No abstract

No abstract

Accurate tuning of controller in industrial process operation is prerequisite to system smooth operation which directly reduce process variability, improved efficiency, reduced energy costs, and increased production rates. Performance evaluation of a model based PID controller tuning algorithm on a chemical process plant is presented in this paper. The control action of three different PID controller tuning algorithms namely; Hagglund-Astrom, Cohen and Coon, and Ziegler-Nichols on the process plant was examined in a closed loop control configuration under normal operating condition and in the face of disturbance. LabVIEW software was used to model a chemical process plant from open loop control test data. The time domain response analysis of the controllers shows that each tuning algorithm exhibit different time response. Ziegler-Nichols algorithm shows the best performance with fastest rise time, settling time and was able to restore the system back to normal operating condition in a short time when subjected to disturbance compare to Cohen & Coon controller and Hagglund-Astrom algorithm settings.

In this study, we introduce the UISpeech corpus which consists of Nigerian-Accented English audio-visual data. The corpus captures the linguistic diversity of Nigeria with data collected from nativespeakers of Yoruba, Hausa, Igbo, Tiv, Funali and others. The UISpeech corpus comprises isolated word recordings and read speech utterances. The new corpus is intended to provide a unique opportunity to apply and expand speech processing techniques to a limited resource language. Acoustic-phonetic differences between American English (AE) and Nigerian English (NE) are studied in terms of pronunciation variations, vowel locations in the formant space, and distances between AE-trained acoustic models and models adapted to NE. A strong impact of the AE-NE acoustic mismatch on automatic speech recognition (ASR) is observed. A combination of model adaptation and extension of AE lexicon for newly established NE pronunciation variants is shown to substantially improve performance of the AE-trained ASR system in the new NE task. This study represents the first step towards incorporating speech technology in Nigerian English.

This paper presents analyses of the model for the optimum design of standalone hybrid microgrid. The model is developed with the aim of optimizing system component sizing that can reliably satisfy isolated loads. The objective function is to minimize the annual cost of the plant while taking all constraints into consideration. Mixed integer linear programming technique is used to solve the optimization problem. By applying some approximations, the output power of the wind energy conversion system is expressed as a linear function of wind speed. Effects of different PV technologies and the rated power of each unit have been investigated. The results have shown the ability of the proposed model by reducing the cost of energy by 89.35%, 90.26%, 88.3530%, and 89.99% for AP120, ASE 300, KC120 and SAPC165 respectively. In the same way the carbon dioxide emission is reduced by 83%, 82.82%, 82.51% and 73.48 in the same order of the PV modules. Also, the optimal design is sensitive to the rated power of the WECS and SECS, while the benefit-to-cost ratio and payback period are sensitive to the storage technology.