Search results for "General Computer Science"
showing 10 items of 895 documents
Growth of two-dimensional Au patches in graphene pores: A density-functional study
2017
Inspired by recent studies of various two-dimensional (2D) metals such as Au, Fe and Ag, we study the growth of two-dimensional gold patches in graphene pores by density-functional theory. We find that at room temperature gold atoms diffuse readily on top of both graphene and two-dimensional gold with energy barriers less than $0.5$ eV. Furthermore, gold atoms move without barriers from the top of graphene to its edge and from the top of 2D gold to its edge. The energy barriers are absent even at the interface of 2D gold and graphene, so that the gold atoms move effortlessly across the interface. We hope our demonstration for the propensity of diffusing gold atoms to grow 2D gold patches in…
Automatic landmark detection and 3D Face data extraction
2017
Abstract This paper contributes to 3D facial synthesis by presenting a novel method for parameterization using Landmark Point detection. The approach presented aims at improving facial recognition even in varying facial expressions, and missing data in 3D facial models. As such, the prime objective was to develop an automatically embedded process that can detect any frontal face in 3D face recognition systems, with face segmentation and surface curvature information. Using the hybrid interpolation method, experiments on facial landmarks were performed on 4950 images from Face Recognition Grand Challenge database (FRGC). Distinctive facial landmarks from the nose–tips, Limits mouth and two e…
The General Routing Problem polyhedron: Facets from the RPP and GTSP polyhedra
1998
[EN] In this paper we study the polyhedron associated with the General Routing Problem (GRP). This problem, first introduced by Orloff in 1974, is a generalization of both the Rural Postman Problem (RPP) and the Graphical Traveling Salesman Problem (GTSP) and, thus, is NP -hard. We describe a formulation of the problem such that from every non-trivial facet-inducing inequality for the RPP and GTSP polyhedra, we obtain facet-inducing inequalities for the GRP polyhedron, We describe a new family of facet-inducing inequalities for the GRP, the honeycomb constraints, which seem to be very useful for solving GRP and RPP instances. Finally, new classes of facets obtained by composition of facet-i…
Toward Optimal LSTM Neural Networks for Detecting Algorithmically Generated Domain Names
2021
Malware detection is a problem that has become particularly challenging over the last decade. A common strategy for detecting malware is to scan network traffic for malicious connections between infected devices and their command and control (C&C) servers. However, malware developers are aware of this detection method and begin to incorporate new strategies to go unnoticed. In particular, they generate domain names instead of using static Internet Protocol addresses or regular domain names pointing to their C&C servers. By using a domain generation algorithm, the effectiveness of the blacklisting of domains is reduced, as the large number of domain names that must be blocked g…
Optical sectioning microscopy through single-shot Lightfield protocol
2020
Optical sectioning microscopy is usually performed by means of a scanning, multi-shot procedure in combination with non-uniform illumination. In this paper, we change the paradigm and report a method that is based in the light field concept, and that provides optical sectioning for 3D microscopy images after a single-shot capture. To do this we fi rst capture multiple orthographic perspectives of the sample by means of Fourier-domain integral microscopy (FiMic). The second stage of our protocol is the application of a novel refocusing algorithm that is able to produce optical sectioning in real time, and with no resolution worsening, in the case of sparse f luorescent samples.We provide the…
Minimal change list for Lucas strings and some graph theoretic consequences
2005
AbstractWe give a minimal change list for the set of order p length-n Lucas strings, i.e., the set of length-n binary strings with no p consecutive 1's nor a 1ℓ prefix and a 1m suffix with ℓ+m⩾p. The construction of this list proves also that the order p n-dimensional Lucas cube has a Hamiltonian path if and only if n is not a multiple of p+1, and its second power always has a Hamiltonian path.
Operational and financial effectiveness of e-collaboration tools in supply chain integration
2004
This paper develops a comprehensive model of supply chain integration and uses it to analyze and assess the operational and financial effectiveness of different e-collaboration tools at various levels of supply chain integration. This model is also used to evaluate the importance of the sequence in which e-collaboration tools are adopted in supply chain integration. Computational results from a validated system dynamics simulation model with different implementation sequences of e-collaboration tools and different financial scenarios show that local financial constraints can also severely impact operational and financial performance of the entire supply chain. (C) 2003 Elsevier B.V. All rig…
PANORMUS-SPH. A new Smoothed Particle Hydrodynamics solver for incompressible flows
2015
Abstract A new Smoothed Particle Hydrodynamics (SPH) solver is presented, fully integrated within the PANORMUS package [7] , originally developed as a Finite Volume Method (FVM) solver. The proposed model employs the fully Incompressible SPH approach, where a Fractional Step Method is used to make the numerical solution march in time. The main novelty of the proposed model is the use of a general and highly flexible procedure to account for different boundary conditions, based on the discretization of the boundary surfaces with a set of triangles and the introduction of mirror particles with suitable hydrodynamic properties. Both laminar and turbulent flows can be solved (the latter using t…
Quantum inductive inference by finite automata
2008
AbstractFreivalds and Smith [R. Freivalds, C.H. Smith Memory limited inductive inference machines, Springer Lecture Notes in Computer Science 621 (1992) 19–29] proved that probabilistic limited memory inductive inference machines can learn with probability 1 certain classes of total recursive functions, which cannot be learned by deterministic limited memory inductive inference machines. We introduce quantum limited memory inductive inference machines as quantum finite automata acting as inductive inference machines. These machines, we show, can learn classes of total recursive functions not learnable by any deterministic, nor even by probabilistic, limited memory inductive inference machin…
Finite automata on timed ω-trees
2003
AbstractIn the last decade Alur and Dill introduced a model of automata on timed ω-sequences which extends the traditional models of finite automata. In this paper, we present a theory of timed ω-trees which extends both the theory of timed ω-sequences and the theory of ω-trees. The main motivation is to introduce a new way of specifying real-time systems and provide tools for studying decidability problems in related fields. We focus on the decision problems and their applications in system verification and synthesis.