The purpose of this study was to examine the synergistic effects of Bactrachochytrium dendrobatidis (chytrid fungus) and sub-lethal nitrate concentrations on fitness response of the African Clawed Frog, Xenopus laevis. The concern is that the increases in environmentally accelerated anthropogenic influenced nitrogen cycling has stressed otherwise healthy amphibians and, when introduced with B. dendrobatidis, the amphibians are less able to mount an appropriate immune response. The purpose of the experiment to determine if fitness cues normally unseen with infected Xenopus laevis frogs and tadpoles will be exacerbated when influenced with environmentally relevant increased nitrate levels. Conversely, our null hypothesis was no change in fitness when subjected to both B. dendrobatidis and nitrate. The use of this species allowed researchers to test changes that occurred without concern of killing native, naïve species further, thus allowing us to study stressors rather than the outcome of the disease in naïve species (i.e. death). Results indicate tadpoles exposed to high nitrate concentrations experience increased mortality, clutch variability, differences in growth when exposed to chytrid, and increased weight at metamorphosis was uncoupled from time to metamorphosis. Post-metamorphic observations indicate clutch variability, body weight affected by nitrate, and chytrid infection after metamorphosis. Chytrid infection before metamorphosis had no impact on growth or development in post-metamorphic results. Body condition was also significant among nitrate groups and clutches. Regression analyses indicate those exposed to the highest nitrate concentrations experienced a greater increase in weight after metamorphosis experiencing a response reaction similar to other treatment groups. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences.

Researching cryptic biodiversity is an integrative process that uses a “total evidence” approach to identify population-level evolutionary lineages (species). Cryptic species of aroids have been discovered but the existence of cryptic pollinator species has not been addressed. The highly polymorphic scarab beetle, Cyclocephala sexpunctata, is a hypothesized pollinator of two cryptic aroid species. This research integrates detailed morphological data, spatial and distribution data, mitochondrial CO1 sequence data and host plant associations to test the hypothesis that cryptic species of Cyclocephala are visiting aroid flowers. Nine morphologically similar Cyclocephala species were included to address identification problems among similar species. A new country record was found for C. pan (Honduras). A female paratype specimen of C. letiranti was determined to be a female C. sexpunctata raising the possibility that there are no female type specimens of C. letiranti. Four unique male paramere forms (morphotypes) were found in C. sexpunctata and the allied species C. brevis. These paramere forms were associated with four female morphotypes that have a diagnostic form of the ventral surface of the epipleural pillow. The ventral form of the female epipleural pillow is described here for the first time and is a new character for the genus Cyclocephala. Detailed elevational and distribution data indicate that the morphotypes of C. sexpunctata and C. brevis are rarely collected together at specific localities. A checklist of cyclocephaline floral associations was compiled. Examination of voucher specimens and published floral associations indicate that the morphotypes described here visit different species of flowers within their hypothesized elevational range. Mitochondrial CO1 data demonstrate that C. sexpunctata is polyphyletic but the monophyly of C. brevis could not be addressed. The combination of these datasets indicates that the morphotypes described here are cryptic species though their taxonomy remains unresolved due to large numbers of synonyms. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences.

A multi-entry experimental study was conducted to investigate the effects of roughness, simulated ice shapes, and various combinations of roughness and simulated shapes on aerodynamic performance of a reflection plane wing model. All testing was conducted at the Wichita State University 7 ft by 10 ft wind tunnel facility. Roughnesses tested included 12, 16, 20, 24, 40, 80 and 100 grit sandpaper in coverages including 5%c on the lower surface to 5%c on the upper surface, 10%c on the lower surface to 10%c on the upper surface, and 20%c on the lower surface to 20%c on the upper surface. Simulated ice shapes tested included 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, and 12.7 mm quarter round step ice shapes along with a 1 mm round ice shape. Locations for step ice placement included 1%c, 3%c, 5%c, 8%c, 10%c, 12%c, 15%c, 20%c, 25%c, and 36%c on the upper surface in addition to 1%c, 5%c, 10%c, and 15%c on the lower surface. Combinations of step ice and roughness to simulate observed ice shapes from an icing tunnel test and an aluminum leading edge ice shape to simulate a long growth ice accretion were also investigated. The various components of the simulated configurations were varied do ascertain which features drove performance degradation. Results indicated that most configurations decreased the slope of the lift curve. CLstall was reduced by as much as 46.5% with respect to the clean wing when the SI12-15-US configuration was installed on the wing. At the other end of the range of changes to CLstall, the SI4-15-US configuration caused an increase of 12%. The leading edge ice shape caused the largest movement in aerodynamic center of any configuration tested. The largest increase in minimum drag was seen with the LEice-R10 configuration at an increase of nearly 110%. All ice shapes exhibited a positive slope for the CM curve with the leading edge ice shape having the highest observed slope. Control surface deflections had a relatively uniform impact on all aerodynamic forces impact regardless of the installed ice shape. Installations of simulated ice shapes on the lower surface primarily impacted drag performance with minimal degradation to lift performance. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering.

This thesis presents a dynamically feasible and real-time trajectory path generation algorithm for unmanned aerial vehicles (UAVs) flying through a sequence of a random N number of waypoints (WPs) in three dimensions. Pontryagin’s minimum principle was used to show that the straight-line path segments connecting the sequence of waypoints are time optimal [1]. An algorithm was designed so that the total trajectory path length of a UAV is approximately equal to the straight-line path of the waypoints. The trajectory path obtained was also compared with the one-circle method, and it was found that the proposed method has less path length. Issues related to this algorithm are explained in detail. Simulation results show the efficiency of the method. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

This thesis investigates the effects of biologically inspired leading-edge protuberances on aircraft wings. The study of humpback whales and their flipper performance was the impetus to modifying the leading edge of an aircraft wing in order to gain an aerodynamic advantage during flight. This study examines the effect of leading-edge modification on wing performance at a low Reynolds number (Re), since low Reynolds number flows have unique features, and the knowledge about this flight regime is extremely important for small aircraft, called unmanned aerial vehicles (UAVs), flying at low speeds. Simulations were executed on wings with leading-edge sinusoidal protuberances, in order to compare the lift and drag characteristics with that of a wing with a smooth leading edge. All wings had the same cross section of National Advisory Committee for Aeronautics (NACA) 2412 and a simulated Reynolds number of 5.7 * 10^5. Results from numerical simulations revealed that a decrease in lift and an increase in drag was observed at low angles of attack (AoA) in all cases of the modified wings. At higher angles (α ≥16º), the lift of the modified wings was up to 48% greater than the baseline wing, with 44% less drag or no drag penalty. The amplitude of protuberances significantly affects wing performance. Although the maximum lift generated by modified wings was lower than baseline, protuberances along the leading edge of the wing proved to have a profound advantage in obtaining higher lift at high angles of attack. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering.

The statistical disclosure attack (SDA) is quite an effective method for attackers to go against an anonymity system and to reveal the information behind it. It targets at a particular anonymity system user, tries to find its sending/receiving relationship with others after a long term observation. In this thesis, we first make an improvement for SDA, using weighted mean instead of the orginal arithmetic mean to calculate the cumulative observed receiver popularity in order to get a more precise value of the attack result. Second, we present an analysis for the effectiveness of the sender generated cover traffic, showing that employing this kind of cover traffic helps little on protecting anonymity system users against a sophisticated attacker. The analysis also validates an earlier empirical result of the ineffectiveness of sender generated cover traffic. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

In this thesis we present a critical analysis of the system-wide anonymity metric by Edman et al. [1], which is based on the permanent value of a doubly-stochastic matrix. From the view of intuitive understanding, we show that a metric that looks no further than the permanent, a composite value, is at best a rough indicator of anonymity, We find the range where its inaccuracy is acute, and propose a better anonymity indicator. Also, we show that this metric fails to possess desirable generalization properties by constructing an information-preserving embedding of a smaller class of attacks into the wider class for which this metric was proposed. Finally, we show a new general, accurate anonymity metric that does not exhibit these shortcomings. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science.

An ad hoc network consists of wireless nodes that communicate through cooperation with each other, and operate independently of additional network devices such as routers and switches. These networks are self-sufficient and distributed in nature which are most widely used in the areas where there is little or no infrastructure available, like battlefields, weather forecast applications, etc. Recently ad hoc networks have been deployed in many places and have become a part of everyone’s life. Devices such as laptops, smartphones, and netbooks are using it as one option for wireless networks. This emerging trend poses a serious security issue. As there is no centralized authority, establishing trust between devices in an ad hoc network is very important. Trust management among the nodes in an ad hoc network, or between the nodes of different networks, is a must and needs to be managed without compromising node functionality. In this thesis, a new trust method is proposed which manages directly and indirectly connected nodes, and is also able to resolve issues concerning the unfair trust value grading between neighbors and the destination node. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

We present a graphical framework containing certain in nite pro les of probability distributions that result from an attack on an anonymity system. We represent currently popular anonymity metrics within our framework to show that existing metrics base their decisions on just some small piece of information contained in a distribution. This explains the counterintuitive, thus unsatisfactory, anonymity evaluation performed by any of these metrics for carefully constructed examples in literature. We then propose a new anonymity metric that takes entire pro les into consideration in arriving at the degree of anonymity associated with a probability distribution. The comprehensive approach of our metric results in correct measurement. A detailed comparison of our new metric, especially with the popular metrics based on Shannon entropy, gives the rationale and degree of disagreement between these approaches. vi / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

This thesis describes the work on understanding the phase behavior of mixed surfactant systems and on the surface-functionalization and modification of catanionic vesicles with an aim toward probing protein-carbohydrate multivalent interactions. To understand the phase behavior of aqueous mixture of cetyltrimethylammonium tosylate (CTAT) and sodium dodecylbenzenesulfonate (SDBS) solutions at micromolar surfactant concentrations, calculations were performed in conjunction with fluorescence correlation spectroscopy (FCS) studies to probe the composition and size of aggregates formed at low concentration. Toward this end, the critical micelle concentration (cmc) of CTAT was measured to be 0.12-0.35 mM and cmc of SDBS to be 2.2-2.8 mM, both values agree with literature values. The critical aggregation concentration (cac) for the mixtures of CTAT and SDBS having a 1.8-fold molar excess of CTAT was measured to be 2.6 μM. Using these measured values, for CTAT-rich mixtures, the mole fraction of CTA+ in the vesicle bilayer is calculated to be 0.56 at the cac. The interaction parameter is calculated to be -24. These calculations in this thesis suggest that the surface charge at low surfactant concentration near the cac. This theoretical prediction was supported by FCS studies of DNA and CTAT-rich vesicles binding near the cac. Next the catanionic vesicle outer membrane was functionalized by hydrophobic insertion of hydrocarbon chain of the glycoconjugate n-dodecyl-β-D-glucopyranoside (C12-Glu). Kinetics of multivalent interactions between the lectin concanavalin A and C12-Glu was studied by cryo-TEM and stopped-flow turbidometry. Inhibition multivalent binding studies were conducted and a potential new tool has been developed in evaluating multivalent inhibition. / Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry