3,676 research outputs found
An intruder model for verifying termination in security protocols
We formally describe an intruder that is suitable for checking fairness properties of security protocols. The intruder is proved to be equivalent to the Dolev-Yao intruder that respects the resilient communication channels assumption, in the sense that, if a fairness property holds in one of these models, it also holds in the other
IS KUWAIT TV DIGLOSSIC? A SOCIOLINGUISTIC INVESTIGATION
Diglossia is a sociolinguistic term refers to the use of two varieties of one language in a given community; one is regarded as the high variety and the other as a low variety. This paper is a qualitative study thatinvestigates diglossia in various Kuwaiti TV stations. It attempts to mainly see if the two varieties are used differently whenever there is a change of topic in TV programs. Topics investigated include news, programs discussing political issues, cooking, sports, religion, and fashion. The researchers made sure that all programs chosen for investigation are presented by Kuwaitis. Data collected for this study relied mainly on observations and videotaping which took five months duration. Data was then phonetically transcribed and qualitatively analyzed.Speech extracts indicating the use of either H or L variety are demonstrated where necessary. The analysis showed that diglossia extensively exists in all the Kuwaiti TVchannels under investigation. Such a study may, to some extent, draw some generalizations about diglossia in Kuwait due to the fact that these channels present a variety of diglossic behaviors in different settings by different Kuwaiti speakers
Fast -NNG construction with GPU-based quick multi-select
In this paper we describe a new brute force algorithm for building the
-Nearest Neighbor Graph (-NNG). The -NNG algorithm has many
applications in areas such as machine learning, bio-informatics, and clustering
analysis. While there are very efficient algorithms for data of low dimensions,
for high dimensional data the brute force search is the best algorithm. There
are two main parts to the algorithm: the first part is finding the distances
between the input vectors which may be formulated as a matrix multiplication
problem. The second is the selection of the -NNs for each of the query
vectors. For the second part, we describe a novel graphics processing unit
(GPU) -based multi-select algorithm based on quick sort. Our optimization makes
clever use of warp voting functions available on the latest GPUs along with
use-controlled cache. Benchmarks show significant improvement over
state-of-the-art implementations of the -NN search on GPUs
Access Control Synthesis for Physical Spaces
Access-control requirements for physical spaces, like office buildings and
airports, are best formulated from a global viewpoint in terms of system-wide
requirements. For example, "there is an authorized path to exit the building
from every room." In contrast, individual access-control components, such as
doors and turnstiles, can only enforce local policies, specifying when the
component may open. In practice, the gap between the system-wide, global
requirements and the many local policies is bridged manually, which is tedious,
error-prone, and scales poorly.
We propose a framework to automatically synthesize local access control
policies from a set of global requirements for physical spaces. Our framework
consists of an expressive language to specify both global requirements and
physical spaces, and an algorithm for synthesizing local, attribute-based
policies from the global specification. We empirically demonstrate the
framework's effectiveness on three substantial case studies. The studies
demonstrate that access control synthesis is practical even for complex
physical spaces, such as airports, with many interrelated security
requirements
Competing Universalities in Kardar-Parisi-Zhang (KPZ) Growth Models
We report on the universality of height fluctuations at the crossing point of
two interacting (1+1)-dimensional Kardar-Parisi-Zhang (KPZ) interfaces with
curved and flat initial conditions. We introduce a control parameter p as the
probability for the initially flat geometry to be chosen and compute the phase
diagram as a function of p. We find that the distribution of the fluctuations
converges to the Gaussian orthogonal ensemble Tracy-Widom (TW) distribution for
p0.5. For
p=0.5 where the two geometries are equally weighted, the behavior is governed
by an emergent Gaussian statistics in the universality class of Brownian
motion. We propose a phenomenological theory to explain our findings and
discuss possible applications in nonequilibrium transport and traffic flow.Comment: 5 pages, 6 figures, Phys. Rev. Lett. (2019) (accepted
Information Surfaces in Systems Biology and Applications to Engineering Sustainable Agriculture
Systems biology of plants offers myriad opportunities and many challenges in
modeling. A number of technical challenges stem from paucity of computational
methods for discovery of the most fundamental properties of complex dynamical
systems. In systems engineering, eigen-mode analysis have proved to be a
powerful approach. Following this philosophy, we introduce a new theory that
has the benefits of eigen-mode analysis, while it allows investigation of
complex dynamics prior to estimation of optimal scales and resolutions.
Information Surfaces organizes the many intricate relationships among
"eigen-modes" of gene networks at multiple scales and via an adaptable
multi-resolution analytic approach that permits discovery of the appropriate
scale and resolution for discovery of functions of genes in the model plant
Arabidopsis. Applications are many, and some pertain developments of crops that
sustainable agriculture requires.Comment: 24 Pages, DoCEIS 1
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