Sample records for streams problems solutions

  1. Calculus problems and solutions

    Ginzburg, A


    Ideal for self-instruction as well as for classroom use, this text helps students improve their understanding and problem-solving skills in analysis, analytic geometry, and higher algebra. More than 1,200 problems appear in the text, with concise explanations of the basic notions and theorems to be used in their solution. Many are followed by complete answers; solutions for the others appear at the end of the book. Topics include sequences, functions of a single variable, limit of a function, differential calculus for functions of a single variable, fundamental theorems and applications of dif

  2. XML problem, design, solution

    Amiano, Mitch; Ethier, Kay; Thomas, Michael D


    Offering a unique approach to learning XML, this book walks readers through the process of building a complete, functional, end-to-end XML solutionFeatured case study is an online business product catalog that includes reports, data input/output, workflow, stylesheet formatting, RSS feeds, and integration with external services like Google, eBay, and AmazonThe format of presenting a problem and working through the design to come up with a solution enables readers to understand how XML markup allows a business to share data across applications internally or with partners or customers even thoug

  3. Europeanisation: Solution or problem?

    Claudio M. Radaelli


    Full Text Available Is there something new in recent research on Europeanisation? Or should we go back to what we already know about political integration in Europe and avoid the term? This article reviews recent work in four steps: the identification of the specific domain of Europeanisation; the relationship between Europeanisation, on the one hand, and governance, institutions, and discourse, on the other; the methodological problems and the models emerging in this new field of research; and an assessment of the results arising out of theoretical and empirical research. One theme throughout the article is that, in order to develop a progressive agenda, Europeanisation should be seen as a problem, not as a solution. It is neither a new theory, nor an ad-hoc approach. Rather, it is a way of orchestrating existing concepts and to contribute to cumulative research in political science. Europeanisation does not provide any simple fix to theoretical or empirical problems. Quite the opposite, it can deliver if approached as a set of puzzles. A problem in search of explanation not the explanation itself (Gualini 2003. The conclusion is that Europeanisation has contributed to the emergence of new insights, original explanations, and interesting questions on three important issues: the understanding and analysis of 'impact', how to endogeneise international governance in models of domestic politics, and the relationship between agency and change. These three issues are prominent in the research agendas of international relations, theoretical policy analysis, and comparative politics. To contribute to major issues at the core of political science is a valuable result for a relatively new field of inquiry.

  4. Solutions of fractional diffusion problems

    Rabha W. Ibrahim


    Full Text Available Using the concept of majorant functions, we prove the existence and uniqueness of holomorphic solutions to nonlinear fractional diffusion problems. The analytic continuation of these solutions is studied and the singularity for two cases are posed.

  5. Analytical solution based on stream-aquifer interactions in partially penetrating streams

    Yong Huang


    Full Text Available An analytical solution of drawdown caused by pumping is developed in an aquifer hydraulically connected to a finite-width stream on the condition of two streams. The proposed analytical solution modified Hunt’s analytical solution and not only considers the effect of stream width on drawdown, but also takes the distribution of drawdown on the interaction of two streams into account. Advantages of the solution include its simple structure, consisting of the Theis well function, parameters of aquifer and streambed semipervious material. The calculated results show that the proposed analytical solution agrees well with the previous solution and the errors between the two solutions are equal to zero on the condition of a stream without considering the effect of stream width. Also, deviations between the two analytical solutions increase with the increase of stream width. Furthermore, four cases are studied to discuss the effect of two streams on drawdown. It assumes that some parameters are changeable, and other parameters are constant, such as stream width, the distance between stream and pumping well, stream recharge rate, and the leakance coefficient of streambed semipervious material, etc. The analytical solution may provide estimates for parameters of aquifer and streambed semipervious material using the Type Curve Method through the data of field test.

  6. Analytical solution based on stream-aquifer interactions in partially penetrating streams

    Yong HUANG; Zhi-fang ZHOU; Zhong-bo YU


    An analytical solution of drawdown caused by pumping was developed for an aquifer partially penetrated by two streams.The proposed analytical solution modifies Hunt's analytical solution and considers the effects of stream width and the interaction of two streams on drawdown.Advantages of the solution include its simple structure,consisting of the Theis well function and parameters of aquifer and streambed semipervious material.The calculated results show that the proposed analytical solution agrees with a previously developed acceptable solution and the errors between the two solutions are equal to zero without consideration of the effect of stream width.Also,deviations between the two analytical solutions incrcase with stream width.Four cases were studied to examine the effect of two streams on drawdown,assuming that some parameters were changeable,and other parameters were constant,such as the stream width,the distance between the stream and the pumping well,the stream recharge rate,and the leakage coefficient of streambed semipervious material.

  7. Fluid mechanics problems and solutions

    Spurk, Joseph H


    his collection of over 200 detailed worked exercises adds to and complements the textbook Fluid Mechanics by the same author, and illustrates the teaching material through examples. In the exercises the fundamental concepts of Fluid Mechanics are applied to obtaining the solution of diverse concrete problems, and in doing this the student's skill in the mathematical modeling of practical problems is developed. In addition, 30 challenging questions without detailed solutions have been included, and while lecturers will find these questions suitable for examinations and tests, the student himself can use them to check his understanding of the subject.

  8. Network Monitoring as a Streaming Analytics Problem

    Gupta, Arpit


    Programmable switches make it easier to perform flexible network monitoring queries at line rate, and scalable stream processors make it possible to fuse data streams to answer more sophisticated queries about the network in real-time. Unfortunately, processing such network monitoring queries at high traffic rates requires both the switches and the stream processors to filter the traffic iteratively and adaptively so as to extract only that traffic that is of interest to the query at hand. Others have network monitoring in the context of streaming; yet, previous work has not closed the loop in a way that allows network operators to perform streaming analytics for network monitoring applications at scale. To achieve this objective, Sonata allows operators to express a network monitoring query by considering each packet as a tuple and efficiently partitioning each query between the switches and the stream processor through iterative refinement. Sonata extracts only the traffic that pertains to each query, ensuring that the stream processor can scale traffic rates of several terabits per second. We show with a simple example query involving DNS reflection attacks and traffic traces from one of the world\\'s largest IXPs that Sonata can capture 95% of all traffic pertaining to the query, while reducing the overall data rate by a factor of about 400 and the number of required counters by four orders of magnitude. Copyright 2016 ACM.

  9. Mobile authentication problems and solutions

    Jakobsson, Markus


    Mobile Authentication: Problems and Solutions looks at human-to-machine authentication, with a keen focus on the mobile scenario. Human-to-machine authentication is a startlingly complex issue. In the old days of computer security-before 2000, the human component was all but disregarded. It was either assumed that people should and would be able to follow instructions, or that end users were hopeless and would always make mistakes. The truth, of course, is somewhere in between, which is exactly what makes this topic so enticing. We cannot make progress with human-to-machine authentication with

  10. Fuel cells problems and solutions

    Bagotsky, Vladimir S


    The comprehensive, accessible introduction to fuel cells, their applications, and the challenges they pose Fuel cells-electrochemical energy devices that produce electricity and heat-present a significant opportunity for cleaner, easier, and more practical energy. However, the excitement over fuel cells within the research community has led to such rapid innovation and development that it can be difficult for those not intimately familiar with the science involved to figure out exactly how this new technology can be used. Fuel Cells: Problems and Solutions, Second Edition addresses this i

  11. Silverlight 4 Problem - Design - Solution

    Lecrenski, Nick


    A hands-on guide to Microsoft's latest rich application development technology: Silverlight 4. Silverlight 4 is the newest version of the rich Internet application toolkit that provides support for .NET capabilities over the Internet. With this latest release of Silverlight, Microsoft has revolutionized the way that Web applications can be created. This book uses the popular Problem – Design – Solution strategy to demonstrate how to harness the power and abilities of Silverlight 4 to add value to the overall user experience of a Web site. Using a Web site created by the author as a reference p

  12. The Universal Primer - An open source solution for archiving, organizing and streaming live lectures

    Christoffersen, Marc Juul; Panton, Hans Christian Hansen; Krajowski-Kukiel, Maciej;


    . The goal of the Universal Primer is to address these problems, and allow anyone, anywhere, to teach or learn anything that can be reasonably taught or learned through a computer. The Universal Primer is 1: A fully open source solution for streaming live lectures. And 2: A Wikipedia-like website...

  13. Solution to reverse refraction problem

    Pavelyev, A. G.


    The reverse refraction problem (determination of radial profile of refractive index in planetary atmospheres, such as Earth, from radio probe measurements) is formulated as a bistatic radar problem for a spherically symmetric medium. The modified refractive index n(r)r (a-radius at which the refraction angle as function of relative distance is measured) is assumed to reach extreme values at the upper boundary r sub 1 or at observation level. Before the corresponding Fredholm equation of the first kind can be solved, it must be well-conditioned in the Tikhonov sense. This is done here by two quasi-optimum integral transformation variants with respect to the measurement function and subsequent simplified regularization. The first method is two successive Fourier cosine transformations followed by an Abel transformation, with the possibility of discrete Fourier transformations and numerical Abel transformation. The second method is twofold discrete Fourier transformation. Both yield solutions readily evaluated by simple algorithms. Regularization is effected by approximating functions satisfying the two fundamental conditions for convergence required of the measurement function.

  14. Multiple Solutions Involving Geoboard Problems.

    Smith, Lyle R.


    Illustrates various methods to determine the perimeter and area of triangles and polygons formed on the geoboard. Methods utilize algebraic techniques, trigonometry, geometric theorems, and analytic geometry to solve problems and connect a variety of mathematical concepts. (MDH)


    Khanna Surabhi; Nasa Atul; Garg Arun


    The pharmaceutical industry is under extraordinary strain. Facing the wrath of consumers because of the cost of products, constantly answering the questions of state and federal legislators looking to control health care costs, and losing value in the marketplace, the industry’s hands are more than full. A less discussed but substantial problem impacts all of pharmaceutical industry’s other problems, counterfeiting. The World Health Organization estimates that counterfeit drugs make up about ...

  16. The Overview and Appliance of some Streaming Video software solutions

    Qin, Yan


    This paper introduces the basic streaming media technology, the streaming media system structure, principles of streaming media technology; streaming media file formats and so on. After that, it discusses the use streaming media in distance education, broadband video on demand, Internet broadcasting, video conferences and a more detailed exposition in streaming media. As the existing technology has been unable to satisfy the increasing needs of the Internet users, the streaming media technol...


    Khanna Surabhi


    Full Text Available The pharmaceutical industry is under extraordinary strain. Facing the wrath of consumers because of the cost of products, constantly answering the questions of state and federal legislators looking to control health care costs, and losing value in the marketplace, the industry’s hands are more than full. A less discussed but substantial problem impacts all of pharmaceutical industry’s other problems, counterfeiting. The World Health Organization estimates that counterfeit drugs make up about 10 percent of the global medicine market, and more than 25 percent in developing countries. With counterfeit drugs increasingly finding their way into global distribution chains and ultimately into patients' mouths, it is essential that pharmaceutical companies have effective enforcement strategies to combat the manufacture and distribution of counterfeit drugs.

  18. Solution strategies for constant acceleration problems

    Wheaton, S. M.; Binder, P.-M.


    We discuss strategies for the general solution of single-step 1D constant acceleration problems. In a slightly restricted form, these problems have five variables (Δx, v 0, v, a and t) and two independent equations, so three variables must be given to solve for the other two, giving 10 cases. Instead of the haphazard solution of individual problems, we advocate teaching a strategy for tackling the entire class of problems. We enumerate the possible strategies, and present in detail one which reveals a number of interesting special cases and also allows the possibility of developing an automatic problem generator and solver.

  19. A Mathematical Solution to the Motorway Problem

    Michaelson, Matthew T.


    This article presents a mathematical solution to a motorway problem. The motorway problem is an excellent application in optimisation. As it integrates the concepts of trigonometric functions and differentiation, the motorway problem can be used quite effectively as the basis for an assessment tool in senior secondary mathematics subjects.…


    G. Fyliuk


    Full Text Available The paper studies current situation at the Ukrainian electric power industry. The problems which prevent development of the industry under current conditions are analyzed. The problems of the cross-subsidization are exposed. The ways of the problems solutions are offered.

  1. Real analysis and probability solutions to problems

    Ash, Robert P


    Real Analysis and Probability: Solutions to Problems presents solutions to problems in real analysis and probability. Topics covered range from measure and integration theory to functional analysis and basic concepts of probability; the interplay between measure theory and topology; conditional probability and expectation; the central limit theorem; and strong laws of large numbers in terms of martingale theory.Comprised of eight chapters, this volume begins with problems and solutions for the theory of measure and integration, followed by various applications of the basic integration theory.

  2. Problems and solutions in quantum physics

    Ficek, Zbigniew


    This book contains tutorial problems with solutions for the textbook Quantum Physics for Beginners. The reader studying the abstract field of quantum physics needs to solve plenty of practical, especially quantitative, problems. This book places emphasis on basic problems of quantum physics together with some instructive, simulating, and useful applications. A considerable range of complexity is presented by these problems, and not too many of them can be solved using formulas alone.

  3. International young physicists' tournament problems & solutions 2014

    Gao, Wenli


    International Young Physicists' Tournament (Iypt), is one of the most prestigious international physics contests among high school students. This book is based on the solutions of 2014 Iypt problems. The authors are undergraduate students who participated in the Cupt (Chinese Undergraduate Physics Tournament). It is intended as a college level solution to the challenging open-ended problems. It provides original, quantitative solutions in fulfilling seemingly impossible tasks. This book is not limited to the tasks required by the problems and it is not confined to the models and methods in present literatures. Many of the articles include modification and extension to existing models in references, or derivation and computation based on fundamental physics. This book provides quantitative solutions to practical problems in everyday life. This is a good reference book for undergraduates, advanced high-school students, physics educators and curious public interested in the intriguing phenomena in daily life.

  4. Solute specific scaling of inorganic nitrogen and phosphorus uptake in streams


    Stream ecosystem processes such as nutrient cycling may vary with stream position in the watershed. Using a scaling approach, we examined the relationship between stream size and nutrient uptake length, which represents the mean distance that a dissolved solute travels prior to removal from the water column. Ammonium uptake length increased proportionally with stream size measured as specific discharge (discharge/stream width) with a scaling exponent = 1.01. In contrast, the scaling ex...

  5. Piecewise polynomial solutions to linear inverse problems

    Hansen, Per Christian; Mosegaard, K.


    We have presented a new algorithm PP-TSVD that computes piecewise polynomial solutions to ill-posed problems, without a priori knowledge about the positions of the break points. In particular, we can compute piecewise constant functions that describe layered models. Such solutions are useful, e.g.......g., in seismological problems, and the algorithm can also be used as a preprocessor for other methods where break points/discontinuities must be incorporated explicitly....




    Under suitable conditions on f(·, u), it is shown that the two-point boundary value problem(φp(u'))'+ λq(t)f(u)=0 in (0, 1),u(0)=u(1)=0,has two positive solution or at least one positive solution for A in a compatible interval.

  7. The Pizza Problem: A Solution with Sequences

    Shafer, Kathryn G.; Mast, Caleb J.


    This article addresses the issues of coaching and assessing. A preservice middle school teacher's unique solution to the Pizza problem was not what the professor expected. The student's solution strategy, based on sequences and a reinvention of Pascal's triangle, is explained in detail. (Contains 8 figures.)

  8. A General Solution for Troesch's Problem

    Hector Vazquez-Leal


    Full Text Available The homotopy perturbation method (HPM is employed to obtain an approximate solution for the nonlinear differential equation which describes Troesch’s problem. In contrast to other reported solutions obtained by using variational iteration method, decomposition method approximation, homotopy analysis method, Laplace transform decomposition method, and HPM method, the proposed solution shows the highest degree of accuracy in the results for a remarkable wide range of values of Troesch’s parameter.

  9. Problems and Solutions in Heterogeneous Cooperative Learning



    Heterogeneous cooperative learning,as the best kind of cooperative learning,is quite often adopted to make utmost use of the human power in second language learning. On the other hand ,some problems existing in it make it far from satisfactory. In this thesis ,the writer will analyse the problems and put forward some solutions to perfect HCL.

  10. Princeton problems in physics with solutions

    Newbury, Nathan; Ruhl, John E; Staggs, Suzanne T; Thorsett, Stephen E


    Aimed at helping the physics student to develop a solid grasp of basic graduate-level material, this book presents worked solutions to a wide range of informative problems. These problems have been culled from the preliminary and general examinations created by the physics department at Princeton University for its graduate program. The authors, all students who have successfully completed the examinations, selected these problems on the basis of usefulness, interest, and originality, and have provided highly detailed solutions to each one. Their book will be a valuable resource not only to o

  11. Clustering of solutions in hard satisfiability problems

    Ardelius, John; Aurell, Erik; Krishnamurthy, Supriya


    We study numerically the solution space structure of random 3-SAT problems close to the SAT/UNSAT transition. This is done by considering chains of satisfiability problems, where clauses are added sequentially to a problem instance. Using the overlap measure of similarity between different solutions found on the same problem instance, we examine geometrical changes as a function of α. In each chain, the overlap distribution is first smooth, but then develops a tiered structure, indicating that the solutions are found in well separated clusters. On chains of not too large instances, all remaining solutions are eventually observed to be found in only one small cluster before vanishing. This condensation transition point is estimated by finite size scaling to be αc = 4.26 with an apparent critical exponent of about 1.7. The average overlap value is also observed to increase with α up to the transition, indicating a reduction in solutions space size, in accordance with theoretical predictions. The solutions are generated by a local heuristic, ASAT, and compared to those found by the Survey Propagation algorithm up to αc.

  12. Complete Solutions to Extended Stokes' Problems

    Chi-Min Liu


    Full Text Available The main object of the present study is to theoretically solve the viscous flow of either a finite or infinite depth, which is driven by moving plane(s. Such a viscous flow is usually named as Stokes' first or second problems, which indicates the fluid motion driven by the impulsive or oscillating motion of the boundary, respectively. Traditional Stokes' problems are firstly revisited, and three extended problems are subsequently examined. Using some mathematical techniques and integral transforms, complete solutions which can exactly capture the flow characteristics at any time are derived. The corresponding steady-state and transient solutions are readily determined on the basis of complete solutions. Current results have wide applications in academic researches and are of significance for future studies taking more boundary conditions and non-Newtonian fluids into account.

  13. A simple solution to Archimedes' cattle problem

    Nygrén, A. (Antti)


    Abstract A simple solution to the classical Archimedes' cattle problem is given. Unlike the previous ones, this is mainly based on elementary mathematics which, at least in principle, would have been available to the mathematicians of the classical era. The solution applies linear transformation and infinite descent in solving quadratic Diophantine equations in a manner which does not explicitly take advantage of continued fractions. The idea is to create a sequence of tran...

  14. A solution to the problem of time

    Shlaer, Benjamin


    Despite the severe ultraviolet problems with quantum gravity, infrared phenomena such as eternal inflation and black hole evaporation should enjoy fully quantum mechanical unitary time evolution. Currently this is not possible, the impediment being what is known as the problem of time. Here, we provide a solution by promoting the cosmological constant \\Lambda to a Lagrange multiplier constraining the metric volume element to be manifestly a total derivative. Because \\Lambda appears linearly in the Hamiltonian constraint, it unitarily generates time evolution, yielding a functional Schroedinger equation for gravity. Two pleasant side effects of this construction are that vacuum energy is completely sequestered from the cosmological constant problem, much like in unimodular gravity, and the natural foliation provided by the time variable defines a sensible solution to the measure problem.

  15. Semantic Solutions to Program Analysis Problems

    Tobin-Hochstadt, Sam


    Problems in program analysis can be solved by developing novel program semantics and deriving abstractions conventionally. For over thirty years, higher-order program analysis has been sold as a hard problem. Its solutions have required ingenuity and complex models of approximation. We claim that this difficulty is due to premature focus on abstraction and propose a new approach that emphasizes semantics. Its simplicity enables new analyses that are beyond the current state of the art.

  16. Viable Solutions for seemingly Intractable Problems

    Ashok Natarajan


    Full Text Available Life is filled with seemingly intractable problems. But life wisdom affirms that if there is a problem, there must be a solution. Or better yet, the solution to the problem lies within the problem itself. Problems have their roots in disharmony. Disharmony arises when a part separates itself from the whole and acts independently of the wider reality of which it is a part, as financial markets have separated themselves from the real economy and economy has detached itself from social and ecological consequences. Insistence on out-moded approaches under new conditions generates intractable problems, as when the framework of a heterogeneous nation-state is employed for the dominance of a single ethnic or religious group. Knowledge and culture are the supreme values of a society and core element of its capacity for accomplishment and development, yet both tend to be exclusively possessed by elites for their own benefit, rather than freely distributed to maximize their impact on society as a whole. Society evolves by the transformation of ignorance into knowledge. Life evolves by organization. The linking and integration of social organizations spur development. Mind itself is an organization and powerful force for development. Energy makes organization more efficient. Any problem can be solved by raising the effectiveness of energy by converting it into skill or capacity and transforming it into power through organization. What one person sees as a problem is an opportunity for another with wider vision. The difference in perception accounts for the difference in levels of accomplishment. So, those with the right perspective see opportunities where others see insolvable problems. Current problems are the result of irrationality, refusal to benefit from past experience and insistence on repeating past errors. Modern science, which was born to fight the superstition of religion, has become a source of superstition. Fully availing of the latest

  17. The world solution for world problems : the problem, its cause, its solution

    León, L.


    The book discusses the main world problem of today, which is the gradual, but lethal change of the soil and atmosphere, the main cause, which is the world-wide overpopulation, and the main solution, which is world government by lottocracy. It is a recipe for the solution of the one and only problem

  18. The world solution for world problems : the problem, its cause, its solution

    León, L.


    The book discusses the main world problem of today, which is the gradual, but lethal change of the soil and atmosphere, the main cause, which is the world-wide overpopulation, and the main solution, which is world government by lottocracy. It is a recipe for the solution of the one and only problem

  19. Nature, Human Nature, and Solutions to Problems.

    Pedrini, D. T.; Pedrini, B. C.

    This paper promotes an undergraduate course that would discuss the great ideas of Plato, St. Paul, Karl Marx, Sigmund Freud, Jean Paul Sartre, B. F. Skinner, and Konrad Lorenz. This course would help students understand human values and behaviors while focusing on historical, world, and national problems. Tentative solutions would then be…

  20. Periodic Solutions for Circular Restricted -Body Problems

    Xiaoxiao Zhao


    Full Text Available For circular restricted -body problems, we study the motion of a sufficiently small mass point (called the zero mass point in the plane of equal masses located at the vertices of a regular polygon. By using variational minimizing methods, for some , we prove the existence of the noncollision periodic solution for the zero mass point with some fixed wingding number.




    In this paper, we study a nonlinear Dirichlet problem on a smooth bounded domain, in which the nonlinear term is asymptotically linear, not superlinear, at infinity and sublinear near the origin. By using Mountain Pass Theorem, we prove that there exist at least two positive solutions under suitable assumptions on the nonlinearity.




    Under the framework of a real Hilbert space, we introduce a new iterative method for finding a common element of the set of solution of a general equilibrium problem and the set of fixed points of a nonexpansive semigroup. Moreover, a numerical example is presented. This example grantee the main result of the paper.

  3. The Hubble Space Telescope: Problems and Solutions.

    Villard, Ray


    Presented is the best understanding of the flaw discovered in the optics of the Hubble Space Telescope and the possible solutions to the problems. The spherical aberration in the telescope's mirror and its effect on the quality of the telescope's imaging ability is discussed. (CW)

  4. Nature, Human Nature, and Solutions to Problems.

    Pedrini, D. T.; Pedrini, B. C.

    This paper promotes an undergraduate course that would discuss the great ideas of Plato, St. Paul, Karl Marx, Sigmund Freud, Jean Paul Sartre, B. F. Skinner, and Konrad Lorenz. This course would help students understand human values and behaviors while focusing on historical, world, and national problems. Tentative solutions would then be…

  5. Possible solution of the quarkonium polarization problem

    Baranov, S.P. [P.N. Lebedev Institute of Physics, Moscow (Russian Federation)


    We address the problem of J/ψ spin alignment in hadron-hadron collisions and propose a natural solution to it using an extended nonrelativistic QCD model where the emission of soft gluons is treated as a series of explicit color-electric dipole transitions.

  6. Operations research problems statements and solutions

    Poler, Raúl; Díaz-Madroñero, Manuel


    The objective of this book is to provide a valuable compendium of problems as a reference for undergraduate and graduate students, faculty, researchers and practitioners of operations research and management science. These problems can serve as a basis for the development or study of assignments and exams. Also, they can be useful as a guide for the first stage of the model formulation, i.e. the definition of a problem. The book is divided into 11 chapters that address the following topics: Linear programming, integer programming, non linear programming, network modeling, inventory theory, queue theory, tree decision, game theory, dynamic programming and markov processes. Readers are going to find a considerable number of statements of operations research applications for management decision-making. The solutions of these problems are provided in a concise way although all topics start with a more developed resolution. The proposed problems are based on the research experience of the authors in real-world com...

  7. DNA computing of solutions to knapsack problems.

    Henkel, Christiaan V; Bäck, Thomas; Kok, Joost N; Rozenberg, Grzegorz; Spaink, Herman P


    One line of DNA computing research focuses on parallel search algorithms, which can be used to solve many optimization problems. DNA in solution can provide an enormous molecular library, which can be searched by molecular biological techniques. We have implemented such a parallel search for solutions to knapsack problems, which ask for the best way to pack a knapsack of limited volume. Several instances of knapsack problems were solved using DNA. We demonstrate how the computations can be extended by in vivo translation of the DNA library into protein. This combination of DNA and protein allows for multi-criterion optimization. The knapsack computations performed can then be seen as protein optimizations, one of the most complex computations performed by natural systems.

  8. Spring Recipes A Problem-solution Approach

    Long, Josh; Mak, Gary


    With over 3 Million users/developers, Spring Framework is the leading "out of the box" Java framework. Spring addresses and offers simple solutions for most aspects of your Java/Java EE application development, and guides you to use industry best practices to design and implement your applications. The release of Spring Framework 3 has ushered in many improvements and new features. Spring Recipes: A Problem-Solution Approach, Second Edition continues upon the bestselling success of the previous edition but focuses on the latest Spring 3 features for building enterprise Java applications.

  9. On approximative solutions of multistopping problems

    Faller, Andreas; 10.1214/10-AAP747


    In this paper, we consider multistopping problems for finite discrete time sequences $X_1,...,X_n$. $m$-stops are allowed and the aim is to maximize the expected value of the best of these $m$ stops. The random variables are neither assumed to be independent not to be identically distributed. The basic assumption is convergence of a related imbedded point process to a continuous time Poisson process in the plane, which serves as a limiting model for the stopping problem. The optimal $m$-stopping curves for this limiting model are determined by differential equations of first order. A general approximation result is established which ensures convergence of the finite discrete time $m$-stopping problem to that in the limit model. This allows the construction of approximative solutions of the discrete time $m$-stopping problem. In detail, the case of i.i.d. sequences with discount and observation costs is discussed and explicit results are obtained.

  10. Hilbert's seventh problem solutions and extensions

    Tubbs, Robert


    This exposition is primarily a survey of the elementary yet subtle innovations of several mathematicians between 1929 and 1934 that led to partial and then complete solutions to Hilbert’s Seventh Problem (from the International Congress of Mathematicians in Paris, 1900). This volume is suitable for both mathematics students, wishing to experience how different mathematical ideas can come together to establish results, and for research mathematicians interested in the fascinating progression of mathematical ideas that solved Hilbert’s problem and established a modern theory of transcendental numbers. .

  11. Development of solutions to benchmark piping problems

    Reich, M; Chang, T Y; Prachuktam, S; Hartzman, M


    Benchmark problems and their solutions are presented. The problems consist in calculating the static and dynamic response of selected piping structures subjected to a variety of loading conditions. The structures range from simple pipe geometries to a representative full scale primary nuclear piping system, which includes the various components and their supports. These structures are assumed to behave in a linear elastic fashion only, i.e., they experience small deformations and small displacements with no existing gaps, and remain elastic through their entire response. The solutions were obtained by using the program EPIPE, which is a modification of the widely available program SAP IV. A brief outline of the theoretical background of this program and its verification is also included.

  12. Challenging problems and solutions in intelligent systems

    Grzegorzewski, Przemysław; Kacprzyk, Janusz; Owsiński, Jan; Penczek, Wojciech; Zadrożny, Sławomir


    This volume presents recent research, challenging problems and solutions in Intelligent Systems– covering the following disciplines: artificial and computational intelligence, fuzzy logic and other non-classic logics, intelligent database systems, information retrieval, information fusion, intelligent search (engines), data mining, cluster analysis, unsupervised learning, machine learning, intelligent data analysis, (group) decision support systems, intelligent agents and multi-agent systems, knowledge-based systems, imprecision and uncertainty handling, electronic commerce, distributed systems, etc. The book defines a common ground for sometimes seemingly disparate problems and addresses them by using the paradigm of broadly perceived intelligent systems. It presents a broad panorama of a multitude of theoretical and practical problems which have been successfully dealt with using the paradigm of intelligent computing.

  13. Flow Data for Solute Transport Modeling from Tracer Experiments in a Stream Not Continuously Gaining Water

    Bencala, K. E.; Kimball, B. A.; Gooseff, M. N.


    In-stream tracer experiments are a well-established method for determining flow data to be incorporated in solute transport modeling. For a gaining stream, this method is implemented to provide spatial flow data at scales of minutes and tens of meters without physical disturbance to the flow of water, the streambed, or biota. Of importance for solute transport modeling, solute inflow loading along the stream can be estimated with this spatial data. The tracer information can also be interpreted to characterize hyporheic exchange time-scales for a stream with hyporheic exchange flowpaths (HEFs) that are short relative to the distance over which the stream gains water. The interpretation of tracer data becomes uncertain for a stream that is not gaining water continuously over intended study reach. We demonstrate, with straight-forward mass-balances, uncertainties for solute loading which arise in the analysis of streams locally losing water while predominantly gaining water (and solutes) over a larger scale. With field data from Mineral Creek (Silverton, Colorado) we illustrate the further uncertainty distinguishing HEFs from (locally) losing segments of the stream. Comparison of bromide tracer with ambient sulfate concentrations suggests that subsurface inflows and outflows, concurrent with likely HEFs, occur in a hydrogeochemical setting of multiple, dispersed and mixed, sources of water along a 64 m sub-reach of the predominately gaining, but locally losing, stream. To compute stream-reach mass-balances (the simplest of water quality models) there is a need to quantitatively define the character and source of contaminants entering streams from ground-water pathways, as well as the potential for changes in water chemistry and contaminant concentrations along flow paths crossing the sediment-water interface. Identification of inflow solute mass requires quantifying water gain, loss, and hyporheic exchange in addition to concentration.

  14. Optimal Solutions for the Temporal Precedence Problem

    Brodal, Gerth Stølting; Makris, Christos; Sioutas, Spyros;


    a in the structure, while the operation precedes (a,b) returns true iff element a was inserted before element b temporally. In [11] a solution was provided to the problem with worst-case time complexity O (log log n ) per operation and O(n log log n) space, where n is the number of elements inserted. It was also...... demonstrated that the precedes operation has a lower bound of Ω (log log n ) for the Pure Pointer Machine model of computation. In this paper we present two simple solutions with linear space and worst-case constant insertion time. In addition, we describe two algorithms that can handle the precedes (a...

  15. Android Recipes A Problem-Solution Approach

    Friesen, Jeff


    Android continues to be one of the leading mobile OS and development platforms driving today's mobile innovations and the apps ecosystem. Android appears complex, but offers a variety of organized development kits to those coming into Android with differing programming language skill sets. Android Recipes: A Problem-Solution Approach guides you step-by-step through a wide range of useful topics using complete and real-world working code examples. In this book, you'll start off with a recap of Android architecture and app fundamentals, and then get down to business and build an app with Google'

  16. Healthcare industry problems call for cooperative solutions.

    Schramm, C J


    The complexity of problems facing American health care--from extending health benefits to the uninsured to caring for people with acquired immune deficiency syndrome--require cooperative solutions involving providers, insurers, and policy makers. A spokesman for the health insurance industry presents ideas about the future of health care and discusses the role of insurers in meeting the challenges ahead. Among the items on the agenda: further growth of managed care; continued attempts to control costs and utilization; and sharing the burden of risk with consumers.

  17. Basic Health Physics: Problems and Solutions

    Bevelacqua, Joseph John


    Radiation litigation, the cleanup and decommissioning of nuclear facilities, radon exposure, nuclear medicine, food irradiation, stricter regulatory climate--these are some of the reasons health physics and radiation protection professionals are increasingly called upon to upgrade their skills. Designed to prepare candidates for the American Board of Health Physics Comprehensive examination (Part I) and other certification examinations, Basic Health Physics: Problems and Solutions introduces professionals in the field to radiation protection principles and their practical application in routine and emergency situations. It features more than 650 worked examples illustrating concepts under discussion along with an in-depth coverage of sources of radiation, standards and regulations, biological effects of ionizing radiation, instrumentation, external and internal dosimetry, counting statistics, monitoring and interpretations, operational health physics, transportation and waste, nuclear emergencies, and more. Reflecting for the first time the true scope of health physics at an introductory level, Basic Health Physics: Problems and Solutions gives readers the tools to properly evaluate challenging situations in all areas of radiation protection, including the medical, university, power reactor, fuel cycle, research reactor, environmental, non-ionizing radiation, and accelerator health physics.

  18. Struggles and Solutions for Streaming Video in the Online Classroom

    Fruin, Christine


    The upcoming round of exemptions to the Digital Millennium Copyright Act of 1998 anticircumvention provision and the questions raised by the copyright infringement lawsuit filed against the against University of California, Los Angeles (UCLA) for its streaming video practices illustrate the problematic state of the law concerning the digitization…

  19. Struggles and Solutions for Streaming Video in the Online Classroom

    Fruin, Christine


    The upcoming round of exemptions to the Digital Millennium Copyright Act of 1998 anticircumvention provision and the questions raised by the copyright infringement lawsuit filed against the against University of California, Los Angeles (UCLA) for its streaming video practices illustrate the problematic state of the law concerning the digitization…

  20. Solution of the Generalized Noah's Ark Problem.

    Billionnet, Alain


    The phylogenetic diversity (PD) of a set of species is a measure of the evolutionary distance among the species in the collection, based on a phylogenetic tree. Such a tree is composed of a root, internal nodes, and leaves that correspond to the set of taxa under study. With each edge of the tree is associated a non-negative branch length (evolutionary distance). If a particular survival probability is associated with each taxon, the PD measure becomes the expected PD measure. In the Noah's Ark Problem (NAP) introduced by Weitzman (1998), these survival probabilities can be increased at some cost. The problem is to determine how best to allocate a limited amount of resources to maximize the expected PD of the considered species. It is easy to formulate the NAP as a (difficult) nonlinear 0-1 programming problem. The aim of this article is to show that a general version of the NAP (GNAP) can be solved simply and efficiently with any set of edge weights and any set of survival probabilities by using standard mixed-integer linear programming software. The crucial point to move from a nonlinear program in binary variables to a mixed-integer linear program, is to approximate the logarithmic function by the lower envelope of a set of tangents to the curve. Solving the obtained mixed-integer linear program provides not only a near-optimal solution but also an upper bound on the value of the optimal solution. We also applied this approach to a generalization of the nature reserve problem (GNRP) that consists of selecting a set of regions to be conserved so that the expected PD of the set of species present in these regions is maximized. In this case, the survival probabilities of different taxa are not independent of each other. Computational results are presented to illustrate potentialities of the approach. Near-optimal solutions with hypothetical phylogenetic trees comprising about 4000 taxa are obtained in a few seconds or minutes of computing time for the GNAP, and in

  1. Wireless device connection problems and design solutions

    Song, Ji-Won; Norman, Donald; Nam, Tek-Jin; Qin, Shengfeng


    Users, especially the non-expert users, commonly experience problems when connecting multiple devices with interoperability. While studies on multiple device connections are mostly concentrated on spontaneous device association techniques with a focus on security aspects, the research on user interaction for device connection is still limited. More research into understanding people is needed for designers to devise usable techniques. This research applies the Research-through-Design method and studies the non-expert users' interactions in establishing wireless connections between devices. The "Learning from Examples" concept is adopted to develop a study focus line by learning from the expert users' interaction with devices. This focus line is then used for guiding researchers to explore the non-expert users' difficulties at each stage of the focus line. Finally, the Research-through-Design approach is used to understand the users' difficulties, gain insights to design problems and suggest usable solutions. When connecting a device, the user is required to manage not only the device's functionality but also the interaction between devices. Based on learning from failures, an important insight is found that the existing design approach to improve single-device interaction issues, such as improvements to graphical user interfaces or computer guidance, cannot help users to handle problems between multiple devices. This study finally proposes a desirable user-device interaction in which images of two devices function together with a system image to provide the user with feedback on the status of the connection, which allows them to infer any required actions.

  2. Solute specific scaling of inorganic nitrogen and phosphorus uptake in streams

    R. O. Hall Jr.


    Full Text Available Stream ecosystem processes such as nutrient cycling may vary with stream position in the watershed. Using a scaling approach, we examined the relationship between stream size and nutrient uptake length, which represents the mean distance that a dissolved solute travels prior to removal from the water column. Ammonium uptake length increased proportionally with stream size measured as specific discharge (discharge/stream width with a scaling exponent = 1.01. In contrast, the scaling exponent for nitrate (NO3− was 1.19 and for soluble reactive phosphorus (SRP was 1.35, suggesting that uptake lengths for these nutrients increased more rapidly than increases in specific discharge. Additionally, the ratio of nitrogen (N uptake length to SRP uptake length declined with stream size; there was lower demand for SRP relative to N as stream size increased. Ammonium and NO3− uptake velocity positively related with stream metabolism, while SRP did not. Finally, we related the scaling of uptake length and specific discharge to that of stream length using Hack's law and downstream hydraulic geometry. Ammonium uptake length increased less than proportionally with distance from the headwaters, suggesting a strong role for larger streams and rivers in regulating nutrient transport.

  3. Solute transport processes in flow-event-driven stream-aquifer interaction

    Xie, Yueqing; Cook, Peter G.; Simmons, Craig T.


    The interaction between streams and groundwater controls key features of the stream hydrograph and chemograph. Since surface runoff is usually less saline than groundwater, flow events are usually accompanied by declines in stream salinity. In this paper, we use numerical modelling to show that, at any particular monitoring location: (i) the increase in stream stage associated with a flow event will precede the decrease in solute concentration (arrival time lag for solutes); and (ii) the decrease in stream stage following the flow peak will usually precede the subsequent return (increase) in solute concentration (return time lag). Both arrival time lag and return time lag increase with increasing wave duration. However, arrival time lag decreases with increasing wave amplitude, whereas return time lag increases. Furthermore, while arrival time lag is most sensitive to parameters that control river velocity (channel roughness and stream slope), return time lag is most sensitive to groundwater parameters (aquifer hydraulic conductivity, recharge rate, and dispersitivity). Additionally, the absolute magnitude of the decrease in river concentration is sensitive to both river and groundwater parameters. Our simulations also show that in-stream mixing is dominated by wave propagation and bank storage processes, and in-stream dispersion has a relatively minor effect on solute concentrations. This has important implications for spreading of contaminants released to streams. Our work also demonstrates that a high contribution of pre-event water (or groundwater) within the flow hydrograph can be caused by the combination of in-stream and bank storage exchange processes, and does not require transport of pre-event water through the catchment.

  4. Approaches to stream solute load estimation for solutes with varying dynamics from five diverse small watershed

    Aulenbach, Brent T.; Burns, Douglas A.; Shanley, James B.; Yanai, Ruth D.; Bae, Kikang; Wild, Adam; Yang, Yang; Yi, Dong


    Estimating streamwater solute loads is a central objective of many water-quality monitoring and research studies, as loads are used to compare with atmospheric inputs, to infer biogeochemical processes, and to assess whether water quality is improving or degrading. In this study, we evaluate loads and associated errors to determine the best load estimation technique among three methods (a period-weighted approach, the regression-model method, and the composite method) based on a solute's concentration dynamics and sampling frequency. We evaluated a broad range of varying concentration dynamics with stream flow and season using four dissolved solutes (sulfate, silica, nitrate, and dissolved organic carbon) at five diverse small watersheds (Sleepers River Research Watershed, VT; Hubbard Brook Experimental Forest, NH; Biscuit Brook Watershed, NY; Panola Mountain Research Watershed, GA; and Río Mameyes Watershed, PR) with fairly high-frequency sampling during a 10- to 11-yr period. Data sets with three different sampling frequencies were derived from the full data set at each site (weekly plus storm/snowmelt events, weekly, and monthly) and errors in loads were assessed for the study period, annually, and monthly. For solutes that had a moderate to strong concentration–discharge relation, the composite method performed best, unless the autocorrelation of the model residuals was <0.2, in which case the regression-model method was most appropriate. For solutes that had a nonexistent or weak concentration–discharge relation (modelR2 < about 0.3), the period-weighted approach was most appropriate. The lowest errors in loads were achieved for solutes with the strongest concentration–discharge relations. Sample and regression model diagnostics could be used to approximate overall accuracies and annual precisions. For the period-weighed approach, errors were lower when the variance in concentrations was lower, the degree of autocorrelation in the concentrations was

  5. Landmine research: technology solutions looking for problems

    Trevelyan, James P.


    The global landmine problem came to the attention of researchers in the mid 1990's and by 1997 several advanced and expensive sensor research programs had started. Yet, by the end of 2003, there is little sign of a major advance in the technology available to humanitarian demining programs. Given the motivation and dedication of researchers, public goodwill to support such programs, and substantial research resources devoted to the problem, it is worth asking why these programs do not seem to have had an impact on demining costs or casualty rates. Perhaps there are factors that have been overlooked. This paper reviews several research programs to gain a deeper understanding of the problem. A possible explanation is that researchers have accepted mistaken ideas on the nature of the landmine problems that need to be solved. The paper provides several examples where the realities of minefield conditions are quite different to what researchers have been led to believe. Another explanation may lie in the political and economic realities that drive the worldwide effort to eliminate landmines. Most of the resources devoted to landmine clearance programs come from humanitarian aid budgets: landmine affected countries often contribute only a small proportion because they have different priorities based on realistic risk-based assessment of needs and political views of local people. Some aid projects have been driven by the need to find a market for demining technologies rather than by user needs. Finally, there is a common misperception that costs in less developed countries are intrinsically low, reflecting low rates paid for almost all classes of skilled labour. When actual productivity is taken into account, real costs can be higher than industrialized countries. The costs of implementing technological solutions (even using simple technologies) are often significantly under-estimated. Some political decisions may have discouraged thorough investigation of cost

  6. A solution to the naturalness problem

    Fariborz, Amir H


    We present a solution to the naturalness problem of the electroweak scale based on a change of variable in the Fourier space of non supersymmetric nature that transforms a boson into a fermion and viceversa. This is exemplified for that part of the standard model Lagrangian that contains a Dirac fermion coupled with the Higgs field. The full Lagrangian which contains both the initial particles and the partners obtained through this method is invariant under the symmetry associated to this change of variables and is free of quadratic divergences to the scalar particles present in the Lagrangian. The partners appear mostly as "off-shell" states thus explaining their experimental absence at any particle accelerators.

  7. Problems and solutions in quantum chemistry and physics

    Johnson, Charles S


    Unusually varied problems, with detailed solutions, cover quantum mechanics, wave mechanics, angular momentum, molecular spectroscopy, scattering theory, more. 280 problems, plus 139 supplementary exercises.

  8. Anomalous solutions to the strong CP problem.

    Hook, Anson


    We present a new mechanism for solving the strong CP problem using a Z_{2} discrete symmetry and an anomalous U(1) symmetry. A Z_{2} symmetry is used so that two gauge groups have the same theta angle. An anomalous U(1) symmetry makes the difference between the two theta angles physical and the sum unphysical. Two models are presented where the anomalous symmetry manifests itself in the IR in different ways. In the first model, there are massless bifundamental quarks, a solution reminiscent of the massless up quark solution. In the IR of this model, the η^{'} boson relaxes the QCD theta angle to the difference between the two theta angles-in this case zero. In the second model, the anomalous U(1) symmetry is realized in the IR as a dynamically generated mass term that has exactly the phase needed to cancel the theta angle. Both of these models make the extremely concrete prediction that there exist new colored particles at the TeV scale.

  9. Transfer of Solutions to Conditional Probability Problems: Effects of Example Problem Format, Solution Format, and Problem Context

    Chow, Alan F.; Van Haneghan, James P.


    This study reports the results of a study examining how easily students are able to transfer frequency solutions to conditional probability problems to novel situations. University students studied either a problem solved using the traditional Bayes formula format or using a natural frequency (tree diagram) format. In addition, the example problem…

  10. Shock solution for quasilinear singularly perturbed Robin problem


    The shock solution for the quasilinear singularly perturbed Robin problem is considered. Under suitable conditions and using the theory of differential inequalities the existence and asymptotic behavior of the shock solution for the original boundary value problems are studied.

  11. Existence of Solution for Fractional Differential Problem with a Parameter

    Shi Ai-ling; Zhang Shu-qin


    We apply the method of lower and upper solutions combined with mono-tone iterations to fractional differential problem with a parameter. The existence of minimal and maximal solutions is proved for the fractional differential problem with a parameter.

  12. Education in Pakistan: Problems and their Solutions

    Khalid Rashid


    present situations. The interaction with the stakeholders may also help sort out the problems and give their possible solutions.

  13. The Streaming Complexity of Cycle Counting, Sorting by Reversals, and Other Problems

    Verbin, Elad; Yu, Wei


    In this paper we introduce a new technique for proving streaming lower bounds (and one-way communication lower bounds), by reductions from a problem called the Boolean Hidden Hypermatching problem (BHH). BHH is a gener- alization of the well-known Boolean Hidden Matching problem, which was used b...

  14. A 2D forward and inverse code for streaming potential problems

    Soueid Ahmed, A.; Jardani, A.; Revil, A.


    The self-potential method corresponds to the passive measurement of the electrical field in response to the occurrence of natural sources of current in the ground. One of these sources corresponds to the streaming current associated with the flow of the groundwater. We can therefore apply the self- potential method to recover non-intrusively some information regarding the groundwater flow. We first solve the forward problem starting with the solution of the groundwater flow problem, then computing the source current density, and finally solving a Poisson equation for the electrical potential. We use the finite-element method to solve the relevant partial differential equations. In order to reduce the number of (petrophysical) model parameters required to solve the forward problem, we introduced an effective charge density tensor of the pore water, which can be determined directly from the permeability tensor for neutral pore waters. The second aspect of our work concerns the inversion of the self-potential data using Tikhonov regularization with smoothness and weighting depth constraints. This approach accounts for the distribution of the electrical resistivity, which can be independently and approximately determined from electrical resistivity tomography. A numerical code, SP2DINV, has been implemented in Matlab to perform both the forward and inverse modeling. Three synthetic case studies are discussed.

  15. SP2DINV: A 2D forward and inverse code for streaming potential problems

    Soueid Ahmed, A.; Jardani, A.; Revil, A.; Dupont, J. P.


    The self-potential method corresponds to the passive measurement of the electrical field in response to the occurrence of natural sources of current in the ground. One of these sources corresponds to the streaming current associated with the flow of the ground water. We can therefore apply the self-potential method to recover non-intrusively some information regarding the ground water flow. We first solve the forward problem starting with the solution of the ground water flow problem, then computing the source current density, and finally solving a Poisson equation for the electrical potential. We use the finite-element method to solve the relevant partial differential equations. In order to reduce the number of (petrophysical) model parameters required to solve the forward problem, we introduced an effective charge density tensor of the pore water, which can be determined directly from the permeability tensor for neutral pore waters. The second aspect of our work concerns the inversion of the self-potential data using Tikhonov regularization with smoothness and weighting depth constraints. This approach accounts for the distribution of the electrical resistivity, which can be independently and approximately determined from electrical resistivity tomography. A numerical code, SP2DINV, has been implemented in Matlab to perform both the forward and inverse modeling. Three synthetic case studies are discussed.

  16. Hydro-abrasive erosion: Problems and solutions

    Winkler, K.


    The number of hydro power plants with hydro-abrasive erosion is increasing worldwide. An overall approach is needed to minimize the impact of this phenomenon. Already at the start of the planning phase an evaluation should be done to quantify the erosion and the impact on the operation. For this, the influencing parameters and their impact on the erosion have to be known. The necessary information for the evaluation comprises among others the future design, the particle parameters of the water, which will pass the turbine, and the power plant owner's framework for the future operation like availability or maximum allowable efficiency loss, before an overhaul needs to be done. Based on this evaluation of the erosion, an optimised solution can then be found, by analysing all measures in relation to investments, energy production and maintenance costs as decision parameters. Often a more erosion-resistant design, instead of choosing the turbine design with the highest efficiency, will lead to higher revenue. The paper will discuss the influencing parameters on hydro-abrasive erosion and the problems to acquire this information. There are different optimisation possibilities, which will be shown in different case studies. One key aspect to reduce the erosion and prolong the operation time of the components is to coat all relevant parts. But it is very important that this decision is taken early in the design stage, as the design has to be adapted to the requirements of the coating process. The quality of coatings and their impact on the operation will be discussed in detail in the paper as due to the non-availability of standards many questions arise in projects.

  17. Asymptotic traveling wave solution for a credit rating migration problem

    Liang, Jin; Wu, Yuan; Hu, Bei


    In this paper, an asymptotic traveling wave solution of a free boundary model for pricing a corporate bond with credit rating migration risk is studied. This is the first study to associate the asymptotic traveling wave solution to the credit rating migration problem. The pricing problem with credit rating migration risk is modeled by a free boundary problem. The existence, uniqueness and regularity of the solution are obtained. Under some condition, we proved that the solution of our credit rating problem is convergent to a traveling wave solution, which has an explicit form. Furthermore, numerical examples are presented.

  18. TA-designed vs. research-oriented problem solutions

    Lin, Shih-Yin; Mamudi, William; Henderson, Charles R; Yerushalmi, Edit


    In order to study graduate teaching assistants (TAs) beliefs and values about the design of instructor problem solutions, twenty-four TAs were provided with different solutions and asked to discuss their preferences for prominent solution features. TAs preferences for solution features were examined in light of the modeling of expert-like problem solving process as recommended in the literature. Results suggest that while many of the features TAs valued align with expert-like problem solving approaches, they noticed primarily "surface features" of solutions. Moreover, self-reported preferences did not match well with the solutions TAs wrote on their own.

  19. Geometric Series: A New Solution to the Dog Problem

    Dion, Peter; Ho, Anthony


    This article describes what is often referred to as the dog, beetle, mice, ant, or turtle problem. Solutions to this problem exist, some being variations of each other, which involve mathematics of a wide range of complexity. Herein, the authors describe the intuitive solution and the calculus solution and then offer a completely new solution…

  20. Boundary Value Problems and Approximate Solutions


    boundary value problems suggested by nonlinear diffusion process. .... According to VIM, a correction functional could be written as follows: (5.4) ... The Variational Iteration Method is remarkably effective for solving boundary value problems.

  1. General Problem Solving: Navy Requirements and Solutions.


    subjects’ ability to manipulate their environment. In one test, the subjects were asked to tell how to save a kitten stranded at the top of a tree. The...unstruc- - .tured design problem to a structured problem. "* We have to be careful not to introduce unnecessary constraints in a problem. This is the case

  2. Viscosity Solutions for the two-phase Stefan Problem

    Kim, Inwon C


    We introduce a notion of viscosity solutions for the two-phase Stefan problem, which incorporates possible existence of a mushy region generated by the initial data. We show that a comparison principle holds between viscosity solutions, and investigate the coincidence of the viscosity solutions and the weak solutions defined via integration by parts. In particular, in the absence of initial mushy region, viscosity solution is the unique weak solution with the same boundary data.

  3. On Alternative Optimal Solutions to Linear Fractional Optimization Problems



    The structure of the optimal solution set is derived for linear fractional optimization problems with the representation theorem of polyhedral sets.And the computational procedure in determining all optimal solutions is also given.

  4. Existence theorems of solution to variational inequality problems


    This paper introduces a new concept of exceptional family forvariational inequality problems with a general convex constrained set. By using this new concept, the authors establish a general sufficient condition for the existence of a solution to the problem. This condition is weaker than many known solution conditions and it is also necessary for pseudomonotone variational inequalities. Sufficient solution conditions for a class of nonlinear complementarity problems with P0 mappings are also obtained.

  5. The Median Solution of the Newsvendor Problem and Some Observations

    Sinha Pritibhushan


    Full Text Available We consider the median solution of the Newsvendor Problem. Some properties of such a solution are shown through a theoretical analysis and a numerical experiment. Sometimes, though not often, median solution may be better than solutions maximizing expected profit, or maximizing minimum possible, over distribution with the same average and standard deviation, expected profit, according to some criteria. We discuss the practical suitability of the objective function set and the solution derived, for the Newsvendor Problem, and other such random optimization problems.

  6. Pseudo almost periodic solutions to parabolic boundary value inverse problems


    We first define the pseudo almost periodic functions in a more general setting.Then we show the existence,uniqueness and stability of pseudo almost periodic solutions of parabolic inverse problems for a type of boundary value problems.

  7. DNA solution of the maximal clique problem.

    Ouyang, Q; Kaplan, P D; Liu, S; Libchaber, A


    The maximal clique problem has been solved by means of molecular biology techniques. A pool of DNA molecules corresponding to the total ensemble of six-vertex cliques was built, followed by a series of selection processes. The algorithm is highly parallel and has satisfactory fidelity. This work represents further evidence for the ability of DNA computing to solve NP-complete search problems.

  8. Solutions to selected exercise problems in quantum chemistry and spectroscopy

    Spanget-Larsen, Jens


    Suggested solutions to a number of problems from the collection "Exercise Problems in Quantum Chemistry and Spectroscopy", previously published on ResearchGate (DOI: 10.13140/RG.2.1.4024.8162).......Suggested solutions to a number of problems from the collection "Exercise Problems in Quantum Chemistry and Spectroscopy", previously published on ResearchGate (DOI: 10.13140/RG.2.1.4024.8162)....

  9. Solutions to selected exercise problems in quantum chemistry and spectroscopy

    Spanget-Larsen, Jens


    Suggested solutions to a number of problems from the collection "Exercise Problems in Quantum Chemistry and Spectroscopy", previously published on ResearchGate (DOI: 10.13140/RG.2.1.4024.8162).......Suggested solutions to a number of problems from the collection "Exercise Problems in Quantum Chemistry and Spectroscopy", previously published on ResearchGate (DOI: 10.13140/RG.2.1.4024.8162)....

  10. Biofilm growth in gravel bed streams controls solute residence time distributions

    Aubeneau, A. F.; Hanrahan, Brittany; Bolster, Diogo; Tank, Jennifer


    Streambed substrates harbor a rich biome responsible for biogeochemical processing in riverine waters. Beyond their biological role, the presence of benthic and hyporheic biofilms can play an important role in influencing large-scale transport of solutes, even for conservative tracers. As biofilms grow and accumulate biomass, they actively interact with and influence surface and subsurface flow patterns. To explore this effect, we conducted experiments at the Notre Dame Linked Ecosystems Experimental Facility in four outdoor streams, each with different gravel beds. Over the course of 20 weeks we conducted transport experiments in each of these streams and observed different patterns in breakthrough curves as biofilms grew on the substrate. Biofilms played a major role in shaping the observed conservative transport patterns. Overall, while the presence of biofilms led to a decreased exchange rate between the fast (mobile) and slow (immobile) parts of the flow domain, water that was exchanged tended to be stored in the slow regions for longer times once biofilms had established. More specifically, we observed enhanced longitudinal dispersion in breakthrough curves as well as broader residence time distributions when biofilms were present. Biofilm colonization over time homogenized transport patterns across the four streams that were originally very distinct. These results indicate that stream biofilms exert a strong control on conservative solute transport in streams, a role that to date has not received enough attention.

  11. Solute and sediment export from Amazon forest and soybean headwater streams.

    Riskin, Shelby H; Neill, Christopher; Jankowski, KathiJo; Krusche, Alex V; McHorney, Richard; Elsenbeer, Helmut; Macedo, Marcia N; Nunes, Darlisson; Porder, Stephen


    Intensive cropland agriculture commonly increases streamwater solute concentrations and export from small watersheds. In recent decades, the lowland tropics have become the world's largest and most important region of cropland expansion. Although the effects of intensive cropland agriculture on streamwater chemistry and watershed export have been widely studied in temperate regions, their effects in tropical regions are poorly understood. We sampled seven headwater streams draining watersheds in forest (n = 3) or soybeans (n = 4) to examine the effects of soybean cropping on stream solute concentrations and watershed export in a region of rapid soybean expansion in the Brazilian state of Mato Grosso. We measured stream flows and concentrations of NO3(-) , PO4(3-) , SO4(2-) , Cl(-) , NH4(+) , Ca(2+) , Mg(2+) , Na(+) , K(+) , Al(3+) , Fe(3+) , and dissolved organic carbon (DOC) biweekly to monthly to determine solute export. We also measured stormflows and stormflow solute concentrations in a subset of watersheds (two forest, two soybean) during two/three storms, and solutes and δ(18) O in groundwater, rainwater, and throughfall to characterize watershed flowpaths. Concentrations of all solutes except K(+) varied seasonally in streamwater, but only Fe(3+) concentrations differed between land uses. The highest streamwater and rainwater solute concentrations occurred during the peak season of wildfires in Mato Grosso, suggesting that regional changes in atmospheric composition and deposition influence seasonal stream solute concentrations. Despite no concentration differences between forest and soybean land uses, annual export of NH4(+) , PO4(3-) , Ca(2+) , Fe(3+) , Na(+) , SO4(2-) , DOC, and TSS were significantly higher from soybean than forest watersheds (5.6-fold mean increase). This increase largely reflected a 4.3-fold increase in water export from soybean watersheds. Despite this increase, total solute export per unit watershed area (i.e., yield) remained

  12. Investment attractiveness of Ukraine: problems and solutions

    Onishchenko Irina


    Full Text Available The article describes basic questions of the investment climate and investment attractiveness of Ukraine. Investment Attractiveness Index is analyzed by the methodology of European Business Association. The main advantages of Ukraine that attract foreign investors are revised. The article applies the comprehensive approach to study the problems hindering the increase of investment attractiveness of Ukraine. It determines the ways of solving the problems associated with deterring investment development.

  13. Hibernate Recipes A Problem-Solution Approach

    Mak, Gary


    Hibernate continues to be the most popular out-of-the-box framework solution for Java Persistence and data/database accessibility techniques and patterns. It is used for e-commerce-based web applications as well as heavy-duty transactional systems for the enterprise. Gary Mak, the author of the best-selling Spring Recipes, now brings you Hibernate Recipes. This book contains a collection of code recipes and templates for learning and building Hibernate solutions for you and your clients. This book is your pragmatic day-to-day reference and guide for doing all things involving Hibernate. There

  14. Positive solutions of three-point boundary value problems

    MIAO Ye-hong; ZHANG Ji-hui


    In this paper,we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian.We then study existence of solutions when the problems are in resonance cases.The proposed approach is based on the Krasnoselskii's fixed point theorem and the coincidence degree.

  15. Mass transfer of a neutral solute in porous microchannel under streaming potential.

    Mondal, Sourav; De, Sirshendu


    The mass transport of a neutral solute in a porous wall, under the influence of streaming field, has been analyzed in this study. The effect of the induced streaming field on the electroviscous effect of the fluid for different flow geometries has been suitably quantified. The overall electroosmotic velocity profile and expression for streaming field have been obtained analytically using the Debye-Huckel approximation, and subsequently used in the analysis for the mass transport. The analysis shows that as the solution Debye length increases, the strength of the streaming field and, consequently, the electroviscous effect diminishes. The species transport equation has been coupled with Darcy's law for quantification of the permeation rate across the porous wall. The concentration profile inside the mass transfer boundary layer has been solved using the similarity transformation, and the Sherwood number has been calculated from the definition. In this study, the variation of the permeation rate and solute permeate concentration has been with the surface potential, wall retention factor and osmotic pressure coefficient has been demonstrated for both the circular as well as rectangular channel cross-section.

  16. Fifty challenging problems in probability with solutions

    Mosteller, Frederick


    Can you solve the problem of ""The Unfair Subway""? Marvin gets off work at random times between 3 and 5 p.m. His mother lives uptown, his girlfriend downtown. He takes the first subway that comes in either direction and eats dinner with the one he is delivered to. His mother complains that he never comes to see her, but he says she has a 50-50 chance. He has had dinner with her twice in the last 20 working days. Explain. Marvin's adventures in probability are one of the fifty intriguing puzzles that illustrate both elementary ad advanced aspects of probability, each problem designed to chall

  17. Internal Performance Measurement Systems: Problems and Solutions

    Jakobsen, Morten; Mitchell, Falconer; Nørreklit, Hanne


    . The analysis uses and extends N rreklit's (2000) critique of the BSC by applying the concepts developed therein to contemporary research on the BSC and to the development of practice in performance measurement. The analysis is of relevance for many companies in the Asia-Pacific area as an increasing numbers......This article pursues two aims: to identify problems and dangers related to the operational use of internal performance measurement systems of the Balanced Scorecard (BSC) type and to provide some guidance on how performance measurement systems may be designed to overcome these problems...

  18. Iterative solution of the reduced eigenvalue problem

    Sauer, G. (Technischer Ueberwachungs-Verein Bayern e.V., Muenchen (Germany, F.R.))


    The Guyan method of reducing the stiffness and mass matrices of large linear structures introduces errors in the reduced mass matrix. These errors cannot be completely avoided even if the analysis coordinates are chosen optimally. However, they can be elimiated by iterating on the eigenvectors found from the Guyan reduced matrices. The necessary iteration steps follow directly from the eigenvalue problem. The resulting iteration procedures are presented and applied to two test problems showing that the iterations enable the exact eigensolutions to be extracted. All errors from the Guyan reduced matrices are removed or substantially decreased. (orig.).

  19. Urban management in China: Problems and solutions

    YE Jian-ping; ZHANG Yue-song; LI Gui-jun


    This essay describes the general situation of the cities in China and analyzes the problems appearing in planning, land use and government behavior in the process of urban management. The key to solving the problems existing in urban management and realizing the delicate growth of the cities in China, in terms of urban economics, urban management theory, public administration and administrative management, lies in standardizing government behavior, coordinating the relationships between the government and the market, improving the planning system, scientifically compiling planning, strengthening the market mechanism and encouraging public participation.

  20. Solution of a Complex Least Squares Problem with Constrained Phase.

    Bydder, Mark


    The least squares solution of a complex linear equation is in general a complex vector with independent real and imaginary parts. In certain applications in magnetic resonance imaging, a solution is desired such that each element has the same phase. A direct method for obtaining the least squares solution to the phase constrained problem is described.

  1. Problem Solvers: Solutions--Playing Basketball

    Smith, Jeffrey


    In this article, fourth grade Upper Allen Elementary School (Mechanicsburg, Pennsylvania) teacher Jeffrey Smith describes his exploration of the Playing Basketball activity. Herein he describes how he found the problem to be an effective way to review concepts associated with the measurement of elapsed time with his students. Additionally, it…

  2. Problem Solvers: Solutions--The Inaugural Address

    Dause, Emily


    Fourth graders in Miss Dause's and Mrs. Hicks's mathematics classes at South Mountain Elementary School in Dillsburg, Pennsylvania, worked with the data from the Inauagural Address problem that was previously published published in the February 2013 issue of "Teaching Children Mathematics". This activity allowed students to showcase…

  3. Bayesian solutions for food science problems?

    Boekel, van M.A.J.S.


    This paper starts with an overview of some typical food-science problems. In view of the development of safe and healthy food, the use of mathematical models in food science is much needed and the use of statistics is therefore indispensable. Because of the biological variability in the raw material

  4. Can False Memories Prime Problem Solutions?

    Howe, Mark L.; Garner, Sarah R.; Dewhurst, Stephen A.; Ball, Linden J.


    Previous research has suggested that false memories can prime performance on related implicit and explicit memory tasks. The present research examined whether false memories can also be used to prime higher order cognitive processes, namely, insight-based problem solving. Participants were asked to solve a number of compound remote associate task…

  5. Problem Solvers: Solutions--Playing Basketball

    Smith, Jeffrey


    In this article, fourth grade Upper Allen Elementary School (Mechanicsburg, Pennsylvania) teacher Jeffrey Smith describes his exploration of the Playing Basketball activity. Herein he describes how he found the problem to be an effective way to review concepts associated with the measurement of elapsed time with his students. Additionally, it…

  6. English Preservice Teaching: Problems and Suggested Solutions

    Naeem, Marwa Ahmed Refat


    The present study investigated the problems faced by Egyptian EFL prospective teachers during their first encounter with preservice teaching. The sample for the study included 135 prospective EFL teachers trained in five preparatory (middle) schools in Kafr El-Sheikh city, Egypt. At the end of their first year training course, the prospective…

  7. Solutions to selected problems from the physics of radiology

    Johns, Harold


    This book serves as a practical guide to solving problems presented in THE PHYSICS OF RADIOLOGY, Fourth Edition. The authors contend that one does not really understand physics unless one can use it to solve problems and they have encouraged classroom problem-solving and discussion of solutions. This volume enhances that process. Approximately half of the problems found at the end of each chapter in the text have been selected with reasonable solutions provided. Solutions include, where appropriate, discussion of assumptions that may have to be made, and where the relevant formulae and data ar

  8. Variance reduction techniques for 14 MeV neutron streaming problem in rectangular annular bent duct

    Ueki, Kotaro [Ship Research Inst., Mitaka, Tokyo (Japan)


    Monte Carlo method is the powerful technique for solving wide range of radiation transport problems. Its features are that it can solve the Boltzmann`s transport equation almost without approximation, and that the complexity of the systems to be treated rarely becomes a problem. However, the Monte Carlo calculation is always accompanied by statistical errors called variance. In shielding calculation, standard deviation or fractional standard deviation (FSD) is used frequently. The expression of the FSD is shown. Radiation shielding problems are roughly divided into transmission through deep layer and streaming problem. In the streaming problem, the large difference in the weight depending on the history of particles makes the FSD of Monte Carlo calculation worse. The streaming experiment in the 14 MeV neutron rectangular annular bent duct, which is the typical streaming bench mark experiment carried out of the OKTAVIAN of Osaka University, was analyzed by MCNP 4B, and the reduction of variance or FSD was attempted. The experimental system is shown. The analysis model by MCNP 4B, the input data and the results of analysis are reported, and the comparison with the experimental results was examined. (K.I.)

  9. Multiple optimal solutions to a sort of nonlinear optimization problem

    Xue Shengjia


    The optimization problem is considered in which the objective function is pseudolinear(both pseudoconvex and pseudoconcave) and the constraints are linear. The general expression for the optimal solutions to the problem is derived with the representation theorem of polyhedral sets, and the uniqueness condition of the optimal solution and the computational procedures to determine all optimal solutions ( ifthe uniqueness condition is not satisfied ) are provided. Finally, an illustrative example is also given.



    By the Schauder fixed point theory,this paper establishes the existence of positive solutions to a(k,n k) m-point boundary value problem.We show that there exists a positive constant b such that the problem has at least one positive solution when the homogeneous boundary parameter is smaller than b,and no positive solution when this parameter is greater than b.

  11. Checking for Optimal Solutions in Some NP-Complete Problems

    Bauer, Michel; Orland, Henri


    For some weighted NP-complete problems, checking whether a proposed solution is optimal is a nontrivial task. Such is the case for the traveling salesman problem, or the spin-glass problem in three dimensions. In this Letter, we consider the weighted tripartite matching problem, a well known NP-complete problem. We write mean-field finite temperature equations for this model and derive their zero temperature limit. We show that any solution of the zero temperature equations provides an exact absolute ground state of the system. As a consequence, we propose a criterion which can be checked in polynomial time, and such that given a putative optimal solution, if the criterion is satisfied, then the solution is indeed optimal. This criterion is generalized to a class of variants of the multiple traveling salesmen problems.

  12. Interval analysis for Certified Numerical Solution of Problems in Robotics

    Merlet, Jean-Pierre


    International audience; Interval analysis is a relatively new mathematical tool that allows one to deal with problems that may have to be solved numerically with a computer. Examples of such problems are system solving and global optimization but numerous other problems may be addressed as well. This approach has the following general advantages: 1 it allows to find solutions of a problem only within some finite domain which make sense as soon as the unknowns in the problem are physical param...

  13. Problems in quantum mechanics with solutions

    d'Emilio, Emilio


    This second edition of an extremely well-received book presents more than 250 nonrelativistic quantum mechanics problems of varying difficulty with the aim of providing students didactic material of proven value, allowing them to test their comprehension and mastery of each subject. The coverage is extremely broad, from themes related to the crisis of classical physics through achievements within the framework of modern atomic physics to lively debated, intriguing aspects relating to, for example, the EPR paradox, the Aharonov-Bohm effect, and quantum teleportation. Compared with the first edition, a variety of improvements have been made and additional topics of interest included, especially focusing on elementary potential scattering. The problems themselves range from standard and straightforward ones to those that are complex but can be considered essential because they address questions of outstanding importance or aspects typically overlooked in primers. The book offers students both an excellent tool f...

  14. Ergonomics problems and solutions in biotechnology laboratories

    Coward, T.W.; Stengel, J.W.; Fellingham-Gilbert, P.


    The multi-functional successful ergonomics program currently implemented at Lawrence Livermore National Laboratory (LLNL) will be presented with special emphasis on recent findings in the Biotechnology laboratory environment. In addition to a discussion of more traditional computer-related repetitive stress injuries and associated statistics, the presentation will cover identification of ergonomic problems in laboratory functions such as pipetting, radiation shielding, and microscope work. Techniques to alleviate symptoms and prevent future injuries will be presented.

  15. Computational solution of atmospheric chemistry problems

    Jafri, J.; Ake, R. L.


    Extensive studies were performed on problems of interest in atmospheric chemistry. In addition to several minor projects, four major projects were performed and described (theoretical studies of ground and low-lying excited states of ClO2; ground and excited state potential energy surfaces of the methyl peroxy radical; electronic states ot the FO radical; and theoretical studies S02 (H2O) (sub n)).

  16. Medical Wearable Technologies: Applications, Problems and Solutions

    Bostanci, Erkan


    The focus of this paper is on wearable technologies which are increasingly being employed in the medical field. From smart watches to smart glasses, from electronic textile to data gloves; several gadgets are playing important roles in diagnosis and treatment of various medical conditions. The threats posed by these technologies are another matter of concern that must be seriously taken into account. Numerous threats ranging from data privacy to big data problems are facing us as adverse effe...

  17. Explicit Solutions of Moment Problems 1.


    well known,(see e.g. Levin and Miljutin (1978), Kellerer (1984), Kemperman (1983), Haneveld (1985), Rischendorf (1985), Rachev (1984) and references...the marginal problem for different spaces U and criterion functions c are given by Levin and Miljutin (1978), Kellerer (1984), Haneveld (1985...Krein (1962), Karlin and Studden (1966), Hoeffding (1955), Hoeffding and Shrikhande (1956), Basu and Simons (1983), Kemperman (1972,1983), Haneveld (1985

  18. Response of non-added solutes during nutrient addition experiments in streams

    Rodriguez-Cardona, B.; Wymore, A.; Koenig, L.; Coble, A. A.; McDowell, W. H.


    Nutrient addition experiments, such as Tracer Additions for Spiraling Curve Characterization (TASCC), have become widely popular as a means to study nutrient uptake dynamics in stream ecosystems. However, the impact of these additions on ambient concentrations of non-added solutes is often overlooked. TASCC addition experiments are ideal for assessing interactions among solutes because it allows for the characterization of multiple solute concentrations across a broad range of added nutrient concentrations. TASCC additions also require the addition of a conservative tracer (NaCl) to track changes in conductivity during the experimental manipulation. Despite its use as a conservative tracer, chloride (Cl) and its associated sodium (Na) might change the concentrations of other ions and non-added nutrients through ion exchange or other processes. Similarly, additions of biologically active solutes might change the concentrations of other non-added solutes. These methodological issues in nutrient addition experiments have been poorly addressed in the literature. Here we examine the response of non-added solutes to pulse additions (i.e. TASCC) of NaCl plus nitrate (NO3-), ammonium, and phosphate across biomes including temperate and tropical forests, and arctic taiga. Preliminary results demonstrate that non-added solutes respond to changes in the concentration of these added nutrients. For example, concentrations of dissolved organic nitrogen (DON) in suburban headwater streams of New Hampshire both increase and decrease in response to NO3- additions, apparently due to biotic processes. Similarly, cations such as potassium, magnesium, and calcium also increase during TASCC experiments, likely due to cation exchange processes associated with Na addition. The response of non-added solutes to short-term pulses of added nutrients and tracers needs to be carefully assessed to ensure that nutrient uptake metrics are accurate, and to detect biotic interactions that may

  19. Simple Solutions for Space Station Audio Problems

    Wood, Eric


    Throughout this summer, a number of different projects were supported relating to various NASA programs, including the International Space Station (ISS) and Orion. The primary project that was worked on was designing and testing an acoustic diverter which could be used on the ISS to increase sound pressure levels in Node 1, a module that does not have any Audio Terminal Units (ATUs) inside it. This acoustic diverter is not intended to be a permanent solution to providing audio to Node 1; it is simply intended to improve conditions while more permanent solutions are under development. One of the most exciting aspects of this project is that the acoustic diverter is designed to be 3D printed on the ISS, using the 3D printer that was set up earlier this year. Because of this, no new hardware needs to be sent up to the station, and no extensive hardware testing needs to be performed on the ground before sending it to the station. Instead, the 3D part file can simply be uploaded to the station's 3D printer, where the diverter will be made.

  20. Surface integrals approach to solution of some free boundary problems

    Igor Malyshev


    Full Text Available Inverse problems in which it is required to determine the coefficients of an equation belong to the important class of ill-posed problems. Among these, of increasing significance, are problems with free boundaries. They can be found in a wide range of disciplines including medicine, materials engineering, control theory, etc. We apply the integral equations techniques, typical for parabolic inverse problems, to the solution of a generalized Stefan problem. The regularization of the corresponding system of nonlinear integral Volterra equations, as well as local existence, uniqueness, continuation of its solution, and several numerical experiments are discussed.

  1. The Uniqueness of Optimal Solution for Linear Programming Problem

    QuanlingWei; HongYan; JunWang


    This paper investigates an old problem in operations research, the uniqueness of the optimal solution to a linear programming problem. We discuss the problem on a general polyhedron, give some equivalent conditions for uniqueness testing. In addition, we discuss the implementation issues for linear programming based decision making procedures,which motivated this research.


    Oleksandr V. Spivakovskyi


    Full Text Available The paper analyzes the main problems and development of ICT infrastructure of a higher education establishment. The influence of the University’s IT development on its ratings is studied. There are four variants of ICT infrastructure development of the University according to the administrative division of its IT departments and the main structural elements of the system “University Governance -n governing and IT maintaining departments”, their activity direction and forms are determined. In addition, the main components of information and communication pedagogical environment of the University and ICT of administrative direction as the main components of ICT university infrastructure are described and determined.

  3. Using Text Mining to Uncover Students' Technology-Related Problems in Live Video Streaming

    Abdous, M'hammed; He, Wu


    Because of their capacity to sift through large amounts of data, text mining and data mining are enabling higher education institutions to reveal valuable patterns in students' learning behaviours without having to resort to traditional survey methods. In an effort to uncover live video streaming (LVS) students' technology related-problems and to…

  4. Using Text Mining to Uncover Students' Technology-Related Problems in Live Video Streaming

    Abdous, M'hammed; He, Wu


    Because of their capacity to sift through large amounts of data, text mining and data mining are enabling higher education institutions to reveal valuable patterns in students' learning behaviours without having to resort to traditional survey methods. In an effort to uncover live video streaming (LVS) students' technology related-problems and to…

  5. Regularity of solutions of obstacle problems


    LetΩbe a bounded domain ofRnand letDbe aclosedsubset ofΩ.ForΨ∈W1,2(Ω)suchthatΨ0onΩ[1-2],we setKΨ={w∈W01,2(Ω)|wΨonDinthesense ofW1,2(Ω)}.Ifaij(x)=aji(x)(i,j=1,2,…,n)∈L∞(Ω)andλ|ξ|2 aij(x)ξiξj,x∈Ω,ξ∈Rn,(1.1)The obstacle problems are to find a functionu∈KΨwhich mini mizesj(v)=∫ΩaijivjvdxoverKΨ.Main resultsFor the obstacle problems,the following results arewell known,whose proof can be foundin[3]and[4].Lemma 1.1(i)There exists a uniqueΓΨ∈KΨsuchthat∫ΩaijiΓΨjΓΨdx=wi∈nfK∫ΨΩaijiwjwdx.(ii)There exists a unique...

  6. Safe bicycling – Problems and solutions

    Grecka M.


    Full Text Available Herewith a popularity of bicycling, various safety problems of cyclists are researched. Studies are connected with infrastructure, riding culture, choice of cyclist's suit and riding equipment. Overall, 382 respondents (159 cyclists, 119 drivers, 104 pedestrians were involved in the survey. The road participants' mutual communication problems in the traffic and opportunities of solving them were clarified. Most of cyclists wear comfortable daily or sporty clothing with reflective elements, and in their opinion, clothing with light emissive elements must be like daily clothing. The drivers could better notice cyclists, if they wear brightly colored suit with light emissive and reflective elements, but pedestrians – if cyclists use warning sound signals. The opinions of road participants about the placement of light emissive and reflective elements in cyclist's clothing were clarified. The prototype of cycling belt (Fig. 1e has been drawn up with LED stop signals, which are activated by the accelerometer placed in the central back pocket. The results of approbation have shown that the sensor does not provide the proper functioning of signals, due to a high level of riding movements. Using Motion Capture technology and bicycle exercise equipment, the research of oscillation of anthropometric points on the back has been carried out. The accelerometer should be placed between scapulae to design the cycling jacket.

  7. Food sustainability: problems, perspectives and solutions.

    Garnett, Tara


    The global food system makes a significant contribution to climate changing greenhouse gas emissions with all stages in the supply chain, from agricultural production through processing, distribution, retailing, home food preparation and waste, playing a part. It also gives rise to other major environmental impacts, including biodiversity loss and water extraction and pollution. Policy makers are increasingly aware of the need to address these concerns, but at the same time they are faced with a growing burden of food security and nutrition-related problems, and tasked with ensuring that there is enough food to meet the needs of a growing global population. In short, more people need to be fed better, with less environmental impact. How might this be achieved? Broadly, three main 'takes' or perspectives, on the issues and their interactions, appear to be emerging. Depending on one's view point, the problem can be conceptualised as a production challenge, in which case there is a need to change how food is produced by improving the unit efficiency of food production; a consumption challenge, which requires changes to the dietary drivers that determine food production; or a socio-economic challenge, which requires changes in how the food system is governed. This paper considers these perspectives in turn, their implications for nutrition and climate change, and their strengths and weaknesses. Finally, an argument is made for a reorientation of policy thinking which uses the insights provided by all three perspectives, rather than, as is the situation today, privileging one over the other.

  8. Antibacterial resistance: Current problems and possible solutions

    Sharma Rashmi


    Full Text Available Antimicrobial resistance is a natural biological phenomenon of response of microbes to the selective pressure of an antimicrobial drug. Resistance may be inherent, which explains the phenomenon of opportunistic infection or acquired. Concern about the resistance increased in the late 1990′s and since then, many governmental and agency reports have been published regarding the agricultural use of antibacterials, advising less use of antibacterials, appropriate choice of antibacterials and regimens, prevention of cross-infection and development of new antibacterials. The emergence of multidrug resistant strains of Gram-negative bacteria (Pseudomonas, Klebsiella, Enterobacter, Acinetobacter, Salmonella species and Gram-positve organisms (Staphylococcus, Enterococcus, Streptococcus species is the more worrisome in the present therapeutic scenario. Multidrug - resistant tuberculosis is another serious public health problems. Resistance to some agents can be overcome by modifying the dosage regimens (e.g., using high-dose therapy or inhibiting the resistance mechanism (e.g., beta-lactamase inhibitors, whereas other mechanisms of resistance can only be overcome by using an agent from a different class. It is urgently required to ban the sale of antibiotics without prescription, to use antibiotics more judiciously in hospitals by intensive teaching of the principles of the use of antibiotics and to establish better control measures for nosocomial infections. Thus, it is highly recommended that practicing physicians should become aware of the magnitude of existing problem of antibacterial resistance and help in fighting this deadly threat by rational prescribing.

  9. Public problems: Still waiting on the marketplace for solutions

    Gover, J. [Sandia National Labs., Albuquerque, NM (United States); Carayannis, E. [George Washington Univ., Washington, DC (United States); Huray, P.


    This report addresses the need for government sponsored R and D to address real public problems. The motivation is that a public benefit of the money spent must be demonstrated. The areas identified as not having appropriate attention resulting in unmet public needs include healthcare cost, cost and benefits of regulations, infrastructure problems, defense spending misaligned with foreign policy objectives, the crime problem, energy impact on the environment, the education problem, low productivity growth industry sectors, the income distribution problem, the aging problem, the propagation of disease and policy changes needed to address the solution of these problems.

  10. Some Standard model problems and possible solutions

    Barranco, J.


    Three problems of the standard model of elementary particles are studied from a phenomenological approach. (i) It is shown that the Dirac or the Majorana nature of the neutrino can be studied by looking for differences in the v-electron scattering if the polarization of the neutrino is considered. (ii) The absolute scale of the neutrino mass can be set if a four zero mass matrix texture is considered for the leptons. It is found that m ν3 ∼⃒ 0.05 eV. (iii) It is shown that it is possible -within a certain class of two Higgs model extensions of the standard model- to have a cancelation of the quadratic divergences to the mass of physical Higgs boson.

  11. The Solution to Waring's Problem for Monomials

    Carlini, Enrico; Geramita, Anthony V


    In the polynomial ring $T=k[y_1,...,y_n]$, with $n>1$, we bound the multiplicity of homogeneous radical ideals $I\\subset (y_1^{a_1},...,y_n^{a_n})$ such that $T/I$ is a graded $k$-algebra with Krull dimension one. As a consequence we solve the Waring Problem for all monomials, i.e. we compute the minimal number of linear forms needed to write a monomial as a sum of powers of these linear forms. Moreover, we give an explicit description of a sum of powers decomposition for monomials. We also produce new bounds for the Waring rank of polynomials which are a sum of pairwise coprime monomials.

  12. [Reprogramming of somatic cells. Problems and solutions].

    Schneider, T A; Fishman, V S; Liskovykh, M A; Ponamartsev, S V; Serov, O L; Tomilin, A N; Alenina, N


    An adult mammal is composed of more than 200 different types of specialized somatic cells whose differentiated state remains stable over the life of the organism. For a long time it was believed that the differentiation process is irreversible, and the transition between the two types of specialized cells is impossible. The possibility of direct conversion of one differentiated cell type to another was first shown in the 80s of the last century in experiments on the conversion of fibroblasts into myoblasts by ectopic expression of the transcription factor MyoD. Surprisingly, this technology has remained unclaimed in cell biology for a long time. Interest in it revived after 200 thanks to the research of Novel Prize winner Shinya Yamanaka who has shown that a small set of transcription factors (Oct4, Sox2, Klf4 and c-Myc) is capable of restoring pluripotency in somatic cells which they lost in the process of differentiation. In 2010, using a similar strategy and the tissue-specific transcription factors Vierbuchen and coauthors showed the possibility of direct conversion of fibroblasts into neurons, i. e. the possibility of transdifferentiation of one type of somatic cells in the other. The works of these authoras were a breakthrough in the field of cell biology and gave a powerful impulse to the development of cell technologies for the needs of regenerative medicine. The present review discusses the main historical discoveries that preceded this work, evaluates the status of the problem and the progress in the development of methods for reprogramming at the moment, describes the main approaches to solving the problems of reprogramming of somatic cells into neuronal, and briefly discusses the prospect of application of reprogramming and transdifferentiation of cells for such important application areas as regenerative medicine, cell replacement therapy and drug screening.

  13. STREAM

    Godsk, Mikkel

    This paper presents a flexible model, ‘STREAM’, for transforming higher science education into blended and online learning. The model is inspired by ideas of active and collaborative learning and builds on feedback strategies well-known from Just-in-Time Teaching, Flipped Classroom, and Peer...... Instruction. The aim of the model is to provide both a concrete and comprehensible design toolkit for adopting and implementing educational technologies in higher science teaching practice and at the same time comply with diverse ambitions. As opposed to the above-mentioned feedback strategies, the STREAM...

  14. Silverlight 2 Recipes A Problem-solution Approach

    Ghosh, Cameron


    Microsoft .NET Architect Evangelist, Jit Ghosh, presents a practical companion guide to developing rich, interactive web applications with Silverlight 2. Common problems, issues, and every--day scenarios are tackled with a detailed discussion of the solution and ready--made code recipes that will save you hours of coding time. The recipes included in Silverlight 2 Recipes: A Problem-Solution Approach have been carefully selected and tested with the professional developer in mind. You'll find clearly and succinctly stated problems, well--architected solutions, and ample discussion of the code a

  15. [Typical problems in pediatric emergencies: Possible solutions].

    Heimberg, E; Heinzel, O; Hoffmann, F


    Pediatric emergencies are rare and challenging for health care providers, parents, and patients. The purpose of this article is to highlight typical difficulties in the treatment of pediatric patients and to discuss potential solutions. This article is based on a selective literature search using PubMed and the experience of the authors in the field of simulation and pediatric emergencies. Inexperience with pediatric emergencies, uncertainty in technical skills, in the usage of pediatric equipment and in medication dosage as well as parental presence foster the perception of stress and potentially compromise the success of patient care. Beside implementation of simplified technical skill devices (e.g., intraosseous vascular access system, supraglottic airway devices, and alternative approaches for drug administration), there have been many efforts in recent years to improve patient safety. Tools for estimating body weight and precalculated drug-dosing charts have been implemented as well as standardized courses for guidelines, technical skills, and team-related skills have been established. To improve patient safety, regular training and implementation of a sustainable safety culture are mandatory.

  16. Numerical solution of control problems governed by nonlinear differential equations

    Heinkenschloss, M. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)


    In this presentation the author investigates an iterative method for the solution of optimal control problems. These problems are formulated as constrained optimization problems with constraints arising from the state equation and in the form of bound constraints on the control. The method for the solution of these problems uses the special structure of the problem arising from the bound constraint and the state equation. It is derived from SQP methods and projected Newton methods and combines the advantages of both methods. The bound constraint is satisfied by all iterates using a projection, the nonlinear state equation is satisfied in the limit. Only a linearized state equation has to be solved in every iteration. The solution of the linearized problems are done using multilevel methods and GMRES.

  17. Problems and agricultural solutions in olive groves

    Lozano-García, Beatriz; Parras-Alcántara, Luis


    The most important and extensive crops in the Mediterranean area are olive groves. Within the last 50 years, the surface occupied by olive groves has progressively increased in Spain including more complex topographies, poorer soils and worse climatic conditions. This situation has caused serious problems based on the losses of soil, nutrients and soil quality among others (Lozano-García and Parras-Alcántara, 2014). Therefore, alternative practices that avoid soil erosion and soil degradation must be considered. As a consequence, farmers together with scientist are innovating by the development of different practices in olive groves in order to avoid these problems and to improve soil conditions. There is a huge range of new practices. Some of them are: i. alternative management techniques such as organic farming, no tillage and minimum tillage. These techniques have a positive impact in soils (Parras-Alcántara and Lozano-García, 2014; Fernández-Romero et al., 2016). ii. the addition of different substances on the soil. For example, oil mill by-products that are thus potentially useful as soil amendments since they are effective sources of organic matter and nitrogen, improve soil quality and alleviate the environmental and agronomic limitations of Mediterranean agricultural soils, even those under using conventional tillage (Lozano-García et al., 2011; Lozano-García and Parras-Alcántara, 2013). iii. the use of covers as secondary crops inside the olive grove. These offer secondary benefits derived from alternative crops and soil protection due to fact that in olive groves the main problem is the high quantity of bare surface. With this contribution we want to show the current situation in olive groves and how better results could be obtained when both trustworthy information is available and farmers and scientist work together. REFERENCES Fernández-Romero, M.L., Parras-Alcántara, L., Lozano-García, B., Clark, J.M., Collins, C.D. 2016. Soil quality

  18. Organ shortage crisis: problems and possible solutions.

    Abouna, G M


    The demand for organ transplantation has rapidly increased all over the world during the past decade due to the increased incidence of vital organ failure, the rising success and greater improvement in posttransplant outcome. However, the unavailability of adequate organs for transplantation to meet the existing demand has resulted in major organ shortage crises. As a result there has been a major increase in the number of patients on transplant waiting lists as well as in the number of patients dying while on the waiting list. In the United States, for example, the number of patients on the waiting list in the year 2006 had risen to over 95,000, while the number of patient deaths was over 6,300. This organ shortage crisis has deprived thousands of patients of a new and better quality of life and has caused a substantial increase in the cost of alternative medical care such as dialysis. There are several procedures and pathways which have been shown to provide practical and effective solutions to this crisis. These include implementation of appropriate educational programs for the public and hospital staff regarding the need and benefits of organ donation, the appropriate utilization of marginal (extended criteria donors), acceptance of paired organ donation, the acceptance of the concept of "presumed consent," implementation of a system of "rewarded gifting" for the family of the diseased donor and also for the living donor, developing an altruistic system of donation from a living donor to an unknown recipient, and accepting the concept of a controlled system of financial payment for the donor. As is outlined in this presentation, we strongly believe that the implementation of these pathways for obtaining organs from the living and the dead donors, with appropriate consideration of the ethical, religious and social criteria of the society, the organ shortage crisis will be eliminated and many lives will be saved through the process of organ donation and

  19. Bifurcation of solutions of nonlinear Sturm–Liouville problems

    Gulgowski Jacek


    Full Text Available A global bifurcation theorem for the following nonlinear Sturm–Liouville problem is given Moreover we give various versions of existence theorems for boundary value problems The main idea of these proofs is studying properties of an unbounded connected subset of the set of all nontrivial solutions of the nonlinear spectral problem , associated with the boundary value problem , in such a way that .

  20. Properties of solutions of optimization problems for set functions

    Slawomir Dorosiewicz


    Full Text Available A definition of a special class of optimization problems with set functions is given. The existence of optimal solutions and first-order optimality conditions are proved. This case of optimal problems can be transformed to standard mixed problems of mathematical programming in Euclidean space. It makes possible the applications of various algorithms for these optimization problems for finding conditional extrema of set functions.

  1. [Utilities: a solution of a decision problem?].

    Koller, Michael; Ohmann, Christian; Lorenz, Wilfried


    Utility is a concept that originates from utilitarianism, a highly influential philosophical school in the Anglo-American world. The cornerstone of utilitarianism is the principle of maximum happiness or utility. In the medical sciences, this utility approach has been adopted and developed within the field of medical decision making. On an operational level, utility is the evaluation of a health state or an outcome on a one-dimensional scale ranging from 0 (death) to 1 (perfect health). By adding the concept of expectancy, the graphic representation of both concepts in a decision tree results in the specification of expected utilities and helps to resolve complex medical decision problems. Criticism of the utility approach relates to the rational perspective on humans (which is rejected by a considerable fraction of research in psychology) and to the artificial methods used in the evaluation of utility, such as Standard Gamble or Time Trade Off. These may well be the reason why the utility approach has never been accepted in Germany. Nevertheless, innovative concepts for defining goals in health care are urgently required, as the current debate in Germany on "Nutzen" (interestingly translated as 'benefit' instead of as 'utility') and integrated outcome models indicates. It remains to be seen whether this discussion will lead to a re-evaluation of the utility approach.

  2. Solution of the Kirchhoff-Plateau Problem

    Giusteri, Giulio G.; Lussardi, Luca; Fried, Eliot


    The Kirchhoff-Plateau problem concerns the equilibrium shapes of a system in which a flexible filament in the form of a closed loop is spanned by a liquid film, with the filament being modeled as a Kirchhoff rod and the action of the spanning surface being solely due to surface tension. We establish the existence of an equilibrium shape that minimizes the total energy of the system under the physical constraint of noninterpenetration of matter, but allowing for points on the surface of the bounding loop to come into contact. In our treatment, the bounding loop retains a finite cross-sectional thickness and a nonvanishing volume, while the liquid film is represented by a set with finite two-dimensional Hausdorff measure. Moreover, the region where the liquid film touches the surface of the bounding loop is not prescribed a priori. Our mathematical results substantiate the physical relevance of the chosen model. Indeed, no matter how strong is the competition between surface tension and the elastic response of the filament, the system is always able to adjust to achieve a configuration that complies with the physical constraints encountered in experiments.

  3. Information- problem solving: A review of problems students encounter and instructional solutions

    Walraven, Amber; Brand-Gruwel, Saskia; Boshuizen, Els


    Walraven, A., Brand-Gruwel, S., & Boshuizen, H.P.A. (2008). Information- problem solving: A review of problems students encounter and instructional solutions. Computers in Human Behavior, 24 (3), 623-648.

  4. A Parameter Property of Classical Solutions of Cauchy Problems

    Min He


    Full Text Available This work is concerned with the abstract Cauchy problems that depend on parameters. The goal is to study continuity in the parameters of the classical solutions of the Cauchy problems. The situation considered in this work is when the operator of the Cauchy problem is not densely defined. By applying integrated semigroup theory and the results on continuity in the parameters of C0-semigroup and integrated semigroup, we obtain the results on the existence and continuity in parameters of the classical solutions of the Cauchy problems. The application of the obtained abstract results in a parabolic partial differential equation is discussed in the last section of the paper.

  5. New Variational Solution for the Space Contact Problem

    CAI Ying; HAN Zhen


    In the recent thirty years, a great of investigations have been made in the Wiener-Hopf equations and variational inequalities as two mutually independent problems. In this paper, we investigate the equivalence of the solution of variational inequality and the inversion of the Toeplitz operator when the projection operators P, Q are linear. The solution of general Wiener-Hopf equation is concluded as the solution of a variational problem. Thus an approximation method of obtaining the maximum value by variational is proposed to obtain the approximation of general Wiener-Hopf equation and apply it to the space contact problems in the elasticity theory. Especially, the solution representation is given in case that the projection of contact surface is round. The closing-form solution is also given when the known displacement is a polynomial of even power.

  6. Cashier Problem: a Greedy Algorithm and an optimal Solution



    Full Text Available We will remind briefly the cashier problem. A cashier has leeway a range of different fractional coins and has to pay a certain amount using the most reduced number of coins. If we mark the pay-desk monetary with P {p ,..., pn } 1 = , each pi having as denomination di and with A the final sum, the cashier must determine a coins subset { } m S q ,..., q 1 = of P, so that i m i id q A Σ==1. In order to solve this problem, there are several solutions consisting in greedy algorithms. Although there is an optimal solution, in the present article we will highlight a greedy algorithm and an optimal solution for this problem. The solution known at the time being use a lot of memory and, in addition, is difficult to justify, occurring the risk of misunderstanding by the reader. Our solution is simpler and uses little memory

  7. Common Problems and Solutions for Being Physically Active

    ... Problems & Solutions for Being Active - FAQs About Physical Activity Managing Your Medicines - Introduction - Taking Control of Your Medicines - Medicine Assistance Programs - Medicine Checklist - Medication Tracker Communicating with Professionals - Introduction - Preparing for Medical Visits - ...

  8. Positive Solutions for Higher Order Singular -Laplacian Boundary Value Problems

    Guoliang Shi; Junhong Zhang


    This paper investigates $2m-\\mathrm{th}(m≥ 2)$ order singular -Laplacian boundary value problems, and obtains the necessary and sufficient conditions for existence of positive solutions for sublinear 2-th order singular -Laplacian BVPs on closed interval.

  9. A solution of Problem 26 of P. Turan



    Explicit formulas for Cotes numbers of the Gaussian Hermite quadrature formula based on the zeros of the nth Chebyshev polynomial and their asymptotic behavior as n→∞ are given. This provides a solution of Problem 26 of P. Turan.

  10. Rose solutions with three petals for planar 4-body problems


    For planar Newtonian 4-body problems with equal masses, we use variational methods to prove the existence of a non-collision periodic choreography solution such that all bodies move on a rose-type curve with three petals.

  11. Problems and Possible Solutions in Reading Comprehension Testing

    Yun Zong


    The paper deals with the problems in reading testing papers. The author proposes some possible solutions, such as covering more cognitive skills being tested, increasing more text types, adding some other testing item types.

  12. Hamilton's Principle and Approximate Solutions to Problems in Classical Mechanics

    Schlitt, D. W.


    Shows how to use the Ritz method for obtaining approximate solutions to problems expressed in variational form directly from the variational equation. Application of this method to classical mechanics is given. (MLH)

  13. The Reasons and Solutions for Problems in Rural School Consolidation

    Qingyang, Guo


    Based on investigations in six midwestern provinces/autonomous regions, Hubei, Henan, Guangxi, Yunnan, Shaanxi, and Inner Mongolia, this article analyzes the reasons for problems in the process of consolidating rural schools and their solutions.

  14. Solutions to problems identified in North African arts and architecture

    Solutions to problems identified in North African arts and architecture. ... Journal of Research in National Development ... viable tourists conservation agency, community- based cultural heritage management, establishment of cultural Ministry ...

  15. A family of Solutions of the N-Body Problem

    Perdomo, Oscar


    In this paper we characterize all the solutions of the three body problem on which one body with mass $m_1$ remains in a fixed line and the other two bodies have the same mass $m_2$. We show that all the solutions with negative total energy (potential plus kinetic), never collide. "Explicit" solutions of the motion of all the three bodies are given in term of just one solution of an ordinary differential equation of order two of one real value function. We show that the solutions of a big sub...

  16. DSP-128:Stream Cipher Based On Discrete Log Problem And Polynomial Arithmetic

    M. K. Suwais


    Full Text Available DSP-128 is a new multithreaded stream cipher based on the intractability of the Discrete Logarithm Problem (DLP with key size of 128-bit. The design of DSP-128 is divided into three stages: Initialization Stage, Keystream Generation Stage, and Encryption Stage. The design goal of DSP-128 is to come up with a secure stream cipher with good performance for data encryption. The experimental results show that the encryption rate of DSP-128 is one time slower (running on single processor than the widely adapted stream cipher RC4, with a higher level of security against possible cryptanalysis attacks. However, because of its multithreaded nature, DSP-128 can take the speed up advantage of multi-core processor architectures which are available widely.

  17. Solution to reinforcement learning problems with artificial potential field

    XIE Li-juan; XIE Guang-rong; CHEN Huan-wen; LI Xiao-li


    A novel method was designed to solve reinforcement learning problems with artificial potential field. Firstly a reinforcement learning problem was transferred to a path planning problem by using artificial potential field(APF), which was a very appropriate method to model a reinforcement learning problem. Secondly, a new APF algorithm was proposed to overcome the local minimum problem in the potential field methods with a virtual water-flow concept. The performance of this new method was tested by a gridworld problem named as key and door maze. The experimental results show that within 45 trials, good and deterministic policies are found in almost all simulations. In comparison with WIERING's HQ-learning system which needs 20 000 trials for stable solution, the proposed new method can obtain optimal and stable policy far more quickly than HQ-learning. Therefore, the new method is simple and effective to give an optimal solution to the reinforcement learning problem.


    A. V. Panteleyev


    Full Text Available This paper presents a hybrid memetic algorithm (MA to solve the problem of finding the optimal program control of nonlinear continuous deterministic systems based on the concept of the meme, which is one of the promising solutions obtained in the course of implementing the procedure for searching the extremes. On the basis of the proposed algorithm the software complex is formed in C#. The solution of satellite transfer problem is presented.

  19. The analytical solution to the problem of statistical induction

    Rodolfo de Cristofaro


    Full Text Available This article is a somewhat personal review of the history and substance of the problem of statistical induction. The main approaches proposed for solving this problem have been examined according to their merits, whit special reference to the analytical solution supported by Carnap. This solution has been re-examined in view of certain results, and is proposed again to the attention of the statisticians.

  20. Noniterative Solution of Some Fermat-Weber Location Problems

    Reuven Chen


    Full Text Available The Fermat-Weber problem of optimally locating a service facility in the Euclidean continuous two-dimensional space is usually solved by the iterative process first suggested by Weiszfeld or by later versions thereof. The methods are usually rather efficient, but exceptional problems are described in the literature in which the iterative solution is exceedingly long. These problems are such that the solution either coincides with one of the demand points or nearly coincides with it. We describe a noniterative direct alternative, based on the insight that the gradient components of the individual demand points can be considered as pooling forces with respect to the solution point. It is demonstrated that symmetrical problems can thus be optimally solved with no iterations, in analogy to finding the equilibrium point in statics. These include a well-known ill-conditioned problem and its variants, which can now be easily solved to optimality using geometrical considerations.

  1. A comprehensive mathematical model for hybrid flexible flowshop lot streaming problem

    Fantahun M. Defersha


    Full Text Available Lot streaming is a technique of splitting production lots into smaller sublots in a multi-stage manufacturing systems so that operations of a given lot can be overlapped. This technique can reduce manufacturing makespan and is an effective tool for time-based manufacturing strategy. Several research articles appeared in literature to solve this problem and most of these studies are limited to pure flowshop environments where there is only a single machine in each stage. On the other hand, because of the applicability of hybrid flowshops in different manufacturing settings, the scheduling of these types of shops is also extensively studied by several authors. However, the issue of lot streaming in hybrid flowshop environment is not well studied. In this paper, we aim to initiate research in bridging the gap between the research efforts in flowshop lot streaming and hybrid flowshop scheduling. We present a comprehensive mathematical model for scheduling flexible hybrid flowshop with lot streaming. Numerical example demonstrated that lot streaming can result in larger makespan reduction in hybrid flowshop where there is a limited research than in pure flowshop where research is abundant.

  2. Generalized Solutions for the joint replenishment problem with correction factor

    E. Porras Musalem (Eric); R. Dekker (Rommert)


    textabstractIn this paper we give a complete analysis of the joint replenishment problem (JRP) under constant demands and continuous time. We present a solution method for the JRP when a correction is made for empty replenishments, and we test the solution procedures with real data. We show that the

  3. Existence of two nontrivial solutions for semilinear elliptic problems

    Abdel R. El Amrouss


    Full Text Available This paper concerns the existence of multiple nontrivial solutions for some nonlinear problems. The first nontrivial solution is found using a minimax method, and the second by computing the Leray-Schauder index and the critical group near 0.

  4. Approximated analytical solution to an Ebola optimal control problem

    Hincapié-Palacio, Doracelly; Ospina, Juan; Torres, Delfim F. M.


    An analytical expression for the optimal control of an Ebola problem is obtained. The analytical solution is found as a first-order approximation to the Pontryagin Maximum Principle via the Euler-Lagrange equation. An implementation of the method is given using the computer algebra system Maple. Our analytical solutions confirm the results recently reported in the literature using numerical methods.

  5. General Solution of the Kenamond HE Problem 3

    Kaul, Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    A general solution for programmed burn calculations of the light times produced by a singlepoint initiation of a single HE region surrounding an inert region has been developed. In contrast to the original solutions proposed in References 1 and 2, the detonator is no longer restricted to a location on a Cartesian axis and can be located at any point inside the HE region. This general solution has been implemented in the ExactPack suite of exact solvers for verification problems.

  6. On solute residence time in the storage zones of small streams - experimental study and scaling law

    Schmid, Bernhard


    Transient storage has a major influence on solute transport in streams, on biogeochemical cycling, water quality and on the functioning of aquatic ecosystems. The first part of the research reported here focuses on surface transient storage (STS) zones between groins along small streams. Such groins are used to protect banks, but also to increase habitat diversity and are, thus, not restricted to large rivers. Repeated tracer dilution experiments on the Mödlingbach, a small stream in Austria some 30 km south of Vienna, have been analyzed to determine the solute residence time between groins and to characterize the exchange processes between dead zones and main stream. Pairs of related breakthrough curves were measured in main stream and storage zones, resp., and used subsequently to estimate the solute residence time in the surface dead zones under study. Following previous work (Weitbrecht et al., 2008; Jackson et al., 2012) these residence times were, in turn, expressed as T = -W-.hD- k ?u hE (1) with W denoting groin length, u main stream flow velocity, hD mean water depth between the groins and hE depth at the interface dead zone - main stream. Coefficient k, finally, is thought to depend on a type of hydraulic radius, RD = W.L/(W+L), with L denoting the distance between the groins, measured in main flow direction. Using both the Mödlingbach STS zone data and the results of the aforementioned study (Weitbrecht et al., 2008) the following regression equation was derived (hS denotes main stream water depth): k = 0.00282? RD + 0.00802 hS (2) The second part of this research focuses on the dependency of solute residence time on flow rate, which is important for an improved understanding of longitudinal solute transport in streams and for the application of mathematical models. The scaling law proposed here is based on a physics-related theory combined with extensive data sets available form a decade of stream tracer experiments on the Mödlingbach stream


    Han Houde; Zhou Zhenya; Zheng Chunxiong


    A coupling method of finite element and infinite large element is proposed for the numerical solution of an eigenvalue problem in unbounded domains in this paper. With some conditions satisfied, the considered problem is proved to have discrete spectra. Several numerical experiments are presented. The results demonstrate the feasibility of the proposed method.




  9. Properties of positive solutions to a nonlinear parabolic problem


    This paper deals with the properties of positive solutions to a quasilinear parabolic equation with the nonlinear absorption and the boundary flux. The necessary and sufficient conditions on the global existence of solutions are described in terms of different parameters appearing in this problem. Moreover, by a result of Chasseign and Vazquez and the comparison principle, we deduce that the blow-up occurs only on the boundary (?)Ω. In addition, for a bounded Lipschitz domainΩ, we establish the blow-up rate estimates for the positive solution to this problem with a= 0.

  10. Fast multigrid solution of the advection problem with closed characteristics

    Yavneh, I. [Israel Inst. of Technology, Haifa (Israel); Venner, C.H. [Univ. of Twente, Enschede (Netherlands); Brandt, A. [Weizmann Inst. of Science, Rehovot (Israel)


    The numerical solution of the advection-diffusion problem in the inviscid limit with closed characteristics is studied as a prelude to an efficient high Reynolds-number flow solver. It is demonstrated by a heuristic analysis and numerical calculations that using upstream discretization with downstream relaxation-ordering and appropriate residual weighting in a simple multigrid V cycle produces an efficient solution process. We also derive upstream finite-difference approximations to the advection operator, whose truncation terms approximate {open_quotes}physical{close_quotes} (Laplacian) viscosity, thus avoiding spurious solutions to the homogeneous problem when the artificial diffusivity dominates the physical viscosity.

  11. Hydrogeomorphology of the hyporheic zone: stream solute and fine particle interactions with a dynamic streambed

    Harvey, J.W.; Drummond, J.D.; Martin, R.L.; McPhillips, L.E.; Packman, A.I.; Jerolmack, D.J.; Stonedahl, S.H.; Aubeneau, A.F.; Sawyer, A.H.; Larsen, L.G.; Tobias, C.R.


    Hyporheic flow in streams has typically been studied separately from geomorphic processes. We investigated interactions between bed mobility and dynamic hyporheic storage of solutes and fine particles in a sand-bed stream before, during, and after a flood. A conservatively transported solute tracer (bromide) and a fine particles tracer (5 μm latex particles), a surrogate for fine particulate organic matter, were co-injected during base flow. The tracers were differentially stored, with fine particles penetrating more shallowly in hyporheic flow and retained more efficiently due to the high rate of particle filtration in bed sediment compared to solute. Tracer injections lasted 3.5 h after which we released a small flood from an upstream dam one hour later. Due to shallower storage in the bed, fine particles were rapidly entrained during the rising limb of the flood hydrograph. Rather than being flushed by the flood, we observed that solutes were stored longer due to expansion of hyporheic flow paths beneath the temporarily enlarged bedforms. Three important timescales determined the fate of solutes and fine particles: (1) flood duration, (2) relaxation time of flood-enlarged bedforms back to base flow dimensions, and (3) resulting adjustments and lag times of hyporheic flow. Recurrent transitions between these timescales explain why we observed a peak accumulation of natural particulate organic matter between 2 and 4 cm deep in the bed, i.e., below the scour layer of mobile bedforms but above the maximum depth of particle filtration in hyporheic flow paths. Thus, physical interactions between bed mobility and hyporheic transport influence how organic matter is stored in the bed and how long it is retained, which affects decomposition rate and metabolism of this southeastern Coastal Plain stream. In summary we found that dynamic interactions between hyporheic flow, bed mobility, and flow variation had strong but differential influences on base flow retention and

  12. Fast, Approximate Solutions for 1D Multicomponent Gas Injection Problems

    Jessen, Kristian; Wang, Yun; Ermakov, Pavel


    by the geometry of key tie lines. It has previously been proven that for systems with an arbitrary number of components, the key tie lines can be approximated quite accurately by a sequence of intersecting tie lines. As a result, analytical solutions can be constructed efficiently for problems with constant...... initial and injection compositions (Riemann problems). For fully self-sharpening systems, in which all key tie lines are connected by shocks, the analytical solutions obtained are rigorously accurate, while for systems in which some key tie lines are connected by spreading waves, the analytical solutions...... finite difference compositional simulation. Therefore, the new approach is, valuable in situations requiring fast compositional solutions to, Riemann problems are required....

  13. Self-similar solutions to isothermal shock problems

    Deschner, Stephan C; Duschl, Wolfgang J


    We investigate exact solutions for isothermal shock problems in different one-dimensional geometries. These solutions are given as analytical expressions if possible, or are computed using standard numerical methods for solving ordinary differential equations. We test the numerical solutions against the analytical expressions to verify the correctness of all numerical algorithms. We use similarity methods to derive a system of ordinary differential equations (ODE) yielding exact solutions for power law density distributions as initial conditions. Further, the system of ODEs accounts for implosion problems (IP) as well as explosion problems (EP) by changing the initial or boundary conditions, respectively. Taking genuinely isothermal approximations into account leads to additional insights of EPs in contrast to earlier models. We neglect a constant initial energy contribution but introduce a parameter to adjust the initial mass distribution of the system. Moreover, we show that due to this parameter a constant...

  14. Unbounded Periodic Solutions to Serrin's Overdetermined Boundary Value Problem

    Fall, Mouhamed Moustapha; Minlend, Ignace Aristide; Weth, Tobias


    We study the existence of nontrivial unbounded domains {Ω} in RN such that the overdetermined problem {-Δ u = 1 quad in Ω}, quad u = 0, quad partial_{ν} u = const quad on partial Ω admits a solution u. By this, we complement Serrin's classification result from 1971, which yields that every bounded domain admitting a solution of the above problem is a ball in RN. The domains we construct are periodic in some variables and radial in the other variables, and they bifurcate from a straight (generalized) cylinder or slab. We also show that these domains are uniquely self Cheeger relative to a period cell for the problem.

  15. Solution of adsorption problems involving steep moving profiles

    Kiil, Søren; Bhatia, Suresh K.


    The moving finite element collocation method proposed by Kiil et al. (1995) for solution of problems with steep gradients is further developed to solve transient problems arising in the field of adsorption. The technique is applied to a model of adsorption in solids with bidisperse pore structures...... methods fail or require a prohibitive number of collocation points. The technique is general in nature and may also be applied to a large variety of multiphase transient heat or mass transfer problems involving steep gradients........ Numerical solutions were found to match the analytical solution when it exists (i.e. when the adsorption isotherm is linear). Results of this application study show that the method is simple yet sufficiently accurate for use in adsorption problems with steep moving gradients, where global collocation...

  16. Fundamental solutions for plane problem of piezoelectric materials

    丁皓江; 王国庆; 陈伟球


    Based on the basic equations of two-dimensional, transversely isotropic, piezoelectric elasticity, a group of general solutions for body force problem is obtained. And by utilizing this group of general solutions and employing the body potential theory and the integral method, the closed-form solutions of displacements and electric potential for an infinite piezoelectric plane loaded by point forces and point charge are acquired. Therefore, the fundamental solutions, which are very important and useful in the boundary element method (BEM), are presented.

  17. Numerical Solution of Turbulence Problems by Solving Burgers’ Equation

    Alicia Cordero


    Full Text Available In this work we generate the numerical solutions of Burgers’ equation by applying the Crank-Nicholson method and different schemes for solving nonlinear systems, instead of using Hopf-Cole transformation to reduce Burgers’ equation into the linear heat equation. The method is analyzed on two test problems in order to check its efficiency on different kinds of initial conditions. Numerical solutions as well as exact solutions for different values of viscosity are calculated, concluding that the numerical results are very close to the exact solution.

  18. Large eddy simulation of turbulence and solute transport in a forested headwater stream

    Khosronejad, A.; Hansen, A. T.; Kozarek, J. L.; Guentzel, K.; Hondzo, M.; Guala, M.; Wilcock, P.; Finlay, J. C.; Sotiropoulos, F.


    The large eddy simulation (LES) module of the Virtual StreamLab (VSL3D) model is applied to simulate the flow and transport of a conservative tracer in a headwater stream in Minnesota, located in the south Twin Cities metropolitan area. The detailed geometry of the stream reach, which is ˜135 m long, ˜2.5 m wide, and ˜0.15 m deep, was surveyed and used as input to the computational model. The detailed geometry and location of large woody debris and bed roughness elements up to ˜0.1 m in size were also surveyed and incorporated in the numerical simulation using the Curvilinear Immersed Boundary approach employed in VSL3D. The resolution of the simulation, which employs up to a total of 25 million grid nodes to discretize the flow domain, is sufficiently fine to directly account for the effect of large woody debris and small cobbles (on the streambed) on the flow patterns and transport processes of conservative solutes. Two tracer injection conditions, a pulse and a plateau release, and two cross sections of measured velocity were used to validate the LES results. The computed results are shown to be in good agreement with the field measurements and tracer concentration time series. To our knowledge, the present study is the first attempt to simulate via high-resolution LES solute transport in a natural stream environment taking into account a range of roughness length scales spanning an order of magnitude: from small cobbles on the streambed (˜0.1 m in diameter) to large woody debris up to ˜3 m long.

  19. Solution procedure of dynamical contact problems with friction

    Abdelhakim, Lotfi


    Dynamical contact is one of the common research topics because of its wide applications in the engineering field. The main goal of this work is to develop a time-stepping algorithm for dynamic contact problems. We propose a finite element approach for elastodynamics contact problems [1]. Sticking, sliding and frictional contact can be taken into account. Lagrange multipliers are used to enforce non-penetration condition. For the time discretization, we propose a scheme equivalent to the explicit Newmark scheme. Each time step requires solving a nonlinear problem similar to a static friction problem. The nonlinearity of the system of equation needs an iterative solution procedure based on Uzawa's algorithm [2][3]. The applicability of the algorithm is illustrated by selected sample numerical solutions to static and dynamic contact problems. Results obtained with the model have been compared and verified with results from an independent numerical method.

  20. DROMO formulation for planar motions: solution to the Tsien problem

    Urrutxua, Hodei; Morante, David; Sanjurjo-Rivo, Manuel; Peláez, Jesús


    The two-body problem subject to a constant radial thrust is analyzed as a planar motion. The description of the problem is performed in terms of three perturbation methods: DROMO and two others due to Deprit. All of them rely on Hansen's ideal frame concept. An explicit, analytic, closed-form solution is obtained for this problem when the initial orbit is circular (Tsien problem), based on the DROMO special perturbation method, and expressed in terms of elliptic integral functions. The analytical solution to the Tsien problem is later used as a reference to test the numerical performance of various orbit propagation methods, including DROMO and Deprit methods, as well as Cowell and Kustaanheimo-Stiefel methods.

  1. Fuzzy α-minimum spanning tree problem: definition and solutions

    Zhou, Jian; Chen, Lu; Wang, Ke; Yang, Fan


    In this paper, the minimum spanning tree problem is investigated on the graph with fuzzy edge weights. The notion of fuzzy ? -minimum spanning tree is presented based on the credibility measure, and then the solutions of the fuzzy ? -minimum spanning tree problem are discussed under different assumptions. First, we respectively, assume that all the edge weights are triangular fuzzy numbers and trapezoidal fuzzy numbers and prove that the fuzzy ? -minimum spanning tree problem can be transformed to a classical problem on a crisp graph in these two cases, which can be solved by classical algorithms such as the Kruskal algorithm and the Prim algorithm in polynomial time. Subsequently, as for the case that the edge weights are general fuzzy numbers, a fuzzy simulation-based genetic algorithm using Prüfer number representation is designed for solving the fuzzy ? -minimum spanning tree problem. Some numerical examples are also provided for illustrating the effectiveness of the proposed solutions.

  2. Problems of Newly-Founded Universities and Solution Offers

    Didem DOĞAN


    Full Text Available Many new universities have recently been founded due to economic, social and cultural reasons in our country. These universities face various problems stemming from whether their locations or their organizational structures. Revealing problems experienced within these newly-founded universities and developing possible solutions for these problems are important in in order to increase the service quality provided by higher education which is one of the most important institutions that generate qualified human power. In this study, the problems of the universities founded after 2006 have been put forth with both administrative and academic staffs' view points and solution offers have been developed towards these problems with a common point of view. In this study in which quantitative and qualitative research methods used, is used Scale of Academicians' Problems was applied to 150 academics as the data gathering device. In order to profoundly examine the data acquired by the scale, two administrative personnel were interviewed and a focus-group interview was performed with eight academics. According to the study data, the most important problem of newly-founded universities is the lack of institutionalization. Physical inadequacy and lack of qualified personnel follow this problem. Efficient management and forming an efficient organization structure are among suggested solution offers.

  3. Polynomial Eigenvalue Solutions to Minimal Problems in Computer Vision.

    Kukelova, Zuzana; Bujnak, Martin; Pajdla, Tomas


    We present a method for solving systems of polynomial equations appearing in computer vision. This method is based on polynomial eigenvalue solvers and is more straightforward and easier to implement than the state-of-the-art Gröbner basis method since eigenvalue problems are well studied, easy to understand, and efficient and robust algorithms for solving these problems are available. We provide a characterization of problems that can be efficiently solved as polynomial eigenvalue problems (PEPs) and present a resultant-based method for transforming a system of polynomial equations to a polynomial eigenvalue problem. We propose techniques that can be used to reduce the size of the computed polynomial eigenvalue problems. To show the applicability of the proposed polynomial eigenvalue method, we present the polynomial eigenvalue solutions to several important minimal relative pose problems.

  4. Analytic Solution to Shell Boundary – Value Problems

    Yu. I. Vinogradov


    Full Text Available Object of research is to find analytical solution to the shell boundary – value problems, i.e. to consider the solution for a class of problems concerning the mechanics of hoop closed shells strain.The objective of work is to create an analytical method to define a stress – strain state of shells under non-axisymmetric loading. Thus, a main goal is to derive the formulas – solutions of the linear ordinary differential equations with variable continuous coefficients.The partial derivative differential equations of mechanics of shells strain by Fourier's method of variables division are reduced to the system of the differential equations with ordinary derivatives. The paper presents the obtained formulas to define solutions of the uniform differential equations and received on their basis formulas to define a particular solution depending on a type of the right parts of the differential equations.The analytical algorithm of the solution of a boundary task uses an approach to transfer the boundary conditions to the randomly chosen point of an interval of changing independent variable through the solution of the canonical matrix ordinary differential equation with the subsequent solution of system of algebraic equations for compatibility of boundary conditions at this point. Efficiency of algorithm is based on the fact that the solution of the ordinary differential equations is defined as the values of Cauchy – Krylova functions, which meet initial arbitrary conditions.The results of researches presented in work are useful to experts in the field of calculus mathematics, dealing with solution of systems of linear ordinary differential equations and creation of effective analytical computing methods to solve shell boundary – value problems.

  5. A Solution to the Lorentzian Quantum Reality Problem

    Kent, Adrian


    The quantum reality problem is that of finding a mathematically precise definition of a sample space of configurations of beables, events, histories, paths, or other mathematical objects, and a corresponding probability distribution, for any given closed quantum system. Given a solution, we can postulate that physical reality is described by one randomly chosen configuration drawn from the sample space. For a physically sensible solution, this postulate should imply quasiclassical physics in ...

  6. Positive solutions and eigenvalues of nonlocal boundary-value problems

    Jifeng Chu


    Full Text Available We study the ordinary differential equation $x''+lambda a(tf(x=0$ with the boundary conditions $x(0=0$ and $x'(1=int_{eta}^{1}x'(sdg(s$. We characterize values of $lambda$ for which boundary-value problem has a positive solution. Also we find appropriate intervals for $lambda$ so that there are two positive solutions.

  7. Nodal Solutions for a Nonlinear Fourth-Order Eigenvalue Problem

    Ru Yun MA; Bevan THOMPSON


    We are concerned with determining the values of λ, for which there exist nodal solutions of the fourth-order boundary value problem y =λa(x)f(y),00 for all u ≠0. We give conditions on the ratio f (s)/s,at infinity and zero, that guarantee the existence of nodal solutions.The proof of our main results is based upon bifurcation techniques.

  8. A deliberative solution to the social choice problem

    Mladenović Ivan


    Full Text Available Is there a sense in which society makes rational decision in a democratic way that is similar to individual rational decision-making? Social choice theory claims that rational social choice is not possible. Or, at least, that if possible, then the social choice must be dictatorial. I shall present a deliberative solution to the social choice problem. This solution is called deliberative, because it is based on the assumptions of deliberative democracy.

  9. Uncertainty of solute flux estimation in ungauged small streams: potential implications for input-output nutrient mass balances at stream reach scale

    A. Butturini


    Full Text Available Input-output mass balances within stream reaches provide in situ estimates of stream nutrient retention/release under a wide spectrum of hydrological conditions. Providing good estimates of the mass balances for nutrients depends on precise hydrological monitoring and good chemical characterisation of stream water at the input and output ends of the stream reach. There is a need to optimise the hydrological monitoring and the frequencies of water sampling to yield precise annual mass balances, so as to avoid undue cost - high resolution monitoring and subsequent chemical analysis can be labour intensive and costly. In this paper, simulation exercises were performed using a data set created to represent the instantaneous discharge and solute dynamics at the input and output ends of a model stream reach during a one year period. At the output end, stream discharge and water chemistry were monitored continuously, while the input end was assumed to be ungauged; water sampling frequency was changed arbitrarily. Instantaneous discharge at the ungauged sampling point was estimated with an empirical power model linking the discharge to the catchment area (Hooper, 1986. The model thus substitutes for the additional gauge station. Simulations showed that 10 days was the longest chemical sampling interval which could provide reach annual mass balances of acceptable precision. Presently, the relationship between discharge and catchment area is usually assumed to be linear but simulations indicate that small departures from the linearity of this relationship could cause dramatic changes in the mass balance estimations.

  10. Collinear Equilibrium Solutions of Four-body Problem

    Muhammad Shoaib; Ibrahima Faye


    We discuss the equilibrium solutions of four different types of collinear four-body problems having two pairs of equal masses. Two of these four-body models are symmetric about the center-of-mass while the other two are non-symmetric.We define two mass ratios as 1 = 1/T and 2 = 2/MT, where 1 and 2 are the two unequal masses and T is the total mass of the system. We discuss the existence of continuous family of equilibrium solutions for all the four types of four-body problems.

  11. A new solution for maximal clique problem based sticker model.

    Darehmiraki, Majid


    In this paper, we use stickers to construct a solution space of DNA for the maximal clique problem (MCP). Simultaneously, we also apply the DNA operation in the sticker-based model to develop a DNA algorithm. The results of the proposed algorithm show that the MCP is resolved with biological operations in the sticker-based model for the solution space of the sticker. Moreover, this work presents clear evidence of the ability of DNA computing to solve the NP-complete problem. The potential of DNA computing for the MCP is promising given the operational time complexity of O(nxk).

  12. Transport processes in space physics and astrophysics problems and solutions

    Dosch, Alexander


     This is the problems and solution manual for the graduate text with the same title and published as Lecture Notes in Physics Vol 877 which provides the necessary mathematical and physics background to understand the transport of gases, charged particle gases, energetic charged particles, turbulence, and radiation in an astrophysical and space physics context. The very detailed and self-contained problems and solutions will be an essential part of the training of any graduate student wishing to enter and pursuing research in this field. .

  13. Methodical Instructions For Solutions of Problems in Nuclear Physics

    Troitskaya, N I


    This is a set of methodical instructions for solutions of problems in Nuclear Physics. It is written on the basis of seminars to the course of lectures on``Nuclear Physics'' delivered at the Physical and Mechanical Faculty of the St. Petersburg State Polytechnic University for the students of the 4th Course in ``Technical Physics'' and ``Medical Physics''. The main aim of these methodical instructions is to develop the experience of students in scientific approaches to solutions of practical problems in Nuclear Physics.

  14. Memristor-based memory: The sneak paths problem and solutions

    Zidan, Mohammed A.


    In this paper, we investigate the read operation of memristor-based memories. We analyze the sneak paths problem and provide a noise margin metric to compare the various solutions proposed in the literature. We also analyze the power consumption associated with these solutions. Moreover, we study the effect of the aspect ratio of the memory array on the sneak paths. Finally, we introduce a new technique for solving the sneak paths problem by gating the memory cell using a three-terminal memistor device.

  15. Solution of the determinantal assignment problem using the Grassmann matrices

    Karcanias, Nicos; Leventides, John


    The paper provides a direct solution to the determinantal assignment problem (DAP) which unifies all frequency assignment problems of the linear control theory. The current approach is based on the solvability of the exterior equation ? where ? is an n -dimensional vector space over ? which is an integral part of the solution of DAP. New criteria for existence of solution and their computation based on the properties of structured matrices are referred to as Grassmann matrices. The solvability of this exterior equation is referred to as decomposability of ?, and it is in turn characterised by the set of quadratic Plücker relations (QPRs) describing the Grassmann variety of the corresponding projective space. Alternative new tests for decomposability of the multi-vector ? are given in terms of the rank properties of the Grassmann matrix, ? of the vector ?, which is constructed by the coordinates of ?. It is shown that the exterior equation is solvable (? is decomposable), if and only if ? where ?; the solution space for a decomposable ?, is the space ?. This provides an alternative linear algebra characterisation of the decomposability problem and of the Grassmann variety to that defined by the QPRs. Further properties of the Grassmann matrices are explored by defining the Hodge-Grassmann matrix as the dual of the Grassmann matrix. The connections of the Hodge-Grassmann matrix to the solution of exterior equations are examined, and an alternative new characterisation of decomposability is given in terms of the dimension of its image space. The framework based on the Grassmann matrices provides the means for the development of a new computational method for the solutions of the exact DAP (when such solutions exist), as well as computing approximate solutions, when exact solutions do not exist.

  16. Solution of Contact Problems for Nonlinear Gao Beam and Obstacle

    J. Machalová


    Full Text Available Contact problem for a large deformed beam with an elastic obstacle is formulated, analyzed, and numerically solved. The beam model is governed by a nonlinear fourth-order differential equation developed by Gao, while the obstacle is considered as the elastic foundation of Winkler’s type in some distance under the beam. The problem is static without a friction and modeled either using Signorini conditions or by means of normal compliance contact conditions. The problems are then reformulated as optimal control problems which is useful both for theoretical aspects and for solution methods. Discretization is based on using the mixed finite element method with independent discretization and interpolations for foundation and beam elements. Numerical examples demonstrate usefulness of the presented solution method. Results for the nonlinear Gao beam are compared with results for the classical Euler-Bernoulli beam model.

  17. New solutions in the direct problem of dynamics

    Blaga, C.; Anisiu, M.-C.; Bozis, G.


    Given a planar potential V, we look for families of orbits f(x,y)=c% (determined by their slope function γ=f_{y}/f_{x}), traced by a material point of unit mass under the action of that potential. The second-order equation which relates γ and V is nonlinear in γ; to find special solutions, we consider in addition a linear first-order partial differential equation satisfied by γ. The problem does not admit always solutions; but when solutions do exist, they can be found by algebraic manipulations. Examples are given for homogeneous families γ, and for some special cases which arise in the course of reasoning.

  18. Oscillatory solutions of the Cauchy problem for linear differential equations

    Gro Hovhannisyan


    Full Text Available We consider the Cauchy problem for second and third order linear differential equations with constant complex coefficients. We describe necessary and sufficient conditions on the data for the existence of oscillatory solutions. It is known that in the case of real coefficients the oscillatory behavior of solutions does not depend on initial values, but we show that this is no longer true in the complex case: hence in practice it is possible to control oscillatory behavior by varying the initial conditions. Our Proofs are based on asymptotic analysis of the zeros of solutions, represented as linear combinations of exponential functions.

  19. A generalized eigenvalue problem solution for an uncoupled multicomponent system

    Diago-Cisneros, L; Fernandez-Anaya, G; Bonfanti-Escalera, G [Departamento de Fisica y Matematicas, Universidad Iberoamericana, CP 01219, DF Mexico (Mexico)], E-mail:


    Meaningful and well-founded physical quantities are convincingly determined by eigenvalue problem solutions emerging from a second-order N-coupled system of differential equations, known as the Sturm-Liouville matrix boundary problem. Via the generalized Schur decomposition procedure and imposing to the multicomponent system to be decoupled, which is a widely accepted remarkable physical situation, we have unambiguously demonstrated a simultaneously triangularizable scenario for (2Nx2N) matrices content in a generalized eigenvalue equation.

  20. Continuous Rearrangement and Symmetry of Solutions of Elliptic Problems

    Friedemann Brock


    This work presents new results and applications for the continuous Steiner symmetrization. There are proved some functional inequalities, e.g. for Dirichlet-type integrals and convolutions and also continuity properties in Sobolev spaces 1, . Further it is shown that the local minimizers of some variational problems and the nonnegative solutions of some semilinear elliptic problems in symmetric domains satisfy a weak, `local' kind of symmetry.

  1. Solution for the problem of the game heads or tails

    Costa, Alberto


    In this paper, we describe the solution for a problem dealing with definite properties of binary sequences. This problem, proposed by Xavier Grandsart in the form of a mathematical contest, has been solved also by Maher Younan, Ph.D. student of Theoretical Physics at the University of Geneva, and Pierre Deligne, professor at Princeton and Field Medals, using different approaches with respect to the one presented in this work.


    Yingchun Jiang


    In this paper, we use divergence-free wavelets to give an adaptive solution to the velocity field of the Stokes problem. We first use divergence-free wavelets to discretize the divergence-free weak formulation of the Stokes problem and obtain a discrete positive definite linear system of equations whose coefficient matrix is quasi-sparse; Secondly, an adaptive scheme is used to solve the discrete linear system of equations and the error estimation and complexity analysis are given.

  3. Dirac reduced radial equations and the Problem of Additional Solutions

    Khelashvili, Anzor


    For spinless particles there appear additional solutions in the framework of Schrodinger and Klein-Gordon equations. These solutions obey to all requirements of quantum mechanical general principles. Observation of such states should be important for manifestation of various physical phenomena. In this article the same problem is considered for spin-1/2 particle in the Dirac equation. It is shown that such kind of solutions really occurs, but the rate of singularity is more higher than in spinless case. By this reason we have no time- independence of total probability (norm). Moreover the orthogonality property is also failed, while the total probability is finite in the certain area of the model-parameters. Therefore, we are inclined to conclude that this additional solution in the Dirac equation must be ignored and restrict ourselves only by normal (standard) solutions. Because the question is to determine the asymptotic behaviour of wave function at the origin, using the radial equations, is natural. The s...

  4. Iterative Solutions to the Inverse Geometric Problem for Manipulators with no Closed Form Solution

    Pål Johan From


    Full Text Available A set of new iterative solutions to the inverse geometric problem is presented. The approach is general and does not depend on intersecting axes or calculation of the Jacobian. The solution can be applied to any manipulator and is well suited for manipulators for which convergence is poor for conventional Jacobian-based iterative algorithms. For kinematically redundant manipulators, weights can be applied to each joint to introduce stiffness and for collision avoidance. The algorithm uses the unit quaternion to represent the position of each joint and calculates analytically the optimal position of the joint when only the respective joint is considered. This sub-problem is computationally very efficient due to the analytical solution. Several algorithms based on the solution of this sub-problem are presented. For difficult problems, for which the initial condition is far from a solution or the geometry of the manipulator makes the solution hard to reach, it is shown that the algorithm finds a solution fairly close to the solution in only a few iterations.

  5. Problem solution as a guided activity with Mexican schoolchildren

    Solovieva, Yulia


    Full Text Available The goal of the present study was to describe the organization of a guided activity for problem solution in primary school. The method, which was applied to mathematical problems, allowed us to propose a specific orientation for the proper solution of arithmetic problems by pupils. The study was based on the activity-theory approach applied to the process of teaching and learning. It was carried out with pupils in the second grade of a private school in the city of Puebla (Mexico. The method was used in the classroom during 30 school sessions of 1 hour per day. The methodology of formative experiment was used in the study. Qualitative analysis of the pedagogical process of teaching and learning was conducted. The results show that, after participation in the formative process, the schoolchildren became able to identify essential elements, data, and all relationships among them in order to solve mathematical problems. At the end of the program the verbal external level was raised for the process of orientation and the solution of problems together with the ability to use logarithms independently. We conclude that orientation, as a guided form of activity in primary school, is essential for the development of the ability to analyze problems.

  6. A Stream Morphology Classification for Eco-hydraulic Purposes Based on Geospatial Data: a Solute Transport Application Case

    Jiménez Jaramillo, M. A.; Camacho Botero, L. A.; Vélez Upegui, J. I.


    Variation in stream morphology along a basin drainage network leads to different hydraulic patterns and sediment transport processes. Moreover, solute transport processes along streams, and stream habitats for fisheries and microorganisms, rely on stream corridor structure, including elements such as bed forms, channel patterns, riparian vegetation, and the floodplain. In this work solute transport processes simulation and stream habitat identification are carried out at the basin scale. A reach-scale morphological classification system based on channel slope and specific stream power was implemented by using digital elevation models and hydraulic geometry relationships. Although the morphological framework allows identification of cascade, step-pool, plane bed and pool-riffle morphologies along the drainage network, it still does not account for floodplain configuration and bed-forms identification of those channel types. Hence, as a first application case in order to obtain parsimonious three-dimensional characterizations of drainage channels, the morphological framework has been updated by including topographical floodplain delimitation through a Multi-resolution Valley Bottom Flatness Index assessing, and a stochastic bed form representation of the step-pool morphology. Model outcomes were tested in relation to in-stream water storage for different flow conditions and representative travel times according to the Aggregated Dead Zone -ADZ- model conceptualization of solute transport processes.




    This paper considers the quasi-stationary Stefan problem:△u(x,t)=0 in space-time domain,u=0 and Vv+δu/δv=0 on the free boundary. under the natural conditions the existence of classical solution locally in time is proved by making use of the property of Frechet derivative operator and fixed point theorem. For the sake of simplicity only the one-phase problem is dealt with. In fact two-phase problem can be dealt with in a similar way with more complicated calculation.

  8. Numerical solution of fuzzy boundary value problems using Galerkin method



    This paper proposes a new technique based on Galerkin method for solving nth order fuzzy boundary value problem. The proposed method has been illustrated by considering three different cases depending upon the sign of coefficients with benchmark example problems. To show the applicability of the proposed method, an application problem related to heat conduction has also been studied. The results obtained by the proposed methods are compared with the exact solution and other existing methods for demonstrating the validity and efficiency of the present method.

  9. The p-median Facility Location Problem and Solution Approaches

    Mehmet BASTI


    Full Text Available In today’s globalized and increasingly competitive environment, organizations’ need to implement successful strategies for supply chain management has become indispensable. Transportation costs within the supply chain comprise an important part of the organizations’ expenses. For this reason, the strategic selection of location is an issue that directly affects supply chain performance and costs. At this stage, it becomes very important to apply the latest and the best methods to the facility location problem. The focus of this study is the p-median problem and its solution techniques, one of the location allocation problems aimed at minimizing the costs arising from shipments between facilities and demand points.

  10. Branching solutions to one-dimensional variational problems

    Ivanov, A O


    This book deals with the new class of one-dimensional variational problems - the problems with branching solutions. Instead of extreme curves (mappings of a segment to a manifold) we investigate extreme networks, which are mappings of graphs (one-dimensional cell complexes) to a manifold. Various applications of the approach are presented, such as several generalizations of the famous Steiner problem of finding the shortest network spanning given points of the plane. Contents: Preliminary Results; Networks Extremality Criteria; Linear Networks in R N; Extremals of Length Type Functionals: The

  11. Surveying problem solution with theory and objective type questions

    Chandra, AM


    The book provides a lucid and step-by-step treatment of the various principles and methods for solving problems in land surveying. Each chapter starts with basic concepts and definitions, then solution of typical field problems and ends with objective type questions. The book explains errors in survey measurements and their propagation. Survey measurements are detailed next. These include horizontal and vertical distance, slope, elevation, angle, and direction. Measurement using stadia tacheometry and EDM are then highlighted, followed by various types of levelling problems. Traversing is then explained, followed by a detailed discussion on adjustment of survey observations and then triangulation and trilateration.

  12. Analytical solutions for the surface response to small amplitude perturbations in boundary data in the shallow-ice-stream approximation

    G. H. Gudmundsson


    Full Text Available New analytical solutions describing the effects of small-amplitude perturbations in boundary data on flow in the shallow-ice-stream approximation are presented. These solutions are valid for a non-linear Weertman-type sliding law and for Newtonian ice rheology. Comparison is made with corresponding solutions of the shallow-ice-sheet approximation, and with solutions of the full Stokes equations. The shallow-ice-stream approximation is commonly used to describe large-scale ice stream flow over a weak bed, while the shallow-ice-sheet approximation forms the basis of most current large-scale ice sheet models. It is found that the shallow-ice-stream approximation overestimates the effects of bed topography perturbations on surface profile for wavelengths less than about 5 to 10 ice thicknesses, the exact number depending on values of surface slope and slip ratio. For high slip ratios, the shallow-ice-stream approximation gives a very simple description of the relationship between bed and surface topography, with the corresponding transfer amplitudes being close to unity for any given wavelength. The shallow-ice-stream estimates for the timescales that govern the transient response of ice streams to external perturbations are considerably more accurate than those based on the shallow-ice-sheet approximation. In particular, in contrast to the shallow-ice-sheet approximation, the shallow-ice-stream approximation correctly reproduces the short-wavelength limit of the kinematic phase speed given by solving a linearised version of the full Stokes system. In accordance with the full Stokes solutions, the shallow-ice-sheet approximation predicts surface fields to react weakly to spatial variations in basal slipperiness with wavelengths less than about 10 to 20 ice thicknesses.

  13. Solution of hydraulic fracture problem accounting for lag

    Linkov, Alexander M


    The paper presents a method for solving hydraulic fracture problems accounting for the lag. The method consists in matching the outer (basic) solution neglecting the lag, with the inner (auxiliary) solution of the derived 1D integral equation with conditions, accounting for the lag and asymptotic behavior of the opening and the net-pressure. The method refers to practically important cases, when the influence of the local perturbation, caused by the lag, becomes insignificant at a distance, where the leading plane-state asymptotics near the fracture front is still applicable. The universal asymptotics are used for finding the matching constants of the basic (outer) solution and for formulation of matching condition for the solution of inner (auxiliary) problem. The method is illustrated by the solution of the Spence and Sharp plane-strain problem for a fracture propagating symmetrically from the inlet, where a Newtonian fluid is pumped at a constant rate. It is stated that the method developed for deep fractu...

  14. Radioactive Waste...The Problem and Some Possible Solutions

    Olivier, Jean-Pierre


    Nuclear safety is a highly technical and controversial subject that has caused much heated debate and political concern. This article examines the problems involved in managing radioactive wastes and the techniques now used. Potential solutions are suggested and the need for international cooperation is stressed. (Author/MA)

  15. Approximate solutions of common fixed-point problems

    Zaslavski, Alexander J


    This book presents results on the convergence behavior of algorithms which are known as vital tools for solving convex feasibility problems and common fixed point problems. The main goal for us in dealing with a known computational error is to find what approximate solution can be obtained and how many iterates one needs to find it. According to know results, these algorithms should converge to a solution. In this exposition, these algorithms are studied, taking into account computational errors which remain consistent in practice. In this case the convergence to a solution does not take place. We show that our algorithms generate a good approximate solution if computational errors are bounded from above by a small positive constant. Beginning with an introduction, this monograph moves on to study: · dynamic string-averaging methods for common fixed point problems in a Hilbert space · dynamic string methods for common fixed point problems in a metric space · dynamic string-averaging version of the proximal...

  16. A Solution of Problem 33 of P. Turan’s



    This paper gives a solution of Problem 33 of P. Turan’s as follows. For every integer n>2there is a set of nodes -1 for whichholds for all polynomials of degree <2n, where rk, pk are the fundamental polynomialsof the first kind and the second kind for (0, 2)-interpolation, respeaively.

  17. Symmetric Periodic Solutions of the Anisotropic Manev Problem

    Santoprete, Manuele


    We consider the Manev Potential in an anisotropic space, i.e., such that the force acts differently in each direction. Using a generalization of the Poincare' continuation method we study the existence of periodic solutions for weak anisotropy. In particular we find that the symmetric periodic orbits of the Manev system are perturbed to periodic orbits in the anisotropic problem.

  18. Problems and solutions in thermoelasticity and magneto-thermoelasticity

    Das, B


    This book presents problems and solutions of the mathematical theories of thermoelasticity and magnetothermoelasticity. The classical, coupled and generalized theories are solved using the eigenvalue methodology. Different methods of numerical inversion of the Laplace transform are presented and their direct applications are illustrated. The book is very useful to those interested in continuum mechanics.

  19. Linear iterative technique for solution of nonlinear thermal network problems

    Seabourn, C.M.


    A method for rapid and accurate solution of linear and/or nonlinear thermal network problems is described. It is a matrix iterative process that converges for nodal temperatures and variations of thermal conductivity with temperature. The method is computer oriented and can be changed easily for design studies.



    Under some weaker conditions,we prove the existence of at least two solutions to an asymptotically linear elliptic problem with Robin boundary value condition,using truncation arguments.Our results are also valid for the case of the so-called resonance at infinity.

  1. Multiple solutions for inhomogeneous nonlinear elliptic problems arising in astrophyiscs

    Marco Calahorrano


    Full Text Available Using variational methods we prove the existence and multiplicity of solutions for some nonlinear inhomogeneous elliptic problems on a bounded domain in $mathbb{R}^n$, with $ngeq 2$ and a smooth boundary, and when the domain is $mathbb{R}_+^n$

  2. Properties and solution methods for large location-allocation problems

    Juel, Henrik; Love, Robert F.


    Location-allocation with l$ _p$ distances is studied. It is shown that this structure can be expressed as a concave minimization programming problem. Since concave minimization algorithms are not yet well developed, five solution methods are developed which utilize the special properties of the l...

  3. Homographic solutions of the curved 3-body problem

    Diacu, Florin


    In the 2-dimensional curved 3-body problem, we prove the existence of Lagrangian and Eulerian homographic orbits, and provide their complete classification in the case of equal masses. We also show that the only non-homothetic hyperbolic Eulerian solutions are the hyperbolic Eulerian relative equilibria, a result that proves their instability.

  4. Image Indexing and Retrieval: Some Problems and Proposed Solutions.

    Baxter, Graeme; Anderson, Douglas


    Image processing technology allows libraries to include photographs, paintings, monograph title pages, and maps in their databases. This article examines problems of and solutions to image indexing and retrieval, focusing on thesaurus-based indexing systems, visual thesauri and related hybrid systems, picture description languages, and image…

  5. Some methods for solution of quantum detection and measurement problems

    Grishanin, Boris A.


    Representation of the quantum measurement with the help of non-orthogonal decomposition of unit is presented in the paper for the first time. Methods for solution of the quantum detection and measurement problems based on the suggested representation are proposed, as well.



    In this paper, we study a class of fourth-order Neumann boundary value problem (NBVP for short). By virtue of fixed point index and the spectral theory of linear operators, the existence of positive solutions is obtained under the assumption that the nonlinearity satisfies sublinear or superlinear conditions, which are relevant to the first eigenvalue of the corresponding linear operator.

  7. Two-Dimensional Rectangular Stock Cutting Problem and Solution Methods

    Zhao Hui; Yu Liang; Ning Tao; Xi Ping


    Optimal layout of rectangular stock cutting is still in great demand from industry for diversified applications. This paper introduces four basic solution methods to the problem: linear programming, dynamic programming, tree search and heuristic approach. A prototype of application software is developed to verify the pros and cons of various approaches.

  8. Water--Problems and Solutions. A Report Concerning the Problems and Solutions of Negative Water Balance.

    Ewert, Alan

    Outdoor leaders constantly face problems created by water shortage and, to act effectively, must thoroughly understand the body's use of water and the ways to delay dehydration when water shortage occurs. Dehydration begins when there is a negative water balance, or more water lost than ingested, and progresses from the stage of dryness, to the…

  9. Biological regeneration of ferric ("Fe3+") solution during desulphurisation of gaseous streams: effect of nutrients and support material

    Mulopo, J


    Full Text Available This paper evaluates the biological regeneration of ferric Fe3+ solution during desulphurisation of gaseous streams. Hydrogen sulphide (H2S) is absorbed into aqueous ferric sulphate solution and oxidised to elemental sulphur, while ferric ions Fe3...


    Jianliang TANG; Wensheng CHEN


    In the PnP problem, the imaging devices follow the perspective rule and the imaging rays pass through a common point. However, there are many new imaging devices being developed for robot navigation or other fields with the advance in imaging technologies for machine vision. These devise are not necessarily being designed to follow the perspective rule in order to satisfy some design criterion and, thus, the imaging rays may not pass through a common point. Such generalized imaging devices may not be perspective and, therefore, their poses cannot be estimated with traditional perspective technique. Using the Wu-Ritt's zero decomposition method, the main component for the nonperspective-threepoint problem is given. We prove that there are at most eight solutions in the general case and give the solution classification for the NP3P problem.

  11. Water implications in Mediterranean irrigation networks: Problems and solutions

    Laura Romero Marrero, Modesto Pérez-Sánchez, P. Amparo López-Jiménez


    Full Text Available Agriculture is a significant user of water and energy in Mediterranean coasts of Europe, such as Spanish Mediterranean regions. Water implications of such irrigations are well known but there are many problems that must be taken into account when designing each phase of the irrigation system, not only in the construction phase but in the exploitation, control and maintenance of all the elements in the network. All the possible problems in each part of the irrigation system will be analyzed in the following paper, proposing several solutions to avoid these problems or mitigate its consequences. These solutions go from the simple maintenance of pipes and valeus to the implementation of more sophisticated systems, such as SCADA, or management strategies, such as benchmarking.

  12. A solution of LIDAR problem in double scattering approximation

    Leble, Sergey


    A problem of monoenergetic particles pulse reflection from half-infinite stratified medium is considered in conditions of elastic scattering with absorbtion account. The theory is based on multiple scattering series solution of Kolmogorov equation for one-particle distribution function. The analytical representation for first two terms are given in compact form for a point impulse source and cylindric symmetrical detector. Reading recent articles on the LIDAR sounding of environment (e.g. Atmospheric and Oceanic Optics (2010) 23: 389-395, Kaul, B. V.; Samokhvalov, I. V. one recovers standing interest to the related direct and inverse problems. A development of the result fo the case of n-fold scattering and polarization account as well as correspondent convergence series problem solution of the Kolmogorov equation will be published in nearest future.

  13. Vectorial solutions to list multicoloring problems on graphs

    Aubry, Yves; Togni, Olivier


    For a graph $G$ with a given list assignment $L$ on the vertices, we give an algebraical description of the set of all weights $w$ such that $G$ is $(L,w)$-colorable, called permissible weights. Moreover, for a graph $G$ with a given list $L$ and a given permissible weight $w$, we describe the set of all $(L,w)$-colorings of $G$. By the way, we solve the {\\sl channel assignment problem}. Furthermore, we describe the set of solutions to the {\\sl on call problem}: when $w$ is not a permissible weight, we find all the nearest permissible weights $w'$. Finally, we give a solution to the non-recoloring problem keeping a given subcoloring.

  14. Water age and stream solute dynamics at the Hubbard Brook Experimental Forest (US)

    Botter, Gianluca; Benettin, Paolo; McGuire, Kevin; Rinaldo, Andrea


    The contribution discusses experimental and modeling results from a headwater catchment at the Hubbard Brook Experimental Forest (New Hampshire, USA) to explore the link between stream solute dynamics and water age. A theoretical framework based on water age dynamics, which represents a general basis for characterizing solute transport at the catchment scale, is used to model both conservative and weathering-derived solutes. Based on the available information about the hydrology of the site, an integrated transport model was developed and used to estimate the relevant hydrochemical fluxes. The model was designed to reproduce the deuterium content of streamflow and allowed for the estimate of catchment water storage and dynamic travel time distributions (TTDs). Within this framework, dissolved silicon and sodium concentration in streamflow were simulated by implementing first-order chemical kinetics based explicitly on dynamic TTD, thus upscaling local geochemical processes to catchment scale. Our results highlight the key role of water stored within the subsoil glacial material in both the short-term and long-term solute circulation at Hubbard Brook. The analysis of the results provided by the calibrated model allowed a robust estimate of the emerging concentration-discharge relationship, streamflow age distributions (including the fraction of event water) and storage size, and their evolution in time due to hydrologic variability.

  15. Reactive Solute Transport in Streams: 1. Development of an Equilibrium-Based Model

    Runkel, Robert L.; Bencala, Kenneth E.; Broshears, Robert E.; Chapra, Steven C.


    An equilibrium-based solute transport model is developed for the simulation of trace metal fate and transport in streams. The model is formed by coupling a solute transport model with a chemical equilibrium submodel based on MINTEQ. The solute transport model considers the physical processes of advection, dispersion, lateral inflow, and transient storage, while the equilibrium submodel considers the speciation and complexation of aqueous species, precipitation/dissolution and sorption. Within the model, reactions in the water column may result in the formation of solid phases (precipitates and sorbed species) that are subject to downstream transport and settling processes. Solid phases on the streambed may also interact with the water column through dissolution and sorption/desorption reactions. Consideration of both mobile (water-borne) and immobile (streambed) solid phases requires a unique set of governing differential equations and solution techniques that are developed herein. The partial differential equations describing physical transport and the algebraic equations describing chemical equilibria are coupled using the sequential iteration approach.

  16. Reactive solute transport in streams. 1. Development of an equilibrium- based model

    Runkel, R.L.; Bencala, K.E.; Broshears, R.E.; Chapra, S.C.


    An equilibrium-based solute transport model is developed for the simulation of trace metal fate and transport in streams. The model is formed by coupling a solute transport model with a chemical equilibrium submodel based on MINTEQ. The solute transport model considers the physical processes of advection, dispersion, lateral inflow, and transient storage, while the equilibrium submodel considers the speciation and complexation of aqueous species, precipitation/dissolution and sorption. Within the model, reactions in the water column may result in the formation of solid phases (precipitates and sorbed species) that are subject to downstream transport and settling processes. Solid phases on the streambed may also interact with the water column through dissolution and sorption/desorption reactions. Consideration of both mobile (water-borne) and immobile (streambed) solid phases requires a unique set of governing differential equations and solution techniques that are developed herein. The partial differential equations describing physical transport and the algebraic equations describing chemical equilibria are coupled using the sequential iteration approach.

  17. Green's function solution to spherical gradiometric boundary-value problems

    Martinec, Z.


    Three independent gradiometric boundary-value problems (BVPs) with three types of gradiometric data, {orr}, {or/,or5} and {o//mo55,o/5}, prescribed on a sphere are solved to determine the gravitational potential on and outside the sphere. The existence and uniqueness conditions on the solutions are formulated showing that the zero- and the first-degree spherical harmonics are to be removed from {or/,or5} and {o//mo55,o/5}, respectively. The solutions to the gradiometric BVPs are presented in terms of Green's functions, which are expressed in both spectral and closed spatial forms. The logarithmic singularity of the Green's function at the point `=0 is investigated for the component orr. The other two Green's functions are finite at this point. Comparisons to the paper by van Gelderen and Rummel [Journal of Geodesy (2001) 75: 1-11] show that the presented solution refines the former solution.

  18. Haydock's recursive solution of self-adjoint problems. Discrete spectrum

    Moroz, Alexander


    Haydock's recursive solution is shown to underline a number of different concepts such as (i) quasi-exactly solvable models, (ii) exactly solvable models, (iii) three-term recurrence solutions based on Schweber's quantization criterion in Hilbert spaces of entire analytic functions, and (iv) a discrete quantum mechanics of Odake and Sasaki. A recurrent theme of Haydock's recursive solution is that the spectral properties of any self-adjoint problem can be mapped onto a corresponding sequence of polynomials {pn(E) } in energy variable E. The polynomials {pn(E) } are orthonormal with respect to the density of states n0(E) and energy eigenstate | E > is the generating function of {pn(E) } . The generality of Haydock's recursive solution enables one to see the different concepts from a unified perspective and mutually benefiting from each other. Some results obtained within the particular framework of any of (i) to (iv) may have much broader significance.

  19. Numerical solution-space analysis of satisfiability problems

    Mann, Alexander; Hartmann, A. K.


    The solution-space structure of the three-satisfiability problem (3-SAT) is studied as a function of the control parameter α (ratio of the number of clauses to the number of variables) using numerical simulations. For this purpose one has to sample the solution space with uniform weight. It is shown here that standard stochastic local-search (SLS) algorithms like average satisfiability (ASAT) exhibit a sampling bias, as does “Metropolis-coupled Markov chain Monte Carlo” (MCMCMC) (also known as “parallel tempering”) when run for feasible times. Nevertheless, unbiased samples of solutions can be obtained using the “ballistic-networking approach,” which is introduced here. It is a generalization of “ballistic search” methods and yields also a cluster structure of the solution space. As application, solutions of 3-SAT instances are generated using ASAT plus ballistic networking. The numerical results are compatible with a previous analytical prediction of a simple solution-space structure for small values of α and a transition to a clustered phase at αc≈3.86 , where the solution space breaks up into several non-negligible clusters. Furthermore, in the thermodynamic limit there are, even for α=4.25 close to the SAT-UNSAT transition αs≈4.267 , always clusters without any frozen variables. This may explain why some SLS algorithms are able to solve very large 3-SAT instances close to the SAT-UNSAT transition.

  20. WYD method for an eigen solution of coupled problems

    A Harapin


    Full Text Available Designing efficient and stable algorithm for finding the eigenvalues andeigenvectors is very important from the static as well as the dynamic aspectin coupled problems. Modal analysis requires first few significant eigenvectorsand eigenvalues while direct integration requires the highest value toascertain the length of the time step that satisfies the stability condition.The paper first presents the modification of the well known WYDmethod for a solution of single field problems: an efficient and numericallystable algorithm for computing eigenvalues and the correspondingeigenvectors. The modification is based on the special choice of thestarting vector. The starting vector is the static solution of displacements forthe applied load, defined as the product of the mass matrix and the unitdisplacement vector. The starting vector is very close to the theoreticalsolution, which is important in cases of small subspaces.Additionally, the paper briefly presents the adopted formulation for solvingthe fluid-structure coupled systems problems which is based on a separatesolution for each field. Individual fields (fluid and structure are solvedindependently, taking in consideration the interaction information transferbetween them at every stage of the iterative solution process. The assessmentof eigenvalues and eigenvectors for multiple fields is also presented. This eigenproblem is more complicated than the one for the ordinary structural analysis,as the formulation produces non-symmetrical matrices.Finally, a numerical example for the eigen solution coupled fluidstructureproblem is presented to show the efficiency and the accuracy ofthe developed algorithm.

  1. Web 2.0 Solutions to Wicked Climate Change Problems

    Alanah Kazlauskas


    Full Text Available One of the most pressing ‘wicked problems’ facing humankind is climate change together with its many interrelated environmental concerns. The complexity of this set of problems can be overwhelming as there is such diversity among both the interpretations of the scientific evidence and the viability of possible solutions. Among the social technologies associated with the second generation of the Internet known as Web 2.0, there are tools that allow people to communicate, coordinate and collaborate in ways that reduce their carbon footprint and a potential to become part of the climate change solution. However the way forward is not obvious or easy as Web 2.0, while readily accepted in the chaotic social world, is often treated with suspicion in the more ordered world of business and government. This paper applies a holistic theoretical sense-making framework to research and practice on potential Web 2.0 solutions to climate change problems. The suite of issues, activities and tools involved are viewed as an ecosystem where all elements are dynamic and inter-related. Through such innovative thinking the Information Systems community can make a valuable contribution to a critical global problem and hence find a new relevance as part of the solution.

  2. Lessons Learned During Solutions of Multidisciplinary Design Optimization Problems

    Patnaik, Suna N.; Coroneos, Rula M.; Hopkins, Dale A.; Lavelle, Thomas M.


    Optimization research at NASA Glenn Research Center has addressed the design of structures, aircraft and airbreathing propulsion engines. During solution of the multidisciplinary problems several issues were encountered. This paper lists four issues and discusses the strategies adapted for their resolution: (1) The optimization process can lead to an inefficient local solution. This deficiency was encountered during design of an engine component. The limitation was overcome through an augmentation of animation into optimization. (2) Optimum solutions obtained were infeasible for aircraft and air-breathing propulsion engine problems. Alleviation of this deficiency required a cascading of multiple algorithms. (3) Profile optimization of a beam produced an irregular shape. Engineering intuition restored the regular shape for the beam. (4) The solution obtained for a cylindrical shell by a subproblem strategy converged to a design that can be difficult to manufacture. Resolution of this issue remains a challenge. The issues and resolutions are illustrated through six problems: (1) design of an engine component, (2) synthesis of a subsonic aircraft, (3) operation optimization of a supersonic engine, (4) design of a wave-rotor-topping device, (5) profile optimization of a cantilever beam, and (6) design of a cvlindrical shell. The combined effort of designers and researchers can bring the optimization method from academia to industry.

  3. Is comprehension of problem solutions resistant to misleading heuristic cues?

    Ackerman, Rakefet; Leiser, David; Shpigelman, Maya


    Previous studies in the domain of metacomprehension judgments have primarily used expository texts. When these texts include illustrations, even uninformative ones, people were found to judge that they understand their content better. The present study aimed to delineate the metacognitive processes involved in understanding problem solutions - a text type often perceived as allowing reliable judgments regarding understanding, and was not previously considered from a metacognitive perspective. Undergraduate students faced difficult problems. They then studied solution explanations with or without uninformative illustrations and provided judgments of comprehension (JCOMPs). Learning was assessed by application to near-transfer problems in an open-book test format. As expected, JCOMPs were polarized - they tended to reflect good or poor understanding. Yet, JCOMPs were higher for the illustrated solutions and even high certainty did not ensure resistance to this effect. Moreover, success in the transfer problems was lower in the presence of illustrations, demonstrating a bias stronger than that found with expository texts. Previous studies have suggested that weak learners are especially prone to being misled by superficial cues. In the present study, matching the difficulty of the task to the ability of the target population revealed that even highly able participants were not immune to misleading cues. The study extends previous findings regarding potential detrimental effects of illustrations and highlights aspects of the metacomprehension process that have not been considered before.

  4. The exact fundamental solution for the Benes tracking problem

    Balaji, Bhashyam


    The universal continuous-discrete tracking problem requires the solution of a Fokker-Planck-Kolmogorov forward equation (FPKfe) for an arbitrary initial condition. Using results from quantum mechanics, the exact fundamental solution for the FPKfe is derived for the state model of arbitrary dimension with Benes drift that requires only the computation of elementary transcendental functions and standard linear algebra techniques- no ordinary or partial differential equations need to be solved. The measurement process may be an arbitrary, discrete-time nonlinear stochastic process, and the time step size can be arbitrary. Numerical examples are included, demonstrating its utility in practical implementation.

  5. A Solution Method for Large Deformation Contact Problems.


    number) Contact Problem Algorithm Implicit Solution Technique 20. ANSTNACT’ (rntftae r eves aIi N yaeemy mrd identify by block numnber) P. solution...WITHOUT oL0 H! 0-CONTACT ALGORITHM Z w 00 0 ev 0.8- w kL 0.0 0 U< O0.26 U)_ * z Z OBTINE 0H53 56 59 ANGE,4 Ficure~~~~~ ~*A G RI H 17 Peitdtatoso iesi itrae...41, Division of Applied Sciences, Harvard Univ., March 1983. [20] Rabinowicz , E., Friction and Wear of Materials, J. Wiley and Sons, 1965. [21

  6. Combinatorial optimization problem solution based on improved genetic algorithm

    Zhang, Peng


    Traveling salesman problem (TSP) is a classic combinatorial optimization problem. It is a simplified form of many complex problems. In the process of study and research, it is understood that the parameters that affect the performance of genetic algorithm mainly include the quality of initial population, the population size, and crossover probability and mutation probability values. As a result, an improved genetic algorithm for solving TSP problems is put forward. The population is graded according to individual similarity, and different operations are performed to different levels of individuals. In addition, elitist retention strategy is adopted at each level, and the crossover operator and mutation operator are improved. Several experiments are designed to verify the feasibility of the algorithm. Through the experimental results analysis, it is proved that the improved algorithm can improve the accuracy and efficiency of the solution.

  7. A Novel Solution to the ATT48 Benchmark Problem

    Ruffa, Anthony A


    A solution to the benchmark ATT48 Traveling Salesman Problem (from the TSPLIB95 library) results from isolating the set of vertices into ten open-ended zones with nine lengthwise boundaries. In each zone, a minimum-length Hamiltonian Path (HP) is found for each combination of boundary vertices, leading to an approximation for the minimum-length Hamiltonian Cycle (HC). Determination of the optimal HPs for subsequent zones has the effect of automatically filtering out non-optimal HPs from earlier zones. Although the optimal HC for ATT48 involves only two crossing edges between all zones (with one exception), adding inter-zone edges can accommodate more complex problems.

  8. Solution of magnetometry problems related to monitoring remote pipeline systems

    Sergeev, Andrey V.; Denisov, Alexey Y.; Narkhov, Eugene D.; Sapunov, Vladimir A.


    The purpose of this paper is to solve two fundamental tasks, i.e., to design the pipeline model with sufficient adequacy and reproducibility, and to solve the inverse problem for the transition from the experimental data on the magnetic field in the measurement area directly to the pipeline characteristics, which are necessary for mapping pipes location and finding coordinates of welds. The paper presents a mathematical ideal pipeline model in the geomagnetic field without considering the pipe material. The solution of the direct and inverse problems are described, and the directions of the model development and methods of data interpretation are presented.

  9. Software Configuration Management Problems and Solutions to Software Variability Management

    Bendix, Lars Gotfred


    These days more and more software is produced as product families. Products that have a lot in common, but all the same vary slightly in one or more aspects. Developing and maintaining these product families is a complex task. Software configuration management (SCM) can, in general, support...... the development and evolution of one single software product and to some degree also supports the concept of variants. It would be interesting to explore to what degree SCM already has solutions to some of the problems of product families and what are the problems where SCM has to invent new techniques to support...

  10. Multiresolution strategies for the numerical solution of optimal control problems

    Jain, Sachin

    There exist many numerical techniques for solving optimal control problems but less work has been done in the field of making these algorithms run faster and more robustly. The main motivation of this work is to solve optimal control problems accurately in a fast and efficient way. Optimal control problems are often characterized by discontinuities or switchings in the control variables. One way of accurately capturing the irregularities in the solution is to use a high resolution (dense) uniform grid. This requires a large amount of computational resources both in terms of CPU time and memory. Hence, in order to accurately capture any irregularities in the solution using a few computational resources, one can refine the mesh locally in the region close to an irregularity instead of refining the mesh uniformly over the whole domain. Therefore, a novel multiresolution scheme for data compression has been designed which is shown to outperform similar data compression schemes. Specifically, we have shown that the proposed approach results in fewer grid points in the grid compared to a common multiresolution data compression scheme. The validity of the proposed mesh refinement algorithm has been verified by solving several challenging initial-boundary value problems for evolution equations in 1D. The examples have demonstrated the stability and robustness of the proposed algorithm. The algorithm adapted dynamically to any existing or emerging irregularities in the solution by automatically allocating more grid points to the region where the solution exhibited sharp features and fewer points to the region where the solution was smooth. Thereby, the computational time and memory usage has been reduced significantly, while maintaining an accuracy equivalent to the one obtained using a fine uniform mesh. Next, a direct multiresolution-based approach for solving trajectory optimization problems is developed. The original optimal control problem is transcribed into a

  11. Existence theorems of solution to variational inequality problems

    ZHANG; Liping


    [1]Harker, P. T., Pang, J. S., Finite-dimensional variational inequality and nonlinear complementarity problems: A survey of theory, algorithm, and applications, Mathematical Programming, 1990, 48(2): 161.[2]Eaves, B. C., The linear complementarity problem, Management Science, 1971, 17(3): 612.[3]Eaves, B. C., On the basic theorem of complementarity problem, Math. Programming, 1971, 1(1): 68.[4]Karamardian, S., Generalized complementarity problem, J. Optim. Theory Appl., 1971, 8(1): 161.[5]Kojima, M., A unification of the existence theorems of the nonlinear complementarity problem, Math. Programming, 1975, 9(2): 257.[6]Moré, J. J., Classes of functions and feasibility conditions in nonlinear complementarity problems, Math. Programming, 1974, 6(2): 327.[7]Moré, J. J., Coercivity conditions in nonlinear complementarity problems, SIAM Rev., 1974, 16(1): 1.[8]Smith, T. E., A solution condition for complementarity problems, with an application to spatial price equilibrium, Appl. Math. Computation, 1984, 15(1): 61.[9]Isac, G., Bulavaski, V., Kalashnikov, V., Exceptional families, topological degree and complementarity problems, J. Global Optim., 1997, 10(2): 207.[10]Zhao, Y. B., Han, J. Y., Qi, H. D., Exceptional families and existence theorems for variational inequality problems, J. Optim. Theory Appl., 1999, 101(2): 475.[11]Zhao, Y. B., Han, J. Y., Exceptional family of elements for a variational inequality problem and its applications, Journal of Global Optimization, 1999, 14(2): 313.[12]Zhao, Y. B., Exceptional families and finite dimensional variational inequalities over polyhedral convex sets, Appl. Math. Computation, 1997, 87(1): 111.[13]Lloyd, N. Q., Degree Theory, Cambridge: Cambridge University Press, 1978, 6—54.[14]Ortega, J. M., Rheinholdt, W. C., Iterative Solution of Nonlinear Equations in Several Variables, New York: Academic Press, 1970, 30—45.[15]Isac, G., Obuchowska, W. T., Functions

  12. Effects of ion exchange on stream solute fluxes in a basin receiving highway deicing salts

    Shanley, J.B.


    At Fever Brook, a 1260-ha forested basin in central Massachusetts, highway deicing salt application increased the solute flux in streamflow by 120% above background flux (equivalent basis) during a 2-yr period. Attempts to isolate the nonsalt component of stream solute fluxes have commonly subtracted salt contributions based on the net Cl flux (Cl output in streamflow minus Cl input in precipitation). In these studies, any net Na flux in excess of the amount needed to balance the net Cl flux has been attributed to weathering. At Fever Brook, however, the net output of Na was less than the net output of Cl, suggesting a loss of Na within the basin. The Na sink was inferred to be cation exchange of Na for Ca and Mg in the soil. A method was developed to quantify the exchange based on a Na budget, which included an independent estimate of the Na flux from weathering. The amount of exchange was apportioned to Ca and Mg based on their relative concentrations in the stream. The background fluxes of Ca and Mg (i.e., those that would occur in the absence of deicing salts) were calculated by subtracting the amounts from ion exchange plus the much smaller direct contributions in deicing salts from the observed fluxes. Ion exchange and direct salt contributions increased the net output fluxes of Ca and Mg, each by 44% above background. In basins that receive deicing salts, failure to account for cation exchange thus may result in an underestimate of the flux of Na from weathering and overestimates of the fluxes of Ca and Mg from weathering.

  13. A stochastic total least squares solution of adaptive filtering problem.

    Javed, Shazia; Ahmad, Noor Atinah


    An efficient and computationally linear algorithm is derived for total least squares solution of adaptive filtering problem, when both input and output signals are contaminated by noise. The proposed total least mean squares (TLMS) algorithm is designed by recursively computing an optimal solution of adaptive TLS problem by minimizing instantaneous value of weighted cost function. Convergence analysis of the algorithm is given to show the global convergence of the proposed algorithm, provided that the stepsize parameter is appropriately chosen. The TLMS algorithm is computationally simpler than the other TLS algorithms and demonstrates a better performance as compared with the least mean square (LMS) and normalized least mean square (NLMS) algorithms. It provides minimum mean square deviation by exhibiting better convergence in misalignment for unknown system identification under noisy inputs.

  14. Solution of MHD problems with mixed-type boundary conditions

    Antimirov, M.IA.


    The introduction of artificial anisotropy of the dynamic viscosity in one of the subregions in which the solution is sought is utilized to derive an approximation method for MHD problems with mixed-type boundary conditions. The method is demonstrated through two problems: slow rotation of a disk and motion of a finite-width infinitely long plate in an infinite volume of a conducting fluid. The velocity and magnetic field solutions are obtained in the form of integrals of Bessel functions, and the torque is found. It is shown that when the Hartmann number approaches infinity the torque of a convex body of revolution in a longitudinal magnetic field is equal to that of a disk lying at the centerline section of the body.


    DING Hao-jiang; JIANG Ai-min


    For the orthotropic piezoelectric plane problem, a series of piezoelectric beams is solved and the corresponding analytical solutions are obtained with the trialand-error method on the basis of the general solution in the case of three distinct eigenvalues, in which all displacements, electrical potential, stresses and electrical displacements are expressed by three displacement functions in terms of harmonic polynomials. These problems are cantilever beam with cross force and point charge at free end, cantilever beam and simply-supported beam subjected to uniform loads on the upper and lower surfaces, and cantilever beam subjected to linear electrical potential.

  16. To Solution of Ecological Problems in Power Systems /

    A. M. Gashimov


    Full Text Available The paper analyses a possibility to minimize damage due to operation of power systems using fossil fuels. Technological schemes of purification processes ensuring efficient  solution of  the ecological problem, particularly, in the case of power station operating on natural gas and fuel oil  are proposed in the paper. The paper contains an analysis of the mechanism in respect of processes occurring in the proposed methods for gas and liquid purification against detrimental impurities.

  17. Explicit solution for an infinite dimensional generalized inverse eigenvalue problem

    Kazem Ghanbari


    Full Text Available We study a generalized inverse eigenvalue problem (GIEP, Ax=λBx, in which A is a semi-infinite Jacobi matrix with positive off-diagonal entries ci>0, and B= diag (b0,b1,…, where bi≠0 for i=0,1,…. We give an explicit solution by establishing an appropriate spectral function with respect to a given set of spectral data.

  18. Electrical circuits in biomedical engineering problems with solutions

    Keskin, Ali Ümit


    This authored monograph presents a comprehensive and in-depth analysis of electrical circuit theory in biomedical engineering, ideally suited as textbook for a course program. The book contains methods and theory, but the topical focus is placed on practical applications of circuit theory, including problems, solutions and case studies. The target audience primarily comprises researchers and experts in electrical engineering who intend to embark on biomedical applications. The book is also very well suited for graduate students in the field. .

  19. On the difference between solutions of discrete tomography problems II

    van Dalen, Birgit


    We consider the problem of reconstructing binary images from their horizontal and vertical projections. It is known that the projections do not necessarily determine the image uniquely. In a previous paper it was shown that the symmetric difference between two solutions (binary images that satisfy the projections) is at most 4A times the square root of 2N. Here N is the sum of the projections in one direction (i.e. the size of the image) and A is a parameter depending on the projections. In this paper we give a lower bound: for each set of projections that has at least two solutions, we construct two solutions that have a symmetric difference of at least 2A+2. We also show that this is the best possible.

  20. SPMH: A Solution to the Problem of Malicious Hosts

    周冲; 孙永强


    In this paper, a solution to the Problem of Malicious Hosts, named SPMH, issuggested. At first, Mobile Agent Blackbox Construction Method based on Loureiro's Protocol(MABCM-LP) is suggested to convert a mobile agent into a Mobile Agent Blackbox (MAB)which makes the mobile agent difficult to be understood and tampered by malicious hosts.At the same time, a Protocol Tracing the Inputs/outputs and Results (PTIR) is developed totrace the mobile agent running at a host, which can be used to detect and prove the attacks bymalicious hosts. It is proved that this solution is secure, correct, and robust. It is found firstlythat the detection method and the prevention method are complementary to each other, andthis is the first solution that integrated both of these two methods too.

  1. Four-Neutrino Oscillation Solutions of the Solar Neutrino Problem

    Giunti, C; Peña-Garay, C


    We present an analysis of the neutrino oscillation solutions of the solar neutrino problem in the framework of four-neutrino mixing where a sterile neutrino is added to the three standard ones. We perform a fit to the full data set corresponding to the 825-day Super-Kamiokande data sample as well as to Chlorine, GALLEX and SAGE and Kamiokande experiments. In our analysis we use all measured total event rates as well as all Super-Kamiokande data on the zenith angle dependence and the recoil electron energy spectrum. We consider both transitions via the Mikheyev-Smirnov-Wolfenstein (MSW) mechanism as well as oscillations in vacuum (just-so) and find the allowed solutions for different values of the additional mixing angles. This framework permits transitions into active or sterile neutrinos controlled by the additional parameter $\\cos^2(\\vartheta_{23}) \\cos^2(\\vartheta_{24})$ . We discuss the maximum allowed values of this additional mixing parameter for the different solutions.

  2. Reduction the secular solution to the periodic solution in the generalized restricted three-body problem

    Abouelmagd, Elbaz I; Elzayat, E M A; Abbas, Ibrahim A


    The aim of the present work is to reduce the secular solution around the triangular equilibrium points to periodic solution in the frame work of the generalized restricted thee-body problem. This model is generalized in sense that both the primaries are oblate and radiating as well as the gravitational potential from a belt. We show that the linearized equation of motion of the infinitesimal body around the triangular equilibrium points has a secular solution when the value of mass ratio equals the critical mass value. Moreover, we reduce this solution to periodic solution, as well as some numerical and graphical investigations for the effects of the perturbed forces are introduced. This model can be used to examine the existence of a dust particle near the triangular points of an oblate and radiating binary stars system surrounded by a belt.

  3. Photoelectron spectroscopy of aqueous solutions: streaming potentials of NaX (X = Cl, Br, and I) solutions and electron binding energies of liquid water and X-.

    Kurahashi, Naoya; Karashima, Shutaro; Tang, Ying; Horio, Takuya; Abulimiti, Bumaliya; Suzuki, Yoshi-Ichi; Ogi, Yoshihiro; Oura, Masaki; Suzuki, Toshinori


    The streaming potentials of liquid beams of aqueous NaCl, NaBr, and NaI solutions are measured using soft X-ray, He(I), and laser multiphoton ionization photoelectron spectroscopy. Gaseous molecules are ionized in the vicinity of liquid beams and the photoelectron energy shifts are measured as a function of the distance between the ionization point and the liquid beam. The streaming potentials change their polarity with concentration of electrolytes, from which the singular points of concentration eliminating the streaming potentials are determined. The streaming currents measured in air also vanish at these concentrations. The electron binding energies of liquid water and I(-), Br(-), and Cl(-) anions are revisited and determined more accurately than in previous studies.

  4. Corrosion problems and solutions in oil refining and petrochemical industry

    Groysman, Alec


    This book addresses corrosion problems and their solutions at facilities in the oil refining and petrochemical industry, including cooling water and boiler feed water units. Further, it describes and analyzes corrosion control actions, corrosion monitoring, and corrosion management. Corrosion problems are a perennial issue in the oil refining and petrochemical industry, as they lead to a deterioration of the functional properties of metallic equipment and harm the environment – both of which need to be protected for the sake of current and future generations. Accordingly, this book examines and analyzes typical and atypical corrosion failure cases and their prevention at refineries and petrochemical facilities, including problems with: pipelines, tanks, furnaces, distillation columns, absorbers, heat exchangers, and pumps. In addition, it describes naphthenic acid corrosion, stress corrosion cracking, hydrogen damages, sulfidic corrosion, microbiologically induced corrosion, erosion-corrosion, and corrosion...

  5. A solution to the decompactification problem in chiral heterotic strings

    Ioannis Florakis


    Full Text Available We present a solution to the decompactification problem of gauge thresholds in chiral heterotic string theories with two large extra dimensions, where supersymmetry is spontaneously broken by the Scherk–Schwarz mechanism. Whenever the Kaluza–Klein scale that controls supersymmetry breaking is much lower than the string scale, the infinite towers of heavy states contribute non-trivially to the renormalisation of gauge couplings, which typically grow linearly with the large volume of the internal space and invalidate perturbation theory. We trace the origin of the decompactification problem to properties of the six dimensional theory obtained in the infinite volume limit and show that thresholds may instead exhibit logarithmic volume dependence and we provide the conditions for this to occur. We illustrate this mechanism with explicit string constructions where the decompactification problem does not occur.

  6. A Weak Solution of a Stochastic Nonlinear Problem

    M. L. Hadji


    Full Text Available We consider a problem modeling a porous medium with a random perturbation. This model occurs in many applications such as biology, medical sciences, oil exploitation, and chemical engineering. Many authors focused their study mostly on the deterministic case. The more classical one was due to Biot in the 50s, where he suggested to ignore everything that happens at the microscopic level, to apply the principles of the continuum mechanics at the macroscopic level. Here we consider a stochastic problem, that is, a problem with a random perturbation. First we prove a result on the existence and uniqueness of the solution, by making use of the weak formulation. Furthermore, we use a numerical scheme based on finite differences to present numerical results.

  7. A solution to the decompactification problem in chiral heterotic strings

    Florakis, Ioannis; Rizos, John


    We present a solution to the decompactification problem of gauge thresholds in chiral heterotic string theories with two large extra dimensions, where supersymmetry is spontaneously broken by the Scherk-Schwarz mechanism. Whenever the Kaluza-Klein scale that controls supersymmetry breaking is much lower than the string scale, the infinite towers of heavy states contribute non-trivially to the renormalisation of gauge couplings, which typically grow linearly with the large volume of the internal space and invalidate perturbation theory. We trace the origin of the decompactification problem to properties of the six dimensional theory obtained in the infinite volume limit and show that thresholds may instead exhibit logarithmic volume dependence and we provide the conditions for this to occur. We illustrate this mechanism with explicit string constructions where the decompactification problem does not occur.

  8. Methods of using the quadratic assignment problem solution

    Izabela Kudelska


    Full Text Available Background: Quadratic assignment problem (QAP is one of the most interesting of combinatorial optimization. Was presented by Koopman and Beckamanna in 1957, as a mathematical model of the location of indivisible tasks. This problem belongs to the class NP-hard issues. This forces the application to the solution already approximate methods for tasks with a small size (over 30. Even though it is much harder than other combinatorial optimization problems, it enjoys wide interest because it models the important class of decision problems. Material and methods: The discussion was an artificial intelligence tool that allowed to solve the problem QAP, among others are: genetic algorithms, Tabu Search, Branch and Bound. Results and conclusions: QAP did not arise directly as a model for certain actions, but he found its application in many areas. Examples of applications of the problem is: arrangement of buildings on the campus of the university, layout design of electronic components in systems with large scale integration (VLSI, design a hospital, arrangement of keys on the keyboard.

  9. Analysis and Numerical Solutions of Positive and Dead Core Solutions of Singular Sturm-Liouville Problems

    Gernot Pulverer


    Full Text Available In this paper, we investigate the singular Sturm-Liouville problem u′′=λg(u, u′(0=0, βu′(1+αu(1=A, where λ is a nonnegative parameter, β≥0, α>0, and A>0. We discuss the existence of multiple positive solutions and show that for certain values of λ, there also exist solutions that vanish on a subinterval [0,ρ]⊂[0,1, the so-called dead core solutions. The theoretical findings are illustrated by computational experiments for g(u=1/u and for some model problems from the class of singular differential equations (ϕ(u′′+f(t,u′=λg(t,u,u′ discussed in Agarwal et al. (2007. For the numerical simulation, the collocation method implemented in our MATLAB code bvpsuite has been applied.

  10. Solution and its application of transient stream/groundwater model subjected to time-dependent vertical seepage


    Based on the first linearized Boussinesq equation, the analytical solution of the transient groundwater model, which is used for describing phreatic flow in a semiinfinite aquifer bounded by a linear stream and subjected to time-dependent vertical seepage, is derived out by Laplace transform and the convolution integral.According to the mathematical characteristics of the solution, different methods for estimating aquifer parameters are constructed to satisfy different hydrological conditions.Then, the equation for estimating water exchange between stream and aquifer is proposed, and a recursion equation or estimating the intensity of phreatic evaporation is also proposed.A phreatic aquifer stream system located in Huaibei Plain, Anhui Province, China, is taken as an example to demonstrate the estimation process of the methods stated herein.

  11. North Dakota's Centennial Quilt and Problem Solvers: Solutions: The Library Problem

    Small, Marian


    Quilt investigations, such as the Barn quilt problem in the December 2008/January 2009 issue of "Teaching Children Mathematics" and its solutions in last month's issue, can spark interdisciplinary pursuits for teachers and exciting connections for the full range of elementary school students. This month, North Dakota's centennial quilt…


    O. A. Mosinа


    Full Text Available In article questions of forming of the socializing e nvironment with use of educational potential of inte rgenerational interaction are considered. The modern Russian family is under considerable social and economic pressure, without having an opportunity, in most cases, fully to be engaged in education of children. As a result of it the number of the problem (deviant teenagers requiring systematic psychology and pedagogical impact increases. Educational inst itutions and centers for the objective reasons (sta ff deficit; the growing number of the children needing attention; economic difficulties, etc. not always can help the child to overcome difficult conditions of activity, to support, protect, rehabilitate. Authors of article propose  the possible solution  o f  the designated problem in installation in traditional model of the educational environment of educational instit utions  of  practice  of  inter-generational  interaction. The competent volunteer can be one of solutions of this task. According to authors, elderly people who have retired and have interrupted the vigorous labor activity are capable to perform a role of volunteers, but  have  the  corresponding  education  and  a  ps ychology and pedagogical work experience. Besides, having had special training, such people will be able to work with  the children having problems in  ps ychological or ethical development.

  13. Novel Problem Solving - The NASA Solution Mechanism Guide

    Keeton, Kathryn E.; Richard, Elizabeth E.; Davis, Jeffrey R.


    Over the past five years, the Human Health and Performance (HH&P) Directorate at the NASA Johnson Space Center (JSC) has conducted a number of pilot and ongoing projects in collaboration and open innovation. These projects involved the use of novel open innovation competitions that sought solutions from "the crowd", non-traditional problem solvers. The projects expanded to include virtual collaboration centers such as the NASA Human Health and Performance Center (NHHPC) and more recently a collaborative research project between NASA and the National Science Foundation (NSF). These novel problem-solving tools produced effective results and the HH&P wanted to capture the knowledge from these new tools, to teach the results to the directorate, and to implement new project management tools and coursework. The need to capture and teach the results of these novel problem solving tools, the HH&P decided to create a web-based tool to capture best practices and case studies, to teach novice users how to use new problem solving tools and to change project management training/. This web-based tool was developed with a small, multi-disciplinary group and named the Solution Mechanism Guide (SMG). An alpha version was developed that was tested against several sessions of user groups to get feedback on the SMG and determine a future course for development. The feedback was very positive and the HH&P decided to move to the beta-phase of development. To develop the web-based tool, the HH&P utilized the NASA Tournament Lab (NTL) to develop the software with TopCoder under an existing contract. In this way, the HH&P is using one new tool (the NTL and TopCoder) to develop the next generation tool, the SMG. The beta-phase of the SMG is planed for release in the spring of 2014 and results of the beta-phase testing will be available for the IAC meeting in September. The SMG is intended to disrupt the way problem solvers and project managers approach problem solving and to increase the

  14. Reach a New Threshold of Freedom and Control with Dell's Flexible Computing Solution: On-Demand Desktop Streaming

    Technology & Learning, 2008


    When it comes to IT, there has always been an important link between data center control and client flexibility. As computing power increases, so do the potentially crippling threats to security, productivity and financial stability. This article talks about Dell's On-Demand Desktop Streaming solution which is designed to centralize complete…

  15. Reach a New Threshold of Freedom and Control with Dell's Flexible Computing Solution: On-Demand Desktop Streaming

    Technology & Learning, 2008


    When it comes to IT, there has always been an important link between data center control and client flexibility. As computing power increases, so do the potentially crippling threats to security, productivity and financial stability. This article talks about Dell's On-Demand Desktop Streaming solution which is designed to centralize complete…

  16. Estimates for mild solutions to semilinear Cauchy problems

    Kresimir Burazin


    Full Text Available The existence (and uniqueness results on mild solutions of the abstract semilinear Cauchy problems in Banach spaces are well known. Following the results of Tartar (2008 and Burazin (2008 in the case of decoupled hyperbolic systems, we give an alternative proof, which enables us to derive an estimate on the mild solution and its time of existence. The nonlinear term in the equation is allowed to be time-dependent. We discuss the optimality of the derived estimate by testing it on three examples: the linear heat equation, the semilinear heat equation that models dynamic deflection of an elastic membrane, and the semilinear Schrodinger equation with time-dependent nonlinearity, that appear in the modelling of numerous physical phenomena.

  17. A Solution Proposal To Indefinite Quadratic Interval Transportation Problem

    Hasan Dalman


    Full Text Available The data of real world applications generally cannot be expressed strictly. An efficient way of handling this situation is expressing the data as intervals. Thus, this paper focus on the Indefinite Quadratic Interval Transportation Problem (IQITP in which all the parameters i.e. cost and risk coefficients of the objective function, supply and demand quantities are expressed as intervals. A Taylor series approach is presented for the solution of IQITP by means of the expression of intervals with its left and right limits. Also a numerical example is executed to illustrate the procedure.

  18. Problems and Solutions of Popularization of Accounting Computerization

    Lu, Kan; Fu, YingLi; Gu, CaiDong; Zhang, Liang

    With the integration of China's economy and international markets, accounting computerization, which conducts accounting and accounting control by taking advantage of computer, has become a major component sector of accounting modernization and the main content of accounting reform. The popularization of accounting computerization is beyond question. Only this popularization can meet the requirement of knowledge economy for accounting information. It is the need to deepen accounting reform, to further enhance the level of accounting work and to achieve China's modernization of science and technology as well. This paper discusses problems and relevant solutions in the popularization process of accounting computerization so as to carry out this popularization better.

  19. Toroidal vortices as a solution to the dust migration problem

    Loren-Aguilar, Pablo


    In an earlier letter, we reported that dust settling in protoplanetary discs may lead to a dynamical dust-gas instability that produces global toroidal vortices. In this letter, we investigate the evolution of a dusty protoplanetary disc with two different dust species (1 mm and 50 cm dust grains), under the presence of the instability. We show how toroidal vortices, triggered by the interaction of mm grains with the gas, stop the radial migration of metre-sized dust, potentially offering a natural and efficient solution to the dust migration problem.

  20. The Problems and Solutions of Learning English Effectively in class



    English, as an international language, is becoming more and more important in our society. Its proficiency has become a major requirement for attaining the highest level of professional and economic success around the world. We, English learners mainly learn English in Classroom, so classroom is regarded as the most important place where we learn English language. This paper gives out an analysis of the problems which lead to the ineffective English learning and discusses the solutions of an effective English learning in class according to the author' s own experience in English teaching in secondary schools and colleges.

  1. Development of solutions to benchmark piping problems. [EPIPE code

    Reich, M.; Chang, T.Y.; Prachuktam, S.


    Piping analysis is one of the most extensive engineering efforts required for the design of nuclear reactors. Such analysis is normally carried out by use of computer programs which can handle complex piping geometries and various loading conditions, (static or dynamic). A brief outline is presented of the theoretical background for the EPIPE program, together with four benchmark problems: two for the static case and two for the dynamic case. The results obtained from EPIPE runs compare well with those available from known analytical solutions or from other independent computer programs.

  2. VEP oscillation solutions to the solar neutrino problem

    Casini, H; Montemayor, R


    We study the solar neutrino problem within the framework of a parametrized post-Newtonian formulation for the gravitational interaction of the neutrinos, which incorporates a violation to the equivalence principle (VEP). Using the current data on the rates and the energy spectrum we find two possible oscillation solutions, both for a large mixing angle. One of them involves the MSW effect in matter and the other corresponds to vacuum oscillations. An interesting characteristic of this mechanism is that it predicts a semi-annual variation of the neutrino flux. Our analysis provides new constraints for some VEP parameters.

  3. Building Science and Technology Solutions for National Problems

    Bishop, Alan R. [Los Alamos National Laboratory


    The nation's investment in Los Alamos has fostered scientific capabilities for national security missions. As the premier national security science laboratory, Los Alamos tackles: (1) Multidisciplinary science, technology, and engineering challenges; (2) Problems demanding unique experimental and computational facilities; and (3) Highly complex national security issues requiring fundamental breakthroughs. Our mission as a DOE national security science laboratory is to develop and apply science, technology, and engineering solutions that: (1) ensure the safety, security, and reliability of the US nuclear deterrent; (2) protect against the nuclear threat; and (3) solve national security challenges.

  4. Continuous dependence of solutions for indefinite semilinear elliptic problems

    Elves A. B. Silva


    Full Text Available We consider the superlinear elliptic problem $$ -\\Delta u + m(xu = a(xu^p $$ in a bounded smooth domain under Neumann boundary conditions, where $m \\in L^{\\sigma}(\\Omega$, $\\sigma\\geq N/2$ and $a\\in C(\\overline{\\Omega}$ is a sign changing function. Assuming that the associated first eigenvalue of the operator $-\\Delta + m $ is zero, we use constrained minimization methods to study the existence of a positive solution when $\\widehat{m}$ is a suitable perturbation of m.

  5. Singularly perturbed hyperbolic problems on metric graphs: asymptotics of solutions

    Golovaty Yuriy


    Full Text Available We are interested in the evolution phenomena on star-like networks composed of several branches which vary considerably in physical properties. The initial boundary value problem for singularly perturbed hyperbolic differential equation on a metric graph is studied. The hyperbolic equation becomes degenerate on a part of the graph as a small parameter goes to zero. In addition, the rates of degeneration may differ in different edges of the graph. Using the boundary layer method the complete asymptotic expansions of solutions are constructed and justified.

  6. Feedback Solution to Optimal Switching Problems With Switching Cost.

    Heydari, Ali


    The problem of optimal switching between nonlinear autonomous subsystems is investigated in this paper where the objective is not only bringing the states to close to the desired point, but also adjusting the switching pattern, in the sense of penalizing switching occurrences and assigning different preferences to utilization of different modes. The mode sequence is unspecified and a switching cost term is used in the cost function for penalizing each switching. It is shown that once a switching cost is incorporated, the optimal cost-to-go function depends on the subsystem which was active at the previous time step. Afterward, an approximate dynamic programming-based method is developed, which provides an approximation of the optimal solution to the problem in a feedback form and for different initial conditions. Finally, the performance of the method is analyzed through numerical examples.

  7. The problems of using credit card and some possible solutions



      The credit card was first used in the 1920s,in the United States,and it has increased steadily. It becomes a worldwide payment method. The credit card provides two basic benefits. The first one is It provides the convenient to the holders for the credit card owners can carry a card instead of a large sum of cash. Moreover,the card-holders are able to purchase some products with this kind of card for it allows the owners to borrow money from bank at some future cost.(Sha Yang 2006)However,because of the imperfect of credit card system(Yingjiu Li 2005), unrealistic optimism in consumer credit card adoption(Sha yang 2006)and APR Trap (Steve Sildon2008),all of these problems cause lots of problems for cardholders. This presentation will consider about the three problems which will bring the trouble to the consumers,and then it will focus on some possible solutions to address these problems for individual users. Finally,the presentation will present some way to make money with credit card.

  8. A Solution to Lithium Problem by Long-Lived Stau

    Sato, Joe; Yamanaka, Masato


    We review a non-standard Big-Bang nucleosynthesis (BBN) scenario within the minimal supersymmetric standard model, and propose an idea to solve both ${}^{7}$Li and ${}^{6}$Li problems. Each problem is a discrepancy between the predicted abundance in the standard BBN and observed one. We focus on the stau, a supersymmetric partner of tau lepton, which is a long-lived charged particle when it is the next lightest supersymmetric particle and is degenerate in mass with the lightest supersymmetric particle. The long-lived stau forms a bound state with a nucleus, and provide non-standard nuclear reactions. One of those, the internal conversion process, accelerates the destruction of ${}^{7}$Be and ${}^{7}$Li, and leads to a solution to the ${}^{7}$Li problem. On the other hand, the bound state of the stau and ${}^{4}$He enhances productions of n, d, t, and ${}^{6}$Li. The over-production of ${}^{6}$Li could solve the ${}^{6}$Li problem. While, the over-productions of d and t could conflict with observations, and th...

  9. Explicit Estimates for Solutions of Mixed Elliptic Problems

    Luisa Consiglieri


    Full Text Available We deal with the existence of quantitative estimates for solutions of mixed problems to an elliptic second-order equation in divergence form with discontinuous coefficients. Our concern is to estimate the solutions with explicit constants, for domains in ℝn (n≥2 of class C0,1. The existence of L∞ and W1,q estimates is assured for q=2 and any qproblem.

  10. A mathematical solution to a network designing problem.

    Takahashi, Y


    One of the major open issues in neural network research includes a Network Designing Problem (NDP): find a polynomial-time procedure that produces minimal structures (the minimum intermediate size, thresholds and synapse weights) of multilayer threshold feed-forward networks so that they can yield outputs consistent with given sample sets of input-output data. The NDP includes as a subproblem a Network Training Problem (NTP) where the intermediate size is given. The NTP has been studied mainly by use of iterative algorithms of network training. This paper, making use of both rate distortion theory in information theory and linear algebra, solves the NDP mathematically rigorously. On the basis of this mathematical solution, it furthermore develops a mathematical solution procedure to the NDP that computes the minimal structure straightforwardly from the sample set. The procedure precisely attains the minimum intermediate size, although its computational time complexity can be of nonpolynomial order at worst cases. The paper also refers to a polynomial-time shortcut of the procedure for practical use that can reach an approximate minimum intermediate size with its error measurable. The shortcut, when the intermediate size is prespecified, reduces to a promising alternative as well to current network training algorithms to the NTP.

  11. Status of the MSW Solutions of the Solar Neutrino Problem

    González-Garciá, M Concepción; Peña-Garay, C; Valle, José W F


    We present an updated global analysis of two-flavor MSW solutions to the solar neutrino problem in terms of conversions of nu_e into active or sterile neutrinos. We perform a fit to the full data set corresponding to the 708-day Super-Kamiokande data sample as well as to Chlorine, GALLEX and SAGE experiments. We use all measured total event rates as well as Super-Kamiokande data on the zenith angle dependence, energy spectrum and seasonal variation of the events. For conversions into active neutrinos we find that, although the data on the total event rates favours the Small Mixing Angle (SMA) solution, once the full data set is included both SMA and Large Mixing Angle (LMA) solutions give an equivalent fit to the data. The best-fit points for the combined analysis are Delta m^2=3.6 10^{-5} eV^2 sin^2(2theta)=0.8 with chi^2_min=36.3/30 d.o.f and Delta m^2=6.3~ 10^{-6} eV^2 and sin^2(2theta)=4.5 10^{-3} with chi^2_min=37.7/30 d.o.f. In contrast with the earlier 504-day study of Bahcall-Krastev-Smirnov our resul...

  12. Stability of Solutions to Classes of Traveling Salesman Problems.

    Niendorf, Moritz; Kabamba, Pierre T; Girard, Anouck R


    By performing stability analysis on an optimal tour for problems belonging to classes of the traveling salesman problem (TSP), this paper derives margins of optimality for a solution with respect to disturbances in the problem data. Specifically, we consider the asymmetric sequence-dependent TSP, where the sequence dependence is driven by the dynamics of a stack. This is a generalization of the symmetric non sequence-dependent version of the TSP. Furthermore, we also consider the symmetric sequence-dependent variant and the asymmetric non sequence-dependent variant. Amongst others these problems have applications in logistics and unmanned aircraft mission planning. Changing external conditions such as traffic or weather may alter task costs, which can render an initially optimal itinerary suboptimal. Instead of optimizing the itinerary every time task costs change, stability criteria allow for fast evaluation of whether itineraries remain optimal. This paper develops a method to compute stability regions for the best tour in a set of tours for the symmetric TSP and extends the results to the asymmetric problem as well as their sequence-dependent counterparts. As the TSP is NP-hard, heuristic methods are frequently used to solve it. The presented approach is also applicable to analyze stability regions for a tour obtained through application of the k -opt heuristic with respect to the k -neighborhood. A dimensionless criticality metric for edges is proposed, such that a high criticality of an edge indicates that the optimal tour is more susceptible to cost changes in that edge. Multiple examples demonstrate the application of the developed stability computation method as well as the edge criticality measure that facilitates an intuitive assessment of instances of the TSP.

  13. A secure multi-party computation solution to intersection problems of sets and rectangles

    LI Shundong; DAI Yiqi; WANG Daoshun; LUO Ping


    Secure multi-party computation (SMC) is a research focus in international cryptographic community. At present, there is no SMC solution to the intersection problem of sets. In this paper, we first propose a SMC solution to this problem. Applying Cantor encoding method to computational geometry problems, and based on the solution to set-intersection problem, we further propose solutions to points inclusion problem and intersection problem of rectangles and further prove their privacy-preserving property with widely accepted simulation paradigm. Compared with the known solutions, these new solutions are of less computational complexity and less communication complexity, and have obvious superiority in computational and communication complexity.


    S. Prakash


    Full Text Available

    ENGLISH ABSTRACT: The Multi-Objective Generalized Assignment Problem (MGAP with two objectives, where one objective is linear and the other one is non-linear, has been considered, with the constraints that a job is assigned to only one worker – though he may be assigned more than one job, depending upon the time available to him. An algorithm is proposed to find the set of Pareto optimal solutions of the problem, determining assignments of jobs to workers with two objectives without setting priorities for them. The two objectives are to minimise the total cost of the assignment and to reduce the time taken to complete all the jobs.

    AFRIKAANSE OPSOMMING: ‘n Multi-doelwit veralgemeende toekenningsprobleem (“multi-objective generalised assignment problem – MGAP” met twee doelwitte, waar die een lineêr en die ander nielineêr is nie, word bestudeer, met die randvoorwaarde dat ‘n taak slegs toegedeel word aan een werker – alhoewel meer as een taak aan hom toegedeel kan word sou die tyd beskikbaar wees. ‘n Algoritme word voorgestel om die stel Pareto-optimale oplossings te vind wat die taaktoedelings aan werkers onderhewig aan die twee doelwitte doen sonder dat prioriteite toegeken word. Die twee doelwitte is om die totale koste van die opdrag te minimiseer en om die tyd te verminder om al die take te voltooi.

  15. Assessing student written problem solutions: A problem-solving rubric with application to introductory physics

    Docktor, Jennifer L.; Dornfeld, Jay; Frodermann, Evan; Heller, Kenneth; Hsu, Leonardo; Jackson, Koblar Alan; Mason, Andrew; Ryan, Qing X.; Yang, Jie


    Problem solving is a complex process valuable in everyday life and crucial for learning in the STEM fields. To support the development of problem-solving skills it is important for researchers and curriculum developers to have practical tools that can measure the difference between novice and expert problem-solving performance in authentic classroom work. It is also useful if such tools can be employed by instructors to guide their pedagogy. We describe the design, development, and testing of a simple rubric to assess written solutions to problems given in undergraduate introductory physics courses. In particular, we present evidence for the validity, reliability, and utility of the instrument. The rubric identifies five general problem-solving processes and defines the criteria to attain a score in each: organizing problem information into a Useful Description, selecting appropriate principles (Physics Approach), applying those principles to the specific conditions in the problem (Specific Application of Physics), using Mathematical Procedures appropriately, and displaying evidence of an organized reasoning pattern (Logical Progression).

  16. Injection, injectivity and injectability in geothermal operations: problems and possible solutions. Phase I. Definition of the problems

    Vetter, O.J.; Crichlow, H.B.


    The following topics are covered: thermodynamic instability of brine, injectivity loss during regular production and injection operations, injectivity loss caused by measures other than regular operations, heat mining and associated reservoir problems in reinjection, pressure maintenance through imported make-up water, suggested solutions to injection problems, and suggested solutions to injection problems: remedial and stimulation measures. (MHR)

  17. On the Dynamical Solution of Quantum Measurement Problem

    Belavkin, V P


    The development of quantum measurement theory, initiated by von Neumann, only indicated a possibility for resolution of the interpretational crisis of quantum mechanics. We do this by divorcing the algebra of the dynamical generators and the algebra of the actual observables, or beables. It is shown that within this approach quantum causality can be rehabilitated in the form of a superselection rule for compatibility of the past beables with the potential future. This rule, together with the self-compatibility of the measurements insuring the consistency of the histories, is called the nondemolition, or causality principle in modern quantum theory. The application of this rule in the form of the dynamical commutation relations leads in particular to the derivation of the von Neumann projection postulate. This gives a quantum stochastic solution, in the form of the dynamical filtering equations, of the notorious measurement problem which was tackled unsuccessfully by many famous physicists starting with Schroe...

  18. Lectures on quantum mechanics with problems, exercises and their solutions

    Basdevant, Jean-Louis


    The new edition of this remarkable text offers the reader a conceptually strong introduction to quantum mechanics, but goes beyond this to present a fascinating tour of modern theoretical physics. Beautifully illustrated and engagingly written, it starts with a brief overview of diverse topics across physics including nanotechnology, statistical physics, materials science, astrophysics, and cosmology. The core of the book covers both established and emerging aspects of quantum mechanics. A concise introduction to traditional quantum mechanics covers the Schrödinger equation, Hilbert space, the algebra of observables, hydrogen atom, spin and Pauli principle. Modern features of the field are presented by exploring entangled states, Bell's inequality, quantum cryptography, quantum teleportation and quantum mechanics in the universe. This new edition has been enchanced through the addition of numerous problems with detailed solutions, an introduction to the mathematical tools needed and expanded discussion of th...

  19. Design as co-evolution of problem, solution, and audience

    Halstrøm, Per Liljenberg; Galle, Per


    The meaning of ‘design’ can be captured in a general way by a good definition, but even the best definition cannot provide an understanding sufficiently deep to guide the professional designer or the student of design in the intricate deliberations of doing design in practice. Therefore we explore...... design beyond the level of definitions, reviewing canonical theories about design as a professional enterprise. We find that the well-established theoretical notion of ‘co-evolution’ of problem and solution in design has its merits in regard to understanding design deliberations; but also that existing...... conceptual resources for conceiving of design in terms of such triple co-evolution. For example, many design products may be thought of as offering an audience a ‘subject position’ that hint at whom they should become. In support of the case we make for thinking in terms of constitutive rhetoric in design...

  20. Asymptotic Solution to the Rayleigh Problem of Dynamic Soaring

    Bousquet, Gabriel D; Slotine, Jean-Jacques E


    It is believed that albatrosses power their flight through dynamic soaring, a technique where energy is extracted from horizontally blowing shear winds. The Rayleigh model of dynamic soaring, also called the two layer model, makes a 2-dimensional approximation of the wind field and glider trajectory. This note considers the "Rayleigh problem" of finding the minimum wind necessary for the existence of energy neutral gliding cycles. We utilize a 3-degree of freedom glider model with quadratic drag. Asymptotic solutions in the limit of large glide ratios are obtained. The optimal motion is a traveling trajectory constituted of a succession of small partial turns. It is over 50% more efficient at preserving airspeed than full half-turn based trajectories.

  1. Problems and solutions in quantum computing and quantum information

    Steeb, Willi-Hans


    Quantum computing and quantum information are two of the fastest growing and most exciting research fields in physics. Entanglement, teleportation and the possibility of using the non-local behavior of quantum mechanics to factor integers in random polynomial time have also added to this new interest. This book supplies a huge collection of problems in quantum computing and quantum information together with their detailed solutions, which will prove to be invaluable to students as well as researchers in these fields. All the important concepts and topics such as quantum gates and quantum circuits, product Hilbert spaces, entanglement and entanglement measures, deportation, Bell states, Bell inequality, Schmidt decomposition, quantum Fourier transform, magic gate, von Neumann entropy, quantum cryptography, quantum error corrections, number states and Bose operators, coherent states, squeezed states, Gaussian states, POVM measurement, quantum optics networks, beam splitter, phase shifter and Kerr Hamilton opera...

  2. A minimalist legislative solution to the problem of euthanasia.

    Komesaroff, Paul A; Charles, Stephen


    Intense debate has continued for many years about whether voluntary euthanasia or assisted suicide should be permitted by law. The community is bitterly divided and there has been vigorous opposition from medical practitioners and the Australian Medical Association. Despite differences of religious and philosophical convictions and ethical values, there is widespread community agreement that people with terminal illnesses are entitled to adequate treatment, and should also be allowed to make basic choices about when and how they die. A problem with the current law is that doctors who follow current best practice cannot be confident that they will be protected from criminal prosecution. We propose simple changes to Commonwealth and state legislation that recognise community concerns and protect doctors acting in accordance with best current practice. This minimalist solution should be widely acceptable to the community, including both the medical profession and those who object to euthanasia for religious reasons. Important areas of disagreement will persist that can be addressed in future debates.

  3. Problems and solutions in laboratory testing for hemophilia.

    Favaloro, Emmanuel J; Meijer, Piet; Jennings, Ian; Sioufi, John; Bonar, Roslyn A; Kitchen, Dianne P; Kershaw, Geoffrey; Lippi, Giuseppe


    A diagnosis of hemophilia A or hemophilia B begins with clinical assessment of the patient and is facilitated by laboratory testing. The influence of the latter on a diagnosis of hemophilia A or hemophilia B is clear-a diagnosis cannot be made without laboratory confirmation of a deficiency of factor FVIII (FVIII) or factor IX (FIX), respectively. Moreover, the degree of hemophilia severity is specifically characterized by laboratory test results. In turn, patient management, including choice and application of therapies, is influenced by the diagnosis, as well as by identification of respective disease severity. An incorrect diagnosis may lead to inappropriate management and unnecessary therapy, and thus to adverse outcomes. Moreover, identification of factor inhibitors in hemophilia will lead to additional and differential treatments, and incorrect identification of inhibitors or inhibitor levels may also lead to inappropriate management. Problems in hemophilia diagnosis or inhibitor detection can occur at any stage in the clinical diagnosis/laboratory interface, from the "pre-preanalytical" to "preanalytical" to "analytical" to "postanalytical" to "post-postanalytical." This report outlines the various problems in laboratory testing for hemophilia and provides various strategies or solutions to overcome these challenges. Although some outlined solutions are specific to the potential errors related to hemophilia, others are general in nature and can be applied to other areas of laboratory hemostasis. Key to improvement in this area is adoption of best practice by all involved, including clinicians, phlebotomists, and laboratories. Also key is the recognition that such errors may occur, and thus that clinicians should assess laboratory test results in the context of their patient's clinical history and follow-up any potential errors, thus avoid misdiagnoses, by requesting repeat testing on a fresh sample.

  4. Solute transport in streams of varying morphology inferred from a high resolution network of potentiometric wireless chloride sensors

    Klaus, Julian; Smettem, Keith; Pfister, Laurent; Harris, Nick


    There is ongoing interest in understanding and quantifying the travel times and dispersion of solutes moving through stream environments, including the hyporheic zone and/or in-channel dead zones where retention affects biogeochemical cycling processes that are critical to stream ecosystem functioning. Modelling these transport and retention processes requires acquisition of tracer data from injection experiments where the concentrations are recorded downstream. Such experiments are often time consuming and costly, which may be the reason many modelling studies of chemical transport have tended to rely on relatively few well documented field case studies. This leads to the need of fast and cheap distributed sensor arrays that respond instantly and record chemical transport at points of interest on timescales of seconds at various locations in the stream environment. To tackle this challenge we present data from several tracer experiments carried out in the Attert river catchment in Luxembourg employing low-cost (in the order of a euro per sensor) potentiometric chloride sensors in a distributed array. We injected NaCl under various baseflow conditions in streams of different morphologies and observed solute transport at various distances and locations. This data is used to benchmark the sensors to data obtained from more expensive electrical conductivity meters. Furthermore, the data allowed spatial resolution of hydrodynamic mixing processes and identification of chemical 'dead zones' in the study reaches.

  5. Truncated VSV solutions to symmetric rank-deficient problems

    Fierro, Richardo D.; Hansen, Per Christian


    Symmetric VSV decompositions are new rank-revealing decompositions that exploit and preserve symmetry. Truncated VSV solutions are stabilized solutions computed by neglecting blocks in the VSV decomposition with small norm. We compare the truncated VSV solutions with truncated SVD solutions...... and give perturbation bounds for the VSV solutions. Numerical examples illustrate our results....

  6. Truncated VSV Solutions to Symmetric Rank-Deficient Problems

    Fierro, Ricardo D.; Hansen, Per Christian


    Symmetric VSV decompositions are new rank-revealing decompositions that exploit and preserve symmetry. Truncated VSV solutions are stabilized solutions computed by neglecting blocks in the VSV decomposition with small norm. We compare the truncated VSV solutions with truncated SVD solutions...... and give perturbation bounds for the VSV solutions. Numerical examples illustrate our results....

  7. Dynamical phase coexistence: A simple solution to the "savanna problem"

    Vazquez, F; Calabrese, J M; Munoz, M A; 10.1016/j.jtbi.2010.02.011


    We introduce the concept of 'dynamical phase coexistence' to provide a simple solution for a long-standing problem in theoretical ecology, the so-called "savanna problem". The challenge is to understand why in savanna ecosystems trees and grasses coexist in a robust way with large spatio-temporal variability. We propose a simple model, a variant of the Contact Process (CP), which includes two key extra features: varying external (environmental/rainfall) conditions and tree age. The system fluctuates locally between a woodland and a grassland phase, corresponding to the active and absorbing phases of the underlying pure contact process. This leads to a highly variable stable phase characterized by patches of the woodland and grassland phases coexisting dynamically. We show that the mean time to tree extinction under this model increases as a power-law of system size and can be of the order of 10,000,000 years in even moderately sized savannas. Finally, we demonstrate that while local interactions among trees m...

  8. Standard physics solution to the solar neutrino problem?

    Dar, A. [Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics


    The {sup 8}B solar neutrino flux predicted by the standard solar model (SSM) is consistent within the theoretical and experimental uncertainties with that at Kamiokande. The Gallium and Chlorine solar neutrino experiments, however, seem to imply that the {sup 7}Be solar neutrino flux is strongly suppressed compared with that predicted by the SSM. If the {sup 7}Be solar neutrino flux is suppressed, still it can be due to astrophysical effects not included in the simplistic SSM. Such effects include short term fluctuations or periodic variation of the temperature in the solar core, rotational mixing of {sup 3}He in the solar core, and dense plasma effects which may strongly enhance p-capture by {sup 7}Be relative to e-capture. The new generation of solar observations which already look non stop deep into the sun, like Superkamiokande through neutrinos, and SOHO and GONG through acoustic waves, may point at the correct solution. Only Superkamiokande and/or future solar neutrino experiments, such as SNO, BOREXINO and HELLAZ, will be able to find out whether the solar neutrino problem is caused by neutrino properties beyond the minimal standard electroweak model or whether it is just a problem of the too simplistic standard solar model. (author) 1 fig., 3 tabs., refs.

  9. Fast solutions for UC problems by a new metaheuristic approach

    Viana, Ana; de Sousa, J. Pinho; Matos, Manuel A. [INESC Porto, Campus da FEUP, Rua Dr. Roberto Frias 378, 4200-465 Porto (Portugal)


    Due to its combinatorial nature, the Unit Commitment problem has for long been an important research challenge, with several optimization techniques, from exact to heuristic methods, having been proposed to deal with it. In line with one current trend of research, metaheuristic approaches have been studied and some interesting results have already been achieved and published. However, a successful utilization of these methodologies in practice, when embedded in Energy Management Systems, is still constrained by the reluctance of industrial partners in using techniques whose performance highly depends on a correct parameter tuning. Therefore, the application of metaheuristics to the Unit Commitment problem does still justify further research. In this paper we propose a new search strategy, for Local Search based metaheuristics, that tries to overcome this issue. The approach has been tested in a set of instances, leading to very good results in terms of solution cost, when compared either to the classical Lagrangian Relaxation or to other metaheuristics. It also drastically reduced the computation times. Furthermore, the approach proved to be robust, always leading to good results independently of the metaheuristic parameters used. (author)

  10. New Solutions for Instant Payment Problems in Indonesia

    Bambang Robi'in


    Full Text Available Instant payment is a growing payment method in e-commerce in Indonesia. These service providers are generally national banks. Technically instant payment services is web services or APIs provided by the Bank to access e-commerce applications belong to a merchant or marketplace when the buyer wants to make a payment. A problem sometimes arises when the payment transaction is done at the payment gateway but did not succeed in the transaction status update section e-commerce applications. One of the causes of this failure is the internet connection is not stable. This condition causes the customer to the bank acount balance is reduced but the purchase transaction in the status of unpaid. Methods of research conducted through three stages of data collection and analysis, schematic design solutions, and evaluation.In the interview we found that 4 out of 10 people we interviewed using the instant payment has experienced such failures, to improve the condition necessary a mechanisms troublesome and takes a long time. This papper propose a payment scheme with an additional mechanism to resolve the issue. The results showed that the scheme proposed in this study has a good performance in overcoming the problem of instant payment.

  11. A priori estimates for global solutions and multiple equilibria of a superlinear parabolic problem involving measures

    Pavol Quittner


    Full Text Available We consider a noncoercive elliptic problem in a bounded domain with a power nonlinearity and measure data. It is known that the problem possesses a stable solution and we prove existence of three further solutions. The proof is based on uniform bounds of global solutions of the corresponding parabolic problem and on a topological degree argument.


    Cheng Ouyang


    A class of semi-linear Robin problem is considered. Under appropriate assumptions, the existence and asymptotic behavior of its solution are studied more carefully. Using stretched variables, the formal asymptotic expansion of solution for the problem is constructed and the uniform validity of the solution is obtained by using the method of upper and lower solution.

  13. On the relationship of transient storage and aggregated dead zone models of longitudinal solute transport in streams

    Lees, Matthew J.; Camacho, Luis A.; Chapra, Steven


    The relationship between the distributed transient storage (TS) and lumped aggregate dead zone (ADZ) models of longitudinal solute transport in rivers and streams is examined by a parallel application to tracer data and through an investigation of parameter relationships. Both models accurately describe observed solute transport in a stream where the effects of storage or dead zones significantly affect longitudinal dispersion. A moment matching technique, based on theoretical temporal moments, is used to develop parameter relationships. Tests using the previously calibrated parameters, in addition to simulation experiments, show that the moment matching procedure allows ADZ model parameters to be reliably derived from TS model parameters and vice versa. An investigation of these parameter relationships reveals an important difference between the effective solute transport velocity and the average reach flow velocity in streams subject to transient storage or dead zone processes. A number of practical uses for the derived relationships are suggested, including the ability to utilize powerful methods of system identification in the estimation of TS model parameters.

  14. Individualized solutions to environmental problems: a case of automobile pollution

    Urmetzer, P.; Blake, D. E.; Guppy, N. [British Columbia Univ., Vancouver, BC (Canada)


    Air pollution associated with motor vehicle use is one of the prime indicators of the tension between consumerism and the environment. The use of private automobiles seems so convenient, whereas the alternatives are off-putting enough to make significant changes in personal transportation behaviour well-nigh impossible. At the same time, combating the air pollution associated with extensive use of cars has become one of the major policy objectives for cities around the world. Available policy alternatives can be divided into two categories: (1) incentives, such as improved public transportation, and (2) disincentives, such as environmental tax on gasoline. This paper attempt to directly assess links between these two alternatives, associated attitudes towards them, the level of public support for command and control (i.e. regulatory) policy approaches as well as for economic incentive/disincentive policies. Answers are sought and findings discussed relative to the link between opinions about the environment and support for different types of environmental policies, the usefulness of a rational choice perspective in explaining support for environmental policy alternatives, the role that partisan political attachments play in support of environmental policy approaches, and the roles played by environmental activism, knowledge, and action in shaping support for environmental policy alternatives. Overall results indicate that while most people living in urban environments support the ideas of environmental protection and would be willing to incur costs to confront the problem, exposure to air pollution plays an inconsequential (actually nearly non-existent) role in support of automobile-related environmental problems. Automobile users act like 'free-riders' i.e. they tend to support policies that socialize the cost of solutions rather than policies that attempt to pass the cost of pollution directly on to individual car owners. A sample of the responses to

  15. Milne, a routine for the numerical solution of Milne's problem

    Rawat, Ajay; Mohankumar, N.


    The routine Milne provides accurate numerical values for the classical Milne's problem of neutron transport for the planar one speed and isotropic scattering case. The solution is based on the Case eigen-function formalism. The relevant X functions are evaluated accurately by the Double Exponential quadrature. The calculated quantities are the extrapolation distance and the scalar and the angular fluxes. Also, the H function needed in astrophysical calculations is evaluated as a byproduct. Program summaryProgram title: Milne Catalogue identifier: AEGS_v1_0 Program summary URL: Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, No. of lines in distributed program, including test data, etc.: 701 No. of bytes in distributed program, including test data, etc.: 6845 Distribution format: tar.gz Programming language: Fortran 77 Computer: PC under Linux or Windows Operating system: Ubuntu 8.04 (Kernel version 2.6.24-16-generic), Windows-XP Classification: 4.11, 21.1, 21.2 Nature of problem: The X functions are integral expressions. The convergence of these regular and Cauchy Principal Value integrals are impaired by the singularities of the integrand in the complex plane. The DE quadrature scheme tackles these singularities in a robust manner compared to the standard Gauss quadrature. Running time: The test included in the distribution takes a few seconds to run.

  16. Near Earth Objects and Cascading Effects from the Policy Perspective: Implications from Problem and Solution Definition

    Lindquist, Eric


    The characterization of near-Earth-objects (NEOs) in regard to physical attributes and potential risk and impact factors presents a complex and complicates scientific and engineering challenge. The societal and policy risks and impacts are no less complex, yet are rarely considered in the same context as material properties or related factors. Further, NEO impacts are typically considered as discrete events, not as initial events in a dynamic cascading system. The objective of this contribution is to position the characterization of NEOs within the public policy process domain as a means to reflect on the science-policy nexus in regard to risks and multi-hazard impacts associated with these hazards. This will be accomplished through, first, a brief overview of the science-policy nexus, followed by a discussion of policy process frameworks, such as agenda setting and the multiple streams model, focusing events, and punctuated equilibrium, and their application and appropriateness to the problem of NEOs. How, too, for example, does NEO hazard and risk compare with other low probability, high risk, hazards in regard to public policy? Finally, we will reflect on the implications of alternative NEO "solutions" and the characterization of the NEO "problem," and the political and public acceptance of policy alternatives as a way to link NEO science and policy in the context of the overall NH9.12 panel.

  17. Characterization of NEOs from the Policy Perspective: Implications from Problem and Solution Definitions

    Lindquist, E.


    The characterization of near-Earth-objects (NEOs) in regard to physical attributes and potential risk and impact factors presents a complex and complicates scientific and engineering challenge. The societal and policy risks and impacts are no less complex, yet are rarely considered in the same context as material properties or related factors. The objective of this contribution is to position the characterization of NEOs within the public policy process domain as a means to reflect on the science-policy nexus in regard to risks associated with NEOs. This will be accomplished through, first, a brief overview of the science-policy nexus, followed by a discussion of several policy process frameworks, such as agenda setting and the multiple streams model, focusing events, and punctuated equilibrium, and their application and appropriateness to the problem of NEOs. How, too, for example, does NEO hazard and risk compare with other low probability, high risk, hazards in regard to public policy? Finally, we will reflect on the implications of alternative NEO "solutions" and the characterization of the NEO "problem," and the political and public acceptance of policy alternatives as a way to link NEO science and policy in the context of the overall NH004 panel.

  18. A Non-anthropic Solution to the Cosmological Constant Problem

    Spivey R. J.


    Full Text Available Accelerating cosmological expansion is driven by a minuscule vacuum energy density possibly seeking opportunities to decay to a true ground state. Quasar characteristics imply their central engines possess an intrinsic magnetic field compatible with the pres- ence of an electrically charged toroidal dark hole, an eternally collapsing structure lack- ing an event horizon. The possibility is consistent with the inability of black holes to capture particles in a universe of finite age, Einstein’s dismissal of the Schwarzschild metric as unphysical and the implausibility of the various paradoxes invoked by black hole existence. The uncloaked innards of these dark holes would expose immense vac- uum accelerations at their cores, inevitably tempered by Planck scale physics. The Unruh effect predicts that intense yet highly localised heating should occur there. As thermal energy gradually amasses and dissipates, radiation would eventually start to escape into the surrounding environment. Virtual from the d ark hole perspective, the emissions could not decrease the dark hole’s mass: the energy source must instead be the universal vacuum, the likely repository of dark energy. In analogy with core- collapse supernovae, neutrinos should dominate the cooling flows. Red-shifting to low energies upon escape, quantum degenerate haloes should for m predominantly around the largest galaxies. This mechanism is promising from the perspective of enabling the future universe to efficiently sustain aquatic life before stars become scarce, offering a biological yet decidedly non-anthropic solution to the cosmological constant problem.

  19. The Haplotyping Problem: An Overview of Computational Models and Solutions

    Paola Bonizzoni; Gianluca Della Vedova; Riccardo Dondi; Jing Li


    The investigation of genetic differences among humans has given evidence that mutations in DNA sequences are responsible for some genetic diseases. The most common mutation is the one that involves only a single nucleotide of the DNA sequence, which is called a single nucleotide polymorphism (SNP). As a consequence, computing a complete map of all SNPs occurring in the human populations is one of the primary goals of recent studies in human genomics. The construction of such a map requires to determine the DNA sequences that from all chromosomes. In diploid organisms like humans, each chromosome consists of two sequences called haplotypes. Distinguishing the information contained in both haplotypes when analyzing chromosome sequences poses several new computational issues which collectively form a new emerging topic of Computational Biology known as Haplotyping.This paper is a comprehensive study of some new combinatorial approaches proposed in this research area and it mainly focuses on the formulations and algorithmic solutions of some basic biological problems. Three statistical approaches are briefly discussed at the end of the paper.

  20. Solution to the ghost problem in fourth order derivative theories

    Mannheim, P D


    We present a solution to the ghost problem in fourth order derivative theories. In particular we study the Pais-Uhlenbeck fourth order oscillator model, a model which serves as a prototype for theories which are based on second plus fourth order derivative actions. Via a Dirac constraint method quantization we construct the appropriate quantum-mechanical Hamiltonian and Hilbert space for the system. We find that while the second-quantized Fock space of the general Pais-Uhlenbeck model does indeed contain the negative norm energy eigenstates which are characteristic of higher derivative theories, in the limit in which we switch off the second order action, such ghost states are found to move off shell, with the spectrum of asymptotic in and out S-matrix states of the pure fourth order theory which results being found to be completely devoid of states with either negative energy or negative norm. We provide additional insight into the structure of the Pais-Uhlenbeck theory by quantizing it via path integration ...

  1. Researching and Working for Transgender Youth: Contexts, Problems and Solutions

    Tiffany Jones


    Full Text Available In May 2016, two events epitomized the complexities of working for global transgender youth rights. First, United Nations Educational Scientific and Cultural Organisation (UNESCO hosted a ministerial event in which education ministers from around the world released a call to action for protection of students on the basis of their gender identity and expression in schools. Second, the United Nations (UN hosted an event celebrating the family, attended by conservative ministers and activists who mobilized family protectionist discourse against transgender students. This article contemplates, in light of transgender activist Raewyn Connell’s Southern Theory contributions, the complexity of global research and work for transgender youth. It considers key informant interviews with 50 stakeholders in the global push for transgender student rights in education, including members of government and non-government organisations, and academics from Northern and Southern countries. Problems in aiding transgender youth at the global level included safety concerns, the impacts of conservative advocates and media backlash (within family and national protectionist discourses, cultural complexities hampering engagement and translation, dissemination hindrances pertaining to established publishing biases, and financial and collaboration barriers. Solutions including virtual work; multi-level leadership; alliance-building; representation; visibility of transgender youth citizenship and family membership; and legal, financial and capacity-building aid are considered.

  2. Existence and Stability of Solutions for Implicit Multivalued Vector Equilibrium Problems

    Li Qiuying


    Full Text Available A class of implicit multivalued vector equilibrium problems is studied. By using the generalized Fan-Browder fixed point theorem, some existence results of solutions for the implicit multivalued vector equilibrium problems are obtained under some suitable assumptions. Moreover, a stability result of solutions for the implicit multivalued vector equilibrium problems is derived. These results extend and unify some recent results for implicit vector equilibrium problems, multivalued vector variational inequality problems, and vector variational inequality problems.


    李开泰; 黄艾香


    In this paper,we proposal stream surface and stream layer. By using classical tensor calculus, we derive 3-D Navier-Stokes Equations(NSE) in the stream layer under semigeodesic coordinate system, Navier-Stokes equation on the stream surface and 2-D Navier-Stokes equations on a two dimensional manifold. After introducing stream function on the stream surface, a nonlinear initial-boundary value problem satisfies by stream function is obtained, existence and uniqueness of its solution are proven. Based this theory we proposal a new method called "dimension split method" to solve 3D NSE.

  4. Optimization of explicit time-stepping algorithms and Stream-Function-Coordinate (SFC) concept for fluid dynamics problems

    Huang, Chung-Yuan

    A new formulation of the stream function based on a stream function coordinate (SFC) concept for inviscid flow field calculations is presented. In addition, a new method is developed not only to accelerate, but also to stabilize the iterative schemes for steady and unsteady, linear and non-linear, scalar and system of coupled, partial differential equations. With this theory, the limitation on the time step size of an explicit scheme for solving unsteady problems and the limitation on the relaxation factors of an iterative scheme for solving steady state problems could be analytically determined. Moreover, this theory allows the determination of the optimal time steps for explicit time-stepping schemes and the optimal values of the acceleration factors for iterative schemes, if the transient behavior is immaterial.

  5. Leak testing of cryogenic components - problems and solutions

    Srivastava, S P; Pandarkar, S P; Unni, T G; Sinha, A K; Mahajan, K; Suthar, R L [Centre for Design and Manufacture, Bhabha Atomic Research Centre, Mumbai 400085 (India)], E-mail:


    the vicinity of the moderator pot was driving the MSLD out of range. Since it was very difficult to locate the leak by Tracer Probe Method, some other technique was ventured to solve the problem of leak location. Finally, it was possible to locate the leak by observing the change in Helium background reading of MSLD during masking/unmasking of the welded joints. This paper, in general describes the design and leak testing aspects of cryogenic components of Cold Neutron Source and in particular, the problems and solutions for leak testing of transfer lines and moderator pot.

  6. Leak testing of cryogenic components — problems and solutions

    Srivastava, S. P.; Pandarkar, S. P.; Unni, T. G.; Sinha, A. K.; Mahajan, K.; Suthar, R. L.


    moderator pot was driving the MSLD out of range. Since it was very difficult to locate the leak by Tracer Probe Method, some other technique was ventured to solve the problem of leak location. Finally, it was possible to locate the leak by observing the change in Helium background reading of MSLD during masking/unmasking of the welded joints. This paper, in general describes the design and leak testing aspects of cryogenic components of Cold Neutron Source and in particular, the problems and solutions for leak testing of transfer lines and moderator pot.

  7. A streaming-based solution for remote visualization of 3D graphics on mobile devices.

    Lamberti, Fabrizio; Sanna, Andrea


    Mobile devices such as Personal Digital Assistants, Tablet PCs, and cellular phones have greatly enhanced user capability to connect to remote resources. Although a large set of applications are now available bridging the gap between desktop and mobile devices, visualization of complex 3D models is still a task hard to accomplish without specialized hardware. This paper proposes a system where a cluster of PCs, equipped with accelerated graphics cards managed by the Chromium software, is able to handle remote visualization sessions based on MPEG video streaming involving complex 3D models. The proposed framework allows mobile devices such as smart phones, Personal Digital Assistants (PDAs), and Tablet PCs to visualize objects consisting of millions of textured polygons and voxels at a frame rate of 30 fps or more depending on hardware resources at the server side and on multimedia capabilities at the client side. The server is able to concurrently manage multiple clients computing a video stream for each one; resolution and quality of each stream is tailored according to screen resolution and bandwidth of the client. The paper investigates in depth issues related to latency time, bit rate and quality of the generated stream, screen resolutions, as well as frames per second displayed.

  8. Learning Analytics Platform, towards an Open Scalable Streaming Solution for Education

    Lewkow, Nicholas; Zimmerman, Neil; Riedesel, Mark; Essa, Alfred


    Next generation digital learning environments require delivering "just-in-time feedback" to learners and those who support them. Unlike traditional business intelligence environments, streaming data requires resilient infrastructure that can move data at scale from heterogeneous data sources, process the data quickly for use across…

  9. Solid phase based DNA solution of the coloring problem

    PAN Linqiang; LIU Guangwu; XU Jin; LIU Yachun


    DNA computing has the potential to tackle computationally difficult problems that have real-world implications.The parallel search capabilities of DNA make it a valuable tool for approaching intractable computational problems,for which conventional computers have limited potentials.Up to now,many accomplishments have been achieved to improve its performance and increase its reliability.In this paper,the coloring problem has been solved by means of molecular biology techniques.The coloring problem is a well-known NP-complete problem.This work represents further evidence for the ability of DNA computing to solve NP-complete problems.

  10. The Approximate Solution of Some Plane Boundary Value Problems of the Moment Theory of Elasticity

    Roman Janjgava


    Full Text Available We consider a two-dimensional system of differential equations of the moment theory of elasticity. The general solution of this system is represented by two arbitrary harmonic functions and solution of the Helmholtz equation. Based on the general solution, an algorithm of constructing approximate solutions of boundary value problems is developed. Using the proposed method, the approximate solutions of some problems on stress concentration on the contours of holes are constructed. The values of stress concentration coefficients obtained in the case of moment elasticity and for the classical elastic medium are compared. In the final part of the paper, we construct the approximate solution of a nonlocal problem whose exact solution is already known and compare our approximate solution with the exact one. Supposedly, the proposed method makes it possible to construct approximate solutions of quite a wide class of boundary value problems.

  11. Existence of solutions for quasistatic problems of unilateral contact with nonlocal friction for nonlinear elastic materials

    Alain Mignot


    Full Text Available This paper shows the existence of a solution of the quasi-static unilateral contact problem with nonlocal friction law for nonlinear elastic materials. We set up a variational incremental problem which admits a solution, when the friction coefficient is small enough, and then by passing to the limit with respect to time we obtain a solution.


    Cheng-xian Xu; Xiao-liang He; Feng-min Xu


    An effective continuous algorithm is proposed to find approximate solutions of NP-hard max-cut problems. The algorithm relaxes the max-cut problem into a continuous nonlinear programming problem by replacing n discrete constraints in the original problem with one single continuous constraint. A feasible direction method is designed to solve the resulting nonlinear programming problem. The method employs only the gradient evaluations of the objective function, and no any matrix calculations and no line searches are required.This greatly reduces the calculation cost of the method, and is suitable for the solution of large size max-cut problems. The convergence properties of the proposed method to KKT points of the nonlinear programming are analyzed. If the solution obtained by the proposed method is a global solution of the nonlinear programming problem, the solution will provide an upper bound on the max-cut value. Then an approximate solution to the max-cut problem is generated from the solution of the nonlinear programming and provides a lower bound on the max-cut value. Numerical experiments and comparisons on some max-cut test problems (small and large size) show that the proposed algorithm is efficient to get the exact solutions for all small test problems and well satisfied solutions for most of the large size test problems with less calculation costs.

  13. A Case Base for Requirements Engineering: Problem Categories and Solution Techniques

    Sikkel, Klaas; Wieringa, Roel; Engmann, Rolf


    We introduce a notion of business problem frames, categorizing the type of IT requirements problems found in organizations, as opposed to Jackson’s problem frames which describe a problem in terms of the solution to that problem. A survey of students’ projects showed that this a viable notion. We in

  14. Parents’ Aggressive Influences and Children's Aggressive Problem Solutions with Peers

    Duman, Sarah; Margolin, Gayla


    This study examined children's aggressive and assertive solutions to hypothetical peer scenarios in relation to parents’ responses to similar hypothetical social scenarios and parents’ actual marital aggression. The study included 118 9−10 year old children, and their mothers and fathers. Children's aggressive solutions correlated with same-sex parents’ actual marital aggression. For children with mothers who exhibit low actual marital aggression, mothers’ aggressive solutions to hypothetical...



    In this paper,authors discuss the numerical methods of general discontinuous boundary value problems for elliptic complex equations of first order.They first give the well posedness of general discontinuous boundary value problems,reduce the discontinuousboundary value problems to a variation problem,and then find the numerical solutions ofabove problem by the finite element method.Finally authors give some error-estimates of the foregoing numerical solutions.

  16. A bilinear programming solution to the quadratic assignment problem

    J.F. Kaashoek (Johan); J.H.P. Paelinck (Jean)


    textabstractThe quadratic assignment problem (QAP) or maximum acyclical graph problem is well documented (see e.g. Pardalos and Wolkowicz, 1994). One of the authors has published some material, in which it was tried, by structuring the problem additionally, to bring it as closely as possible in the

  17. 100 great problems of elementary mathematics their history and solution

    Dorrie, Heinrich


    Problems that beset Archimedes, Newton, Euler, Cauchy, Gauss, Monge and other greats, ready to challenge today's would-be problem solvers. Among them: How is a sundial constructed? How can you calculate the logarithm of a given number without the use of logarithm table? No advanced math is required. Includes 100 problems with proofs.

  18. Towards faster solution of large power flow problems

    Idema, R.; Papaefthymiou, G.; Lahaye, D.J.P.; Vuik, C.; Van der Sluis, L.


    Current and future developments in the power system industry demand fast power flow solvers for larger power flow problems. The established methods are no longer viable for such problems, as they are not scalable in the problem size. In this paper, the use of Newton-Krylov power flow methods is prop

  19. Using Diagrams as Tools for the Solution of Non-Routine Mathematical Problems

    Pantziara, Marilena; Gagatsis, Athanasios; Elia, Iliada


    The Mathematics education community has long recognized the importance of diagrams in the solution of mathematical problems. Particularly, it is stated that diagrams facilitate the solution of mathematical problems because they represent problems' structure and information (Novick & Hurley, 2001; Diezmann, 2005). Novick and Hurley were the first…

  20. Calculation Error of Numerical Solution for a Boundary—Value Inverse Heat Conduction Problem

    LiXijing; HeQun; 等


    A one-dimensional linear inverse heat conduction problem is studied in this paper,This ill-posed problem is replaced by the perturbed problem with a non-localized boundary condition.After the derivation of its closed-from analytical solution,the calculation error can be determinde by the comparison between the numerical and exact solutions.

  1. Using Diagrams as Tools for the Solution of Non-Routine Mathematical Problems

    Pantziara, Marilena; Gagatsis, Athanasios; Elia, Iliada


    The Mathematics education community has long recognized the importance of diagrams in the solution of mathematical problems. Particularly, it is stated that diagrams facilitate the solution of mathematical problems because they represent problems' structure and information (Novick & Hurley, 2001; Diezmann, 2005). Novick and Hurley were the first…

  2. Exact solutions to some axisymmetric problems in magnetohydrodynamics

    Sheriazdanov, G.B.


    Steady-state axisymmetric flow of an incompressible perfectly conducting fluid is analyzed with allowance for the circular motion and the azimuthal component of the magnetic field. In the case of a nonviscous fluid, an equation of motion integral is obtained which relates the Bernoulli function to the azimuthal component of the velocity and magnetic fields. For the case of the rotation of a viscous fluid as a solid, the Bernoulli integral depends on the stream function, Reynolds and Alfven numbers, and the twisting parameter. 5 references.

  3. Morrey Regularity of the Solution to the Dirichlet Problem


    @@To study the local regularity of solutions to second orderelliptic partial differential equations, Morrey in [1] introduced somefunction spaces, which are called the Morrey spaces today. Since then, manymathematicians have studied regularities of solutions to some kinds of secondorder elliptic equations in Morrey spaces.

  4. Positive Solutions of Singular Boundary Value Problem of Negative Exponent Emden–Fowler Equation

    Yuxia Wang; Xiyu Liu


    This paper investigates the existence of positive solutions of a singular boundary value problem with negative exponent similar to standard Emden–Fowler equation. A necessary and sufficient condition for the existence of [0, 1] positive solutions as well as 1[0, 1] positive solutions is given by means of the method of lower and upper solutions with the Schauder fixed point theorem.

  5. Multichannel Coherent Lightwave Systems: Practical Problems and Possible Solutions

    Tanrikulu, Mustafa Okan


    An extensive field deployment of optical fiber has already undergone, and it is expected to replace the copper within the next twenty years. The ultimate goal in communications and computing industry is to make all optical networks possible in the near future. In this context, certain important practical problems that exist in multichannel coherent lightwave systems are studied, and possible solutions are provided in this dissertation. It is shown that the capacity of dual-filter FSK heterodyne lightwave systems can be enhanced by exploiting the interrelationship between the frequency separation and the amount of laser phase noise. Optimum choice of intermediate frequency filter bandwidth also improves the system capacity. The effect of finite intermediate frequency on the performance of ASK heterodyne lightwave systems is also studied. The results obtained show that certain finite choices of intermediate frequency allows ideal envelope detection. Thus, one can design a multichannel ASK heterodyne lightwave system with relatively small optical domain channel spacings as long as optimum values of intermediate frequency is used. Otherwise, either the channel spacings should be increased, which, in turn, reduces the system capacity, or an extra sensitivity penalty should be tolerated which translates into an increase in the system cost. It is also shown that the effect of finite intermediate frequency is more significant in negligible linewidth systems. On the other hand, non-negligible linewidth systems are more immune to the effects of finite intermediate frequency. However, the amount of channel spacing in a multichannel system significantly increases in the case of non-negligible linewidth systems due to spectral broadening of information bearing signal. The effect of crosstalk in multi-channel ASK heterodyne lightwave systems with polarization control is also studied, and the results obtained show that choice of intermediate frequency filter bandwidth, in



    We apply a fixed point theorem to verify the existence of at least three positive solutions to a multi-point boundary value problem with p-Laplacian. Existence criteria which ensure the existence of triple positive solutions are established.

  7. On optimal solutions of the constrained ℓ 0 regularization and its penalty problem

    Zhang, Na; Li, Qia


    The constrained {{\\ell}0} regularization plays an important role in sparse reconstruction. A widely used approach for solving this problem is the penalty method, of which the least square penalty problem is a special case. However, the connections between global minimizers of the constrained {{\\ell}0} problem and its penalty problem have never been studied in a systematic way. This work provides a comprehensive investigation on optimal solutions of these two problems and their connections. We give detailed descriptions of optimal solutions of the two problems, including existence, stability with respect to the parameter, cardinality and strictness. In particular, we find that the optimal solution set of the penalty problem is piecewise constant with respect to the penalty parameter. Then we analyze in-depth the relationship between optimal solutions of the two problems. It is shown that, in the noisy case the least square penalty problem probably has no common optimal solutions with the constrained {{\\ell}0} problem for any penalty parameter. Under a mild condition on the penalty function, we establish that the penalty problem has the same optimal solution set as the constrained {{\\ell}0} problem when the penalty parameter is sufficiently large. Based on the conditions, we further propose exact penalty problems for the constrained {{\\ell}0} problem. Finally, we present a numerical example to illustrate our main theoretical results.

  8. The Lunar Internal Structure Model: Problems and Solutions

    Nefedyev, Yuri; Gusev, Alexander; Petrova, Natalia; Varaksina, Natalia

    decomposition of gravitational field of the Moon of members up to 165th order with a high degree of accuracy. Judging from the given data, the distinctive feature of the Moon’s gravitational field is that harmonics of the third and even the fourth order are comparable with harmonics of the second order, except for member J2. General conclusion: according to recent data, the true figure of the Moon is much more complex than a three-axis ellipsoid. Gravitational field and dynamic figure of the multilayered Moon: One of the main goals of selenodesy is the study of a dynamic figure of the Moon which determines distribution of the mass within the Moon’s body. A dynamic figure is shaped by the inertia ellipsoid set by values of resultant moments of inertia of the Moon A, B, C and their orientation in space. Selenoid satellites (SS) open new and most perspective opportunities in the study of gravitational field and the Moon’s figure. SSs “Moon 10”, “Apollo”, “Clementine”, “Lunar Prospector” trajectory tracking data processing has allowed for identification of coefficients in decomposition of gravitational field of the Moon of members up to 165th order with a high degree of accuracy. Judging from the given data, the distinctive feature of the Moon’s gravitational field is that harmonics of the third and even the fourth order are comparable with harmonics of the second order. Difference from zero of c-coefficients proves asymmetry of gravitational fields on the visible and invisible sides of the Moon. As a first attempt at solving the problem, the report presents the survey of internal structure of the Moon, tabulated values of geophysical parameters and geophysical profile of the Moon, including liquid lunar core, analytical solution of Clairaut’s equation for the two-layer model of the Moon; mathematical and bifurcational analysis of solution based on physically justified task options; original debugged software in VBA programming language for computer



    In this paper,we study the existence of solutions to a third-order three-point boundary value problem.By imposing certain restrictions on the nonlinear term,we prove the existence of at least one solution to the boundary value problem by the method of lower and upper solutions.We are interested in the construction of lower and upper solutions.

  10. Fourth-Order Four-Point Boundary Value Problem: A Solutions Funnel Approach

    Panos K. Palamides


    Full Text Available We investigate the existence of positive or a negative solution of several classes of four-point boundary-value problems for fourth-order ordinary differential equations. Although these problems do not always admit a (positive Green's function, the obtained solution is still of definite sign. Furthermore, we prove the existence of an entire continuum of solutions. Our technique relies on the continuum property (connectedness and compactness of the solutions funnel (Kneser's Theorem, combined with the corresponding vector field.

  11. Uniformly valid solutions of the coupling turning-point problem in revolution shell vibration


    The turning-point problem in free vibration of revolution shells has the coupling property between the bending and membrane solutions. The uniformly valid solutions for this coupling turning-point problem are obtained based on three categories of generalized functions. Furthermore, they are verified to be uniformly valid in the low, turning-point and high frequency ranges. The obtained solutions exhibit a symmetric coupling structure between the bending and membrane solutions.

  12. Two Dynamic Discrete Choice Estimation Problems and Simulation Method Solutions

    Steven Stern


    This paper considers two problems that frequently arise in dynamic discrete choice problems but have not received much attention with regard to simulation methods. The first problem is how to simulate unbiased simulators of probabilities conditional on past history. The second is simulating a discrete transition probability model when the underlying dependent variable is really continuous. Both methods work well relative to reasonable alternatives in the application discussed. However, in bot...

  13. A Solution Methodology for the Variable-Level Scheduling Problem


    distribution unlimited 13. ABSTRACT (Maxtmum 200 words) This study looked at a specific scheduling problem for a Department of Defense agency. A heuristic algorithm was...the DoD problem in this research. Bala Shetty’s article, " A Heuristic Algorithm for a Network Problem with Variable Upper Bounds", also uses a...could be used, but this would undoubtably have long comrt ational times. The research, then, involving a heuristic algorithm to generate an effective

  14. Java EE 7 recipes a problem-solution approach

    Juneau, Josh


    Java EE 7 Recipes takes an example-based approach in showing how to program Enterprise Java applications in many different scenarios. Be it a small-business web application, or an enterprise database application, Java EE 7 Recipes provides effective and proven solutions to accomplish just about any task that you may encounter. You can feel confident using the reliable solutions that are demonstrated in this book in your personal or corporate environment. The solutions in Java EE 7 Recipes are built using the most current Java Enterprise specifications, including EJB 3.2, JSF 2.2, Expression La

  15. On the solution of a pairing problem in the continuum

    Mercenne, A; Dukelsky, J; Płoszajczak, M


    We present a generalized Richardson solution for fermions interacting with the pairing interaction in both discrete and continuum parts of the single particle (s.p.) spectrum. The pairing Hamiltonian is based on the rational Gaudin (RG) model which is formulated in the Berggren ensemble. We show that solutions of the generalized Richardson equations are exact in the two limiting situations: (i) in the pole approximation and (ii) in the s.p. continuum. If the s.p. spectrum contains both discrete and continuum parts, then the generalized Richardson equations provide accurate solutions for the Gamow Shell Model.

  16. Optimal Component Lumping: problem formulation and solution techniques

    Lin, Bao; Leibovici, Claude F.; Jørgensen, Sten Bay


    to determine the lumping scheme. Given an objective function defined with a linear weighting rule, an optimal lumping problem is formulated as a mixed integer nonlinear programming (MINLP) problem both in discrete and in continuous settings. A reformulation of the original problem is also presented, which...... significantly reduces the number of independent variables. The application to a system with 144 components demonstrates that the optimal lumping problem can be efficiently solved with a stochastic optimization method, Tabu Search (TS) algorithm. The case study also reveals that the discrete formulation...

  17. Digital dice computational solutions to practical probability problems

    Nahin, Paul J


    Some probability problems are so difficult that they stump the smartest mathematicians. But even the hardest of these problems can often be solved with a computer and a Monte Carlo simulation, in which a random-number generator simulates a physical process, such as a million rolls of a pair of dice. This is what Digital Dice is all about: how to get numerical answers to difficult probability problems without having to solve complicated mathematical equations. Popular-math writer Paul Nahin challenges readers to solve twenty-one difficult but fun problems, from determining the

  18. The Seeking Solutions Approach: Solving Challenging Business Problems with Local Open Innovation

    Christophe Deutsch


    Full Text Available How can small and medium-sized enterprises try open innovation and increase their level of collaboration with local partners? This article describes a possible solution: the Seeking Solutions approach. The Seeking Solutions process consists of four steps: a call for problems, problem selection, problem broadcast, and a collaborative event. This approach has been successfully used for the Quebec Seeks Solutions events in 2010 and 2012 with concrete results and real impacts. By mixing open innovation and collaboration, the Seeking Solutions approach has introduced a new concept: local open innovation.

  19. A new branch of mountain pass solutions for the choreographical 3-body problem

    Arioli, G; Terracini, S


    We prove the existence of a new branch of solutions of Mountain Pass type for the periodic 3-body problem with choreographical constraint. At first we describe the variational structure of the action functional associated to the choreographical three body problem in R^3. In the second part, using on a bisection algorithm, we provide a numerical non-rigorous solution of Mountain Pass type for this problem in a rotating frame with angular velocity 1.5. The last step consists in the rigorous computer-assisted proof of the existence of a full branch of solutions for the problem starting from the Mountain Pass solution detected numerically.

  20. Parallel implementation of domain decomposition methods for the solution of elliptic boundary-value problems

    Gazzaniga, G.; Sacchi, G. [Istituto di Analisi Numerica, Pavia (Italy)


    Different Domain Decomposition techniques for the solution of elliptic boundary-value problems are considered. The results of the implementation on a parallel distributed memory architecture are discussed.


    吕念春; 程靳; 程云虹; 屈德志


    By the theory of complex functions, a penny-shaped crack on axially symmetric propagating problems for composite materials was studied. The general representations of the analytical solutions with arbitrary index of self-similarity were presented for fracture elastodynamics problems on axially symmetry by the ways of self-similarity under the /addershaped loads. The problerns dealt with can be transformed into Riemann-Hilbert problems and their closed analytical solutions are obtained rather simple by this method. After those analytical solutions are utilized by using the method of rotational superposition theorem in conjunction with that of Smirnov-Sobolev, the solutions of arbitrary complicated problems can be obtained.

  2. Limit theorems for solutions of stochastic differential equation problems

    J. Vom Scheidt


    Full Text Available In this paper linear differential equations with random processes as coefficients and as inhomogeneous term are regarded. Limit theorems are proved for the solutions of these equations if the random processes are weakly correlated processes.

  3. A Priori Estimates for Solutions of Boundary Value Problems for Fractional-Order Equations

    Alikhanov, A A


    We consider boundary value problems of the first and third kind for the diffusionwave equation. By using the method of energy inequalities, we find a priori estimates for the solutions of these boundary value problems.



    A class of Robin boundary value problem for reaction diffusion equation is considered. Under suitable conditions, using the theory of differential inequalities the existence and asymptotic behavior of the corner layer solution to the initial boundary value problem are studied.


    LiHongyu; SunJingxian


    By using topological method, we study a class of boundary value problem for a system of nonlinear ordinary differential equations. Under suitable conditions,we prove the existence of positive solution of the problem.

  6. Solutions to two problems of G.J.Wang


    The problem as to whether the sub-T0 separation and complete regularity are invariant under homeomorphism is answered negatively.And,the problem of multiplicativity of the complete regularity in general L-fuzzy topological spaces is also answered negatively.

  7. Solutions of inverse problems for biodegradation of xenobiotic polymers

    Watanabe, Masaji; Kawai, Fusako


    Mathematical techniques are applied to a microbial depolymerization process. A mathematical model for the transition of the weight distribution and the microbial population is described. Inverse problems for a molecular factor and a time factor of a degradation rate are derived. Numerical techniques to solve the inverse problems are illustrated, and numerical results are presented.

  8. Biological regeneration of ferric (Fe3+) solution during desulphurisation of gaseous streams: effect of nutrients and support material.

    Mulopo, Jean; Schaefer, L


    This paper evaluates the biological regeneration of ferric Fe3+ solution during desulphurisation of gaseous streams. Hydrogen sulphide (H2S) is absorbed into aqueous ferric sulphate solution and oxidised to elemental sulphur, while ferric ions Fe3+ are reduced to ferrous ions Fe2+. During the industrial regeneration of Fe3+, nutrients and trace minerals usually provided in a laboratory setup are not present and this depletion of nutrients may have a negative impact on the bacteria responsible for ferrous iron oxidation and may probably affect the oxidation rate. In this study, the effect of nutrients and trace minerals on ferrous iron oxidation have been investigated and the results showed that the presence of nutrients and trace minerals affects the efficiency of bacterial Fe2+oxidation. The scanning electron microscopy analysis of the geotextile support material was also conducted and the results showed that the iron precipitate deposits appear to play a direct role on the bacterial biofilm formation.

  9. A Discrete Optimization Description for the Solutions in the Matching Problem

    Walied H. Sharif


    Full Text Available This study was concerned with the characterization of solutions in the matching problem. The general mixed-integer programming problem is given together with the definition of the convex hull of the integer solutions. In addition, the matching problem is defined as an integer problem and an algorithm is described to find the optimum matchings. Some illustrative examples are introduced to clarify the presented theory in the study.

  10. Existence and non-uniqueness of similarity solutions of a boundary-layer problem

    Hussaini, M. Y.; Lakin, W. D.


    A Blasius boundary value problem with inhomogeneous lower boundary conditions f(0) = 0 and f'(0) = - lambda with lambda strictly positive was considered. The Crocco variable formulation of this problem has a key term which changes sign in the interval of interest. It is shown that solutions of the boundary value problem do not exist for values of lambda larger than a positive critical value lambda. The existence of solutions is proven for 0 lambda lambda by considering an equivalent initial value problem. It is found however that for 0 lambda lambda, solutions of the boundary value problem are nonunique. Physically, this nonuniqueness is related to multiple values of the skin friction.

  11. Existence and non-uniqueness of similarity solutions of a boundary layer problem

    Hussaini, M. Y.; Lakin, W. D.


    A Blasius boundary value problem with inhomogeneous lower boundary conditions f(0) = 0 and f'(0) = - lambda with lambda strictly positive was considered. The Crocco variable formulation of this problem has a key term which changes sign in the interval of interest. It is shown that solutions of the boundary value problem do not exist for values of lambda larger than a positive critical value lambda. The existence of solutions is proven for 0 lambda lambda by considering an equivalent initial value problem. It is found however that for 0 lambda lambda, solutions of the boundary value problem are nonunique. Physically, this nonuniqueness is related to multiple values of the skin friction.

  12. Computational solution of the defect stream-function equation for nonequilibrium turbulent boundary layers

    Barnwell, Richard W.


    The derivation of the accurate, second-order, almost linear, approximate equation governing the defect stream function for nonequilibrium compressible turbulent boundary layers is reviewed. The similarity of this equation to the heat conduction equation is exploited in the development of an unconditionally stable, tridiagonal computational method which is second-order accurate in the marching direction and fourth-order accurate in the surface-normal direction. Results compare well with experimental data. Nonlinear effects are shown to be small. This two-dimensional method is simple and has been implemented on a programmable calculator.

  13. An investigation of the accuracy of finite difference methods in the solution of linear elasticity problems

    Bauld, N. R., Jr.; Goree, J. G.


    The accuracy of the finite difference method in the solution of linear elasticity problems that involve either a stress discontinuity or a stress singularity is considered. Solutions to three elasticity problems are discussed in detail: a semi-infinite plane subjected to a uniform load over a portion of its boundary; a bimetallic plate under uniform tensile stress; and a long, midplane symmetric, fiber reinforced laminate subjected to uniform axial strain. Finite difference solutions to the three problems are compared with finite element solutions to corresponding problems. For the first problem a comparison with the exact solution is also made. The finite difference formulations for the three problems are based on second order finite difference formulas that provide for variable spacings in two perpendicular directions. Forward and backward difference formulas are used near boundaries where their use eliminates the need for fictitious grid points.

  14. Application of a Two-Storage Zone Model to Characterize Transport and Reaction of Solutes and Solute Tracers in Streams and Wetlands

    Harvey, J. W.; Newlin, J. T.


    Natural streams and wetlands exchange water and solutes between the main flow zone and a complex assemblage of "transient storage" zones that include stagnant water in pools, areas of flow recirculation, and subsurface flow paths through bed sediments and deeper alluvial sediments. Exchange between faster moving waters of the main flow zone and the slowly moving waters in storage zones results in delayed downstream transport of solutes, relative to what would be predicted from velocity measurements in the main flow zone. The transient storage concept is useful particularly for understanding the fate and transport of contaminants in streams, such as nutrients and metals, because solutes transported into storage zones come in close contact with reactive substrates such as sediment, periphyton, and macrophyte leaves. Delayed transport and characterization of transient storage zones can be quantified with solute tracer injections and modeling. Many of the widely used stream transport models that consider transient storage, such as the OTIS-P model (Runkel, USGS WRIR 98-4018, 1998), use only a single storage zone (i.e., linear reservoir with exponential residence time distribution) to account for transient storage. Choi et al. (WRR, 36:1511, 2000) showed that a model with two independent storage zones improved the characterization of transient storage in systems having both `slow' and `fast' exchange zones while retaining an appropriate level of model simplicity. We modified the OTIS-P model to include the option of simulating transport by allowing for exchange with two independent storage zones. The new model package, called OTIS-2Stor, also incorporates new options for weighting tracer concentration measurements while estimating the parameters of the model using the same non-linear least squares regression routine that is included in OTIS-P. Our experiences in headwater channels of Indiana and in the Florida Everglades demonstrate that, if used in conjunction with

  15. 200 more puzzling physics problems with hints and solutions

    Gnädig, Péter; Vigh, Máté


    Like its predecessor, 200 Puzzling Physics Problems, this book is aimed at strengthening students' grasp of the laws of physics by applying them to situations that are practical, and to problems that yield more easily to intuitive insight than to brute-force methods and complex mathematics. The problems are chosen almost exclusively from classical, non-quantum physics, but are no easier for that. They are intriguingly posed in accessible non-technical language, and require readers to select an appropriate analysis framework and decide which branches of physics are involved. The general level of sophistication needed is that of the exceptional school student, the good undergraduate, or the competent graduate student; some physics professors may find some of the more difficult questions challenging. By contrast, the mathematical demands are relatively minimal, and seldom go beyond elementary calculus. This further book of physics problems is not only instructive and challenging, but also enjoyable.

  16. Interpersonal problems and personality: using three factor solutions.

    McDonald, Michelle J; Linden, Paul D


    Attempting to bridge the gap between psychotherapy research on interpersonal discord and personality research on factors of normal and abnormal personality, the present study uses personality factors to predict interpersonal problems. Eysenck's P-E-N (Psychoticism-Extraversion-Neuroticism) model of personality and its correspondent index, the Eysenck Personality Questionnaire-Revised is used as a schema from which to conceptualize and measure personality. Horowitz's Inventory of Interpersonal Problems, which includes six problems commonly reported by psychotherapy patients at intake (hard to be assertive, hard to be submissive, hard to be intimate, hard to be sociable, too controlling, and too responsible), was used as an index of interpersonal distress. Hierarchical multiple regression, in which the most significant predictor was entered into the equation first, indicate significant prediction of various problems by the personality factors considered here. Results are discussed in the context of interpersonal theory.

  17. A new model for solution of complex distributed constrained problems

    Al-Maqtari, Sami; Babkin, Eduard


    In this paper we describe an original computational model for solving different types of Distributed Constraint Satisfaction Problems (DCSP). The proposed model is called Controller-Agents for Constraints Solving (CACS). This model is intended to be used which is an emerged field from the integration between two paradigms of different nature: Multi-Agent Systems (MAS) and the Constraint Satisfaction Problem paradigm (CSP) where all constraints are treated in central manner as a black-box. This model allows grouping constraints to form a subset that will be treated together as a local problem inside the controller. Using this model allows also handling non-binary constraints easily and directly so that no translating of constraints into binary ones is needed. This paper presents the implementation outlines of a prototype of DCSP solver, its usage methodology and overview of the CACS application for timetabling problems.

  18. Analytical mechanics solutions to problems in classical physics

    Merches, Ioan


    Fundamentals of Analytical Mechanics Constraints Classification Criteria for Constraints The Fundamental Dynamical Problem for a Constrained Particle System of Particles Subject to Constraints Lagrange Equations of the First KindElementary Displacements Generalities Real, Possible and Virtual Displacements Virtual Work and Connected Principles Principle of Virtual WorkPrinciple of Virtual Velocities Torricelli's Principle Principles of Analytical Mechanics D'alembert's Principle Configuration Space Generalized Forces Hamilton's Principle The Simple Pendulum Problem Classical (Newtonian) Formal

  19. Solution of Phase Compensation Problems for ISAR Imaging

    QIUXiaohui; ZHAOYang; HENGWangChengAlice


    Solution of phase compensation for Inverse synthetic aperture radar (ISAR) imaging has been analyzed in classification, including maximum likelihoodbased phase compensation and minimum entropy-based phase compensation. Further, it is proved in paper that minimum entropy method actually is not an optimal solution since its extreme small value is only a local extremum. Also comparison between two type methods has been done for real ISAR data processing together with discussion on characteristics of phase compensation for those methods in this paper. Results show that minimum entropy method has better focusing than maximum likelihood method, however, it is with huge computation work.


    Soyalp TAMÇELİK


    Full Text Available In this research, the methodological problems and irregularities in the studies that were made or are still made regarding the Cyprus problem were considered. However this information can not be understood unless put into a theoretical framework.Empirical histories read about the Cyprus problem, in truth, are not factual at all. Conversely, they are composed of a series of accepted judgments, which necessitates setting eyes on, interpreting and evaluating factual stacks of knowledge. However, as dealing with these stacks, researchers studying on the Cyprus problem are supposed to identify events and conditions correctly with time, location and person coordination. Because it requires to dealing with, scrutinize, process and evaluate empirical content of history, and also to reestablish or make sense of social, political, economical, intellectual, aesthetical, religious, moral values and institutions of different cultures and civilizations both created by human experience and formed within this experience. Therefore, as making analysis on the Cyprus problem, it is of great importance to decide on the most suitable method in defining facts, know analytical problems and produce analytical category information.Pursuant to this fact, the analysis consists of three main chapters. While, in the first chapter, some ideas were stated on the method to be conducted in studies to be made on the Cyprus matter; methods and proposals to be accomplished in studies to be made on this matter were spoken in the second chapter. In the final chapter, concepts and facts in studies to be made on the Cyprus matter were mentioned.

  1. A Solution to Hammer's X-ray Reconstruction Problem

    Gardner, Richard J.; Kiderlen, Markus


    We propose algorithms for reconstructing a planar convex body K from possibly noisy measurements of either its parallel X-rays taken in a fixed finite set of directions or its point X-rays taken at a fixed finite set of points, in known situations that guarantee a unique solution when the data is...

  2. A general solution to some plane problems of micropolar elasticity

    Warren, William E.; Byskov, Esben


    functions, the solution is obtained in terms of two analytic functions and a third function satisfying the modified homogeneous Helmholtz equation. Expressions for the two-dimensional components of displacement, stress, and couple stress, along with the resultant force on a contour, are presented.We observe...

  3. Psychological considerations of man in space: Problems & solutions

    Kass, J.; Kass, R.; Samaltedinov, I.

    With concrete plans for long duration flight taking form a new impetus is lent to preparing man for this hostile and unnatural environment. Cramped conditions, isolation from family and loved ones, work stress, fear, and incompatibility with fellow crew, are but a few of the problems suffered by astronauts and cosmonauts during their long missions in orbit about the earth. Although criteria for selection of crew is one aspect of attacking the problem, it has not solved it Notwithstanding good selection, team combination, and counselling before flight, problems have still occurred with unwanted consequences. Incompatibility of team members, far from being the exception, has been frequent. This has been detrímental both physiologically and psychologically for the individual as well as for the operational success and safety of the missions. Because problems will inevitably occur in future long duration missions, especially when they are of international and multi-cultural nature, the importance of dealing with them is underlined. This paper takes a different approach towards ameliorating these problems, namely that of psychological group training before a mission.

  4. The Parabolas of Artzt in the Solution of a Geometric Problem of Minimum Length

    Klaoudatos, Nikos


    The article describes the solution of a geometric problem and how this problem was formed. During the investigation process, I discovered that the inscribed parabola in a triangle, known as the parabola of Artzt, a mathematical subject developed almost 120 years ago, was the decisive idea which directed me towards the solution. Moreover, in the…



    In this paper,we study the existence and approximation of solution to boundary value problems for impulsive differential equations with delayed arguments.Sufficient conditions are established for the existence of a unique solution or extremal ones to the given problem.A monotone iterative technique is applied.



    The existence and multiplicity of positive solutions to a periodic boundary value problem for nonlinear third-order ordinary differential equation are established, based on the zero point theorem concerning cone expansion and compression of order type. Our main approach is different from the previous papers on the existence of multiple positive solutions to the similar problem.



    In this paper,we apply a fixed point theorem to verify the existence of multiple positive solutions to a p-Laplacian boundary value problem.Sufficient conditions are established which guarantee the existence of multiple positive solutions to the problem.



    In this paper, we are concerned with the existence and nonexistence of positive solutions to a three-point boundary value problems. By Krasnoselskii's fixed point theorem in Banach space, we obtain sufficient conditions for the existence and non-existence of positive solutions to the above three-point boundary value problems.

  9. Multiple Solutions to Problems in Mathematics Teaching: Do Teachers Really Value Them?

    Bingolbali, Erhan


    Solving problems in different ways is strongly advised for mathematics learning and teaching. There is, however, little data available on the examination of teachers' openness to and evaluation of different solutions to the problems. In this paper, the author examines classroom teachers' openness to different solutions (or to what extent they…

  10. Expanding the Space of Plausible Solutions in a Medical Tutoring System for Problem-Based Learning

    Kazi, Hameedullah; Haddawy, Peter; Suebnukarn, Siriwan


    In well-defined domains such as Physics, Mathematics, and Chemistry, solutions to a posed problem can objectively be classified as correct or incorrect. In ill-defined domains such as medicine, the classification of solutions to a patient problem as correct or incorrect is much more complex. Typical tutoring systems accept only a small set of…

  11. Expanding the Space of Plausible Solutions in a Medical Tutoring System for Problem-Based Learning

    Kazi, Hameedullah; Haddawy, Peter; Suebnukarn, Siriwan


    In well-defined domains such as Physics, Mathematics, and Chemistry, solutions to a posed problem can objectively be classified as correct or incorrect. In ill-defined domains such as medicine, the classification of solutions to a patient problem as correct or incorrect is much more complex. Typical tutoring systems accept only a small set of…

  12. Solutions to Cosmological Problems with Energy Conservation and Varying c, G and $\\Lambda$

    Gopakumar, P


    The flatness and cosmological constant problems are solved with varying speed of light c, gravitational coupling strength G and cosmological parameter Lambda, by explicitly assuming energy conservation of observed matter. The present solution to the flatness problem is the same as the previous solution in which energy conservation was absent.

  13. Comparison of Two Instructional Strategies for Teaching the Solution to Verbal Problems. Final Report.

    Bassler, Otto C.; And Others

    Two distinct strategies for teaching the solution to verbal problems were compared. Programs of instruction were prepared that reflected the Polya Method (read and understand the problem, plan for a solution, carry out the plan, and check the result) and the Dahmus Method (translate the verbal statements into mathematical symbols prior to solving…

  14. A simple solution to the Polonyi problem in gravity mediation

    Harigaya, Keisuke [Kavli IPMU, TODIAS, University of Tokyo, Kashiwa 277-8583 (Japan); Ibe, Masahiro [ICRR, University of Tokyo, Kashiwa 277-8582 (Japan); Kavli IPMU, TODIAS, University of Tokyo, Kashiwa 277-8583 (Japan); Schmitz, Kai, E-mail: [Kavli IPMU, TODIAS, University of Tokyo, Kashiwa 277-8583 (Japan); Yanagida, Tsutomu T. [Kavli IPMU, TODIAS, University of Tokyo, Kashiwa 277-8583 (Japan)


    The Polonyi field is a necessary ingredient in any viable scenario of gravity mediated supersymmetry breaking. However, it is known that the presence of the Polonyi field leads to several serious cosmological problems, which are collectively referred to as the Polonyi problem. We show that the Polonyi problem can be solved if the Polonyi field couples to a pseudo-modulus in the superpotential and this pseudo-modulus has a large field expectation value during inflation. To illustrate our idea, we construct an explicit model which can be readily connected to scenarios of gravity mediation. The generation of the mass parameters contained in our model by strong gauge dynamics is also commented on.

  15. A solution to Lov\\'asz's Seventeenth problem

    Hatami, Hamed


    Many fundamental theorems in extremal graph theory can be expressed as linear inequalities between homomorphism densities. In the language of quantum graphs the validity of a linear inequality between homomorphism densities is equivalent to the positivity of a corresponding quantum graph. Lov\\'asz composed a collection of open problems in this area, and in Problem 17 he asks whether every positive quantum graph can be represented as a sum of squares of labeled quantum graphs. A related question by Razborov asks whether every true linear inequality between homomorphism densities can be proven using certain applications of the Cauchy-Schwarz inequality. We answer both questions in the negative by introducing explicit valid inequalities that do not satisfy the required conditions. Razborov's question and Lov\\'asz's seventeenth problem are both precise instances of a general question of Razborov whether every true linear inequality between homomorphism densities can be proven using a finite amount of manipulation...

  16. Effect of PLISSIT Model on Solution of Sexual Problems

    Esra Uslu


    Full Text Available This systematic review study aims to determine the effect of PLISSIT model (permission, limited information, special suggestions, intensive therapy in the care of individuals having sexual problems. Two of the studies included in the systematic review have been carried out in Iran and one of them in Turkey. These studies were limited to the patients with stoma and women having sexual problems. Results presented that care via PLISSIT model improves the sexual functions and reduces sexual stress, increases the sexual desire, sexual arousal, lubrication, orgasm, sexual satisfaction and frequency of sexual activity. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(1: 52-63

  17. Multi-party arbitration in international trade: problems and solutions

    Siig, Kristina


    Legal disputes regarding international trade frequently involve more than two parties. This leads to problems, as the preferred means of dispute resolution within international trade - arbitration - tends to be ill-equipped to handle such disputes. The topic of the paper is arbitration as a means...... of dispute resolution in a multy-party set-up. Both the possible legal bases and the problems encountered are considere. It is concluded that arbitration is still the only real option to the parties in international business disputes and that many of the shortcomings  may be contered by skilful drafting...... of the arbitration agreement...

  18. On the Sz\\"usz's Solution to Gauss' Problem

    Lascu, Dan


    The present paper deals with Gauss' problem on continued fractions. We present a new proof of a theorem which Sz\\"usz applied in order to solve this problem. To be noted, that we obtain the value $0.7594...$ for $q$, which has been optimized by Sz\\"usz in his 1961 paper "\\"Uber einen Kusminschen Satz", where the value 0.485 is obtained for $q$. In our proof, we make use of an important property of the Perron-Frobenius operator of $\\tau$ under $\\gamma$, where $\\tau$ is the continued fraction transformation, and $\\gamma$ is the Gauss' measure.

  19. Completeness of General Solutions to Axisymmetric Problems of Transversely Isotropic Body

    王炜; 徐新生; 王敏中


    In this paper a kind of problems,which are a little wider than the axisymmetric problems of a transversely isotropic elastic body,are considered in a rectangular coordinates system.Two new general solutions of the axisymmetric problems of a transversely isotropic body are concisely obtained in a cylindrical coordinates system.Their completeness is also proved.It is worth while pointing out thai whether the meridional half-section is simply connected or multiply connected,both the new general solutions are single-valued.Using these results eight special general solutions are derived,including some known famous solutions.

  20. Sewing Connection of Step-Step Solution for Singularly Perturbed Problems

    Ming Kang NI; V. I. GURMAN


    In view of singularly perturbed problems with complex inner layer phenomenon,including contrast structures (step-step solution and spike-type solution),corner layer behavior and right-hand side discontinuity,we carry out the process with sewing connection.The presented method of sewing connection for singularly perturbed equations is based on the two points singularly perturbed simple boundary problems.By means of sewing orbit smoothness,we get the uniformly valid solution in the whole interval.It is easy to prove the existence of solutions and deal with the high dimensional singularly perturbed problems.

  1. An Approximate Solution for Spherical and Cylindrical Piston Problem

    S K Singh; V P Singh


    A new theory of shock dynamics (NTSD) has been derived in the form of a finite number of compatibility conditions along shock rays. It has been used to study the growth and decay of shock strengths for spherical and cylindrical pistons starting from a non-zero velocity. Further a weak shock theory has been derived using a simple perturbation method which admits an exact solution and also agrees with the classical decay laws for weak spherical and cylindrical shocks.

  2. A probabilistic solution of robust H∞ control problem with scaled matrices

    Xie, R.; Gong, J. Y.


    This paper addresses the robust H∞ control problem with scaled matrices. It is difficult to find a global optimal solution for this non-convex optimisation problem. A probabilistic solution, which can achieve globally optimal robust performance within any pre-specified tolerance, is obtained by using the proposed method based on randomised algorithm. In the proposed method, the scaled H∞ control problem is divided into two parts: (1) assume the scaled matrices be random variables, the scaled H∞ control problem is converted to a convex optimisation problem for the fixed sample of the scaled matrix and a optimal solution corresponding to the fixed sample is obtained; (2) a probabilistic optimal solution is obtained by using the randomised algorithm based on a finite number N optimal solutions, which are obtained in part (1). The analysis shows that the worst case complexity of proposed method is a polynomial.

  3. Reproduction of solutions in the plane problem on motion of a free-boundary fluid

    Karabut, E. A.; Zhuravleva, E. N.


    This study is devoted to finding exact solutions of the plane unsteady problem on the motion of an ideal incompressible free-boundary fluid. A certain procedure of reproduction making it possible to obtain a two-parametrical family of new exact solutions from one known solution is proposed.

  4. Solutions of Multi Objective Fuzzy Transportation Problems with Non-Linear Membership Functions

    Dr. M. S. Annie Christi


    Full Text Available Multi-objective transportation problem with fuzzy interval numbers are considered. The solution of linear MOTP is obtained by using non-linear membership functions. The optimal compromise solution obtained is compared with the solution got by using a linear membership function. Some numerical examples are presented to illustrate this.

  5. Connectedness of G-proper Efficient Solution Set for Multiobjective Programming Problem

    KONG Xiang-qing


    In this paper, we investigate the connectedness of G-proper efficient solution set for multiobjective programming problem. It is shown that the G-proper efficient solution set is connected if objective functions are convex. A sufficient condition for the connectedness of G-proper efficient solution set is established when objective functions are strictly quasiconvex.




    This paper considers the pointwise estimate of the solutions to Cauchy problem for quasilin-ear hyperbolic systems, which bases on the existence of the solutions by using the fundamentalsolutions. It gives a sharp pointwise estimates of the solutions on domain under consideration.Specially, the estimate is precise near each characteristic direction.

  7. Analytical Solutions to Non-linear Mechanical Oscillation Problems

    Kaliji, H. D.; Ghadimi, M.; Barari, Amin


    In this paper, the Max-Min Method is utilized for solving the nonlinear oscillation problems. The proposed approach is applied to three systems with complex nonlinear terms in their motion equations. By means of this method, the dynamic behavior of oscillation systems can be easily approximated u...

  8. Creativity, Problem Solving, and Solution Set Sightedness: Radically Reformulating BVSR

    Simonton, Dean Keith


    Too often, psychological debates become polarized into dichotomous positions. Such polarization may have occurred with respect to Campbell's (1960) blind variation and selective retention (BVSR) theory of creativity. To resolve this unnecessary controversy, BVSR was radically reformulated with respect to creative problem solving. The reformulation…

  9. Wicked problems and clumsy solutions: Planning as expectation management

    Hartmann, T.


    In 1973, Horst W Rittel and Malvin A Webber introduced the term ‘wicked problem’ in planning theory. They describe spatial planning as dealing with inherent uncertainty, complexity and inevitable normativity. This contribution picks up the concept of wicked problems, reflects on it from

  10. Wicked problems and clumsy solutions: Planning as expectation management

    Hartmann, T.


    In 1973, Horst W Rittel and Malvin A Webber introduced the term ‘wicked problem’ in planning theory. They describe spatial planning as dealing with inherent uncertainty, complexity and inevitable normativity. This contribution picks up the concept of wicked problems, reflects on it from a planning-t

  11. Reforming the Review Process: Right Problem, Wrong Solution.

    Meier, Kenneth J.


    Responds to recent scathing criticism of the peer review process of scholarly publishing. Identifies three main problems with reviewers and editors: unresponsiveness, inconsistency, and indecisiveness. Discusses the pros and cons of several proposed publishing reforms including multiple submissions, establishing clearer and more consistent…

  12. The solution of location problems with certain existing facility structures

    Juel, Henrik; Love, Robert F.


    It is known that in the Euclidean distance case, the optimal minisum location of a new facility in relation to four existing facilities is at the intersection of the two lines joining two pairs of the facilities. The authors extend this concept to minisum problems having any even number of existi...

  13. Technology: The Problem or the Solution to Childhood Obesity

    Silverstone, Susan; Teatum, Jim


    One-third of the population of US children is considered obese and two-thirds of the adult population falls into the same category. These figures have tripled over the last 30 years. This demonstrates that the existing strategies to combat obesity do not work and it is time to look for alternatives. The recommendation is to turn the problem into a…

  14. New Problems and Solutions in Basic University Teaching

    Olesen, Mogens Nørgaard


    Because the syllabus in mathematics in Danish high schools has been weakened substantially over the last decade, the university students have experienced new serious problems in their first year learning. This has had the consequence that many students dropped out of their studies and that many...

  15. To the editor: Two solutions in search of a problem

    Two recent articles in Hepatology suggest that the problems of fructose-induced fibrosis severity in patients with nonalcoholic fatty liver disease (NAFLD) or nonalcoholic hepatic steatosis (NASH) could be solved if their exposure were limited either directly through diet or indirectly through curcu...

  16. Robust Solutions of Optimization Problems Affected by Uncertain Probabilities

    Ben-Tal, A.; den Hertog, D.; De Waegenaere, A.M.B.; Melenberg, B.; Rennen, G.


    In this paper we focus on robust linear optimization problems with uncertainty regions defined by ø-divergences (for example, chi-squared, Hellinger, Kullback-Leibler). We show how uncertainty regions based on ø-divergences arise in a natural way as confidence sets if the uncertain parameters contai

  17. Multi-party arbitration in international trade: problems and solutions

    Siig, Kristina


    of dispute resolution in a multy-party set-up. Both the possible legal bases and the problems encountered are considere. It is concluded that arbitration is still the only real option to the parties in international business disputes and that many of the shortcomings  may be contered by skilful drafting...

  18. Behaviorism: part of the problem or part of the solution.

    Holland, J G


    The form frequently taken by behavior-modification programs is analyzed in terms of the parent science, Behaviorism. Whereas Behaviorism assumes that behavior is the result of contingencies, and that lasting behavior change involves changing the contingencies that give rise to and support the behavior, most behavior-modification programs merely arrange special contingencies in a special environment to eliminate the "problem" behavior. Even when the problem behavior is as widespread as alcoholism and crime, behavior modifiers focus on "fixing" the alcoholic and the criminal, not on changing the societal contingencies that prevail outside the therapeutic environment and continue to produce alcoholics and criminals. The contingencies that shape this method of dealing with behavioral problems are also analyzed, and this analysis leads to a criticism of the current social structure as a behavior control system. Although applied behaviorists have frequently focused on fixing individuals, the science of Behaviorism provides the means to analyze the structures, the system, and the forms of societal control that produce the "problems". PMID:649524

  19. Behaviorism: part of the problem or part of the solution.

    Holland, J G


    The form frequently taken by behavior-modification programs is analyzed in terms of the parent science, Behaviorism. Whereas Behaviorism assumes that behavior is the result of contingencies, and that lasting behavior change involves changing the contingencies that give rise to and support the behavior, most behavior-modification programs merely arrange special contingencies in a special environment to eliminate the "problem" behavior. Even when the problem behavior is as widespread as alcoholism and crime, behavior modifiers focus on "fixing" the alcoholic and the criminal, not on changing the societal contingencies that prevail outside the therapeutic environment and continue to produce alcoholics and criminals. The contingencies that shape this method of dealing with behavioral problems are also analyzed, and this analysis leads to a criticism of the current social structure as a behavior control system. Although applied behaviorists have frequently focused on fixing individuals, the science of Behaviorism provides the means to analyze the structures, the system, and the forms of societal control that produce the "problems".

  20. Robust Solutions of Optimization Problems Affected by Uncertain Probabilities

    Ben-Tal, A.; den Hertog, D.; De Waegenaere, A.M.B.; Melenberg, B.; Rennen, G.


    In this paper we focus on robust linear optimization problems with uncertainty regions defined by ø-divergences (for example, chi-squared, Hellinger, Kullback-Leibler). We show how uncertainty regions based on ø-divergences arise in a natural way as confidence sets if the uncertain parameters

  1. Robust solutions of optimization problems affected by uncertain probabilities

    Ben-Tal, A.; den Hertog, D.; De Waegenaere, A.M.B.; Melenberg, B.; Rennen, G.


    In this paper we focus on robust linear optimization problems with uncertainty regions defined by φ-divergences (for example, chi-squared, Hellinger, Kullback–Leibler). We show how uncertainty regions based on Φ-divergences arise in a natural way as confidence sets if the uncertain parameters

  2. Robust Solutions of Optimization Problems Affected by Uncertain Probabilities

    A. Ben-Tal (Aharon); D. den Hertog; A.M.B. De Waegenaere; B. Melenberg; G. Rennen


    htmlabstract Samenvatting In this paper we focus on robust linear optimization problems with uncertainty regions defined by ø-divergences (for example, chi-squared, Hellinger, Kullback-Leibler). We show how uncertainty regions based on ø-divergences arise in a natural way as confidence sets if the

  3. The solution of location problems with certain existing facility structures

    Juel, Henrik; Love, Robert F.


    It is known that in the Euclidean distance case, the optimal minisum location of a new facility in relation to four existing facilities is at the intersection of the two lines joining two pairs of the facilities. The authors extend this concept to minisum problems having any even number of existing...... facilities and characterized by generalized distance norms...

  4. Drama That Delivers: Real-Life Problems, Students' Solutions.

    Hery, Nancy Duffy

    Drama and role playing are effective ways for teachers, school counselors, and other individuals who work with young people to teach and discuss sensitive issues. The eight plays in this publication are designed to help middle school students develop critical-thinking, problem-solving, and logical decision-making skills. The eight scripts use a…

  5. Similarity of solution branches for two-point semilinear problems

    Philip Korman


    Full Text Available For semilinear autonomous two-point problems, we show that all Neumann branches and all Dirichlet branches with odd number of interior roots have the same shape. On the other hand, Dirichlet branches with even number of roots may look differently. While this result has been proved previously by Schaaf cite{S}, our approach appears to be simpler.

  6. Expert and Novice Solutions of Genetic Pedigree Problems.

    Hackling, Mark W.; Lawrence, Jeanette A.


    Compares experts', advanced students', and novice students' use of genetics knowledge to generate and test hypotheses while solving genetic pedigree problems. Reports that experts identified more critical cues, tested more hypotheses, were more rigorous in the falsification of alternative hypotheses, and were more flexible to their solving…


    Koptev, A.V.


    Full Text Available On the paper under consideration we propose an   approach to the solution of practical problems of fluid mechanics based on the Navier – Stokes equations for viscous incompressible fluid flow. As a result, the solution of the governing equations is reduced to the solution of five simple tasks. Each of these separate tasks is considered using known methods of mathematical physics and differential equations. As a result, the application of the proposed method provides the ability for analytical and approximate analytical solutions 2D and 3D Navier - Stokes equations and constructing   solutions for specific practical problems.

  8. Computational experiment on the numerical solution of some inverse problems of mathematical physics

    Vasil'ev, V. I.; Kardashevsky, A. M.; Sivtsev, PV


    In this article the computational experiment on the numerical solution of the most popular linear inverse problems for equations of mathematical physics are presented. The discretization of retrospective inverse problem for parabolic equation is performed using difference scheme with non-positive weight multiplier. Similar difference scheme is also used for the numerical solution of Cauchy problem for two-dimensional Laplace equation. The results of computational experiment, performed on model problems with exact solution, including ones with randomly perturbed input data are presented and discussed.

  9. Existence of solutions to boundary value problem of fractional differential equations with impulsive

    Weihua JIANG


    Full Text Available In order to solve the boundary value problem of fractional impulsive differential equations with countable impulses and integral boundary conditions on the half line, the existence of solutions to the boundary problem is specifically studied. By defining suitable Banach spaces, norms and operators, using the properties of fractional calculus and applying the contraction mapping principle and Krasnoselskii's fixed point theorem, the existence of solutions for the boundary value problem of fractional impulsive differential equations with countable impulses and integral boundary conditions on the half line is proved, and examples are given to illustrate the existence of solutions to this kind of equation boundary value problems.

  10. Counting solutions for the N -queens and Latin-square problems by Monte Carlo simulations.

    Zhang, Cheng; Ma, Jianpeng


    We apply Monte Carlo simulations to count the numbers of solutions of two well-known combinatorial problems: the N -queens problem and Latin-square problem. The original system is first converted to a general thermodynamic system, from which the number of solutions of the original system is obtained by using the method of computing the partition function. Collective moves are used to further accelerate sampling: swap moves are used in the N -queens problem and a cluster algorithm is developed for the Latin squares. The method can handle systems of 10;{4}degrees of freedom with more than 10;{10,000} solutions.

  11. Common problems and coping solutions of university students in Taiwan

    Mei-Chin Lin


    Full Text Available University life of today is full of challenges. News of school involved bad incidents has all become too common. In Taiwan, students are also faced with many pressures and problems. Problems such as academic stress, future job uncertainty, and interpersonal relationships are just some of the interrelated complications easily found in universities. To address this issue, the current mixed-method study uses a series of focus group sessions in order to solicit the various issues surrounding students’ day to day in-campus life challenges and their corresponding coping strategies. A survey questionnaire was then formulated from the results of the focus group sessions. A total of 123 valid surveys were collected. Data collected were analyzed together with their corresponding demographical backgrounds such as: gender, year level of study, place of living, working or non-working students, and course of study. Results show that the common students’ related complications are health problems, future career issues, lessons and examinations, learning difficulties, self-efficacy issues, interpersonal difficulties, time management, and stress causing issues. Statistical analyses were accomplished resulting to significant students’ school problems determining background factors such as students’ course of study, gender, working or non-working students, and place of living. While no significant differences were found on the common students’ coping strategies. Lastly, there seems to be a high correlation between the students’ problems and coping strategies within the stress causing issues, suggesting that stress related issues to be the root cause of major complications for university students in Taiwan.

  12. Approximate solutions to infinite dimensional LQ problems over infinite time horizon

    PAN; Liping; ZHANG; Xu; CHEN; Qihong


    This paper is addressed to develop an approximate method to solve a class of infinite dimensional LQ optimal regulator problems over infinite time horizon. Our algorithm is based on a construction of approximate solutions which solve some finite dimensional LQ optimal regulator problems over finite time horizon, and it is shown that these approximate solutions converge strongly to the desired solution in the double limit sense.

  13. Multiple positive solutions for Kirchhoff type problems involving concave and convex nonlinearities in R^3

    Xiaofei Cao


    Full Text Available In this article, we consider the multiplicity of positive solutions for a class of Kirchhoff type problems with concave and convex nonlinearities. Under appropriate assumptions, we prove that the problem has at least two positive solutions, moreover, one of which is a positive ground state solution. Our approach is mainly based on the Nehari manifold, Ekeland variational principle and the theory of Lagrange multipliers.

  14. Solution of dynamic contact problems by implicit/explicit methods. Final report

    Salveson, M.W.; Taylor, R.L. [California Univ., Berkeley, CA (United States). Dept. of Civil and Environmental Engineering


    The solution of dynamic contact problems within an explicit finite element program such as the LLNL DYNA programs is addressed in the report. The approach is to represent the solution for the deformation of bodies using the explicit algorithm but to solve the contact part of the problem using an implicit approach. Thus, the contact conditions at the next solution state are considered when computing the acceleration state for each explicit time step.

  15. Technological Solutions to Social and Citizen Problems. The Case of Civic and Public Challenges in Mexico



    This paper describes the process of civic innovation that, based on technological solutions and open initiatives, the civic society’s organization Codeando México suggests for the attention and solution of social and civic problems in Mexico. The Retos Cívicos (Civic Challenges) and Retos Públicos (Public Challenges) initiatives are addressed and described as experiences of innovation in the implementation of technological strategies for the solution of social and civic problems. A reflection...

  16. Implementation of Video Streaming in Urban VANETs

    Selvakanmani Nandakumar


    Full Text Available Streaming applications will rapidly develop and contribute a significant amount of traffic in the near future. A problem, scarcely addressed so far, is how to distribute video streaming traffic from one source to all nodes in an urban vehicular network. This problem significantly differs from previous work on broadcast and multicast in ad hoc networks because of the highly dynamic topology of vehicular networks and the strict delay requirements of streaming applications. We present a solution for inter vehicular communications, called Streaming Urban Video (SUV. The advantages of using SUV are: 1 Fully distributed and dynamically adapts to topology changes, and 2 leverages the characteristics of streaming applications to yield a highly efficient, cross-layer solution.

  17. Structure of Matter An Introductory Course with Problems and Solutions

    Rigamonti, Attilio


    This is the second edition of this textbook, the original of which was published in 2007. Initial undergraduate studies in physics are usually in an organized format devoted to elementary aspects, which is then followed by advanced programmes in specialized fields. A difficult task is to provide a formative introduction in the early period, suitable as a base for courses more complex, thus bridging the wide gap between elementary physics and topics pertaining to research activities. This textbook remains an endeavour toward that goal, and is based on a mixture of simplified institutional theory and solved problems. In this way, the hope is to provide physical insight, basic knowledge and motivation, without impeding advanced learning. The choice has been to limit the focus to key concepts and to those aspects most typical of atoms, molecules and compounds, by looking at the basic, structural components, without paying detailed attention to the properties possessed by them. Problems are intertwined with formal...


    May, C; Allen Smith, A


    The Model 9975 Shipping Package is the latest in a series (9965, 9968, etc.) of radioactive material shipping packages that have been the mainstay for shipping radioactive materials for several years. The double containment vessels are relatively simple designs using pipe and pipe cap in conjunction with the Chalfont closure to provide a leak-tight vessel. The fabrication appears simple in nature, but the history of fabrication tells us there are pitfalls in the different fabrication methods and sequences. This paper will review the problems that have arisen during fabrication and precautions that should be taken to meet specifications and tolerances. The problems and precautions can also be applied to the Models 9977 and 9978 Shipping Packages.

  19. Structural qualia: a solution to the hard problem of consciousness

    Kristjan eLoorits


    Full Text Available The hard problem of consciousness has been often claimed to be unsolvable by the methods of traditional empirical sciences. It has been argued that all the objects of empirical sciences can be fully analyzed in structural terms but that consciousness is (or has something over and above its structure. However, modern neuroscience has introduced a theoretical framework in which also the apparently non-structural aspects of consciousness, namely the so called qualia or qualitative properties, can be analyzed in structural terms. That framework allows us to see qualia as something compositional with internal structures that fully determine their qualitative nature. Moreover, those internal structures can be identified which certain neural patterns. Thus consciousness as a whole can be seen as a complex neural pattern that misperceives some of its own highly complex structural properties as monadic and qualitative. Such neural pattern is analyzable in fully structural terms and thereby the hard problem is solved.

  20. Structure of Matter An Introductory Course with Problems and Solutions

    Rigamonti, Attilio


    This is the second edition of this textbook, the original of which was published in 2007. Initial undergraduate studies in physics are usually in an organized format devoted to elementary aspects, which is then followed by advanced programmes in specialized fields. A difficult task is to provide a formative introduction in the early period, suitable as a base for courses more complex, thus bridging the wide gap between elementary physics and topics pertaining to research activities. This textbook remains an endeavour toward that goal, and is based on a mixture of simplified institutional theory and solved problems. In this way, the hope is to provide physical insight, basic knowledge and motivation, without impeding advanced learning. The choice has been to limit the focus to key concepts and to those aspects most typical of atoms, molecules and compounds, by looking at the basic, structural components, without paying detailed attention to the properties possessed by them. Problems are intertwined with formal...

  1. Proper use of medical language: Main problems and solutions.

    Aleixandre-Benavent, R; Valderrama Zurián, J C; Bueno-Cañigral, F J


    Medical language should be characterized by its precision, emotional neutrality and stability. The effective communication of results of scientific studies depends on compliance with current standards of drafting and style; texts with defects can hinder interest in the findings. In this study, we discuss some of the most common problems and errors in medical language, including the abuse of abbreviations and foreign words, the use of improper words, syntax errors and solecisms, the most common errors in titles and the abuse of capital letters and the gerund. Investigators have effective tools for dealing with these problems, such as quality texts, critical dictionaries of questions and difficulties with the Spanish language and various drafting and style manuals. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  2. Majorana solutions to the two-electron problem

    Esposito, S


    A review of the known different methods and results devised to study the two-electron atom problem, appeared in the early years of quantum mechanics, is given, with particular reference to the calculations of the ground state energy of helium. This is supplemented by several, unpublished results obtained around the same years by Ettore Majorana, which results did not convey in his published papers on the argument, and thus remained unknown until now. Particularly interesting, even for current research in atomic and nuclear physics, is a general variant of the variational method, developed by Majorana in order to take directly into account, already in the trial wavefunction, the action of the full Hamiltonian operator of a given quantum system. Moreover, notable calculations specialized to the study of the two-electron problem show the introduction of the remarkable concept of an effective nuclear charge different for the two electrons (thus generalizing previous known results), and an application of the pertu...

  3. Professional Self-determination of Modern Teenagers: Problems and Solutions

    Ilyina O.B.,


    Full Text Available Professional self-determination in adolescence for many years has been one of the hot topics of psychological theory and practice. Research in the field of personal and professional self-determination, career choice, continues to be a priority. Professional self-determination is part of the general process of socialization of adolescents, a necessary condition for their success and competitiveness in today's socio-economic realities. And it raises the question of what should be psychological and educational support in these conditions? Problems of career choice are considered on three sides: in the context of the social situation in which there are modern teenagers; from the perspective of adolescents themselves, choosing the profession; taking into account the peculiarities of psycho-pedagogical support of professional self-determination of teenagers nowadays. Analysis of problems leads us to the possible ways of solving them, and the need to build a new model of career guidance

  4. Structural qualia: a solution to the hard problem of consciousness

    Loorits, Kristjan


    The hard problem of consciousness has been often claimed to be unsolvable by the methods of traditional empirical sciences. It has been argued that all the objects of empirical sciences can be fully analyzed in structural terms but that consciousness is (or has) something over and above its structure. However, modern neuroscience has introduced a theoretical framework in which also the apparently non-structural aspects of consciousness, namely the so called qualia or qualitative properties, can be analyzed in structural terms. That framework allows us to see qualia as something compositional with internal structures that fully determine their qualitative nature. Moreover, those internal structures can be identified which certain neural patterns. Thus consciousness as a whole can be seen as a complex neural pattern that misperceives some of its own highly complex structural properties as monadic and qualitative. Such neural pattern is analyzable in fully structural terms and thereby the hard problem is solved. PMID:24672510

  5. [Reference standards in diagnostic research: problems and solutions].

    de Groot, Joris A H; Reitsma, Johannes B; Moons, Karel G M


    The accuracy of diagnostic tests is of utmost importance as biased test results may lead to wrong decisions in clinical practice. In diagnostic accuracy research the results of a diagnostic test, model or strategy are compared to those of the reference standard, i.e. the best available method to determine whether a certain condition or disease is present or absent. Problems with the reference standard lead to biased test results. The umbrella term for this is 'verification bias'. Verification bias arises if the reference standard cannot be applied to all patients, if investigators use different reference standards or simply because there is no reference standard. Correction of these problems is often possible, and, if it is applied in a transparent and reproducible fashion it will deliver useful diagnostic information. Clinicians who use a diagnostic test should take possible verification bias into account.

  6. Beyond $\\Lambda$CDM: Problems, solutions, and the road ahead

    Bull, Philip; Adamek, Julian; Baker, Tessa; Bellini, Emilio; Jiménez, Jose Beltrán; Bentivegna, Eloisa; Camera, Stefano; Clesse, Sébastien; Davis, Jonathan H; Di Dio, Enea; Enander, Jonas; Finelli, Fabio; Heavens, Alan; Heisenberg, Lavinia; Hu, Bin; Llinares, Claudio; Maartens, Roy; Mörtsell, Edvard; Nadathur, Seshadri; Noller, Johannes; Pasechnik, Roman; Pawlowski, Marcel S; Pereira, Thiago S; Quartin, Miguel; Ricciardone, Angelo; Riemer-Sørensen, Signe; Rinaldi, Massimiliano; Sakstein, Jeremy; Saltas, Ippocratis D; Salzano, Vincenzo; Sawicki, Ignacy; Solomon, Adam R; Spolyar, Douglas; Starkman, Glenn D; Steer, Danièle; Tereno, Ismael; Verde, Licia; Villaescusa-Navarro, Francisco; von Strauss, Mikael; Winther, Hans A


    Despite its continued observational successes, there is a persistent (and growing) interest in extending cosmology beyond the standard model, $\\Lambda$CDM. This is motivated by a range of apparently serious theoretical issues, involving such questions as the cosmological constant problem, the particle nature of dark matter, the validity of general relativity on large scales, the existence of anomalies in the CMB and on small scales, and the predictivity and testability of the inflationary paradigm. In this paper, we summarize the current status of $\\Lambda$CDM as a physical theory, and review investigations into possible alternatives along a number of different lines, with a particular focus on highlighting the most promising directions. While the fundamental problems are proving reluctant to yield, the study of alternative cosmologies has led to considerable progress, with much more to come if hopes about forthcoming high-precision observations and new theoretical ideas are fulfilled.

  7. Special relativity. An introduction with 200 problems and solutions

    Tsamparlis, Michael [Athens Univ., Zografos (Greece). Dept. of Astrophysics, Astronomy and Mechanics


    This textbook develops Special Relativity in a systematic way assuming no prior knowledge of Relativity; however the student is assumed to be familiar with the basics of the standard vector calculus. The approach is structural in the sense that it develops Special Relativity in Minkowski space following the same steps with the development of Newtonian Physics in Euclidian space. A second characteristic of the book is that it discusses the mathematics of the theory independently of the physical principles, so that the reader will appreciate its role in the development of the physical theory. The book is intended to be used both as a text-book for a teaching course in Special Relativity but also as a reference book for the future. In that respect it is linked to an online repository with more than 500 problems, carefully classified according to subject area and solved in detail, providing an independent problem book on Special Relativity. (orig.)

  8. Image Based Solution to Occlusion Problem for Multiple Robots Navigation

    Taj Mohammad Khan


    Full Text Available In machine vision, occlusions problem is always a challenging issue in image based mapping and navigation tasks. This paper presents a multiple view vision based algorithm for the development of occlusion-free map of the indoor environment. The map is assumed to be utilized by the mobile robots within the workspace. It has wide range of applications, including mobile robot path planning and navigation, access control in restricted areas, and surveillance systems. We used wall mounted fixed camera system. After intensity adjustment and background subtraction of the synchronously captured images, the image registration was performed. We applied our algorithm on the registered images to resolve the occlusion problem. This technique works well even in the existence of total occlusion for a longer period.

  9. Proposal of bimodal solution for urban vehicular contamination problem

    Gilberto Osorio Gómez


    Full Text Available In research field of alternative solutions to internal combustion engine vehicles, the Politecnico di Milano has developed a design and manufacturing project for an adaptable electro-mechanical kit intended to transform a city car with en-dothermic propulsion into a bimodal one, using existent technologies and innovative solutions. This project involves mechanical and electrical competences in order to develop a new transmission parallel to the current endothermic propulsion and its control system. This paper describes, in general, the developed procedure to obtain the final proto-type. At first, the requirements and constraints to fulfil a standard transport urban cycle has been established and the vehicle to modify was selected, in this case the Fiat Grande Punto. Next, new components and the required space to their installation have been identified and specified, whilst mechanical components were designed and manufactured. Instruments of reverse engineering and virtual prototyping have been employed to carry out the geometrical models, simulations and layouts and to identify useful spaces in the vehicle. Finally, general modifications, installation of new components, implementation of control and data acquisition system, fine-tuning and check of specifications fulfilment have been carried out. A 30 km range working in electrical mode, with a top speed of 70 km/h, is assured with the developed kit. These results demonstrate the feasibility to implement a forward bimodal propulsion system into a com-mercial city car with a little invasive commercial kit, and now, the Politecnico is working at its industrialization and im-plementation to different models of city cars. Regione Lombardia (Regional government in Italy has funded this project as an investigation oriented to find new solutions to sustainable transport and reduction of environmental pollution.

  10. Fast Combinatorial Algorithm for the Solution of Linearly Constrained Least Squares Problems

    Van Benthem, Mark H.; Keenan, Michael R.


    A fast combinatorial algorithm can significantly reduce the computational burden when solving general equality and inequality constrained least squares problems with large numbers of observation vectors. The combinatorial algorithm provides a mathematically rigorous solution and operates at great speed by reorganizing the calculations to take advantage of the combinatorial nature of the problems to be solved. The combinatorial algorithm exploits the structure that exists in large-scale problems in order to minimize the number of arithmetic operations required to obtain a solution.

  11. Existence of Solutions of a Riccati Differential System from a General Cumulant Control Problem

    Stanley R. Liberty


    Full Text Available We study a system of infinitely many Riccati equations that arise from a cumulant control problem, which is a generalization of regulator problems, risk-sensitive controls, minimal cost variance controls, and k-cumulant controls. We obtain estimates for the existence intervals of solutions of the system. In particular, new existence conditions are derived for solutions on the horizon of the cumulant control problem.

  12. Priming children's and adults' analogical problem solutions with true and false memories.

    Howe, Mark L; Threadgold, Emma; Norbury, Jenna; Garner, Sarah; Ball, Linden J


    We investigated priming of analogical problem solutions with true and false memories. Children and adults were asked to solve nine verbal proportional analogies, three of which had been primed by Deese-Roediger-McDermott (DRM) lists where the critical lure (and problem solution) was presented as the initial word in the list (true memory priming), three of which were primed by DRM lists whose critical lures were the solution to the verbal proportional analogies (false memory priming), and three of which were unprimed. We controlled for age differences in solution rates (knowledge base) in order to examine developmental differences in speed of processing. As anticipated, the results showed that adults completed the problems significantly faster than children. Furthermore, both children and adults solved problems primed with false memories significantly faster than either those primed with true memories or unprimed problems. For both age groups, there was no significant difference between solution times for unprimed and true primed problems. These findings demonstrate that (a) priming of problem solutions extends to verbal proportional analogies, (b) false memories are more effective at priming problem solutions than true memories, and (c) there are clear positive consequences to the production of false memories. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. A review on adsorption heat pump: Problems and solutions

    Demir, Hasan; MOBEDI, Moghtada; Ülkü, Semra


    Adsorption heat pumps have considerably sparked attentions in recent years. The present paper covers the working principle of adsorption heat pumps, recent studies on advanced cycles, developments in adsorbent-adsorbate pairs and design of adsorbent beds. The adsorbent-adsorbate pair features for in order to be employed in the adsorption heat pumps are described. The adsorption heat pumps are compared with the vapor compression and absorption heat pumps. The problems and troubles of adsorptio...

  14. Intensive Reading Course:problems and so-lutions



    @@ 1.The analysis of the problems As far as we know, the approach of teaching intensive reading in many senior high schools is commonly called the"Grammar-Translation Approach".Themethods can be briefly described as follows: before going to class.Students arcusually asked to prepare the new lessons, that is, to read the text, look up the meaning of the new vocabulary in the word list or in a dictionary, and underline words or sentences they don't understand.


    Dema, Dmitry; Feshchenko, Natalya


    The theoretical and practical aspects of using a treasury management system for servicing of local budgets are considered; the role of treasury bodies in routine management of local finances is defined. Current problems of treasury-based execution of local spending budgets are investigated and main deregulating factors affecting the procedure of cash execution of budgets are arranged in a system.Ways to improve budget funds management at the local level are proposed including: improvement of ...

  16. New confining force solution of QCD axion domain wall problem

    Barr, S. M.; Kim, Jihn E.


    The serious cosmological problems created by the axion-string/axion-domain-wall system in standard axion models are alleviated by positing the existence of a new confining force. The instantons of this force can generate an axion potential that erases the axion strings long before QCD effects become important, thus preventing QCD-generated axion walls from ever appearing. Axion walls generated by the new confining force would decay so early as not to contribute significantly to the energy in ...

  17. Binge Drinking – Nationwide Problem, Local Solutions


    This podcast is based on the January 2012 CDC Vital Signs report. One in six adults binge drinks about four times a month. It's a problem nationwide but community-based strategies, such as reducing access to alcohol and increasing the price, can prevent binge drinking.  Created: 1/3/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 1/3/2012.

  18. Electric Vehicle Routing Problems : models and solution approaches

    Montoya, Jose-Alejandro


    Electric vehicles (evs) are one of the most promising technologies to reduce the greenhouse gas emissions. For this reason, the use of evs in service operations has dramatically increased in recent years. Despite their environmental benefits, evs still face technical constraints such as short autonomy and long charging times. Taking into account these constraints when planning ev operations leads to a new breed of vehicle routing problems (vrps), known as electricVrps (evrps). In addition, to...

  19. Mobilizing Black America: Solutions to Black Health Problems


    the most obese ethnic group in America. Too many black children are overweight because black adults feed them a steady diet of fatty and salty foods...start and elementary school children in the Early and Periodic Screening, Diagnosis, and Treatment (EPSDT) program. EPSDT has been instrumental in...blood cholesterol, obesity , unhealthy diets, and smoking are the leading causes (major risk factors) of these killers. The underlying problems associated

  20. On the singularities of solutions to singular perturbation problems

    Fruchard, A [Laboratoire de Mathematiques, Informatique et Applications, Faculte des Sciences et Techniques, Universite de Haute Alsace, 4 rue des Freres Lumiere, 68093 Mulhouse cedex (France); Schaefke, R [Departement de Mathematiques, Universite Louis Pasteur, 7 rue Rene-Descartes, 67084 Strasbourg cedex (France)


    We consider a singularly perturbed complex first order ODE {epsilon}u ' {phi}(x, u, a, {epsilon}), x, u element of C, {epsilon} > 0 is a small complex parameter and a element of C is a control parameter. It is proven that the singularities of some solutions are regularly spaced and that they move from one to the next as a runs about a loop of index one around a value of overstability. This gives a positive answer to a question of J. L. Callot.


    Sharma Pankaj


    Full Text Available Neem has become important in the global context today because it offers answers to the major concerns facing mankind. Azadirachta indica is a fast growing evergreen popular tree found commonly in India, Africa and America. This review gives a bird’s eye view mainly on the biological activity and its preventive-promotive medicinal uses and applications over all this review also tell you that how the “neem is the one solution of thousand problems”, like Antiallergenic, antidermatic, antifeedent, antifungal, anti-inflammatory, antipyorrhoeic, antiscabic, cardiac, diuretic, insecticidal, larvicidal, nematicidal, spermicidal and other biological activities.

  2. Applying Bayesian Inference to Galileon Solutions of the Muon Problem

    Lamm, Henry


    We derive corrections to atomic energy levels from disformal couplings in Galileon theories. Through Bayesian inference, we constrain the cut-off radii and Galileon scale via these corrections. To connect different atomic systems, we assume the various cut-off radii related by a 1-parameter family of solutions. This introduces a new parameter $\\alpha$ which is also constrained. In this model, we predict shifts to muonic helium of $\\delta E_{He^3}=1.97^{+9.28}_{-1.87}$ meV and $\\delta E_{He^4}=1.69^{+9.25}_{-1.61}$ meV.

  3. Collaboration Results - Applying Technical Solutions To Environmental Remediation Problems

    Boyd, G.; Fiore, J.; Walker, J.; DeRemer, C.; Wight, E.


    Within the Department of Energy's Office of Environmental Management (EM), the Office of Science and Technology (OST) identifies and develops innovative technologies that accelerate cleanup of high-priority environmental contamination problems and enable EM closure sites to meet closure schedules. OST manages an integrated research and development program that is essential to completing timely and cost-effective cleanup and stewardship of DOE sites. While innovative technologies can make significant contributions to the cleanup process, in some cases, EM has encountered unexpected barriers to their implementation. Technical obstacles are expected, but administrative challenges-such as regulatory, organizational, and stakeholder issues-must also be addressed. OST has found that collaborative needs identification and problem solving are essential components in overcoming these barriers. Collaboration helps EM meet its cleanup goals, close sites, and reduce the overall cost of cleanup at DOE sites nationwide. This paper presents examples of OST's collaboration efforts that expedite site closure and solve specific cleanup problems at EM sites.

  4. Multiple Revolution Solutions for the Perturbed Lambert Problem using the Method of Particular Solutions and Picard Iteration

    Woollands, Robyn M.; Read, Julie L.; Probe, Austin B.; Junkins, John L.


    We present a new method for solving the multiple revolution perturbed Lambert problem using the method of particular solutions and modified Chebyshev-Picard iteration. The method of particular solutions differs from the well-known Newton-shooting method in that integration of the state transition matrix (36 additional differential equations) is not required, and instead it makes use of a reference trajectory and a set of n particular solutions. Any numerical integrator can be used for solving two-point boundary problems with the method of particular solutions, however we show that using modified Chebyshev-Picard iteration affords an avenue for increased efficiency that is not available with other step-by-step integrators. We take advantage of the path approximation nature of modified Chebyshev-Picard iteration (nodes iteratively converge to fixed points in space) and utilize a variable fidelity force model for propagating the reference trajectory. Remarkably, we demonstrate that computing the particular solutions with only low fidelity function evaluations greatly increases the efficiency of the algorithm while maintaining machine precision accuracy. Our study reveals that solving the perturbed Lambert's problem using the method of particular solutions with modified Chebyshev-Picard iteration is about an order of magnitude faster compared with the classical shooting method and a tenth-twelfth order Runge-Kutta integrator. It is well known that the solution to Lambert's problem over multiple revolutions is not unique and to ensure that all possible solutions are considered we make use of a reliable preexisting Keplerian Lambert solver to warm start our perturbed algorithm.

  5. A Unified Iterative Treatment for Solutions of Problems of Split Feasibility and Equilibrium in Hilbert Spaces

    Young-Ye Huang


    Full Text Available We at first raise the so called split feasibility fixed point problem which covers the problems of split feasibility, convex feasibility, and equilibrium as special cases and then give two types of algorithms for finding solutions of this problem and establish the corresponding strong convergence theorems for the sequences generated by our algorithms. As a consequence, we apply them to study the split feasibility problem, the zero point problem of maximal monotone operators, and the equilibrium problem and to show that the unique minimum norm solutions of these problems can be obtained through our algorithms. Since the variational inequalities, convex differentiable optimization, and Nash equilibria in noncooperative games can be formulated as equilibrium problems, each type of our algorithms can be considered as a generalized methodology for solving the aforementioned problems.

  6. Problem Solution Project: Transforming Curriculum and Empowering Urban Students and Teachers

    Jarrett, Olga S.; Stenhouse, Vera


    This article presents findings of 6 years of implementing a Problem Solution Project, an assignment influenced by service learning, problem-based learning, critical theory, and critical pedagogy whereby teachers help children tackle real problems. Projects of 135 teachers in an urban certification/master's program were summarized by cohort year…


    N. G. Kulneva


    Full Text Available Summary. Sugar beet is one of the strategic crops for food safety of Russia. The lack of specialized warehouse for harvest does not provide storage of roots for a long time. In the case of a thaw roots that have been defrosted unsuitable for processing. Beet and products of its processing is a good object for the development of microorganisms. Permanent microflora of sugar production are: Bacillus subtilis, Clostridium perfringes, Leuconostoc dextranicum, Torula alba, Pseudomonas fluorescens, Sarcina lutea and other kinds of microorganisms, leading to a problem processing of beet root and reduced quality of sugar. The most dangerous is the slimy bacteriosis is a bacterial disease beet caused by heterofermentative cocci of Leuconostoc (Leuconostoc mesenteroides, L. dextranicum. Product of the vital activity of microorganisms is dextran, which is synthesized from sucrose as a result of dextrany or mucous fermentation and leads to significant technological problems in processing of infected beet. Improving the efficiency of sugar production is connected with decrease in loss of quality of raw material preparation, storing and processing of sugar beet. At sugar plants use a variety of drugs that suppress the growth of pathogenic microflora, but there comes a rapid adaptation of microorganisms, therefore there is a need to implement new products to prevent damage to roots and improve the quality of produced sugar. To resolve this problem experimentally selected bactericidal drug, defined its rational concentration and conditions for the use in sugar beet production. The use of antibacterial drug in the process of extraction allows to increase the purity of diffusion juice 1.3 %, reduce the protein content in it (12.5 %; with the purity of the pure juice increases by 1.1 %, its color index is reduced by 44.7 %.

  8. Lifting solutions to perturbing problems in C*-algebras

    Loring, Terry A


    The nature of C^*-algebras is such that one cannot study perturbation without also studying the theory of lifting and the theory of extensions. Approximation questions involving representations of relations in matrices and C^*-algebras are the central focus of this volume. A variety of approximation techniques are unified by translating them into lifting problems: from classical questions about transitivity of algebras of operators on Hilbert spaces to recent results in linear algebra. One chapter is devoted to Lin's theorem on approximating almost normal matrices by normal matrices. The techn

  9. Inverse Problem Solution in Landmines Detection Based on Active Thermography

    B. Szymanik


    Full Text Available Landmines still affect numerous territories in the whole world and pose a serious threat, mostly to civilians. Widely used non-metallic landmines are undetectable using metal detector. Therefore, there is an urging need to improve methods of detecting such objects. In the present study we introduce relatively new method of landmines' detection: active infrared thermography with microwave excitation. In this paper we present the optimization based method of solving inverse problem for microwave heating. This technique will be used in the reconstruction of detected landmines geometric and material properties.

  10. Solution of inverse localization problem associated to multistatic radar system

    Boutkhil M.


    Full Text Available This work deals with the problem of inverse localization by a target with the aim to retrieve the position of the target, given the intensity and phase of the electromagnetic waves scattered by this object. Assuming the surface cross section to be known as well as the intensity and phase of the scattered waves, the target position was reconstructed through the echo signals scattered of each bistatic. We develop in the same time a multistatic ambiguity function trough bistatic ambiguity function to investigate several fundamental aspects that determine multistatic radar performance. We used a multistatic radar constructed of two bistatic radars, two transmitters and one receiver.

  11. Summary of coal problems and possible geophysics solutions

    Van Schoor, Abraham M


    Full Text Available Plan view of old working Cross section (A–B) Figure 4.1 Schematic plan and sectional views of typical ‘old workings’ delineating previously mined areas This problem typically occurs where active mining encroaches on a previously mined area. Historic... in the unmined blocks between adjacent boreholes, through a tomographic approach. However, the unavoidable range-resolution trade-off associated with methods such as cross-hole radar imaging may require many more boreholes than are economically justified...


    G. P. Itkin


    Full Text Available The article brings up for the discussion main problems standing in the way of development of the mechanical circulatory support (MCS technology. We give a short historical overview of the development of this technology in our country. Classifi cation of MCS systems for medical indications is given; methods and techniques for short-term and long-term therapy with MCS systems are considered. Main directions of the development of MCS methods are discussed. Using the example of personal experience the methods of design and research of MCS systems are investigated.

  13. Asymptotic Solution of the Theory of Shells Boundary Value Problem

    I. V. Andrianov


    Full Text Available This paper provides a state-of-the-art review of asymptotic methods in the theory of plates and shells. Asymptotic methods of solving problems related to theory of plates and shells have been developed by many authors. The main features of our paper are: (i it is devoted to the fundamental principles of asymptotic approaches, and (ii it deals with both traditional approaches, and less widely used, new approaches. The authors have paid special attention to examples and discussion of results rather than to burying the ideas in formalism, notation, and technical details.

  14. Varying-$\\alpha $ Theories and Solutions to the Cosmological Problems

    Barrow, John D; Barrow, John D.; Magueijo, Joao


    If the fine structure constant $\\alpha =e^2/(\\hbar c)$ were to change, then a number of interpretations would be possible, attributing this change either to variations in the electron charge, the dielectric constant of the vacuum, the speed of light, or Planck's constant. All these variations should be operationally equivalent and can be related by changes of standard units. We show how the varying speed of light cosmology recently proposed can be rephrased as a dielectric vacuum theory, similar to the one proposed by Bekenstein. The cosmological problems will therefore also be solved in such a theory.

  15. Oracle SQL Recipes A Problem-solution Approach

    Allen, Grant


    Have you ever been faced with a new type of query to write, or been asked to create an unfamiliar database object? In such situations, you have probably wanted a good, solid example upon which to build, and instead have been forced into the drudgery of parsing railroad-style syntax diagrams in Oracle's manual set. This book frees you from that drudgery by providing tested and working examples of SQL used to solve common problems faced by developers and database administrators on a daily basis. When you're under pressure to get results fast, Oracle SQL Recipes is there at your side. *Example-ba

  16. A Tentative Probe into the Solution of the Listening Problems



    Many students often raise questions,"Why it is so difficult to improve the listening comprehension?" This cannot be solved easily,because listening is a kind of complex and perceptual knowledge process.Listening does not only mean the ability to hear,it is also the ability to capture the information that the language carries through hearing organs and the ability of head.As far as I am concerned,such a problem is related to the complexity of various factors:listening itself covers,the language knowledge proficiency listeners possess,and also it is closely connected with the traditional foreign language style.

  17. An analytic solution to asymmetrical bending problem of diaphragm coupling


    Because rigidity of either hub or rim of diaphragm coupling is much greater than that of the disk, and asymmetrical bending is under the condition of high speed revolution, an assumption is made that each circle in the middle plane before deforma-tion keeps its radius unchanged after deformation, but the plane on which the circle lies has a varying deflecting angle. Based on this assumption, and according to the principle of energy variation, the corresponding Euler's equation can be obtained, which has the primary integral. By neglecting some subsidiary factors, an analytic solution is obtained. Applying these formulas to a hyperbolic model of diaphragm, the results show that the octahedral shear stress varies less along either radial or thickness direction, but fluctu-ates greatly and periodically along circumferential direction. Thus asymmetrical bending significantly affects the material's fatigue.

  18. An exact solution of the slow-light problem

    Rybin, A V; Bishop, A R


    We investigate propagation of a slow-light soliton in atomic vapors and Bose-Einstein condensates described by the nonlinear Lambda-model. We show that the group velocity of the soliton monotonically decreases with the intensity of the controlling laser field, which decays exponentially after the laser is switched off. The shock wave of the vanishing controlling field overtakes the slow soliton and stops it, while the optical information is recorded in the medium in the form of spatially localized polarization. We find an explicit exact solution describing the whole process within the slowly varying amplitude and phase approximation. Our results point to the possibility of addressing spatially localized memory formations and moving these memory bits along the medium in a controllable fashion.

  19. Applying Bayesian inference to Galileon solutions of the muon problem

    Lamm, Henry


    We derive corrections to atomic energy levels from disformal couplings in Galileon theories. Through Bayesian inference, we constrain the cutoff radii and Galileon scale via these corrections. To connect different atomic systems, we assume the various cutoff radii related by a one-parameter family of solutions. This introduces a new parameter α which is also constrained. In this model, we predict shifts to muonic helium of δ EHe3=1.9 7-1.87+9.28 meV and δ EHe4=1.6 9-1.61+9.25 meV as well as for true muonium, δ ETM=0.0 6-0.05+0.46 meV .

  20. Numerical solution of an edge flame boundary value problem

    Shields, Benjamin; Freund, Jonathan; Pantano, Carlos


    We study edge flames for modeling extinction, reignition, and flame lifting in turbulent non-premixed combustion. An adaptive resolution finite element method is developed for solving a strained laminar edge flame in the intrinsic moving frame of reference of a spatially evolving shear layer. The variable-density zero Mach Navier-Stokes equations are used to solve for both advancing and retreating edge flames. The eigenvalues of the system are determined simultaneously (implicitly) with the scalar fields using a Schur complement strategy. A homotopy transformation over density is used to transition from constant- to variable-density, and pseudo arc-length continuation is used for parametric tracing of solutions. Full details of the edge flames as a function of strain and Lewis numbers will be discussed. This material is based upon work supported [in part] by the Department of Energy, National Nuclear Security Administration, under Award Number DE-NA0002374.

  1. Exact Asymptotic Expansion of Singular Solutions for the (2+1-D Protter Problem

    Lubomir Dechevski


    Full Text Available We study three-dimensional boundary value problems for the nonhomogeneous wave equation, which are analogues of the Darboux problems in ℝ2. In contrast to the planar Darboux problem the three-dimensional version is not well posed, since its homogeneous adjoint problem has an infinite number of classical solutions. On the other hand, it is known that for smooth right-hand side functions there is a uniquely determined generalized solution that may have a strong power-type singularity at one boundary point. This singularity is isolated at the vertex of the characteristic light cone and does not propagate along the cone. The present paper describes asymptotic expansion of the generalized solutions in negative powers of the distance to this singular point. We derive necessary and sufficient conditions for existence of solutions with a fixed order of singularity and give a priori estimates for the singular solutions.

  2. A Series Solution of the Cauchy Problem for Turing Reaction-diffusion Model

    L. Päivärinta


    Full Text Available In this paper, the series pattern solution of the Cauchy problem for Turing reaction-diffusion model is obtained by using the homotopy analysis method (HAM. Turing reaction-diffusion model is nonlinear reaction-diffusion system which usually has power-law nonlinearities or may be rewritten in the form of power-law nonlinearities. Using the HAM, it is possible to find the exact solution or an approximate solution of the problem. This technique provides a series of functions which converges rapidly to the exact solution of the problem. The efficiency of the approach will be shown by applying the procedure on two problems. Furthermore, the so-called homotopy-Pade technique (HPT is applied to enlarge the convergence region and rate of solution series given by the HAM.

  3. Environmental and Water Resources Management: Problems and Solutions

    Robert Wenger; Zhifeng Yang


    Environmental problems and issues have no geographical bounds.Many are global in scale;others may be bounded in some manner to a particular region,yet share features with similar problems in other locales throughout the world.It is important,then,for environmental researchers,policymakers,and practitioners to reach across national and cultural boundaries to discuss these issues and learn from each other.For more than 25 years an ongoing international seminar-study tour program initiated by the Environmental and Water Resources Institute (EWRI),a specialty institute within the American Society of Civil Engineers,has provided such a learning opportunity for engineers and scientists from throughout the world.Under the auspices of EWRI,seminar-study tours are scheduled approximately biennially at various locations around the world.Recent locations for seminar-study tour events have been Mexico (2006),Viet Nam (2008),Peru (2010),and China (2011).The Beijing seminar-study tour was held from October 26th to 31st and was hosted and co-sponsored by the School of Environment at Beijing Normal University.In addition to publicity support provided by EWRI,the Beijing seminarstudy tour received financial support from the University of Wisconsin-Green Bay,Green Bay,Wisconsin,USA,with the latter also serving as cosponsor.

  4. Ubiquitous Learning Environment as a Solution to Education Problem

    ZHAO Hailan; Jung-Hwan Park


    Ubiquitous learning means the intelligent learning environment that enables people to learn using any terminal at any place and at any time no matter what the contents may be. This is different from the existing method of learning the information through the internet or studying at specific place, such as school or library, and so on. People do not need to go to specific place at specific time to access the information that they want, but the learning information finds its way to people, which is the biggest difference from the existing method.Ubiquitous learning aims to solve current problems of education in more creative and learner-oriented way by creating an education environment where learners can learn with any terminal anytime and anywhere without regard to contents. The presentation this time would help promote the understanding of the Ubiquitous and explore the ubiquitous education environment that is capable of solving overall problems of education. In addition, it will propose a direction of ubiquitous learning scenario and the change in the educational environment.


    Shvyreva O. I.


    Full Text Available For many consecutive years, one of the main violations on the results of external quality auditing control is the improper validation of the going concern. Our studies have shown that this problem is caused by two reasons. First, this is the normative regulation lack of signs of going concern’s violation. Secondly, this is the unreasonably high role of professional judgment of auditor in identifying and assessing the significance of features of possible liquidation (bankruptcy. The article summarizes the relevant aspects of legislative regulation of going conсern, based on the innovations of recent years. There is substantiated the assessment of the non-compliance with legislation on the net assets and share capital formation, with payment discipline, violations of other regulations influence the probability of forced entity liquidation. To solve the second problem key inadequate identification and assessment of the significance of the going concern features risks have been highlighted. The main directions of internal standardization of going concern’s auditing are suggested and substantiated. The implementation of these proposals will ensure the auditing principles of objectivity, due diligence and sustainability

  6. A solution to the single-question crowd wisdom problem.

    Prelec, Dražen; Seung, H Sebastian; McCoy, John


    Once considered provocative, the notion that the wisdom of the crowd is superior to any individual has become itself a piece of crowd wisdom, leading to speculation that online voting may soon put credentialed experts out of business. Recent applications include political and economic forecasting, evaluating nuclear safety, public policy, the quality of chemical probes, and possible responses to a restless volcano. Algorithms for extracting wisdom from the crowd are typically based on a democratic voting procedure. They are simple to apply and preserve the independence of personal judgment. However, democratic methods have serious limitations. They are biased for shallow, lowest common denominator information, at the expense of novel or specialized knowledge that is not widely shared. Adjustments based on measuring confidence do not solve this problem reliably. Here we propose the following alternative to a democratic vote: select the answer that is more popular than people predict. We show that this principle yields the best answer under reasonable assumptions about voter behaviour, while the standard 'most popular' or 'most confident' principles fail under exactly those same assumptions. Like traditional voting, the principle accepts unique problems, such as panel decisions about scientific or artistic merit, and legal or historical disputes. The potential application domain is thus broader than that covered by machine learning and psychometric methods, which require data across multiple questions.

  7. Nuclear Physics Solutions to the Primordial Lithium Problem

    Williams E.


    Full Text Available The primordial lithium problem is one of the major outstanding issues in the standard model of the Big Bang. Measurements of the baryon to photon ratio in the cosmic microwave background constrain model predictions, giving abundances of 7Li two to four times larger than observed via spectroscopic measurements of metal-poor stars. In an attempt to reconcile this discrepancy, significant effort has been directed at measuring reaction cross sections of light nuclei at astrophysically relevant energies. However, there remain reaction cross sections with large uncertainties, and some that have not yet been measured. Particularly relevant are those involving the destruction of 7Be, a progenitor of 7Li. Key issues that can be improved by nuclear physics input will be highlighted, and the applicability of detectors and event reconstruction techniques recently developed at the ANU will be discussed.

  8. A biological solution to a fundamental distributed computing problem.

    Afek, Yehuda; Alon, Noga; Barad, Omer; Hornstein, Eran; Barkai, Naama; Bar-Joseph, Ziv


    Computational and biological systems are often distributed so that processors (cells) jointly solve a task, without any of them receiving all inputs or observing all outputs. Maximal independent set (MIS) selection is a fundamental distributed computing procedure that seeks to elect a set of local leaders in a network. A variant of this problem is solved during the development of the fly's nervous system, when sensory organ precursor (SOP) cells are chosen. By studying SOP selection, we derived a fast algorithm for MIS selection that combines two attractive features. First, processors do not need to know their degree; second, it has an optimal message complexity while only using one-bit messages. Our findings suggest that simple and efficient algorithms can be developed on the basis of biologically derived insights.

  9. Materials Problems and Solutions in Biomass fired plants

    Larsen, Ole Hede; Montgomery, Melanie


    Owing to Denmark's pledge to reduce carbon dioxide emissions, biomass is being increasingly utilised as a fuel for generating energy. Extensive research and development projects, especially in the area of material performance for biomass fired boilers, have been undertaken to make biomass a viable...... fuel resource. When straw is combusted, potassium chloride and potassium sulphate are present in ash products, which condense on superheater components. This gives rise to specific chlorine corrosion problems not previously encountered in coal fired power plants. The type of corrosion attack can...... plants. With both 10 and 20% straw, no chlorine corrosion was seen. The present paper will describe the results from in situ investigations undertaken in Denmark on high temperature corrosion in biomass fired plants. Results from 100% straw firing, woodchip and cofiring of straw with fossil fuels...

  10. Materials Problems and Solutions in Biomass Fired Plants

    Larsen, Ole Hede; Montgomery, Melanie


    Due to Denmark’s pledge to reduce carbon dioxide emissions, biomass is utilised increasingly as a fuel for generating energy. Extensive research and demonstration projects especially in the area of material performance for biomass fired boilers have been undertaken to make biomass a viable fuel...... resource. When straw is combusted, potassium chloride and potassium sulphate are present in ash products, which condense on superheater components. This gives rise to specific chlorine corrosion problems not previously encountered in coal-fired power plants. The type of corrosion attack can be directly....... With both 10 and 20% straw, no chlorine corrosion was seen. This paper will describe the results from in situ investigations undertaken in Denmark on high temperature corrosion in biomass fired plants. Results from 100% straw-firing, woodchip and co-firing of straw with fossil fuels are summarised...

  11. Complex-Dynamical Approach to Cosmological Problem Solution

    Kirilyuk, A P


    Universe structure emerges in the unreduced, complex-dynamic interaction process with the simplest initial configuration (two attracting homogeneous fields). The unreduced interaction analysis, avoiding any perturbative model, gives intrinsically creative cosmology describing the real, explicitly emerging world structure with dynamic randomness on each scale. Without imposing any postulates or additional entities, we obtain physically real, three-dimensional space, irreversibly flowing time, elementary particles with their detailed structure and intrinsic properties, causally complete and unified version of quantum and relativistic behaviour, the origin and number of naturally unified fundamental forces, classical behaviour emergence in a closed system, and true quantum chaos. Major problems of standard cosmology and astrophysics are consistently solved in this extended picture, including those of quantum cosmology and gravity, entropy growth and time arrow, "hierarchy" of elementary particles (Planckian unit...

  12. A unified solution to the anisotropy and gradient problems

    Gaggero, Daniele; Grasso, Dario; Maccione, Luca


    The Fermi-LAT collaboration recently confirmed a discrepancy between the observed longitudinal profile of gamma-ray diffuse emission from the Galaxy and that computed with numerical codes assuming that Cosmic Rays (CRs) are produced by Galactic supernova remnants; the accurate Fermi-LAT measurements make this anomaly hardly explainable in terms of conventional diffusion schemes. Moreover, experimental data from both Muon detector and Extensive Air Shower experiments about the large scale dipole anisotropy of CRs can hardly be compatible with model predictions within the framework of conventional isotropic and homogeneous propagation. We argue that, accounting for a well physically motivated correlation between the CR escape time and the spatially dependent magnetic turbulence power, it is possible to solve both problems at the same time in a very natural way. Indeed, by exploiting this correlation, we find propagation models that fit a wide set of CR primary and secondary spectra, and consistently reproduce t...

  13. A heuristic solution for the stability problem in conventional submarines

    M. Sinclair


    Full Text Available Seafaring vessels must meet a few very obvious conditions in order to be of any use. The one condition is that they should stay afloat when loaded. The other condition is that they should float upright and with a level keel. The technical terms for these conditions are gravitational stability and trim. In practice some very precise numerical values are calculated for certain parameters in order to describe these conditions. After each refit of a submarine, the numerical values for the parameters referred to above must be recalculated. In the conventional submarines used by the South African Navy these new values must then be translated into the physical redistribution of weights housed in bays in the keel of the submarine. This paper discusses the problem of how this redistribution must be done in order to minimise the amount of work necessary. A heuristic algorithm is proposed by means of which a satisfactory redistribution may economically be computed.

  14. Structure of matter an introductory course with problems and solutions

    Rigamonti, Attilio


    This textbook, now in its third edition, provides a formative introduction to the structure of matter that will serve as a sound basis for students proceeding to more complex courses, thus bridging the gap between elementary physics and topics pertaining to research activities. The focus is deliberately limited to key concepts of atoms, molecules and solids, examining the basic structural aspects without paying detailed attention to the related properties. For many topics the aim has been to start from the beginning and to guide the reader to the threshold of advanced research. This edition includes four new chapters dealing with relevant phases of solid matter (magnetic, electric and superconductive) and the related phase transitions. The book is based on a mixture of theory and solved problems that are integrated into the formal presentation of the arguments. Readers will find it invaluable in enabling them to acquire basic knowledge in the wide and wonderful field of condensed matter and to understand how ...

  15. The existence and the stability of solutions for equilibrium problems with lower and upper bounds

    Congjun Zhang


    Full Text Available In this paper, we study a class of equilibrium problems with lower and upper bounds. We obtain some existence results of solutions for equilibrium problems with lower and upper bounds by employing some classical fixed-point theorems. We investigate the stability of the solution sets for the problems, and establish sufficient conditions for the upper semicontinuity, lower semicontinuity and continuity of the solution set mapping $S:Lambda_1imesLambda_2o2^{X}$ in a Hausdorff topological vector space, in the case where a set $K$ and a mapping $f$ are perturbed respectively by parameters $lambda$ and $mu.$

  16. Asymptotic solution for a class of weakly nonlinear singularly perturbed reaction diffusion problem

    TANG Rong-rong


    Under appropriate conditions, with the perturbation method and the theory of differential inequalities, a class of weakly nonlinear singularly perturbed reaction diffusion problem is considered. The existence of solution of the original problem is proved by constructing the auxiliary functions. The uniformly valid asymptotic expansions of the solution for arbitrary mth order approximation are obtained through constructing the formal solutions of the original problem, expanding the nonlinear terms to the power in small parameter e and comparing the coefficient for the same powers of ε. Finally, an example is provided, resulting in the error of O(ε2).

  17. Minimization of Linear Functionals Defined on| Solutions of Large-Scale Discrete Ill-Posed Problems

    Elden, Lars; Hansen, Per Christian; Rojas, Marielba


    The minimization of linear functionals de ned on the solutions of discrete ill-posed problems arises, e.g., in the computation of con dence intervals for these solutions. In 1990, Elden proposed an algorithm for this minimization problem based on a parametric-programming reformulation involving...... the solution of a sequence of trust-region problems, and using matrix factorizations. In this paper, we describe MLFIP, a large-scale version of this algorithm where a limited-memory trust-region solver is used on the subproblems. We illustrate the use of our algorithm in connection with an inverse heat...

  18. Global existence and blowup of solutions to a free boundary problem for mutualistic model

    KIM; KwangIk


    This article is concerned with a system of semilinear parabolic equations with a free boundary,which arises in a mutualistic ecological model.The local existence and uniqueness of a classical solution are obtained.The asymptotic behavior of the free boundary problem is studied.Our results show that the free problem admits a global slow solution if the inter-specific competitions are strong,while if the inter-specific competitions are weak there exist the blowup solution and global fast solution.

  19. Geometric properties of solutions to the total variation denoising problem

    Chambolle, Antonin; Duval, Vincent; Peyré, Gabriel; Poon, Clarice


    This article studies the denoising performance of total variation (TV) image regularization. More precisely, we study geometrical properties of the solution to the so-called Rudin-Osher-Fatemi total variation denoising method. The first contribution of this paper is a precise mathematical definition of the ‘extended support’ (associated to the noise-free image) of TV denoising. It is intuitively the region which is unstable and will suffer from the staircasing effect. We highlight in several practical cases, such as the indicator of convex sets, that this region can be determined explicitly. Our second and main contribution is a proof that the TV denoising method indeed restores an image which is exactly constant outside a small tube surrounding the extended support. The radius of this tube shrinks toward zero as the noise level vanishes, and we are able to determine, in some cases, an upper bound on the convergence rate. For indicators of so-called ‘calibrable’ sets (such as disks or properly eroded squares), this extended support matches the edges, so that discontinuities produced by TV denoising cluster tightly around the edges. In contrast, for indicators of more general shapes or for complicated images, this extended support can be larger. Beside these main results, our paper also proves several intermediate results about fine properties of TV regularization, in particular for indicators of calibrable and convex sets, which are of independent interest.

  20. IRB Problems and Solutions in Health Communication Research.

    King, Carie S Tucker; Bivens, Kristin Marie; Pumroy, Erin; Rauch, Susan; Koerber, Amy


    In this article, we contribute to the current literature on the difficulties that social scientists encounter with IRBs, but with a focus on the distinct challenges that health communication scholars face in dealing with IRBs at their own institutions and elsewhere. Although health communication researchers, like other communication researchers, can expect to face many of the same challenges that their social science colleagues face during the IRB process, the researcher narratives we present in this article suggest that health communication research presents some distinct challenges because the communication interactions that we investigate occur in highly protected, private spaces, including the medical exam room, online patient forums, and electronic health records. To that end, we present a series of examples in which health communication researchers were able to find solutions or workarounds to the challenges they faced in gaining IRB approval for their research. In every case that we present, the researcher had to revise her initial study design to get around the constraints imposed by IRB requirements, and in every case, the researcher reports having experienced points of incommensurability similar to those reported by many other social scientists. In some situations, investigators even express frustration that the IRB's needs and demands superseded those of healthcare professionals and the patients whom they serve. Additionally, in some situations, investigators' understandings of human subjects' protection actually go further to protect patients' privacy and confidentiality than the IRB required. But, in all four cases that we present, the health communication research was ultimately successful.