Power System are complex, hardly nonlinear and unpredictable fault locations. Furthermore, separated power systems are interconnected to each other. As a consequence, in large interconnected power systems small signal stability, especially local and inter-area modes of oscillation, become an increasing importance and cause power system instability. The Power System Stabilizer (PSS) are introduced as supplementary signal in Automatic Voltage Regulator (AVR) to damp such oscillations. In this paper a comprehensive review on PSS are introduced.

Keywords: Power system stabilizer, fuzzy logic control, genetic algorithm, model reference model.

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[5]. J. H. Chow, G. E. Boukarim, and A. Murdoch" Power System Stabilizer as Undergraduate Control Design Project" IEEE Transactions on power systems, vol.19.1 February 2004, pp.144-151.

The objective of this research is to analyze the impacts generated by the volatility of returns in an investment project, through the discounted cash flow (DCF) methodology, which is exposed to financial risk. To do this, a hypothetical case was taken and with this case the financial valuation model of the project was developed, where the criteria of the net present value (NPV) and the internal rate of return (IRR) are evaluated; in a static and dynamic environment. The proposed model allows to perform the evaluation through the discount compound and continuous factor in the flow of benefits obtained throughout the time horizon. It also allows considering the value at risk of the returns using the mean - variance and normal delta modality, in order to guarantee greater reliability to investors in making decisions when investing their capital in the project. The model is very important because it offers, outside of the traditional evaluation, other alternatives that manage to identify the possible risk that can be obtained and the losses or benefits in investments, whether with or without financing.

Keywords: Valuation, financing, net present value, internal rate of return, value at risk.

[1]. Abellán, J. L. (12 de 2020). economipedia.com. Obtenido de https://economipedia.com/definiciones/capitalizacion-continua.html
[2]. AMBIT. (09 de 2020). AMBIT bst. Obtenido de https://www.ambit-bst.com/blog/retorno-de-la-inversi%C3%B3n-roi-qu%C3%A9-es-y-c%C3%B3mo-calcularlo

[3]. Chacur, M. G. (mayo de 2008). Horizontes empresariales . Obtenido de http://revistas.ubiobio.cl/index.php/HHEE/article/view/2047
[4]. Eppoliti, L. (8 de Enero de 2018). inbestME. Obtenido de https://www.inbestme.com/blog/desviacion-estandar-volatilidad-riesgo-movimientos-esperados-e-inesperados/
[5]. FINACOTECA. (2020). finacoteca.com. Obtenido de https://finacoteca.com/valoracion-de-inversiones-metodos-dinamicos-estaticos/

Manufacturing is the process of converting raw materials into products. The manufacturing process involves a series of activities of planning, design, procurement, production, inventory, marketing, distribution, sales and management. The requirements of the manufacturing process depend on the product offered by the company. These requirements, in terms of facilities, equipment, and production system contribute to the productivity of a company. Productivity is a measure of how efficiently the inputs are converted to outputs. Productivity improvement is a continuous process aimed at doing the right things better by constant improvement on the existing status. In this paper an analysis of the production process was carried out to determine the root cause of the prevailing productivity problem.......

Keywords: Manufacturing, Productivity, Productivity improvement, Root Cause Analysis

[1]. Cliff F. Grimes, 2008, Supervisors Guide to Productivity Improvement, www.accel-team.com
[2]. Dilanthi M.G.S., (2014) Improving Productivity with Maintenance Function in manufacturing Industry of Sri Lanka: Literature Review. International Journal of Education and Research, 1(4), 1-10
[3]. Jay H., Barry R., (2006) Operations Management, Pearson Education Inc., 1-22
[4]. Kongkiti Phusavat (2013). Productivity Management in an Organization: Measurement and Analysis, ToKnowPress. Bangkok, Celje,· Lublin
[5]. Mathew P. Stephens (2010), Productivity and Reliability – based maintenance Management