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Towards Task-Free Privacy-Preserving Data Collection

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China Communications 2022年第7期19卷 310-323页

作者： Zhibo Wang Wei yuan Xiaoyi Pang Jingxin Li Huajie Shao School of Cyber Science and Engineering Wuhan University430072 China School of Cyber Science and Technology Zhejiang University310027 China State Key Laboratory of Integrated Services Networks Xidian University710071 China Department of Computer Science College of William and MaryWilliamsburgVA23186 USA

With the rapid developments of Internet of Things(IoT)and proliferation of embedded devices,large volume of personal data are collected,which however,might carry massive private information about attributes that users do not want to *** privacy-preserving methods have been proposed to prevent privacy leakage by perturbing raw data or extracting task-oriented features at local ***,they would suffer from significant privacy leakage and accuracy drop when applied to other tasks as they are designed and optimized for predefined *** this paper,we propose a novel task-free privacy-preserving data collection method via adversarial representation learning,called TF-ARL,to protect private attributes specified by users while maintaining data utility for unknown downstream *** this end,we first propose a privacy adversarial learning mechanism(PAL)to protect private attributes by optimizing the feature extractor to maximize the adversary’s prediction uncertainty on private attributes,and then design a conditional decoding mechanism(ConDec)to maintain data utility for downstream tasks by minimizing the conditional reconstruction error from the sanitized *** the joint learning of PAL and ConDec,we can learn a privacy-aware feature extractor where the sanitized features maintain the discriminative information except *** experimental results on real-world datasets demonstrate the effectiveness of TF-ARL.

关键词： IoT privacy protection data collection adversarial learning deep learning

A tectono-thermal perspective on the petroleum generation,accumulation and preservation in the southern Ordos Basin, North China

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Petroleum Science 2024年第3期21卷 1459-1473页

作者： Peng Yang Zhan-Li Ren Jin-Hua Fu Hong-Ping Bao Hui Xiao Zheng Shi Kun Wang yuan-yuan Zhang Wen-Hui Liu Wen-Hou Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an710069ShanxiChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Exploration and Development Research Institute of PetroChina Changqing Oilfield CompanyXi'an710018ShaanxiChina Shaanxi Key Lab of Petroleum Accumulation Geology School of Earth Science and EngineeringXi'an Shiyou UniversityXian710065ShaanxiChina Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxi214126JiangsuChina

The southern Ordos Basin has excellent petroleum exploration ***,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are *** this study,we analyzed the present geothermal field,paleo-geothermal gradient,maturity of the hydrocarbon source rocks,uplift and cooling process and tectono-thermal evolution *** the study area,for the Ordovician,Permain and the Triassic strata,the present temperature is low(3070℃)in the southeastern area but high(80140℃)in the northwestern *** paleogeothermal gradient varied from 24℃/km to 30℃/km with a heat flow of 58—69 m W/m^(2)(i.e.,a medium-temperature basin).The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source *** vitrinite reflectance(Ro)values of the Triassic strata are>0.7%and the thermal maturity reached the middlemature oil generation *** Rovalues of the Permian-Ordovician strata are>1.8%and the thermal maturity reached the over-mature gas generation *** southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian(452 Ma),Late Triassic(215 Ma),Late Jurassic(165160 Ma),End-Early Cretaceous(110100 Ma)and Cenozoic(since 40 Ma).A large-scale tectonothermal event occurred at the End-Early Cretaceous(110100 Ma),which was controlled by lithospheric extension,destruction and *** event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and *** southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau,uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic *** southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the *** str

关键词： Fission-track dating Vitrinitereflectance Geothermal field Tectono-thermal evolution Petroleum geology Ordos Basin

Distribution of Helium Resources in Weihe Basin,Central China:Insight from 3D Magnetic Inversion

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Journal of Earth Science 2022年第4期33卷 977-992页

作者： Xuliang Feng Bingqiang yuan Yuhong Li Chunguan Zhang Lijun Song School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065China Shaanxi Key Laboratory of Petroleum Accumulation Geology Xi'an Shiyou UniversityXi'an 710065China Xi'an Center China Geological SurveyXi'an 710054China

There is promising indication of helium-rich natural gas in Weihe ***,the lack of a detailed investigation on the origin and the spatial distribution of helium source rocks(mainly Yanshanian granites)limits the helium potentiality evaluation in Weihe Basin(WB).We performed three-dimensional(3 D)inversions of magnetic data in Weihe Basin and its adjacent areas to figure out the crustal thermal structure and the temporal-spatial distribution of deep granite in the *** on this,we have proposed a geological model of helium accumulation and predicted the potential area of helium *** results of 3 D magnetic inversion indicate that the granites in the deep Weihe Basin are mostly located at the central and southern parts of the basin,which are connected spatially with the granites in the North Qinling Orogenic *** granites were all derived from largescale intra-continental orogeny in the Qinling area during the mid-Mesozoic,providing a good material basis for crust-derived helium in the *** local uplift of the Curie surface makes the thermal fluid more actively,which contributes to helium *** faults developed in the WB are the migration pathway of crust-derived helium and the upward migration of the mantle-derived *** wells with high percentage helium are mostly located near the Weihe fault and the areas on the south of *** Wugong-Xi’an-Lantian area in the central and the Lintong-Weinan-Tongguan area in the eastern Weihe Basin are the most promising helium distribution ***,the region from the north of Taibai Mountain to Baoji City in the western Weihe Basin may also be another potential area of Helium resource.

关键词： Weihe Basin helium accumulation magnetic anomaly three-dimensional inversion Curie point depth

Nondestructive estimation of bok choy nitrogen status with an active canopy sensor in comparison to a chlorophyll meter

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Pedosphere 2020年第6期30卷 769-777页

作者： Rongting JI Weiming SHI yuan WANG Hailin ZHANG Ju MIN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Department of Plant and Soil Sciences Oklahoma State UniversityStillwater OK 74078-6028USA

Precise estimation of vegetable nitrogen(N)status is critical in optimizing N fertilization ***,nondestructive and accurate N diagnostic methods for vegetables are relatively *** our two-year field experiment,we evaluated whether an active canopy sensor(GreenSeeker)could be used to nondestructively predict N status of bok choy(Brassica rapa ***)compared with a chlorophyll *** showed that the normalized difference vegetation index(NDVI)and ratio vegetation index(RVI)generated by the active canopy sensor were well correlated with the aboveground biomass(AGB)(r=0.698–0.967),plant N uptake(PNU)(r=0.642–0.951),and root to shoot ratio(RTS)(r=-0.426 to-0.845).Compared with the chlorophyll meter,the active canopy sensor displayed much higher accuracy(5.0%–177.4%higher)in predicting AGB and PNU and equal or slightly worse(0.54–1.82 times that of the chlorophyll meter)for *** sensor-based NDVI model performed equally well in estimating AGB(R2=0.63)and PNU(R2=0.61),but the meter-based model predicted RTS better(R2=0.50).Inclusion of the days after transplanting(DAT)significantly improved the accuracy of sensor-based AGB(19.0%–56.7%higher)and PNU(24.6%–84.6%higher)estimation *** findings suggest that the active canopy sensor has a great potential for nondestructively estimating N status of bok choy accurately and thus for better N recommendations,especially with inclusion of DAT,and could be applied to more vegetables with some verification.

关键词： aboveground biomass GreenSeeker model prediction N diagnosis normalized difference vegetation index plant N uptake root to shoot ratio ratio vegetation index soil and plant analyer development(SPAD)

Predicting the grades of Astragali radix using mass spectrometrybased metabolomics and machine learning

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Journal of Pharmaceutical Analysis 2021年第5期11卷 611-616页

作者： Xinyue Yu Jingxue Nai Huimin Guo Xuping Yang Xiaoying Deng Xia yuan Yunfei Hua yuan Tian Fengguo Xu Zunjian Zhang Yin Huang Key Laboratory of Drug Quality Control and Pharmacovigilance China Pharmaceutical UniversityMinistry of EducationNanjing210009China Department of Pharmaceutical Analysis School of PharmacyChina Pharmaceutical UniversityNanjing210009China Center for Biological Technology Anhui Agricultural UniversityHefei230036China

Astragali radix(AR,the dried root of Astragalus)is a popular herbal remedy in both China and the United *** commercially available AR is commonly classified into premium graded(PG)and ungraded(UG)ones only according to the *** uncover novel sensitive and specific markers for AR grading,we took the integrated mass spectrometry-based untargeted and targeted metabolomics approaches to characterize chemical features of PG and UG samples in a discovery set(n=16 batches).A series of five differential compounds were screened out by univariate statistical analysis,including arginine,calycosin,ononin,formononetin,and astragalosideⅣ,most of which were observed to be accumulated in PG samples except for astragalosideⅣ.Then,we performed machine learning on the quantification data of five compounds and constructed a logistic regression prediction ***,the external validation in an independent validation set of AR(n=20 batches)verified that the five compounds,as well as the model,had strong capability to distinguish the two grades of AR,with the prediction accuracy>90%.Our findings present a panel of meaningful candidate markers that would significantly catalyze the innovation in AR grading.

关键词： Astragali radix Metabolomics Machine learning Quality markers Prediction model

The solution and exsolution characteristics of natural gas components in water at high temperature and pressure and their geological meaning

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Petroleum Science 2012年第1期9卷 25-30页

作者： Gao Gang Huang Zhilong Huang Baojia yuan Jian Tong Chuanxin State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China Exploration and Development Research Institutes CNOOC ZhanjiangGuangdong 524057China Chuanxi Production Factory Southwest Oil and Gas Field BranchSINOPECDeyangSichuan 618000China

The processes of solution in, and exsolution from, formation water influence the component content of natural gas by contrasting the relative contents of components before the natural gas dissolves in water and those after exsolving from water under different conditions of high temperatures and pressures. Compared with the composition of original natural gas, the relative content of methane and nitrogen increased after the natural gas dissolved in water. The increase of nitrogen content exceeds that of methane, but the content of ethane, propane, pentane etc reduced. At the same temperature and with pressure increasing the content of methane increased and that of heavier hydrocarbons reduced. At the same pressure the content of methane increased quickly from 90~C to 120~C, and the content of heavier hydrocarbons reduced. But at even higher temperatures, the increase of methane slowed down and the content of heavier hydrocarbons increased slightly. At the same temperature and different pressures, heavier hydrocarbons reduced much more with increasing carbon atom number, while with temperature increasing the content difference of heavier hydrocarbons reduced. Therefore, the influence of the solution and exsolution should be considered in the study of the migration and accumulation mechanism of natural gas.

关键词： Methane heavier hydrocarbon nitrogen formation water exsolution

DNA Reaction Network Mimicking the Basic Steps of Synaptic Communication

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Chinese Journal of Chemistry 2023年第11期41卷 1313-1318页

作者： Minghao Hu Yuqiang Hu Wenqian yuan Zhen Zhang Tongbo Wu School of Pharmacy Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430030 China

Biological systems use intricate networks of chemical reactions to exchange information. How to simulate complex systems with simple strand-displacement reactions is crucial to broaden the application scenario of the DNA reaction network. Here, we report the artificial DNA reaction network to mimic the operation and function of biological information transfer via strand-displacement reaction. DNA is used as simple artificial analogs to schematize structures and transmit information. Using chemical synapses in neural networks as an example, we show that the proposed network enables core functions of biological systems, such as the long-term potential of synapses, which underpin learning and memory. Also, we performed the simple “silicon mimetic” to link electronic circuits to chemical network-based biological structures. As such, synaptic communication simulated by the DNA reaction network provides a complete demonstration for designing artificial reaction networks based on the essence of information interaction.

关键词： Reaction networks Strand-displacement cascades DNA nanotechnology Synapse Nucleic acids Fluorescence Synthetic biology

BDSec:Security Authentication Protocol for BeiDou-Ⅱ Civil Navigation Message

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China Communications 2024年第6期21卷 206-218页

作者： Wu Zhijun Zhang yuan Yang Yiming Wang Peng Yue Meng School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China School of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China

Due to the lack of authentication mechanism in BeiDou navigation satellite system(BDS),BD-Ⅱ civil navigation message(BDⅡ-CNAV) are vulnerable to spoofing attack and replay *** solve this problem,we present a security authentication protocol,called as BDSec,which is designed by using China’s cryptography Shangyong Mima(SM) series algorithms,such as SM2/4/9 and Zu Chongzhi(ZUC)*** BDSec protocol,both of BDⅡ-CNAV and signature information are encrypted using the SM4 algorithm(Symmetric encryption mechanism).The encrypted result is used as the subject authentication *** protocol applies SM9 algorithm(Identity-based cryptography mechanism) to protect the integrity of the BDⅡ-CNAV,adopts the SM2 algorithm(Public key cryptosystem) to guarantee the confidentiality of the important session information,and uses the ZUC algorithm(Encryption and integrity algorithm) to verify the integrity of the message authentication serial number and initial information and the information in authentication initialization sub-protocol *** results of the SVO logic reasoning and performance analysis show that BDSec protocol meets security requirements for the dual user identity authentication in BDS and can realize the security authentication of BDⅡ-CNAV.

关键词： BDII civil navigation messages(BDIICNAV) BeiDou navigation satellite system(BDS) identity-based cryptography mechanism navigation message authentication protocol(BDSec)

Electrical and thermal conductivity of Earth's core and its thermal evolution——A review

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Acta Geochimica 2022年第4期41卷 665-688页

作者： yuan Yin Qingwen Zhang Youjun Zhang Shuangmeng Zhai Yun Liu State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China International Research Center for Planetary Science College of Earth SciencesChengdu University of TechnologyChengdu610059China Institute of Atomic and Molecular Physics Sichuan UniversityChengdu610065China Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang550081China

The Earth’s core is composed of iron,nickel,and a small amount of light elements(e.g.,Si,S,O,C,N,H and P).The thermal conductivities of these components dominate the adiabatic heat flow in the core,which is highly correlated to *** we review a large number of studies on the electrical and thermal conductivity of iron and iron alloys and discuss their implications on the thermal evolution of the Earth’s *** summary,we suggest that the Wiedemann-Franz law,commonly used to convert the electrical resistivity to thermal conductivity for metals and alloys,should be cautiously applied under extremely high pressure-temperature(P-T)conditions(e.g.,Earth’s core)because the Lorentz number may be P-T *** date,the discrepancy in the thermal conductivity of iron and iron alloys remains between those from the resistivity measurements and the thermal diffusivity modeling,where the former is systematically *** studies reconcile the electrical resistivity by first-principles calculation and direct measurements,and this is a good start in resolving this *** to an overall higher thermal conductivity than previously thought,the inner core age is presently constrained at~1.0 ***,light elements in the core would likely lower the thermal conductivity and prolong the crystallization of the inner ***,whether thermal convection can power the dynamo before the inner core formation depends on the amounts of the proper light elements in the *** works are needed to establish the thermal evolution model of the core.

关键词： Earth’s core Electrical and thermal conductivity Iron and its alloys Thermal evolution Geodynamo