We present a complete analysis of the MAX 2-SAT and MAX DI-CUT approximation algorithms of Feige and Goemans using various analytical and computational tools. By ne-tuning the rotation functions used we obtain minutely improved performance ratios for these problems. The rotation functions used for getting these improvements are essentially optimal as the performance ratios obtained using them a...

This paper presents an efficient distributed self-monitoring mechanism for a class of wireless sensor networks used for monitoring and surveillance. In these applications, it is important to monitor the health of the network of sensors itself for security reasons. This mechanism employs a novel two-phase timer scheme that exploits local coordination and active probing. Simulation results show t...

We explore the directed self-assembly (DSA) process of end-functionalized nanofibers (NFs) by performing coarse-grained molecular dynamics simulations. We find that by tuning their interactions, NFs aggregate and self-organize into networks with specific topologies ranging from percolated networks to liquid crystal-like long-chain phases. The underlying mechanism is explained through an analyti...

In process multi-input multi-output (MIMO) systems are observed that are dominated by interactions between input and outputs. Process decouplers are synthesized to reduce these interactions before controller design. In this work analytical expressions for closed-loop interactive transfer functions are found and interaction reducers (IR) are designed (as process decouplers) for closed-loop contr...

In the present paper, the possibility of generation of thin dense relativistic electron layers is shown using the analytical and numerical modeling of laser pulse interaction with ultra-thin layers. It was shown that the maximum electron energy can be gained by optimal tuning between the target width, intensity and laser pulse duration. The optimal parameters were obtained from a self-consisten...

Analytical solutions to the time-dependent, nonlinear equation governing incompressible, one dimensional flow in a pipe are presented. The flow is pressure-driven, and a valve on the pipe controls the flow rate. Power-law losses and an exponential closing action of a valve are assumed. Four different approximation methods are used. Of these, perturbation and Adomian’s decomposition are seen to ...

To overcome sluggish load disturbance response for industrial/chemical processes with slow time constant(s), an improved design for on-line autotuning of proportional-integral-derivative (PID) controller is proposed in this paper, based on relay identification of the widely used first-order-plus-deadtime (FOPDT) process model. Using the fitting conditions established for process response at the...

We show how the BLAS-like Library Instantiation Software (BLIS) framework, which provides a more detailed layering of the GotoBLAS (now maintained as OpenBLAS) implementation, allows one to analytically determine optimal tuning parameters for high-end instantiations of the matrix-matrix multiplication. This is of both practical and scientific importance, as it greatly reduces the development ef...

Intermodal terminals are important facilities in the container transport network, providing an exchange of containers between road and rail transport. Numerous factors can affect throughput in such highly integrated systems. These include numbers and types of equipment, physical layout, storage capacity and operating strategies. This study aims to improve operating strategies by developing an a...

Recent advances in the power of parallel computers have made them attractive for solving large computational problems. Scalable parallel programs are particularly well suited to Massively Parallel Processing (MPP) machines since the number of computations can be increased to match the available number of processors. Performance tuning can be particularly dii-cult for these applications since it...