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Quantum cryptography, or quantum key distribution (QKD), provides a means of unconditionally secure communication. The security is in principle based on the fundamental laws of physics. Security proofs show that if quantum cryptography is appropriately implemented, even the most powerful eavesdropper cannot decrypt the message from a cipher. The implementations of quantum crypto-systems in real life may not fully comply with the assumptions made in the security proofs. Such discrepancy between the experiment and the theory can be fatal to the security of a QKD system. In this thesis we address a number of these discrepancies. A perfect single-photon source is often assumed in many security proofs. However, a weak coherent source is widely used in a real-life QKD implementation. Decoy state protocols have been proposed as a novel ap...
The two major classes of laminate joints are bonded and bolted. Often the two classes are combined as bonded-bolted joints. Several characteristics of fiber reinforced composite materials render them more susceptible to joint problems than conventional metals. These characteristics include weakness in in-plane shear, transverse tension/compression, interlaminar shear, and bearing strength relative to the strength and stiffness in the fiber direction. Studies on bolted joints of composite materials have been focused on joining assembly subject to in-plane loads. Modes of failure under these loading conditions are net-tension failure, cleavage tension failure, shear-out failure, bearing failure, etc. Although the studies of torque load can be found in literature, they mainly discussed the effect of the torque load on in-plane strength. E...
The existing design code for torque limit of bolted joints for composites at Marshall Space Flight Center is MSFC-STD-486B, which was originally developed in 1960s for metallic materials. The theoretical basis for this code was a simplified mechanics analysis, which takes into account only the bolt, nut and washers, but not the structural members to be connected. The assumption was that metallic materials would not fail due to the bearing stress at the contact area between washer and the mechanical member. This is true for metallic materials; but for composite materials the results could be completely different. Unlike most metallic materials, laminated composite materials have superior mechanical properties (such as modulus and strength) in the in-plane direction, but not in the out-of-plane, or through-the-thickness (TTT) direction. ...
There are many problems in China's rural financial system. The main ones are ambiguous orientation of functions by the financial institutions, inconsistency in the system of rural economic and social development, serious lack of financial resources, and low levels of management in rural financial institutions. To tackle these problems, we have to first recognize the significance of rural financial system reforms from a strategic point of view, and then we need to set up a proper framework for rural financial reforms and let the government play a leading role in rural financial reform and development.
A generalized quadratic form Elliptical distributions Generalized linear model Subclasses of elliptical distributions
This technical report presents the design, validation and evaluation of an efficient online fault tolerance technique for fault detection and recovery in presence of three TSV defects: voids, delamination between TSV and landing pad, and TSV short-to-substrate. The technique employs transition delay test for TSV fault detection. Fault recovery is carried out by employing redundant TSVs and rerouting input/output signals to fault-free TSVs. This technique is efficient because it requires small (2 x number of TSVs per group) number of clock cycles for fault detection and recovery. Using 65-nm technology, simulations are carried out using HSPICE and ModelSim to validate fault detection and recovery. Synthesized RTL model of this technique is used to evaluate the area overhead. It is shown that regular and redundant TSVs can be divided int...
Comment: 15 pages, no figure
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