4,369 research outputs found
Bank-to-turn control technology survey for homing missiles
The potential advantages of bank-to-turn control are summarized. Recent and current programs actively investigating bank-to-turn steering are reviewed and critical technology areas concerned with bank-to-turn control are assessed
Exploring computer-generated line graphs through virtual touch
This paper describes the development and evaluation of a haptic interface designed to provide access to line graphs for blind or visually impaired people. Computer-generated line graphs can be felt by users through the sense of touch produced by a PHANToM force feedback device. Experiments have been conducted to test the effectiveness of this interface with both sighted and blind people. The results show that sighted and blind people have achieved about 89.95% and 86.83% correct answers respectively in the experiment
Diffuse somatostatin-immunoreactive D-cell hyperplasia in the stomach and duodenum
This paper presents the first case of extensive, diffuse, somatostatin- immunoreactive D-cell hyperplasia in the human stomach and duodenum. It occurred in a 37-yr-old woman, who showed clinical signs of dwarfism, obesity, dryness of the mouth, and goiter. The density of the distribution of D cells was increased 39-fold in the stomach fundus, 23- fold in the proximal antrum, 25-fold in the distal antrum, and 31-fold in the upper duodenum in comparison with normal values. At the same time, the gastrin-immunoreactive cells were increased 2.3-fold in the antrum. Although the range in size of the D cells was within normal limits in all regions examined, the G cells showed pronounced hypertrophy of up to 127%. A possible relationship between the immuno- histochemical findings and the clinical picture is discussed
Constructing sonified haptic line graphs for the blind student: first steps
Line graphs stand as an established information visualisation and analysis technique taught at various levels of difficulty according to standard Mathematics curricula. It has been argued that blind individuals cannot use line graphs as a visualisation and analytic tool because they currently primarily exist in the visual medium. The research described in this paper aims at making line graphs accessible to blind students through auditory and haptic media. We describe (1) our design space for representing line graphs, (2) the technology we use to develop our prototypes and (3) the insights from our preliminary work
John Bankhead Magruder and the Defense of the Virginia Peninsula, 1861-1862
The viability of the Confederacy depended on its ability to organize a government and military defense force. Two early concerns were the operation of Gosport Naval Shipyard and protection of the Confederate capital at Richmond. Poised between them was Fortress Monroe.
With undisputed Union mastery of the Chesapeake Bay, Fortress Monroe was a constant reminder of the tentative security of these critical points. The man chosen to protect the Peninsula was Virginian, John Bankhead Magruder. Less than one year later, his efforts were denigrated by Commanding General Joseph E. Johnston who wanted to pursue his own strategic plan.
Under constant stress, Magruder performed with alacrity. Although the Peninsula was evacuated in May 1862, Magruder did an admirable job of defense. Magruder\u27s place in history has been discolored by perceived battlefield failures at Savage\u27s Station and Malvern Hill. These are an unfortunate footnote to an otherwise solid military career
Imaging of microwave fields using ultracold atoms
We report a technique that uses clouds of ultracold atoms as sensitive,
tunable, and non-invasive probes for microwave field imaging with micrometer
spatial resolution. The microwave magnetic field components drive Rabi
oscillations on atomic hyperfine transitions whose frequency can be tuned with
a static magnetic field. Readout is accomplished using state-selective
absorption imaging. Quantitative data extraction is simple and it is possible
to reconstruct the distribution of microwave magnetic field amplitudes and
phases. While we demonstrate 2d imaging, an extension to 3d imaging is
straightforward. We use the method to determine the microwave near-field
distribution around a coplanar waveguide integrated on an atom chip.Comment: 11 pages, 4 figure
Træplantning og Havevæsen i Jylland med særligt Hensyn til det jydske Haveselskab.
Træplantning og Havevæsen i Jylland med særligt Hensyn til det jydske Haveselskab
Towards designing robust coupled networks
Natural and technological interdependent systems have been shown to be highly
vulnerable due to cascading failures and an abrupt collapse of global
connectivity under initial failure. Mitigating the risk by partial
disconnection endangers their functionality. Here we propose a systematic
strategy of selecting a minimum number of autonomous nodes that guarantee a
smooth transition in robustness. Our method which is based on betweenness is
tested on various examples including the famous 2003 electrical blackout of
Italy. We show that, with this strategy, the necessary number of autonomous
nodes can be reduced by a factor of five compared to a random choice. We also
find that the transition to abrupt collapse follows tricritical scaling
characterized by a set of exponents which is independent on the protection
strategy
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