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Geochemistry and spatial distribution of OIB and MORB in A’nyemaqen ophiolite zone: Evidence of Majixue-shan ancient ridge-centered hotspot

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Science China Earth Sciences 2007年第2期50卷 197-208页

作者： GUO AnLin ZHANG GuoWei SUN YanGui ZHENG JianKang LIU Ye WANG JianQi National Key Lab of Continental Dynamics Northwest UniversityXi’an 710069China Qinghai Institute of Geological Survey Xining 810012China

The mafic volcanic association is made up of OIB, E-MORB and N-MORB in the A'nyemaqen Paleozoic ophiolites. Compared with the same type rocks in the world, the mafic rocks generally display lower Nb/U and Ce/Pb ratios and some have Nb depletion and Pb enrichment. The OIB are LREE-enriched with (La/Yb)N =5―20, N-MORB are LREE-depleted with (La/Yb)N = 0.41―0.5. The OIB are featured by incompatible element enrichment and the N-MORB are obviously depleted with some metasomatic ef- fect, and E-MORB are geochemically intermediated. These rocks are distributed around the Majixue- shan OIB and gabbros in a thickness greater than a thousand meters and transitionally change along the ophiolite extension in a west-east direction, showing a symmetric distribution pattern as centered by the Majixueshan OIB, that is, from N-MORB, OIB and E-MORB association in the Dur'ngoi area to OIB in the Majixueshan area and then to N-MORB, OIB and E-MORB assemblage again in the Buqing- shan area. By consideration of the rock association, the rock spatial distribution and the thickness of the mafic rocks in the Majixueshan, coupled with the metasomatic relationship between the OIB and MORB sources, it can be argued that the Majixueshan probably corresponds to an ancient hotspot or an ocean island formed by mantle plume on the A'nyemaqeh ocean ridge, that is the ridge-centered hotspot, tectonically similar to the present-day Iceland hotspot.

关键词： A’nyemaqen ophiolite zone OIB N-MORB and E-MORB association spatial distribution Majixueshan ridge-centered hotspot me- tasomatism mantle plume

Optimizing B^(+)-tree for hybrid memory with in-node hotspot cache and eADR awareness

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Frontiers of Computer Science 2024年第5期18卷 133-145页

作者： Peiquan JIN Zhaole CHU Gaocong LIU Yongping LUO Shouhong WAN School of Computer Science and Technology University of Science and Technology of ChinaHefei 230027China

he advance in Non-Volatile Memory(NVM)has changed the traditional *** to DRAM,NVM has the advantages of nonvolatility and large ***,as the read/write speed of NVM is still lower than that of DRAM,building DRAM/NVM-based hybrid memory systems is a feasible way of adding NVM into the current computer *** paper aims to optimize the well-known B^(+)-tree for hybrid *** novelty of this study is ***,we observed that the space utilization of internal nodes in B^(+)-tree is generally below 70%.Inspired by this observation,we propose to maintain hot keys in the free space within internal nodes,yielding a new index named HATree(Hotness-Aware Tree).The new idea of HATree is to use the unused space of the parent of leaf nodes(PLNs)as the hotspot data ***,no extra space is needed,and the in-node hotspot cache can efficiently improve query ***,to further improve the update performance of HATree,we propose to utilize the eADR technology supported by the third-generation Intel Xeon Scalable Processors to enhance HATree with instant log persistence,which results in the new HATree-Log *** conduct extensive experiments on real hybrid memory architecture involving DRAM and Intel Optane Persistent Memory to evaluate the performance of HATree and *** state-of-the-art indices for hybrid memory,namely NBTree,LBTree,and FPTree,are included in the experiments,and the results suggest the efficiency of HATree and HATree-Log.

关键词： hybrid memory B^(+)-tree hotspot in-node cache eADR

Recovery of threatened plant species and their habitats in the biodiversity hotspot of the Southwest Australian Floristic Region

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Plant Diversity 2019年第2期41卷 59-74页

作者： Leonie Monks Sarah Barrett Brett Beecham Margaret Byrne Alanna Chant David Coates J.Anne Cochrane Andrew Crawford Rebecca Dillon Colin Yates Biodiversity and Conservation Science Department of Biodiversity Conservation and Attractions Parks and Wildlife Service Department of Biodiversity Conservation and Attractions

The Southwest Australian Floristic Region(SWAFR) is a global biodiversity hotspot with high plant diversity and endemism and a broad range of threatening processes. An outcome of this is a high proportion of rare and threatened plant species. Ongoing discovery and taxonomic description of new species, many of which are rare, increases the challenges for recovery of threatened species and prioritisation of conservation actions. Current conservation of this diverse flora is based on integrated and scientific evidence-based management. Here we present an overview of current approaches to the conservation of threatened flora in the SWAFR with a focus on active management through recovery and restoration that is integrated with targeted research. Key threats include disease, fragmentation, invasive weeds, altered fire regimes, grazing, altered hydro-ecology and climate change. We highlight the integrated approach to management of threats and recovery of species with four case studies of threatened flora recovery projects that illustrate the breadth of interventions ranging from In situ management to conservation reintroductions and restoration of threatened species habitats. Our review and case studies emphasise that despite the scale of the challenge, a scientific understanding of threats and their impacts enables effective conservation actions to arrest decline and enhance recovery of threatened species and habitats.

关键词： Threatened species Threatening processes Conservation Recovery Restoration Biodiversity hotspot

A preliminary study on numerical simulation of microwave heating process for chemical reaction and discussion of hotspot and thermal runaway phenomenon

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Science China(Physics,Mechanics & Astronomy) 2009年第4期52卷 551-562页

作者： ZHAO Xiang HUANG KaMa YAN LiPing YAO Yuan College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Chengdu University of Information Technology Chengdu 610041China

The nonlinear process of microwave heating chemical reaction is studied by means of numerical simulation. Especially,the variation of temperature in terms of space and time,as well as the hotspot and thermal runaway phenomena are discussed. Suppose the heated object is a cylinder and the incident electromagnetic(EM) wave is plane wave,the problem turns out to be a coupling calculation of 2D multi-physical fields. The integral equation of EM field is solved using the method of moment(MoM) and the thermal conduction equation is solved using a semi-analysis method. Moreover,a method to determine the equivalent complex permittivity of reactant under the heating is presented in order to perform the calculation. The numerical results for water and a dummy chemical reaction(A) show that the hotspot is a ubiquitous phenomenon in microwave heating process. When the radius of the heated object is small,the highest temperature occurs somewhere inside the object due to the concentration of the EM wave. While the radius increases to a certain degree,the highest temperature occurs somewhere close to the surface due to the skin effect,and the whole high temperature area shows crescent-shaped. That is in accordance with basic physical principles. If the radius is kept the same in the heating process,the hotspot position of water does not change,while that of reaction A with several radius values varies. For either water or A,the thermal runaway phenomenon in which small difference of radius results in large difference of highest temperature,occurs easily when the radius is small. On the contrary,it is not evident when the radius is large. Moreover,it is notable that the highest temperature in water shows oscillating decreasing trend with the increase of radius,but in reaction A almost decreases monotonously. Further study should be performed to determine if this difference is only an occasional occurrence.

关键词： numerical simulation microwave heating chemical reaction hotspot phenomenon thermal runaway

hotspot Detection of Semiconductor Lithography Circuits Based on Convolutional Neural Network

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Journal of Microelectronic Manufacturing 2018年第2期1卷 31-38页

作者： Xingyu Zhou Youling Yu Tongji University ShanghaiChina201804

In the advanced semiconductor lithography manufacturing process,the sub-wavelength lithography gap may cause lithographic error and the difference between the wafer pattern and mask pattern which may cause wafer defects in the later *** if a layout passes the design rule checking(DRC),it still might contain process hotspots which are sensitive to the lithographic ***,process-hotspot detection has become a crucial *** this paper,we propose a convolutional neural network(CNN)based process-hotspot detection *** network parameters including the training batch size,learning rate,loss functions as well as the optimization methods are compared and the optimal method is proposed with respect to a typical *** results of the tuned model are better than common machine learning methods.A general training flow is *** method is flexible and can be applied to different benchmarks for better hotspot detection performance.

关键词： lithography hotspot detection CNN deep learning

Efficient algorithm for improving the hotspot effect of the operational MODIS BRDF product

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遥感学报 2014年第4期18卷 804-825页

作者： DONG Yadong JIAO Ziti ZHANG Hu Li Jiayue JIAO Guangping SHI Hanyu School of Geography Beijing Normal University Beijing 100875 China State Key Laboratory of Remote Sensing Science Beijing 100875 China Key Laboratory of Environmental Remote Sensing and Digital City Beijing 100875 China

An algorithm for modeling bidirectional reflectance anisotropies of land surfaces has been developed as a surrogate for the operational MODIS Bidirectional Reflectance Distribution Function （BRDF） and albedo product for user community. This algorithm is a set of kernel-driven BRDF models extensively used in several space-borne remotely sensed BRDF/albedo products. Among these models, RossThick （RT）-LiSparseR （RTLSR） has been selected as the current operational MODIS BRDF/albedo algorithm. However, the hotspot effect has not been considered in RT kernel. As such, the use of an RTLSR model underestimates hotspot reflectance, thereby influencing the accuracy of the retrieval of vegetation structures, such as clumping index. On the basis of Breon＇s hotspot factor, Maignan corrected RT kernel to generate a RTMalgnan （RTM） kernel. For producers, a 13-year MODIS BRDF/albedo product is reprocessed using this corrected model, but this task is time consuming. For users, the direct use of this corrected model for MODIS observations is complicated because the equivalent inputs of the operational RTLSR algorithm are not easily available. In this study, a method was developed to correct the hotspot effect for the operational MODIS BRDF product, which is available for users. Based on the effective vaFldation using POLDER-3/BRDF data and the selected MODIS data, this study shows that （1） an improvement of approximately 10.12% of relative error between our method and the RTLSR model can be obtained by estimating the hotspot reflectance; （2） a relative error of approximately 2.10% occurs between this method and the RTM-LiSparseR （RTMLSR） model, but this difference is not significant; （3） relative error reaches approximately 4.99% between this method and the RTLSR model to simulate NDFID but decreases to approximately 1.32% between this method and the RTMLSR model.

关键词： kernel-driven BRDF models AMBRALS BRDF hotspot MODIS BRDF/albedo product

A Multiscale Assessment of the Risks Imposed by Plantation Forestry on Plant Biodiversity in the hotspot Central Chile

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Open Journal of Ecology 2014年第16期4卷 1025-1044页

作者： Andreas Ch. Braun Joachim Vogt Chair of Remote Sensing and Landscape Information Systems (FeLis) University of Freiburg Freiburg im Breisgau Germany Institute of Regional Science (IfR) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany

We assessed the effects of plantations of exotic trees (Pinus radiata, Eucalyptus globulus, and Populus nigra) on plant biodiversity in the temperate zone of the biodiversity hotspot of Central Chile. This region has suffered from intense deforestation in favor of plantation establishment in the major part of the coastal area since the neoliberal turn in 1973. The approach presented aimed to analyze plant biodiversity on the α-, β- and γ-scale. Furthermore, a plantation evaluation index was applied in order to provide quantitative figures on management practices. Species richness is reduced by 50% below plantations. Diversity and evenness index values are also significantly reduced. Analyses on β-similarity indicate that plantations do not host species absent in adjacent native forests, and no additional habitat heterogeneity is gained. On the γ-scale, plantations lower the number of total species observed;especially of endemic species. The abundance of species considered as invasive is significantly higher and frequently, invasive plants dominate the understory. The evaluation index attests rather poor plantation management in Central Chile since plantations are grown as monocultures, natural elements and native species are lacking at specific sites and plantations are insufficiently connected to native plant formations at the landscape scale. Results give much concern since deforestation processes as observed in our study area is about to begin in Patagonia as well. If management practices from the temperate zone are adopted in Patagonia, a considerable decline in plant biodiversity has to be expected there.

关键词： Biodiversity Decline Plantations Biodiversity hotspot Pinus radiate Eucalyptus globules Chile

嵌入式Java虚拟机CLDC hotspot实现分析、移植及优化

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嵌入式Java虚拟机CLDC HotSpot实现分析、移植及优化

作者：张金福电子科技大学

学位级别：硕士

CLDC(面向连接受限的设备配置)是Sun公司为资源受限、连接受限的嵌入式设备制定的一个Java应用开发规范,目前已广泛应用在移动电话、PDA、数字电视机顶盒等嵌入式设备中,CLDC实现的核心是Java虚拟机,除了满足嵌入式设备的特性以外,符合J... 详细信息

CLDC(面向连接受限的设备配置)是Sun公司为资源受限、连接受限的嵌入式设备制定的一个Java应用开发规范,目前已广泛应用在移动电话、PDA、数字电视机顶盒等嵌入式设备中,CLDC实现的核心是Java虚拟机,除了满足嵌入式设备的特性以外,符合Java虚拟机规范。CLDC hotspot实现是Sun公司为嵌入式设备开发的高性能Java虚拟机,是一个符合Java虚拟机规范的纯32位虚拟机。CLDC hotspot实现的应用目标是系统资源受限设备,采用了Sun公司新的虚拟机技术,提高了Java应用程序的运行效率。第一代嵌入式Java虚拟机KVM是通过字节码解释器执行Java应用程序的传统虚拟机,KVM的设计重点是虚拟机的可移植性和平台无关性,和KVM相比,虚拟机CLDC hotspot实现在系统资源受限设备上运行能获得更高的性能。嵌入式Java虚拟机CLDC hotspot实现在嵌入式设备上运行需要嵌入式操作系统的支持,嵌入式可配置操作系统eCos是一个由GNU开源开发工具支持的开源实时操作系统,eCos支持当前流行的大部分嵌入式处理器,具有很好的可移植性,利用配置工具可实现eCos的源代码级配置,目前,eCos已经在国内外很多商业开发项目或个人项目得到广泛应用。eCos能满足资源受限的嵌入式系统的需求,同时,eCos对TCP/IP等网络协议的支持,使得eCos在网络应用方面具有良好的支持能力和稳健性,突出的网络支持功能满足了嵌入式终端设备对于网络通信能力的要求。本论文的主要内容是研究嵌入式Java虚拟机CLDC hotspot实现机制以及在eCos系统上的移植和优化实现。论文首先阐述了Java虚拟机体系结构,重点研究了嵌入式Java虚拟机CLDC hotspot的实现机制,实现了基于eCos平台的CLDC hotspot移植接口,并对移植过程中应注意的问题作了详细论述,论文最后针对应用需求和平台环境对虚拟机字节码解释器做了优化设计和实现。

关键词： Java虚拟机 CLDC hotspot 自适应编译器 eCos

Seismic Imaging of the Upper Mantle under the Erebus hotspot in Antarctica

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地学前缘 2009年第S1期16卷 205-205页

作者： Sandeep Gupta S.S.Rai National Geophysical Research Institute(CSIR)

P-wave velocity images are determined under the Mount Erebus hotspot,Antarctica by using teleseismic *** results show a prominent low-velocity(low-v)anomaly of nearly circular symmetry(about 250-300 km in diameter)to about 200 km depth under the Mount Erebus volcanic region,which further extends down to～400 km as a narrow tilted *** observed low-v anomaly beneath the Mount Erebus volcano can be an expression of a thermal anomaly of deep origin.

关键词： Mount Erebus Antarctica hotspot teleseismic tomography