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International journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1206-1215页

作者： Siddharth Yadav S.P.Tewari j.K.Singh S.C.Ram Department of Mechanical Engineering Indian Institute of Technology(BHU)Varanasi 221005India Department of Metallurgical Engineering Indian Institute of Technology(BHU)Varanasi 221005India

This study investigated the microstructure,physical,and mechanical properties of die-cast A308 alloy subjected to mechanical vibration during *** frequencies(0,20,30,40,and 50 Hz)at constant amplitude(31μm)were employed using a power amplifier as the power input device.X-ray diffraction,optical microscopy,and scanning electron microscopy were used to examine the morphological changes in the cast samples under stationary and vibratory *** features of the castings were evaluated using Image j *** average values of metallurgical features,including primaryα-Al grain size,dendrite arm spacing,average area of eutectic silicon,aspect ratio,and percentage porosity,reduced by 34%,59%,56%,22%,and 62%,respectively,at 30 Hz frequency compared with stationary *** tests of the cast samples showed that the yield strength(YS),ultimate tensile strength(UTS),percentage elongation(%EL),and microhardness(HV)increased by 8%,13%,17%,and 16%,respectively,at 30 Hz frequency compared with stationary *** fractured surface of the tensile specimens exhibited mixed-mode fracture behavior because of brittle facets,cleavage facets,ductile tearing,and dimple *** presence of small dimples showed that plastic deformation occurred before fracture.

关键词： mechanical vibration microstructures microhardness tensile strength fractography

A PID-incorporated Latent Factorization of Tensors Approach to Dynamically Weighted Directed Network Analysis

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IEEE/CAA journal of Automatica Sinica 2022年第3期9卷 533-546页

作者： Hao Wu Xin Luo MengChu Zhou Muhyaddin j.Rawa Khaled Sedraoui Aiiad Albeshri Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714and also with the University of Chinese Academy of SciencesBeijing 100049China Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewark NJ 07102 USA IEEE Center of Research Excellence in Renewable Energy and Power Systems Department of Electrical and Computer EngineeringFaculty of Engineeringand K.A.CARE Energy Research and Innovation CenterKing Abdulaziz UniversityJeddah 21589Saudi Arabia College of Engineering King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Computer Science King Abdulaziz UniversityJeddah 21481Saudi Arabia

A large-scale dynamically weighted directed network(DWDN)involving numerous entities and massive dynamic interaction is an essential data source in many big-data-related applications,like in a terminal interaction pattern analysis system(TIPAS).It can be represented by a high-dimensional and incomplete(HDI)tensor whose entries are mostly *** such an HDI tensor contains a wealth knowledge regarding various desired patterns like potential links in a DWDN.A latent factorization-of-tensors(LFT)model proves to be highly efficient in extracting such knowledge from an HDI tensor,which is commonly achieved via a stochastic gradient descent(SGD)***,an SGD-based LFT model suffers from slow convergence that impairs its efficiency on large-scale *** address this issue,this work proposes a proportional-integralderivative(PID)-incorporated LFT *** constructs an adjusted instance error based on the PID control principle,and then substitutes it into an SGD solver to improve the convergence *** studies on two DWDNs generated by a real TIPAS show that compared with state-of-the-art models,the proposed model achieves significant efficiency gain as well as highly competitive prediction accuracy when handling the task of missing link prediction for a given DWDN.

关键词： Big data high dimensional and incomplete(HDI)tensor latent factorization-of-tensors(LFT) machine learning missing data optimization proportional-integral-derivative(PID)controller

Polarization-independent multimode interference coupler with anisotropy-engineered bricked metamaterial

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Photonics Research 2022年第4期10卷 I0001-I0009页

作者： Carlos Perez-Armenta Alejandro Ortega-Monux jose Manuel Luque-Gonzalez Robert Halir Pedro j.Reyes-Iglesias jens Schmid Pavel Cheben Inigo Molina-Fernandez j.Gonzalo Wanguemert-Perez Telecommunication Research Institute(TELMA) Universidad de MalagaCEI Andalucia TECHE.T.S.I.Telecomunicacion29010 MalagaSpain Bionand Center for Nanomedicine and Biotechnology Parque Tecnologico de AndaluciaMalaga 29590Spain National Research Council Canada OttawaOntario K1A 0R6Canada

Many applications, including optical multiplexing, switching, and detection, call for low-cost and broadband photonic devices with polarization-independent operation. While the silicon-on-insulator platform is well positioned to fulfill most of these requirements, its strong birefringence hinders the development of polarizationagnostic devices. Here we leverage the recently proposed bricked metamaterial topology to design, for the first time, to our knowledge, a polarization-independent 2 × 2 multimode interference coupler using standard 220 nm silicon thickness. Our device can be fabricated with a single etch step and is optimized for the O-band,covering a wavelength range of 160 nm with excess loss, polarization-dependent loss, and imbalance below 1 dB and phase errors of less than 5°, as demonstrated with full three-dimensional finite-difference time-domain simulations.

关键词： polarization multimode multiplexing

ON THE ZEROS OF QUOTIENTS OF BESSEL FUNCTIONS

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Chinese Annals of Mathematics,Series B 2000年第3期21卷 285-296页

作者： A.FRIEDMAN B.HU j.j.L.VELAZQUEZ DepartmentofMathematics UniversityofMinnesotaMinneapolisMN55455USA. DepartmentofMathematics UniversityofNotreDameNotreDameIN46556USA. DepartamentodeMatematicaAplicada FacultaddeMatematicasUniversidadComplutense28040MadridSpain.

The paper studies the zeros of 2mIm/Im-1- (m+1)I1 /I0, where Im are the Bessel functions.

关键词： Zeros Quotient Bessel function

Effectiveness of ultrafine bubbles and gamma irradiation treatments to improve seed viability and vigor of Albizia chinensis(Osbeck)Merr.

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journal of Forestry Research 2022年第5期33卷 1607-1613页

作者： Dede j.Sudrajat Anindyta Putri Y.Aris Purwanto Iskandar Z.Siregar Forest Tree Seed Technology Research and Development Center Jl.Pakuan CiheuleutPO BOX 105BogorWest JavaIndonesia Department of Silviculture Faculty of Forestry and EnvironmentIPB UniversityJl.Lingkar Kampus DramagaBogor 16680West JavaIndonesia Department of Mechanical and Biosystem Engineering IPB UniversityJl.Lingkar Kampus DramagaBogor 16680West JavaIndonesia

Ultrafine bubbles and low doses of gamma irradiation had a positive effect on seed *** research tested the effectiveness of ultrafine bubbles(UFB)water and gamma irradiation for improving the viability and vigor of Albizia chinensis(Osbeck)*** that had been stored for four years.A completely randomized two-factor experiment,i.e.,UFB water and gamma irradiation treatments,were used to determine the best seed *** UFB water treatment had a significant effect on all seed germination parameters;the gamma irradiation treatment did not have a significant effect on improving the viability and vigor of the seeds,with a very low initial germination(11.7%).Soaking the seeds in UFB water for 30 min gave the best germination(51.3%).These improvements also occurred in other germination parameters such as germination rate,germination value,radicle length and vigor *** UFB water treatment has the potential to improve the germination of seeds with low physiological qualities.

关键词： Albizia chinensis Gamma rays Germination Ultrafine bubbles

Enhanced corrosion resistance of phytic acid coated magnesium by stearic acid treatment

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Transactions of Nonferrous Metals Society of China 2013年第5期23卷 1237-1244页

作者： R.K.GUPTA K.MENSAH-DARKWA j.SANKAR D.KUMAR Engineering Research Center for Revolutionizing Metallic Biomaterials(ERC-RMB) North Carolina A&T State University

A green chemical conversion coating for magnesium was obtained with a phytic acid solution. The microstructure and corrosion properties of phytic acid conversion coated magnesium were further improved by soaking in stearic acid solution. The phytic acid conversion coated magnesium after soaking in the stearic acid showed no micro-cracks and the surface became very smooth. The corrosion behavior of the uncoated and coated magnesium samples was studied by electrochemical methods. The corrosion resistance of the stearic acid treated sample was much higher than that of phytic acid conversion coated magnesium or uncoated magnesium. The electrochemical results indicated that the stearic acid treated coating provided effective corrosion protection to the magnesium sample.

关键词： magnesium phytic acid stearic acid corrosion impedance spectroscopy

jOURNAL OF ZHONGNAN UNIVERSITY OF ECONOMICS AND LAW

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中南财经政法大学学报 2008年第4期 142-144页

作者： .4 .j .1

isoAOT40:An improved ozone exposure index based on the Annual Ozone Spectrum Profile(AO3SP)

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journal of Forestry Research 2022年第6期33卷 1949-1955页

作者： Evgenios Agathokleous Costas j.Saitanis Stefanos Agathokleous Chrysanthos Savvides Vicent Calatayud Pierre Sicard Collaborative Innovation Center On Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044People’s Republic of China Research Center for Global Changes and Ecosystem Carbon Sequestration&Mitigation School of Applied MeteorologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China Lab of Ecology and Environmental Science Agricultural University of AthensIera Odos 7511855 AthensGreece The Cyprus Institute NicosiaCyprus Department of Labour Inspection Ministry of Labour and Social InsuranceNicosiaCyprus Fundación CEAM Parque TecnológicoC/Charles R.Darwin14PaternaSpain ARGANS 260 route du Pin MontardBiotFrance

Abstarct In recognition of the rising threats of groundlevel ozone(O_(3))pollution to forests,agricultural crops,and other types of vegetation,accurate and realistic risk assessment is urgently *** accumulated O_(3)exposure over a concentration threshold of 40 nmol mol-1(AOT40)is the most commonly used metric to investigate O3 exposure and its effects on vegetation and to conduct vegetation risk *** is also used by international regulatory authorities for deriving critical levels and setting standards to protect vegetation against surface O_(3).However,fixed periods of the growing season are used universally,yet growing seasons vary with latitudes and elevations,and the periods of plant lifespan also differ among annual ***,we propose the concept of the Annual O_(3)Spectrum Profile(AO_(3)SP)and apply it to calculate the profile of AOT40 throughout the year(AAOT40SP,Annual AOT40 Spectrum Profile)using the International Organization for Standardization(ISO)weeks as a shorter window ISO-based accumulated *** moving time periods of three(for crops)or six(for forests)months,the i so AOT40 behavior throughout the year can be examined as a diagnostic tool for O_(3)risks in the short-or long-term during the lifecycle of local *** this analysis,AOT40(i so AOT40)that is most representative for the local conditions and specific situations can be identified,depending on the exact growing season and lifecycle of the target *** applied this novel approach to data from five background monitoring stations located at different elevations in *** results show that the AAOT40SP approach can be used for improved and more realistic assessment of O3 risks to *** AO_(3)SP approach can also be applied using metrics other than AOT40(exposure-or flux-based),adding a new dimension to the way O_(3)risk to vegetation is assessed.

关键词： Air pollution AOT40 index Ozone risk assessment Critical levels Vegetation exposure metric

Improving TRAIL-induced apoptosis in cancers by interfering with histone modifications

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Cancer Drug Resistance 2020年第4期3卷 791-803页

作者： Bao-jie Zhang Deng Chen Frank j.Dekker Wim j.Quax University of Groningen Department of Chemical and Pharmaceutical BiologyGroningen Research Institute of PharmacyUniversity of GroningenGroningen 9713 AVThe Netherlands

Epigenetic regulation refers to alterations to the chromatin template that collectively establish differential patterns of gene ***-translational modifications of the histones play a key role in epigenetic regulation of gene *** this review,we provide an overview of recent studies on the role of histone modifications in *** tumour-selective ligands such as tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)are well-considered as promising anti-tumour therapies,we summarise strategies for improving TRAIL sensitivity by inhibiting aberrant histone modifications in *** this perspective we also discuss new epigenetic drug targets for enhancing TRAIL-mediated apoptosis.

关键词： Epigenetics histone modification tumor necrosis factor-related apoptosis-inducing ligand selective epigenetic inhibitors apoptosis

Community participation in cultural heritage and environmental policy formulation in Botswana

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Chinese journal of Population,Resources and Environment 2018年第2期16卷 171-180页

作者： Goemeone E.j Mogomotsi Patricia K Mogomotsi Reniko Gondo Tshenolo j Madigele Department of Legal Services Office of the Vice Chancellor University of Botswana Okavango Research Institute University of Botswana Department of Theology and Religious Studies University of Botswana

Cultural heritage does not have direct economic benefits. However, if properly managed it can stimulate social cohesions, improving the environment and have beneficial economic spin offs for the local communities. This paper discusses the role of communities in the formulation of the policies concerning their local environment. It argues that community engagement by policy makers is important in giving legitimacy and ownership of the policies. Furthermore, this paper discusses the potential of cultural heritage in diversifying the economy in Botswana. This paper recommends for the re-assessment of the relationship between the state and local communities which is critical in resuscitating the seemingly ailing community business organizations. In conclusion, it argues for the sustainable management of cultural heritage as a social and economic resource in the next 50 years of Botswana's independence.

关键词： Cultural heritage sustainable economic growth local communities policy formulation