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Journal of Central South University 2014年第4期21卷 1396-1401页

作者：王琪洁杜亚男刘建 School of Geosciences and Info-Physics Central South University

The general regression neural network(GRNN) model was proposed to model and predict the length of day(LOD) change, which has very complicated time-varying characteristics. Meanwhile, considering that the axial atmospheric angular momentum(AAM) function is tightly correlated with the LOD changes, it was introduced into the GRNN prediction model to further improve the accuracy of prediction. Experiments with the observational data of LOD changes show that the prediction accuracy of the GRNN model is 6.1% higher than that of BP network, and after introducing AAM function, the improvement of prediction accuracy further increases to 14.7%. The results show that the GRNN with AAM function is an effective prediction method for LOD changes.

关键词：神经网络模型回归神经网络预测模型大气角动量 GRNN 广义预测精度 LOD

Design and Application of an S-band Fast Radio Bursts Search Pipeline for the nanshan 26 m Radio Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 114-120页

作者： yan-Ling Liu Mao-Zheng Chen Jian Li Jian-Ping Yuan Rai Yuen Zhi-Yong Liu Hao yan Wen-Long du nan-nan Zhai Xinjiang Astronomical Observatory Chinese Academy of Sciences Xinjiang Key Laboratory of Microwave Technology University of Chinese Academy of Sciences

Fast radio bursts(FRBs) are among the most studied radio transients in astrophysics, but their origin and radiation mechanism are still unknown. It is a challenge to search for FRB events in a huge amount of observational data with high speed and high accuracy. With the rapid advancement of the FRB research process, FRB searching has changed from archive data mining to either long-term monitoring of the repeating FRBs or all-sky surveys with specialized equipments. Therefore, establishing a highly efficient and high quality FRB search pipeline is the primary task in FRB research. Deep learning techniques provide new ideas for FRB search processing. We have detected radio bursts from FRB 20201124A in the L-band observational data of the nanshan 26 m radio telescope(NSRT-26m) using the constructed deep learning based search pipeline named dispersed dynamic spectra search(DDSS). Afterwards, we further retrained the deep learning model and applied the DDSS framework to S-band observations. In this paper, we present the FRB observation system and search pipeline using the S-band *** carried out search experiments, and successfully detected the radio bursts from the magnetar SGR J1935+2145and FRB 20220912A. The experimental results show that the search pipeline can complete the search efficiently and output the search results with high accuracy.

关键词： methods: data analysis methods: observational radio continuum: general

Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification

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Communications in Theoretical Physics 2024年第7期76卷 136-146页

作者： Da-cheng Ma Ling-yi Cui Chu-xiao Sun Xiao-dan Chi Zheng-nan XianYu An du College of Science Northeastern University Department of Basic Science Dalian Naval Academy Department of Physics College of Sciences Shenyang University of Chemical Technology National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of Education

Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature, although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin–Wagner theorem. By use of the spin Green's function method, we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature, whether the decorated edge spins of the system link together or separate from each other. When the width of the nanoribbon achieves infinite limit, the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the nanoribbon. The results reveal that the magnetism of a low-dimensional spin system is different from that of a three-dimensional spin system. When the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally, various useful long-range magnetic orders of the system can be obtained. This work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

关键词： Heisenberg model long-range magnetic order magnetic anisotropy nanoribbon transition temperature

Mechanism of high-energy pulsed current-assisted rolling of 08AL carbon steel ultra-thin strip

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Journal of Iron and Steel Research(International) 2024年第2期31卷 416-427页

作者： Zhong-kai Ren ya-nan Xu Jia-zhao Chen He Li Rui-lin Yuan Zhen-hua Wang Tao Wang Xiao Liu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment(Ministry of Education) Taiyuan University of TechnologyTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710016ShaanxiChina

To improve the plastic deformation performance of a 08AL carbon steel ultra-thin strip,a pulsed electric field was integrated into the plastic processing of the ultra-thin strip,and the effects of high-energy current on its deformation ability were ***-assisted tensile tests were employed,and the results clarified that the pulsed current could reduce the activation energy of faults and promoted dislocation slip within grains and at grain boundaries,leading to a decrease in the deformation resistance of the metal and an increase in its plastic *** the current density of 2.0 A/mm2,the yield strength,tensile strength,and elongation of the rolled sample reached 425 MPa,467 MPa,and 12.5%,*** the rolling process,it was found that the pulsed current promoted the dynamic recrystallization of the ultra-thin strip,reduced its dislocation density and deformation resistance,and promoted the coordinated deformation of the metal.

关键词： 08AL ultra-thin strip High-energy pulsed current Mechanical property Dislocation density Dynamic recrystallization

The RFI Fast Mitigation Algorithm Based on Block LMS Filter

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Research in Astronomy and Astrophysics 2024年第1期24卷 265-272页

作者： Han Wu Hai-Long Zhang ya-Zhou Zhang Jie Wang Xu du Ting Zhang Xin-Chen Ye Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China

The radio telescope possesses high sensitivity and strong signal collection *** receiving celestial radiation signals,it also captures Radio Frequency Interferences(RFIs)introduced by human ***,as signals originating from sources other than the astronomical targets,significantly impacts the quality of astronomical *** paper presents an RFI fast mitigation algorithm based on block Least Mean Square(LMS)*** enhances the traditional adaptive LMS filter by grouping L adjacent time-sampled points into one block and applying the same filter coefficients for filtering within each *** transformation reduces multiplication calculations and enhances algorithm efficiency by leveraging the time-domain convolution *** algorithm is tested using baseband data from the Parkes 64 m radio telescope's pulsar observations and simulated *** results confirm the algorithm's effectiveness,as the pulsar profile after RFI mitigation closely matches the original pulsar profile.

关键词： methods:data analysis techniques:interferometric (stars:)pulsars:individual(J0437-4715)

一种冲击噪声下相干分布源多峰DOA估计方法

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电子学报 2023年第9期51卷 2330-2340页

作者：高洪元刘亚鹏杜亚男程建华孙贺麟哈尔滨工程大学信息与通信工程学院黑龙江哈尔滨150001 哈尔滨工程大学智能科学与工程学院黑龙江哈尔滨150001

针对现有相干分布源波达方向(Direction Of Arrival,DOA)估计方法计算量大、抗冲击噪声能力弱和不能有效去相干等难题,本文提出了一种冲击噪声下相干分布源多峰DOA估计方法,并推导了冲击噪声下相干分布源DOA估计的克拉美罗界.为了实现... 详细信息

针对现有相干分布源波达方向(Direction Of Arrival,DOA)估计方法计算量大、抗冲击噪声能力弱和不能有效去相干等难题,本文提出了一种冲击噪声下相干分布源多峰DOA估计方法,并推导了冲击噪声下相干分布源DOA估计的克拉美罗界.为了实现冲击噪声下相干分布源DOA估计,采用加权范数协方差抑制冲击噪声,进而首次推导出多峰加权信号子空间拟合方程,并设计了一种多峰量子秃鹰算法快速无量化误差求解.仿真结果表明,所提方法在冲击噪声下能够以较小的快拍数实现相干分布源DOA估计,且无需额外的解相干操作即可有效去相干.与一些已有的高精度DOA估计方法相比,所提方法仿真时间明显缩短,且具有更高的估计精度和估计成功概率,突破了已有相干分布源DOA估计方法的应用局限,可推广应用于其他复杂的DOA估计问题中.

关键词：相干分布源 DOA估计冲击噪声多峰加权信号子空间拟合多峰量子秃鹰算法克拉美罗界

Effective assignment of positional isomers in dimeric shikonin and its analogs by ^(1)H NMR spectroscopy

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Chinese Chemical Letters 2024年第5期35卷 223-226页

作者： Ling-Hao Zhao Hai-Wei yan Jian-Shuang Jiang Xu Zhang Xiang Yuan ya-nan yang Pei-Cheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and ***,the ^(1)H(proton)nuclear magnetic resonance(NMR)pattern of phenolic hydroxyl protons was developed as a“diagnosis signal”to ascertain the relative location of each side chain in DMSO-d_(6) at sample concentrations of 0.022-0.034 mol/*** chemical shift differences of 0.6ppm between OH-5' and OH-1 and between OH-8'and OH-4 are assigned to Type A and Type B,*** reported ambiguous structures were corrected by this ***,the steric structures of isolated compounds were elucidated by quantum chemical calculations of electronic circular dichroism(ECD)spectra.

关键词： Arnebia euchroma Dimeric hydroxyl naphthoquinones Positional isomers ^(1)H NMR spectroscopy Chemical shift difference

Efficacy of ginseng-based Renshenguben oral solution for cancer-related fatigue among patients with advanced-stage hepatocellular carcinoma:A prospective multicenter cohort study

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 249-256页

作者： Ming-Da Wang Chen Yuan Ke-Chun Wang nan-ya Wang Ying-Jian Liang Hong Zhu Xiang-Min Tong Tian yang Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterFirst Hospital of Jilin UniversityChangchun 130021China Department of Hepatobiliary Surgery Eastern Hepatobiliary Surgery HospitalSecond Military Medical University(Naval Medical University)Shanghai 200438China Department of Clinical Laboratory Laboratory Medicine CenterZhejiang Provincial People’s HospitalHangzhou Medical CollegeHangzhou 310000China Department of Hepatobiliary Surgery First Affiliated Hospital of Harbin Medical UniversityHarbin 150007China Department of Medical Oncology First Affiliated Hospital of Soochow UniversitySuzhou 215006China fDepartment of Central Laboratory Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhou 310006China

Background:Cancer-related fatigue(CRF)is a common and debilitating symptom experienced by patients with advanced-stage cancer,especially those undergoing antitumor *** study aimed to evaluate the efficacy and safety of Renshenguben(RSGB)oral solution,a ginseng-based traditional Chinese medicine,in alleviating CRF in patients with advanced hepatocellular carcinoma(HCC)receiving antitumor ***:In this prospective,open-label,controlled,multicenter study,patients with advanced HCC at BCLC stage C and a brief fatigue inventory(BFI)score of≥4 were *** were assigned to the RSGB group(RSGB,10 mL twice daily)or the control group(with supportive care).Primary and secondary endpoints were the change in multidimensional fatigue inventory(MFI)score,and BFI and functional assessment of cancer therapy-hepatobiliary(FACT-Hep)scores at weeks 4 and 8 after *** events(AEs)and toxicities were ***:A total of 409 participants were enrolled,with 206 assigned to the RSGB *** week 4,there was a trend towards improvement,but the differences were not statistically *** week 8,the RSGB group exhibited a significantly lower MFI score(Pduced CRF in patients with advanced HCC undergoing antitumor therapy over an eight-week period,with no discernible *** findings support the potential of RSGB oral solution as an adjunctive treatment for managing CRF in this patient population.

关键词： Cancer-related fatigue Hepatocellular carcinoma Renshenguben oral solution Efficacy Safety Ginseng

Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： Xue-Ping du Guang-Lei Yu ya-Cheng Xu Zhi-Jie Chen Nai-Liang Li Huan-Guang Wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi'an Jiaotong UniversityXi'an710049ShaanxiChina Xi'an Aerospace Propulsion Test Technology Institute Xi'an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure *** results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer

Naringin ameliorates H_(2)O_(2)-induced oxidative damage in cells and prolongs the lifespan of female Drosophila melanogaster via the insulin signaling pathway

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Food Science and Human Wellness 2024年第3期13卷 1231-1245页

作者： Xiaomei du Kexin Wang Xiaoyan Sang Xiangxing Meng Jiao Xie Tianxin Wang Xiaozhi Liu Qun Huang nan Zhang Hao Wang State Key Laboratory of Food Nutrition and Safety Tianjin University of Science and TechnologyTianjin 300457China The key Laboratory of Environmental Pollution Monitoring and Disease Control Ministry of EducationGuizhou Medical UniversityGuizhou 550025China Department of neurosurgery the Fifth Central Hospital of TianjinTianjin 300450China Tianjin Key Laboratory of Epigenetics for Organ Department in Preterm Infants the Fifth Central Hospital of TianjinTianjin 300450China

Naringin exists in a wide range of Chinese herbal medicine and has proven to possess several pharmacological *** this study,PC12,HepG2 cells,and female Drosophila melanogaster were used to investigate the antioxidative and anti-aging effects of naringin and explore the underlying *** results showed that naringin inhibited H_(2)O_(2)-induced decline in cell viability and decreased,the content of reactive oxygen species in ***,naringin prolonged the lifespan of flies,enhanced the abilities of climbing and the resistance to stress,improved the activities of antioxidant enzymes,and decreased malondialdehyde *** also improved intestinal barrier dysfunction and reduced abnormal proliferation of intestinal stem ***,naringin down-regulated the mRNA expressions of inr,chico,pi 3k,and akt-1,and up-regulated the mRNA expressions of dilp2,dilp3,dilp5,and foxo,thereby activating autophagy-related genes and increasing the number of ***,the mutant stocks assays and computer molecular simulation results further indicated that naringin delayed aging by inhibiting the insulin signaling(IIS)pathway and activating the autophagy pathway,which was consistent with the result of network pharmacological predictions.

关键词： Drosophila melanogaster Insulin signaling(IIS)pathway Naringin PC12 cell HepG2 cell