Nonthermal gamma-ray and X-ray flashes from shock breakout in gamma-ray bursts/supernovae

Thermal X-ray emission which is simultaneous with the prompt gamma-rays has been detected for the first time from a supernova connected with a gamma-ray burst (GRB), namely GRB060218/SN2006aj. It has been interpreted as arising from the breakout of a mildly relativistic, radiation-dominated shock from a dense stellar wind surrounding the progenitor star. There is also evidence for the presence of a mildly relativistic ejecta in GRB980425/SN1998bw, based on its X-ray and radio afterglow. Here we study the process of repeated bulk Compton scatterings of shock breakout thermal photons by the mildly relativistic ejecta. During the shock breakout process, a fraction of the thermal photons would be repeatedly scattered between the pre-shock material and the shocked material as well as the mildly relativistic ejecta and, as a result, the thermal photons get boosted to increasingly higher energies. This bulk motion Comptonization mechanism will produce nonthermal gamma-ray and X-ray flashes, which could account for the prompt gamma-ray burst emission in low-luminosity supernova-connected GRBs, such as GRB060218. A Monte Carlo code has been developed to simulate this repeated scattering process, which confirms that a significant fraction of the thermal photons get "accelerated" to form a nonthermal component, with a dominant luminosity. This interpretation for the prompt nonthermal emission of GRB060218 may imply that either the usual internal shock emission from highly relativistic jets in these low-luminosity GRBs is weak, or alternatively, that there are no highly relativistic jets in this peculiar class of bursts.Comment: Accepted for publication in ApJ; Introduction expanded, references added, conclusions unchanged; total 7 pages including 2 color figures and 1 tabl

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages

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

Feelings Sustaining Text: Aphorisms and Inspiration

There are genres of reflection, one of which is constituted by the aphorism. These reflections are an art of ponderance, of pensiveness. Philosophy is not necessarily the best example, nor is it identical with the genre of reflection as such; it has had a hard time breaking with its derivative moments, and its history is of a catalogue of dogmas as well as progressive critiques. In logic, one of philosophy’s products, the continuous or infinite form of knowledge is condensed into the axiom or principle or formula, which carries the appearance of a statement of fact. Contrary to the latter, yet similar in form, produced by this tradition of doubt and certainty, is the aphorism, a moment of reflection concentrated into a phrase. A study of aphorisms here includes the exploration of their techniques of writing as compared to other similar generic forms. Specifically, the aphorism is compared to the fragment as it has been taken up by German idealism, and to the quotation post-Descartes

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages

The numeral system of Proto-Niger-Congo: A step-by-step reconstruction

This book proposes the reconstruction of the Proto-Niger-Congo numeral system. The emphasis is placed on providing an exhaustive account of the distribution of forms by families, groups, and branches. The big data bases used for this purpose open prospects for both working with the distribution of words that do exist and with the distribution of gaps in postulated cognates.  The distribution of filled cells and gaps is a useful tool for reconstruction.Following an introduction in the first chapter, the second chapter of this book is devoted to the study of various uses of noun class markers in numeral terms. The third chapter deals with the alignment by analogy in numeral systems. Chapter 4 offers a step-by-step reconstruction of number systems of the proto-languages underlying each of the twelve major NC families, on the basis of the step-by-step-reconstruction of numerals within each family. Chapter 5 deals with the reconstruction of the Proto-Niger-Congo numeral system on the basis of the step-by-step-reconstructions offered in Chapter 4. Chapter 6 traces the history of the numerals of Proto-Niger-Congo, reconstructed in Chapter 5, in each individual family of languages