Heribert Vollmer : Boolean functions and Post’s lattice with applications to complexity theory. A Boolean functions f can be obtained from a set B of Boolean functions by superposition, if f can be written as a nested composition of functions from B. In the 1940’s, Emil Post determined the complete list of all sets of Boolean functions closed under superposition, and for each of them, he constr...

For a fixed digraphH, the problem of deciding whether there exists a homomorphism from an input digraph G to H is known as the H-colouring problem. An algebraic approach to this problem was pioneered by Jeavons et. al. in the context of the more general constraint satisfaction problem. Results by Larose and Zádori and by Maróti and McKenzie allows one to interpret the algebraic approach in term...

We investigate the computational complexity of the problem of counting the locally maximal satisfying assignments of a Constraint Satisfaction Problem (CSP) over the Boolean domain {0, 1}. A satisfying assignment is locally maximal if any new assignment which is obtained from it by changing a 0 to a 1 is unsatisfying. For each constraint language Γ, #LocalMaxCSP(Γ) denotes the problem of counti...

Knowledge of the security zone classification of devices in an enterprise information technology (IT) infrastructure is essential in many enterprise IT transformation and optimization activities. We describe a systematic and semi-automated approach for discovering the security zone classification of devices in an enterprise network. For reduced interference with normal operation of the IT infra...

The Constraint Satisfaction Problem (CSP) framework offers a simple and sound basis for representing and solving simple decision problems, without uncertainty. This paper is devoted to an extension of the CSP frame­ work enabling us to deal with some decisions problems under uncertainty. This extension relies on a differen­ tiation between the agent-controllable decision vari­ ables and the unc...

A constraint satisfaction problem has compactness if any infinite set of constraints is satisfiable whenever all its finite subsets are satisfiable. We prove a sufficient condition for compactness, which holds for a range of problems including those based on the well-known Interval Algebra (IA) and RCC8. Furthermore, we show that compactness leads to a useful necessary and sufficient condition ...

In the domain of qualitative constraint reasoning, a subfield of AI which has evolved in the last 25 years, a large number of calculi for efficient reasoning about space and time has been developed. Reasoning problems in such calculi are usually formulated as constraint satisfaction problems. For temporal and spatial reasoning, these problems often have infinite domains, which need to be abstra...

the current study aims to measure the efficiency of primary health care units completed in health sector of rural azad jammu and kashmir (ajk) and to compare it across developed and deprived regions.operational efficiency and beneficiary efficiency of a total of 32 basic health units (bhus) were measured through data envelopment analysis (dea) by using different input and output variables. inde...

this article analyses the push and pull factors that bring visitors to the iranian national parks. the study used a structured questionnaire to collect data on these factors and the socio-demographic profile of the visitors. survey conducted in boujagh national park, an area of 3177 hectares located in the north of the iran, produced 400 questionnaires. the factor analysis identified four push ...

background: marital satisfaction is affected by many factors. satisfaction with one's sexual life tends to be a pivotal factor in marital satisfaction. in iran, socio-cultural and political limitations are obstacles for sexuality-related studies, therefore, in­sufficient information is available in the area. unique in its own, in this paper we report how sexual relationships relate to mari­tal ...