63,155 research outputs found
Test exploration and validation using transaction level models
The complexity of the test infrastructure and test strategies in systems-on-chip approaches the complexity of the functional design space. This paper presents test design space exploration and validation of test strategies and schedules using transaction level models (TLMs). Since many aspects of testing involve the transfer of a significant amount of test stimuli and responses, the communication-centric view of TLMs suits this purpose exceptionally wel
A high speed Tri-Vision system for automotive applications
Purpose: Cameras are excellent ways of non-invasively monitoring the interior and exterior of vehicles. In particular, high speed stereovision and multivision systems are important for transport applications such as driver eye tracking or collision avoidance. This paper addresses the synchronisation problem which arises when multivision camera systems are used to capture the high speed motion common in such applications.
Methods: An experimental, high-speed tri-vision camera system intended for real-time driver eye-blink and saccade measurement was designed, developed, implemented and tested using prototype, ultra-high dynamic range, automotive-grade image sensors specifically developed by E2V (formerly Atmel) Grenoble SA as part of the European FP6 project – sensation (advanced sensor development for attention stress, vigilance and sleep/wakefulness monitoring).
Results : The developed system can sustain frame rates of 59.8 Hz at the full stereovision resolution of 1280 × 480 but this can reach 750 Hz when a 10 k pixel Region of Interest (ROI) is used, with a maximum global shutter speed of 1/48000 s and a shutter efficiency of 99.7%. The data can be reliably transmitted uncompressed over standard copper Camera-Link® cables over 5 metres. The synchronisation error between the left and right stereo images is less than 100 ps and this has been verified both electrically and optically. Synchronisation is automatically established at boot-up and maintained during resolution changes. A third camera in the set can be configured independently. The dynamic range of the 10bit sensors exceeds 123 dB with a spectral sensitivity extending well into the infra-red range.
Conclusion: The system was subjected to a comprehensive testing protocol, which confirms that the salient requirements for the driver monitoring application are adequately met and in some respects, exceeded. The synchronisation technique presented may also benefit several other automotive stereovision applications including near and far-field obstacle detection and collision avoidance, road condition monitoring and others.Partially funded by the EU FP6 through the IST-507231 SENSATION project.peer-reviewe
Electronic Structure Shift of Deep Nanoscale Silicon by SiO- vs. SiN-Embedding as Alternative to Impurity Doping
Conventional impurity doping of deep nanoscale silicon (dns-Si) used in ultra
large scale integration (ULSI) faces serious challenges below the 14 nm
technology node. We report on a new fundamental effect in theory and
experiment, namely the electronic structure of dns-Si experiencing energy
offsets of ca. 1 eV as a function of SiO- vs. SiN-embedding with a
few monolayers (MLs). An interface charge transfer (ICT) from dns-Si specific
to the anion type of the dielectric is at the core of this effect and arguably
nested in quantum-chemical properties of oxygen (O) and nitrogen (N) vs. Si. We
investigate the size up to which this energy offset defines the electronic
structure of dns-Si by density functional theory (DFT), considering interface
orientation, embedding layer thickness, and approximants featuring two Si
nanocrystals (NCs); one embedded in SiO and the other in SiN.
Working with synchrotron ultraviolet photoelectron spectroscopy (UPS), we use
SiO- vs. SiN-embedded Si nanowells (NWells) to obtain their energy
of the top valence band states. These results confirm our theoretical findings
and gauge an analytic model for projecting maximum dns-Si sizes for NCs,
nanowires (NWires) and NWells where the energy offset reaches full scale,
yielding to a clear preference for electrons or holes as majority carriers in
dns-Si. Our findings can replace impurity doping for n/p-type dns-Si as used in
ultra-low power electronics and ULSI, eliminating dopant-related issues such as
inelastic carrier scattering, thermal ionization, clustering, out-diffusion and
defect generation. As far as majority carrier preference is concerned, the
elimination of those issues effectively shifts the lower size limit of Si-based
ULSI devices to the crystalization limit of Si of ca. 1.5 nm and enables them
to work also under cryogenic conditions.Comment: 14 pages, 17 Figures with a total 44 graph
VETA x ray data acquisition and control system
We describe the X-ray Data Acquisition and Control System (XDACS) used together with the X-ray Detection System (XDS) to characterize the X-ray image during testing of the AXAF P1/H1 mirror pair at the MSFC X-ray Calibration Facility. A variety of X-ray data were acquired, analyzed and archived during the testing including: mirror alignment, encircled energy, effective area, point spread function, system housekeeping and proportional counter window uniformity data. The system architecture is presented with emphasis placed on key features that include a layered UNIX tool approach, dedicated subsystem controllers, real-time X-window displays, flexibility in combining tools, network connectivity and system extensibility. The VETA test data archive is also described
Dynamic delamination of aeronautic structural composites by using cohesive finite elements
Cohesive finite elements are used to model impact induced delamination prediction of T800/21M unidirectional laminated composite. DCB, ELS and MMB tests are used to identify cohesive element parameters. Results from experiments and numerical prediction of impact induced delamination by commercially available code LS-DYNA are compared
Operations planning simulation model extension study. Volume 5: Mariner Jupiter orbiter PL-12-A automated payload (upper stage used)
For abstract, see N75-20432
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