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The accuracy of different digital impression techniques and scan bodies for complete-arch implant-supported reconstructionsMizumoto, Ryan M. 08 October 2018 (has links)
No description available.
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Design for Testability Techniques to Optimize VLSI Test CostDonglikar, Swapneel B. 28 July 2009 (has links)
High test data volume and long test application time are two major concerns for testing scan based circuits. The Illinois Scan (ILS) architecture has been shown to be effective in addressing both these issues. The ILS achieves a high degree of test data compression thereby reducing both the test data volume and test application time. The degree of test data volume reduction depends on the fault coverage achievable in the broadcast mode. However, the fault coverage achieved in the broadcast mode of ILS architecture depends on the actual configuration of individual scan chains, i.e., the number of chains and the mapping of the individual flip-flops of the circuit to the respective scan chain positions. Current methods for constructing scan chains in ILS are either ad-hoc or use test pattern information from an a-priori automatic test pattern generation (ATPG) run. In this thesis, we present novel low cost techniques to construct ILS scan configuration for a given design. These techniques efficiently utilize the circuit topology information and try to optimize the flip-flop assignment to a scan chain location without much compromise in the fault coverage in the broadcast mode. Thus, they eliminate the need of an a-priori ATPG run or any test set information. In addition, we also propose a new scan architecture which combines the broadcast mode of ILS and Random Access Scan architecture to enable further test volume reduction on and above effectively configured conventional ILS architecture using the aforementioned heuristics with reasonable area overhead. Experimental results on the ISCAS'89 benchmark circuits show that the proposed ILS configuration methods can achieve on an average 5% more fault coverage in the broadcast mode and on average 15% more test data volume and test application time reduction than existing methods. The proposed new architecture achieves, on an average, 9% and 33% additional test data volume and test application time reduction respectively on top of our proposed ILS configuration heuristics. / Master of Science
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Accurate Determination of Nonlinear Optical Properties of Cadmium Magnesium TellurideLombardo, David 27 May 2015 (has links)
No description available.
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Registration algorithm optimized for simultaneous localization and mapping / Algorithme de référencement optimisé pour la localisation et la cartographie simultanéesPomerleau, François January 2008 (has links)
Building maps within an unknown environment while keeping track of the current position is a major step to accomplish safe and autonomous robot navigation. Within the last 20 years, Simultaneous Localization And Mapping (SLAM) became a topic of great interest in robotics. The basic idea of this technique is to combine proprioceptive robot motion information with external environmental information to minimize global positioning errors. Because the robot is moving in its environment, exteroceptive data comes from different points of view and must be expressed in the same coordinate system to be combined. The latter process is called registration. Iterative Closest Point (ICP) is a registration algorithm with very good performances in several 3D model reconstruction applications, and was recently applied to SLAM. However, SLAM has specific needs in terms of real-time and robustness comparatively to 3D model reconstructions, leaving room for specialized robotic mapping optimizations in relation to robot mapping. After reviewing existing SLAM approaches, this thesis introduces a new registration variant called Kd-ICP. This referencing technique iteratively decreases the error between misaligned point clouds without extracting specific environmental features. Results demonstrate that the new rejection technique used to achieve mapping registration is more robust to large initial positioning errors. Experiments with simulated and real environments suggest that Kd-ICP is more robust compared to other ICP variants. Moreover, the Kd-ICP is fast enough for real-time applications and is able to deal with sensor occlusions and partially overlapping maps. Realizing fast and robust local map registrations opens the door to new opportunities in SLAM. It becomes feasible to minimize the cumulation of robot positioning errors, to fuse local environmental information, to reduce memory usage when the robot is revisiting the same location. It is also possible to evaluate network constrains needed to minimize global mapping errors.
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A FREQUENCY SCAN/FOLLOWING SCAN TWOWAY CARRIER ACQUISITION METHOD FOR USB SYSTEMJiaxing, Liu, Hongjun, Yang 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper introduces a frequency scan/following scan twoway carrier acquisition method for
USB and its following scan slope decision algorithm. Some measures are used to improve
twoway acquisition speed such as selecting initiation direction and returning to zero in the
shortest path, which can be implemented by software. Theoretic analysis, mathematical
expression, design method and experiment results are provided. Practical engineering
application shows the twoway acquisition using this new method has many advantages such
as fast speed, low cost and programmability. The method has been used in Chinese USB
system widely.
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Experimental and numerical analysis of the dynamic load distribution in a corrugated packaging systemJamialahmadi, Arsalan January 2008 (has links)
<p>It is well known that transportation means high and varying loads for products as well as packages. To develop corrugated boxes with optimal design and efficient use of raw materials is crucial. Vibrations and shocks acting on pallets during transportation are transferred to the corrugated boxes and considerably reduce the integrity and life time of the boxes. The development of experimental and analytical tools for measurement and prediction of the influence of dynamic loads on the box performance, such as stacking strength and conservation of stacking pattern would therefore be of large practical importance. In order to develop such tools, it is important to know the load distribution between different boxes. This master thesis presents a technique for investigating these stresses based on a pressure sensitive film, which gives many data points. A series of tests using random and sinusoidal vibration testing have been done utilising this technique and results are presented for different positions on the pallet and for different box filling methods. Investigations performed on the vibrations of the boxes also demonstrate a pitch type of motion. A level-crossing study on the forces existing between the boxes shows a Rayleigh force distribution. A mathematical model is also proposed for simulation of a stacking system. Advantages and disadvantages with this technique and with the model are described. Comparison between the experimental and numerical results shows a proper correlation. Using the pressure sensitive film as a quantitative sensor and applying the recorded data for the statistical study of the contact forces existing in a stack of boxes gives useful and important results for further analysis of the fatigue life and vulnerable positions of boxes.</p><p> </p>
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A real-time parallel processing system for synthetic aperture sonarLawlor, Michael Andrew January 1997 (has links)
No description available.
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Applications of focal-series data in scanning-transmission electron microscopyJones, Lewys January 2013 (has links)
Since its development, the scanning transmission electron microscope has rapidly found uses right across the material sciences. Its use of a finely focussed electron probe rastered across samples offers the microscopist a variety of imaging and spectroscopy signals in parallel. These signals are individually intuitive to interpret, and collectively immensely powerful as a research tool. Unsurprisingly then, much attention is concentrated on the optical quality of the electron probes used. The introduction of multi-pole hardware to correct optical distortions has yielded a step-change in imaging performance; now with spherical and other remnant aberrations greatly reduced, larger probe forming apertures are suddenly available. Probes formed by such apertures exhibit a much improved and routinely sub-Angstrom diffraction-limited resolution, as well as a greatly increased probe current for spectroscopic work. The superb fineness of the electron beams and enormous magnifications now achievable make the STEM instrument one of the most sensitive scientific instruments developed by man, and this thesis will deal with two core issues that suddenly become important in this new aberration-corrected era. With this new found sensitivity comes the risk of imaging-distortion from outside influences such as acoustic or mechanical vibrations. These can corrupt the data in an unsatisfactory manner and counter the natural interpretability of the technique. Methods to identify and diagnose this distortion will be discussed, and a new technique developed to restore the corrupted data presented. Secondly, the subtleties of probe-shape in the multi-pole corrected STEM are extensively evaluated via simulation, with the contrast-transfer capabilities across defocus explored in detail. From this investigation a new technique of STEM focal-series reconstruction (FSR) is developed to compensate for the small remnant aberrations that still persist – recovering the sample object function free from any optical distortion. In both cases the methodologies were developed into automated computer codes and example restorations from the two techniques are shown (separately, although in principal the scan-corrected output is compatible with FSR). The performance of these results has been quantified with respect to several factors including; image resolution, signal-noise ratio, sample-drift, low frequency instability, and quantitative image intensity. The techniques developed are offered as practical tools for the microscopist wishing to push the performance of their instrument just that little bit further.
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Utvärdering och vidareutveckling av STAPL för användning inom inbäddad Boundary-Scan-baserad testHolmqvist, Johan January 2007 (has links)
<p>Antalet kretskort som monteras i multikortssystem, till exempel telekommunikationssystem, ökar ständigt. Samtidigt som ytmonteringstekniken och packningstekniken blir allt bättre utvecklas även tillverkningsmetoderna för olika integrerade komponenter, vilket medför att varje kretskort rymmer allt fler integrerade komponenter. Detta gör att testning av integrerade komponenter och multikortsystem blir alltmer komplex. En förutsättning för att kunna genomföra effektiv testning är standarder. Standarder över hur testning ska genomföras medför att en komponent som uppfyller kraven från en standard är direkt utbytbar mot en komponent från en annan tillverkare som uppfyller kraven från samma standard. En god standard bidrar även till att utvecklingen drivs åt samma håll istället för att varje tillverkare har sin egen lösning och ett eget gränssnitt, vilket dessutom leder till att ett antal olika gränssnittsomvandlare behövs för att koppla samman olika komponenter. Internal Joint Test Action Group (IJTAG) arbetar just nu med att ta fram en standard för inbäddade testinstrument på mikronivå. De inbäddade instrumenten kan stödja karaktärisering av komponenter likväl som strukturell och funktionell testning. På makronivå arbetar System Joint Test Action Group (SJTAG) med att ta fram en standard för testadministration. Den främsta uppgiften är att koppla samman IJTAG-standarden med systemtestadministrationen. Behovet av ett kommunikationsprotokoll mellan dessa båda är stort. I denna rapport utvärderas Standard Test and Programming Language (STAPL) i syfte att se hur det passar som länk mellan testmanager och inbäddade instrument. Vidare identifieras ett antal brister i STAPL och ett förslag på en vidareutveckling av språket tas fram. Denna vidareutveckling syftar till att göra språket mer dynamiskt och passande för inbäddad testning via Boundary-Scan-protokollet. Slutligen implementeras en demonstrator som består av mjukvara som exekveras på en PC och en Field Programmable Gate Array (FPGA) som tjänar som testobjekt.</p>
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Functional Neuroimaging in a Pediatric Case of Impaired AwarenessNicholas, Christopher Richard N 01 May 2010 (has links)
Disorders of consciousness (DOC) occur in severe cases of neurological disease and acquired brain injury, spanning the continuum from complete unresponsiveness (vegetative state) to partial conscious awareness with only erratic voluntary behavioral responses (minimally conscious state). Assessing the patient’s level of awareness of self and their environment through behavioral evaluation is notoriously difficult and may lead to misdiagnosis if residual cognitive function goes undetected. A number of studies (Di et al., 2007; Staffen et al., 2008; Coleman et al., 2007; Qin et al., 2010) applying brain-imaging methods to measure brain activity associated with processing self-referential stimuli (stimuli related to the self) have found similar responses between patients with DOC and healthy volunteers. The present study involved a unique pediatric patient with comorbid quadriplegia and non-communicative impaired awaress who underwent fMRI to explore brain activity associated with the auditory presentation of personally relevant language stimuli: the subject’s own name (SON) and a familiar voice (FV). Activation was observed in the left tranverse temporal gyrus across all auditory stimuli. Presentation of the SON revealed activation in the left ventromedial prefrontal cortex (vMPFC) and right dorsolateral prefrontal cortex (DLPFC) and presentation of the FV revealed activation in the left supramarginal gyrus. These findings provide evidence of preserved brain activity in this patient during the presentation of self-referential stimuli and therefore support the application of functional neuroimaging methods to detect residual brain activity in pediatric patients who display impaired awareness.
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