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two-Factor Cancelable Biometrics Authenticator

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Journal of Computer Science & technology 2007年第1期22卷 54-59页

作者：彭颖涵 andrew t. B. J David N. C. L Faculty of Information Science and technology Multimedia University dalan Ayev Keroh Lama 75450 Melaka Malaysia

Biometrics-based authentication system offers advantages of providing high reliability and accuracy. However the contemporary authentication system is impuissance to compromise. If a biometrics data is compromised, it cannot be replaced and rendered unusable. In this paper, a cancelable biometrics-based authenticator is proposed to solve this irrevocability issue. the proposed approach is a two-factor authentication system, which requires both of the random data and facial feature in order to access the system. In this system, tokenized pseudo-random data is coupled with momentbased facial feature via inner product algorithm. the output of the product is then discretized to generate a set of private binary code, coined as 2factor-Hashing code, which is acted as verification key. If this biometrics-based verification key is compromised, a new one can be issued by replacing a different set of random number via token replacement. then, the compromised one is rendered completely useless. this feature offers an extra protection layer against biometrics fabrication since the verification code is replaceable. Experimental results demonstrate that the proposed system provides zero Equal Error Rate in which there is a clear separation in between the genuine and the imposter distribution populations.

关键词： cancelable biometrics face recognition geometric moments,pseudo Zernike moment

Symmetry and Period-Adding Windows in a Modified Optical Injection Semiconductor Laser Model

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Chinese Physics Letters 2012年第1期29卷 1-4页

作者： LI Xian-Feng andrew Y-t.Leung CHU Yan-Dong Department of Mathematics Lanzhou Jiaotong UniversityLanzhou 730070 Department of Civil and Architectural Engineering City University of Hong KongHong Kong

Hierarchical structural symmetry of periodic islands embedded in the chaotic region of modified optical injection semiconductor lasers(MOISLs)is expounded upon in phase *** onset of the bifurcation cascade shows remarkable accumulation *** cascade follows a specific period-adding ***-similarities and infinite spiral nestings shrinking beyond a certain point of the periodic hub are revealed to affirm the existence of self-organized distribution of periodicity and chaos in phase diagrams.

关键词： periodic bifurcation symmetry

Detecting and mapping slums using open data:a case study in Kenya

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International Journal of Digital Earth 2020年第6期13卷 683-707页

作者： Ron Mahabir Peggy Agouris Anthony Stefanidis Arie Croitoru andrew t.Crooks Department of geography and geoinformation Science George Mason UniversityFairfaxVAUSA Center for geoinformatics and geospatial Intelligence George Mason UniversityFairfaxVAUSA Center for Earth Observing and Space Research College of ScienceGeorge Mason UniversityFairfaxVAUSA Criminal Investigations and Network Analysis Center George Mason UniversityFairfaxVAUSA Department of Computational and Data Sciences George Mason UniversityFairfaxVAUSA

the worldwide slum population currently stands at over one billion,with substantial growth expected in the coming ***,slums have been mapped using information derived mainly from either physical indicators using remote sensing data,or socio-economic indicators using census *** data source on its own provides only a partial view of slums,an issue further compounded by data poverty in less-developed *** overcome such issues,this paper explores the fusion of traditional with emerging open data sources and data mining tools to identify additional indicators that can be used to detect and map the presence of slums,map their footprint,and map their *** this goal,we develop an indicator database for slums using open sources of physical and socio-economic data that can be used to characterize slum *** this database,we then leverage data mining techniques to identify the most suitable combination of these indicators for mapping *** three cities in Kenya as test cases,results show that the fusion of these data can improve the mapping accuracy of *** results suggest that the proposed approach can provide a viable solution to the emerging challenge of monitoring the growth of slums.

关键词： Slums remote sensing socioeconomic urban sustainability data mining Kenya

Structured matter creates toroidal structured light

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Light(Science & Applications) 2022年第9期11卷 1950-1951页

作者： andrew Forbes School of Physics University of the WitwatersrandJohannesburgSouth Africa

Nano-structured metasurfaces have to be tailored from artificial atoms that act as toroidal emitters,giving rise to a new form of light long predicted:"flying doughnuts"as propagating spatial-temporal electromagnetic ... 详细信息

关键词： visible matter artificial

An implantable,wireless,battery-free system for tactile pressure sensing

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Microsystems & Nanoengineering 2023年第5期9卷 309-320页

作者： Lin Du Han Hao Yixiao Ding andrew gabros thomas C.E.Mier Jan Van der Spiegel timothy H.Lucas Firooz Aflatouni andrew g.Richardson Mark g.Allen Department of Electrical and Systems Engineering School of Engineering and Applied ScienceUniversity of PennsylvaniaPhiladelphiaPAUSA Department of Neurosurgery Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Departments of Neurosurgery and Biomedical Engineering Ohio State UniversityColumbusOHUSA

the sense of touch is critical to dexterous use of the hands and thus an essential component of efforts to restore hand function after amputation or *** systems have addressed this goal with wearable tactile ***,such wearable sensors are suboptimal for neuroprosthetic systems designed to reanimate a patient’s own paralyzed ***,we developed an implantable tactile sensing system intended for subdermal *** system is composed of a microfabricated capacitive pressure sensor,a custom integrated circuit supporting wireless powering and data transmission,and a laser-fused hermetic silica *** miniature device was validated through simulations,benchtop assessment,and testing in a primate *** sensor implanted in the fingertip accurately measured applied skin forces with a resolution of 4.3 *** output from this novel sensor could be encoded in the brain with microstimulation to provide tactile *** broadly,the materials,system design,and fabrication approach establish new foundational capabilities for various applications of implantable sensing systems.

关键词： system battery fused

Multiple effects of sediment transport and geomorphic processes within flood events:Modelling and understanding

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International Journal of Sediment Research 2015年第4期30卷 371-381页

作者： Mingfu guan Nigel g.Wright P.andrew Sleigh University of Leeds

Flood events can induce considerable sediment transport which in turn influences flow *** study investigates the multiple effects of sediment transport in floods through modelling a series of hydraulic scenarios,including small-scale experimental cases and a full-scale glacial outburst flood.A non-uniform,layer-based morphodynamic model is presented which is composed of a combination of three modules:a hydrodynamic model governed by the two-dimensional shallow water equations involving sediment effects;a sediment transport model controlling the mass conservation of sediment;and a bed deformation model for updating the bed *** model is solved by a second-order godunov-type numerical *** the modelling of the selected sediment-laden flow events,the interactions of flow and sediment transport and geomorphic processes within flood events are *** is found that the inclusion of sediment transport increases peak flow discharge,water level and water depth in dam-break flows over a flat *** a partial dam breach,sediment material has a blockage effect on the flood *** comparison with the 'sudden collapse' of a dam,a gradual dam breach significantly delays the arrival time of peak flow,and the flow hydrograph is changed *** bed erosion and deposition occur within the rapid outburst flood,which scours the river channel *** is noted that the flood propagation is accelerated after the incorporation of sediment transport,and the water level in most areas of the channel is reduced.

关键词： Sediment transport Morphodynamic model Dam-break Outburst flood

Regional Moisture Source Changes Inferred from Late Holocene Stable Isotope Records

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Advances in Atmospheric Sciences 2008年第6期25卷 1021-1028页

作者： Zhonghui LIU andrew C. g. HENDERSON Yongsong HUANg Department of geological Sciences Brown University Providence RI 02912 USA Environmental Change Research Centre Department of Geography University College London 26 Bedford Way London WCIH OAP UK

Qinghai Lake, China, is located near the northern limit of the East Asian summer monsoon （EASM） and thus is an ideal region for studies of past monsoonal changes. However, isotope records from this region reflect the combined effects of multiple climatic factors, and make climatic interpretations difficult. the authors use multi-proxy records, generated from the same sediment core from Qinghai Lake, to disentangle these multiple effects in isotope records and to infer EASM variability during the late Holocene. Records of leaf wax （C2s） δD, lake carbonate 5180 and the Dunde ice core δ18O all indicate a millennial-scale depletion of mean isotopic values at -1500-1250 years before present. Compared with independent lake temperature and salinity records, the authors suggest that this depletion of long-term mean isotopic values must have resulted from changes in moisture sources in this region. In contrast, the authors attribute high-frequency （centennial timescale） C2s δD and ice core δ18O variability dominantly to a temperature effect. the multiproxy records provide a coherent picture in that many aspects of this regional climate （temperature, dryness, and moisture source） are strongly linked to the EASM variability.

关键词： East Asian summer monsoon Qinghai Lake hydrogen isotopes Late Holocene

A deep convolutional neural network for real-time full profile analysis of big powder diffraction data

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npj Computational Materials 2021年第1期7卷 671-679页

作者： Hongyang Dong Keith t.Butler Dorota Matras Stephen W.t.Price Yaroslav Odarchenko Rahul Khatry andrew thompson Vesna Middelkoop Simon D.M.Jacques andrew M.Beale Antonis Vamvakeros Department of Chemistry University College London20 Gordon StreetLondon WC1H 0AJUnited Kingdom SciML Scientific Computer DivisionSTFCRutherford Appleton LaboratoryHarwell OX110QXUnited Kingdom Finden Limited Merchant House5 East St Helens StreetAbingdon OX145EGUnited Kingdom National Physical Laboratory Hampton RoadTeddington TW110LWUnited Kingdom Flemish Institute for technological Research VITO NVBoeretang 200Mol 2400Belgium Research Complex at Harwell Rutherford Appleton LaboratoryHarwell Science and Innovation CampusDidcotOX110FA OxfordshireUnited Kingdom Present address:Diamond Light Source Harwell Science and Innovation CampusDidcotOxfordshire OX110DEUnited Kingdom Present address:the Faraday Institution Quad OneHarwell Science and Innovation CampusOX110RA OxfordshireUnited Kingdom

We present Parameter Quantification Network(PQ-Net),a regression deep convolutional neural network providing quantitative analysis of powder X-ray diffraction patterns from multi-phase *** network is tested against simulated and experimental datasets of increasing complexity with the last one being an X-ray diffraction computed tomography dataset of a multi-phase Ni-Pd/CeO_(2)-ZrO_(2)/Al_(2)O_(3) catalytic material system consisting of ca.20,000 diffraction *** is shown that the network predicts accurate scale factor,lattice parameter and crystallite size maps for all phases,which are comparable to those obtained through full profile analysis using the Rietveld method,also providing a reliable uncertainty measure on the *** main advantage of PQNet is its ability to yield these results orders of magnitude faster showing its potential as a tool for real-time diffraction data analysis during in situ/operando experiments.

关键词： network powder analysis

From a sequential pattern,temporal adjustments emerge in hummingbird traplining

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Integrative Zoology 2019年第2期14卷 182-192页

作者： Maria C.tELLO-RAMOS andrew t.HURLY Susan D.HEALY School of Biology University of St AndrewsScotlandUK Department of Biological Sciences University of LethbridgeAlbertaCanada

Animals that feed from resources that are constant in space and that refill may benefit from repeating the order in which they visit *** is a behavior known as traplining,a spatial ***,like other central-place foragers,use short traplines when moving between several rewarding *** we investigated whether traplining hummingbirds also use relevant temporal information when choosing which flowers to *** rufous hummingbirds that were allowed to visit 3 artificial flower patches in which flowers were refilled 20 min after they had been depleted repeated the order in which they visited the 3 *** they tended to visit the first 2 patches sooner than 20 min,they visited the third patch at approximately 20-min inter*** time between visits to the patches increased across the experiment,suggesting that the birds learned to wait longer before visiting a *** birds appeared to couple the sequential pattern of a trapline with temporal regularity,to some *** suggests that there is a temporal component to the repeated spatial movements flown by foraging wild hummingbirds.

关键词： foraging patterns interval timing rufous hummingbirds Selasphorus rufus