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Reinforcement Learning-Based Sensitive Semantic Location Privacy Protection for VANETs

China Communications 2021年第6期18卷 244-260页

作者： Minghui Min Weihang Wang Liang xiao yilin xiao Zhu Han Department of Information and Communication Engineering Xiamen UniversityXiamen 361005China School of Information and Control Engineering ChinaUniversity of Mining and TechnologyXuzhou 221116China The Affiliated Hospital of China University of Mining and Technology Xuzhou 221116China Department of Electrical and Computer Engineering University of HoustonHouston TX 77004USA Beijing Key Laboratory of Mobile Computing and Pervasive Device No.6 Kexueyuan South RoadBeijing 100190China

Location-based services(LBS)in vehicular ad hoc networks(VANETs)must protect users’privacy and address the threat of the exposure of sensitive locations during LBS *** release not only their geographical but also semantic information of the visited places(e.g.,hospital).This sensitive information enables the inference attacker to exploit the users’preferences and life *** this paper we propose a reinforcement learning(RL)based sensitive semantic location privacy protection *** scheme uses the idea of differential privacy to randomize the released vehicle locations and adaptively selects the perturbation policy based on the sensitivity of the semantic location and the attack *** scheme enables a vehicle to optimize the perturbation policy in terms of the privacy and the quality of service(QoS)loss without being aware of the current inference attack model in a dynamic privacy protection *** solve the location protection problem with high-dimensional and continuous-valued perturbation policy variables,a deep deterministic policy gradientbased semantic location perturbation scheme(DSLP)is *** actor part is used to generate continuous privacy budget and perturbation angle,and the critic part is used to estimate the performance of the *** demonstrate the DSLP-based scheme outperforms the benchmark schemes,which increases the privacy,reduces the QoS loss,and increases the utility of the vehicle.

关键词： semantic location sensitivity locationbased services VANET differential privacy reinforcement learning

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Marine urease with higher thermostability, pH and salinity tolerance from marine sponge-derived Penicillium steckii S4-4

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Marine Life Science & Technology 2021年第1期3卷 77-84页

作者： Changrong Liu Yao xiao yilin xiao Zhiyong Li Marine Biotechnology Laboratory State Key Laboratory of Microbial MetabolismSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

Urease has a broad range of applications,however,the current studies on urease mainly focus on terrestrial plants or ***,it is quite necessary to determine if marine-derived ureases have diferent characteristics from terrestrial origins since the fnding of ureases with superior performance is of industrial *** this study,the marine urease produced by Penicillium steckii S4-4 derived from marine sponge Siphonochalina *** *** marine urease exhibited a maximum specifc activity of 1542.2 U mg protein−*** molecular weight of the enzyme was 183 kDa and a single subunit of 47 kDa was detected,indicating that it was a *** N-terminal amino acid sequence of the urease was arranged as GPVLKKTKAAAV with greatest similarity to that from marine algae Ectocarpus *** urease exhibited a K_(m) of 7.3 mmol L^(−1) and a V_(max) of 1.8 mmol urea min^(−1) mg protein^(−1).The optimum temperature,pH and salinity are 55℃,8.5 and 10%,*** urease was stable and more than 80%of its maximum specifc activity was detected after incubating at 25–60℃for 30 min,pH 5.5–10.0 or 0–25%salinity for 6 *** with the terrestrial urease from Jack bean,this marine urease shows higher thermostability,alkaline preference and salinity tolerance,which extends the potential application felds of urease to a great extent.

关键词： Marine urease Penicillium steckii Thermostability Alkali resistance Salinity tolerance

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Petrogenesis of Middle-Eocene granitoids and their Mafic microgranular enclaves in central Urmia-Dokhtar Magmatic Arc(Iran): Evidence for interaction between felsic and mafic magmas

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Geoscience Frontiers 2019年第2期10卷 705-723页

作者： Kazem Kazemi Ali Kananian yilin xiao Fatemeh Sarjoughian School of Geology College of ScienceUniversity of Tehran Department of Geochemistry and Environmental Science School of Earth and Space SciencesUniversity of Science and Technology of China Department of Earth Sciences Faculty of SciencesUniversity of Kurdistan

Whole rock major and trace element geochemistry together with zircon U-Pb ages and Sr-Nd isotope compositions for the Middle Eocene intrusive rocks in the Haji Abad region are presented. The granitoid hosts, including granodiorite and diorite, yielded zircon U-Pb ages with a weighted mean value of 40.0 ± 0.7 Ma for the granodiorite phase. Mafic microgranular enclaves(MMEs) are common in these plutons, and have relatively low SiO_2 contents(53.04-57.08 wt.%) and high Mg#(42.6-60.1), probably reflecting a mantle-derived origin. The host rocks are metaluminous(A/CNK = 0.69-1.03), arc-related calc-alkaline, and I-type in composition, possessing higher SiO_2 contents(59.7-66.77 wt.%) and lower Mg#(38.6-52.2); they are considered a product of partial melting of the mafic lower crust. Chondritenormalized REE patterns of the MMEs and granitoid hosts are characterized by LREE enrichment and show slight negative Eu anomalies(Eu/Eu* = 0.60-0.93). The host granodiorite samples yield(^(87)Sr/^(86)Sr);ratios ranging from 0.70498 to 0.70591,positive eNd(t) values varying from +0.21 to +2.3, and TDM2 ranging from 760 to 909 Ma, which is consistent with that of associated mafic microgranular enclaves(^(87)Sr/^(86)Sr)i = 0.705111-0.705113, ε_(Nd)(t)= +2.14 to +2.16, T_(DM2) = 697-785 Ma). Petrographic and geochemical characterization together with bulk rock Nd-Sr isotopic data suggest that host rocks and associated enclaves originated by interaction between basaltic lower crust-derived felsic and mantlederived mafic magmas in an active continental margin arc environment.

关键词： Geochemistry U-Pb geochronology Granitoid Haji Abad Low angle subduction Urumieh-Dokhtar Magmatic Arc

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Lithium Isotopic Geochemistry in Subduction Zones:Retrospects and Prospects

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 688-710页

作者： WAN Hongqiong SUN He LIU Haiyang xiao yilin CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

Subduction zones involve many complex geological processes, including the release of slabderived fluids, fluid/rock interactions, partial melting, isotopic fractionations, elemental transporting, and crust/mantle interactions. Lithium（Li） isotopes（~6Li and ~7Li） have relative mass difference up to 16%, being the largest among metal elements. Thus, Li isotopes have advantage to interprete trace various geological processes. Most importantly, during crust/mantle interactions in deep subduction zones, surface materials and mantle rocks usually have distinct Li isotopic compositions. Li isotopes can be potential tracer for subduction processes, from the onset of subduction to the release of Li from subducted slabs and interaction with mantle wedge, as well as the fate of Li in slab-derived fluids and residual slabs. Moreover, the Li isotopic composition of subducting output materials can provide useful information for understanding global Li circulation. With developments in measurement and expansion of Li isotopic database, Li isotopic geochemistry will provide more inference and be a powerful tracer for understanding subduction-related processes. This work retrospected the application of Li isotopes in tracing successive subduction processes, and made some prospects for further studies of Li isotopes.

关键词： subduction zone Li isotopes subduction-related processes Li geological tracer

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Trace Element Mobility in Subducted Marble and Associated Eclogite:Constraints from UHP Rocks in the Shuanghe Area,Central-East China

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Journal of Earth Science 2024年第1期35卷 1-15页

作者： Xingao Hou Zhiqiang Yu Shefa Chen Lei Liu yilin xiao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

In order to decipher element mobility in UHP meta-sedimentary rocks in the continental subduction zone,major and trace element compositions are investigated for a continuous profile from a representative UHP region in the Dabie *** the lithologic contact zone,contents of K,Ca,LREE,and LILE exhibit varying degrees of downward trends in both marble and eclogite toward the contact zone,indicating that marble and their associated eclogite can release a large amount of K,Ca,and a small number of LILEs and *** is the main Ti phase in both marble and *** rims around rutile can occasionally be seen in *** of Ti and HFSE exhibit a well-coupled relation among marble and eclogite,indicating that substantial Ti and HFSEs were migrated from eclogite to marble,in accord with the capacity of a melt *** and titanites in marble exhibit a relatively limited variation in Nb/Ta ratios(12.9-16.2),similar to those of titanites in eclogite(14.2-16.7),which demonstrates that rutiles and titanites in marble were sourced from eclogite because of short-distance migrations of Ti and *** to the P-T path and the temperature and pressure conditions of the peak metamorphism reported by previous studies,the eclogite associated with marble may not form supercritical fluids in the subduction zone because of the addition of carbonate minerals.

关键词： UHP metamorphism eclogite marble element migration fluid actions geochemistry

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Carbon isotope anomaly in marbles associated with eclogites from the Dabie Mountains

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Chinese Science Bulletin 1998年第2期43卷 155-160页

作者： Yongfei Zheng Bin Fu Bing Gong yilin xiao Yiliang Li Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China

This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results place constraints on the degree of crust_mantle interaction during the UHP metamorphism.

关键词： carbon isotopes marble and eclogite UHP metamorphism crust_mantle interaction Dabie Mountains.

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Reinforcement learning based energy-efficient internet-of-things video transmission

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Intelligent and Converged Networks 2020年第3期1卷 258-270页

作者： yilin xiao Guohang Niu Liang xiao Yuzhen Ding Sicong Liu Yexian Fan Department of Information and Communication Engineering Xiamen UniversityXiamen 361005China College of Information and Mechanical and Electrical Engineering Ningde Normal UniversityNingde 352100China

The video transmission in the Internet-of-Things(IoT)system must guarantee the video quality and reduce the packet loss rate and the delay with limited resources to satisfy the requirement of multimedia *** this paper,we propose a reinforcement learning based energy-efficient IoT video transmission scheme that protects against interference,in which the base station controls the transmission action of the IoT device including the encoding rate,the modulation and coding scheme,and the transmit power.A reinforcement learning algorithm state-action-reward-state-action is applied to choose the transmission action based on the observed state(the queue length of the buffer,the channel gain,the previous bit error rate,and the previous packet loss rate)without knowledge of the transmission channel model at the transmitter and the *** also propose a deep reinforcement learning based energy-efficient IoT video transmission scheme that uses a deep neural network to approximate Q value to further accelerate the learning process involved in choosing the optimal transmission action and improve the video transmission ***,both the performance bounds of the proposed schemes and the computational complexity are theoretically *** results show that the proposed schemes can increase the peak signal-to-noise ratio and decrease the packet loss rate,the delay,and the energy consumption relative to the benchmark scheme.

关键词： Internet-of-Things(IoT) video transmission reinforcement learning energy efficiency

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Formation and evolution of supercritical geofluid

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Science China Earth Sciences 2025年第1期 39-51页

作者： Huaiwei NI yilin xiao xiaolin XIONG Xiandong LIU Chunxiao GAO Yi-Xiang CHEN Yunguo LI Wan-Cai LI Xuan GUO Yang-Yang WANG Dong-Bo TAN Li ZHANG State Key Laboratory of Lithospheric and Environmental Coevolution University of Science and Technology of China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of China Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Sciences and Engineering Nanjing University State Key Lab of Superhard Materials Jilin University

In this work, we provide a comprehensive review on the formation, evolution, properties, and effects of supercritical geofluid. In Earth's interior, enhanced miscibility between H2O and silicate by the addition of special components or by the increase of pressure and temperature gives rise to supercritical geofluid with a significant amount of both H2O and silicate *** formation of supercritical geofluid in magmatic-hydrothermal systems, typified by pegmatite system, is governed by meltfluid critical curve. The formation of supercritical geofluid in metamorphic systems, typified by subducted slab, is governed by the second critical end point. Experimental results suggest that the presence of boron and fluorine in pegmatite system makes it possible to form supercritical geofluid at crustal depths, but the release of supercritical geofluid from subducted slab is withheld until almost 100 km depth. A major presence of both H2O and depolymerized structural units（monomers, dimers, etc.） endows supercritical geofluid with unique physical properties including low density, low elastic moduli, low viscosity, high diffusivity,and high electrical conductivity. Supercritical geofluid can effectively mobilize a variety of elements even including high field strength elements and heavy rare earth elements. The chemical signatures of supercritical geofluid can be inherited by metasomatized mantle and mantle-derived melts, and this could give an explanation of the oxidation of arc magmas. Phase separation of supercritical geofluid through the mechanism of spinodal decomposition leads to formation of a melt network. Multiphase fluid inclusions recovered from subduction zone rocks and pegmatites are possible relics of supercritical geofluid. Supercritical geofluid can cause electrical anomaly and low seismic velocity near the top of subducted slab, and can be linked with intermediate-focus earthquakes. Supercritical geofluid may have played a crucial role in the formation of pe

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ZirconfO2: An Excel VBA program for magmatic and hydrothermal oxygen fugacity calculation using zircon trace elements

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Journal of Earth Science 2024年

作者： Jing Lei yilin xiao CAS Key Laboratory of Crust-Mantle Materials and Environments， School of Earth and Space Sciences， University of Science and Technology of China Chinese Academy of Sciences Center of Excellence in Comparative Planetology

Oxygen fugacity of magmas and hydrothermal fluids is an important factor affecting element migration and mineralization. Zircon is an excellent monitor for oxygen fugacity of melts and fluids due to its exceptionally stable nature. However， zircon oxybarometers involve many complex algorithms leading to difficulties in use. Therefore， there is an urgent need to realize automatic calculation of various zircon oxybarometers. This study developed a Visual Basic for Applications (VBA) program， ZirconfO2， built in an ExcelTMworkbook， for calculating the oxygen fugacity of magmatic and hydrothermal fluids through the trace element characteristics of zircons. The program covers almost all the algorithms of zircon oxybarometers commonly-used so far. Through the user-friendly interface， users may input data expediently， obtain multiple results of various algorithms and find the most reliable oxygen fugacity range， effectively avoiding the possible misdirection of a single algorithm.

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

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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

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