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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.
111

Att finna tonen : om satir i Marjaneh Bakhtiaris roman Kalla det vad fan du vill.

Henriksson, Linus January 2011 (has links)
Syftet med denna uppsats är att försöka finna vad som är kännetecknande för ett satiriskt framställningssätt, och sätta det i relation till det som jag ser som karakteristiskt för Marjaneh Bakhtiaris framställningssätt i romanen Kalla det vad fan du vill (2005). Numera ses satir som ett genreöverskridande begrepp som mer betecknar en ton eller ett förhållningssätt än en tydligt avgränsad genre. Det finns dock vissa återkommande kännetecken för vad som anses som satir, nämligen förekomsten av någon form av samtidskritik, komiska inslag och ironi. Vidare skildras även det satiriska verkets karaktärer i regel som typer eller karikatyrer och bibehåller sina karaktärsdrag genom berättelsens gång. Vid en analys av Kalla det vad fan du vill har jag funnit att Bakhtiaris framställningssätt i detta verk överlag stämmer väl överens med ovan beskrivna karaktärsdrag för satir. Dock finns det även några delar i verket där Bakhtiari väljer att frångå den satiriska tonen för vad som kan tolkas som en mer autentisk inriktad skildring.
112

Performance estimation of a ducted fan UAV

Eriksson, Mattias, Wedell, Björn January 2006 (has links)
The ducted fan UAV is an unmanned aerial vehicle consisting mainly of a propeller enclosed in a open ended tube. The UAV has the same basic functions as an ordinary helicopter UAV but has several advantages to the same. This thesis aims to estimate the performance of the concept of the ducted fan UAV. The company where this thesis has been written, DST Control AB, is currently investigating the economical possibilities to continue the development of this kind of UAV. This thesis shall provide DST Control AB with a theoretical as well as experimental ground for the investigation by estimation the lift capacity, position accuracy and wind tolerance. A ducted fan UAV prototype and a mathematical model for that UAV have been developed by DST Control AB and a student project at Linköping University. The model is constructed through pure physical modeling. Several noise sources have been added to better fit the reality. Several experiments have been conducted to validate the model with satisfying results. Experiments to determine the lift capacity of the craft have also been conducted. These experiments showed a slightly smaller lift capacity than the theoretically calculated lift capacity. The wind tolerance has not been tested in experiments because of the lack of available wind tunnels but simulations have given an estimation of this tolerance. To estimate the position accuracy, two different control systems have been implemented. The simplest control system is a system consisting of several PID controllers. The system is divided into two separate subsystems connected in cascade. The inner subsystem takes the pitch, roll and yaw angle as inputs and gives the rudder angles as outputs. The outer subsystem takes the inertial position as input and gives roll, pitch and yaw as outputs. Together, the two subsystems can be used to control the entire craft. The inner subsystem has also been replaced with a small LQ Compensator. An LQ Compensator for the entire system is also implemented giving about as good performance as the PID controller and better performance than the PID/LQ combination.
113

Developing an efficient FEM structural simulation of a fan blade off test in a turbofan jet engine

Husband, Jason Burkley 29 October 2007 (has links)
This work develops a methodology for full engine FEA simulation of the fan blade off containment test for a jet engine using LS-Dyna. The fan blade off containment test is a safety requirement involving the intentional release of a fan blade when the engine is running at full power. The released blade must not pierce or fracture the engine cases during the impact or rotating unbalance. The novel feature of the LS-Dyna simulation is the extensive full engine geometry as well as the widespread use of nonlinearities (mainly plasticity and friction) to absorb the large kinetic energies of the engine rotors. The methodology is simple to use, runs quickly and is being recognized by industry as a contender for widespread implementation. Future applications look promising enough that the methodology warrants further development and refinement.
114

A Sensorless Driver with Current Feedback for Three-Phase Brushless DC Fan Motor

Lin, Shih-Wei 18 October 2010 (has links)
The design and implementation of speed control driver which is applied to three-phase brushless DC fan motor are presented in this thesis. In the back-EMF detection circuit, we use digital filter circuits to obtain commutation to overcome the switch noises which are generated by high frequency PWM, without using traditional capacitor filter circuits which need more volume for additional external capacitor. Because the problems of high frequency magnetizing vibration and dispensable power consumption are generated by open-loop fixed frequency PWM speed control approach, closed-loop speed feedback control methods and closed-loop current feedback control methods are adopted to achieve high efficiency and low vibration of the fan motor drivers.
115

A Sensorless Driver with Current Feedback for Two-Phase Half-Wave Brushless DC Fan Motor

Kuo, Jhe-Gang 25 October 2010 (has links)
For energy conservation of sensorless two-phase half-wave brushless DC fan, this thesis develops a driver based on analogy circuits with current feedback control and speed feedback control. The main parts of the system include a sensorless start-up circuit, a sensorless commutation detection circuit, a speed feedback control circuit and a current feedback control circuit. Finally, we design experiments to compare it with outside PWM open-loop control and speed feedback control on experiment, the result shows that the driver with both current feedback control and speed feedback control displays better efficiency and lower vibration.
116

A Study of the Key Success Factors of Own Brand -- Case Study of DC-FAN Motor Driver ICs Market

Liu, Yu-Ming 31 July 2011 (has links)
Recently, the government makes good an environment and fully support to semiconductor industries from top to bottom covering the wafer foundry, IC design and equipment testing in Taiwan. Therefore, most of semiconductor brands which are very famous in the international. In early stages, Taiwanese electronic makers which were from OEM (Original Equipment Manufacturing, OEM) model to get resources, technologies and market information. They were became designers and have own R & D via the cooperation of international companies. And also got business form ODM (Original Design Manufacturing, ODM) to its own brand (Own Brand Manufacturing, OBM) direct management about the smile curve at both ends of the market to earn profits. In this study, Taiwan's IC design industry point of view of IC critical success factors of its own brand. In addition, to gathering in DC-FAN motor driving circuits in Taiwan. There are two related information of major leading brands for study. Through "qualitative research" in depth interviews of experts within the industry leader for the interview study, to find out its own brand of IC critical success factors. This research through the collation of expert interviews found that the market should impetus to fully service, increase innovative business models and strengthen integrated development of the semiconductor supply chains to get high techniques for next generation of products. And, to make good relationship with high position of customers that is critical success factors in its own brand. Moreover, it is a base of planning new products for the further. Hope, these findings could offer and give suggestion to industries as a reference. There is a model for reference when some one faces to similar situation.
117

¡¥Korean Wave¡¦ of Fan Culture: To Investigate the Interaction of Fans and Network Technology

Chen, Yen-li 21 October 2012 (has links)
K-pop throughout Asia and cause a new Korean wave in recent years, fans who adore K-pop idol has been gradually expanding and attracted much attention. You can see fans showing their fanatical behavior from the news reports. Fans use the Internet to quickly grasp the information, the e-community is the best platform for fans. Fan culture has become increasingly rich and diverse in the era of the Internet. This study tries to explore that fans how to interact with the Internet technology¡HAnd the Internet technology how to change the network relationship between the fans¡HIn this study, the data collected through participant observation and interviews with fans who adore K-pop idol. The result found that Internet is the best tools for fans, it can transmit and spread information. The Internet became a bridge which connecting fans around the world. Fans gathered together and collected resources to reach the goal, they also establish online identity based on their common e-community¡Bcommon experience instead of their background.
118

A Sensorless Speed Control Driver for Two-phase Half Wave Brushless DC Fan Motor

Chao, An-Li 18 July 2007 (has links)
The design and implementation of speed control driver, which is applied to two-phase brushless DC fan motor is presented in this thesis. In addition, motor coils current limiter, output-stage Snubber circuit, and lock detection and auto-restart circuit are added to the driver for the sake of increasing stability and robustness. Because of high frequency energizing noise and dispensable power consumption problems generated by open-loop fixed frequency PWM speed control approach, several closed-loop speed control methods with speed estimation signal feedback are adopted for improvement. Furthermore, this thesis proposes a sensorless driving control strategy to eliminate Hall sensor in rotor position detection, and similarly has closed-loop speed control methods to achieve the goal of driver cost reduction, size decrease, and good control performance.
119

Development of models for series and parallel fan variable air volume terminal units

Furr, James C., Jr 17 September 2007 (has links)
Empirical models of airflow output and power consumption were developed for series and parallel fan powered variable air volume terminal units at typical design pressure conditions. A testing procedure and experimental setup were developed to test sets of terminal units from three different manufacturers. Each set consisted of two series and two parallel units, each with 8 in. (203 mm) and 12 in. (304 mm) primary air inlets, for a total of four units in each set. Generalized models were developed for the series and parallel units, with coefficients varying by size and manufacturer. Statistical modeling utilized SAS software (2002). Fan power and airflow data were collected at downstream static pressures over a range from 0.1 to 0.5 in. w.g. (25 to 125 Pa) for the parallel terminal units. Downstream static pressure was held constant at 0.25 in. w.g. (62 Pa) for the series units. Upstream static pressures of all variable air volume (VAV) terminal units ranged from 0.1 to 2.0 in. w.g. (25 to 498 Pa). Data were collected at four different primary air damper positions. Data were also collected at four different terminal unit fan speeds, controlled by a silicon controlled rectifier (SCR). The models utilized the RMS voltage entering the terminal unit fan, the 'rake' sensor velocity pressure, and the downstream static pressure. In addition to the terminal unit airflow and power models, a model was developed to quantify air leakage in parallel terminal units, when the unit fan was off. In all but two of the VAV terminal units, the resulting models of airflow and power had R2 values greater than 0.90. In the two exceptions, there appeared to be manufacturing defects: either excessive air leakage or a faulty SCR that limited the effectiveness of the airflow and power models to capture the variation in the data.
120

An Analysis of Zeng Guaofan's Political and Military Administration with PAM and V.C.S.

Liu, Tsai-chin 12 June 2009 (has links)
This thesis is an analysis of the characteristics and the public affairs management policies of the traditional Chinese society during the reign of Emperors Xian-feng and Ton-gzhi in late Qing Dynasty. Using Tang Hao-ming¡¦s three-book trilogy Zeng, Guo-fan as the main reference, this thesis first analyzes the phenomenon, characteristics, and conditions of the traditional society during late Qing Dynasty with the PAM framework, and then follows Zeng, Guao-fan¡¦s career from the time when he first established the Xiang Army in 1852 to his passing in 1872 with V.C.S. analysis. His two-decades long service in public administration and the military, from his being drafted into the army while in mourning to his appointment as the Viceroy of Liangjiang, is divided into 22 stages. A comprehensive V.C.S. analysis of his four administrative periods is also provided. The last part of this paper consists of a PAM-based assessment of Zeng¡¦s administrative strategies, which can serve as valuable reference for promoting cross-strait social development and exchange. A viable strategy is also drawn from this historical period with the hope of resolving cross-strait conflicts and strengthening the ties.

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