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Two furano-sesquiterpenes from the South China Sea Sponge Dysidea fragilis

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Chinese Journal of Chemistry 1995年第5期13卷 460-463页

作者： Su, JY Zhong, YL Zeng, LM wu, HM Ma, k ZHONGSHAN UNIV DEPT CHEMCANTON 510275GUANGDONGPEOPLES R CHINA CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSTATE KEY LAB BIOORGAN & NAT PROD CHEMSHANGHAI 200032PEOPLES R CHINA

A new sesquiterpene, ent-furodysin (1), has been isolated from the South China Sea Sponge Dysidea fragilis, along with a k.own sesqui-terpene, ent-furodysinin (2). The structure and relative stereochemistry of 1 and 2... 详细信息

关键词： furano-sesquiterpenes sponge Dysidea fragilis

Enhancing IoT anomaly detection performance for federated learning

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Digital Communications and Network. 2022年第3期8卷 314-323页

作者： Brett Weinger Jinoh k.m Alex Sim Mak.ya Nak.shima Nour Moustafa k.John wu Stony Brook.University Stony BrookNYUSA Lawrence Berk.ley National Laboratory BerkeleyCAUSA Texas A&M University CommerceTXUSA University of New South Wales CanberraAustralia

Federated Learning (FL) with mobile computing and the Internet of Things (IoT) is an effective cooperative learning approach. However, several technical challenges still need to be addressed. For instance, dividing the training process among several devices may impact the performance of Machine Learning (ML) algorithms, often significantly degrading prediction accuracy compared to centralized learning. One of the primary reasons for such performance degradation is that each device can access only a small fraction of data (that it generates), which limits the efficacy of the local ML model constructed on that device. The performance degradation could be exacerbated when the participating devices produce different classes of events, which is k.own as the class balance problem. Moreover, if the participating devices are of different types, each device may never observe the same types of events, which leads to the device heterogeneity problem. In this study, we investigate how data augmentation can be applied to address these challenges and improving detection performance in an anomaly detection task.using IoT datasets. Our extensive experimental results with three publicly accessible IoT datasets show the performance improvement of up to 22.9% with the approach of data augmentation, compared to the baseline (without relying on data augmentation). In particular, stratified random sampling and uniform random sampling show the best improvement in detection performance with only a modest increase in computation time, whereas the data augmentation scheme using Generative Adversarial Network. is the most time-consuming with limited performance benefits.

关键词： Data augmentation Federated learning Internet of things Anomaly detection Machine learning

Centrifugal model test on a riverine landslide in the Three Gorges Reservoir induced by rainfall and water level fluctuation

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Geoscience Frontiers 2022年第3期13卷 196-209页

作者： Fasheng Miao Yiping wu Ák.s Török.Linwei Li Yang Xue Faculty of Engineering China University of GeosciencesWuhan 430074China Engineering Research Center of Rock.Soil Drilling&Excavation and Protection Ministry of EducationWuhan 430074China Department of Construction Materials and Engineering Geology Budapest University of Technology and EconomicsBudapestHungary College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,mak.ng it necessary to investigate the failure mode of such riverside *** centrifugal test is considered to be the most realistic laboratory model,which can reconstruct the required *** this study,the Liangshuijing landslide in the Three Gorgers Reservoir area is selected for a scaled centrifugal model experiment,and a water pump system is employed to retain the rainfall *** the techniques of digital photography and pore water pressure transducers,water level fluctuation is controlled,and multi-physical data are thus obtained,including the pore water pressure,earth pressure,surface displacement and deep *** analysis results indicate that:Three stages were set in the test(waterflooding stage,rainfall stage and drainage stage).Seven transverse crack. with wide of 1–5 mm appeared during the model test,of which 3 crack. at the toe landslide were caused by reservoir water fluctuation,and the crack. at the middle and rear part were caused by *** rainfall process,the maximum displacement of landslide model reaches 3 *** the maximum deformation of the model exceeds 12 cm at the drainage *** failure process of the slope model can be divided into four stages:microcrack. appearance and propagation stage,thrust-type failure stage,retrogressive failure stage,and holistic failure *** the thrust-type zone caused by rainfall was connected or even overlapped with the retrogressive failure zone caused by the drainage,the landslide would start,which displayed a typical composite failure *** failure mode and deformation mechanism under the coupling actions of water level fluctuation and rainfall are revealed in the model test,which could appropriately guide for the analysis and evaluation of riverside landslides.

关键词： Riverine landslide The Three Gorges Reservoir Centrifugal model test Rainfall Fluctuation of water level

A STUDY OF RATE-DEPENDENCE AT ELEVATED TEMPERATURE FOR AN Al-Cu-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 618-624页

作者： Y.Q.wu H.J.Shi k.S.Zhang k.y Laboratory of Failure Mechanics Department of Engineering Mechanics Tsinghua UniversityBeijing 100084 China Department of Engineering Mechanics North-Western Polytechnical University Xi'an 710072 ChinaKey Laboratory of Failure Mechanics Department of Engineering Mechanics Tsinghua UniversityBeijing 100084 ChinaDepartment of Engineering Mechanics North-Western Polytechnical University Xi'an 710072 China

The hot deformation of an Al-Cu-Mg alloy was studied in the two temperature ranges (room temperature-300℃ and 400℃-480℃). The rate-independent flow curves are typical of elasto-plastic response with significant work.hardening followed by strain softening below 300℃. Similar dislocation structures with high density tangled into grain interiors were observed by TEM, which suggests that the process of obstacles arresting mobile dislocations results in this macroscopically rate-independence. At 400-480℃, all rate dependent flow behaviors characterized by a continuous softening after an initial work.hardening at a small plastic strain show large tensile elongations. Long dislocation segments around the second phases infer their good mobility to climb across obstacles. Grain boundary morphology observed by TEM suggests that the capacity of the grain boundaries to absorb the dislocations sensitively accounts for the rate-dependent mechanical properties.

关键词： rate dependence elevated temperature dislocations,grain boundary

Material and structural instabilities of single-wall carbon nanotubes

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Acta Mechanica Sinica 2008年第3期24卷 285-288页

作者： J.wu k.C.Hwang J.Song Y.Huang FML Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Department of Mechanical Science and Engineering University of Illinois1206 W.Green StreetUrbanaIL 61801USA Department of Civil and Environmental Engineering and Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA

The nonlinear atomistic interactions usually involve softening behavior. Instability resulting directly from this softening are called the material instability, while those unrelated to this softening are called the structural instability. We use the finite-deformation shell theory based on the interatomic potential to show that the tension instability of single-wall carbon nanotubes is the material instability, while the compression and torsion instabilities are structural instability.

关键词： Carbon nanotubes Instability

COMPARISON OF AMINOLEVULINIC ACID AND ITS METHYL ESTER MEDIATED PHOTOCYTOTOXICITY ON HUMAN NASOPHARYNGEAL CARCINOMA CELLS

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Journal of Innovative Optical Health Sciences 2012年第2期5卷 25-33页

作者： CHRISTINE M.N.YOW RICk. W.k.wu ZHENG HUANG Medical Laboratory Science Department of Health Technology Informatics Hong k.ng Polytechnic University Hong Kong SARChina Department of Radiation Oncology University of Colorado Denver COUSA MOE k.y Laboratory of OptoElectronic Science and Technology for Medicine Fujian Normal University FuzhouChina

Nasopharyngeal carcinoma(NPC)is a prevalent cancer in some areas of southern *** explore the potential of photodynamic therapy(PDT)for the treatment of NPC,a small molecule prodrug 5-aminolevulinic acid(ALA)and its methyl ester(MAL)mediated PDT was studied in *** results showed that human NPC cells were sensitive to both ALA-and MAL-mediated ***,ALA was more effective than MAL,possiblly due to a higher efficiency of ALA on producing endogenous protoporphyrin(PpIX)in NPC *** ALA nor MAL caused any significant *** ALA-based PDT might be a useful modality in the treatment ofNPC.

关键词： Aminolevulinic acid methylaminolevulinate nasopharyngeal carcinoma photodynamic therapy

Engineering Novel Molecular Beacon Constructs to Study Intracellular RNA Dynamics and Localization

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Genomics, Proteomics & Bioinformatics 2017年第5期15卷 279-286页

作者： Zhao Ma Xiaotian wu Christopher J.k.ueger Antony k.Chen Department of Biomedical Engineering College of Engineering Peking University Beijing 100871 China Wallace H Coulter Department of Biomedical Engineering Georgia Institute of Technology Atlanta GA 30332 USA

With numerous advancements in novel biochemical techniques, our k.owledge of the role of RNAs in the regulation of cellular physiology and pathology has grown significantly over the past several decades. Nevertheless, detailed information regarding RNA processing, traffick.ng, and localization in living cells has been lack.ng due to technical limitations in imaging single RNA transcripts in living cells with high spatial and temporal resolution. In this review, we discuss tech- niques that have shown great promise for single RNA imaging, followed by highlights in our recent work.in the development of molecular beacons （MBs）, a class of nanoscale oligonucleotide-probes, for detecting individual RNA transcripts in living cells. With further refinement of MB design and development of more sophisticated fluorescence microscopy techniques, we envision that MB-based approaches could promote new discoveries of RNA functions and activities.

关键词： Y-O-methyl RNA Phosphorothioate Molecular beacon RNA dynamics Single-molecule RNAimaging

The adjoint-based Two Oceans One Sea State Estimate(TOOSSE)

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Journal of Oceanology and Limnology 2022年第1期40卷 1-21页

作者： Xiaowei WANG Chuanyu LIU Armin k.HL wu GENG Fan WANG Detlef STAMMER CAS k.y Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Laboratory for Ocean Dynamics and Climate Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Institut für Meeresk.nde Universität HamburgHamburg D20146Germany State k.y Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

An eddy-resolving four-dimensional variational(adjoint)data assimilation and state estimate was constructed for the low-to mid-latitude Pacifi c,Indian Oceans,and South China Sea based on the framework.of“Estimating the Circulation and Climate of the Oceans(ECCO)”.It is named as the Two Oceans One Sea State Estimate(TOOSSE).It fi ts a model to a number of modern observations of 2015-2016,including the Argo fl oat temperature and salinity,satellite altimetric sea surface anomalies,by adjusting initial temperature and salinity,sea surface boundary conditions,and back.round diapycnal diff *** total,~50%of the original model-data misfi ts have been eliminated,and the estimated state agreed well with a variety of independent observations at meso-to large scales,and on the intra-seasonal to interannual *** variability is systematically strengthened in TOOSSE and closer to observations than that without data assimilation,which is especially evidenced by the improved simulation of the mesoscale tropical instability waves(TIWs).Adjustments to ocean surface forcing parameters exhibit both large and frontal/mesoscale structures,and the magnitude reach 20%-100%of the fi rst guesses;the adjustments to diapycnal diff usivity exhibit an obvious elevation(decrement)in(below)the thermocline in the equatorial *** results indicate that TOOSSE represents a dynamically and thermodynamically consistent ocean state estimate of the 2015-2016 Indo-Pacifi c Ocean,and can be widely utilized for regional process studies.

关键词： Pacifi c Ocean Indian Ocean South China Sea adjoint four-dimensional variational data assimilation

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基于特征融合和模板更新的孪生网络跟踪算法

电光与控制 2025年第1期32卷 41-47,85页

作者：吴国瑞王峰李杰太原理工大学电子信息与光学工程学院山西晋中030000 太原理工大学电气与动力工程学院太原030000

针对现有孪生网络跟踪算法仅使用主干网络最后一层的特征进行相似度匹配,以及缺少有效模板更新策略的问题,提出基于多尺度特征融合和自适应模板更新的孪生网络跟踪算法。首先,结合深度过参数化卷积设计非填充单元,提取更深层的前景特征... 详细信息

针对现有孪生网络跟踪算法仅使用主干网络最后一层的特征进行相似度匹配,以及缺少有效模板更新策略的问题,提出基于多尺度特征融合和自适应模板更新的孪生网络跟踪算法。首先,结合深度过参数化卷积设计非填充单元,提取更深层的前景特征和语义背景;然后,设计新的全局-局部特征融合模块,充分聚合浅、中层特征的全局和局部信息,捕获丰富的浅层外观特征和中层过渡特征;最后,采用自适应模板更新机制在线更新模板。为验证算法的有效性,在公开数据集上对所提算法进行详尽评估,实验结果显示,所提算法在OTB2015和VOT2018数据集上的精确度分别达到0.878和0.588,GOT10k.据集上平均重叠率达到0.526,优于其他主流算法。

关键词：目标跟踪孪生网络计算机应用多层特征融合模板更新

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