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Axisymmetric and three-dimensional flow simulation of a mixed compression supersonic air inlet

Propulsion and Power Research 2020年第1期9卷 51-61页

作者： m.Abedi R.Askari J.Sepahi-Younsi m.R.Soltani Department of Aerospace Engineering Sharif University of TechnologyTehranIran mechanical Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran Visiting Professor William E.Boeing Department of Aeronautics and AstronauticsUniversity of WashingtonWashingtonU.S.A.

The flow through an axisymmetric supersonic mixed-compression air inlet has been simulated numerically to investigate the effects and the necessity of the three-dimensional(3D)modeling in comparison with the axisymmetric *** this purpose,a supersonic inlet has been simulated numerically via axisymmetric and 3D CFD solvers,using the steady state Reynolds-averaged Navier-Stokes equations along with the SST k-ωturbulence model,for a free-stream mach number of 2.0 and at zero degrees angle of *** grid for the 3D cases was a 14.4-degree sector,instead of a 360-degree domain one,with rotational periodic boundary condition for the side *** results show that both static and total pressure distributions match well with the experimental data for both the axisymmetric and the 3D *** the prediction of performance parameters is the main goal of simulations,it seems that the axisymmetric simulation provides adequate accuracy,and the 3D simulation one is not the best *** 3D numerical simulation results in an in-depth study on the supersonic inlets,including the shock wave-boundary layer interaction,the location of the terminal normal shock wave,and consequently the separation *** an axisymmetric supersonic inlet in an axisymmetric flow condition,3D effects are not strong enough to have a significant influence on the inlet performance for all operational ***,it seems that 3D effects play an important role in both critical and supercritical operating conditions during the steady state operation.

关键词： Supersonic inlet Axisymmetric simulation Three-dimensional simulation Inlet performance Shock-boundary layer interaction

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Nanotrains and Self-Assembled Two-Dimensional Arrays Built from Carboranes Linked by Hydrogen Bonding of Dipyridones

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Nano Research 2008年第5期1卷 412-419页

作者： Takashi Sasaki Jason m.Guerrero Ashley D.Leonard James m.Tour Department of Chemistry Department of Mechanical Engineering and Materials ScienceRice UniversityMS 2226100 Main St.HoustonTexas 77005USA

The strong hydrogen bonding ability of 2-pyridones were exploited to build nanotrains on *** wheels on axles difunctionalized with 2-pyridone hydrogen bonding units were synthesized and displayed spontaneous formation of linear nanotrains by self-assembly on SiO_(2)or mica *** using atomic force microscopy confi rmed linear formations with lengths up to 5μm and heights within the range of the molecular height of the carborance-tipped axles.

关键词： Nanovehicles nanotrains 2-pyridone hydrogen bonding self-assembly

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The Genetics of Speciation： Considering Early-Acting Isolation, Hybrid Evolution, and Epigenetic mechanisms

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Current Zoology 2013年第5期59卷 654-657页

作者： Amber m. RICE, Editor Lehigh University Department of Biological Sciences Bethlehem PA 18015 USA amber.rice@Lehigh.edu

Since Darwin＇s time, evolutionary biologists have sought to understand how species arise. The study of speciation remains a focus of evolutionary biology, and since the early 204 century, characterizing the genetics underlying this process has also become a central goal. much research into the genetics of speciation has cen- tered on identifying the genes underlying reproductive isolating mechanisms, or ＇speciation genes＇（see Nosil and Schluter, 2011 for a discussion of this term）. With information about such genes available from many sys- tems, general questions about how speciation proceeds may be addressed： How many genes contribute to speciation？ Is reproductive isolation more commonly the result of divergence in protein-coding regions or regulatory regions？ Is reproductive isolation more fre- quently the result of natural selection or genetic drift？（Coyne and Orr, 2004; Nosil and Schluter, 2011）. Given recent advances in technology, such questions have be- come accessible in systems that were previously intrac- table for studying the genetics of speciation. moreover, with this increase in the accessibility of genetic analyses for non-model systems, a broader set of questions about the genetics of speciation can now be addressed.

关键词：遗传学特性生物学形态进化遗传机制基因漂移物种形成混合表观

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Heterogeneous transfer functions multi-layer perceptron (mLP) for meteorological time series forecasting

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International Journal of modeling, Simulation, and Scientific Computing 2015年第2期6卷 49-55页

作者： C.Voyant m.L.Nivet CPaoli m.muselli G.Notton University of Corsica SPE CNRS UMR 613420250 CorteFrance University of Galatasaray Computer Engineering Department No:36 34357 Ortak¨oyIstanbulTurkey

In this paper,we propose to study four meteorological and seasonal time series(TS)coupled with a multi-layer perceptron(mLP)*** chose to combine two transfer functions for the nodes of the hidden layer,and to use a temporal indicator(time index as input)in order to take into account the seasonal aspect of the studied *** results of the prediction concern two years of measurements and the learning step,eight independent *** show that this methodology can improve the accuracy of meteorological data estimation compared to a classical mLP modeling with a homogenous transfer function.

关键词： Artificial neural network meteorology time series transfer function

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Development of chemometric model for characterization of non-wood by FT-NIR data

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Journal of Bioresources and Bioproducts 2020年第3期5卷 196-203页

作者： mohammad Nashir Uddin Taslima Ferdous Zahidul Islam m.Sarwar Jahan m.A.Quaiyyum BCSIR Laboratories DhakaBangladesh Council of Scientific and Industrial Research(BCSIR)Dhaka 1205Bangladesh Department of Applied Chemistry and Chemical Engineering University of DhakaDhaka 1000Bangladesh

In this study,a model for prediction of lignocellulose components of agricultural residues has been developed with Fourier Transformed Near Infrared(FT-NIR)spectroscopy *** calibration techniques(Principal Component Regression(PCR)and Partial Least Square Regression(PLSR))were assessed for prediction of lignin,holocellulose,α-cellulose,pentosan and ash,and found the PLSR better for lignin,holocellulose andα-*** PCR also produced better results for quantification of pentosan and *** range(7000-5000 cm^(-1))showed more informative than other parts of the spectral *** PLSR showed maximum value of R^(2)(R^(2)=0.91%)for prediction of *** the prediction of pentosan,the PCR was better(R^(2)=0.68%).The PCR also showed better results(R^(2)=86%)for quantification of *** determine amount of lignin,the PLSR was the best(R^(2)=0.83%)when the spectral data were de-trained and smoothed with Savitzky-Golay(S-G)filtering *** prediction ofα-cellulose,the PLSR was the best model(R^(2)=0.94%)when the data were pretreated with mean *** the best alternatives inNear Infrared(NIR)data preprocessing and calibration techniques,methods for quantification of lignocellulose components of agricultural residues have been developed which is rapid,cost effective,and less chemical intensive and easily usable in pulp and paper industries and pulp testing laboratories.

关键词： Agricultural residue multivariate modeling Lignocellulose component

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Graft survival and visual outcome after simultaneous penetrating keratoplasty and cataract extraction

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International Journal of Ophthalmology(English edition) 2013年第3期6卷 385-389页

作者： mansour m. Al-mohaimeed Department of Ophthalmology College of Medicine Qassim University

AIm: To evaluate the indications, complications, and visual and graft survival outcomes in eyes that had undergone simultaneous cataract extraction and penetrating keratoplasty (PKP). ·mETHODS: We described a retrospective study of 101 patients who had undergone simultaneous cataract extraction and PKP at King Khaled Eye Specialist Hospital between January 1, 2001, and December 31, 2002. All patients were followed up postoperatively with maximum follow-up 68 months. ·RESULTS: The mean age of patients was 61 years. The mean overall follow -up was 27 months. The most common indications for surgery were corneal scarring (45.5% ), previous failed graft (15.8% ), corneal ulcer (12.9% ), Fuchs endothelial dystrophy (8.9% ), stromal dystrophy (2.9% ), and other conditions (14.5% ). Overall, 69 grafts (68.3% ) remained clear at final follow -up. Previous glaucoma or postoperative glaucoma had no statistically significant effects on graft outcome (P >0.05). The graft rejection rate (17.8% ) was a significant risk factor for failure (P =0.00). Age, gender, indications for surgery, corneal graft diameter, and intraoperative vitreous loss had no statistically significant effects on the PKP outcome (P >0.05). Postoperative visual acuity was significantly associated with preoperative visual acuity (P ming a combined procedure results in more rapid visual rehabilitation and good graft clarity.

关键词： penetrating keratoplasty cataract extraction graft failure

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Interfacial reaction and growth behavior of reaction layer of Si_3N_4/Si_3N_4 joint brazed by Cu-Zn-Ti filler alloy

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中国有色金属学会会刊：英文版 2005年第S2期15卷 261-265页

作者：张杰周玉 m.Naka School of materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Joining and Welding Research Institute Osaka University Ibaraki Osaka 567-0047 Japan

Si3N4 ceramic was jointed to itself using a filler alloy of Cu-Zn-Ti by the reaction between Ti and Si3N4. The microstructure of the interface in the joint is found to be Si3N4 ceramic/TiN reaction layer/Ti5Si3 reaction layer. The grain size of the TiN and Ti5Si3 reaction layer is 0.1μm and 1-2μm, respectively. There is no crystal orientation relationship between TiN reaction layer and Si3N4 ceramic or Ti5Si3 reaction layer. The kinetic equation for calculating the thickness of the reaction layer was obtained. When a （CuZn）85Ti15 alloy is used as the filler alloy, the apparent activation energy of the growth of the reaction layer is 201.69kJ/mol.

关键词： Si3N4 ceramic Cu-Zn-Ti filler alloy interfacial reaction kinetic

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Delay Testing Viability of Gate Oxide Short Defects

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Journal of Computer Science & Technology 2005年第2期20卷 195-200页

作者： J.m.Gallière m.Renovell F.Azais Y.Bertrand Laboratoired＇InformatiqueRobotiquemicroèlectroniquedemontpellierLIRmm-UmII UniversitddeMontpellierH：SciencesetTechniquesduLanguedocUMRC5506CNRS-161rueAda34392MontpellierCedex5France

Gate Oxide Short (GOS) defects are becoming predominant as technology is scaling down. Boolean and IDDQ testing of this defect has been widely studied but there is no paper dedicated to delay testing of this defect. So, this paper studies the delay behavior of Gate Oxide Short faults due to pinhole in the gate oxide. The objective of this paper is to give a detailed analysis of the behavior of the GOS defect taking into account the random parameter of the defect such as the GOS resistance and the GOS location. Because an accurate analysis is desired, the bi-dimensional array will be *** a complete analysis is desired, we derive the dynamic characteristic of the GOS as a function of the GOS resistance and location. It is demonstrated that i) GOS has a significant impact on gate delay, ii) GOS located close to the source of the transistor and with small resistance has very high impact.

关键词： VLSI 延迟测试 GOS 集成电路

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Sequence assembly using next generation sequencing data —challenges and solutions

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Science China(Life Sciences) 2014年第11期57卷 1140-1148页

作者： CHIN Francis Y.L. LEUNG Henry C.m. YIU S.m. Department of Computer Science The University of Hong Kong

Sequence assembling is an important step for bioinformatics *** the help of next generation sequencing(NGS)technology,high throughput DNA fragment(reads)can be randomly sampled from DNA or RNA molecular ***,as the positions of reads being sampled are unknown,assembling process is required for combining overlapped reads to reconstruct the original DNA or RNA *** with traditional Sanger sequencing methods,although the throughput of NGS reads increases,the read length is shorter and the error rate is *** introduces several problems in ***,paired-end reads instead of single-end reads can be sampled which contain more *** existing assemblers cannot fully utilize this information and fails to assemble longer *** this article,we will revisit the major problems of assembling NGS reads on genomic,transcriptomic,metagenomic and metatranscriptomic *** will also describe our IDBA package for solving these *** package has adopted several novel ideas in assembling,including using multiple k,local assembling and progressive depth *** with existence assemblers,IDBA has better performance on many simulated and real sequencing datasets.

关键词： genomic assembling de Bruijn graph paired-end reads next generation sequencing

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Thermal behaviour analysis in a porcelainhoused ZnO surge arrester by computer simulations and thermography

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High Voltage 2019年第3期4卷 173-177页

作者： Arthur F.Andrade Edson G.Costa Josué m.B.Fernandes Helem m.m.Alves Cícero R.C.Amorim Filho Centre of Electrical Engineering and Informatics Federal University of Campina GrandeCampina GrandeBrazil Department of Electrical Engineering Federal University of Campina GrandeCampina GrandeBrazil

In this article,an analysis of heat transfer in a porcelain-housed ZnO surge arrester is *** to the fact that ZnO-based surge arresters are key components for protection and reliability of electrical systems,it is necessary to seek techniques to assure correct *** porcelain-housed arresters,the air gap leads to an increased thermal resistance between the ambient and the varistor ***,a thermal analysis must consider convection and radiation heat transfer mechanisms,besides heat *** study proposes the use of computational simulations in combination with thermography as a tool for a temperature-based estimation of the varistor *** the analysis,temperature rise tests were performed in a 69-kV ceramic-housed arrester to measure material emissivity and produce data to fit the simulated ***,the thermal response of the surge arresters subject to an impulsive energy input was *** simulations allow to relate varistors temperature and housing temperature with regard to a specified amount of dissipated *** obtained results show that the used technique can be an effective method for arrester monitoring and may allow to define assessing criteria for a porcelain-housed arrester based on housing temperature measurements.

关键词： behaviour specified ambient

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