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An integrated measurement and modeling methodology for estuarine water quality management

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Water Science and Engineering 2015年第1期8卷 9-19页

作者： Michael Hartnett stephen nash Department of Civil Engineering National University of Ireland

This paper describes research undertaken by the authors to develop an integrated measurement and modeling methodology for water quality management of estuaries. The approach developed utilizes modeling and measurement results in a synergistic manner. Modeling results were initially used to inform the field campaign of appropriate sampling locations and times, and field data were used to develop accurate models. Remote sensing techniques were used to capture data for both model development and model validation. Field surveys were undertaken to provide model initial conditions through data assimilation and determine nutrient fluxes into the model domain. From field data, salinity re- lationships were developed with various water quality parameters, and relationships between chlorophyll a concentrations, transparency, and light attenuation were also developed. These relationships proved to be invaluable in model development, particularly in modeling the growth and decay of chlorophyll a. Cork Harbour, an estuary that regularly experiences summer algal blooms due to anthropogenic sources of nutrients, was used as a case study to develop the methodology. The integration of remote sensing, conventional fieldwork, and modeling is one of the novel aspects of this research and the approach developed has widespread applicability.

关键词： Estuarine modeling Hydrodynamics Water quality management Nutrients Phytoplankton Field measurements Remote sensing

Observation and modeling of tide- and wind-induced surface currents in Galway Bay

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Water Science and Engineering 2015年第4期8卷 345-352页

作者： Lei Ren stephen nash Michael Hartnett Department of Civil Engineering College of Engineering and Informatics National University of Ireland

A high-frequency radar system has been deployed in Galway Bay, a semi-enclosed bay on the west coast of Ireland. The system provides surface currents with fine spatial resolution every hour. Prior to its use for model validation, the accuracy of the radar data was verified through comparison with measurements from acoustic Doppler current profilers （ADCPs） and a good correlation between time series of surface current speeds and directions obtained from radar data and ADCP data. Since Galway Bay is located on the coast of the Atlantic Ocean, it is subject to relatively windy conditions, and surface currents are therefore strongly wind-driven. With a view to assimilating the radar data for forecasting purposes, a three-dimensional numerical model of Galway Bay, the Environmental Fluid Dynamics Code （EFDC）, was developed based on a terrain-following vertical （sigma） coordinate system. This study shows that the performance and accuracy of the numerical model, particularly with regard to tide- and wind-induced surface currents, are sensitive to the vertical layer structure. Results of five models with different layer structures are presented and compared with radar measurements. A variable vertical structure with thin layers at the bottom and the surface and thicker layers in the middle of the water column was found to be the optimal layer structure for reproduction of tideand wind-induced surface currents. This structure ensures that wind shear can properly propagate from the surface layer to the sub-surface layers, thereby ensuring that wind forcing is not overdamped by tidal forcing. The vertical layer structure affects not only the velocities at the surface layer but also the velocities further down in the water column.

关键词： Wind-induced surface current Vertical layer structure High-frequency radar Coastal ocean dynamics application radar Environmental fluid dynamicscode Galway Bay

Truncated Newton-Based Multigrid Algorithm for Centroidal Voronoi Diagram Calculation

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Numerical Mathematics(Theory,Methods and Applications) 2012年第2期5卷 242-259页

作者： Zichao Di Maria Emelianenko stephen nash Department of Mathematical Sciences George Mason UniversityFairfaxVA 22030USA. Systems Engineering and Operations Research Department George Mason UniversityFairfaxVA 22030USA

In a variety of modern applications there arises a need to tessellate the domain into representative regions,called Voronoi cells.A particular type of such tessellations,called centroidal Voronoi tessellations or CVTs,are in big demand due to their optimality properties important for many *** availability of fast and reliable algorithms for their construction is crucial for their successful use in practical *** paper introduces a new multigrid algorithm for constructing CVTs that is based on the MG/Opt algorithm that was originally designed to solve large nonlinear optimization *** convergence of the new method and its speedup comparing to existing techniques are demonstrated for linear and nonlinear densities for several 1d and 2d problems,and O(k)complexity estimation is provided for a problem with k generators.

关键词： Centroidal Voronoi tessellation optimal quantization truncated Newton method Lloyd’s algorithm multilevel method uniform convergence

Ancient DNA of the pygmy marmoset type specimen Cebuella pygmaea(Spix,1823)resolves a taxonomic conundrum

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Zoological Research 2021年第6期42卷 761-771页

作者： Jean P.Boubli Mareike C.Janiak Leila M.Porter Stella de la Torre Liliana Cortes-Ortiz Maria N.Fda Silva Anthony B.Rylands stephen nash Fabricio Bertuol Hazel Byrne Felipe E.Silva Fabio Rohe Dorien de Vries Robin M.D.Beck Irune Ruiz-Gartzia Lukas F.K.Kuderna Tomas Marques-Bonet Tomas Hrbek Izeni P.Farias Anneke Hvan Heteren Christian Roos School of Science Engineering&EnvironmentUniversity of SalfordSalford M54WTUK Instituto Nacional de Pesquisas da Amazonia ManausAmazonas 69060-001Brazil Department of Anthropology Northern Illinois UniversityDeKalbIL 60115-2828USA College of Biological and Environmental Sciences Universidad San Francisco de QuitoQuito 170901Ecuador Department of Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109USA Re:wild AustinTX 78767USA Laboratorio de Evolução e Genética Animal Universidade Federal do AmazonasManausAmazonas 69080-900Brazil Department of Anthropology University of UtahSalt Lake CityUT 84112USA Research Group on Primate Biology and Conservation MamirauaInstitute for Sustainable DevelopmentTeféAmazonas 69553-225Brazil Experimental and Health Sciences Department(DCEXS) Institut de Biologia EvolutivaUniversitat Pompeu Fabra-CSICBarcelona 08002Spain Department of Biology Trinity UniversitySan AntonioTX 78212USA Bavarian State Collection of Zoology Zoologische Staatssammlung MünchenStaatliche Naturkundliche Sammlungen Bayerns81247 MunichGermany GeoBio-Center Ludwig-Maximilians-Universitat München80333 MunichGermany Department Biologie II Ludwig-Maximilians-Universitat München82152 MunichGermany Gene Bank of Primates and Primate Genetics Laboratory German Primate CenterLeibniz Institute for Primate Research37077 GottingenGermany

The pygmy marmoset,the smallest of the anthropoid primates,has a broad distribution in Western *** studies using molecular and morphological data have identified two distinct species separated by the Napo and Solimoes-Amazonas ***,reconciling this new biological evidence with current taxonomy,i.e.,two subspecies,Cebuella pygmaea pygmaea(Spix,1823)and Cebuella pygmaea niveiventris(Lönnberg,1940),was problematic given the uncertainty as to whether Spix’s pygmy marmoset(Cebuella pygmaea pygmaea)was collected north or south of the Napo and Solimoes-Amazonas rivers,making it unclear to which of the two newly revealed species the name pygmaea would ***,we present the first molecular data from Spix’s type specimen of Cebuella pygmaea,as well as novel mitochondrial genomes from modern pygmy marmosets sampled near the type locality(Tabatinga)on both sides of the *** these data,we can confirm the correct names of the two species identified,i.e.,*** for animals north of the Napo and Solimoes-Amazonas rivers and *** for animals south of these two *** analyses of the novel genetic data placed into the context of cytochrome b gene sequences from across the range of pygmy marmosets further led us to reevaluate the geographical distribution for the two Cebuella *** dated the split of these two species to 2.54 million years *** discuss additional,more recent,subdivisions within each lineage,as well as potential contact zones between the two species in the headwaters of these rivers.

关键词： Historic DNA DNA taxonomy Pygmy marmoset Cebuella pygmaea C.niveiventris Amazon Type specimen

Controlling the properties of surface acoustic waves using graphene

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Nano Research 2016年第3期9卷 685-691页

作者： Lokeshwar Bandhu Geoffrey R. nash College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK

Surface acoustic waves （SAWs） are elastic waves that propagate on the surface of a solid, much like waves on the ocean, with SAW devices used widely in communication and sensing. The ability to dynamically control the properties of SAWs would allow the creation of devices with improved performance or new functionality. However, so far it has proved extremely difficult to develop a practical way of achieving this control. In this paper we demonstrate voltage control of SAWs in a hybrid graphene-lithium niobate device. The velocity shift of the SAWs was measured as the conductivity of the graphene was modulated using an ion-gel gate, with a 0.1% velocity shift achieved for a bias of approximately 1 V. This velocity shift is comparable to that previously achieved in much more complicated hybrid semiconductor devices, and optimization of this approach could therefore lead to a practical, cost-effective voltage-controlled velocity shifter. In addition, the piezoelectric fields associated with the SAW can also be used to trap and transport the charge carriers within the graphene. Uniquely to graphene, we show that the acoustoelectric current in the same device can be reversed, and switched off, using the gate voltage.

关键词： graphene sensors surface acoustic wave charge transport

The Role of Big Data and Machine Learning in the Integration and Implementation of Historical,Current,and Continuously Gathered Earth Data

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 56-58页

作者： Susan Smith nash American Association of Petroleum Geologists TulsaOklahoma 74119

We are faced with more challenges than ever with respect to the amount,variety,and sheer volume of earth *** only do we have data of many different ages and origins,we also have a wide variety of data,much of which has just been recently digitized,or is in a format that can cannot easily be integrated into algorithms,georeferenced data.

关键词： Big Data analytics machine learning deep learning artificial intelligence

Exercise in the management of metabolic dysfunction-associated fatty liver disease-is more the answer, or is it just one piece of the puzzle?

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Hepatobiliary Surgery and Nutrition 2024年第2期13卷 329-332页

作者： Emily nash Ken Liu AW Morrow Gastroenterology and Liver Centre Royal Prince Alfred HospitalSydneyNSWAustralia Faculty of Medicine and Health University of SydneySydneyNSWAustralia Liver Injury and Cancer Program Centenary InstituteSydneyNSWAustralia

Metabolic dysfunction-associated fatty liver disease(MAFLD)is the liver manifestation of metabolic syndrome,a rapidly growing clinical and public health issue mirrored by epidemic rates of obesity,type 2 diabetes mellitus,hypertension and cardiovascular disease(CVD).Besides MAFLD,nomenclature used to capture fatty liver disease not primarily due to alcohol excess include non-alcoholic fatty liver disease(NAFLD)and metabolic dysfunction-associated steatotic liver disease(MASLD).Regardless of the terminology used,these diagnoses describe the most common cause of chronic liver disease ***,MAFLD is poised to become the leading cause of hepatocellular carcinoma(HCC)and end-stage liver disease requiring liver transplantation around the world(1,2).In addition to this,CVD and extra-hepatic cancers are the two main causes of death in the MAFLD ***,MAFLD poses a severe clinical burden which is projected to worsen in the future and intervention is urgently needed.

关键词： Exercise metabolic dysfunction-associated liver disease(MAFLD) diet obesity weight loss

Enthalpies of formation of compounds in Al-Ni-Y system

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中国有色金属学会会刊：英文版 2002年第4期12卷 754-758页

作者： P.nash O.Kleppa ThermalProcessingTechnologyCenter IllinoisInstituteofTechnology10W32ndStChicago.IL60616USA JamesFrankInstitute UniversityofChicago5640SellisAveChicago.IL60637USA

The enthalpies of formation of the ternary compounds Al 4NiY, Al 2NiY, Al 2Ni 6Y 3, Al 16 Ni 3Y, AlNiY, Al 3Ni 2Y, AlNi 8Y 3, Al 7Ni 3Y 2, and of the binary compounds Al 2Y containing nickel and Ni 5Y containing aluminum have been determined by high temperature reaction calorimetry. The enthalpy values measured are compared to previously published results where available as well as extended Miedema model predictions. The melting points of the compounds were determined by DTA and X ray diffraction was used to confirm the crystal structures of the compounds. The enthalpies of formation of the ternary compounds show a maximum along the 50%Al (mole fraction) section. The ternary compounds appear along lines of constant yttrium content consistent with binary compound solubility extensions.

关键词： Al-Ni-Y合金组分生成焓

Surface Microcracks and Relief Caused by Lamella Sliding during High Temperature Tension of Titanium Alloy with Lamella Structure

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Journal of Materials Science & Technology 2006年第4期22卷 470-472页

作者： Feng XU Geping LI Mesut VARLIOGLU Philip nash Rui YANG Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Illinois Institute Technology Thermal Processing Technology Center Chicago IL USA

Lateral surface near the fracture of before and after oxide film removing tensile sample was examined by scanning electron The relationship between surface morphology and microscopy （SEM） microstructure was established. The results show that the microcracks are caused by brittleness rupture of surface oxide films due to α lamellas sliding along α lamella boundaries. And the sliding of aligned α lamellas bring not only microcrack formation but also the raise of colony relative to prior sample surface. A slip model, which depicts the relationship between surface morphology and microstructure, was brought forward to analyze the observation.

关键词： Titanium alloy Sliding Crack