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Coupled model constructed to simulate the landslide dam flood discharge:a case study of Baige landslide dam,Jinsha River

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Frontiers of Earth Science 2020年第1期14卷 63-76页

作者： Hongjie WANG Yi zhou Shixin WANG Futao WANG Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China

Landslide dam,always triggered by the strong earthquake and heavy rain,is a common natural disaster around the *** this study,a coupled model was built by combining DB-IWHR model and the two-dimensional hydrodynamic model to simulate the landslide dam flood *** mapped the maximum Baige landslide dam flood inundated area based on Gaofen-1 imagery,and then simulated the process of Baige landslide dam flood discharge using this coupled *** was proved that,with 80.05%F values,the coupled model was suitable to simulate the process of landslide dam flood ***,multiple scenarios were simulated respectively by setting varying width and depth of *** results of scenarios 1-4 indicated that spillway width presented low sensibility to the peak flow in spillway and the time of its arrival,and similarly to the water depth at river cross-section and the inundated *** depth at river cross-section and the inundated area decreased as spillway width *** if spillway width varied at 10 m interval,the average variation of water depth was less than 1.82 m and the variation of inundated area was less than 2.85%.However,the results of scenarios 5-8 indicated that spillway depth was sensitive to the peak flow in spillway and its arrival time,and also to water depth at river cross-section and the inundated *** depth at river cross-section and the inundated area increased first and then started to drop with spillway depth kept *** spillway depth varied at only 2 m interval,the average variation of water depth at river cross-section basically exceeded 2 m and the variation of inundated area was more than 2.85%.

关键词： landslide dam scenario simulation flood discharge

Observations of nitrous acid and its relative humidity dependence in Shanghai

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Journal of Environmental Sciences 2006年第5期18卷 910-915页

作者： HAO Nan zhou Bin CHEN Dan CHEN Li-min Department of Environmental Science and Engineering Fudan University Shanghai 200433 China

Nitrous acid, HNO2, is an important precursor of OH radicals in the troposphere. Measurements of HNO2 and NO2, using differential optical absorption spectroscopy （DOAS）, were performed in Shanghai, China for a period from October 22, 2004 to January 4, 2005. The mean （and median） hourly concentrations of HNO2 and NO2 during this period were 1.1 （0.7） ppb and 24 （21.4） ppb respectively. A correlation between HNO2/NO2 and PM10 mass concentrations was obtained. This correlation suggests that significant heterogeneous chemical production of HNO2 may occur through NO2 reactions on aerosol surfaces. This hypothesis was further supported by detailed analysis of selected pollution episodes in this study. At the same time, the water dependence of HNO2 formation was studied by analysis of relative humidity （RH）. It showed that the maximum HNO2/NO2 ratio was increased along with RH below 70% and inhibited at RH〉70%.

关键词： DOAS heterogeneous formation nitrous acid PM,o aerosol relative humidity

Edgence: A Blockchain-Enabled Edge-Computing Platform for Intelligent IoT-Based dApps

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China Communications 2020年第4期17卷 78-87页

作者： Jinliang Xu Shangguang Wang Ao zhou Fangchun Yang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

Nowadays scalable Io T management is a bottleneck of Io T development due to the geographically dispersed distribution, fragmented ownerships, and ever-growing population of Io T devices. To intelligently manage massive decentralized applications(d Apps) in Io T usecases, Edgence(EDGe + intellig ENCE) is proposed to use edge clouds to access Io T devices and users, and then use its in-built blockchain to realize self-governing and self-supervision of the edge clouds. Edgence proposes to use masternode technology to introduce Io T devices and users into a closed blockchain system, which can extend the range of blockchain to Io T-based d Apps. Further, masternodes do good to scalability by raising the TPS(transactions per second) of the blockchain network. To support various d Apps, a three-tier validation is proposed, namely script validation, smartcontract validation, and masternode validation. To avoid energy consumption resulted by blockchain consensus, Edgence proposes a random but verifiable way to elect a masternode to generate each new block. The potential of the tailored Edgence is shown by examples of decentralized crowdsourcing and AI training.

关键词： mobile edge computing IoT crowd-intelligence blockchain dApp

Undrained semi-analytical solution for cylindrical cavity expansion in anisotropic soils under biaxial stress conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1284-1297页

作者： Lele Hou Xiaolin Weng Jibo Hu Rongming zhou School of Highway Chang’an UniversityXi’an710064China

This paper presents an undrained semi-analytical elastoplastic solution for cylindrical cavity expansion in anisotropic soil under the biaxial stress *** advanced simplified SANICLAY model is used to simulate the elastoplastic behavior of *** cavity expansion is treated as an initial value problem and solved as a system of eight first-order ordinary differential equations including four stress components and four anisotropic *** results are validated by comparing the new solutions with existing *** distributions of stress components and anisotropic parameters around the cavity wall,the expansion process,the stress yield trajectory of a soil element and the shape and size of elastoplastic boundary are further investigated to explore the cavity expansion response of soils under biaxial in situ *** results of extensive parameters analysis demonstrate that the circumferential position of the soil element and the anisotropy of the soils have noticeable impacts on the expansion response under biaxial in situ *** the present solution not only considers the anisotropy and anisotropy evolution of natural soil,but also eliminates the conventional assumption of uniform radial pressure,the solution is better than other theoretical solutions to explain the pressure test and pile installation effect of shallow saturated soil.

关键词： Cylindrical cavity expansion Anisotropic soil Undrained solution Biaxial in situ stresses

Spatiotemporal distribution and influencing factors of Ulva prolifera and Sargassum and their coexistence in the South Yellow Sea,China

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Journal of Oceanology and Limnology 2022年第3期40卷 1070-1084页

作者： Longxiao ZHENG Mengquan WU Min zhou Lianjie ZHAO College of Resources and Environmental Engineering Ludong UniversityYantai 264039China

Marine ecological disasters occurred frequently in recent years and raised widespread concerns about the ecological health of the *** analyzed the spatiotemporal distributions of Ulva prolifera and Sargassum from April to July each year between 2016 and 2020 in the South Yellow Sea using multisource(GF-1 and HJ-1A/1B)remote sensing images,combined with the MODIS sea surface temperature(SST)data,photosynthetically active radiation(PAR)data,and Quick SCAT sea surface wind(SSW)data,to explore the potential influencing *** results show that(1)*** and Sargassum appeared mainly from May to July and April to June,respectively;(2)*** showed an impact in larger spatial scope than that of *** originated in the shoal area of northern Jiangsu and finally disappeared in the sea near Haiyang-Rongcheng *** spatial scope of the impact of Sargassum tended to *** was first detected in the ocean northeast of the Changjiang(Yangtze)River estuary and disappeared near 35°N;and(3)correlation analysis showed that the SST influenced the growth rate of *** and *** had varied eff ects on *** and Sargassum at different times.A moderate light conditions could accelerate the growth and reproduction of *** and *** irradiance levels of ultraviolet radiation may cause photoinhibition and damage on *** and *** southeast monsoon and surface currents promoted the drift of *** and Sargassum from the southeast to the northwest and ***,the spatial and temporal similarities and differences between *** and Sargassum were influenced by a combination of factors during their growth processes.

关键词： Ulva prolifera Sargassum virtual-baseline floating macro algae height(VB-FAH) spatiotemporal distribution South Yellow Sea multi-source remote sensing

Convex-up Style of Deformation within Grabens in Regions of Incomplete Crossing Conjugate Normal Faults: A Numerical Simulation Investigation and Case Study

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Journal of Earth Science 2024年第3期35卷 839-849页

作者： Zheng Li Kai Wang Xiong Xiong Bing zhou School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China Department of Earth Sicences Khalifa UniversityAbu DhabiUnited Arab Emirates

Crossing conjugate normal faults(CCNFs)are extensively developed in many hydrocarbon-producing basins,generally existing in the form of incomplete ***,the effect of the non-conjugate zone of the CCNFs on the conjugate relay zone post late tectonic action has not been previously *** use 3D elastic-plastic modeling to investigate the influence of incomplete(i.e.,partially intersecting)CCNFs on the pattern of deformation of strata in the intersection region.A series of model simulations were performed to examine the effects of horizontal tectonic extension,fault size,and fault depth on the deformation of conjugate relay zones of incomplete *** analyses yielded the following results.(1)The model of incomplete conjugation predicts a convex-up style of deformation in the conjugate graben region superimposed on overall subsidence under applied horizontal tectonic extension.(2)The degree of convex-up deformation of the conjugate graben depends on the influence of the non-conjugate zone on the conjugate relay zone,which varies with the amount of horizontal tectonic extension,fault size,and fault burial depth.(3)Our results indicate that incomplete CCNFs can form convex-up deformation,similar to that in the Nanpu Sag area and provide a sound understanding of hydrocarbon migration and accumulation.

关键词： incomplete conjugate normal fault conjugate graben convex-up deformation hydrocarbons Nanpu Sag tectonics.

Mesozoic birds of China--a synoptic review

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Frontiers in Biology 2007年第1期2卷 1-14页

作者： zhou Zhonghe ZHANG Fucheng Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China

A synoptic review of the discoveries and studies of Chinese Mesozoic birds is provided in this paper.40Ar/39Ar dating of several bird-bearing deposits in the Jehol Group has established a geochronological framework for the study of the early avian *** Mesozoic birds had lasted for at least 11 Ma during about 131 Ma and 120 Ma(Barremian to Aptian)of the middle and late Early Cretaceous,*** order to further evaluate the change of the avian diversity in the Jehol Biota,six new orders and families are erected based on known genera and species,which brings the total number of orders of Chinese Mesozoic birds to 15 and highlights a remarkable radiation ever since the first appearance of birds in the Late *** Early Cretaceous birds had experienced a significant differentiation in morphology,flight,diet and *** examination of the foot of Jeholornis suggests this bird might not have possessed a fully reversed ***,the attachment of metatarsal I to the medial side of metatarsal II does not preclude trunk climbing,a pre-adaptation for well developed perching life of early *** had proved to be a key adaptation in the origin and early evolution of bird flight,and the adaptation to lakeshore environment had played an equally important role in the origin of ornithurine birds and their near-modern flight *** Chinese Early Cretaceous birds had preserved the direct evidence of their diet,showing that the most primitive birds were probably mainly insectivorous and that specialized herbivorous or carnivorous(e.g.,piscivorous)dietary adaptation had appeared only in later advanced *** only known Early Cretaceous bird embryo fossil has shown that precocial birds had occurred prior to altricial birds in avian history,and the size of the embryo and other analysis indicate it probably had a short incubation *** feathers probably have a wide range of distribution in early birds,further suggesting th

关键词： China Early Cretaceous birds

Cryptanalysis and Improvement of a New Certificateless Signature Scheme in the Standard Model

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China Communications 2021年第1期18卷 151-160页

作者： Chenhuang Wu Hui Huang Kun zhou Chunxiang Xu School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Financial Mathematics(Putian University) Fujian Province UniversityPutian 351100China School of computer Minnan Normal UniversityZhangzhou 363000China

Digital signature,as an important cryptographic primitive,has been widely used in many application scenarios,such as e-commerce,authentication,cloud computing,and so *** Public Key Cryptography(PKC)can get rid of the certificate management problem in the traditional Public Key Infrastructure(PKI)and eliminate the key-escrow problem in the identity-based ***,a new Certificateless Signature(CLS)scheme has been proposed by Kyung-Ah Shim(IEEE SYSTEMS JOURNAL,2018,13(2)),which claimed to achieve provable security in the standard ***,we present a concrete attack to demonstrate that the scheme cannot defend against the Type I *** this type of attack,the adversary can replace the public key of the signer,and then he plays the role of the signer to forge a legal certificateless signature on any ***,we give an improved CLS scheme to resist such an *** terms of the efficiency and the signature length,the improved CLS is preferable to the original scheme and some recently proposed CLS schemes in the case of precomputation.

关键词： certificateless signature standard model attack

Cogeneration of Innovative Audio-visual Content: A New Challenge for Computing Art

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Machine Intelligence Research 2024年第1期21卷 4-28页

作者： Mengting Liu Ying zhou Yuwei Wu Feng Gao Advanced Institute of Information Technology Peking UniversityHangzhou311215China School of Electronic and Computer Engineering Shenzhen Graduate SchoolPeking UniversityShenzhen 518000China Peng Cheng Laboratory Shenzhen 518000China School of Arts Peking UniversityBeijing 100871China

In recent years,computing art has developed rapidly with the in-depth cross study of artificial intelligence generated con-tent(AIGC)and the main features of ***-visual content generation has gradually been applied to various practical tasks,including video or game score,assisting artists in creation,art education and other aspects,which demonstrates a broad application *** this paper,we introduce innovative achievements in audio-visual content generation from the perspective of visual art genera-tion and auditory art generation based on artificial intelligence(Al).We outline the development tendency of image and music datasets,visual and auditory content modelling,and related automatic generation *** objective and subjective evaluation of generated samples plays an important role in the measurement of algorithm *** provide a cogeneration mechanism of audio-visual content in multimodal tasks from image to music and display the construction of specific stylized *** are still many new op-portunities and challenges in the field of audio-visual synesthesia generation,and we provide a comprehensive discussion on them.

关键词： Artificial intelligence(AI)art audio-visual artificial intelligence generated content(AIGC) multimodal artistic evalu-ation