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Workload modeling for computer systems performance evaluation
http://cds.cern.ch/record/2005898
Reliable performance evaluations require the use of representative workloads. This is no easy task since modern computer systems and their workloads are complex, with many interrelated attributes and complicated structures. Experts often use sophisticated mathematics to analyze and describe workload models, making these models difficult for practitioners to grasp. This book aims to close this gap by emphasizing the intuition and the reasoning behind the definitions and derivations related to the workload models. It provides numerous examples from real production systems, with hundreds of graphs. Using this book, readers will be able to analyze collected workload data and clean it if necessary, derive statistical models that include skewed marginal distributions and correlations, and consider the need for generative models and feedback from the system. The descriptive statistics techniques covered are also useful for other domains.Feitelson, Dror GWed, 01 Apr 2015 16:15:16 GMThttp://cds.cern.ch/record/2005898Black holes thermodynamics, information, and firewalls
http://cds.cern.ch/record/2005897
This book reflects the resurgence of interest in the quantum properties of black holes, culminating most recently in controversial discussions about firewalls. On the thermodynamic side, it describes how new developments allowed the inclusion of pressure/volume terms in the first law, leading to a new understanding of black holes as chemical systems, experiencing novel phenomena such as triple points and reentrant phase transitions. On the quantum-information side, the reader learns how basic arguments undergirding quantum complementarity have been shown to be flawed; and how this suggests that a black hole may surround itself with a firewall: a violent and chaotic region of highly excited states. In this thorough and pedagogical treatment, Robert Mann traces these new developments from their roots to our present-day understanding, highlighting their relationships and the challenges they present for quantum gravity.Mann, Robert BWed, 01 Apr 2015 16:02:13 GMThttp://cds.cern.ch/record/2005897Electrodynamics: the field-free approach : electrostatics, magnetism, induction, relativity and field theory
http://cds.cern.ch/record/2005896
This book is intended as an undergraduate textbook in electrodynamics at basic or advanced level. The objective is to attain a general understanding of the electrodynamic theory and its basic experiments and phenomena in order to form a foundation for further studies in the engineering sciences as well as in modern quantum physics. The outline of the book is obtained from the following principles: • Base the theory on the concept of force and mutual interaction • Connect the theory to experiments and observations accessible to the student • Treat the electric, magnetic and inductive phenomena cohesively with respect to force, energy, dipoles and material • Present electrodynamics using the same principles as in the preceding mechanics course • Aim at explaining that theory of relativity is based on the magnetic effect • Introduce field theory after the basic phenomena have been explored in terms of force Although electrodynamics is described in this book from its 1st principles, prior knowledge of about one semester of university studies in mathematics and physics is required, including vector algebra, integral and differential calculus as well as a course in mechanics, treating Newton’s laws and the energy principle. The target groups are physics and engineering students, as well as professionals in the field, such as high school teachers and employees in the telecom industry. Chemistry and computer science students may also benefit from the book.Prytz, KjellWed, 01 Apr 2015 16:02:13 GMThttp://cds.cern.ch/record/2005896Simulation of optical soliton control in micro- and nanoring resonator systems
http://cds.cern.ch/record/2005895
This book introduces optical soliton control in micro- and nanoring resonator systems. It describes how the ring resonator systems can be optimized as optical tweezers for photodetection by controlling the input power, ring radii and coupling coefficients of the systems. Numerous arrangements and configurations of micro and nanoring resonator systems are explained. The analytical formulation and optical transfer function for each model and the interaction of the optical signals in the systems are discussed. This book shows that the models designed are able to control the dynamical behaviour of generated signals.Daud, SuzairiIdrus, Sevia MahdalizaAli, JalilWed, 01 Apr 2015 16:02:03 GMThttp://cds.cern.ch/record/2005895Neutrino oscillations: a practical guide to basics and applications
http://cds.cern.ch/record/2005894
Neutrino oscillation (N.O.) is the only firm evidence of the physics beyond the Standard Model of particle physics and is one of the hottest topics in elementary particle physics today. This book focuses on the N.O., from its history to the future prospects, from the basic theories to the experiments. Various phenomena of N.O. are described intuitively with thorough explanations of the fundamental physics behind well-known formulations. For example, while many textbooks start with a discussion of the mixing matrix, this book stresses that N.O. is caused by the transition amplitudes between different neutrino flavors, and that the purpose of N.O. experiments is to measure transition amplitudes and think of its origin. The current understanding of neutrino oscillation is also summarized using the most up-to-date measurements, including the recently measured neutrino mixing angle θ13, and the future prospects of N.O. studies are described as well. The level of this book makes it a bridge between introductory textbooks and scientific papers.Suekane, FumihikoWed, 01 Apr 2015 16:01:58 GMThttp://cds.cern.ch/record/2005894Return to the far side of planet Moore!: rambling through observations, friendships and antics of sir Patrick Moore
http://cds.cern.ch/record/2005893
The result of an exhaustive study of Sir Patrick Moore’s observations of the Moon and planets for more than 60 years, this book is a fantastic companion to the extremely popular, “It Came From Outer Space Wearing an RAF Blazer!” written by the same author. Moore recorded his telescopic observations in his logbooks, which are reproduced and described here in detail, along with his sketches and notes. In this light, the author discusses the factors that caused Moore to switch from lunar observing to planetary and variable star observing. He has also included personal recollections and humorous anecdotes from Moore’s friends and acquaintances, as well as a look at his best loved books. Further chapters describe Moore’s foreign travels and correspondence with those back home. Lastly, the author has not neglected a few of Moore’s most memorable television and radio appearances, which are examined along with a close up of what it was like to visit Moore’s beloved home of Farthings in Selsey. Essentially, this is a book written by popular demand from the readers of the author’s original biography, who craved more of Moore!Mobberley, MartinWed, 01 Apr 2015 16:01:58 GMThttp://cds.cern.ch/record/2005893Multidimensional periodic Schrödinger operator: perturbation theory and applications
http://cds.cern.ch/record/2005892
The book describes the direct problems and the inverse problem of the multidimensional Schrödinger operator with a periodic potential. This concerns perturbation theory and constructive determination of the spectral invariants and finding the periodic potential from the given Bloch eigenvalues. The unique method of this book derives the asymptotic formulas for Bloch eigenvalues and Bloch functions for arbitrary dimension. Moreover, the measure of the iso-energetic surfaces in the high energy region is construct and estimated. It implies the validity of the Bethe-Sommerfeld conjecture for arbitrary dimensions and arbitrary lattices. Using the perturbation theory constructed in this book, the spectral invariants of the multidimensional operator from the given Bloch eigenvalues are determined. Some of these invariants are explicitly expressed by the Fourier coefficients of the potential. This way the possibility to determine the potential constructively by using Bloch eigenvalues as input data is given. In the end an algorithm for the unique determination of the potential is given.Veliev, OktayWed, 01 Apr 2015 16:01:54 GMThttp://cds.cern.ch/record/2005892Introduction to quantum metrology: quantum standards and instrumentation
http://cds.cern.ch/record/2005891
This book presents the theory of quantum effects used in metrology and results of the author’s own research in the field of quantum electronics. The book provides also quantum measurement standards used in many branches of metrology for electrical quantities, mass, length, time and frequency. This book represents the first comprehensive survey of quantum metrology problems. As a scientific survey, it propagates a new approach to metrology with more emphasis on its connection with physics. This is of importance for the constantly developing technologies and nanotechnologies in particular. Providing a presentation of practical applications of the effects used in quantum metrology for the construction of quantum standards and sensitive electronic components, the book is useful for a wide audience of physicists and metrologists in the broad sense of both terms. In 2014 a new system of units, the so called Quantum SI, is introduced. This book helps to understand and approve the new system to both technology and academic community.Nawrocki, WaldemarWed, 01 Apr 2015 16:01:54 GMThttp://cds.cern.ch/record/2005891Synchronization of integral and fractional order chaotic systems: a differential algebraic and differential geometric approach with selected applications in real-time
http://cds.cern.ch/record/2005890
This book provides a general overview of several concepts of synchronization and brings together related approaches to secure communication in chaotic systems. This is achieved using a combination of analytic, algebraic, geometrical and asymptotical methods to tackle the dynamical feedback stabilization problem. In particular, differential-geometric and algebraic differential concepts reveal important structural properties of chaotic systems and serve as guide for the construction of design procedures for a wide variety of chaotic systems. The basic differential algebraic and geometric concepts are presented in the first few chapters in a novel way as design tools, together with selected experimental studies demonstrating their importance. The subsequent chapters treat recent applications. Written for graduate students in applied physical sciences, systems engineers, and applied mathematicians interested in synchronization of chaotic systems and in secure communications, this self-contained text requires only basic knowledge of integer ordinary and fractional ordinary differential equations. Design applications are illustrated with the help of several physical models of practical interest.Martínez-Guerra, RafaelPérez-Pinacho, Claudia AGómez-Cortés, Gian CarloWed, 01 Apr 2015 16:01:53 GMThttp://cds.cern.ch/record/2005890Introduction to soft-collinear effective theory
http://cds.cern.ch/record/2005889
Among resummation techniques for perturbative QCD in the context of collider and flavor physics, soft-collinear effective theory (SCET) has emerged as both a powerful and versatile tool, having been applied to a large variety of processes, from B-meson decays to jet production at the LHC. This book provides a concise, pedagogical introduction to this technique. It discusses the expansion of Feynman diagrams around the high-energy limit, followed by the explicit construction of the effective Lagrangian - first for a scalar theory, then for QCD. The underlying concepts are illustrated with the quark vector form factor at large momentum transfer, and the formalism is applied to compute soft-gluon resummation and to perform transverse-momentum resummation for the Drell-Yan process utilizing renormalization group evolution in SCET. Finally, the infrared structure of n-point gauge-theory amplitudes is analyzed by relating them to effective-theory operators. This text is suitable for graduate students and non-specialist researchers alike as it requires only basic knowledge of perturbative QCD.Becher, ThomasBroggio, AlessandroFerroglia, AndreaWed, 01 Apr 2015 16:01:53 GMThttp://cds.cern.ch/record/2005889Survival and sacrifice in Mars exploration: what we know from polar expeditions
http://cds.cern.ch/record/2005888
With current technology, a voyage to Mars and back will take three years. That’s a lot of time for things to go wrong. But sooner or later a commercial enterprise will commit itself to sending humans to Mars. How will the astronauts survive? Some things to consider are: ith current technology, a voyage to Mars and back will take three years. That’s a lot of time for things to go wrong. But sooner or later a commercial enterprise will commit itself to sending humans to Mars. How will the astronauts survive? Some things to consider are: • Who decides what medical resources are used for whom? Who decides what medical resources are used for whom? • What is the relative weight of mission success and the health of the crew? What is the relative weight of mission success and the health of the crew? • Do we allow crewmembers to sacrifi ce their lives for the good of the mission? Do we allow crewmembers to sacrifi ce their lives for the good of the mission? • And what if a crewmember does perish? Do we store the body for return to Earth or give the member a burial in space? Questions like these, and hundreds of others, have been explored by science fi ction, but scant attention has been paid by those designing missions. Fortunately, the experience gained in polar exploration more than 100 years ago provides crews and mission planners with a framework to deal with contingencies and it is this that forms the core of this book. Why the parallels between polar and space exploration? Because polar exploration offers a better analogy for a Mars mission today than those invoked by the space community. Although astronauts are routinely compared to Lewis and Clark, Mars-bound astronauts will be closer in their roles to polar explorers. And, as much as space has been described as a New Frontier, Mars bears greater similarity to the polar regions, which is why so much can be learned from those who ventured there. And what if a crewmember does perish? Do we store the body forreturn to Earth or give the member a burial in space? Questions like these, and hundreds of others, have been explored by science fi ction, but scant attention has been paid by those designing missions. Fortunately, the experience gained in polar exploration more than 100 years ago provides crews and mission planners with a framework to deal with contingencies and it is this that forms the core of this book. Why the parallels between polar and space exploration? Because polar exploration offers a better analogy for a Mars mission today than those invoked by the space community. Although astronauts are routinely compared to Lewis and Clark, Mars-bound astronauts will be closer in their roles to polar explorers. And, as much as space has been described as a New Frontier, Mars bears greater similarity to the polar regions, which is why so much can be learned from those who ventured there.Seedhouse, ErikWed, 01 Apr 2015 16:01:53 GMThttp://cds.cern.ch/record/2005888Mercury's interior, surface, and surrounding environment: latest discoveries
http://cds.cern.ch/record/2005887
This SpringerBrief details the MESSENGER Mission, the findings of which present challenges to widely held conventional views and remaining mysteries surrounding the planet. The work answers the question of why Mercury is so dense, and the implications from geochemical data on its planetary formation. It summarizes imaging and compositional data from the terrestrial planet surface processes and explains the geologic history of Mercury. It also discusses the lack of southern hemisphere coverage. Our understanding of the planet Mercury has been in a transitional phase over the decades since Mariner 10. The influx of new data from the NASA MESSENGER Mission since it was inserted into the orbit of Mercury in March of 2011 has greatly accelerated that shift. The combined compositional data of relatively high volatiles (S, K), relatively low refractories (Al, Ca), and low crustal iron, combined with an active, partially molten iron rich core, has major implications for Mercury and Solar System formation. From a scientist at NASA Goddard Space Flight Center, this presents a comprehensive overview of the discoveries from the ten-year MESSENGER mission.Clark, Pamela ElizabethWed, 01 Apr 2015 16:01:53 GMThttp://cds.cern.ch/record/2005887Dynamic scenarios in two-state quantum dot lasers: excited state lasing, ground state quenching, and dual-mode operation
http://cds.cern.ch/record/2005886
André Röhm investigates the dynamic properties of two-state lasing quantum dot lasers, with a focus on ground state quenching. With a novel semi-analytical approach, different quenching mechanisms are discussed in an unified framework and verified with numerical simulations. The known results and experimental findings are reproduced and parameter dependencies are systematically studied. Additionally, the turn-on dynamics and modulation response curves of two-state lasing devices are presented. Contents Quantum Dot Laser Theory Two-State Lasing and Ground-State Quenching Modulation Response Target Groups Researchers and students in the field of theoretical physics Practitioners in this area The Author André Röhm wrote his master’s thesis under the supervision of Prof. Dr. Eckehard Schöll, PhD and Prof. Dr. Kathy Lüdge in the Collaborative Research Center SFB 910 at the Institute of Theoretical Physics at TU Berlin.Röhm, AndréWed, 01 Apr 2015 16:01:49 GMThttp://cds.cern.ch/record/2005886Stochastic non-excitable systems with time delay: modulation of noise effects by time-delayed feedback
http://cds.cern.ch/record/2005885
Paul M. Geffert analyses the interplay of noise and time delay in non-excitable nonlinear systems and the modulation of stochastic effects. In particular, the author studies coherence resonance, which is a constructive effect of noise that occurs in nonlinear systems, and demonstrates that it can be modulated by time-delayed feedback. Analytical methods for the investigation of stochastic delay differential equations are developed. Noise or random perturbations and time delay are two phenomena which arise in many fields of physics, chemistry, or biology, just to mention a few examples. The investigated model is a generic Hopf normal form so that these methods and results can be transferred to many different areas of science. Contents Stochastic Effects in Nonlinear Systems Coherence Resonance Time-Delayed Feedback in Nonlinear Stochastic Systems Coupled Stochastic Systems Target Groups Researchers and students in the field of nonlinear dynamics, stochastic processes and stochastic delay differential equations Practitioners in these areas The Author Paul M. Geffert wrote his master’s thesis under the supervision of Prof. Dr. Eckehard Schöll, PhD in the Collaborative Research Center SFB 910 at the Institute of Theoretical Physics at TU Berlin. In 2015 he will start his PhD studies at Queen Mary University of London.Geffert, Paul MWed, 01 Apr 2015 16:01:49 GMThttp://cds.cern.ch/record/2005885Dissipative exciton dynamics in light-harvesting complexes
http://cds.cern.ch/record/2005884
Marco Schröter investigates the influence of the local environment on the exciton dynamics within molecular aggregates, which build, e.g., the light-harvesting complexes of plants, bacteria or algae by means of the hierarchy equations of motion (HEOM) method. He addresses the following questions in detail: How can coherent oscillations within a system of coupled molecules be interpreted? What are the changes in the quantum dynamics of the system for increasing coupling strength between electronic and nuclear degrees of freedom? To what extent does decoherence govern the energy transfer properties of molecular aggregates?.Schröter, MarcoWed, 01 Apr 2015 16:01:49 GMThttp://cds.cern.ch/record/2005884NOMA 2013 International Workshop
http://cds.cern.ch/record/2005883
In the field of Dynamical Systems, nonlinear iterative processes play an important role. Nonlinear mappings can be found as immediate models for many systems from different scientific areas, such as engineering, economics, biology, or can also be obtained via numerical methods permitting to solve non-linear differential equations. In both cases, the understanding of specific dynamical behaviors and phenomena is of the greatest interest for scientists. This volume contains papers that were presented at the International Workshop on Nonlinear Maps and their Applications (NOMA 2013) held in Zaragoza, Spain, on September 3-4, 2013. This kind of collaborative effort is of paramount importance in promoting communication among the various groups that work in dynamical systems and networks in their research theoretical studies as well as for applications. This volume is suitable for graduate students as well as researchers in the field.López-Ruiz, RicardoFournier-Prunaret, DanièleNishio, YoshifumiGrácio, ClaraWed, 01 Apr 2015 16:01:43 GMThttp://cds.cern.ch/record/2005883Colloquium De Giorgi 2013 and 2014
http://cds.cern.ch/record/2005882
Since 2001 the Scuola Normale Superiore di Pisa has organized the "Colloquio De Giorgi", a series of colloquium talks named after Ennio De Giorgi. The Colloquio is addressed to a general mathematical audience, and especially meant to attract graduate students and advanced undergraduate students. The lectures are intended to be not too technical, in fields of wide interest. They must provide an overview of the general topic, possibly in a historical perspective, together with a description of more recent progress. The idea of collecting the materials from these lectures and publishing them in annual volumes came out recently, as a recognition of their intrinsic mathematical interest, and also with the aim of preserving memory of these events.Zannier, UmbertoWed, 01 Apr 2015 16:01:39 GMThttp://cds.cern.ch/record/2005882International Conference on Applied Mathematics and Informatics
http://cds.cern.ch/record/2005881
This book highlights recent compelling research results and trends in various aspects of contemporary mathematics, emphasizing applications to real-world situations. The chapters present exciting new findings and developments in situations where mathematical rigor is combined with common sense. A multi-disciplinary approach, both within each chapter and in the volume as a whole, leads to practical insights that may result in a more synthetic understanding of specific global issues—as well as their possible solutions. The volume will be of interest not only to experts in mathematics, but also to graduate students, scientists, and practitioners from other fields including physics, biology, geology, management, and medicine.Tost, GerardVasilieva, OlgaWed, 01 Apr 2015 16:01:39 GMThttp://cds.cern.ch/record/2005881Birational geometry of foliations
http://cds.cern.ch/record/2005880
The text presents the birational classification of holomorphic foliations of surfaces. It discusses at length the theory developed by L.G. Mendes, M. McQuillan and the author to study foliations of surfaces in the spirit of the classification of complex algebraic surfaces.Brunella, MarcoWed, 01 Apr 2015 16:01:33 GMThttp://cds.cern.ch/record/2005880Evolution PDEs with nonstandard growth conditions: existence, uniqueness, localization, blow-up
http://cds.cern.ch/record/2005879
This monograph offers the reader a treatment of the theory of evolution PDEs with nonstandard growth conditions. This class includes parabolic and hyperbolic equations with variable or anisotropic nonlinear structure. We develop methods for the study of such equations and present a detailed account of recent results. An overview of other approaches to the study of PDEs of this kind is provided. The presentation is focused on the issues of existence and uniqueness of solutions in appropriate function spaces, and on the study of the specific qualitative properties of solutions, such as localization in space and time, extinction in a finite time and blow-up, or nonexistence of global in time solutions. Special attention is paid to the study of the properties intrinsic to solutions of equations with nonstandard growth.Antontsev, StanislavShmarev, SergeyWed, 01 Apr 2015 16:01:28 GMThttp://cds.cern.ch/record/2005879Selected applications of convex optimization
http://cds.cern.ch/record/2005878
This book focuses on the applications of convex optimization and highlights several topics, including support vector machines, parameter estimation, norm approximation and regularization, semi-definite programming problems, convex relaxation, and geometric problems. All derivation processes are presented in detail to aid in comprehension. The book offers concrete guidance, helping readers recognize and formulate convex optimization problems they might encounter in practice.Li, LiWed, 01 Apr 2015 16:01:28 GMThttp://cds.cern.ch/record/2005878Mathematical modelling and numerical simulation of oil pollution problems
http://cds.cern.ch/record/2005877
Written by outstanding experts in the fields of marine engineering, atmospheric physics and chemistry, fluid dynamics and applied mathematics, the contributions in this book cover a wide range of subjects, from pure mathematics to real-world applications in the oil spill engineering business. Offering a truly interdisciplinary approach, the authors present both mathematical models and state-of-the-art numerical methods for adequately solving the partial differential equations involved, as well as highly practical experiments involving actual cases of ocean oil pollution. It is indispensable that different disciplines of mathematics, like analysis and numerics, together with physics, biology, fluid dynamics, environmental engineering and marine science, join forces to solve today’s oil pollution problems. The book will be of great interest to researchers and graduate students in the environmental sciences, mathematics and physics, showing the broad range of techniques needed in order to solve these pollution problems; and to practitioners working in the oil spill pollution industry, offering them a professional reference resource.Ehrhardt, MatthiasWed, 01 Apr 2015 16:01:28 GMThttp://cds.cern.ch/record/2005877Advances in variational and hemivariational inequalities: theory, numerical analysis, and applications
http://cds.cern.ch/record/2005876
Highlighting recent advances in variational and hemivariational inequalities with an emphasis on theory, numerical analysis and applications, this volume serves as an indispensable resource to graduate students and researchers interested in the latest results from recognized scholars in this relatively young and rapidly-growing field. Particularly, readers will find that the volume’s results and analysis present valuable insights into the fields of pure and applied mathematics, as well as civil, aeronautical, and mechanical engineering. Researchers and students will find new results on well posedness to stationary and evolutionary inequalities and their rigorous proofs. In addition to results on modeling and abstract problems, the book contains new results on the numerical methods for variational and hemivariational inequalities. Finally, the applications presented illustrate the use of these results in the study of miscellaneous mathematical models which describe the contact between deformable bodies and a foundation. This includes the modelling, the variational and the numerical analysis of the corresponding contact processes. Furthermore, it can be used as supplementary reading material for advanced specialized courses in mathematical modeling for students with a strong background knowledge on nonlinear analysis, numerical analysis, partial differential equations, and mechanics of continua.Han, WeiminMigórski, StanisławSofonea, MirceaWed, 01 Apr 2015 16:01:28 GMThttp://cds.cern.ch/record/2005876The nonlinear Schrödinger equation: singular solutions and optical collapse
http://cds.cern.ch/record/2005875
This book is an interdisciplinary introduction to optical collapse of laser beams, which is modelled by singular (blow-up) solutions of the nonlinear Schrödinger equation. With great care and detail, it develops the subject including the mathematical and physical background and the history of the subject. It combines rigorous analysis, asymptotic analysis, informal arguments, numerical simulations, physical modelling, and physical experiments. It repeatedly emphasizes the relations between these approaches, and the intuition behind the results. The Nonlinear Schrödinger Equation will be useful to graduate students and researchers in applied mathematics who are interested in singular solutions of partial differential equations, nonlinear optics and nonlinear waves, and to graduate students and researchers in physics and engineering who are interested in nonlinear optics and Bose-Einstein condensates. It can be used for courses on partial differential equations, nonlinear waves, and nonlinear optics. Gadi Fibich is a Professor of Applied Mathematics at Tel Aviv University. “This book provides a clear presentation of the nonlinear Schrodinger equation and its applications from various perspectives (rigorous analysis, informal analysis, and physics). It will be extremely useful for students and researchers who enter this field.” Frank Merle, Université de Cergy-Pontoise and Institut des Hautes Études Scientifiques, FranceFibich, GadiWed, 01 Apr 2015 16:01:23 GMThttp://cds.cern.ch/record/2005875Analysis and enumeration: algorithms for biological graphs
http://cds.cern.ch/record/2005874
In this work we plan to revise the main techniques for enumeration algorithms and to show four examples of enumeration algorithms that can be applied to efficiently deal with some biological problems modelled by using biological networks: enumerating central and peripheral nodes of a network, enumerating stories, enumerating paths or cycles, and enumerating bubbles. Notice that the corresponding computational problems we define are of more general interest and our results hold in the case of arbitrary graphs. Enumerating all the most and less central vertices in a network according to their eccentricity is an example of an enumeration problem whose solutions are polynomial and can be listed in polynomial time, very often in linear or almost linear time in practice. Enumerating stories, i.e. all maximal directed acyclic subgraphs of a graph G whose sources and targets belong to a predefined subset of the vertices, is on the other hand an example of an enumeration problem with an exponential number of solutions, that can be solved by using a non trivial brute-force approach. Given a metabolic network, each individual story should explain how some interesting metabolites are derived from some others through a chain of reactions, by keeping all alternative pathways between sources and targets. Enumerating cycles or paths in an undirected graph, such as a protein-protein interaction undirected network, is an example of an enumeration problem in which all the solutions can be listed through an optimal algorithm, i.e. the time required to list all the solutions is dominated by the time to read the graph plus the time required to print all of them. By extending this result to directed graphs, it would be possible to deal more efficiently with feedback loops and signed paths analysis in signed or interaction directed graphs, such as gene regulatory networks. Finally, enumerating mouths or bubbles with a source s in a directed graph, that is enumerating all the two vertex-disjoint directed paths between the source s and all the possible targets, is an example of an enumeration problem in which all the solutions can be listed through a linear delay algorithm, meaning that the delay between any two consecutive solutions is linear, by turning the problem into a constrained cycle enumeration problem. Such patterns, in a de Bruijn graph representation of the reads obtained by sequencing, are related to polymorphisms in DNA- or RNA-seq data.Marino, AndreaWed, 01 Apr 2015 16:01:15 GMThttp://cds.cern.ch/record/2005874