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中国人体科学 1992年第4期2卷 187-191,186页

作者： nash,cb 能哲宏

Curved Space-Time at the Planck Scale

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 167-179页

作者： Lewis nash Marietta GA USA

This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the metric tensor, is considered to be made up of a dynamic lattice of extremely small, localized fields that form a perfectly elastic Lorentz symmetric space-time at the global (macroscopic) scale. This theoretical model of space-time at the Planck scale leads to a somewhat surprising result in which matter waves in curved space-time radiate thermal gravitational energy, as well as an equally intriguing relationship for the anomalous dispersion of light in a gravitational field.

关键词： Schwarzschild Space-Time Continuum Mechanics Planck Lattice Gravitational Radiation

The GBR Hypothesis Revisited

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 800-809页

作者： Lewis nash Marrietta GA USA

The radical hypothesis concerning the physics of gravitational black-body radiation is placed on a more solid statistical mechanics foundation in this study. As the concepts and formalism in the former presentation are only partially developed and furthermore, suffer from an unfortunate misstep regarding Hawking radiation and the hypothetical gravitational black-body temperature of a parcel or distribution of energy;this paper aims to fill in some of the theoretical gaps in the derivation of the Planck radiation formula for gravity (or non-Euclidean space-time), and there by provide a more complete and transparent quantum theory of thermal gravitational radiation.

关键词： Gravitational Black Body Gravitons Thermal Gravitational Radiation Spiral Galaxy Rotation Curves

Publisher’s Erratum to:Metamaterial-based graphene thermal emitter

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Nano Research 2024年第6期17卷 5753-5753页

作者： Cheng Shi Nathan H.Mahlmeister Isaac J.Luxmoore Geoffrey R.nash College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeterEX44QFUK

The article"Metamaterial-based graphene thermal emitter",written by Cheng Shi,Nathan ***,***,and Geoffrey ***,was originally published electronically on the publisher’s internet portal(currently SpringerLink)on December 6th 2017 without open *** the author(s)’decision to opt for Open Choice the copyright of the article changed in February 2018 to©The Author(s)2018 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License(http://***/licenses/by/4.0/),which permits use,duplication,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons license and indicate if changes were *** original article has been corrected.

关键词： emitter license creative

High-resolution flood modeling of urban areas using MSN_Flood

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Water Science and Engineering 2017年第3期10卷 175-183页

作者： Michael Hartnett Stephen nash Department of Civil Engineering National University of IrelandGalwayIreland

Although existing hydraulic models have been used to simulate and predict urban flooding, most of these models are inadequate due to the high spatial resolution required to simulate flows in urban floodplains. Nesting high-resolution subdomains within coarser-resolution models is an efficient solution for enabling simultaneous calculation of flooding due to tides, surges, and high river flows. MSN_Flood has been developed to incorporate moving boundaries around nested domains, permitting alternate flooding and drying along the boundary and in the interior of the domain. Ghost cells adjacent to open boundary cells convert open boundaries, in effect, into internal boundaries. The moving boundary may be multi-segmented and non-continuous, with recirculating flow across the boundary. When combined with a bespoke adaptive interpolation scheme, this approach facilitates a dynamic internal boundary. Based on an alternating-direction semi-implicit finite difference scheme,MSN_Flood was used to hindcast a major flood event in Cork City resulting from the combined pressures of fluvial, tidal, and storm surge processes. The results show that the model is computationally efficient, as the 2-m high-resolution nest is used only in the urban flooded ***, lower-resolution nests are used. The results also show that the model is highly accurate when compared with measured data. The model is capable of incorporating nested sub-domains when the nested boundary is multi-segmented and highly complex with lateral gradients of elevation and velocities. This is a major benefit when modelling urban floodplains at very high resolution.

关键词： Multi-scale nesting Surge-fluvial flooding Urban flooding Multi-segmented boundary Moving boundary

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

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

SYNTHESIS　OF　TETRAMETHYL　SALVIANOLIC　ACID　F　AND　TRIMETHYL　PRZEWALSKINIC　ACID　A

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Chinese Chemical Letters 1996年第5期7卷 427-430页

作者： Al, cb Li, LN CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Abstract: Salvianolic acid F (1a) and przewalskinic add A(2a) are phenolic acids isolated from the traditional and herbal Chinese medicines Salvia miltiorrhiza (1) and S. przewalskii (2). The chemical structures of these two compounds represent the main carbon skeletons of the biologically active depsides salvianolicacid A and B isolated from S. miltionhiza (3.4). The present paper reports the synthesis of the methyl ether protected phenolic acids. tetramethyl salvianolic acid F(1b) and trimethyl prsewalskinic acid A(2b).

关键词： ACID TRIMETHYL TETRAMETHYL PRZEWALSKINIC SALVIANOLIC SYNTHESIS AND OF

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

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S1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