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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.
141

Journalistic gender stereotyping of first ladies Laura Bush and Hillary Clinton

Wachai, James Njoroge 12 1900 (has links)
This study investigates media stereotyping of American First Ladies Laura Welch Bush and Hillary Rodham Clinton principally using quantitative and qualitative content analysis. The research explores the amount and qualities of Time magazine’s news coverage during their husband’s first terms of office to establish, (i) who between Mrs. Clinton and Mrs. Bush is framed as most often politically active and (ii) who between them is more negatively stereotyped. Hypotheses predict that the most politically active First Lady will attract more media coverage and more negative stereotypes. Both hypotheses were supported by the research, which indicate that Hillary Clinton was framed both as the most politically active and negatively stereotyped of the two. / Thesis (M.A.)--Wichita State University, College of Liberal Arts and Sciences, Elliott School of Communication. / "December 2005."
142

Effective medium theory and Rosseland mean opacity

Penley, Jonathan Jay 12 1900 (has links)
As a gas cools the mean opacity becomes dominated by the opacity of molecules and at low temperatures solid dust grains. Accurately computing the opacity is necessary to accurately compute the transfer of radiation through a gas. An attempt is made to refine the calculation of opacity within the stellar atmosphere modeling program PHOENIX through the addition of new optical constants, including those of the mineral species enstatite, forsterite, and fayalite. A general search for laboratory measurements of the optical constants of these minerals was performed, as well as a comparative study of the various data sets found. A study is also made investigating the importance of effective medium theory in the calculation of mean opacities within PHOENIX. Effective medium theory details the study of complex porous grains and the way in which they interact with electromagnetic radiation. The results of applying effective medium theory to modify the optical constants already within the bounds of this study are then compared to the current processes within PHOENIX. This study concludes that adding optical constants for forsterite and fayalite, and substituting a new data set for enstatite will help to improve the accuracy of PHOENIX models. Effective medium theory was found to not be a significant contributor to the calculations of the mean opacity. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Physics. / "December 2005."
143

Predicting recloser failure rates from field condition assessment

Warner, Joseph M 12 1900 (has links)
This research develops a technique to predict the failure rate of a power distribution system recloser. The prediction is based on suggested criterion given and defined within this paper. Because inspection practices differ among utilities, the technique will apply to whatever data is available, and make the best prediction from that data. Examples of using the technique are provided. Predicted failure rates can then be used in system simulations to predict system reliability indices, and the effect routine maintenance has on them. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering. / "December 2005."
144

Analysis of 3+2 point seat belt configuration and occupant responses in rollover crash of a pick-up truck

Marudhamuthu, Karthikeyan 12 1900 (has links)
This thesis studies the effectiveness of 3+2 Point Seat Belt system in making the car environment safer. The new and enhanced 3+2 Point Belt has conventional 3 Point Belt and an additional shoulder Belt conveyed from other side of the occupant. This provides additional pulling force of occupant towards Seat which minimizes him/her moving freely and hitting inside the vehicle compartment when the vehicle makes a roll of 45° or more. It also restrains the occupant from ejecting out of the vehicle. The test simulates the Rollover situation with the occupant secured by 3+2 or 3 Point Seat Belts. The rollover situation on a Dolly structure is modeled using Mathematical Dynamical Model (MADYMO) code with the use of Easi-Crash CAE software tool. The test simulation is produced by giving required velocities and accelerations to the vehicle in accordance to Dolly Rollover (FMVSS 208). The results are then compared and analyzed to validate the effectiveness of 3+2 Point Seat Belt over 3 Point Seat Belt. The main areas of interest of this thesis are: (a) Analysis of Occupant’s responses (Kinematics) from the MADYMO simulation; (b) Evaluation of effectiveness of the restraint systems like 3+2 and 3 Point Seat Belts in attenuating the injuries incurred by occupants; (c) Evaluation of injury factors like Head Injury Criteria, Acceleration, Nij values, etc. Hybrid III 50 th percentile male dummy is used to study the occupant responses. The MADYMO results for the Dolly Rollover test is analyzed by comparing the injury parameter standards and specifications of NHTSA. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering. / "December 2005."
145

LDPC encoded pilots for iterative receiver improvement

Hassan, Khurrum 12 1900 (has links)
Turbo and low density parity check (LDPC) codes show performances approaching Shannon capacity. This thesis proposes a novel iterative channel estimation and LDPC decoding scheme where the pilot symbols are encoded and can be used for both channel estimation and decoding using soft iterative receiver. To achieve this objective, systematic LDPC codes are employed so that pilot symbols can be encoded as data. In this way, initial channel estimation can be made before decoding by using the systematic coded pilot symbols. In addition, the known pilot symbol positions have higher reliability than data and can improve the initial decoding significantly. Using simulations it is shown that the decoding capability of the receiver improves significantly and ultimately LDPC decoder converges much early compared to the case where there are no coded pilots. Moreover, passing soft decoded values to the iterative receiver the coding gain improves also in comparison to the case when passing hard decoded values. (Abstract shortened by UMI.) / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering. / "December 2005."
146

Pre-shared key distribution protocol (PDP)-- FULL TEXT IS NOT AVAILABLE

Brahmadevula, Kiran Kumar 12 1900 (has links)
The proposed Pre-Shared Key Distribution Protocol (PDP) will distribute the IKE pre-shared key for IPSec between PDSN and HA in the 3GPP2 mobile networks. IPSec is used to provide security and integrity service between PDSN and HA. IKE is used for key exchange for the IPSec protocol. IKE can be configured to run either in pre-shared key mode or certificate mode to authenticate the identity of peers. There is a need for dynamic pre-shared key distribution protocol due to complexity and interoperability problems of IKE in certificate mode. Also the Public Key Infrastructure (PKI) required for the certificate mode is not available widely. Static pre-shared keys are not flexible to configure and easy to manage. The proposed key distribution protocol provides similar flexibility as certificates and is not prone to the interoperability and complexity problems inherent in PKI. The PDP protocol will eliminate the communication overhead and the number of packets dropped due to the expiration of the pre-shared keys. Also, it reduces the computation over head of pre shared key calculation as it is calculated only when needed. (Abstract shortened by UMI.) / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering. / "December 2005."
147

Distributed source coding using non binary LDPC

Potluri, Madhurima 12 1900 (has links)
In this thesis we have extended non binary low-density parity-check (LDPC) codes, developed for channel coding, to be used for source coding to compress correlated non binary sources. Focusing on the asymmetric case of compression of an equiprobable memoryless non binary source with side information at the decoder, the approach is based on viewing the correlation as a channel and applying the syndrome concept. The encoding and decoding procedures are explained in detail. The results obtained through simulations showed that the non binary compression scheme gives symbol error rates of zero for correlation coefficients greater than or equal to 0.80 for a compression rate of 1/2. For a compression rate of 3/4 the non binary compression scheme gives symbol error rates of zero for correlation coefficients greater than or equal to 0.65. In comparison the binary compression scheme gives bit error rates of zero for correlation coefficients greater than or equal to 0.90 for compression rate of 1/2. For compression rate of 3/4 the binary compression scheme gives bit error rates of zero for correlation coefficients greater than or equal to 0.75. This shows that the non binary compression scheme handles sources with relatively low correlations better than the binary scheme. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering. / "December 2005."
148

Statistical approach for predicting remaining life of crosslinked polyethylene insulated cables

Luitel, Mahesh 12 1900 (has links)
This study focuses on developing new remaining life model of the Cross linked polyethylene (XLPE) insulated medium voltage cables that are in use for hot and dry climate. Cross linked polyethylene insulating material degrades under the service condition acted upon by thermal and electrical stresses. Degradation of the materials is quantified by two main parameters Fourier Transform Infrared (FTIR) value and strength to withstand the electrical breakdown voltage. These parametric changes obtained by accelerated aging procedure developed with the help of Arrhenius Equation are tested for significance with that found in field aged cable with the help of statistical tools. Anderson-darling test for normality, Analysis of Variance (ANOVA), and one and two sample t-test were used to validate the lab aging procedure with field aging. New aging model, based on two parameters, Fourier Transform Infra Red (FTIR) spectrum value and Electric Breakdown voltage (EBV), was developed to quantify the current equivalent age of the cable and hence remaining life of the cable. The model is validated for different field aged cables in this study. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering. / "December 2005."
149

Propeller performance measurement for low Reynolds number unmanned aerial vehicle applications

Merchant, Monal Pankaj 12 1900 (has links)
The recent increase in the development of UAV’s and MAV’s has created a strong demand for small propeller performance data. Propeller performance is critical to the success of these aircraft and guaranteed performance demands accurate experimental data. These propellers operate at low Reynolds numbers (between 30,000 and 300,000), rendering performance scaling from larger counterparts inaccurate. An Integrated Propulsion Test System has been designed, developed and validated at Wichita State University to accurately and reliably measure performance of small propellers. Performance of a large number of propellers has been charted and a database of performance data has been created. This thesis discusses the salient features of this measurement system and data for a few of the, over 30 propellers, charted. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering. / "December 2005."
150

Service differentiation via cooperative MAC protocol (SD-MAC)

Tunc, Muharrem Ali 12 1900 (has links)
With the recent advances in wireless communications and networking area, it has been a great challenge for researchers to improve a medium access protocol for providing an efficient service differentiation in wireless ad hoc, sensor and wireless Local Area Networks among different priority class applications that require high goodput, short term fairness, low delay and delay jitter. IEEE 802.11 Static MAC protocol assigns different Arbitration Inter Frame Space (AIFS) durations for different priority classes to provide service differentiation. However, it is subject to a significant goodput degradation when the high priority class is low. On the other hand, IEEE 802.11e Dynamic MAC protocol employs different AIFSs, (CW min ,CW max ) pairs and contention window expansion factors (PFs) for different classes to support differentiated quality of service levels. Yet, it can not protect high priority class traffic from greedy sources in case of a heavy network load. The proposed protocol SD-MAC, Service Differentiation via CMAC, uses Cooperative MAC protocol (CMAC) as a basis protocol and can easily be implemented using IEEE 802.11e and CMAC. In SD-MAC, each node has to change its back-off counter based on both its own packet’s priority level and the priority level of the transmitted packet. If a node hears an ongoing transmission of a packet of higher priority than its own, it has to increase its back-off counter linearly. Besides, if it hears an ongoing transmission of a packet of lower priority than its own, it has to decrement its back-off counter exponentially. The simulation results indicate that, SD-MAC is a short term fair protocol which performs well in all network scenarios providing high network goodput, short term fairness and large admissible region. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering. / "December 2005."

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