Modelling firm (re-)location choice in UrbanSim

Over the last decade, low economic growth rates resulted in intensified competition between nations, regions, and towns in trying to attract new firms and inhabitants. In particular, the establishment of new firms has become one of the most vital objectives of governments and public authorities all over Europe. To raise the attractiveness of a region, different instruments have been used: tax reductions, incentives for new establishments, as business destination promotion activities, supply of outstanding infrastructure and public services. On the one hand, this paper investigates effects of different possible options for cantonal and municipal authorities’ intent to attract firms: improvements in transport infrastructure, designation of new building zones, and last but not least tax reductions. These actions have been tested by simulating the decisions of existing firms. The parameters for these simulations have been estimated with a discrete choice model using data of the cantons St.Gallen and both Appenzell as well as Zurich. On the other hand, the paper aims to provide an approach to implement these models in UrbanSim. UrbanSim is a software-based simulation system for supporting planning and analysis of urban development, incorporating the interactions between land use, transportation, the economy, and the environment. At the moment, UrbanSim is adapted to an European context (see the according research project SustainCity, www.sustaincity.eu).

Dynamical typicality for initial states with a preset measurement statistics of several commuting observables

We consider all pure or mixed states of a quantum many-body system which exhibit the same, arbitrary but fixed measurement outcome statistics for several commuting observables. Taking those states as initial conditions, which are then propagated by the pertinent Schr\"odinger or von Neumann equation up to some later time point, and invoking a few additional, fairly weak and realistic assumptions, we show that most of them still entail very similar expectation values for any given observable. This so-called dynamical typicality property thus corroborates the widespread observation that a few macroscopic features are sufficient to ensure the reproducibility of experimental measurements despite many unknown and uncontrollable microscopic details of the system. We also discuss and exemplify the usefulness of our general analytical result as a powerful numerical tool

Ultra-fast X-ray particle velocimetry measurements within an abrasive water jet

Ultra-fast X-ray velocimetry measurements were taken to measure velocities and spatial positions of individual abrasive particles within the solid-liquid-gaseous three-phase flow of a high-pressure injection method-based abrasive water jet (AWJ). A synchrotron X-ray source provided sufficient photon flux to take double-frame images of the AWJ with an inter-frame time interval of 5μs. Abrasive particles with a Sauter mean diameter of 265.5μm were detected by a scintillator optically coupled to a gated image intensifier and a high-speed camera running at a frame rate of 11,250Hz. A commercially available particle tracking velocimetry software was used to process the acquired images and evaluate the spatial positions and velocities of abrasive particles as a function of water pressure and abrasive mass flow. The acquired data show a Gaussian radial distribution of abrasive particles within the AWJ and an almost uniform mean axial velocity, irrespective of water jet velocity and abrasive flow rates. These results are useful to validate theoretical models for the momentum/energy transfer in AWJ, to provide input for abrasion/erosion models, to further understand and advance the AWJ process, and to develop new process opportunities such as AWJ millin

Planning for the Future: A Land-Use and Transport Interaction Model for Switzerland

Spatial and transport planners, authorities, real estate developers, investors, re-locating residents and businesses have different questions related to space and transport. These questions may concern specific land parcels, or cover a much larger area such as a city, a region, or even a whole nation. Amongst others, these questions include: - How will our society respond to influences of global economy and political decisions (e.g. regarding demographics and firmographics)? - Which strategies will help authorities and politicians to reach their goals? - What are the spatial effects (and side-effects) of these decisions and demographic changes (e.g. spatial/social segregation, use of resources and infrastructure, climate impact)? To answer these questions, different scenarios have been simulated including all 3000 municipalities in Switzerland using the integrated transport and land use simulation tool FaLC (Facility Location Choice Simulation Tool). FaLC incorporates interactions between land use, transportation, economy and public policy and has been developed in a joint project between the Institute for Transport Planning and Systems (IVT) at ETH Zurich, regioConcept (Switzerland) and ESMO (Slovakia). The models in FaLC focus on the effects of changing infrastructure supply, political decisions, and economic conditions on the spatial behaviour (location and relocation choices, transport flows) of persons (places of residence, work, leisure and shopping), firms (domicile, branches) and goods (freights, wholesale, retail, cash flow). In FaLC, persons move (or stay) in a certain space divided into a number of subareas (locations), comparable to a chess board. The agents' movement includes the daily commuters between home, work and leisure, as well as long-term decisions such as; where they live, work and generally spend their spare time. The first prototype of FaLC is already in operation and ready to create future scenarios. The implemented case study for Switzerland focusses basically on three scenarios: - Effects of road network modification - Effects of company taxes reduction - Effects of land regulation modification This paper shows the effects and side-effects of these assumed spatial interventions. Additionally, it discusses some problems of the chosen micro-simulation approach (e.g. data availability, white noise, choice of subsets)

Arquitectura de decisiones

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The Enigmatic Young Object: Walker 90/V590 Monocerotis

We assess the evolutionary status of the intriguing object Walker 90/V590 Mon, which is located about 20 arcminutes northwest of the Cone Nebula near the center of the open cluster NGC 2264. This object, according to its most recent optical spectral type determination (B7), which we confirmed, is at least 3 magnitudes too faint in V for the cluster distance, but it shows the classical signs of a young pre-main sequence object, such as highly variable Halpha emission, Mg II emission, IR excess, UV continuum, and optical variability. We analyzed a collection of archival and original data on Walker 90, covering 45 years including photometry, imaging, and spectroscopic data ranging from ultraviolet to near-infrared wavelengths. According to star formation processes, it is expected that, as this object clears its primordial surroundings, it should become optically brighter, show a weakening of its IR excess and present decreasing line emissions. This behavior is supported by our observations and analysis, but timescales are expected to be longer than the one observed here. Based on photometric data secured in 2007, we find Walker 90 at its brightest recorded optical magnitude. We document an evolution in spectral type over the past five decades (from A2/A3 to currently B7 and as early as B4), along with a decrease in the near-infrared K fluxes. From near-infrared images secured in 2004, Walker 90 appears as a point source placing an upper limit of 0.1 arcsec for its diameter. We conclude that many observational features are explained if W90 is a flared disk system, surrounded by an inclined optically thick accretion disk.Comment: 13 pages, 19 figure

Excitations in the field-induced quantum spin liquid state of α-RuCl3

The celebrated Kitaev quantum spin liquid (QSL) is the paradigmatic example of a topological magnet with emergent excitations in the form of Majorana Fermions and gauge fluxes. Upon breaking of time-reversal symmetry, for example in an external magnetic field, these fractionalized quasiparticles acquire non-Abelian exchange statistics, an important ingredient for topologically protected quantum computing. Consequently, there has been enormous interest in exploring possible material realizations of Kitaev physics and several candidate materials have been put forward, recently including α-RuCl3. In the absence of a magnetic field this material orders at a finite temperature and exhibits low-energy spin wave excitations. However, at moderate energies, the spectrum is unconventional and the response shows evidence for fractional excitations. Here we use time-of-flight inelastic neutron scattering to show that the application of a sufficiently large magnetic field in the honeycomb plane suppresses the magnetic order and the spin waves, leaving a gapped continuum spectrum of magnetic excitations. Our comparisons of the scattering to the available calculations for a Kitaev QSL show that they are consistent with the magnetic field induced QSL phase.The work at ORNL’s Spallation Neutron Source and the High Flux Isotope Reactor was supported by the United States Department of Energy (US-DOE), Office of Science - Basic Energy Sciences (BES), Scientific User Facilities Division. Part of the research was supported by the US-DOE, Office of Science - BES, Materials Sciences and Engineering Division (P.K., C.A.B. and J-Q.Y.). D.M. and P.K. acknowledge support from the Gordon and Betty Moore Foundation’s EPiQS Initiative through Grant GBMF4416. The work at Dresden was in part supported by DFG grant SFB 1143 (J.K. and R.M.). J.K. is supported by the Marie Curie Programme under EC Grant agreements No.703697

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13