1,018 research outputs found
Development Of A Preliminary Lifing Analysis Tool For The F135-PW-100 Engine
No full textIn the near future the Royal Netherlands Air Force will replace their fleet of F-16’s with the F-35. In the past the NLR has aided the Air Force with life cycle and deterioration analysis work on the F100-PW-220 engine, which powers the F-16. Understanding the physical system of the engine allows for on-condition maintenance. The same is preferred for the F135-PW-100 engine powering the F-35. Therefore, a preliminary lifing analysis tool has been developed for the F135-PW-100 engine rotor blades, based on open source literature. Aerospace Engineerin
0.85 PW laser operation at 3.3 Hz and high-contrast ultrahigh-intensity λ = 400 nm second-harmonic beamline
No full textWe demonstrate the generation of 0.85 PW, 30 fs laser pulses at a repetition rate of 3.3 Hz with a record average power of 85 W from a Ti:sapphire laser. The system is pumped by high-energy Nd:glass slab amplifiers frequency doubled in LiB3O5 (LBO). Ultrahigh-contrast λ = 400 nm femtosecond pulses were generated in KH2PO4 (KDP) with>40% efficiency. An intensity of 6.5 × 1021 W∕cm2 was obtained by frequency doubling 80% of the available Ti:sapphire energy and focusing the doubled light with an f∕2 parabola. This laser will enable highly relativistic plasma experiments to be conducted at high repetition rate
Shifting attention in viewer- and object-based reference frames after unilateral brain injury
No full textThe aims of the present study were to investigate the respective roles that object- and viewer-based reference frames play in reorienting visual attention, and to assess their influence after unilateral brain injury. To do so, we studied 16 right hemisphere injured (RHI) and 13 left hemisphere injured (LHI) patients. We used a cueing design that manipulates the location of cues and targets relative to a display comprised of two rectangles (i.e., objects). Unlike previous studies with patients, we presented all cues at midline rather than in the left or right visual fields. Thus, in the critical conditions in which targets were presented laterally, reorienting of attention was always from a midline cue. Performance was measured for lateralized target detection as a function of viewer-based (contra- and ipsilesional sides) and object-based (requiring reorienting within or between objects) reference frames. As expected, contralesional detection was slower than ipsilesional detection for the patients. More importantly, objects influenced target detection differently in the contralesional and ipsilesional fields. Contralesionally, reorienting to a target within the cued object took longer than reorienting to a target in the same location but in the uncued object. This finding is consistent with object-based neglect. Ipsilesionally, the means were in the opposite direction. Furthermore, no significant difference was found in object-based influences between the patient groups (RHI vs. LHI). These findings are discussed in the context of reference frames used in reorienting attention for target detection
Supplementary Data: Spectral Control via Multi-Species Effects in PW-Class Laser-Ion Acceleration
No full textSupplementary materials for our paper "Spectral Control via Multi-Species Effects in PW-Class Laser-Ion Acceleration".
Additional high-resolution, raw HDF5 files using the openPMD standard (DOI:10.5281/zenodo.1167843) increase simulation output data to 4.7 TByte and are available from the corresponding author upon reasonable request.This project received funding within the MEPHISTO project (BMBF-Förderkennzeichen 01IH16006C)
Wall-pressure-velocity transfer kernel in high Reynolds number turbulent channel flows
No full textSince wall-pressure fluctuations would form a practically-robust input to a real-time active controller of wall-bounded turbulence, it is of high practical interest to study the scaling behavior of the wall-pressure-velocity coupling. This work investigates the coupling of the wall-pressure fluctuations with the streamwise and wall-normal velocity fluctuations. Both the gain (or coherence) and phase spectra of the wall-pressure-velocity transfer kernel are assessed using a comprehensive database, available from direct numerical simulations of turbulent channel flow. With data spanning a decade in friction Reynolds number Reτ ∼ 550-5200, a 1D analysis (in terms of the streamwise wavelength, λx) reveals that the streamwise velocity and wall-pressure are most strongly coupled at a self-similar wall-scaling of λx/y ≈ 14. For the wall-normal velocity component, the strongest coupling appears at approximately half this ratio (λx/y ≈ 8.5). An analysis of the kernel's phase demonstrates that both the coherent fluctuations of streamwise and wall-normal velocity obey a forward-leaning inclination angle of α ≈ 30◦. When extending the analysis to 2D (as a function of λx and λz), the peak-coherence for pw and u still resides close to λx/y ≈ 14 and is reasonably symmetric around λx/λz = 2.3. The 2D coherence for pw and v peaks around λx/λz = 1.0. Both the 2D coherence for pw and u, and pw and v, adhere to a wall-scaling with y. Scaling behaviours identified in this work will aid the efficacy of real-time controllers, by for instance the implementation of data-derived FIR filters to only control velocity structures that are captured through wall-pressure measurements.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Aerodynamic
Kościół katedralny pw. Wniebowzięcia Najświętszej Maryi Panny i Polonia w Charkowie: krótki szkic historyczny (XIX wiek)
No full textCathedral church of Assumptoin of the Blessed Virgin Marry a short historical draft (19th century). The author of the article presents a short outline of the cathedral church of Assumption of the Blessed Virgin Marry in Kharkiv since the moment it was built to its ceremonial cosercation in June 26, 1892 by the bishop of Molyhowska Diocese Albin Simon. Building of the church has been shown on the background of functioning of Polish community in Kharkiv in the 19th century which from a small group of believers managed transform into an important part of the citizens of the city. The cathedral church of Assumption of the Blessed Virgin Marry was a rock for Poles’ activities leaving in Kharkiv. The church survived till today and it adrous the city centre as an architectural jewel.Kościół katedralny pw. Wniebowzięcia Najświętszej Maryi Panny i Polonia w Charkowie: krótki szkic historyczny (XIX wiek). Autorka w przedstawionym artykule przybliża krótki zarys historii kościoła katedralnego pw. Wniebowzięcia Najświętszej Maryi Panny w Charkowie od czasu jego wzniesienia do chwili jego uroczystego poświęcenia 26 lipca 1892 roku przez biskupa pomocniczego diecezji mohylowskiej Franciszka Albina Simona. Budowa świątyni została ukazana na tle funkcjonowania w Charkowie w XIX wieku społeczności polskiej, która z niewielkiej garstki wiernych zdołała przekształcić się w niezwykle istotną część składową mieszkańców miasta. Ostoją dla działalności Polaków mieszkających w Charkowie był kościół katedralny pw. Wniebowzięcia Najświętszej Maryi Panny, który przetrwał do czasów obecnych, i dziś, jako perła architektury sakralnej, zdobi centrum miasta
Perikinetics and sludge study for the decontamination of petroleum produced water (PW) using novel mucuna seed extract
No full text© 2016, The Author(s). cc-by-nc-ndIn this study, Mucuna flagellipes seed extract was applied in the coagulation–flocculation of produced water (PW). Process parameters such as pH, dosage, and settling time were investigated. Process kinetics was also studied. Instrumental characterization of mucuna seed (MS), mucuna seed coagulant (MSC), and post effluent treatment settled sludge (PTSS) were carried out. The optimum decontamination efficiency of 95 % was obtained at 1 g/L MSC dosage, PW pH of 2, and rate constant of 0.0001 (L/g/s). Characterization results indicated that MS, MSC, and PTSS were of network structure, primitive lattice, and thermally stable. It could be concluded that MSC would be potential biomass for the treatment of produced water under the experimental conditions
Wideband Modeling of CMOS Schottky Barrier Diode Detectors for THz Radiometry
No full textA complete system modeling and characterization of a wideband differential terahertz (THz) direct detector, integrated in a commercial CMOS technology, is presented. The detector consists of a recently developed double leaky-slot lens antenna that operates from 200 to 600 GHz in combination with a differential Schottky barrier diode (SBD) direct detection circuit. The proposed methodology, starting from low-frequency measurements on a standalone SBD, is able to adequately model the spectral radiometric performance. The system noise-equivalent power (NEP) is characterized from 325 to 500 GHz in excellent agreement with the proposed system model. The measured NEP, 20 pW/√Hz minimum and 90 pW/√Hz frequency averaged, is compromised with respect to the average NEP of 2.7 pW/√Hz that was initially predicted by simulations using the process design kit (PDK) model, since the available SBDs are operating beyond their cutoff frequency. The diodes and models provided by the PDK proved to be inaccurate in predicting circuit behavior at these high frequencies. By using the proposed analysis and modeling approaches, an accurate wideband antenna–detector codesign could be applied for future passive THz imaging applications based on CMOS technologies.Accepted author manuscriptTera-Hertz SensingElectronic
A general iterative method for spatial resolution improvement of digital images in spatial domain
No full textSpatial resolution improvement of digital images has significant applications in remote sensing and computer vision. In this paper, a general iterative method is proposed to improve the spatial resolution from low-resolution images in spatial domain. The general method of interpolation and simulated sampling is formed based on the iterative methods for signal reconstruction from nonuniform sampling and the methods of projection onto convex sets (POCS) by defining convex sets of the sampled images and projection onto the sets, and using a general parallel projection method to find the common points of the sets. The method can be applied to multiframe images with different spatial resolution, various image radiance, relative geometric distortion, additive random noise, and some other general imaging style. Some experiments with resolution test pattern and multiangular remote sensing images performed the convergence and the effectiveness of the algorithms.Computer Science, Software EngineeringCPCI-S(ISTP)
Kanon w architekturze cerkwi prawosławnej pw. Mądrości Bożej – Hagia Sophia w Białymstoku
No full textIn this article, the author analyzes the architectural features of the orthodox church of St. of God's Wisdom - Hagia Sophia in Bialystok. The author identifies the features of the building's architecture and relates them to the canons of designing this type of facility. Another point of reference is the archetype of Byzantine architecture - Hagia Sophia from Istanbul (former Constantinople). The aim of the research is to answer the questions whether the design of the temple in Bialystok has preserved the principles of shaping the form and detail of Byzantine architecture and whether the object has an original character. The research methods used by the author are the "in-situ" method and the analytical-comparative method.W niniejszym artykule autor poddaje analizie cechy architektoniczne obiektu cerkwi prawosławnej pw. Mądrości Bożej – Hagia Sophia w Białymstoku. Autor identyfikuje cechy architektury budynku i odnosi je do kanonów projektowania tego typu obiektów. Punktem odniesienia jest też archetyp architektury bizantyjskiej – obiekt Hagii Sophii z Istambułu (dawny Konstantynopol). Celem badawczym jest odpowiedź na pytania, czy w projekcie białostockiej świątyni zachowano zasady kształtowania formy i detalu architektury bizantyjskiej oraz czy obiekt ma charakter oryginalny. Metody badawcze zastosowane przez autora w trakcie badań to metoda „in-situ” oraz metoda analityczno-porównawcza
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