We present a dynamic programming approach for the solution of first-order Markov decisions processes. This technique uses an MDP whose dynamics is represented in a variant of the situation calculus allowing for stochastic actions. It produces a logical description of the optimal value function and policy by constructing a set of first-order formulae that minimally partition state space accordin...

The cartogram, or value-by-area map, is a popular technique for cartographically representing social data. Such maps visually equalize a basemap prior to mapping a social variable by adjusting the size of each enumeration unit by a second, related variable. However, to scale the basemap units according to an equalizing variable, cartograms must distort the shape and/or topology of the original ...

This is a collection of open problems presented at the Lorentz Workshop “Enumeration Algorithms using Structure” which took place at the Lorentz Center of the University of Leiden (The Netherlands), August 24 30, 2015. The workshop brought together researchers interested in various aspects of enumeration algorithms; in particular classical output-sensitive enumeration including output-polynomia...

This paper gives two definability results in the local theory of the ω-enumeration degrees. First we prove that the local structure of the enumeration degrees is first order definable as a substructure of the ω-enumeration degrees. Our second result is the definability of the the classes Hn and Ln of the highn and lown ω-enumeration degrees. This allows us to deduce that the first order theory ...

Enumeration of search spaces belonging to join queries, so far comprises large sets of isomorphic processing trees, i.e. trees that can be equalized by only commutative exchange of the input relations to the operators. Since these diierences can be handled eeectively by the costing method it is suucient to focus on the enumeration of non-isomorphic processing trees only 2]. This restriction red...

Considerable efforts have been spent in studying subgraph problem. Traditional subgraph containment query is to retrieve all database graphs which contain the query graph g. A variation to that is to find all occurrences of a particular pattern(the query) in a large database graph. We call it subgraph matching problem. The state of art solution to this problem is GADDI. In this paper, we will p...

A seminal technique of theoretical physics calledWick’s theorem interprets the Gaussian matrix integral of the products of the trace of powers of Hermitian matrices as the number of labelled maps with a given degree sequence, sorted by their Euler characteristics. This leads to the map enumeration results analogous to those obtained by combinatorial methods. In this paper we show that the enume...

Given a combinatorial search problem, it may be highly useful to enumerate its (all) solutions besides just finding one solution, or showing that none exists. The same can stated about optimal if an objective function is provided. This work goes beyond the bare enumeration of and addresses computational task solution by optimality (SEO). studied in context Answer Set Programming (ASP) where (op...

An efficient variation of the sphere decoding (SD) is the orthotope sphere decoding (OSD). In simulations for many channels, the OSD has lower complexity than the SD. For this lower complexity achieving algorithm, there have been no enumeration schemes. In this paper, we present the orthotopic Schnorr-Echner (OSE) enumeration to further reduce the complexity of the OSD. By using O-metric for th...

background: the consumption of healthy food is considered as an essential need to devoid the physical, chemical, and biological hazards. the importance of this issue is more conspicuous in places such as hospitals where people with somehow compromised immune systems are under treatment. therefore, this research aimed to evaluate the microbiological quality of food contact surfaces in a kitchen ...