41 |
Dynamic voice codec determination mechanism for VoIPOsipov, Andrey E. 05 1900 (has links)
Emerging voice over IP networks dictate a need for efficient network resource management schemes to mitigate the best-effort nature of IP. Traditional quality of service and call admission control mechanisms provide network resource allocation to static voice flows with parameters fixed by a selected voice codec. Frequently, the available bandwidth is not efficiently utilized, which results in a lower-than-possible average voice quality and potential wastage of resources. In this thesis, the author proposes a dynamic voice codec determination scheme that selects codec’s on per-call basis with respect to available resources. The proposed mechanism relies on continuous monitoring of a centrally managed IP network to determine the best voice codec selections for each pair of participating voice gateways. The determination process is modeled as a simple knapsack-like problem to take the fullest advantage of available resources, while maximizing the average voice quality. Overall, the new system is shown to achieve a better average voice quality and more efficient network resource utilization, when compared to traditional application centric QoS and all admission control solutions. / Thesis (M.S.)--Wichita State University, Electrical and Computer Engineering. / "May 2006." / Includes bibliographic references (leaves 60-63)
|
42 |
Design and analysis of a composite beam for side-impact protection of occupants in a sedanSheshadri, Ashwin 05 1900 (has links)
Occupant safety in automobiles over the last few decades has become a very important research area where in continuous developments to improve is proposed everyday. New standards are set in pertinent to different crash scenarios such as the frontal crash, side impact, angled impact and so on. Among these standards, side impact is one of the fatal crash scenarios that lead to death of scores of people in the United States and across the globe. Side Impact beams are used in the doors to help protect the occupant being the victim of a crash. In the contemporary world, fuel consumption also poses a serious issue that has to be considered. With these constraints in consideration, a lighter and stronger material than steel, the composite material, can be used in the side door. Using this material would help in reducing the fuel efficiency without sacrificing the safety of the vehicle. In this research, a composite side impact beam is designed to replace the present beam and the injuries sustained by the occupant are recorded. An attempt is made to use Carbon/Epoxy and Glass fiber/epoxy composite materials in the beam designed in this study. In addition, a parametric study is carried out on the beam to determine the maximum possible energy absorbing parameters. It is demonstrated that the new design with the use of carbon/epoxy with a pertinent orientation and thickness may present more energy absorption than the present steel beam. Energy absorption, displacement and the acceleration of the present and the new design are also compared and discussed in detail. Occupant injuries, such as chest and head injuries are compared for the vehicle occupants with present and the new designed beam. It is demonstrated that the new designed composite beam with carbon/epoxy may be more effective than the present steel beam. With the advance in computer simulations, finite element (FE) model of the Ford Taurus and Moving Deformable Barrier (MDB) developed by the National Crash Analysis Center (NCAC) has been used for different impact scenarios to predict the vehicle behavior and occupant response. In addition, MSC Patran has been used as the modeler and LS-Dyna as the solver to run the required simulations. MADYMO is used to predict the injury parameters. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering / "May 2006." / Includes bibliographic references (leaves 121-123)
|
43 |
Application of stochastic control and robust stability of singularly perturbed unified systemsKim, Dongwook 05 1900 (has links)
The unified approach and singular perturbation theories are two of the most highly recognized and rapidly developed areas in the control field recently. In this thesis, a stochastic optimal controller design using state feedback is examined for singularly perturbed unified systems with Gaussian noise. The difference between the costs of full order systems and those of reduced order systems is just on the order of epsilon. The robust of a singularly perturbed unified stochastic system is investigated by exploring stability bounds under system uncertainties. A new unified stochastic bound is imported for the investigation. Practical application illustrates the validation of the concepts. / Thesis (M.S.)--Wichita State University, Dept. of Electrical Engineering. / "May 2006." / Includes bibliographic references (leaves 50-53)
|
44 |
Asymptotic fusion performance in a power constrained, distributed wireless sensor networkAl-Tarazi, Kossai Abdalah 05 1900 (has links)
The performance of decentralized detection in power constrained wireless sensor network is analyzed. We consider two distributed processing schemes; the analog relay amplifier local processing and the quantized decision local processing. In the first model, the system is assumed to be subjected to a total power constraint and the distributed nodes are assumed to perform analog relay amplifier local processing. Under these assumptions, we show that, we can monotonically improve the fusion performance by using non-orthogonal sensor-to-fusion center communication, as opposed to orthogonal communication. In order to quantify the performance, we employ circulant matrix theory to derive closed form asymptotic expressions. These asymptotic results allow us to observe the effect of each parameter on the total system performance. Numerical results show that these asymptotics provide a very good approximation to the exact performance, even for a small number of sensors. In the second model, distributed nodes are assumed to make binary decisions, in an inhomogeneous sensor system. i.e. the channel statistics are not identical among the sensors. We derive the asymptotic fusion performance via the Lindberg-Feller central limit theorem. A power allocation scheme is also proposed based on the well-known water-filling algorithm. The proposed scheme shows better performance corresponds to the equal power assignment when the total power is sufficient with respect to the network size. However, as we increase the network size the water-filling gain diminishes. / Thesis (M.S.)--Wichita State University, Dept. of Electrical and Computer Engineering. / "May 2006."
|
45 |
Bored to death: William Inge’s women and The feminine mystiqueUnruh, Kendra 05 1900 (has links)
Ever since Robert Brustein’s review of The Dark at the Top of the Stairs in November 1958, the role of the female characters in William Inge’s plays has been of interest to a number of critics. At that time, Brustein claimed that Inge’s female characters were "men-taming women" who were castrative to their husbands. After the publication of his review, many critics followed in suit and also described Inge’s women in the same terms; however, only one of these critics, Janet Juhnke, examines the correlation between Inge’s female characters and Betty Friedan’s The Feminine Mystique. Junke takes issue with Brustein’s claims and disagrees with his label of the female characters are predatory, castrative wives. While Juhnke makes some good points, her analysis of Inge’s most well-known plays lacks much depth. Even Come Back, Little Sheba, which she spends the most time discussing, has not been completely explored for its connections to the trends presented in Friedan’s The Feminine Mystique. In fact, a compromise between Brustein’s and Juhnke’s observations may be possible in that Friedan found that women trapped in the feminine mystique often did become castrative wives. Thus, this thesis will take a close examination of the comparisons between William Inge’s female characters and the women Friedan describes in The Feminine Mystique. It argues that these women exhibit symptoms similar to those Friedan describes: boredom, a preoccupation with sex, and unhealthy mother-child relationships. / Thesis (M.A.)--Wichita State University, Dept. of English. / "May 2006." / Includes bibliographic references (leaves 35-36)
|
46 |
Burying aunt Billie and other storiesMcCloughan, Troy Michael 05 1900 (has links)
Being rich -- Germinate -- Inside -- Leaving the herd -- Burying aunt Billie. / Thesis (M.F.A.)--Wichita State University, Dept. of English. / "May 2006."
|
47 |
Cracking the Urn: master and slave in "Ode on a Grecian Urn"Bell, Justin 05 1900 (has links)
In the "Ode on a Grecian Urn", the poet-speaker uses many tools to distance himself from the urn. Many critics have argued for Keat’s agreement with the urn, using the poet’s letters and notions of Romanticism as guide. These criticisms, though, falter once stronger interpretations enter. Pronoun usage--ye and thee-- strongly affect the overall meaning of the work and the last lines in particular. Keats, aware of this pronoun usage as it still exists in poetry but not spoken language at the time of the ode’s creation, uses it for conflict. Keats also employs pastoral tradition to set up conflicts between port-speaker and urn. Keat’s letters also point to a belief in experience over escape. All these approaches demonstrate the binary opposition the ode employs. Each force, the urn and the speaker, employ a conflicting argument. The speaker sees stilled time and mentions change, and the speaker sees the ideal and comments on pain. This multi-faceted conflict, though, travels past a simple disagreement. The master-slave interpretation sheds new light on this conflict and shows how the speaker can destroy the urn. / Thesis (M.A.)--Wichita State University, Dept. of English. / "May 2006."
|
48 |
Singapore airlines: a study in exemplary crisis communicationTan, Ee Ling J. 05 1900 (has links)
On October 31, 2000, Singapore Airlines’ Flight SQ0006 crashed into construction equipment 11 seconds after take off and exploded into three pieces. The flight was bound for Los Angeles from Taipei’s Chiang Kai-Shek Airport. There were 159 passengers and 20 crew members on board the flight. The accidents caused 83 fatalities; there were 56 people injured and 40 people escaped unscathed. As it taxied down a closed runway, the aircraft hit a piece of construction equipment and exploded. This thesis uses qualitative methodology to study Singapore Airline’s handling of this crisis from a rhetorical perspective. The dynamic generic framework by Huxman and Bruce (1995) is used to examine the defense rhetoric that Singapore Airlines used to uncover the interactions between the situational (nature of crisis), substantive (posture of company) and stylistic (argument of company) rhetorical makers. There are three findings from this case study. Firstly, the recovery and learning phase of a crisis can be speeded up if investigations are conducted by a neutral party. Secondly, it is important for companies to have well-trained crisis response teams, such as the Buddy system used by Singapore Airlines, as it provides companies with additional critical resources needed to facilitate crisis management. Thirdly, if the relationship between the accused and the accuser needs to be preserved, the accused will likely be constrained to basing arguments on stasis of jurisdiction. / Thesis (M.A.)--Wichita State University, College of Liberal Arts and Sciences, Elliott School of Communication / Includes bibliographic references (leaves 50-53) / "May 2006."
|
49 |
Evaluating cardiac gene expression in maternal phenylketonuria offspringMcCoy, Jennifer Ellie 05 1900 (has links)
Maternal phenylketonuria (MPKU) is a teratogenic syndrome, caused by development of offspring in a uterine environment made toxic by the metabolic imbalance of PKU. The birth defects resulting from untreated MPKU include microcephaly with concomitant mental retardation, growth retardation, and congenital heart defects. Congenital heart defects have been identified and characterized in MPKU offspring, using the BTBR-PAHenu2 mouse MPKU model. Subsequently, this mouse model was used to start investigating the molecular basis of MPKU congenital heart defects. It was determined that three genes involved in heart contractility and development were significantly downregulated in MPKU fetal hearts at 18.5 days postcoitum, compared to non-PKU control offspring. These three genes were troponin T2 (Tnnt2), troponin I3 (Tnni3), and ryanodine receptor 2 (Ryr2). We used the BTBR-PAHenu2 mouse model to further evaluate the relationship between maternal hyperphenylalaninemia and cardiac gene expression in MPKU fetal hearts. It was hypothesized that an association exists between maternal blood phenylalanine (Phe) levels and expression levels of certain cardiac genes. More specifically, our alternate hypothesis stated that elevated maternal blood Phe levels are associated with decreased expression of Tnnt2, Tnni3, and Ryr2 in MPKU fetal hearts. Relative quantification of Tnnt2, Tnni3, and Ryr2 transcript abundance in MPKU fetal hearts was performed using real-time PCR. Linear regression analysis was then performed on relative Tnnt2, Tnni3, and Ryr2 transcript levels as a function of maternal blood Phe concentration. The regression analyses for all three genes were found to be nonsignificant. Therefore, we were unable to reject the null hypothesis, which stated that there is no association between maternal blood Phe levels and the abundance of Tnnt2, Tnni3, and Ryr2 transcripts in MPKU fetal hearts. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences / Includes bibliographic references (leaves 33-39).
|
50 |
Reassessment of intra- and extra-ovarian expression of growth differentiation factor-9Bowser, Jessica Lynn 05 1900 (has links)
Mammalian ovarian organogenesis is characterized temporally by oogonial mitosis, oogonial apoptosis, rescue of germ cells via interaction with somatic cells to form primordial follicles, and entrance into meiosis. Recent studies suggest that germ cell’s activity participate in this process via the production of local regulatory factors. Growth differentiation factor-9 (GDF-9), a novel transforming growth factor-family member, is expressed in ovaries of various species as a crucial factor in ovarian follicular development. Likewise, the expressional pattern of GDF-9 in nonovarian tissues has remained elusive, as current data continues to support the exclusive expression of GDF-9 within the mammalian ovary. Recently, our lab became interested in the pattern of expression associated with GDF-9 as it pertains to ovarian organogenesis and follicle formation in the neonatal hamster ovary due to the ability to obtain ovaries at specific stages of follicular organization. Further interests include investigating the possible expression of GDF-9 in nonovarian tissues. Consensus oligonucleotide primer pairs spanning at least one intron for GDF-9 were determined by analysis of the gene sequences for human, mouse, rat, bovine, and ovine for use in the hamster. mRNA for GDF-9 in ovarian and non-ovarian tissues was detected by RT/PCR using total RNA. PCR products were sequenced to determine the degree of homology for the gene relative to that of other species (mouse 91%, rat 90%, and human 84%). mRNA for GDF-9 was detected in ovarian samples for all days examined (Days 1, 3, 5, and 6-9 post delivery [Day 0]. This time frame reflects periods of active oogonial mitosis (Days 1 and 3), oogonial atresia (Day 5), and primordial follicle formation (Days 6-9). Translation of GDF-9 was observed prior to primordial follicle development (Day 5). For non-ovarian analysis mRNA, expression of GDF-9 was detected in several tissues (liver, kidney, spleen, and testis) at various stages of growth and development. Furthermore, white blood cells retrieved from adult hamsters revealed mRNA expression of this novel growth factor. Kidney perfusion experiments supported the idea that mRNA expression of GDF-9 in non-ovarian tissues could be the resultant of circulating white blood cells as a 35% reduction was seen in perfused samples. Immunological analyses of hamster ovarian sections detected expression of GDF-9 within the highly vascularized regions of the corpus luteum. In fact, re-investigations of early stage immunological analyses for GDF-9 suggest that mast cells are potential sites of GDF-9 protein expression. Reports suggest that GDF-9 is expressed exclusively in the ovary, specifically within the oocytes, and that expression of GDF-9 is not seen prior to primordial follicle formation. Our results conclude several revolutionary findings pertaining to ovarian and non-ovarian expression of GDF-9. Importantly we report that GDF-9 mRNA is expressed in the ovary prior to and during primordial follicle formation, and after ovarian senescence. And that GDF-9 is non-ovarian specific as previously indicated by scientific literature as we have localized non-ovarian transcription and translation of GDF-9 to white blood cells. Currently, only one type of immunologic cell, mast cells, has been identification to express GDF-9. Further individual white blood cell assays will be required to identify additional specific white blood cell expression of GDF-9. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences / "May 2006."
|
Page generated in 0.1573 seconds