3,507 research outputs found
Analysis of Key Wrapping APIs:Generic Policies, Computational Security
International audienceWe present an analysis of key wrapping APIs with generic policies. We prove that certain minimal conditions on policies are sufficient for keys to be indistinguishable from random in any execution of an API. Our result captures a large class of API policies, including both the hierarchies on keys that are common in the scientific literature and the non-linear dependencies on keys used in PKCS#11. Indeed, we use our result to propose a secure refinement of PKCS#11, assuming that the attributes of keys are transmitted as authenticated associated data when wrapping and that there is an enforced separation between keys used for wrapping and keys used for other cryptographic purposes. We use the Computationally Complete Symbolic Attacker developed by Bana and Comon. This model enables us to obtain computational guarantees using a simple proof with a high degree of modularity
Threshold Resummation Effects in the Associated Production of Chargino and Neutralino at Hadron Colliders
We investigate the QCD effects in the associated production of the chargino
and the neutralino, and , in the Minimal
Supersymmetric Standard Model (MSSM) at both the Fermilab Tevatron and the CERN
Large Hadron Collider (LHC). We include the next-to-leading order (NLO) QCD
corrections (including supersymmetric QCD) and the threshold resummation
effects. Our results show that, compared to the NLO predictions, the threshold
resummation effects can increase the total cross sections by 3.6% and 3.9% for
the associated production of and
at the LHC, respectively, and by 4.7% for
those of at the Tevatron. In the invariant
mass distributions the resummation effects are significant for large invariant
mass. The threshold resummation reduces the dependence of the total cross
sections at the LHC (Tevatron) on the renormalization/factorization scales to
5% (4%) from up to 7% (11%) at NLO.Comment: revised version with midifications, several references adde
Unilateral agenesis of the facial artery with compensation by a giant transverse facial artery
During routine dissections carried out in the course of our medical gross anatomy
work, an unusual structure was found unilaterally on the left side of an adult
male cadaver. Upon investigation, this was determined to be a hugely dilated
transverse facial artery. Also noted was the complete absence of the ipsilateral
facial artery. To our knowledge, this is the first report of complete agenesis and
not simply diminution of the facial artery with compensatory enlargement of the
transverse facial artery
Severe bilateral atrophy of the spinati muscles in a cadaver
During the routine dissection of a 62-year-old male cadaver, bilateral atrophy of
the supra and infraspinatus muscles was observed. The suprascapular nerves,
cervical spinal cord and surrounding muscles were found to be normal. We
propose that, in the face of normal histology and other normal shoulder girdle
muscles and normal nerves, this case represents an instance of Parsonage-Turner
syndrome. To our knowledge, this is the first report of bilateral spinati atrophy
in a cadaver
Projects in the Design and Construction of a Scanning Tunneling Microscope and UHV Sample Analysis Chamber
Thesis advisor: Vidya MadhavanThree projects have been undertaken during the design and the construction of a scanning tunneling microscope. The first project focuses on a method of testing the movement of piezoelectric ceramics by means of a modified Michelson interferometer. These tests determine the magnitude and the direction of motion on the scale of a few angstroms. These piezos are then used in moving the tip of the STM. The second project concerned the design of a surface analysis chamber to be used for thin film depositions. This chamber will operate at UHV levels and will produce samples to be examined by the STM. The final project dealt with the construction and testing of a feedback loop to be used in the e-beam heater during thin film depositions. This box monitors the current between the sample and the source modifying the voltage across the filament to ensure the current between the two remains constant, ensuring a constant deposition rate.Thesis (BS) — Boston College, 2004.Submitted to: Boston College. College of Arts and Sciences.Discipline: Physics.Discipline: College Honors Program
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