scholarly journals Recent Developments on Airborne Forward Looking Interferometer for the Detection of Wake Vortices

2012 ◽  
Author(s):  
Taumi Daniels ◽  
William Smith ◽  
Stanislav Kireev
Keyword(s):  
Wake Vortices ◽  
Recent Developments ◽  
Forward Looking

Vortex wakes of birds: recent developments using digital particle image velocimetry in a wind tunnel

2006 ◽  
Vol 56 (4) ◽  
pp. 535-549 ◽  
Author(s):  
◽  
◽  
◽  
Keyword(s):  
Particle Image Velocimetry ◽  
Wind Tunnel ◽  
Particle Image ◽  
Lift Coefficient ◽  
Time History ◽  
Digital Particle Image Velocimetry ◽  
Wake Vortices ◽  
Image Velocimetry ◽  
Recent Developments ◽  
Size And Morphology

AbstractA flying animal generates a trail of wake vortices that contain information about the time history and magnitude of aerodynamic forces developed on the wings and body. Methods for visualising and recording wake vortices have been developed, allowing quantitative measurements by digital particle image velocimetry (DPIV). Results from DPIV experiments in a wind tunnel are presented for four passerine species of differing size and morphology. The normalised vorticity and its integrated quantity, circulation (Γ) both decline gradually with increasing flight speed. The measured circulations are successfully explained by a simple aerodynamic model where a normalised circulation, Γ/Uc, represents half the time-averaged lift coefficient, which is >2 at 4 m s−1 for a thrush nightingale.

Recent Developments in the Institute's Domestic Macromodel

1989 ◽  
Vol 130 ◽  
pp. 47-51 ◽  
Author(s):  
Simon Wren-Lewis
Keyword(s):  
Econometric Model ◽  
Structural Characteristics ◽  
Model Version ◽  
Recent Developments ◽  
The Uk ◽  
Explicit Dynamic ◽  
Wage Equations ◽  
First Time ◽  
Forward Looking

The forecast published in this Review uses the latest vintage of the Institute's domestic econometric model, version 11.4. In comparison with the model described a year ago (Model 11.1, see Wren-Lewis, (1988)) some of the main developments are:1) The key price and wage equations are both forward looking, and are based on explicit dynamic theories of adjustment. This is perhaps the first time that a large quarterly econometric model has attempted to identify the structural characteristics of nominal inertia in the UK.

Recent Developments of Digital Cash Projects in Japan

2006 ◽  
pp. 194-214
Author(s):  
Nobuyoshi Yamori ◽  
Nobuyoshi Nishigaki
Keyword(s):  
Financial Institutions ◽  
Large Scale ◽  
Potential Effect ◽  
Bank Failures ◽  
Financial Difficulties ◽  
Recent Developments ◽  
Bubble Economy ◽  
Historical Developments ◽  
Remarkable Progress ◽  
Forward Looking

Most discussions and analyses regarding Japanese financial institutions during the 1990s have focused on the lingering effects of the collapse of the bubble economy, including huge non-performing loans and large-scale bank failures. Thus, it is natural for foreign observers to fail to acknowledge that many Japanese banks and other non-bank enterprises have conducted forward-looking projects despite their financial difficulties. One of these projects has been to develop digital cash technology and promote its usage. Because people in Japan tend to use cash for daily payments more often than people in other nations, if the Japanese begin using digital cash instead of traditional cash (i.e., Bank of Japan’s notes and coins), we anticipate that digital cash will have a larger potential effect on the society and economy in Japan than in other nations. Efforts to establish digital cash projects made discernible progress in the early 2000s, and digital cash is more commonly used now in Japan than in other IT-advanced countries. This chapter attempts to provide an overview of the recent development of digital cash projects in Japan, and to discuss the issues involved in the further growth of digital cash usage. This chapter is organized as follows. Section 1 presents the introduction. In Section 2, we explain the historical developments of digital cash projects in Japan. Section 3 discusses what factors led to remarkable progress in digital cash usage in the early 2000s. Section 4 describes the remaining issues that must be addressed for further growth of digital cash usage. Finally, Section 5 concludes the chapter.

A Promising Agenda

2017 ◽  
Author(s):  
G. William Domhoff
Keyword(s):  
Mind Wandering ◽  
Dream Content ◽  
Dream Recall ◽  
Neural Substrate ◽  
Recent Developments ◽  
Dream Research ◽  
Forward Looking

The ninth and final chapter returns to the forward-looking orientation of the first five chapters by presenting an agenda for future dream research, which makes use of recent developments in both communications (such as smartphones) and neuroimaging. It suggests how new and better studies can be done of dream recall, dream content, and the development of dreaming in children. It presents a novel way in which the neural substrate that very likely supports dreaming could be studied in greater detail by detecting the brief episodes of dreaming that are now known to occur during extended periods of drifting waking thought (e.g., during mind-wandering and daydreaming).

Trends in Electron Energy Loss Spectroscopy

1977 ◽  
Vol 35 ◽  
pp. 228-229
Author(s):  
C. Colliex ◽  
P. Trebbia
Keyword(s):  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Materials Science ◽  
Analytical Technique ◽  
Recent Developments ◽  
Quantitative Results ◽  
Electron Microscopes ◽  
Electron Energy Loss ◽  
Primary Electrons

The physical foundations for the use of electron energy loss spectroscopy towards analytical purposes, seem now rather well established and have been extensively discussed through recent publications. In this brief review we intend only to mention most recent developments in this field, which became available to our knowledge. We derive also some lines of discussion to define more clearly the limits of this analytical technique in materials science problems.The spectral information carried in both low ( 0<ΔE<100eV ) and high ( >100eV ) energy regions of the loss spectrum, is capable to provide quantitative results. Spectrometers have therefore been designed to work with all kinds of electron microscopes and to cover large energy ranges for the detection of inelastically scattered electrons (for instance the L-edge of molybdenum at 2500eV has been measured by van Zuylen with primary electrons of 80 kV). It is rather easy to fix a post-specimen magnetic optics on a STEM, but Crewe has recently underlined that great care should be devoted to optimize the collecting power and the energy resolution of the whole system.

Filaments and membranes in the mitotic apparatus

1983 ◽  
Vol 41 ◽  
pp. 544-547
Author(s):  
Kent McDonald
Keyword(s):  
Intermediate Filaments ◽  
Mitotic Spindle ◽  
Mitotic Apparatus ◽  
Light Microscope Level ◽  
Microtubule Associated Proteins ◽  
Recent Developments ◽  
Associated Proteins ◽  
Force Generator ◽  
Spindle Function ◽  
Antibody Technology

At the light microscope level the recent developments and interest in antibody technology have permitted the localization of certain non-microtubule proteins within the mitotic spindle, e.g., calmodulin, actin, intermediate filaments, protein kinases and various microtubule associated proteins. Also, the use of fluorescent probes like chlorotetracycline suggest the presence of membranes in the spindle. Localization of non-microtubule structures in the spindle at the EM level has been less rewarding. Some mitosis researchers, e.g., Rarer, have maintained that actin is involved in mitosis movements though the bulk of evidence argues against this interpretation. Others suggest that a microtrabecular network such as found in chromatophore granule movement might be a possible force generator but there is little evidence for or against this view. At the level of regulation of spindle function, Harris and more recently Hepler have argued for the importance of studying spindle membranes. Hepler also believes that membranes might play a structural or mechanical role in moving chromosomes.

Software pattern recognition applied to nanodiffraction patterns from a STEM instrument

1986 ◽  
Vol 44 ◽  
pp. 694-695
Author(s):  
G.Y. Fan ◽  
J.M. Cowley
Keyword(s):  
Image Processing ◽  
Pattern Recognition ◽  
Computer Software ◽  
Processing System ◽  
Light Level ◽  
Host Computer ◽  
Low Light ◽  
Image Processing System ◽  
Recent Developments ◽  
On Line

In recent developments, the ASU HB5 has been modified so that the timing, positioning, and scanning of the finely focused electron probe can be entirely controlled by a host computer. This made the asynchronized handshake possible between the HB5 STEM and the image processing system which consists of host computer (PDP 11/34), DeAnza image processor (IP 5000) which is interfaced with a low-light level TV camera, array processor (AP 400) and various peripheral devices. This greatly facilitates the pattern recognition technique initiated by Monosmith and Cowley. Software called NANHB5 is under development which, instead of employing a set of photo-diodes to detect strong spots on a TV screen, uses various software techniques including on-line fast Fourier transform (FFT) to recognize patterns of greater complexity, taking advantage of the sophistication of our image processing system and the flexibility of computer software.

High-resolution microscopy of twin boundaries in gold

1987 ◽  
Vol 45 ◽  
pp. 260-261
Author(s):  
William Krakow ◽  
David A. Smith
Keyword(s):  
High Resolution ◽  
Specimen Preparation ◽  
Gold Films ◽  
Boundary Area ◽  
Transmission Electron ◽  
Recent Developments ◽  
Tilt Boundaries ◽  
High Resolution Microscopy ◽  
Twist Boundaries

Recent developments in specimen preparation, imaging and image analysis together permit the experimental determination of the atomic structure of certain, simple grain boundaries in metals such as gold. Single crystal, ∼125Å thick, (110) oriented gold films are vapor deposited onto ∼3000Å of epitaxial silver on (110) oriented cut and polished rock salt substrates. Bicrystal gold films are then made by first removing the silver coated substrate and placing in contact two suitably misoriented pieces of the gold film on a gold grid. Controlled heating in a hot stage first produces twist boundaries which then migrate, so reducing the grain boundary area, to give mixed boundaries and finally tilt boundaries perpendicular to the foil. These specimens are well suited to investigation by high resolution transmission electron microscopy.

Recent developments in automated Transmission Electron MI

1989 ◽  
Vol 47 ◽  
pp. 46-47
Author(s):  
W.J. de Ruijter ◽  
P. Rez ◽  
David J. Smith
Keyword(s):  
Image Analysis ◽  
Computer Image ◽  
Lens Design ◽  
Computer Image Analysis ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Recent Developments ◽  
On Line ◽  
Routine Procedures ◽  
Near Future

There is growing interest in the on-line use of computers in high-resolution electron n which should reduce the demands on highly skilled operators and thereby extend the r of the technique. An on-line computer could obviously perform routine procedures hand, or else facilitate automation of various restoration, reconstruction and enhan These techniques are slow and cumbersome at present because of the need for cai micrographs and off-line processing. In low resolution microscopy (most biologic; primary incentive for automation and computer image analysis is to create a instrument, with standard programmed procedures. In HREM (materials researc computer image analysis should lead to better utilization of the microscope. Instru (improved lens design and higher accelerating voltages) have improved the interpretab the level of atomic dimensions (approximately 1.6 Å) and instrumental resolutior should become feasible in the near future.

Recent developments in low-voltage SEM of polymers

1993 ◽  
Vol 51 ◽  
pp. 866-867
Author(s):  
S.J. Krause ◽  
W.W. Adams
Keyword(s):  
Low Voltage ◽  
Chromatic Aberration ◽  
Thermal Electron ◽  
Analytical Technique ◽  
Recent Developments ◽  
Beam Currents ◽  
New Generation ◽  
First Time ◽  
Voltage Scanning ◽  
Beam Damage

Over the past decade low voltage scanning electron microscopy (LVSEM) of polymers has evolved from an interesting curiosity to a powerful analytical technique. This development has been driven by improved instrumentation and in particular, reliable field emission gun (FEG) SEMs. The usefulness of LVSEM has also grown because of an improved theoretical and experimental understanding of sample-beam interactions and by advances in sample preparation and operating techniques. This paper will review progress in polymer LVSEM and present recent results and developments in the field.In the early 1980s a new generation of SEMs produced beam currents that were sufficient to allow imaging at low voltages from 5keV to 0.5 keV. Thus, for the first time, it became possible to routinely image uncoated polymers at voltages below their negative charging threshold, the "second crossover", E2 (Fig. 1). LVSEM also improved contrast and reduced beam damage in sputter metal coated polymers. Unfortunately, resolution was limited to a few tenths of a micron due to the low brightness and chromatic aberration of thermal electron emission sources.

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