Traffic flow in an urban area depends on several factors, which requires efficient control methods. In this paper, a dynamic control strategy of an urban signalized intersection is proposed. This strategy enables to manage the green light duration autonomously in accordance with the queue length for each lane. Every movement at the intersection is considered as a subsystem to be modeled separately and controlled (by traffic lights). The proposed control strategy allows managing the conflicts between phases, while reducing vehicles queuing time, decreasing the queuing length, and ensuring more safety. An isolated intersection is considered as a discrete event system, modeled by Petri nets. Some interesting properties of the system are checked through the developed Petri net model. To validate the proposed approach, SUMO based simulations are performed and analyzed. Through the performed simulations and analysis, the proposed dynamic control approach and obtained results show the efficiency of our control policy.
It is a fact that migration is a worrying problem in some world areas. Literature shows many studies about it. Nevertheless, no sound solutions have been proposed. Assuming that the key implied factors are development and demography, we suggest in this research, as a first step, to state a stochastic and dynamic demographic model neither considering sexes nor ages, but including the necessary and adequate economic, education and health variables. This model will be able to optimize, by means of a genetic algorithm, the amount and proportion of the main development indicators in different areas of the world along time, in order to reach the desired values of the population present in each area. The considered world areas are: Arab States, East Asia and the Pacific, Europe and Central Asia, Latin America and the Caribbean, South Asia, Sub-Saharan Africa, Middle East & North Africa, and North America. The input variables to be optimized (control variables) are those referred to health, education and economy (Life expectancy at birth, Adult Literacy Rate and Gross Enrolment ratio for primary to tertiary and Gross Domestic Product Income (GDP) per capita), per world areas. Demography rates such as Net Migration Rate, Birth Rate and Death Rate are calculated from these input variables. The necessary data to calibrate and validate the model come from the World Data Bank and the UNDP reports from 1990-2001 period and 2002-2012 period respectively. This paper presents optimized results for a specific zone in a specific period: Europe and Central Asia in the 2013-2030 period. They show that migration could be optimized in the future if the Human Development Index (HDI) increases in the eight considered zones, especially during the years 2013 to 2022. And the most significant increment has to be done in Arab States, Latin America and the Caribbean, Middle East & North Africa and Sub-Saharan Africa.
In this work, the focus is put on the issue of controlling a single-phase single stage Boost Inverter by an output feedback adaptive control. The main goal of this study is to provide a sinusoidal output voltage which follows tightly the desired reference. The considered control problem is permeated by many difficulties in terms of: (i) The nonlinearity of the studied circuit topology; (ii) The presence of the phenomenon of non-minimum phase makes the system difficult to control; (iii) Inaccessibility to measurements of all currents; (iiii) Unknown load. The issue is dealt using an indirect output voltage regulation: (i) An inner loop is designed using output feedback adaptive control based on the observer with a view to estimating the state variables (Currents); (ii) An outer loop regulates the output voltage to track its reference. The simulation outcomes have been corroborated within Matlab/Simulink/Simpowersystems, which demonstrate that the suggested controller achieves the desired aim.
In this paper, the (DFIG) for wind energy conversion system is studied so as to control the rotor speed and the reactive power produced by the (DFIG). To achieve these objectives, a decoupling control scheme has been applied utilizing PI controllers. In the DFIG topology, the stator is specifically associated with the grid and the rotor winding is associated with the grid through an AC/DC/AC converter. First, we propose the mathematical model in Park's coordinates of the whole system. Next, a field oriented control for decoupling the torque and the reactive power is applied. Finally, the DC Link voltage is regulated at a well defined constant value. This work is developed and programmed using Matlab/Simulink environment. The obtained simulation outcomes demonstrate the effectiveness of the suggested controller.
This paper presents a study related to feature extractors (detectors and descriptors) for V-SLAM applications. A review is performed with regards to well-known and optimized features descriptors like ORB, BRIEF, SURF, ZEON and bio-inspired descriptors like FREAK or HOOFR. Combinations with different widely used corner detectors like FAST, AGAST, STAR and SURF is also evaluated in terms of execution time resulting for both detection and description tasks. Results are analyzed to consider only the best combination for an automotive application. Evaluation results highlight the bio-inspired approaches considering the compromise between image processing accuracy and execution times.
