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Secure enclave安全体系技术分析与研究

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信息技术与网络安全 2018年第1期37卷 30-32,51页

作者：廖正赟郭建胜郑州信大捷安移动信息安全工程实验室河南郑州450004 信息工程大学河南郑州450004

在移动互联网时代,移动智能终端已经成为人们随身携带、随时使用的重要设备。应对移动应用环境中面临的安全威胁,成为业界面临的重要问题。Apple公司设计了一套安全体系,依靠Secure enclave模块来实现密码运算和敏感数据的存储,在实际... 详细信息

在移动互联网时代,移动智能终端已经成为人们随身携带、随时使用的重要设备。应对移动应用环境中面临的安全威胁,成为业界面临的重要问题。Apple公司设计了一套安全体系,依靠Secure enclave模块来实现密码运算和敏感数据的存储,在实际的应用中取得了很好的效果。从硬件、系统和通信机制方面分析了Secure enclave模块的组成结构,进而对系统进行了安全性分析,最后,对模块进行了总结和展望。

关键词： Secure enclave 安全隔离可信计算环境 L4

Peraluminous A-type granites formed through synchronous fractionation,magma mixing,mingling,and undercooling:evidence from microgranular enclaves and host Mesoproterozoic Kanigiri granite pluton,Nellore Schist Belt,southeast India

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Acta Geochimica 2023年第4期42卷 603-636页

作者： Ch.Narshimha Santosh Kumar Department of Geology Centre of Advanced StudyKumaun UniversityNainital 263001India

The field and microstructural features coupled with mineral chemical data from microgranular enclave(ME)and host Mesoproterozoic Kanigiri granite(KG)pluton of Nellore Schist Belt(NSB),Southeastern India,have been documented in order to infer the likely processes responsible for the origin and evolution of ME and host KG *** ME and host KG bear the same mineral assemblages barring the KG which does not contain amphibole;however,they are modally *** ME in KG is originated due to multiple intrusions of ME magmas into the crystallizing host KG magma *** and textural features indicate the dynamic magma flow,mingling,and undercooling of the ME against a relatively cooler surface of host KG *** presence of NSB country rock xenoliths and its diffuse boundaries suggest the intrusive relation and marginal assimilation by the intruding KG *** occasional cumulate texture in the ME appears to have formed by the accumulation of early-formed minerals that crystallized rapidly in the ME magma *** ME shows the magmatically deform features developed due to the flowage and erosion by the subsequent intrusions of ME magma pulses into the crystallizing host KG magma *** ME amphiboles show unusual composition as ferro-edenitic hornblende to potassian-hastingsitic hornblende,that crystallized in the subalkaline-alkaline transition,low fO_(2)(reducing to mildly oxidizing)*** unusual extremely low Mg/Mg+Fe^(t)=0.015(avg.)of ME amphiboles may be related to the changing physico-chemical(P,T,fO_(2),and H_(2)O)condition of the ME magma or they might have crystallized in equilibrium with more evolved KG *** KG(FeOt/MgO=37.04,avg.)and ME(FeO~t/MgO=77.72,avg.)biotites are siderophyllite,and buffered between QFM and NNO syn-crystallizing in the water undersaturated(H_(2O)≈3.58 wt.%in KG;≈3.53wt.%in ME),alkaline anorogenic(A-type)host magmas that were emplaced at mid-crustal(4–5 kbar;17 km)***,microtextural and mineral

关键词： enclave Kanigiri granite Magma mixing-fractionation Nellore schist belt SE India

Discovery of enclaves from Cenozoic PuluVolcanic Rocks in West Kunlun Mountains and ItsGeological Implications

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Journal of China University of Geosciences 2002年第1期13卷 30-34页

作者： Zhang Zhaochong Xiao Xuchang Wang Jun Wang YongInstitute of Geology , Chinese Academy of Geological Sciences, Beijing 100037 Institute of Geology Chinese Academy of Geological Sciences Beijing 100037

In this paper, we present the occurrence and mineral components of the enclaves firstly discovered in the Cenozoic Pulu volcanic rocks in west Kunlun Mountains, and propose that the enclave is accumulated by fractional crystallization within high-level magma chamber. In addition, the chemical compositions of its primary magma are calculated. The calculated compositions are similar to those of the Kangxiwa volcanic rocks that belong to the same volcanic belt in the Pulu volcanic region, suggesting their origin from the same source region. However, the temperatures and oxygen fugacity of magmas at high-level magma chamber decreased along with fractional crystallization.

关键词： enclave fractional crystallization volcanic rocks West Kunlun Mountains.

Recognizing Brazilian Cerrado enclaves by Modeling Geoenvironmental Parameters

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Journal of Geographic Information System 2020年第2期12卷 125-140页

作者： Marcus Vinicius de Melo Oliveira Antonio Manoel dos Santos Oliveira Augusto Francener Nogueira Gonzaga Paulo Eduardo de Oliveira Anderson Targino da Silva Ferreira Master Program in Geoenvironmental Analysis of the Guarulhos University (MAG-UNG) Guarulhos São Paulo Brazil Faculdade de Goiana (FAG) Goiana Pernambuco Brazil Geosciences Institute of the University of São Paulo (IGc-USP) Cidade Universitária São Paulo Brazil

This work focused on the prediction modeling of Cerrado occurrences in the Atlantic Rainforest predominance in the São Paulo Metropolitan Region (SPMR), the fourth largest urban area, in the city of Guarulhos, southeastern Brazil. The methodology was based on the selection of records of occurrence of Cerrado in georeferenced databases, thematic maps of geoenvironmental layers, and modeling of the distribution of species through the MaxEnt tool. Besides that, field research confirmed the presence or not of the species in the areas with a high probability of occurrence of Cerrado (≥0.7). As a result, the model observed a great capacity for the prediction of the occurrence of Cerrado in Ecotonal and anthropic regions (AUC = 0.82), revealing important hotspots such as relics from the past or Cerrado enclaves of high biodiversity. The work also points priority areas for the conservation and preservation of this increasingly endangered biome.

关键词： Cerrado enclave Hotspots Remaining Geoenvironmental Parameters Prediction of Adequacy MaxEnt

Guangtoushan granites and their enclaves:Implications for Triassic mantle upwelling in the northern margin of the North China Craton

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Guangtoushan granites and their enclaves:Implications for Tr...

Crust-mantle interaction beneath the Luxi Block,eastern North China Craton:Evidence from coexisting mantle-and crust-derived enclaves in a quartz monzonite pluton

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Zhou Zhang Hongfu Zhang Ji'an Shao Jifeng Ying Yueheng Yang M.Santosh State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Division of Interdisciplinary Sciences Faculty of ScienceKochi UniversityKochi 780-8520Japan

Mineral electron microprobe,bulk rock major,trace elements and Nd isotopes,and zircon U-Pb and Hf isotopic data are reported for granites and dioritic enclaves from the Guangtoushan granitic complex in the northern margin of the North China *** zircon U-Pb dating identifies two stages of *** early stage enclave and host granite have identical ages(250±2 Ma) and similar bulk rock Nd isotopes(εNd(t) =-11.5 to -12.2) as well as similar zircon Hf isotopes(εHf(t) = -13.3 to -17.4).However,although the late stage enclave(206±2 Ma),host granite(208±1 Ma) and leucogranite(207±3 Ma) display comparable ages,but exhibit distinct isotopic features:the granite displays moderate bulk rock Nd isotopic value(εNd(t) =-8.3) and zirconεHf(t) from -2.6 to -10.4;the enclave shows least negative bulk rock eNd(t) of—3.9 and zirconεHf(t) from 0 to—5.4;and the leucogranite possesses more pronounced negative bulk rock Nd(εNd(t) =—17.2) and zircon Hf isotopic compositions(εHf(t) =—6.2 to—19.0).An integration of field observations,geochronology, geochemistry and zircon Hf isotopic data points to a complex petrogenetic history,where the early stage enclave-granite pair is a product of the early crystallization of felsic magmas that evolved from a mafic magma,whereas the late stage enclave and granite were derived by magma *** late stage leucogranite is considered as a product of remelting of Phanerozoic igneous rocks within this *** Guangtoushan granitic complex offers robust evidence for a gradual mantle upwelling during Triassic in the northern margin of the North China Craton.

关键词： Guangtoushan Zircon Geochronology Granite enclave North China Craton

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Crust-mantle interaction beneath the Luxi Block,eastern Nort...

Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： Ting-Guang Lan Hong-Rui Fan M.Santosh Fang-Fang Hu Kui-Feng Yang Yue-Heng Yang Yongsheng Liu Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences School of Earth Sciences and Resources China University of Geosciences Beijing State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan

The Laiwu quartz monzonite in the Luxi Block of eastern North China Craton(NCC)is characterized by the presence of abundant plagioclase amphibolite and gabbro-diorite *** we present LA-ICPMS zircon U-Pb ages which show that the host quartz monzonite was emplaced at 129,8±1.0 Ma,whereas the protolith of the plagioclase amphibolite enclaves formed during early Paleoproterozoic The gabbro-diorite enclaves were produced simultaneously with or slightly earlier than the formation of the host quartz monzonite,Combined with the Archean and Paleoproterozoic zircons as well as the low tNd(0)values(-18.4 to-18.0)in the plagioclase amphibolite enclaves, the equilibrium temperature and pressure conditions(645-670 0C and 4.8-6.5 Kb)suggest that the plagioclase amphibolite enclaves are fragments of the middle *** gabbro-diorite enclaves mainly originated from an enriched lithospheric mantle metasomatized by melts/fluids derived from the continental oust,as indicated by their low SiO2(54.4-54.7 wt.%)and high MgO(10.9-11.1 wt.%)contents as well as the negative ENd(t)values(-13.5 to -10.7)and enrichment of LILEs(e.g,Ba and Sr)and depletion of HFSEs(e.g.,Nb,Ta,P and Ti).Compared with the ancient crustal rocks and the mafic plutons considered to have been derived from lithospheric mantle in the Lux Block,the moderate ENd(t)(-15.7 to-15.1)and q(t)(-20.7 to-13.0)values of the quartz monzonite in our study suggest that both mantle-and crust-derived melts were involved in the magma *** we propose a model involving magma mixing between mantle-and crust-derived melts for the formation of the quartz monzonite. Since significant crust-mantle interaction is recorded not only in the quartz monzonite and its enclaves in the Luxi Block but also in the other granitoids widespread in the NCC,it is considered that large-scale crust-mantle interaction and magmatic underplating were associated with the Mesozoic lithospheric mantle thinning and crustal reactivation in the eas

关键词： Quartz monzonite enclave Crustal reactivation Crust-mantle interaction North China Craton

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 657-678页

作者： Kazem KAZEMI Soroush MODABBERI Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN School of Geology College of ScienceUniversity of TehranTehranIran Research Centre for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Department of Geochemistry and Environmental Sciences School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of Earth and Sciences Faculty of SciencesUniversity of KurdistanSanandajIran Department of Science Education Farhangian UniversityTehranIran

The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were *** is suggested that the rocks are metaluminous(A/CNK=1.32-1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical *** host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for *** have relatively low SiO_(2) contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived ***-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492-0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2)of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2)=729 Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid *** T_(DM1)(Nd)and T_(DM2)(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian *** composition indicates a crystallization temperature of~1000℃ and a depth of~9 km.

关键词： enclave magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc

The Genesis of the Damiao Granodiorite in Siziwangqi and Its Constraint on the Crust Evolution of Inner Mongolia

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地学前缘 2009年第S1期16卷 213-214页

作者： Yongmei Zhang,Huafeng Zhang,Weiping Zhu,Wencan Liu,Zhiguang Zhou 1.China University of Geosciences(Beijing),Beijing 100083,China. 2.China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China

A large number of granitoids constitutes a giant granitic belt trending EW in the Inner *** a representative of those intrusions,the Damiao granitoid in Siziwangqi area may serve as a natural laboratory for the study ... 详细信息

关键词： mafic microgranular enclave granodiorite magma mixing Siziwangqi Inner Mongolia

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SGX技术的分析和研究

软件学报 2018年第9期29卷 2778-2798页

作者：王鹃樊成阳程越强赵波韦韬严飞张焕国马婧武汉大学国家网络安全学院湖北武汉430072 空天信息安全与可信计算教育部重点实验室湖北武汉430072 Baidu Information Technology Co. LtdBordeaux DrSunnyvaleCA 94089USA 信息保障技术重点实验室北京100072

安全性是云计算中一项极为重要的需求,然而如何保护云计算中关键应用程序和数据的安全、防止云平台管理员泄露用户隐私,仍然是目前没有解决的难题.2013年,Intel公司提出了新的处理器安全技术SGX,能够在计算平台上提供一个可信的隔离空间... 详细信息

安全性是云计算中一项极为重要的需求,然而如何保护云计算中关键应用程序和数据的安全、防止云平台管理员泄露用户隐私,仍然是目前没有解决的难题.2013年,Intel公司提出了新的处理器安全技术SGX,能够在计算平台上提供一个可信的隔离空间,保障用户关键代码和数据的机密性和完整性.作为系统安全领域的重大研究进展,SGX对系统安全,尤其是云计算安全保护方面具有非常重要的意义.该文介绍了SGX的原理和特性,分析了SGX的关键技术以及针对SGX的侧信道攻击及防御方法.同时,总结和归纳了该技术的研究成果,分析了SGX技术与其他可信计算技术的异同,并指出了SGX技术的未来研究挑战和应用需求.

关键词：云计算 SGX enclave 可信计算侧信道云安全