Soft-limiter circuit forms basis of simple AM modulator

Postprint (published version

El retardo del mensaje en sistemas de control distribuidos a través de Ethernet estándar

Gracias a su amplio ancho de banda, fiabilidad y reducido coste, la red Ethernet está invadiendo áreas de comunicación, en sistemas de control distribuidos,hasta ahora reservadas a otras redes específicas y/o propietarias. Sin embargo, este hecho obliga a evaluar cuidadosamente el retardo que sufren los mensajes con objeto de cumplir con los requisitos temporales exigidos en la aplicación. El presente documento aborda la modelización de este retardo, define sus principales componentes y, finalmente, recoge los resultados experimentales obtenidos y las diferencias respecto de los valores teóricos devueltos por modelo.Postprint (published version

Linear–assisted DC-DC switching converter with constant switching frequency

This article shows the proposal of a linear–assisted converter or linear–&–switching hybrid converter with a constant switching frequency. The control loop of the system is based on the current–mode technique. The main disadvantage of a converter with current–mode control is the inherent instability of the loop when switch duty ratios are greater than 0.5. In order to make stable the proposed linear–assisted converter, the article shows the technique based on a slope compensation.Postprint (published version

Parallel Linear–Assisted DC-DC Switching Converter

Linear-assisted DC-DC converters or linear-switching hybrid DC–DC converters are power supply structures in which some important advantages from linear regulators and DC-DC switching converters converge. Normally, in linear assisted converters a series linear regulator is used in order to provide a constant ripple-free output voltage. However, this article shows the proposal of a linear–assisted DCDC converter or linear–&–switching hybrid converter including a parallel linear regulator.Postprint (published version

Parallel linear-assisted DC-DC switching converter

Linear-assisted DC-DC converters or linear-switching hybrid DC–DC converters are power supply structures in which some important advantages from linear regulators and DC-DC switching converters converge. Normally, in linear assisted converters a series linear regulator is used in order to provide a constant ripple-free output voltage. However, this article shows the proposal of a linear–assisted DCDC converter or linear–&–switching hybrid converter including a parallel linear regulator.Postprint (published version

Current–Mode One-Cycle control applied to linear–assisted DC/DC converters

This article shows the proposal of an current-mode one-cycle control for linear-assisted DC/DC converters. Linear-assisted DC/DC converters are structures that allow to take advantages of the two classic alternatives in the design of power supply systems: voltage linear regulators (classic NPN topology or LDO –low dropout–) and switching DC/DC converters. The current-mode one-cycle control technique is proposed in order to obtain the duty cycle of the linear-assisted converter switch. The proposed structure can provide an output with suitable load and line regulations. The paper shows the design and simulation results of the proposed current-mode one-cycle linearassisted converter.Postprint (published version

Linear-assisted DC-DC switching converter with constant switching frequency

This article shows the proposal of a linear–assisted converter or linear–&–switching hybrid converter with a constant switching frequency. The control loop of the system is based on the current–mode technique. The main disadvantage of a converter with current–mode control is the inherent instability of the loop when switch duty ratios are greater than 0.5. In order to make stable the proposed linear–assisted converter, the article shows the technique based on a slope compensation.Postprint (published version

Distance Training in Robotic Applications Thanks to a Proposal of Remote Laboratory

This paper describes the development of a remote laboratory in the area of automatic and robotic engineering. The laboratory is based on an educational platform around a robotic arm that allows emulating a practical laboratory in which engineering students can corroborate their theoretical results comparing them with the real paths traced by the robot. Thus, the research work presented in the article is directed towards the consolidation of concepts in the field of robotics and control thanks to the use of the aforementioned remote laboratory.Postprint (published version

Current-mode one-cycle control applied to linear–assisted DC/DC converters

This article shows the proposal of an current-mode one-cycle control for linear-assisted DC/DC converters. Linear-assisted DC/DC converters are structures that allow to take advantages of the two classic alternatives in the design of power supply systems: voltage linear regulators (classic NPN topology or LDO –low dropout–) and switching DC/DC converters. The current-mode one-cycle control technique is proposed in order to obtain the duty cycle of the linear-assisted converter switch. The proposed structure can provide an output with suitable load and line regulations. The paper shows the design and simulation results of the proposed current-mode one-cycle linearassisted converter.Postprint (published version

Tecno-typological study of recent copper ceramics of los Castillejos (Montefrío, Granada)

En este trabajo se presentan los resultados obtenidos mediante la aplicación de difracción de rayos X y estereomicroscopía a las cerámicas halladas en las campañas de excavación realizadas entre los años 1991 y 1994 en los niveles del Cobre Reciente (2600-2000 cal. A.C) de Los Castillejos (Montefrío, Granada). Estas técnicas analíticas han permitido estudiar la producción cerámica de este yacimiento en el último momento de la Edad del Cobre, basándonos en la caracterización de sus pastas cerámicas, así como en la tipología de sus formas. A partir de nuestro estudio hemos podido determinar que las producciones son de carácter local, realizadas en su mayor parte con materias primas procedentes del entorno de Los Castillejos, cuyo proceso de manufactura denota cierta pericia por parte de los productores cerámicos, pese a que no se puede hablar de una sistematización de la fabricación cerámica debido a la escasa relación entre forma-tecnología.In this research work we present the results obtained through the application of X-ray diffraction and stereomicroscopy to the pottery found in the excavation campaigns carried out between 1991 and 1994 at the levels of Late Copper Age of Los Castillejos (Montefrío, Granada). These analytical techniques have allowed us to study the ceramic production of this deposit at the last moment of the Copper Age, based on the characterization of its ceramic pastes, as well as the typology of its forms. From our study we have been able to determine that the productions are of local character, made mostly with raw materials from the environment of Los Castillejos, whose manufacturing process denotes some skill by the craftsman, although it’s hard to confirm a systematization of ceramic manufacturing due to the poor relation between form-technology