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Deep Learning and Network Analysis:Classifying and Visualizing Geologic Hazard Reports

Journal of Earth Science 2024年第4期35卷 1289-1303页

作者： Wenjia Li Liang Wu Xinde Xu zhong xie Qinjun Qiu Hao Liu Zhen Huang Jianguo Chen School of Geography and Information Engineering China University of GeosciencesWuhan430078China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan430078China School of Computer Science China University of GeosciencesWuhan430078China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen518034China Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering China Three Gorges UniversityYichang443002China Wuhan Geomatics Institute Wuhan430074China Faculty of Earth Resources China University of GeosciencesWuhan430074China

If progress is to be made toward improving geohazard management and emergency decision-making,then lessons need to be learned from past geohazard information.A geologic hazard report provides a useful and reliable source of information about the occurrence of an event,along with detailed information about the condition or factors of the *** such reports,however,can be a challenging process because these texts are often presented in unstructured long text formats,and contain rich specialized and detailed *** text classification is commonly used to mine disaster text data in open domains(e.g.,news and microblogs).But it has limitations to performing contextual long-distance dependencies and is insensitive to discourse *** deficiencies are most obviously exposed in long text ***,this paper uses the bidirectional encoder representations from Transformers(BERT),to model long ***,utilizing a softmax layer to automatically extract text features and classify geohazards without manual *** latent Dirichlet allocation(LDA)model is used to examine the interdependencies that exist between causal variables to visualize *** proposed method is useful in enabling the machine-assisted interpretation of text-based ***,it can help users visualize causes,processes,and other geohazards and assist decision-makers in emergency responses.

关键词： geologic hazard network analysis latent dirichlet allocation text classification deep learning

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Giant piezotronic effect in ferroelectric field effect transistor

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Nano Research 2024年第9期17卷 8465-8471页

作者： Haiming Zhang Mengshuang Chi Shidai Tian Tian Liang Jitao Liu Xiang Zhang Lingyu wan zhong Lin wang Junyi Zhai Center on Nanoenergy Research School of Physical Science&TechnologyGuangxi UniversityNanning 530004China Beijing Key Laboratory of Micro-Nano Energy and Sensor Center for High-Entropy Energy and SystemsBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of ScienceBeijing 100049China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Georgia Institute of Technology AtlantaGA 30332USA

The piezotronics effect utilizes a piezopotential to modulate and control current in *** materials,as a type of piezoelectric materials,possess piezoelectric coefficients that are significantly larger than those found in conventional piezoelectric ***,we propose a strain modulated ferroelectric field-effect transistor(St-FeFET)utilizing external strain instead of gate voltage to achieve ferroelectric modulation,which eliminates the need for gate *** applying a very small strain(0.01%),the St-FeFET can achieve a maximum on-off current ratio of 1250%and realizes a gauge factor(GF)of 1.19×10^(6),which is much higher than that of conventional strain *** work proposes a new method for realizing highly sensitive strain sensors and presents innovative approaches to the operation methods of ferroelectric field-effect transistors as well as potential applications for coupling of strain sensors and various devices across different fields.

关键词： ferroelectric field-effect transistors piezotronics [Pb(Mg_(1/3)Nb_(2/3))O_(3)]_((1-x)^(-))[PbTiO_(3)]_(x)(PMN-PT) strain sensors

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位移浅水内孤立波

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计算力学学报 2019年第3期36卷 297-303页

作者：吴锋姚征孙雁钟万勰大连理工大学工程力学系大连116024 大连海事大学交通运输装备与海洋工程学院大连116026 上海交通大学船舶海洋与建筑工程学院上海200240

研究两层浅水系统中的内孤立波,该系统由两层常密度不可压缩无黏性水组成。利用Lagrange坐标和Hamilton原理,推导了两层浅水系统的位移浅水内波方程,并进一步导出了两层浅水系统的位移内孤立波解。数值实验表明,位移内孤立波与经典的Kd... 详细信息

研究两层浅水系统中的内孤立波,该系统由两层常密度不可压缩无黏性水组成。利用Lagrange坐标和Hamilton原理,推导了两层浅水系统的位移浅水内波方程,并进一步导出了两层浅水系统的位移内孤立波解。数值实验表明,位移内孤立波与经典的KdV内孤立波吻合很好,说明Lagrange坐标和Hamilton方法适用于内波分析,可以为构造内波分析的保辛方法提供一种途径。

关键词：内孤立波 Lagrange坐标 Hamilton原理

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保辛-保能的数值积分

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应用数学和力学 2014年第8期35卷 831-837页

作者：孙雁高强钟万勰上海交通大学船舶海洋与建筑工程学院工程力学系上海200240 大连理工大学工程力学系工业装备结构分析国家重点实验室(大连理工大学) 辽宁大连116024

针对Hamilton动力系统时变非线性问题,应用混合能变分原理,提出Hamilton系统的离散积分保辛算法.在此基础上,对Hamilton系统引入参变量,设计非线性问题迭代算法格式,通过对参变量的调整,在积分格点上实现了Hamilton系统数值积分保辛同... 详细信息

针对Hamilton动力系统时变非线性问题,应用混合能变分原理,提出Hamilton系统的离散积分保辛算法.在此基础上,对Hamilton系统引入参变量,设计非线性问题迭代算法格式,通过对参变量的调整,在积分格点上实现了Hamilton系统数值积分保辛同时保能的目标.

关键词：保辛能量守恒 Hamilton系统区段混合能参变量

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线性二次最优控制的精细积分法

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自动化学报 2001年第2期27卷 166-173页

作者：钟万勰大连理工大学工业装备结构分析国家重点实验室大连116023

LQ控制虽然是最优控制的最基本问题 ,但其数值求解仍有很多问题 .黎卡提微分方程的精细积分法利用黎卡提方程的解析特点 ,求出计算机上高度精密的解 ,并已证明误差在计算机倍精度数的误差范围之外 .这对于 Kalman- Bucy滤波 ,LQG问题以... 详细信息

LQ控制虽然是最优控制的最基本问题 ,但其数值求解仍有很多问题 .黎卡提微分方程的精细积分法利用黎卡提方程的解析特点 ,求出计算机上高度精密的解 ,并已证明误差在计算机倍精度数的误差范围之外 .这对于 Kalman- Bucy滤波 ,LQG问题以及 H∞ 控制及滤波等都可运用 ,精细积分还求解了反馈后的状态微分方程 .数例验证了其高精度特性 .

关键词：黎卡提方程精细积分最优控制线性二次控制

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A general climatology of categorized Martian ionospheric irregularities

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Science China Earth Sciences 2024年第10期67卷 3302-3325页

作者： Xin wan Jiahao zhong Yongqiang HAO Chao XIONG Hui wanG Yutian CAO Jun CUI Yiwen LIU Qiaoling LI Jiawei KUAI Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China Key Laboratory of Tropical Atmosphere-Ocean System Ministry of EducationZhuhai 519082China Department of Space Physics College of Electronic InformationLuojia LaboratoryWuhan UniversityWuhan 430079China School of Physics and Electronic Information Shangrao Normal UniversityShangrao 334001China School of Petroleum China University of Petroleum-Beijing at KaramayKaramay 834000China College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A climatological survey of Martian ionospheric plasma density irregularities was conducted by exploring the in-situ measurements of the Mars Atmosphere and Volatile EvolutioN(MAVEN) spacecraft. The irregularities were first classified as enhancement, depletion, and oscillation. By checking the simultaneous magnetic field fluctuation, the irregularities have been classified into two types: with or without magnetic signatures. The classified irregularities exhibit diverse global occurrence patterns, as those with magnetic signatures tend to appear near the periphery of the crustal magnetic anomaly(MA), and those without magnetic signatures prefer to appear either inside of the MA or outside of the MA, depending on the type and solar zenith angle. Under most circumstances, the irregularities have a considerable occurrence rate at altitudes above the ionospheric dynamo height(above 200 km), and the magnetization state of the ions seems irrelevant to their occurrence. In addition, the irregularities do not show dependence on magnetic field geometry, except that the enhancement without magnetic signatures favors the vertical field line, implying its equivalence to the localized bulge. Other similarities and discrepancies exist in reference to previous studies. We believe this global survey complements previous research and provides crucial research clues for future efforts to clarify the nature of the Martian ionospheric irregularities.

关键词： Mars MAVEN Ionosphere Ionospheric irregularities Crustal magnetic anomaly Plasma

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连续系统的界带分析方法

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计算力学学报 2013年第6期30卷 749-756,776页

作者：姚征张洪武钟万勰大连海事大学交通运输装备与海洋工程学院大连116026 大连理工大学工业装备结构分析国家重点实验室大连116024

基于分析结构力学提出的界带分析方法,将子结构间的分界面延拓为有一定宽度的分界带/分界域,从而可以用于分析计算结构的非局部效应。界带分析方法首先在离散结构的分析计算中取得了成功,从而验证了该套理论算法的准确性。离散结构按界... 详细信息

基于分析结构力学提出的界带分析方法,将子结构间的分界面延拓为有一定宽度的分界带/分界域,从而可以用于分析计算结构的非局部效应。界带分析方法首先在离散结构的分析计算中取得了成功,从而验证了该套理论算法的准确性。离散结构按界带宽度(影响域范围)划分子结构,因而限制了子结构区段积分计算的最小步长;而连续系统则要求可以实现任意步长的积分运算。通过引入步进的计算方法,界带分析方法可以实现任意步长的积分计算,进而可以解决连续系统的积分问题。通过数值算例验证了连续系统的界带分析方法的准确性和可行性,也为进一步研究该套计算方法在分析动力学中的应用打下基础。

关键词：界带分析子结构辛方法分析结构力学

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Microbial Fertilizer: A Sustainable Strategy for Medicinal Plants Production

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1221-1236页

作者： Chuang Liu Jing xie Hao Liu Can zhong Gen Pan Shuihan Zhang Jian Jin Hunan Academy of Chinese Medicine Hunan University of Chinese MedicineChangsha410036China Institute of Chinese Medicine Resources Hunan Academy of Chinese MedicineChangsha410013China

Medicinal plants have aroused considerable interest as an alternative to chemical drugs due to the beneﬁcial effects of their active secondary ***,the extensive use of chemical fertilizers and pesticides in pursuit of yield has caused serious pollution to the environment,which is not conducive to sustainable devel-opment in theﬁeld of medicinal *** fertilizers are a type of“green fertilizer”containing speciﬁc microorganisms that can improve the soil microbial structure,enhance plant resistance to biological and abiotic stresses,and increase the yield of medicinal *** root exudates of medicinal plants attract different micro-organisms to the rhizosphere,which then migrate further to the plant *** microbes can increase the levels of soil nutrients,and improve the physical and chemical properties of soil through nitrogenﬁxation,and phosphorus and potassium *** addition,soil microbes can promote the synthesis of hormones that increase plant growth and the accumulation of active compounds,eventually improving the quality of med-icinal *** 2022,the total value of the global microbial fertilizer market was$4.6 billion and is estimated to reach$10.36 billion by *** this review,we have summarized the types of microbial fertilizers,the coloniza-tion and migration of microorganisms to plant tissues,and the beneﬁcial effects of microbial *** addi-tion,the prospects of developing microbial fertilizers and their application for medicinal plants have also been *** aims to provide a reference for the rational application of microbial fertilizers in theﬁeld of med-icinal plants and the green and sustainable development of medicinal plant resources.

关键词： Microbial fertilizers market overview rhizosphere microorganisms endophytic bacteria beneﬁcial effects

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The association and underlying mechanism of the digit ratio(2D:4D)in hypospadias

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Asian Journal of Andrology 2024年第4期26卷 356-365页

作者： Yu Ding Zu-Quan Chen Wen-Feng Pan Hao-Jie Chen Min Wu Yi-Qing Lyu Hua xie Yi-Chen Huang zhong-zhong Chen Fang Chen Department of Urology Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China Urogenital Development Research Center Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China Clinical Research Center for Hypospadias Pediatric CollegeShanghai Jiao Tong University School of MedicineShanghai 200062China.

The second-to-fourth digit(2D:4D)ratio is thought to be associated with prenatal androgen ***,the relationship between the 2D:4D ratio and hypospadias is poorly understood,and its molecular mechanism is not *** this study,by analyzing the hand digit length of 142 boys with hypospadias(23 distal,68 middle,and 51 proximal)and 196 controls enrolled in Shanghai Children’s Hospital(Shanghai,China)from December 2020 to December 2021,we found that the 2D:4D ratio was significantly increased in boys with hypospadias(P<0.001)and it was positively correlated with the severity of the *** was further verified by the comparison of control mice and prenatal low testosterone mice model obtained by knocking out the risk gene(dynein axonemal heavy chain 8[DNAH8])associated with ***,the discrepancy was mainly caused by a shift in *** characterization of a mouse model validated that low testosterone levels during pregnancy can impair the growth and development of *** mechanistic explorations revealed that during the androgen-sensitive window,the downregulation of the androgen receptor(AR)caused by low testosterone levels,as well as the suppressed expression of chondrocyte proliferation-related genes such as Wnt family member 5a(Wnt5a),Wnt5b,Smad family member 2(Smad2),and Smad3;mitochondrial function-related genes in cartilage such as AMP-activated protein kinase(AMPK)and nuclear respiratory factor 1(Nrf-1);and vascular development-related genes such as myosin light chain(MLC),notch receptor 3(Notch3),and sphingosine kinase 1(Sphk1),are responsible for the limitation of 4D growth,which results in a higher 2D:4D ratio in boys with hypospadias via decreased endochondral *** study indicates that the ratio of 2D:4D is a risk marker of hypospadias and provides a potential molecular mechanism.

关键词： androgen receptor digit ratio(2D:4D) endochondral ossification hypospadias testosterone level

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Research on thermal insulation materials properties under HTHP conditions for deep oil and gas reservoir rock ITP-Coring

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Petroleum Science 2024年第4期21卷 2625-2637页

作者： Zhi-Qiang He He-Ping xie Ling Chen Jian-Ping Yang Bo Yu Zi-Jie Wei Ming-zhong Gao State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and Hydropower Sichuan University Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green Energy College of Civil and Transportation Engineering Shenzhen University School of Mechanical Engineering Sichuan University College of Polymer Science and Engineering Sichuan University

Deep oil and gas reservoirs are under high-temperature conditions, but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability, resulting in distorted resource assessments. The development of in situ temperaturepreserved coring(ITP-Coring) technology for deep reservoir rock is urgent, and thermal insulation materials are key. Therefore, hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials) were proposed as thermal insulation materials. The materials properties under coupled hightemperature and high-pressure(HTHP) conditions were tested. The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased; additionally,increasing temperature accelerated the process. High temperatures directly caused the thermal conductivity of the materials to increase; additionally, the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity. High temperatures weakened the matrix, and high pressures destroyed the HGM, which resulted in a decrease in the tensile mechanical properties of the materials. The materials entered the high elastic state at 150.C, and the mechanical properties were weakened more obviously, while the pressure led to a significant effect when the water absorption was above 10%. Meanwhile, the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86% at 100.C and 100 MPa, respectively, which meet the application requirements of the self-designed coring device. Finally, K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100.C and 100 MPa. To further improve the materials properties, the interface layer and EP matrix should be optimized. The results can provide references for the optimization and engineering application of materials and thus technical su

关键词： Deep oil and gas reservoir rock In situ temperature-preserved coring (ITP-Coring) Hollow glass microsphere/epoxy resin thermal insulation materials (HGM/EP materials) High-temperature and high-pressure (HTHP) Physical and mechanical properties

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