The Nelder-Mead simplex method is an optimization routine that works well with irregular objective functions. For a function of n parameters, it compares the objective function at the n + 1 vertices of a simplex and updates the worst vertex through simplex search steps. However, a standard serial implementation can be prohibitively expensive for optimizations over a large number of parameters. ...

We consider the Nelder-Mead (NM) simplex algorithm for optimization of discrete-event stochastic simulation models. We propose new modifications of NM to reduce computational time and to improve quality of the estimated optimal solutions. Our means include utilizing past information of already seen solutions, expanding search space to their neighborhood and using adaptive sample sizes. We compa...

In many real world industrial situations, quality of a product is considered to be a composite of a family of properties or multiple responses, which can often be interacting or correlated with one another, and nearly always measured in a variety of units. Optimal combination of properties rarely results from individual optimal condition of each response, and there is always a trade off between...

The OMG’s Real-Time CORBA (RT-CORBA) and Fault-Tolerant CORBA (FT-CORBA) specifications make it possible for today’s CORBA implementations to exhibit either real-time or fault tolerance in isolation. While real-time requires a priori knowledge of the system’s temporal operation, fault tolerance necessarily deals with faults that occur unexpectedly, and with possibly unpredictable fault recovery...

We consider the Nelder and Mead Simplex Method for the optimization of stochastic simulation models. Existing and new adaptive extensions of the Nelder and Mead simplex method designed to improve the accuracy and consistency of the observed best point are studied. We compare the performance of the extensions on a small microsimulation model, as well as on ve test functions. We found that gradua...

Line-start permanent magnet synchronous motors (LSPMSMs) are of great interest to researchers because their high energy efficiency, due the growing manufacturers in energy-efficient units. However, LSPMSMs face some difficulties starting and synchronization processes. The LSPMSM lumped parameter model is applicable estimating successfulness further synchronization. parameters such a can be dete...

The Nelder-Mead algorithm can stagnate and converge to a non-optimal point, even for very simple problems. In this note we propose a test for sufficient decrease which, if passed for the entire iteration, will guarantee convergence of the Nelder-Mead iteration to a stationary point if the objective function is smooth. Failure of this condition is an indicator of potential stagnation. As a remed...

The active appearance models (AAM) are robust in face alignment. We use this method to analyze gesture and motions of faces in Human Machine Interfaces (HMI) for embedded systems (mobile phone, game console, PDA: Personal Digital Assistant). However these models are not only high memory consumer but also efficient especially when the aligning objects in the learning data base, which generate mo...

A 29-year-old man presented to the emergency department (ED) with a rash across his chest and abdomen. The rash began 2 hours before his arrival and was initially pruritic, but subsequently became painful. The patient also complained of acute onset of aching pain in both hips and his left arm. He denied associated chest pain or dyspnea, and had no paresthesias or disequilibrium. Routine laborat...

As animals vocalize, their vocal organ transforms motor commands into vocalizations for social communication. In birds, the physical mechanisms by which vocalizations are produced and controlled remain unresolved because of the extreme difficulty in obtaining in vivo measurements. Here, we introduce an ex vivo preparation of the avian vocal organ that allows simultaneous high-speed imaging, mus...