Marios Charalambides

The distribution of zeros of a class of Jacobi polynomials

Polynomials whose coefficients are successive derivatives of a class of generalized Laguerre polynomials evaluated at x = 0 are shown to be stable. These polynomials can be expressed in terms of Jacobi polynomials. The authors also prove that a related family of polynomials, depending on a parameter, possess only real and negative zeros. A special class of stability-preserving operators is also investigated.

A Profit Optimisation Decision Support Tool for the Offshore Aquaculture Industry

Abstract It has long been accepted that fish and seafood contribute positively to human health and consumer well-being. However, supply of seafood from wild catches steadily decreases and aquaculture gradually fills the gap of an ever increasing seafood market. In fact, aquaculture has been recognized as one of the fastest growing industries worldwide raising concern regarding fishmeal stock sustainability. This paper presents a profit optimization decision support tool for the Eastern Mediterranean offshore aquaculture industry, enabling just-in-time production of fish stock with minimum slack of mature fish stock in breeding cages. In detail, (a) a simulation model of involved cost elements is introduced, enabling (b) model development. Finally, a case study application of the model is presented.

A stochastic model with interacting managerial operating options and debt rescheduling

We develop a stochastic continuous time trade-off model with optimal capital structure that incorporates managements selection of optimal investment timing and switching between full-scale operations, reorganization and rescheduling and termination of operations (liquidation). We show that the presence of a firms option for debt rescheduling reduces firm value by reducing the managements ability to raise debt. This negative impact on debt capacity is reduced in the presence of higher switching costs incurred by shareholders when seeking bankruptcy protection and debt rescheduling. Larger anticipated debt reduction in rescheduling results in the management (acting in the shareholders’ interests) delaying returning to active full-scale operations which results in larger debt risk and credit spreads. On the positive side, more significant anticipated debt reduction in rescheduling results in reduced agency costs between shareholders and debt holders.

A general stability theorem with applications

The author presents a generalization of recent stability theorems. Polynomials whose coefficients are successive derivatives of a class of orthogonal functions evaluated at x = c, where c is a constant, are shown to fit in this general framework. Special reference is made to the ones related to the classical orthogonal polynomials. Related families of polynomials with real negative roots are also introduced.

Quality evaluation of residential houses: the development of a real-time quality assessment tool

The construction industry has been heavily affected by the economic crisis. Product differentiation and cost reduction through improved qualities could be the way out. However, applying quality control to the construction industry is a challenging task since construction projects are highly customised, constituting the application of statistical process control principles extremely difficult. This paper presents the constituting elements of a real-time quality assessment tool for the residential housing sector. It has been designed to be used primarily for internal company purposes. In particular, utilising the tool for assessing, in real-time, the quality of the projects currently in-progress and comparing the quality of completed projects and consequently drawing conclusions about the company’s quality progress. The tool’s structure comprises of 1a model of the construction process 2a checklist 3a quality scoring algorithm 4an application methodology 5an accompanied software tool. The forthcoming challe...

A Real-Time Quality Assurance Tool for the Cyprus Construction Industry

Abstract Current economic crisis severely affected construction industry across the Globe. Major construction companies seek product differentiation through improved quality. However, Quality Assurance applied to the construction industry proves to be a challenging task since construction projects are highly customised constituting application of Statistical Process Control principles extremely difficult. Within this context, this paper presents the ongoing activities relating to the development of a real-time quality assurance tool for the Cyprus construction industry. The framework of this tool comprises of (a) a model of the construction process, (b) a list of construction processes, (c) a checklist and (d) an application methodology. Further work to the tool completion is also described.

Aquaculture Feed Management System Powered by Renewable Energy Sources: Investment Justification

Fish feed accounts for more than 50% of aquaculture farms’ operating costs and thus careful feeding planning is vital. In the case of the Mediterranean, most farms have their installations in coastal waters, hence this is relatively easy to perform. Low magnitude environmental conditions (winds, waves and currents) as well as easy and quick access ensures high consumption rates and smooth operation. Nevertheless, as competition for these waters increases the option of moving to offshore waters is seen as a solution. Moving further away from shore means exposing installations to harsher environments and lower degree of onshore monitoring. As a result, environmental conditions must now be monitored on-site, especially the ones affecting operations and feeding planning. For this reason, this article presents a feed management system powered by a stand-alone renewable energy sources system. The system provides energy independence and mobility by wirelessly transmitting important parameters onshore. An investment appraisal cost model is also described. The model compares the system’s costs over the fish feed cost saved by a priori feeding planning through better monitoring of on-site conditions. It concludes that such synergies have profitable potentials.

A new property of a class of Koornwinder Laguerre polynomials

A new property of a class of Koornwinders Laguerre polynomials is established. In this context, new classes of stable polynomials and polynomial pairs with real negative and interlacing roots are introduced. As a result, the distribution of zeros of a class of Mittag-Leffler functions is proved and new multiplier sequences are introduced.