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MDCFS: few-shot object detection with multilevel decoupled classifiers

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Optoelectronics Letters 2025年

作者： LI Chuanhui zhou Mian feng Zhikun SUI Zezhou GAO Zhan School of Computer Science and Engineering， Tianjin University of Technology

Few-shot object detection poses unique challenges as it requires effectively learning novel classes with limited labeled data. Current approaches often suffer from biases towards base classes during fine-tuning， leading to suboptimal performance on detecting novel classes. Additionally， in complex scenes， the confusion between foreground and background objects further affects the accuracy and robustness of the model. To address these issues， we propose the Multilevel Decoupling Classification Few-Shot Algorithm (MDCFS). we decouple the standard classifier into a parallel foreground classifier and a background classifier in the Few-Shot Object Detection (FSOD) setting. This decoupling enables the independent separation of positive samples from noisy negative samples， alleviating the foreground-background confusion problem commonly encountered in few-shot detectors. For Generalized Few-Shot Object Detection (G-FSOD)， where the few-shot dataset contains base classes， we further decouple the foreground classification head into a base class classification head and a novel class classification head. To ensure balance， we assign more weight to the novel class classification head， effectively addressing the bias towards base classes. Furthermore， we optimize the initial weights of the few-shot fine-tuning stage， significantly reducing training time and mitigating catastrophic forgetting in G-FSOD. Additionally， we incorporate metric learning into our model with minimal cost. Experimental results demonstrate the effectiveness of our approach. Compared to state-of-the-art few-shot object detection methods based on fine-tuning， MDCFS achieves performance improvements of up to 6.3% on the PASCAL VOC dataset and 1.5% on the COCO dataset.

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基于混合有限元法的钢箱拱相关稳定分析

铁道科学与工程学报 2007年第6期4卷 7-11页

作者：何旭辉封周权陈政清余志武中南大学土木建筑学院湖南长沙410075 湖南大学风工程试验研究中心湖南长沙410082

针对薄壁结构提出了一种混合有限元方法,对结构关心的部位采用板壳单元模拟,其他部位采用杆系单元模拟,根据平截面假定推导了2种单元在交界面处的约束方程,由此建立整体混合有限元模型。通过算例验证了该方法的可靠性,可以计算薄壁结构... 详细信息

针对薄壁结构提出了一种混合有限元方法,对结构关心的部位采用板壳单元模拟,其他部位采用杆系单元模拟,根据平截面假定推导了2种单元在交界面处的约束方程,由此建立整体混合有限元模型。通过算例验证了该方法的可靠性,可以计算薄壁结构的整体稳定、局部稳定和整体局部相关稳定。用该方法对某座刚构-单肋钢箱系杆拱组合桥梁进行特征值和弹塑性稳定分析,得到了相应的稳定系数和失稳模态。实例显示,该方法既可以弥补梁单元模型无法计算构件局部屈曲的不足,又可克服局部板壳模型无法准确模拟其整体边界条件及工作环境的缺点,还可以避免全结构板壳模型产生过多单元数量和庞大结构刚度矩阵的弊端,计算可靠性和计算效率大大提高。

关键词：混合有限元约束方程钢箱拱相关稳定

1.56 kV/30 A vertical β-Ga2O3 Schottky barrier diodes with composite edge terminations

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Science China(Information Sciences) 2025年

作者： Yitao feng Hong zhou Sami ALGHAMDI Hao FANG Xiaorong ZHANG Yanbo CHEN Guotao TIAN Saud WASLY Yue HAO Jincheng ZHANG Key Lab of Wide Band Gap Semiconductor Materials and Devices School of MicroelectronicsXidian University Center of Excellence in Intelligent Engineering Systems (CEIES) King Abdulaziz University China Resources Microelectronics Limited(Wuxi)

In recent years, large-area wide-bandgap (WBG) semiconductor materials have achieved numerous notable breakthroughs [1, 2]. The ultra-WBG semiconductor β-Ga2O3,with its excellent material properties, is ideally suited for the fabrication of power devices. Moreover, it offers easily obtainable large-area substrates, with reported sizes up to 6 inches, produced through melt-grown crystal growth methods. These characteristics make β-Ga2O3 highly attractive for future low-cost commercialization. Despite these advances, most research has focused on low-current and small-size diodes, with few studies addressing high-current and large-size diodes.

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FAS在缺血性心力衰竭中的作用

中国分子心脏病学杂志 2007年第4期7卷 237-240页

作者：冯全洲王士雯赵玉生解放军总医院老年心血管病研究所北京100853

心肌细胞的凋亡和代偿性肥大是缺血性心力衰竭发展过程中的两个重要方面。过去曾认为Fas与缺血后心肌细胞的凋亡有关,但近来研究发现两者并没有直接关系,并认为Fas与心肌细胞肥大有关,本文就这方面的研究进行综述。

关键词： Fas 缺血心力衰竭细胞凋亡

Unraveling the mechanism of action of Shangxia Liangji formula for treating insomnia:a metabolomics and network pharmacology approach

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Traditional Medicine Research 2025年第2期10卷 16-29页

作者： Xia-Jie quan Hao Liang Yong-Hong Tang Li Jiang Xiong-Ying Ji feng-Ying Zhang Ping Zhang Bo Ouyang Department of Information The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Neurology The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Gastroscopy The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Traditional Chinese Medicine The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China

Background:Insomnia is a prevalent clinical condition and Shangxia Liangji formula(SXLJF)is a well-established method of ***,the specific mechanism of action of SXLJF remains ***:The mouse model of insomnia was established by intraperitoneal injection of ***-two mice were randomly divided into a negative control group,model group,SXLJF group(18.72 g/kg/day),and positive control group(diazepam,2 mg/kg)and treated with the corresponding drugs for 7 consecutive *** open field test and pentobarbital-induced sleeping test were ***-MS-based untargeted metabolomics and network pharmacology were applied to explore the potential targets of SXLJF for treating ***,key targets were validated using ***:Behavioral tests demonstrated that SXLJF reduced the total distance,average velocity,central distance,and sleep latency,and prolonged sleep *** and network pharmacology revealed potential targets,signaling pathways,metabolic pathways,and metabolites associated with the anti-insomnia effects of ***,tyrosine hydroxylase(TH)and tyrosine metabolism emerged as crucial metabolic pathways and targets,***-qPCR results supported the role of TH in the mechanism of SXLJF in treating ***:In conclusion,TH and tyrosine metabolism may represent significant targets and pathways for SXLJF in treating insomnia.

关键词： Shangxia Liangji formula insomnia metabolomics network pharmacology tyrosine hydroxylase tyrosine metabolism

Three-stage Defensive Framework for Distributed Microgrid Control Against Cyberattacks

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1669-1678页

作者： Xuanyi Xiao quan zhou feng Wang Wen Huang College of Electrical and Information Engineering Hunan UniversityChangsha 410082China IEEE

With the wide integration of various distributed communication and control techniques,the cyber-physical microgrids face critical challenges raised by the emerging *** paper proposes a three-stage defensive framework for distributed microgrids against denial of service(DoS)and false data injection(FDI)attacks,including resilient control,communication network reconfiguration,and switching of local *** resilient control in the first stage is capable of tackling simultaneous DoS and FDI attacks when the connectivity of communication network could be maintained under *** communication network reconfiguration method in the second stage and the subsequent switching of local control in the third stage based on the software-defined network(SDN)layer aim to cope with the network partitions caused by *** proposed defensive framework could effectively mitigate the impacts of a wide range of simultaneous DoS and FDI attacks in microgrids without requiring the specific assumptions of attacks and prompt detections,which would not incorporate additional cyberattack *** case studies using a 13-bus microgrid system are conducted to validate the effectiveness of the proposed three-stage defensive framework against the simultaneous DoS and FDI attacks.

关键词： Microgrid cyber-physical systems cyberattack distributed control defensive framework

Regular Maps of Graphs of Order 4p

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Acta Mathematica Sinica,English Series 2012年第5期28卷 989-1012页

作者： Jin Xin zhou Yan quan feng Department of Mathematics Beijing Jiaotong University

A 2-cell embedding f ： X → S of a graph X into a closed orientable surface S can be described combinatorially by a pair M = （X; p） called a map, where p is a product of disjoint cycle permutations each of which is the permutation of the arc set of X initiated at the same vertex following the orientation of S. It is well known that the automorphism group of M acts semi-regularly on the arc set of X and if the action is regular, then the map M and the embedding f are called regular. Let p and q be primes. Duet al. [J. Algebraic Combin., 19, 123 141 （2004）] classified the regular maps of graphs of order pq. In this paper all pairwise non-isomorphic regular maps of graphs of order 4p are constructed explicitly and the genera of such regular maps are computed. As a result, there are twelve sporadic and six infinite families of regular maps of graphs of order 4p; two of the infinite families are regular maps with the complete bipartite graphs K2p,2p as underlying graphs and the other four infinite families are regular balanced Cayley maps on the groups Z4p, Z22 × Zp and D4p.

关键词： Regular map Cayley map algebraic map 2-cell embedding

Modelling and numerical simulation of isothermal oxidation of an individual magnetite pellet based on computational fluid dynamics

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Journal of Iron and Steel Research International 2021年第7期28卷 799-808页

作者： zhou Pu feng zhou Yue Sun Ming Zhang Bo-quan Li Department of Instrumentation Science and Technology Jiangsu UniversityZhenjiang 212013JiangsuChina

A mathematical model based on the computational fluid dynamics method,heat and mass transfer in porous media and the unreacted shrinking core model for the oxidation reaction of an individual magnetite pellet during preheating was *** commercial software COMSOL Multiphysics was used to simulate the change in the oxidation degree of the pellet at different temperatures and oxygen concentrations,and the simulated results were compared with the exper-imental *** model considered the influence of the exothermic heat of the reaction,and the enthalpy change was added to calculate the heat released by the *** results show that the oxidation rate on the surface of the pellet is much faster than that of the inside of the *** and oxygen concentration have great influence on the pellet oxidation ***,the exothermic calculation results show that there is a non-isothermal phenomenon inside the pellet,which leads to an increase in temperature inside the single *** the preheating condition of 873-1273 K(20%oxygen content),the heat released by the pellet oxidation reaction in a chain grate is 7.8×10^(6)-10.8×10^(6) kJ/h,which is very large and needs to be considered in the magnetite pellet oxidation modelling.

关键词： Magnetite pellet Oxidation Numerical simulation Unreacted shrinking core model Computational fluid dynamics

Evaluation of the therapeutic significance of Glehniae Radix polysaccharides on the ulcerative colitis through DSS-induced rat model

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Food Science and Human Wellness 2025年

作者： Jie Liu Xufang Geng Yuxin Yang Jiao Xu Haoran feng Tianshuo Zhang Guangzhao zhou Man Wang Changshun Wang Dongsheng Jia Yuting Chen Bin Cong Ding Zhao The Postdoctoral Mobile Station of Basic Medicine， Hebei Medical University The Department of Pharmacognosy， School of Pharmacy， Hebei Medical University Hebei Key Laboratory of Forensic Medicine， College of Forensic Medicine， Hebei Medical University

Glehniae Radix has a wide range of pharmaceutical applications， and research on its main components has mainly focused on coumarins， alkaloids， lignans， and flavonoids， while neglecting the research on polysaccharides. Literature reports and our previous studies have shown that polysaccharides have certain therapeutic significance in immune regulation， antioxidant， anti-inflammatory and other aspects. Herein， the rat model of ulcerative colitis (UC) was established to evaluate the anti-inflammatory efficacy of the prepared Glehniae Radix polysaccharide (GLP) from the perspectives of inflammatory factors， intestinal tissue morphology， and microflora changes. The polysaccharides are mainly composed of galacturonic acid， rhamnose， glucose， galactose， and arabinose in molar ratios of 1.4:9.2:33.3:2.5:2.9， and GLP could downregulate the expression pro-inflammatory factors (interleukin-6， tumor necrosis factor-α， and interferon-γ) and significantly upregulate the expression of anti-inflammatory factor (interleukin-10). In addition， Glehniae Radix aqueous extract (GLA)， GLP with low dosage (GLPL) and GLP with high dosage (GLPH) could increase the number of goblet cells， enhance the integrity of crypt structure， and reverse the status of inflammatory infiltrating cells. Moreover， GLA and GLPH could upregulate Lactobacillus and Lachnoclostridium in UC rats， and appropriately downregulate Lachnospiraceae＿NK4A136＿group， thereby optimizing the proportion of bacterial flora and improving the intestinal microbial environment. Our findings not only be valuable as theoretical materials for the further clinical applications of GLP， but the identified biomarkers and metabolic pathways also provide new clues for the diagnosis of UC.

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