Analyzing potential age cohort effects in car ownership and residential location in the metropolitan region of Amsterdam

Previous research on car ownership has described ownership using a combination of socio-economic factors, demographics, individual preferences and residential factors. However, over the years people's attitudes towards car ownership have changed as new generations are being formed. A new generation of young adults has a different view on car ownership compared to the older generation when car ownership was still a display of status. In this research a first attempt is made to disentangle the effects of age on car ownership and residential location. A discrete choice modelling approach is used where we jointly model car ownership and residential location in the metropolitan region of Amsterdam. We will start from the multinomial logit model and from there try more complex models which capture correlation among alternatives, and introduce a cohort effect for people of a certain age using a nested panel model. The main result of the model shows that car ownership in the city shows more variation in age than car ownership outside of the city

Probing the spatial dispersion in a dense atomic vapor near a dielectric interface

Quantum optics and Quantum information - OU

Topological regluing of rational functions

Regluing is a topological operation that helps to construct topological models for rational functions on the boundaries of certain hyperbolic components. It also has a holomorphic interpretation, with the flavor of infinite dimensional Thurston--Teichm\"uller theory. We will discuss a topological theory of regluing, and trace a direction in which a holomorphic theory can develop.Comment: 38 page

Measurement of the excitation dependence of the Lorentz local-field shift

Quantum Matter and Optic

Understanding the relation between travel duration and station choice behavior of cyclists in the metropolitan region of Amsterdam

With 35,000 km of bicycle pathways, cycling is common among persons of all ages less than 65 years in the Netherlands. Bicycle is often seen as a standalone travel mode but when integrated as part of a multimodal trip with train, it can be an important solution for long distance journeys, offering increased flexibility and faster access time compared to other travel modes. In this paper we investigate which factors influence departure station choice on combined bicycle–train and bicycle-metro trips in the metropolitan region of Amsterdam. Data from a mobile app was used to track an individual’s travel behavior over the years 2018 and 2019. A discrete choice model was estimated to see whether people prefer to park their bicycle at the station with the shortest travel duration or one of the stations with a longer travel duration. The final results show that level of education and age negatively influence the choice for cycling to the second closest station. Furthermore, the results show that people with an origin inside Amsterdam prefer to travel to a train station regardless of their destination

Bicycle parking in station areas in the Netherlands

Cities in the Netherlands have encouraged cycling in order to create a more healthy, liveable and sustainable environment. Accordingly, cycling has become an important travel mode in cities for both unimodal and multimodal travel. Consequently, the increase of bicycle use results in an increase in the demand for bicycle parking, thus encouraging illegal bicycle in station areas where supply is unable to meet demand. As space becomes scarce in these areas, managing the existing parking supply becomes crucial in the urban environment. This research attempts to explain bicycle parking behavior by finding determinants for parking near a station with a metro service, train service or both services at the same location. The results not only show that the determinants for parking in these station areas differ, but also that each station areas attracts different groups of people

Proof of the Hyperplane Zeros Conjecture of Lagarias and Wang

We prove that a real analytic subset of a torus group that is contained in its image under an expanding endomorphism is a finite union of translates of closed subgroups. This confirms the hyperplane zeros conjecture of Lagarias and Wang for real analytic varieties. Our proof uses real analytic geometry, topological dynamics and Fourier analysis.Comment: 25 page

Time-dependent Stochastic Modeling of Solar Active Region Energy

A time-dependent model for the energy of a flaring solar active region is presented based on a stochastic jump-transition model (Wheatland and Glukhov 1998; Wheatland 2008; Wheatland 2009). The magnetic free energy of the model active region varies in time due to a prescribed (deterministic) rate of energy input and prescribed (random) flare jumps downwards in energy. The model has been shown to reproduce observed flare statistics, for specific time-independent choices for the energy input and flare transition rates. However, many solar active regions exhibit time variation in flare productivity, as exemplified by NOAA active region AR 11029 (Wheatland 2010). In this case a time-dependent model is needed. Time variation is incorporated for two cases: 1. a step change in the rates of flare jumps; and 2. a step change in the rate of energy supply to the system. Analytic arguments are presented describing the qualitative behavior of the system in the two cases. In each case the system adjusts by shifting to a new stationary state over a relaxation time which is estimated analytically. The new model retains flare-like event statistics. In each case the frequency-energy distribution is a power law for flare energies less than a time-dependent rollover set by the largest energy the system is likely to attain at a given time. For Case 1, the model exhibits a double exponential waiting-time distribution, corresponding to flaring at a constant mean rate during two intervals (before and after the step change), if the average energy of the system is large. For Case 2 the waiting-time distribution is a simple exponential, again provided the average energy of the system is large. Monte Carlo simulations of Case~1 are presented which confirm the analytic estimates. The simulation results provide a qualitative model for observed flare statistics in active region AR 11029.Comment: 25 pages, 9 figure

Bounding Helly numbers via Betti numbers

We show that very weak topological assumptions are enough to ensure the existence of a Helly-type theorem. More precisely, we show that for any non-negative integers $b$ and $d$ there exists an integer $h(b,d)$ such that the following holds. If $\mathcal F$ is a finite family of subsets of $\mathbb R^d$ such that $\tilde\beta_i\left(\bigcap\mathcal G\right) \le b$ for any $\mathcal G \subsetneq \mathcal F$ and every $0 \le i \le \lceil d/2 \rceil-1$ then $\mathcal F$ has Helly number at most $h(b,d)$. Here $\tilde\beta_i$ denotes the reduced $\mathbb Z_2$-Betti numbers (with singular homology). These topological conditions are sharp: not controlling any of these $\lceil d/2 \rceil$ first Betti numbers allow for families with unbounded Helly number. Our proofs combine homological non-embeddability results with a Ramsey-based approach to build, given an arbitrary simplicial complex $K$, some well-behaved chain map $C_*(K) \to C_*(\mathbb R^d)$.Comment: 29 pages, 8 figure