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出口FTS所需的证明

现代制造 2019年第24期 42-42页

作者： werner varro 不详

任何出口无人驾驶运输系统(FTS)的人都必须提供各种证明,TUEV Sued以一家领先的机器人企业和一个完全集成的送料器为例进行了演示。

关键词：无人驾驶运输系统送料器

Exact orbital-free kinetic energy functional for general many-electron systems

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Frontiers of physics 2020年第2期15卷 87-92页

作者： Thomas Pope werner Hofer School of Natural and Environmental Sciences Newcastle UniversityNewcastle NE17RUUnited Kingdom School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China

The exact form of the kinetic energy functional has remained elusive in orbital-free models of density functional theory(DFT).This has been the main stumbling block for the development of a general-purpose framework on this ***,we show that on the basis of a two-density model,which represents many-electron systems by mass density and spin density components,we can derive the exact form of such a *** exact functional is shown to contain previously suggested functionals to some extent,with the notable exception of the Thomas-Fermi kinetic energy functional.

关键词： condensed matter density functional theory(DFT) extended electrons

Solving the dark-matter problem through dynamic interactions

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Frontiers of physics 2015年第6期10卷 1-5页

作者： werner A. Hofer School of Mathematics and Statistics Newcastle University Newcastle upon Tyne NE1 7R U UK

Owing to the renewed interest in dark matter after the upgrade of the large hadron collider and its dedication to dark-matter research, it is timely to reassess the whole problem. Considering dark matter is one way to reconcile the discrepancy between the velocity of matter in the outer regions of galaxies and the observed galactic mass. Thus far, no credible candidate for dark matter has been identified. Here, we develop a model accounting for observations by rotations and interactions between rotating objects analogous to magnetic fields and interactions with moving charges. The magnitude of these fields is described by a fundamental constant on the order of 10^-41kg^-1. The same interactions can be observed in the solar system, where they lead to small changes in planetary orbits.

关键词： galactic rotation curves dark matter solar system perihelion of Mercury nodes of Venus

Uncertainty relations for general phase spaces

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Frontiers of physics 2016年第3期11卷 51-60页

作者： Reinhard F. werner Institut fiir Theoretische Physik Leibniz Universitiit Hannover Germany

We describe a setup for obtain!ing uncertainty relations for arbitrary pairs of observables related by a Fourier transform. The physical examples discussed here are the standard position and momentum, number and angle, finite qudit systems, and strings of qubits for quantum information applications. The uncertainty relations allow for an arbitrary choice of metric for the outcome distance, and the choice of an exponent distinguishing, e.g., absolute and root mean square deviations. The emphasis of this article is on developing a unified treatment, in which one observable takes on values in an arbitrary locally compact Abelian group and the other in the dual group. In all cases, the phase space symmetry implies the eciuality of measurement and preparation uncertainty bounds. There is also a straightforward method for determining the optimal bounds.

关键词： uncertainty relations phase space measurement uncertainty

A two-density approach to the general many-body problem and a proof of principle for small atoms and molecules

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Frontiers of physics 2019年第2期14卷 89-96页

作者： Thomas Pope werner Hofer School of Natural and Environmental Sciences Newcastle UniversityNewcastle NE1 7RUUnited Kingdom Institute of Physics & University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China

An extended electron model fully recovers many of the experimental results of quantum mechanics while it avoids many of the pitfalls and remains generally free of paradoxes. The formulation of the manybody electronic problem here resembles the Kohn Sham formulation of standard density functional theory. However, rather than referring electronic properties to a large set of single electron orbitals, the extended electron model uses only mass density and field components, leading to a substantial increase in computational efficiency. To date, the Hohenberg-Kohn theorems have not been proved for a model of this type, nor has a universal energy functional been presented. In this paper, we address these problems and show that the Hohenberg Kohn theorems do also hold for a density model of this type. We then present a proof^of^concept practical implementation of this method and show that it reproduces the accuracy of more widely used methods on a test-set of small atomic systems, thus paving the way for the development of fast, efficient and accurate codes on this basis.

关键词： many-body condensed matter Hartree-Fock density functional theory extended electrons

Single-mode and tunable VCSELs in the near-to mid-infrared Invited Paper

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Chinese Optics Letters 2008年第10期6卷 743-747页

作者： Markus-Christian Amann werner Hofmann Walter Schottky Institut Technische Universitt MnchenD-85748 GarchingGermany

Single-mode, long-wavelength vertical-cavity surface-emitting lasers （VCSELs） in the near- to mid-infrared covering the wavelength range from 1.3 to 2.3 μm are presented. This wide spectral emission range opens applications in gas sensing and optical interconnects. All these lasers are monolithically grown in the InGaAlAs-InP material system utilizing a buried tunnel junction （BTJ） as current aperture. Fabricated with a novel high-speed design with reduced parasitics, bandwidths in excess of 10 GHz at 1.3 and 1.55 μm have been achieved. Therefore, the coarse wavelength division multiplexing （CWDM） wavelength range of 1.3 to 1.6 μm at 10 Gb/s can be accomplished with one technology. Error-free data-transmission at 10 Gb/s over a fiber link of 20 km is demonstrated. One-dimensional arrays have been fabricated with emission wavelengths addressable by current tuning. Micro-electro-mechanical system （MEMS） tunable devices provide an extended tuning range in excess of 50 nm with high spectral purity. All these devices feature continuous-wave （CW） operation with typical single-mode output powers exceeding 1 mW. The operation voltage is around 1 - 1.5 V and power consumption is as low as 10 - 20 mW. Furthermore, we have also developed VCSELs based on GaSb, targeting functionality of tunable diode laser spectroscopy （TDLS） applying a 1.84-μm VCSEL. at the wavelength range from 2.3 to 3.0 μm. The systems is shown by presenting a laser hygrometer

关键词： mode VCSEL Single-mode and tunable VCSELs in the near-to mid-infrared Invited Paper

Heisenberg, uncertainty, and the scanning tunneling microscope

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Frontiers of physics 2012年第2期7卷 218-222页

作者： werner A. Hofer (1) 1. Department of Physics University of Liverpool L69 3BX Liverpool UK

We show by a statistical analysis of high-resolution scanning tunneling microscopy （STM） exper- iments, that the interpretation of the density of electron charge as a statistical quantity leads to a conflict with the Heisenberg uncertainty principle. Given the precision in these experiments we find that the uncertainty principle would be violated by close to two orders of magnitude, if this interpretation were correct. We are thus forced to conclude that the density of electron charge is a physically real, i.e., in principle precisely measurable quantity.

关键词： scanning tunneling microscope electron charge density functional theory uncertaintyrelations

Spin in the extended electron model

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Frontiers of physics 2017年第3期12卷 81-85页

作者： Thomas Pope werner Hofer School of Chemistry Newcastle University Newcastle NE1 7RU UK

It has been found that a model of extended electrons is more suited to describe theoretical simula- tions and experimental results obtained via scanning tunnelling microscopes, but while the dynamic properties are easily incorporated, magnetic properties, and in particular electron spin properties pose a problem due to their conceived isotropy in the absence of measurement. The spin of an electron reacts with a magnetic field and thus has the properties of a vector. However, electron spin is also isotropic, suggesting that it does not have the properties of a vector. This central conflict in the de- scription of an electron＇s spin, we believe, is the root of many of the paradoxical properties measured and postulated for quantum spin particles. Exploiting a model in which the electron spin is described consistently in real three-dimensional space - an extended electron model - we demonstrate that spin may be described by a vector and still maintain its isotropy. In this framework, we re-evaluate the Stern-Gerlach experiments, the Einstein-Podolsky-Rosen experiments, and the effect of consecutive ts and find in all cases a fairly intuitive explanation.

关键词： spin extended electron model geometric algebra Stern-Gerlach experiment Einstein-Podolsky-Rosen magnetism

Case studies of high-sensitivity monitoring of natural and engineered slopes

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第4期7卷 379-384页

作者： werner Lienhart Graz University of Technology

High-sensitivity monitoring solutions are crucial for early warning systems of earth structures. In this paper, we discuss the design and implementation of such systems for natural and engineered slopes using two case studies. At the Gradenbach Observatory, one key element of the monitoring system is a large fiber optic strain rosette embedded in the slope. We demonstrate that the strain rosette can depict landslide deformations much earlier than geodetic sensors like GPS or total stations and is therefore well suitable for an early warning system. In a second application we report the construction of a reinforced earth structure using geogrids. A distributed fiber optic measurement system was installed to measure the current operating grade of the geogrids within the earth structure. About 2 km of Brillouin sensing cables were installed in the project area. It is demonstrated that the developed monitoring system is well suited for assessing the current state of health of reinforced earth structures.

关键词： Structural health monitoring Fiber optic sensors Brillouin optical frequency domain analyzer(BOFDA) SOFO sensors Reinforced eart