X-HALE: the Development of a Research Platform for the Validation of Nonlinear Aeroelastic Codes

In conjunction with the Air Force Institute of Technology (AFIT) and the Air Force Research Laboratory (AFRL), the University of Michigan has designed and is currently building a remotely piloted aircraft (RPA) experimental high altitude long endurance (X-HALE) aircraft to collect non-linear aeroelastic data to validate HALE aircraft design codes developed by academia, industry, and the federal government. While X-HALE is representative of HALE aircraft, the manufacturing and evaluation techniques are applicable to larger full size HALE aircraft such as the concepts being developed under Defense Advanced Research Projects Agency\u27s (DARPA\u27s) Vulture program. This paper documents the development of the X-HALE model to date including a history of the programmatic decisions, basic model configuration, geometric considerations, sensor and system architecture, and manufacturing challenges. Lessons learned from the prototyping include the evolutionary growth of X-HALE\u27s joiner blocks and the manufacturing process of the composite wings. Furthermore, late in the design process, a series of aeroelastic simulations using the Nonlinear Aeroelastic Simulation Toolbox (NAST) developed at the University of Michigan demonstrated the need for a rotating vertical/horizontal stabilizer to aid in the recovery of the vehicle from unstable nonlinear coupled lateral dynamic dutch roll like motion. The documentation and development of X-HALE is critical to the programmatic goal of providing a complete nonlinear aeroelastic data set for the validation of nonlinear aeroelastic analytical tools for government, industry and academia

Simulations for the Test Flight of an Experimental HALE Aircraft

Recent events, such as the crash of NASA\u27s Helios aircraft during a test flight, show that more must be known about the nonlinear control of HALE aircraft. Shearer, Cesnik and their co-workers have developed a code that is a practical solution to the coupled nonlinear aeroelasticity and flight dynamics of very flexible aircraft called the University of Michigan\u27s Nonlinear Aeroelastic Simulation Toolbox (UM/NAST). They are also in the process of developing a model HALE aircraft called X-HALE which will be used to validate this code experimentally. This research performs flight simulations with UM/NAST so as to make predictions about X-HALE\u27s future test flights and subsequently uncover the strengths and weaknesses of UM/NAST when X-HALE is finally flown. These simulations include simulations of straight and level flight and rolling flight. Rolling simulations involve periodic changes in the angle of the ailerons. Both the 6 meter and the 8 meter models of X-HALE are studied. Two control models are compared. These include the linear and non-linear models of UM/NAST

Assessment of egg quality and hatch results of two show hen breeds raised for fancy

Eggs were evaluated in three periods of egg production. Hatching was carried out with the use of eggs from the production peak. The qualities of eggs changed according to the period of production. The largest differences were observed for the thickness of shells, percentage share of the yolk and albumen in an egg and the yolk colour as well as its height and index

Observation of second-harmonic generation in an oriented glassy nematic phase of a closo-decaborane derivative

The optical second-harmonic generation(SHG) and the linear optical properties were investigated in a planar cell containing aligned nonchiral nematic derivative of B₁₀H₁₀²⁻: 1-(4-heptyloxypyridin-1-yl)-10-(4-pentyl-1-thiacyclohexyl)-closo-decaborane (HPTD) as a function of temperature. The compound showed a low level of the SHG signal in the polycrystalline state, and no nonlinear optical effect was detected in the fluid nematic state (N) either in the presence or absence of an orienting electric field. When frozen, the resulting thermodynamically unstable nematic glassy phase (glassyN) unexpectedly exhibited the second-order nonlinear optical properties, implying a partial polar order in the arrangement of the in-plane-aligned molecules in a liquid-crystal cell. The efficiency of the SHG was analyzed for two polarization configurations yielding the main component of the second-order nonlinear susceptibility χₓₓₓ(²)=2.3±0.3pmV⁻¹ along the nematic director x. A comparison of the experimental susceptibility with a hypothetical one estimated from the vectorial component of the molecular hyperpolarizability showed a relatively low degree of the spontaneous polar order. The dispersion of the principal refractive indices in the glassy state of HPTD was derived from dichroic absorption spectra using an interference fringe method and fitted with a Sellmeier-type equation. At 527nm the birefringence of HPTD is Δn=0.31.The authors acknowledge the Australian Research Council Discovery Project No. DP0556942 and the NSF Grant No. DMR-0111657 for financial support

The Myth of Emmetropia: Perception in Rhetorical Studies

This thesis sets up the problem of sight in a visual society, with the aim to answer how the visual makes itself known. The conversation starts on visuality, and where there are gaps in understanding. The first of two case studies examines the absence of sight, or blindness, both literal and figurative. Through a study of blind photographers and their work, this chapter examines the nature of perception, and how biological blindness may influence and inform our understanding of figurative blindness. The second case study examines what the improvement of damaged sight has to say about the rhetorical nature of images. This chapter examines various means of improving sight, using literal improvements to sight to understand figurative improvements in vision and perception. The fourth and final chapter seeks to sum up what has been discovered about the rhetorical nature of sight through the ends of the spectrum of sight

Keratoplastiken an der Augenklinik der Ludwig-Maximilians-Universität München zwischen 1994 und 1998

Ziel dieser Studie war eine retrospektive Analyse von 211 Keratoplastiken, die an der Universitäts-Augenklinik der Ludwig-Maximilians-Universität München im Zeitraum von 1994-1998 vorgenommen wurden. Die häufigsten Indikationen für eine Keratoplastik bildeten Keratokonus (35,6%), Endotheldekompensation nach CE/IOL (13,6%), Hornhautnarben (12,5%), Fuchs’sche Endotheldystrophie (11,0%) sowie ein perforiertes Hornhaut-Ulcus (8,4%). Es wurden 9,5% der Eingriffe als Re-Keratoplastiken vorgenommen. Der Anteil an Hochrisiko-Keratoplastiken betrug 28%. Der präoperative Visus lag bei über 70% aller Patienten unter 0,1. Sämtliche verwendeten Transplantate waren kurzzeitkonserviert, die Endothelzellzahl betrug in der Mehrzahl 2500-3000 Endothelzellen/mm², über 90 % aller verwendeten Transplantate wiesen eine gute bis sehr gute Qualität auf. Eine Transplantatabstoßung entwickelten 13,7% aller Transplantate. In der Gruppe der Transplantate mit einer Abstoßungsreaktion wurde eine endgültige Eintrübung des Transplantats signifikant häufiger beobachtet (48%) als in der Gruppe der Transplantate ohne eine Abstoßungsreaktion (11,5% ; p<0,001). Bei Re-Keratoplastik trat in 36,8% eine Transplantatabstoßung auf. Eine Transplantatabstoßung wurde in 43,5% der aufgrund einer Hochrisikosituation mit Ciclosporin A (CSA) behandelten Patienten beobachtet. Nach Fadenentfernung bzw. ≥ 2 Jahre postoperativ lag der Astigmatismus bei 34,3% der Patienten bei >0-3dpt. Einen Astigmatismus >3-6dpt wiesen 41,8% der Patienten auf und bei 23,9% der Patienten überstieg der Astigmatismus 6 dpt. Zum letzten Untersuchungszeitpunkt waren 85% aller Transplantate klar. Ein Literaturvergleich ergab im Wesentlichen eine Übereinstimmung unserer Ergebnisse mit den Arbeiten anderer Autoren. Verbesserungspotential besteht in der Unterdrückung bzw. Abwendung von Transplantatabstoßungsreaktionen. Verstärkte Aufmerksamkeit sollte einer konsequenten Langzeitevaluation gelten

Axially Chiral Stable Radicals: Resolution and Characterization ofBlatter Radical Atropisomers

Atropisomers of three Blatter radicals were obtainedby the addition of 8-substituted 1-naphthyllithiums to 3-phenyl and3-t-butylbenzo[e][1,2,4]triazine and separated by chiral high-performance liquid chromatography. Their absolute configurationswere assigned by a comparison of experimental and time-dependent density functional theory calculated electronic circulardichroism spectra. The free energy of activation,ΔG‡298, and thehalf life of racemization,t1/2, at 298 K were determined at∼25 kcal mol−1and <130 h, respectively. Intramolecularπ−πinteractionsin radicals were evident from single-crystal X-ray diffraction, density functional theory, and electrochemical analyses.This work was supported by the Foundation for Polish Science(TEAM/2016-3/24) and National Science Centre (2020/38/A/ST4/00597 and 2019/03/X/ST4/01147) grants. We thankProf. Piotr Chmielewski (Wrocław University) for assistancewith ECD measurements

3‑Substituted Benzo[e][1,2,4]triazines: Synthesis and Electronic Effects of the C(3) Substituent

A series of 19 structurally diverse C(3)-substituted derivatives of benzo[e][1,2,4]triazine were synthesized from 3-chloro- (1c) and 3-iodobenzo[e][1,2,4]triazine (1d) obtained in three steps from 2-nitroaniline in 37–55% yields. Nucleophilic aromatic substitution and metal-catalyzed (Pd, Cu) reactions led to functional derivatives that include alkyl (C5H11), (het)aryl (Ph, 2-thienyl, ferrocenyl), ArC≡C, amine (NHPh and morpholine), PO(OEt)2, sulfanyl (SBu-t), alkoxide (OEt, OMe), and CN. The synthesis of C(3)–CF3 derivative 1g via the Ruppert reaction with 1d and its 1-oxide analogue 2d led to the substitution followed by formal addition of HCF3 to the C═N bond. Pd-catalyzed carbonylation reactions of 1d and 2d did not give the corresponding C(3)-carboxylic acids. Therefore, acid 1f was obtained through hydrolysis of the CN. The substituent effect on the electronic structure of the benzo[e][1,2,4]triazine ring was investigated by spectroscopic methods (UV–vis and NMR) augmented with density functional theory calculations. Results show significant effect of the C(3) substituent on the π–π*(1) transition energy and good correlation of the 1H NMR chemical shift with the substituent constant σp. Molecular and crystal structures of six derivatives were established with the single-crystal X-ray diffraction method, and the substituent impact on the molecular geometry was investigated.This work was supported by the Foundation for Polish Science Grant (TEAM/2016-3/24) and National Science Foundation (XRD facility MRI-1626549)

Liquid crystalline radicals: discotic behavior of unsymmetrical derivatives of 1,3,5-triphenyl-6-oxoverdazyl

A series of six 6-oxoverdazyl (1[10]) substituted with a total of three 3,4,5-tri(decyloxy)phenyl and/or 3,4,5-tri(decylsulfanyl)phenyl groups was investigated by thermal, XRD, spectroscopic, magnetic and photovoltaic methods. The compounds exhibit columnar hexagonal (1[10]c, Colh), columnar hexagonal ordered (1[10]b, Colh(o)), columnar hexagonal 3D (1[10]a, 1[10]e and 1[10]f, Colh(3D)) or a sequence of two phases (1[10]b, Colh–Colh(3D)). The mesophase structure and stability and also thermochromism were investigated as a function of the number and distribution of decyloxy and decylsulfanyl substituents in the molecule. Thermal analysis demonstrated that the presence of the 3,4,5-tri(decyloxy)phenyl substituent in the C(3) position increases the phase stability. Spectroscopic analysis showed that only all-decyloxy derivative 1[10]b exhibits a hypsochromic shift upon Colh(o) formation, while all other compounds in the series show a modest bathochromic shift in the columnar phase relative to the isotropic phase. Magnetization investigation of 1[10]d demonstrated the paramagnetic behavior of isolated spins in isotropic and columnar phases. Negligible photocurrent was detected for 1[10]d in the columnar phase.This work was supported by NSF grants (CHEM-1214104). We thank Prof. Andrzej Twardowski for funding SQUID measurement