This paper presents a new strategy to synthesis optimum controllable heat exchanger networks; the proposed strategy consists of four sequential steps: i) Quantification of index of structural controllability. ii) Exergy analysis and normalized irreversibility. iii) Thermal effectiveness of network. iv) Fuzzy analogical gates network and selection of the best weight index. Two analogical gates (...

Life extension of high cost components until measurable damage is detected can result in marked re ductions in total cycle costs. The life extension strategy for turbine disks is based upon nondestructive inspection to detect defects, usage and stress analysis to define requirements, and fracture mechanics analysis and testing to evaluate the severity of any defects under future usage. Because ...

Under conditions of limited fixed-nitrogen, some filamentous cyanobacteria develop a regular pattern of heterocyst cells that fix nitrogen for the remaining vegetative cells. We examine three different heterocyst placement strategies by quantitatively modelling filament growth while varying both external fixed-nitrogen and leakage from the filament. We find that there is an optimum heterocyst f...

We present a resource management algorithm based upon guided “walks” within a system state space. Walks are guided via simple predictions of optimum behavior whose accuracy increases as system state approaches a predicted optimum. Optimum behavior is defined as maximizing payoff, which is the difference between value of provided service and cost of providing the service. Feedback between predic...

Determining the optimum number of suppliers and the optimum quantities to order from each of them is a critical problem for any supply chain. This paper has mathematically arrived at conditions to identify the appropriate sourcing strategy in a multi-period scenario for a stochastic supply and a stochastic demand environment. It has also obtained the total order quantity, optimum number of supp...

With enhancing mixing in micro- or nanofluidic applications in mind, the problem of maximizing fluid transport across a fluid interface subject to an available energy budget is examined. The optimum cross-interface perturbing velocity is obtained explicitly in the time-periodic instance using an Euler-Lagrange constrained optimization approach. Numerical investigations which calculate transferr...

Efficient transmission of multimedia signals from energy limited portable devices requires a fresh look at the tradeoffs between source compression, channel coding and transmission strategies. In this paper we provide optimum operating points in terms of end-to-end source distortion and total energy consumption of the mobile due to compression, channel coding and transmission. We illustrate tha...

This paper examines methods of approximating the optimum checkpoint restart strategy for minimizing application run time on a system exhibiting Poisson single component failures. Two different models will be developed and compared. We will begin with a simplified cost function that yields a first-order model. Then we will derive a more complete cost function and demonstrate a perturbation solut...