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.
Today's the increasing globalization of the worldwide market and diverse technological advancements is forcing hard competition. Consequently, satisfying customers force firms to develop product and to look into all the possible areas of improvement in the product development process (PDP). The early research on PDP has produced models that view the process as a linear system with sequential and discrete stages. Over the time and with the increased complexity, PDP became hard to imagine out of Product Lifecycle Management (PLM) strategy. Hence, within the dynamic environment, managing a PDP is a challenging mission. In fact, uncertainty, variety, diversity, distributive control, interconnected entities are some of the factors that lead to the variation between expected and actual flows in PDP. Several disciplines have adopted the perspective of the Complex Adaptive System (CAS) as a viable alternative to an existing enterprise system to deal with such complexity. In this perspective, the present paper extends the linear, recursive and chaotic framework by considering PDP as a CAS. In addition, with using the complexity theory and especially an agent organizational methodology, the knowledge gained from this framework can be beneficial for PDP to move from isolated field to dynamic and holistic one.
Programmable Matter aims at developing new smart system consisting of a hardware component and a programmable approach allowing the adaptation of its physical properties to programmable inputs or autonomous sensing. Such a system requires a multidisciplinary approach bringing together material science, mechatronics and software programming. In this paper, a programmable and reusable shape memory based system is introduced that can be used for 4D prototyping. More precisely, this study proposes a device for the prototyping of product, allowing a modification of the geometry of the prototype by means of a deformable composite membrane with shape memory, reusable and programmable. The device consists of a flexible composite with a flexible polymer matrix and the reinforcement is a Shape memory alloys fiber and rubber effect, having a given electrical resistance. These shape memory fibers are woven in such a way as to ensure deformations in the direction normal to the plane of the membrane by injecting the current into each fiber. This is ensured by a cross weave allowing the control of the direction of the overall deformation through the deformation specific to each fiber. In this research, the results of the modeling and the simulation of the behavior of a composite membrane with shape memory are presented.
Some methodological foundations of effective construction of active media for innovative development are under consideration in the paper. The ideas of universal evolutionism, ecology understood in an extended sense, emergent properties of complex systems, time management, and the creating desirable futures turn to be useful here.
Graphlets, or induced motifs, have long been used to find important medium-scale structures in directed networks. We present a method using the composition of coloured graphlets in ego-networks to characterise nodes. We give an example application using our technique to predict the numbers of years researchers are active from their collaboration networks, and compare our success with simpler metrics; particularly, we find that the use of coloured graphlets improves predictive performance compared to colour-blind graphlets; that 4-star graphlets centred on an author are predictors of a long career, and that this effect is not degenerate to centralities.
Today, social media is a term that everyone knows. Even the most remote areas of the world have at least heard of Facebook and Twitter, and are probably using them on a regular basis. We live in a world where people publish and post everything they do or intend to do on social networks. And since we are interested in studying the opinions posted by the Moroccan Internauts, we were interested by learning this specific language they are using, a language that combines Latin letters with numbers, it is what we agreed to call the Moroccan sociolect language. I this paper we present the history of the linguistic situation in Morocco that gave birth to this Moroccan sociolect language, also we present a corpus we have build based on comments extracted from Facebook since it is the most used social media in Morocco. We also present the result of the application of the classifier of Bayes on this corpus with some propositions of improvement specific to this Moroccan sociolect language
The location routing problem combines location and routing decisions. Generally, the objective is to minimize the opening costs for the used depots, the fixed cost associated with the used vehicles and traveling costs spent in serving all customers. This paper presents a heuristic method permits to solve the capacitated location-routing problem (CLRP). A first phase executes a self-organizing map (SOM) to find the location of depots and assigning the customers to each depot. In a second phase, a Vehicle Routing Problem (VRP) is solved for each cluster using Sweep algorithm. Numerical results assess the higher performance of our method presented in this paper and demonstrate its efficiency in solving the instances with large size.
Orthogonal polynomial approach method has been extended in this paper to the modeling of a piezoelectric disc resonator in case of complete metallization with an excitation electrical source. This method makes use of Legendre polynomials series to express the mechanical displacement components and the electric potential which are introduced into the equations of motion of the piezoelectric structure. The formulation is founded on solving the Maxwell equations and three dimensional equations of linear elasticity coupled to the equation of motion. The principal advantage of this method consist of introducing, directly, the electrical source, the boundary and continuity conditions into the governing equations by the use of position-dependent physical constants and by a wise choice of the polynomial expansions for the independent variables, mechanical displacement components and electric potential. Both harmonic and modal analyses were studied, will have to define the resonance and anti-resonance frequencies, the input normalized electric admittance of the resonator disc, it is easy to implement for numerical calculation. A comparison of obtained results with analytical ones was provided.
This paper investigates first-level agenda-setting effects on Twitter during UK's EU referendum campaign. Using topic-modeling techniques, we investigate the dynamics of the interaction between users and the media content, and how the media outlets relate to each other. Results show that traditional media outlets dominated the debate, but alternative media played an important part. The media outlets that supported “Leave” stood closer to users' opinion who contributed to polarize the media's message, with pro-Leave side successfully framing some media's message in his own terms.
The main concern of power system managers is to ensure continuity of service while ensuring the quality of electricity supply. Power transformer equipped with On-Load Tap-Changer (OLTC) is the main component of electrical networks. On-Load Tap-Changer (OLTC) is one of the indispensable components for the regulation of power transformer used in electrical energy networks. In this work, we will study the maintenance of an acceptable voltage profile at the terminals of a power transformer by controlling its on-load tap-changer by a fuzzy logic controller.
Online social networks are growing rapidly, not only by the number of users they attract only, but also by the mass of data produced in a short period of time. Once created, they attract the other users attention who interact with it. The purpose of this study is to evaluate the impact of used keywords in the content attraction, through an analysis of the attractions different modes as well as the interactions natures of the different communities. and this for a crucial topic which is the environment and climate change. This paper looks at the keywords use in Twitter and its impact on the different users interactions of this complex system.
This paper deals with sensolress induction machine (IM) based on Extended Kalman Filter(EKF) for sensorless speed and stator resistance estimation using measured stator currents, stator voltages and estimated fluxes. As known, the use of a speed sensor to obtain speed, the rotor position or both increase highly sensitivity to electromagnetic noise and system complexity. The extended Kalman filter gives very high performances for the estimation of the speed at very low speed even with noises, thanks to two matrices Q and R which guarantee convergences of the speed and the stator resistance. Performances of the proposed EKF have been validated through Hardware implementation using Matlab/Simulink and dSPACE system with DS1104 controller board. The obtained results confirm very satisfying performances of the introduced EKF algorithm in term of dynamic performance.
SIMULINK users are constantly faced with the inability to analyze the dynamic behavior of electronic circuits that contain IGBT devices, using the semiconductor models of the SIMULINK library. These models represent only the static behavior. In this paper, a complete Electro-thermal model of the IGBT component for the SIMULINK simulator has been developed. The model based on a behavioral analysis, present the optimum compromise between accuracy and the capability to perform fairly complex simulation. The model parameter's can be quickly extracted from standard measurements or from data sheets.
The structures and functions of living systems are linked by scaling independent characteristics [1] and quantitative laws [2]. Systems merging into `Associations for the Reciprocal and Mutual Sharing of Advantages and Dis-Advantages' (ARMSADA) allows the emergence of new blueprints. Actors become together more and more mutually integrated into their new Whole and more and more independent from the previous situations [3]. Reversely the Whole is more and more integrating actors. According to the gauge invariance paradigm, not the Kleiber's law but another scaling invariance relation between actors is evidenced: a 2/3 exponent power-law. At every level of organisation, every living system is described with 4 dimensions: VA, the Adult system Volume, and tg, the time of generation, the duration that is necessary to acquire the reproduction capacity [4]. Considering the gauge invariance paradigm as a system, an analysis of a database of interactions allows to quantify 45×18 relations, from the quantum of Planck to the whole Universe, and a `grammar' of processes was evidenced: invariant processes (power laws with exponent € = 0), simultaneous limiting processes (€ = +1), feedbacks (€ = -1), competitions between actors (€ = 1/2) and optimal exchanges (€ = 2/3). The true process governing all functions is Brownian motion [5]. The regulation increase allows more and more autonomy. Living systems optimise input and output of matter and energy at the interfaces [6]. A greater diversity of processes occurs for throughput flows. Whatever the level, living systems optimise the survival by adjusting `the capacity to be hosted' of the endophysiotope (HOSTED) to the changes of `the hosting capacity' of the ecoexotope (HOSTING) [7] (Fig. 10).
The presented paper interested in the studies of the linear singular systems stability problem with two time varying delays via the Neutral approach in order to get a new stability criteria with a less conservative results. Firstly by transforming the singular system into a neutral one that allows to the compute to be more flexible. Then based on using the Lyapunov Krasovski and the Wirtinger-based integral inequality method the calculation of the derivative functionals will become simpler. The founded criteria will hold an LMIs on which the conditions will be generated that can be easily solved. In the end of this paper a numerical example is given to show the less conservatism of the stability of singular system with additive time varying results by using our proposed method.
In this paper a new four-dimensional chaotic system, with two quadratic, one cubic and one quartic nonlinearities is proposed. Basic dynamical characteristics of this new system are studied such as equilibrium points, Kaplan-York dimension, Lyapunov exponents spectrum and bifurcation diagrams by using either theoretical analysis or numerical methods. Then, an electronic circuit is implemented which validates the theoretical chaotic model of the proposed system. Finally, an active control synchronization is applied by considering two identical novel 4D systems.
