Traffic and the Economy : How to utilize open traffic data in economic analysis

This thesis studies the interaction of passenger car traffic and the economy. Finnish law requires a cost benefit -calculation for government-financed infrastructure investments. For this reason, the economic models and literature to model the interactions of infrastructure and the economy has been in high demand in Finland. The literature review in this thesis looks at traffic economics through the dynamics of congestion, the value of time savings and methods to utilize these valuations in the form of road toll schemes. The literature review also looks at the housing and labour market out-comes from infrastructure investments. To finish off the literature review, there’s a compre-hensive study of literature around the data used in this study and how it has been utilized. This literature review generates an understanding of the past and current affairs of how traffic data is used in analysing the economy and what kind of avenues exist to evaluate the impact of transportation infrastructure. These are mainly: population, labour market out-comes, housing market prices and travel demand. The analysis seeks to validate the use of traffic data as a split dataset between work and leisure times. The literature shows a clear difference in time values and behavior in different types of travel demand. The raw data from Finnish Traffic and Infrastructure Agency is vali-dated and analyzed with simple OLS regressions with different economic variables. There are distinct differences in work and leisure-time traffic. The split also makes models perform a lot better and when combined they make the models perform very well. However, as the analysis studies all the municipalities along the E18, the analysis ends up showing the differences between municipalities in stead of causal effects of the E18 to local municipalities during the study period. The analysis finds multiple ways to use and develop the model and how a single piece of infrastructure can be modeled better. These better models can then be utilized in analyzing the efficacy of infrastructure investments with higher precision

Holographic Superfluids and Solitons

Superfluidity is perhaps one of the most remarkable observed macroscopic quantum effect. Superfluidity appears when a macroscopic number of particles occupies a single quantum state. Using modern experimental techniques one dark solitons) and vortices. There is a large literature on theoretical work studying the properties of such solitons using semiclassical methods. This thesis describes an alternative method for the study of superfluid solitons. The method used here is a holographic duality between a class of quantum field theories and gravitational theories. The classical limit of the gravitational system maps into a strong coupling limit of the quantum field theory. We use a holographic model of superfluidity to study solitons in these systems. One particularly appealing feature of this technique is that it allows us to take into account finite temperature effects in a large range of temperatures.Supraneste on makroskooppinen kvanttimekaaninen systeemi, jossa suuri määrä hiukkasia asettuu samalle perustilalle. Tätä perustilaa kuvaa kvanttimekaaninen aaltofunktio, joka kertoo hiukkasten paikan todennäköisyysjakaumasta. Modernein kokeellisin menetelmin supranesteen aaltofuntiota voidaan muokata luoden siihen esimerkiksi seinämäisiä rakenteita tai pyörteitä, joita molempia kutsutaan solitoneiksi. Kiinteän olomuodon fysiikassa kyseisiä solitoneja tutkitaan pääosin käyttäen sellaisia approksimaatioita, jotka toimivat heikosti vuorovaikuttavissa kvanttikenttäteorioissa. Tämä väitöskirja esittelee tutkimusta, jossa supranesteissä olevia solitoneja tutkitaan eräissä vahvasti vuorovaikuttavissa teorioissa. Vahvasti vuorovaikuttavien kvanttikenttäteorioiden tutkimisen mahdollistaa eräs holografinen vastaavuus kvanttikenttäteorioiden ja gravitaatioteorioiden välillä. Vahvojen vuorovaikutusten lisäksi käytetty metodi sallii äärellisen lämpötilan efektien tutkimisen laajalla lämpötilaskaalalla

Integration of Product Data Management system

Yritysten tietojärjestelmät koostuvat useista pienemmistä kokonaisuuksista, joiden toiminta on saatettava yhtenäiseksi siten, että se tukee yrityksen liiketoimintamallia mahdollisimman luonnollisesti. Tämän toteuttamiseksi on eri sovellukset saatettava keskustelemaan keskenään hallitusti ja varmasti. Sovellusten integrointi on yleinen ongelma ja näihin liittyvät projektit pitkiä sekä vaativia. Ratkaisuksi on tarjottu erilaisia arkkitehtuureja kuten point-to-point, enterprise application integration (EAI) ja enterprise service bus (ESB). Näistä ESB on nykyään yleisimmin käytössä oleva malli. ESB:n toteuttamiseksi on kehitetty erilaisia väliohjelmia, jos jotka kokoavat yhteen integrointia tukevia toimintoja. Sovellusten välinen tiedonvaihto keskittyy viestitykseen, jossa sovellusten ohjelmointirajapintojen kautta tehdään pyyntöjä toiminnoista. Toiminnot kuvataan palveluina. Yleinen viestimuoto on rakenteiset dokumentit, käytännössä XML. SOAP:n avulla voidaan pyynnöt kuvata myös XML muotoisina, ja vastaus saadaan niin ikään SOAP:n avulla hyötykuorman sisältyessä viestin body osioon. Tuotetiedonhallintajärjestelmän (PDM) tarkoituksena on tarjota yritykselle sijainti eri tuotteisiin liittyvälle tiedolle. Tämän työn puitteissa tuote on sähkömoottori, ja PDM sisältää tiedot kaikista tehdyistä moottoreista, niiden sisältämistä osista sekä niihin liittyvistä mekaanisista suunnittelukuvista. PDM:ään voidaan myös kuvata valintasäännöt tuotekonfiguraattorille, jolloin asiakkaan haluaman tuotteen rakenne voidaan tehdä automaattisesti ilman, että järjestelmä sisältäisi valmiiksi juuri kyseisenlaisen tuotteen. Tässä työssä on tavoitteena saada yrityksen uusi PDM integroitua alihankkijan järjestelmään. Myös uuden toiminnanohjausjärjestelmän (engl. Enterprise Resource Planning, ERP) integrointia sivutaan integraation suunnittelumallien (engl. Enterprise Integration Patterns) avulla. Esityönä selvitetään miten tuoterakenne saadaan määriteltyä uuteen PDM:n, ja miten vanhasta PDM:stä saadaan tuotua data uuteen järjestelmään. Tämän lisäksi suunnittelumallien avulla hahmotellaan ratkaisuja järjestelmää vaivaaviin ongelmiin. Työn tuloksena saatiin määriteltyä tuoterakenne, sekä tuotua vanhasta PDM:stä valintasäännöt ulos. Tälle datalle tehtiin muunnos Python-kielellä, jonka jälkeen se saatiin vietyä uuteen järjestelmään. Suunnittelumalleilla suunniteltiin mahdollinen integrointiratkaisu, ja uuden PDM-sovelluksen XML-datalle saatiin tehtyä muunnos Python-kielellä. Se vastaa muunnoksen jälkeen vanhan PDM-sovelluksen XMLmuotoa. Näin alihankkijan ei tarvitse tehdä muutoksia järjestelmäänsä uuden PDM:n tullessa käyttöön

Inhomogeneous Structures in Holographic Superfluids: II. Vortices

We study vortex solutions in a holographic model of Herzog, Hartnoll, and Horowitz, with a vanishing external magnetic field on the boundary, as is appropriate for vortices in a superfluid. We study relevant length scales related to the vortices and how the charge density inside the core of the vortex behaves as a function of temperature or chemical potential. We extract the critical superfluid velocity from the vortex solutions, study how it behaves as a function of the temperature, and compare it to earlier studies and to the Landau criterion. We also comment on the possibility of a Berezinskii-Kosterlitz-Thouless vortex confinement-deconfinement transition.Comment: 32 pages, 10 figures, typos corrected, references adde

Correlation functions in theories with Lifshitz scaling

The 2+1 dimensional quantum Lifshitz model can be generalised to a class of higher dimensional free field theories that exhibit Lifshitz scaling. When the dynamical critical exponent equals the number of spatial dimensions, equal time correlation functions of scaling operators in the generalised quantum Lifshitz model are given by a d-dimensional higher-derivative conformal field theory. Autocorrelation functions in the generalised quantum Lifshitz model in any number of dimensions can on the other hand be expressed in terms of autocorrelation functions of a two-dimensional conformal field theory. This also holds for autocorrelation functions in a strongly coupled Lifshitz field theory with a holographic dual of Einstein-Maxwell-dilaton type. The map to a two-dimensional conformal field theory extends to autocorrelation functions in thermal states and out-of-equilbrium states preserving symmetry under spatial translations and rotations in both types of Lifshitz models. Furthermore, the spectrum of quasinormal modes of scalar field perturbations in Lifshitz black hole backgrounds can be obtained analytically at low spatial momenta and exhibits a linear dispersion relation at z = d. At high momentum, the mode spectrum can be obtained in a WKB approximation and displays very different behaviour compared to holographic duals of conformal field theories. This has implications for thermalisation in strongly coupled Lifshitz field theories with z > 1.Peer reviewe

Inhomogeneous Structures in Holographic Superfluids I : Dark Solitons

25 pages, 17 figure files, LaTeXWe begin an investigation of inhomogeneous structures in holographic superfluids. As a first example, we study domain wall like defects in the 3+1 dimensional Einstein-Maxwell-Higgs theory, which was developed as a dual model for a holographic superconductor. In [1], we reported on such "dark solitons" in holographic superfluids. In this work, we present an extensive numerical study of their properties, working in the probe limit. We construct dark solitons for two possible condensing operators, and find that both of them share common features with their standard superfluid counterparts. However, both are characterized by two distinct coherence length scales (one for order parameter, one for charge condensate). We study the relative charge depletion factor and find that solitons in the two different condensates have very distinct depletion characteristics. We also study quasiparticle excitations above the holographic superfluid, and find that the scale of the excitations is comparable to the soliton coherence length scales.Peer reviewe

Thermalization and entanglement following a non-relativistic holographic quench

We develop a holographic model for thermalization following a quench near a quantum critical point with non-trivial dynamical critical exponent. The anti-de Sitter Vaidya null collapse geometry is generalized to asymptotically Lifshitz spacetime. Non-local observables such as two-point functions and entanglement entropy in this background then provide information about the length and time scales relevant to thermalization. The propagation of thermalization exhibits similar "horizon" behavior as has been seen previously in the conformal case and we give a heuristic argument for why it also appears here. Finally, analytic upper bounds are obtained for the thermalization rates of the non-local observables.Comment: 33 pages, 11 figures. v2: minor typos corrected, references added, a new section added in the appendix, published versio

Single Photon Lidar in Mobile Laser Scanning: The Sampling Rate Problem and Initial Solution via Spatial Correlations

Single photon lidars (in solid state form) offer several benefits over pulsed lidars, such as independence of micro-mechanical moving parts or rotating joints, lower power consumption, faster acquisition rate, and reduced size. When mass produced, they will be cheaper and smaller and thus very attractive for mobile laser scanning applications. However, as these lidars operate by receiving single photons, they are very susceptible to background illumination such as sunlight. In other words, the observations contain a significant amount of noise, or to be specific, outliers. This causes trouble for measurements done in motion, as the sampling rate (i.e. the measurement frequency) should be low and high at the same time. It should be low enough so that target detection is robust, meaning that the targets can be distinguished from the single-photon avalanche diode (SPAD) triggings caused by the background photons. On the other hand, the sampling rate should be high enough to allow for measurements to be done from motion. Quick sampling reduces the probability that a sample gathered during motion would contain data from more than a single target at a specific range. Here, we study the exploitation of spatial correlations that exist between the observations as a mean to overcome this sampling rate paradox. We propose computational methods for short and long range. Our results indicate that the spatial correlations do indeed allow for faster and more robust sampling of measurements, which makes single photon lidars more attractive in (daylight) mobile laser scanning

Gravitational collapse of thin shells: time evolution of the holographic entanglement entropy

Keränen V, Nishimura H, Stricker S, Taanila O, Vuorinen A. Gravitational collapse of thin shells: time evolution of the holographic entanglement entropy. Journal of High Energy Physics. 2015;2015(6): 126.We study the dynamics of gravitationally collapsing massive shells in AdS spacetime, and show in detail how one can determine extremal surfaces traversing them. The results are used to solve the time evolution of the holographic entanglement entropy in a strongly coupled dual conformal gauge theory, which is is seen to exhibit a regime of linear growth independent of the shape of the boundary entangling region and the equation of state of the shell. Our exact results are finally compared to those of two commonly used approximation schemes, the Vaidya metric and the quasistatic limit, whose respective regions of validity we quantitatively determine