检索结果-内蒙古大学图书馆

Boundary-aware dynamic re-weighting for semi-supervised medial image segmentation

Expert Systems with Applications 2025年 287卷

作者： Jiang, Weili Li, Jiawen Li, Yihao Wei, Xifei Huang, Jianping Quellec, Gwenolé Si, Weixin Ou, Chubin School of Computing and Artificial Intelligence Southwest Jiaotong University Sichuan Chengdu China Norla Institute of Technical Physics Chengdu China United Imaging Healthcare Shanghai China Weizhi Meditech Co. Ltd. Guangdong Foshan China LaTIM UMR 1101 Inserm Brest France Faculty of Computer Science and Control Engineering Shenzhen University of Advanced Technology China Guangdong General Hospital Guangdong Guangzhou China

Different from traditional semi-supervised learning (SSL), semi-supervised medical image segmentation faces two significant challenges: (1) the imbalanced distribution of labeled data causes models to bias towards majority classes;(2) the distribution discrepancy between labeled and unlabeled samples induces confirmation bias in pseudo-labels. Inspired by clinical practice, where experienced doctors utilize intrinsic features from the interior of target organs to clarify ambiguous boundaries and focus on minority classes, we propose a novel boundary-aware dynamic re-weighting network (BDRN). First, we utilize edge filters to generate visually different but semantically aligned views, compelling two sub-networks to learn informative features from organ interiors and boundaries, respectively. Second, we extract the boundary and interior regions using morphological operators and introduce a shape constraint to enhance feature learning. Additionally, a conflict-adversarial module promotes segmentation consistency between different views. Finally, we propose a dynamic re-weighting strategy based on the effective number to improve attention to imbalanced classes. Experiments demonstrate that our method significantly improves segmentation performance, achieving state-of-the-art results on CT and MR images. Ablation studies further confirm the efficacy of boundary consistency constraints and dynamic re-weighting. The segmentation Dice score for minority organs (e.g., esophagus) on the Synapse dataset is improved by 17.1 %, 46.2 %, and 49.4 % using 10 %, 20 %, and 40 % labeled data, respectively. © 2025 Elsevier Ltd

关键词： Semantic Segmentation

来源：评论

学校读者我要写书评

暂无评论

Fast ORB-SLAM without Keypoint Descriptors

arXiv

引用

arXiv 2020年

作者： Fu, Qiang Yu, Hongshan Wang, Xiaolong Yang, Zhengeng He, Yong Zhang, Hong Mian, Ajmal The National Engineering Laboratory for Robot Visual Perception and Control Technology College of Electrical and Information Engineering Hunan University China The Department of Computing Science University of Alberta Canada Quanzhou Institute of Industrial Design and Machine Intelligence Innovation Hunan University China The Southern University of Science and Technology Shenzhen China The School of Mathematics and Information Science Shaanxi Normal University China The Department of Computer Science The University of Western Australia WA6009 Australia

Indirect methods for visual SLAM are gaining popularity due to their robustness to environmental variations. ORB-SLAM2 [1] is a benchmark method in this domain, however, it consumes significant time for computing descriptors that never get reused unless a frame is selected as a keyframe. To overcome these problems, we present FastORB-SLAM which is light-weight and efficient as it tracks keypoints between adjacent frames without computing descriptors. To achieve this, a two stage descriptor-independent keypoint matching method is proposed based on sparse optical flow. In the first stage, we predict initial keypoint correspondences via a simple but effective motion model and then robustly establish the correspondences via pyramid-based sparse optical flow tracking. In the second stage, we leverage the constraints of the motion smoothness and epipolar geometry to refine the correspondences. In particular, our method computes descriptors only for keyframes. We test FastORB-SLAM on TUM and ICL-NUIM RGB-D datasets and compare its accuracy and efficiency to nine existing RGB-D SLAM methods. Qualitative and quantitative results show that our method achieves state-of-the-art accuracy and is about twice as fast as the ORB-SLAM2. Copyright © 2020, The Authors. All rights reserved.

关键词： Optical flows

来源：评论

学校读者我要写书评

暂无评论

An Efficient and Privacy-preserving Energy Trading Scheme based on Blockchain

An Efficient and Privacy-preserving Energy Trading Scheme ba...

引用

IEEE Global Communications Conference

作者： Xin Lu Zhitao Guan Xiao Zhou Longfei Wu Xiaojiang Du Mohsen Guizani School of Control and Computer Engineering North China Electric Power University China Department of Mathematics and Computer Science Fayetteville State University Fayetteville USA Department of Computer and Information Science Temple University Philadelphia PA USA Department of Computer Science and Engineering Qatar University Doha Qatar

ISBN: (数字)9781728109626

ISBN: (纸本)9781728109633

Distributed transaction model has gradually replaced the traditional centralized transaction model and has become the leading direction of development in energy trading. As the underlying support, blockchain technology is attracting more and more attention due to its advantages, i.e., integrity and non-repudiation. However, most blockchain-based trading models face the problem of privacy protection. In this paper, to solve this problem, Ciphertext-Policy Attribute-Based Encryption (CP-ABE) is introduced as the core algorithm to reconstruct the transaction model. Specifically, we build a general model for distributed transaction called PP-BCTS (Privacy-Preserving Blockchain Trading Scheme). It can achieve fine-grained access control through transaction arbitration in ciphertext form. This design can maximize the protection of private information and can greatly improve the security and reliability of the transaction model. Additionally, a credibility-based equity proof consensus mechanism is proposed in PP-BCTS, which can greatly improve the operational efficiency. Security analysis and experimental evaluations are conducted to prove the validity and practicability of our proposed scheme.

关键词： Privacy Access control Encryption Data privacy

来源：评论

学校读者我要写书评

暂无评论

Kernelized support tensor train machines

arXiv

引用

arXiv 2020年

作者： Chen, Cong Batselier, Kim Yu, Wenjian Wong, Ngai Department of Electrical and Electronic Engineering University of Hong Kong Hong Kong Delft Center for Systems and Control Delft University of Technology Delft Netherlands BNRist Department of Computer Science and Technology Tsinghua University Beijing100084 China Department of Electrical and Electronic Engineering The University of Hong Kong Hong Kong

Tensor, a multi-dimensional data structure, has been exploited recently in the machine learning community. Traditional machine learning approaches are vector- or matrix-based, and cannot handle tensorial data directly. In this paper, we propose a tensor train (TT)-based kernel technique for the first time, and apply it to the conventional support vector machine (SVM) for image classification. Specifically, we propose a kernelized support tensor train machine that accepts tensorial input and preserves the intrinsic kernel property. The main contributions are threefold. First, we propose a TT-based feature mapping procedure that maintains the TT structure in the feature space. Second, we demonstrate two ways to construct the TT-based kernel function while considering consistency with the TT inner product and preservation of information. Third, we show that it is possible to apply different kernel functions on different data modes. In principle, our method tensorizes the standard SVM on its input structure and kernel mapping scheme. Extensive experiments are performed on real-world tensor data, which demonstrates the superiority of the proposed scheme under few-sample high-dimensional inputs. Copyright © 2020, The Authors. All rights reserved.

关键词： Tensors

来源：评论

学校读者我要写书评

暂无评论

Three-Phase D-STATCOM with Digital Current control Strategy in abc-Reference Frame

Three-Phase D-STATCOM with Digital Current Control Strategy ...

引用

International Conference on Computing, Mathematics and engineering Technologies (iCoMET)

作者： Tiago Davi Curi Busarello Kamran Zeb Muhammad Asim Sarwar Hee Je Kim Depart. Control Automation and Computation Engineering Federal University of Santa Catarina - UFSC Blumenau Brazil School of Electrical Engineering School of Electrical Engineering and Computer Science. Pusan National University National University of Sciences and Technology Busan South Korea Department Of Electrical Engineering Sukkur IBA University Pakistan School of Electrical Engineering Pusan National University Busan South Korea

ISBN: (数字)9781728149707

ISBN: (纸本)9781728149714

This paper proposes a Three-phase D-STATCOM with digital current control strategy in abc- reference frame. The proposal D-STATCOM does not use a PLL and the reactive power is transferred to the grid through controlling the D-STATCOM output current. The current controller has one zero and two poles. This type of controller is also known as Type-2 controller. The procedure to tune the controller is explained. The Conservative Power Theory (CPT) is used to compute the reactive power of the loads. A case study shows the behavior of the D-STACOM during initialization, during load transitions and during steady-state conditions. The results show the efficacy of the proposed D-STATCOM.

关键词： Automatic voltage control Reactive power Transfer functions Phase locked loops Mathematical model Filtering theory

来源：评论

学校读者我要写书评

暂无评论

Improved ECO Algorithm Based on Residual Neural Network

引用

Journal of Physics: Conference Series 2021年第1期1732卷

作者： Huifang Qi Changmeng Wang Bo Li School of Information Science and Engineering Yanshan University Qinhuangdao China School of Electrical Engineering Yanshan University Qinhuangdao China Key Laboratory of industrial computer control engineering in Hebei Province Yanshan University Qinhuangdao China

Video target tracking is one of hot fields of computer vision, and its application is also very extensive. However, due to the complexity and variability of tracking environment, which brings some challenges to the research of target tracking. ECO(Efficient Convolution Operators) Algorithm is proposed based on convolutional neural network in three aspects. Firstly, residual neural network ResNet50 is adopted instead of convolutional neural network to extract the appearance features of target, and deeper residual neural network is applied to obtain more abundant target semantic information, so as to improve the tracking effect of tracking ***, sample space classification strategy is improved. Different weights are assigned to shallow feature and deep feature, which make the deep feature play a more important role and improve the effect of target tracking. Finally, the method of scale estimation is improved so that better bounding boxes can be estimated with the scale changing. Experimental results show that the distance accuracy and success rate of the algorithm.

关键词：

来源：评论

学校读者我要写书评

暂无评论

control processes in mechatronic systems with friction: Research and modeling 10

Control processes in mechatronic systems with friction: Rese...

引用

10th International Scientific Conference BALTTRIB 2019

作者： Malafeev, S.I. Malafeev, S.S. Kopeykin, A.I. Department of Science Research Joint Power Co. Ltd. Moscow Russia Department of Computer Engineering and Control Systems Vladimir State University named after Alexander and Nikolay Stoletovs Vladimir Russia Vladimir Polytechnic College Vladimir Russia

Effect of friction on the motion control processes in mechatronic systems is considered. The analysis of modern friction modeling methods is carried out. Features of processes at low speeds: accuracy, oscillations and stability have been studied on base of macroscopic models of friction. Friction in the mechatronic system causes the formation of complex nonlinear speed feedback, which depends on many factors and has different signs at different speeds. Oscillations and a violation of the stability of the system are possible with positive feedback at low speed. The conditions of stable operation under frictional load for a DC motor are derived. Correction methods for mechatronic systems with friction are considered. Effective control in mechatronic systems achieve using the principle of subordinate coordinate control. The results of modeling systems with the main feedback on the angular speed and angle of rotation are presented. Copyright © 2019 The Authors.

关键词： Friction

来源：评论

学校读者我要写书评

暂无评论

Performance and Optimization of Reconfigurable Intelligent Surface Aided THz Communications

arXiv

引用

arXiv 2020年

作者： Du, Hongyang Zhang, Jiayi Guan, Ke Niyato, Dusit Jiao, Huiying Wang, Zhiqin Kürner, Thomas The School of Computer Science and Engineering The Energy Research Institute @ NTU Interdisciplinary Graduate Program Nanyang Technological University Singapore The School of Electronic and Information Engineering Beijing Jiaotong University Beijing100044 China The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China The School of Computer Science and Engineering Nanyang Technological University Singapore China Academy of Information and Communications Technology Beijing100191 China Technische Universität Braunschweig Brunswick38106 Germany

TeraHertz (THz) communications can satisfy the high data rate demand with massive bandwidth. However, severe path attenuation and hardware imperfection greatly alleviate its performance. Therefore, we utilize the reconfigurable intelligent surface (RIS) technology and investigate the RIS-aided THz communications. We first prove that the small-scale amplitude fading of THz signals can be accurately modeled by the fluctuating two-ray distribution based on two THz signal measurement experiments conducted in a variety of different scenarios. To optimize the phase-shifts at the RIS elements, we propose a novel swarm intelligence-based method that does not require full channel estimation. We then derive exact statistical characterizations of end-to-end signal-to-noise plus distortion ratio (SNDR) and signal-to-noise ratio (SNR). Moreover, we present asymptotic analysis to obtain more insights when the SNDR or the number of RIS's elements is high. Finally, we derive analytical expressions for the outage probability and ergodic capacity. The tight upper bounds of ergodic capacity for both ideal and non-ideal radio frequency chains are obtained. It is interesting to find that increasing the number of RIS's elements can significantly improve the THz communications system performance. For example, the ergodic capacity can increase up to 25% when the number of elements increases from 40 to 80, which incurs only insignificant costs to the system. © 2020, CC BY.

关键词： Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Steady state analysis of switched reluctance motor with modified geometry of the stator designed for an electric bike

Steady state analysis of switched reluctance motor with modi...

引用

2018 International Symposium on Electrical Machines, SME 2018

作者： Gabor, Rafal Kowol, Marcin Kolodziej, Janusz Mynarek, Piotr Opole University of Technology Faculty of Electrical Engineering Automatic Control and Computer Science Opole Poland

ISBN: (纸本)9781538652107

The paper contains a proposition of the application of a SRM motor with a modified stator geometry for an electric drive, in particular in an electric bicycle. The study involved a comparison of the cyclicity of the electromagnetic torque and self-inductance in the function of the rotor angle in 2D and 3D models based on the application of the finite element method. © 2018 IEEE.

关键词： Finite element method

来源：评论

学校读者我要写书评

暂无评论

Higher Harmonics and Power in Circuits with LED Light Sources

Higher Harmonics and Power in Circuits with LED Light Source...

引用

2018 Conference on Electrotechnology: Processes, Models, control and computer science, EPMCCS 2018

作者： Straczynski, Pawel Cislik, Miroslaw W. Department of Electrical Engineering Automatic Control and Computer Science Kielce University of Technology Kielce Poland

ISBN: (纸本)9781538682555

The paper deals with a power measurement methods and higher harmonics in circuit with LED light sources. The laws on the electric power quality in Poland has been presented. Current and voltage waveforms are analysed. The frequency spectrum of the current circuit is presented. The coefficients of power quality were determined and reference to the standard. The powers in the circuit with LED lamps were calculated and analysed. © 2018 IEEE.

关键词： Timing circuits

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：