Nonlinear Compressive Particle Filtering

Many systems for which compressive sensing is used today are dynamical. The common approach is to neglect the dynamics and see the problem as a sequence of independent problems. This approach has two disadvantages. Firstly, the temporal dependency in the state could be used to improve the accuracy of the state estimates. Secondly, having an estimate for the state and its support could be used to reduce the computational load of the subsequent step. In the linear Gaussian setting, compressive sensing was recently combined with the Kalman filter to mitigate above disadvantages. In the nonlinear dynamical case, compressive sensing can not be used and, if the state dimension is high, the particle filter would perform poorly. In this paper we combine one of the most novel developments in compressive sensing, nonlinear compressive sensing, with the particle filter. We show that the marriage of the two is essential and that neither the particle filter or nonlinear compressive sensing alone gives a satisfying solution.Comment: Accepted to CDC 201

Corruption under moral hazard

In this theoretical analysis, the"principal"can be the head of the tax collection agency (or"government"or even citizens), the"supervisor"can be the tax collector, and the"agent"can be the taxpayer. The principal, interested in controlling an agent's socially costly activity ("cheating"), hires the supervisor to save on monitoring costs. The agent may bribe the tax collector to suppress reporting, but bribery can be eliminated by the agency head if he institutes enough investigations and sets rewards high enough and penalties steep enough. When penalties and rewards are constrained, some corruption will exist even under a rational approach to pursuing the agency's objectives. Anti-corruption efforts will have higher costs than benefits unless they successfully address these constraints. The agency's implementation costs, and thus the scope for corruption, are defined by constraints on penalties and rewards relative to costs of monitoring and investigation. For example, if the agency head is extremely handicapped in his ability to detect bribery (by a high burden of proof and cost of investigation, and a civil service pay scale that is too flat and rigid), he cannot really reward good employees or make dishonest employees suffer. The analysis assumes that the principal can commit in advance to a certain likelihood of being caught engaging in bribery. Creating an independent anti-corruption commission (like those in Hong Kong and New South Wales) may be interpreted as a way of making such a commitment. In Hong Kong two-thirds of reports to the commission are made in full name, an indication that it has attained a reputation for independence and efficiency. The"whistleblower act"in the United states (promising rewards and protection for informants), as well as separation of powers and independent courts, also function as commitment. Corruption exists not only in poorly designed but also in sophisticated systems. It can profitably be reduced only by improving general incentives. Advances in courts, investigations, freedom of the press, and flow of information can allow more performance-based rewards and penalties.Environmental Economics&Policies,Economic Theory&Research,Corruption&Anitcorruption Law,Public Sector Corruption&Anticorruption Measures,Banks&Banking Reform

Do motorways shape urban growth? Analysis of growth patterns with micro-level data – before and after road openings in two Danish motorway corridors

The paper is an offspring from the Research project Town, Road and Landscape that aims to assess the effect of the Danish motorway network (specifically the last 20 years) on urban growth and interaction patterns. As one of the main interests of the project is the changing urban form and the changing character of the roadscape, the impact of the motorway is in part analysed with micro level data, spatial statistics and GIS – to allowing mapping of changing development trends in motorway corridors. The paper presents analysis of the impact of motorway openings on urban form in two Danish motorway corridors. The analysis is based on a before and after perspective – where the building activity and its location (building register with address coordinates) after the opening of the motorway is compared to building activity in the years before the construction of the motorway. Preliminary results suggest that the motorway most markedly influences the location of non-residential building activities within the city – in favour of locations near the entrance points to/from the motorway network. The development can be explained in part by municipal planning, which in some instances has opened up the new locations for development far ahead of market demand – and in part by an increasing demand for exposed and accessible sites for business development which still seems to be in its beginning.

Predictive Control of Autonomous Kites in Tow Test Experiments

In this paper we present a model-based control approach for autonomous flight of kites for wind power generation. Predictive models are considered to compensate for delay in the kite dynamics. We apply Model Predictive Control (MPC), with the objective of guiding the kite to follow a figure-of-eight trajectory, in the outer loop of a two level control cascade. The tracking capabilities of the inner-loop controller depend on the operating conditions and are assessed via a frequency domain robustness analysis. We take the limitations of the inner tracking controller into account by encoding them as optimisation constraints in the outer MPC. The method is validated on a kite system in tow test experiments.Comment: The paper has been accepted for publication in the IEEE Control Systems Letters and is subject to IEEE Control Systems Society copyright. Upon publication, the copy of record will be available at http://ieeexplore.ieee.or