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Protection and Control of Modern Power Systems 2023年第1期8卷 97-111页

作者： Yingyu Liang Yi Ren Jinhua yu Wenting zha School of Mechanical Electronic and Information Engineering China University of Mining and Technology(Beijing) Beijing 100083China

In the presence of an MMC-HVDC system,current differential protection(CDP)has the risk of failure in operation under an internal *** addition,CDP may also incur security issues in the presence of current transformer(CT)saturation and *** this paper,a current trajectory image-based protection algorithm is proposed for AC lines connected to MMC-HVDC stations using a convolution neural network improved by a channel attention mechanism(CA-CNN).Taking the dual differential currents as two-dimensional coordinates of the moving point,the moving-point trajectories formed by differential currents have significant differences under internal and external ***,internal faults can be identified using image recognition based on *** is improved by a channel attention mechanism,data augmentation,and adaptive learning *** comparison with other machine learning algorithms,the feature extraction ability and accuracy of CA-CNN are greatly *** fault conditions like different net-work structures,operation modes,fault resistances,outliers,and current transformer saturation,are fully considered to verify the superiority of the proposed protection *** results confirm that the proposed current trajectory image-based protection algorithm has strong learning and generalizability,and can identify internal faults reliably.

关键词： Channel attention mechanism Convolutional neural network(CNN) Differential current Current trajectory image Modular multilevel converter-based high voltage direct current(MMC-HVDC)

An Algorithm for Determination of Projectile Attitude Angles in Projectile Trajectory Prediction

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第2期35卷 361-370页

作者： zha.Qicheng Rui Xiaoting yu Hailong Zhou Qinbo Institute of Launch Dynamics School of Energy and Power EngineeringNanjing University of Science and Technology

A fast and accurate algorithm is established in this paper to increase the precision of ballistic trajectory *** algorithm is based on the six-degree-of-freedom(6 DOF)trajectory equations,to estimate the projectile attitude angles in every measuring ***,the algorithm utilizes the Davidon-Fletcher-Powell(DFP)method to solve nonlinear equations and Doppler radar trajectory test information containing only position coordinates of the projectile to reconstruct the angular ***″position coordinates by the test″and″angular displacements by reconstruction″at the end phase of the radar measurement are used as an initial value for the trajectory computation to extrapolate the trajectory impact *** numerical simulations validate the proposed method and demonstrate that the estimated impact point agrees very well with the real ***,other artillery trajectory can be predicted by the algorithm,and other trajectory models,such as 4 DOF and 5 DOF models,can also be incorporated into the proposed algorithm.

关键词： ballistic trajectory impact point prediction Davidon-Fletcher-Powell method six-degree-of-freedom trajectory model Doppler radar data

Ballistic Trajectory Extrapolation and Correction of Firing Precision for Multiple Launch Rocket System

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第2期36卷 232-241页

作者： zha.Qicheng RUI Xiaoting WANG Guoping yu Hailong Institute of Launch Dynamics School of Energy and Power EngineeringNanjing University of Science and Technology

The research on multiple launch rocket system(MLRS)is now even more demanding in terms of reducing the time for dynamic calculations and improving the firing accuracy,keeping the cost as low as *** study employs multibody system transfer matrix method(MSTMM),to model *** use of this method provides effective and fast calculations of dynamic characteristics,initial disturbance and firing ***,a new method of rapid extrapolation of ballistic trajectory of MLRS is proposed by using the position information of radar *** extrapolation point is then simulated and compared with the actual results,which demonstrates a good *** closed?loop fire correction method is used to improve the firing accuracy of MLRS at low cost.

关键词： multi-body system transfer matrix method(MSTMM) multiple launch rocket system(MLRS) dynamic modeling ballistic trajectory extrapolation fire correction method

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巴西龟代谢性骨病CT诊断病例报告

动物医学进展 2025年第1期46卷 141-144页

作者：孙嘉徐甘靖宇江蓝刘波俞峰中国农业大学北京100193

代谢性骨病(MBD)是一种因钙缺乏或维生素D 3摄入不足引起的骨骼代谢障碍疾病,其临床表现为骨折、脊椎异常、难产、脱垂等症状。计算机断层扫描(CT)在兽医临床中应用的逐渐增加为龟、鳖类MBD提供了新的诊断方式。该病例中红耳巴西龟血检... 详细信息

代谢性骨病(MBD)是一种因钙缺乏或维生素D 3摄入不足引起的骨骼代谢障碍疾病,其临床表现为骨折、脊椎异常、难产、脱垂等症状。计算机断层扫描(CT)在兽医临床中应用的逐渐增加为龟、鳖类MBD提供了新的诊断方式。该病例中红耳巴西龟血检结果提示其肾脏、肝脏功能损害,钙磷代谢异常。CT扫查提示患龟全身组织大面积矿化、背甲凹陷,定量测量患龟背椎骨、神经骨和胸膜骨3处的骨骼密度远低于正常龟,诊断患龟有严重的MBD。治疗方案为对症治疗、改善饲养管理条件,同时对该龟补充维生素D 3。该病例报告系统陈述了龟鳖MBD的诊疗流程,同时表明了CT扫查可为龟鳖MBD精确诊断、治疗和预后提供新的参考。

关键词：龟代谢性骨病计算机断层扫描骨密度

A Hybrid MCDM Approach Based on ANP and TOPSIS for Facility Layout Selection

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第6期35卷 1027-1037页

作者： zha.Shanshan Guo yu Huang Shaohua Tang Pengzhou College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Facility layout selection is a multi-criteria decision making (MCDM) problem,since it has a strategic impact on the efficiency of manufacturing *** view of the interdependency among selection criteria,analytic network process (ANP) is proposed to analyze the structure of the facility layout selection problem and determine the weights for each criterion.A network structure is constructed that shows all elements and clusters and their *** priorities are also calculated which help decision maker evaluate the relative importance among criterion in the alternative selection ***,a hybrid MCDM approach that employs ANP and technique for order preference by similarity to an ideal solution (TOPSIS)method to rank the optimal facility layout ***,an application of a new aeronautic component assembly workshop facility layout selection is *** further illustrate the advantage of the proposed approach,the difference between ANP-TOPSIS and AHP-TOPSIS methods are compared and *** have demonstrated the effectiveness and feasibility of the proposed method.

关键词： facility layout selection multi-criteria decision making(MCDM) analytic network process AHP TOPSIS

Optimized damping for LCL filters in three-phase voltage source inverters coupled by power grid

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Journal of Modern Power Systems and Clean Energy 2017年第4期5卷 642-651页

作者： Meng HUANG Jianjun SUN yu PENG Xiaoming zha Wuhan University WuhanChina Wuhan Electric Power Technical College WuhanChina

The application of LCL filters has become popular for inverters connected to the power grid due to their advantages in harmonic current reductions. However,the power grid in a distribution system is non-ideal, presenting itself as a voltage source with significant impedance. This means that an inverter using an LCL filter may interact with other grid-connected inverters via the nonideal grid. In this paper, damping optimization of LCLfilters to reduce this interaction is studied for a three-phase voltage source inverter(VSI). Simulation results show that resonant oscillation occurs in a distributed power grid, even if the VSI with an LCL filter is well designed for standalone applications. A small-signal analysis is performed to predict this stability problem and to locate the boundary of the instability using an impedance approach. Based on these analytical results, optimized damping of the LCLfilter can be designed. The oscillation phenomena and optimized damping design are verified by simulations and experimental measurements.

关键词： LCL filter Three-phase voltage source inverter Non-ideal power grid Optimized design Interacting converters

Efficient photocatalytic reduction of chromium(Ⅵ) using photoreduced graphene oxide as photocatalyst under visible light irradiation

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Journal of Materials Science & Technology 2021年第32期91卷 17-27页

作者： Mei yu jing Shang yu Kuang Department of Environment and Health State Key Joint Laboratory of Environmental Simulation and Pollution ControlCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Graphene oxide(GO),a new and promising material,has been widely used as a co-catalyst in photocatalytic reactions;however,its capacity as a sole photocatalyst has rarely been *** this study,ultraviolet(UV) light irradiation was used as a modification method to obtain reduced GO(rGO) *** samples were used as photocatalysts to examine their visible light photocatalytic activity toward hexavalent chromium(Cr(Ⅵ)) *** force microscopy(AFM),X-ray diffraction(XRD),UV-vis spectrophotometry,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and electron spin resonance(ESR) spectroscopy were applied to interpret the surface and structure changes with UV *** oxygen-containing functional groups(OFGs) on the GO surface were reduced to defective carbons andπ-conjugated C=C(sp^(2) domains) under UV light;this led to a decrease in the interlayer distance between GO sheets,GO fragmentation,and increased disorder on the GO *** restoration of sp^(2) domains led to a narrower band gap of GO,which favored the rGO excitation by visible light to generate electron-hole *** rGO pre-irradiated with UV for 1 h(rGO-1),possessing the highest defect density and electron generation efficiency,exhibited the best Cr(Ⅵ) reduction efficiency,which was about three times that of the GO sample;moreover,it outperformed most of the reported GO-based *** addition,low pH and the addition of citric acid as a hole scavenger could further improve the photocatalytic *** study proves that GO or rGO can be used as a sole photocatalyst under visible light to remove environmental pollutants such as heavy-metal ions,and it paves the way for the development of this kind of material and its UV-irradiation modification for further applications.

关键词： Graphene oxide Chromium(Ⅵ) Defect density UV-irradiation modification Photocatalytic reduction

Adaptive dynamic surface control of NSVs with input saturation using a disturbance observer

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Chinese Journal of Aeronautics 2015年第3期28卷 853-864页

作者： Chen Mou yu jing College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Abstract An adaptive dynamic surface control （DSC） scheme is proposed for the multiinput and multioutput （MIMO） attitude motion of nearspace vehicles （NSVs） in the presence of external dis turbance, system uncertainty and input saturation. The external disturbance and the system uncer tainty are efficiently tackled using a Nussbaum disturbance observer （NDO）, and the adaptive controller is constructed by combining the dynamic surface control technique to handle the problem of ＂explosion of complexity＂ inherent in the conventional backstepping methodl For handling the input saturation, an auxiliary system is designed with the same order as that of the studied MIMO attitude system. Using the error between the saturation input and the desired control input as the input of the designed auxiliary system, a series of signals are generated to compensate for the effect of the saturation in the dynamic surface control design. It is proved that the developed control scheme can guarantee that all signals of the closedloop control system are semiglobally uniformly bounded. Finally, simulation results illustrate that the proposed control scheme can achieve satis factory tracking performance under the composite effects of the input saturation and the external disturbance.

关键词： Auxiliary system Disturbance observer Dynamic surface controlInput saturation Near-space vehicle

定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

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Mechanism of action of Linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： Huan Pei Ren-Lin Li Xin-Ran Song Qian-Qian Wan yu-Ming Wang Han-Zhou Li Wei-Quan Xu Jia-Bao Liao Wei-Bo Wen jing Miao Huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle