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基于机器学习的RDX-CMDB推进剂安全性能预测

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四川大学学报(自然科学版) 2025年第1期62卷 228-236页

作者：郭延芝吴艳玲刘润青赵凤起徐司雨蒲雪梅四川大学化学学院成都610064 中北大学环境与安全工程学院太原030051 西安近代化学研究所含能材料全国重点实验室西安710065

为了满足对于固体推进剂安全性能预测的迫切需求,本研究提出了一种基于机器学习的推进剂安全性能预测方法.针对现有推进剂的安全性能数据量不足的问题,本研究引入主动学习混合插值(AL-Mixup)方法对数据进行了增强.综合考虑推进剂原料的... 详细信息

为了满足对于固体推进剂安全性能预测的迫切需求,本研究提出了一种基于机器学习的推进剂安全性能预测方法.针对现有推进剂的安全性能数据量不足的问题,本研究引入主动学习混合插值(AL-Mixup)方法对数据进行了增强.综合考虑推进剂原料的组分种类、含量和颗粒粒度对安全性能的影响,本研究构建了含RDX改性双基(RDX-CMDB)推进剂的摩擦感度与撞击感度预测模型.以28组实验测定获得的RDX-CMDB样本为初始数据集,本研究获得了不同数量的增强样本.经Z-score特征标准化处理后,本研究用10种不同的机器学习算法构建了多种预测模型.以R^(2)、RMSE和MAE作为评价指标,本研究利用十折交叉验证法对比分析了不同数量增强样本及不同机器学习算法的组合的预测能力,最终得到两个性能优异的预测模型,一个是基于支持向量回归算法的摩擦感度预测模型(R^(2)=0.7950),另一个是基于人工神经网络算法的撞击感度预测模型(R^(2)=0.8932).对外部样本的测试结果显示,两个模型的预测精度均超过88%,同样令人满意.本研究首次实现了RDX-CMDB推进剂安全性能的快速预测,可望为此类推进剂的安全使用和配方优化提供理论依据.

关键词： RDX-CMDB推进剂摩擦感度撞击感度机器学习数据增强

Gentiana manshurica Kitagawa prevents acetaminophen-induced acute hepatic injury in mice via inhibiting JNK/ERK MAPK pathway

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World Journal of Gastroenterology 2010年第3期16卷 384-391页

作者： Wang, Ai-yan Lian, Li-Hua Jiang, Ying-Zi wu, yan-ling Nan, Ji-Xing yanbian Univ Key Lab Nat Resource Changbai Mt & Funct Mol Minist Educ Coll Pharm Yanji Jilin Peoples R China

AIM:To investigate the in vivo hepatoprotective effects and mechanisms of Gentiana manshurica Kitagawa (GM) in acetaminophen (APAP)-induced liver injury in ***: GM (200, 150 or 50 mg/kg body weight) or N-acetyl-L-cysteine (NAC; 300 mg/kg body weight) was administrated orally with a single dose 2 h prior to APAP (300 mg/kg body weight) injection in ***: APAP treatment significantly depleted hepatic glutathione (GSH), increased serum aspartate aminot ransferase (AST), alanine aminotransferase (ALT) and malonyldialdehyde (MDA) and 4-hydroxynonenal levels, and decreased hepatic activity of glutathione peroxidase (GSH-px) and superoxide dismutase (SOD). However, the pretreatment of GM signif icantly alleviated APAP-induced oxidative stress by increasing GSH content, decreasing serum ALT, AST and MDA, and retaining the activity of GSH-px and SOD in the liver. Furthermore, GM pretreatment can inhibit caspase-3 activation and phosphorylation of c-Jun-NH2-terminal protein kinase 2 (JNK1/2) and extracellular signalregulated kinase (ERK). GM also remarkably attenuated hepatocyte apoptosis confirmed by the terminal deoxynucleotidyl transferase mediated dUTP nick end-labeling ***: Hepatoprotective effects of GM against APAP-induced acute toxicity are mediated either by preventing the decline of hepatic antioxidant status or its direct anti-apoptosis capacity. These results support that GM is a potent hepatoprotective agent.

关键词： Gentiana manshurica Kitagawa Aceta-minophen Oxidative stress Caspase-3 JNK/ERK MAPK

Interannual Variability of Sea Surface Temperature in the Northern Indian Ocean Associated with ENSO and IOD

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Atmospheric and Oceanic Science Letters 2012年第4期5卷 295-300页

作者： wu yan-ling DU yan ZHANG Yu-Hong ZHENG Xiao-Tong Graduate University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Guang-~.hou 510301 China Ocean University of China Qingdao 266100 China

The Northern Indian Ocean （NIO） sea surface temperature （SST） warming, associated with the E1 Nifio/Southern Oscillations （ENSO） and the Indian Ocean Dipole （IOD） mode, is investigated using the International Comprehensive Ocean-Atmosphere Data Set （ICOADS） monthly data for the period 1979-2010. Statistical analy- ses are used to identify respective contribution from ENSO and IOD. The results indicate that the first NIO SST warming in September-November is associated with an IOD event, while the second NIO SST warming in spring-summer following the mature phase of ENSO is associated with an ENSO event. In the year that IOD co-occurred with ENSO, NIO SST warms twice, rising in the ENSO developing year and decay year. Both short- wave radiation and latent heat flux contribute to the NIO SST variation. The change in shortwave radiation is due to the change in cloudiness. A cloud-SST feedback plays an important role in NIO SST warming. The latent heat flux is related to the change in monsoonal wind. In the first NIO warming, the SST anomaly is mainly due to the change in the latent heat flux. In the second NIO warming, both factors are important.

关键词： El Nifio Indian Ocean Dipole mode sea surface temperature interannual variability

The Interannual Variations of Summer Precipitation in the Northern Indian Ocean Associated with ENSO

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Atmospheric and Oceanic Science Letters 2012年第4期5卷 301-305页

作者： yanG Ya-Li DU yan wu yan-ling HUANG Gang ZHANG Yong-Sheng Graduate University of Chinese Academy of Sciences Beijing 100049 China ~tate Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Guang-~hou 510301 China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia (RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing 100029 China Earth System Science Interdisciplinary Center (ESSIC) University of Maryland USA

Using rainfall data from the Global Precipita- tion Climatology Project （GPCP）, NOAA extended reconstruction sea surface temperature （ERSST）, and NCEP/NCAR reanalysis, this study investigates the interannual variation of summer rainfall southwest of the Indian Peninsula and the northeastern Bay of Bengal associated with ENSO. The composite study indicates a decreased summer rainfall southwest of the Indian Penin- sula and an increase in the northeastern Bay of Bengal during the developing phase, but vice versa during the decay phase of E1 Nifio. Further regression analysis dem- onstrates that abnormal rainfall in the above two regions is controlled by different mechanisms. Southwest of the Indian Peninsula, the precipitation anomaly is related to local convection and water vapor flux in the decay phase of E1 Nifio. The anomalous cyclone circulation at the lower troposphere helps strengthen rainfall. In the northeastern Bay of Bengal, the anomalous rainfall depends on the strength of the Indian southwest summer monsoon （ISSM）. A strong/weak ISSM in the developing/decay phase of E1 Nifio can bring more/less water vapor to strengthen/weaken the local summer precipitation.

关键词： Indian summer monsoon ENSO interannual variability

Inhibition of P2X7R modulates ECM deposition in HSCs and crosstalk with macrophages in liver fibrosis

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中国药理学与毒理学杂志 2019年第10期 772-773页

作者： JIANG Min CUI Ben-wen ZHANG Yu wu yan-ling NAN Ji-xing LIAN Li-hua Key Laboratory for Natural Resource of Changbai Mountain& Functional Molecules Ministry of Education College of Pharmacy Yanbian University

OBJECTIVE Modulation of immune response and reduction of extracellular matrix(ECM)deposition are both essential in the therapy of liver *** P2 X7 R might be a potential therapeutic strategy to treat liver fibrosis, we investigated whether the blockade of P2 X7 R could reverse liver fibrosis and how P2 X7 R is involved in fibrogenesis during hepatic stellate cells(HSCs) and macrophages crosstalk. METHODS In vivo,liver fibrosis model was established by thioacetamide(TAA) intraperitoneal administration in male C57 BL/6 mice. In vitro, LX-2 cells were treated with TGF-β and LPS/ATP respectively. Supernatant from LPS/ATP stimulated THP-1 macrophages were supplemented to LX-2 cells to mimic cellular crosstalk between HSCs and macrophages. RESULTS Blockade of P2 X7 R with its selective antagonist A438079, not only decreased liver injury and ECM deposition but also ameliorated inflammation by inhibiting NLRP3 inflammasome, NF-κB activation and IL-1β production in TAA-induced liver fibrosis. And the recruitment of macrophages, monocytes and granulocytes were also inhibited. In TGF-β-stimulated LX-2 cells,ECM deposition was reduced by the inhibiting of P2 X7 RTLR4-NLRP3 axis. Protein synthesis and cleavage of IL-1β and its m RNA level was dramatically increased by LPS 4 h combined with ATP 30 min than those in HSC treated with LPS or ATP alone. Additionally, LX-2 cells primed with LPS/ATP greatly increased m RNA and protein expression of caspase-1, NLRP3 and P2 x7 R, as well as liver fibrosis markers, α-SMA and typeⅠ*** events were remarkably suppressed by A438079 pretreatment. si RNA against P2 x7 R reduced protein expression of NLRP3 and α-SMA, and suppressed deposition and secretion of type Ⅰ collagen induced by LPS/ATP. Ectopic overexpression of P2 X7 R reduced the threshold of ECM deposition in HSCs induced by TGF-β.Inhibiting upstream receptors of NLRP3 inflammasome,P2 X7 receptor-selective antagonist(A438079), TLR4 inhibitor(CLI-095) reduced

关键词： liver fibrosis hepatic stellate cells macrophages P2x7R IL-1β

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混沌加载PE文件水印数据率改进方法

吉林大学学报（工学版） 2024年第10期54卷 3000-3008页

作者：罗养霞吴燕玲西安财经大学信息学院西安710100

针对PE文件存在水印鲁棒性差和数据率低的不足,本文基于混沌扰动对子水印信息加密,提高了水印的鲁棒性;基于混沌散列把水印信息分散编码到整个代码段中,提高了水印的隐蔽性;应用MPPCT_DF动态图结构,增加图节点编码量,同时每个节点增加... 详细信息

针对PE文件存在水印鲁棒性差和数据率低的不足,本文基于混沌扰动对子水印信息加密,提高了水印的鲁棒性;基于混沌散列把水印信息分散编码到整个代码段中,提高了水印的隐蔽性;应用MPPCT_DF动态图结构,增加图节点编码量,同时每个节点增加一个静态数据域,扩大了信息存储量。基于此,提出一种混沌加载PE文件的动态图水印(CBDW_PE)技术方案,并给出主要组成模块、关键算法,展示系统实现及概念数据模型,最后对算法进行对比和分析。经比较,该技术对剪切、篡改和逆向攻击等具有较好的效果,提高了水印的安全性与隐蔽性,有效改善了PE文件数据率低的问题,便于有意义水印的加载。

关键词：软件水印混沌加密混沌置乱数据嵌入率

Axial emission characteristics of an ionic liquid electrospray thruster with a circular emitter

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Chinese Journal of Aeronautics 2025年第1期38卷 297-305页

作者： Cheng yanG Jiawei LUO Xiangbei wu yan SHEN School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China

Ionic Liquid Electrospray Thrusters(ILETs)are well suited for micro-nano satellite applications due to their small size,low power consumption,and high specific ***,the limited thrust of a single-emitter ILET restricts its use in space *** optimize the performance of ILETs and make them suitable for a wider range of space missions,we designed a Circular-emitter ILET(CILET)to convert a one-dimensional(point)emission into a twodimensional(line)*** CILET can self-organize multiple Taylor cones *** cones were photographed and the axial emission currents were measured under different voltage and pressure difference conditions with a CILET experimental *** emission can be divided into two stable states and one unstable state based on the flow and current *** current in Stable state Ⅰ increases non-linearly with the voltage,while that in Stable state Ⅱ is nearly linear with respect to the *** number of cones increases with the voltage in stable states,while the cones become short and crowded under high-voltage *** variation law of the number of cones can be explained with the self-organization *** variation in the current exhibits a good correlation with the number of *** study demonstrates the feasibility of circular emitters and experimentally indicates that the emission current is improved by approximately two orders of magnitude compared to that of a single capillary.

关键词： Electrospray Ionic liquid thruster Self-organize Emitter Taylor cone

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基于模体的复杂网络测度量研究

物理学报 2013年第16期62卷 511-519页

作者：韩华刘婉璐吴翎燕武汉理工大学理学院武汉430070

针对复杂网络拓扑结构中模体的存在性,在传统的顶点度和边聚类系数定义的基础上,提出了基于模体的顶点度和边度来衡量网络中顶点和边的重要性.用Rand-ESU算法对不同规模的8个网络进行模体检测,验证了网络中模体的存在性,重点分析了Karat... 详细信息

针对复杂网络拓扑结构中模体的存在性,在传统的顶点度和边聚类系数定义的基础上,提出了基于模体的顶点度和边度来衡量网络中顶点和边的重要性.用Rand-ESU算法对不同规模的8个网络进行模体检测,验证了网络中模体的存在性,重点分析了Karate网络和Dolphin网络中模体的结构和特征.用Pearson相关系数衡量基于模体的顶点度与传统顶点度、基于模体的边度与边聚类系数的相关性,仿真分析结果表明相关性大小与模体种类有关,基于模体的顶点度和边度是对原定义的一种改进和拓展,更全面地刻画了顶点和边在网络中的重要性.

关键词：模体顶点度边度 Pearson相关系数

Suppression of PD-1 gene overexpression by thio-heterocyclic naphthalimides mediating apoptosis of cancer cells

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Suppression of PD-1 gene overexpression by thio-heterocyclic...