Abstract There is growing scientific and industrial interest in obtaining useful substances by fractionating lignocellulosic biomass from non-food plant crops for use the bioenergy industry. The primary goals are to ensure process sustainability comply with principles of circular economy. In this work, we optimized energy production Elephant grass previously using cold alkaline extraction remov...

The purpose of this work is to provide a complete study of the influence of operational parameters of the supercritical carbon dioxide assisted extraction (SC CO2E) on yield of wedelolactone from Wedelia calendulacea Less., and to find an optimal combination of factors that maximize the wedelolactone yield. In order to determine the optimal combination of the four factors viz. operating pressur...

Although gross domestic product (GDP) is not intended to be a measure of societal welfare, it is often used as such. One shortcoming as a welfare measure is that it fails to account for the non-marketed value of natural resource flows. The difference between societal welfare and GDP is labelled the ‘welfare gap’. A model that accounts for both market and non-market income flows from natural cap...

A fundamental problem in managing product development is the optimal timing, frequency, and fidelity of sequential testing activities that are carried out to evaluate novel product concepts and designs. In this paper, we develop a mathematical model that treats testing as an activity that generates information about technical and customer-need related problems. An analysis of the model results ...

We review an emerging application field to parabolic partial differential equations (PDEs), that’s economic growth theory. After a short presentation of concrete applications, we highlight the peculiarities of optimal control problems of parabolic PDEs with infinite time horizons. In particular, the heuristic application of the maximum principle to the latter leads to single out a serious illpo...

Astaxanthin is a novel carotenoid nutraceutical occurring in many crustaceans and red yeasts. It has exhibited various biological activities including prevention or amelioration of cardiovascular disease, gastric ulcer, hypertension, and diabetic nephropathy. In this study, ultrasound-assisted extraction was developed for the effective extraction of astaxanthin from Haematococcus pluvialis. Som...

Stochastic optimal growth involves the study of the optimal intertemporal allocation of capital and consumption in an economy where production is subject to random disturbances. The theory traces its roots to the seminal work on deterministic optimal growth by Ramsey [106], Cass [21] and Koopmans [55]. Its influence has been enhanced by research that shows how the convex stochastic growth model...

We explore the combined effects of a climate threshold (a potential ocean thermohaline circulation collapse), parameter uncertainty, and learning in an optimal economic growth model. Our analysis shows that significantly reducing carbon dioxide ðCO2Þ emissions may be justified to avoid or delay even small (and arguably realistic) damages from an uncertain and irreversible climate change—even wh...

The objective of this work is to design control strategies which optimize composition of production, technology stock and their rates in a nonlinear model of economic growth. The optimal control problem of R&D investment is formulated for a discounted utility function which correlates the amount of sales and production diversity. The maximum principle of Pontryagin is applied for designing opti...