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Saturation evaluation for fine-grained sediments

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Geoscience Frontiers 2023年第4期14卷 57-71页

作者： Linqi Zhu Shiguo Wu Xueqing Zhou Jianchao Cai Key Laboratory of Marine Geophysics and Georesource Institute of Deep-sea Science and EngineeringChinese Academy of SciencesSanya 572000China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China University of Chinese Academy of Sciences Beijing 100049China Sanya Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 572000China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China

Accurate quantification of the gas hydrate content in the deep sea is useful for assessing the resource potential and understanding the role of gas hydrates in the global carbon cycle.Resistivity logging data combined with Archie’s equation are often used to calculate gas hydrate saturation,but the reliability is dependent on the rationality of the empirical parameter cementation factor and saturation index.At present,an increasing number of fine-grained hydrate-rich sediment regions have been discovered worldwide through drilling efforts,and the reservoir types and hydrate distribution are diverse,which differs greatly from that of coarse-grained reservoirs of hydrate-bearing sediment.This results in vertical variations in m and n through stratigraphy.At present,the saturation evaluation effect of these reservoirs cannot be improved.In this work,a theory for the determination of the cementation factor and saturation index was first proposed to obtain reliable and variable values of the empirical parameters.Then,a hydrate saturation evaluation technique with variables m and n was formed based on the well logging data.This technique was used to evaluate complex fine-grained hydrate-bearing reservoirs in several regions worldwide.It was found that the highest n could be 16,and the log calculation results were more consistent with the core hydrate saturation.Additionally,the cause of the excessively high n values was explained from physical principles,and the result was verified with actually well log data.In future evaluations of the amount of hydrate resources in fine-grained sediment reservoirs worldwide,new saturation estimation methods should be taken into account to advance hydrate research.

关键词： Hydrate fine-grained Cementation factor Saturation index Archie Petrophysics

A fine-grained privacy protection data aggregation scheme for outsourcing smart grid

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Frontiers of Computer Science 2023年第3期17卷 187-198页

作者： Hongyang LI Xinghua LI Qingfeng CHENG School of Cyber Engineering Xidian UniversityXi’an 710071China Strategic Support Force Information Engineering University Zhengzhou 450001China

Compared with the traditional power grid,smart grid involves many advanced technologies and applications.However,due to the rapid development of various network technologies,smart grid is facing the challenges of balancing privacy,security,efficiency,and functionality.In the proposed scheme,we design a privacy protection scheme for outsourcing smart grid aided by fog computing,which supports fine-grained privacy-protected data aggregation based on user characteristics.The fog server matches the encrypted characteristics in the received message with the encrypted aggregation rules issued by the service provider.Therefore,the service provider can get more fine-grained analysis data based on user characteristics.Different from the existing outsourcing smart grid schemes,the proposed scheme can achieve real-time pricing on the premise of protecting user privacy and achieving system fault tolerance.Finally,experiment analyses demonstrate that the proposed scheme has less computation overhead and lower transmission delay than existing schemes.

关键词： smart grid data aggregation fine-grained privacy preservation real-time pricing

fine-grained P2P traffic classification by simply counting flows

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Frontiers of Information Technology & Electronic Engineering 2015年第5期16卷 391-403页

作者： Jie HE Yue-xiang YANG Yong QIAO Wen-ping DENG College of Computer National University of Defense Technology The Research Institution China Electronic Equipment & System Engineering Company

The continuous emerging of peer-to-peer(P2P) applications enriches resource sharing by networks, but it also brings about many challenges to network management. Therefore, P2 P applications monitoring, in particular,P2 P traffic classification, is becoming increasingly important. In this paper, we propose a novel approach for accurate P2 P traffic classification at a fine-grained level. Our approach relies only on counting some special flows that are appearing frequently and steadily in the traffic generated by specific P2 P applications. In contrast to existing methods, the main contribution of our approach can be summarized as the following two aspects. Firstly, it can achieve a high classification accuracy by exploiting only several generic properties of flows rather than complicated features and sophisticated techniques. Secondly, it can work well even if the classification target is running with other high bandwidth-consuming applications, outperforming most existing host-based approaches, which are incapable of dealing with this situation. We evaluated the performance of our approach on a real-world trace. Experimental results show that P2 P applications can be classified with a true positive rate higher than 97.22% and a false positive rate lower than 2.78%.

关键词： Traffic classification Peer-to-peer(P2P) fine-grained Host-based

Discriminative fine-grained network for vehicle re-identification using two-stage re-ranking

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Science China(Information Sciences) 2020年第11期63卷 147-158页

作者： Qi WANG Weidong MIN Daojing HE Song ZOU Tiemei HUANG Yu ZHANG Ruikang LIU School of Information Engineering Nanchang University School of Software Nanchang University Jiangxi Key Laboratory of Smart City Nanchang University School of Computer Science and Software Engineering East China Normal University

Research on the application of vehicle re-identification to video surveillance has attracted increasingly growing attention. Existing methods are associated with the difficulties of distinguishing different instances of the same car model owing to the incapability of recognizing subtle differences among these instances and the possibility that a subtle difference may lead to incorrect results of ranking. In this paper, a discriminative fine-grained network for vehicle re-identification based on a two-stage re-ranking framework is proposed to address these issues. This discriminative fine-grained network(DFN) is composed of fine-grained and Siamese networks. The proposed hybrid network can extract discriminative features of the vehicle instances with subtle differences. The Siamese network is rather suitable for general object re-identification using two streams of the network, while the fine-grained network is capable of detecting subtle differences.The proposed two-stage re-ranking method allows obtaining a more reliable ranking list by using the Jaccard metric and merging the first and second re-ranking lists, where the latter list is formed using the sample mean feature. Experimental results on the VeR i-776 and VehicleID datasets show that the proposed method achieves the superior performance compared to the state-of-the-art methods used in vehicle re-identification.

关键词： vehicle re-identification DFN two-stage re-ranking fine-grained Jaccard metric

Effect of Phosphorus on Mechanical Properties and Thermal Stability of fine-grained GH761 Alloy

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Journal of Materials Science & Technology 2011年第6期27卷 539-545页

作者： Shulin Yang Wenru Sun Jianxi Wang Zhimei Ge Shouren Guo Zhuangqi Hu Institute of Metal Research~ Chinese Academy of Sciences Shenyang 110016 China Shenyang Liming Aero-engine Corporations Shenyang 110043 China

The effect of phosphorus on mechanical properties and thermal stability of fine-grained GH761 alloy has been investigated. The results show that, when the content of phosphorus is in the range of 0.0007%–0.040%, there are no significant effects on the tensile properties. Phosphorus strongly affects the stress rupture life. The content of 0.023% P results in the longest life in this experiment. Compared with that of the alloy with 0.0007% P, the life is increased more than 2 times in the alloy with 0.023% P. After ageing at 700°C for 1000 h, the life reduced to some extent. However, phosphorus exhibits the similar effect on the life as before ageing. The tensile properties of the alloy are not influenced by long term ageing obviously. The present results suggested that the optimum content of phosphorus is 0.023%. The phosphorus with this content can optimize the precipitates at the grain boundaries and prevent the excessive growth of the precipitates. The combining mechanical properties of GH761 alloy can be largely improved by phosphorus addition combined with grain refinement.

关键词： Phosphorus fine-grained Mechanical properties Ageing Grain boundaries

Zero-shot fine-grained Classification by Deep Feature Learning with Semantics

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International Journal of Automation and computing 2019年第5期16卷 563-574页

作者： Ao-Xue Li Ke-Xin Zhang Li-Wei Wang The Key Laboratory of Machine Perception (MOE) School of Electronics Engineering and Computer SciencePeking University

fine-grained image classification, which aims to distinguish images with subtle distinctions, is a challenging task for two main reasons: lack of sufficient training data for every class and difficulty in learning discriminative features for representation. In this paper, to address the two issues, we propose a two-phase framework for recognizing images from unseen fine-grained classes, i.e., zeroshot fine-grained classification. In the first feature learning phase, we finetune deep convolutional neural networks using hierarchical semantic structure among fine-grained classes to extract discriminative deep visual features. Meanwhile, a domain adaptation structure is induced into deep convolutional neural networks to avoid domain shift from training data to test data. In the second label inference phase, a semantic directed graph is constructed over attributes of fine-grained classes. Based on this graph, we develop a label propagation algorithm to infer the labels of images in the unseen classes. Experimental results on two benchmark datasets demonstrate that our model outperforms the state-of-the-art zero-shot learning models. In addition, the features obtained by our feature learning model also yield significant gains when they are used by other zero-shot learning models, which shows the flexility of our model in zero-shot finegrained classification.

关键词： fine-grained image classification zero-shot learning deep feature learning domain adaptation semantic graph

Vertical Migration of fine-grained Sediments from Interior to Surface of Seabed Driven by Seepage Flows–‘Sub-Bottom Sediment Pump Action'

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Journal of Ocean University of China 2017年第1期16卷 15-24页

作者： ZHANG Shaotong JIA Yonggang WEN Mingzheng WANG Zhenhao Zhang Yaqi ZHU Chaoqi Li Bowen LIU Xiaolei Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100P.R.China Functional Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology Qingdao 266200P.R.China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100P.R.China College of Marine Geosciences Ocean University of ChinaQingdao 266100P.R.China

A scientific hypothesis is proposed and preliminarily verified in this paper: under the driving of seepage flows, there might be a vertical migration of fine-grained soil particles from interior to surface of seabed, which is defined as ‘sub-bottom sediment pump action' in this paper. Field experiments were performed twice on the intertidal flat of the Yellow River delta to study this process via both trapping the pumped materials and recording the pore pressures in the substrate. Experimental results are quite interesting as we did observe yellow slurry which is mainly composed of fine-grained soil particles appearing on the seabed surface; seepage gradients were also detected in the intertidal flat, under the action of tides and small wind waves. Preliminary conclusions are that ‘sediment pump' occurs when seepage force exceeds a certain threshold: firstly, it is big enough to disconnect the soil particles from the soil skeleton; secondly, the degree of seabed fluidization or bioturbation is big enough to provide preferred paths for the detached materials to migrate upwards. Then they would be firstly pumped from interior to the surface of seabed and then easily re-suspended into overlying water column. Influential factors of ‘sediment pump' are determined as hydrodynamics(wave energy), degree of consolidation, index of bioturbation(permeability) and content of fine-grained materials(sedimentary age). This new perspective of ‘sediment pump' may provide some implications for the mechanism interpretation of several unclear geological phenomena in the Yellow River delta area.

关键词： sediment pump action vertical migration fine-grained pore pressure seepage flows

Synchrotron radiation X-ray diffraction in situ study of fine-grained minerals in shock veins of Suizhou meteorite

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Science China Earth Sciences 2005年第6期48卷 815-821页

作者： XIE Xiande1, SHU Jinfu2 & CHEN Ming1 1. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC, 20015, USA Correspondence should be addressed to Xie Xiande Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Geophysical Laboratory Carnegie Institution of Washington Washington USA

The synchrotron radiation X-ray diffraction technique developed for in situ study ahigh pressure and temperature has also been used to investigate microscopic mineral inclusionsin ultrahigh-pressure metamorphic rocks and deep-mantle samples. Present study added twomore examples of successful utilization of synchrotron radiation X-ray diffraction technique for insitu investigations of fine-grained (0.5―30 μm in size) minerals in very thin shock melt veins othe Suizhou meteorite: ( i ) X-ray diffraction measurement of extremely small-sized vein matrixminerals, and (ii) identification of the micron-sized new mineral tuite embedded in the vein matrixIt has been revealed that the fine-grained vein matrix consists of well crystallized garnet, kamacite and troilite, and the powder diffraction pattern consisting of 17 lines with d-values, intensities( I ), relative intensities (I/Io) and Miller indices, as well as the cell parameters for the new mineratuite has also been successfully obtained. The result of present investigations has enriched thecontent of dynamic high-pressure mineralogy and that of Earth’s mantle geochemistry.

关键词： synchrotron radiation, X-ray diffraction, fine-grained minerals, Suizhou meteorite.

A fine-grained Runtime Power/Performance Optimization Method for Processors with Adaptive Pipeline Depth

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Journal of Computer Science & Technology 2011年第2期26卷 292-301页

作者：姚骏 Shinobu Miwa Hajime Shimada Shinji Tomita Graduate School of Information Science Nara Institute of Science and Technology School of Engineering Tokyo University of Agriculture and Technology Graduate School of Informatics Kyoto University Institute for Integrated Cell-Material Sciences Kyoto University

Recently, a method known as pipeline stage unification （PSU） has been proposed to alleviate the increasing energy consumption problem in modern microprocessors. PSU achieves a high energy efficiency by employing a changeable pipeline depth and its working scheme is eligible for a fine control method. In this paper, we propose a dynamic method to study fine-grained program interval behaviors based on some easy-to-get runtime processor metrics. Using this method to determine the proper PSU configurations during the program execution, we are able to achieve an averaged 13.5% energydelay-product （EDP） reduction for SPEC CPU2000 integer benchmarks, compared to the baseline processor. This value is only 0.14% larger than the theoretically idealized controlling. Our hardware synthesis result indicates that the proposed method can largely decrease the hardware overhead in both area and delay costs, as compared to a previous program study method which is based on working set signatures.

关键词： dynamic optimization energy saving fine-grained pipeline stage unification workload analysis