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Gastric adenomyoma presenting as melena: A case report and literature review

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World Journal of Gastroenterology 2010年第15期16卷 1934-1936页

作者： Zhu, Hui-Neng Yu, jiang-Ping Luo, Juan jiang, you-hua Li, Jian-Qiang Sun, Wen-Yong Zhejiang Canc Hosp Dept Pathol Hangzhou 310022 Zhejiang Peoples R China Zhejiang Canc Hosp Dept Thoracicoabdominal Surg Hangzhou 310022 Zhejiang Peoples R China

Gastric adenomyoma (AM) is a rare benign tumor characterized by glandlike structures embedded within a smooth muscle stroma. We report a case of a 68yearold man with gastric AM admitted to our hospital for melana. Endoscopic examination revealed a gastric mass of about 4 cm in diameter, located in the antrum. Histologic examination of the excised specimen showed irregularly arranged glands and interlacing smooth muscle bundles surrounding the glandular elements. Although gastric AM is rare, it should be considered in differential diagnosis of extramucosal gastric tumor.

关键词： Adenomyoma Stomach Melana Histopathology Endoscopic examination

基于载波相移角度的级联型多电平变频器输出性能的研究

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中国电机工程学报 2007年第1期27卷 76-81页

作者：江友华曹以龙龚幼民上海大学机自学院上海市电站自动化技术重点实验室上海市闸北区200072 上海电力学院计算机系上海市杨浦区200090

载波相移PWM技术应用于级联型多电平变频器可以在较低的器件开关频率下实现较高开关频率的效果,从而提高其输出性能,但是不同的载波相移角度,输出性能并不完全一样,因此对载波相移PWM技术的相移角度同级联型多电平变频器输出性能进行了... 详细信息

载波相移PWM技术应用于级联型多电平变频器可以在较低的器件开关频率下实现较高开关频率的效果,从而提高其输出性能,但是不同的载波相移角度,输出性能并不完全一样,因此对载波相移PWM技术的相移角度同级联型多电平变频器输出性能进行了研究。该文通过数学推导和理论分析,得出载波移相180°/N和360°/N两种移相方式的输出性能同级联数目的奇偶数有关,当级联数目为奇数时,两者输出性能相差不大,但当级联数目为偶数时,两者的输出电压电平数,等效开关频率及谐波范围均不一样,载波移相180°/N方式比360°/N移相方式优,更适合工程应用。最后通过大量的仿真和实验验证了理论分析及相关结论的正确性。

关键词：电力电子谐波级联型多电平变频器载波相移角度

A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain

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Computers, Materials & Continua 2024年第6期79卷 4491-4512页

作者： Chunhui Li hua jiang School of Computer and Electronic Information Guangxi UniversityNanning530000China Cyber Security and Information Center Guangxi UniversityNanning530000China

In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of *** systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged *** existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited *** study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side *** this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and *** curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution *** encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective *** results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.

关键词： Cross-domain collaboration blockchain federated learning contribution value node management release slack resources

Finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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Science China(Information Sciences) 2024年第6期67卷 279-296页

作者： Yana YANG Huixin jiang Changchun hua Junpeng LI Institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are *** and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) ***, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ***, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

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混合有源滤波器多目标优化设计

控制理论与应用 2010年第7期27卷 916-922页

作者：江友华廖代发唐忠上海电力学院计算机与信息工程学院上海200090

针对混合有源滤波器参数设计和投资优化问题,综合考虑其初期投资成本、无功补偿、滤波效果等指标,提出一种基于遗传粒子群复合算法的混合有源滤波器多目标满意优化设计方法,建立起容量配置的多目标数学模型,并运用罚函数理论,将多目标... 详细信息

针对混合有源滤波器参数设计和投资优化问题,综合考虑其初期投资成本、无功补偿、滤波效果等指标,提出一种基于遗传粒子群复合算法的混合有源滤波器多目标满意优化设计方法,建立起容量配置的多目标数学模型,并运用罚函数理论,将多目标优化转化为单目标优化,使混合有源滤波器容量分配问题简单化,具有更大的适用性和灵活性.然后在电力系统计算机辅助设计/电磁暂态(PSCAD/EMTDC)环境下,对混合有源滤波器进行仿真分析,结果表明此优化设计的混合有源滤波器性价比得到提高.最后,通过实验对比,也验证了理论分析及相关结论的正确性.

关键词：混合有源滤波器改进型粒子群算法多目标优化

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城市电网谐波电流耦合机理分析与研究

控制理论与应用 2017年第2期34卷 233-242页

作者：江友华钱彦曹以龙上海电力学院电子与信息工程学院上海200090

本文针对多谐波源构成的多目标、非线性强耦合系统,从宏观层面上研究谐波源传导、输电线路传递、多谐波源叠加等耦合机理.为此,本文首先建立了多谐波源耦合模型;其次深入分析城市电网谐波耦合机理,多层次剖析谐波传导、谐波放大、谐波... 详细信息

本文针对多谐波源构成的多目标、非线性强耦合系统,从宏观层面上研究谐波源传导、输电线路传递、多谐波源叠加等耦合机理.为此,本文首先建立了多谐波源耦合模型;其次深入分析城市电网谐波耦合机理,多层次剖析谐波传导、谐波放大、谐波叠加等耦合因子及其特性.在此基础上,采用导纳矩阵对角化思路研究了多谐波源的解耦方式和解耦目标,为多谐波源的责任区分、谐波源治理提供清晰的思路.最后,通过应用案例及仿真验证了理论及算法的可行性.

关键词：多谐波源耦合机理谐波传导解耦

适用于用户侧的无触点分级有载电压调节器的设计

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电力系统保护与控制 2010年第3期38卷 104-109页

作者：江友华曹以龙唐忠上海电力学院计算机与信息工程学院上海200090

为了确保用户的供电电压质量,设计了一种适用于用户侧的无触点分级有载电压调节器,研究了其调压策略,重点对环流的产生机理进行了数学分析和推导,并计算出无暂态过程的晶闸管触发时刻,为相关产品设计提供了理论依据。通过实验及仿真可知... 详细信息

为了确保用户的供电电压质量,设计了一种适用于用户侧的无触点分级有载电压调节器,研究了其调压策略,重点对环流的产生机理进行了数学分析和推导,并计算出无暂态过程的晶闸管触发时刻,为相关产品设计提供了理论依据。通过实验及仿真可知,本装置具有调压精度高,响应快等特点,且由于有效抑制了环流,克服了分接头切换时刻的电流冲击。

关键词：无触点交流调压环流晶闸管

The dynamics beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 56-67页

作者： Zhen Liu Li-hua Wang Yong jiang Ya-Jun Tong hua-Chun Zhu Te Ji Min Chen Zheng jiang Xiang-Jun Wei Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China

The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved *** combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme ***,ED-XAS and SR-IR can be used independently in the two branches of the *** ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample *** exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy *** focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 *** one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be *** distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.

关键词： ED-XAS SR-IR Time-resolved D-line SSRF

Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research International 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu Zhou-hua jiang hua-bing Li Rui Zhang Hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time