The purpose of this article is to classify knowledge of the state of the art about intelligent cities and their various perspectives in which it has been discussed; a qualitative methodology is employed in the review process for the analysis of terms. Several definitions, dimensions and applications of the elements that integrate an intelligent city were located, being the common one in all intelligent cities the presence of the technologies of the information and communication, although it is a not unified concept similar characteristics were detected that look for to improve the quality of life of its inhabitants and the optimization of the resources that are in the city. The results obtained from the literary review show that intelligent cities are based on a model with different dimensions according to the conditions of the same, the implementation of such models tend in the future to generate characteristics such as social openness, stable economy, low unemployment rates, promote equality among citizens. Finally a model is proposed that arises from the literary revision, this model includes aspects like; Economy, environment, intelligent government, people and mobility as dimensions that can improve the quality of life of its inhabitants.

In recent years, quality in companies has become a priority issue which, according to the organization, is a matter of very little investment and dedication in the production lines, so a quality tool can be the solution to this problem. The present research work is to demonstrate the state of the art on Six Sigma and the perspectives in several industries through a bibliometric analysis using Bibliometrix. A database from Scopus is used, which includes a total of 857 articles in a time span from 2016 to 2020. From the results obtained, some characteristics of the articles are illustrated and analyzed (keywords, main authors, country of origin, main journals, scientific production and collaborative networks). The results obtained from the analysis show the existence of an exponential increase trend on Six sigma, being the basis for improving the quality of the processes.