In this paper we introduce a new option pricing mechanism for reducing the exposure problem encountered by bidding agents with complementary valuations when participating in sequential, second-price auction markets. Existing option pricing models have two main drawbacks: they either apply fixed exercise prices, which may deter bidders with low valuations, thereby decreasing allocative efficienc...

In large-scale grid environment, the authorization plays a vital role in access control to resources. For the demand of higher dynamicity, complexity and granularity on grid environment, a novel model named dynamic role-based access control (DRBAC) based on RBAC model is presented. DRBAC introduces conceptions of several objects such as rolegraph initial structure, atom role and middle role, an...

The local solution problem of multivariate Fredholm integral equations is studied. Recent research proved that for several function classes the complexity of this problem is closely related to the Gelfand numbers of some characterizing operators. The generalization of this approach to the situation of arbitrary Banach spaces is the subject of the present paper. Furthermore, an iterative algorit...

California jurisdictions have an extensive history of conducting post-election manual tallies of ballot records; they have performed this type audit since the 1960s when the use of lever and punchcard voting technologies became common statewide. We report findings from studying manual tally procedures in a handful of California counties. Through a combination of iterative procedure development ...

An individual-based model of the infectious disease spread among the urban population is considered. A system of stochastic equations, which describes changes in quantities of four population groups, susceptible, exposed, infected individuals and individuals in the state of remission, is built. The system of equations of the model is supplemented with correlations, which consider disease heavin...

In this paper we introduce a novel trading strategy for trading in continuous-double auctions for risky assets. The principle underlying our strategy is an optimising of the level of leverage using numerical methods. Previous studies have shown that similar strategies can perform well when tested against theoretical models of asset price processes such as geometric Brownian motion, or back-test...

We consider the problem of providing semantics for declarative languages, in a way that would be useful for enabling automated knowledge exchange. If we only have one (first order) language, we can formalize what we mean for a set of sentences to be a translation of another, by requiring that the two sets share the same models. However, in order to formalize translation for the case where the t...

A key strength of agent-based modelling is the ability to explore the upward-causation of micro-dynamics on the macro-level behaviour of a system. However, in policy contexts, it is also important to be able to represent downward-causation from the macro and mesolevels to the micro, and to represent decision-making at the macro level (i.e., by governments) in a sensible way. Though we cannot mo...

We are developing a virtual learning environment, which includes a math game with a teachable agent, the embodiment of the agent, and a social conversation with the agent. In this work we are using various methods for design and system development, with a focus on iterative methods, and high involvement of the user in the process. In this paper we discuss the motivation for and the applications...