Low aspect ratio, highly-swept cranked arrow wing planforms are often proposed for high-speed civil transports. These wing planforms offer low supersonic drag without suffering greatly from low lift/drag ratios in low-speed flight. They can, however, suffer from pitch-up at modest angles of attack (as low as 5°) during low-speed flight due to leading edge vortex influence, flow separation and vortex breakdown. The work presented here describes an investigation conducted to study past research on the longitudinal aerodynamic characteristics of highly-swept cranked wing planforms, the development of a new method to estimate pitch-up of these configurations, and the applications of this new method to the analysis of tail designs for trim at high lift coefficients. The survey of past research placed emphasis on 1) understanding the problem of pitch-up, 2) ascertaining the effects of leading and trailing edge flaps, and 3) determining the benefits and shortfalls of tail, tailless, and canard configurations. The estimation method used a vortex lattice method to calculate the inviscid flow solution. Then, the results were adjusted to account for flow separation on the outboard wing section by imposing a limit on the equivalent 2-D sectional lift coefficient. The new method offered a means of making low cost estimates of the nonlinear pitching moment characteristics of slender, cranked arrow wing configurations with increased accuracy compared to conventional linear methods. Numerous comparisons with data are included. The new method was applied to analyze the trim requirement of slender wing designs generated by an aircraft configuration optimization and design program. The effects of trailing edge flaps and horizontal tail on the trimmed lift coefficient was demonstrated. Finally, recommendations were made to the application of this new method to multidisciplinary design optimization methods. / Master of Science

In summary the tilting mechanism helps to explain the overall flow structure and the stability of the leading edge vortex.; The leading edge vortex has been identified as the most critical flow structure for producing lift in flapping wing flight. Its stability depends on the transport of the entrained vorticity into the wake via spanwise flow. This study proposes a hypothesis for the generation and enhancement of spanwise flow based on the chordwise vorticity that results from the tilting of the leading edge vortex and trailing edge vortex. We investigate this phenomenon using dynamically scaled robotic model wings. Two different wing shapes, one rectangular and one based on Drosophila melanogaster (fruit fly), are submerged in a tank of mineral oil and driven in a flapping motion. Two separate kinematics, one of constant angular velocity and one of sinusoidal angular velocity are implemented. In order to visualize the flow structure, a novel three dimensional particle image velocimetry system is utilized. From the three dimensional information obtained the chordwise vorticity resulting from the vortex tilting is shown using isosurfaces and planar slices in the wake of the wing. It is observed that the largest spanwise flow is located in the area between the chordwise vorticity of the leading edge vortex and the chordwise vorticity of the trailing edge vortex, supporting the hypothesis that the vortex tilting enhances the spanwise flow. Additionally the LEV on the rectangular wing is found to detach at about 80% span as opposed to 60% span for the elliptical wing. Also, two distinct regions of spanwise flow, one at the base and one at the tip, are observed at the beginning of the sinusoidal kinematic, and as the velocity of the wing increases these two regions unionize into one. Lastly, the general distribution of vorticity around each wing is found to be nearly the same, indicating that different wing shapes do not greatly affect the distribution of vorticity nor stability mechanisms in flapping flight.

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The purpose of this qualitative study was to examine middle and high school principal roles prior to and during the COVID-19 pandemic to gain a better understanding about how leadership responsibilities adapted or changed. Data collection strategies included one-on-one interviews with nine middle and high school principals in East Tennessee. To qualify for the study participants had to have experience in the principalship prior to the pandemic. The analysis of data was based on the theoretical frameworks of adaptive leadership (Heifetz et al., 2009) and change theory (Fullan, 2020). The results revealed five key themes that were consistent during the interviews both prior to and during the pandemic: (a) instructional leadership, (b) school culture and climate, (c) school management, (d) community partnerships, and (e) relationships. The following four emergent themes were specific to adaptive changes principals identified while leading during the pandemic: (a) social-emotional awareness, (b) digital teaching and learning, (c) communication, and (d) whole child.

Entrainment is the rhythmic coordination of movement with a signal or other person. Most studies on entrainment have looked at synchronization with auditory or visual signals, whereas much less is known about how entrainment emerges mutually between individuals, especially when they are in physical contact with one another. In this dissertation, I empirically explored dance partnering as an ecological model for understanding interpersonal entrainment through haptic interaction. I began by performing a statistical meta-analysis of functional neuroimaging articles devoted to the most common experimental paradigm for entrainment, namely externally-paced finger tapping to an acoustic rhythmic stimulus (Chapter 2). The results showed that the cerebellar vermis was a strong neural marker of entrainment, as it was more activated by externally-paced tapping than by self-paced tapping, whereas the basal ganglia was activated by both types of rhythmic movements. Next, I used functional magnetic resonance imaging (fMRI) with a group of participants trained at couple dancing in order to explore the neural basis of haptic mutual entrainment, with a focus on the dynamics of leading and following (Chapter 3). While mutual interaction overall engaged brain networks involved in somatosensation, internal-body sensation and social cognition, leading showed enhanced activity principally in areas for motor control and self-initiated action, whereas following showed enhanced activity mainly in sensory and social-cognition areas. Finally, I used 3D motion capture to explore multisensory coupling for mutual entrainment at the group level during folk dancing (Chapter 4). The results showed that dancers relied most extensively on haptic coupling to synchronize as a group, whereas auditory and visual coupling were dependent on the spatiotemporal context. These studies advance our understanding of the neural and behavioural mechanisms underlying joint actions in which entrainment emerges mutually through haptic interaction. / Thesis / Doctor of Philosophy (PhD) / Entrainment is the rhythmic coordination of movement with a signal or other person. Most studies on entrainment have looked at synchronization with auditory or visual signals, whereas much less is known about how entrainment emerges mutually between individuals, especially when they are in physical contact with one another. I began my research by performing a statistical analysis of the literature examining the brain basis of synchronization with auditory signals, identifying a key brain area for entrainment. Next, using a group of participants trained at couple dancing, I explored the brain areas engaged when two individuals in physical contact improvised movement together, focusing on who is leading or following the interaction. Finally, I explored how folk dancers use multiple sensory signals (auditory, visual and tactile) to synchronize as a group. These studies advance our understanding of the neural and behavioural mechanisms by which people mutually entrain through physical interaction.

The purpose of this paper is to identify the obstacles to implement WCOM at beginning in new mills and exploit PDSA loop to cooperate continuous improvements of WCOM. In qualitative way such as semi-structured interviews to revel the existing recognized challenges based on the reflection of middle managers perspective. Noori and Radford’s world class management model, Kotter’s 8 stages process model and Martensen & Dahlgaard’s PDSA model have been applied as three dominating theories. According to interview results, it emphasizes that raising commitment, involvement, consistency and adaptability would accelerate the implementation of BKOM in new mills. However, since the results are limited in the scope of study and cannot be generalize to other industry but worth to investigate and validate in the further study.

The Suite for Violin and Piano, Op. 6 is one of the least-known compositions by Benjamin Britten. It has been considered unfavorably by critics and scholars due to its puzzling mixture of tonal and post-tonal elements. However, this dissertation argues that the suite is composed with a clear tonal framework, and its unique mixed tonal-post-tonal language justifies an in-depth analysis. This analytical study utilizes a linear progression technique - the voice leading produced by passing tones and neighbor notes around focal pitches - to identify tonal areas of the suite.

Using a general, unsteady, nonlinear vortex lattice method, the aerodynamic loads have been found on a 75° delta wing with and without leading edge vortex flaps. The flap had an area approximately 26 percent of the wing area with a constant chord of 6.7 percent of the wing mean aerodynamic chord and was deflected at 30°. Results for lift, drag, axial force, and pitching moment coefficients are compared with experimental data and show very good agreement. Individual pressure difference coefficients along the wing and flap are also presented and compared with experimental data. Overall, the method shows the leading edge vortex flap to be very effective in reducing drag while maintaining lift comparable to that of the plain wing. / Master of Science

There has been recent incentive for understanding the possible deleterious effects that manufacturing deviations can have on compressor blade performance. This is of particular importance in today's age, as compressor designs are pushing operating limits by employing fewer stages with higher loadings and are designed to operate at ever higher altitudes. Deviations in these advanced, as well as legacy designs, could negatively affect the performance and operation of a core compressor; thus, a numerical investigation to quantify manufacturing deviations and their effects is undertaken. Data from three radial sections of every compressor blade in a single row of a production compressor is used as the basis for this investigation. Deviations from the compressor blade design intent to the as-manufactured blades are quantified with a statistical method known as principle component analysis (PCA). MISES, an Euler solver coupled with integral boundary-layer calculations, is used to analyze the effects that the aforementioned deviations have on compressor blade performance when the inlet flow conditions produce a Mach number of approximately 0.7 and a Reynolds number of approximately 6.5e5. It was found that the majority of manufacturing deviations were within a range of plus or minus 4 percent of the design intent, and deviations at the leading edge had a critical effect on performance. Of particular interest is the fact that deviations at the leading edge not only degraded performance but significantly changed the boundary-layer behavior from that of the design case. / Master of Science