Capitalismo tardio e ideologia: transformação qualitativa das formas de controle

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Imperialismo e educação do campo: uma análise das políticas educacionais no estado de Rondônia a partir de 1990

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Las tierras, los ganados, los trabajadores... Una posible reconstrucción de las estancias reduccionales de la experiencia jesuítica bonaerense, 1740-1752

El presente trabajo propone reconstruir el sistema productivo organizado por los misioneros de la Compañía de Jesús al sur de la jurisdicción colonial de Buenos Aires, entre 1740 y 1752. Si bien los hombres de la Compañía desarrollaron durante el siglo XVIII establecimientos productivos en todas las regiones rioplatenses, la característica de este caso se refiere a que la estancias y chacras que son descriptas tienen una vida activa de 12 años en la frontera, es decir, en territorio indígena ocupado por la reducciones pero con un dominio colonial no consolidado. Los espacios fronterizos no son habitados permanentemente por los españoles y la dominación y control del Estado suelen ser esporádicos. Por tanto, la experiencia misional se transforma en un mecanismo que pretende vigilar y controlar, pero que para existir en un territorio cuyo dominio es detentado por otras sociedades debe negociar con las mismas sus condiciones de existencia. ¿Cómo afectó esta situación a la constitución de ┤chacras' y ┤estancias' productivas? ¿En qué medida estos establecimientos se integraron a la red de establecimientos que la Compañía posee en tierras ┤españolas'? ¿La organización es similar en el ámbito fronterizo y en el ámbito ┤efectivamente' colonizado?

Las tierras, los ganados, los trabajadores... Una posible reconstrucción de las estancias reduccionales de la experiencia jesuítica bonaerense, 1740-1752

El presente trabajo propone reconstruir el sistema productivo organizado por los misioneros de la Compañía de Jesús al sur de la jurisdicción colonial de Buenos Aires, entre 1740 y 1752. Si bien los hombres de la Compañía desarrollaron durante el siglo XVIII establecimientos productivos en todas las regiones rioplatenses, la característica de este caso se refiere a que la estancias y chacras que son descriptas tienen una vida activa de 12 años en la frontera, es decir, en territorio indígena ocupado por la reducciones pero con un dominio colonial no consolidado. Los espacios fronterizos no son habitados permanentemente por los españoles y la dominación y control del Estado suelen ser esporádicos. Por tanto, la experiencia misional se transforma en un mecanismo que pretende vigilar y controlar, pero que para existir en un territorio cuyo dominio es detentado por otras sociedades debe negociar con las mismas sus condiciones de existencia. ¿Cómo afectó esta situación a la constitución de ┤chacras' y ┤estancias' productivas? ¿En qué medida estos establecimientos se integraron a la red de establecimientos que la Compañía posee en tierras ┤españolas'? ¿La organización es similar en el ámbito fronterizo y en el ámbito ┤efectivamente' colonizado?

Las tierras, los ganados, los trabajadores... Una posible reconstrucción de las estancias reduccionales de la experiencia jesuítica bonaerense, 1740-1752

El presente trabajo propone reconstruir el sistema productivo organizado por los misioneros de la Compañía de Jesús al sur de la jurisdicción colonial de Buenos Aires, entre 1740 y 1752. Si bien los hombres de la Compañía desarrollaron durante el siglo XVIII establecimientos productivos en todas las regiones rioplatenses, la característica de este caso se refiere a que la estancias y chacras que son descriptas tienen una vida activa de 12 años en la frontera, es decir, en territorio indígena ocupado por la reducciones pero con un dominio colonial no consolidado. Los espacios fronterizos no son habitados permanentemente por los españoles y la dominación y control del Estado suelen ser esporádicos. Por tanto, la experiencia misional se transforma en un mecanismo que pretende vigilar y controlar, pero que para existir en un territorio cuyo dominio es detentado por otras sociedades debe negociar con las mismas sus condiciones de existencia. ¿Cómo afectó esta situación a la constitución de ┤chacras' y ┤estancias' productivas? ¿En qué medida estos establecimientos se integraron a la red de establecimientos que la Compañía posee en tierras ┤españolas'? ¿La organización es similar en el ámbito fronterizo y en el ámbito ┤efectivamente' colonizado?

Control and protection of a microgrid with converter interfaced micro sources

This paper describes protection and control of a microgrid with converter interfaced micro sources. The proposed protection and control scheme consider both grid connected and autonomous operation of the microgrid. A protection scheme, capable of detecting faults effectively in both grid connected and islanded operations is proposed. The main challenge of the protection, due to current limiting state of the converters is overcome by using admittance relays. The relays operate according to the inverse time characteristic based on measured admittance of the line. The proposed scheme isolates the fault from both sides, while downstream side of the microgrid operates in islanding condition. Moreover faults can be detected in autonomous operation. In grid connected mode distributed generators (DG) supply the rated power while in absence of the grid, DGs share the entire power requirement proportional to rating based on output voltage angle droop control. The protection scheme ensures minimum load shedding with isolating the faulted network and DG control provides a smooth islanding and resynchronization operation. The efficacy of coordinated control and protection scheme has been validated through simulation for various operating conditions.

Protective behavior in adolescent friendships : the influence of attitudes toward the consequences, friendship norms and perceived control

The current study sought to understand adolescent protective behavior in friendship using a Theory of Planned Behavior framework. In particular, the study sought to consider a young persons’ direct and active intervention to inhibit their friends’ risky behavior or to assist them when the behavior leads to injury. The role of attitudes regarding the consequences, norms and control about protective behavior were examined both qualitatively through focus groups (n= 50) and quantitatively through surveys from a sample of 540 Year 9 students (13-14 years old). There was some support for the theory with attitudes regarding the consequences of the behavior and norms predicting intended protective behavior. A path analysis was conducted with a sub-sample of 140 students which showed that intentions to be protective and perceived control to undertake protective behavior directly predicted such behavior after a 3 month interval. Attitudes towards the consequences and norms only indirectly predicted protective behavior via intention. The findings provide important applied information for interventions designed to increase adolescent protective behavior in their friendships.

Dynamic Image-based visual servo control using centroid and optic flow features

This paper considers the question of designing a fully image-based visual servo control for a class of dynamic systems. The work is motivated by the ongoing development of image-based visual servo control of small aerial robotic vehicles. The kinematics and dynamics of a rigid-body dynamical system (such as a vehicle airframe) maneuvering over a flat target plane with observable features are expressed in terms of an unnormalized spherical centroid and an optic flow measurement. The image-plane dynamics with respect to force input are dependent on the height of the camera above the target plane. This dependence is compensated by introducing virtual height dynamics and adaptive estimation in the proposed control. A fully nonlinear adaptive control design is provided that ensures asymptotic stability of the closed-loop system for all feasible initial conditions. The choice of control gains is based on an analysis of the asymptotic dynamics of the system. Results from a realistic simulation are presented that demonstrate the performance of the closed-loop system. To the author's knowledge, this paper documents the first time that an image-based visual servo control has been proposed for a dynamic system using vision measurement for both position and velocity.

Poster : Understanding interactions between autonomous animal control and temperament when cattle are subjected to virtual fencing applications

Virtual fencing has the potential to control grazing livestock. Understanding and refi ning the cues that can alter behaviour is an integral part of autonomous animal control. A series of tests have been completed to explore the relationship between temperament and control. Prior to exposure to virtual fencing control the animals were scored for temperament using fl ight speed and a sociability index using contact logging devices. The behavioural response of 30, Belmont Red steers were observed for behavioural changes when presented with cues prior to receiving an electrical stimulation. A control and four treatments designed to interrupt the animal’s movement down an alley were tested. The treatments consisted of sound plus electrical stimulation, vibration plus electrical stimulation, a visual cue plus electrical stimulation and electrical stimulation by itself. The treatments were randomly applied to each animal over fi ve consecutive trials. A control treatment in which no cues were applied was used to establish a basal behavioural pattern. A trial was considered completed after each animal had been retained behind the cue barrier for at least 60 sec. All cues and electrical stimulation were manually applied from a laptop located on a portable 3.5 m tower located immediately outside the alley. The electric stimulation consisted of 1.0 Kv of electricity. Electric stimulation, sound and vibration along with the Global Position System (GPS) hardware to autonomously record the animal’s path within the alley were recorded every second.

What health services within rural communities tell us about Aboriginal people and Aboriginal health

There is a growing body of literature within social and cultural geography that explores notions of place, space, culture, race and identity. When health services in rural communities are explored using these notions, it can lead to multiple ways of understanding the cultural meanings inscribed within health services and how they can be embedded with an array of politics. For example, health services can often reflect the symbolic place that each individual holds within that rural community. Through the use of a rural health service case study, this paper will demonstrate how the physical sites and appearances of health services can act as social texts that convey messages of belonging and welcome, or exclusion and domination. They can also produce and reproduce power and control relations. In this way, they can influence the ways that Aboriginal people engage in health service environments – either as places where Aboriginal people feel welcome, comfortable, secure and culturally safe and happy to use the health service, or as places where they utilise the service provided with a great deal of effort, angst and energy. It is important to understand how these complex notions play out in rural communities if the health and wellbeing of Aboriginal people is going to be addressed.

Fold back current control and admittance protection scheme for a distribution network containing distributed generators

Islanded operation, protection, reclosing and arc extinguishing are some of the challenging issues related to the connection of converter interfaced distributed generators (DGs) into a distribution network. The isolation of upstream faults in grid connected mode and fault detection in islanded mode using overcurrent devices are difficult. In the event of an arc fault, all DGs must be disconnected in order to extinguish the arc. Otherwise, they will continue to feed the fault, thus sustaining the arc. However, the system reliability can be increased by maximising the DG connectivity to the system: therefore, the system protection scheme must ensure that only the faulted segment is removed from the feeder. This is true even in the case of a radial feeder as the DG can be connected at various points along the feeder. In this paper, a new relay scheme is proposed which, along with a novel current control strategy for converter interfaced DGs, can isolate permanent and temporary arc faults. The proposed protection and control scheme can even coordinate with reclosers. The results are validated through PSCAD/EMTDC simulation and MATLAB calculations.

Construction, application and validation of selection evaluation model (SEM) for intelligent HVAC control system

Design teams are confronted with the quandary of choosing apposite building control systems to suit the needs of particular intelligent building projects, due to the availability of innumerable ‘intelligent’ building products and a dearth of inclusive evaluation tools. This paper is organised to develop a model for facilitating the selection evaluation for intelligent HVAC control systems for commercial intelligent buildings. To achieve these objectives, systematic research activities have been conducted to first develop, test and refine the general conceptual model using consecutive surveys; then, to convert the developed conceptual framework into a practical model; and, finally, to evaluate the effectiveness of the model by means of expert validation. The results of the surveys are that ‘total energy use’ is perceived as the top selection criterion, followed by the‘system reliability and stability’, ‘operating and maintenance costs’, and ‘control of indoor humidity and temperature’. This research not only presents a systematic and structured approach to evaluate candidate intelligent HVAC control system against the critical selection criteria (CSC), but it also suggests a benchmark for the selection of one control system candidate against another.

Hybrid robot control and SLAM for persistent navigation and mapping

For a mobile robot to operate autonomously in real-world environments, it must have an effective control system and a navigation system capable of providing robust localization, path planning and path execution. In this paper we describe the work investigating synergies between mapping and control systems. We have integrated development of a control system for navigating mobile robots and a robot SLAM system. The control system is hybrid in nature and tightly coupled with the SLAM system; it uses a combination of high and low level deliberative and reactive control processes to perform obstacle avoidance, exploration, global navigation and recharging, and draws upon the map learning and localization capabilities of the SLAM system. The effectiveness of this hybrid, multi-level approach was evaluated in the context of a delivery robot scenario. Over a period of two weeks the robot performed 1143 delivery tasks to 11 different locations with only one delivery failure (from which it recovered), travelled a total distance of more than 40km, and recharged autonomously a total of 23 times. In this paper we describe the combined control and SLAM system and discuss insights gained from its successful application in a real-world context.

Geometric Control Theory and its Application to Underwater Vehicles

This dissertation is based on theoretical study and experiments which extend geometric control theory to practical applications within the field of ocean engineering. We present a method for path planning and control design for underwater vehicles by use of the architecture of differential geometry. In addition to the theoretical design of the trajectory and control strategy, we demonstrate the effectiveness of the method via the implementation onto a test-bed autonomous underwater vehicle. Bridging the gap between theory and application is the ultimate goal of control theory. Major developments have occurred recently in the field of geometric control which narrow this gap and which promote research linking theory and application. In particular, Riemannian and affine differential geometry have proven to be a very effective approach to the modeling of mechanical systems such as underwater vehicles. In this framework, the application of a kinematic reduction allows us to calculate control strategies for fully and under-actuated vehicles via kinematic decoupled motion planning. However, this method has not yet been extended to account for external forces such as dissipative viscous drag and buoyancy induced potentials acting on a submerged vehicle. To fully bridge the gap between theory and application, this dissertation addresses the extension of this geometric control design method to include such forces. We incorporate the hydrodynamic drag experienced by the vehicle by modifying the Levi-Civita affine connection and demonstrate a method for the compensation of potential forces experienced during a prescribed motion. We present the design method for multiple different missions and include experimental results which validate both the extension of the theory and the ability to implement control strategies designed through the use of geometric techniques. By use of the extension presented in this dissertation, the underwater vehicle application successfully demonstrates the applicability of geometric methods to design implementable motion planning solutions for complex mechanical systems having equal or fewer input forces than available degrees of freedom. Thus, we provide another tool with which to further increase the autonomy of underwater vehicles.

The role of vision in obese and normal-weight children's gait control

Previous research has suggested that perceptual-motor difficulties may account for obese children's lower motor competence; however, specific evidence is currently lacking. Therefore, this study examined the effect of altered visual conditions on spatiotemporal and kinematic gait parameters in obese versus normal-weight children. Thirty-two obese and normal-weight children (11.2 ± 1.5 years) walked barefoot on an instrumented walkway at constant self-selected speed during LIGHT and DARK conditions. Three-dimensional motion analysis was performed to calculate spatiotemporal parameters, as well as sagittal trunk segment and lower extremity joint angles at heel-strike and toe-off. Self-selected speed did not significantly differ between groups. In the DARK condition, all participants walked at a significantly slower speed, decreased stride length, and increased stride width. Without normal vision, obese children had a more pronounced increase in relative double support time compared to the normal-weight group, resulting in a significantly greater percentage of the gait cycle spent in stance. Walking in the DARK, both groups showed greater forward tilt of the trunk and restricted hip movement. All participants had increased knee flexion at heel-strike, as well as decreased knee extension and ankle plantarflexion at toe-off in the DARK condition. The removal of normal vision affected obese children's temporal gait pattern to a larger extent than that of normal-weight peers. Results suggest an increased dependency on vision in obese children to control locomotion. Next to the mechanical problem of moving excess mass, a different coupling between perception and action appears to be governing obese children's motor coordination and control.