Avoiding BGP Security Holes by MPLS

1 Introduction A router running BGP can communicate with its neighbors, essentially telling them to which networks the router can efficiently send data.However, a misconfig- ured router, or one that has been compromised by an on- line intruder, can cause chaos by advertising itself as the best path to an unrelated network. That' s because routers using BGP implicitly trust their neighbors on the Internet- - they don' t ask for any sort of digital identi- fication. Using such digital forgery…     

POETIC: Interactive solutions to alleviate the reversal error in student–professor type problems

The reversal error—reversing the relationship between two variables in a mathematical word problem—is a long-standing issue in mathematics education, despite its apparent simplicity. In this paper, we describe and study POETIC, an interactive web-based environment we developed to teach users to avoid the reversal error. POETIC uses two types of novel interactive visualization, called the Test-Case and Room-Metaphor approaches. To verify the effectiveness of these approaches, we conducted crowdsourcing-based comparison studies with 200 participants and found that both approaches significantly decreased the frequency of reversal errors for certain types of word problems. Our results show that interactive visualization of equations can reduce the occurrence of the reversal error.     

A generalized Suzuki–Trotter type method in optimal control of coupled Schrödinger equations

A generalized Suzuki–Trotter (GST) method for the solution of an optimal control problem for quantum molecular systems is presented in this work. The control of such systems gives rise to a minimization problem with constraints given by a system of coupled Schrödinger equations. The computational bottleneck of the corresponding minimization methods is the solution of time-dependent Schrödinger equations. To solve the Schrödinger equations we use the GST framework to obtain an explicit polynomial approximation of the matrix exponential function. The GST method almost exclusively uses the action of the Hamiltonian and is therefore efficient and easy to implement for a variety of quantum systems. Following a first discretize, then optimize approach we derive the correct discrete representation of the gradient and the Hessian. The derivatives can naturally be expressed in the GST framework and can therefore be efficiently computed. By recomputing the solutions of the Schrödinger equations instead of saving the whole time evolution, we are able to significantly reduce the memory requirements of the method at the cost of additional computations. This makes first and second order optimization methods viable for large scale problems. In numerical experiments we compare the performance of different first and second order optimization methods using the GST method. We observe fast local convergence of second order methods.     

Orthonormal Bernoulli polynomials for space–time fractal-fractional modified Benjamin–Bona–Mahony type equations

Engineering with Computers - In this study, a new fractal-fractional (FF) derivative is defined by coupling the local conformable derivative and non-local Caputo fractional derivative. Using the...     

Backward difference formulae for Kuramoto–Sivashinsky type equations

We analyze the discretization of the periodic initial value problem for Kuramoto–Sivashinsky type equations with Burgers nonlinearity by implicit–explicit backward difference formula (BDF) methods, establish stability and derive optimal order error estimates. We also study discretization in space by spectral methods.     

Some generalized Ostrowski–Grüss type integral inequalities

In this paper, we establish some new Ostrowski–Grüss type integral inequalities involving $(k?1)$ interior points in 1D case, which are generalizations of some known results in the literature, and one of which is sharp. Then we deduce an Ostrowski–Grüss type integral inequality in 2D case involving ${(k?1)}^2$ interior points for the first time. We also present one application on the estimate of error bound for numerical integration formula, in which a sharp error bound for a new numerical integration formula is provided by the results established.     

On pseudo-fractional integral inequalities related to Hermite–Hadamard type

General versions of Hermite–Hadamard type inequality for pseudo-fractional integrals of the order \(\alpha >0\) on a semiring \(\left( \left[ a,b\right] ,\oplus ,\odot \right) \) are studied. These inequalities include both pseudo-integral and fractional integral. The well-known previous results are shown to be special cases of our results. Finally, two open problems for further investigations are given.     

Laguerre wavelet method for solving Thomas–Fermi type equations

Engineering with Computers - An efficient numerical algorithm based on the Laguerre wavelets collocation technique for numerical solutions of a class of Thomas–Fermi boundary value problems,...     

Exact inflation in Einstein–Gauss–Bonnet gravity

We study cosmological inflation in the Einstein gravity model with the additionally included Gauss–Bonnet term nonminimally coupled to a scalar field. We prove that inflationary solutions of exponential and power-law types are allowable, and we found few examples of them. We also propose a method for construction of exact inflationary solutions for a single scalar field with a given scale factor and Gauss–Bonnet coupling term in a spatially flat Friedmann–Robertson–Walker Universe on the basis of connection with standard inflation and using special assumptions. With one special anzatz we presented the set of equations in a form that allows for generation of exact solutions (at least in quadratures) of a wide class by setting the scale factor.     

Fouling detection in a heat exchanger by observer of Takagi–Sugeno type for systems with unknown polynomial inputs

This paper proposes a new method for fouling detection in a heat exchanger. It is based on the modeling of the system in a fuzzy Takagi–Sugeno representation derived from a physical model. With this representation, the design of a fuzzy observer with unknown inputs of polynomial types is obtained via a LMI formulation. Main advantages of the proposed method are that neither specific sensor, excepted standard ones, nor special operating conditions such as steady state regime are required. Some realistic simulations show the efficiency of the proposed technique.     

Determination of backscatter sources in surface type targets†

A high-resolution X-band FM-CW radar system has been used to investigate the sources of backscatter in various types of crops, trees and surfaces. This system provided a range resolution in air of 6·67 cm and gave a 16 cm diameter illumination area at the target. The surface targets included concrete walkways, grass, soil and asphalt pavements. Although the surfaces of these targets were the primary sources of backscatter, some subsurface boundaries were located and a volume scatter contribution was evident for some targets.     

What comes first: the workplan or the special request?

How does your MIS Department handle ad hoc requests for I/S projects? CIH Advisory Board member Fran Turisco tells how her MIS Department at the Lahey Clinic deals with this problem and solicits ideas from CIH readers via our "FAX IT BACK" response form.     

ΛCDM type Heckmann–Schuking model and Union 2.1 compilation

We study a ΛCDM type cosmological model in Heckmann-Schucking space-time, by using 287 high redshift (.3 ≤ z ≤ 1.4) SN Ia data on observed absolute magnitude along with their possible error from Union 2.1 compilation. We use the χ² test to compare Union 2.1 compilation observed data and the corresponding theoretical values of the apparent magnitude (m). It is found that the best fit value of (Ω _m )₀, (Ω_Λ)₀ and (Ω _σ )₀ are 0.2940, 0.7058 and 0.0002, respectively, and the derived model represents the features of an accelerating universe which is consistent with the recent astrophysical observations.     

Two-Wave Interactions in the Fermi–Pasta–Ulam Model

This work is devoted to investigating the dynamic properties of the solutions to the boundaryvalue problems associated with the classic Fermi–Pasta–Ulam (FPU) system. We analyze these problems for an infinite-dimensional case where a countable number of roots of characteristic equations tend to an imaginary axis. Under these conditions, we build a special nonlinear partial differential equation that acts as a quasi-normal form, i.e., determines the dynamics of the original boundary-value problem with the initial conditions in a sufficiently small neighborhood of the equilibrium state. The modified Korteweg–deVries (KdV) equation and the Korteweg–de Vries–Burgers (KdVB) equation act as quasi-normal forms depending on the parameter values. Under some additional assumptions, we apply the renormalization procedure to the boundary-value problems obtained. This procedure leads to an infinite-dimensional system of ordinary differential equations. We describe a method for folding this system into a special boundary- value problem, which is an analog of the normal form. The main contribution of this work is investigating the interaction of the waves moving in different directions in the FPU problem by using analytical methods of nonlinear dynamics. It is shown that the mutual influence of the waves is asymptotically small, does not affect their shape, and contributes only to a shift in their speeds, which does not change over time.     

Equilibria in secure strategies in the Bertrand–Edgeworth duopoly

This paper analyzes the Bertrand–Edgeworth duopoly model using a solution concept of Equilibrium in Secure Strategies (EinSS), which describes cautious behavior in noncooperative games. The concept is suitable for studying games where the threats of other players represent an important factor in the decision-making process. We demonstrate that, in some cases where the Bertrand–Edgeworth price duopoly admits no Nash–Cournot equilibria, there exists a unique EinSS with both players choosing an identical equilibrium price lower than the monopoly price. The difference between these prices can be interpreted as an additional reduction in price that allows the players to secure themselves against the mutual threats of undercutting. We formulate and prove a criterion for the EinSS existence.     

Phase equilibria in the Au–In–Sn ternary system

Phase equilibria of the Au–In–Sn system have been investigated by Differential Scanning Calorimetry (DSC), metallographic examination, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) measurements. The 130 ^°C isothermal section of the phase diagram was studied. The ternary diagram shows six three-phase fields, and one ternary Au₄In₃Sn₃ phase, which melts incongruently at 382 ^°C and shows a homogeneity range between 21 and about 30 at.% In, at constant Au/Sn ratio.