectiveness in addressing complex optimization problems. To address these limitations, this study presents an enhanced educational competition optimizer (IECO-MCO) utilizing multi-covariance learning operators. In IECO, three distinct covariance learning operators are introduced to improve the performance of ECO. Each operator effectively balances exploitation and exploration while preventing premature convergence of the population. The effectiveness of IECO is assessed through benchmark functions derived from the CEC 2017 and CEC 2022 test suites, and its performance is compared with various basic and improved algorithms across different categories. The results demonstrate that IECO-MCO surpasses the basic ECO and other competing algorithms in convergence speed, stability, and the capability to avoid local optima. Furthermore, statistical analyses, including the Friedman test, Kruskal-Wallis test, and Wilcoxon rank-sum test, are conducted to validate the superiority of IECO-MCO over the compared algorithms. Compared with the basic algorithm (improved algorithm), IECO-MCO achieved an average ranking of 2.213 (2.488) on the CE2017 and CEC2022 test suites. Additionally, the practical applicability of the proposed IECO-MCO algorithm is verified by solving constrained optimization problems. The experimental outcomes demonstrate the superior performance of IECO-MCO in tackling intricate optimization problems, underscoring its robustness and practical effectiveness in real-world scenarios.

cs.NE↗

arXiv2025

WXSOD: A Benchmark for Robust Salient Object Detection in Adverse Weather Conditions

Salient object detection (SOD) in complex environments remains a challenging research topic. Most existing methods perform well in natural scenes with negligible noise, and tend to leverage multi-modal information (e.g., depth and infrared) to enhance accuracy. However, few studies are concerned with the damage of weather noise on SOD performance due to the lack of dataset with pixel-wise annotations. To bridge this gap, this paper introduces a novel Weather-eXtended Salient Object Detection (WXSOD) dataset. It consists of 14,945 RGB images with diverse weather noise, along with the corresponding ground truth annotations and weather labels. To verify algorithm generalization, WXSOD contains two test sets, i.e., a synthesized test set and a real test set. The former is generated by adding weather noise to clean images, while the latter contains real-world weather noise. Based on WXSOD, we propose an efficient baseline, termed Weather-aware Feature Aggregation Network (WFANet), which adopts a fully supervised two-branch architecture. Specifically, the weather prediction branch mines weather-related deep features, while the saliency detection branch fuses semantic features extracted from the backbone with weather features for SOD. Comprehensive comparisons against 17 SOD methods shows that our WFANet achieves superior performance on WXSOD. The code and benchmark results will be made publicly available at https://github.com/C-water/WXSOD

cs.CV↗

arXiv2025

Memory-updated-based Framework for 100% Reliable Flexible Flat Cables Insertion

Automatic assembly lines have increasingly replaced human labor in various tasks; however, the automation of Flexible Flat Cable (FFC) insertion remains unrealized due to its high requirement for effective feedback and dynamic operation, limiting approximately 11% of global industrial capacity. Despite lots of approaches, like vision-based tactile sensors and reinforcement learning, having been proposed, the implementation of human-like high-reliable insertion (i.e., with a 100% success rate in completed insertion) remains a big challenge. Drawing inspiration from human behavior in FFC insertion, which involves sensing three-dimensional forces, translating them into physical concepts, and continuously improving estimates, we propose a novel framework. This framework includes a sensing module for collecting three-dimensional tactile data, a perception module for interpreting this data into meaningful physical signals, and a memory module based on Bayesian theory for reliability estimation and control. This strategy enables the robot to accurately assess its physical state and generate reliable status estimations and corrective actions. Experimental results demonstrate that the robot using this framework can detect alignment errors of 0.5 mm with an accuracy of 97.92% and then achieve a 100% success rate in all completed tests after a few iterations. This work addresses the challenges of unreliable perception and control in complex insertion tasks, highlighting the path toward the development of fully automated production lines.

cs.RO↗

arXiv2024

Synergistic Interface Effects in Composite Dielectrics: Insights into Charge Trapping Regulation through Multiscale Modeling

The rapid development of modern energy applications drives an urgent need to enhance the dielectric strength of energy storage dielectrics for higher power density. Interface design is a promising strategy to regulate the crucial charge transport process determining dielectric strength. However, the targeted exploitation of interface effects on charge transport is limited due to a lack of fundamental understanding of the underlying mechanisms involving elementary electronic processes and details of the intricate interplay of characteristics of molecular building blocks and the interfacial morphology -- details that cannot fully be resolved with experimental methods. Here we employ a multiscale modeling approach linking the quantum properties of the charge carriers with nano- and mesoscale structural details of complex interfaces. Applied to a prototypical application-proven cellulose-oil composite with interfaces formed between oil, disordered, and crystalline cellulose regions, this approach demonstrates that charges are trapped in the disordered region. Specifically, it unveils this trapping as a synergistic effect of two transport-regulating interface mechanisms: back-transfer to the oil region is suppressed by energetic factors, while forward-transfer to the crystalline cellulose is suppressed by low electronic coupling. The insight into the molecular origins of interface effects via dual-interface regulation offers new development paths for advanced energy materials.

cond-mat.mtrl-sci↗

arXiv2024

Real-time Multi-view Omnidirectional Depth Estimation for Real Scenarios based on Teacher-Student Learning with Unlabeled Data

Omnidirectional depth estimation enables efficient 3D perception over a full 360-degree range. However, in real-world applications such as autonomous driving and robotics, achieving real-time performance and robust cross-scene generalization remains a significant challenge for existing algorithms. In this paper, we propose a real-time omnidirectional depth estimation method for edge computing platforms named Rt-OmniMVS, which introduces the Combined Spherical Sweeping method and implements the lightweight network structure to achieve real-time performance on edge computing platforms. To achieve high accuracy, robustness, and generalization in real-world environments, we introduce a teacher-student learning strategy. We leverage the high-precision stereo matching method as the teacher model to predict pseudo labels for unlabeled real-world data, and utilize data and model augmentation techniques for training to enhance performance of the student model Rt-OmniMVS. We also propose HexaMODE, an omnidirectional depth sensing system based on multi-view fisheye cameras and edge computation device. A large-scale hybrid dataset contains both unlabeled real-world data and synthetic data is collected for model training. Experiments on public datasets demonstrate that proposed method achieves results comparable to state-of-the-art approaches while consuming significantly less resource. The proposed system and algorithm also demonstrate high accuracy in various complex real-world scenarios, both indoors and outdoors, achieving an inference speed of 15 frames per second on edge computing platforms.

cs.CV↗

arXiv2024

F3T: A soft tactile unit with 3D force and temperature mathematical decoupling ability for robots

The human skin exhibits remarkable capability to perceive contact forces and environmental temperatures, providing intricate information essential for nuanced manipulation. Despite recent advancements in soft tactile sensors, a significant challenge remains in accurately decoupling signals - specifically, separating force from directional orientation and temperature - resulting in fail to meet the advanced application requirements of robots. This research proposes a multi-layered soft sensor unit (F3T) designed to achieve isolated measurements and mathematical decoupling of normal pressure, omnidirectional tangential forces, and temperature. We developed a circular coaxial magnetic film featuring a floating-mountain multi-layer capacitor, facilitating the physical decoupling of normal and tangential forces in all directions. Additionally, we incorporated an ion gel-based temperature sensing film atop the tactile sensor. This sensor is resilient to external pressure and deformation, enabling it to measure temperature and, crucially, eliminate capacitor errors induced by environmental temperature changes. This innovative design allows for the decoupled measurement of multiple signals, paving the way for advancements in higher-level robot motion control, autonomous decision-making, and task planning.

cs.RO↗

arXiv2023

An alternative simulation approach for surface flashover in vacuum using a 1D2V continuum and kinetic model

Surface flashover across insulator in vacuum is a destructive plasma discharge which undermines the behaviors of a range of applications in electrical engineering, particle physics, space engineering, etc. This phenomenon is widely modeled by the particle-in-cell (PIC) simulation, here the continuum and kinetic simulation method is first proposed and implemented as an alternative solution for flashover modeling, aiming for the prevention of the unfavorable particle noises in PIC models. The 1D2V (one dimension in space, two dimensions in velocity) kinetic simulation model is constructed. Modeling setup, physical assumptions, and simulation algorithm are presented in detail, and a comparison with the well-known secondary electron emission avalanche (SEEA) analytical expression and existing PIC simulation is made. Obtained kinetic simulation results are consistent with the analytical prediction, and feature noise-free data of surface charge density as well as particle fluxes of primary and secondary electrons. Discrepancies between the two simulation models and analytical predictions are explained. The code is convenient for updating to include additional physical processes, and possible implementations of outgassing and extra plasma species for final breakdown stage are discussed. The proposed continuum and kinetic approach is expected to inspire future flashover modeling studies for the understanding and mitigation.

physics.plasm-ph↗

arXiv2018

Vortex lattice and vortex bound states in CsFe$_2$As$_2$ investigated by scanning tunneling microscopy/spectroscopy

We investigate the vortex lattice and vortex bound states in CsFe$_2$As$_2$ single crystals by scanning tunneling microscopy/spectroscopy (STM/STS) under various magnetic fields. A possible structural transition or crossover of vortex lattice is observed with the increase of magnetic field, i.e., the vortex lattice changes from a distorted hexagonal lattice to a distorted tetragonal one at the magnetic field near 0.5 T. It is found that a mixture of stripelike hexagonal and square vortex lattices emerges in the crossover region. The vortex bound state is also observed in the vortex center. The tunneling spectra crossing a vortex show that the bound-state peak position holds near zero bias with STM tip moving away from the vortex core center. The Fermi energy estimated from the vortex bound state energy is very small. Our investigations provide experimental information to both the vortex lattice and the vortex bound states in this iron-based superconductor.

cond-mat.supr-con↗

arXiv2018

Sign reversal superconducting gaps revealed by phase referenced quasi-particle interference of impurity induced bound states in (Li$_{1-x}$Fe$_x$)OHFe$_{1-y}$Zn$_y$Se

By measuring the spatial distribution of differential conductance near impurities on Fe sites, we have obtained the quasi-particle interference (QPI) patterns in the (Li$_{1-x}$Fe$_x$)OHFe$_{1-y}$Zn$_y$Se superconductor with only electron Fermi surfaces. By taking the Fourier transform on these patterns, we investigate the scattering features between the two circles of electron pockets formed by folding or hybridization. We treat the data by using the recent theoretical approach [arXiv:1710.09089] which is specially designed for the impurity induced bound states. It is found that the superconducting gap sign is reversed on the two electron pockets, which can be directly visualized by the phase-referenced QPI technique, indicating that the Cooper pairing is induced by the repulsive interaction. Our results further show that this method is also applicable for data measured for multiple impurities, which provides an easy and feasible way for detecting the gap function of unconventional superconductors.

cond-mat.supr-con↗

arXiv2017

Experimental Demonstration of the Sign Reversal of the Order Parameter in (Li1-xFex)OHFe1-yZnySe

Iron pnictides are the only known family of unconventional high-temperature superconductors besides cuprates. Until recently, it was widely accepted that superconductivity is spin-fluctuation driven and intimately related to their fermiology, specifically, hole and electron pockets separated by the same wave vector that characterizes the dominant spin fluctuations, and supporting order parameters (OP) of opposite signs. This picture was questioned after the discovery of a new family, based on the FeSe layers, either intercalated or in the monolayer form. The critical temperatures there reach ~40 K, the same as in optimally doped bulk FeSe - despite the fact that intercalation removes the hole pockets from the Fermi level and, seemingly, undermines the basis for the spin-fluctuation theory and the idea of a sign-changing OP. In this paper, using the recently proposed phase-sensitive quasiparticle interference technique, we show that in LiOH intercalated FeSe compound the OP does change sign, albeit within the electronic pockets, and not between the hole and electron ones. This result unifies the pairing mechanism of iron based superconductors with or without the hole Fermi pockets and supports the conclusion that spin fluctuations play the key role in electron pairing.

cond-mat.supr-con↗

arXiv2016

Strong coupling superconductivity revealed by scanning tunneling microscope in tetragonal FeS

We investigate the electronic properties of the tetragonal FeS superconductor by using scanning tunneling microscope/spectroscopy. It is found that the typical tunneling spectrum on the top layer of sulfur can be nicely fitted with an anisotropic s-wave or a combination of two superconducting components in which one may have a highly anisotropic or nodal like superconducting gap. The fittings lead to the maximum superconducting gap $Δ_{max}\approx$ 0.90$\;$meV, which yields a ratio of 2$Δ_{max}/k_BT_c\approx$ 4.65. This value is larger than that of the predicted value 3.53 by the BCS theory in the weak coupling limit, indicating a strong coupling superconductivity. Two kinds of defects are observed on the surface, which can be assigned to the defects on the S sites (four-fold image) and Fe sites (dumbbell shape). Impurity induced resonance states are found only for the former defects and stay at zero-bias energy.

cond-mat.supr-con↗

arXiv2016

Drive the Dirac Electrons into Cooper Pairs in SrxBi2Se3

Topological superconductor is a very interesting and frontier topic in condensed matter physics1. Despite the tremendous efforts in exploring the topological superconductivity, its presence is however still under heavy debates. The Dirac electrons are supposed to exist in a thin layer of the surface of a topological insulator. Due to the finite spin-orbital coupling, these electrons will have a spin-momentum locking effect. In this case, the superfluid with the spin singlet Cooper pairing is not completely comforted by the Dirac electrons. It thus remains unclear whether and how the Dirac electrons fall into Cooper pairing in an intrinsic superconductor with the topological surface states. In this work, we show the systematic study of scanning tunneling microscope/spectroscopy on the possible topological superconductor SrxBi2Se3. We first show that only the intercalated (or inserted), not the substituted Sr atoms can induce superconductivity. Then we show the full superconducting gaps without any abnormal in-gap density of states as expected theoretically for the bulk topological superconductivity. However, we find that the surface Dirac electrons will simultaneously condense into the superconducting state when the energy is smaller than the bulk superconducting gap. This vividly demonstrates how the surface Dirac electrons are driven into Cooper pairs.

cond-mat.supr-con↗

arXiv2016

Possible superconducting fluctuation and pseudogap state above $T_c$ in CsFe$_2$As$_2$

Resistive, magnetization, torque, specific heat and scanning tunneling microscopy measurements are carried out on the hole heavily doped CsFe$_2$As$_2$ single crystals. A characteristic temperature $T^*\sim13$ K, which is several times higher than the superconducting transition temperature $T_c=2.15$ K, is observed and possibly related to the superconducting fluctuation or the pseudogap state. A diamagnetic signal detected by torque measurements starts from the superconducting state, keeps finite and vanishes gradually until a temperature near $T^*$. Temperature dependent resistivity and specific heat also show kinks near $T^*$. An asymmetric gap-like feature with the energy of 8.4 meV and a symmetric superconducting related gap of 2.2 meV on the scanning tunneling spectra are detected, and these pseudogap-related features disappear at temperatures up to at least 9 K. These observations by different experimental tools suggest the possible existence of superconducting fluctuation or pseudogap state in the temperature range up to 4 - 6 times of $T_c$ in CsFe$_2$As$_2$.

cond-mat.supr-con↗

arXiv2015

Merging Dirac electrons and correlation effect in the heterostructured Bi2Te3/Fe1+dTe

The topological insulator and strong electronic correlation effect are two important subjects in the frontier studies of modern condensed matter physics. A topological insulator exhibits a unique pair of surface conduction bands with the Dirac dispersion albeit the bulk insulating behaviour. These surface states are protected by the topological order, and thus the spin and momentum of these surface electrons are locked together demonstrating the feature of time reversal invariance. On the other hand, the electronic correlation effect becomes the very base of many novel electronic states, such as high temperature superconductivity, giant magnetoresistance etc. Here we report the discovery of merging the two important components: Dirac electrons and the correlation effect in heterostructured Bi2Te3/Fe1+dTe. By measuring the scanning tunneling spectroscopy on Bi2Te3 thin films (a typical topological insulator) thicker than 6 quintuple layers on top of the Fe1+dTe single crystal (a parent phase of the iron based superconductors FeSe1-xTex), we observed the quantum oscillation of Landau levels of the Dirac electrons and the gapped feature at the Fermi energy due to the correlation effect of Fe1+dTe. Our observation challenges the ordinary understandings and must demonstrate some unexplored territory concerning the combination of topological insulator and strong correlation effect.

cond-mat.str-el↗

arXiv2015

Scrutinizing the double superconducting gaps and strong coupling pairing in (Li1-xFexOH)FeSe

In the iron based superconductors, one of the on-going frontier studies is about the pairing mechanism. The recent interest concerns the high temperature superconductivity and its intimate reason in the monolayer FeSe thin films. The challenge here is how the double superconducting gaps seen by the scanning tunnelling spectroscopy (STS) associate however to only one set of Fermi pockets seen by the angle resolved photoemission spectroscopy (ARPES). The recently discovered (Li1-xFexOH)FeSe phase with Tc=40 K provides a good platform to check the fundamental problems. Here we report the STS study on the (Li1-xFexOH)FeSe single crystals. The STS spectrum clearly indicates the presence of double anisotropic gaps with maximum magnitudes of Delta_1=14.3 meV and Delta_2=8.6 meV, and mimics that of the monolayer FeSe thin film. Further analysis based on the quasiparticle interference (QPI) allows us to rule out the d-wave gap, and for the first time assign the larger (smaller) gap to the outer (inner) hybridized Fermi pockets associating with the dxy (dxz/dyz) orbitals, respectively. The huge value Delta_1/k_BT_c = 8.7 discovered here undoubtedly proves the strong coupling mechanism in the present superconducting system.

cond-mat.supr-con↗