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When the standard operating temperatures are exceeded in hydroxy generators, production performance decreases and power consumption increases. Self-adaptive fuzzy proportional integral derivative systems have been used to prevent this situation and to maintain optimum production conditions. The Fuzzy Logic is provided to tune the optimum PID parameters by using a gain scheduling method. The tuning scheme is demonstrated by a fuzzy decision process, which consists of fuzzification, knowledge and rule base, inference and defuzzification. Results of developed fuzzy proportional integral derivative (FPID), on-off, conventional PID and fuzzy control approach are discussed and compared. The presented result shows that self-adaptive fuzzy PID controllers achieve better control performance than conventional control methods mentioned. The last but not the least, developed approach minimizes the expertise needed to apply pulse width modulation technique. © 2020 Hydrogen Energy Publications LLC

9th International Conference on Hydrogen Production (ICH2P), WOS: 000466455000007, Software and hardware advancements on a hydroxy gas (HHO) production system is presented in this experimental study. A unique control system that enables to generate hydroxy gas at the specified volumetric flow rates with pulse width modulation (PWM) technique is developed and manufactured. The novelty of the method is automatic control of the hydroxy production according to the instantaneous demand, in other words, the adaptation of the HHO system to the operating principles of internal combustion engines (ICEs). A stepping motor represented the vehicle engine in order to get variable rotational speed values. The instantaneous rotation speed range of the motor divided into four sections as no rotation, low (1000-2001 rpm), middle (2001-4001 rpm) and high (>4001 rpm). A computer-driven microcontroller (MCU) card managed the entire system. The MCU card received motor speed input parameters and identified the PWM signal. Results of the study which are the electrical current, hydroxy gas flow and dry cell temperature ranges are presented in tables and graphs. The measured experimental data were 0-15 A, 0-1.56 L per minute and 24-48 degrees C for electrical current, hydroxy gas production and dry cell temperature ranges, respectively. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Summary The paper describes a set of modelling utilities (a root-zone model, a grid-distribution tool, and a modified Modflow-2000 model) that can be used to simulate the water cycle of a city in terms of root-zone water balance, water supply, wastewater, storm runoff, groundwater flow, streamflow, and the interactions between these subsystems. The utilities are used to simulate the water cycle in the Copenhagen area (976 km 2 ) during the period 1850–2003. Long-term time series of hydraulic head, streamflow, and inflow to sewage works have been used to manually calibrate the model parameters. We used a step-wise calibration strategy, using different parts of the data in the various steps, to calibrate hydrogeological parameters, storm runoff parameters, and parameters governing the interactions between groundwater and leaky pipe systems, respectively. Simulations indicate that present rates of groundwater leakage into streams, lakes, and wetlands constitute 60% of pre-urbanization levels due to massive groundwater extraction. However, the current problems of groundwater shortages and streamflow depletion would have been far worse, if precipitation had not increased by 20% since 1850. Model simulations indicate that urbanization has lowered current groundwater recharge due to the establishment of impervious areas and due to negligible contributions from leaky pipe systems. This is opposite to the reported general tendency of enhanced recharge due to urbanization. However, current recharge rates within Copenhagen are simulated to be 20% higher than prior to urbanization, which is attributed to the increase in precipitation during the study period.

In recent years Mali's economy has grown steadily at a rate of more than 5 percent per year, driven by developments in gold mining, cereal harvests, and telecommunications. Mali's landlocked condition, together with its very uneven distribution of both population and economic activities between the arid north and the much richer south, challenge the country's ability to sustain this pace of growth. These two aspects define and challenge Mali's development and the infrastructure agendas. The country's strategic focus on the regional agenda has paid off to date, and critical institutional decisions are bringing many positive developments. More than 80 percent of Mali's segments of the West Africa road corridors are maintained in good or fair condition, giving the principal production areas of the south alternative access to the deep-water ports of Dakar, Adidjan, Takoradi, Tema, and Lome. Air transport security has improved, supported by the refurbishment of local airports, including Bamako airport, and the restructuring of Mali's Civil Aviation Authority to increase its autonomy and guarantee harmonization of air transportation rules across West Africa. Mali has also successfully liberalized its mobile telephone markets, with access approaching 40 percent in 2008. Roaming agreements and cross country competition have kept mobile prices low. Access to electricity in Mali more than doubled in the last decade, helped by the introduction of an apparently successful program for rural electrification (AMADER) that widened access to more than 36,000 rural households.