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Smart Computer Security Audit: Reinforcement Learning with a Deep Neural Network Approximator
A significant challenge in modern computer security is the growing skill gap as intruder capabilities increase, making it necessary to begin automating elements of penetration testing so analysts can contend with the growing number of cyber threats. In this paper, we attempt to assist human analysts by automating a single host penetration attack. To do so, a smart agent performs different attack sequences to find vulnerabilities in a target system. As it does so, it accumulates knowledge, learns new attack sequences and improves its own internal penetration testing logic. As a result, this agent (AgentPen for simplicity) is able to successfully penetrate hosts it has never interacted with before. A computer security administrator using this tool would receive a comprehensive, automated sequence of actions leading to a security breach, highlighting potential vulnerabilities, and reducing the amount of menial tasks a typical penetration tester would need to execute. To achieve autonomy, we apply an unsupervised machine learning algorithm, Q-learning, with an approximator that incorporates a deep neural network architecture. The security audit itself is modelled as a Markov Decision Process in order to test a number of decisionmaking strategies and compare their convergence to optimality. A series of experimental results is presented to show how this approach can be effectively used to automate penetration testing using a scalable, i.e. not exhaustive, and adaptive approach
The model equation of soliton theory
We consider an hierarchy of integrable 1+2-dimensional equations related to
Lie algebra of the vector fields on the line. The solutions in quadratures are
constructed depending on arbitrary functions of one argument. The most
interesting result is the simple equation for the generating function of the
hierarchy which defines the dynamics for the negative times and also has
applications to the second order spectral problems. A rather general theory of
integrable 1+1-dimensional equations can be developed by study of polynomial
solutions of this equation under condition of regularity of the corresponding
potentials.Comment: 17
Towards a theory of differential constraints of a hydrodynamic hierarchy
We present a theory of compatible differential constraints of a hydrodynamic
hierarchy of infinite-dimensional systems. It provides a convenient point of
view for studying and formulating integrability properties and it reveals some
hidden structures of the theory of integrable systems. Illustrative examples
and new integrable models are exhibited.Comment: Published by JNMP at http://www.sm.luth.se/math/JNMP
FeNi-based magnetoimpedance multilayers: Tailoring of the softness by magnetic spacers
The microstructure and magnetic properties of sputtered permalloy films and FeNi(170 nm)/X/FeNi(170 nm) (X=Co, Fe, Gd, Gd-Co) sandwiches were studied. Laminating of the thick FeNi film with various spacers was done in order to control the magnetic softness of FeNi-based multilayers. In contrast to the Co and Fe spacers, Gd and Gd-Co magnetic spacers improved the softness of the FeNi/X/FeNi sandwiches. The magnetoimpedance responses were measured for [FeNi/Ti(6 nm)] 2/FeNi and [FeNi/Gd(2 nm)] 2/FeNi multilayers in a frequency range of 1-500 MHz: for all frequencies under consideration the highest magnetoimpedance variation was observed for [FeNi/Gd(2 nm)] 2/FeNi multilayers. © 2012 American Institute of Physics
`Interpolating' differential reductions of multidimensional integrable hierarchies
We transfer the scheme of constructing differential reductions, developed
recently for the case of the Manakov-Santini hierarchy, to the general
multidimensional case. We consider in more detail the four-dimensional case,
connected with the second heavenly equation and its generalization proposed by
Dunajski. We give a characterization of differential reductions in terms of the
Lax-Sato equations as well as in the framework of the dressing method based on
nonlinear Riemann-Hilbert problem.Comment: Based on the talk at NLPVI, Gallipoli, 15 page
Manage entropy in Architectural Projects: assuming commitments and ordering diversity
It was primary to transfer to the student the importance of his own responsibility on the project, transcending the usual condition of mere academic practice in the school. Their projects are already real actions to transform the reality from the
moment in which are the product of a responsible and critical thinking. To the regular development of the Subject of Architectural Projects with theoretical classes and collective corrections in Workshop of Projects, it was incorporated a
series of methodologies to activate the individual and collective learning.
The project critically acts on city model, proposes an architectural intervention with transformative will and the classroom becomes a social space where individual engagements and collective engagements are added. This dialectic with reality was concluded with the exhibition of projects, which the students explained to the neighbours as the end of the course, first in school and finally in their civic center.Fue primordial transferir al estudiante la importancia de su propia responsabilidad sobre el proyecto, trascendiendo la habitual condición de mera práctica escolar en la Escuela. Sus proyectos son ya verdaderas acciones para transformar la realidad desde el momento mismo en que son el producto de un pensamiento crítico y responsable. Al desarrollo habitual de la Asignatura de Proyectos Arquitectónicos con clases teóricas y correcciones colectivas en Taller de Proyectos se incorporan una serie de metodologías para activar individual y colectivamente el aprendizaje.
El proyecto actúa críticamente sobre el modelo de ciudad, propone una intervención arquitectónica con voluntad transformadora y el aula se convierte en un espacio social donde se suman compromisos individuales y compromisos
colectivos. Esta dialéctica con la realidad se concluyó con la exposición de los proyectos realizados, que los estudiantes explicaron ante los vecinos del barrio como final de curso, en la Escuela y en su Centro Cívico
On the Whitham hierarchy: dressing scheme, string equations and additional symmetrie
A new description of the universal Whitham hierarchy in terms of a
factorization problem in the Lie group of canonical transformations is
provided. This scheme allows us to give a natural description of dressing
transformations, string equations and additional symmetries for the Whitham
hierarchy. We show how to dress any given solution and prove that any solution
of the hierarchy may be undressed, and therefore comes from a factorization of
a canonical transformation. A particulary important function, related to the
-function, appears as a potential of the hierarchy. We introduce a class
of string equations which extends and contains previous classes of string
equations considered by Krichever and by Takasaki and Takebe. The scheme is
also applied for an convenient derivation of additional symmetries. Moreover,
new functional symmetries of the Zakharov extension of the Benney gas equations
are given and the action of additional symmetries over the potential in terms
of linear PDEs is characterized
Hodograph solutions of the dispersionless coupled KdV hierarchies, critical points and the Euler-Poisson-Darboux equation
It is shown that the hodograph solutions of the dispersionless coupled KdV
(dcKdV) hierarchies describe critical and degenerate critical points of a
scalar function which obeys the Euler-Poisson-Darboux equation. Singular
sectors of each dcKdV hierarchy are found to be described by solutions of
higher genus dcKdV hierarchies. Concrete solutions exhibiting shock type
singularities are presented.Comment: 19 page
Magic Numbers for the Photoelectron Anisotropy in Li-Doped Dimethyl Ether Clusters
Photoelectron velocity map imaging of Li(CHOCH) clusters (1
n 175) is used to search for magic numbers related to the
photoelectron anisotropy. Comparison with density functional calculations
reveals magic numbers at n=4, 5, and 6, resulting from the symmetric charge
distribution with high s-character of the highest occupied molecular orbital.
Since each of these three cluster sizes correspond to the completion of a first
coordination shell, they can be considered as 'isomeric motifs of the first
coordination shell'. Differences in the photoelectron anisotropy, the vertical
ionization energies and the enthalpies of vaporization between
Li(CHOCH) and Na(CHOCH) can be rationalized in terms of
differences in their solvation shells, atomic ionization energies,
polarizabilities, metal-oxygen bonds, ligand-ligand interactions, and by
cooperative effects
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