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Copyright of Revista Entramado is the property of Universidad Libre Seccional Cali and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The shape memory alloys are metals that belong to a class of shape-memory materials. These kinds of materials can memorize their previous form when they are subject to stimuli such as electric, magnetic, and thermic variations. The metal alloys that exhibit this characteristic are commonly named "muscle wires" because their main objective is to generate motion without electric motors or coils. Published studies have demonstrated that, in the case of the muscle wires, their durability and reliability can decrease due a material overheating as a consequence of overcurrent. The design of a buck converter based electric energy supply system for muscle wires is presented in this paper. A control stage based on fuzzy logic is included in the system to regulate the current through the muscle wire. The electrical current adaptation to a maximum magnitude, specified by the muscle wire manufacturer, is achieved in the presence of disturbances, according to the simulation results of the proposed system. [ABSTRACT FROM AUTHOR]

The restrictions of installed capacity and distribution resources to which medium and large manufacturing companies are normally subject, make it necessary to establish methods that serve as a tool to make decisions regarding the prioritization of each of their warehouses at the time of supplying them. the importance that the distribution center assigns to each of these, is closely related to the conditions and particularities that characterize them, being these factors of a qualitative, quantitative or a mixture between the two. This article presents a fuzzy QFD multi-criteria method which, in addition to using quantitative variables to establish the order of dispatch of the finished product, considers qualitative variables, the result of the opinions that experts can offer about the particular situations of each winery by means of linguistic variables that are finally quantified through fuzzy triangular numbers. [ABSTRACT FROM AUTHOR]

The control of the temperature of foods using cryogenic freezing equipment, becomes complicated when techniques of classical control as PID are used (Proportional + Integral + Derivative), due to the strong coupling between the variables and the non-linearities of the system. Currently, in most food processing plants that use tunnels of cryogenic freezing, the control is carried out through manual adjustments of set-points of control loops of the speed and temperature of the freezing tunnel, which results in deviations in the process output, derived mainly from the difference of criteria existing between operators and the response speed of them to variations in the process conditions. In this paper, we treat separately the control loops of speed and temperature, the current control loops are reconfigured and are intoned, and finally, is developed a Takagi-Sugeno fuzzy controller to adjust the set-point of the temperature of the freezing tunnel, in function of the product and the conditions of entry of food into the process. The behavior of the system is tested by its simulation, verifying that the system maintains the product temperature at -18 °C, regardless of changes in the product mass to cool (from 200 kg to 220 kg) and in the mass flow of the product (from 650 kg/h to 700 kg/h). [ABSTRACT FROM AUTHOR]

In this paper, a control architecture based on the reactive paradigm to solve the problem of autonomous navigation of mobile robots with limited computational capabilities and sensor system is presented. Stand out as the most significant contributions to this work, the encapsulation of a behavior-based control architecture in a programmable embedded system with limited processing capabilities and the use of fuzzy control theory in the implementation of a wall following behavior. Experimental tests were performed on a robotic platform equipped with three ultrasonic sensors and a wireless communication module. This module supports the 802.15.4 protocol in the ISM (Industrial, Scientific and Medical) band, through it sensory measures are transferred to a PC where computational representations of the explored environment are made. [ABSTRACT FROM AUTHOR]

In this paper a procedure for integration between production planning and maintenance planning, at the tactical level, is proposed. In its structure are integrated elements of Analysis of Value, Reliability Centered Maintenance and Fuzzy Control Theory, applied to an existing method for selecting maintenance strategies. The key outputs of the procedure consists in defining the roles of fixed assets that really add value to the production system, the best maintenance strategy for each asset and modifications, if necessary, in the tactical plan of production due to potential capacity problems in the maintenance subsystem. The implementation of this procedure was done partly, taking as practical study object a workshop of plastic items, being established for the main equipment the best maintenance strategy. [ABSTRACT FROM AUTHOR]

Decision making in science and technology is a complex task due to the multiple intervening factors. In the present paper a methodology for science and technology indicator analysis for organizational decision making purpose is presented. This methodology is based on the modeling of causal relations among indicators through fuzzy cognitive maps and its dynamics and statics analysis. For static analysis a node centrality composite indicator based on OWA operators is proposed. OWA operators based on distance are used to quantify scenario analysis. A case study is presented showing the proposal applicability. The methodology shows significant results for the application of fuzzy cognitive maps in science and technology decision making and policy conception. [ABSTRACT FROM AUTHOR]

The problem of autonomous navigation of small mobile robots in indoors is addressed. The proposed solution incorporates a behavior-based control architecture implemented through fuzzy logic, and a hierarchical scheme for behaviors coordination. This combination was tested in a small mobile robotic platform that has a ring with SRF02 sonars and a MCF51QE128 microcontroller resulting in a safe navigation of the environment at a low computational cost. [ABSTRACT FROM AUTHOR]

El control difuso de constitucionalidad es un medio de garantía del contenido del derecho más alto de un orden normativo, mismo que fue negado en nuestro ordenamiento jurídico por largo tiempo, a pesar de estar contemplado de forma literal en la Constitución. Por ello, en el presente documento se aborda el proceso hacia un nuevo paradigma que abre la puerta para que, mediante lo que se ha denominado control de convencionalidad, los jueces en México, independientemente de su nivel, puedan inaplicar disposiciones internas que contravengan disposiciones emanadas de tratados internacionales de derechos humanos que integran el bloque de constitucionalidad. [ABSTRACT FROM AUTHOR]

The curing process put indigo garment through certain conditions of temperature inside an oven to ensure its finish. This paper discusses through inductive method the design of a fuzzy logic control and PI control by the method of boundary gain for regulation of the variable temperature inside of a indigo garments curing oven from Expofaro Company, demonstrating the advantages of alternative controllers for regulation of industry variables. Additionally, the project has a wireless monitoring system which allows analyzing the behavior of the variable temperature throughout the curing oven. This work is done with embedded devices and electronic components, which achieved an appropriate functioning of the variable regulation, giving as a result proper adhesion of the resin onto the indigo clothes, achieving wanted breaks. The scope of the project includes the implementation of hardware and software to regulate the temperature of the oven. [ABSTRACT FROM AUTHOR]

This paper presents an initialization technique for a Simple Genetic Algorithm that tunes a Fuzzy Inference System working as a classifier. The proposed technique uses the Fuzzy C-Means (FCM) clustering algorithm to generate the initial population of a Simple Genetic Algorithm. Two classification problems are considered to validate the proposed algorithm and to compare it against a Simple Genetic Algorithm with random initialization. Results show that it is possible to achieve a reduction in generations necessary for finding a desired classifier by using the proposed technique. [ABSTRACT FROM AUTHOR]

The parking of a car in reverse is one of the situations that can bring more attention of any driver. The need to make the right decision, to make the parking lot quickly or slowly move in the direction wavelet and the corresponding angle, makes for drivers to exercise more care and greater skill. In the present work the approach, a fuzzy controller that allows the proper handling of a car in reverse. For this, we used as the basis of Matlab ® files to implement the fuzzy sets, fuzzy inference system and defuzzification that allow observing how a skilled worker could do the respective task [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an adaptive control scheme using the gain schedule method. The proposed approach uses a Sugeno-type planner to estimate online, the parameters of a digital PI controller. The experiment is realized on a motor-generator pair plant, in which the generation voltage is controlled with the regulation of the induced voltage in the motor. The performance of the proposed control system is evaluated against a conventional PI controller using error integral metrics. The results show a better performance over stability, disturbance rejection and transient response. [ABSTRACT FROM AUTHOR]

Copyright of Avances en Ciencias e Ingeniería is the property of Avances en Ciencias e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Universitaria is the property of Universidad de Guanajuato/Acta Universitaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Científica Guillermo de Ockham is the property of Revista Cientifica Guillermo de Ockham, Universidad de San Buenaventura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a vibration based fuzzy classifier used to detect fault conditions in bearings. The fuzzy knowledge foundation is obtained from the behavior of the vibration signal in presence of a fault condition in out-er race, inner race, cage and rolling element. The fuzzy system is implemented in Matlab® and it is validated in a vibration dedicate test bench used for research proposes. The system performance exhibits reliability and robustness in the fault detection in each experimental fault scenario. [ABSTRACT FROM AUTHOR]