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No-reference synthetic image quality assessment with convolutional neural network and local image saliency

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Computational Visual Media 2019年第2期5卷 193-208页

作者： Xiaochuan wang Xiaohui Liang bailin Yang Frederick w.b.Li State Kay Laboratory of Virtual Reality Technology and System Beihang UniversityBeijing 100191China School of Computer Science&Information Engineering Zhejiang Gongshang UniversityHangzhou 310018China Department of Computer Science University of DurhamUnited Kingdom

Depth-image-based rendering(DIbR) is widely used in 3 DTV, free-viewpoint video, and interactive 3 D graphics applications. Typically, synthetic images generated by DIbR-based systems incorporate various distortions, particularly geometric distortions induced by object dis-occlusion. Ensuring the quality of synthetic images is critical to maintaining adequate system service. However, traditional 2 D image quality metrics are ineffective for evaluating synthetic images as they are not sensitive to geometric distortion. In this paper, we propose a novel no-reference image quality assessment method for synthetic images based on convolutional neural networks, introducing local image saliency as prediction weights. Due to the lack of existing training data, we construct a new DIbR synthetic image dataset as part of our contribution. Experiments were conducted on both the public benchmark IRCCyN/IVC DIbR image dataset and our own dataset. Results demonstrate that our proposed metric outperforms traditional 2 D image quality metrics and state-of-the-art DIbR-related metrics.

关键词： image quality assessment synthetic image depth-image-based rendering(DIbR) convolutional neural network local image saliency

Nanophase Decomposition of a Zn-Al based Alloy Zn_(68)Al_(10)Cu_(22)

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Journal of Materials Science & Technology 2004年第6期20卷 687-690页

作者： Y.H.Zhu w.b.Lee S.To Advanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong ChinaAdvanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong ChinaAdvanced Materials Research Center Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China

The nanostructural evolution and phase transformation of the films of a Zn-Al based alloy (Zn68Al10Cu22 in wt pct) have been studied by using X-ray diffraction and scanning electron microscopy. Nanostructural thin films of the Zn-AI based alloy were produced by using an electron beam deposition technique. It was found that a nanocrystalline phase η'n had a strong preferred crystal orientation at (0002) crystal planes in the as-deposited films. During ageing at 220℃, the decomposition of nanophase η'n started with clustering to form Z-zones, and transitionai phase, which was accompanied by an eutectoid decomposition of the η'n phase: η'n β'eut T'. Decomposition, such as clustering and the formation of the Z-zones, and the transitionai phase etc. were observed in the nanophase β'eut. The formation and the decomposition of the transitionai phase of micrometers in size were involved in the decomposition of the main nanophase η'n. The mechanism of the Z-zones formation and the stability of nanophases were discussed.

关键词： Ageing Nanostructure Nanophase stability Zn-Al based alloy film

Total teleportation of zero-and one-photon entangled states in running waves

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Chinese Physics b 2008年第1期17卷 60-63页

作者： w.b.Cardoso A.T.Avelar b.baseia N.G.de Almeida Instituto de Física Universidade Federal de Goiás 74.001-970 Goinia (GO) Brazil Nuícleo de Pesquisas em Física Universidade Catlica de Goiás 74.605-220 Goinia (GO) Brazil

Inspired by a recent paper [2002 J. Opt. b 4 316] we present an alternative scheme to teleport an entanglement of zero- and one-photon states of a running-wave field. The scheme employs only linear optical elements pl... 详细信息

关键词： total teleportation entangled states linear optical elements

COMPLEXITY OF SYSTEM MAINTAINAbILITY ANALYSIS bASED ON THE INTERPRETIVE STRUCTURAL MODELING METHODOLOGY： TRANSDISCIPLINARY APPROACH

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Journal of Systems Science and Systems Engineering 2016年第2期25卷 254-268页

作者： A. Ertas M.w. Smith D. Tate w.D. Lawson T.b. baturalp Department of Mechanical Engineering Texas Tech University Lubbock TX USA 79410 Department of Industrial Design Xi 'an Jiaotong-Liverpool University Suzhou 215123 Jiangsu China Department of Civil Engineering Texas Tech University Lubbock TX USA 79410

This paper outlines a diagnostic approach to quantify the maintainability of a Commercial off-the-Shelf （COTS）-based system by analyzing the complexity of the deployment of the system components. Interpretive Structural Modeling （ISM） is used to demonstrate how ISM supports in identifying and understanding interdependencies among COTS components and how they affect the complexity of the maintenance of the COTS based System （CbS）. Through ISM analysis we have determined which components in the CbS contribute most significantly to the complexity of the system. with the ISM, architects, system integrators, and system maintainers can isolate the COTS products that cause the most complexity, and therefore cause the most effort to maintain, and take precautions to only change those products when necessary or during major maintenance efforts. The analysis also clearly shows the components that can be easily replaced or upgraded with very little impact on the rest of the system.

关键词： COTS based System maintainability complexity Interpretive Structural Modeling

Microstructure and mechanical optimization of probeless friction stir spot welded joint of an Al-Li alloy

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Journal of Materials Science & Technology 2018年第10期34卷 1739-1746页

作者： Q. Chu w.Y. Li X.w. Yang J.J. Shen A. Vairis w.Y. Feng w.b. wang State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical University Xi'an710072 China Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics Geesthacht 21502 Germany Mechanical Engineering Department TEl of Crete Heraklion Crete 71004 Greece China PSw Center Beijing 100024 China

In this work, a third generation AI-Li alloy has been successfully spot welded with probeless friction stir spot welding （P-FSSw）, which is a variant of conventional friction stir welding. The box-behnken exper-imental design in response surface methodology （RSM） was applied to optimize the P-FSSw parameters to attain maximum tensile/shear strength of the spot joints. Results show that an optimal failure load of 7.83 kN was obtained under a dwell time of 7.2 s, rotation speed of 950 rpm and plunge rate of 30 mm/rain. Sufficient dwell time is essential for heat conduction, material flow and expansion of the stir zone to form a sound joint. Two fracture modes were observed, which were significantly affected by hook defect. In addition to mechanical testing, electron backscattering diffraction （EbSD） and differential scanning calorimetry （DSC） were used for microstructure evolution and property analysis. The precipitation of GP zone and AI3Li as well as the ultrafine grains were responsible for the high microhardness in the stir zone.

关键词： Probeless friction stir spot welding Precipitation Mechanical property Fracture mechanism

Fabrication and modelling of Si_(3)N_(4)ceramics with radial grain alignment generated through centripetal sinter-forging

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Journal of Materials Science & Technology 2022年第31期126卷 1-14页

作者： Da-wang Tan Zhen-Yong Lao wei-Ming Guo Akira Kondo Takahiro Kozawa Makio Naito Kevin Plucknett Hua-tay Lin Department of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Joining and welding Research Institute Osaka University11-1 MihogaokaIbarakiOsaka 567-0047Japan Department of Mechanical Engineering Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada

Silicon nitride(Si_(3)N_(4))based ceramics are one of the most attractive advanced engineering materials,which have been widely used under high-speed rotational operation or for mechanical contacts across a curved *** the present study,rotationally symmetric texturing of Si_(3)N_(4),with radial grain align-ment,was obtained by centripetal sinter-forging(CSF)of a partially sintered *** average values of the included angles between the c-axis of the local Si_(3)N_(4)grain and radial direction were approxi-mately 16.4°and 11.0°,on the section plane perpendicular to the pressing direction,and parallel to both the pressing and radial directions,*** compressive strain in the pressing direction forced the ceramic body to flow towards the central axis,resulting in compressive strain in the tangential di-rection and tensile strain in the radial direction.A fundamental physical model was created to simulate the grain rotation during the 3-dimentional strain reorientation,which revealed the rod-like grain would preferentially rotate toward the center of the sample under the CSF *** addition,due to the fric-tion between the sample surface and the pressing punch,the increased shear strain could enhance the Si_(3)N_(4)grain ***,ceramics with rod-like grains perpendicular to the curved side sur-face could be anticipated by applying the centripetal forming concept in a controlled manner.

关键词： Si_(3)N_(4)ceramic Texture Radial grain alignment Modeling CSF

A Note on Teleportation of an Arbitrary Two-Particle State without bell-State Measurement in Cavity QED

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Communications in Theoretical Physics 2009年第8期52卷 241-243页

作者： A.D.dSouza w.b.Cardoso A.T.Avelar b.baseia Instituto de Fisica Universidade Federal de Goias

we present a scheme using four two-level atoms and a bimodal cavity to get approximate conditional teleportation of an arbitrary entangled atomic state without using the bell-state measurement.

关键词： teleportation bell-state bimodal cavity

Comment on “Approximate and Conditional Teleportation of an Unknown Atomic State without bell-State Measurement with Two-Photon Interaction”

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Communications in Theoretical Physics 2009年第7期52卷 41-44页

作者： A.D.dSouza w.b.Cardoso A.T.Avelar b.baseia Instituto de Física Universidade Federal de Goiás

In a previous work [Commun. Theor. Phys. 45 （2006） 79] a scheme was presented for approximate and conditional teleportation of an unknown atomic state in a QED-cavity without bell-state measurement via two-photon Jaynes-Cummings model in the effective Hamiltonian approach. This comment presents an alternative method, based on the so called ＂full two-photon Jaynes-Cummings Hamiltonian approach＂. Accordingly, it describes the evolution of the two-photon degenerate process for arbitrary average photon number inside the cavity, as the correct way to implement teleportation in this scenario.

关键词： teleportation bell-state measurement cavity QED two-photon interaction

Sorption of Perfluorooctane sulfonate(PFOS) including its isomers on hydrargillite as a function of pH,humic substances and Na2SO4

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Journal of Environmental Sciences 2022年第1期34卷 263-272页

作者： Jean-Noel Uwayezu Leo w.Y.Yeung Mattias bäckström Man-Technology-Environment Research Centre(MTM) Örebro University70182ÖrebroSweden

Perfluorooctane sulfonate(PFOS)is a persistent organic pollutant(POP)and emergent contaminant that are widespread in the *** the mechanisms controlling the distribution of PFOS and its isomers between hydrargillite and the water phase is important in order to study their redistribution and mobility in the *** study investigated the effects of pH,humic acid,fulvic acid and Na_(2)SO_(4) on sorption of PFOS isomers to hydrargillite.A mixture of PFOS isomers was spiked into water and hydrargillite was added to the system and shaken for one day;the system was tested with different aqueous *** of PFOS isomers in the aqueous phase were quantified using an ultra-performance liquid chromatograph coupled to a triple quadrupole mass *** results showed that the distribution coefficients of PFOS isomers were found to be 0.76,0.71,0.93 and 0.90 at pH 6.5,for 3-/4-/5-PFOS,6-/2-PFOS,L-PFOS and total PFOS *** distribution coefficients increased at lower pH and decreased at alkaline *** presence of humic substances(HS)increased the sorption slightly at the environmental pH of 6.5,although a competition effect was observed during acidic conditions.A tendency of PFOS distribution to hydrargillite in the presence of Na_(2)SO_(4) was like its behavior in the presence of HS although the mechanisms behind the sorption were interpreted *** study revealed that L-PFOS was readily sorbed when no other chemicals were added or in 20 mg/L FA or 100 mg/L Na_(2)SO_(4).we suggest that an increase in PFOS sorption in the presence of HS may be due to hydrophobic mechanisms while Na_(2)SO_(4) contributed to increased sorption through ionic strength effects.

关键词： Hydrargillite Perfluorooctane sulfonate Sorption Humic substances Electrostatic,Ionic strength