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Multidisciplinary interactions are expected to play a significant role in the design of future high-performance aircraft (Blended-Wing Body, Truss-Braced wing, High Speed Civil transport, High-Altitude Long Endurance aircraft and future military aircraft). Also, the availability of supercomputers has made it now possible to employ high-fidelity models (Computational Fluid Dynamics for fluids and detailed finite element models for structures) at the preliminary design stage. A necessary step at that stage is to calculate the wing angle-of-attack at which the wing will generate the desired lift for the specific flight maneuver. Determination of this angle, a simple affair when the wing is rigid and the flow regime linear, becomes difficult when the wing is flexible and the flow regime non-linear. To solve this inherently nonlinear problem, a Newton's method type algorithm is developed to simultaneously calculate the deflection and the angle of attack. The present algorithm requires the sensitivity of the aerodynamic pressure with respect to each of the generalized displacement coordinates needed to represent the structural displacement. This sensitivity data is easy to determine analytically when the flow regime is linear. The present algorithm uses a finite difference method to obtain these sensitivities and thus requires only the pressure data and the surface geometry from the aerodynamic model. This makes it ideally suited for nonlinear aerodynamics for which it is difficult to obtain the sensitivity analytically. The present algorithm requires the CFD code to be run for each of the generalized coordinates. Therefore, to reduce the number of generalized coordinates considerably, we employ the modal superposition approach to represent the structural displacements. Results available for the Aeroelastic Research Wing (ARW) are used to evaluate the performance of the modal superposition approach. Calculations are made at a fixed angle of attack and the results are compared to both the experimental results obtained at NASA Langley Research Center, and computational results obtained by the researchers at NASA Ames Research Center. Two CFD codes are used to demonstrate the modular nature of this research. Similarly, two separate Finite Element codes are used to generate the structural data, demonstrating that the algorithm is not dependent on using specific codes. The developed algorithm is tested for a wing, used for in-house aeroelasticity research at Boeing (previously McDonnell Douglas) Long Beach. The trim angle of attack is calculated for a range of desired lift values. In addition to the Newton's method algorithm, a non derivative method (NDM) based on fixed point iteration, typical of fixed angle of attack calculations in aeroelasticity, is employed. The NDM, which has been extended to be able to calculate trim angle of attack, is used for one of the cases. The Newton's method calculation converges in fewer iterations, but requires more CPU time than the NDM method. The NDM, however, results in a slightly different value of the trim angle of attack. It should be noted that NDM will converge in a larger number of iterations as the dynamic pressure increases. For one value of the desired lift, both viscous and inviscid results were generated. The use of the inviscid flow model while not resulting in a markedly different value for the trim angle of attack, does result in a noticeable difference both in the wing deflection and the span loading when compared to the viscous results. A crude (coarse-grain) parallel methodology was used in some of the calculations in this research. Although the codes were not parallelized, the use of modal superposition made it possible to compute the sensitivity terms on different processors of an IBM SP/2. This resulted in a decrease in wall clock time for these calculations. However, even with the parallel methodology, the CPU times involved may be prohibitive (approximately 5 days per Newton iteration) to any practical application of this method for wing analysis and design. Future work must concentrate on reducing these CPU times. Two possibilities: (i) The use of alternative basis vectors to further reduce the number of basis vectors used to represent the structural displacement, and (ii) The use of more efficient methods for obtaining the flow field sensitivities. The former will reduce the number of CFD analyses required the latter the CPU time per CFD analysis. NOTE: (03/2007) An updated copy of this ETD was added after there were patron reports of problems with the file. / Ph. D.

[pt] A vida pode ter se originado na Terra a partir de moléculas prebióticas que chegaram transportadas por corpos extraterrestres. A análise de fragmentos do meteorito Murchison sugere que sua composição é constituída de material produzido antes do início da vida terrestre atual. Em seu interior foram encontrados 17 aminoácidos primários e 13 açúcares. Sabendo que os aminoácidos, blocos constituintes de proteínas, são fundamentais na composição de todos os organismos vivos, a comunidade acadêmica propôs uma teoria da evolução com princípios exógenos. Considerando que partículas α com energia em torno de 1 keV são muito abundantes no Sistema Solar, este trabalho tem como objetivo determinar experimentalmente a radiorresistência da glicina. Assim, são estudados os diferentes efeitos da radiação devido a essa interação, como sputtering e radiólise. Os experimentos foram realizados no Laboratório Van de Graaff da PUC-Rio, onde filmes de glicina foram preparados e irradiados por um feixe de íons de He+ com energias de 0,5, 1,0, 1,5 e 2,0 keV produzidos por um pequeno canhão de íons. A espectroscopia por infravermelho (FTIR) foi utilizada para analisar os efeitos da irradiação. Dados experimentais mostram que a seção de choque de destruição (𝜎𝑑) da glicina depende da energia do feixe e da temperatura da amostra. As seções de choque em função da temperatura foram determinadas e variam entre 10-18 e 10-15 cm2: temperaturas mais baixas resultam em menores 𝜎𝑑. Em função da energia, 𝜎𝑑 varia entre 10-16 e 10-1 cm2, sendo seus maiores valores correspondentes às maiores faixas de energia. Além disso, esta pesquisa procurou descobrir se moléculas-filhas surgem após a irradiação de glicina com partículas α de keV. Ademais, para modelar os resultados experimentais, foi desenvolvido um software denominado TRIM-estendido. / [en] Life may have originated on Earth from prebiotic molecules that arrived brought by extraterrestrial bodies. Fragments analysis of Murchison meteorite suggests that it is made of Solar System (SS) primitive material before the beginning of nowadays terrestrial life. In its interior, 17 primary amino acids and 13 sugars were found. Knowing that amino acids, building blocks of proteins, are fundamental in the composition of all organisms, the academic community suggests the possibility of an evolution theory based on exogen principles. A major question is how the prebiotic material could survive billions of years in the interplanetary medium. Considering that α particles with energy of about 1 keV are very abundant in the SS, this work aims to determine experimentally the glycine radioresistance. Thus, the different radiation effects due to this interaction, like sputtering and radiolysis, is studied. Experiments were performed at the Van de Graaff Laboratory of PUC-Rio, using a He+ beam produced by a keV accelerator. Glycine films were prepared and irradiated by the He+ beam ions with energies of 0.5, 1.0, 1.5 and 2.0 keV. Infrared spectroscopy (FTIR) was used to analyze the irradiation effects. Experimental data show that Glycine destruction cross section depends on the beam energy and on sample temperature. The energy dependence indicates that at low energies, glycine absorbance decay faster than at higher energies. Additionally, this research intends to find out if daughter molecules arise after Glycine irradiation with α keV particles. The TRIM-extended model was developed for modelling the experimental data.

<p>This objective of this study was to determine the impact of antimicrobial carcass washes on beef trim quality in the production of frankfurters. Twenty-four beef carcasses were randomly applied a different antimicrobial wash treatments (TRT) during the harvest procedure: 82° C water (CON), peroxyacetic acid (PAA), or lactic acid (LA). Beef carcasses were analyzed for microbial counts and carcass pH. Frankfurters were produced using carcass trim at two different batter temperature processes (PROC): 4°C (CP) or 21°C (HP). Frankfurters were analyzed for cook loss, emulsion stability (ES), color (Minolta L*, a*, b*) over 60-day storage, purge loss, texture, and sensory analysis. LA carcass had a lower pH (6.36; <i>P</i><0.001) 30 min post wash compared to other wash treatments. Frankfurters produced from CON trim had the highest ES water (<i>P</i><0.0001) and ES fat (<i>P</i><0.0001) separation where the LA and PAA treatments were not significantly different (<i>P</i>>0.05). The HP frankfurters had less ES water (<i>P</i><0.0001) and ES fat separation (<i>P</i><0.0001) when compared to CP. However, the CP had a higher cook yield (<i>P</i>=0.002). The HP frankfurters had higher internal and external L* values (<i>P</i><.0001; <i>P</i><.0001, respectively). The CP frankfurters had a higher a* (redness) internal color values (<i>P</i><.0001). However, the HP frankfurters had a higher external a* value (<i>P</i><.0001). The HP frankfurters displayed higher internal and external b* (yellowness) values (<i>P</i><.0001). Sensory results displayed the CP frankfurter to have an increase in hardness (<i>P</i>=0.004), a decrease in cohesiveness (<i>P</i>=0.03) and an increase in juiciness (<i>P</i><.0001). Texture analysis hardness (<i>P</i>=0.009) and chewiness (<i>P</i>=0.01) results showed the CON frankfurters were significantly harder than PAA (<i>P</i><0.05), while LA were not different from CON or PAA frankfurters (<i>P</i>>0.05). The CP frankfurters were found to have a decrease in springiness (<i>P</i>=<.001) and cohesiveness (<i>P</i>=0.03). There was a significant difference in microbial reduction of pre to post wash petri film counts for all treatments (Log₁₀CFU/mL) of aerobic plate count (<i>P</i>= <0.0001), E.<i>coli</i> coliform (<i>P</i>= 0.0002), yeast (<i>P</i>=0.04) and mold (<i>P</i>= <0.001). TRT was found to be significant for APC (<i>P</i>=0.06) and yeast (<i>P</i>=0.004). Overall, our research indicated antimicrobial wash treatments have little effect on frankfurter quality and displayed viable methods for reducing microbial growth on beef carcasses. </p> <br>

The need of a stable production of At-211 is necessary to continue research in alpha-particle targeted radionuclide therapy. Our objectives were to establish the production of Astatine-211 at Texas A&M Cyclotron Institute, optimize the production methods to reduce the generation of contaminants and maximize At-211 production, and assess the radiological safety aspects of At-211 production. The production of the alpha-particle emitting radionuclide At-211 was performed at the Texas A&M Cyclotron Institute using the K500 superconducting cyclotron following the production reaction Bi-209(α, 2n)At-211 using a thick bismuth target of 500 μm. We carried out two irradiation experiments where the initial energy of the alpha-particle beam, 80 MeV, was degraded using multiple copper and aluminum foils to 27.8 and 25.3 MeV, respectively. The end of beam time was 4 hours for both experiments. The resulting At-211 yields were 36.0 and 12.4 MBq/μA-h, respectively. Several impurities were produced using the 27.8 MeV, which included At-210 and Po-210. However, when the 25.3 MeV beam was used, the impurities At-210 and Po-210 were resolved and other contaminants were minimized to less than 0.8% of At-211 yield. The production yields were in accordance to previous published results. From the success of these initial experiments, additional steps were taken to produce At-211 in excess quantities for distillation purposes. In order to obtain viable quantities of At-211, the gross yield needed to be increased due to losses that are incurred during distillation and radioactive decay. The ability to produce high yields of this isotope required a redesign of the target and use of the K150 cyclotron using a higher beam intensity.

In this thesis the development of a nonlinear simulation model of a utility helicopter and the design of its automatic flight control system is addressed. In the first part of this thesis, the nonlinear dynamic model for a full size helicopter is developed using the MATLAB/SIMULINK environment. The main rotor (composed of inflow and flapping dynamics parts), tail rotor, fuselage, vertical stabilizer, horizontal stabilizer of the helicopter are modeled in order to obtain the total forces and moments needed for the flight simulation of the helicopter. Total forces and moments are used in 6 degrees of freedom equations of motion model and helicopter states are calculated for the specified flight conditions such as hover and forward flight. Trim and linearization programs are developed. The linearized models of hover and forward flight conditions are used for the automatic flight control system design. Automatic flight control system model consists of necessary systems in order to ease the pilot control of the helicopter. A classical inner stability loop and outer flight directory mode approach is taken to design the automatic flight control system. For the inner stability loop both classical rate feedback and truncated system state feedback control approaches are used. The outer loop modes implemented are heading hold, attitude hold (pitch, roll), altitude acquire and hold mode for hover condition and heading hold, attitude hold (pitch, roll), altitude acquire and hold mode and airspeed hold for forward flight condition. Finally, the success of the controllers are demonstrated through nonlinear simulations for different flight directory modes in hover and forward flight conditions.

Publication bias is one threat to validity that researchers conducting meta-analysis studies confront. Two primary goals of this research were to examine the degree to which publication bias impacts the results of a random effects meta-analysis and to investigate the performance of five statistical methods for detecting publication bias in random effects meta-analysis. Specifically, the difference between the population effect size and the estimated meta-analysis effect size, as well as the difference between the population effect size variance and the meta-analysis effect size variance, provided an indication of the impact of publication bias. In addition, the performance of five statistical methods for detecting publication bias (Begg Rank Correlation with sample size, Begg Rank Correlation with variance, Egger Regression, Funnel Plot Regression, and Trim and Fill) were estimated with Type I error rates and statistical power. The overall findings indicate that publication bias notably impacts the meta-analysis effect size and variance estimates. Poor FTSe I error control was exhibited in many conditions by most of the statistical methods. Even when Type I error rates were adequate the power was small, even with larger samples and greater numbers of studies in the meta-analysis.

The thesis presents data from butterfly transects monitoring, carried out for 7 years on 36 transects established both within nature reserves and unprotected landscapes throughout the Czech Republic and walked three times a month between April and September. Only seven transects were monitored for the whole monitoring period. There were 192 771 individual butterfly records on 127 species of butterflies and burnet moths, i.e. 76.5% of the Czech fauna of the targeted groups). Data on their abundances are for the first time available for the Czech Republic. The distribution of individual species abundances approximated a lognormal model. The abundant species were generalists of non-wooded habitats, which prosper in the intensively managed landscapes of the Czech Republic. Trends of abundance, determined by the TRIM program, were estimable for 92 species. Over the monitored period, the relative abundance of nine species significantly decreased, while those of of seven species significantly increases. The remaining 76 did not display unequivocal trends, but still, 17 are likely increasing and 29 likely decreasing. Comparing the trends with the life history and bioclimatic traits of the butterflies showed that species whose abundance did not change possess traits typical for generalist butterflies (mobile species, overwintering in later life stages, longer flight period etc.), while decreases were more common among thermophilic species. Splitting the analyses for data originating from reserve vs. unprotected areas suggested that mesophilic species and species of more advanced successional stages prosper outside of reserves, whereas thermophilic species tend to decline there, and that an opposite pattern applies to reserves. I discuss recommendations for future of the monitoring Czech butterfly monitoring scheme.

The ongoing fast pace research in hardware and software technology has resulted in memory devices efficient and faster than ever before. However, the issue of security of the contained data is rarely discussed. There is an evident capability of these devices to retain data even when it is erased. In this thesis, a study is conducted to qualitatively analyze the extent to which data deletion is important and why secure deletion should be applied. Afterwards, following the sequential exploratory procedure, this paper presents an analysis of methods used to recover the data after being deleted in addition to the techniques used to securely delete this data. Based on this study, some recommendations are made to ensure the safety of data.

The Stability And Control CONfiguration (SACCON) model represents an emerging trend in airplane design where the classical tube, wing and empennage are replaced by a single tailless configuration. The challenge is to assure that these designs are stable and controllable. Nonlinear aerodynamic behavior is observed on the SACCON at higher incidence angles due to leading edge vortex structures. Active Flow Control (AFC) used in preliminary design represents a promising solution to the longitudinal stability problems and this was demonstrated experimentally on a semi span model. AFC can be used to trim the SACCON in pitch and it alters forces and moments comparable to common control surface deflections. A combination of AFC and control surface deflection may increase the overall efficiency and opens up a variety of maneuvering possibilities. This implies that AFC should be treated concomitantly with other design parameters and should be considered in the preliminary design process already and not as an add-on tool. Integral force and moment data was supplemented by observations using Pressure Sensitive Paint (PSP) and flow visualization. Two arrays of individually controlled sweeping jets, one located along the leading edge and the other along the flap hinge provided the AFC input needed to alter the flow. The array positioned over the flap-hinge of the model was most effective in stabilizing the wing by decreasing the pitching moment at lower and intermediate angles of incidence. This effect was achieved by reducing the spanwise flow on the swept back portion of the wing through jet-entrainment that also affected the leading edge vortex. Leading edge actuation showed some beneficial effects by inhibiting the formation of the leading edge vortex near the wing tip. A preliminary study using suction was carried out. The tests were carried out at Mach numbers smaller than 0.2 and Reynolds numbers based on the root chord of the model that approached 10⁶.