检索结果-南通市图书馆

Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,Mexico

引用

Journal of Mountain Science 2024年第6期21卷 1954-1977页

作者： víctor SOTO Carlos M.WELSH R. Kenji YOSHIKAWA Hugo DELGADO GRANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A stability evaluation method for deep-seated toppling in the upper Lancang river,Southwestern China

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2388-2410页

作者： Yibing Ning Huiming Tang Jianbing Peng Yanjun Shen John v.Smith Bocheng Zhang College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China Academy of Yellow River Sciences of Shaanxi Province Chang’an UniversityXi’an710054China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China School of Engineering RMIT UniversityMelbourne3001Australia

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in *** slope deformation is initiated by river downcutting and evolves distinctive characteristics with a depth of river *** this study,we propose a system for evaluating the stability of deep-seated toppled slopes in different evolutionary *** system contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation *** on the mechanical and kinematic analysis of slope blocks,the specific stage of slope movement can be identified in the field through outcrop mapping,in situ tests,surface displacement monitoring,and adit and borehole *** stability evaluation methods are established based on the limiting equilibrium theory and the strain compatibility between the undisturbed zone and the toppled ***,several sample slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation *** results indicate that intense tectonic activity and rapid river incision lead to a maximum principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deformations along the river *** considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deformation can be recognized by the layer symmetry configuration after the free rotation of the deflected *** toppled rock blocks mainly suffer sliding failures beyond the layer symmetry *** factor of safety of the K73 rockslide decreased from 1.17 to 0.87 by considering the development of the potential sliding surface and the toesaturated zone.

关键词： Stability evaluation Deep-seated toppling Evolutionary process Reservoir impoundment Rock slope

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An examination of thematic research,development,and trends in remote sensing applied to conservation agriculture

引用

International Soil and Water Conservation Research 2024年第1期12卷 77-95页

作者： Zobaer Ahmed Aaron Shew Lawton Nalley Michael Popp v.Steven Green Kristofor Brye Center for Advanced Spatial Technologies University of ArkansasFayettevilleARUSA Environmental Dynamics Program University of ArkansasFayettevilleARUSA Department of Agricultural Economics and Agribusiness University of ArkansasFayettevilleARUSA College of Agriculture Arkansas State UniversityJonesboroARUSA University of Arkansas System Division of Agriculture Little RockARUSA Department of Crop Soiland Environmental SciencesUniversity of ArkansasFayettevilleARUSA

Conservation agriculture seeks to reduce environmental degradation through sustainable management of agricultural *** the 1990s,agricultural research has been conducted using remote sensing technologies;however,few previous reviews have been conducted focused on different conservation management *** of the previous literature has focused on the application of remote sensing in agriculture without focusing exclusively on conservation practices,with some only providing a narrative review,others using biophysical remote sensing for quantitative estimates of the bio-geo-chemical-physical properties of soils and crops,and few others focused on single agricultural management *** paper used the preferred reporting items for systematic review(PRISMA)methodology to examine the last 30 years of thematic research,development,and trends associated with remote sensing technologies and methods applied to conservation agriculture research at various spatial and temporal scales.A set of predefined key concepts and keywords were applied in three databases:Scopus,Web of Science,and Google Scholar.A total of 188 articles were compiled for initial examination,where 68 articles were selected for final analysis and grouped into cover crops,crop residue,crop rotation,mulching,and tillage *** on conservation agriculture research using remote sensing have been increasing since 1991 and peaked at 10 publications in *** the 68 articles,94%used a pixel-based,while only 6%used an object-based classification *** to 2005,tillage practices were abundantly studied,then crop residue was a focused theme between 2004 and *** 2012 to 2020,the focus shifted again to cover *** spectral indices were used in 76%of the 68 *** examination offered a summary of the new potential and identifies crucial future research needs and directions that could improve the contribution of remote sensing to the provision of long-term operat

关键词： Remote sensing Conservation agriculture Classification algorithm Spatial resolution Satellite Spectral indices PRISMA

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Review on dynamic analysis of road pavements under moving vehicles and plane strain conditions

引用

Journal of Road Engineering 2024年第1期4卷 54-68页

作者： Edmond v.Muho Niki D.Beskou Department of Disaster Mitigation for Structures Tongji UniversityShanghai 200092China Department of Civil Engineering University of the PeloponnesePatras 26334Greece School of Science and Technology Hellenic Open UniversityPatras 26335Greece

This paper reviews works on the dynamic analysis of flexible and rigid pavements under moving vehicles on the basis of continuum-based plane strain models and linear *** purpose of this review is to provide in-formation about the existing works on the subject,critically discuss them and make suggestions for further *** reviewed papers are presented on the basis of the various models for pavement-vehicle systems and the various methods for dynamically analyzing these *** pavements are modeled by a homogeneous or layered half-plane with isotropic or anisotropic and linear elastic,viscoelastic or poroelastic material *** pavements are modeled by a beam or plate on a homogeneous or layered half-plane with material properties like the ones for flexible *** vehicles are modeled as concentrated or distributed over a finite area loads moving with constant or time dependent *** above pavement-vehicle models are dynamically analyzed by analytical,analytical/numerical or purely numerical methods working in the time or frequency *** examples are presented to illustrate the models and methods of analysis,demonstrate their merits and assess the effects of the various parameters on pavement *** paper closes with con-clusions and suggestions for further research in the *** significance of this research effort has to do with the presentation of the existing literature on the subject in a critical and easy to understand way with the aid of representative examples and the identification of new research areas.

关键词： Flexible pavements Rigid pavements Moving vehicles Plane strain models Dynamic analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Output feedback adaptive super twisting sliding mode control for quadrotor UAvs

引用

Control Theory and Technology 2024年第1期22卷 92-105页

作者： Oscar Salas-Peña Jesus DeLeón-Morales Susana v.Gutiérrez-Martínez École Centrale de Nantes-LS2N UMR 6004 CNRS44300NantesFrance Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo León66451San Nicolás de Los GarzaMexico

In this paper, a sliding mode control with adaptive gain combined with a high-order sliding mode observer to solve the tracking problem for a quadrotor UAv is addressed, in presence of bounded external disturbances and parametric uncertainties. The high order sliding mode observer is designed for estimating the linear and angular speed in order to implement the proposed scheme. Furthermore, a Lyapunov function is introduced to design the controller with the adaptation law, whereas an analysis of finite time convergence towards to zero is provided, where sufficient conditions are obtained. Regarding previous works from literature, one important advantage of proposed strategy is that the gains of control are parameterized in terms of only one adaptive parameter, which reduces the control effort by avoiding gain overestimation. Numerical simulations for tracking control of the quadrotor are given to show the performance of proposed adaptive control–observer scheme.

关键词： Adaptive super twisting controller High-order sliding modes observer UAv

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geochemistry and depositional environment of fuchsite quartzites from Sargur Group,western Dharwar Craton,India

引用

Acta Geochimica 2024年第3期43卷 555-570页

作者： C.S.Sindhuja G.Harshitha C.Manikyamba K.S.v.Subramanyam CSIR(Council of Scientific and Industrial Research)-National Geophysical Research Institute(NGRI) Uppal RoadHyderabad 500007India

Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar Craton including the oldest(~3.3 Ga)Sargur Group of western Dharwar *** present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation *** major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and *** geochemical com-positions are characterized by high SiO_(2),Al_(2)O_(3),low MgO,CaO,strongly enriched Cr(1326–6899 ppm),Ba(1165–3653 ppm),Sr(46–210 ppm),v(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(UCC).The UCC normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/Sm)UCC=0.33–0.95]compared to heavy REE[(Gd/Yb)_(UCC)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered *** overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin *** comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by Cr-richfluids released during high-grade metamorphism of associated ultramafic *** Sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of Cr-richfluids and the formation of fuchsite quartzite during or after the *** sug-gest a pre-existing stable crust prior to the Sargur Group and the link between orogenic events and various mineral deposits in the Dharwar Craton.

关键词： Dharwar Craton Ghattihosahalli Fuchsite quartzite Provenance Depositional setting

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Lithium:A review of applications,occurrence,exploration,extraction,recycling,analysis,and environmental impact

引用

Geoscience Frontiers 2024年第5期15卷 1-46页

作者： v.Balaram M.Santosh M.Satyanarayanan N.Srinivas Harish Gupta CSIR-National Geophysical Research Institute(NGRI) Hyderabad 500007India School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA 5005Australia Department of Environmental Studies GITAM Institute of ScienceGandhi Institute of Technology&Management(GITAM)Visakhapatnam 530045India Department of Civil Engineering Osmania UniversityHyderabad 500007India

The energy transition challenges faced by modern civilization have significantly enhanced the demand for critical metals like lithium resulting in improved methods to explore,extract,and utilize these *** this comprehensive review,we discuss the different types of lithium resources,factors,and mechanisms controlling lithium enrichment in various geological settings including terrestrial and marine *** exploration strategies including geological,geophysical,mineralogical,geochemical,and remote sensing techniques including drone-based techniques for lithium exploration studies in different terranes are *** overview of the mining techniques,including beneficiation and extraction,and their principles,mechanisms,operations,and comparison of the various approaches and compatibility with different types of lithium deposits for obtaining maximum yield are *** isotopic studies are useful in understanding geological processes such as past weathering events and riverine input into the oceans,as well as in understanding the source of lithium in diverse types of *** also highlight the recent developments in other areas such as recycling,environmental impact,and state-of-the-art analytical techniques for determining lithium in different lithium ore deposits and other geological *** overview provides the latest developments and insights in the various sectors related to lithium and prompt further developments to meet the growing demand for this valuable metal as the world transforms to clean energy.

关键词： Lithium minerals Pegmatite Lithium brine deposits Lithium sedimentary deposits Exploration techniques

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hybrid Optimization Algorithm for Handwritten Document Enhancement

引用

Computers, Materials & Continua 2024年第3期78卷 3763-3786页

作者： Shu-Chuan Chu Xiaomeng Yang Li Zhang václav Snášel Jeng-Shyang Pan College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao266590China School of Information and Control Engineering Qingdao University of TechnologyQingdao266520China Faculty of Electrical Engineering and Computer Science VŠB-TU OstravaOstrava70080Czech Republic Department of Information Management Chaoyang University of TechnologyTaichung41349Taiwan

The Gannet Optimization Algorithm (GOA) and the Whale Optimization Algorithm (WOA) demonstrate strong performance;however, there remains room for improvement in convergence and practical applications. This study introduces a hybrid optimization algorithm, named the adaptive inertia weight whale optimization algorithm and gannet optimization algorithm (AIWGOA), which addresses challenges in enhancing handwritten documents. The hybrid strategy integrates the strengths of both algorithms, significantly enhancing their capabilities, whereas the adaptive parameter strategy mitigates the need for manual parameter setting. By amalgamating the hybrid strategy and parameter-adaptive approach, the Gannet Optimization Algorithm was refined to yield the AIWGOA. Through a performance analysis of the CEC2013 benchmark, the AIWGOA demonstrates notable advantages across various metrics. Subsequently, an evaluation index was employed to assess the enhanced handwritten documents and images, affirming the superior practical application of the AIWGOA compared with other algorithms.

关键词： Metaheuristic algorithm gannet optimization algorithm hybrid algorithm handwritten document enhancement

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effect of proton irradiation on the optical properties of thermal control coating based on polystyrene with silica filler

引用

Propulsion and Power Research 2024年第1期13卷 1-11页

作者： N.I.Cherkashina v.I.Pavlenko M.M.Mikhailov A.N.Lapin S.A.Yuriev R.v.Sidelnikov D.S.Romanyuk Belgorod State Technological University named after v.G.Shoukhov Kostyukov Str.46Belgorod 308012Russia Tomsk State University of Control Systems and Radioelectronics 40Prospect LeninaTomsk 634050Russia

This paper presents the results of studying the surface properties changes of a ther-moregulating coating based on polystyrene and silicaﬁller after proton irradiation with an en-ergy of 50 kev at afluence of 3�1015 cm�*** proton irradiation,the values of the contact angle of wetting with water increase by 3.5%and 14.9%for polystyrene and the coating,*** free surface energy(energy of the surface layer)of polystyrene and the coat-ings before and after proton irradiation was calculated using the Owens-Wendt-Rabel-Kaelble *** was a signiﬁcant increase in the polarity of the polystyrene surface(gp increased by a factor of 2.2)after proton *** the coating,an increase in gp by a factor of 3.89 was observed after proton *** changes in the coating were presented by IR Fourier spectroscopy.A slight decrease in the absorption intensity of all characteristic bands compared to the unirradiated sample was *** was found that the irradiation of the coating with protons led to the formation of macromolecules with hydroxyl,carbonyl,and carboxyl bonds,as well as the formation of dimeric and oligomeric siloxane *** was also found that after irradiation of a pure polystyrene sample with protons,the value of the solar absorption as increased by only 4.2%;whereas for the coating with silicaﬁller,the value of as increased by 28.6%.

关键词： Thermal control coating Proton irradiation Hydrophobicity Free surface energy Radiation crosslinking

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

MicroRNAs as potential diagnostic biomarkers for bipolar disorder

引用

Neural Regeneration Research 2025年第6期20卷 1681-1695页

作者： Bridget Martinez Philip v.Peplow Department of Pharmacology University of Nevada-RenoRenoNVUSA Department of Medicine University of Nevada-RenoRenoNVUSA Department of Anatomy University of OtagoDunedinNew Zealand

Abnormal expression of microRNAs is connected to brain development and disease and could provide novel biomarkers for the diagnosis and prognosis of bipolar disorder. We performed a PubMed search for microRNA biomarkers in bipolar disorder and found 18 original research articles on studies performed with human patients and published from January 2011 to June 2023. These studies included microRNA profiling in bloodand brain-based materials. From the studies that had validated the preliminary findings,potential candidate biomarkers for bipolar disorder in adults could be miR-140-3p,-30d-5p,-330-5p,-378a-5p,-21-3p,-330-3p,-345-5p in whole blood, miR-19b-3p,-1180-3p,-125a-5p, let-7e-5p in blood plasma, and miR-7-5p,-23b-5p,-142-3p,-221-5p,-370-3p in the blood serum. Two of the studies had investigated the changes in microRNA expression of patients with bipolar disorder receiving treatment. One showed a significant increase in plasma miR-134 compared to baseline after 4 weeks of treatment which included typical antipsychotics, atypical antipsychotics, and benzodiazepines. The other study had assessed the effects of prescribed medications which included neurotransmitter receptorsite binders(drug class B) and sedatives, hypnotics, anticonvulsants, and analgesics(drug class C) on microRNA results. The combined effects of the two drug classes increased the significance of the results for miR-219 and-29c with miR-30e-3p and-526b* acquiring significance. MicroRNAs were tested to see if they could serve as biomarkers of bipolar disorder at different clinical states of mania, depression, and euthymia. One study showed that upregulation in whole blood of miR-9-5p,-29a-3p,-106a-5p,-106b-5p,-107,-125a-3p,-125b-5p and of miR-107,-125a-3p occurred in manic and euthymic patients compared to controls, respectively, and that upregulation of miR-106a-5p,-107 was found for manic compared to euthymic patients. In two other studies using blood plasma,downregulation of miR-134 was observed i

关键词： biomarker bipolar disorder blood leukocytes blood plasma blood plasma extracellular vesicles/exosomes blood serum brain tissue brain tissue extracellular vesicles/exosomes lymphoblastoid cell lines microRNA neural progenitor cells whole blood

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：