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Once the wind data is measured, the values are processed, based on statistic approach, as accurately as possible, to provide a clear over-view of the locations wind potential, being the basis of any wind farm project, representing the go or no-go in further subsequent design steps. The probability density distributions are derived from time-series data, identifying the associated distributional parameters. The wind energy potential of the locations is studied based on the Rayleigh and Weibull models, implemented with the help of Excel computations, and representing tools, to understand the wind characteristics. Based on the statistical analysis of wind conditions presented here, the results of current study can be used to make a sustainable energy yield for any location.

Malaysia is not shielded from the issues of food insecurity. Despite economic progression over the past few years, food insecurity is continuing to affect several vulnerable groups (Orang Asli, elderly, students, B40). It is a growing concern that should not be taken lightly, especially with the recent rise in food prices coupled with low income among vulnerable groups and the effects of the COVID-19 pandemic. As cities develop and expand, they stretch out and occupy former farmlands forcing farms to stop operating or move further off from the city centre. New trends like urban farming are slowly emerging, which have the potential to be a solution to the developing crises of food insecurity. This research aims to determine how relevant each of the factors, ‘confidence’ (CF), ‘societal’ (SC), ‘pleasantness’ (PL), and ‘naturalness’ (NT), are towards adopting (AD) the idea of urban farming and, if relevant, among which has the most positive impact. A mixed-method approach was used to obtain quantitative and qualitative data. One hundred and thirty-three responses were recorded and used (a significant sample size according to the G-power software). The validity and reliability of the data were also tested to affirm their quality and relevance according to the factors. The main findings revealed that ‘pleasantness’ and ‘confidence’ were strong factors for adopting urban farming, in line with Cohen’s R Square of more than 32%, which signifies a high impact toward influencing adoption. In addition, qualitative analysis shows that while positive outcomes complemented the quantitative study, practical constraints were highlighted. These constraints were space, time, supply chain, resources, tools, community and government support. Hence, this study provides two significant contributions to regulators and policymakers on urban farming (further explained in the discussions section).

The main target of this paper is to develop and implement structures of fuzzy control in the continuous casting process (in the secondary cooling) capable of eliminating the surface flaws and casting rejects, to increase the quality of continuously cast products and implicitly to increase the productivity of the installation by controlling the water flow rate in the secondary cooling circuit. In order to achieve this objective, a solution will be developed and implemented, meant to control the casting process by a fuzzy system, allowing the control of the water flow rate in the secondary cooling, by appropriate distribution along the cooling area. This necessity is imposed by the fact that actual control systems do not correlate in real time the variations of the multiple variables related to the continuous casting process and stick to a rigid distribution of the water flow rate on each cooling area.

The present paper describes a neural network-based strategy for crack prediction aimed at improving the steel-casting process performance by decreasing the number of crack-generated failure cases. A neural system to estimate crack detection probability has been designed, implemented, tested and integrated into an adaptive control system. The neural system, consisting of two distinct neural networks, provides 0 or 1 probability values (1-high probability of crack occurrence, 0-low probability of crack occurrence). Also, a decision block, based on fuzzy logic (implementing an expert system), has been designed and implemented, triggering one or the other specific set of rules (according to 0 or 1 value of neural system) and tuning the set point of the control system.

The main target of this paper is to develop and implement structures of intelligent control of the continuous casting process (in the secondary cooling area) capable of eliminating the surface flaws and casting rejects, to increase the quality of continuously cast products and implicitly to increase the productivity of the installation by controlling the water flow rate in the secondary cooling circuit. In order to achieve this objective, a solution will be developed and implemented, meant to control the casting process by an intelligent fuzzy-type system, allowing the control of the water flow rate in the secondary cooling, by appropriate distribution along the cooling area. This necessity is imposed by the fact that actual control systems do not correlate in real time the variations of the multiple variables related to the continuous casting process and stick to a rigid distribution of the water flow rate on each cooling area.

In practice, vector control methods are widely used offering the possibility to reach high performance. Certain application areas need optimum control in at limit operating conditions, as, operation at maximum torque. The paper presents how through the proposed control scheme at the output of the flux and the voltage controllers, provide direct the frequency and voltage values for an asynchronous machine (ASM) operating at variable speed. The simulation analyses for the considered control structure are based on the use of two controllers: flux regulator for determining the stator flux and the speed regulator for determining the stator frequency. The dynamic analysis of the system is done highlighting the tuning process for the two controllers, which enables conclusions on the proposed method with different applications, as the ASM in wind turbines.

This paper aims at presenting how the RT 124 assembly developed by GUNT can be used in order to implement a fuzzy controller for a physical system consisting of an inverted pendulum mounted on a trolley. The model is a non-linear, one-dimensional, unstable MISO system with high demands consisting of real-time control, being intended for control using fuzzy logic. The paper goal is to create a fuzzy control system for maintaining the reverse pendulum in upright position with real-time control of the vehicle's position.

This paper presents the results of research based on real data taken from the installation process at Arcelor Mittal Hunedoara. Using Matlab Simulink an intelligent system is made that takes in data from the process and makes real time adjustments in the rate of flow of the cooling water and the speed of casting that eliminates fissures in the poured material from the secondary cooling of steel. Using Matlab Simulink simulation environment allowed for qualitative analysis for various real world situations. Thus, compared to the old method of approach for the problem of cracks forming in the crust of the steel in the continuous casting, this new method, proposed and developed, brings safety and precision in this complex process, thus removing any doubt on the existence or non-existence of cracks and takes the necessary steps to prevent and correct them.

The modern, developed society becomes aware of the necessity to conserve and protect the environment, increasing the gained benefits from a rational use of the natural resources. The pollution and the limitation of the fossil fuels, associated with the political situation worldwide that affects direct the energy strategies, have opened opportunities in the area of operation renewable energy sources. The development of the exploitation of renewable energy sources is directly linked to the energy politic, which, in terms of Romania, has the focus to integrate into the European Union energy strategy. The year 2014 brought in Romania many legislative changes to the renewable support scheme, that proves, once again, the legislative unpredictability and limitations introduced by the legislator "during the game" that overthrew all economic profitability calculation of the existent and planned investments in this sector. The actual stage of the wind energy across Europe and the particular situation in Romania are highlighted; also a 2020 forecast for Romania tries to evaluate the perspective for the wind, and general, renewable energy market. The actual Romanian renewable energy support scheme, mainly regulated by "Law 220/2008" ends December 2016. The so-called "ready to build" projects especially wind- or hydropower, can't be finalized until this deadline, being unable to qualify to the existing, mainly to inoperable, support scheme. Another legislation that has to clarify how investments in renewable energy will be supported is still not in place, blocking any project development, implementation and economical benefit of the producer. The paper presents in this respect an updated overview of the Romanian renewable energy sector and its perspective.

The paper introduces a fuzzy system meant to control the oxygen pressure and amperage of a CNC metal plate cutting machine. The fuzzy system control the oxygen pressure and the amperage by analyzing the plate thickness and type, which eliminates the possible human error in making such decision. The system was implemented using as hardware a Simatic S7-\300 PLC.

Vector control methods offer the possibility to gain high performance, being widely used. Certain applications require an optimum control in limit operating conditions, as, at maximum torque, that is not always satisfied. The paper presents how the voltage and the frequency for an asynchronous machine (ASM) operating at variable speed are determinate, with an accent on the method that keeps the rotor flux constant. The simulation analyses consider three load types: variable torque and speed, variable torque and constant speed, constant torque and variable speed. The final values of frequency and voltage are obtained through the proposed control schemes with one controller using the simulation language based on the Maple module. The dynamic analysis of the system is done for the case with P and PI controller and allows conclusions on the proposed method, which can have different applications, as the ASM in wind turbines.

This paper presents an intelligent system capable of eliminating the surface flaws and casting rejects, to increase the quality of continuously cast products and implicitly to increase the productivity of the installation.This method contains a fuzzy controller which requires changes of the water flow value at the secondary cooling. Fuzzy system controlling in real time the distribution of the water flow rate according to the real situation in the installation and working as an adaptive. The simulations results show us that the control strategy proposed is a very efficient method for the water flow control in the secondary cooling stage.

The main purpose of this paper consists in determining of the parameters which characterize the functioning of the Teves MK 60 as an ABS-ESP braking laboratory stand. This braking system model is used by the Volkswagen Golf and Bora the since 2002. The braking laboratory stand is able to simulate many operations which are able to give information concerning the ABS-ESP braking system comparing to the classical braking system. An application designed in LabVIEW comes to acquire and to process in real time the electrical signals generated by the Teves MK 60 laboratory stand.

This paper provides a modeling of the phenomenon of solidification and cooling of continuously cast semi-finished, based on the finite difference method. Also, to validate the model and conducted a simulation with “Tirsim” program. In the process of continuous casting, the melting pot is passed, through the intermediary of the distributor, in the water-cooled crystallizer tank. In this way, a crust forms here which is solidified at the exterior, and one of the great problems is its cracking or even it's tearing, due to several factors. This phenomenon determines the stopping of the technologic process and significant economic losses.

This paper proposes an adaptive fuzzy- system to eliminate sliding that may occur between the billets and rolls of drawing continuous casting steel plants. These slips may compromise the tuning speed of hardware caused by prediction system and crack elimination, the speed corrections are common and apply as a step. Design and production system are based on an original research of the authors.

The paper proposes a numerical model for the catenary suspension -pantograph assembly. With this model will be accomplished a control system for the contact force in order to rise the current collector quality and to reduce the energy loss.

Nowadays many control systems are able to control the continuous casting process by complying with all technological features. These systems do not consider all the causes of the factory rejects - semi-product crust cracks - which are extremely important for economical reasons. The continuous casting process referred in this paper is controlled by a complex system based on fuzzy logic and by individual PID regulators. This paper highlights the necessity for an upgraded control system in order to predict and remove the causes of any possible crack and presents a solution based on neural networks.

The paper introduces some experimental results of applying the theory of optimal control of high power reversible drives in a rolling mill from the steel plant of Hunedoara, Romania, starting year 2001. As the result of these experiments was a series of (predictable) conclusions that are drastically limiting the possibilities of a strictly optimal control, we suggested an expert structure meant to lead to favorable sub-optimal work conditions, which are achievable in practice.