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All-Optical Control Of Nonlinear Self-Focusing In Plasmas Using Non-Resonantly Driven Plasma Wave, Serguei Y. Kalmykov, Bradley A. Shadwick, Michael C. Downer

Serge Youri Kalmykov

Excitation of plasma density perturbations by an initially bi-color laser pulse helps to control nonlinear refraction in the plasma and enables various types of laser self-guiding. In this report we consider a setup that not only makes possible the transport of laser energy over cm-long relatively dense plasmas (n_0 = 10^{18} cm^{−3}) but also transforms the pulse into the unique format inaccessible to the conventional amplification techniques (relativistically intense periodic trains of few-cycle spikes). This well focusable pulse train is a novel light source interesting for ultra-fast high-field science applications. The opposite case of suppression of nonlinear self-focusing and dynamical …

Electron Self-Injection Into An Evolving Plasma Bubble: The Way To A Dark Current Free Gev-Scale Laser Accelerator, Serguei Y. Kalmykov, Arnaud Beck, Sunghwan A. Yi, Vladimir N. Khudik, Bradley A. Shadwick, Erik Lefebvre, Michael C. Downer

Serge Youri Kalmykov

A time-varying electron density bubble created by the radiation pressure of a tightly focused petawatt laser pulse traps electrons of ambient rarefied plasma and accelerates them to a GeV energy over a few-cm distance. Expansion of the bubble caused by the shape variation of the self-guided pulse is the primary cause of electron self-injection in strongly rarefied plasmas (n_0 ~ 10^{17} cm^{−3}). Stabilization and contraction of the bubble extinguishes the injection. After the bubble stabilization, longitudinal non-uniformity of the accelerating gradient results in a rapid phase space rotation that produces a quasi-monoenergetic bunch well before the de-phasing limit. Combination of …

The Positive Solutions Of The Matukuma Equation And The Problem Of Finite Radius And Finite Mass, Jurgen Batt, Yi Li

Yi Li

This work is an extensive study of the 3 different types of positive solutions of the Matukuma equation 1r2(r2ϕ′)′=−rλ−2(1+r2)λ/2ϕp,p>1,λ>0 : the E-solutions (regular at r = 0), the M-solutions (singular at r = 0) and the F-solutions (whose existence begins away from r = 0). An essential tool is a transformation of the equation into a 2-dimensional asymptotically autonomous system, whose limit sets (by a theorem of H. R. Thieme) are the limit sets of Emden–Fowler systems, and serve as to characterizate the different solutions. The emphasis lies on the study of the M-solutions. …

A Non-Autonomous Second Order Boundary Value Problem On The Half-Line, Gregory S. Spradlin

Greg S. Spradlin Ph.D.

By variational arguments, the existence of a solution to a nonautonomous second-order boundary problem on the half-line is proven. The corresponding autonomous problem has no solution, revealing significant differences between the autonomous and the non-autonomous case.

A Short-Distance Integral-Balance Solution To A Strong Subdiffusion Equation: A Weak Power-Law Profile, Jordan Hristov

Jordan Hristov

The work presents an integral solution of the time-fractional subdiffusion through a preliminary defined profile with unknown coefficients and the concept of penetration layer well known from the heat diffusion The profile satisfies the boundary conditions imposed at the boundary of the boundary layer in a weak form that allows its coefficients to be expressed through the boundary layer depth as unique parameter describing the profile. The technique is demonstrated by a solution of a time fractional subdiffusion equation in rectilinear 1-D conditions.

Some Features Of The Concentration Oscillations In The Phenylacetylene Oxidative Carbonylation Reaction (In Russian), Sergey N. Gorodsky

Sergey N. Gorodsky

Some modes of concentration oscillations in the homogeneous system KI-PdI2-CO-O2-CH3OH are described in this paper.

Energetyka Niskoemisyjna, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

Multirelational Organization Of Large-Scale Social Networks In An Online World, Renaud Lambiotte

Renaud Lambiotte

The capacity to collect fingerprints of individuals in online media has revolutionized the way researchers explore human society. Social systems can be seen as a nonlinear superposition of a multitude of complex social networks, where nodes represent individuals and links capture a variety of different social relations. Much emphasis has been put on the network topology of social interactions, however, the multidimensional nature of these interactions has largely been ignored, mostly because of lack of data. Here, for the first time, we analyze a complete, multirelational, large social network of a society consisting of the 300,000 odd players of a …

Using Clustering For Modeling Monthly Salary Grade, R. W. Hndoosh

R. W. Hndoosh

Clustering is considered as one of the most scientifically developments which the scientists reached at in the field of recent knowledge and technologies to discover the cluster's group. The clustering concept was introduced firstly by Ronald in 1955. The clustering's fundamental notion is represented in dividing the data into clusters. This research aims to using clustering for actual data modeling for the monthly salary grade of the teaching staff for one of the Mosul University's College in 2009, by using HCM algorithm to these data. Matlab software is used to write down the proposed algorithm programs. Results proved the efficiency …

Optimal Control Of A Switched System In Microbial Fed-Batch Fermentation Process, Chongyang Liu, Zhaohua Gong, Enmin Feng

Chongyang Liu

The main control goal in fed-batch fermentation process is to get a high concentration of production. In this paper, by taking the feed rate of glycerol as the control function, a nonlinear switched system is proposed to formulate the fed-batch fermentation process of glycerol to 1,3-propanediol (1,3-PD). To maximize the concentration of 1,3-PD at the terminal time, an optimal switching control model subject to constraints of continuous state inequality and control function is presented. A computational approach is developed to seek the optimal solution in two aspects. On the one hand, the control parametrization enhancing transform together with the control …

Boundary Type Quadrature Formulas Over Axially Symmetric Regions, Tian-Xiao He

Tian-Xiao He

A boundary type quadrature formula (BTQF) is an approximate integration formula with all its of evaluation points lying on the Boundary of the integration domain. This type formulas are particularly useful for the cases when the values of the integrand functions and their derivatives inside the domain are not given or are not easily determined. In this paper, we will establish the BTQFs over sonic axially symmetric regions. We will discuss time following three questions in the construction of BTQFs: (i) What is the highest possible degree of algebraic precision of the BTQF if it exists? (ii) What is the …

Is The Curvature Of The Flagellum Involved In The Apparent Cooperativity Of The Dynein Arms Along The "9+2" Axoneme?, Christian Cibert, Andrei Ludu

Andrei Ludu

Heat-Balance Integral To Fractional (Half-Time) Heat Diffusion Sub-Model, Jordan Hristov

Jordan Hristov

The fractional (half-time) sub-model of the heat diffusion equation, known as Dirac-like evolution diffusion equation has been solved by the heat-balance integral method and a parabolic pro file with unspecified exponent. The fractional heat-balance integral method has been tested with two classic examples: fixed temperature and fixed flux at the boundary. The heat-balance technique allows easily the convolution integral of the fractional half-time derivative to be solved as a convolution of the time-independent approximating function. The fractional sub-model provides an artificial boundary condition at the boundary that closes the set of the equations required to express all parameters of the …

The 1905 Einstein Equation In A General Mathematical Analysis Model Of Quasars, Byron E. Bell

Byron E. Bell

Numerical Modelling Of A 10-Cm-Long Multi-Gev Laser Wakefield Accelerator Driven By A Self-Guided Petawatt Pulse, Serguei Y. Kalmykov, Sunghwan A. Yi, Arnaud Beck, Agustin F. Lifschitz, Xavier Davoine, Erik Lefebvre, Alexander Pukhov, Vladimir N. Khudik, Gennady Shvets, Steven A. Reed, Peng Dong, Xiaoming Wang, Dongsu Du, Stefan Bedacht, Rafal B. Zgadzaj, Watson Henderson, Aaron Bernstein, Gilliss Dyer, Mikael Martinez, Erhard Gaul, Todd Ditmire, Michael C. Downer

Serge Youri Kalmykov

Holographic Visualization Of Laser Wakefields, Peng Dong, Steven A. Reed, Sunghwan A. Yi, Serguei Y. Kalmykov, Zhengyan Y. Li, Gennady Shvets, Nicholas H. Matlis, Christopher Mcguffey, Stepan S. Bulanov, Vladimir Chvykov, Galina Kalintchenko, Karl Krushelnick, Anatoly Maksimchuk, Takeshi Matsuoka, Alexander G. R. Thomas, Victor Yanovsky, Michael C. Downer

Serge Youri Kalmykov

We report ‘snapshots’ of laser-generated plasma accelerator structures acquired by frequency domain holography (FDH) and frequency domain shadowgraphy (FDS), techniques for visualizing quasi-static objects propagating near the speed of light. FDH captures images of sinusoidal wakes in mm-length plasmas of density 1 < n_{e} < 5 x 10^{18} cm^{−3} from phase modulations they imprint on co-propagating probe pulses. Changes in the wake structure (such as the curvature of the wavefront), caused by the laser and plasma parameter variations from shot to shot, were observed. FDS visualizes lasergenerated electron density bubbles in mm-length plasmas of density n_{e} > 10^{19} cm^{−3} using amplitude modulations they imprint on co-propagating probe pulses. Variations in the spatio-temporal structure of bubbles are inferred from corresponding variations in the shape of ‘bullets’ of probe light trapped inside them and correlated with mono-energetic electron generation. Both FDH and FDS average over structural variations that occur during propagation through the plasma medium. We explore …

On Approximating Point Spread Distributions, Tamas Lengyel

Tamas Lengyel

We discuss some properties of the point spread distribution, defined as the distribution of the difference of two independent binomial random variables with the same parameter n in- cluding exact and approximate probabilities and related optimization issues. We use various approximation techniques for different distributions, special functions, and analytic, combi- natorial and symbolic methods, such as multi-summation techniques. We prove that in case of unequal success rates, if these rates change with their difference kept fix and small, and n is appropriately bounded, then the point spread distribution only slightly changes for small point differences. We also prove that for …

Medicen, Bahram Agheli

Bahram Agheli

No abstract provided.

Formation Of Optical Bullets In Laser-Driven Plasma Bubble Accelerators, Peng Dong, Steven A. Reed, Sunghwan A. Yi, Serguei Y. Kalmykov, Gennady Shvets, Michael C. Downer, Nicholas H. Matlis, Wim P. Leemans, Christopher Mcguffey, Stepan S. Bulanov, Vladimir Chvykov, Galina Kalintchenko, Karl Krushelnick, Anatoly Maksimchuk, Takeshi Matsuoka, Alexander G. R. Thomas, Victor Yanovsky

Serge Youri Kalmykov

Electron density bubbles—wake structures generated in plasma of density n_{e} ~ 10^{19} cm^{-3} by the light pressure of intense ultrashort laser pulses—are shown to reshape weak copropagating probe pulses into optical ‘‘bullets.’’ The bullets are reconstructed using frequency-domain interferometric techniques in order to visualize bubble formation. Bullets are confined in three dimensions to plasma-wavelength size, and exhibit higher intensity, broader spectrum and flatter temporal phase than surrounding probe light, evidence of their compression by the bubble. Bullets observed at 0.8 < n_{e} < 1.2 x 10^{19} cm^{-3} provide the first observation of bubble formation below the electron capture threshold. At higher n_{e}, bullets appear with high shot-to-shot stability together with relativistic electrons that vary widely in spectrum, and help relate bubble formation to fast electron generation.

Morphological Evolution Of Single-Crystal Ultrathin Solid Films, Mikhail Khenner

Mikhail Khenner

An introduction to mathematical modeling of ultrathin solid films and the role of such modeling in nanotechnologies: Educational/Research presentation for senior physics majors

Conference Proceedings 3rd International Scientific Conference On “Energy Systems With It” At Alvsjö Fair In Association With Energitinget March 16-17 2010, Dr. Erik Dahlquist, Dr. Jenny Palm

Dr. Erik Dahlquist

2010 “The Energiting” is performed for the 12th time. The International Scientific conference is arranged for the 3rd time. The organisers are Swedish Energy Agency, Mälardalen University and the Research School for Energy Systems with LiU, KTH, UU and CTH. The first topic will be “Energy systems” covering use of renewable energy sources, energy conversion and process efficiency improvement with new technologies, as well as societal aspects of the introduction of new technologies. The second topic is “Energy and IT”. This covers energy and load management, interaction between production, distribution and “consumption”, usage of data for decision support and control, …

Comments Submitted To The Us Patent Office On Enhancing The Quality Of Examination, Ron D. Katznelson

Ron D. Katznelson

No abstract provided.

On Simulating Univariate And Multivariate Burr Type Iii And Type Xii Distributions, Todd C. Headrick, Mohan D. Pant, Yanyan Sheng

Mohan Dev Pant

This paper describes a method for simulating univariate and multivariate Burr Type III and Type XII distributions with specified correlation matrices. The methodology is based on the derivation of the parametric forms of a pdf and cdf for this family of distributions. The paper shows how shape parameters can be computed for specified values of skew and kurtosis. It is also demonstrated how to compute percentage points and other measures of central tendency such as the mode, median, and trimmed mean. Examples are provided to demonstrate how this Burr family can be used in the context of distribution fitting using …

Computing Prime Harmonic Sums, Eric Bach, Dominic Klyve, Jonathan P. Sorenson

Jonathan P. Sorenson

We discuss a method for computing Σ �≤� 1/�, using time about �2/3 and space about �1/3. It is based on the Meissel-Lehmer algorithm for computing the prime-counting function �(�), which was adapted and improved by Lagarias, Miller, and Odlyzko. We used this algorithm to determine the first point at which the prime harmonic sum first crosses.

Computing Prime Harmonic Sums, Eric Bach, Dominic Klyve, Jonathan P. Sorenson

Jonathan P. Sorenson

We discuss a method for computing Σ �≤� 1/�, using time about �2/3 and space about �1/3. It is based on the Meissel-Lehmer algorithm for computing the prime-counting function �(�), which was adapted and improved by Lagarias, Miller, and Odlyzko. We used this algorithm to determine the first point at which the prime harmonic sum first crosses.

Time Is Not A Vector: Corrections To The Article “Vectorial Relativity Versus Special Or General Relativity?”, Jorge A. Franco

Jorge A Franco

In this work the main conceptual errors that sequentially were introduced in the development of the Special Theory of Relativity (SR) are explained. A simple presentation of the Lorentz Transformations (LT) is given, within where it is emphasized that, by using an incomplete configuration, repeated by more than one hundred years, it leads to a first error of a chain of them, when it is assumed that the cross sectional components, in the movable inertial reference system, are invariant or not affected by its relative movement respect a fixed inertial system, on the basis of a presumed “postulate of isotropy“ …

Modular Exponentiation Via The Explicit Chinese Remainder Theorem, Daniel J. Bernstein, Jonathan P. Sorenson

Jonathan P. Sorenson

In this paper we consider the problem of computing xe mod m for large integers x, e, and m. This is the bottleneck in Rabin’s algorithm for testing primality, the Diffie-Hellman algorithm for exchanging cryptographic keys, and many other common algorithms.

Modular Exponentiation Via The Explicit Chinese Remainder Theorem, Daniel J. Bernstein, Jonathan P. Sorenson

Jonathan P. Sorenson

In this paper we consider the problem of computing xe mod m for large integers x, e, and m. This is the bottleneck in Rabin’s algorithm for testing primality, the Diffie-Hellman algorithm for exchanging cryptographic keys, and many other common algorithms.

Selective Recursive Kernel Learning For Online Identification Of Nonlinear Systems With Narx Form, Yi Liu, Haiqing Wang, Jiang Yu, Ping Li

Dr. Yi Liu

Online identification of nonlinear systems is still an important while difficult task in practice. A general and simple online identification method, namely Selective Recursive Kernel Learning (SRKL), is proposed for multi-input–multi-output (MIMO) systems with the nonlinear autoregressive with exogenous input form. A two-stage RKL online identification framework is first formulated, where the information contained by a sample (i.e., the new arriving or old useless one) can be introduced into and/or deleted from the model, recursively. Then, a sparsification strategy to restrict the model complexity is developed to guarantee all the output channels of the MIMO model accurate simultaneously. Specially, a …

Improved Automated Monitoring And New Analysis Algorithm For Circadean Phototaxis Rhythms In Chlamydomonas, Christa Gaskill, Jennifer Forbes-Stovall, Bruce Kessler, Mike Young, Claire A. Rinehart, Sigrid Jacobshagen

Bruce Kessler

Automated monitoring of circadian rhythms is an efficient way of gaining insight into oscillation parameters like period and phase for the underlying pacemaker of the circadian clock. Measurement of the circadian rhythm of phototaxis (swimming towards light) exhibited by the green alga Chlamydomonas reinhardtii has been automated by directing a narrow and dim light beam through a culture at regular intervals and determining the decrease in light transmittance due to the accumulation of cells in the beam. In this study, the monitoring process was optimized by constructing a new computercontrolled measuring machine that limits the test beam to wavelengths reported …