Multi-type TASEP in discrete time

The TASEP (totally asymmetric simple exclusion process) is a basic model for an one-dimensional interacting particle system with non-reversible dynamics. Despite the simplicity of the model it shows a very rich and interesting behaviour. In this paper we study some aspects of the TASEP in discrete time and compare the results to the recently obtained results for the TASEP in continuous time. In particular we focus on stationary distributions for multi-type models, speeds of second-class particles, collision probabilities and the "speed process". In discrete time, jump attempts may occur at different sites simultaneously, and the order in which these attempts are processed is important; we consider various natural update rules.Comment: 36 page

How are you doing, Europe? Mapping social imbalances in the EU

At the end of May, Europeans will elect a new Euro- pean Parliament and soon after a new European Commis- sion will begin its five-year mandate. The political chang- ing of the guard in the European Union (EU) comes at a time of economic recovery: per capita income has been growing by about two percent annually for the last three years, and growth has recently returned to every EU mem- ber state. Unemployment has been falling across the EU in the last year and now stands at an average of 6.7 per- cent – marking a new all-time low. It seems that Europe is doing well: the economic tide is rising and, for the first time since the outbreak of the global financial crisis in 2008, all boats are lifting

Long-range last-passage percolation on the line

We consider directed last-passage percolation on the random graph G = (V,E) where V = Z and each edge (i,j), for i < j, is present in E independently with some probability 0 < p <= 1. To every present edge (i,j) we attach i.i.d. random weights v_{i,j} > 0. We are interested in the behaviour of w_{0,n}, which is the maximum weight of all directed paths from 0 to n, as n tends to infinity. We see two very different types of behaviour, depending on whether E[v_{i,j}^2] is finite or infinite. In the case where E[v_{i,j}^2] is finite we show that the process has a certain regenerative structure, and prove a strong law of large numbers and, under an extra assumption, a functional central limit theorem. In the situation where E[v_{i,j}^2] is infinite we obtain scaling laws and asymptotic distributions expressed in terms of a "continuous last-passage percolation" model on [0,1]; these are related to corresponding results for two-dimensional last-passage percolation with heavy-tailed weights obtained by Hambly and Martin.Comment: 38 pages. Accepted by Annals of Applied Probabilit

Identification and Estimation of Dynamic Games

This paper studies the identification problem in infinite horizon Markovian games and proposes a generally applicable estimation method. Every period firms simultaneously select an action from a finite set. We characterize the set of Markov equilibria. Period profits are a linear function of equilibrium choice probabilities. The question of identification of these values is then reduced to the existence of a solution to this linear equation system. We characterize the identification conditions. We propose a simple estimation procedure which follows the steps in the identification argument. The estimator is consistent, asymptotic normally distributed, and efficient. We have collected quarterly time series data on pubs, restaurants, coffeehouses, bakeries and carpenters for two Austrian towns between 1982 and 2002. A dynamic entry game is estimated in which firms simultaneously decide whether to enter, remain active, or exit the industry. The period profit estimates are used to simulate the equilibrium behavior under a policy experiment in which a unit tax is imposed on firms deciding to enter the industry.

Evaluating EU Regional Policy: Many Empirical Specifications, One (Unpleasant) Result

Numerous studies have focused on the role of EU regional policy in fostering growth and convergence among European regions, why conducting another one? We argue that two facts are still lacking in the actual academic debate in order to get a sound empirical identification strategy and reliable results: First, one should take the theoretical underpinnings of regional growth models more serious, and second, a likewise careful account of the role of spatial dependence in the underlying data is needed. Though research has increasingly become aware of the latter point as important control factor for regional heterogeneity and omitted variables, in empirical operationalization still the ad-hoc inclusion of a hardly interpretable ‘catch-all’ spatial lag term of the endogenous variable is the first choice. We rather follow the lines of new theoretical and empirical approaches aiming at directly quantifying interregional spillovers associated with the amount of funds granted to lagging regions and their neighborhood. The dataset includes 127 NUTS1/-2 regions within the EU15 over the decade 1997-2007. In the spotlight of the investigation are the Objective 1 payments which are provided for lagging regions with a GDP p.c. of less than 75% of the EU average. These payments shall represent the main instrument to fulfill the central aim of European regional policy, the boost of convergence and harmonic growth over the EU. They represent about two third of the whole European cohesion policy. In our estimations we run a neoclassical convergence model in mainly four different specifications. On the one hand we separate in the aspatial and spatial models. On the other hand we run additive and multiplicative applications in order to consider the right coefficient interpretations. We estimate the model in various econometric specifications to point out the effectiveness of these funding. Our results all hint to the unpleasant result that EU structural funds objective 1 funding has a remarkably little or even negative direct impact on regional growth within the EU15. The spatial funding effects turn into negative significance in the most model specifications.

Fermionic reaction coordinates and their application to an autonomous Maxwell demon in the strong coupling regime

We establish a theoretical method which goes beyond the weak coupling and Markovian approximations while remaining intuitive, using a quantum master equation in a larger Hilbert space. The method is applicable to all impurity Hamiltonians tunnel-coupled to one (or multiple) baths of free fermions. The accuracy of the method is in principle not limited by the system-bath coupling strength, but rather by the shape of the spectral density and it is especially suited to study situations far away from the wide-band limit. In analogy to the bosonic case, we call it the fermionic reaction coordinate mapping. As an application we consider a thermoelectric device made of two Coulomb-coupled quantum dots. We pay particular attention to the regime where this device operates as an autonomous Maxwell demon shoveling electrons against the voltage bias thanks to information. Contrary to previous studies we do not rely on a Markovian weak coupling description. Our numerical findings reveal that in the regime of strong coupling and non-Markovianity, the Maxwell demon is often doomed to disappear except in a narrow parameter regime of small power output.Comment: 18 pages incl. references, appendix and 10 figures; accepted versio

Software-Defined Networks Supporting Time-Sensitive In-Vehicular Communication

Future in-vehicular networks will be based on Ethernet. The IEEE Time-Sensitive Networking (TSN) is a promising candidate to satisfy real-time requirements in future car communication. Software-Defined Networking (SDN) extends the Ethernet control plane with a programming option that can add much value to the resilience, security, and adaptivity of the automotive environment. In this work, we derive a first concept for combining Software-Defined Networking with Time-Sensitive Networking along with an initial evaluation. Our measurements are performed via a simulation that investigates whether an SDN architecture is suitable for time-critical applications in the car. Our findings indicate that the control overhead of SDN can be added without a delay penalty for the TSN traffic when protocols are mapped properly.Comment: To be published at IEEE VTC2019-Sprin

Simulation of Mixed Critical In-vehicular Networks

Future automotive applications ranging from advanced driver assistance to autonomous driving will largely increase demands on in-vehicular networks. Data flows of high bandwidth or low latency requirements, but in particular many additional communication relations will introduce a new level of complexity to the in-car communication system. It is expected that future communication backbones which interconnect sensors and actuators with ECU in cars will be built on Ethernet technologies. However, signalling from different application domains demands for network services of tailored attributes, including real-time transmission protocols as defined in the TSN Ethernet extensions. These QoS constraints will increase network complexity even further. Event-based simulation is a key technology to master the challenges of an in-car network design. This chapter introduces the domain-specific aspects and simulation models for in-vehicular networks and presents an overview of the car-centric network design process. Starting from a domain specific description language, we cover the corresponding simulation models with their workflows and apply our approach to a related case study for an in-car network of a premium car

Hacia la adaptación al cambio climático

Climate change adaptation has been growing in importance since the beginning of the 21st century. Historically adaptation, not to climate change but to extreme events, was deeply rooted in many societies and their land-use structures. With industrialization, and especially the increase in globalization since the 1990’s the importance of appropriate adaptation has slowly decreased, leading to increased exposure and risks of human settlements in areas potentially affected by climate change impacts (e.g. sea level rise) and / or extreme events (natural hazards). In order to implement climate change adaptation sustainably feasible solutions should be identified, i.e. viable and acceptable from socio-economic point of views. The identification of such feasible solutions goes beyond pure scientific analysis but incorporates stakeholders, decision-makers and local knowledge.La adaptación al cambio climático ha ido cobrando importancia desde comienzos del siglo actual. Históricamente la adaptación, no al cambio climático sino a los eventos atmosféricos extremos, estaba profundamente arraigada en muchas sociedades y en su forma de ocupar el territorio. Con la industrialización y especialmente con el aumento de la globalización desde los años noventa del pasado siglo, la importancia de una adecuada adaptación al territorio ha ido perdiendo protagonismo, lo que ha aumentado la exposición y el riesgo de los asentamientos humanos en áreas potencialmente afectadas por los impactos del cambio climático (p.e. subida del nivel de mar) y/o por eventos extremos (peligros naturales). Para desarrollar medidas de adaptación al cambio climático es necesario identificar soluciones viables, es decir, viables y aceptables desde el punto de vista socioeconómico. La identificación de estas soluciones factibles va más allá del análisis científico puro puesto que incorpora a todas las partes interesadas, incluidos los responsables en la toma de decisiones y el propio conocimiento local

Integration of natural hazards, risk and climate change into spatial planning practices

Most countries of Europe, as well as many countries in other parts of the world, are experiencing an increased impact of natural hazards. It is often speculated, but not yet proven, that climate change might influence the frequency and magnitude of certain hydro-meteorological natural hazards. What has certainly been observed is a sharp increase in financial losses caused by natural hazards worldwide. Eventhough Europe appears to be a space that is not affected by natural hazards to such catastrophic extents as other parts of the world are, the damages experienced here are certainly increasing too. Natural hazards, climate change and, in particular, risks have therefore recently been put high on the political agenda of the EU. In the search for appropriate instruments for mitigating impacts of natural hazards and climate change, as well as risks, the integration of these factors into spatial planning practices is constantly receiving higher attention. The focus of most approaches lies on single hazards and climate change mitigation strategies. The current paradigm shift of climate change mitigation to adaptation is used as a basis to draw conclusions and recommendations on what concepts could be further incorporated into spatial planning practices. Especially multi-hazard approaches are discussed as an important approach that should be developed further. One focal point is the definition and applicability of the terms natural hazard, vulnerability and risk in spatial planning practices. Especially vulnerability and risk concepts are so many-fold and complicated that their application in spatial planning has to be analysed most carefully. The PhD thesis is based on six published articles that describe the results of European research projects, which have elaborated strategies and tools for integrated communication and assessment practices on natural hazards and climate change impacts. The papers describe approaches on local, regional and European level, both from theoretical and practical perspectives. Based on these, passed, current and future potential spatial planning applications are reviewed and discussed. In conclusion it is recommended to shift from single hazard assessments to multi-hazard approaches, integrating potential climate change impacts. Vulnerability concepts should play a stronger role than present, and adaptation to natural hazards and climate change should be more emphasized in relation to mitigation. It is outlined that the integration of risk concepts in planning is rather complicated and would need very careful assessment to ensure applicability. Future spatial planning practices should also consider to be more interdisciplinary, i.e. to integrate as many stakeholders and experts as possible to ensure the sustainability of investments.Tässä väitöskirjassa analysoidaan ja tarkastellaan, kuinka yhteiskuntaa voitaisiin suojella aluesuunnittelun keinoin nykyistä paremmin luonnonhasardien ja ilmastonmuutoksen vaikutuksia vastaan. Useat Euroopan ja muun maailman valtiot kärsivät kasvavista luonnonhasardien vaikutuksista ja niiden aiheuttamista taloudellisista tappioista. Usein esitetään, joskaan sitä ei ole vielä tieteellisesti todistettu, että ilmastonmuutos saattaa vaikuttaa eräiden luonnonhasardien esiintymiseen ja voimakkuuteen. Vaikka Eurooppa näyttäisi olevan turvassa muuta maailmaa koettelevilta luonnonkatastrofeilta, myös Euroopassa kärsityt vahingot ovat selvästi lisääntyneet. Tämän vuoksi luonnonhasardit ja ilmastonmuutos ovat hiljattain nostettu keskeiseksi poliittiseksi prioriteetiksi myös Euroopan unionissa. Aluesuunnittelun avulla kyetään hallitsemaan paremmin luonnonhasardien ja mahdollisen ilmastonmuutoksen vaikutuksia. Aluesuunnittelun mahdollisuudet olemassa olevan infrastruktuurin ja rakennuskannan suojelemiseksi ovat rajalliset, mutta sen avulla voidaan ohjata tulevaa maankäyttöä ja siten suojella paremmin tulevaisuuden rakennelmia. Nykyisen käytännön mukaisesti aluesuunnittelussa arvioidaan usein kerrallaan vain yhtä hasardia, kuten tulvia. Väitöskirjan tekijän mukaan yksittäisten hasardien sijaan olisi tärkeää tarkastella laaja-alaisesti useampia vaaratekijöitä samanaikaisesti. Kun kyse on tulvista, pitäisi tutkia myrskyjen, myrskyvuoksien ja tulvien keskinäistä vaikutussuhdetta. Tämän lisäksi olisi arvioitava ilmastonmuutoksen vaikutuksia näihin uhkiin eli tässä tapauksessa myrskyjen lukumäärän mahdollista kasvua ja merenpinnan nousua. Myös altistuminen olisi syytä ottaa paremmin huomioon esimerkiksi sen arvioimiseksi, millaisia vahinkoja luonnonhasardit voivat viime kädessä saada aikaan. Lisäksi olisi selvitettävä tällaisten vahinkojen alueelliset vaikutukset. Työn teoriaosassa käsitellään termien luonnonhasardi, altistuminen ja riski määritelmiä sekä niiden sovellettavuutta aluesuunnitteluun. Tekijä esittää, että arvioinnit ja niitä seuraava kartoitus olisi pidettävä riittävän yksinkertaisina, jotta laaja yleisö voi ymmärtää niitä. Väitöskirja perustuu kuuteen julkaistuun artikkeliin, joissa käsitellään tuloksia eurooppalaisista tutkimushankkeista. Näissä tutkimusprojekteissa on kehitetty menetelmiä luonnonhasardien ja ilmastonmuutoksen identifioimiseen sekä arvioitu niiden laajuutta. Artikkeleissa kuvataan paikallisia, alueellisia (Itämeren alue) ja Euroopan laajuisia hankkeita sekä teoreettisesta että käytännöllisestä näkökulmasta. Tekijä esittää päätelmänään, että luonnonhasardeilla ja ilmastonmuutoksella olisi oltava nykyistä merkittävämpi rooli aluesuunnittelussa. Hasardien keskinäisiin vaikutussuhteisiin olisi syytä kiinnittää enemmän huomiota ja niiden aiheuttamien vahinkojen mahdollista laajuutta olisi arvioitava tarkemmin. Lisäksi olisi suositeltavaa ottaa huomioon asiantuntijoiden ja uhkista mahdollisesti kärsivien ihmisten mielipiteet, jotta vahingot voitaisiin minimoida ja tulevat investoinnit turvata