A unifying Petri net model of non-interference and non-deducibility information flow security

In this paper we introduce FIFO Information Flow Nets (FIFN) as a model for describing information flow security properties. The FIFN is based on Petri nets and has been derived from the work described in [Var89], [Var90] and [Rou86]. Using this new model, we present the information flow security properties Non-Interference between Places (which corresponds to Non-Interference) and Non-Deducibility on Views (which corresponds to Non-Deducibility on Inputs). Then we consider a very general composition operation and show that neither Non-Interference on Places nor Non-Deducibility on Views is preserved under this composition operation. This leads us to a new definition of information flow security referred to as the Feedback Non-Deducibility on Views. We then show that this definition is preserved under the composition operation. This leads us to a new definition of information flow security referred to as the Feedback Non-Deducibility on Views. We then show that this definition is preserved under the composition operation. We then show some similarities between this property and the notion of Non-Deducibility on Strategies

Sign switch of Gaussian bending modulus for microemulsions; a self-consistent field analysis exploring scale invariant curvature energies

Bending rigidities of tensionless balanced liquid-liquid interfaces as occurring in microemulsions are predicted using self-consistent field theory for molecularly inhomogeneous systems. Considering geometries with scale invariant curvature energies gives unambiguous bending rigidities for systems with fixed chemical potentials: The minimal surface Im3m cubic phase is used to find the Gaussian bending rigidity, $\bar{\kappa}$, and a torus with Willmore energy $W=2 \pi^2$ allows for direct evaluation of the mean bending modulus, $\kappa$. Consistent with this, the spherical droplet gives access to $2 \kappa + \bar{\kappa}$. We observe that $\bar{\kappa}$ tends to be negative for strong segregation and positive for weak segregation; a finding which is instrumental for understanding phase transitions from a lamellar to a sponge-like microemulsion. Invariably, $\kappa$ remains positive and increases with increasing strength of segregation.Comment: 7 pages, 5 figure

Telecommunications infrastructure and economic growth: Evidence from developing countries.

Often, it has been observed that telecommunication infrastructure development and economic growth proceed together. While this relationship has been studied in the context of developed (OECD) countries, in this study, we investigate this simultaneous relationship between telecommunications and the economic growth, using data for developing countries. Using 3SLS, we estimate a system of equations that endogenize economic growth and telecom penetration (respectively production function and demand for telecom services), along with supply of telecom investment and growth in telecom penetration. We estimate this system of equations separately for main telephone lines and cell phones. We find that while traditional economic factors explain demand for main line phones, they do not explain demand for cell phones. We also find significant impacts of cellular services on national output, when we control for the effects of capital and labour. The impact of telecom penetration on total output is, however, significantly lower for developing countries than that reported for OECD countries, dispelling the convergence hypothesis.Telecommunication ; Infrastructure ; Economic growth ; Reverse causality ; Developing countries

Collision-aware Task Assignment for Multi-Robot Systems

We propose a novel formulation of the collision-aware task assignment (CATA) problem and a decentralized auction-based algorithm to solve the problem with optimality bound. Using a collision cone, we predict potential collisions and introduce a binary decision variable into the local reward function for task bidding. We further improve CATA by implementing a receding collision horizon to address the stopping robot scenario, i.e. when robots are confined to their task location and become static obstacles to other moving robots. The auction-based algorithm encourages the robots to bid for tasks with collision mitigation considerations. We validate the improved task assignment solution with both simulation and experimental results, which show significant reduction of overlapping paths as well as deadlocks

Bringing Global Sourcing into the Classroom: Experiential Learning via Software Development Project

Global sourcing of software development has imposed new skill requirements on Information Technology (IT) personnel. In the U.S., this has resulted in a paradigm shift from technical to softer skills such as communications and virtual team management. Higher education institutions must, consequently, initiate innovative curriculum transformations to better prepare students for these emerging workforce needs. This paper describes one such venture between Marquette University (MU), U.S.A. and Management Development Institute (MDI), India, wherein IT students at MU collaborated with Management Information Systems (MIS) students at MDI on an offshore software development project. The class environment replicated an offshore client/vendor relationship in a fully virtual setting while integrating communications and virtual team management with traditional IT project management principles. Course measures indicated that students benefited from this project, gained first-hand experience in the process of software offshoring, and learned skills critical for conduct of global business. For faculty considering such initiatives, we describe the design and administration of this class over two semesters, lessons learned from our engagement, and factors critical to success of such initiatives and those detrimental to their sustenance

Bringing Global Sourcing into The Classroom: Experiential Learning Via a Global Software Development Project

The growing trend in offshore software development has imposed new skills requirements on collaborating global partners. In the U.S. this has translated into skill sets that include communications, project management, business analysis, and team management. In a virtual setting, these skills take on a complex proportion. This paper describes an educational initiative in offshore software development between undergraduate students enrolled in a project management course at Marquette University, USA and graduate business students enrolled in an Information Systems Analysis and Design course at Management Development Institute, India. The course replicated an offshore client/vendor relationship in a virtual setting. For faculty considering such initiatives, this paper describes the setting and factors critical to success of this initiative and cautions against others that can be detrimental to such an effort