90,779 research outputs found
The crystal structure of thiourea nitrate
The structure of thiourea nitrate has been determined by three-dimensional X-ray methods. Both Cu Ke and Mo K~ data were obtained with a single-crystal diffractometer and the final R values are 4.9% and 5.5% respectively. The space group is P211m and there are two molecules in the unit cell. All atoms, including hydrogen, lie on mirror planes. The whole structure is built up of layers of atoms, the atoms within each layer being linked by a network of hydrogen bonds
Multi-modal Image Processing based on Coupled Dictionary Learning
In real-world scenarios, many data processing problems often involve
heterogeneous images associated with different imaging modalities. Since these
multimodal images originate from the same phenomenon, it is realistic to assume
that they share common attributes or characteristics. In this paper, we propose
a multi-modal image processing framework based on coupled dictionary learning
to capture similarities and disparities between different image modalities. In
particular, our framework can capture favorable structure similarities across
different image modalities such as edges, corners, and other elementary
primitives in a learned sparse transform domain, instead of the original pixel
domain, that can be used to improve a number of image processing tasks such as
denoising, inpainting, or super-resolution. Practical experiments demonstrate
that incorporating multimodal information using our framework brings notable
benefits.Comment: SPAWC 2018, 19th IEEE International Workshop On Signal Processing
Advances In Wireless Communication
Black String Entropy from Anomalous D-brane Couplings
The quantum corrections to the counting of statistical entropy for the
5+1-dimensional extremal black string in type-IIB supergravity with two
observers are studied using anomalous Wess-Zumino actions for the corresponding
intersecting D-brane description. The electric-magnetic duality symmetry of the
anomalous theory implies a new symmetry between D-string and D-fivebrane
sources and renders opposite sign for the RR charge of one of the intersecting
D-branes relative to that of the black string. The electric-magnetic symmetric
Hilbert space decomposes into subspaces associated with interior and exterior
regions and it is shown that, for an outside observer, the expectation value of
a horizon area operator agrees with the deviation of the classical horizon area
in going from extremal to near-extremal black strings.Comment: 12 pages, LaTeX; Corrections and clarifying comments adde
Polygraph: Automatically generating signatures for polymorphic worms
It is widely believed that content-signature-based intrusion detection systems (IDSes) are easily evaded by polymorphic worms, which vary their payload on every infection attempt. In this paper, we present Polygraph, a signature generation system that successfully produces signatures that match polymorphic worms. Polygraph generates signatures that consist of multiple disjoint content sub-strings. In doing so, Polygraph leverages our insight that for a real-world exploit to function properly, multiple invariant substrings must often be present in all variants of a payload; these substrings typically correspond to protocol framing, return addresses, and in some cases, poorly obfuscated code. We contribute a definition of the polymorphic signature generation problem; propose classes of signature suited for matching polymorphic worm payloads; and present algorithms for automatic generation of signatures in these classes. Our evaluation of these algorithms on a range of polymorphic worms demonstrates that Polygraph produces signatures for polymorphic worms that exhibit low false negatives and false positives. Ā© 2005 IEEE
Business integration models in the context of web services.
E-commerce development and applications have
been bringing the Internet to business and marketing
and reforming our current business styles and
processes. The rapid development of the Web, in
particular, the introduction of the semantic web and
web service technologies, enables business
processes, modeling and management to enter an
entirely new stage. Traditional web based business
data and transactions can now be analyzed,
extracted and modeled to discover new business
rules and to form new business strategies, let alone
mining the business data in order to classify
customers or products. In this paper, we investigate
and analyze the business integration models in the
context of web services using a micro-payment
system because a micro-payment system is
considered to be a service intensive activity, where
many payment tasks involve different forms of
services, such as payment method selection for
buyers, security support software, product price
comparison, etc. We will use the micro-payment case
to discuss and illustrate how the web services
approaches support and transform the business
process and integration model.
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