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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Liderazgo directivo, caso Servicio Agrícola y Ganadero

Barredo Herrera, Fabiola Maritza January 2016 (has links)
Magíster en Gestión y Políticas Públicas / El estudio de caso se inserta en la problemática de la incidencia de las habilidades directivas en el sector público, como un factor relevante en el desempeño de unidades de trabajo en los órganos del Estado. El estudio de caso es una investigación aplicada a una oficina del Servicio Agrícola y Ganadero, en la que se produjo una situación de quiebre en las relaciones interpersonales entre el Jefe de la oficina y su equipo de trabajo durante el año 2012, la que fue superada con una intervención organizacional, de la que se obtuvo hallazgos de buenas prácticas factibles de ser consideradas en la gestión directiva a nivel de gobierno. En este estudio, se analizó por medio de entrevistas a los actores involucrados en la situación de quiebre, en las que se les pidió describir, y cuando fuese pertinente, entregar su explicación respecto tanto al episodio que desencadenó el plan de intervención como de los eventos previos, contemporáneos y posteriores a dicho episodio. Sobre la base de las respuestas de los entrevistados, se construyó un relato del proceso de superación de la situación de quiebre. El análisis del relato se vinculó con los aspectos conceptuales asociados a los hallazgos, y consecuentemente, se hicieron recomendaciones sobre la gestión directiva a nivel gubernamental. En el relato se detectó un aumento del nivel de estrés en los funcionarios de la oficina hasta llegar al punto de quiebre antes mencionado, momento en que se tomaron decisiones acertadas, para dar solución a la situación, logrando un cambio en el estilo de liderazgo, lo que no sólo permitió superar este quiebre, sino recuperar un equipo de trabajo comprometido y motivado, que a su vez se transformó en un ejemplo para otras oficinas sectoriales del SAG. El análisis conceptual de los principales hallazgos se centró en la generación de una actitud efectiva de liderazgo; mejora de la comunicación con el equipo de trabajo; desarrollo de habilidades de resolución de conflictos, uso efectivo de los resultados de encuesta de clima laboral; y el apoyo institucional. Si bien el caso estudiado es un hecho puntual, tanto las acciones realizadas como los respectivos efectos que acompañan al caso, son extrapolables a situaciones generales y replicables a otros equipos de trabajo del sector público.
2

Simulation of Stability Analysis for Distribution Systems with Dispersed Generation Using Matlab/Simulink

Huang, Kun-Cyuan 23 June 2005 (has links)
This thesis is to investigate the voltage sag, transient stability and operation feasibility of power islanding with different types of dispersed generation in distribution systems. One radial distribution feeder of Taiwan Power Company (TPC) is selected for computer simulation. The mathematical models of dispersed generations including exciters, governors of steam turbine and frequency controller of wind-driven induction generator are used in the simulation program of Matlab/Simulink. Applying the dispersed generation system with synchronous and induction generators at different locations of the test feeder by executing the short circuit and motor starting analysis to find the discrepancy in the voltage sag and the relation between the motor voltage with the motor power. Finally the simulation analysis of transient stability is executed for unbalance distribution systems with dispersed generations of steam turbines and wind-driven turbines by considering two different operation scenarios after the distribution system has been disconnected from TPC system. Different load and output power control of dispersed generation are applied to maintain the stable operation of the islanding power system. Based on the transient stability analysis, it is suggested that the service reliability of power system with critical loads can be enhanced by the dispersed power generation with proper design of load shedding and output power control.
3

The study on the singly moored offshore platform system

Li, Chun-yen 11 September 2006 (has links)
In this thesis, two-dimensional floating structure consists of single rectangular impermeable pontoon and single cable is studied.The purpose of this study is to obtain the motion analysis of incident waves acting on a floating with cable-restrained. All boundary conditions are linearlized in the problem which is separated into a scattering problem and radiation problem with unit motion amplitude. The method of separation of variable is used to solve for velocity potentials. Divide two kinds of discussions in cable-restrained¡G1¡BWith sag effective and flexural rigidity. 2¡BNO sag effective and no flexural rigidity. The boundary value problem with nonhomogeneous boundary condition beneath the structure is solved by using a solution procedure proposed by Lee(1995). By combining the scattering solution, radiation solutions of three degrees of freedom, and equations of motion of the floating structure, an analytic solution for the problem is developed.
4

Dynamic analysis of the cables consider Dynamic analysis of the cables consider sag effect and flexural rigidity

Chen, Wun-Shin 02 September 2005 (has links)
In this paper¡Athe cable structures considering sag effect and flexural rigidity are used to the series of dynamic analysis.It dedatees on vibration of the cables by the harmonic force and win¡Ðrain induced vibration. Using the finite element method to analyze the effect of the sge and the effect of the sag and the flexural rigidity¡Aincluding frequencies of the cable and displacement of every nodes at arbitrarily time.
5

A Voltage Sag Supporter Utilizing A PWM-Switched Autotransformer

Lee, Dong-Myung 12 April 2004 (has links)
This research suggests a novel voltage control scheme that can compensate for voltage sag and swell conditions in three-phase power systems. Faults occurring in power distribution systems or facilities in plants cause the voltage sag or swell. For sensitive loads, even voltage sags of short duration can cause serious problems in the entire system. In order to mitigate power interruptions, this research proposes a scheme called Voltage Sag Supporter utilizing a PWM (Pulse Width Modulation)-Switched Autotransformer. The proposed scheme is able to quickly recognize the voltage sag or swell condition, and it can correct the voltage by either boosting the input voltage during voltage sag events or reducing the input voltage during voltage swell events. Among existing methods, the scheme based on the inverter system such as dynamic voltage restorers (DVR) require an inverter, a rectifier, and a step-up down transformer, which makes the system expensive. AC converters can be used for the purpose of the research. However, they consist of two solid-state switches per one phase and include energy storage devices such as reactors and capacitors. The switching device for the high voltage application is relatively expensive so that this research suggests a scheme utilizing only one switch for the output voltage control, which makes the system more stable and cost effective. The proposed scheme can be applied at any voltage and provides cost and size advantages over existing methods due to the reduced number of switching components and no need of energy storage devices. Simulations and experiments have been carried out to verify the validity of the proposed scheme, and prototype experiments are being done to confirm the control scheme.
6

Voltage Sag Measurements for Service Performance Assessment and Fault Location Identification

Shen, Hung-Yuan 26 July 2005 (has links)
Abstract This thesis summarizes some of the voltage sag indices that are currently used by the industry. Power quality monitoring results obtained at two science based industrial parks are used to estimate the voltage quality of the electricity service and make comparison with data of a foreign utility company that are available in the literature. Fault position method is used in this study to estimate the distribution of voltage sag vulnerability areas due to the network topology ok in 2005. Comparison of the exposed area is presented. An assessment is conducted for the application of fault position method to estimate the fault location by using fault simulations results and power quality monitoring data.
7

Effect of Voltage Sags on Sensitive Equipment

Chen, Zhi-Qiang 28 July 2005 (has links)
Voltage sags are short duration of voltage reduction caused by system faults, overloads and starting of large motors. Voltage sags are the main causes of trips of various sensitive equipment. In order to understand the voltage-tolerance performance of some process control equipment, this thesis presents test results of some sensitive equipment (such as computers, AC contactors, high intensity discharge lamps and programmable logic controller) and provides their voltage tolerance curves. A number of magnitudes and durations recommended by IEC 61000- 4- 11 are used to perform the tests. With the performance information in hands, power quality requirements of different types of equipment and customer, and area of vulnerability for sensitive loads could be estimated.
8

Effect of Voltage Sags on Adjustable-Speed AC Drives

Tseng, Tao-Ping 02 September 2006 (has links)
Adjustable-speed drives (ASDs) are often used in commercial and industrial facilities to improve process control and save energy. However, ASDs are the sensitive load equipment as regards to voltage sag. During the sag, the dc-bus capacitor of a typical ASD will discharge depending on the loading condition. The voltage of the dc bus decreases and could lead to a trip of the device. In order to understand the voltage sag tolerance capability of ASDs. Based on IEC 61800-3 and IEC 61000-4-11, this research presents the test results of ASD subjected to voltage sags under different operating conditions. The tests focus on different types of voltage sags, operating situations and designs of ASDs.
9

The impact of modern headlamps on the design of sag vertical curves

Gogula, Madhuri 16 August 2006 (has links)
Incorporating safety in the design of a highway is one of the foremost duties of a design engineer. Design guidelines provide standards that help engineers include safety in the design of various geometric features. However, design guidelines are not frequently revised and do not accommodate for the frequent changes in vehicle design. One such example is the change in vehicle headlamps. These changes significantly impact the illuminance provided on the road and in turn the design formula. Roadway visibility is critical for nighttime driving. In the absence of roadway lighting, vehicle headlamps illuminate the road ahead of a vehicle. Sag vertical curve design depends on the available headlight sight distance provided by the 1 degree upward diverging headlamp beam. The sag curve design formulas were developed in the early 1940s when sealed beam headlamps were predominant. However, headlamps have changed significantly and modern headlamps project less light above the horizontal axis. In this research, the difference in illuminance provided by sealed beam headlamps and modern headlamps was examined. For the theoretical analysis, three different sag curves were analyzed. On these curves, about 26 percent reduction in illuminance was observed at a distance equal to the stopping sight distance when comparing sealed beam to modern headlamps. A change in the headlamp divergence angle from 1.0 degree to 0.85 degree will provide the required illuminance on the road when using modern headlamps. A field study was performed to validate the theoretical calculations. It was observed that for modern headlamps, a divergence angle less than 1 degree and greater than 0.5 degrees will provide illuminance values comparable to sealed beam headlamps. As a part of this research, a preliminary study, examining the impact of degraded headlamp lenses on the illuminance provided on sag vertical curves was conducted. A significant reduction in illuminance reaching the roadway on sag curves was observed, due to headlamp lens degradation.
10

Įtampos trūkių ir krypčių sukeltų nuostolių pramonės ir komercijos įmonėse tyrimas / The research on the damage of the sags and the dips of the voltage to concerns of the industry and commerce

Linkus, Raimondas 16 June 2004 (has links)
The theme of Master project of Energetics engineer is to analyze the damage of the sags and the dips of the voltage to going concerns, to find the ways of avoiding the sags and the dips of the voltage and to improve the quality of the electric power. The graphs which are included show the sags and the dips of the voltage. Some of the ways to avoid it are included also. An example introduces the best way how to supply the electric power without the sags and the dips of it.

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