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The Power of an Idea: The International Impacts of the Grand challenges for Engineering

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Engineering 2016年第1期2卷 4-7页

作者： c.d.mote jr. dame Ann dowling 周济 US National Academy of Engineering (NAE) Royal Academy of Engineering (RAE) and Chinese Academy of Engineering (CAE)

Since the dawn of civilization, advances in the fields of engi- neering, science, and technology have played an indispensable role in shaping humans＇ social and economic development. Now people face a host of global ... 详细信息

关键词：国际工程工程科学经济发展人类社会

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性骚扰对工程学是一种威胁

科技纵览 2018年第11期 8-9页

作者： c.d.mote jr. Sheila E.Widnall Ed Lazowska Nicole Xu(插图) 美国国国家工程院麻省理工学院航空工程学院比尔及梅琳达·盖茨基金会华盛顿大学不详

美国国家科学院发布的一项报告表明,性侵犯问题得不到解决,受伤害的将不仅仅是受害者本人。几十年来,工程学界一直在努力提高女性在大学和行业中的比例,但进展缓慢。在美国,仅有21%的工程学士学位授予女性,而且见习工程师中只有11%为女... 详细信息

美国国家科学院发布的一项报告表明,性侵犯问题得不到解决,受伤害的将不仅仅是受害者本人。几十年来,工程学界一直在努力提高女性在大学和行业中的比例,但进展缓慢。在美国,仅有21%的工程学士学位授予女性,而且见习工程师中只有11%为女性。虽然这个问题很复杂,但我们必须认识到性骚扰是一个影响因素,这导致了工程学教育和工作的环境充满恶意,女性不敢踏足该领域半步。权威研究表明,20%-50%的女大学生在大学期间受到过性骚扰。

关键词：工程学骚扰女大学生女性科学院受害者工程师美国

A Pseudo-Stokes Mesh Motion Algorithm

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Advances in Applied Mathematics and Mechanics 2013年第2期5卷 194-211页

作者： Luciano Goncalves Noleto Manuel N.d.Barcelos jr. Antonio c.P.Brasil jr. Universidade de Brasılia Faculdade de TecnologiaDepartamento de Engenharia MecanicaLaboratorio de Energia e Ambiente.Asa Norte.Brasılia-DFBrasil70.910-900 Universidade de Brasılia no Gama.complexo de Educa¸c˜ao CulturaEsporte e Lazer.A rea Especial de Industria 1Setor LesteFaculdade Lote 1.Gama-DFBrasil72.444-210

This work presents a moving mesh methodology based on the solution of a pseudo flow *** mesh motion is modeled as a pseudo Stokes problem solved by an explicit finite element projection *** mesh quality requirements are satisfied by employing a null divergent velocity *** methodology is applied to triangular unstructured meshes and compared to well known approaches such as the ones based on diffusion and pseudo structural *** of the test cases is an airfoil with a fully meshed domain.A specific rotation velocity is imposed as the airfoil boundary *** other test is a set of two cylinders that move toward each other.A mesh quality criteria is employed to identify critically distorted elements and to evaluate the performance of each mesh motion *** results obtained for each test case show that the pseudo-flow methodology produces satisfactory meshes during the moving process.

关键词： Moving boundaries mesh motion strategy finite element projection methods

development of a 3d model for particle-wall collision and induced rotation and its influence on particle trajectories

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Particuology 2024年第11期94卷 211-228页

作者： cairen Miranda John Palmore jr. department of Mechanical Engineering Virginia TechBlacksburg24060VAUSA department of Mechanical Engineering University of WashingtonSeattle98195WAUSA

The present research focuses on improving the prediction of rotating particle *** particle-surface collision models do not accurately predict the particle rebound when taking rotation into *** data,such as the studies by Gorham and Kharaz(2000),Buck,Tang,Heinrich,deen and Kuipers(2017),and dong and Moys(2006)show that the Tsuji,Oshima and Morikawa(1985)model is inaccurate due to the incorrect tangential coefficient of restitution ***,Kuipers,Mohd Salleh,Stein,and Seville(2001)introduced a similar model to the work by Tsuji et al.(1985)which includes a tangential coefficient of restitution but is only in two dimensions and does not consider out of plane *** work re-derives the particle collision model from the impulse equations for binary collisions in 3d while considering rotating *** derived equations in this work compares well to experimental particle-surface impact *** implications of this model are seen by investigating erosion due to particle collision in a simple pipe *** is shown that Tsuji et al.(1985)over predicts the *** small differences in particle trajectories between the present model and the Tsuji et al.(1985)model will grow in complex flows with multiple close range particle impacts leading to inaccurate erosion predictions which will negatively impact the design of turbomachinery and pneumatic pipes.

关键词： Particle collisions cFd Rotation Three dimensional

Tracking Power System State Evolution with Maximum-correntropy-based Extended Kalman Filter

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Journal of Modern Power Systems and clean Energy 2020年第4期8卷 616-626页

作者： Julio A.d.Massignan João B.A.London jr. Vladimiro Miranda IEEE department of Electrical and computing Engineering School of Engineering of São CarlosUniversity of São PauloSão CarlosBrazil Faculty of Engineering University of Porto and INESC TECPortoPortugal

This paper develops a novel approach to track power system state evolution based on the maximum correntropy criterion,due to its robustness against non-Gaussian *** includes the temporal aspects on the estimation process within a maximum-correntropy-based extended Kalman filter(McEKF),which is able to deal with both nonlinear supervisory control and data acquisition(ScAdA)and phasor measurement unit(PMU)measurement *** representing the behavior of the state variables with a nonparametric model within the kernel density estimation,it is possible to include abrupt state transitions as part of the process noise with non-Gaussian ***,a novel strategy to update the size of Parzen windows in the kernel estimation is proposed to suppress the effects of suspect *** properly adjusting the kernel bandwidth,the proposed McEKF keeps its accuracy during sudden load changes and contingencies,or in the presence of bad *** with IEEE test systems and the Brazilian interconnected system are carried *** results show that the method deals with non-Gaussian noises in both the process and measurement,and provides accurate estimates of the system state under normal and abnormal conditions.

关键词： Tracking state estimation Kalman filter maximum correntropy power system Parzen window

Fabrication and characterization of cu–Zn–Sn shape memory alloys via an electrodeposition–annealing route

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International Journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1436-1449页

作者： Richard Espiritu Alberto Amorsolo jr. department of Mining Metallurgical and Materials Engineering University of the Philippines Diliman

cu–Zn–Sn shape memory alloys(SMAs)with an average composition of 56.0 at%,36.1 at%,and 7.9 at%for cu,Zn,and Sn,respectively,were successfully fabricated via an electrodeposition–annealing *** produced SMAs were assessed for shape memory response in terms of percent displacement(martensite phase recovery)by subjecting the ternary alloys to flame tests and subsequently characterizing them via differential scanning calorimetry(dSc),optical microscopy,scanning electron microscopy in conjunction with energy-dispersive spectroscopy(SEM-EdS),and X-ray diffraction(XRd)*** flame tests showed that the highest displacement was ca.93%,with average austenite and martensitic start transformation temperature of 225°c and 222°c,*** analysis revealed that the intermetallic phases responsible for the observed shape memory properties have substitutional Zn in the lattice occupied by cu and Sn,leading to the formation of cu(Zn,Sn)and cu6(Zn,Sn)5 *** formation of these variants was attributed to the faster interdiffusion of cu into Sn,driven by an activation energy of 34.82 kJ·mol^-*** cycles of repeated torching–annealing revealed an essentially constant shape memory response,suggesting that the fabricated SMAs were consistent and sufficiently reliable for their intended service application.

关键词： electrodeposition annealing intermetallics martensitic transformation shape memory alloy

Improved speciation of dissolved organic nitrogen in natural waters: amide hydrolysis with fluorescence derivatization

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Journal of Environmental Sciences 2008年第10期20卷 1273-1280页

作者： Ryan L.Fimmen Tamara d.Trouts daniel d.Richter jr. dharni Vasudevan School of Earth Sciences The Ohio State University 125 S.Oval MallColumbus OH 43210 USA.Nicholas School of the Environment and Earth Sciences Duke University Durham NC 27708 USA School of Earth Sciences The Ohio State University 125 S.Oval MallColumbus OH 43210 USA Nicholas School of the Environment and Earth Sciences Duke UniversityDurham NC 27708 USA. Nicholas School of the Environment and Earth Sciences Duke UniversityDurham NC 27708 USA.Department of Chemistry Bowdoin CollegeBrunswick ME 04011 USA

The objective of this study was to improve primary-amine nitrogen (1°-N) quantification in dissolved organic matter (dOM) originating from natural waters where inorganic forms of N, which may cause analytical interference, are commonly encountered. Efforts were targeted at elucidating organic-N structural criteria influencing the response of organic amines to known colorimetric and fluorescent reagents and exploring the use of divalent metal-assisted amide hydrolysis in combination with fluorescence analyse...

关键词： dissolved organic matter/nitrogen (dOM/dON) o-phthaldialdehyde fluorescamine ninhydrin amino acids amide hydrolysis peptides

crustal thickening in an active margin setting （Philippines）： The whys and the hows

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Episodes 2004年第4期27卷 260-264页

作者： c.B.dimalanta G.P.Yumul,jr. NationalInstituteofGeologicalSciences CollegeofScienceUniversityofthePhilippinesDilimanQuezonCityPhilippines1101.

A synthesis of crustal thickness estimates was made recently utilizing available field, geochemical, seismicity, shear wave velocity and gravity data in the Philippines. The results show that a significant portion of the Philippine archipelago is generally characterized by crust with a thickness of around 25 to 30 kilometers. However, two zones, which are made up of a thicker crust (from 30 to 65 km) have also been delineated. The Luzon central cordillera region is characterized by thick crust. Another belt of thickened crust is observed in the Bicol-Negros-Panay-central Mindanao region. This paper examines the interplay of tectonic and magmatic processes and their role in modifying Philippine arc crust. The processes, which could account for the observed crustal thicknesses, are presented. The contributions of magmatic arcs as compared to the contribution of the emplacement and accretion of ophiolite complexes to crustal thickness are also discussed.

关键词：地壳增厚活跃边缘环境剪力波速度菲律宾群岛地质构造

Examining the effect of speed, roadside features, and roadway geometry on crash experience along a rural corridor

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Journal of Modern Transportation 2014年第2期22卷 84-95页

作者： donald c. Watson jr. Ahmed Al-Kaisy Nathan d. Anderson 289 North Lake Lulu drive Winter Haven FL 33880 USA Western Transportation Institute Montana State University 213Cobleigh Hall Bozeman MT 59717 USA

This paper presents a current investigation into crash experience along a 15.7-mile rural corridor in southwest Montana with the aim of better understanding crash causal factors along the corridor. The study utilized ten years of crash data, geometric data, and observed freeflow speed data along the corridor. A systematic approach was used where every tenth of a mile was described in term of the crash experience, speed, alignment, and roadside features. Using bivariate and multivariate statistical anal-yses, the study investigated the crash experience along the corridor as well as some of the underlying relationships which could explain some of the crash causal factors. Results show a strong association between crash rates and horizontal curvatures even for flat curves that can be negotiated at speeds above the posted speed limit, per the highway design equations. Higher crash rates were also found to be associated with the difference between the observed free-flow speeds and the speed dictated by the curve radius or sight distance as per the design equations. Further, results strongly support the safety benefits of guardrails as evidenced by the lower crash rates and severities. The presence of fixed objects and the steepness of side slopes were also found to have an effect on crash rates and severities.

关键词： crashes Rural Analysis Alignment Speed Roadside