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Impact of one satellite outage on ARAIM depleted constellation configurations

Chinese Journal of Aeronautics 2019年第4期32卷 967-977页

作者： Qian MENG Jianye LIU Qinghua ZENG Shaojun FENG Rui XU Navigation Research Center Nanjing University of Aeronautics and Astronautics Centre for Transport Studies Imperial College London

Advanced Receiver Autonomous Integrity Monitoring(ARAIM) is a new technology that will provide worldwide coverage of vertical guidance in aviation navigation. The ARAIM performance and improvement under depleted constellations is a practical problem that needs to be faced and researched further. It is a shortcut that improves the availability in position domain whose key idea is to replace the conventional least squares process with a non-least-squares estimator to lower the integrity risk in exchange for a slight increase in nominal position error. The contributions given in this paper include two parts: First, the impacts of one satellite outage on different constellations are analyzed and compared. The conclusion is that GPS is more sensitive and vulnerable to one satellite outage. Second, a constellation weighted ARAIM(CW-ARAIM)position estimator is proposed. The position solution is replaced by a constellation weighted average solution to eliminate the constellation difference. The new solution will move close to the constellation solutions with respect to the accuracy requirement. The simulation results under baseline GPS and Galileo dual-constellation show that the one GPS satellite outage will knock the availability from 91% to only 50%. The performance remains stable with one Galileo satellite outage. With the assistance of the CW-ARAIM method, the availability can increase from 50% to more than80% under depleted GPS configurations. Even without any satellite outage, the proposed method can effectively improve the availability from 91.29% to 98.75%. The test results under optimistic constellations further verify that a balanced constellation is more important than more satellites on orbit and the superiority of CW-ARAIM method is still effective.

关键词： Advanced receiver autonomous integrity monitoring depleted constellation One satellite outage Position estimator Weighted solution

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Analysis of single-event transient sensitivity in fully depleted silicon-on-insulator MOSFETs

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Nuclear Science and Techniques 2018年第4期29卷 108-113页

作者： Jing-Yan Xu Shu-Ming Chen Rui-Qiang Song Zhen-Yu Wu Jian-Jun Chen College of Computer National University of Defense Technology National Laboratory for Parallel and Distributed Processing National University of Defense Technology

Based on 3 D-TCAD simulations, single-event transient(SET) effects and charge collection mechanisms in fully depleted silicon-on-insulator(FDSOI) transistors are investigated. This work presents a comparison between28-nm technology and 0.2-lm technology to analyze the impact of strike location on SET sensitivity in FDSOI devices. Simulation results show that the most SET-sensitive region in FDSOI transistors is the drain region near the gate. An in-depth analysis shows that the bipolar amplification effect in FDSOI devices is dependent on the strike locations. In addition, when the drain contact is moved toward the drain direction, the most sensitive region drifts toward the drain and collects more charge. This provides theoretical guidance for SET hardening.

关键词： Single-event transient Charge collection Bipolar amplification Fully depleted silicon-on-insulator

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Late Carboniferous Vertical Crustal Growth in Northern North China Craton: Evidence from Zircon U-Pb Age and depleted Hf Isotope of the Dongwanzi Syenite

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 206-207页

作者： MA Xu CHEN Bin CHEN Jiafu Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Department of GeologyNortheastern UniversityShenyang 110004China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China

Objective Though the Central Asian Orogenic Belt (CAOB) is characterized by widespread Phanerozoic crustal growth,there is little juvenile crust documented in its southeastern segment,northern margin of the North China Craton(NCC)(Zhang et al,2007,2009).Late Carboniferous Dongwanzi ultramafic-mafic cumulate complex occurs in northern margin of the NCC and is intruded by a syenite with depleted Sr-Nd isotopes (Ma et al.,2014).However,the age and petrogenesis of this syenite is poorly constrained.In this study,we present new petrological,zircon U-Pb and Hf isotopic data of the Dongwanzi syenite,in order to put insights on its formation age and petrogenetic relationship with cumulates.

关键词： Evidence from Zircon U-Pb Age and depleted Hf Isotope of the Dongwanzi Syenite Northern Late Carboniferous Vertical Crustal Growth in Northern North China Craton

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Performance analysis for underground gas storage reservoir in depleted gas field

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Journal of Harbin Institute of Technology(New Series) 2002年第1期9卷 75-78页

作者：谭羽飞陈家新 Sch. of Manicipal and Environ. Eng. Harbin Inst. of Technol. Harbin 150001 China

The construction of underground natural gas storage is one of the most reasonable and effective ways for basically surmounting city seasonal peak shaving and stabilizing peak waving. Owing to the heterogeneity of geological structure used as underground natural gas storage and different capacities of storing and transmitting fluid in reservoir, it is necessary make a reasonable proration for each member of the injection and production wells within the storage during peak shaving. In this paper, through analyzing the injection production performance characteristics of the underground natural gas storage in depleted gas field, an accurate mathematical model of the underground gas storage of depleted gas field is set up; characteristics of the storage performance and permeating processes were studied,history processes of underground gas storage were stimulated and major influence factors were analyzed. Specific and typical examples from actural data are included to demonstrate the relevance of the method to simulation of storage operation.

关键词： underground gas storage depleted gas field mathematical simulation performance analysis

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Modeling the effect of water vaporization and salt precipitation on reservoir properties due to carbon dioxide sequestration in a depleted gas reservoir

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Petroleum 2018年第4期4卷 385-397页

作者： Yong Tang Ruizhi Yang Xingmei Kang State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China China Petrochemical International(Ningbo)Co. LtdNinbo310500China Exploration and Development Research Institute of Changqing Oil Field Branch Company of PetroChina Xi'an710016China

Vaporization of water during both gas reservoir development and CO2 geological sequestration in saline formations can cause salt precipitation with rapid loss of formation porosity and permeability.Water vaporization and precipitation of halite around a single well from stage production to CO2 injection are studied to investigate the effect on reservoir properties in a gas reservoir.This paper identifies and quantifies post-flood dry zones and permeability changes in depleted gas reservoir after CO2 exposure with the comparison in gas production period by performing the numerical simulation with the compositional simulator.Simulation results indicate that water vaporization and salt precipitation occur during gas production,and can be intensified by CO2 injection.Dry supercritical CO2 injection vaporizes the brine promoting brine concentration and halite precipitation.The simulation indicates a drying area with a radius of 78 m around wellbore after CO2 injection.Porosity reduces with the most scope of 58%,and permeability can be decreased by up to 93.9%due to salt precipitation.And the injectivity is damaged by 99.77%at the end of injection period based on maximum permeability reduction.Moreover,six factors are investigated to conduct the influence analysis,showing that higher salinity brine,higher injection rate,higher irreducible water saturation,lower initial permeability,higher temperature and with capillary flow are conditions enhancing the salt precipitation due to dry CO2 injection.

关键词： reservoir depleted intensified

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Petrogenesis of siliceous high-Mg series:Evidence from Early Paleoproterozoic mafic volcanic rocks of the Vodlozero Domain,Fennoscandian Shield

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Geoscience Frontiers 2018年第1期9卷 207-221页

作者： M.Bogina V.Zlobin S.Svetov E.Sharkov A.Chistyakov Institute of Geology of Ore Deposits Petrography Mineralogy and Geochemistry Russian Academy of Sciences Geological Institute Russian Academy of Sciences Institute of Geology Karelian Scientific Center Russian Academy of Sciences

Compositional peculiarities of the siliceous high-Mg series(SHMS)rocks formed at the Archean-Paleoproterozoic boundary as a function of plume activity are discussed using example of Early Paleoproterozoic mafic volcanic rocks of the Vodlozero Domain,Fennoscandian Shield.These rocks are characterized by wide variations in Mg#(33-67)and Cr contents(25-1123 ppm),LREE enrichment,and weakly negative_(εNd)(from-0.7 to-2.9).The high Gd/Yb ratio in the primitive high-Mg rocks of the Vodlozero Domain suggests their generation from a garnet-bearing source.At the same time,their negative _(εNd)in combination with LREE enrichment points to the crustal contamination.A new model was proposed to explain the remarkable global-scale similarity of SHMS.Such rocks can be generated by the contamination of a high-degree(30%)partial melt derived from a depleted mantle.The lower crustal sanukitoid-type rocks can be considered as a universal crustal contaminant.Modeling showed that such mixing can provide the observed narrow_(εNd)variations in Early Paleoproterozoic volcanics.The Neoarchean sanukitoid suites,which are widespread on all cratons,presumably composed the lower crust at the beginning of the Paleoproterozoic.Therefore,this mechanism can be considered universal for the genesis of the SHMS rocks.The high-to low-Cr rock series can be produced by the fractionation of the mafic melt coupled with an insignificant crustal assimilation of felsic end members of the sanukitoid suite of the Vodlozero Domain en route to the surface,as suggested by the positive correlation of_(εNd)with Cr and Mg#,negative correlation with Th,and slight decrease of_(εNd)in the more evolved varieties.

关键词： Early Palaeoproterozoic Siliceous high-magnesian series (SHMS) rocks Sanukitoids Mantle plume depleted mantle Crustal contamination

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Chemical and Sr-Nd compositions and ^(40)Ar/^(39)Ar ages of NW-trending dolerite dikes of Burkina Faso: Evidence for a Mesoproterozoic magmatism in the West African Craton

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Geoscience Frontiers 2018年第6期9卷 1957-1980页

作者： Boukare Tapsoba Ching-Hua Lo Urbain Wenmenga Yoshiyuki Iizuka Sun-Lin Chung Gregory Shellnutt Department of Geosciences National Taiwan University UFR-SVT Département de Géologie Université Pr.Joseph Ki-Zerbo de Ouagadougou Institute of Earth Sciences Academia Sinica Department of Earth Sciences National Taiwan Normal University

The Paleoproterozoic basement of the northeastern part of the Leo-Man craton is intruded by generally NW-trending dikes. These regional scale dikes extend over 1000 km in Burkina Faso, Mali and Niger. We present chemical and Sr-Nd isotope compositions, as well as 40 Ar/39 Ar ages of these dikes with the following strikes N98°-N112°, and N114°-N124° in NE Burkina Faso. Field relationships show that the dikes are posterior to all other rock types dated between 2.26 Ga and 2.0 Ga. Chemical data indicate that the dikes are continental flood basalts and composed of low-Ti(TiO2 ≤ 2 wt.%) sub-alkaline basalts and andesites. They exhibit a minor negative Europium anomaly(0.86-0.99) and slightly fractionated REE patterns((La/Yb)_N= 2.5-9.1; Yb_N = 9.5-19.9). The ratios of Th/Ta(1.3-11.4) and Ce/Pb(5.2-58.5)suggest a varying crustal assimilation of the dike magmas during ascent in the continental crust for all studied samples. Calculated P-T conditions indicate that the magma reached temperatures of 1285 ℃(calculated from olivine compositions) and pressures of 6.9 kbar(calculated for pyroxene minerals).Calculated initial 87 Sr/86 Sr(0.70040-0.70260) and ε_(Nd)(t)=+2.1 to-3.5 at 1575 Ma,also point to a crustal contamination with the most primitive samples showing T_(DM) values of 1946 Ma and 2154 Ma. The low values of La/Ba(<0.2) and Nb/La(<1.0), contrast with the low Th/Nb(<0.9), and suggest a lithospheric mantle or subduction-modified mantle as possible source for the dikes. Sr-Nd data, Mg# and NbTa-Zr-Y-Th-Tb-Yb compositions further suggest that the most primitive samples were emplaced in a none orogenic setting and their magmas were subjected to variable crustal contaminations. Literature and the present whole rock 40 Ar/39 Ar age determinations show that the dikes were emplaced during a widespread Mesoproterozoic magmatism between 1.6 Ga and 1.2 Ga, and were affected by a thermal event causing the argon systematics resetting, best constrained by the date of sample KK1(1236 ± 20 Ma,^(40)Ar/^(36)Ar = 294 ±13, MSWD = 2.2)

关键词： Mafic dike swarm depleted mantle Mesoproterozoic Continental tholeiites Nuna West African Craton

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Re-Os isotopic system and formation age of subcontinental lithosphere mantle

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Chinese Science Bulletin 2000年第3期45卷 193-200页

作者： ZHI XiachenDepartment of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China Advance Research Center for Earth Science and Astronomy, USTC, Third World Academy of Science, Hefei 230026, China Laboratory of Chemical Geodynamics, USTC, Hefei 230026, China Department of Earth and Space Sciences University of Science and Technology of China Hefei China Advance Research Center for Earth Science and Astronomy USTC Third World Academy of Science Hefei China Laboratory of Chemical Geodynamics USTC Hefei China

The determination of the formation age of subcontinental Lithosphere Mantle (SCLM) is a widely concerned issue in mantle geochemistry. it is difficult to obtain the formation age of SCLM using lithophile isotopic systems such as Rb-Sr, Sm-Nd, U-Th-Pb, ete., but as siderophile elements, the Re-Os isotopic system provides a powerful tool for that work. Here a comprehensive review on the recent development in Re-Os dating for SCLM has been given.

关键词： Re-Os isotopic dating subcontinental lithospheric mantle mantle derived peridotites Re depleted model age whole rock isochronological age.

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Monitoring of injected CO_(2) at two commercial geologic storage sites with significant pressure depletion and/or re-pressurization histories: A case study

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Petroleum 2017年第1期3卷 138-143页

作者： Dayanand Saini Department of Physics&Engineering California State UniversityBakersfieldCA 93311USA

Majority of geologic CO_(2) storage sites for currently operated large-scale integrated carbon capture and storage projects(LSIPs)in operation around the world are depleted oil fields that have been undergone significant depletion and re-pressurization prior to injection of captured CO_(2).A better understanding of any of the implications associated with past depletion and re-pressurization histories to“out of injection zone”migration of injected CO_(2) can help in making monitoring strategies significantly more effective.Being the geologic CO_(2) storage demonstration sites for two most active LSIPs in the US,the West Hastings and the Bell Creek Oil Fields are the main focus of present study.The monitoring technologies that have been used/deployed/tested at both the normally pressured West Hastings and the subnormally pressured Bell Creek storage sites appear to adequately address any of the potential“out of zone migration”of injected CO_(2) at these sites.It would be interesting to see if any of the collected monitoring data at the West Hastings and the Bell Creek storage sites could also be used in future to better understand the viability of initially subnormally pressured and subsequently depleted and re-pressurized oil fields as secure geologic CO_(2) storage sites with relatively large storage CO_(2) capacities compared to the depleted and re-pressurized oil fields that were initially discovered as normally pressured.

关键词： geologic depletion depleted

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山东沂水杂岩岩石化学及锆石Hf同位素研究

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岩石学报 2009年第8期25卷 1872-1882页

作者：宋会侠赵子然沈其韩宋彪中国地质科学院地质研究所北京100037 北京离子探针中心北京100037

山东沂水杂岩主要由高角闪岩相至麻粒岩相变质的变基性岩和(紫苏)花岗岩岩体组成。本文主要研究了三个含紫苏辉石的黑云斜长角闪岩(YS06-19、YS06-41和YS06-29),三个含石榴子石的角闪二辉斜长麻粒岩(YS0640、YS0645、YS0649),一个含尖... 详细信息

山东沂水杂岩主要由高角闪岩相至麻粒岩相变质的变基性岩和(紫苏)花岗岩岩体组成。本文主要研究了三个含紫苏辉石的黑云斜长角闪岩(YS06-19、YS06-41和YS06-29),三个含石榴子石的角闪二辉斜长麻粒岩(YS0640、YS0645、YS0649),一个含尖晶石和石榴子石角闪二辉麻粒岩(YS06-31)和两个英灵山花岗片麻岩样品(YS06-30和YS06-48)的岩石化学和锆石Hf同位素特征。结果认为,(1)含紫苏辉石的黑云斜长角闪岩和含石榴子石的角闪二辉斜长麻粒岩对Sr、K、Rb、Ba、Ce、Th等大离子亲石元素和轻稀土元素的富集程度不同,指示了其原岩经历了不同程度的部分熔融;(2)认为英灵山花岗片麻岩是由来自于亏损地幔的基性岩部分熔融产生,这一观点同沈其韩等(2000)认识一致;(3)所研究的变基性岩的锆石Hf亏损地幔模式年龄均小于英灵山花岗片麻岩Hf亏损地幔模式年龄,指示了该变基性岩可能不是英灵山花岗片麻岩的母岩,沂水地区应该存在更古老的变基性岩石,也可能反映了这两类岩石对Hf同位素体系的保存能力不同;(4)该地区地壳生长在30亿年左右启动,大规模的地壳生长出现在2530～2740Ma。

关键词：山东沂水杂岩岩石化学锆石同位素研究 Complex Study 花岗片麻岩变基性岩 partial melting depleted mantle granulite facies metamorphism different 石榴子石麻粒岩亏损地幔斜长角闪岩 rare earth elements Shandong Province 紫苏辉石

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