An economic-demographic dynamical system

2018 ◽  
Vol 13 (3) ◽  
pp. 27 ◽  
Author(s):  
A. Zincenko ◽  
S. Petrovskii ◽  
V. Volpert

Human population growth has been called the biggest issue the humanity faces in the 21st century, and although this statement is globally true, locally, many Western economies have been experiencing population decline. Europe is in fact homeland for population decline. By 2050 many large European economies are predicted to lose large parts of their population. In this work, we consider the dynamical system that corresponds to the model introduced by Volpert et al. [Nonlinear Anal. 159 (2017) 408–423]. With the help of this model, we illustrate scenarios that can lead, in the long-run, to sharp population decline and/or deterioration of the economy. We also illustrate that even when under certain conditions the population will go extinct, temporarily it might experience growth.

2017 ◽  
Vol 1 (4) ◽  
Author(s):  
Martin Brandt ◽  
Kjeld Rasmussen ◽  
Josep Peñuelas ◽  
Feng Tian ◽  
Guy Schurgers ◽  
...  

2018 ◽  
Author(s):  
Evan Jordan

As freshwater resource decreasing rapidly due to high rate of human population growth, many researchers have done studies to develop methods for producing freshwater supply. Seawater desalination is one of the method that has the credibility to be implemented. However, conventional seawater desalination processes suffer from a number of problems related to energy efficiency and cost. In spite of this, nanotechnology has been applied to the process. In this paper, we give an overview and explanations concerning the roles of nanotechnology in seawater desalination processes which consist of pretreatment, reverse osmosis (RO), and disinfection. In addition, the comparisons between conventional and nanotechnology-applied processes as related to its efficiency and effectiveness are also provided.


2014 ◽  
Vol 170 ◽  
pp. 311-320 ◽  
Author(s):  
Michelle L. Brown ◽  
Therese M. Donovan ◽  
W. Scott Schwenk ◽  
David M. Theobald

Sign in / Sign up

Export Citation Format

Share Document