检索结果-南通市图书馆

Possible effect of ENSO on annual sediment discharge of debris flows in the Jiangjia Ravine based on Morlet wavelet transforms

引用

International Journal of Sediment Research 2008年第3期23卷 267-274页

作者： J. H. ZHANG1, f. Q. WEI2, S. Z. LIU3, C. GAO41 Dr., Research scientist, Hainan Meteorological Science Institute, South-Sea Meteorology & Disaster Mitigation Research Key Laboratory, Haikou, China, No. 60 Haifu Road, Haikou, China, 2 Dr., Research scientist, 3 Research scientist,4 Dr.,Institute of Mountain Hazards and Environment, CAS, No. 9, Sec. 4, South Renmin Road, Chengdu, China [a]Dr. Research scientist Hainan Meteorological Science Institute South-Sea Meteorology & Disaster Mitigation Research Key Laboratory Haikou China No. 60 Haifu Road Haikou China [b]Dr. Research scientist [c]Research scientist Institute of Mountain Hazards and Environment CAS No. 9 Sec. 4 South Renmin Road Chengdu China [d]Dr. Research scientist Institute of Mountain Hazards and Environment CAS No. 9 Sec. 4 South Renmin Road Chengdu China

The multi-time-scale structures of an annual sediment discharge series of debris flow in the Jiangjia Ravine and the Southern Oscillation index are analysed using the method of Morlet wavelet transformations. The possible effects of El Nio episodes on the annual sediment discharge are discussed by comparing the period variations of ENSO and the discharge. The results show that the annual sediment discharge series of debris flow is related to El Nio episodes. Generally, the annual sediment discharge of debris flow is less than usual during an El Nino episode and debris flow is less active. On the contrary, the annual sediment discharge of debris flows is greater than usual during a La Nia episode and debris flows are more frequent. There is a relationship between the annual sediment discharges of debris flow in the Jiangjia Ravine and the summer Southern Oscillation index, with both having quasi-periodic variations of 2 and 5–6 years.

关键词： Debris flow ENSO Wavelet transform Periodic variation

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Modified Gain Extended Kalman filter with Application to Angles only Underwater Passive Target Tracking

Modified Gain Extended Kalman Filter with Application to Ang...

引用

1998 fourth International Conference Signal Processing

作者： S.KOTESWARA RAO scientist’f’ Naval Science and Technological lab

＜正＞Modified Gain Extended Kalman filter（MGEKf） developed by Song and Speyer [1]was proven to be suitable algorithm for angles only passive target tracking applications in *** this algorithm is extended with approximately modified gains,which are numerically stable and accurate[3].In this paper,this improved MGEKf algorithm is explored for underwater applications with some *** underwater,the noise in the measurements is very high,turning rate of the platforms is low and speed of the platforms is also low when compared with the missiles in air. These characteristics of the platform are studied in detail and the algorithm is modified suitably for tracking applications in ***-Carlo simulated results for one typical scenario is presented for the purpose of explanation. from the results it is observed that this algorithm is suitable for underwater passive target tracking using angles only measurements.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

POSITIVE SOLUTIONS fOR NONHOMOGENEOUS ELLIPTIC EQUATIONSWITH CRITICAL GROWTH ON R^(2)

引用

Acta Mathematica Scientia 1998年第2期18卷 124-138页

作者：周焕松 Acad Sinica Wuhan Inst Phys & Math Young Scientist Lab Math Phys Wuhan 430071 Peoples R China

Let f(x, t): R2×R→ R be a C2-function with respect to t∈R, f(x,0) =0, f(x, t) ~ebt2 as t→+∞ for somc b>0. Under suitable conditions on f(x, t), author shows that for g∈L2 (R2), g(x)≥ 0, the following semilinear clliptic problem:has at least two distinct positive solutions for any λ∈(0, λ*), at least one positive solution for any λ∈ [λ*, λ*] and has no positive solntion for all λ>λ*. It is also proved that λ*≤λ*< +∞.

关键词： Positive solntion elliptic equations critical growth.

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

Properties of flyash based wood geopolymer composite

引用

Low-carbon Materials and Green Construction 2023年第1期1卷 391-404页

作者： B.S.Mamatha D.Sujatha D.N.Uday M.C.Kiran scientist E. Institute of Wood Science and TechnologyGoIBangaloreIndia scientist f. Institute of Wood Science and TechnologyGoIBangaloreIndia

Geopolymers are inorganic adhesive synthesized from industrial waste such as fly ash thus the development of wood geopolymer composite would be a low carbon footprint ***,being a non-formaldehyde adhesive can be used as an alternative binder for wood based composites where environmentally friendly and sustainability of product is *** this study flyash as precursor is been used in the development of wood geopolymer composite *** is activated with a combination of sodium hydroxide and sodium silicate solutions at a weight ratio of 1:2.5 for geopolymer *** study investigated the properties of wood geopolymer composite made with ratios of wood particle to flyash percentage(23/77),(37/62),(44/55),(50/50)and(57/43).Geopolymer formation was observed by X-ray Diffraction(XRD)and fourier transform infrared spectroscopy(fTIR).Influence of wood particles in wood geopolymer composite were observed by Scanning electron *** study shows that the water absorption and thickness selling properties of all the formulations of wood geopolymer composites are comparable with the medium density particle board and cement-bonded particleboard according to the IS:3087-2005 standard and IS:12406:*** mechanical properties and good bond strength was obtained by the composite containing 23%wood particle ratio with 77%percent ***,still improvement in mechanical properties is needed to achieve the mechanical properties comparable to cement bonded particle board.

关键词： Geopolymer Composite Wood particle Inorganic adhesive flyash

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

Experimental Investigation on the Performance of Armour Grade Q&T Steel Joints fabricated by flux Cored Arc Welding with Low Hydrogen ferritic Consumables

引用

Journal of Materials Science & Technology 2009年第5期25卷 583-591页

作者： G.Magudeeswaran V.Balasubramanian G.Madhusudhan Reddy G.Gopalakrishnan Metal Joining Research Center(MJRC) Sri Ramakrishna Engineering CollegeN.G.G.O Colony-Post Centre for Materials Joining&Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University scientist-f Metal Joining SectionDefence Metallurgical Research Laboratory(DMRL)Kanchanbagh(P.O)

Quenched and Tempered （Q＆T） steels are widely used in the construction of military vehicles due to its high strength to weight ratio and high hardness. These steels are prone to hydrogen induced cracking （HIC） and softening in the heat affected zone （HAZ） after welding. The use of austenitic stainless steel （ASS） consumables to weld the above steel was the only available remedy to avoid HIC because of higher solubility for hydrogen in austenitic phase. Recent studies revealed that low hydrogen ferritic （LHf） steel consumables can also be used to weld Q＆T steels, which can give very low hydrogen levels in the weld deposits and required resistance against cold cracking. Hence, in this investigation an attempt has been made to study the performance of armour grade Q＆T steel joints fabricated by flux cored arc welding with LHf steel consumables. Two different consumables namely （i） austenitic stainless steel and （ii） low hydrogen ferritic steel have been used to fabricate the joints by flux cored arc welding （fCAW） process. The joints fabricated by LHf consumable exhibited superior transverse tensile properties due to the presence of ferrite microstructure in weld metal. The joints fabricated by ASS consumable showed higher impact toughness due to the presence of austenitic phase in weld metal microstructure. The HAZ softening in coarse grain heat affected zone （CGHAZ） is less in the joints fabricated using LHf consumable due to the lower heat input involved during fabrication compared to the joints fabricated using ASS consumables.

关键词： Quenched and tempered steel flux cored arc welding process Low hydrogen ferritic steel Tensile properties

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

GLOBAL EXISTENCE fOR A PARTICULAR INHOMOGENEOUSCONVECTION DIffUSION SYSTEM

引用

Acta Mathematica Scientia 1995年第4期15卷 406-414页

作者：朱长江赵会江 ACAD SINICA YOUNG SCIENTIST LAB MATH PHYSWUHAN INST MATH SCIWUHAN 430071PEOPLES R CHINA

This paper considers the Cauchy problem of the following convection diffusion system [GRAPHICS] with initial data [GRAPHICS] A global existence result is established by employing the techniques of f. B. Weissler and t... 详细信息

关键词： inhomogeneous convection diffusion system global solution energy method

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

Primary cilia as a novel horizon between neuron and environment

引用

Neural Regeneration Research 2017年第8期12卷 1225-1230页

作者： Gregory W.Kirschen Qiaojie Xiong Medical scientist Training Program Stony Brook University Stony Brook NY USA Department of Neurobiology & Behavior Stony Brook University Stony Brook NY USA

The primary cilium, a hair-like sensory organelle found on most mammalian cells, has gained recent attention within the field of neuroscience. Although neural primary cilia have been known to play a role in embryonic central nervous system patterning, we are just beginning to appreciate their importance in the mature organism. After several decades of investigation and controversy, the neural primary cilium is emerging as an important regulator of neuroplasticity in the healthy adult central nervous system. further, primary cilia have recently been implicated in disease states such as cancer and epilepsy. Intriguingly, while primary cilia are expressed throughout the central nervous system, their structure, receptors, and signaling pathways vary by anatomical region and neural cell type. These differences likely bear relevance to both their homeostatic and neuropathological functions, although much remains to be uncovered. In this review, we provide a brief historical overview of neural primary cilia and highlight several key advances in the field over the past few decades. We then set forth a proposed research agenda to fill in the gaps in our knowledge regarding how the primary cilium functions and malfunctions in nervous tissue, with the ultimate goal of targeting this sensory structure for neural repair following injury.

关键词： G protein-coupled receptor sonic hedgehog seizure stroke stem cell neurogenesis plasticity

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

Genetic targeting of astrocytes to combat neurodegenerative disease

引用

Neural Regeneration Research 2020年第2期15卷 199-211页

作者： Rachel Kéry Allen P. f. Chen Gregory W. Kirschen Medical scientist Training Program MSTP)Stony Brook MedicineStony BrookNYUSA Department of Neurobiology & Behavior Stony Brook UniversityStony BrookNYUSA

Astrocytes, glial cells that interact extensively with neurons and other support cells throughout the central nervous system, have recently come under the spotlight for their potential contribution to, or potential regenerative role in a host of neurodegenerative disorders. It is becoming increasingly clear that astrocytes, in concert with microglial cells, activate intrinsic immunological pathways in the setting of neurodegenerative injury, although the direct and indirect consequences of such activation are still largely unknown. We review the current literature on the astrocyte’s role in several neurodegenerative diseases, as well as highlighting recent advances in genetic manipulation of astrocytes that may prove critical to modulating their response to neurological injury, potentially combatting neurodegenerative damage.

关键词： Alzheimer's disease amyotrophic lateral sclerosis glia immune system inflammation Parkinson's disease reactive astrocyte regeneration

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

Lifetime-tunable circularly polarized luminescent system based on triplet-to-singlet förster resonance energy transfer

引用

Science China Chemistry 2024年第9期67卷 2918-2922页

作者： Zhenyi He Zizhao Huang Xiang Ma Key Laboratory for Advanced Materials and feringa Nobel Prize scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Circularly polarized luminescence(CPL)materials have received widespread attention due to their remarkable performance and broad ***,current CPL material research primarily focuses on tunable color,intensity,and *** CPL with adjustable lifetime remains a significant ***,a series of CPL polymeric materials with tunable lifetime were obtained by employing phosphorescent terephthalic acid and chiral organic small molecule R/S-BNAf(a luminescent binaphthol derivative)to copolymerize with acrylamide in different *** was verified that this performance results from the different energy transfer efficiency between luminophores with varying ratios of the monomers for *** strategy to realize CPL with tunable lifetime by modulating the energy transfer efficiency will provide a new perspective to broaden the applications of CPL materials.

关键词： circularly polarized luminescence tunable lifetime förster resonance energy transfer room temperature phosphorescence

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

Predicting global landslide spatiotemporal distribution:Integrating landslide susceptibility zoning techniques and real-time satellite rainfall estimates

引用

International Journal of Sediment Research 2008年第3期23卷 249-257页

作者： Robert f. ADLER Senior Research scientist Code 613.1 Laboratory for Atmospheres NASA/Goddard Space Flight Center Greenbelt MD 20771 U. S. ADr.

Landslides triggered by rainfall can possibly be foreseen in real time by jointly using rainfall intensity-duration thresholds and information related to land surface susceptibility. However, no system exists at either a national or a global scale to monitor or detect rainfall conditions that may trigger landslides due to the lack of sufficient ground-based observing network in many parts of the world. Recent advances in satellite remote sensing technology and increasing availability of high-resolution geospatial products around the globe have provided an unprecedented opportunity for such a study. In this paper, a framework for developing a preliminary real-time prediction system to identify where rainfall-triggered landslides will occur is proposed by combining two necessary components: surface landslide susceptibility and a real-time space-based rainfall analysis system (http://***). first, a global landslide susceptibility map is derived from a combination of semi-static global surface characteristics (digital elevation topography, slope, soil types, soil texture, land cover classification, etc.) using a GIS weighted linear combination approach. Second, an adjusted empirical relationship between rainfall intensity-duration and landslide occurrence is used to assess landslide hazards at areas with high susceptibility. A major outcome of this work is the availability for the first time of a global assessment of landslide hazards, which is only possible because of the utilization of global satellite remote sensing products. This preliminary system can be updated continuously using the new satellite remote sensing products. This proposed system, if pursued through wide interdisciplinary efforts as recommended herein, bears the promise to grow many local landslide hazard analyses into a global decision-making support system for landslide disaster preparedness and mitigation activities across the world.

关键词： Landslide Natural disasters Satellite remote sensing Real-time precipitation analysis Landslide susceptibility

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

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：