An exploratory investigation of the effect of a plastic coating on the profile drag of a practical-metal-construction sailplane airfoil

The Langley low-turbulence pressure tunnel to determine the effect of a plastic coating on the profile drag of a practical-metal-construction sailplane airfoil was investigated. The model was tested with three surface configurations: (1) filled, painted, and sanded smooth; (2) rough bare metal; and (3) plastic-coated. The results are compared with data for the design airfoil (Wortmann FX 67-K-170/17) from another low-turbulence wind tunnel. The investigation was conducted at Reynolds numbers based on airfoil chord of 1.1 x 10 to the 6th power, 2.2 x 10 to the 6th power, and 3.3 x 10 to the 6th power at a Mach number of 0.10

Low-speed aerodynamic characteristics of a 13-percent-thick airfoil section designed for general aviation applications

Wind-tunnel tests were conducted to determine the low-speed section characteristics of a 13 percent-thick airfoil designed for general aviation applications. The results were compared with NACA 12 percent-thick sections and with the 17 percent-thick NASA airfoil. The tests were conducted ovar a Mach number range from 0.10 to 0.35. Chord Reynolds numbers varied from about 2,000,000 to 9,000,000

Apollo to Artemis: Mining 50-Year Old Records to Inform Future Human Lunar Landing Systems

Under the Artemis lunar exploration program, NASA is committed to landing American astronauts on the moon by 2024. While NASAs new Space Launch System rocket and Orion capsule will carry astronauts from Earth to the Gateway, the human lunar landing system has not yet been fully defined. As in the Apollo program, there are concerns for vehicle weight and internal volume such that seats may not be desirable, and standing during lunar descent and ascent may be a preferred engineering solution. With such a design, astronauts will experience +GZ (head-to-foot) accelerations during capsule accelerations, and it is unclear whether spaceflight deconditioned astronauts can tolerate these. Apollo astronauts stood during lunar descent and ascent, and the data contained in the early program records for those missions represent a unique resource that may provide insights to the cardiovascular stress associated with this human landing system design

A photoemission study of the surface carbonate species on Ag{110}

The electronic structure of the surface carbonate species adsorbed on Ag{110} has been studied with angle‐resolved photoemission using synchrotron radiation. Despite the low symmetry of the surface complex (Cs) and more than one azimuthal orientation of the vertical symmetry plane, it has been possible to assign the adsorbate‐induced levels. Recent semiempirical quantum chemical calculations have proved to be of considerable assistance in this process. The resonant behavior observed for the 3a‘ level is discussed in the context of photoelectron data for the free BF3 molecule, which is isoelectronic with CO2−3. The Cs symmetry pertaining in the present experiment is compared with the effective D3h symmetry observed in x‐ray‐absorption spectroscopy of the same system

Ecology and Management of Depredating Blackbirds in Ontario Field Corn

Blackbird damage to field corn in southwestern Ontario has been a problem for farmers for many years (Whitney 1954; Dyer 1968). Historically, Kent and Essex counties were the major corn-growing regions in Ontario, and the most significant centers of corn depredation by blackbirds were in these counties. However, the development of new short-season cultivars has afforded the expansion of field corn production and corn depredation problems throughout southern Ontario. The Ontario Ministry of the Environment (OME) provided funding commencing in 1976 in response to these increased instances of corn depredation for a 4-year research program on the importance, ecology and control of blackbirds

CHEMICAL CONTROL OF DEPREDATING BLACKBIRDS IN ONTARIO FIELD CORN

Corn depredation by red·winged blackbirds (Agelaius phoeniceus) has been an agricultural problem in southwestern Ontario for many years. Large marsh areas along the shoreline of Lakes Erie and St. Clair provide ideal habitat for breeding and roosting. Concurrently, the vast monocultural field corn acreages in Kent and Essex Counties have over the years been the centers for blackbird depredation in the province. The expansion of corn production into other areas of Ontario has, however, resulted in a province·wide distribution of damage, and substantial crop losses for specific individual farmers (Tyler and Kannenberg, 1980). The Ontario Ministry of the Environment (OME) provided funding for a four·year research program on the importance, ecology and control of blackbirds in 1976 following mounting concern by Ontario corn producers. Dyer (1968) completed a major study on red-winged blackbirds in Dover Township, Kent County during the period 1964-68; however, the evaluation of 4-AP efficacy was a minor component of the project (Dyer, 1976). Thus, the OME required efficacy data on 4-AP for current Ontario conditions for registration purposes, regardless of the 1972 registration in the U.S.A. Methiocarb (3,5-dimethyl-4(methylthio) phenol methylcarbamate) (Mesurol®, Mobay Chemical Corp.) was also a candidate compound because of the known taste aversion properties (Rcigers, 1974; Crase and Dehaven, 1976). Again, the OME required data on the efficacy of methiocarb as a bird repellent in ripening field corn. Research on the potential for lethal roost control was an initial objective; however, this component of chemical control was not pursued. Conversely, lethal control at foraging sites was not an initial objective, however, ecological studies completed (Somers et aI., 1981b) suggested that the use of toxicants in a corn field may have potential. Pilot studies using Starlicide® (Ralston-Purina Co.) and a-chloralose at foraging sites were completed to evaluate this hypothesis

Calibration and Validation of a Finite ELement Model of THor-K Anthropomorphic Test Device for Aerospace Safety Applications

The THOR anthropomorphic test device (ATD) has been developed and continuously improved by the National Highway Traffic Safety Administration to provide automotive manufacturers an advanced tool that can be used to assess the injury risk of vehicle occupants in crash tests. Recently, a series of modifications were completed to improve the biofidelity of THOR ATD [1]. The updated THOR Modification Kit (THOR-K) ATD was employed at Wright-Patterson Air Base in 22 impact tests in three configurations: vertical, lateral, and spinal [2]. Although a computational finite element (FE) model of the THOR had been previously developed [3], updates to the model were needed to incorporate the recent changes in the modification kit. The main goal of this study was to develop and validate a FE model of the THOR-K ATD. The CAD drawings of the THOR-K ATD were reviewed and FE models were developed for the updated parts. For example, the head-skin geometry was found to change significantly, so its model was re-meshed (Fig. 1a). A protocol was developed to calibrate each component identified as key to the kinematic and kinetic response of the THOR-K head/neck ATD FE model (Fig. 1b). The available ATD tests were divided in two groups: a) calibration tests where the unknown material parameters of deformable parts (e.g., head skin, pelvis foam) were optimized to match the data and b) validation tests where the model response was only compared with test data by calculating their score using CORrelation and Analysis (CORA) rating system. Finally, the whole ATD model was validated under horizontal-, vertical-, and lateral-loading conditions against data recorded in the Wright Patterson tests [2]. Overall, the final THOR-K ATD model developed in this study is shown to respond similarly to the ATD in all validation tests. This good performance indicates that the optimization performed during calibration by using the CORA score as objective function is not test specific. Therefore confidence is provided in the ATD model for uses in predicting response in test conditions not performed in this study such those observed in the spacecraft landing. Comparison studies with ATD and human models may also be performed to contribute to future changes in THOR ATD design in an effort to improve its biofidelity, which has been traditionally based on post-mortem human subject testing and designer experience

The structure of Cu(110) (2×3)–N; pseudo‐square reconstruction of a rectangular mesh substrate

The structure of the Cu(110)(2×3)–N phase has been investigated by parallel studies using 3‐keV Li+ and 2‐keV He+ion scattering and scanned energy mode normal emission N 1s photoelectron diffraction. The Li+ion scattering results provide clear evidence for anadsorbate‐induced reconstruction of the Cu surface and, in particular, indicate a shortening of the Cu–Cu atomic spacing along the 〈100〉 azimuth to a value of 2.7±0.1 Å, similar to the 〈110〉 spacing of 2.55 Å. A model of the surface consistent with this result involves a pseudo‐square Cu top atom layer with N atoms occupying alternate hollow sites leading to a local structure which is a 6% distorted Cu(100)c(2×2)–N phase. He+ion scattering data provides support for the N hollow adsorption sites. Scanned energy mode photoelectron diffraction is insensitive to the nature of the reconstruction but provides information on the local adsorption sites and, hence, on the lateral registry of the reconstructed overlayer and the underlying substrate

High resolution CT diagnosis of isolated fracture of the malleus handle.

We report a case of a 48-year-old woman with a sudden-onset unexplained conductive unilateral hearing loss. There was no improvement after a trial with systemic corticosteroids. On otomicroscopy, the right tympanic membrane showed an abnormal outline of the malleus handle. Pneumatic otoscopy revealed excessive movement of the umbo compared with the lateral process. Audiometric testing showed a conductive hearing loss in the right ear, with an average pure-tone audiometry of air conduction of 40 dB and a maximum air-bone gap of 45 dB at 500 Hz. Tuning fork tests confirmed conductive hearing loss. Tympanometry showed increased compliance in the right ear and an absent ipsilateral stapedial reflex in response to a broad-band stimulus. High resolution computed tomography (CT) imaging of the temporal bone was performed by a high-definition CT system (Discovery CT750 HD®, GE, Hounslow, England). MIP (Maximum Intensity Projection) coronal ultrafine (around 0.1 mm) reconstructions of the malleus revealed a small non-displaced isolated fracture of the malleus handle (Fig. A and B). On the left there was a continuous appearence of the middle ear ossicles. During surgery, the isolated fracture of the right malleus handle was visualised and an ossiculoplasty was performed using a hydroxylapatite bone cement (OtoMimix®, Biomet, Jacksonville, Florida) (Fig. C). Postoperatively, average pure-tone audiometry of air condition improved to 30 dB, and maximum air-bone gap improved to 35 dB at 500 Hz