A new sensorless method for switched reluctance motor drives

This paper describes a new method for indirect sensing of the rotor position in switched reluctance motors (SRMs) using pulse width modulation voltage control. The detection method uses the change of the derivative of the phase current to detect the position where a rotor pole and stator pole start to overlap, giving one position update per energy conversion. As no a priori knowledge of motor parameters is required (except for the numbers of stator and rotor poles), the method is applicable to most SRM topologies in a wide power and speed range and for several inverter topologies. The method allows modest closed-loop dynamic performance. To start up the motor, a feedforward stepping method is used which assures robust startup (even under load) from standstill to a predefined speed at which closed-loop sensorless operation can be applied. Experimental results demonstrate the robust functionality of the method with just one current sensor in the inverter, even with excitation overlap, and the sensorless operation improves with speed. The method is comparable to the back-EMF position estimation for brushless DC motors in principle, performance and cost. A detailed operation and implementation of this scheme is shown, together with steady-state and dynamic transient test results

The Italian Domatic Number of Varying Graph Families

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Wildland Fire Location Management System (WFLMS)

Wildland firefighters work in complex, dangerous environments where effective communication is key to developing situational awareness. Currently, the only communication firefighters have is with Very High Frequency (VHF) 160 MHz band analog radios. While digital radio protocols could potentially allow location data and commands to be sent to field crews, the technology is primarily for voice communication. This project presents a new system that frees up voice channels and uses LoRa transceivers for robust communication. The system allows for emergency and location reports to be sent to a dispatcher via an airborne repeater. The entire system is software-defined, so it can be updated as firefighter needs evolve

On the Robustness of Multidimensional Counting Poverty Orderings

Counting poverty measures have gained prominence in the analysis of multidimensional poverty in recent decades. Poverty orderings based on these measures typically depend on methodological choices regarding individual poverty functions, poverty cut-offs, and dimensional weights whose impact on poverty rankings is often not well understood. In this paper we propose new dominance conditions that allow the analyst to evaluate the robustness of poverty comparisons to those choices. These conditions provide an approach to evaluating the sensitivity of poverty orderings superior to the common approach of considering a restricted and arbitrary set of indices, cut-offs, and weights. The new criteria apply to a broad class of counting poverty measures widely used in empirical analysis of poverty in developed and developing countries including the multidimensional headcount and the adjusted headcount ratios. We illustrate these methods with an application to time-trends in poverty in Australia and cross-regional poverty in Peru. Our results highlight the potentially large sensitivity of poverty orderings based on counting measures and the importance of evaluating the robustness of results when performing poverty comparisons across time and regions

Evaluación de las asignaciones presupuestarias de proyectos de inversión pública del área urbana del cantón Riobamba y su incidencia en el desarrollo local, período 2015-2016/Evaluation of budget allocations for public investment projects in the urban are

Resumen El principal objetivo del presente ensayo es evaluar las asignaciones presupuestarias de los proyectos de inversión pública en el área urbana del Cantón Riobamba y su incidencia en el Desarrollo Local en el período 2015-2016, el presente trabajo de investigación fue correlacionar porque permitió conocer la relación o grado de asociación que existió entre la inversión pública, las asignaciones presupuestarias y el desarrollo local; a través de la aplicación de las variables de análisis estadístico: ANOVA y LEVENE; determinando así, cómo influyó esta relación de variables en mejorar la calidad de vida de la población considerando una correcta visión de desarrollo local en sus dimensiones: económica, social y territorial. De tal forma que se realice una revisión a la gestión realizada en la elaboración, ejecución y evaluación presupuestaria de los recursos económicos provistos por el Gobierno Local y Nacional; su uso, su beneficio y los resultados obtenidos, que permitan un aporte significativo en la evaluación de la inclusión de un adecuado modelo de ordenamiento territorial previsto a través de la Constitución y leyes vigentes para verificar que la ciudadanía se encuentre en un entorno ordenado, organizado y con acceso a un desarrollo local sostenible y sustentable en el tiempo. The main objective of this essay is to evaluate the budget allocations of public investment projects in the urban area of the Riobamba Canton and its impact on Local Development in the period 2015-2016, the present research work was correlated because it allowed to know the relationship or degree of association that existed between public investment, budget allocations and local development; through the application of statistical analysis variables: ANOVA and LEVENE; determining how this relationship of variables influenced to improve the quality of life of the population considering a correct vision of local development in its dimensions: economic, social and territorial. In such a way that a review is made of the management carried out in the preparation, execution and budgetary evaluation of the economic resources provided by the Local and National Government; its use, its benefit and the results obtained, which allow a significant contribution in the evaluation of the inclusion of an adequate model of territorial ordering foreseen through the Constitution and laws in force to verify that citizenship is in an orderly, organized environment and with access to sustainable local development that is sustainable over time. Palabras clave: Ordenamiento Territorial, Territorio, Presupuesto, Desarrollo Local, Evaluación. Keywords: Territorial Planning, Territory, Budget, Local Development, Evaluation

Campaign of aerodynamic measurements in a wind tunnel

2017/201

Photoinhibition of photosynthesis in natural assemblages of marine phytoplankton

A new empirical equation is introduced that describes the photosynthesis by phytoplankton as a single, continuous function of available light from the initial linear response through the photoinhibited range at the highest light levels liable to be encountered under any natural conditions. The properties of the curve are derived, and a procedure is given for fitting it to the results of light-saturation experiments for phytoplankton...