Effect of an alternate winglet on the pressure and spanwise load distributions of a first generation jet transport wing

Pressure and spanwise load distributions on a first-generation jet transport semispan model at subsonic speeds are presented. The wind tunnel data were measured for the wing with and without an alternate winglet. The results show that the winglet affected outboard wing pressure distributions and increased the spanwise loads near the tip

Effect of winglets on a first-generation jet transport wing. 1: Longitudinal aerodynamic characteristics of a semispan model at subsonic speeds

The effects of winglets and a simple wing-tip extension on the aerodynamic forces and moments and the flow-field cross flow velocity vectors behind the wing tip of a first generation jet transport wing were investigated in the Langley 8-foot transonic pressure tunnel using a semi-span model. The test was conducted at Mach numbers of 0.30, 0.70, 0.75, 0.78, and 0.80. At a Mach number of 0.30, the configurations were tested with combinations of leading- and trailing-edge flaps

Effect of Winglets on a First-Generation Jet Transport Wing. 2: Pressure and Spanwise Load Distributions for a Semispan Model at High Subsonic Speeds

Pressure and spanwise load distributions on a first-generation jet transport semispan model at high subsonic speeds are presented for the basic wing and for configurations with an upper winglet only, upper and lower winglets, and a simple wing-tip extension. Selected data are discussed to show the general trends and effects of the various configurations

CAFE: Calar Alto Fiber-fed Echelle spectrograph

We present here CAFE, the Calar Alto Fiber-fed Echelle spectrograph, a new instrument built at the Centro Astronomico Hispano Alem\'an (CAHA). CAFE is a single fiber, high-resolution ($R\sim$70000) spectrograph, covering the wavelength range between 3650-9800\AA. It was built on the basis of the common design for Echelle spectrographs. Its main aim is to measure radial velocities of stellar objects up to $V\sim$13-14 mag with a precision as good as a few tens of $m s^{-1}$. To achieve this goal the design was simplified at maximum, removing all possible movable components, the central wavelength is fixed, so the wavelentgth coverage; no filter wheel, one slit and so on, with a particular care taken in the thermal and mechanical stability. The instrument is fully operational and publically accessible at the 2.2m telescope of the Calar Alto Observatory. In this article we describe (i) the design, summarizing its manufacturing phase; (ii) characterize the main properties of the instrument; (iii) describe the reduction pipeline; and (iv) show the results from the first light and commissioning runs. The preliminar results indicate that the instrument fulfill the specifications and it can achieve the foreseen goals. In particular, they show that the instrument is more efficient than anticipated, reaching a $S/N\sim$20 for a stellar object as faint as $V\sim$14.5 mag in $\sim$2700s integration time. The instrument is a wonderful machine for exoplanetary research (by studying large samples of possible systems cotaining massive planets), galactic dynamics (high precise radial velocities in moving groups or stellar associations) or astrochemistry.Comment: 12 pages, 23 figures; Acepted for publishing in A&A, 201

Luminescent hyperbolic metasurfaces.

When engineered on scales much smaller than the operating wavelength, metal-semiconductor nanostructures exhibit properties unobtainable in nature. Namely, a uniaxial optical metamaterial described by a hyperbolic dispersion relation can simultaneously behave as a reflective metal and an absorptive or emissive semiconductor for electromagnetic waves with orthogonal linear polarization states. Using an unconventional multilayer architecture, we demonstrate luminescent hyperbolic metasurfaces, wherein distributed semiconducting quantum wells display extreme absorption and emission polarization anisotropy. Through normally incident micro-photoluminescence measurements, we observe absorption anisotropies greater than a factor of 10 and degree-of-linear polarization of emission >0.9. We observe the modification of emission spectra and, by incorporating wavelength-scale gratings, show a controlled reduction of polarization anisotropy. We verify hyperbolic dispersion with numerical simulations that model the metasurface as a composite nanoscale structure and according to the effective medium approximation. Finally, we experimentally demonstrate >350% emission intensity enhancement relative to the bare semiconducting quantum wells

Abundance and size of birds determine the position of the species in plant-frugivore interaction networks in fragmented forests

Abstract The relationships between frugivorous animals and plants are of vital importance particularly in tropical forests. The way species interact and how they are organized within interaction networks could be determined by their ecological and morphological characteristics. This study evaluates the hypothesis that the topological position of species within an interaction network is determined by their degree of frugivory, body size, and abundance. Thus, we constructed the frugivory network between birds and plants in a rainforest fragment in northwestern Colombia. The position of the species within the network was calculated based on three centrality measures (degree, betweenness, and closeness), and its association with relative abundance, degree of frugivory, and body size of each bird species was evaluated by means of a generalized linear model. We found that the species that were most abundant and had the smallest body size had central positions in the interaction network. This pattern is contrary to what has been observed in pristine forests, where species with large body size are more important for network stability. Our results suggest that forest fragmentation modifies the roles of species within the network structure, in part, due to changes in the makeup of the original frugivore community. The information presented may be useful to evaluate the effects of the loss of species as a result of anthropic actions, with the aim of generating ecosystem restoration strategies

Effect of winglets on a first-generation jet transport wing. 3: Pressure and spanwise load distributions for a semispan model at Mach 0.30

Pressure and spanwise load distributions on a first-generation jet transport semispan model at a Mach number of 0.30 are given for the basic wing and for configurations with an upper winglet only, upper and lower winglets, and a simple wing-tip extension. To simulate second-segment-climb lift conditions, leading- and/or trailing-edge flaps were added to some configurations

Development and Testing of a Real-Time LoRawan Sniffer Based on GNU-Radio

En este documento se muestran las vulnerabilidades presentes en una red de sensores inalámbricas implementada sobre una red de área amplia de largo alcance (LoRaWAN por sus siglas en inglés) LoRaWAN y se identifican los posibles ataques que se podrían realizar a la red usando sniffing y/o replay. Los ataques a la red se realizaron implementando un analizador de protocolos (Sniffer) para capturar los paquetes. El Sniffer se implementó utilizando el hardware RTL2832U y se visualizó en Wireshark, a través de GNU-Radio. Las pruebas mostraron que se pueden amenazar la disponibilidad y confidencialidad de los datos a través de ataques de replay con verificación en el LoRa server utilizando hardware HackRF One y GNU-Radio. Aunque la especificación LoRaWAN tiene contadores para evitar ataques de replay, bajo condiciones adecuadas se lograría vulnerar la red llegando a realizar la denegación del servicio del nodo en el servidor.This paper shows the vulnerabilities present in a wireless sensor network implemented over a long-range wide area network (LoRaWAN) LoRaWAN, and identifies possible attacks that could be made to the network using sniffing and/or replay. Attacks on the network were performed by implementing a protocol analyzer (Sniffer) to capture packets. The Sniffer was implemented using the RTL2832U hardware and visualized in Wireshark, through GNU-Radio. Tests showed that data availability and confidentiality could be threatened through replay attacks with LoRa server verification using HackRF One and GNU-Radio hardware. Although the LoRaWAN specification has, frame counters to avoid replay attacks, under given the right conditions, this measure could be violated even deny service to the node on the server

Innovative Directions in Mental Health Assessment Part III: Use of Interactive Video Technology in Assessment: A Research Project

This article will report the steps and procedures implemented in the development and testing of the Diagnostic Interview Schedule for the Deaf-IV(DDIS-IV). The DDIS-IV is a standardized mental health assessment instrument developed for use with individuals who are deaf, it is self-administered in American Sign Language (ASL) on laptop computer. This research is supported by a Small Business Innovations Research Grant from the National Institute of Mental Health. The translation procedure consisted of two translation teams, advisors, and back translation. The technological procedure included the digital videotaping of assessment items in ASL, the use of interactive video software and the development of a data base and scoring program. During the testing phase, individuals who are deaf and receiving inpatient and outpatient mental health services will be tested two times, once using the self-administered version of the instrument and the second time receiving the same test in ASL by a mental health clinician

Emerging properties of financial time series in the “Game of Life”

We explore the spatial complexity of Conway’s “Game of Life,” a prototypical cellular automaton by means of a geometrical procedure generating a two-dimensional random walk from a bidimensional lattice with periodical boundaries. The one-dimensional projection of this process is analyzed and it turns out that some of its statistical properties resemble the so-called stylized facts observed in financial time series. The scope and meaning of this result are discussed from the viewpoint of complex systems. In particular, we stress how the supposed peculiarities of financial time series are, often, overrated in their importance