The increasing demands of safety, cost reduction, or weight reduction on components call for new, multifunctional materials. Mechanical metamaterials, such as auxetic materials, provide enhanced properties due to a specially tailored microstructure. negative Poisson's ratio auxetics, instance, increases the impact and thermal shock resistance. Herein, parametrized model modified structure is si...

The electrophysiologic mechanisms for the initiation and termination of re-entrant ventricular arrhythmias (RVA) were critically analyzed in dogs 3-7 days following ligation of the anterior descending coronary artery, utilizing direct recordings of the re-entrant pathway (RP) from the epicardial surface of the infarction zone. Re-entry could occur during a regular cardiac rhythm if the heart ra...

The paper addresses the issue of stability for re-entrant flow lines, producing multiple products, with capacitated machines, random demand and random yield. The policies of interest are multi-echelon base stock policies, combined with a set of static and dynamic management rules of the available capacity. We introduce three classes of capacitated echelon base stock policies: Π0, the pure multi...

Re{entrant lines are manufacturing systems where parts may return more than once to the same machine, for repeated stages of processing. Examples of such systems are semiconductor manufacturing plants. We consider the problems of scheduling such systems to reduce manufacturing lead times, variations in the manufacturing lead times, or holding costs. We assume a deterministic model, which allows...

The simultaneous occurrence of atrial and ventricular tachycardias, or junctional and ventricular tachycardias, has been reported previously. We report on a patient presenting with syncope and demonstrating, simultaneously, atrioventricular re-entrant tachycardia and ventricular tachycardia of left origin. A left lateral concealed pathway was responsible for the former arrhythmia, while the lat...

We generalize the standard multi-class queueing network model by allowing both standard queues and infinite virtual queues which have infinite supply of work. We pose the general problem of finding policies which allow some of the nodes of the network to work with full utilization, and yet keep all the standard queues in the system stable. Towards this end we show that re-entrant lines, systems...

Superhydrophobic surfaces have many interesting applications because of their self-cleaning, waterproof, anti-biofouling, anti-corrosion, and low-adhesion properties. Accordingly, numerous with hierarchical micro/nanostructures are designed engineered to achieve superhydrophobicity. However, these two major problems. First, they lose superhydrophobic properties over time, primarily environmenta...

This paper presents a finite-element analysis of honeycomb and re-entrant honeycomb structures made of a two-phase composite material which is optimized with respect to selected parameters. It is shown that some distributions of each phase in the composite material result in the counter-intuitive mechanical behaviour of the structures. In particular, negative values of effective Poisson's ratio...