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The study of Delay Tolerant Networks (DTNs) has considerably grown in recent years as communication contexts have emerged with needs that go beyond what the Internet could offer. For example, in case of a natural disaster that damages the classic communication network, a delay tolerant network can be implemented ad hoc, to face the challenges imposed by this context. The delay tolerant network is special because there are no permanent end-to-end path between nodes and links characteristics are time-varying. This paper aims to test the performance of the DTN MaxDelivery algorithm in establishing an efficient communication in the context of a post-earthquake situation, that affected the classical communication network. The goal of the algorithm is to maximize the number of high priority messages that manage to reach their destination. A series of simulations are presented to verify the optimal parameters that the network must comply with in order to maximize the message transfer rate. [ABSTRACT FROM AUTHOR]

Machine learning has been widely used in many domains lately and an increasing trend can be observed. New algorithms have been developed and older ones have been improved or combined to get better results. Healthcare is one of the domains that has seen the benefits of using these new computation methods. Considering that early prototypes of artificially intelligent doctors already exist [2], in the not too distant future we could be greeted by robot nurses or even doctors at medical facilities. This paper aims to present, analyze and discuss some of the latest advancements in machine learning from the healthcare point of view. Important aspects that this paper covers are: recently used machine learning algorithms in healthcare, data available for research purpose and the fields that healthcare extends to. A conclusion based on these aspects is drawn, whether there is a need and possibility for potential further development of machine learning algorithms in healthcare. [ABSTRACT FROM AUTHOR]

The problem introduced in this paper (denoted IMFW∞) is to modify the capacities on arcs from a network so that a given feasible flow becomes a maximum flow and the maximum cost of change of the capacities is minimum. This problem is a generalization of the inverse maximum flow problem under l∞ norm (denoted IMF∞, where the per unit cost of modification is equal to 1 on all arcs), which was priviously studied and solved in polynomial time. In this paper, the algorithm for IMF∞ is adapted to solve IMFW∞. [ABSTRACT FROM AUTHOR]

An algorithm for constructing evolutionary tracks for a star with the mass equal to one solar mass is given. The presented model can be applied to the stars belonging to the inferior main sequence, which have the proton-proton reaction as energy source and present a radiative core and a convective shell. This paper presents an original way of resolving the system of equations corresponding to the radiative nucleus by using Taylor's series in close vicinity to the center of the Sun. It also presents the numerical integration and the results for a one billion years aged solar model. [ABSTRACT FROM AUTHOR]

We present a new statistical randomness test based on Walsh-Hadamard transform. This test is a extension of frequency and autocorrelation tests and can detect a general class of defects which can appear in (pseudo)random generators. The test is based on the probability distribution of the Walsh-Hadamard transform. NIST Special Publication 800-22 [10] present two methods of integrating the results of one or more tests based on proportion of passing tests and uniformity of the corresponding P-values. This paper will introduce another two methods of integration of test results based on maximum test statistics and sum of squares test statistics. The integration of test results are independent from the proposed test and may be used by all the statistical tests based on confidence intervals. Some of the applications of the Walsh-Hadamard statistical test and decision procedures are in the following areas: (pseudo)randomness testing, cryptanalytic area and steganographic detection. [ABSTRACT FROM AUTHOR]

The out-of-kilter algorithm is one of the basic algorithms that solve the minimum cost flow problem. Its drawback is that it can improve the objective function at each iteration by a small value. Consequently, it runs in pseudo-polynomial time. In [2], we described a scaling out-of-kilter algorithm for minimum cost flow in networks without positive lower bounds that runs in polynomial time. There are several practical problems (see [1]) that can be reduced to the minimum cost flow problem in a network with positive lower bounds. That is the first reason for which, in this paper, we focus on the transformations that must be made to the scaling out-of-kilter algorithm in order to apply it in networks with positive lower bounds. The second reason for writing this paper is the versatility of the scaling out-of-kilter algorithm. Unlike most network flow algorithms (maximum flow algorithms, minimum cost flow algorithms etc.), for applying the scaling out-of-kilter algorithm in a network with positive lower bounds, we do not need to establish a feasible flow and to determine an equivalent network without positive lower bounds. [ABSTRACT FROM AUTHOR]

As is well-known, surfaces in a 3-dimensional Euclidean Space can be represented locally by means of several types of equations. Though these are mathematically equivalent, the choice of representation can make a difference when it comes to visualizing the surface. More precisely, some representations may produce artifacts in the visualization that are merely a consequence of the visualization process itself. Sometimes, by rewriting equations or by switching to another representation, these can be avoided. In this paper, this phenomenon is explained and demonstrated by means of the new version of the visualization software VISUMATH. Moreover, the new capabilities of the software and the geometry behind it are explained. These include the possibility of dynamically changing the shape of surfaces by altering parameters in the representation. This feature can be useful in examining the precise role of parameters in the equation(s) representing the surface. [ABSTRACT FROM AUTHOR]

Theoretically, the step-size plays a crucial role in the complexity analysis of primal-dual interior-point algorithms. In this paper, we would like to focus on the strategy of how to select the step-size. We propose three choices applied to P*(k)-Linear complementarity problem based on two new kernel functions. The numerical behavior of the primal-dual interior-point algorithm is shown to be improved with these step-size choices. We have significantly reduced the number of the inner iterations and the calculation time of the large-update algorithm. [ABSTRACT FROM AUTHOR]

A generalized network is characterized by arc multipliers that specify which portion of the ow entering an arc at its tail node reaches its head node. In this paper, the goal is to maximize the ow excess at the sink in undirected generalized networks. We show that the results of the directed networks are not satisfied here. We have specifically stated and proved the optimality conditions of the problem. We have also designed an algorithm according to Pulat's algorithm and achieved an effcient version. [ABSTRACT FROM AUTHOR]

In this paper, we introduce an iterative algorithm for approximating a common solution of monotone yosida variational inclusion problem in the framework of p-uniformly convex and uniformly smooth Banach spaces. Using our iterative algorithm, we state and prove a strong convergence theorem for approximating a common solution of the aforementioned problem. We also consider an infinite family of Bregman quasi-nonexpansive mapping and prove its strong convergence result. Our result extends and complements some related results in literature. [ABSTRACT FROM AUTHOR]

In this paper, we develop a generic algorithm for determining a maximum flow in a semi-bipartite network. This algorithm allows only nodes in N1 to be active. For this reason, it performs pushes on individual arcs having both endpoints in N1 or admissible paths of length 2 whose starting and ending nodes are both contained in N1. The running time of this algorithm is O(n21 m). [ABSTRACT FROM AUTHOR]

In this paper we focus on determining a maximum cut containing the smallest number of backward arcs from among all maximum cuts in a given network. We will solve this problem by reducing it to a standard maximum cut problem in a transformed network. [ABSTRACT FROM AUTHOR]

In this paper we consider the problem of inverse maximum flow in planar network (IMFPN), where upper bounds for the flow must be changed as little as possible so that a given feasible flow becomes a maximum flow in the modified network. A strongly polynomial algorithm for solving this problem is proposed. [ABSTRACT FROM AUTHOR]

In the present paper we present simulation results for the two-dimensional Ising model using Tsallis statistics. We compute the q-mean value of the energy per spin and the q-mean value of the absolute magnetization per spin for different lattice sizes using the Metropolis algorithm modified for Tsallis acceptance ratios. The results show that even for q 6= 1 we have a second order phase transition. The critical temperature in the thermodynamical limit depends on the Tsallis entropic index q. [ABSTRACT FROM AUTHOR]

The algorithm presented in this paper solves the minimum flow problem in a parametric network with linear lower bound functions by computing a parametric maximum flow from the sink node to the source node. The algorithm does not work directly in the original parametric network but in the parametric residual network defined as for the parametric maximum flow problem. The complexity of the parametric min-max algorithm is equal to the complexity of the parametric maximum flow algorithm. [ABSTRACT FROM AUTHOR]

An algoritm for constructing tracks for the contractional phase of stars is given. This paper presents an original way of solving the system of equations corresponding to the radiative nucleus by using Taylor's series in close vicinity to the center of stars. We have obtained the form of the Taylor series which are used in the case of undetermination 0/0. [ABSTRACT FROM AUTHOR]

In this paper, we describe the cost scaling algorithm for the minimum cost flow in bipartite networks. The cost scaling algorithm for minimum cost flow problem in general networks, developed by Goldberg and Tarjan, is based on ϵ-optimality conditions. The basic idea behind the cost scaling algorithm for the minimum cost flow in a bipartite network is to perform bipushes from nodes in N1. A bipush is a push over two consecutive admissible arcs. Consequently, a bipush moves the excess from a node in N1 to another node in N1. This approach has all the advantages of the scaling cost algorithm for the minimum cost flow in general networks. Moreover, it has an additional advantage that leads to an improved running time. This additional advantage consists in the fact that, using bipushes instead of pushes, all the nodes in N2 are maintained balanced. Consequently, the running time of the cost scaling algorithm for the minimum cost flow is reduced from O(n2mlog(nB)) to O(n12m log(nB)) when it is applied on bipartite networks. [ABSTRACT FROM AUTHOR]

In this paper, I propose a survey of new results on the Stern identification and signature scheme. I describe coding theory, its application to cryptography and different identification and signature schemes using error correcting codes. Next I briefly describe a secure implementation of the Stern scheme against DPA and an identity based signature scheme. [ABSTRACT FROM AUTHOR]

An effective nonlinear anisotropic diffusion-based algorithm for image restoration is proposed in this work. The technique considered here employs a novel second-order partial differential equation (PDE) model, composed of a hyperbolic equation and several boundary conditions. Our method provides satisfactory feature-preserving filtering results and overcomes successfully the blurring and staircase effects. It also produces sharper edges because of its hyperbolic equation that is based on a second time derivative. The proposed PDE model is well-posed, admitting a unique and weak solution under certain assumptions, which is computed by using an iterative finite difference-based explicit numerical approximation scheme. Some successful restoration experiments and method comparisons are also described in this paper. [ABSTRACT FROM AUTHOR]

In this paper we develop a new algorithm for solving the maximum flow problem in semi-bipartite networks. This algorithm is a specific implementation of the generic algorithm described in [4], obtained by performing passes through the active nodes. During such a pass, all the active nodes are examined in nonincreasing order of their exact distance labels, and their excesses are, partially or totally, moved closer to the sink node. After O(n1²) passes, all the active node excesses are moved to the sink node or back to the source node and a maximum flow is obtained. [ABSTRACT FROM AUTHOR]

Many real world systems are modeled by retrial queuing system. Ana- lytical formulas for this class of systems are complicated and address only particular cases. By algorithmic approach, one studies through simulation the cases that are not studied analytically. In this paper we present the im- plementation of the simulation algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we study minimum ows in network with parametric lower bounds for sink arcs problem. In this problem, the lower bounds for sink arcs are a nonincreasing linear function of a parameter λ, and we wish to determine a minimum ow for q values 0 = λ1; λ2,...,λq of parameter λ. Assume, that 0 = λ1 < λ2 < ... < λq and q ≤ n, where n is a number of nodes. [ABSTRACT FROM AUTHOR]

An algorithm for constructing evolutionary tracks for a star with the mass equal to one solar mass is given. The model presented can be applied to the stars belonging to the inferior main sequence, which have the proton-proton reaction as energy source and present a radiative core and a convective shell. This paper presents an original way of resolving the system of equations cor- responding to the radiative nucleus by using Taylor's series in close vicinity to the center of the Sun. It also presents the numerical integration and the results for a 0.85 billion year solar model. [ABSTRACT FROM AUTHOR]

The article proposes to develop a method for determining the conformity of vector illustration to the laws of composition and design, which will help to engage in artistic work for people without special skills and abilities. The concept of the centre of the composition is analysed. The main criterion of equilibrium is determined - the distance between the optical and composite centre. As the first stage of the developed method, it is offered to define the area of an element and to bring an arbitrary figure to a polygon. An algorithm for determining the area of an object of arbitrary shape has been developed. The process of colour density determination is analysed, and its algorithm is developed. An algorithm for determining the equilibrium of the composition is proposed. A script has been created that implements the method of determining the compliance of vector illustration with the laws of composition and design. A script based on a specific one has been tested during a number of tests. According to the test results, the conclusions about the correct operation of the script were confirmed. A prototype of an automation system for creating vector illustrations in Adobe Illustrator has been created. [ABSTRACT FROM AUTHOR]

Energy consumption and coverage problem are two important issues in wireless sensor networks. In this paper, we are going to maintain sensing coverage in a heterogeneous wireless sensor network with an adjustable sensing range that is randomly developed, in such a way that small numbers of sensor nodes are active, and therefore a small amount of energy is consumed, and the network lifetime increases. This is a multi-objective optimization problem. We used a Multi-Objective Evolutionary Algorithm based on Decomposition (MOEA/D) for solving this problem.The experimental results demonstrated that MOEA/D can perform better than NSGA-II. [ABSTRACT FROM AUTHOR]

An image overlapping algorithm, taking into account certain properties of objects identified in the images (average intensity, movement speed, etc) is proposed. The algorithm minimizes both memory and time complexity and it can be used in various applications, especially in medical imaging analysis. The idea behind the proposed algorithm is surface merging and interpolation. [ABSTRACT FROM AUTHOR]

Given an instance of the minimum cost flow problem, the corresponding inverse problem is to modify the arc costs as little as possible so that a given feasible flow becomes optimal to the modified minimum cost flow problem. In this article, we study this inverse problem in that the modifications are measured by the weighted bottleneck-type Hamming distance. We present a new efficient algorithm to solve the inverse problem. Finally, we theoretically compare the proposed algorithm with the previous one. [ABSTRACT FROM AUTHOR]

The article formulates and studies the generalisation of the bi-criteria minimum cost flow problem for the case of dynamic flows. The approach is based on reducing the dynamic problem to a static bi-criteria problem on a time-expanded network with constant capacities, fixed transit times on arcs and for a flow leaving the source node only at time θ = 0 and solving the problem via network-simplex based algorithm. [ABSTRACT FROM AUTHOR]

This article covers the minimum-cost flow problem and intends to offer an illustrative tool for efficient education in sciences, especially in the field of flows in networks. In the first part, the article concerns with the basic concepts of the problem itself. The second part describes the "Successive Shortest Path Algorithm" for finding a minimum cost flow in a network and in the final part, a set of two interactive applications of the problem are covered. The using of AWT (Java) in the developed applets brings the advantage of a sophisticated set of Graphical User Interface which allows step by step solving of both shortest path and minimum cost flow problems. [ABSTRACT FROM AUTHOR]

We present three algorithms for finding minimum flows in networks with arcs capacities using the dynamic tree implementation. Also, we present an example for one of these algorithms. [ABSTRACT FROM AUTHOR]