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An automated calibration method for non-see-through head mounted displays
Accurate calibration of a head mounted display (HMD) is essential both for research on the visual system and for realistic interaction with virtual objects. Yet, existing calibration methods are time consuming and depend on human judgements, making them error prone, and are often limited to optical see-through HMDs. Building on our existing approach to HMD calibration Gilson et al. (2008), we show here how it is possible to calibrate a non-see-through HMD. A camera is placed inside a HMD displaying an image of a regular grid, which is captured by the camera. The HMD is then removed and the camera, which remains fixed in position, is used to capture images of a tracked calibration object in multiple positions. The centroids of the markers on the calibration object are recovered and their locations re-expressed in relation to the HMD grid. This allows established camera calibration techniques to be used to recover estimates of the HMD display's intrinsic parameters (width, height, focal length) and extrinsic parameters (optic centre and orientation of the principal ray). We calibrated a HMD in this manner and report the magnitude of the errors between real image features and reprojected features. Our calibration method produces low reprojection errors without the need for error-prone human judgements
Japan and the East Asian financial crisis: patterns, motivations and instrumentalisation of Japanese regional economic diplomacy
At first sight, the East Asian financial crisis represents an instance of Japan failing the test of regional leadership - as evidenced by its abandonment of initial proposals for an Asian Monetary Fund (AMF) in the face of US and Chinese opposition in 1997. However, if a second look is taken, and one which is sensitised to the fundamental characteristics of its diplomacy, then Japan can be seen as far more effective in augmenting its regional leadership role than previously imagined. Indeed, this article demonstrates that Japanese policy-makers have resurrected, over the longer term and in different guises, AMF-like frameworks which provide a potential springboard for further regional cooperation. Hence, the aims of this article are twofold. The first is to demonstrate the overall efficacy of Japanese regional economic diplomacy, and its ability to control outcomes through steering East Asia towards enhanced monetary cooperation. The second is to explain the reasons behind Japan's distinctive policy approach towards the financial crisis and general lessons for understanding its foreign policy. The article seeks to do so by asking three fundamental questions about the 'what', 'why' and 'how' of Japan's regional role: 'what' in terms of the dominant behavioural patterns of Japan's economic diplomacy; 'why' in terms of the motivations for this behaviour; and 'how' in terms of Japan's instrumentalisation of its regional policy
Multi-modal information processing for visual workload relief
The simultaneous performance of two single-dimensional compensatory tracking tasks, one with the left hand and one with the right hand, is discussed. The tracking performed with the left hand was considered the primary task and was performed with a visual display or a quickened kinesthetic-tactual (KT) display. The right-handed tracking was considered the secondary task and was carried out only with a visual display. Although the two primary task displays had afforded equivalent performance in a critical tracking task performed alone, in the dual-task situation the quickened KT primary display resulted in superior secondary visual task performance. Comparisons of various combinations of primary and secondary visual displays in integrated or separated formats indicate that the superiority of the quickened KT display is not simply due to the elimination of visual scanning. Additional testing indicated that quickening per se also is not the immediate cause of the observed KT superiority
A novel and precise time domain description of MOSFET low frequency noise due to random telegraph signals
Nowadays, random telegraph signals play an important role in integrated
circuit performance variability, leading for instance to failures in memory
circuits. This problem is related to the successive captures and emissions of
electrons at the many traps stochastically distributed at the silicon-oxide
(Si-SiO2) interface of MOS transistors. In this paper we propose a novel
analytical and numerical approach to statistically describe the fluctuations of
current due to random telegraph signal in time domain. Our results include two
distinct situations: when the density of interface trap density is uniform in
energy, and when it is an u-shape curve as prescribed in literature, here
described as simple quadratic function. We establish formulas for relative
error as function of the parameters related to capture and emission
probabilities. For a complete analysis experimental u-shape curves are used and
compared with the theoretical aproach
Champion or Chump: Using a Book-Length Case Study to Evaluate a Mythical Principal
This study examined how 130 participants enrolled in the University of Northern Iowa (UNI) principalship program completed a standards-based evaluation after reading a book-length case study of a mythical principal. Application of the Iowa Standards for School Leaders (ISSL), which mirror the Interstate School Leadership Licensure Consortium (ISLLC) and Educational Leadership Constituency Council (ELCC) standards reveal widespread agreement on the principal\u27s performance related to vision, instruction, management, collaboration and politics. However, participants were distinctly split as to the mythical principal\u27s ethics. The authors discuss potential responses to literature that identify many programs as weak and inadequate by providing more authentic and rigorous experiences around ethics and other practical issues for preservice principals
User type certification for advanced flight control systems
Advanced avionics through flight management systems (FMS) coupled with autopilots can now precisely control aircraft from takeoff to landing. Clearly, this has been the most important improvement in aircraft since the jet engine. Regardless of the eventual capabilities of this technology, it is doubtful that society will soon accept pilotless airliners with the same aplomb they accept driverless passenger trains. Flight crews are still needed to deal with inputing clearances, taxiing, in-flight rerouting, unexpected weather decisions, and emergencies; yet it is well known that the contribution of human errors far exceed those of current hardware or software systems. Thus human errors remain, and are even increasing in percentage as the largest contributor to total system error. Currently, the flight crew is regulated by a layered system of certification: by operation, e.g., airline transport pilot versus private pilot; by category, e.g., airplane versus helicopter; by class, e.g., single engine land versus multi-engine land; and by type (for larger aircraft and jet powered aircraft), e.g., Boeing 767 or Airbus A320. Nothing in the certification process now requires an in-depth proficiency with specific types of avionics systems despite their prominent role in aircraft control and guidance
Flight simulator with spaced visuals
A flight simulator arrangement wherein a conventional, movable base flight trainer is combined with a visual cue display surface spaced a predetermined distance from an eye position within the trainer. Thus, three degrees of motive freedom (roll, pitch and crab) are provided for a visual proprioceptive, and vestibular cue system by the trainer while the remaining geometric visual cue image alterations are developed by a video system. A geometric approach to computing runway image eliminates a need to electronically compute trigonometric functions, while utilization of a line generator and designated vanishing point at the video system raster permits facile development of the images of the longitudinal edges of the runway
Matrix solutions of a noncommutative KP equation and a noncommutative mKP equation
Matrix solutions of a noncommutative KP and a noncommutative mKP equation
which can be expressed as quasideterminants are discussed. In particular, we
investigate interaction properties of two-soliton solutions.Comment: 2 figure
Maximum Confidence Quantum Measurements
We consider the problem of discriminating between states of a specified set
with maximum confidence. For a set of linearly independent states unambiguous
discrimination is possible if we allow for the possibility of an inconclusive
result. For linearly dependent sets an analogous measurement is one which
allows us to be as confident as possible that when a given state is identified
on the basis of the measurement result, it is indeed the correct state.Comment: 4 pages, 2 figure
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