The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The South African industrial sector is under significant financial pressure and need to reduce production costs to remain competitive in the global and local market. Some steel plants use reheating furnaces to reheat materials before hot rolling. These furnaces use industrial fuel gases as an energy source. Process by-product and purchased gases can be used as fuel. Inefficiencies in gas distribution...
Environmentally-friendly energy-efficient vehicles are an important contributor to meet future global transportation needs. To minimise the environmental impact of a vehicle throughout its entire life cycle, the life cycle energy optimisation (LCEO) methodology has been proposed. Using the proxy of life cycle energy, this methodology balances the energy consumption of vehicle production, operation...
With spreading of renewable energy in energy mix of national grids, the issue of high capacity and efficient energy storage is becoming very critical. A comprehensive model of South African power grid developed at the University of Pretoria is presented in this work. The model contains all notable power generators in the country. Mixed integer non-linear optimisation techniques are employed for unit...
The present work describes the production of the ultrapure water using Continuous Electro-deionization (CEDI) method. The CEDI unit consist of ion exchange membranes, Mixed Bed-12 (MB-12) ion exchange resin and electrodes to remove ion impurities from feed water. The product water from the RO unit is supplied to the CEDI unit. The Quality of the ultra-pure water is determined by the amount of ions...
In this paper a novel planning system for coils route optimisation among different processing steps of a generic steelmaking plant will be presented. This new approach, in addition to production times and costs, considers also customers' quality requirements. The system is based on Multi-Objective Optimisation and, in particular, it can exploit different paradigms of Multi-Objective Evolutionary Algorithms...
As a result of the increasing number of distributed energy resources (DER) in the electrical grid and their commitment to future market participation, control strategies for optimal operation of DER within microgrids gain importance. Ensuring a smooth, reliable and economic operation of a micro-grid, requires an energy management system that dynamically fits the consumption to the production in combination...
Mass customization plays a significant role for customer satisfaction and for reaching global markets in today's highly competitive changing world. However, customization brings companies extra costs because of the different tasks and scheduling and/or manufacturing issues of model variations. Companies in the manufacturing industry are in a pursuit of reducing their costs whilst increasing their...
This paper presents an improved algorithm for transmission expansion planning based on ant colony optimization, which is a heuristic optimization method showing several advantages compared to traditional methods. A grid model for the Nordic Area, Great Britain and a combination of both are used to show the performance of the optimization process. The focus of the work is to develop a tool for transmission...
This paper deals with the design of a nonlinear model predictive control (NMPC) scheme for the regulation of the substrate concentration in a lipase production bioprocess that takes place inside a Fed-batch Bioreactor. The NMPC control structure is based on the nonlinear model of the process whose parameters are known and all the states are measurable. Minimization of the cost function is realized...
Environmental concerns on the negative impact and depletion of fossil fuels have triggered a search for alternative energy sources. Biofuels are recognised as one of the most potential renewable alternatives. In order to have a sustainable production of biofuels, a processing facility (i.e., biorefinery) that converts biomass into value-added products is needed. As the first and second generations...
This paper presents a game theoretic multi-level optimization model that aims to control the international biofuel market, driving it towards the desired scenario. The resulting model gives an interpretation of the different scenarios that could face real world energy systems. The upper level decision maker, an international body, aims to maximize the total amount of biofuel that is locally produced...
This paper is a systematic theoretical study on the formation and development of urban spatial structure (USS) and New Towns. A dynamic simulation model of urban spatial structure evolution is presented in this paper. The model is characterized in terms of New Towns' endogenous, besides this, urban spatial evolution dynamics depends on the form of the urban market potential, which is described by...
Though the combination energy-saving measure for mechanical oil production well plays a very important role in improving the whole economic efficiency of the oil field, it does not reach to the optimal saving status. Except for the increasing inputs of saving measure, optimizing of the combination of kinds of saving equipment and technology is needed for enhancing the economic efficiency of the combination...
The microwave-assisted extraction of total Flavonoids from Solid wastes (Hawthorn seed) was optimized by response surface methodology. Important factors and their ranges were investigated using Plackett-Burman. Steepest ascent path was adopted to approach the optimal region, and then the Box-Behnken design and response surface analysis were used to determine the optimal levels of the main factors...
The low-cost activated carbon was prepared from sugarcane bagasse, an agricultural waste material, by chemical activation with different reagents. Orthogonal experimental design was applied to study the influence of activation temperature, activation time and chemical ratio of reagents to sugarcane bagasse on the chemical activation process of sugarcane bagasse. The optimal activated carbon was obtained...
In the frame of Intelligent Home project a data base of food products was created. Supposing that all of incoming and outgoing products will be detected through a RFID recognition, the developed expert system supports the optimization of food consumption in the household. The expert system applies the forward chaining or the backward chaining inference method in depend on current problem. The paper...
Multi objective multi contradiction task selection is an important and complex problem, and affects the benefit and the development of the enterprise remarkably. The mathematics mode of multi objective multi contradiction task selection problem is set up. The search method based on the elasticity is put forward. The mode and the method put forward are applied to solve two instances and optimal results...
A novel bio-inspired computational high-precision dental milling system is proposed in this interdisciplinar research. The system applies several bio-inspired models, based on unsupervised learning, that analyse and identify the most relevant features of high-precision dental-milling data sets and their internal structures. Finally, a supervised neural architecture and certain identification techniques...
In a high-mixed production environment, printed circuit board manufacturers face the challenge of frequent setups which involve rearranging the feeders on the machines. To reduce the setup cost, different boards can be assembled with a common feeder arrangement. This paper focuses on the optimization problems arising in this situation. Decisions are to be made on how different component feeders are...
Estimating the coefficients of objective functions in multi-objective model is sometimes difficult in real situations. Mathematical analysis of statistical data is used to determine the coefficients. In various cases, the statistical data may not contain only randomness, but also fuzziness, which should be treated properly. Thus, this paper employs fuzzy random regression model to approximate the...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.